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Sample records for red marrow dosimetry

  1. Investigation of effect of variations in bone fraction and red marrow cellularity on bone marrow dosimetry in radio-immunotherapy

    NASA Astrophysics Data System (ADS)

    Wilderman, S. J.; Roberson, P. L.; Bolch, W. E.; Dewaraja, Y. K.

    2013-07-01

    A method is described for computing patient-specific absorbed dose rates to active marrow which accounts for spatial variation in bone volume fraction and marrow cellularity. A module has been added to the 3D Monte Carlo dosimetry program DPM to treat energy deposition in the components of bone spongiosa distinctly. Homogeneous voxels in regions containing bone spongiosa (as defined on CT images) are assumed to be comprised only of bone, active (red) marrow and inactive (yellow) marrow. Cellularities are determined from biopsy, and bone volume fractions are computed from cellularities and CT-derived voxel densities. Electrons are assumed to deposit energy locally in the three constituent components in proportions determined by electron energy absorption fractions which depend on energy, cellularity, and bone volume fraction, and which are either taken from the literature or are derived from Monte Carlo simulations using EGS5. Separate algorithms are used to model primary β particles and secondary electrons generated after photon interactions. Treating energy deposition distinctly in bone spongiosa constituents leads to marrow dosimetry results which differ from homogeneous spongiosa dosimetry by up to 20%. Dose rates in active marrow regions with cellularities of 20, 50, and 80% can vary by up to 20%, and can differ by up to 10% as a function of bone volume fraction. Dose to bone marrow exhibits a strong dependence on marrow cellularity and a potentially significant dependence on bone volume fraction.

  2. Red marrow and blood dosimetry in (131)I treatment of metastatic thyroid carcinoma: pre-treatment versus in-therapy results.

    PubMed

    Giostra, A; Richetta, E; Pasquino, M; Miranti, A; Cutaia, C; Brusasco, G; Pellerito, R E; Stasi, M

    2016-06-01

    Treatment with radioiodine is a standard procedure for patients with well-differentiated thyroid cancer, but the main approach to the therapy is still empiric, consisting of the administration of fixed activities. A predictive individualized dosimetric study may represent an important tool for physicians to determine the best activity to prescribe. The aim of this work is to compare red marrow and blood absorbed dose values obtained in the pre-treatment (PT) dosimetry phase with those obtained in the in-treatment (IT) dosimetry phase in order to estimate the predictive power of PT trial doses and to determine if they can be used as a decision-making tool to safely administer higher (131)I activity to potentially increase the efficacy of treatment. The PT and IT dosimetry for 50 patients has been evaluated using three different dosimetric approaches. In all three approaches blood and red marrow doses, are calculated as the sum of two components, the dose from (131)I activity in the blood and the dose from (131)I activity located in the remainder of the body (i.e. the blood and whole-body contributions to the total dose). PT and IT dose values to blood and red marrow appear to be well correlated irrespective of the dosimetric approach used. Linear regression analyses of PT and IT total doses, for blood and red marrow, and the whole-body contribution to these doses, showed consistent best fit slope and correlation coefficient values of approximately 0.9 and 0.6, respectively: analyses of the blood dose contribution to the total doses also yielded similar values for the best fit slope but with correlation coefficient values of approximately 0.4 reflecting the greater variance in these dose estimates. These findings suggest that pre-treatment red marrow dose assessments may represent an important tool to personalize metastatic thyroid cancer treatment, removing the constraints of a fixed activity approach and permitting potentially more effective higher (131)I

  3. Red marrow and blood dosimetry in 131I treatment of metastatic thyroid carcinoma: pre-treatment versus in-therapy results

    NASA Astrophysics Data System (ADS)

    Giostra, A.; Richetta, E.; Pasquino, M.; Miranti, A.; Cutaia, C.; Brusasco, G.; Pellerito, R. E.; Stasi, M.

    2016-06-01

    Treatment with radioiodine is a standard procedure for patients with well-differentiated thyroid cancer, but the main approach to the therapy is still empiric, consisting of the administration of fixed activities. A predictive individualized dosimetric study may represent an important tool for physicians to determine the best activity to prescribe. The aim of this work is to compare red marrow and blood absorbed dose values obtained in the pre-treatment (PT) dosimetry phase with those obtained in the in-treatment (IT) dosimetry phase in order to estimate the predictive power of PT trial doses and to determine if they can be used as a decision-making tool to safely administer higher 131I activity to potentially increase the efficacy of treatment. The PT and IT dosimetry for 50 patients has been evaluated using three different dosimetric approaches. In all three approaches blood and red marrow doses, are calculated as the sum of two components, the dose from 131I activity in the blood and the dose from 131I activity located in the remainder of the body (i.e. the blood and whole-body contributions to the total dose). PT and IT dose values to blood and red marrow appear to be well correlated irrespective of the dosimetric approach used. Linear regression analyses of PT and IT total doses, for blood and red marrow, and the whole-body contribution to these doses, showed consistent best fit slope and correlation coefficient values of approximately 0.9 and 0.6, respectively: analyses of the blood dose contribution to the total doses also yielded similar values for the best fit slope but with correlation coefficient values of approximately 0.4 reflecting the greater variance in these dose estimates. These findings suggest that pre-treatment red marrow dose assessments may represent an important tool to personalize metastatic thyroid cancer treatment, removing the constraints of a fixed activity approach and permitting potentially more effective higher 131I activities to be

  4. Influence of total-body mass on the scaling of S-factors for patient-specific, blood-based red-marrow dosimetry

    NASA Astrophysics Data System (ADS)

    Traino, A. C.; Ferrari, M.; Cremonesi, M.; Stabin, M. G.

    2007-09-01

    To perform patient-specific, blood-based red-marrow dosimetry, dose conversion factors (the S factors in the MIRD formalism) have to be scaled by patients' organ masses. The dose to red marrow includes both self-dose and cross-irradiation contributions. Linear mass scaling for the self-irradiation term only is usually applied as a first approximation, whereas the cross-irradiation term is considered to be mass independent. Recently, the need of a mass scaling correction on both terms, not necessarily linear and dependent on the radionuclide, has been highlighted in the literature. S-factors taking into account different mass adjustments of organs are available in the OLINDA/EXM code. In this paper, a general algorithm able to fit the mass-dependent factors Srm<--tb and Srm<--rm is suggested and included in a more general equation for red-marrow dose calculation. Moreover, parameters to be considered specifically for therapeutic radionuclides such as 131I, 90Y and 177Lu are reported. The red-marrow doses calculated by the traditional and new algorithms are compared for 131I in ablation therapy (14 pts), 177Lu- (13 pts) and 90Y- (11 pts) peptide therapy for neuroendocrine tumours, and 90Y-Zevalin therapy for NHL (21 pts). The range of differences observed is as follows: -36% to -10% for 131I ablation, -22% to 5% for 177Lu-DOTATATE, -9% to 11% for 90Y-DOTATOC and -8% to 6% for 90Y-Zevalin. All differences are mostly due to the activity in the remainder of the body contributing to cross-irradiation. This paper quantifies the influence of mass scaling adjustment on usually applied therapies and shows how to derive the appropriate parameters for other radionuclides and radiopharmaceuticals.

  5. Bone Marrow Dosimetry Using 124I-PET

    PubMed Central

    Schwartz, Jazmin; Humm, John L.; Divgi, Chaitanya R.; Larson, Steven M.; O'Donoghue, Joseph A.

    2012-01-01

    the assumption of time-independent proportionality between red marrow and plasma activity concentration may be too simplistic. Individualized imaged-based dosimetry is probably required for the optimal therapeutic delivery of radiolabeled antibodies, which does not compromise red marrow and may allow, for some patients, a substantial increase in administered activity and thus tumor dose. PMID:22414633

  6. Evaluation of dual energy quantitative CT for determining the spatial distributions of red marrow and bone for dosimetry in internal emitter radiation therapy

    SciTech Connect

    Goodsitt, Mitchell M. Shenoy, Apeksha; Howard, David; Christodoulou, Emmanuel; Dewaraja, Yuni K.; Shen, Jincheng; Schipper, Matthew J.; Wilderman, Scott; Chun, Se Young

    2014-05-15

    Purpose: To evaluate a three-equation three-unknown dual-energy quantitative CT (DEQCT) technique for determining region specific variations in bone spongiosa composition for improved red marrow dose estimation in radionuclide therapy. Methods: The DEQCT method was applied to 80/140 kVp images of patient-simulating lumbar sectional body phantoms of three sizes (small, medium, and large). External calibration rods of bone, red marrow, and fat-simulating materials were placed beneath the body phantoms. Similar internal calibration inserts were placed at vertebral locations within the body phantoms. Six test inserts of known volume fractions of bone, fat, and red marrow were also scanned. External-to-internal calibration correction factors were derived. The effects of body phantom size, radiation dose, spongiosa region segmentation granularity [single (∼17 × 17 mm) region of interest (ROI), 2 × 2, and 3 × 3 segmentation of that single ROI], and calibration method on the accuracy of the calculated volume fractions of red marrow (cellularity) and trabecular bone were evaluated. Results: For standard low dose DEQCT x-ray technique factors and the internal calibration method, the RMS errors of the estimated volume fractions of red marrow of the test inserts were 1.2–1.3 times greater in the medium body than in the small body phantom and 1.3–1.5 times greater in the large body than in the small body phantom. RMS errors of the calculated volume fractions of red marrow within 2 × 2 segmented subregions of the ROIs were 1.6–1.9 times greater than for no segmentation, and RMS errors for 3 × 3 segmented subregions were 2.3–2.7 times greater than those for no segmentation. Increasing the dose by a factor of 2 reduced the RMS errors of all constituent volume fractions by an average factor of 1.40 ± 0.29 for all segmentation schemes and body phantom sizes; increasing the dose by a factor of 4 reduced those RMS errors by an average factor of 1.71 ± 0.25. Results

  7. Evaluation of dual energy quantitative CT for determining the spatial distributions of red marrow and bone for dosimetry in internal emitter radiation therapy

    PubMed Central

    Goodsitt, Mitchell M.; Shenoy, Apeksha; Shen, Jincheng; Howard, David; Schipper, Matthew J.; Wilderman, Scott; Christodoulou, Emmanuel; Chun, Se Young; Dewaraja, Yuni K.

    2014-01-01

    Purpose: To evaluate a three-equation three-unknown dual-energy quantitative CT (DEQCT) technique for determining region specific variations in bone spongiosa composition for improved red marrow dose estimation in radionuclide therapy. Methods: The DEQCT method was applied to 80/140 kVp images of patient-simulating lumbar sectional body phantoms of three sizes (small, medium, and large). External calibration rods of bone, red marrow, and fat-simulating materials were placed beneath the body phantoms. Similar internal calibration inserts were placed at vertebral locations within the body phantoms. Six test inserts of known volume fractions of bone, fat, and red marrow were also scanned. External-to-internal calibration correction factors were derived. The effects of body phantom size, radiation dose, spongiosa region segmentation granularity [single (∼17 × 17 mm) region of interest (ROI), 2 × 2, and 3 × 3 segmentation of that single ROI], and calibration method on the accuracy of the calculated volume fractions of red marrow (cellularity) and trabecular bone were evaluated. Results: For standard low dose DEQCT x-ray technique factors and the internal calibration method, the RMS errors of the estimated volume fractions of red marrow of the test inserts were 1.2–1.3 times greater in the medium body than in the small body phantom and 1.3–1.5 times greater in the large body than in the small body phantom. RMS errors of the calculated volume fractions of red marrow within 2 × 2 segmented subregions of the ROIs were 1.6–1.9 times greater than for no segmentation, and RMS errors for 3 × 3 segmented subregions were 2.3–2.7 times greater than those for no segmentation. Increasing the dose by a factor of 2 reduced the RMS errors of all constituent volume fractions by an average factor of 1.40 ± 0.29 for all segmentation schemes and body phantom sizes; increasing the dose by a factor of 4 reduced those RMS errors by an average factor of 1.71 ± 0.25. Results

  8. An assessment of bone marrow and bone endosteum dosimetry methods for photon sources

    NASA Astrophysics Data System (ADS)

    Lee, Choonik; Lee, Choonsik; Shah, Amish P.; Bolch, Wesley E.

    2006-11-01

    The rather complex and microscopic histological structure of the skeletal system generally limits one's ability to accurately model this tissue during dosimetric evaluations. Consequently, various assumptions must be made to evaluate the absorbed dose from external and internal photons to the radiosensitive tissues of the red (or haematopoietically active) bone marrow and the osteogenic tissues of the skeletal endosteum. These various methods for photon skeletal dosimetry have not been inter-compared, partly due to the lack of a realistic reference model that can provide a high-resolution three-dimensional geometry for secondary electron particle transport. In the present study, the paired-image radiation transport (PIRT) model developed by Shah et al (2005 J. Nucl. Med. 45 344) was utilized to evaluate the absorbed dose per incident photon fluence to these skeletal regions from idealized parallel beams of monoenergetic photons. The PIRT model results were then used as a local reference against which absorbed doses via other methods were compared. For red bone marrow dosimetry, four approximate techniques were considered: (1) the dose response function method (DRF method) presented in ORNL/TM-8381, (2) the mass-energy absorption coefficient ratio method (two-parameter MEAC method), (3) the MEAC method with the additional use of energy-dependent dose enhancement factors from King and Spiers (1985 Br. J. Radiol. 58 345) (three-parameter MEAC method), and (4) the three-parameter MEAC method applied at the voxel level through the use image-specific CT numbers (CTN method). For the bone endosteum (i.e., bone surfaces), two approximate techniques were compared: (1) the DRF method for bone surfaces and (2) the homogeneous bone approximation (HBA) method. In each case, the local reference standard was assumed to be that of the PIRT model. Four different ex vivo bone specimens with distinctively different internal structures were used in the study: the cranium, the lumbar

  9. Bone marrow dosimetry via microCT imaging and stem cell spatial mapping

    NASA Astrophysics Data System (ADS)

    Kielar, Kayla N.

    In order to make predictions of radiation dose in patients undergoing targeted radionuclide therapy of cancer, an accurate model of skeletal tissues is necessary. Concerning these tissues, the dose-limiting factor in these therapies is the toxicity of the hematopoietically active bone marrow. In addition to acute effects, one must be concerned as well with long-term stochastic effects such as radiation-induced leukemia. Particular cells of interest for both toxicity and cancer risk are the hematopoietic stem cells (HSC), found within the active marrow regions of the skeleton. At present, cellular-level dosimetry models are complex, and thus we cannot model individual stem cells in an anatomic model of the patient. As a result, one reverts to looking at larger tissue regions where these cell populations may reside. To provide a more accurate marrow dose assessment, the skeletal dosimetry model must also be patient-specific. That is, it should be designed to match as closely as possible to the patient undergoing treatment. Absorbed dose estimates then can be tailored based on the skeletal size and trabecular microstructure of an individual for an accurate prediction of marrow toxicity. Thus, not only is it important to accurately model the target tissues of interest in a normal patient, it is important to do so for differing levels of marrow health. A skeletal dosimetry model for the adult female was provided for better predictions of marrow toxicity in patients undergoing radionuclide therapy. This work is the first fully established gender specific model for these applications, and supersedes previous models in scalability of the skeleton and radiation transport methods. Furthermore, the applicability of using bone marrow biopsies was deemed sufficient in prediction of bone marrow health, specifically for the hematopoietic stem cell population. The location and concentration of the HSC in bone marrow was found to follow a spatial gradient from the bone trabeculae

  10. Feasibility study on dosimetry verification of volumetric-modulated arc therapy-based total marrow irradiation.

    PubMed

    Liang, Yun; Kim, Gwe-Ya; Pawlicki, Todd; Mundt, Arno J; Mell, Loren K

    2013-01-01

    The purpose of this study was to develop dosimetry verification procedures for volumetric-modulated arc therapy (VMAT)-based total marrow irradiation (TMI). The VMAT based TMI plans were generated for three patients: one child and two adults. The planning target volume (PTV) was defined as bony skeleton, from head to mid-femur, with a 3 mm margin. The plan strategy similar to published studies was adopted. The PTV was divided into head and neck, chest, and pelvic regions, with separate plans each of which is composed of 2-3 arcs/fields. Multiple isocenters were evenly distributed along the patient's axial direction. The focus of this study is to establish a dosimetry quality assurance procedure involving both two-dimensional (2D) and three-dimensional (3D) volumetric verifications, which is desirable for a large PTV treated with multiple isocenters. The 2D dose verification was performed with film for gamma evaluation and absolute point dose was measured with ion chamber, with attention to the junction between neighboring plans regarding hot/cold spots. The 3D volumetric dose verification used commercial dose reconstruction software to reconstruct dose from electronic portal imaging devices (EPID) images. The gamma evaluation criteria in both 2D and 3D verification were 5% absolute point dose difference and 3 mm of distance to agreement. With film dosimetry, the overall average gamma passing rate was 98.2% and absolute dose difference was 3.9% in junction areas among the test patients; with volumetric portal dosimetry, the corresponding numbers were 90.7% and 2.4%. A dosimetry verification procedure involving both 2D and 3D was developed for VMAT-based TMI. The initial results are encouraging and warrant further investigation in clinical trials. PMID:23470926

  11. Aspects of the dosimetry of radionuclides within the skeleton with particular emphasis on the active marrow

    SciTech Connect

    Eckerman, K.F.

    1985-01-01

    Epidemiological surveys on man and results from animal experiments have shown that two tissues associated with the skeleton are of primary concern with respect to cancer induction by ionizing radiation. These are the cells on or near endosteal surfaces of bone, from which osteosarcomas are thought to arise, and hematopoietic bone marrow, which is associated with leukemia. The complex geometry of the soft tissue-bone intermixture makes calculations of absorbed dose to these target regions a difficult problem. In the case of photon or neutron radiations, charged particle equilibrium may not exist in the vicinity of soft tissue-bone mineral interface. In this paper a general study of the dosimetry of radionuclides within the skeleton is presented. Dosimetric data consistent with the MIRD schema and reflecting the physical and anatomical parameters defining the energy deposition are tabulated for the relevant target regions. 27 refs., 5 figs., 5 tabs.

  12. Estimation of radiation absorbed doses to the red marrow in radioimmunotherapy

    SciTech Connect

    Macey, D.J.; DeNardo, S.J.; DeNardo, G.L.; DeNardo, D.A.; Sui Shen

    1995-02-01

    Myelotoxicity is the dose-limiting factor in radioimmunotherapy. Traditional methods most commonly used to estimate the radiation adsorbed dose to the bone marrow of patients consider contribution from radionuclide in the blood and/or total body. Targeted therapies, such as radioimmunotherapy, add a third potential source for radiation to the bone marrow because the radiolabeled targeting molecules can accumulate specifically on malignant target cells infiltrating the bone marrow. A non-invasive method for estimating the radiation absorbed dose to the red marrow of patients who have received radiolabeled monoclonal antibodies (MoAb) has been developed and explored. The method depends on determining the cumulated activity in three contributing sources: (1) marrow; (2) blood; and (3) total body. The novel aspect of this method for estimating marrow radiation dose is derivation of the radiation dose for the entire red marrow from radiation dose estimates obtained by detection of cumulated activity in three lumbar vertebrae using a gamma camera. Contributions to the marrow radiation dose form marrow, blood, and total body cumulated activity were determined for patients who received an I-131 labeled MoAb, Lym-1, that reacts with malignant B-lymphocytes of chronic lymphocytic leukemia and nonHodgkin`s lymphoma. Six patients were selected for illustrative purposes because their vertebrae were readily visualized on lumbar images. 32 refs., 6 figs., 1 tab.

  13. Bone marrow transplantation for CVID-like humoral immune deficiency associated with red cell aplasia.

    PubMed

    Sayour, Elias J; Mousallem, Talal; Van Mater, David; Wang, Endi; Martin, Paul; Buckley, Rebecca H; Barfield, Raymond C

    2016-10-01

    Patients with common variable immunodeficiency (CVID) have a higher incidence of autoimmune disease, which may mark the disease onset; however, anemia secondary to pure red cell aplasia is an uncommon presenting feature. Here, we describe a case of CVID-like humoral immune deficiency in a child who initially presented with red cell aplasia and ultimately developed progressive bone marrow failure. Although bone marrow transplantation (BMT) has been associated with high mortality in CVID, our patient was successfully treated with a matched sibling BMT and engrafted with >98% donor chimerism and the development of normal antibody titers to diphtheria and tetanus toxoids. PMID:27273469

  14. Hyperemic peripheral red marrow in a patient with sickle cell anemia demonstrated on Tc-99m labeled red blood cell venography

    SciTech Connect

    Heiden, R.A.; Locko, R.C.; Stent, T.R. )

    1991-03-01

    A 25-year-old gravid woman, homozygous for sickle cell anemia, with a history of recent deep venous thrombosis, was examined using Tc-99m labeled red blood cell venography for recurrent thrombosis. Although negative for thrombus, the study presented an unusual incidental finding: the patient's peripheral bone marrow was hyperemic in a distribution consistent with peripheral red bone marrow expansion. Such a pattern has not been documented before using this technique. This report supports other literature that has demonstrated hyperemia of peripheral red bone marrow in other hemolytic anemias. This finding may ultimately define an additional role of scintigraphy in assessing the pathophysiologic status of the sickle cell patient.

  15. SU-E-T-600: In Vivo Dosimetry for Total Body and Total Marrow Irradiations with Optically Stimulated Luminescence Dosimeters

    SciTech Connect

    Niedbala, M; Save, C; Cygler, J

    2014-06-01

    Purpose: To evaluate the feasibility of using optically stimulated luminescence dosimeters (OSLDs) for in-vivo dosimetry of patients undergoing Total Body and Total Marrow Irradiations (TBI and TMI). Methods: TBI treatments of 12 Gy were delivered in 6 BID fractions with the patient on a moving couch under a static 10 MV beam (Synergy, Elekta). TMI treatments of 18 Gy in 9 BID fractions were planned and delivered using a 6 MV TomoTherapy unit (Accuray). To provide a uniform dose to the entire patient length, the treatment was split into 2 adjacent fields junctioned in the thigh region. Our standard clinical practice involves in vivo dosimetry with MOSFETs for each TBI fraction and TLDs for at least one fraction of the TMI treatment for dose verification. In this study we also used OSLDs. Individual calibration coefficients were obtained for the OSLDs based on irradiations in a solid water phantom to the dose of 50 cGy from Elekta Synergy 10 MV (TBI) and 6 MV (TMI) beams. Calibration coefficients were calculated based on the OSLDs readings taken 2 hrs post-irradiation. For in vivo dosimetry OSLDs were placed alongside MOSFETs for TBI patients and in approximately the same locations as the TLDs for TMI patients. OSLDs were read 2 hours post treatment and compared to the MOSFET and TLD results. Results: OSLD measured doses agreed within 5% with MOSFET and TLD results, with the exception of the junction region in the TMI patient due to very high dose gradient and difficulty of precise and reproducible detector placement. Conclusion: OSLDs are useful for in vivo dosimetry of TBI and TMI patients. The quick post-treatment readout is an advantage over TLDs, allowing the results to be obtained between BID fractions, while wireless detectors are advantageous over MOSFETs for treatments involving a moving couch.

  16. Comparison of mathematical models for red marrow and blood absorbed dose estimation in the radioiodine treatment of advanced differentiated thyroid carcinoma

    NASA Astrophysics Data System (ADS)

    Miranti, A.; Giostra, A.; Richetta, E.; Gino, E.; Pellerito, R. E.; Stasi, M.

    2015-02-01

    Metastatic and recurrent differentiated thyroid carcinoma is preferably treated with 131I, whose administered activity is limited by red marrow (RM) toxicity, originally correlated by Benua to a blood absorbed dose higher than 2 Gy. Afterward a variety of dosimetric approaches has been proposed. The aim of this work is to compare the results of the Benua formula with the ones of other three blood and RM absorbed dose formulae. Materials and methods have been borrowed by the dosimetric protocol of the Italian Internal Dosimetry group and adapted to the routine of our centre. Wilcoxon t-tests and percentage differences have been applied for comparison purposes. Results are significantly different (p < 0.05) from each other, with an average percentage difference between Benua versus other results of -22%. The dosimetric formula applied to determine blood or RM absorbed dose may contribute significantly to increase heterogeneity in absorbed dose and dose-response results. Standardization should be a major objective.

  17. 660 nm red light-enhanced bone marrow mesenchymal stem cell transplantation for hypoxic-ischemic brain damage treatment

    PubMed Central

    Li, Xianchao; Hou, Wensheng; Wu, Xiaoying; Jiang, Wei; Chen, Haiyan; Xiao, Nong; Zhou, Ping

    2014-01-01

    Bone marrow mesenchymal stem cell transplantation is an effective treatment for neonatal hypoxic-ischemic brain damage. However, the in vivo transplantation effects are poor and their survival, colonization and differentiation efficiencies are relatively low. Red or near-infrared light from 600–1,000 nm promotes cellular migration and prevents apoptosis. Thus, we hypothesized that the combination of red light with bone marrow mesenchymal stem cell transplantation would be effective for the treatment of hypoxic-ischemic brain damage. In this study, the migration and colonization of cultured bone marrow mesenchymal stem cells on primary neurons after oxygen-glucose deprivation were detected using Transwell assay. The results showed that, after a 40-hour irradiation under red light-emitting diodes at 660 nm and 60 mW/cm2, an increasing number of green fluorescence-labeled bone marrow mesenchymal stem cells migrated towards hypoxic-ischemic damaged primary neurons. Meanwhile, neonatal rats with hypoxic-ischemic brain damage were given an intraperitoneal injection of 1 × 106 bone marrow mesenchymal stem cells, followed by irradiation under red light-emitting diodes at 660 nm and 60 mW/cm2 for 7 successive days. Shuttle box test results showed that, after phototherapy and bone marrow mesenchymal stem cell transplantation, the active avoidance response rate of hypoxic-ischemic brain damage rats was significantly increased, which was higher than that after bone marrow mesenchymal stem cell transplantation alone. Experimental findings indicate that 660 nm red light emitting diode irradiation promotes the migration of bone marrow mesenchymal stem cells, thereby enhancing the contribution of cell transplantation in the treatment of hypoxic-ischemic brain damage. PMID:25206807

  18. Visible red and infrared light alters gene expression in human marrow stromal fibroblast cells

    PubMed Central

    Guo, Jie; Wang, Qing; Wai, Daniel; Zhou, Qunzhou; Shi, Shihong; Le, Anh D; Shi, Songtao; Yen, Stephen L-K

    2015-01-01

    Objectives This study tested whether or not gene expression in human marrow stromal fibroblast (MSF) cells depends on light wavelength and energy density. Material and Methods Primary cultures of isolated human bone marrow stem cells (hBMSC) were exposed to visible red (VR, 633 nm) and infrared (IR, 830) radiation wavelengths from a light emitting diode (LED) over a range of energy densities (0.5, 1.0, 1.5, 2.0 Joules/cm2) Cultured cells were assayed for cell proliferation, osteogenic potential, adipogenesis, mRNA and protein content. mRNA was analyzed by microarray, and compared among different wavelengths and energy densities. Mesenchymal and epithelial cell responses were compared to determine whether responses were cell-type specific. Protein array analysis was used to further analyze key pathways identified by microarrays. Result Different wavelengths and energy densities produced unique sets of genes identified by microarray analysis. Pathway analysis pointed to TGF beta 1 in the visible red and Akt 1 in the infrared wavelengths as key pathways to study. TGF beta protein arrays suggested switching from canonical to non-canonical TGF beta pathways with increases to longer IR wavelengths. Microarrays suggest RANKL and TIMP 10 followed IR energy density dose response curves. Epithelial and mesenchymal cells respond differently to stimulation by light suggesting cell-type specific response is possible. Conclusions These studies demonstrate differential gene expression with different wavelengths, energy densities and cell types. These differences in gene expression have the potential to be exploited for therapeutic purposes and can help explain contradictory results in the literature when wavelengths, energy densities and cell types differ. PMID:25865533

  19. Resolution enhancement in MR spectroscopy of red bone marrow fat via intermolecular double-quantum coherences

    NASA Astrophysics Data System (ADS)

    Bao, Jianfeng; Cui, Xiaohong; Huang, Yuqing; Zhong, Jianhui; Chen, Zhong

    2015-08-01

    High-resolution 1H magnetic resonance spectroscopy (MRS) is generally inaccessible in red bone marrow (RBM) tissues using conventional MRS techniques. This is because signal from these tissues suffers from severe inhomogeneity in the main static B0 field originated from the intrinsic honeycomb structures in trabecular bone. One way to reduce effects of B0 field inhomogeneity is by using the intermolecular double quantum coherence (iDQC) technique, which has been shown in other systems to obtain signals insensitive to B0 field inhomogeneity. In the present study, we employed an iDQC approach to enhance the spectral resolution of RBM. The feasibility and performance of this method for achieving high resolution MRS was verified by experiments on phantoms and pig vertebral bone samples. Unsaturated fatty acid peaks which overlap in the conventional MRS were well resolved and identified in the iDQC spectrum. Quantitative comparison of fractions of three types of fatty acids was performed between iDQC spectra on the in situ RMB and conventional MRS on the extracted fat from the same RBM. Observations of unsaturated fatty acids with iDQC MRS may provide valuable information and may hold potential in diagnosis of diseases such as obesity, diabetes, and leukemia.

  20. Comparison of a restrictive versus liberal red cell transfusion policy for patients with myelodysplasia, aplastic anaemia, and other congenital bone marrow failure disorders

    PubMed Central

    Gu, Yisu; Estcourt, Lise J; Doree, Carolyn; Trivella, Marialena; Hopewell, Sally; Vyas, Paresh

    2015-01-01

    This is the protocol for a review and there is no abstract. The objectives are as follows: To assess the efficacy and safety of a restrictive versus liberal red cell transfusion strategy for patients with long-term bone marrow failure. These include myelodysplasia, acquired aplastic anaemia, and other inherited bone marrow failure disorders. PMID:25983657

  1. Influence of age, sex and calendar year on lifetime accumulated red bone marrow dose from diagnostic radiation exposure.

    PubMed

    Hoffmann, Wolfgang; Meiboom, Merle Friederike; Weitmann, Kerstin; Terschüren, Claudia; von Boetticher, Heiner

    2013-01-01

    Our aim is to evaluate the relevance of different factors influencing lifetime accumulated red bone marrow dose, such as calendar year, age and sex. The lifetime dose was estimated for controls interviewed in person (N = 2811, 37.5% women) of the population-based representative Northern Germany Leukemia and Lymphoma Study. Data were assessed in standardized computer-assisted personal interviews. The calculation of doses is based on a comprehensive quantification model including calendar year, sex, kind of examination, and technical development. In multivariate regression models the annual red bone marrow dose was analyzed depending on age, sex and calendar year to consider simultaneously temporal changes in radiologic practice and individual risk factors. While the number of examinations continuously rises over time, the dose shows two peaks around 1950 and after 1980. Men are exposed to higher doses than woman. Until 1970 traditional examinations like conventional and mass screening examinations caused the main dose. They were then replaced by technically advanced examinations mainly computed tomography and cardiac catheter. The distribution of the red bone marrow dose over lifetime depends highly on the technical standards and radiation protection survey. To a lesser extent it is influenced by age and sex of the subjects. Thus epidemiological studies concerning the assessment of radiation exposure should consider the calendar year in which the examination was conducted. PMID:24244286

  2. Red bone marrow doses, integral absorbed doses, and somatically effective dose equivalent from four maxillary occlusal projections

    SciTech Connect

    Berge, T.I.; Wohni, T.

    1984-02-01

    Phantom measurements of red bone marrow (RBM) doses, integral absorbed doses, and somatically effective dose equivalent (SEDE) from four different maxillary occlusal projections are presented. For each projection, different combinations of focus-skin distances and tube potentials were compared with regard to the patient's radiation load. The axial incisal view produced the highest patient exposures, with a maximum red bone marrow dose of 122.5 microGy/exposure, integral absorbed dose of 8.6 mJ/exposure, and SEDE values of 39.6 microSv/exposure. The corresponding values from the frontal, lateral occlusal, and tuber views ranged between 4% and 44% of the axial incisal view values for the integral absorbed dose and SEDE values, and between 0.3% and 3% for the red bone marrow doses. Increasing the focus-skin distance from 17.5 cm to 27 cm is accompanied by a 24% to 30% reduction in integral absorbed dose. Increasing the tube potential from 50 kV to 65 kV likewise results in a 23% reduction in absorbed energy.

  3. Use of Monte Carlo simulations with a realistic rat phantom for examining the correlation between hematopoietic system response and red marrow absorbed dose in Brown Norway rats undergoing radionuclide therapy with {sup 177}Lu- and {sup 90}Y-BR96 mAbs

    SciTech Connect

    Larsson, Erik; Ljungberg, Michael; Martensson, Linda; Nilsson, Rune; Tennvall, Jan; Strand, Sven-Erik; Joensson, Bo-Anders

    2012-07-15

    Purpose: Biokinetic and dosimetry studies in laboratory animals often precede clinical radionuclide therapies in humans. A reliable evaluation of therapeutic efficacy is essential and should be based on accurate dosimetry data from a realistic dosimetry model. The aim of this study was to develop an anatomically realistic dosimetry model for Brown Norway rats to calculate S factors for use in evaluating correlations between absorbed dose and biological effects in a preclinical therapy study. Methods: A realistic rat phantom (Roby) was used, which has some flexibility that allows for a redefinition of organ sizes. The phantom was modified to represent the anatomic geometry of a Brown Norway rat, which was used for Monte Carlo calculations of S factors. Kinetic data for radiolabeled BR96 monoclonal antibodies were used to calculate the absorbed dose. Biological data were gathered from an activity escalation study with {sup 90}Y- and {sup 177}Lu-labeled BR96 monoclonal antibodies, in which blood cell counts and bodyweight were examined up to 2 months follow-up after injection. Reductions in white blood cell and platelet counts and declines in bodyweight were quantified by four methods and compared to the calculated absorbed dose to the bone marrow or the total body. Results: A red marrow absorbed dose-dependent effect on hematological parameters was observed, which could be evaluated by a decrease in blood cell counts. The absorbed dose to the bone marrow, corresponding to the maximal tolerable activity that could safely be administered, was determined to 8.3 Gy for {sup 177}Lu and 12.5 Gy for {sup 90}Y. Conclusions: There was a clear correlation between the hematological effects, quantified with some of the studied parameters, and the calculated red marrow absorbed doses. The decline in body weight was stronger correlated to the total body absorbed dose, rather than the red marrow absorbed dose. Finally, when considering a constant activity concentration, the phantom

  4. Red bone marrow dose calculations in radiotherapy of prostate cancer based on the updated VCH adult male phantom

    NASA Astrophysics Data System (ADS)

    Ai, Jinqin; Xie, Tianwu; Sun, Wenjuan; Liu, Qian

    2014-04-01

    Red bone marrow (RBM) is an important dose-limiting tissue that has high radiosensitivity but is difficult to identify on clinical medical images. In this study, we investigated dose distribution in RBM for prostate cancer radiotherapy. Four suborgans were identified in the skeleton of the visible Chinese human phantom: cortical bone (CB), trabecular bone (TB), RBM, and yellow bone marrow (YBM). Dose distributions in the phantom were evaluated by the Monte Carlo method. When the left os coxae was taken as the organ-at-risk (OAR), the difference in absorbed dose between RBM and each CB and TB was up to 20%, but was much less (≤3.1%) between RBM and YBM. When the left os coxae and entire bone were both taken as OARs, RBM dose also increased with increasing planning target volume size. The results indicate the validity of using dose to homogeneous bone marrow mixture for estimating dose to RBM when RBM is not available in computational phantoms. In addition, the human skeletal system developed in this study provides a model for considering RBM dose in radiotherapy planning.

  5. Differentiation between Focal Malignant Marrow-Replacing Lesions and Benign Red Marrow Deposition of the Spine with T2*-Corrected Fat-Signal Fraction Map Using a Three-Echo Volume Interpolated Breath-Hold Gradient Echo Dixon Sequence

    PubMed Central

    Kim, Yong Pyo; Kannengiesser, Stephan; Paek, Mun-Young; Chung, Tae-Sub; Yoo, Yeon Hwa; Yoon, Choon-Sik; Song, Ho-Taek; Lee, Young Han; Suh, Jin-Suck

    2014-01-01

    Objective To assess the feasibility of T2*-corrected fat-signal fraction (FF) map by using the three-echo volume interpolated breath-hold gradient echo (VIBE) Dixon sequence to differentiate between malignant marrow-replacing lesions and benign red marrow deposition of vertebrae. Materials and Methods We assessed 32 lesions from 32 patients who underwent magnetic resonance imaging after being referred for assessment of a known or possible vertebral marrow abnormality. The lesions were divided into 21 malignant marrow-replacing lesions and 11 benign red marrow depositions. Three sequences for the parameter measurements were obtained by using a 1.5-T MR imaging scanner as follows: three-echo VIBE Dixon sequence for FF; conventional T1-weighted imaging for the lesion-disc ratio (LDR); pre- and post-gadolinium enhanced fat-suppressed T1-weighted images for the contrast-enhancement ratio (CER). A region of interest was drawn for each lesion for parameter measurements. The areas under the curve (AUC) of the parameters and their sensitivities and specificities at the most ideal cutoff values from receiver operating characteristic curve analysis were obtained. AUC, sensitivity, and specificity were respectively compared between FF and CER. Results The AUCs of FF, LDR, and CER were 0.96, 0.80, and 0.72, respectively. In the comparison of diagnostic performance between the FF and CER, the FF showed a significantly larger AUC as compared to the CER (p = 0.030), although the difference of sensitivity (p = 0.157) and specificity (p = 0.157) were not significant. Conclusion Fat-signal fraction measurement using T2*-corrected three-echo VIBE Dixon sequence is feasible and has a more accurate diagnostic performance, than the CER, in distinguishing benign red marrow deposition from malignant bone marrow-replacing lesions. PMID:25469090

  6. The relative roles of MHC and non-MHC antigens in bone marrow transplantation in rats. Graft acceptance and antigenic expression on donor red blood cells.

    PubMed

    Pinto, M; Gill, T J; Kunz, H W; Dixon-McCarthy, B D

    1983-06-01

    In order to investigate the influence of MHC and non-MHC genes in bone marrow transplantation, various combinations of congenic and inbred strains of rats were used as donors and recipients. A standard regimen of busulfan and cyclophosphamide treatment was used to condition the recipients. The resultant survival patterns of the animals indicated that: (1) a difference across the entire RT1 (MHC) complex is sufficient for the induction of fatal graft-versus-host disease (GVHD) in 100% of the engrafted animals; and (2) the blood group antigens RT2 and RT3, which are controlled by non-MHC genes, do not cause bone marrow graft rejection or GVHD. There were sequential changes of expression in surface alloantigens on the red cells in different donor-recipient combinations without other hematologic changes in the busulfan-cyclophosphamide conditioned bone marrow chimeras. PMID:6346598

  7. A bone marrow toxicity model for 223Ra alpha-emitter radiopharmaceutical therapy

    NASA Astrophysics Data System (ADS)

    Hobbs, Robert F.; Song, Hong; Watchman, Christopher J.; Bolch, Wesley E.; Aksnes, Anne-Kirsti; Ramdahl, Thomas; Flux, Glenn D.; Sgouros, George

    2012-05-01

    Ra-223, an α-particle emitting bone-seeking radionuclide, has recently been used in clinical trials for osseous metastases of prostate cancer. We investigated the relationship between absorbed fraction-based red marrow dosimetry and cell level-dosimetry using a model that accounts for the expected localization of this agent relative to marrow cavity architecture. We show that cell level-based dosimetry is essential to understanding potential marrow toxicity. The GEANT4 software package was used to create simple spheres representing marrow cavities. Ra-223 was positioned on the trabecular bone surface or in the endosteal layer and simulated for decay, along with the descendants. The interior of the sphere was divided into cell-size voxels and the energy was collected in each voxel and interpreted as dose cell histograms. The average absorbed dose values and absorbed fractions were also calculated in order to compare those results with previously published values. The absorbed dose was predominantly deposited near the trabecular surface. The dose cell histogram results were used to plot the percentage of cells that received a potentially toxic absorbed dose (2 or 4 Gy) as a function of the average absorbed dose over the marrow cavity. The results show (1) a heterogeneous distribution of cellular absorbed dose, strongly dependent on the position of the cell within the marrow cavity; and (2) that increasing the average marrow cavity absorbed dose, or equivalently, increasing the administered activity resulted in only a small increase in potential marrow toxicity (i.e. the number of cells receiving more than 4 or 2 Gy), for a range of average marrow cavity absorbed doses from 1 to 20 Gy. The results from the trabecular model differ markedly from a standard absorbed fraction method while presenting comparable average dose values. These suggest that increasing the amount of radioactivity may not substantially increase the risk of toxicity, a result unavailable to the

  8. A bone marrow toxicity model for 223Ra alpha-emitter radiopharmaceutical therapy

    PubMed Central

    Hobbs, Robert F; Song, Hong; Watchman, Christopher J; Bolch, Wesley E; Aksnes, Anne-Kirsti; Ramdahl, Thomas; Flux, Glenn D; Sgouros, George

    2012-01-01

    Purpose Ra-223, an α-particle emitting bone-seeking radionuclide, has recently been used in clinical trials for osseous metasteses of prostate cancer. We investigated the relationship between absorbed fraction-based red marrow dosimetry and cell level-dosimetry using a model that accounts for the expected localization of this agent relative to marrow cavity architecture. We show that cell level-based dosimetry is essential to understanding potential marrow toxicity. Methods The GEANT4 software package was used to create simple spheres representing marrow cavities. Ra-223 was positioned on the trabecular bone surface or in the endosteal layer and simulated for decay, along with the descendants. The interior of the sphere was divided into cell-size voxels and the energy was collected in each voxel and interpreted as dose cell histograms. The average absorbed dose values and absorbed fractions were also calculated in order to compare those results with previously published values. Results The absorbed dose was predominantly deposited near the trabecular surface. The dose cell histograms results were used to plot the percentage of cells that received a potentially toxic absorbed dose (2 or 4 Gy) as a function of the average absorbed dose over the marrow cavity. The results show (1) a heterogeneous distribution of cellular absorbed dose, strongly dependent on the position of the cell within the marrow cavity; and (2) that increasing the average marrow cavity absorbed dose, or equivalently, increasing the administered activity resulted in only a small increase in potential marrow toxicity (i.e., the number of cells receiving more than 4 or 2 Gy), for a range of average marrow cavity absorbed doses from 1 Gy to 20 Gy. Conclusion The results from the trabecular model differ markedly from a standard absorbed fraction method while presenting comparable average dose values. These suggest that increasing the amount of radioactivity may not substantially increase the risk of

  9. Bone Marrow Aspiration and Biopsy

    MedlinePlus

    ... the bone marrow and capability for blood cell production, including red blood cells (RBCs), white blood cells ( ... can affect the bone marrow and blood cell production. A specialist who has expertise in the diagnosis ...

  10. Estimating 131I biokinetics and radiation doses to the red marrow and whole body in thyroid cancer patients: probe detection versus image quantification*

    PubMed Central

    Willegaignon, José; Pelissoni, Rogério Alexandre; Lima, Beatriz Christine de Godoy Diniz; Sapienza, Marcelo Tatit; Coura-Filho, George Barberio; Queiroz, Marcelo Araújo; Buchpiguel, Carlos Alberto

    2016-01-01

    Objective To compare the probe detection method with the image quantification method when estimating 131I biokinetics and radiation doses to the red marrow and whole body in the treatment of thyroid cancer patients. Materials and Methods Fourteen patients with metastatic thyroid cancer, without metastatic bone involvement, were submitted to therapy planning in order to tailor the therapeutic amount of 131I to each individual. Whole-body scans and probe measurements were performed at 4, 24, 48, 72, and 96 h after 131I administration in order to estimate the effective half-life (Teff) and residence time of 131I in the body. Results The mean values for Teff and residence time, respectively, were 19 ± 9 h and 28 ± 12 h for probe detection, compared with 20 ± 13 h and 29 ± 18 h for image quantification. The average dose to the red marrow and whole body, respectively, was 0.061 ± 0.041 mGy/MBq and 0.073 ± 0.040 mGy/MBq for probe detection, compared with 0.066 ± 0.055 mGy/MBq and 0.078 ± 0.056 mGy/MBq for image quantification. Statistical analysis proved that there were no significant differences between the two methods for estimating the Teff (p = 0.801), residence time (p = 0.801), dose to the red marrow (p = 0.708), and dose to the whole body (p = 0.811), even when we considered an optimized approach for calculating doses only at 4 h and 96 h after 131I administration (p > 0.914). Conclusion There is full agreement as to the feasibility of using probe detection and image quantification when estimating 131I biokinetics and red-marrow/whole-body doses. However, because the probe detection method is inefficacious in identifying tumor sites and critical organs during radionuclide therapy and therefore liable to skew adjustment of the amount of 131I to be administered to patients under such therapy, it should be used with caution. PMID:27403014

  11. Phase I/II study of Holmium-166-DOTMP for bone marrow ablation in multiple myeloma prior to bone marrow transplantation (BMT)

    SciTech Connect

    Podoloff, D.A.; Bhadkamkar, V.H.; Kasi, L.P.

    1994-05-01

    We evaluated a bone seeking radionuclide, Ho-166 DOTMP (which has both beta and gamma energies) as an agent for bone marrow ablation prior to bone marrow transplant. Six men and 1 woman in the age range 42-59 yrs. who had previously failed conventional chemotherapy using VAD (Vincristine, Adriamycin, Dexamethasone) were treated. Each patient received a diagnostic dose (Dx) of 30 mCi of Ho-166 DOTMP and underwent serial total body images using photopeak and scatter windows. Transmission images were obtained on day O. Transmission, scatter and photopeak images were used to calculate marrow dose and skeletal uptake. Therapy dose (Tx) was established to deliver a prescribed absorbed dose to the marrow. Bone marrow biopsy samples from lilac crest were obtained to determine activity concentration and to calculate marrow dose. The Dx was followed by a Tx of 25 Gy (3 pts.), 40 Gy (3 pts.) and 50 Gy (1 pt.). Additional total body imaging was accomplished prior to each Tx and SPECT after the final Tx. Bone retention varied from 26-33%. The calculated red marrow dose varied from 11 to 48 Gy. Toxicity was minimal and included: myalgia (1), nausea (2), increased BUN (1), sore throat (1), fever (1x1 day). Bone marrow ablation was achieved in 3/7 pts. The last pt. treated at the highest dose level had greater than 75% reduction in myeloma protein. We conclude that at doses as high as 31.8 mCi/Kg no significant toxicity has been observed. Diagnostic pretherapy imaging and derived dosimetry is helpful in prescribing a red marrow dose prior to radionuclide therapy. The MTD has not yet been reached. However, thus far Ho-166 DOTMP has safely ablated bone marrow prior to BMT.

  12. Bone marrow dosimetry in rats using direct tissue counting after injection of radio-iodinated intact monoclonal antibodies or F(ab')2 fragments

    SciTech Connect

    Buchegger, F.; Chalandon, Y.; Pelegrin, A.; Hardman, N.; Mach, J.P. )

    1991-07-01

    Normal rats were injected intravenously with 131I- and 125I-labeled intact murine and chimeric mouse-human monoclonal antibodies directed against carcinoembryonic antigen or with the corresponding F(ab')2 fragments. At different times after injection, individual animals were killed and radioactivity of blood and major organs, including bones and bone marrow, was determined. Ratios comparing radioactivity concentration in different tissues with that of bone marrow were calculated and found to remain stable during several effective half-lives of the antibodies. Mean bone marrow radioactivity was 35% (range, 29%-40%) of that of blood and 126% (range, 108%-147%) of that of liver after injection of intact Mabs or F(ab')2 fragments. In nude rats bearing human colon carcinoma xenografts producing carcinoembryonic antigen, relative bone marrow radioactivity was slightly lower than that in normal rats.

  13. Internal radiation dosimetry for clinical testing of radiolabeled monoclonal antibodies

    SciTech Connect

    Fisher, D.R.; Durham, J.S.; Hui, T.E.; Hill, R.L.

    1990-11-01

    In gauging the efficacy of radiolabeled monoclonal antibodies in cancer treatment, it is important to know the amount of radiation energy absorbed by tumors and normal tissue per unit administered activity. This paper describes methods for estimating absorbed doses to human tumors and normal tissues, including intraperitoneal tissue surfaces, red marrow, and the intestinal tract from incorporated radionuclides. These methods use the Medical Internal Radiation Dose (MIRD) scheme; however, they also incorporate enhancements designed to solve specific dosimetry problems encountered during clinical studies, such as patient-specific organ masses obtained from computerized tomography (CT) volumetrics, estimates of the dose to tumor masses within normal organs, and multicellular dosimetry for studying dose inhomogeneities in solid tumors. Realistic estimates of absorbed dose are provided within the short time requirements of physicians so that decisions can be made with regard to patient treatment and procurement of radiolabeled antibodies. Some areas in which further research could improve dose assessment are also discussed. 16 refs., 3 figs.

  14. Comparison of a restrictive versus liberal red cell transfusion policy for patients with myelodysplasia, aplastic anaemia, and other congenital bone marrow failure disorders

    PubMed Central

    Gu, Yisu; Estcourt, Lise J; Doree, Carolyn; Hopewell, Sally; Vyas, Paresh

    2015-01-01

    Background Bone marrow failure disorders include a heterogenous group of disorders, of which myelodysplastic syndrome (MDS), forms the largest subgroup. MDS is predominantly a disease of the elderly, with many elderly people managed conservatively with regular allogeneic red blood cell (RBC) transfusions to treat their anaemia. However, RBC transfusions are not without risk. Despite regular transfusions playing a central role in treating such patients, the optimal RBC transfusion strategy (restrictive versus liberal) is currently unclear. Objectives To assess the efficacy and safety of a restrictive versus liberal red blood cell transfusion strategy for patients with myelodysplasia, acquired aplastic anaemia, and other inherited bone marrow failure disorders. Search methods We searched for randomised controlled trials (RCTs) in the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2015, Issue 4), Ovid MEDLINE (from 1946), Ovid EMBASE (from 1974), EBSCO CINAHL (from 1937), the Transfusion Evidence Library (from 1980) and ongoing trial databases to 26th May 2015. Selection criteria RCTs including patients with long-term bone marrow failure disorders that require allogeneic blood transfusion, who are not being actively treated with a haematopoietic stem cell transplant, or intensive chemotherapy. Data collection and analysis We used standard Cochrane review methodology. One author initially screened all references, and excluded any that were clearly irrelevant or duplicates. Two authors then independently screened all abstracts of articles, identified by the review search strategy, for relevancy. Two authors independently assessed the full text of all potentially relevant articles for eligibility, completed the data extraction and assessed the studies for risk of bias using The Cochrane Collaboration’s ’Risk of bias’ tool. Main results We included one trial (13 participants) and identified three ongoing trials that assess RBC

  15. Dual-channel red/blue fluorescence dosimetry with broadband reflectance spectroscopic correction measures protoporphyrin IX production during photodynamic therapy of actinic keratosis

    NASA Astrophysics Data System (ADS)

    Kanick, Stephen Chad; Davis, Scott C.; Zhao, Yan; Hasan, Tayyaba; Maytin, Edward V.; Pogue, Brian W.; Chapman, M. Shane

    2014-07-01

    Dosimetry for aminolevulinic acid (ALA)-induced protoporphyrin IX (PpIX) photodynamic therapy of actinic keratosis was examined with an optimized fluorescence dosimeter to measure PpIX during treatment. While insufficient PpIX generation may be an indicator of incomplete response, there exists no standardized method to quantitate PpIX production at depths in the skin during clinical treatments. In this study, a spectrometer-based point probe dosimeter system was used to sample PpIX fluorescence from superficial (blue wavelength excitation) and deeper (red wavelength excitation) tissue layers. Broadband white light spectroscopy (WLS) was used to monitor aspects of vascular physiology and inform a correction of fluorescence for the background optical properties. Measurements in tissue phantoms showed accurate recovery of blood volume fraction and reduced scattering coefficient from WLS, and a linear response of PpIX fluorescence versus concentration down to 1.95 and 250 nM for blue and red excitations, respectively. A pilot clinical study of 19 patients receiving 1-h ALA incubation before treatment showed high intrinsic variance in PpIX fluorescence with a standard deviation/mean ratio of >0.9. PpIX fluorescence was significantly higher in patients reporting higher pain levels on a visual analog scale. These pilot data suggest that patient-specific PpIX quantitation may predict outcome response.

  16. SU-E-T-121: Dosimetric Characterization of Gafchromic Film EBT3 Using Vidar DosimetryPro Advantage RED and EPSON Expression 10000XL Scanners

    SciTech Connect

    Medina, L; Adrada, A; Filipuzzi, M; Garrigo, E; Venencia, C

    2014-06-01

    Purpose: The purpose of this paper is to characterize EBT3 using two types of scanner, analyzing the factors of influence of each dosimetry system. Methods: The film used in this study was GAFCHROMIC EBT3, the films were exposed at a dose range between 0Gy a 9Gy in a solid water phantom, SSD=100cm, 5cm depth and perpendicularly to the 6MV photon beam generated by a Novalis TX linear accelerator equipped with an HDMLC. A Farmer type ion chamber TN30013 (PTW) was used to determine the dose delivered to the film. The films were digitized with a scanner EPSON expression 10000XL and the VIDAR DosimetryPro Adventage RED. Software RIT113v6.1 was used for construction of the calibration curve and analysis. The film characteristics investigated were: response at different dose levels, sensitivity to orientation and side and resolution through the results of the spatial response function by analyzing a step pattern. Additionally, 20 IMRT treatment fields were measured with both scanner and compared with calculated dose using gamma index analysis (3%-3mm). Results: The OD obtained for dose level 2Gy in the orientation portrait of the film on the scanner EPSON is (0,222±0,19) and for Vidar RED (0,252±0,10) and landscape is for EPSON (0,211±0,25) and for Vidar RED (0,250±0,11) . The orientation dependence with respect to film side is about 0,09% for EPSON and about 0.03% for VIDAR. The spatial response function increase in response to the Gaussian function FWHM EPSON scanner (0.18mm) compared with VIDAR scanner function (less than 0.06mm) was observed. We analyzed 20 total plan dose distributions the number of pixels with gamma>1 (3%-3mm) was 0.7%±1.2 [0.1%; 2.82%] for EBT3-VIDAR y 2%±2.9 [0.2%; 3.5%] for EBT3-EPSON. Conclusion: VIDAR scanner shows better sensitivity. EBT3 film shows a different response between portrait and landscape orientation. Step pattern is better reproduce by VIDAR scanner.

  17. Bone-marrow transplant - series (image)

    MedlinePlus

    Bone-marrow transplants are performed for: deficiencies in red blood cells (aplastic anemia) and white blood cells (leukemia or ... Bone-marrow transplants prolong the life of patients who might otherwise die. As with all major organ transplants, however, ...

  18. Red blood cell production

    MedlinePlus

    ... cells are an important element of blood. Their job is to transport oxygen to the body’s tissues in exchange for carbon dioxide, which is carried to and eliminated by the lungs. Red blood cells are formed in the red bone marrow of bones. Stem cells in the red bone marrow called hemocytoblasts ...

  19. Excess of veno-occlusive disease in a randomized clinical trial on a higher trigger for red blood cell transfusion after bone marrow transplantation: a canadian blood and marrow transplant group trial.

    PubMed

    Robitaille, Nancy; Lacroix, Jacques; Alexandrov, Lubomir; Clayton, Lucy; Cortier, Marion; Schultz, Kirk R; Bittencourt, Henrique; Duval, Michel

    2013-03-01

    Previous studies have shown that maintaining high hemoglobin levels in patients after chemotherapy reduced the length of neutropenia. Thus, we undertook a randomized, controlled, clinical trial in children undergoing allogeneic bone marrow transplantation after receiving a myeloablative conditioning regimen to compare 2 hemoglobin thresholds as triggers for red blood cell transfusion: 120 g/L in the experimental arm and 70 g/L in the control arm. The Data and Safety Monitoring Board closed the study after enrollment of the sixth patient because 3 patients in the experimental arm contracted veno-occlusive disease, but none in the control arm did (P = .05). Ascites was present in all 3 patients, pleura effusion in 2, and portal vein thrombosis in 2. One patient experienced hepatic failure and required treatment with the molecular adsorbent recycling system. Another patient required hemodialysis for renal failure. No major imbalance between groups was seen with regard to risk factors for veno-occlusive disease. Therefore, maintaining the hemoglobin at higher levels should be avoided after hematopoietic stem cell transplantation. PMID:23220014

  20. Establishment of a γ-H2AX foci-based assay to determine biological dose of radon to red bone marrow in rats

    PubMed Central

    Wang, Jing; He, Linfeng; Fan, Dunhuang; Ding, Defang; Wang, Xufei; Gao, Yun; Zhang, Xuxia; Li, Qiang; Chen, Honghong

    2016-01-01

    The biodosimetric information is critical for assessment of cancer risk in populations exposed to high radon. However, no tools are available for biological dose estimation following radon exposure. Here, we established a γ-H2AX foci-based assay to determine biological dose to red bone marrow (RBM) in radon-inhaled rats. After 1–3 h of in vitro radon exposure, a specific pattern of γ-H2AX foci, linear tracks with individual p-ATM and p-DNA-PKcs foci, was observed, and the yield of γ-H2AX foci and its linear tracks displayed a linear dose-response manner in both rat peripheral blood lymphocytes (PBLs) and bone-marrow lymphocytes (BMLs). When the cumulative doses of radon inhaled by rats reached 14, 30 and 60 working level months (WLM), the yields of three types of foci markedly increased in both PBLs and BMLs, and γ-H2AX foci-based dose estimates to RBM were 0.97, 2.06 and 3.94 mGy, respectively. Notably, BMLs displayed a more profound increase of three types of foci than PBLs, and the absorbed dose ratio between BMLs and PBLs was similar between rats exposed to 30 and 60 WLM of radon. Taken together, γ-H2AX foci quantitation in PBLs is able to estimate RBM-absorbed doses with the dose-response curve of γ-H2AX foci after in vitro radon exposure and the ratio of RBM- to PBL-absorbed doses in rats following radon exposure. PMID:27445126

  1. Establishment of a γ-H2AX foci-based assay to determine biological dose of radon to red bone marrow in rats.

    PubMed

    Wang, Jing; He, Linfeng; Fan, Dunhuang; Ding, Defang; Wang, Xufei; Gao, Yun; Zhang, Xuxia; Li, Qiang; Chen, Honghong

    2016-01-01

    The biodosimetric information is critical for assessment of cancer risk in populations exposed to high radon. However, no tools are available for biological dose estimation following radon exposure. Here, we established a γ-H2AX foci-based assay to determine biological dose to red bone marrow (RBM) in radon-inhaled rats. After 1-3 h of in vitro radon exposure, a specific pattern of γ-H2AX foci, linear tracks with individual p-ATM and p-DNA-PKcs foci, was observed, and the yield of γ-H2AX foci and its linear tracks displayed a linear dose-response manner in both rat peripheral blood lymphocytes (PBLs) and bone-marrow lymphocytes (BMLs). When the cumulative doses of radon inhaled by rats reached 14, 30 and 60 working level months (WLM), the yields of three types of foci markedly increased in both PBLs and BMLs, and γ-H2AX foci-based dose estimates to RBM were 0.97, 2.06 and 3.94 mGy, respectively. Notably, BMLs displayed a more profound increase of three types of foci than PBLs, and the absorbed dose ratio between BMLs and PBLs was similar between rats exposed to 30 and 60 WLM of radon. Taken together, γ-H2AX foci quantitation in PBLs is able to estimate RBM-absorbed doses with the dose-response curve of γ-H2AX foci after in vitro radon exposure and the ratio of RBM- to PBL-absorbed doses in rats following radon exposure. PMID:27445126

  2. Establishment of a γ-H2AX foci-based assay to determine biological dose of radon to red bone marrow in rats

    NASA Astrophysics Data System (ADS)

    Wang, Jing; He, Linfeng; Fan, Dunhuang; Ding, Defang; Wang, Xufei; Gao, Yun; Zhang, Xuxia; Li, Qiang; Chen, Honghong

    2016-07-01

    The biodosimetric information is critical for assessment of cancer risk in populations exposed to high radon. However, no tools are available for biological dose estimation following radon exposure. Here, we established a γ-H2AX foci-based assay to determine biological dose to red bone marrow (RBM) in radon-inhaled rats. After 1–3 h of in vitro radon exposure, a specific pattern of γ-H2AX foci, linear tracks with individual p-ATM and p-DNA-PKcs foci, was observed, and the yield of γ-H2AX foci and its linear tracks displayed a linear dose-response manner in both rat peripheral blood lymphocytes (PBLs) and bone-marrow lymphocytes (BMLs). When the cumulative doses of radon inhaled by rats reached 14, 30 and 60 working level months (WLM), the yields of three types of foci markedly increased in both PBLs and BMLs, and γ-H2AX foci-based dose estimates to RBM were 0.97, 2.06 and 3.94 mGy, respectively. Notably, BMLs displayed a more profound increase of three types of foci than PBLs, and the absorbed dose ratio between BMLs and PBLs was similar between rats exposed to 30 and 60 WLM of radon. Taken together, γ-H2AX foci quantitation in PBLs is able to estimate RBM-absorbed doses with the dose-response curve of γ-H2AX foci after in vitro radon exposure and the ratio of RBM- to PBL-absorbed doses in rats following radon exposure.

  3. Effects of elevated temperatures during interruption of irradiation on Harwell Red 4034 PMMA and Kodak Biomax alanine film dosimetry systems

    NASA Astrophysics Data System (ADS)

    Sidereas, P.; Patil, D. S.; Garcia, R.; Tracy, R. P.; Holzman, J. M.

    2007-11-01

    In the industrial setting it is not uncommon for a process interruption to occur during irradiation. In this event, dosimeters may be exposed to prolonged periods of elevated temperature without exposure to ionizing radiation. Once the process is restarted, the same dosimeters are exposed to ionizing radiation in order to achieve target dose. The goal of this experiment was to simulate a process interruption within limits and quantify the effects of a combination of factors (heat, time, and fractionation) on dosimeter response. We present an in-depth experimental study on the response of dosimeters that have been irradiated, stored for a fixed period of time at several temperatures, and then re-irradiated. This study was performed using Harwell Red 4034 polymethylmethacrylate (PMMA) and Kodak BioMax alanine film dosimeters.

  4. Computational dosimetry

    SciTech Connect

    Siebert, B.R.L.; Thomas, R.H.

    1996-01-01

    The paper presents a definition of the term ``Computational Dosimetry`` that is interpreted as the sub-discipline of computational physics which is devoted to radiation metrology. It is shown that computational dosimetry is more than a mere collection of computational methods. Computational simulations directed at basic understanding and modelling are important tools provided by computational dosimetry, while another very important application is the support that it can give to the design, optimization and analysis of experiments. However, the primary task of computational dosimetry is to reduce the variance in the determination of absorbed dose (and its related quantities), for example in the disciplines of radiological protection and radiation therapy. In this paper emphasis is given to the discussion of potential pitfalls in the applications of computational dosimetry and recommendations are given for their avoidance. The need for comparison of calculated and experimental data whenever possible is strongly stressed.

  5. Epid Dosimetry

    NASA Astrophysics Data System (ADS)

    Greer, Peter B.; Vial, Philip

    2011-05-01

    Electronic portal imaging devices (EPIDs) were introduced originally for patient position verification. The idea of using EPIDs for dosimetry was realised in the 1980s. Little was published on the topic until the mid 1990's, when the interest in EPIDs for dosimetry increased rapidly and continues to grow. The increasing research on EPID dosimetry coincided with the introduction of intensity modulated radiation therapy (IMRT). EPIDs are well suited to IMRT dosimetry because they are high resolution, two-dimensional (2D) digital detectors. They are also pre-existing on almost all modern linear accelerators. They generally show a linear response to increasing dose. Different types of EPIDs have been clinically implemented, and these have been described in several review papers. The current generation of commercially available EPIDs are indirect detection active matrix flat panel imagers, also known as amorphous silicon (a-Si) EPIDs. Disadvantages of a-Si EPIDs for dosimetry include non-water equivalent construction materials, and the energy sensitivity and optical scatter of the phosphor scintillators used to create optical signal from the megavoltage beam. This report discusses current knowledge regarding a-Si EPIDs for dosimetry.

  6. Epid Dosimetry

    SciTech Connect

    Greer, Peter B.; Vial, Philip

    2011-05-05

    Electronic portal imaging devices (EPIDs) were introduced originally for patient position verification. The idea of using EPIDs for dosimetry was realised in the 1980s. Little was published on the topic until the mid 1990's, when the interest in EPIDs for dosimetry increased rapidly and continues to grow. The increasing research on EPID dosimetry coincided with the introduction of intensity modulated radiation therapy (IMRT). EPIDs are well suited to IMRT dosimetry because they are high resolution, two-dimensional (2D) digital detectors. They are also pre-existing on almost all modern linear accelerators. They generally show a linear response to increasing dose. Different types of EPIDs have been clinically implemented, and these have been described in several review papers. The current generation of commercially available EPIDs are indirect detection active matrix flat panel imagers, also known as amorphous silicon (a-Si) EPIDs. Disadvantages of a-Si EPIDs for dosimetry include non-water equivalent construction materials, and the energy sensitivity and optical scatter of the phosphor scintillators used to create optical signal from the megavoltage beam. This report discusses current knowledge regarding a-Si EPIDs for dosimetry.

  7. Bone marrow transplant

    MedlinePlus

    Transplant - bone marrow; Stem cell transplant; Hematopoietic stem cell transplant; Reduced intensity nonmyeloablative transplant; Mini transplant; Allogenic bone marrow transplant; Autologous bone marrow transplant; ...

  8. Bone marrow transplant

    MedlinePlus

    Transplant - bone marrow; Stem cell transplant; Hematopoietic stem cell transplant; Reduced intensity, nonmyeloablative transplant; Mini transplant; Allogenic bone marrow transplant; Autologous bone marrow transplant; Umbilical ...

  9. (Biological dosimetry)

    SciTech Connect

    Preston, R.J.

    1990-12-17

    The traveler attended the 1st International Conference on Biological Dosimetry in Madrid, Spain. This conference was organized to provide information to a general audience of biologists, physicists, radiotherapists, industrial hygiene personnel and individuals from related fields on the current ability of cytogenetic analysis to provide estimates of radiation dose in cases of occupational or environmental exposure. There is a growing interest in Spain in biological dosimetry because of the increased use of radiation sources for medical and occupational uses, and with this the anticipated and actual increase in numbers of overexposure. The traveler delivered the introductory lecture on Biological Dosimetry: Mechanistic Concepts'' that was intended to provide a framework by which the more applied lectures could be interpreted in a mechanistic way. A second component of the trip was to provide advice with regard to several recent cases of overexposure that had been or were being assessed by the Radiopathology and Radiotherapy Department of the Hospital General Gregorio Maranon'' in Madrid. The traveler had provided information on several of these, and had analyzed cells from some exposed or purportedly exposed individuals. The members of the biological dosimetry group were referred to individuals at REACTS at Oak Ridge Associated Universities for advice on follow-up treatment.

  10. Neutron personnel dosimetry

    SciTech Connect

    Griffith, R.V.

    1981-06-16

    The current state-of-the-art in neutron personnel dosimetry is reviewed. Topics covered include dosimetry needs and alternatives, current dosimetry approaches, personnel monitoring devices, calibration strategies, and future developments. (ACR)

  11. Radiation dosimetry.

    PubMed Central

    Cameron, J

    1991-01-01

    This article summarizes the basic facts about the measurement of ionizing radiation, usually referred to as radiation dosimetry. The article defines the common radiation quantities and units; gives typical levels of natural radiation and medical exposures; and describes the most important biological effects of radiation and the methods used to measure radiation. Finally, a proposal is made for a new radiation risk unit to make radiation risks more understandable to nonspecialists. PMID:2040250

  12. Extension of the biological effective dose to the MIRD schema and possible implications in radionuclide therapy dosimetry

    SciTech Connect

    Baechler, Sebastien; Hobbs, Robert F.; Prideaux, Andrew R.; Wahl, Richard L.; Sgouros, George

    2008-03-15

    In dosimetry-based treatment planning protocols, patients with rapid clearance of the radiopharmaceutical require a larger amount of initial activity than those with slow clearance to match the absorbed dose to the critical organ. As a result, the dose-rate to the critical organ is higher in patients with rapid clearance and may cause unexpected toxicity compared to patients with slow clearance. In order to account for the biological impact of different dose-rates, radiobiological modeling is beginning to be applied to the analysis of radionuclide therapy patient data. To date, the formalism used for these analyses is based on kinetics derived from activity in a single organ, the target. This does not include the influence of other source organs to the dose and dose-rate to the target organ. As a result, only self-dose irradiation in the target organ contributes to the dose-rate. In this work, the biological effective dose (BED) formalism has been extended to include the effect of multiple source organ contributions to the net dose-rate in a target organ. The generalized BED derivation has been based on the Medical Internal Radionuclide Dose Committee (MIRD) schema assuming multiple source organs following exponential effective clearance of the radionuclide. A BED-based approach to determine the largest safe dose to critical organs has also been developed. The extended BED formalism is applied to red marrow dosimetry, as well as kidney dosimetry considering the cortex and the medulla separately, since both those organs are commonly dose limiting in radionuclide therapy. The analysis shows that because the red marrow is an early responding tissue (high {alpha}/{beta}), it is less susceptible to unexpected toxicity arising from rapid clearance of high levels of administered activity in the marrow or in the remainder of the body. In kidney dosimetry, the study demonstrates a complex interplay between clearance of activity in the cortex and the medulla, as well as the

  13. Personalized estimation of dose to red bone marrow and the associated leukaemia risk attributable to pelvic kilo-voltage cone beam computed tomography scans in image-guided radiotherapy

    NASA Astrophysics Data System (ADS)

    Zhang, Yibao; Yan, Yulong; Nath, Ravinder; Bao, Shanglian; Deng, Jun

    2012-07-01

    The aim of this study is to investigate the imaging dose to red bone marrow (RBM) and the associated leukaemia risks attributable to pelvic kilo-voltage cone beam computed tomography (kVCBCT) scans in image-guided radiation therapy (IGRT). The RBM doses of 42 patients (age 2.7-86.4 years) were calculated using Monte Carlo simulations. The trabecular spongiosa was segmented to substitute RBM rather than the whole bone. Quantitative correlations between anthropometric variables such as age, physical bone density (PBD) and RBM dose were established. Personalized leukaemia risk was evaluated using an improved Boice model which included the age-associated RBM involvement. An incremental leukaemia risk of 29%-82% (mean = 45%) was found to be associated with 40 pelvic kVCBCT scans in the subject group used in a typical external beam radiation therapy course. Higher risks were observed in children. Due to the enhanced photoelectric effect in high atomic number materials, PBD was observed to strongly affect the RBM dose. Considerable overestimations (9%-42%, mean = 28%) were observed if the whole bone doses were used as surrogates of RBM doses. The personalized estimation of RBM dose and associated leukaemia risk caused by pelvic kVCBCT scans is clinically feasible with the proposed empirical models. Higher radiogenic cancer risks are associated with repeated kVCBCT scans in IGRT of cancer patients, especially children.

  14. Bone marrow biopsy

    MedlinePlus

    Biopsy - bone marrow ... A bone marrow biopsy may be done in the health care provider's office or in a hospital. The sample may be taken from the pelvic or breast bone. Sometimes, other areas are used. Marrow is removed ...

  15. The radiation dosimetry of intrathecally administered radionuclides

    SciTech Connect

    Stabin, M.G.; Evans, J.F.

    1999-01-01

    The radiation dose to the spine, spinal cord, marrow, and other organs of the body from intrathecal administration of several radiopharmaceuticals was studied. Anatomic models were developed for the spine, spinal cerebrospinal fluid (CSF), spinal cord, spinal skeleton, cranial skeleton, and cranial CSF. A kinetic model for the transport of CSF was used to determine residence times in the CSF; material leaving the CSF was thereafter assumed to enter the bloodstream and follow the kinetics of the radiopharmaceutical as if intravenously administered. The radiation transport codes MCNP and ALGAMP were used to model the electron and photon transport and energy deposition. The dosimetry of Tc-99m DTPA and HSA, In-111 DTPA, I-131 HSA, and Yb-169 DTPA was studied. Radiation dose profiles for the spinal cord and marrow in the spine were developed and average doses to all other organs were estimated, including dose distributions within the bone and marrow.

  16. Bone marrow transplant - discharge

    MedlinePlus

    Transplant - bone marrow - discharge; Stem cell transplant - discharge; Hematopoietic stem cell transplant - discharge; Reduced intensity; Non-myeloablative transplant - discharge; Mini transplant - discharge; Allogenic bone marrow transplant - ...

  17. Personnel neutron dosimetry

    SciTech Connect

    Hankins, D.

    1982-04-01

    This edited transcript of a presentation on personnel neutron discusses the accuracy of present dosimetry practices, requirements, calibration, dosemeter types, quality factors, operational problems, and dosimetry for a criticality accident. 32 figs. (ACR)

  18. New dosimetry of atomic bomb radiations.

    PubMed

    Fry, R J; Sinclair, W K

    1987-10-10

    The reassessment of the radiation dosimetry from the Hiroshima and Nagasaki atomic bombs is almost complete. Since atomic bomb survivors provide a major source of data for estimates of risk of cancer induction by radiation the impact of the new dosimetry on risk estimates and radiation protection standards is important. The changes include an increase of about 20% in the estimated yield of the Hiroshima bomb and a reduction in the estimated doses from neutrons in both cities. The estimated neutron dose for Hiroshima is about 10% of the previous estimate. The neutron doses are now so small that direct estimates of neutron relative biological effectiveness may be precluded or be much more difficult. There is little change in most of the gamma ray organ doses because various changes in the new estimates tend to cancel each other out. The new estimate of the attenuation of the free-in-air kerma by the walls of the homes is about twice that used in the previous dosimetry. But the transmission of gamma radiation to the deep organs such as bone marrow is significantly greater than earlier estimates. Probably future risk estimates for radiogenic cancer will be somewhat higher because of both the new dosimetry and the new cancer mortality data. New risk estimates should be available in 1988. PMID:2889042

  19. Imaging of Bone Marrow.

    PubMed

    Lin, Sopo; Ouyang, Tao; Kanekar, Sangam

    2016-08-01

    Bone marrow is the essential for function of hematopoiesis, which is vital for the normal functioning of the body. Bone marrow disorders or dysfunctions may be evaluated by blood workup, peripheral smears, marrow biopsy, plain radiographs, computed tomography (CT), MRI and nuclear medicine scan. It is important to distinguish normal spinal marrow from pathology to avoid missing a pathology or misinterpreting normal changes, either of which may result in further testing and increased health care costs. This article focuses on the diffuse bone marrow pathologies, because the majority of the bone marrow pathologies related to hematologic disorders are diffuse. PMID:27444005

  20. Bone marrow (stem cell) donation

    MedlinePlus

    Stem cell transplant; Allogeneic-donation ... There are two types of bone marrow donation: Autologous bone marrow transplant is when people donate their own bone marrow. "Auto" means self. Allogenic bone marrow transplant is when another person ...

  1. Bone Marrow Diseases

    MedlinePlus

    Bone marrow is the spongy tissue inside some of your bones, such as your hip and thigh bones. ... the platelets that help with blood clotting. With bone marrow disease, there are problems with the stem cells ...

  2. Bone Marrow Transplantation

    MedlinePlus

    Bone marrow is the spongy tissue inside some of your bones, such as your hip and thigh bones. ... platelets, which help the blood to clot. A bone marrow transplant is a procedure that replaces a person's ...

  3. Bone marrow aspiration

    MedlinePlus

    ... this page: //medlineplus.gov/ency/article/003658.htm Bone marrow aspiration To use the sharing features on this page, please enable JavaScript. Bone marrow is the soft tissue inside bones that helps ...

  4. Bone marrow aspiration

    MedlinePlus

    ... creates suction. A small sample of bone marrow fluid flows into the tube. The needle is removed. Pressure and then a bandage are applied to the skin. The bone marrow fluid is sent to a laboratory and examined under ...

  5. Bone Marrow Diseases

    MedlinePlus

    ... that help with blood clotting. With bone marrow disease, there are problems with the stem cells or ... marrow makes too many white blood cells Other diseases, such as lymphoma, can spread into the bone ...

  6. Chemical dosimetry system for criticality accidents.

    PubMed

    Miljanić, Saveta; Ilijas, Boris

    2004-01-01

    Ruder Bosković Institute (RBI) criticality dosimetry system consists of a chemical dosimetry system for measuring the total (neutron + gamma) dose, and a thermoluminescent (TL) dosimetry system for a separate determination of the gamma ray component. The use of the chemical dosemeter solution chlorobenzene-ethanol-trimethylpentane (CET) is based on the radiolytic formation of hydrochloric acid, which protonates a pH indicator, thymolsulphonphthalein. The high molar absorptivity of its red form at 552 nm is responsible for a high sensitivity of the system: doses in the range 0.2-15 Gy can be measured. The dosemeter has been designed as a glass ampoule filled with the CET solution and inserted into a pen-shaped plastic holder. For dose determinations, a newly constructed optoelectronic reader has been used. The RBI team took part in the International Intercomparison of Criticality Accident Dosimetry Systems at the SILENE Reactor, Valduc, June 2002, with the CET dosimetry system. For gamma ray dose determination TLD-700 TL detectors were used. The results obtained with CET dosemeter show very good agreement with the reference values. PMID:15353694

  7. Starvation marrow - gelatinous transformation of bone marrow.

    PubMed

    Osgood, Eric; Muddassir, Salman; Jaju, Minal; Moser, Robert; Farid, Farwa; Mewada, Nishith

    2014-01-01

    Gelatinous bone marrow transformation (GMT), also known as starvation marrow, represents a rare pathological entity of unclear etiology, in which bone marrow histopathology demonstrates hypoplasia, fat atrophy, and gelatinous infiltration. The finding of gelatinous marrow transformation lacks disease specificity; rather, it is an indicator of severe illness and a marker of poor nutritional status, found in patients with eating disorders, acute febrile illnesses, acquired immunodeficiency syndrome, alcoholism, malignancies, and congestive heart failure. We present a middle-aged woman with a history of alcoholism, depression, and anorexia nervosa who presented with failure to thrive and macrocytic anemia, with bone marrow examination demonstrative of gelatinous transformation, all of which resolved with appropriate treatment. To our knowledge, there are very few cases of GMT which have been successfully treated; thus, our case highlights the importance of proper supportive management. PMID:25317270

  8. Bone marrow biopsy

    MedlinePlus

    Biopsy - bone marrow ... A bone marrow biopsy may be done in the health care provider's office or in a hospital. The sample may ... This captures a tiny sample, or core, of bone marrow within the needle. The sample and needle are ...

  9. A STUDY OF PREDICTED BONE MARROW DISTRIBUTION ON CALCULATED MARROW DOSE FROM EXTERNAL RADIATION EXPOSURES USING TWO SETS OF IMAGE DATA FOR THE SAME INDIVIDUAL

    PubMed Central

    Caracappa, Peter F.; Chao, T. C. Ephraim; Xu, X. George

    2010-01-01

    Red bone marrow is among the tissues of the human body that are most sensitive to ionizing radiation, but red bone marrow cannot be distinguished from yellow bone marrow by normal radiographic means. When using a computational model of the body constructed from computed tomography (CT) images for radiation dose, assumptions must be applied to calculate the dose to the red bone marrow. This paper presents an analysis of two methods of calculating red bone marrow distribution: 1) a homogeneous mixture of red and yellow bone marrow throughout the skeleton, and 2) International Commission on Radiological Protection cellularity factors applied to each bone segment. A computational dose model was constructed from the CT image set of the Visible Human Project and compared to the VIP-Man model, which was derived from color photographs of the same individual. These two data sets for the same individual provide the unique opportunity to compare the methods applied to the CT-based model against the observed distribution of red bone marrow for that individual. The mass of red bone marrow in each bone segment was calculated using both methods. The effect of the different red bone marrow distributions was analyzed by calculating the red bone marrow dose using the EGS4 Monte Carlo code for parallel beams of monoenergetic photons over an energy range of 30 keV to 6 MeV, cylindrical (simplified CT) sources centered about the head and abdomen over an energy range of 30 keV to 1 MeV, and a whole-body electron irradiation treatment protocol for 3.9 MeV electrons. Applying the method with cellularity factors improves the average difference in the estimation of mass in each bone segment as compared to the mass in VIP-Man by 45% over the homogenous mixture method. Red bone marrow doses calculated by the two methods are similar for parallel photon beams at high energy (above about 200 keV), but differ by as much as 40% at lower energies. The calculated red bone marrow doses differ

  10. Thin film tritium dosimetry

    DOEpatents

    Moran, Paul R.

    1976-01-01

    The present invention provides a method for tritium dosimetry. A dosimeter comprising a thin film of a material having relatively sensitive RITAC-RITAP dosimetry properties is exposed to radiation from tritium, and after the dosimeter has been removed from the source of the radiation, the low energy electron dose deposited in the thin film is determined by radiation-induced, thermally-activated polarization dosimetry techniques.

  11. Skeletal dosimetry in a voxel-based rat phantom for internal exposures to photons and electrons

    SciTech Connect

    Xie Tianwu; Han Dao; Liu Yang; Sun Wenjuan; Liu Qian

    2010-05-15

    Purpose: The skeleton makes a significant contribution to the whole body absorbed dose evaluation of rats, since the bone marrow and bone surface in the skeleton express high radiosensitivity and are considered to be important dose-limiting tissues. The bone marrow can be categorized as red bone marrow (RBM) and yellow bone marrow (YBM). It is important to investigate the bone marrow in skeletal dosimetry. Methods: Cryosectional color images of the skeleton of a 156 g rat were segmented into mineral bone (including cortical bone and trabecular bone), RBM, and YBM. These three tissue types were identified at 40 different bone sites and integrated into a previously developed voxel-based rat computational phantom. Photon and electron skeletal absorbed fractions were then calculated using the MCNPX Monte Carlo code. Results: Absorbed fraction (AF) and specific absorbed fraction (SAF) for mineral bone, RBM, and YBM at the 40 different bone sites were established for monoenergetic photon and electron sources placed in 18 organs and seven bone sites. Discrete photon energy was varied from 0.01 to 5.0 MeV in 21 discrete steps, while 21 discrete electron energies were studied, from 0.1 to 10.0 MeV. The trends and values found were consistent with the results of other researchers [M. G. Stabin, T. E. Peterson, G. E. Holburn, and M. A. Emmons, ''Voxel-based mouse and rat models for internal dose calculations,'' J. Nucl. Med. 47, 655-659 (2006)]. S-factors for the radionuclides {sup 169}Er, {sup 143}Pr, {sup 89}Sr, {sup 32}P, and {sup 90}Y, located in 18 organs and seven bone sites for the skeleton, were calculated and are provided in detail. Conclusions: For internal dose calculations, the AF data reveal that the mineral bone in the rat skeletal system is responsible for significant attenuation of gamma rays, especially at low energies. The photon SAF curves of RBM show that, for photon energies greater than 0.6 MeV, there is an increase in secondary photons emitted from the

  12. International Reactor Dosimetry Data.

    Energy Science and Technology Software Center (ESTSC)

    1982-06-28

    Version 00 IRDF-82 contains 620 neutron group cross sections (SAND-II format) based on the ENDF/B-V Special Purpose Dosimetry File as well as other reaction cross sections important for dosimetry applications. In addition, multigroup spectra for ten reference benchmarks are also provided.

  13. [Pharmacokinetic substantiation of the use of 111In-citrate in bone marrow studies].

    PubMed

    Korsunskiĭ, V N; Tarasenko, Iu I; Koval'chuk, N D; Kosheleva, I Iu; Popov, V I

    1986-07-01

    Soviet radiopharmaceutical 111In-citrin has been studied to define its possible application for marrow visualization. 111In-citrin has been shown to accumulate in the red marrow, parenchymal organs and to be excreted from animal organism by urinary system predominately. 111In-citrin has advantages in defining the nuclide concentrations in marrow blood and serum as compared with colloid preparations and 111In-chloride. 111In-citrin is supposed to be an adequate radiopharmaceutical preparation for visualization of the red marrow. PMID:3736386

  14. Bone Marrow Transplantation

    MedlinePlus

    Bone marrow is the spongy tissue inside some of your bones, such as your hip and thigh bones. It contains immature cells, called stem cells. The ... platelets, which help the blood to clot. A bone marrow transplant is a procedure that replaces a ...

  15. Practical CT dosimetry

    SciTech Connect

    Yoshizumi, T.T.; Suneja, S.K.; Teal, J.S. )

    1989-07-01

    The dose from computed tomography (CT) examinations is not negligible from a radiation safety standpoint. Occasionally, one encounters a case in which an unsuspected pregnant woman undergoes a CT pelvic scan, and the radiologist is required to estimate the dose to the fetus. This article addresses practical methods of CT dosimetry with a specific discussion on fetal dose estimate. Three methods are described: (1) the use of a dose chart, (2) the pencil ionization chamber method, and (3) the thermoluminescence dosimetry (TLD) method.

  16. Bone marrow culture

    MedlinePlus

    ... 2015 Updated by: Yi-Bin Chen, MD, Leukemia/Bone Marrow Transplant Program, Massachusetts General Hospital, Boston, MA. Also reviewed ... M. is also a founding member of Hi-Ethics and subscribes to the principles of the Health ...

  17. Hydroxyanthraquinone dye solutions for radiation dosimetry.

    PubMed

    Bedear El-Assy, N; Alian, A; Abdel Rahim, F; Roushdy, H

    1982-06-01

    An investigation has been carried out on the effect of gamma-radiation on the absorption spectra of aqueous solutions of the hydroxyanthraquinone dyes, alizarin and alizarin red S. Ionizing radiation at absorbed doses over the range 10(5)-3 x 10(6) rad brought about gradual bleaching of aerated (oxygenated) dye solutions. The radiolytic bleaching was enhanced through addition of hydrogen peroxide, as expected. A mechanism for the radiolytic reaction is proposed, based on chemical attack of the chromophore by radicals and radical ions as aqueous radiolysis products. Suggestions are made for possible radiation dosimetry by means of spectrophotometric analysis of the absorption spectra. PMID:7107037

  18. Bone marrow fat.

    PubMed

    Hardouin, Pierre; Pansini, Vittorio; Cortet, Bernard

    2014-07-01

    Bone marrow fat (BMF) results from an accumulation of fat cells within the bone marrow. Fat is not a simple filling tissue but is now considered as an actor within bone microenvironment. BMF is not comparable to other fat depots, as in subcutaneous or visceral tissues. Recent studies on bone marrow adipocytes have shown that they do not appear only as storage cells, but also as cells secreting adipokines, like leptin and adiponectin. Moreover bone marrow adipocytes share the same precursor with osteoblasts, the mesenchymal stem cell. It is now well established that high BMF is associated with weak bone mass in osteoporosis, especially during aging and anorexia nervosa. But numerous questions remain discussed: what is the precise phenotype of bone marrow adipocytes? What is the real function of BMF, and how does bone marrow adipocyte act on its environment? Is the increase of BMF during osteoporosis responsible for bone loss? Is BMF involved in other diseases? How to measure BMF in humans? A better understanding of BMF could allow to obtain new diagnostic tools for osteoporosis management, and could open major therapeutic perspectives. PMID:24703396

  19. Internal dosimetry of tritium

    SciTech Connect

    LaBone, T.R.

    1992-01-01

    Tritium is an interesting radionuclide from the perspective of internal dosimetry because of the wide variety of chemical compounds in which it can appear, its unusual routes of entry into the body, and its ability to exchange with stable hydrogen in surrounding material. In this report the internal dosimetry of tritium compounds is reviewed, with emphasis on methods of evaluating bioassay data following chronic and acute intakes. The assumptions and models used in the derivation of Annual Limits on Intake (ALI) and Derived Air Concentrations (DAC) for tritium are also discussed.

  20. Internal dosimetry of tritium

    SciTech Connect

    LaBone, T.R.

    1992-06-01

    Tritium is an interesting radionuclide from the perspective of internal dosimetry because of the wide variety of chemical compounds in which it can appear, its unusual routes of entry into the body, and its ability to exchange with stable hydrogen in surrounding material. In this report the internal dosimetry of tritium compounds is reviewed, with emphasis on methods of evaluating bioassay data following chronic and acute intakes. The assumptions and models used in the derivation of Annual Limits on Intake (ALI) and Derived Air Concentrations (DAC) for tritium are also discussed.

  1. Dosimetry with diamond detectors

    NASA Astrophysics Data System (ADS)

    Gervino, G.; Marino, C.; Silvestri, F.; Lavagno, A.; Truc, F.

    2010-05-01

    In this paper we present the dosimetry analysis in terms of stability and repeatability of the signal and dose rate dependence of a synthetic single crystal diamond grown by Chemical Vapor Deposition (CVD) technique. The measurements carried out by 5 MeV X-ray photons beam show very promising results, even if the dose rate detector response points out that the charge trapping centers distribution is not uniform inside the crystal volume. This handicap that affects the detectors performances, must be ascribed to the growing process. Synthetic single crystal diamonds could be a valuable alternative to air ionization chambers for quality beam control and for intensity modulated radiation therapy beams dosimetry.

  2. WE-E-BRE-01: An Image-Based Skeletal Dosimetry Model for the ICRP Reference Adult Female - Internal Electron Sources

    SciTech Connect

    O'Reilly, S; Maynard, M; Marshall, E; Bolch, W; Sinclair, L; Rajon, D; Wayson, M

    2014-06-15

    Purpose: Limitations seen in previous skeletal dosimetry models, which are still employed in commonly used software today, include the lack of consideration of electron escape and cross-fire from cortical bone, the modeling of infinite spongiosa, the disregard of the effect of varying cellularity on active marrow self-irradiation, and the lack of use of the more recent ICRP definition of a 50 micron surrogate tissue region for the osteoprogenitor cells - shallow marrow. These limitations were addressed in the present dosimetry model. Methods: Electron transport was completed to determine specific absorbed fractions to active marrow and shallow marrow of the skeletal regions of the adult female. The bone macrostructure was obtained from the whole-body hybrid computational phantom of the UF series of reference phantoms, while the bone microstructure was derived from microCT images of skeletal region samples taken from a 45 year-old female cadaver. The target tissue regions were active marrow and shallow marrow. The source tissues were active marrow, inactive marrow, trabecular bone volume, trabecular bone surfaces, cortical bone volume and cortical bone surfaces. The marrow cellularity was varied from 10 to 100 percent for active marrow self-irradiation. A total of 33 discrete electron energies, ranging from 1 keV to 10 MeV, were either simulated or modeled analytically. Results: The method of combining macro- and microstructure absorbed fractions calculated using MCNPX electron transport was found to yield results similar to those determined with the PIRT model for the UF adult male in the Hough et al. study. Conclusion: The calculated skeletal averaged absorbed fractions for each source-target combination were found to follow similar trends of more recent dosimetry models (image-based models) and did not follow current models used in nuclear medicine dosimetry at high energies (due to that models use of an infinite expanse of trabecular spongiosa)

  3. What Is a Blood and Marrow Stem Cell Transplant?

    MedlinePlus

    ... procedure allows the recipient to get new stem cells that work properly. Stem cells are found in bone marrow, ... the body doesn't make enough red blood cells or they don't work properly. Certain immune-deficiency diseases that prevent the ...

  4. Bone marrow aspiration

    PubMed Central

    Bain, B

    2001-01-01

    Bone marrow aspiration biopsies are carried out principally to permit cytological assessment but also for immunophenotypic, cytogenetic, molecular genetic, and other specialised investigations. Often, a trephine biopsy is carried out as part of the same procedure. Bone marrow aspirations should be carried out by trained individuals who are aware of the indications, contraindications, and hazards of the procedure. They should follow a standard operating procedure. The operator should have made an adequate assessment of clinical and haematological features to ensure both that appropriate indications exist and that all relevant tests are performed. For the patient's comfort and safety, the posterior iliac crest is generally the preferred site of aspiration. Films of aspirated marrow and, when appropriate, films of crushed particles should be made and labelled. Once thoroughly dry, films should be fixed and stained. As a minimum, a Romanowsky stain and a Perls' stain are required. A cover slip should be applied. The bone marrow films should be assessed and reported in a systematic manner so that nothing of importance is overlooked, using a low power, then intermediate, then high power objective. A differential count should be performed. An interpretation of the findings, in the light of the clinical and haematological features, should be given. The report should be signed or computer authorised, using a secure password, and issued in a timely manner. Key Words: bone marrow aspirate • haematological diagnosis PMID:11533068

  5. Ion-kill dosimetry

    NASA Technical Reports Server (NTRS)

    Katz, R.; Cucinotta, F. A.; Fromm, M.; Chambaudet, A.

    2001-01-01

    Unanticipated late effects in neutron and heavy ion therapy, not attributable to overdose, imply a qualitative difference between low and high LET therapy. We identify that difference as 'ion kill', associated with the spectrum of z/beta in the radiation field, whose measurement we label 'ion-kill dosimetry'.

  6. Ion storage dosimetry

    NASA Astrophysics Data System (ADS)

    Mathur, V. K.

    2001-09-01

    The availability of a reliable, accurate and cost-effective real-time personnel dosimetry system is fascinating to radiation workers. Electronic dosimeters are contemplated to meet this demand of active dosimetry. The development of direct ion storage (DIS) dosimeters, a member of the electronic dosimeter family, for personnel dosimetry is also an attempt in this direction. DIS dosimeter is a hybrid of the well-established technology of ion chambers and the latest advances in data storage using metal oxide semiconductor field effect transistor (MOSFET) analog memory device. This dosimeter is capable of monitoring legal occupational radiation doses of gamma, X-rays, beta and neutron radiation. Similar to an ion chamber, the performance of the dosimeter for a particular application can be optimized through the selection of appropriate wall materials. The use of the floating gate of a MOSFET as one of the electrodes of the ion chamber allows the miniaturization of the device to the size of a dosimetry badge and avoids the use of power supplies during dose accumulation. The concept of the device, underlying physics and the design of the DIS dosimeter are discussed. The results of preliminary testing of the device are also provided.

  7. Dosimetry of Radiopharmaceuticals for Diagnostic and Therapeutic Nuclear Medicine

    SciTech Connect

    Smart, Richard

    2011-05-05

    A standard formalism for radionuclide internal radiation dosimetry was developed in the 1960s and continues to be refined today. Early work was based on a mathematical phantom but this is being replaced by phantoms developed from whole-body CT scans to give more realistic dose estimates. The largest contributors to the uncertainties in these dose estimates are the errors associated with in vivo activity quantitation, the variability of the biokinetics between patients and the limited information that can be obtained on these kinetics in individual patients. Despite these limitations, pre-treatment patient-specific dosimetry is being increasing used, particularly to limit the toxicity to non-target organs such as the bone marrow.

  8. Dosimetry of Radiopharmaceuticals for Diagnostic and Therapeutic Nuclear Medicine

    NASA Astrophysics Data System (ADS)

    Smart, Richard

    2011-05-01

    A standard formalism for radionuclide internal radiation dosimetry was developed in the 1960s and continues to be refined today. Early work was based on a mathematical phantom but this is being replaced by phantoms developed from whole-body CT scans to give more realistic dose estimates. The largest contributors to the uncertainties in these dose estimates are the errors associated with in vivo activity quantitation, the variability of the biokinetics between patients and the limited information that can be obtained on these kinetics in individual patients. Despite these limitations, pre-treatment patient-specific dosimetry is being increasing used, particularly to limit the toxicity to non-target organs such as the bone marrow.

  9. Bone-marrow transplant - slideshow

    MedlinePlus

    ... this page: //medlineplus.gov/ency/presentations/100112.htm Bone-marrow transplant - series—Normal anatomy To use the sharing ... Go to slide 4 out of 4 Overview Bone-marrow is a soft, fatty tissue found inside of ...

  10. Dosimetry for Radiopharmaceutical Therapy

    PubMed Central

    Sgouros, George; Hobbs, Robert F.

    2014-01-01

    Radiopharmaceutical therapy (RPT) involves the use of radionuclides that are either conjugated to tumor-targeting agents (eg, nanoscale constructs, antibodies, peptides, and small molecules) or concentrated in tissue through natural physiological mechanisms that occur predominantly in neoplastic or otherwise targeted cells (eg, Graves disease). The ability to collect pharmacokinetic data by imaging and use this to perform dosimetry calculations for treatment planning distinguishes RPT from other systemic treatment modalities. Treatment planning has not been widely adopted, in part, because early attempts to relate dosimetry to outcome were not successful. This was partially because a dosimetry methodology appropriate to risk evaluation rather than efficacy and toxicity was being applied to RPT. The weakest links in both diagnostic and therapeutic dosimetry are the accuracy of the input and the reliability of the radiobiological models used to convert dosimetric data to the relevant biologic end points. Dosimetry for RPT places a greater demand on both of these weak links. To date, most dosimetric studies have been retrospective, with a focus on tumor dose-response correlations rather than prospective treatment planning. In this regard, transarterial radioembolization also known as intra-arterial radiation therapy, which uses radiolabeled (90Y) microspheres of glass or resin to treat lesions in the liver holds much promise for more widespread dosimetric treatment planning. The recent interest in RPT with alpha-particle emitters has highlighted the need to adopt a dosimetry methodology that specifically accounts for the unique aspects of alpha particles. The short range of alpha-particle emitters means that in cases in which the distribution of activity is localized to specific functional components or cell types of an organ, the absorbed dose will be equally localized and dosimetric calculations on the scale of organs or even voxels (~5 mm) are no longer sufficient

  11. Aspiration and Biopsy: Bone Marrow

    MedlinePlus

    ... Help a Friend Who Cuts? Aspiration and Biopsy: Bone Marrow KidsHealth > For Teens > Aspiration and Biopsy: Bone Marrow Print A A A Text Size What's in ... Risks If You Have Questions What It Is Bone marrow aspirations and biopsies are performed to examine bone ...

  12. In vivo dosimetry for IMRT

    SciTech Connect

    Vial, Philip

    2011-05-05

    In vivo dosimetry has a well established role in the quality assurance of 2D radiotherapy and 3D conformal radiotherapy. The role of in vivo dosimetry for IMRT is not as well established. IMRT introduces a range of technical issues that complicate in vivo dosimetry. The first decade or so of IMRT implementation has largely relied upon pre-treatment phantom based dose verification. During that time, several new devices and techniques for in vivo dosimetry have emerged with the promise of providing the ultimate form of IMRT dose verification. Solid state dosimeters continue to dominate the field of in vivo dosimetry in the IMRT era. In this report we review the literature on in vivo dosimetry for IMRT, with an emphasis on clinical evidence for different detector types. We describe the pros and cons of different detectors and techniques in the IMRT setting and the roles that they are likely to play in the future.

  13. Quantitatively different red cell/nucleated cell chimerism in patients with long-term, persistent hematopoietic mixed chimerism after bone marrow transplantation for thalassemia major or sickle cell disease

    PubMed Central

    Andreani, Marco; Testi, Manuela; Gaziev, Javid; Condello, Rossella; Bontadini, Andrea; Tazzari, Pier Luigi; Ricci, Francesca; De Felice, Lidia; Agostini, Francesca; Fraboni, Daniela; Ferrari, Giuliana; Battarra, Mariarosa; Troiano, Maria; Sodani, Pietro; Lucarelli, Guido

    2011-01-01

    Background Persistent mixed chimerism represents a state in which recipient and donor cells stably co-exist after hematopoietic stem cell transplantation. However, since in most of the studies reported in literature the engraftment state was observed in the nucleated cells, in this study we determined the donor origin of the mature erythrocytes of patients with persistent mixed chimerism after transplantation for hemoglobinopathies. Results were compared with the engraftment state observed in singly picked out burst-forming unit – erythroid colonies and in the nucleated cells collected from the peripheral blood and from the bone marrow. Design and Methods The donor origin of the erythrocytes was determined analyzing differences on the surface antigens of the erythrocyte suspension after incubation with anti-ABO and/or anti-C, -c, -D, -E and -e monoclonal antibodies by a flow cytometer. Analysis of short tandem repeats was used to determine the donor origin of nucleated cells and burst-forming unit – erythroid colonies singly picked out after 14 days of incubation. Results The proportions of donor-derived nucleated cells in four transplanted patients affected by hemoglobinopathies were 71%, 46%, 15% and 25% at day 1364, 1385, 1314 and 932, respectively. Similar results were obtained for the erythroid precursors, analyzing the donor/recipient origin of the burst-forming unit – erythroid colonies. In contrast, on the same days of observation, the proportions of donor-derived erythrocytes in the four patients with persistent mixed chimerism were 100%, 100%, 73% and 90%. Conclusions Our results showed that most of the erythrocytes present in four long-term transplanted patients affected by hemoglobinopathies and characterized by the presence of few donor engrafted nucleated cells were of donor origin. The indication that small proportions of donor engrafted cells might be sufficient for clinical control of the disease in patients affected by hemoglobinopathies is

  14. Electron Paramagnetic Resonance Retrospective Dosimetry

    SciTech Connect

    Romanyukha, Alex; Trompier, Francois

    2011-05-05

    Necessity for, principles of, and general concepts of the electron paramagnetic resonance (EPR) retrospective dosimetry are presented. Also presented and given in details are examples of EPR retrospective dosimetry applications in tooth enamel, bone, and fingernails with focus on general approaches for solving technical and methodological problems. Advantages, drawbacks, and possible future developments are discussed and an extensive bibliography on EPR retrospective dosimetry is provided.

  15. Radiation dosimetry results from a Phase II trial of ibritumomab tiuxetan (Zevalin) radioimmunotherapy for patients with non-Hodgkin's lymphoma and mild thrombocytopenia.

    PubMed

    Wiseman, Gregory A; Leigh, Bryan R; Erwin, William D; Sparks, Richard B; Podoloff, Donald A; Schilder, Russell J; Bartlett, Nancy L; Spies, Stewart M; Grillo-López, Antonio J; Witzig, Thomas E; White, Christine A

    2003-04-01

    This was a 30-patient Phase II trial of reduced-dose (90)Y ibritumomab tiuxetan (Zevalin) RIT for patients with low-grade, follicular, or transformed B-cell NHL and mild thrombocytopenia. Patients were given an imaging dose of (111)In-labeled ibritumomab tiuxetan for dosimetry measurements. One week later, patients were administered a therapeutic dose of 0.3 mCi/kg (11 MBq/kg) (90)Y ibritumomab tiuxetan. Both (111)In- and (90)Y-labeled ibritumomab tiuxetan doses were preceded by an infusion of 250 mg/m(2) rituximab (Rituxan, MabThera) an unlabeled chimeric anti-CD20 antibody, to clear peripheral blood B cells and improve biodistribution of the radiolabeled antibody. For all 30 patients, normal organ and red marrow radiation absorbed doses were well below protocol-defined limits of 2000 cGy and 300 cGy, respectively. Median radiation absorbed doses were 48 cGy to red marrow (range: 6.5-95 cGy), 393 cGy to liver (range: 92-1581 cGy), 522 cGy to spleen (range: 165-1711 cGy), 162 cGy to lungs (41-295 cGy), and 14 cGy to kidneys (0.03-65 cGy). Though most correlative analyses were negative, certain analyses demonstrated a statistically significant correlation between the severity or duration of thrombocytopenia and pharmacokinetic or dosimetric parameters. These correlations were not consistent across the total patient population, and therefore, could not be exploited to predict hematologic toxicity. PMID:12804042

  16. Hanford External Dosimetry Program

    SciTech Connect

    Fix, J.J.

    1990-10-01

    This document describes the Hanford External Dosimetry Program as it is administered by Pacific Northwest Laboratory (PNL) in support of the US Department of Energy (DOE) and its Hanford contractors. Program services include administrating the Hanford personnel dosimeter processing program and ensuring that the related dosimeter data accurately reflect occupational dose received by Hanford personnel or visitors. Specific chapters of this report deal with the following subjects: personnel dosimetry organizations at Hanford and the associated DOE and contractor exposure guidelines; types, characteristics, and procurement of personnel dosimeters used at Hanford; personnel dosimeter identification, acceptance testing, accountability, and exchange; dosimeter processing and data recording practices; standard sources, calibration factors, and calibration processes (including algorithms) used for calibrating Hanford personnel dosimeters; system operating parameters required for assurance of dosimeter processing quality control; special dose evaluation methods applied for individuals under abnormal circumstances (i.e., lost results, etc.); and methods for evaluating personnel doses from nuclear accidents. 1 ref., 14 figs., 5 tabs.

  17. Neutron beam measurement dosimetry

    SciTech Connect

    Amaro, C.R.

    1995-11-01

    This report describes animal dosimetry studies and phantom measurements. During 1994, 12 dogs were irradiated at BMRR as part of a 4 fraction dose tolerance study. The animals were first infused with BSH and irradiated daily for 4 consecutive days. BNL irradiated 2 beagles as part of their dose tolerance study using BPA fructose. In addition, a dog at WSU was irradiated at BMRR after an infusion of BPA fructose. During 1994, the INEL BNCT dosimetry team measured neutron flux and gamma dose profiles in two phantoms exposed to the epithermal neutron beam at the BMRR. These measurements were performed as a preparatory step to the commencement of human clinical trials in progress at the BMRR.

  18. Prostate PDT dosimetry

    PubMed Central

    Zhu, Timothy C.; Finlay, Jarod C.

    2015-01-01

    Summary We provide a review of the current state of dosimetry in prostate photodynamic therapy (PDT). PDT of the human prostate has been performed with a number of different photosensitizers and with a variety of dosimetry schemes. The simplest clinical light dose prescription is to quantify the total light energy emitted per length (J/cm) of cylindrical diffusing fibers (CDF) for patients treated with a defined photosensitizer injection per body weight. However, this approach does not take into account the light scattering by tissue and usually underestimates the local light fluence rate, and consequently the fluence. Techniques have been developed to characterize tissue optical properties and light fluence rates in vivo using interstitial measurements during prostate PDT. Optical methods have been developed to characterize tissue absorption and scattering spectra, which in turn provide information about tissue oxygenation and drug concentration. Fluorescence techniques can be used to quantify drug concentrations and photobleaching rates of photosensitizers. PMID:25046988

  19. Cosmic Ray Dosimetry

    NASA Astrophysics Data System (ADS)

    Si Belkhir, F.; Attallah, R.

    2010-10-01

    Radiation levels at aircraft cruising altitudes are twenty times higher than at sea level. Thus, on average, a typical airline pilot receives a larger annual radiation dose than some one working in nuclear industry. The main source of this radiation is from galactic cosmic radiation, high energy particles generated by exploding stars within our own galaxy. In this work we study cosmic rays dosimetry at various aviation altitudes using the PARMA model.

  20. Orchiectomy increases bone marrow interleukin-6 levels in mice.

    PubMed

    Zhang, J; Pugh, T D; Stebler, B; Ershler, W B; Keller, E T

    1998-03-01

    Interleukin-6 (IL-6) appears to be an important factor in disease states associated with bone resorption. There is both in vitro and in vivo evidence supporting the fact that androgens down-regulate interleukin-6 production. These observations, in combination with the fact that osteoblasts and bone marrow stromal cells produce IL-6, led us to hypothesize that orchiectomy-induced androgen loss will result in increased IL-6 expression in the bone microenvironment. To prove our hypothesis we assessed the effect of orchiectomy on IL-6 protein and mRNA expression in bone marrow and spleen. We found that orchiectomy was associated with increased serum IL-6 levels at 3 and 28 days postsurgery. Phorbol ester-stimulated IL-6 levels were also higher in supernatants from bone marrow and spleen cell cultures from orchiectomized mice compared with unoperated or sham-operated mice. Additionally, we found that steady state IL-6 mRNA levels were increased in bone marrow but not spleen cells. Finally, we found that orchiectomized mice had splenomegaly and increased bone marrow cellularity. Histopathology of the spleen revealed lymphoid hyperplasia accompanied by a marked mononuclear cell infiltration of the red pulp. We conclude that orchiectomy induces IL-6 expression in the bone marrow. These findings suggest that endocrine and cytokine interactions contribute to bone pathophysiology. PMID:9501955

  1. Pharmacokinetic, Dosimetry and Toxicity Study of ¹⁷⁷Lu-EDTMP in Patients: Phase 0/I study.

    PubMed

    Bal, Chandrasekhar; Arora, Geetanjali; Kumar, Praveen; Damle, Nishikant; Das, Tapas; Chakraborty, Sudipta; Banerjee, Sharmila; Venkatesh, Meera; Zaknun, John J; Pillai, M R A

    2016-01-01

    177Lu-EDTMP has been proposed as a potent bone pain palliation agent owing to theoretical advantage of reduced bone marrow suppression resulting from the low β(-) energy and a suitably long half-life facilitating its wider distribution with less loss from radioactive decay. Herein, we report the pharmacokinetics, dosimetry and toxicity analysis of 177Lu-EDTMP in patients (phase-0/I study). In a phase-0 study, the biokinetics of skeletal and non-skeletal uptake of 177Lu-EDTMP was assessed in 6 patients with metastatic prostate cancer using tracer doses (172.7-206.9MBq). Data of whole skeletal uptake, blood and fractionated urine samples were obtained and dosimetric calculations were performed using the OLINDA/EXM 1.0 software. Prolonged bone retention was observed in all patients. Excretion was mainly via the renal route and blood clearance was rapid and biphasic. Mean estimated red marrow dose was 0.80±0.15mGy/MBq while mean total-body dose was 0.16±0.04mGy/MBq. A maximum tolerated dose (MTD) of 2000-3250MBqfor 177Lu-EDTMP was calculated. For the phase-I study, 21 patients with metastatic prostate cancer were given a therapeutic dose of 177Lu- EDTMP (692-5550MBq). Toxiciy (WHO), evaluated by assessment of hemoglobin levels, platelet and leukocyte counts over 12 weeks, was mainly limited to anemia or thrombocytopenia. Only transient toxicity was observed in 14/21 patients, of which 6 had baseline toxicity. Beyond the MTD, a significantly higher number of patients displayed grade 3-4 toxicity. Pain relief, assessed by VAS pain score, was observed in 86% patients with median relief duration of 7 weeks. The results demonstrate that 177Lu-EDTMP has excellent pharmacokinetic and dosimetric properties, besides being safe and effective. Along with estimating radiation dose values to certain critical organs, we have also proposed an MTD for 177Lu-EDTMP that correlated well with toxicity data. The encouraging dosimetry and toxicity data of 177Lu-EDTMP reported provide the

  2. Skeletal dosimetry models for alpha-particles for use in molecular radiotherapy

    NASA Astrophysics Data System (ADS)

    Watchman, Christopher J.

    Molecular radiotherapy is a cancer treatment methodology whereby a radionuclide is combined with a biologically active molecule to preferentially target cancer cells. Alpha-particle emitting radionuclides show significant potential for use in molecular radiotherapy due to the short range of the alpha-particles in tissue and their high rates of energy deposition. Current radiation dosimetry models used to assess alpha emitter dose in the skeleton were developed originally for occupational applications. In medical dosimetry, individual variability in uptake, translocation and other biological factors can result in poor correlation of clinical outcome with marrow dose estimates determined using existing skeletal models. Methods presented in this work were developed in response to the need for dosimetry models which account for these biological and patient-specific factors. Dosimetry models are presented for trabecular bone alpha particle dosimetry as well as a model for cortical bone dosimetry. These radiation transport models are the 3D chord-based infinite spongiosa transport model (3D-CBIST) and the chord-based infinite cortical transport model (CBICT), respectively. Absorbed fraction data for several skeletal tissues for several subjects are presented. Each modeling strategy accounts for biological parameters, such as bone marrow cellularity, not previously incorporated into alpha-particle skeletal dosimetry models used in radiation protection. Using these data a study investigating the variability in alpha-particle absorbed fractions in the human skeleton is also presented. Data is also offered relating skeletal tissue masses in individual bone sites for a range of ages. These data are necessary for dose calculations and have previously only been available as whole body tissue masses. A revised 3D-CBIST model is also presented which allows for changes in endosteum thickness to account for revised target cell location of tissues involved in the radiological

  3. The International Reactor Dosimetry File.

    Energy Science and Technology Software Center (ESTSC)

    1994-01-19

    Version 01 The International Reactor Dosimetry File (IRDF-90) contains recommended neutron cross-section data to be used for reactor neutron dosimetry by foil activation. It also contains selected recommended values for radiation damage cross-sections and benchmark neutron spectra. This library supersedes all earlier versions of IRDF.

  4. Surface area overestimation within three-dimensional digital images and its consequence for skeletal dosimetry.

    PubMed

    Rajon, D A; Patton, P W; Shah, A P; Watchman, C J; Bolch, W E

    2002-05-01

    The most recent methods for trabecular bone dosimetry are based on Monte Carlo transport simulations within three-dimensional (3D) images of real human bone samples. Nuclear magnetic resonance and micro-computed tomography have been commonly used as imaging tools for studying trabecular microstructure. In order to evaluate the accuracy of these techniques for radiation dosimetry, a previous study was conducted that showed an overestimate in the absorbed fraction of energy for low-energy electrons emitted within the marrow space and irradiating the bone trabeculae. This problem was found to be related to an overestimate of the surface area of the true bone-marrow interface within the 3D digital images, and was identified as the surface-area effect. The goal of the present study is to better understand how this surface-area effect occurs in the case of single spheres representing individual marrow cavities within trabecular bone. First, a theoretical study was conducted which showed that voxelization of the spherical marrow cavity results in a 50% overestimation of the spherical surface area. Moreover, this overestimation cannot be reduced through a reduction in the voxel size (e.g., improved image resolution). Second, a series of single-sphere marrow cavity models was created with electron sources simulated within the sphere (marrow source) and outside the sphere (bone trabeculae source). The series of single-sphere models was then voxelized to represent 3D digital images of varying resolution. Transport calculations were made for both marrow and bone electron sources within these simulated images. The study showed that for low-energy electrons (<100 keV), the 50% overestimate of the bone-marrow interface surface area can lead to a 50% overestimate of the cross-absorbed fraction. It is concluded that while improved resolution will not reduce the surface area effects found within 3D image-based transport models, a tenfold improvement in current image resolution would

  5. Eye redness

    MedlinePlus

    Bloodshot eyes; Red eyes; Scleral infection; Conjunctival infection ... There are many causes of a red eye or eyes. Some are medical emergencies and some are a cause for concern, but not an emergency. Others are nothing to worry about. ...

  6. Red Clover

    MedlinePlus

    ... 17):2057–2071. Red clover. Natural Medicines Comprehensive Database Web site. Accessed at www.naturaldatabase.com on July 22, 2009. Red clover ( Trifolium pratense ). Natural Standard Database Web site. Accessed at www.naturalstandard.com on July ...

  7. Bone marrow trephine biopsy

    PubMed Central

    Bain, B

    2001-01-01

    Trephine biopsies of the bone marrow should be carried out, when clinically indicated, by trained individuals following a standard operating procedure. A bone marrow aspiration should be performed as part of the same procedure. For patient safety and convenience, biopsies are usually performed on the posterior iliac crest. The biopsy specimen should measure at least 1.6 cm and, if it does not, consideration should be given to repeating the procedure, possibly on the contralateral iliac crest. If bone marrow aspiration is found to be impossible, imprints from the biopsy specimen should be obtained. Otherwise, the specimen is placed immediately into fixative and after fixation is embedded in a resin or, more usually, decalcified and embedded in paraffin wax. Thin sections are cut and are stained, as a minimum, with haematoxylin and eosin and with a reticulin stain. A Giemsa stain is also desirable. A Perls' stain does not often give useful information and is not essential in every patient. The need for other histochemical or immunohistochemical stains is determined by the clinical circumstances and the preliminary findings. Trephine biopsy sections should be examined and reported in a systematic manner, assessment being made of the bones, the vessels and stroma, and the haemopoietic and any lymphoid or other tissue. Assessment should begin with a very low power objective, the entire section being examined. Further examination is then done with an intermediate and high power objective. Ideally, reporting of trephine biopsy sections should be done by an individual who is competent in both histopathology and haematology, and who is able to make an appropriate assessment of both the bone marrow aspirate and the trephine biopsy sections. When this is not possible, there should be close consultation between a haematologist and a histopathologist. The report should both describe the histological findings and give an interpretation of their importance. A signed or computer

  8. Bone marrow invasion in multiple myeloma and metastatic disease.

    PubMed

    Vilanova, J C; Luna, A

    2016-04-01

    Magnetic resonance imaging (MRI) of the spine is the imaging study of choice for the management of bone marrow disease. MRI sequences enable us to integrate structural and functional information for detecting, staging, and monitoring the response the treatment of multiple myeloma and bone metastases in the spine. Whole-body MRI has been incorporated into different guidelines as the technique of choice for managing multiple myeloma and metastatic bone disease. Normal physiological changes in the yellow and red bone marrow represent a challenge in analyses to differentiate clinically significant findings from those that are not clinically significant. This article describes the findings for normal bone marrow, variants, and invasive processes in multiple myeloma and bone metastases. PMID:26767542

  9. Heavy-ion dosimetry

    SciTech Connect

    Schimmerling, W.

    1980-03-01

    This lecture deals with some of the more important physical characteristics of relativistic heavy ions and their measurement, with beam delivery and beam monitoring, and with conventional radiation dosimetry as used in the operation of the BEVALAC biomedical facility for high energy heavy ions (Lyman and Howard, 1977; BEVALAC, 1977). Even so, many fundamental aspects of the interaction of relativistic heavy ions with matter, including important atomic physics and radiation chemical considerations, are not discussed beyond the reminder that such additional understanding is required before an adequte perspective of the problem can be attained.

  10. Uranium Dispersion & Dosimetry Model.

    SciTech Connect

    MICHAEL,; MOMENI, H.

    2002-03-22

    The Uranium Dispersion and Dosimetry (UDAD) program provides estimates of potential radiation exposure to individuals and to the general population in the vicinity of a uranium processing facility such as a uranium mine or mill. Only transport through the air is considered. Exposure results from inhalation, external irradiation from airborne and ground-deposited activity, and ingestion of foodstuffs. Individual dose commitments, population dose commitments, and environmental dose commitments are computed. The program was developed for application to uranium mining and milling; however, it may be applied to dispersion of any other pollutant.

  11. Fast neutron dosimetry

    SciTech Connect

    DeLuca, P.M. Jr.; Pearson, D.W.

    1992-01-01

    This progress report concentrates on two major areas of dosimetry research: measurement of fast neutron kerma factors for several elements for monochromatic and white spectrum neutron fields and determination of the response of thermoluminescent phosphors to various ultra-soft X-ray energies and beta-rays. Dr. Zhixin Zhou from the Shanghai Institute of Radiation Medicine, People's Republic of China brought with him special expertise in the fabrication and use of ultra-thin TLD materials. Such materials are not available in the USA. The rather unique properties of these materials were investigated during this grant period.

  12. Uranium Dispersion & Dosimetry Model.

    Energy Science and Technology Software Center (ESTSC)

    2002-03-22

    The Uranium Dispersion and Dosimetry (UDAD) program provides estimates of potential radiation exposure to individuals and to the general population in the vicinity of a uranium processing facility such as a uranium mine or mill. Only transport through the air is considered. Exposure results from inhalation, external irradiation from airborne and ground-deposited activity, and ingestion of foodstuffs. Individual dose commitments, population dose commitments, and environmental dose commitments are computed. The program was developed for applicationmore » to uranium mining and milling; however, it may be applied to dispersion of any other pollutant.« less

  13. The Utah Leukemia Case-Control Study: dosimetry methodology and results.

    PubMed

    Simon, S L; Till, J E; Lloyd, R D; Kerber, R L; Thomas, D C; Preston-Martin, S; Lyon, J L; Stevens, W

    1995-04-01

    This paper discusses the dosimetry methodology used to estimate bone marrow dose and the results of dosimetry calculations for 6,507 subjects in an epidemiologic case-control study of leukemia among Utah residents. The estimated doses were used to determine if a higher incidence of leukemia among residents of Utah could have been attributed to exposure to radioactive fallout from above-ground nuclear weapons tests conducted at the Nevada Test Site. The objective of the dosimetry methodology was to estimate absorbed dose to active marrow specific to each case and each control subject. Data on the residence of each subject were available from records of the Church of Jesus Christ of Latter-day Saints. Deposition of fallout was determined from databases developed using historical measurements and exposure for each subject from each test was estimated using those data. Exposure was converted to dose by applying an age-dependent dose conversion factor and a factor for shielding. The median dose for all case and control subjects was 3.2 mGy. The maximum estimated mean dose for any case or control was 29 +/- 5.6 mGy (a resident of Washington County, UT). Uncertainties were estimated for each estimated dose. The results of the dosimetry calculations were applied in an epidemiological analysis. PMID:7883558

  14. Red clover

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Red clover (Trifolium pratense L.) is an important forage legume grown on approximately 4 million hectares worldwide. An estimated 2.8 million kg of red clover seed per year was produced worldwide in 2005-2007. This amount of seed would be enough to maintain approximately 4 million hectares of red...

  15. Red Sea

    Atmospheric Science Data Center

    2013-04-16

    article title:  The Red Sea     View Larger Image ... Imaging SpectroRadiometer (MISR) image of the Red Sea was acquired on August 13, 2000. Located between the East African coast and the Saudi Arabian peninsula, the Red Sea got its name because the blooms of a type of algae,  Trichodesmium ...

  16. Hematopoietic bone marrow in the adult knee: spin-echo and opposed-phase gradient-echo MR imaging.

    PubMed

    Lang, P; Fritz, R; Majumdar, S; Vahlensieck, M; Peterfy, C; Genant, H K

    1993-01-01

    Hematopoietic bone marrow in the distal femur of the adult may be mistaken for a pathologic marrow process in magnetic resonance imaging of the knee. We investigated the incidence of hematopoietic marrow in the distal femur in a series of 51 adult patients and compared spin-echo (TR/TE in ms: 500/35, 2000/80) and opposed-phase gradient-echo (0.35 T, TR/TE in ms: 1000/30, theta = 75 degrees) magnetic resonance images. Zones with intermediate to low signal intensity on T1-weighted spin-echo and opposed-phase gradient-echo sequences representing hematopoietic marrow within high signal intensity fatty marrow were observed in 18 of the 51 patients. Five patterns of marrow signal reduction were identified; type 0: uniform high signal, i.e., no signal change; type I, focal signal loss; type II, multifocal signal loss without confluence; type III, confluent signal loss; and type IV, complete homogeneous reduction in marrow signal. Opposed-phase gradient-echo sequences demonstrated markedly greater red-yellow marrow contrast than conventional spin-echo sequences. Follow-up studies in three patients using a gradient-echo sequence with TE varying from 10 to 21 ms at 1-ms increments showed a cyclic increase and decrease in red and yellow marrow signal intensity depending on the TE. The contribution of intravoxel chemical shift effects on red-yellow marrow contrast in opposed-phase gradient-echo images was verified by almost complete cancellation of the TE-dependent marrow signal oscillation with use of a chemically selective pulse presaturating the water protons. Hematopoietic marrow in the adult distal femur in the absence of hematologic abnormalities is found primarily in women of menstruating age.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8438189

  17. Liquid radiochromic dosimetry

    NASA Astrophysics Data System (ADS)

    Rativanich, N.; Radak, B. B.; Miller, A.; Uribe, R. M.; McLaughlin, W. L.

    By strategic combination of weak acid, mild oxidizing agent, and polar organic solvents containing millimolar concentrations of leucocyanides of certain triphenylmethane dyes, fairly broad ranges of absorbed doses of ionizing radiation can be determined. The yield of dye ions as determined by spectrophotometry can be made essentially constant with dose (i.e. linear response) from 0.01 to 30 kGy and it does not vary with dose rate upto 10 11 Gy·s -1. The radiation-induced color is stable and offers fast-retrieval dosimetry if N-vinyl-2-pyrrolidone is used as solvent. Other possible polar solvents are 2-propanol, 2-methoxy ethanol, N, N-dimethyl formamide, dimethyl sulfoxide, and triethyl phosphate. Dimethyl sulfoxide is found to give the widest and most linear response. Suitable dye precursors are leucocyanides of pararosaniline, new fuchsin, hexa (hydroxyethyl) pararosaniline, crystal violet, malachite green, setoglaucine, ethyl violet, helvetia green, basic violet-14, and formyl violet. Low concentrations of carboxylic acids contribute stability to the system. Typical mild oxidizing agents are nitrobenzene, and atmospheric oxygen, or oxygen released radiolytically from the solvents. The dosimetry systems do not require high-purity of ingredients or ultracleanliness of containers, although, for reproducibility of dye yields (G-values), thoroughly purified and uniform dye derivates are recommended.

  18. TOPICAL REVIEW: Polymer gel dosimetry

    NASA Astrophysics Data System (ADS)

    Baldock, C.; De Deene, Y.; Doran, S.; Ibbott, G.; Jirasek, A.; Lepage, M.; McAuley, K. B.; Oldham, M.; Schreiner, L. J.

    2010-03-01

    Polymer gel dosimeters are fabricated from radiation sensitive chemicals which, upon irradiation, polymerize as a function of the absorbed radiation dose. These gel dosimeters, with the capacity to uniquely record the radiation dose distribution in three-dimensions (3D), have specific advantages when compared to one-dimensional dosimeters, such as ion chambers, and two-dimensional dosimeters, such as film. These advantages are particularly significant in dosimetry situations where steep dose gradients exist such as in intensity-modulated radiation therapy (IMRT) and stereotactic radiosurgery. Polymer gel dosimeters also have specific advantages for brachytherapy dosimetry. Potential dosimetry applications include those for low-energy x-rays, high-linear energy transfer (LET) and proton therapy, radionuclide and boron capture neutron therapy dosimetries. These 3D dosimeters are radiologically soft-tissue equivalent with properties that may be modified depending on the application. The 3D radiation dose distribution in polymer gel dosimeters may be imaged using magnetic resonance imaging (MRI), optical-computerized tomography (optical-CT), x-ray CT or ultrasound. The fundamental science underpinning polymer gel dosimetry is reviewed along with the various evaluation techniques. Clinical dosimetry applications of polymer gel dosimetry are also presented.

  19. Topical Review: Polymer gel dosimetry

    PubMed Central

    Baldock, C; De Deene, Y; Doran, S; Ibbott, G; Jirasek, A; Lepage, M; McAuley, K B; Oldham, M; Schreiner, L J

    2010-01-01

    Polymer gel dosimeters are fabricated from radiation sensitive chemicals which, upon irradiation, polymerize as a function of the absorbed radiation dose. These gel dosimeters, with the capacity to uniquely record the radiation dose distribution in three-dimensions (3D), have specific advantages when compared to one-dimensional dosimeters, such as ion chambers, and two-dimensional dosimeters, such as film. These advantages are particularly significant in dosimetry situations where steep dose gradients exist such as in intensity-modulated radiation therapy (IMRT) and stereotactic radiosurgery. Polymer gel dosimeters also have specific advantages for brachytherapy dosimetry. Potential dosimetry applications include those for low-energy x-rays, high-linear energy transfer (LET) and proton therapy, radionuclide and boron capture neutron therapy dosimetries. These 3D dosimeters are radiologically soft-tissue equivalent with properties that may be modified depending on the application. The 3D radiation dose distribution in polymer gel dosimeters may be imaged using magnetic resonance imaging (MRI), optical-computerized tomography (optical-CT), x-ray CT or ultrasound. The fundamental science underpinning polymer gel dosimetry is reviewed along with the various evaluation techniques. Clinical dosimetry applications of polymer gel dosimetry are also presented. PMID:20150687

  20. Optimizing the dynamic range extension of a radiochromic film dosimetry system

    SciTech Connect

    Devic, Slobodan; Tomic, Nada; Soares, Christopher G.; Podgorsak, Ervin B.

    2009-02-15

    The authors present a radiochromic film dosimetry protocol for a multicolor channel radiochromic film dosimetry system consisting of the external beam therapy (EBT) model GAFCHROMIC film and the Epson Expression 1680 flat-bed document scanner. Instead of extracting only the red color channel, the authors are using all three color channels in the absorption spectrum of the EBT film to extend the dynamic dose range of the radiochromic film dosimetry system. By optimizing the dose range for each color channel, they obtained a system that has both precision and accuracy below 1.5%, and the optimized ranges are 0-4 Gy for the red channel, 4-50 Gy for the green channel, and above 50 Gy for the blue channel.

  1. High-fidelity organic preservation of bone marrow in ca. 10 Ma amphibians

    NASA Astrophysics Data System (ADS)

    McNamara, Maria E.; Orr, Patrick J.; Kearns, Stuart L.; Alcalá, Luis; Anadón, Pere; Peñalver-Mollá, Enrique

    2006-08-01

    Bone marrow in ca. 10 Ma frogs and salamanders from the Miocene of Libros, Spain, represents the first fossilized example of this extremely decay-prone tissue. The bone marrow, preserved in three dimensions as an organic residue, retains the original texture and red and yellow color of hematopoietic and fatty marrow, respectively; moldic osteoclasts and vascular structures are also present. We attribute exceptional preservation of the fossilized bone marrow to cryptic preservation: the bones of the amphibians formed protective microenvironments, and inhibited microbial infiltration. Specimens in which bone marrow is preserved vary in their completeness and articulation and in the extent to which the body outline is preserved as a thin film of organically preserved bacteria. Cryptic preservation of these labile tissues is thus to a large extent independent of, and cannot be predicted by, the taphonomic history of the remainder of the specimen.

  2. Starvation marrow – gelatinous transformation of bone marrow

    PubMed Central

    Osgood, Eric; Muddassir, Salman; Jaju, Minal; Moser, Robert; Farid, Farwa; Mewada, Nishith

    2014-01-01

    Gelatinous bone marrow transformation (GMT), also known as starvation marrow, represents a rare pathological entity of unclear etiology, in which bone marrow histopathology demonstrates hypoplasia, fat atrophy, and gelatinous infiltration. The finding of gelatinous marrow transformation lacks disease specificity; rather, it is an indicator of severe illness and a marker of poor nutritional status, found in patients with eating disorders, acute febrile illnesses, acquired immunodeficiency syndrome, alcoholism, malignancies, and congestive heart failure. We present a middle-aged woman with a history of alcoholism, depression, and anorexia nervosa who presented with failure to thrive and macrocytic anemia, with bone marrow examination demonstrative of gelatinous transformation, all of which resolved with appropriate treatment. To our knowledge, there are very few cases of GMT which have been successfully treated; thus, our case highlights the importance of proper supportive management. PMID:25317270

  3. KSC CENTER DIRECTOR ACCEPTS PLAQUE FOR RECORD-SETTING BONE MARROW DONOR REGISTRATION DRIVE

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Kennedy Space Center's Bone Marrow Donor Registration Drive Chairman Dr. George A. Martin and Center Director Jay Honeycutt (left to right) accept a plaque from the Leukemia Society of America's Associate Executive Director Martin Bernstine and the American Red Cross' Southeast Regional Director Jeff Koenreich. Representatives from the American Red Cross and the Leukemia Society of America came to KSC to honor those involved in the record-setting Bone Marrow Donor Registration Drive held here earlier this year. Over 900 potential donors were added to the National Bone Marrow Registry as a result of the KSC drive. The drive established a new record for the most people registered in a single day for the American Red Cross in the three state region of which Florida is a part.

  4. Bone Marrow Derived Eosinophil Cultures

    PubMed Central

    Lu, Thomas X.; Rothenberg, Marc E.

    2016-01-01

    Eosinophils are multifunctional effector cells implicated in the pathogenesis of a variety of diseases including asthma, eosinophil gastrointestinal disorders and helminth infection. Mouse bone marrow derived progenitor cells can be differentiated into eosinophils following IL-5 exposure. These bone marrow derived eosinophils are fully differentiated at the end of a 14 day culture based on morphology and expression of molecular markers.

  5. A Dosimetric Study of Radionuclide Therapy for Bone Marrow Ablation.

    NASA Astrophysics Data System (ADS)

    Bayouth, John Ellis

    In a phase I clinical trial, six multiple myeloma patients, who were non-responsive to conventional therapy and were scheduled for bone marrow transplantation, received Holmium-166 (166Ho) labeled to a bone seeking agent, DOTMP (1,4,7,10-tetraazacyclododecane -1,4,7,10-tetramethylene-phosphonic acid), for the purpose of bone marrow ablation. The specific aims of my research within this protocol were to evaluate the toxicity and efficacy of 166Ho DOTMP by quantifying the in vivo pharmacokinetics and radiation dosimetry, and by correlating these results to the biologic response observed. The reproducibility of pharmacokinetics from multiple injections of 166 Ho DOTMP administered to these myeloma patients was demonstrated from both blood and whole body retention. The skeletal concentration of 166 Ho DOTMP was heterogenous in all six patients: high in the ribs, pelvis, and lumbar vertebrae regions, and relatively low in the femurs, arms, and head. A novel technique was developed to calculate the radiation dose to the bone marrow in each skeletal ROI, and was applied to all six 166 Ho DOTMP patients. Radiation dose estimates for the bone marrow calculated using the standard MIRD "S" factors were compared with the average values derived from the heterogenous distribution of activity in the skeleton (i.e., the regional technique). The results from the two techniques were significantly different; the average of the dose estimates from the regional technique were typically 30% greater. Furthermore, the regional technique provided a range of radiation doses for the entire marrow volume, while the MIRD "S" factors only provided a single value. Dose volume histogram analysis of data from the regional technique indicated a range of dose estimates that varied by a factor of 10 between the high dose and low dose regions. Finally, the observed clinical response of cells and abnormal proteins measured in bone marrow aspirates and peripheral blood samples were compared with

  6. Internal dosimetry technical basis manual

    SciTech Connect

    Not Available

    1990-12-20

    The internal dosimetry program at the Savannah River Site (SRS) consists of radiation protection programs and activities used to detect and evaluate intakes of radioactive material by radiation workers. Examples of such programs are: air monitoring; surface contamination monitoring; personal contamination surveys; radiobioassay; and dose assessment. The objectives of the internal dosimetry program are to demonstrate that the workplace is under control and that workers are not being exposed to radioactive material, and to detect and assess inadvertent intakes in the workplace. The Savannah River Site Internal Dosimetry Technical Basis Manual (TBM) is intended to provide a technical and philosophical discussion of the radiobioassay and dose assessment aspects of the internal dosimetry program. Detailed information on air, surface, and personal contamination surveillance programs is not given in this manual except for how these programs interface with routine and special bioassay programs.

  7. Radioembolization Dosimetry: The Road Ahead

    SciTech Connect

    Smits, Maarten L. J. Elschot, Mattijs; Sze, Daniel Y.; Kao, Yung H.; Nijsen, Johannes F. W.; Iagaru, Andre H.; Jong, Hugo W. A. M. de; Bosch, Maurice A. A. J. van den; Lam, Marnix G. E. H.

    2015-04-15

    Methods for calculating the activity to be administered during yttrium-90 radioembolization (RE) are largely based on empirical toxicity and efficacy analyses, rather than dosimetry. At the same time, it is recognized that treatment planning based on proper dosimetry is of vital importance for the optimization of the results of RE. The heterogeneous and often clustered intrahepatic biodistribution of millions of point-source radioactive particles poses a challenge for dosimetry. Several studies found a relationship between absorbed doses and treatment outcome, with regard to both toxicity and efficacy. This should ultimately lead to improved patient selection and individualized treatment planning. New calculation methods and imaging techniques and a new generation of microspheres for image-guided RE will all contribute to these improvements. The aim of this review is to give insight into the latest and most important developments in RE dosimetry and to suggest future directions on patient selection, individualized treatment planning, and study designs.

  8. Medical dosimetry in Hungary

    NASA Astrophysics Data System (ADS)

    Turák, O.; Osvay, M.; Ballay, L.

    2012-09-01

    Radiation exposure of medical staff during cardiological and radiological procedures was investigated. The exposure of medical staff is directly connected to patient exposure. The aim of this study was to determine the distribution of doses on uncovered part of body of medical staff using LiF thermoluminescent (TL) dosimeters in seven locations. Individual Kodak film dosimeters (as authorized dosimetry system) were used for the assessment of medical staff's effective dose. Results achieved on dose distribution measurements confirm that wearing only one film badge under the lead apron does not provide enough information on the personal dose. The value of estimated annual doses on eye lens and extremities (fingers) were in good correlation with international publications.

  9. Fundamentals of Radiation Dosimetry

    SciTech Connect

    Bos, Adrie J. J.

    2011-05-05

    The basic concepts of radiation dosimetry are reviewed on basis of ICRU reports and text books. The radiation field is described with, among others, the particle fluence. Cross sections for indirectly ionizing radiation are defined and indicated is how they are related to the mass energy transfer and mass energy absorption coefficients. Definitions of total and restricted mass stopping powers of directly ionizing radiation are given. The dosimetric quantities, kerma, absorbed dose and exposure together with the relations between them are discussed in depth. Finally it is indicated how the absorbed dose can be measured with a calorimeter by measuring the temperature increase and with an ionisation chamber measuring the charge produced by the ionizing radiation and making use of the Bragg-Gray relation.

  10. Fundamentals of Radiation Dosimetry

    NASA Astrophysics Data System (ADS)

    Bos, Adrie J. J.

    2011-05-01

    The basic concepts of radiation dosimetry are reviewed on basis of ICRU reports and text books. The radiation field is described with, among others, the particle fluence. Cross sections for indirectly ionizing radiation are defined and indicated is how they are related to the mass energy transfer and mass energy absorption coefficients. Definitions of total and restricted mass stopping powers of directly ionizing radiation are given. The dosimetric quantities, kerma, absorbed dose and exposure together with the relations between them are discussed in depth. Finally it is indicated how the absorbed dose can be measured with a calorimeter by measuring the temperature increase and with an ionisation chamber measuring the charge produced by the ionizing radiation and making use of the Bragg-Gray relation.

  11. Laser heated thermoluminescence dosimetry

    SciTech Connect

    Justus, B.L.; Huston, A.L.

    1996-06-01

    We report a novel laser-heated thermoluminescence dosimeter that is radically different from previous laser-heated dosimeters. The dosimeter is a semiconductor and metal ion doped silica glass that has excellent optical transparency. The high optical quality of the glass essentially eliminates laser power loss due to light scattering. This efficient utilization of the laser power permits operation of the dosimeter without strong absorption of the laser, as is required in traditional laser-heated dosimetry. Our laser-heated dosimeter does not rely on the diffusion of heat from a separate, highly absorbing substrate, but operates via intimate, localized heating within the glass dosimeter due to the absorption of the laser light by rare earth ion dopants in the glass. Following absorption of the laser light, the rare earth ions transfer energy to the surrounding glass via nonradiative relaxation processes, resulting in rapid, localized temperature increases sufficient to release all the filled traps near the ions. As the heat diffuses radially away from the rare earth ions the temperature plummets dramatically on a manometer distance scale and the release of additional filled traps subsides. A key distinguishing feature of this laser-heated dosimeter is the ability to read the dose information more than once. While laser-heating provides complete information about the radiation exposure experienced by the glass due to the release of locally heated traps, the process leaves the remaining filled bulk traps undisturbed. The bulk traps can be read using traditional bulk heating methods and can provide a direct determination of an accumulated dose, measured following any number of laser-heated readouts. Laser-heated dosimetry measurements have been performed using a solid state diode laser for the readout following radiation exposure with a {sup 60}Co source.

  12. Fifth international radiopharmaceutical dosimetry symposium

    SciTech Connect

    Watson, E.E.; Schlafke-Stelson, A.T.

    1992-05-01

    This meeting was held to exchange information on how to get better estimates of the radiation absorbed dose. There seems to be a high interest of late in patient dosimetry; discussions were held in the light of revised risk estimates for radiation. Topics included: Strategies of Dose Assessment; Dose Estimation for Radioimmunotherapy; Dose Calculation Techniques and Models; Dose Estimation for Positron Emission Tomography (PET); Kinetics for Dose Estimation; and Small Scale Dosimetry and Microdosimetry. (VC)

  13. The International Reactor Dosimetry File.

    Energy Science and Technology Software Center (ESTSC)

    2008-08-07

    Version 01 The International Reactor Dosimetry File (IRDF-2002) contains recommended neutron cross-section data to be used for reactor neutron dosimetry by foil activation and subsequent neutron spectrum unfolding. It also contains selected recom�mended values for radiation damage cross-sections and benchmark neutron spectra. Two related programs available from NEADB and RSICC are: SPECTER-ANL (PSR-263) & STAY’SL (PSR-113).

  14. Hanford internal dosimetry program manual

    SciTech Connect

    Carbaugh, E.H.; Sula, M.J.; Bihl, D.E.; Aldridge, T.L.

    1989-10-01

    This document describes the Hanford Internal Dosimetry program. Program Services include administrating the bioassay monitoring program, evaluating and documenting assessments of internal exposure and dose, ensuring that analytical laboratories conform to requirements, selecting and applying appropriate models and procedures for evaluating internal radionuclide deposition and the resulting dose, and technically guiding and supporting Hanford contractors in matters regarding internal dosimetry. 13 refs., 16 figs., 42 tabs.

  15. Effect of syngeneic marrow injection upon recovery in sub- and near-lethally irradiated mice

    SciTech Connect

    Boggs, S.S.; Boggs, D.R.; Patrene, K.D.

    1989-06-01

    Mice were given sub-lethal (200-600 cGy) or near-lethal (800 cGy) whole body irradiation and the effect of injecting syngeneic marrow on subsequent hematopoietic recovery was studied. Marrow cell injection enhanced erythropoietic recovery after sub-lethal irradiation as reflected in hematocrit values and rate of appearance of /sup 59/Fe-labeled red cells in blood. However, this enhanced erythropoiesis was only seen in the spleen, and /sup 59/Fe uptake in marrow was reduced. When the irradiation dose was kept constant and the marrow dose increased from 10(5) to 10(6) to 10(7) cells, there was a somewhat erratic increase in spleen /sup 59/Fe and a decrease in marrow /sup 59/Fe uptake. When marrow cell number was kept constant and the dose of irradiation was increased from 200 to 400 to 600 to 800 cGy, there was an exponential increase in spleen /sup 59/Fe uptake but the marrow /sup 59/Fe uptake changed from depressed after lower doses to increased after 800 cGy. Cell injection after sub-lethal irradiation did not increase or decrease granulocytopoiesis. Injection of irradiated marrow cells also reduced marrow erythropoiesis and this was evident after both sub- and near-lethal irradiation. However, injection of irradiated cells did not increase splenic erythropoiesis. Following splenectomy, the depressed marrow erythropoiesis attending injection of viable cells was virtually eliminated but no increase was seen. These data suggest that the injection of autologous or syngeneic marrow may not be effective as a means of accelerating hematopoietic recovery after irradiation unless near-lethal or lethal dose have been received.

  16. Red blood cell decreases of microgravity

    NASA Technical Reports Server (NTRS)

    Johnson, P. C.

    1985-01-01

    Postflight decreases in red blood cell mass (RBCM) have regularly been recorded after exposure to microgravity. These 5-25 percent decreases do not relate to the mission duration, workload, caloric intake or to the type of spacecraft used. The decrease is accompanied by normal red cell survivals, increased ferritin levels, normal radioactive iron studies, and increases in mean red blood cell volume. Comparable decreases in red blood cell mass are not found after bed rest, a commonly used simulation of the microgravity state. Inhibited bone marrow erythropoiesis has not been proven to date, although reticulocyte numbers in the peripheral circulation are decreased about 50 percent. To date, the cause of the microgravity induced decreases in RBCM is unknown. Increased splenic trapping of circulating red blood cells seem the most logical way to explain the results obtained.

  17. Evaluation of the in vivo genotoxicity of Allura Red AC (Food Red No. 40).

    PubMed

    Honma, Masamitsu

    2015-10-01

    Allura Red AC (Food Red No. 40) is a red azo dye that is used for food coloring in beverage and confectionary products. However, its genotoxic properties remain controversial. To clarify the in vivo genotoxicity, we treated mice with Allura Red AC and investigated the induction of DNA damage (liver, glandular stomach), clastogenicity/anuegenicity (bone marrow), and mutagenicity (liver, glandular stomach) using Comet assays, micronucleus tests, and transgenic gene mutation assays, respectively. All studies were conducted in accordance with the Organization for Economic Co-operation and Development (OECD) guideline. Although Allura Red AC was administered up to the maximum doses recommended by the OECD guideline, no genotoxic effect was observed in any of the genotoxic endpoints. These data clearly show no evidence of in vivo genotoxic potential of Allura Red AC administered up to the maximum doses in mice. PMID:26364875

  18. Skeletal dosimetry for external exposures to photons based on {mu}CT images of spongiosa: Consideration of voxel resolution, cluster size, and medullary bone surfaces

    SciTech Connect

    Kramer, R.; Khoury, H. J.; Vieira, J. W.; Brown, K. A. Robson

    2009-11-15

    Skeletal dosimetry based on {mu}CT images of trabecular bone has recently been introduced to calculate the red bone marrow (RBM) and the bone surface cell (BSC) equivalent doses in human phantoms for external exposure to photons. In order to use the {mu}CT images for skeletal dosimetry, spongiosa voxels in the skeletons were replaced at run time by so-called micromatrices, which have exactly the size of a spongiosa voxel and contain segmented trabecular bone and marrow microvoxels. A cluster (=parallelepiped) of 2x2x2=8 micromatrices was used systematically and periodically throughout the spongiosa volume during the radiation transport calculation. Systematic means that when a particle leaves a spongiosa voxel to enter into a neighboring spongiosa voxel, then the next micromatrix in the cluster will be used. Periodical means that if the particle travels through more than two spongiosa voxels in a row, then the cluster will be repeated. Based on the bone samples available at the time, clusters of up to 3x3x3=27 micromatrices were studied. While for a given trabecular bone volume fraction the whole-body RBM equivalent dose showed converging results for cluster sizes between 8 and 27 micromatrices, this was not the case for the BSC equivalent dose. The BSC equivalent dose seemed to be very sensitive to the number, form, and thickness of the trabeculae. In addition, the cluster size and/or the microvoxel resolution were considered to be possible causes for the differences observed. In order to resolve this problem, this study used a bone sample large enough to extract clusters containing up to 8x8x8=512 micromatrices and which was scanned with two different voxel resolutions. Taking into account a recent proposal, this investigation also calculated the BSC equivalent dose on medullary surfaces of cortical bone in the arm and leg bones. The results showed (1) that different voxel resolutions have no effect on the RBM equivalent dose but do influence the BSC equivalent

  19. Red Sky with Red Mesa

    SciTech Connect

    2011-04-14

    The Red Sky/Red Mesa supercomputing platform dramatically reduces the time required to simulate complex fuel models, from 4-6 months to just 4 weeks, allowing researchers to accelerate the pace at which they can address these complex problems. Its speed also reduces the need for laboratory and field testing, allowing for energy reduction far beyond data center walls.

  20. Red Sky with Red Mesa

    ScienceCinema

    None

    2014-06-23

    The Red Sky/Red Mesa supercomputing platform dramatically reduces the time required to simulate complex fuel models, from 4-6 months to just 4 weeks, allowing researchers to accelerate the pace at which they can address these complex problems. Its speed also reduces the need for laboratory and field testing, allowing for energy reduction far beyond data center walls.

  1. Red Capes, Red Herrings, and Red Flags.

    ERIC Educational Resources Information Center

    Fiske, Donald W.

    The argument that the personality structures obtained from retrospective ratings reflect semantic similarity structures has been as provocative as a red cape in the bull ring. High congruence between those two kinds of structures seems well established. What is less clear is how and why those structures differ from that for immediate judgments of…

  2. Space radiation dosimetry

    SciTech Connect

    Hanser, F.A.; Dichter, B.K. ||

    1993-12-31

    Dosimetry is the measurement of the energy deposited in matter by various forms of radiation. In space the radiation is primarily energetic electrons, protons and heavier ions from planetary radiation belts, solar flares, and interstellar cosmic rays. Experimentally, dose is frequently obtained by summing the individual energy deposits in a solid state detector. If the detector is calibrated and the sensitive mass is known, the energy sum can be converted directly to accumulated radiation dose in Gy (J/kg). Such detectors can also be used to provide an approximate separation of dose into the components due to electrons, protons, and heavier ions, which is useful if it is desired to convert the measured dose into a biological effective dose (Sv) for manned spaceflight purposes. The output can also be used to provide an essentially instantaneous dose rate for use as warning devices. This is the primary type of space radiation dosimeter to be discussed here. The MOS-type dosimeter is another solid state sensor which can be of small size and low power. These devices integrate the total dose once through, can not separate particle types, and are not suitable for instantaneous dose rate measurement at low levels. There are several additional methods of measuring space radiation dose using scintillators, etc., but are not discussed in detail. In this paper emphasis is given to descriptions of active solid state detector instruments which have successfully worked in space. Some results of in-orbit dose measurements are presented.

  3. Red and NIR light dosimetry in the human deep brain

    NASA Astrophysics Data System (ADS)

    Pitzschke, A.; Lovisa, B.; Seydoux, O.; Zellweger, M.; Pfleiderer, M.; Tardy, Y.; Wagnières, G.

    2015-04-01

    Photobiomodulation (PBM) appears promising to treat the hallmarks of Parkinson’s Disease (PD) in cellular or animal models. We measured light propagation in different areas of PD-relevant deep brain tissue during transcranial, transsphenoidal illumination (at 671 and 808 nm) of a cadaver head and modeled optical parameters of human brain tissue using Monte-Carlo simulations. Gray matter, white matter, cerebrospinal fluid, ventricles, thalamus, pons, cerebellum and skull bone were processed into a mesh of the skull (158 × 201 × 211 voxels; voxel side length: 1 mm). Optical parameters were optimized from simulated and measured fluence rate distributions. The estimated μeff for the different tissues was in all cases larger at 671 than at 808 nm, making latter a better choice for light delivery in the deep brain. Absolute values were comparable to those found in the literature or slightly smaller. The effective attenuation in the ventricles was considerably larger than literature values. Optimization yields a new set of optical parameters better reproducing the experimental data. A combination of PBM via the sphenoid sinus and oral cavity could be beneficial. A 20-fold higher efficiency of light delivery to the deep brain was achieved with ventricular instead of transcranial illumination. Our study demonstrates that it is possible to illuminate deep brain tissues transcranially, transsphenoidally and via different application routes. This opens therapeutic options for sufferers of PD or other cerebral diseases necessitating light therapy.

  4. Nuclear accident dosimetry intercomparison studies.

    PubMed

    Sims, C S

    1989-09-01

    Twenty-two nuclear accident dosimetry intercomparison studies utilizing the fast-pulse Health Physics Research Reactor at the Oak Ridge National Laboratory have been conducted since 1965. These studies have provided a total of 62 different organizations a forum for discussion of criticality accident dosimetry, an opportunity to test their neutron and gamma-ray dosimetry systems under a variety of simulated criticality accident conditions, and the experience of comparing results with reference dose values as well as with the measured results obtained by others making measurements under identical conditions. Sixty-nine nuclear accidents (27 with unmoderated neutron energy spectra and 42 with eight different shielded spectra) have been simulated in the studies. Neutron doses were in the 0.2-8.5 Gy range and gamma doses in the 0.1-2.0 Gy range. A total of 2,289 dose measurements (1,311 neutron, 978 gamma) were made during the intercomparisons. The primary methods of neutron dosimetry were activation foils, thermoluminescent dosimeters, and blood sodium activation. The main methods of gamma dose measurement were thermoluminescent dosimeters, radiophotoluminescent glass, and film. About 68% of the neutron measurements met the accuracy guidelines (+/- 25%) and about 52% of the gamma measurements met the accuracy criterion (+/- 20%) for accident dosimetry. PMID:2777549

  5. Aspiration and Biopsy: Bone Marrow

    MedlinePlus

    ... A Recipes En Español Teachers - Looking for Health Lessons? Visit KidsHealth in the Classroom What Other Parents ... bone marrow sample for procedures (such as a stem cell transplant ) or other testing (such as chromosomal ...

  6. Initial radiation dosimetry at Hiroshima and Nagasaki

    SciTech Connect

    Loewe, W.E.

    1983-09-01

    The dosimetry of A-bomb survivors at Hiroshima and Nagasaki is discussed in light of the new dosimetry developed in 1980 by the author. The important changes resulting from the new dosimetry are the ratios of neutron to gamma doses, particularly at Hiroshima. The implications of these changes in terms of epidemiology and radiation protection standards are discussed. (ACR)

  7. 4.2 Methods for Internal Dosimetry

    NASA Astrophysics Data System (ADS)

    Noßke, D.; Mattsson, S.; Johansson, L.

    This document is part of Subvolume A 'Fundamentals and Data in Radiobiology, Radiation Biophysics, Dosimetry and Medical Radiological Protection' of Volume 7 'Medical Radiological Physics' of Landolt-Börnstein - Group VIII 'Advanced Materials and Technologies'. It contains the Section '4.2 Methods for Internal Dosimetry' of the Chapter '4 Dosimetry in Nuclear Medicine Diagnosis and Therapy' with the contents:

  8. Internal dose to active marrow and endosteum from radioactive iodine.

    PubMed

    Hoseinian-Azghadi, E; Rafat-Motavalli, L; Miri-Hakimabad, H

    2015-04-01

    This study analyses the active marrow and endosteum dose differences between the new International Commission on Radiological Protection (ICRP) male and female reference computational phantoms and the stylised phantom for two thyroid agents. The active marrow and endosteum doses from (131)I and (123)I were calculated for 0-55 % maximum thyroid uptakes using the MCNP-4C Monte Carlo code. The biokinetic models were taken from ICRP Publication 53. To evaluate the absorbed doses to red marrow and endosteum, the deposited energy was determined for the 19 spongiosa regions and 6 medullary cavities and was mass weighted using the mass fractions available in ICRP Publication 116. The results were then compared with the published values given in ICRP Publication 53. The poor anatomic realism of the stylised phantom used in ICRP Publication 53 leads to important dose differences between the ICRP voxel phantoms and the stylised phantom. The influence of the use of different bone material was also investigated. Underestimations of ∼60% were observed for active marrow doses of the stylised phantom compared with reference voxel phantoms. The results highlight the importance of the accuracy of the shape and inter-organ distances of the anthropomorphic model used. PMID:25157198

  9. Fourth Personnel Dosimetry Intercomparison Study

    SciTech Connect

    Dickson, H.W.

    1980-02-01

    The fourth Personnel Dosimetry Intercomparison Study was held at the Oak Ridge National Laboratory's Dosimetry Applications Research Facility during March 15-23, 1978. The Health Physics Research Reactor (HPRR) used unshielded, with a 12-cm-thick Lucite shield, a 20-cm-thick concrete shield, or a 5-cm-thick steel and 15-cm-thick concrete shield, and provided four neutron and gamma-ray spectra. Then the dose was calculated based on the HPRR neutron spectra and dose conversion factors which had been determined previously for the four spectra. The results of these personnel dosimetry intercomparison studies reveal that estimates of dose equivalent vary over a wide range. The standard deviation of the mean of participants data for gamma measurements was in the range of 29 to 43%; for neutrons it was 57 to 188%. (PCS)

  10. TVA's dosimetry technician training program

    SciTech Connect

    Hudson, C.G.; Faust, V.L.; Cornelius, T.W.; Regan, J.M.; Farrell, W.E. )

    1984-04-01

    In 1984, the Tennessee Valley Authority decentralized its personnel TLD program and established TLD processing facilities at each of its nuclear plant sites. This article describes the training program that was developed to aid in staffing dosimetry technician positions at each of the plants. The scope of the dosimetry technician's duties include TLD processing, operation of a computerized records system, whole-body counting system operation, and respirator mask fit-testing. The training program includes thirteen weeks of classroom and laboratory training plus a 15-month apprenticeship at a nuclear plant. Retraining and requalification are performed on an annual basis.

  11. Monte Carlo portal dosimetry

    SciTech Connect

    Chin, P.W. . E-mail: mary.chin@physics.org

    2005-10-15

    This project developed a solution for verifying external photon beam radiotherapy. The solution is based on a calibration chain for deriving portal dose maps from acquired portal images, and a calculation framework for predicting portal dose maps. Quantitative comparison between acquired and predicted portal dose maps accomplishes both geometric (patient positioning with respect to the beam) and dosimetric (two-dimensional fluence distribution of the beam) verifications. A disagreement would indicate that beam delivery had not been according to plan. The solution addresses the clinical need for verifying radiotherapy both pretreatment (without the patient in the beam) and on treatment (with the patient in the beam). Medical linear accelerators mounted with electronic portal imaging devices (EPIDs) were used to acquire portal images. Two types of EPIDs were investigated: the amorphous silicon (a-Si) and the scanning liquid ion chamber (SLIC). The EGSnrc family of Monte Carlo codes were used to predict portal dose maps by computer simulation of radiation transport in the beam-phantom-EPID configuration. Monte Carlo simulations have been implemented on several levels of high throughput computing (HTC), including the grid, to reduce computation time. The solution has been tested across the entire clinical range of gantry angle, beam size (5 cmx5 cm to 20 cmx20 cm), and beam-patient and patient-EPID separations (4 to 38 cm). In these tests of known beam-phantom-EPID configurations, agreement between acquired and predicted portal dose profiles was consistently within 2% of the central axis value. This Monte Carlo portal dosimetry solution therefore achieved combined versatility, accuracy, and speed not readily achievable by other techniques.

  12. Characteristics of marrow production and reticulocyte maturation in normal man in response to anemia

    PubMed Central

    Hillman, Robert S.

    1969-01-01

    Erythropoiesis in normal man was studied during periods of phlebotomy-induced anemia of varying severity. This study permitted a comparison of marrow production measurements over a wide range of marrow production levels. As long as the serum iron remained above 50 μg/100 ml, measurements of plasma iron turnover provided an excellent index of marrow production at all levels of red cell production. In contrast, the absolute reticulocyte count demonstrated a poor correlation with the other measurements. This was shown to be the result of a prolongation of the time required for circulating reticulocytes to lose their reticulum, which correlated with the severity of the anemia. For the clinical application of the reticulocyte count as a measurement of marrow production, an adjustment must be made for this alteration in the circulating reticulocyte maturation time. PMID:5773082

  13. What Happens During a Bone Marrow Transplant? | NIH MedlinePlus the Magazine

    MedlinePlus

    ... procedure allows the recipient to get new stem cells that work properly. Stem cells are found in bone marrow, ... The body doesn’t make enough red blood cells, or they don’t work properly. Certain immune-deficiency diseases that prevent the ...

  14. An image-based skeletal dosimetry model for the ICRP reference newborn—internal electron sources

    NASA Astrophysics Data System (ADS)

    Pafundi, Deanna; Rajon, Didier; Jokisch, Derek; Lee, Choonsik; Bolch, Wesley

    2010-04-01

    In this study, a comprehensive electron dosimetry model of newborn skeletal tissues is presented. The model is constructed using the University of Florida newborn hybrid phantom of Lee et al (2007 Phys. Med. Biol. 52 3309-33), the newborn skeletal tissue model of Pafundi et al (2009 Phys. Med. Biol. 54 4497-531) and the EGSnrc-based Paired Image Radiation Transport code of Shah et al (2005 J. Nucl. Med. 46 344-53). Target tissues include the active bone marrow (surrogate tissue for hematopoietic stem cells), shallow marrow (surrogate tissue for osteoprogenitor cells) and unossified cartilage (surrogate tissue for chondrocytes). Monoenergetic electron emissions are considered over the energy range 1 keV to 10 MeV for the following source tissues: active marrow, trabecular bone (surfaces and volumes), cortical bone (surfaces and volumes) and cartilage. Transport results are reported as specific absorbed fractions according to the MIRD schema and are given as skeletal-averaged values in the paper with bone-specific values reported in both tabular and graphic format as electronic annexes (supplementary data). The method utilized in this work uniquely includes (1) explicit accounting for the finite size and shape of newborn ossification centers (spongiosa regions), (2) explicit accounting for active and shallow marrow dose from electron emissions in cortical bone as well as sites of unossified cartilage, (3) proper accounting of the distribution of trabecular and cortical volumes and surfaces in the newborn skeleton when considering mineral bone sources and (4) explicit consideration of the marrow cellularity changes for active marrow self-irradiation as applicable to radionuclide therapy of diseased marrow in the newborn child.

  15. A stochastic model of radiation-induced bone marrow damage

    SciTech Connect

    Cotlet, G.; Blue, T.E.

    2000-03-01

    A stochastic model, based on consensus principles from radiation biology, is used to estimate bone-marrow stem cell pool survival (CFU-S and stroma cells) after irradiation. The dose response model consists of three coupled first order linear differential equations which quantitatively describe time dependent cellular damage, repair, and killing of red bone marrow cells. This system of differential equations is solved analytically through the use of a matrix approach for continuous and fractionated irradiations. The analytic solutions are confirmed through the dynamical solution of the model equations using SIMULINK. Rate coefficients describing the cellular processes of radiation damage and repair, extrapolated to humans from animal data sets and adjusted for neutron-gamma mixed fields, are employed in a SIMULINK analysis of criticality accidents. The results show that, for the time structures which may occur in criticality accidents, cell survival is established mainly by the average dose and dose rate.

  16. Modeling Hematopoiesis and Responses to Radiation Countermeasures in a Bone Marrow-on-a-Chip.

    PubMed

    Torisawa, Yu-Suke; Mammoto, Tadanori; Jiang, Elisabeth; Jiang, Amanda; Mammoto, Akiko; Watters, Alexander L; Bahinski, Anthony; Ingber, Donald E

    2016-05-01

    Studies on hematopoiesis currently rely on animal models because in vitro culture methods do not accurately recapitulate complex bone marrow physiology. We recently described a bone marrow-on-a-chip microfluidic device that enables the culture of living hematopoietic bone marrow and mimics radiation toxicity in vitro. In the present study, we used this microdevice to demonstrate continuous blood cell production in vitro and model bone marrow responses to potential radiation countermeasure drugs. The device maintained mouse hematopoietic stem and progenitor cells in normal proportions for at least 2 weeks in culture. Increases in the number of leukocytes and red blood cells into the microfluidic circulation also could be detected over time, and addition of erythropoietin induced a significant increase in erythrocyte production. Exposure of the bone marrow chip to gamma radiation resulted in reduction of leukocyte production, and treatment of the chips with two potential therapeutics, granulocyte-colony stimulating factor or bactericidal/permeability-increasing protein (BPI), induced significant increases in the number of hematopoietic stem cells and myeloid cells in the fluidic outflow. In contrast, BPI was not found to have any effect when analyzed using static marrow cultures, even though it has been previously shown to accelerate recovery from radiation-induced toxicity in vivo. These findings demonstrate the potential value of the bone marrow-on-a-chip for modeling blood cell production, monitoring responses to hematopoiesis-modulating drugs, and testing radiation countermeasures in vitro. PMID:26993746

  17. A probabilistic gastrointestinal tract dosimetry model

    NASA Astrophysics Data System (ADS)

    Huh, Chulhaeng

    In internal dosimetry, the tissues of the gastrointestinal (GI) tract represent one of the most radiosensitive organs of the body with the hematopoietic bone marrow. Endoscopic ultrasound is a unique tool to acquire in-vivo data on GI tract wall thicknesses of sufficient resolution needed in radiation dosimetry studies. Through their different echo texture and intensity, five layers of differing echo patterns for superficial mucosa, deep mucosa, submucosa, muscularis propria and serosa exist within the walls of organs composing the alimentary tract. Thicknesses for stomach mucosa ranged from 620 +/- 150 mum to 1320 +/- 80 mum (total stomach wall thicknesses from 2.56 +/- 0.12 to 4.12 +/- 0.11 mm). Measurements made for the rectal images revealed rectal mucosal thicknesses from 150 +/- 90 mum to 670 +/- 110 mum (total rectal wall thicknesses from 2.01 +/- 0.06 to 3.35 +/- 0.46 mm). The mucosa thus accounted for 28 +/- 3% and 16 +/- 6% of the total thickness of the stomach and rectal wall, respectively. Radiation transport simulations were then performed using the Monte Carlo N-particle transport code (MCNP) 4C transport code to calculate S values (Gy/Bq-s) for penetrating and nonpenetrating radiations such as photons, beta particles, conversion electrons and auger electrons of selected nuclides, I123, I131, Tc 99m and Y90 under two source conditions: content and mucosa sources, respectively. The results of this study demonstrate generally good agreement with published data for the stomach mucosa wall. The rectal mucosa data are consistently higher than published data compared with the large intestine due to different radiosensitive cell thicknesses (350 mum vs. a range spanning from 149 mum to 729 mum) and different geometry when a rectal content source is considered. Generally, the ICRP models have been designed to predict the amount of radiation dose in the human body from a "typical" or "reference" individual in a given population. The study has been performed to

  18. Mechanics of intact bone marrow.

    PubMed

    Jansen, Lauren E; Birch, Nathan P; Schiffman, Jessica D; Crosby, Alfred J; Peyton, Shelly R

    2015-10-01

    The current knowledge of bone marrow mechanics is limited to its viscous properties, neglecting the elastic contribution of the extracellular matrix. To get a more complete view of the mechanics of marrow, we characterized intact yellow porcine bone marrow using three different, but complementary techniques: rheology, indentation, and cavitation. Our analysis shows that bone marrow is elastic, and has a large amount of intra- and inter-sample heterogeneity, with an effective Young׳s modulus ranging from 0.25 to 24.7 kPa at physiological temperature. Each testing method was consistent across matched tissue samples, and each provided unique benefits depending on user needs. We recommend bulk rheology to capture the effects of temperature on tissue elasticity and moduli, indentation for quantifying local tissue heterogeneity, and cavitation rheology for mitigating destructive sample preparation. We anticipate the knowledge of bone marrow elastic properties for building in vitro models will elucidate mechanisms involved in disease progression and regenerative medicine. PMID:26189198

  19. Cobalt-60 total body irradiation dosimetry at 220 cm source-axis distance

    SciTech Connect

    Glasgow, G.P.; Mill, W.B.

    1980-06-01

    Adults with acute leukemia are treated with cyclophosphamide and total body irradiation (TBI) followed by autologous marrow transplants. For TBI, patients seated in a stand angled 45/sup 0/ above the floor are treated for about 2 hours at 220 cm source-axis distance (SAD) with sequential right and left lateral 87 cm x 87 cm fields to a 900 rad mid-pelvic dose at about 8 rad/min using a 5000 Ci cobalt unit. Maximum (lateral) to minimum (mid-plane) dose ratios are: hips--1.15, shoulders--1.30, and head--1.05, which is shielded by a compensator filter. Organ doses are small intestine, liver and kidneys--1100 rad, lung--1100 to 1200 rad, and heart--1300 rad. Verification dosimetry reveals the prescribed dose is delivered to within +-5%. Details of the dosimetry of this treatment are presented.

  20. Neocytolysis: physiological down-regulator of red-cell mass

    NASA Technical Reports Server (NTRS)

    Alfrey, C. P.; Rice, L.; Udden, M. M.; Driscoll, T. B.

    1997-01-01

    It is usually considered that red-cell mass is controlled by erythropoietin-driven bone marrow red-cell production, and no physiological mechanisms can shorten survival of circulating red cells. In adapting to acute plethora in microgravity, astronauts' red-cell mass falls too rapidly to be explained by diminished red-cell production. Ferrokinetics show no early decline in erythropolesis, but red cells radiolabelled 12 days before launch survive normally. Selective destruction of the youngest circulating red cells-a process we call neocytolysis-is the only plausible explanation. A fall in erythropoietin below a threshold is likely to initiate neocytolysis, probably by influencing surface-adhesion molecules. Recognition of neocytolysis will require re-examination of the pathophysiology and treatment of several blood disorders, including the anaemia of renal disease.

  1. Bone marrow and splenic histology in hairy cell leukaemia.

    PubMed

    Wotherspoon, Andrew; Attygalle, Ayoma; Mendes, Larissa Sena Teixeira

    2015-12-01

    Hairy cell leukaemia is a rare chronic neoplastic B-cell lymphoproliferation that characteristically involves blood, bone marrow and spleen with liver, lymph node and skin less commonly involved. Histologically, the cells have a characteristic appearance with pale/clear cytoplasm and round or reniform nuclei. In the spleen, the infiltrate involves the red pulp and is frequently associated with areas of haemorrhage (blood lakes). The cells stain for B-cell related antigens as well as with antibodies against tartrate-resistant acid phosphatase, DBA44 (CD72), CD11c, CD25, CD103, CD123, cyclin D1 and annexin A1. Mutation of BRAF -V600E is present and antibody to the mutant protein can be used as a specific marker. Bone marrow biopsy is essential in the initial assessment of disease as the bone marrow may be inaspirable or unrepresentative of degree of marrow infiltration as a result of the tumour associated fibrosis preventing aspiration of the tumour cell component. Bone marrow biopsy is important in the assessment of therapy response but in this context staining for CD11c and Annexin A1 is not helpful as they are also markers of myeloid lineage and identification of low level infiltration may be obscured. In this context staining for CD20 may be used in conjunction with morphological assessment and staining of serial sections for cyclin D1 and DBA44 to identify subtle residual infiltration. Staining for CD79a and CD19 is not recommended as these antibodies will identify plasma cells and can lead to over-estimation of disease. Staining for CD20 should not be used in patients following with anti-CD20 based treatments. Down regulation of cyclin D1 and CD25 has been reported in patients following BRAF inhibitor therapy and assessment of these antigens should not be used in this context. Histologically, hairy cell leukaemia needs to be distinguished from other B-cell lymphoproliferations associated with splenomegaly including splenic marginal zone lymphoma, splenic

  2. [Inherited bone marrow failure syndromes].

    PubMed

    Okuno, Yusuke

    2016-02-01

    Inherited bone marrow failure syndromes comprise a series of disorders caused by various gene mutations. Genetic tests were formerly difficult to perform because of the large size and number of causative genes. However, recent advances in next-generation sequencing has enabled simultaneous testing of all causative genes to be performed at an acceptable cost. We collaboratively conducted a series of whole-exome sequencing studies of patients with inherited bone marrow failure syndromes and discovered RPS27/RPL27 and FANCT as causative genes of Diamond-Blackfan anemia and Fanconi anemia, respectively. Furthermore, we established a target gene sequencing system to cover 189 genes associated with pediatric blood diseases to assist genetic diagnoses in clinical practice. In this review, discovery of new causative genes and possible roles of next-generation sequencing in the genetic diagnosis of inherited bone marrow failure syndromes are discussed. PMID:26935625

  3. How flatbed scanners upset accurate film dosimetry.

    PubMed

    van Battum, L J; Huizenga, H; Verdaasdonk, R M; Heukelom, S

    2016-01-21

    Film is an excellent dosimeter for verification of dose distributions due to its high spatial resolution. Irradiated film can be digitized with low-cost, transmission, flatbed scanners. However, a disadvantage is their lateral scan effect (LSE): a scanner readout change over its lateral scan axis. Although anisotropic light scattering was presented as the origin of the LSE, this paper presents an alternative cause. Hereto, LSE for two flatbed scanners (Epson 1680 Expression Pro and Epson 10000XL), and Gafchromic film (EBT, EBT2, EBT3) was investigated, focused on three effects: cross talk, optical path length and polarization. Cross talk was examined using triangular sheets of various optical densities. The optical path length effect was studied using absorptive and reflective neutral density filters with well-defined optical characteristics (OD range 0.2-2.0). Linear polarizer sheets were used to investigate light polarization on the CCD signal in absence and presence of (un)irradiated Gafchromic film. Film dose values ranged between 0.2 to 9 Gy, i.e. an optical density range between 0.25 to 1.1. Measurements were performed in the scanner's transmission mode, with red-green-blue channels. LSE was found to depend on scanner construction and film type. Its magnitude depends on dose: for 9 Gy increasing up to 14% at maximum lateral position. Cross talk was only significant in high contrast regions, up to 2% for very small fields. The optical path length effect introduced by film on the scanner causes 3% for pixels in the extreme lateral position. Light polarization due to film and the scanner's optical mirror system is the main contributor, different in magnitude for the red, green and blue channel. We concluded that any Gafchromic EBT type film scanned with a flatbed scanner will face these optical effects. Accurate dosimetry requires correction of LSE, therefore, determination of the LSE per color channel and dose delivered to the film. PMID:26689962

  4. How flatbed scanners upset accurate film dosimetry

    NASA Astrophysics Data System (ADS)

    van Battum, L. J.; Huizenga, H.; Verdaasdonk, R. M.; Heukelom, S.

    2016-01-01

    Film is an excellent dosimeter for verification of dose distributions due to its high spatial resolution. Irradiated film can be digitized with low-cost, transmission, flatbed scanners. However, a disadvantage is their lateral scan effect (LSE): a scanner readout change over its lateral scan axis. Although anisotropic light scattering was presented as the origin of the LSE, this paper presents an alternative cause. Hereto, LSE for two flatbed scanners (Epson 1680 Expression Pro and Epson 10000XL), and Gafchromic film (EBT, EBT2, EBT3) was investigated, focused on three effects: cross talk, optical path length and polarization. Cross talk was examined using triangular sheets of various optical densities. The optical path length effect was studied using absorptive and reflective neutral density filters with well-defined optical characteristics (OD range 0.2-2.0). Linear polarizer sheets were used to investigate light polarization on the CCD signal in absence and presence of (un)irradiated Gafchromic film. Film dose values ranged between 0.2 to 9 Gy, i.e. an optical density range between 0.25 to 1.1. Measurements were performed in the scanner’s transmission mode, with red-green-blue channels. LSE was found to depend on scanner construction and film type. Its magnitude depends on dose: for 9 Gy increasing up to 14% at maximum lateral position. Cross talk was only significant in high contrast regions, up to 2% for very small fields. The optical path length effect introduced by film on the scanner causes 3% for pixels in the extreme lateral position. Light polarization due to film and the scanner’s optical mirror system is the main contributor, different in magnitude for the red, green and blue channel. We concluded that any Gafchromic EBT type film scanned with a flatbed scanner will face these optical effects. Accurate dosimetry requires correction of LSE, therefore, determination of the LSE per color channel and dose delivered to the film.

  5. Widespread marrow necrosis during pregnancy

    SciTech Connect

    Knickerbocker, W.J.; Quenville, N.F.

    1982-11-01

    Recently, a 22-year-old Caucasian female was referred to our Hospital two days post-partum. She had been feeling unwell during the last few days of her pregnancy and complained of multiple aches and pains, worst in the abdomen and lower back. Her admission platelet count was severely depressed and a bone biopsy showed extensive marrow necrosis with viable bony trabeculae. There was no evidence of vasculitis, vascular thrombosis, or malignancy. Widespread marrow necrosis in pregnancy followed by recovery, to our knowledge, has not been previously reported.

  6. Bone Marrow Transplants: "Another Possibility at Life"

    MedlinePlus

    ... of this page please turn Javascript on. Feature: Bone Marrow Transplants “Another Possibility at Life” Past Issues / Summer ... year, and, for 16,000 of them, a bone marrow transplant is the best treatment option, notes Susan ...

  7. Planning for a Bone Marrow Transplant (BMT)

    MedlinePlus

    ... us Digg Facebook Google Bookmarks Planning for a Bone Marrow Transplant (BMT) If you're going to have ... to a friend or family member undergoing a bone marrow or cord blood transplant. Help Your Loved One ...

  8. Transplant Outcomes (Bone Marrow and Cord Blood)

    MedlinePlus

    ... reports show patient survival and transplant data of bone marrow and umbilical cord blood transplants in the transplant ... Data by Center Report —View the number of bone marrow and cord blood transplants performed at a specific ...

  9. Marrow Fat and Bone—New Perspectives

    PubMed Central

    Fazeli, Pouneh K.; Horowitz, Mark C.; MacDougald, Ormond A.; Scheller, Erica L.; Rodeheffer, Matthew S.; Rosen, Clifford J.

    2013-01-01

    Context: There is growing interest in the relationship between bone mineral density, bone strength, and fat depots. Marrow adipose tissue, a well-established component of the marrow environment, is metabolically distinct from peripheral fat depots, but its functional significance is unknown. Objective: In this review, we discuss animal and human data linking the marrow adipose tissue depot to parameters of bone density and integrity as well as the potential significance of marrow adipose tissue in metabolic diseases associated with bone loss, including type 1 diabetes mellitus and anorexia nervosa. Potential hormonal determinants of marrow adipose tissue are also discussed. Conclusions: We conclude that whereas most animal and human data demonstrate an inverse association between marrow adipose tissue and measures of bone density and strength, understanding the functional significance of marrow adipose tissue and its hormonal determinants will be critical to better understanding its role in skeletal integrity and the role of marrow adipose tissue in the pathophysiology of bone loss. PMID:23393168

  10. Unexplained overexposures on physical dosimetry reported by biological dosimetry.

    PubMed

    Montoro, A; Almonacid, M; Villaescusa, J I; Verdu, G

    2009-01-01

    The Medical Service of the Radiation Protection Service from the University Hospital La Fe (Valencia, Spain), carries out medical examinations of the workers occupationally exposed to ionising radiation. The Biological Dosimetry Laboratory is developing its activity since 2001. Up to now, the activities have been focused in performing biological dosimetry studies of Interventionists workers from La Fe Hospital. Recently, the Laboratory has been authorized by the Health Authority in the Valencian Community. Unexplained overexposures of workers and patients are also studied. Workers suspected of being overexposed to ionising radiation were referred for investigation by cytogenetic analysis. Two of these were from Hospitals of the Valencian Community and one belonged to an uranium mine from Portugal. Hospital workers had a physical dose by thermoluminiscence dosimeters (TLD) that exceeded the established limit. The worker of the uranium mine received a dose from a lost source of Cesium 137 with an activity of 170 mCi. All three cases showed normal values after the hematological analysis. Finally, the aim of this study consist to determine whether the dose showed by the dosimeter is reliable or not. In the case of workers that wore dosimeter, it is concluded that the doses measured by dosimeter are not corresponding to real doses. Hospital worker with a physical dose of 2.6 Sv and 0.269 Sv had an estimated absorbed dose by biological dosimetry of 0.076 Gy (0-0.165 Gy) and 0 Gy (0-0.089 Gy), respectively. In case of the mine worker an estimated absorbed dose of 0.073 Gy (0-0.159 Gy) was obtained by biological dosimetry. In all cases we used the odds ratio to present the results due to a very low frequency of observed aberrations [1]. PMID:19964943

  11. Results from 2010 Caliban Criticality Dosimetry Intercomparison

    SciTech Connect

    Veinot, K. G.

    2011-10-12

    The external dosimetry program participated in a criticality dosimetry intercomparison conducted at the Caliban facility in Valduc, France in 2010. Representatives from the dosimetry and instrumentation groups were present during testing which included irradiations of whole-body beta/gamma (HBGT) and neutron thermoluminescent dosimeters (TLDs), a fixed nuclear accident dosimeter (FNAD), electronic alarming dosimeters, and a humanoid phantom filled with reference man concentrations of sodium. This report reviews the testing procedures, preparations, irradiations, and presents results of the tests.

  12. Fifth personnel dosimetry intercomparison study

    SciTech Connect

    Sims, C.S.

    1980-02-01

    The fifth Personnel Dosimetry Intercomparison Study (PDIS) was conducted at the Oak Ridge National Laboratory's (ORNL) Dosimetry Applications Research (DOSAR) facility on March 20-22, 1979. This study is the latest PDIS in the continuing series started at the DOSAR facility in 1974. The PDIS is a three day study, typically in March, where personnel dosimeters are mailed to the DOSAR facility, exposed to a range of low-level neutron radiation doses (1 to 15 mSv or equivalently, 100 to 1500 mrem) and neutron-to-gamma ratios (1:1-10:1) using the Health Physics Research Reactor (HPRR) as the radiation source, and returned to the participants for evaluation. This report is a summary and analysis of the results reported by the various participants. The participants are able to intercompare their results with those of others who made dose measurements under identical experimental conditions.

  13. Neutron personnel dosimetry intecomparison studies

    SciTech Connect

    Sims, C.S.

    1991-01-01

    The Dosimetry Applications Research (DOSAR) Group at the Oak Ridge National Laboratory (ORNL) has conducted sixteen Neutron Personnel Dosimetry Intercomparison Studies (PDIS) since 1974. During these studies dosimeters are mailed to DOSAR, exposed to low-level (typically in the 0.3 -- 5.0 mSv range) neutron dose equivalents in a variety of mixed neutron-gamma radiation fields, and then returned to the participants for evaluation. The Health Physics Research Reactor (HPRR) was used as the primary radiation source in PDIS 1--12 and radioisotopic neutron sources at DOSAR's Radiation Calibration Laboratory (RADCAL) were mainly used, along with sources and accelerators at cooperating institutions, in PDIS 13--16. Conclusions based on 13,560 measurements made by 146 different participating organizations (102 - US) are presented.

  14. Interspecies dosimetry of reactive gases

    SciTech Connect

    Miller, F.J.; Overton, J.H.; Gerrity, T.R.; Graham, R.C.

    1987-03-01

    The development of dosimetry models that can provide a description of the uptake and distribution of inhaled compounds throughout the body and the availability of animal toxicological data are integral components for a full evaluation of potential risks associated with human exposure. Interspecies dosimetric comparisons must be approached using a model conceptualization that incorporates the major factors affecting the uptake of the gas, such as respiratory tract morphology, route of breathing, depth and rate of breathing, physicochemical properties of the gas, etc. Modeling efforts thus far have primarily focused on ozone. A comparison of theoretical predictions of delivered dose of ozone to the lower respiratory tract of man shows good agreement with dose estimates derived from experimental measurements. Applications to ozone toxicological data in animals and man have been examined that incorporate the use of dosimetry models in studying quantitative dose-response relationships.

  15. Dosimetry study of [I-131] and [I-125]- meta-iodobenz guanidine in a simulating model for neuroblastoma metastasis.

    PubMed

    Roa, W H; Yaremko, B; McEwan, A; Amanie, J; Yee, D; Cho, J; McQuarrie, S; Riauka, T; Sloboda, R; Wiebe, L; Loebenberg, R; Janicki, C

    2013-02-01

    The physical properties of I-131 may be suboptimal for the delivery of therapeutic radiation to bone marrow metastases, which are common in the natural history of neuroblastoma. In vitro and preliminary clinical studies have implied improved efficacy of I-125 relative to I-131 in certain clinical situations, although areas of uncertainty remain regarding intratumoral dosimetry. This prompted our study using human neuroblastoma multicellular spheroids as a model of metastasis. 3D dose calculations were made using voxel-based Medical Internal Radiation Dosimetry (MIRD) and dose-point-kernel (DPK) techniques. Dose distributions for I-131 and I-125 labeled mIBG were calculated for spheroids (metastases) of various sizes from 0.01 cm to 3 cm diameter, and the relative dose delivered to the tumors was compared for the same limiting dose to the bone marrow. Based on the same data, arguments were advanced based upon the principles of tumor control probability (TCP) to emphasize the potential theoretical utility of I-125 over I-131 in specific clinical situations. I-125-mIBG can deliver a higher and more uniform dose to tumors compared to I-131 mIBG without increasing the dose to the bone marrow. Depending on the tumor size and biological half-life, the relative dose to tumors of less than 1 mm diameter can increase several-fold. TCP calculations indicate that tumor control increases with increasing administered activity, and that I-125 is more effective than I-131 for tumor diameters of 0.01 cm or less. This study suggests that I-125-mIBG is dosimetrically superior to I-131-mIBG therapy for small bone marrow metastases from neuroblastoma. It is logical to consider adding I-125-mIBG to I-131-mIBG in multi-modality therapy as these two isotopes could be complementary in terms of their cumulative dosimetry. PMID:22974332

  16. Gafchromic EBT2 film dosimetry in reflection mode with a novel plan-based calibration method

    SciTech Connect

    Mendez, I.; Hartman, V.; Hudej, R.; Strojnik, A.; Casar, B.

    2013-01-15

    Purpose:A dosimetric system formed by Gafchromic EBT2 radiochromic film and Epson Expression 10000XL flatbed scanner was commissioned for dosimetry. In this paper, several open questions concerning the commissioning of radiochromic films for dosimetry were addressed: (a) is it possible to employ this dosimetric system in reflection mode; (b) if so, can the methods used in transmission mode also be used in reflection mode; (c) is it possible to obtain accurate absolute dose measurements with Gafchromic EBT2 films; (d) which calibration method should be followed; (e) which calibration models should be used; and (f) does three-color channel dosimetry offer a significant improvement over single channel dosimetry. The purpose of this paper is to help clarify these questions. Methods: In this study, films were scanned in reflection mode, the effect of surrounding film was evaluated and the feasibility of EBT2 film dosimetry in reflection mode was studied. EBT2's response homogeneity has been reported to lead to excessive dose uncertainties. To overcome this problem, a new plan-based calibration method was implemented. Plan-based calibration can use every pixel and each of the three color channels of the scanned film to obtain the parameters of the calibration model. A model selection analysis was conducted to select lateral correction and sensitometric curve models. The commonly used calibration with fragments was compared with red-channel plan-based calibration and with three-channel plan-based calibration. Results: No effect of surrounding film was found in this study. The film response inhomogeneity in EBT2 films was found to be important not only due to differences in the fog but also due to differences in sensitivity. The best results for lateral corrections were obtained using absolute corrections independent of the dose. With respect to the sensitometric curves, an empirical polynomial fit of order 4 was found to obtain results equivalent to a gamma

  17. [The role of blood banks in bone marrow transplantation].

    PubMed

    Höcker, P; Wagner, A; Sklenar, G

    1991-01-01

    The transfusion service (TS) plays an important role in bone marrow transplantation (BMT). Many of the techniques and methods employed are also used in the daily work of a TS like tissue typing, apheresis techniques, handling of blood and its components under sterile conditions. In the pretransplantation phase the TS is responsible for the typing of recipient and presumptive donors, harvesting of autologous blood and selection of appropriate blood components. During BMT the TS can perform bone marrow harvesting, depletion of red cells in case of ABO-incompatibility and bone marrow manipulation when T-cell depletion or purging procedures are considered. Peripheral stem cell harvest by apheresis is also best performed by the TS experienced in such techniques. Storage of hematopoietic cells in liquid nitrogen and thawing are also techniques already used in most of the transfusion services. Post BMT, the support with blood components, irradiated and almost free of white cells to avoid TA-GVH and CMV-infection, is a major job of the TS. These facts demonstrate that a well organized transfusion service is a 'conditio sine qua non' for successful BMT. PMID:1725636

  18. Immune transfer studies in canine allogeneic marrow graft donor-recipient pairs

    SciTech Connect

    Grosse-Wilde, H.; Krumbacher, K.; Schuening, F.D.; Doxiadis, I.; Mahmoud, H.K.; Emde, C.; Schmidt-Weinmar, A.; Schaefer, U.W.

    1986-07-01

    Transfer of immunity occurring with bone marrow grafting was studied using the dog as a preclinical model. Allogeneic bone marrow transplantation (BMT) was performed between DLA-identical beagle litter-mates. The donors were immunized with tetanus toxoid (TT) or sheep red blood cells (SRBC), and their humoral response was monitored by hemagglutination. The recipients of bone marrow from TT-immunized donors showed a marked increase of antibody titer one week posttransplantation, while in the recipients of marrow from SRBC immunized donors the antibody titers were considerably lower. Within the following 60 days the antibody titers in both groups diminished gradually to pregrafting levels. Control experiments in which cell-free plasma from donors immunized with TT and SRBC respectively was transfused indicated that the initial rise of specific antibody titers after marrow grafting is likely to be due to a passive transfer of humoral immunity. A single challenge of these marrow graft recipients with the respective antigen 15-18 weeks posttransplantation led to a secondary type of humoral immune response. It could be demonstrated that transfer of memory against TT or SRBC was independent from the actual antibody titer and the time of vaccination of the donor. One dog was immunized with TT after serving as marrow donor. When the donor had shown an antibody response, a peripheral blood leukocytes (PBL) transfusion was given to his chimera. Subsequent challenge of the latter resulted in a secondary type of specific antibody response. This indicates that specific cellular-bound immunological memory can be transferred after BMT from the donor to his allogeneic bone marrow chimera by transfusion of peripheral blood leukocytes. The data may be of importance in clinical BMT to protect patients during the phase of reduced immune reactivity by transfer of memory cells.

  19. Primary bone marrow oedema syndromes.

    PubMed

    Patel, Sanjeev

    2014-05-01

    MRI scanning in patients with rheumatological conditions often shows bone marrow oedema, which can be secondary to inflammatory, degenerative, infective or malignant conditions but can also be primary. The latter condition is of uncertain aetiology and it is also uncertain whether it represents a stage in the progression to osteonecrosis in some patients. Patients with primary bone marrow oedema usually have lower limb pain, commonly the hip, knee, ankle or feet. The diagnosis is one of exclusion with the presence of typical MRI findings. Treatment is usually conservative and includes analgesics and staying off the affected limb. The natural history is that of gradual resolution of symptoms over a number of months. Evidence for medical treatment is limited, but open-label studies suggest bisphosphonates may help in the resolution of pain and improve radiological findings. Surgical decompression is usually used as a last resort. PMID:24080251

  20. Gillick, bone marrow and teenagers.

    PubMed

    Cherkassky, Lisa

    2015-09-01

    The Human Tissue Authority can authorise a bone marrow harvest on a child of any age if a person with parental responsibility consents to the procedure. Older children have the legal capacity to consent to medical procedures under Gillick, but it is unclear if Gillick can be applied to non-therapeutic medical procedures. The relevant donation guidelines state that the High Court shall be consulted in the event of a disagreement, but what is in the best interests of the teenage donor under s.1 of the Children Act 1989? There are no legal authorities on child bone marrow harvests in the United Kingdom. This article considers the best interests of the older saviour sibling and questions whether, for the purposes of welfare, the speculative benefits could outweigh the physical burdens. PMID:25911618

  1. 10 CFR 35.630 - Dosimetry equipment.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 1 2012-01-01 2012-01-01 false Dosimetry equipment. 35.630 Section 35.630 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Photon Emitting Remote Afterloader Units, Teletherapy Units, and Gamma Stereotactic Radiosurgery Units § 35.630 Dosimetry equipment. (a) Except for low dose-rate remote afterloader sources...

  2. Dosimetry in Nuclear Medicine Diagnosis and Therapy

    NASA Astrophysics Data System (ADS)

    Noßke, D.; Mattsson, S.; Johansson, L.

    This document is part of Subvolume A 'Fundamentals and Data in Radiobiology, Radiation Biophysics, Dosimetry and Medical Radiological Protection' of Volume 7 'Medical Radiological Physics' of Landolt-Börnstein - Group VIII 'Advanced Materials and Technologies'. It contains the Section '4.7 Necessity of Patient-Specific Dose Planning in Radionuclide Therapy' of the Chapter '4 Dosimetry in Nuclear Medicine Diagnosis and Therapy'.

  3. Dosimetry modeling of inhaled toxic reactive gases

    SciTech Connect

    Overton, J.H.; Miller, F.J.

    1986-07-01

    This report focuses on the physical, chemical, and biological processes and factors involved in the absorption of reactive gases. Emphasis is placed on the importance of these factors in developing dosimetry models, special consideration being given to the role of lung fluids and tissues. Several dosimetry models are discussed and illustrations of predicted results presented to demonstrate the application of the models to the uptake of NO/sub 2/ and O/sub 3/, and to demonstrate the use of models in determining the effects of physical, chemical and biological parameters on dosimetry predictions. Gaps in our knowledge and understanding of the processes of dosimetry are pointed out, and research recommendations are made to increase our understanding of the processes and to enhance the development of dosimetry models.

  4. Ozone dosimetry predictions for humans and rats

    SciTech Connect

    Overton, J.H.; Graham, R.C.; McCurdy, T.R.; Richmond, H.M.

    1990-11-01

    The report summarizes ozone (O3) dosimetry model predictions for rats and humans under several different scenarios based on the most recent empirical data and theoretical considerations in the field of O3 dosimetry. The report was prepared at the request of the Office of Air Quality Planning and Standards (OAQPS) as an input to be considered by scientists participating in a chronic lung injury risk assessment project for O3. As indicated in the report a number of judgments and assumptions had to be made to obtain the dosimetry predictions. In addition to presenting the simulation results, the O3 dosimetry model used to make the predictions is discussed and the choice or method of selecting important physiological parameters explained. This includes anatomical dimensions, choices of rat and human ventilatory parameters, and the method of estimating human and rat upper respiratory tract uptake. Finally, a comparison of simulation results to recent experimental dosimetry results is discussed.

  5. Marrow fat composition in anorexia nervosa

    PubMed Central

    Bredella, Miriam A.; Fazeli, Pouneh K.; Daley, Scott M.; Miller, Karen K.; Rosen, Clifford J.; Klibanski, Anne; Torriani, Martin

    2014-01-01

    Purpose Women with anorexia nervosa (AN) have increased marrow fat despite severe depletion of body fat. Recent studies have suggested that marrow fat composition may serve as a biomarker for bone quality. The purpose of our study was to investigate marrow fat composition of the femur using proton MR spectroscopy (1H-MRS), and the relationship between measures of marrow fat composition and BMD and body composition in women with AN and normal-weight controls. Materials and Methods 14 women with AN (29.5±1.9 years) and 12 age-matched normal-weight controls underwent 1H-MRS to determine total marrow fat content and marrow fat composition of the femoral diaphysis and soleus intramyocellular lipids und unsaturated muscle lipids. MRI was performed to quantify abdominal fat, thigh fat and muscle. Lumbar spine BMD, fat and lean mass were assessed by DXA. Results Subjects with AN had higher marrow fat content (p<0.05), but similar marrow fat composition (p >0.05) compared to normal-weight controls. There was an inverse association between marrow methylene protons, an estimate of fatty acid (FA) saturated bonds, and lumbar spine BMD (r= -0.52, p=0.008) independent of %ideal body weight (%IBW). Olefinic protons at 5.3 ppm, an estimate of FA unsaturated bonds, were inversely associated with body fat depots, independent of %IBW, and positively associated with soleus unsaturation (p≤0.05). Conclusion Women with AN have higher total femoral marrow fat but similar composition compared to normal-weight controls. The degree of marrow FA saturation correlates inversely with BMD, suggesting that saturated lipids may have negative effects on BMD. The degree of marrow FA unsaturation correlates positively with soleus unsaturation, suggesting that marrow fat composition may be influenced by the same factors as ectopic lipid composition in muscle. PMID:24953711

  6. Evaluation of iron status: zinc protoporphyrin vis-a-vis bone marrow iron stores.

    PubMed

    Das, Sheila; Philip, Kandathil Joseph

    2008-01-01

    Zinc protoporphyrin (ZPP) in the red cells is an indicator of iron status in the bone marrow (BM) and can be easily measured by Protofluor-Z Hematofluorometer from Helena Laboratories. It is well known that bone marrow iron is a gold standard for the diagnosis of iron deficiency anemia (IDA) even in the pre-latent phase. Hence, it was considered pertinent to evaluate the diagnostic utility of ZPP in comparison with bone marrow iron stores. 107 random BM were selected over a period of 2(1/2) years; in each case, RBC indices where recorded along with ZPP and Perls' Prussian blue reaction for BM iron stores. The specificity and sensitivity were found to be 77.8% and sensitivity 69.8%, respectively. However, the sensitivity increased up to 96.2% when Hb, RBC indices and ZPP were considered for the diagnosis of IDA. PMID:18417877

  7. Solid-State Personal Dosimetry

    NASA Technical Reports Server (NTRS)

    Wrbanek, John D.; Fralick, Gustave C.; Wrbanek, Susan Y.

    2005-01-01

    This document is a web site page, and a data sheet about Personal protection (i.e., space suits) presented to the Radiation and Micrometeoroid Mitigation Technology Focus Group meeting. The website describes the work of the PI to improve solid state personal radiation dosimetry. The data sheet presents work on the active personal radiation detection system that is to provide real-time local radiation exposure information during EVA. Should undue exposure occur, knowledge of the dynamic intensity conditions during the exposure will allow more precise diagnostic assessment of the potential health risk to the exposed individual.

  8. The Future of Medical Dosimetry

    SciTech Connect

    Adams, Robert D.

    2015-07-01

    The world of health care delivery is becoming increasingly complex. The purpose of this manuscript is to analyze current metrics and analytically predict future practices and principles of medical dosimetry. The results indicate five potential areas precipitating change factors: a) evolutionary and revolutionary thinking processes, b) social factors, c) economic factors, d) political factors, and e) technological factors. Outcomes indicate that significant changes will occur in the job structure and content of being a practicing medical dosimetrist. Discussion indicates potential variables that can occur within each process and change factor and how the predicted outcomes can deviate from normative values. Finally, based on predicted outcomes, future opportunities for medical dosimetrists are given.

  9. Patient dose analysis in total body irradiation through in vivo dosimetry.

    PubMed

    Ganapathy, K; Kurup, P G G; Murali, V; Muthukumaran, M; Bhuvaneshwari, N; Velmurugan, J

    2012-10-01

    Total body irradiation (TBI) is a special radiotherapy technique, administered prior to bone marrow transplantation. Due to the complex nature of the treatment setup, in vivo dosimetry for TBI is mandatory to ensure proper delivery of the intended radiation dose throughout the body. Lithium fluoride (LiF) TLD-100 chips are used for the TBI in vivo dosimetry. Results obtained from the in vivo dosimetry of 20 patients are analyzed. Results obtained from forehead, abdomen, pelvis, and mediastinum showed a similar pattern with the average measured dose from 96 to 97% of the prescription dose. Extremities and chest received a dose greater than the prescription dose in many instances (more than 20% of measurements). Homogeneous dose delivery to the whole body is checked by calculating the mean dose with standard deviation for each fraction. Reasons for the difference between prescription dose and measured dose for each site are discussed. Dose homogeneity within ±10% is achieved using our in-house TBI protocol. PMID:23293453

  10. Skeletal dosimetry in cone beam computed tomography.

    PubMed

    Walters, B R B; Ding, G X; Kramer, R; Kawrakow, I

    2009-07-01

    Cone beam computed tomography (CBCT) is a relatively new patient imaging technique that has proved invaluable for treatment target verification and patient positioning during image-guided radiotherapy (IGRT). It has been shown that CBCT results in additional dose to bone that may amount to 10% of the prescribed dose. In this study, voxelized human phantoms, FAX06 (adult female) and MAX06 (adult male), are used together with phase-space data collected from a realistic model of a CBCT imager to calculate dose in the red bone marrow (RBM) and bone surface cells (BSCs), the two organs at risk within the bone spongiosa, during simulated head and neck, chest and pelvis CBCT scans. The FAX06/MAX06 phantoms model spongiosa based on micro-CT images, filling the relevant phantom voxels, which are 0.12 x 0.12 x 0.12 cm3, with 17 x 17 x 17 microm3 microvoxels to form a micromatrix of trabecular bone and bone marrow. FAX06/ MAX06 have already been implemented in an EGSnrc-based Monte Carlo code to simulate radiation transport in the phantoms; however, this study required significant modifications of the code to allow use of phase-space data from a simulated CBCT imager as a source and to allow scoring of total dose, RBM dose and BSC dose on a voxel-by-voxel basis. In simulated CBCT scans, the BSC dose is significantly greater than the dose to other organs at risk. For example, in a simulated head and neck scan, the average BSC dose is 25% higher than the average dose to eye lens (approximately 8.3 cGy), and 80% greater than the average dose to brain (5.7 cGy). Average dose to RBM, on the other hand, is typically only approximately 50% of the average BSC dose and less than the dose to other organs at risk (54% of the dose to eye lens and 76% of dose to brain in a head and neck scan). Thus, elevated dose in bone due to CBCT results in elevated BSC dose. This is potentially of concern when using CBCT in conjunction with radiotherapy treatment. PMID:19673190

  11. Skeletal dosimetry in cone beam computed tomography

    SciTech Connect

    Walters, B. R. B.; Ding, G. X.; Kramer, R.; Kawrakow, I.

    2009-07-15

    Cone beam computed tomography (CBCT) is a relatively new patient imaging technique that has proved invaluable for treatment target verification and patient positioning during image-guided radiotherapy (IGRT). It has been shown that CBCT results in additional dose to bone that may amount to 10% of the prescribed dose. In this study, voxelized human phantoms, FAX06 (adult female) and MAX06 (adult male), are used together with phase-space data collected from a realistic model of a CBCT imager to calculate dose in the red bone marrow (RBM) and bone surface cells (BSCs), the two organs at risk within the bone spongiosa, during simulated head and neck, chest and pelvis CBCT scans. The FAX06/MAX06 phantoms model spongiosa based on micro-CT images, filling the relevant phantom voxels, which are 0.12x0.12x0.12 cm{sup 3}, with 17x17x17 {mu}m{sup 3} microvoxels to form a micromatrix of trabecular bone and bone marrow. FAX06/MAX06 have already been implemented in an EGSnrc-based Monte Carlo code to simulate radiation transport in the phantoms; however, this study required significant modifications of the code to allow use of phase-space data from a simulated CBCT imager as a source and to allow scoring of total dose, RBM dose and BSC dose on a voxel-by-voxel basis. In simulated CBCT scans, the BSC dose is significantly greater than the dose to other organs at risk. For example, in a simulated head and neck scan, the average BSC dose is 25% higher than the average dose to eye lens ({approx}8.3 cGy), and 80% greater than the average dose to brain (5.7 cGy). Average dose to RBM, on the other hand, is typically only {approx}50% of the average BSC dose and less than the dose to other organs at risk (54% of the dose to eye lens and 76% of dose to brain in a head and neck scan). Thus, elevated dose in bone due to CBCT results in elevated BSC dose. This is potentially of concern when using CBCT in conjunction with radiotherapy treatment.

  12. Pharmacokinetics, dosimetry and comparative efficacy of 188Re-liposome and 5-FU in a CT26-luc lung-metastatic mice model.

    PubMed

    Chen, Liang-Cheng; Wu, Yu-Hsien; Liu, I-Hshiang; Ho, Chung-Li; Lee, Wan-Chi; Chang, Chih-Hsien; Lan, Keng-Li; Ting, Gann; Lee, Te-Wei; Shien, Jui-Hung

    2012-01-01

    The biodistribution, pharmacokinetics, dosimetry and comparative therapeutic efficacy of intravenously administrated (188)Re-N,N-bis(2-mercaptoethyl)-N',N'-diethylethylenediamine (BMEDA)-labeled pegylated liposome ((188)Re-liposome) and 5-FU were investigated in a CT26-luc lung-metastatic model. After intravenous administration of (188)Re-liposome, tumor accumulation from the radioactivity was observed. Levels of radioactivity in tumors were maintained at steady levels (from 5.40 to 5.67 %ID/g) after 4 to 24 h. In pharmacokinetics, the AUC((0→∞)), MRT((0→∞)) and Cl of (188)Re-liposome in blood via intravenous route were 998 h %ID/ml, 28.7 h and 0.1 ml/h, respectively. The total excreted fractions of feces and urine were 0.61 and 0.26, respectively. Absorbed doses for (188)Re-liposome in the liver and red marrow were 0.31 and 0.08 mSv/MBq, respectively. Tumor-absorbed doses for (188)Re-liposome ranged from 48.4 to 1.73 mGy/MBq at 10 to 300 g tumor spheres. In therapeutic efficacy, the survival times of mice after (188)Re-liposome [80% maximum tolerated dose (MTD); 29.6 MBq], 5-FU (80% MTD; 144 mg/kg), liposome or normal saline treatments were evaluated. Consequently, radiotherapeutics of (188)Re-liposome attained a longer lifespan (increase of 34.9%; P=.005) in mice than in the normal saline group. The increase in lifespan of the (188)Re-liposome group was 2.5-fold greater than that of the 5-FU group. Therefore, intravenous administration of (188)Re-liposome could provide a benefit and it is a promising strategy for delivery of passive nanotargeted radiotherapeutics in oncology applications. PMID:21958858

  13. Retrospective dosimetry using synthesized nano-structure hydroxyapatite.

    PubMed

    Ziaie, F; Hajiloo, N; Alipour, A; Amraei, R; Mehtieva, S I

    2011-06-01

    Micro and nano-structure hydroxyapatite samples were synthesized via several different methods. The samples were characterised utilising the Fourier transmission infra-red, scanning electron microscope and X-ray diffraction methods, to find out the structure most similar to human tooth enamel, and the best method was found. The electron paramagnetic resonance (EPR) signals of the gamma-irradiated samples were measured using an EPR spectrometer system. A calibration curve was established by irradiation of the samples at four doses of 50-500 mGy. The parameters of the calibration curve, slope and intercept with dose axis are determined by linear regression analysis. This calibration curve can be used for human tooth enamel for retrospective dosimetry purposes. PMID:21131666

  14. Monoclonal gammopathy-associated pure red cell aplasia.

    PubMed

    Korde, Neha; Zhang, Yong; Loeliger, Kelsey; Poon, Andrea; Simakova, Olga; Zingone, Adriana; Costello, Rene; Childs, Richard; Noel, Pierre; Silver, Samuel; Kwok, Mary; Mo, Clifton; Young, Neal; Landgren, Ola; Sloand, Elaine; Maric, Irina

    2016-06-01

    Pure red cell aplasia (PRCA) is a rare disorder characterized by inhibition of erythroid precursors in the bone marrow and normochromic, normocytic anaemia with reticulocytopenia. Among 51 PRCA patients, we identified 12 (24%) patients having monoclonal gammopathy, monoclonal gammopathy of undetermined significance or smouldering multiple myeloma, with presence of monoclonal protein or abnormal serum free light chains and atypical bone marrow features of clonal plasmacytosis, hypercellularity and fibrosis. Thus far, three patients treated with anti-myeloma based therapeutics have responded with reticulocyte recovery and clinical transfusion independence, suggesting plasma cells play a key role in the pathogenesis of this specific monoclonal gammopathy-associated PRCA. PMID:26999424

  15. Cure of murine thalassemia by bone marrow transplantation without eradication of endogenous stem cells

    SciTech Connect

    Wagemaker, G.; Visser, T.P.; van Bekkum, D.W.

    1986-09-01

    alpha-Thalassemic heterozygous (Hbath/+) mice were used to investigate the possible selective advantage of transplanted normal (+/+) hemopoietic cells. Without conditioning by total-body irradiation (TBI), infusion of large numbers of normal bone marrow cells failed to correct the thalassemic peripheral blood phenotype. Since the recipients' stem cells are normal with respect to number and differentiation capacity, it was thought that the transplanted stem cells were not able to lodge, or that they were not stimulated to proliferate. Therefore, a nonlethal dose of TBI was given to temporarily reduce endogenous stem cell numbers and hemopoiesis. TBI doses of 2 or 3 Gy followed by infusion of normal bone marrow cells proved to be effective in replacing the thalassemic red cells by normal red cells, whereas a dose of 1 Gy was ineffective. It is concluded that cure of thalassemia by bone marrow transplantation does not necessarily require eradication of thalassemic stem cells. Consequently, the objectives of conditioning regimens for bone marrow transplantation of thalassemic patients (and possibly other nonmalignant hemopoietic disorders) should be reconsidered.

  16. Health physics research reactor reference dosimetry

    SciTech Connect

    Sims, C.S.; Ragan, G.E.

    1987-06-01

    Reference neutron dosimetry is developed for the Health Physics Research Reactor (HPRR) in the new operational configuration directly above its storage pit. This operational change was physically made early in CY 1985. The new reference dosimetry considered in this document is referred to as the 1986 HPRR reference dosimetry and it replaces any and all HPRR reference documents or papers issued prior to 1986. Reference dosimetry is developed for the unshielded HPRR as well as for the reactor with each of five different shield types and configurations. The reference dosimetry is presented in terms of three different dose and six different dose equivalent reporting conventions. These reporting conventions cover most of those in current use by dosimetrists worldwide. In addition to the reference neutron dosimetry, this document contains other useful dosimetry-related data for the HPRR in its new configuration. These data include dose-distance measurements and calculations, gamma dose measurements, neutron-to-gamma ratios, ''9-to-3 inch'' ratios, threshold detector unit measurements, 56-group neutron energy spectra, sulfur fluence measurements, and details concerning HPRR shields. 26 refs., 11 figs., 31 tabs.

  17. Path forward for dosimetry cross sections

    SciTech Connect

    Griffin, P.J.; Peters, C.D.

    2011-07-01

    In the 1980's the dosimetry community embraced the need for a high fidelity quantification of uncertainty in nuclear data used for dosimetry applications. This led to the adoption of energy-dependent covariance matrices as the accepted manner of quantifying the uncertainty data. The trend for the dosimetry community to require high fidelity treatment of uncertainty estimates has continued to the current time where requirements on nuclear data are codified in standards such as ASTM E 1018. This paper surveys the current state of the dosimetry cross sections and investigates the quality of the current dosimetry cross section evaluations by examining calculated-to-experimental ratios in neutron benchmark fields. In recent years more nuclear-related technical areas are placing an emphasis on uncertainty quantification. With the availability of model-based cross sections and covariance matrices produced by nuclear data codes, some nuclear-related communities are considering the role these covariance matrices should play. While funding within the dosimetry community for cross section evaluations has been very meager, other areas, such as the solar-related astrophysics community and the US Nuclear Criticality Safety Program, have been supporting research in the area of neutron cross sections. The Cross Section Evaluation Working Group (CSEWG) is responsible for the creation and maintenance of the ENDF/B library which has been the mainstay for the reactor dosimetry community. Given the new trends in cross section evaluations, this paper explores the path forward for the US nuclear reactor dosimetry community and its use of the ENDF/B cross-sections. The major concern is maintenance of the sufficiency and accuracy of the uncertainty estimate when used for dosimetry applications. The two major areas of deficiency in the proposed ENDF/B approach are: 1) the use of unrelated covariance matrices in ENDF/B evaluations and 2) the lack of 'due consideration' of experimental data

  18. Seeing Red

    NASA Technical Reports Server (NTRS)

    2008-01-01

    This New Horizons image of Jupiter's volcanic moon Io was taken at 13:05 Universal Time during the spacecraft's Jupiter flyby on February 28, 2007. It shows the reddish color of the deposits from the giant volcanic eruption at the volcano Tvashtar, near the top of the sunlit crescent, as well as the bluish plume itself and the orange glow of the hot lava at its source. The relatively unprocessed image on the left provides the best view of the volcanic glow and the plume deposits, while the version on the right has been brightened to show the much fainter plume, and the Jupiter-lit night side of Io.

    New Horizons' color imaging of Io's sunlit side was generally overexposed because the spacecraft's color camera, the super-sensitive Multispectral Visible Imaging Camera (MVIC), was designed for the much dimmer illumination at Pluto. However, two of MVIC's four color filters, the blue and 'methane' filter (a special filter designed to map methane frost on the surface of Pluto at an infrared wavelength of 0.89 microns), are less sensitive than the others, and thus obtained some well-exposed views of the surface when illumination conditions were favorable. Because only two color filters are used, rather than the usual three, and because one filter uses infrared light, the color is only a rough approximation to what the human eye would see.

    The red color of the Tvashtar plume fallout is typical of Io's largest volcanic plumes, including the previous eruption of Tvashtar seen by the Galileo and Cassini spacecraft in 2000, and the long-lived Pele plume on the opposite side of Io. The color likely results from the creation of reddish three-atom and four-atom sulfur molecules (S3 and S4) from plume gases rich in two-atom sulfur molecules (S2 After a few months or years, the S3 and S4 molecules recombine into the more stable and familiar yellowish form of sulfur consisting of eight-atom molecules (S8), so these red deposits are only seen around recently-active Io

  19. International intercomparison for criticality dosimetry: the case of biological dosimetry.

    PubMed

    Roy, L; Buard, V; Delbos, M; Durand, V; Paillole, N; Grégoire, E; Voisin, P

    2004-01-01

    The Institute of Radiation Protection and Nuclear Safety (IRSN) organized a biological dosimetry international intercomparison with the purpose of comparing (i) dicentrics yield produced in human lymphocytes; (ii) the gamma and neutron dose estimate according to the corresponding laboratory calibration curve. The experimental reactor SILENE was used with different configurations: bare source 4 Gy, lead shield 1 and 2 Gy and a 60Co source 2 Gy. An increasing variation of dicentric yield per cell was observed between participants when there were more damages in the samples. Doses were derived from the observed dicentric rates according to the dose-effect relationship provided by each laboratory. Differences in dicentric rate values are more important than those in the corresponding dose values. The doses obtained by the participants were found to be in agreement with the given physical dose within 20%. The evaluation of the respective gamma and neutron dose was achieved only by four laboratories, with some small variations among them. PMID:15353693

  20. Fat Embolism Syndrome Secondary to Bone Marrow Necrosis in Patients with Hemoglobinopathies.

    PubMed

    Gangaraju, Radhika; Reddy, Vishnu V B; Marques, Marisa B

    2016-09-01

    Bone marrow necrosis with subsequent embolization of the fat and necrotic tissues into the systemic circulation causing fat embolism syndrome and multiorgan failure is a rare complication of patients with hemoglobinopathies. The exact etiology of this condition is not known. Because it occurs more often in patients with compound heterozygous conditions than in sickle cell disease, some patients are unaware of their predisposition. The initial symptoms are nonspecific, such as back and/or abdominal pain, fever, and fatigue, which may rapidly progress to respiratory failure and severe neurologic compromise. Common laboratory tests reveal anemia without reticulocytosis, thrombocytopenia, leukoerythroblastic picture with immature white cells and nucleated red blood cells, increased lactate dehydrogenase, high ferritin, and, sometimes increased creatinine. The diagnosis can be delayed because of an apparent lack of awareness about bone marrow necrosis with fat embolism syndrome, its rarity, and its similarities with other conditions such as thrombotic thrombocytopenic purpura. Although a bone marrow biopsy is diagnostic, waiting for it delays definitive treatment, which appears to be essential for the recovery of end-organ damage, such as neurologic and pulmonary damage. In our experience, either multiple units of red blood cell transfusion or, preferably, red cell exchange initiated promptly, is lifesaving. PMID:27598359

  1. Inherited Bone Marrow Failure Syndromes (IBMFS)

    Cancer.gov

    The NCI IBMFS Cohort Study consists of affected individuals and their immediate families in North America who have an inherited bone marrow failure syndrome (IBMFS)-either one that has been specifically identified and defined, or bone marrow failure that appears to be inherited but has not yet been clearly identified as having a genetic basis.

  2. Emerging technological bases for retrospective dosimetry.

    PubMed

    Straume, T; Anspaugh, L R; Haskell, E H; Lucas, J N; Marchetti, A A; Likhtarev, I A; Chumak, V V; Romanyukha, A A; Khrouch, V T; Gavrilin YuI; Minenko, V F

    1997-01-01

    In this article we discuss examples of challenging problems in retrospective dosimetry and describe some promising solutions. The ability to make measurements by accelerator mass spectrometry and luminescence techniques promises to provide improved dosimetry for regions of Belarus, Ukraine and Russian Federation contaminated by radionuclides from the Chernobyl accident. In addition, it may soon be possible to resolve the large neutron discrepancy in the dosimetry system for Hiroshima through novel measurement techniques that can be used to reconstruct the fast-neutron fluence emitted by the bomb some 51 years ago. Important advances in molecular cytogenetics and electron paramagnetic resonance measurements have produced biodosimeters that show potential in retrospective dosimetry. The most promising of these are the frequency of reciprocal translocations measured in chromosomes of blood lymphocytes using fluorescence in situ hybridization and the electron paramagnetic resonance signal in tooth enamel. PMID:9368303

  3. Cross sections required for FMIT dosimetry

    SciTech Connect

    Gold, R.; McElroy, W.N.; Lippincott, E.P.; Mann, F.M.; Oberg, D.L.; Roberts, J.H.; Ruddy, F.H.

    1980-05-02

    The Fusion Materials Irradiation Test (FMIT) facility, currently under construction, is designed to produce a high flux of high energy neutrons for irradiation effects experiments on fusion reactor materials. Characterization of the flux-fluence-spectrum in this rapidly varying neutron field requires adaptation and extension of currently available dosimetry techniques. This characterization will be carried out by a combination of active, passive, and calculational dosimetry. The goal is to provide the experimenter with accurate neutron flux-fluence-spectra at all positions in the test cell. Plans have been completed for a number of experimental dosimetry stations and provision for these facilities has been incorporated into the FMIT design. Overall needs of the FMIT irradiation damage program delineate goal accuracies for dosimetry that, in turn, create new requirements for high energy neutron cross section data. Recommendations based on these needs have been derived for required cross section data and accuracies.

  4. INTERSPECIES DOSIMETRY MODELS FOR PULMONARY PHARMACOLOGY

    EPA Science Inventory

    Interspecies Dosimetry Models for Pulmonary Pharmacology

    Ted B. Martonen, Jeffry D. Schroeter, and John S. Fleming

    Experimental Toxicology Division, National Health and Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, Research Triangl...

  5. Audits for advanced treatment dosimetry

    NASA Astrophysics Data System (ADS)

    Ibbott, G. S.; Thwaites, D. I.

    2015-01-01

    Radiation therapy has advanced rapidly over the last few decades, progressing from 3D conformal treatment to image-guided intensity modulated therapy of several different flavors, both 3D and 4D and to adaptive radiotherapy. The use of intensity modulation has increased the complexity of quality assurance and essentially eliminated the physicist's ability to judge the validity of a treatment plan, even approximately, on the basis of appearance and experience. Instead, complex QA devices and procedures are required at the institutional level. Similarly, the assessment of treatment quality through remote and on-site audits also requires greater sophistication. The introduction of 3D and 4D dosimetry into external audit systems must follow, to enable quality assurance systems to perform meaningful and thorough audits.

  6. Aufgaben und Genauigkeit der klinischen Dosimetrie

    NASA Astrophysics Data System (ADS)

    Krieger, Hanno

    In diesem Kapitel werden die Aufgaben der klinischen Dosimetrie für die verschiedenen radiologischen Disziplinen zusammengestellt. Die wichtigste Aufgabe ist die Messung der im bestrahlten Medium entstandenen Energiedosis für die verschiedenen Strahlungsquellen. Die am weitesten verbreitete dazu verwendete Methode ist die Dosismessung mit gasgefüllten Ionisationskammern. Im zweiten Teil des Kapitels werden die Genauigkeitsanforderungen der klinischen Dosimetrie diskutiert.

  7. Rosiglitazone Promotes Bone Marrow Adipogenesis to Impair Myelopoiesis under Stress

    PubMed Central

    Lu, Wenyi; Wang, Weimin; Wang, Shujuan; Feng, Yonghuai; Liu, Kaiyan

    2016-01-01

    Objective The therapeutic use of thiazolidinediones (TZDs) causes unwanted hematological side effects, although the underlying mechanisms of these effects are poorly understood. This study tests the hypothesis that rosiglitazone impairs the maintenance and differentiation of hematopoietic stem/progenitor cells, which ultimately leads to hematological abnormalities. Methods Mice were fed a rosiglitazone-supplemented diet or a normal diet for 6 weeks. To induce hematopoietic stress, all mice were injected once with 250 mg/kg 5-fluorouracil (5-Fu) intraperitoneally. Next, hematopoietic recovery, hematopoietic stem/progenitor cells (HSPCs) subsets, and myeloid differentiation after 5-Fu treatment were evaluated. The adipogenesis induced by rosiglitazone was assessed by histopathology and oil red O staining. The effect of adipocytes on HSPCs was studied with an in vitro co-culture system. Results Rosiglitazone significantly enhanced bone marrow adipogenesis and delayed hematopoietic recovery after 5-Fu treatment. Moreover, rosiglitazone inhibited proliferation of a granulocyte/monocyte progenitor (GMP) cell population and granulocyte/macrophage colony-stimulating factor (GM-CSF) colonies, although the proliferation and mobilization of Lin-c-kit+Sca-1+ cells (LSK) was maintained following hematopoietic stress. These effects could be partially reversed by the selective PPARγ antagonist BADGE. Finally, we demonstrated in a co-culture system that differentiated adipocytes actively suppressed the myeloid differentiation of HSPCs. Conclusion Taken together, our results demonstrate that rosiglitazone inhibits myeloid differentiation of HSPCs after stress partially by inducing bone marrow adipogenesis. Targeting the bone marrow microenvironment might be one mechanism by which rosiglitazone impairs stress-induced hematopoiesis. PMID:26895498

  8. Is hydroxyethyl starch necessary for sedimentation of bone marrow?

    PubMed

    Dijkstra-Tiekstra, Margriet J; Setroikromo, Airies C; Kraan, Marcha; Gkoumassi, Effimia; de Wildt-Eggen, Janny

    2015-02-01

    Hydroxyethyl starch (HES) is used to separate hematopoietic progenitor cells after bone marrow (BM) collection from red blood cells. The aims were to study alternatives for HAES-steril (200 kDa; not available anymore) and to optimize the sedimentation process. Using WBC-enriched product (10 × 10(9) WBC/L), instead of BM, sedimentation at 10% hematocrit using final 0.6 or 0.39% Voluven (130 kDa) or without HES appeared to be good alternatives for 0.6% HAES-steril. MNC recovery >80% and RBC depletion >90% was reached. Optimal sedimentation was reached using 110-140 mL volume. Centrifugation appeared not suitable for sedimentation. Additional testing with BM might be necessary to confirm these results. PMID:25544385

  9. A protocol for EBT3 radiochromic film dosimetry using reflection scanning

    SciTech Connect

    Papaconstadopoulos, Pavlos Hegyi, Gyorgy; Seuntjens, Jan; Devic, Slobodan

    2014-12-15

    Purpose: To evaluate the performance of the EBT3 radiochromic film dosimetry system using reflection measurements and to suggest a calibration protocol for precise and accurate reflection film dosimetry. Methods: A set of 14 Gafchromic EBT3 film pieces were irradiated to various doses ranging from 0 to 8 Gy and subsequently scanned using both the reflection and transmission mode. Scanning resolution varied from 50 to 508 dpi (0.5–0.05 mm/pixel). Both the red and green color channels of scanned images were used to relate the film response to the dose. A sensitivity, uncertainty, and accuracy analysis was performed for all scanning modes and color channels. The total uncertainty, along with the fitting and experimental uncertainty components, was identified and analyzed. A microscope resolution target was used to evaluate possible resolution losses under reflection scanning. The calibration range was optimized for reflection scanning in the low (<2 Gy) and high (>2 Gy) dose regions based on the reported results. Results: Reflection scanning using the red channel exhibited the highest sensitivity among all modes, being up to 150% higher than transmission mode in the red channel for the lowest dose level. Furthermore, there was no apparent loss in resolution between the two modes. However, higher uncertainties and reduced accuracy were observed for the red channel under reflection mode, especially at dose levels higher than 2 Gy. These uncertainties were mainly attributed to saturation effects which were translated in poor fitting results. By restricting the calibration to the 0–2 Gy dose range, the situation is reversed and the red reflection mode was superior to the transmission mode. For higher doses, the green channel in reflection mode presented comparable results to the red transmission. Conclusions: A two-color reflection scanning protocol can be suggested for EBT3 radiochromic film dosimetry using the red channel for doses less than 2 Gy and the green

  10. Uncertainty in 3D gel dosimetry

    NASA Astrophysics Data System (ADS)

    De Deene, Yves; Jirasek, Andrew

    2015-01-01

    Three-dimensional (3D) gel dosimetry has a unique role to play in safeguarding conformal radiotherapy treatments as the technique can cover the full treatment chain and provides the radiation oncologist with the integrated dose distribution in 3D. It can also be applied to benchmark new treatment strategies such as image guided and tracking radiotherapy techniques. A major obstacle that has hindered the wider dissemination of gel dosimetry in radiotherapy centres is a lack of confidence in the reliability of the measured dose distribution. Uncertainties in 3D dosimeters are attributed to both dosimeter properties and scanning performance. In polymer gel dosimetry with MRI readout, discrepancies in dose response of large polymer gel dosimeters versus small calibration phantoms have been reported which can lead to significant inaccuracies in the dose maps. The sources of error in polymer gel dosimetry with MRI readout are well understood and it has been demonstrated that with a carefully designed scanning protocol, the overall uncertainty in absolute dose that can currently be obtained falls within 5% on an individual voxel basis, for a minimum voxel size of 5 mm3. However, several research groups have chosen to use polymer gel dosimetry in a relative manner by normalizing the dose distribution towards an internal reference dose within the gel dosimeter phantom. 3D dosimetry with optical scanning has also been mostly applied in a relative way, although in principle absolute calibration is possible. As the optical absorption in 3D dosimeters is less dependent on temperature it can be expected that the achievable accuracy is higher with optical CT. The precision in optical scanning of 3D dosimeters depends to a large extend on the performance of the detector. 3D dosimetry with X-ray CT readout is a low contrast imaging modality for polymer gel dosimetry. Sources of error in x-ray CT polymer gel dosimetry (XCT) are currently under investigation and include inherent

  11. Nasopharyngeal carcinoma with bone marrow metastasis.

    PubMed

    Zen, H G; Jame, J M; Chang, A Y; Li, W Y; Law, C K; Chen, K Y; Lin, C Z

    1991-02-01

    Five of 23 patients with recurrent nasopharyngeal carcinoma (NPC) were diagnosed to have bone marrow metastasis. They all had advanced local-regional disease, and were treated with neoadjuvant chemotherapy and definitive radiotherapy after the initial diagnosis. Bone marrow metastasis developed 4-24 months later. The clinical features were anemia (5 of 5), leukopenia (3 of 5), thrombocytopenia (4 of 5), sepsis (3 of 5), tenderness of the sternum (3 of 5), and fever (4 of 5). Patients frequently had elevation of serum lactic dehydrogenase (LDH), alkaline phosphatase (ALK-P), and IgG and IgA antibody titers to Epstein-Barr viral capsid antigen when bone marrow involvement was diagnosed. However, clinical manifestations and laboratory tests were not specific. It is important that three patients had normal bone scans. All five patients had a rapid downhill course; four patients died within 23 days, and the fifth 3 months after the diagnosis of bone marrow metastasis. We concluded that bone marrow was a common metastatic site in NPC patients. Bone marrow metastasis adversely affected patients' survival and required a high index of suspicion for diagnosis. We suggested that bone marrow biopsy should be considered as a routine staging procedure in NPC patients and indicated especially when patients presented with abnormal blood counts, sepsis, bone pain, or tenderness of the sternum. It may be positive in the face of a normal bone scan. PMID:1987743

  12. In aqua vivo EPID dosimetry

    SciTech Connect

    Wendling, Markus; McDermott, Leah N.; Mans, Anton; Olaciregui-Ruiz, Igor; Pecharroman-Gallego, Raul; Sonke, Jan-Jakob; Stroom, Joep; Herk, Marcel J.; Mijnheer, Ben van

    2012-01-15

    Purpose: At the Netherlands Cancer Institute-Antoni van Leeuwenhoek Hospital in vivo dosimetry using an electronic portal imaging device (EPID) has been implemented for almost all high-energy photon treatments of cancer with curative intent. Lung cancer treatments were initially excluded, because the original back-projection dose-reconstruction algorithm uses water-based scatter-correction kernels and therefore does not account for tissue inhomogeneities accurately. The aim of this study was to test a new method, in aqua vivo EPID dosimetry, for fast dose verification of lung cancer irradiations during actual patient treatment. Methods: The key feature of our method is the dose reconstruction in the patient from EPID images, obtained during the actual treatment, whereby the images have been converted to a situation as if the patient consisted entirely of water; hence, the method is termed in aqua vivo. This is done by multiplying the measured in vivo EPID image with the ratio of two digitally reconstructed transmission images for the unit-density and inhomogeneous tissue situation. For dose verification, a comparison is made with the calculated dose distribution with the inhomogeneity correction switched off. IMRT treatment verification is performed for each beam in 2D using a 2D {gamma} evaluation, while for the verification of volumetric-modulated arc therapy (VMAT) treatments in 3D a 3D {gamma} evaluation is applied using the same parameters (3%, 3 mm). The method was tested using two inhomogeneous phantoms simulating a tumor in lung and measuring its sensitivity for patient positioning errors. Subsequently five IMRT and five VMAT clinical lung cancer treatments were investigated, using both the conventional back-projection algorithm and the in aqua vivo method. The verification results of the in aqua vivo method were statistically analyzed for 751 lung cancer patients treated with IMRT and 50 lung cancer patients treated with VMAT. Results: The improvements by

  13. A Novel Biological Dosimetry Method for Monitoring Occupational Radiation Exposure in Diagnostic and Therapeutic Wards: From Radiation Dosimetry to Biological Effects

    PubMed Central

    Heydarheydari, S.; Haghparast, A.; Eivazi, M.T.

    2016-01-01

    Background and Objective Professional radiation workers are occupationally exposed to long-term low levels of ionizing radiation. Occupational health hazards from radiation exposure, in a large occupational segment of the population, are of special concern. Biological dosimetry can be performed in addition to physical dosimetry with the aim of individual dose assessment and biological effects. Methods In this biodosimetry study, some hematological parameters have been examined in 40 exposed and 40 control subjects who were matched by gender, age and occupational records (±3 years) in Kermanshah hospitals in Iran (2013-2014). The occupational radiation dose was measured by personal dosimetry device (film badges). The data was analyzed using SPSS V.20 and statistical tests such as two-sided Student’s t-test. Results Exposed subjects had a median exposure of 0.68±1.58 mSv/year by film badge dosimetry. Radiation workers with at least a 10-year record showed lower values of Mean Hemoglobin (Hb) and Mean Corpuscular Volume (MCV) compared to the control group (p<0.05). The mean value of Red Blood Cells (RBCs) in personnel working in Radiology departments seemed to show decrease in comparison with other radiation workers. Conclusion Although the radiation absorbed doses were below the permissible limits based on the ICRP, this study showed the role of low-level chronic exposure in decreasing Hb and MCV in the blood of radiation workers with at least 10 years records. Therefore, the findings from the present study suggest that monitoring of hematological parameters of radiation workers can be useful as biological dosimeter, and also the exposed medical personnel should carefully follow the radiation protection instructions and radiation exposure should be minimized as possible. PMID:27026951

  14. Breast dosimetry in clinical mammography

    NASA Astrophysics Data System (ADS)

    Benevides, Luis Alberto Do Rego

    The objective of this study was show that a clinical dosimetry protocol that utilizes a dosimetric breast phantom series based on population anthropometric measurements can reliably predict the average glandular dose (AGD) imparted to the patient during a routine screening mammogram. In the study, AGD was calculated using entrance skin exposure and dose conversion factors based on fibroglandular content, compressed breast thickness, mammography unit parameters and modifying parameters for homogeneous phantom (phantom factor), compressed breast lateral dimensions (volume factor) and anatomical features (anatomical factor). The protocol proposes the use of a fiber-optic coupled (FOCD) or Metal Oxide Semiconductor Field Effect Transistor (MOSFET) dosimeter to measure the entrance skin exposure at the time of the mammogram without interfering with diagnostic information of the mammogram. The study showed that FOCD had sensitivity with less than 7% energy dependence, linear in all tube current-time product stations, and was reproducible within 2%. FOCD was superior to MOSFET dosimeter in sensitivity, reusability, and reproducibility. The patient fibroglandular content was evaluated using a calibrated modified breast tissue equivalent homogeneous phantom series (BRTES-MOD) designed from anthropomorphic measurements of a screening mammography population and whose elemental composition was referenced to International Commission on Radiation Units and Measurements Report 44 tissues. The patient fibroglandular content, compressed breast thickness along with unit parameters and spectrum half-value layer were used to derive the currently used dose conversion factor (DgN). The study showed that the use of a homogeneous phantom, patient compressed breast lateral dimensions and patient anatomical features can affect AGD by as much as 12%, 3% and 1%, respectively. The protocol was found to be superior to existing methodologies. In addition, the study population anthropometric

  15. [Expression of Toll-like receptors in human bone marrow mesenchymal stem cells].

    PubMed

    He, Xiao-Xia; Bai, Hai; Yang, Guo-Rong; Xue, Yong-Jie; Su, Ya-Nan

    2009-06-01

    The aim of this study was to explore the characteristics of Toll-like receptor expression in mesenchymal stem cells derived from bone marrow of healthy donor (BM-MSCs). BM-MSCs were isolated from bone marrow of healthy donor by Ficoll method. Expressions of CD34, CD45, HLA-DR, CD44 and CD71 in BM-MSCs were detected by flow cytometry. CD71 in BM-MSCs was assayed by immunocytochemistry. The adipocyte and osteoblast induction of BM-MSCs were detected by alizarin red stain and oil red stain respectively. TLR 1 - 10 mRNA levels in BM-MSCs were evaluated by semiquantitative RT-PCR. The results showed that expressions of CD34, CD45 and HLA-DR in BM-MSC were negative while the expressions of CD44 and CD71 were positive. CD71 in BM-MSCs was positive. After induced by osteoblast and adipocyte inductor, BM-MSCs were positive for alizarin red staining and oil red staining respectively. All of TLR 1 - 10 mRNA were found in BM-MSCs with high expression levels of TLR2, TLR3, TLR4, TLR7, TLR8, TLR9 and low expression levels of TLR1, TLR5, TLR6, TLR10. In conclusion, different levels of TLR 1 - 10 mRNA were expressed in BM-MSCs of healthy donor. PMID:19549390

  16. Analyzing the cellular contribution of bone marrow to fracture healing using bone marrow transplantation in mice

    SciTech Connect

    Colnot, C. . E-mail: colnotc@orthosurg.ucsf.edu; Huang, S.; Helms, J.

    2006-11-24

    The bone marrow is believed to play important roles during fracture healing such as providing progenitor cells for inflammation, matrix remodeling, and cartilage and bone formation. Given the complex nature of bone repair, it remains difficult to distinguish the contributions of various cell types. Here we describe a mouse model based on bone marrow transplantation and genetic labeling to track cells originating from bone marrow during fracture healing. Following lethal irradiation and engraftment of bone marrow expressing the LacZ transgene constitutively, wild type mice underwent tibial fracture. Donor bone marrow-derived cells, which originated from the hematopoietic compartment, did not participate in the chondrogenic and osteogenic lineages during fracture healing. Instead, the donor bone marrow contributed to inflammatory and bone resorbing cells. This model can be exploited in the future to investigate the role of inflammation and matrix remodeling during bone repair, independent from osteogenesis and chondrogenesis.

  17. Experimental verification of internal dosimetry calculations. Annual progress report

    SciTech Connect

    1980-05-01

    During the past year a dosimetry research program has been established in the School of Nuclear Engineering at the Georgia Institute of Technology. The major objective of this program has been to provide research results upon which a useful internal dosimetry system could be based. The important application of this dosimetry system will be the experimental verification of internal dosimetry calculations such as those published by the MIRD Committee.

  18. Technical Basis Document for PFP Area Monitoring Dosimetry Program

    SciTech Connect

    COOPER, J.R.

    2000-04-17

    This document describes the phantom dosimetry used for the PFP Area Monitoring program and establishes the basis for the Plutonium Finishing Plant's (PFP) area monitoring dosimetry program in accordance with the following requirements: Title 10, Code of Federal Regulations (CFR), part 835, ''Occupational Radiation Protection'' Part 835.403; Hanford Site Radiological Control Manual (HSRCM-1), Part 514; HNF-PRO-382, Area Dosimetry Program; and PNL-MA-842, Hanford External Dosimetry Technical Basis Manual.

  19. Personnel neutron dosimetry at Department of Energy facilities

    SciTech Connect

    Brackenbush, L.W.; Endres, G.W.R.; Selby, J.M.; Vallario, E.J.

    1980-08-01

    This study assesses the state of personnel neutron dosimetry at DOE facilities. A survey of the personnel dosimetry systems in use at major DOE facilities was conducted, a literature search was made to determine recent advances in neutron dosimetry, and several dosimetry experts were interviewed. It was concluded that personnel neutron dosimeters do not meet current needs and that serious problems exist now and will increase in the future if neutron quality factors are increased and/or dose limits are lowered.

  20. Skeletal dosimetry based on µCT images of trabecular bone: update and comparisons

    NASA Astrophysics Data System (ADS)

    Kramer, R.; Cassola, V. F.; Vieira, J. W.; Khoury, H. J.; de Oliveira Lira, C. A. B.; Robson Brown, K.

    2012-06-01

    Two skeletal dosimetry methods using µCT images of human bone have recently been developed: the paired-image radiation transport (PIRT) model introduced by researchers at the University of Florida (UF) in the US and the systematic-periodic cluster (SPC) method developed by researchers at the Federal University of Pernambuco in Brazil. Both methods use µCT images of trabecular bone (TB) to model spongiosa regions of human bones containing marrow cavities segmented into soft tissue volumes of active marrow (AM), trabecular inactive marrow and the bone endosteum (BE), which is a 50 µm thick layer of marrow on all TB surfaces and on cortical bone surfaces next to TB as well as inside the medullary cavities. With respect to the radiation absorbed dose, the AM and the BE are sensitive soft tissues for the induction of leukaemia and bone cancer, respectively. The two methods differ mainly with respect to the number of bone sites and the size of the µCT images used in Monte Carlo calculations and they apply different methods to simulate exposure from radiation sources located outside the skeleton. The PIRT method calculates dosimetric quantities in isolated human bones while the SPC method uses human bones embedded in the body of a phantom which contains all relevant organs and soft tissues. Consequently, the SPC method calculates absorbed dose to the AM and to the BE from particles emitted by radionuclides concentrated in organs or from radiation sources located outside the human body in one calculation step. In order to allow for similar calculations of AM and BE absorbed doses using the PIRT method, the so-called dose response functions (DRFs) have been developed based on absorbed fractions (AFs) of energy for electrons isotropically emitted in skeletal tissues. The DRFs can be used to transform the photon fluence in homogeneous spongiosa regions into absorbed dose to AM and BE. This paper will compare AM and BE AFs of energy from electrons emitted in skeletal

  1. EVA dosimetry in manned spacecraft.

    PubMed

    Thomson, I

    1999-12-01

    Extra Vehicular Activity (EVA) will become a large part of the astronaut's work on board the International Space Station (ISS). It is already well known that long duration space missions inside a spacecraft lead to radiation doses which are high enough to be a significant health risk to the crew. The doses received during EVA, however, have not been quantified to the same degree. This paper reviews the space radiation environment and the current dose limits to critical organs. Results of preliminary radiation dosimetry experiments on the external surface of the BION series of satellites indicate that EVA doses will vary considerably due to a number of factors such as EVA suit shielding, temporal fluctuations and spacecraft orbit and shielding. It is concluded that measurement of doses to crew members who engage in EVA should be done on board the spacecraft. An experiment is described which will lead the way to implementing this plan on the ISS. It is expected that results of this experiment will help future crew mitigate the risks of ionising radiation in space. PMID:10631334

  2. The bone marrow aspirate and biopsy in the diagnosis of unsuspected nonhematologic malignancy: A clinical study of 19 cases

    PubMed Central

    Ozkalemkas, Fahir; Ali, Rıdvan; Ozkocaman, Vildan; Ozcelik, Tulay; Ozan, Ulku; Ozturk, Hulya; Kurt, Ender; Evrensel, Turkkan; Yerci, Omer; Tunali, Ahmet

    2005-01-01

    Background Although bone marrow metastases can be found commonly in some malignant tumors, diagnosing a nonhematologic malignancy from marrow is not a usual event. Methods To underscore the value of bone marrow aspiration and biopsy as a short cut in establishing a diagnosis for disseminated tumors, we reviewed 19 patients with nonhematologic malignancies who initially had diagnosis from bone marrow. Results The main indications for bone marrow examination were microangiopathic hemolytic anemia (MAHA), leukoerythroblastosis (LEB) and unexplained cytopenias. Bone marrow aspiration was not diagnostic due to dry tap or inadequate material in 6 cases. Biopsy results were parallel to the cytological ones in all cases except one; however a meticulous second examination of the biopsy confirmed the cytologic diagnosis in this patient too. The most common histologic subtype was adenocarcinoma, and after all the clinical and laboratory evaluations, the primary focus was disclosed definitively in ten patients (5 stomach, 3 prostate, 1 lung, 1 muscle) and probably in four patients (3 gastrointestinal tract, 1 lung). All work up failed in five patients and these cases were classified as tumor of unknown origin (TUO). Conclusion Our series showed that anemia, thrombocytopenia, elevated red cell distribution width (RDW) and hypoproteinemia formed a uniform tetrad in patients with disseminated tumors that were diagnosed via bone marrow examination. The prognosis of patients was very poor and survivals were only a few days or weeks (except for 4 patients whose survivals were longer). We concluded that MAHA, LEB and unexplained cytopenias are strong indicators of the necessity of bone marrow examination. Because of the very short survival of many patients, all investigational procedures should be judged in view of their rationality, and should be focused on treatable primary tumors. PMID:16262899

  3. 10 CFR 835.1304 - Nuclear accident dosimetry.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false Nuclear accident dosimetry. 835.1304 Section 835.1304... Nuclear accident dosimetry. (a) Installations possessing sufficient quantities of fissile material to... nuclear accident is possible, shall provide nuclear accident dosimetry for those individuals. (b)...

  4. 10 CFR 835.1304 - Nuclear accident dosimetry.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 4 2011-01-01 2011-01-01 false Nuclear accident dosimetry. 835.1304 Section 835.1304... Nuclear accident dosimetry. (a) Installations possessing sufficient quantities of fissile material to... nuclear accident is possible, shall provide nuclear accident dosimetry for those individuals. (b)...

  5. A prototype quantitative film scanner for radiochromic film dosimetry

    SciTech Connect

    Ranade, Manisha K.; Li, Jonathan G.; Dubose, Ryan S.; Kozelka, Jakub; Simon, William E.; Dempsey, James F.

    2008-02-15

    We have developed a high resolution, quantitative, two-dimensional optical film scanner for use with a commercial high sensitivity radiochromic film (RCF) for measuring single fraction external-beam radiotherapy dose distributions. The film scanner was designed to eliminate artifacts commonly observed in RCF dosimetry. The scanner employed a stationary light source and detector with a moving antireflective glass film platen attached to a high precision computerized X-Y translation stage. An ultrabright red light emitting diode (LED) with a peak output at 633 nm and full width at half maximum (FWHM) of 16 nm was selected as the scanner light source to match the RCF absorption peak. A dual detector system was created using two silicon photodiode detectors to simultaneously measure incident and transmitted light. The LED light output was focused to a submillimeter (FWHM 0.67 mm) spot size, which was determined from a scanning knife-edge technique for measuring Gaussian optical beams. Data acquisition was performed with a 16-bit A/D card in conjunction with commercial software. The linearity of the measured densities on the scanner was tested using a calibrated neutral-density step filter. Sensitometric curves and three IMRT field scans were acquired with a spatial resolution of 1 mm for both radiographic film and RCF. The results were compared with measurements taken with a commercial diode array under identical delivery conditions. The RCF was rotated by 90 deg. and rescanned to study orientation effects. Comparison between the RCF and the diode array measurements using percent dose difference and distance-to-agreement criteria produced average passing rates of 99.0% using 3%/3 mm criteria and 96.7% using 2%/2 mm criteria. The same comparison between the radiographic film and diode array measurements resulted in average passing rates 96.6% and 91.6% for the above two criteria, respectively. No measurable light-scatter or interference scanner artifacts were observed

  6. Pure red cell aplasia in a simultaneous pancreas-kidney transplantation patient: inside the erythroblast

    PubMed Central

    Labbadia, Francesca; Salido-Fierréz, Eduardo; Majado-Martinez, Juliana; Cabañas-Perianes, Valentin; Moraleda, Jiménez José M.

    2012-01-01

    A case of pure red cell aplasia in a simultaneous kidney-pancreas transplant recipient on immunosuppressive therapy is reported here. The patient presented with anemia unresponsive to erythropoietin treatment. Bone marrow cytomorphology was highly suggestive of parvovirus pure red cell aplasia, which was confirmed with serology and polymerase chain reaction positive for parvovirus B19 DNA in peripheral blood. After the administration of intravenous immunoglobulin the anemia improved with a rising number of the reticulocytes. PMID:23087806

  7. Bone marrow lesions: A systematic diagnostic approach

    PubMed Central

    Grande, Filippo Del; Farahani, Sahar J; Carrino, John A; Chhabra, Avneesh

    2014-01-01

    Bone marrow lesions on magnetic resonance (MR) imaging are common and may be seen with various pathologies. The authors outline a systematic diagnostic approach with proposed categorization of various etiologies of bone marrow lesions. Utilization of typical imaging features on conventional MR imaging techniques and other problem-solving techniques, such as chemical shift imaging and diffusion-weighted imaging (DWI), to achieve accurate final diagnosis has been highlighted. PMID:25114392

  8. Fat embolism syndrome following bone marrow harvesting.

    PubMed

    Baselga, J; Reich, L; Doherty, M; Gulati, S

    1991-06-01

    A case of fat embolism syndrome is reported following an uncomplicated bone marrow harvest. The presenting symptoms were restlessness, shortness of breath and arterial hypoxemia. A lung perfusion scan ruled out the presence of a lung thromboembolism. The patient received supportive therapy and recovered within a few hours. We speculate that the larger gauge needle (13 vs 15) used to aspirate the bone marrow may have represented increased trauma to the iliac crest leading to fat embolism. PMID:1873595

  9. Erythropoietin stimulation decreases hepcidin expression through hematopoietic activity on bone marrow cells in mice.

    PubMed

    Sasaki, Yusuke; Noguchi-Sasaki, Mariko; Yasuno, Hideyuki; Yorozu, Keigo; Shimonaka, Yasushi

    2012-12-01

    Erythropoiesis-stimulating agents (ESA) are now central to the treatment of renal anemia and are associated with improved clinical outcomes. It is well known that erythropoietin (EPO) is a key regulator of erythropoiesis through its promotion of red blood cell production. In order to investigate the role of ESA on iron metabolism, we analyzed the regulation of the iron regulatory hormone hepcidin by ESA treatment in a bone marrow transplant model in mouse. After treating C57BL/6 mice with continuous erythropoietin receptor activator (C.E.R.A.), recombinant human epoetin-β (rhEPO), or recombinant human carbamylated epoetin-β (rhCEPO), we investigated serum hepcidin concentrations and parameters of erythropoiesis. Serum hepcidin concentrations after rhEPO treatment were analyzed in mice subjected to total body irradiation followed by bone marrow transplantation. C.E.R.A. administration caused long-term downregulation of serum hepcidin levels. Serum hepcidin levels in rhEPO-treated mice decreased significantly, whereas there was no change in rhCEPO-treated mice. The reduction in circulating hepcidin levels after rhEPO administration was not observed in irradiated mice. Finally, bone marrow transplantation recovered the response to rhEPO administration that downregulates hepcidin concentration in irradiated mice. These results indicate that ESA treatment downregulates serum hepcidin concentrations, mainly by indirect mechanisms affecting hematopoietic activity in bone marrow cells. PMID:23160767

  10. Survey of international personnel radiation dosimetry programs

    SciTech Connect

    Swaja, R.E.

    1985-04-01

    In September of 1983, a mail survey was conducted to determine the status of external personnel gamma and neutron radiation dosimetry programs at international agencies. A total of 130 agencies participated in this study including military, regulatory, university, hospital, laboratory, and utility facilities. Information concerning basic dosimeter types, calibration sources, calibration phantoms, corrections to dosimeter responses, evaluating agencies, dose equivalent reporting conventions, ranges of typical or expected dose equivalents, and degree of satisfaction with existing systems was obtained for the gamma and neutron personnel monitoring programs at responding agencies. Results of this survey indicate that to provide the best possible occupational radiation monitoring programs and to improve dosimetry accuracy in performance studies, facility dosimetrists, regulatory and standards agencies, and research laboratories must act within their areas of responsibility to become familiar with their radiation monitoring systems, establish common reporting guidelines and performance standards, and provide opportunities for dosimetry testing and evaluation. 14 references, 10 tables.

  11. Dosimetry procedures for an industrial irradiation plant

    NASA Astrophysics Data System (ADS)

    Grahn, Ch.

    Accurate and reliable dosimetry procedures constitute a very important part of process control and quality assurance at a radiation processing plant. γ-Dose measurements were made on the GBS 84 irradiator for food and other products on pallets or in containers. Chemical dosimeters wre exposed in the facility under conditions of the typical plant operation. The choice of the dosimeter systems employed was based on the experience in chemical dosimetry gained over several years. Dose uniformity information was obtained in air, spices, bulbs, feeds, cosmetics, plastics and surgical goods. Most products currently irradiated require dose uniformity which can be efficiently provided by pallet or box irradiators like GBS 84. The radiation performance characteristics and some dosimetry procedures are discussed.

  12. Czech results at criticality dosimetry intercomparison 2002.

    PubMed

    Frantisek, Spurný; Jaroslav, Trousil

    2004-01-01

    Two criticality dosimetry systems were tested by Czech participants during the intercomparison held in Valduc, France, June 2002. The first consisted of the thermoluminescent detectors (TLDs) (Al-P glasses) and Si-diodes as passive neutron dosemeters. Second, it was studied to what extent the individual dosemeters used in the Czech routine personal dosimetry service can give a reliable estimation of criticality accident exposure. It was found that the first system furnishes quite reliable estimation of accidental doses. For routine individual dosimetry system, no important problems were encountered in the case of photon dosemeters (TLDs, film badge). For etched track detectors in contact with the 232Th or 235U-Al alloy, the track density saturation for the spark counting method limits the upper dose at approximately 1 Gy for neutrons with the energy >1 MeV. PMID:15353690

  13. 3-D Imaging Based, Radiobiological Dosimetry

    PubMed Central

    Sgouros, George; Frey, Eric; Wahl, Richard; He, Bin; Prideaux, Andrew; Hobbs, Robert

    2008-01-01

    Targeted radionuclide therapy holds promise as a new treatment against cancer. Advances in imaging are making it possible to evaluate the spatial distribution of radioactivity in tumors and normal organs over time. Matched anatomical imaging such as combined SPECT/CT and PET/CT have also made it possible to obtain tissue density information in conjunction with the radioactivity distribution. Coupled with sophisticated iterative reconstruction algorithims, these advances have made it possible to perform highly patient-specific dosimetry that also incorporates radiobiological modeling. Such sophisticated dosimetry techniques are still in the research investigation phase. Given the attendant logistical and financial costs, a demonstrated improvement in patient care will be a prerequisite for the adoption of such highly-patient specific internal dosimetry methods. PMID:18662554

  14. Osteosarcoma after bone marrow transplantation.

    PubMed

    Ueki, Hideaki; Maeda, Naoko; Sekimizu, Masahiro; Tsukushi, Satoshi; Nishida, Yoshihiro; Horibe, Keizo

    2013-03-01

    Three children treated with bone marrow transplantation for acute lymphoblastic leukemia, Diamond-Blackfan anemia, and congenital amegakaryocytic thrombocytopenia developed secondary osteosarcoma in the left tibia at the age of 13, 13, and 9 years, respectively, at 51, 117, and 106 months after transplantation, respectively. Through treatment with chemotherapy and surgery, all 3 patients are alive without disease. We surveyed the literature and reviewed 10 cases of osteosarcoma after hematopoietic stem cell transplantation (SCT), including our 3 cases. Eight of the patients had received myeloablative total body irradiation before SCT. The mean interval from SCT to the onset of osteosarcoma was 6 years and 4 months, and the mean age at the onset of osteosarcoma was 14 years and 5 months. The primary site of the post-SCT osteosarcoma was the tibia in 6 of 10 cases, in contrast to de novo osteosarcoma, in which the most common site is the femur. At least 7 of the 10 patients are alive without disease. Osteosarcoma should be one of the items for surveillance in the follow-up of patients who undergo SCT. PMID:22995925

  15. Reactor Dosimetry State of the Art 2008

    NASA Astrophysics Data System (ADS)

    Voorbraak, Wim; Debarberis, Luigi; D'Hondt, Pierre; Wagemans, Jan

    2009-08-01

    Oral session 1: Retrospective dosimetry. Retrospective dosimetry of VVER 440 reactor pressure vessel at the 3rd unit of Dukovany NPP / M. Marek ... [et al.]. Retrospective dosimetry study at the RPV of NPP Greifswald unit 1 / J. Konheiser ... [et al.]. Test of prototype detector for retrospective neutron dosimetry of reactor internals and vessel / K. Hayashi ... [et al.]. Neutron doses to the concrete vessel and tendons of a magnox reactor using retrospective dosimetry / D. A. Allen ... [et al.]. A retrospective dosimetry feasibility study for Atucha I / J. Wagemans ... [et al.]. Retrospective reactor dosimetry with zirconium alloy samples in a PWR / L. R. Greenwood and J. P. Foster -- Oral session 2: Experimental techniques. Characterizing the Time-dependent components of reactor n/y environments / P. J. Griffin, S. M. Luker and A. J. Suo-Anttila. Measurements of the recoil-ion response of silicon carbide detectors to fast neutrons / F. H. Ruddy, J. G. Seidel and F. Franceschini. Measurement of the neutron spectrum of the HB-4 cold source at the high flux isotope reactor at Oak Ridge National Laboratory / J. L. Robertson and E. B. Iverson. Feasibility of cavity ring-down laser spectroscopy for dose rate monitoring on nuclear reactor / H. Tomita ... [et al.]. Measuring transistor damage factors in a non-stable defect environment / D. B. King ... [et al.]. Neutron-detection based monitoring of void effects in boiling water reactors / J. Loberg ... [et al.] -- Poster session 1: Power reactor surveillance, retrospective dosimetry, benchmarks and inter-comparisons, adjustment methods, experimental techniques, transport calculations. Improved diagnostics for analysis of a reactor pulse radiation environment / S. M. Luker ... [et al.]. Simulation of the response of silicon carbide fast neutron detectors / F. Franceschini, F. H. Ruddy and B. Petrović. NSV A-3: a computer code for least-squares adjustment of neutron spectra and measured dosimeter responses / J. G

  16. HSE performance tests for dosimetry services.

    PubMed

    Birch, R; Simpson, J A; Hedley, R P; Wardle, J

    2000-12-01

    In the United Kingdom a dosimetry service that measures and assesses whole-body or part-body doses arising from external radiation must successfully complete a performance test. Results of the performance tests for routine whole-body, routine extremity/skin and special accident dosimetry, carried out over the past six years by the AEA Technology Calibration Service at Winfrith, and DRaStaC, the AWE Calibration Service at Aldermaston, are presented. The test involves irradiating groups of dosemeters to known doses of gamma radiation and determining the bias and relative standard deviations for each dose group. The results are compared with the pass criteria specified by the UK Health and Safety Executive. For routine whole-body dosimetry, both the film badge and thermoluminescent dosemeter (TLD) perform adequately for irradiations between 0.6 and 30 mSv. For higher doses up to 250 mSv, where the slow emulsion of the film is used, the film badge shows poorer performance with a tendency to overestimate the dose. For routine extremity/skin dosimetry there is a wider spread of relative standard deviation results than is seen for routine whole-body dosimetry. This is to be expected since the results will include dosemeters that are based on 'disposable' TLDs and ones based on lithium fluoride powder in sachets. For special accident dosimetry the dosemeters are tested between 0.26 and 6 Gy. For the highest dose group the film badge invariably underestimates the true dose, whereas the TLD has a tendency to overestimate it. PMID:11140715

  17. Technical basis for internal dosimetry at Hanford

    SciTech Connect

    Sula, M.J.; Carbaugh, E.H.; Bihl, D.E.

    1991-07-01

    The Hanford Internal Dosimetry Program, administered by Pacific Northwest Laboratory for the US Department of Energy, provides routine bioassay monitoring for employees who are potentially exposed to radionuclides in the workplace. This report presents the technical basis for routine bioassay monitoring and the assessment of internal dose at Hanford. The radionuclides of concern include tritium, corrosion products ({sup 58}Co, {sup 60}Co, {sup 54}Mn, and {sup 59}Fe), strontium, cesium, iodine, europium, uranium, plutonium, and americium,. Sections on each of these radionuclides discuss the sources and characteristics; dosimetry; bioassay measurements and monitoring; dose measurement, assessment, and mitigation and bioassay follow-up treatment. 78 refs., 35 figs., 115 tabs.

  18. Practical neutron dosimetry at high energies

    SciTech Connect

    McCaslin, J.B.; Thomas, R.H.

    1980-10-01

    Dosimetry at high energy particle accelerators is discussed with emphasis on physical measurements which define the radiation environment and provide an immutable basis for the derivation of any quantities subsequently required for risk evaluation. Results of inter-laboratory dosimetric comparisons are reviewed and it is concluded that a well-supported systematic program is needed which would make possible detailed evaluations and inter-comparisons of instruments and techniques in well characterized high energy radiation fields. High-energy dosimetry is so coupled with radiation transport that it is clear their study should proceed concurrently.

  19. Applicability of Topaz Composites to Electron Dosimetry

    NASA Astrophysics Data System (ADS)

    Bomfim, K. S.; Souza, D. N.

    2010-11-01

    Thermoluminescent dosimetric topaz properties have been investigated and the results have shown that this mineral presents characteristics of a good dosimeter mainly in doses evaluation in radiotherapy with photons beams in radiotherapy. Typical applications of thermoluminescent dosimeters in radiotherapy are: in vivo dosimetry on patients (either as a routine quality assurance procedure or for dose monitoring in special cases); verification of treatment techniques; dosimetry audits; and comparisons among hospitals. The mean aim of this work was to evaluate the efficiency of topaz-Teflon pellets as thermoluminescent dosimeters in high-energy electron beams used to radiotherapy. Topaz-Teflon pellets were used as TLD.

  20. Recent progresses in tritium radioecology and dosimetry

    SciTech Connect

    Galeriu, D.; Davis, P.; Raskob, W.; Melintescu, A.

    2008-07-15

    In this paper, some aspects of recent progress in tritium radioecology and dosimetry are presented, with emphasis on atmospheric releases to terrestrial ecosystems. The processes involved in tritium transfer through the environment are discussed, together with the current status of environmental tritium models. Topics include the deposition and reemission of HT and HTO, models for the assessment of routine and accidental HTO emissions, a new approach to modeling the dynamics of tritium in mammals, the dose consequences of tritium releases and aspects of human dosimetry. The need for additional experimental data is identified, together with the attributes that would be desirable in the next generation of tritium codes. (authors)

  1. Technical basis for internal dosimetry at Hanford

    SciTech Connect

    Sula, M.J.; Carbaugh, E.H.; Bihl, D.E.

    1989-04-01

    The Hanford Internal Dosimetry Program, administered by Pacific Northwest Laboratory for the US Department of Energy, provides routine bioassay monitoring for employees who are potentially exposed to radionuclides in the workplace. This report presents the technical basis for routine bioassay monitoring and the assessment of internal dose at Hanford. The radionuclides of concern include tritium, corrosion products (/sup 58/Co, /sup 60/Co, /sup 54/Mn, and /sup 59/Fe), strontium, cesium, iodine, europium, uranium, plutonium, and americium. Sections on each of these radionuclides discuss the sources and characteristics; dosimetry; bioassay measurements and monitoring; dose measurement, assessment, and mitigation; and bioassay follow-up treatment. 64 refs., 42 figs., 118 tabs.

  2. SNL RML recommended dosimetry cross section compendium

    SciTech Connect

    Griffin, P.J.; Kelly, J.G.; Luera, T.F.; VanDenburg, J.

    1993-11-01

    A compendium of dosimetry cross sections is presented for use in the characterization of fission reactor spectrum and fluence. The contents of this cross section library are based upon the ENDF/B-VI and IRDF-90 cross section libraries and are recommended as a replacement for the DOSCROS84 multigroup library that is widely used by the dosimetry community. Documentation is provided on the rationale for the choice of the cross sections selected for inclusion in this library and on the uncertainty and variation in cross sections presented by state-of-the-art evaluations.

  3. Time to demand dosimetry for molecular radiotherapy?

    PubMed Central

    Guy, M J

    2015-01-01

    Molecular radiotherapy (MRT) has been used clinically for around 75 years. Despite this long history of clinical use, there is no established dosimetry practice for calculating the absorbed dose delivered to tumour targets or to organs at risk. As a result, treatment protocols have often evolved based on experience with relatively small numbers of patients, each receiving a similar administered activity but, potentially, widely varying doses. This is in stark contrast to modern external-beam radiotherapy practice. This commentary describes some of the barriers to MRT dosimetry and gives some opinions on the way forward. PMID:25571916

  4. Celiac disease with pure red cell aplasia: an unusual hematologic association in pediatric age group.

    PubMed

    Chatterjee, Sitangshu; Dey, Pranab Kumar; Roy, Pratyay; Sinha, Malay Kumar

    2014-09-01

    Anemia in Celiac disease (CD) is usually hypoproliferative, reflecting impaired absorption of essential nutrients like iron and various vitamins. We report a 2-year-old boy with Celiac disease and severe anemia due to pure red cell aplasia, diagnosed by bone marrow biopsy. This rare, unexplained extra digestive manifestation responded to gluten free diet. PMID:25332626

  5. An automated voxelized dosimetry tool for radionuclide therapy based on serial quantitative SPECT/CT imaging

    SciTech Connect

    Jackson, Price A.; Kron, Tomas; Beauregard, Jean-Mathieu; Hofman, Michael S.; Hogg, Annette; Hicks, Rodney J.

    2013-11-15

    Purpose: To create an accurate map of the distribution of radiation dose deposition in healthy and target tissues during radionuclide therapy.Methods: Serial quantitative SPECT/CT images were acquired at 4, 24, and 72 h for 28 {sup 177}Lu-octreotate peptide receptor radionuclide therapy (PRRT) administrations in 17 patients with advanced neuroendocrine tumors. Deformable image registration was combined with an in-house programming algorithm to interpolate pharmacokinetic uptake and clearance at a voxel level. The resultant cumulated activity image series are comprised of values representing the total number of decays within each voxel's volume. For PRRT, cumulated activity was translated to absorbed dose based on Monte Carlo-determined voxel S-values at a combination of long and short ranges. These dosimetric image sets were compared for mean radiation absorbed dose to at-risk organs using a conventional MIRD protocol (OLINDA 1.1).Results: Absorbed dose values to solid organs (liver, kidneys, and spleen) were within 10% using both techniques. Dose estimates to marrow were greater using the voxelized protocol, attributed to the software incorporating crossfire effect from nearby tumor volumes.Conclusions: The technique presented offers an efficient, automated tool for PRRT dosimetry based on serial post-therapy imaging. Following retrospective analysis, this method of high-resolution dosimetry may allow physicians to prescribe activity based on required dose to tumor volume or radiation limits to healthy tissue in individual patients.

  6. RED-LETTER DAYS

    EPA Science Inventory

    The word "red-letter" is an adjective meaning "of special significance." It's origin is from the practice of marking Christian holy days in red letters on calendars. The "red-letter days" to which I refer occurred while I was a graduate student of ...

  7. International Federation of Red Cross and Red Crescent Societies

    MedlinePlus

    ... dignity and resilience Geneva, 14 September 2016 – The International Federation of Red Cross and Red Crescent Societies... ... News Contact us Sitemap Go to top The International Federation of Red Cross and Red Crescent Societies ( ...

  8. Dose Escalation and Dosimetry of First in Human Alpha Radioimmunotherapy with 212Pb-TCMC-trastuzumab

    PubMed Central

    Meredith, Ruby; Torgue, Julien; Shen, Sui; Fisher, Darrell R.; Banaga, Eileen; Bunch, Patty; Morgan, Desiree; Fan, Jinda; Straughn, J. Michael

    2015-01-01

    Our purpose was to study the safety, distribution, pharmacokinetics, immunogenicity and tumor response of intraperitoneal (IP) 212Pb-TCMC-trastuzumab (TCMC is S-2-(4-isothiocyantobenzl)-1, 4, 7, 10-tetraaza-1, 4, 7, 10=tetra (2-carbamoylmethl) cyclododecane) in patients with HER-2 expressing malignancy. Methods In a standard 3+3 Phase 1 design for dose escalation, 212Pb-TCMC-trastuzumab was delivered IP less than 4 hours after giving 4mg/kg IV trastuzumab to patients with peritoneal carcinomatosis who had failed standard therapies. Results Five dosage levels (7.4, 9.6, 12.6, 16.3, 21.1 MBq/m2) showed minimal toxicity at >1 year for the first group and >4 months for others. The lack of substantial toxicity was consistent with the dosimetry assessments (mean equivalent dose to marrow = 0.18 mSv/MBq). Radiation dosimetry assessment was performed using pharmacokinetics data obtained in the initial cohort (n=3). Limited redistribution of radioactivity out of the peritoneal cavity to circulating blood, which cleared via urinary excretion and no specific uptake in major organs was observed in 24 hours. Maximum serum concentration of the radiolabeled antibody was 22.9% at 24h (decay corrected to injection time) and 500 Bq/mL (decay corrected to collection time). Non-decay corrected cumulative urinary excretion was ≤6% in 24h (2.3 half lives). Dose rate measurements performed at 1m from the patient registered less than 5μSv/hr (using portable detectors) in the latest cohort, significantly less than what is normally observed using nuclear medicine imaging agents. Anti-drug antibody assays performed on serum from the first 4 cohorts were all negative. Conclusions Five dose levels of IP 212Pb-TCMC-trastuzumab treatment of patients with peritoneal carcinomatosis showed little agent related toxicity, consistent with the dosimetry calculations. PMID:25157044

  9. Personnel radiation dosimetry symposium: program and abstracts

    SciTech Connect

    Not Available

    1984-10-01

    The purpose was to provide applied and research dosimetrists with sufficient information to evaluate the status and direction of their programs relative to the latest guidelines and techniques. A technical program was presented concerning experience, requirements, and advances in gamma, beta, and neutron personnel dosimetry.

  10. 10 CFR 35.630 - Dosimetry equipment.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 1 2014-01-01 2014-01-01 false Dosimetry equipment. 35.630 Section 35.630 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Photon Emitting Remote Afterloader Units, Teletherapy... system or source traceable to the National Institute of Standards and Technology (NIST) and...

  11. 10 CFR 35.630 - Dosimetry equipment.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 1 2011-01-01 2011-01-01 false Dosimetry equipment. 35.630 Section 35.630 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Photon Emitting Remote Afterloader Units, Teletherapy... system or source traceable to the National Institute of Standards and Technology (NIST) and...

  12. 10 CFR 35.630 - Dosimetry equipment.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Dosimetry equipment. 35.630 Section 35.630 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Photon Emitting Remote Afterloader Units, Teletherapy... system or source traceable to the National Institute of Standards and Technology (NIST) and...

  13. 10 CFR 35.630 - Dosimetry equipment.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 1 2013-01-01 2013-01-01 false Dosimetry equipment. 35.630 Section 35.630 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Photon Emitting Remote Afterloader Units, Teletherapy... system or source traceable to the National Institute of Standards and Technology (NIST) and...

  14. Software for 3D radiotherapy dosimetry. Validation

    NASA Astrophysics Data System (ADS)

    Kozicki, Marek; Maras, Piotr; Karwowski, Andrzej C.

    2014-08-01

    The subject of this work is polyGeVero® software (GeVero Co., Poland), which has been developed to fill the requirements of fast calculations of 3D dosimetry data with the emphasis on polymer gel dosimetry for radiotherapy. This software comprises four workspaces that have been prepared for: (i) calculating calibration curves and calibration equations, (ii) storing the calibration characteristics of the 3D dosimeters, (iii) calculating 3D dose distributions in irradiated 3D dosimeters, and (iv) comparing 3D dose distributions obtained from measurements with the aid of 3D dosimeters and calculated with the aid of treatment planning systems (TPSs). The main features and functions of the software are described in this work. Moreover, the core algorithms were validated and the results are presented. The validation was performed using the data of the new PABIGnx polymer gel dosimeter. The polyGeVero® software simplifies and greatly accelerates the calculations of raw 3D dosimetry data. It is an effective tool for fast verification of TPS-generated plans for tumor irradiation when combined with a 3D dosimeter. Consequently, the software may facilitate calculations by the 3D dosimetry community. In this work, the calibration characteristics of the PABIGnx obtained through four calibration methods: multi vial, cross beam, depth dose, and brachytherapy, are discussed as well.

  15. A-bomb survivor dosimetry update

    SciTech Connect

    Loewe, W.E.

    1982-06-01

    A-bomb survivor data have been generally accepted as applicable. Also, the initial radiations have tended to be accepted as the dominant radiation source for all survivors. There was general acceptance of the essential reliability of both the biological effects data and the causative radiation dose values. There are considerations casting doubt on these acceptances, but very little quantification of th implied uncertainties has been attempted. The exception was A-bomb survivor dosimetry, where free-field kerma values for initial radiations were thought to be accurate to about 30%, and doses to individual survivors were treated as effectively error-free. In 1980, a major challenge to the accepted A-bomb survivor dosimetry was announced, and was quickly followed by a succession of explanations and displays showing the soundness of that challenge. In fact, a complete replacement set of free-field kerma values was provided which was suitable for use in constructing an entire new dosimetry for Hiroshima and Nagasaki. The new values showed many changes greater than the accepted 30% uncertainty. An approximate new dosimetry was indeed constructed, and used to convert existing leukemia cause-and-effect data from the old to the new dose values, by way of assessing the impact. (ERB)

  16. Dosimetry implant for treating restenosis and hyperplasia

    DOEpatents

    Srivastava, Suresh; Gonzales, Gilbert R; Howell, Roger W; Bolch, Wesley E; Adzic, Radoslav

    2014-09-16

    The present invention discloses a method of selectively providing radiation dosimetry to a subject in need of such treatment. The radiation is applied by an implant comprising a body member and .sup.117mSn electroplated at selected locations of the body member, emitting conversion electrons absorbed immediately adjacent selected locations while not affecting surrounding tissue outside of the immediately adjacent area.

  17. Protocol for emergency EPR dosimetry in fingernails

    Technology Transfer Automated Retrieval System (TEKTRAN)

    There is an increased need for after-the fact dosimetry because of the high risk of radiation exposures due to terrorism or accidents. In case of such an event, a method is needed to make measurements of dose in a large number of individuals rapidly and with sufficient accuracy to facilitate effect...

  18. Development of A-bomb survivor dosimetry

    SciTech Connect

    Kerr, G.D.

    1995-12-31

    An all important datum in risk assessment is the radiation dose to individual survivors of the bombings in Hiroshima and Nagasaki. The first set of dose estimates for survivors was based on a dosimetry system developed in 1957 by the Oak Ridge National Laboratory (ORNL). These Tentative 1957 Doses (T57D) were later replaced by a more extensive and refined set of Tentative 1965 Doses (T65D). The T65D system of dose estimation for survivors was also developed at ORNL and served as a basis for risk assessment throughout the 1970s. In the late 1970s, it was suggested that there were serious inadequacies with the T65D system, and these inadequacies were the topic of discussion at two symposia held in 1981. In early 1983, joint US- Japan research programs were established to conduct a thorough review of all aspects of the radiation dosimetry for the Hiroshima and Nagasaki A-bomb survivors. A number of important contributions to this review were made by ORNL staff members. The review was completed in 1986 and a new Dosimetry System 1986 (DS86) was adopted for use. This paper discusses the development of the various systems of A-bomb survivor dosimetry, and the status of the current DS86 system as it is being applied in the medical follow-up studies of the A-bomb survivors and their offspring.

  19. TOPICAL REVIEW Dosimetry for ion beam radiotherapy

    NASA Astrophysics Data System (ADS)

    Karger, Christian P.; Jäkel, Oliver; Palmans, Hugo; Kanai, Tatsuaki

    2010-11-01

    Recently, ion beam radiotherapy (including protons as well as heavier ions) gained considerable interest. Although ion beam radiotherapy requires dose prescription in terms of iso-effective dose (referring to an iso-effective photon dose), absorbed dose is still required as an operative quantity to control beam delivery, to characterize the beam dosimetrically and to verify dose delivery. This paper reviews current methods and standards to determine absorbed dose to water in ion beam radiotherapy, including (i) the detectors used to measure absorbed dose, (ii) dosimetry under reference conditions and (iii) dosimetry under non-reference conditions. Due to the LET dependence of the response of films and solid-state detectors, dosimetric measurements are mostly based on ion chambers. While a primary standard for ion beam radiotherapy still remains to be established, ion chamber dosimetry under reference conditions is based on similar protocols as for photons and electrons although the involved uncertainty is larger than for photon beams. For non-reference conditions, dose measurements in tissue-equivalent materials may also be necessary. Regarding the atomic numbers of the composites of tissue-equivalent phantoms, special requirements have to be fulfilled for ion beams. Methods for calibrating the beam monitor depend on whether passive or active beam delivery techniques are used. QA measurements are comparable to conventional radiotherapy; however, dose verification is usually single field rather than treatment plan based. Dose verification for active beam delivery techniques requires the use of multi-channel dosimetry systems to check the compliance of measured and calculated dose for a representative sample of measurement points. Although methods for ion beam dosimetry have been established, there is still room for developments. This includes improvement of the dosimetric accuracy as well as development of more efficient measurement techniques.

  20. Bone Marrow Injury Induced via Oxidative Stress in Mice by Inhalation Exposure to Formaldehyde

    PubMed Central

    McHale, Cliona; Li, Rui; Zhang, Luoping; Wu, Yang; Ye, Xin; Yang, Xu; Ding, Shumao

    2013-01-01

    Objective Formaldehyde, a ubiquitous environmental pollutant has been classified as a human leukemogen. However, toxicity of formaldehyde in bone marrow, the target site of leukemia induction, is still poorly understood. Methodology/Principal Findings To investigate bone marrow toxicity (bone marrow pathology, hematotoxicity) and underlying mechanisms (oxidative stress, inflammation, apoptosis) in formaldehyde-exposed mice. Male Balb/c mice were exposed to formaldehyde (0, 0.5, and 3.0 mg/m3) by nose-only inhalation for 8 hours/day, over a two week period designed to simulate a factory work schedule, with an exposure-free “weekend” on days 6 and 7, and were sacrificed on the morning of day 13. Counts of white blood cells, red blood cells and lymphocytes were significantly (p<0.05) decreased at 0.5 mg/m3 (43%, 7%, and 39%, respectively) and 3.0 mg/m3 (52%, 27%, and 43%, respectively) formaldehyde exposure, while platelet counts were significantly increased by 109% (0.5 mg/m3) and 67% (3.0 mg/m3). Biomarkers of oxidative stress (reactive oxygen species, glutathione depletion, cytochrome P450 1A1 and glutathione s-transferase theta 1 expression), inflammation (nuclear factor kappa-B, tomour necrosis factor alpha, interleukin-1 beta), and apoptosis (activity of cysteine-aspartic acid protease 3) in bone marrow tissues were induced at one or both formaldehyde doses mentioned above. Conclusions/Significance Exposure of mice to formaldehyde by inhalation induced bone marrow toxicity, and that oxidative stress, inflammation and the consequential apoptosis jointly constitute potential mechanisms of such induced toxicity. PMID:24040369

  1. The safety of intraosseous infusions: risks of fat and bone marrow emboli to the lungs.

    PubMed

    Orlowski, J P; Julius, C J; Petras, R E; Porembka, D T; Gallagher, J M

    1989-10-01

    The technique of intraosseous infusion is a life-saving emergency alternative when IV access is impossible or will be critically delayed. Concerns about its safety remain, especially concerning the risk of bone marrow and fat emboli to the lungs. We examined autopsy pulmonary specimens on two children who had received intraosseous infusions during resuscitation attempts and found an average of 0.23 to 0.71 bone marrow and fat emboli per mm2 of lung. We studied normotensive dogs with intraosseous infusions of emergency drugs and solutions into the distal femur. Three dogs were studied with each of the following emergency drugs or solutions: controls with normal saline (0.9% NaCl), epinephrine 0.01 mg/kg, NaHCO3 1 mEq/kg, CaCl 10 mg/kg, atropine 0.01 mg/kg, hydroxyethyl starch 6% in normal saline 10 mL/kg, 50% dextrose in water 0.25 g/kg, and lidocaine 1 mg/kg. Four hours after infusion, the animals were killed, and representative sections of the lung were examined with oil red-0 and hematoxylin and eosin stains for the presence of fat and bone marrow emboli. Fat and bone marrow emboli were found in all lung sections, varying from 0.11 to 4.48 emboli/mm2 lung (mean, 0.91 emboli/mm2 lung) for the emergency drugs and solutions and 0.06 to 0.53 emboli/mm2 (mean, 0.29 emboli/mm2 lung) for the controls. Analysis of variance revealed no significant difference (P = .07) in mean number of fat and bone marrow emboli per square millimeter of lung among the emergency drugs and compared with controls.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2802282

  2. Bone marrow changes in adolescent girls with anorexia nervosa.

    PubMed

    Ecklund, Kirsten; Vajapeyam, Sridhar; Feldman, Henry A; Buzney, Catherine D; Mulkern, Robert V; Kleinman, Paul K; Rosen, Clifford J; Gordon, Catherine M

    2010-02-01

    Early osteoporosis is common among adolescent girls with anorexia nervosa (AN) and may result from premature conversion of red (RM) to yellow bone marrow. We performed right knee magnetic resonance imaging (MRI) on a 1.0 T extremity scanner in 20 patients and 20 healthy controls, aged 16.2 +/- 1.6 years (mean +/- SD). Coronal T(1)-weighted (T(1)W) images and T(1) maps were generated from T(1) relaxometry images. Blinded radiologists visually assessed RM in the distal femoral and proximal tibial metaphyses in T(1)W images using a scale of signal intensity from 0 (homogeneous hyperintensity, no RM) to 4 (all dark, complete RM). Subjects with AN exhibited nearly twofold lower metaphyseal RM scores in both the femur (0.64 versus 1.22, p = .03) and tibia (0.54 versus 0.96, p = .08). In relaxometric measurements of four selected regions (femur and tibia amd epiphysis and metaphysis), subjects with AN showed higher mean epiphyseal but lower metaphyseal T(1). The net AN-control difference between epiphysis and metaphysis was 70 ms in the femur (+31 versus -35 ms, p = .02) and of smaller magnitude in the tibia. In relaxometry data from the full width of the femur adjacent to the growth plate, AN subjects showed mean T(1) consistently lower than in controls by 30 to 50 ms in virtually every part of the sampling region. These findings suggest that adolescents with AN exhibit premature conversion of hematopoietic to fat cells in the marrow of the peripheral skeleton potentially owing to adipocyte over osteoblast differentiation in the mesenchymal stem cell pool. PMID:19653811

  3. Bone Marrow Immunity and Myelodysplasia

    PubMed Central

    Lambert, Claude; Wu, Yuenv; Aanei, Carmen

    2016-01-01

    Myelodysplastic syndrome (MDS) is characterized by an ineffective hematopoiesis with production of aberrant clones and a high cell apoptosis rate in bone marrow (BM). Macrophages are in charge of phagocytosis. Innate Immune cells and specific T cells are in charge of immunosurveillance. Little is known on BM cell recruitment and activity as BM aspirate is frequently contaminated with peripheral blood. But evidences suggest an active role of immune cells in protection against MDS and secondary leukemia. BM CD8+ CD28− CD57+ T cells are directly cytotoxic and have a distinct cytokine signature in MDS, producing TNF-α, IL-6, CCL3, CCL4, IL-1RA, TNFα, FAS-L, TRAIL, and so on. These tools promote apoptosis of aberrant cells. On the other hand, they also increase MDS-related cytopenia and myelofibrosis together with TGFβ. IL-32 produced by stromal cells amplifies NK cytotoxicity but also the vicious circle of TNFα production. Myeloid-derived suppressing cells (MDSC) are increased in MDS and have ambiguous role in protection/progression of the diseases. CD33 is expressed on hematopoietic stem cells on MDS and might be a potential target for biotherapy. MDS also has impact on immunity and can favor chronic inflammation and emergence of autoimmune disorders. BM is the site of hematopoiesis and thus contains a complex population of cells at different stages of differentiation from stem cells and early engaged precursors up to almost mature cells of each lineage including erythrocytes, megakaryocytes, myelo-monocytic cells (monocyte/macrophage and granulocytes), NK cells, and B cells. Monocytes and B cell finalize their maturation in peripheral tissues or lymph nodes after migration through the blood. On the other hand, T cells develop in thymus and are present in BM only as mature cells, just like other well vascularized tissues. BM precursors have a strong proliferative capacity, which is usually associated with a high risk for genetic errors, cell dysfunction, and

  4. Impact of bone marrow on respiratory disease.

    PubMed

    Rankin, Sara M

    2008-06-01

    The bone marrow is not only a site of haematopoiesis but also serves as an important reservoir for mature granulocytes and stem cells, including haematopoietic stem cells, mesenchymal stem cells and fibrocytes. In respiratory diseases, such as asthma and idiopathic pulmonary fibrosis these cells are mobilised from the bone marrow in response to blood-borne mediators and subsequently recruited to the lungs. Although the granulocytes contribute to the inflammatory reaction, stem cells may promote tissue repair or remodelling. Understanding the factors and molecular mechanisms that regulate the mobilisation of granulocytes and stem cells from the bone marrow may lead to the identification of novel therapeutic targets for the treatment of a wide range of respiratory disorders. PMID:18372214

  5. Pure Red Cell Aplasia Following Interleukin-2 Therapy

    PubMed Central

    Dutcher, Janice P.; Fan, Wen; Wiernik, Peter H.

    2016-01-01

    A 61-year-old woman with metastatic renal cell carcinoma underwent systemic treatment with high-dose interleukin-2 (IL-2). Anemia requiring transfusion of 1 unit of packed red blood cells (PRBCs) was required during the second week of IL-2 therapy. One month following completion of high-dose IL-2 treatment, she was hospitalized for severe, symptomatic anemia and received 5 units of PRBCs. She was referred back for evaluation. A complete hematologic evaluation was performed including antiviral serology, evaluation for hemolysis, complete iron studies, and finally bone marrow aspiration and biopsy. The diagnosis was pure red cell aplasia, and no inciting viral cause could be ascertained. She required PRBCs for 5 months following IL-2 therapy. It was concluded that IL-2 was the cause of her red cell aplasia. This subsequently resolved spontaneously, and she had normal hemoglobin and hematocrit, respectively, 1 and 2 years after treatment. PMID:27144182

  6. Cell survival kinetics in peripheral blood and bone marrow during total body irradiation for marrow transplantation

    SciTech Connect

    Shank, B.; Andreeff, M.; Li, D.

    1983-11-01

    Cell survival kinetics in both peripheral blood and in bone marrow have been studied over the time course of hyperfractionated total body irradiation (TBI) for bone marrow transplantation. Our unique TBI regimen allows the study of the in vivo radiation effect uncomplicated by prior cyclophosphamide, since this agent is given after TBI in our cytoreduction scheme. Peripheral blood cell concentrations were monitored with conventional laboratory cell counts and differentials. Absolute bone marrow cell concentrations were monitored by measuring cell concentrations in an aspirate sample and correcting for dilution with blood by a cell cycle kinetic method using cytofluorometry. For lymphocytes in peripheral blood in patients in remission, the effective D/sub 0/ ranged from 373 rad in 10 children less than or equal to 10 y old, to 536 rad in the four patients between 11 to 17 y old, while n = 1.0 in all groups. There was no trend observed according to age. Granulocytes had a much higher effective D/sub 0/, approximately 1000 rad in vivo. Absolute nucleated cell concentration in marrow dropped slowly initially, due to an increased lymphocyte concentration in marrow during a concurrent drop in lymphocyte concentration in peripheral blood, but eventually fell on the last day of TBI ranging from 7 to 44% of the initial marrow nucleated cell concentration. Marrow myeloid elements, however, dropped continuously throughout the course of TBI.

  7. Bone Marrow Stress Decreases Osteogenic Progenitors.

    PubMed

    Ng, Adeline H; Baht, Gurpreet S; Alman, Benjamin A; Grynpas, Marc D

    2015-11-01

    Age-related bone loss may be a result of declining levels of stem cells in the bone marrow. Using the Col2.3Δtk (DTK) transgenic mouse, osteoblast depletion was used as a source of marrow stress in order to investigate the effects of aging on osteogenic progenitors which reside in the marrow space. Five-month-old DTK mice were treated with one or two cycles of ganciclovir to conditionally ablate differentiated osteoblasts, whereas controls were saline-treated. Treatment cycles were two weeks in length followed by four weeks of recovery. All animals were sacrificed at 8 months of age; bone marrow stromal cells (BMSCs) were harvested for cell culture and whole bones were excised for bone quality assessment. Colony-forming unit (CFU) assays were conducted to investigate the osteogenic potential of BMSC in vitro, and RNA was extracted to assess the expression of osteoblastic genes. Bone quality assessments included bone histomorphometry, TRAP staining, microcomputed tomography, and biomechanical testing. Osteoblast depletion decreased CFU-F (fibroblast), CFU-ALP (alkaline phosphatase), and CFU-VK (von Kossa) counts and BMSC osteogenic capacity in cell culture. Ex vivo, there were no differences in bone mineral density of vertebrae or femurs between treatment groups. Histology showed a decrease in bone volume and bone connectivity with repeated osteoblast depletion; however, this was accompanied by an increase in bone formation rate. There were no notable differences in osteoclast parameters or observed bone marrow adiposity. We have developed a model that uses bone marrow stress to mimic age-related decrease in osteogenic progenitors. Our data suggest that the number of healthy BMSCs and their osteogenic potential decline with repeated osteoblast depletion. However, activity of the remaining osteoblasts increases to compensate for this loss in progenitor osteogenic potential. PMID:26220824

  8. A method for multichannel dosimetry with EBT3 radiochromic films

    SciTech Connect

    Pérez Azorín, Jose Fernando

    2014-06-15

    Purpose: An improved method for multichannel dosimetry is presented. This method explicitly takes into account the information provided by the unexposed image of the film. Methods: The method calculates the dose by applying a couple of perturbations to the scanned dose, one dependent and the other independent on the color channel. The method has been compared with previous multichannel and two single channel methods (red and green) against measurements using two different tests: first, five percentage depth dose profiles covering a wide range of doses; second, the dose map perpendicular to the beam axis for a 15 × 15cm{sup 2} square field. Finally, the results of 30 IMRT quality assurances tests are presented. All tests have been evaluated using the gamma analysis. Results: The coefficient of variation was found to be similar for all methods in a wide range of doses. The results of the proposed method are more in agreement with the experimental measurements and with the treatment planning system. Furthermore, the differences in the mean gamma pass rates are statistically significant. Conclusions: The improved multichannel dosimetric method is able to remove many of the common disturbances usually present in radiochromic films and improves the gamma analysis results compared with the other three methods.

  9. Marrow-tumor interactions: the role of the bone marrow in controlling chemically induced tumors

    SciTech Connect

    Rosse, C

    1980-01-01

    This report summarizes work done to evaluate the role of the bone marrow in tumor growth regulation. Work done with the MCA tumor showed that several subclasses of mononuclear bone marrow cells (e.g. natural regulatory cell, NRC) play a major role in the regulation of tumor growth. Experiments with the spontaneous CE mammary carcinoma system illustrate that a rapid growth of certain neoplasms may be due to the fact that through some as yet undefined mechanism the tumor eliminates mononuclear cells in the bone marrow of the host and stops their production. (KRM)

  10. Tactical gamma and fast neutron dosimetry with leuko dye optical waveguides. Conference paper

    SciTech Connect

    Kronenberg, S.

    1982-06-18

    Ionizing radiation-induced changes in the refractive index of radiochromic dye solution results in a novel dosimetry system with a very wide dynamic range. This approach is adaptable to personnel dosimetry and to Army tactical dosimetry.

  11. Comparative morphology of the marrow sac.

    PubMed

    Bi, L X; Simmons, D J; Hawkins, H K; Cox, R A; Mainous, E G

    2000-12-01

    Electron microscopic techniques have been used to profile the morphologies of marrow sacs in different laboratory species. These structures all comprise a condensed layer of overlapping fibroblast-like stromal cells and apparently confine the medullary and endosteal osteoblast/lining cells to separate histiotypic compartments. There were some variations in the morphology of the sac cells in the different species. In rats, cats, and sheep, scanning electron microscopy (SEM) showed a seamless arrangement of marrow sac cells which resembled a thin, flat simple squamous epithelium; they displayed few intercellular cytoplasmic processes. In the rabbit and pigeon, the sac comprised a more woven, multilayered fabric of broadly elongate flat fibroblast-like cells which displayed numerous intercellular processes. Transmission electron microscopy (TEM) showed that all marrow sac cells were attenuated with elongated nuclei, a few small round mitochondria, and a sparse rough endoplasmic reticulum. In the majority of animals, the sac was one to two cell layers thick. The rabbit and pigeon sacs were multilayered, and never less than three to four cells deep. The cell layers were not closely apposed. Tight or gap junctions were absent at the points of intercellular contact. These morphological results suggest that marrow sacs are common elements of the vertebrate skeleton with species specific morphologies. PMID:11074407

  12. Marrow cells as progenitors of lung tissue.

    PubMed

    Fine, Alan

    2004-01-01

    There is accumulating evidence showing that marrow-derived cells can engraft as differentiated epithelial cells of various tissues, including the lung. These findings challenge long-held views regarding the basic biology of stem cells. Elucidating the fundamental mechanisms controlling these processes is the major challenge of this field. Regardless, these experiments suggest new strategies for the treatment of chronic diseases. PMID:14757420

  13. An investigation of false positive dosimetry results

    SciTech Connect

    Lewandowski, M.A.; Davis, S.A.; Goff, T.E.; Wu, C.F.

    1996-12-31

    The Waste Isolation Pilot Plant (WIPP) is a facility designed for the demonstration of the safe disposal of transuranic waste. Currently, the radiation source term is confined to sealed calibration and check sources since WIPP has not received waste for disposal. For several years the WIPP Dosimetry Group has operated a Harshaw Model 8800C reader to analyze Harshaw 8801-7776 thermoluminescent cards (3 TLD-700 and 1 TLD-600) with 8805 holder. The frequency of false positive results for quarterly dosimeter exchanges is higher than desired by the Dosimetry Group management. Initial observations suggested that exposure to intense ambient sunlight may be responsible for the majority of the false positive readings for element 3. A study was designed to investigate the possibility of light leaking through the holder and inducing a signal in element 3. This paper discusses the methods and results obtained, with special emphasis placed on recommendations to reduce the frequency of light-induced false positive readings.

  14. Neutron dosimetry using optically stimulated luminescence

    NASA Astrophysics Data System (ADS)

    Miller, S. D.; Eschbach, P. A.

    1991-06-01

    The addition of thermoluminescent (TL) materials within hydrogenous matrices to detect neutron induced proton recoils for radiation dosimetry is a well known concept. Previous attempts to implement this technique have met with limited success, primarily due to the high temperatures required for TL readout and the low melting temperatures of hydrogen-rich plastics. Research in recent years PNL has produced a new Optically Stimulated Luminescence (OSL) technique known as the Cooled Optically Stimulated Luminescence (COSL) that offers, for the first time, the capability of performing extremely sensitive radiation dosimetry at low temperatures. In addition to its extreme sensitivity, the COSL technique offers multiple readout capability, limited fading in a one year period, and the capability of analyzing single grains within a hydrogenous matrix.

  15. Passive particle dosimetry. [silver halide crystal growth

    NASA Technical Reports Server (NTRS)

    Childs, C. B.

    1977-01-01

    Present methods of dosimetry are reviewed with emphasis on the processes using silver chloride crystals for ionizing particle dosimetry. Differences between the ability of various crystals to record ionizing particle paths are directly related to impurities in the range of a few ppm (parts per million). To understand the roles of these impurities in the process, a method for consistent production of high purity silver chloride, and silver bromide was developed which yields silver halides with detectable impurity content less than 1 ppm. This high purity silver chloride was used in growing crystals with controlled doping. Crystals were grown by both the Czochalski method and the Bridgman method, and the Bridgman grown crystals were used for the experiments discussed. The distribution coefficients of ten divalent cations were determined for the Bridgman crystals. The best dosimeters were made with silver chloride crystals containing 5 to 10 ppm of lead; other impurities tested did not produce proper dosimeters.

  16. Absolute and relative dosimetry for ELIMED

    SciTech Connect

    Cirrone, G. A. P.; Schillaci, F.; Scuderi, V.; Cuttone, G.; Candiano, G.; Musumarra, A.; Pisciotta, P.; Romano, F.; Carpinelli, M.; Presti, D. Lo; Raffaele, L.; Tramontana, A.; Cirio, R.; Sacchi, R.; Monaco, V.; Marchetto, F.; Giordanengo, S.

    2013-07-26

    The definition of detectors, methods and procedures for the absolute and relative dosimetry of laser-driven proton beams is a crucial step toward the clinical use of this new kind of beams. Hence, one of the ELIMED task, will be the definition of procedures aiming to obtain an absolute dose measure at the end of the transport beamline with an accuracy as close as possible to the one required for clinical applications (i.e. of the order of 5% or less). Relative dosimetry procedures must be established, as well: they are necessary in order to determine and verify the beam dose distributions and to monitor the beam fluence and the energetic spectra during irradiations. Radiochromic films, CR39, Faraday Cup, Secondary Emission Monitor (SEM) and transmission ionization chamber will be considered, designed and studied in order to perform a fully dosimetric characterization of the ELIMED proton beam.

  17. Neutron dosimetry using optically stimulated luminescence

    SciTech Connect

    Miller, S.D.; Eschbach, P.A.

    1991-06-01

    The addition of thermoluminescent (TL) materials within hydrogenous matrices to detect neutron-induced proton recoils for radiation dosimetry is a well-known concept. Previous attempts to implement this technique have met with limited success, primarily due to the high temperatures required for TL readout and the low melting temperatures of hydrogen-rich plastics. Research in recent years at Pacific Northwest laboratories (PNL) has produced a new Optically Stimulated Luminescence (OSL) technique known as the Cooled Optically Stimulated Luminescence (COSL) that offers, for the first time, the capability of performing extremely sensitive radiation dosimetry at low temperatures. In addition to its extreme sensitivity, the COSL technique offers multiple readout capability, limited fading in a one-year period, and the capability of analyzing single grains within a hydrogenous matrix. 4 refs., 10 figs.

  18. Trigeminal neuralgia treatment dosimetry of the Cyberknife

    SciTech Connect

    Ho, Anthony; Lo, Anthony T.; Dieterich, Sonja; Soltys, Scott G.; Gibbs, Iris C.; Chang, Steve G.; Adler, John R.

    2012-04-01

    There are 2 Cyberknife units at Stanford University. The robot of 1 Cyberknife is positioned on the patient's right, whereas the second is on the patient's left. The present study examines whether there is any difference in dosimetry when we are treating patients with trigeminal neuralgia when the target is on the right side or the left side of the patient. In addition, we also study whether Monte Carlo dose calculation has any effect on the dosimetry. We concluded that the clinical and dosimetric outcomes of CyberKnife treatment for trigeminal neuralgia are independent of the robot position. Monte Carlo calculation algorithm may be useful in deriving the dose necessary for trigeminal neuralgia treatments.

  19. Peripheral red blood cell split chimerism as a consequence of intramedullary selective apoptosis of recipient red blood cells in a case of sickle cell disease.

    PubMed

    Marziali, Marco; Isgrò, Antonella; Sodani, Pietro; Gaziev, Javid; Fraboni, Daniela; Paciaroni, Katia; Gallucci, Cristiano; Alfieri, Cecilia; Roveda, Andrea; De Angelis, Gioia; Cardarelli, Luisa; Ribersani, Michela; Andreani, Marco; Lucarelli, Guido

    2014-01-01

    Allogeneic cellular gene therapy through hematopoietic stem cell transplantation is the only radical cure for congenital hemoglobinopathies like thalassemia and sickle cell anemia. Persistent mixed hematopoietic chimerism (PMC) has been described in thalassemia and sickle cell anemia. Here, we describe the clinical course of a 6-year-old girl who had received bone marrow transplant for sickle cell anemia. After the transplant, the patient showed 36% donor hematopoietic stem cells in the bone marrow, whereas in the peripheral blood there was evidence of 80% circulating donor red blood cells (RBC). The analysis of apoptosis at the Bone Marrow level suggests that Fas might contribute to the cell death of host erythroid precursors. The increase in NK cells and the regulatory T cell population observed in this patient suggests that these cells might contribute to the condition of mixed chimerism. PMID:25408852

  20. Peripheral Red Blood Cell Split Chimerism as a Consequence of Intramedullary Selective Apoptosis of Recipient Red Blood Cells in a Case of Sickle Cell Disease

    PubMed Central

    Marziali, Marco; Isgrò, Antonella; Sodani, Pietro; Gaziev, Javid; Fraboni, Daniela; Paciaroni, Katia; Gallucci, Cristiano; Alfieri, Cecilia; Roveda, Andrea; De Angelis, Gioia; Cardarelli, Luisa; Ribersani, Michela; Andreani, Marco; Lucarelli, Guido

    2014-01-01

    Allogeneic cellular gene therapy through hematopoietic stem cell transplantation is the only radical cure for congenital hemoglobinopathies like thalassemia and sickle cell anemia. Persistent mixed hematopoietic chimerism (PMC) has been described in thalassemia and sickle cell anemia. Here, we describe the clinical course of a 6-year-old girl who had received bone marrow transplant for sickle cell anemia. After the transplant, the patient showed 36% donor hematopoietic stem cells in the bone marrow, whereas in the peripheral blood there was evidence of 80% circulating donor red blood cells (RBC). The analysis of apoptosis at the Bone Marrow level suggests that Fas might contribute to the cell death of host erythroid precursors. The increase in NK cells and the regulatory T cell population observed in this patient suggests that these cells might contribute to the condition of mixed chimerism. PMID:25408852

  1. Hanford External Dosimetry Technical Basis Manual PNL-MA-842

    SciTech Connect

    Rathbone, Bruce A.

    2005-02-25

    The Hanford External Dosimetry Technical Basis Manual PNL-MA-842 documents the design and implementation of the external dosimetry system used at Hanford. The manual describes the dosimeter design, processing protocols, dose calculation methodology, radiation fields encountered, dosimeter response characteristics, limitations of dosimeter design under field conditions, and makes recommendations for effective use of the dosimeters in the field. The manual describes the technical basis for the dosimetry system in a manner intended to help ensure defensibility of the dose of record at Hanford and to demonstrate compliance with 10 CFR 835, DOELAP, DOE-RL, ORP, PNSO, and Hanford contractor requirements. The dosimetry system is operated by PNNL’s Hanford External Dosimetry Program which provides dosimetry services to all Hanford contractors. The primary users of this manual are DOE and DOE contractors at Hanford using the dosimetry services of PNNL. Development and maintenance of this manual is funded directly by DOE and DOE contractors. Its contents have been reviewed and approved by DOE and DOE contractors at Hanford through the Hanford Personnel Dosimetry Advisory Committee which is chartered and chaired by DOE-RL and serves as means of coordinating dosimetry practices across contractors at Hanford. This manual was established in 1996. Since inception, it has been revised many times and maintained by PNNL as a controlled document with controlled distribution. Rev. 0 marks the first revision to be released through PNNL’s Electronic Records & Information Capture Architecture (ERICA) database.

  2. Simple optical theory for light dosimetry during PDT (Invited Paper)

    NASA Astrophysics Data System (ADS)

    Jacques, Steven L.

    1992-06-01

    Photons are one of the three major reactants in the photodynamic reaction that yields toxic photoproduct for cell killing. Dosimetry of light is a major concern when planning a photodynamic therapy (PDT) protocol. This paper presents a very simple approach toward the tissue optics with a practical conclusion about how tissue optics affects planning of day-to-day PDT dosimetry. The paper does not address all the complexities of real tissue dosimetry, such as heterogeneous tissues, variable absorption due to changing tissue blood content, and variable tissue oxygen levels. The paper outlines the optical behavior in a homogeneous tissue, which is a starting point for understanding light dosimetry.

  3. Energy Metabolism and Human Dosimetry of Tritium

    SciTech Connect

    Galeriu, D.; Takeda, H.; Melintescu, A.; Trivedi, A

    2005-07-15

    In the frame of current revision of human dosimetry of {sup 14}C and tritium, undertaken by the International Commission of Radiological Protection, we propose a novel approach based on energy metabolism and a simple biokinetic model for the dynamics of dietary intake (organic {sup 14}C, tritiated water and Organically Bound Tritium-OBT). The model predicts increased doses for HTO and OBT comparing to ICRP recommendations, supporting recent findings.

  4. Quantities and units in radiation protection dosimetry

    NASA Astrophysics Data System (ADS)

    Jennings, W. A.

    1994-08-01

    A new report, entitled Quantities and Units in Radiation Protection Dosimetry, has recently been published by the international Commission on Radiation Units and Measurements. That report (No. 51) aims to provide a coherent system of quantities and units for purposes of measurement and calculation in the assessment of compliance with dose limitations. The present paper provides an extended summary of that report, including references to the operational quantities needed for area and individual monitoring of external radiations.

  5. a Generalized Program for Internal Radionuclide Dosimetry

    NASA Astrophysics Data System (ADS)

    Johnson, Timothy Karl

    The development of monoclonal antibodies specific for tumor surface antigens promises a highly specific carrier medium for delivering a tumorcidal radiation dose. Dosimetry calculations of monoclonal antibodies are made difficult, however, precisely because the focus of radioactivity is targeted for a nonstandard volume in a nonstandard geometry. This precludes straightforward application of the formalism developed for internal radionuclide dosimetry by the Medical Internal Radiation Dose Committee. A software program was written to account for the perturbations introduced by the inclusion of a tumor mass as an additional source of, and target for, radiation. The program allows the interactive development of a mathematical model to account for observed biodistribution data. The model describes the time dependence of radioactivity in each organ system that retains radiolabeled antibody, including tumor. Integration of these "time-activity" curves yield cumulative activity for each organ system identified as a 'source' of radioactivity. A Monte Carlo simulation of photon transport is then executed for each source organ to obtain the fraction of radiation energy absorbed by various 'target' organs. When combined with the cumulative activity, this absorbed fraction allows an estimate of dose to be made for each target organ. The program has been validated against ten analytic models designed to span a range of common input data types. Additionally, a performance benchmark has been defined to assess the practicality of implementing the program on different computing hardware platforms. Sources of error in the computation are elaborated on, and future directions and improvements discussed. The software presents an integrated modeling/dosimetry environment particularly suited for performing Monoclonal Antibody dosimetry. It offers a viable methodology for performing prospective treatment planning, based on extrapolation of tracer kinetic data to therapeutic levels.

  6. The Importance of Dosimetry Standardization in Radiobiology

    PubMed Central

    Desrosiers, Marc; DeWerd, Larry; Deye, James; Lindsay, Patricia; Murphy, Mark K; Mitch, Michael; Macchiarini, Francesca; Stojadinovic, Strahinja; Stone, Helen

    2013-01-01

    Radiation dose is central to much of radiobiological research. Precision and accuracy of dose measurements and reporting of the measurement details should be sufficient to allow the work to be interpreted and repeated and to allow valid comparisons to be made, both in the same laboratory and by other laboratories. Despite this, a careful reading of published manuscripts suggests that measurement and reporting of radiation dosimetry and setup for radiobiology research is frequently inadequate, thus undermining the reliability and reproducibility of the findings. To address these problems and propose a course of action, the National Cancer Institute (NCI), the National Institute of Allergy and Infectious Diseases (NIAID), and the National Institute of Standards and Technology (NIST) brought together representatives of the radiobiology and radiation physics communities in a workshop in September, 2011. The workshop participants arrived at a number of specific recommendations as enumerated in this paper and they expressed the desirability of creating dosimetry standard operating procedures (SOPs) for cell culture and for small and large animal experiments. It was also felt that these SOPs would be most useful if they are made widely available through mechanism(s) such as the web, where they can provide guidance to both radiobiologists and radiation physicists, be cited in publications, and be updated as the field and needs evolve. Other broad areas covered were the need for continuing education through tutorials at national conferences, and for journals to establish standards for reporting dosimetry. This workshop did not address issues of dosimetry for studies involving radiation focused at the sub-cellular level, internally-administered radionuclides, biodosimetry based on biological markers of radiation exposure, or dose reconstruction for epidemiological studies. PMID:26401441

  7. 3D dosimetry fundamentals: gels and plastics

    NASA Astrophysics Data System (ADS)

    Lepage, M.; Jordan, K.

    2010-11-01

    Many different materials have been developed for 3D radiation dosimetry since the Fricke gel dosimeter was first proposed in 1984. This paper is intended as an entry point into these materials where we provide an overview of the basic principles for the most explored materials. References to appropriate sources are provided such that the reader interested in more details can quickly find relevant information.

  8. Comparison of bone marrow aspiration and bone marrow biopsy in neoplastic diseases.

    PubMed

    Hamid, G A; Hanbala, N

    2009-07-01

    Naturally trephine biopsies have definitive advantages over aspirates in case of dry tap bone marrow aspirates as a result of fibrosis or densely packed bone marrow by tumour cells and may be informative independent of cytology especially in bone marrow involvement by lymphomas and carcinomas. In this prospective descriptive study we aimed to compare between the bone marrow trephine biopsy (BMTB) and bone marrow aspirates (BMAs) regarding the detection rate of solid tumours, lymphoma and myeloma involvement of the bone marrow. The study was carried out in the department of pathology and Haematology-Oncology of Al-Gamhouria Teaching Hospital/Aden during the period between Jan 2005 to Dec 2005. A total of 32 patients with suspected or confirmed malignancy undergone both BMTB and BMA from the posterior superior iliac crest and both results were compared. We divided them into three groups: those with solid tumours (21) patients, lymphoma (7) patients and with MM (4) patients. Our results showed that BMA had a 47.6% sensitivity, 100.0% specificity, with positive predictive value (100%), and negative predictive value (50.0%). In solid tumours alone it had a sensitivity of (40.0%), 100% specificity, with positive predictive value (100%), and negative predictive value (64.7%). This gives the BMA a lower sensitivity in detecting solid tumour metastasis and lymphoma involvement in comparison to BMTB. In conclusion, any patient with suspected or confirmed cancer should undergo BMTB because of its high sensitivity compared to BMA. PMID:20194084

  9. Bone marrow manifestations in multicentric Castleman disease.

    PubMed

    Ibrahim, Hazem A H; Balachandran, Kirsty; Bower, Mark; Naresh, Kikkeri N

    2016-03-01

    This study aimed to document the morphological and immunophenotypic features, and describe the diagnostic features of bone marrow (BM) involvement in human herpes virus 8 Multicentric Castleman disease (HHV8-MCD). BM trephine biopsy (BMTB) specimens from 28 patients were revisited. Samples were evaluated for expression of CD3, CD20, CD138, CD68R, glycophorin C, CD42b, HHV8-latency-associated nuclear antigen (LANA1), Epstein-Barr virus-encoded small RNA and light chains. Presence of significant numbers of HHV8-LANA1(+) lymphoid/plasmacytic cells, noted in 10/28 cases, was indicative of BM involvement and was associated with low CD4 and CD8 counts in peripheral blood. The characteristic morphological appearance of MCD seen in lymph nodes is a rare finding in BMTB. 4/5 cases with lymphoid aggregates were involved by MCD, whereas 6/23 cases without lymphoid aggregates were involved by MCD (P = 0·023). 9/18 cases with hypercellular marrow were involved by MCD, whilst only 1/8 cases with normo/hypocellular marrow showed involvement by MCD (P = 0·070). While 9/21 cases with increased marrow reticulin were involved by MCD, none of the cases with no increase in reticulin were involved by MCD (P = 0·080). Reactive plasmacytosis is a frequent finding. We conclude that bone marrow is involved in a significant proportion of patients with MCD (36%), and involvement can be identified by HHV8-LANA1 immunohistochemistry. PMID:26817834

  10. Bayesian Methods for Radiation Detection and Dosimetry

    SciTech Connect

    Peter G. Groer

    2002-09-29

    We performed work in three areas: radiation detection, external and internal radiation dosimetry. In radiation detection we developed Bayesian techniques to estimate the net activity of high and low activity radioactive samples. These techniques have the advantage that the remaining uncertainty about the net activity is described by probability densities. Graphs of the densities show the uncertainty in pictorial form. Figure 1 below demonstrates this point. We applied stochastic processes for a method to obtain Bayesian estimates of 222Rn-daughter products from observed counting rates. In external radiation dosimetry we studied and developed Bayesian methods to estimate radiation doses to an individual with radiation induced chromosome aberrations. We analyzed chromosome aberrations after exposure to gammas and neutrons and developed a method for dose-estimation after criticality accidents. The research in internal radiation dosimetry focused on parameter estimation for compartmental models from observed compartmental activities. From the estimated probability densities of the model parameters we were able to derive the densities for compartmental activities for a two compartment catenary model at different times. We also calculated the average activities and their standard deviation for a simple two compartment model.

  11. Software tool for portal dosimetry research.

    PubMed

    Vial, P; Hunt, P; Greer, P B; Oliver, L; Baldock, C

    2008-09-01

    This paper describes a software tool developed for research into the use of an electronic portal imaging device (EPID) to verify dose for intensity modulated radiation therapy (IMRT) beams. A portal dose image prediction (PDIP) model that predicts the EPID response to IMRT beams has been implemented into a commercially available treatment planning system (TPS). The software tool described in this work was developed to modify the TPS PDIP model by incorporating correction factors into the predicted EPID image to account for the difference in EPID response to open beam radiation and multileaf collimator (MLC) transmitted radiation. The processes performed by the software tool include; i) read the MLC file and the PDIP from the TPS, ii) calculate the fraction of beam-on time that each point in the IMRT beam is shielded by MLC leaves, iii) interpolate correction factors from look-up tables, iv) create a corrected PDIP image from the product of the original PDIP and the correction factors and write the corrected image to file, v) display, analyse, and export various image datasets. The software tool was developed using the Microsoft Visual Studio.NET framework with the C# compiler. The operation of the software tool was validated. This software provided useful tools for EPID dosimetry research, and it is being utilised and further developed in ongoing EPID dosimetry and IMRT dosimetry projects. PMID:18946980

  12. Hanford Internal Dosimetry Project manual. Revision 1

    SciTech Connect

    Carbaugh, E.H.; Bihl, D.E.; MacLellan, J.A.; Long, M.P.

    1994-07-01

    This document describes the Hanford Internal Dosimetry Project, as it is administered by Pacific Northwest Laboratory (PNL) in support of the US Department of Energy and its Hanford contractors. Project services include administrating the bioassay monitoring program, evaluating and documenting assessment of potential intakes and internal dose, ensuring that analytical laboratories conform to requirements, selecting and applying appropriate models and procedures for evaluating radionuclide deposition and the resulting dose, and technically guiding and supporting Hanford contractors in matters regarding internal dosimetry. Specific chapters deal with the following subjects: practices of the project, including interpretation of applicable DOE Orders, regulations, and guidance into criteria for assessment, documentation, and reporting of doses; assessment of internal dose, including summary explanations of when and how assessments are performed; recording and reporting practices for internal dose; selection of workers for bioassay monitoring and establishment of type and frequency of bioassay measurements; capability and scheduling of bioassay monitoring services; recommended dosimetry response to potential internal exposure incidents; quality control and quality assurance provisions of the program.

  13. Radiation dosimetry and spectrometry with superheated emulsions

    NASA Astrophysics Data System (ADS)

    d'Errico, Francesco

    2001-09-01

    Detectors based on emulsions of overexpanded halocarbon droplets in tissue equivalent aqueous gels or soft polymers, known as "superheated drop detectors" or "bubble (damage) detectors", have been used in radiation detection, dosimetry and spectrometry for over two decades. Recent technological advances have led to the introduction of several instruments for individual and area monitoring: passive integrating meters based on the optical or volumetric registration of the bubbles, and active counters detecting bubble nucleations acoustically. These advances in the instrumentation have been matched by the progress made in the production of stable and well-specified emulsions of superheated droplets. A variety of halocarbons are employed in the formulation of the detectors, and this permits a wide range of applications. In particular, halocarbons with a moderate degree of superheat, i.e. a relatively small difference between their operating temperature and boiling point, can be used in neutron dosimetry and spectrometry since they are only nucleated by energetic heavy ions such as those produced by fast neutrons. More recently, halocarbons with an elevated degree of superheat have been utilised to produce emulsions that nucleate with much smaller energy deposition and detect low linear energy transfer radiations, such as photons and electrons. This paper reviews the detector physics of superheated emulsions and their applications in radiation measurements, particularly in neutron dosimetry and spectrometry.

  14. Effects of temperature variation on MOSFET dosimetry.

    PubMed

    Cheung, Tsang; Butson, Martin J; Yu, Peter K N

    2004-07-01

    This note investigates temperature effects on dosimetry using a metal oxide semiconductor field effect transistor (MOSFET) for radiotherapy x-ray treatment. This was performed by analysing the dose response and threshold voltage outputs for MOSFET dosimeters as a function of ambient temperature. Results have shown that the clinical semiconductor dosimetry system (CSDS) MOSFET provides stable dose measurements with temperatures varying from 15 degrees C up to 40 degrees C. Thus standard irradiations performed at room temperature can be directly compared to in vivo dose assessments performed at near body temperature without a temperature correction function. The MOSFET dosimeter threshold voltage varies with temperature and this level is dependent on the dose history of the MOSFET dosimeter. However, the variation can be accounted for in the measurement method. For accurate dosimetry, the detector should be placed for approximately 60 s on a patient to allow thermal equilibrium before measurements are taken with the final reading performed whilst still attached to the patient or conversely left for approximately 120 s after removal from the patient if initial readout was measured at room temperature to allow temperature equilibrium to be established. PMID:15285264

  15. In vivo dosimetry in external beam radiotherapy

    SciTech Connect

    Mijnheer, Ben; Beddar, Sam; Izewska, Joanna; Reft, Chester

    2013-07-15

    In vivo dosimetry (IVD) is in use in external beam radiotherapy (EBRT) to detect major errors, to assess clinically relevant differences between planned and delivered dose, to record dose received by individual patients, and to fulfill legal requirements. After discussing briefly the main characteristics of the most commonly applied IVD systems, the clinical experience of IVD during EBRT will be summarized. Advancement of the traditional aspects of in vivo dosimetry as well as the development of currently available and newly emerging noninterventional technologies are required for large-scale implementation of IVD in EBRT. These new technologies include the development of electronic portal imaging devices for 2D and 3D patient dosimetry during advanced treatment techniques, such as IMRT and VMAT, and the use of IVD in proton and ion radiotherapy by measuring the decay of radiation-induced radionuclides. In the final analysis, we will show in this Vision 20/20 paper that in addition to regulatory compliance and reimbursement issues, the rationale for in vivo measurements is to provide an accurate and independent verification of the overall treatment procedure. It will enable the identification of potential errors in dose calculation, data transfer, dose delivery, patient setup, and changes in patient anatomy. It is the authors' opinion that all treatments with curative intent should be verified through in vivo dose measurements in combination with pretreatment checks.

  16. Reconstructive dosimetry for cutaneous radiation syndrome

    PubMed Central

    Lima, C.M.A.; Lima, A.R.; Degenhardt, Ä.L.; Valverde, N.J.; Da Silva, F.C.A.

    2015-01-01

    According to the International Atomic Energy Agency (IAEA), a relatively significant number of radiological accidents have occurred in recent years mainly because of the practices referred to as potentially high-risk activities, such as radiotherapy, large irradiators and industrial radiography, especially in gammagraphy assays. In some instances, severe injuries have occurred in exposed persons due to high radiation doses. In industrial radiography, 80 cases involving a total of 120 radiation workers, 110 members of the public including 12 deaths have been recorded up to 2014. Radiological accidents in industrial practices in Brazil have mainly resulted in development of cutaneous radiation syndrome (CRS) in hands and fingers. Brazilian data include 5 serious cases related to industrial gammagraphy, affecting 7 radiation workers and 19 members of the public; however, none of them were fatal. Some methods of reconstructive dosimetry have been used to estimate the radiation dose to assist in prescribing medical treatment. The type and development of cutaneous manifestations in the exposed areas of a person is the first achievable gross dose estimation. This review article presents the state-of-the-art reconstructive dosimetry methods enabling estimation of local radiation doses and provides guidelines for medical handling of the exposed individuals. The review also presents the Chilean and Brazilian radiological accident cases to highlight the importance of reconstructive dosimetry. PMID:26445332

  17. Adiponectin Promotes Human Jaw Bone Marrow Stem Cell Osteogenesis.

    PubMed

    Pu, Y; Wu, H; Lu, S; Hu, H; Li, D; Wu, Y; Tang, Z

    2016-07-01

    Human jaw bone marrow mesenchymal stem cells (h-JBMMSCs) are multipotent progenitor cells with osteogenic differentiation potential. The relationship between adiponectin (APN) and the metabolism of h-JBMMSCs has not been fully elucidated, and the underlying mechanism remains unclear. The aim of the study was to investigate the effect and mechanism of APN on h-JBMMSC metabolism. h-JBMMSCs were obtained from the primary culture of human jaw bones and treated with or without APN (1 µg/mL). Osteogenesis-related gene expression was evaluated by real-time polymerase chain reaction (PCR), alkaline phosphatase (ALP) activity assay, and enzyme-linked immunosorbent assay (ELISA). To further investigate the signaling pathway, mechanistic studies were performed using Western blotting, immunofluorescence, lentiviral transduction, and SB202190 (a specific p38 inhibitor). Alizarin Red staining showed that APN promoted h-JBMMSC osteogenesis. Real-time PCR, ALP assay, and ELISA showed that ALP, osteocalcin (OCN), osteopontin, and integrin-binding sialoprotein were up-regulated in APN-treated cells compared to untreated controls. Immunofluorescence revealed that adaptor protein containing a pleckstrin homology domain, phosphotyrosine domain, and leucine zipper motif (APPL1) translocated from the nucleus to the cytoplasm with APN treatment. Additionally, the phosphorylation of p38 mitogen-activated protein kinase (MAPK) increased over time with APN treatment. Moreover, knockdown of APPL1 or p38 MAPK inhibition blocked the expression of APN-induced calcification-related genes including ALP, Runt-related transcription factor 2 (RUNX2), and OCN. Furthermore, Alizarin Red staining of calcium nodes was not increased by the knockdown of APPL1 or p38 inhibition. Our data suggest that this regulation is mediated through the APPL1-p38 MAPK signaling pathway. These findings collectively provide evidence that APN induces the osteogenesis of h-JBMMSCs through APPL1-mediated p38 MAPK activation

  18. Evaluation of radiochromic gel dosimetry and polymer gel dosimetry in a clinical dose verification

    NASA Astrophysics Data System (ADS)

    Vandecasteele, Jan; De Deene, Yves

    2013-09-01

    A quantitative comparison of two full three-dimensional (3D) gel dosimetry techniques was assessed in a clinical setting: radiochromic gel dosimetry with an in-house developed optical laser CT scanner and polymer gel dosimetry with magnetic resonance imaging (MRI). To benchmark both gel dosimeters, they were exposed to a 6 MV photon beam and the depth dose was compared against a diamond detector measurement that served as golden standard. Both gel dosimeters were found accurate within 4% accuracy. In the 3D dose matrix of the radiochromic gel, hotspot dose deviations up to 8% were observed which are attributed to the fabrication procedure. The polymer gel readout was shown to be sensitive to B0 field and B1 field non-uniformities as well as temperature variations during scanning. The performance of the two gel dosimeters was also evaluated for a brain tumour IMRT treatment. Both gel measured dose distributions were compared against treatment planning system predicted dose maps which were validated independently with ion chamber measurements and portal dosimetry. In the radiochromic gel measurement, two sources of deviations could be identified. Firstly, the dose in a cluster of voxels near the edge of the phantom deviated from the planned dose. Secondly, the presence of dose hotspots in the order of 10% related to inhomogeneities in the gel limit the clinical acceptance of this dosimetry technique. Based on the results of the micelle gel dosimeter prototype presented here, chemical optimization will be subject of future work. Polymer gel dosimetry is capable of measuring the absolute dose in the whole 3D volume within 5% accuracy. A temperature stabilization technique is incorporated to increase the accuracy during short measurements, however keeping the temperature stable during long measurement times in both calibration phantoms and the volumetric phantom is more challenging. The sensitivity of MRI readout to minimal temperature fluctuations is demonstrated which

  19. Red Clover Breeding Progress

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Red clover (Trifolium pratense L.) is an important forage legume grown on approximately 4 million hectares worldwide. It has a long and varied history in agriculture. Active breeding efforts began at the end of the 19th century. Since this time significant improvement in red clover cultivar for a...

  20. Cobb's Red Cabbage Indicator.

    ERIC Educational Resources Information Center

    Cobb, Vicki

    1998-01-01

    Describes the use of an indicator made from the pigment in red cabbage. Cabbage is grated then soaked in water. When the water is a strong red, the cabbage is strained out. The cabbage-juice indicator is then used to test for acids and bases. Includes a list of good foods to test for acidity and alkalinity. (PVD)

  1. Facilitation of allogeneic bone marrow transplantation by a T cell-specific immunotoxin containing daunomycin

    SciTech Connect

    Xie, S.S.; Inazawa, M.; Sinha, N.; Sawada, S.; Vergidis, R.; Diener, E.

    1987-12-01

    Daunomycin coupled via an acid-sensitive spacer to monoclonal Thy-1.2-specific antibody was used to purge T lymphocytes from a 1:1 mixture of murine C57BL/6J bone marrow and spleen cells prior to engraftment in fully allogeneic, irradiated BALB/c recipients. Treatment of bone marrow with the immunotoxin at a concentration used for purging had no effect on the viability of committed hematopoietic progenitor or multipotent stem cells. All of the recipients of purged bone marrow were at least 80% chimeric for donor peripheral blood cells and none developed graft-versus-host disease. Out of 50 chimeras, 49 were still alive more than 200 days posttransplantation. The chimeras were shown to be tolerant to donor tissue as tested by mixed lymphocyte reactivity, cell-mediated cytotoxicity, and skin grafting. The same tests revealed full immunocompetence of chimeras to third-party alloantigens. In vivo IgM and IgG antibody responses to sheep red blood cells were similar in magnitude in allogeneically and syngeneically reconstituted mice.

  2. Application of ferrokinetic investigation for differential diagnosis in bone marrow hypoplasia and their clinical relevance.

    PubMed

    Gupta, M; Roth, P; Werner, E; Kaltwasser, J P

    1979-02-01

    In this study, erythropoietic activity of bone marrow has been evaluated by ferrokinetics. For that purpose, the data of radioiron disappearance from plasma and its ultimate incorporation in red blood cells after the injection of about 10 muCi of 59Fe tagged autologous plasma, were analysed and fitted to the sum of three exponentials, using a non-linear least square SAAM-25 program on UNIVAC-1108 computer. A function representing time-activity relationship, was constructed. The functional physiological model of iron metabolism, proposed by Cavill and Ricketts, was used to calculate various ferrokinetic parameters in terms of coefficients and exponents of the time-activity function. After identifying the parameters that could be used as indices of erythropoietic activity of bone marrow, the study was repeated in six patients after they had undergone myelostimulative therapy. A distinct correlation was found between ferrokinetic observations and clinical and biochemical findings. It has been demonstrated that in histologically diagnosed cases with bone marrow hypoplasia, a further differentiation between pure aplasia and those with hypoplasia together with ineffective erythropoiesis was possible. This discrimination which is clinically very important, is only possible by means of kinetic investigations. PMID:499222

  3. Jupiter's Great Red spot

    NASA Technical Reports Server (NTRS)

    1979-01-01

    This color composite made from Voyager 2 narrow-angle camera frames shows the Great Red Spot during the late Jovian afternoon. North of the Red Spot lies a curious darker section of the South Equatorial Belt (SEB), the belt in which the Red Spot is located. A bright eruption of material passing from the SEB northward into the diffuse equatorial clouds has been observed on all occasions when this feature passes north of the Red Spot. The remnants of one such eruption are apparent in this photograph. To the lower left of the Red Spot lies one of the three long-lived White Ovals. This photograph was taken on June 29, 1979, when Voyager 2 was over 9 million kilometers (nearly 6 million miles) from Jupiter. The smallest features visible are over 170 kilometers (106 miles) across.

  4. Dosimetry tools and techniques for IMRT

    SciTech Connect

    Low, Daniel A.; Moran, Jean M.; Dempsey, James F.; Dong Lei; Oldham, Mark

    2011-03-15

    Intensity modulated radiation therapy (IMRT) poses a number of challenges for properly measuring commissioning data and quality assurance (QA) radiation dose distributions. This report provides a comprehensive overview of how dosimeters, phantoms, and dose distribution analysis techniques should be used to support the commissioning and quality assurance requirements of an IMRT program. The proper applications of each dosimeter are described along with the limitations of each system. Point detectors, arrays, film, and electronic portal imagers are discussed with respect to their proper use, along with potential applications of 3D dosimetry. Regardless of the IMRT technique utilized, some situations require the use of multiple detectors for the acquisition of accurate commissioning data. The overall goal of this task group report is to provide a document that aids the physicist in the proper selection and use of the dosimetry tools available for IMRT QA and to provide a resource for physicists that describes dosimetry measurement techniques for purposes of IMRT commissioning and measurement-based characterization or verification of IMRT treatment plans. This report is not intended to provide a comprehensive review of commissioning and QA procedures for IMRT. Instead, this report focuses on the aspects of metrology, particularly the practical aspects of measurements that are unique to IMRT. The metrology of IMRT concerns the application of measurement instruments and their suitability, calibration, and quality control of measurements. Each of the dosimetry measurement tools has limitations that need to be considered when incorporating them into a commissioning process or a comprehensive QA program. For example, routine quality assurance procedures require the use of robust field dosimetry systems. These often exhibit limitations with respect to spatial resolution or energy response and need to themselves be commissioned against more established dosimeters. A chain of

  5. Dosimetry tools and techniques for IMRT.

    PubMed

    Low, Daniel A; Moran, Jean M; Dempsey, James F; Dong, Lei; Oldham, Mark

    2011-03-01

    Intensity modulated radiation therapy (IMRT) poses a number of challenges for properly measuring commissioning data and quality assurance (QA) radiation dose distributions. This report provides a comprehensive overview of how dosimeters, phantoms, and dose distribution analysis techniques should be used to support the commissioning and quality assurance requirements of an IMRT program. The proper applications of each dosimeter are described along with the limitations of each system. Point detectors, arrays, film, and electronic portal imagers are discussed with respect to their proper use, along with potential applications of 3D dosimetry. Regardless of the IMRT technique utilized, some situations require the use of multiple detectors for the acquisition of accurate commissioning data. The overall goal of this task group report is to provide a document that aids the physicist in the proper selection and use of the dosimetry tools available for IMRT QA and to provide a resource for physicists that describes dosimetry measurement techniques for purposes of IMRT commissioning and measurement-based characterization or verification of IMRT treatment plans. This report is not intended to provide a comprehensive review of commissioning and QA procedures for IMRT. Instead, this report focuses on the aspects of metrology, particularly the practical aspects of measurements that are unique to IMRT. The metrology of IMRT concerns the application of measurement instruments and their suitability, calibration, and quality control of measurements. Each of the dosimetry measurement tools has limitations that need to be considered when incorporating them into a commissioning process or a comprehensive QA program. For example, routine quality assurance procedures require the use of robust field dosimetry systems. These often exhibit limitations with respect to spatial resolution or energy response and need to themselves be commissioned against more established dosimeters. A chain of

  6. MR imaging of therapy-induced changes of bone marrow

    PubMed Central

    Henning, Tobias; Link, Thomas M.

    2006-01-01

    MR imaging of bone marrow infiltration by hematologic malignancies provides non-invasive assays of bone marrow cellularity and vascularity to supplement the information provided by bone marrow biopsies. This article will review the MR imaging findings of bone marrow infiltration by hematologic malignancies with special focus on treatment effects. MR imaging findings of the bone marrow after radiation therapy and chemotherapy will be described. In addition, changes in bone marrow microcirculation and metabolism after anti-angiogenesis treatment will be reviewed. Finally, new specific imaging techniques for the depiction of regulatory events that control blood vessel growth and cell proliferation will be discussed. Future developments are directed to yield comprehensive information about bone marrow structure, function and microenvironment. PMID:17021706

  7. Biology of Marrow Failure Syndromes: Role of Microenvironment and Niches

    PubMed Central

    Balderman, Sophia R.; Calvi, Laura M.

    2015-01-01

    The marrow microenvironment and its components regulate hematopoietic stem and progenitor cell (HSC) fate. An abnormality in the marrow microenvironment and specific dysfunction of the HSC niche could play a critical role in initiation, disease progression and response to therapy of marrow failure syndromes. Therefore, the identification of changes in the HSC niche in marrow failure syndromes should lead to further knowledge of the signals that disrupt the normal microenvironment. In turn, niche disruption may contribute to disease morbidity resulting in pancytopenia and clonal evolution, and its understanding could point to new therapeutic targets for these conditions. We briefly (a) review evidence for the importance of the marrow microenvironment as a regulator of normal hematopoiesis, (b) summarize the current knowledge regarding the role of dysfunctions in the marrow microenvironment in marrow failure syndromes, and (c) propose a strategy through which niche stimulation can complement current treatment for MDS. PMID:25696837

  8. Reactor Dosimetry State of the Art 2008

    NASA Astrophysics Data System (ADS)

    Voorbraak, Wim; Debarberis, Luigi; D'Hondt, Pierre; Wagemans, Jan

    2009-08-01

    Oral session 1: Retrospective dosimetry. Retrospective dosimetry of VVER 440 reactor pressure vessel at the 3rd unit of Dukovany NPP / M. Marek ... [et al.]. Retrospective dosimetry study at the RPV of NPP Greifswald unit 1 / J. Konheiser ... [et al.]. Test of prototype detector for retrospective neutron dosimetry of reactor internals and vessel / K. Hayashi ... [et al.]. Neutron doses to the concrete vessel and tendons of a magnox reactor using retrospective dosimetry / D. A. Allen ... [et al.]. A retrospective dosimetry feasibility study for Atucha I / J. Wagemans ... [et al.]. Retrospective reactor dosimetry with zirconium alloy samples in a PWR / L. R. Greenwood and J. P. Foster -- Oral session 2: Experimental techniques. Characterizing the Time-dependent components of reactor n/y environments / P. J. Griffin, S. M. Luker and A. J. Suo-Anttila. Measurements of the recoil-ion response of silicon carbide detectors to fast neutrons / F. H. Ruddy, J. G. Seidel and F. Franceschini. Measurement of the neutron spectrum of the HB-4 cold source at the high flux isotope reactor at Oak Ridge National Laboratory / J. L. Robertson and E. B. Iverson. Feasibility of cavity ring-down laser spectroscopy for dose rate monitoring on nuclear reactor / H. Tomita ... [et al.]. Measuring transistor damage factors in a non-stable defect environment / D. B. King ... [et al.]. Neutron-detection based monitoring of void effects in boiling water reactors / J. Loberg ... [et al.] -- Poster session 1: Power reactor surveillance, retrospective dosimetry, benchmarks and inter-comparisons, adjustment methods, experimental techniques, transport calculations. Improved diagnostics for analysis of a reactor pulse radiation environment / S. M. Luker ... [et al.]. Simulation of the response of silicon carbide fast neutron detectors / F. Franceschini, F. H. Ruddy and B. Petrović. NSV A-3: a computer code for least-squares adjustment of neutron spectra and measured dosimeter responses / J. G

  9. Magnetic resonance imaging of the spinal marrow: Basic understanding of the normal marrow pattern and its variant

    PubMed Central

    Nouh, Mohamed Ragab; Eid, Ahmed Fathi

    2015-01-01

    For now, magnetic resonance (MR) is the best noninvasive imaging modality to evaluate vertebral bone marrow thanks to its inherent soft-tissue contrast and non-ionizing nature. A daily challenging scenario for every radiologist interpreting MR of the vertebral column is discerning the diseased from normal marrow. This requires the radiologist to be acquainted with the used MR techniques to judge the spinal marrow as well as its normal MR variants. Conventional sequences used basically to image marrow include T1W, fat-suppressed T2W and short tau inversion recovery (STIR) imaging provides gross morphological data. Interestingly, using non-routine MR sequences; such as opposed phase, diffusion weighted, MR spectroscopy and contrasted-enhanced imaging; may elucidate the nature of bone marrow heterogeneities; by inferring cellular and chemical composition; and adding new functional prospects. Recalling the normal composition of bone marrow elements and the physiologic processes of spinal marrow conversion and reconversion eases basic understanding of spinal marrow imaging. Additionally, orientation with some common variants seen during spinal marrow MR imaging as hemangiomas and bone islands is a must. Moreover, awareness of the age-associated bone marrow changes as well as changes accompanying different variations of the subject’s health state is essential for radiologists to avoid overrating normal MR marrow patterns as pathologic states and metigate unnecessary further work-up. PMID:26753060

  10. Magnetic resonance imaging of the spinal marrow: Basic understanding of the normal marrow pattern and its variant.

    PubMed

    Nouh, Mohamed Ragab; Eid, Ahmed Fathi

    2015-12-28

    For now, magnetic resonance (MR) is the best noninvasive imaging modality to evaluate vertebral bone marrow thanks to its inherent soft-tissue contrast and non-ionizing nature. A daily challenging scenario for every radiologist interpreting MR of the vertebral column is discerning the diseased from normal marrow. This requires the radiologist to be acquainted with the used MR techniques to judge the spinal marrow as well as its normal MR variants. Conventional sequences used basically to image marrow include T1W, fat-suppressed T2W and short tau inversion recovery (STIR) imaging provides gross morphological data. Interestingly, using non-routine MR sequences; such as opposed phase, diffusion weighted, MR spectroscopy and contrasted-enhanced imaging; may elucidate the nature of bone marrow heterogeneities; by inferring cellular and chemical composition; and adding new functional prospects. Recalling the normal composition of bone marrow elements and the physiologic processes of spinal marrow conversion and reconversion eases basic understanding of spinal marrow imaging. Additionally, orientation with some common variants seen during spinal marrow MR imaging as hemangiomas and bone islands is a must. Moreover, awareness of the age-associated bone marrow changes as well as changes accompanying different variations of the subject's health state is essential for radiologists to avoid overrating normal MR marrow patterns as pathologic states and metigate unnecessary further work-up. PMID:26753060

  11. Pure red cell aplasia induced by epoetin zeta.

    PubMed

    Panichi, Vincenzo; Ricchiuti, Guido; Scatena, Alessia; Del Vecchio, Lucia; Locatelli, Francesco

    2016-08-01

    Pure red cell aplasia (PRCA) may develop in patients with chronic kidney disease receiving erythropoiesis-stimulating agents (ESA). We report on a 72-year-old patient who developed hypo-proliferative anaemia unresponsive to ESA following the administration of epoetin zeta subcutaneously for 7 months. On the basis of severe isolated hypoplasia of the erythroid line in the bone marrow and high-titre neutralizing anti-erythropoietin antibodies (Ab), a diagnosis of Ab-mediated PRCA was made. Epoetin zeta was discontinued and the patient was given steroids. This was associated with anaemia recovery. To our knowledge this is the first PRCA case related to epoetin zeta. PMID:27478604

  12. Pure red cell aplasia induced by epoetin zeta

    PubMed Central

    Panichi, Vincenzo; Ricchiuti, Guido; Scatena, Alessia; Del Vecchio, Lucia; Locatelli, Francesco

    2016-01-01

    Pure red cell aplasia (PRCA) may develop in patients with chronic kidney disease receiving erythropoiesis-stimulating agents (ESA). We report on a 72-year-old patient who developed hypo-proliferative anaemia unresponsive to ESA following the administration of epoetin zeta subcutaneously for 7 months. On the basis of severe isolated hypoplasia of the erythroid line in the bone marrow and high-titre neutralizing anti-erythropoietin antibodies (Ab), a diagnosis of Ab-mediated PRCA was made. Epoetin zeta was discontinued and the patient was given steroids. This was associated with anaemia recovery. To our knowledge this is the first PRCA case related to epoetin zeta. PMID:27478604

  13. The effect of autologous bone marrow stromal cells differentiated on scaffolds for canine tibial bone reconstruction.

    PubMed

    Özdal-Kurt, F; Tuğlu, I; Vatansever, H S; Tong, S; Deliloğlu-Gürhan, S I

    2015-01-01

    Bone marrow contains mesenchymal stem cells that form many tissues. Various scaffolds are available for bone reconstruction by tissue engineering. Osteoblastic differentiated bone marrow stromal cells (BMSC) promote osteogenesis on scaffolds and stimulate bone regeneration. We investigated the use of cultured autologous BMSC on different scaffolds for healing defects in tibias of adult male canines. BMSC were isolated from canine humerus bone marrow, differentiated into osteoblasts in culture and loaded onto porous ceramic scaffolds including hydroxyapatite 1, hydroxyapatite gel and calcium phosphate. Osteoblast differentiation was verified by osteonectine and osteocalcine immunocytochemistry. The scaffolds with stromal cells were implanted in the tibial defect. Scaffolds without stromal cells were used as controls. Sections from the defects were processed for histological, ultrastructural, immunohistochemical and histomorphometric analyses to analyze the healing of the defects. BMSC were spread, allowed to proliferate and differentiate to osteoblasts as shown by alizarin red histochemistry, and osteocalcine and osteonectine immunostaining. Scanning electron microscopy showed that BMSC on the scaffolds were more active and adhesive to the calcium phosphate scaffold compared to the others. Macroscopic bone formation was observed in all groups, but scaffolds with stromal cells produced significantly better results. Bone healing occurred earlier and faster with stromal cells on the calcium phosphate scaffold and produced more callus compared to other scaffolds. Tissue healing and osteoblastic marker expression also were better with stromal cells on the scaffolds. Increased trabecula formation, cell density and decreased fibrosis were observed in the calcium phosphate scaffold with stromal cells. Autologous cultured stromal cells on the scaffolds were useful for healing of canine tibial bone defects. The calcium phosphate scaffold was the best for both cell

  14. Automatic in vivo portal dosimetry of all treatments

    NASA Astrophysics Data System (ADS)

    Olaciregui-Ruiz, I.; Rozendaal, R.; Mijnheer, B.; van Herk, M.; Mans, A.

    2013-11-01

    At our institution EPID (electronic portal imaging device) dosimetry is routinely applied to perform in vivo dose verification of all patient treatments with curative intent since January 2008. The major impediment of the method has been the amount of work required to produce and inspect the in vivo dosimetry reports (a time-consuming and labor-intensive process). In this paper we present an overview of the actions performed to implement an automated in vivo dosimetry solution clinically. We reimplemented the EPID dosimetry software and modified the acquisition software. Furthermore, we introduced new tools to periodically inspect the record-and-verify database and automatically run the EPID dosimetry software when needed. In 2012, 95% of our 3839 treatments scheduled for in vivo dosimetry were analyzed automatically (27 633 portal images of intensity-modulated radiotherapy (IMRT) fields, 5551 portal image data of VMAT arcs, and 2003 portal images of non-IMRT fields). The in vivo dosimetry verification results are available a few minutes after delivery and alerts are immediately raised when deviations outside tolerance levels are detected. After the clinical introduction of this automated solution, inspection of the detected deviations is the only remaining work. These newly developed tools are a major step forward towards full integration of in vivo EPID dosimetry in radiation oncology practice.

  15. 10 CFR 835.1304 - Nuclear accident dosimetry.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 4 2012-01-01 2012-01-01 false Nuclear accident dosimetry. 835.1304 Section 835.1304 Energy DEPARTMENT OF ENERGY OCCUPATIONAL RADIATION PROTECTION Emergency Exposure Situations § 835.1304 Nuclear accident dosimetry. (a) Installations possessing sufficient quantities of fissile material...

  16. Neutron dosimetry and radiation damage calculations for HFBR

    SciTech Connect

    Greenwood, L.R.; Ratner, R.T.

    1998-03-01

    Neutron dosimetry measurements have been conducted for various positions of the High Flux Beam Reactor (HFBR) at Brookhaven National Laboratory (BNL) in order to measure the neutron flux and energy spectra. Neutron dosimetry results and radiation damage calculations are presented for positions V10, V14, and V15.

  17. 10 CFR 835.1304 - Nuclear accident dosimetry.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 4 2013-01-01 2013-01-01 false Nuclear accident dosimetry. 835.1304 Section 835.1304 Energy DEPARTMENT OF ENERGY OCCUPATIONAL RADIATION PROTECTION Emergency Exposure Situations § 835.1304 Nuclear accident dosimetry. (a) Installations possessing sufficient quantities of fissile material...

  18. 10 CFR 835.1304 - Nuclear accident dosimetry.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 4 2014-01-01 2014-01-01 false Nuclear accident dosimetry. 835.1304 Section 835.1304 Energy DEPARTMENT OF ENERGY OCCUPATIONAL RADIATION PROTECTION Emergency Exposure Situations § 835.1304 Nuclear accident dosimetry. (a) Installations possessing sufficient quantities of fissile material...

  19. Student Perceptions of an Online Medical Dosimetry Program

    ERIC Educational Resources Information Center

    Lenards, Nishele D.

    2007-01-01

    The University of Wisconsin--La Crosse offers the first web-based medical dosimetry program in the nation. There is no data to research a program of this type. This research consisted of the evaluation of other distance education programs including health profession programs in addition to face-to-face medical dosimetry programs. There was need to…

  20. Automatic in vivo portal dosimetry of all treatments.

    PubMed

    Olaciregui-Ruiz, I; Rozendaal, R; Mijnheer, B; van Herk, M; Mans, A

    2013-11-21

    At our institution EPID (electronic portal imaging device) dosimetry is routinely applied to perform in vivo dose verification of all patient treatments with curative intent since January 2008. The major impediment of the method has been the amount of work required to produce and inspect the in vivo dosimetry reports (a time-consuming and labor-intensive process). In this paper we present an overview of the actions performed to implement an automated in vivo dosimetry solution clinically. We reimplemented the EPID dosimetry software and modified the acquisition software. Furthermore, we introduced new tools to periodically inspect the record-and-verify database and automatically run the EPID dosimetry software when needed. In 2012, 95% of our 3839 treatments scheduled for in vivo dosimetry were analyzed automatically (27,633 portal images of intensity-modulated radiotherapy (IMRT) fields, 5551 portal image data of VMAT arcs, and 2003 portal images of non-IMRT fields). The in vivo dosimetry verification results are available a few minutes after delivery and alerts are immediately raised when deviations outside tolerance levels are detected. After the clinical introduction of this automated solution, inspection of the detected deviations is the only remaining work. These newly developed tools are a major step forward towards full integration of in vivo EPID dosimetry in radiation oncology practice. PMID:24201085

  1. Post-bone marrow transplant patient management.

    PubMed Central

    Poliquin, C. M.

    1990-01-01

    Increasingly, bone marrow transplant (BMT) is the treatment of choice for certain hematologic diseases. BMT is, however, a risky procedure with many potentially serious complications. Some complications are the result of the conditioning regimen, a stage of transplantation that includes large doses of chemotherapy and/or radiation therapy. Conditioning-induced neutropenia and thrombocytopenia often result in infection, bleeding, and mucositis. Veno-occlusive disease (VOD), a chemotherapy-induced hepatotoxicity, can cause a mild to severe form of liver disease. Other complications are directly attributable to the engrafted new marrow. Graft-versus-host disease, a rejection process initiated by immunocompetent donor T lymphocytes, is a complication frequently observed in allogeneic BMT. Approximately 14-28 days after the day of transplant, signs of engraftment begin to appear. When specific discharge criteria are met, the BMT patient is discharged from the hospital. Specific follow-up medical care is ongoing for about one year after BMT. PMID:2293508

  2. Dosimetry and toxicity of Samarium-153-EDTMP administered for bone pain due to skeletal metastases

    SciTech Connect

    Bayouth, J.E.; Macey, D.J.; Kasi, L.P.

    1994-01-01

    Palliation of bone pain in patients with cancer metastatic to bone is being evaluated in several cancer centers by the administration of the bone-seeking phosphonate ethylenediaminetetramethylenephosphonic acid (EDTMP) chelated with the beta particle-emitting radionuclide {sup 153}Sm. In this study {sup 153}Sm-EDTMP was intravenously injected into 19 patients over a 1-min period. Patients received up to four injections of 18.5 MBq (0.5 mCi) or 37 MBq (1.0mCi) per kilogram of body weight. Skeletal retention was calculated from urinary excretion. No uptake of {sup 153}Sm-EDTMP in nonskeletal tissues was observed in whole-body gamma camera images. The mean skeletal uptake for all patients was 54% {plus_minus} 16% of the injected dose (%ID). This resulted in the bone marrow receiving 89 cGy/GBq {plus_minus} 27 cGy/GBq (3.28 cGy/mCi {plus_minus} 0.99 cGy/mCi), with calculated marrow doses ranging from 27 cGy to 338 cGy. For each patient, the estimated radiation absorbed dose to the marrow was correlated to the percent decrease in platelet number, ranging from 7.4% to 78.9%. Since the deviation of uptake between the four injections for a given patient (7.6% ID) was less than the deviation for all patients (16% ID), the initial dose may be used to estimate the skeletal uptake for the remaining doses. These radiation dose estimates permit patients at risk to be identified prior to reaching myelotoxicity and develop dose-response models. Thirteen patients (68%) reported significant pain relief from this radionuclide therapy. Bone pain appears to be alleviated by {sup 153}Sm-EDTMP with limited red marrow doses and no toxic effects in other organs. 15 refs., 8 figs., 2 figs.

  3. [Allogenic bone marrow transplantation complications. Part II].

    PubMed

    Saloua, L; Tarek, B O; Abderrahman, A; Abdeladhim, B A

    2000-03-01

    Bone marrow transplantation increase the chances of cure of many hematology and also neoplasms cancers. The procedure is however a cause of expected mortality and morbidity. The complications are represented by mucocutaneous, toxicity graft versus host disease, veno-occlusive disease and most importantly injections consequences all this complications needs to be prevented and treated considering the risk associated to the moderling immunosuppression. PMID:11026816

  4. Total body irradiation in bone marrow transplantation: the influence of fractionation and delay of marrow infusion

    SciTech Connect

    Lichter, A.S.; Tracy, D.; Lam, W.C.; Order, S.E.

    1980-03-01

    Bone marrow transplantation (BMT) after total body irradiation (TBI) and cyclophosphamide is being employed increasingly in the therapy of end stage leukemia. Interstitial pneumonitis (IP) represents a major acute toxicity after allogeneic transplantation. A more rapid reconstitution of lymphoid organs and bone marrow post transplant may result in increased immune competence and hence fewer opportunistic pulmonary infections and IP. By delaying the infusion of marrow to 72 hr after TBI (1250 rad at 7.5 rad/min) instead of the customary 24 hr, we can demonstrate an increase in initial repopulation of thymus, spleen and bone marrow, with syngeneic transplants in Lewis rats. Interstitial pneumonitis may also be caused, in part, by the pulmonary toxicity of large single exposures of TBI. Clinical and laboratory data suggest that fractionated TBI may be less toxic to the lung. When fractionated TBI (625 rad x 2, 7.5 rad/min) is compared to single dose TBI (1250 rad, 7.5 rad/min), and increased initial repopulation of lymphoid organs is observed when fractionated therapy is employed. Delay in marrow infusion and fractionation of TBI exposure may have clinical advantages in patients who receive BMT.

  5. EURADOS strategic research agenda: vision for dosimetry of ionising radiation.

    PubMed

    Rühm, W; Fantuzzi, E; Harrison, R; Schuhmacher, H; Vanhavere, F; Alves, J; Bottollier Depois, J F; Fattibene, P; Knežević, Ž; Lopez, M A; Mayer, S; Miljanić, S; Neumaier, S; Olko, P; Stadtmann, H; Tanner, R; Woda, C

    2016-02-01

    Since autumn 2012, the European Radiation Dosimetry Group (EURADOS) has been developing its Strategic Research Agenda (SRA), which is intended to contribute to the identification of future research needs in radiation dosimetry in Europe. The present article summarises-based on input from EURADOS Working Groups (WGs) and Voting Members-five visions in dosimetry and defines key issues in dosimetry research that are considered important for the next decades. The five visions include scientific developments required towards (a) updated fundamental dose concepts and quantities, (b) improved radiation risk estimates deduced from epidemiological cohorts, (c) efficient dose assessment for radiological emergencies, (d) integrated personalised dosimetry in medical applications and (e) improved radiation protection of workers and the public. The SRA of EURADOS will be used as a guideline for future activities of the EURADOS WGs. A detailed version of the SRA can be downloaded as a EURADOS report from the EURADOS website (www.eurados.org). PMID:25752758

  6. Knee cartilage defect: marrow stimulating techniques.

    PubMed

    Mirza, M Zain; Swenson, Richard D; Lynch, Scott A

    2015-12-01

    Painful chondral defects of the knee are very difficult problems. The incidence of these lesions in the general population is not known since there is likely a high rate of asymptomatic lesions. The rate of lesions found during arthroscopic exam is highly variable, with reports ranging from 11 to 72 % Aroen (Aroen Am J Sports Med 32: 211-5, 2004); Curl(Arthroscopy13: 456-60, 1997); Figueroa(Arthroscopy 23(3):312-5, 2007;); Hjelle(Arthroscopy 18: 730-4, 2002). Examples of current attempts at cartilage restoration include marrow stimulating techniques, ostochondral autografts, osteochondral allografts, and autologous chondrocyte transplantation. Current research in marrow stimulating techniques has been focused on enhancing and guiding the biology of microfracture and other traditional techniques. Modern advances in stem cell biology and biotechnology have provided many avenues for exploration. The purpose of this work is to review current techniques in marrow stimulating techniques as it relates to chondral damage of the knee. PMID:26411978

  7. Liver disease after bone marrow transplantation.

    PubMed Central

    Farthing, M J; Clark, M L; Sloane, J P; Powles, R L; McElwain, T J

    1982-01-01

    Liver dysfunction occurs after bone marrow transplantation but the relative importance of graft versus host disease and other factors, such as infection, radiation, and drugs, has not been clearly established. We have studied liver status before and after bone marrow transplantation in 43 consecutive patients and have related this to survival and factors that are recognised to cause liver injury. Minor abnormalities of liver tests occurred in 21% of patients before grafting but this did not influence survival or the development of liver disease after transplantation. During the first 50 days after grafting, 83% of patients had abnormal liver tests which were more severe in patients who subsequently died. Alanine transaminase was significantly higher in non-survivors and appeared to predict survival early after transplantation. Only non-survivors developed clinical signs of liver disease. Severe liver disease was always associated with graft versus host disease and atypia of the small bile ducts was the most useful histological marker of hepatic involvement with this disease. Two of the patients with hepatic graft versus host disease also has hepatic veno-occlusive disease and three fatalities had opportunistic infection of the liver, although, in the latter, death was not due primarily to liver dysfunction. Previous hepatitis and androgen therapy could not be implicated as important causes of hepatic damage but chemotherapy for acute leukaemia and conditioning regimens for bone marrow transplantation appear to be the most important factors in the development of hepatic veno-occlusive disease. Images Fig. 3 Fig. 4 PMID:7042484

  8. Red Bull Stratos Presentation

    NASA Video Gallery

    Red Bull Stratos High Performance Director Andy Walshe & Technical Project Director Art Thompson share the Stratos story with JSC. Supported by a team of experts, Felix Baumgartner reached 128,100 ...

  9. Jupiter's Great Red Spot

    NASA Technical Reports Server (NTRS)

    1996-01-01

    This view of Jupiter's Great Red Spot is a mosaic of two images taken by the Galileo spacecraft. The image was created using two filters, violet and near-infrared, at each of two camera positions. The Great Red Spot is a storm in Jupiter's atmosphere and is at least 300 years-old. Winds blow counterclockwise around the Great Red Spot at about 400 kilometers per hour (250 miles per hour). The size of the storm is more than one Earth diameter (13,000 kilometers or 8,000 miles) in the north-south direction and more than two Earth diameters in the east-west direction. In this oblique view, where the Great Red Spot is shown on the planet's limb, it appears longer in the north-south direction. The image was taken on June 26, 1996.

    The Galileo mission is managed by NASA's Jet Propulsion Laboratory.

  10. Red blood cell production

    MedlinePlus Videos and Cool Tools

    ... or another. Red blood cells are an important element of blood. Their job is to transport oxygen ... hemocytoblasts give rise to all of the formed elements in blood. If a hemocytoblast commits to becoming ...

  11. Build-up material requirements in clinical dosimetry during total body irradiation treatments

    PubMed Central

    Butson, Martin; Pope, Dane; Haque, Mamoon; Chen, Tom; Song, Guangli; Whitaker, May

    2016-01-01

    Total body irradiation (TBI) treatments are mainly used in a preparative regimen for hematopoietic stem cell (or bone marrow) transplantation. Our standard clinical regimen is a 12 Gy/6 fraction bi-daily technique using 6MV X-rays at a large extended source to surface distance (SSD). This work investigates and quantifies the dose build-up characteristics and thus the requirements for bolus used for in vivo dosimetry for TBI applications. Percentage dose build-up characteristics of photon beams have been investigated at large extended SSDs using ionization chambers and Gafchromic film. Open field measurements at different field sizes and with differing scatter conditions such as the introduction of standard Perspex scattering plates at different distances to the measurement point were made in an effort to determine the required bolus/build-up material required for accurate determination of applied dose. Percentage surface dose values measured for open fields at 300 cm SSD were found to range from 20% up to 65.5% for fields 5 cm × 5 cm to 40 cm × 40 cm, respectively. With the introduction of 1 cm Perspex scattering plates used in TBI treatments, the surface dose values increased up to 83–90% (93–97% at 1 mm depth), depending on the position of the Perspex scattering plate compared to the measurement point. Our work showed that at least 5 mm water equivalent bolus/scatter material should be placed over the EBT3 film for accurate dose assessment for TBI treatments. Results also show that a small but measurable decrease in measured dose occurred with 5 mm water equivalent thick bolus material of areas '3 cm2. As such, we recommend that 3 cm × 3 cm × 5 mm bolus build-up is the smallest size that should be placed over EBT3 Gafchromic film when used for accurate in vivo dosimetry for TBI applications. PMID:27217628

  12. Build-up material requirements in clinical dosimetry during total body irradiation treatments.

    PubMed

    Butson, Martin; Pope, Dane; Haque, Mamoon; Chen, Tom; Song, Guangli; Whitaker, May

    2016-01-01

    Total body irradiation (TBI) treatments are mainly used in a preparative regimen for hematopoietic stem cell (or bone marrow) transplantation. Our standard clinical regimen is a 12 Gy/6 fraction bi-daily technique using 6MV X-rays at a large extended source to surface distance (SSD). This work investigates and quantifies the dose build-up characteristics and thus the requirements for bolus used for in vivo dosimetry for TBI applications. Percentage dose build-up characteristics of photon beams have been investigated at large extended SSDs using ionization chambers and Gafchromic film. Open field measurements at different field sizes and with differing scatter conditions such as the introduction of standard Perspex scattering plates at different distances to the measurement point were made in an effort to determine the required bolus/build-up material required for accurate determination of applied dose. Percentage surface dose values measured for open fields at 300 cm SSD were found to range from 20% up to 65.5% for fields 5 cm × 5 cm to 40 cm × 40 cm, respectively. With the introduction of 1 cm Perspex scattering plates used in TBI treatments, the surface dose values increased up to 83-90% (93-97% at 1 mm depth), depending on the position of the Perspex scattering plate compared to the measurement point. Our work showed that at least 5 mm water equivalent bolus/scatter material should be placed over the EBT3 film for accurate dose assessment for TBI treatments. Results also show that a small but measurable decrease in measured dose occurred with 5 mm water equivalent thick bolus material of areas '3 cm(2). As such, we recommend that 3 cm × 3 cm × 5 mm bolus build-up is the smallest size that should be placed over EBT3 Gafchromic film when used for accurate in vivo dosimetry for TBI applications. PMID:27217628

  13. Improving neutron dosimetry using bubble detector technology

    SciTech Connect

    Buckner, M.A.

    1993-02-01

    Providing accurate neutron dosimetry for a variety of neutron energy spectra is a formidable task for any dosimetry system. Unless something is known about the neutron spectrum prior to processing the dosimeter, the calculated dose may vary greatly from that actually encountered; that is until now. The entrance of bubble detector technology into the field of neutron dosimetry has eliminated the necessity of having an a priori knowledge of the neutron energy spectra. Recently, a new approach in measuring personnel neutron dose equivalent was developed at Oak Ridge National Laboratory. By using bubble detectors in combination with current thermoluminescent dosimeters (TLDs) as a Combination Personnel Neutron Dosimeter (CPND), not only is it possible to provide accurate dose equivalent results, but a simple four-interval neutron energy spectrum is obtained as well. The components of the CPND are a Harshaw albedo TLD and two bubble detectors with theoretical energy thresholds of 100 key and 1500 keV. Presented are (1) a synoptic history surrounding emergence of bubble detector technology, (2) a brief overview of the current theory on mechanisms of interaction, (3) the data and analysis process involved in refining the response functions, (4) performance evaluation of the original CPND and a reevaluation of the same data under the modified method, (5) the procedure used to determine the reference values of component fluence and dose equivalent for field assessment, (6) analysis of the after-modification results, (7) a critique of some currently held assumptions, offering some alternative explanations, and (8) thoughts concerning potential applications and directions for future research.

  14. In vivo light dosimetry for pleural PDT

    NASA Astrophysics Data System (ADS)

    Dimofte, Andreea; Zhu, Timothy C.; Finlay, Jarod C.; Culligan, Melissa; Edmonds, Christine E.; Friedberg, Joseph S.; Cengel, Keith; Hahn, Stephen M.

    2009-02-01

    In-vivo light Dosimetry for patients undergoing photodynamic therapy (PDT) is one of the important dosimetry quantities critical for predicting PDT outcome. This study examines the light fluence (rate) delivered to patients undergoing pleural PDT as a function of treatment time, treatment volume and surface area, and its accuracy as a function of the calibration accuracies of each isotropic detector and the calibration integrating sphere. The patients studied here were enrolled in Phase II clinical trial of Photofrin-mediated PDT for the treatment of non-small cell lung cancer with pleural effusion. The ages of the patients studied varied from 34 to 69 year old. All patients were administered 2mg per kg body weight Photoprin 24 hours before the surgery. Patients undergoing photodynamic therapy (PDT) are treated with laser light with a light fluence of 60 J/cm^2 at 630nm. Fluence rate (mW/cm^2) and cumulative fluence (J/cm^2) was monitored at 7 different sites during the entire light treatment delivery. Isotropic detectors were used for in-vivo light dosimetry. The anisotropy of each isotropic detector was found to be within 30%. The mean fluence rate delivery varied from 37.84 to 94.05 mW/cm^2 and treatment time varied from 1762 to 5232s. We have established a correlation between the treatment time and the treatment volume. The results are discussed using an integrating sphere theory and the measured tissue optical properties. The result can be used as a clinical guideline for future pleural PDT treatment.

  15. Model selection for radiochromic film dosimetry

    NASA Astrophysics Data System (ADS)

    Méndez, I.

    2015-05-01

    The purpose of this study was to find the most accurate model for radiochromic film dosimetry by comparing different channel independent perturbation models. A model selection approach based on (algorithmic) information theory was followed, and the results were validated using gamma-index analysis on a set of benchmark test cases. Several questions were addressed: (a) whether incorporating the information of the non-irradiated film, by scanning prior to irradiation, improves the results; (b) whether lateral corrections are necessary when using multichannel models; (c) whether multichannel dosimetry produces better results than single-channel dosimetry; (d) which multichannel perturbation model provides more accurate film doses. It was found that scanning prior to irradiation and applying lateral corrections improved the accuracy of the results. For some perturbation models, increasing the number of color channels did not result in more accurate film doses. Employing Truncated Normal perturbations was found to provide better results than using Micke-Mayer perturbation models. Among the models being compared, the triple-channel model with Truncated Normal perturbations, net optical density as the response and subject to the application of lateral corrections was found to be the most accurate model. The scope of this study was circumscribed by the limits under which the models were tested. In this study, the films were irradiated with megavoltage radiotherapy beams, with doses from about 20-600 cGy, entire (8 inch  × 10 inch) films were scanned, the functional form of the sensitometric curves was a polynomial and the different lots were calibrated using the plane-based method.

  16. Whence the red panda?

    PubMed

    Flynn, J J; Nedbal, M A; Dragoo, J W; Honeycutt, R L

    2000-11-01

    The evolutionary history of the red panda (Ailurus fulgens) plays a pivotal role in the higher-level phylogeny of the "bear-like" arctoid carnivoran mammals. Characters from morphology and molecules have provided inconsistent evidence for placement of the red panda. Whereas it certainly is an arctoid, there has been major controversy about whether it should be placed with the bears (ursids), ursids plus pinnipeds (seals, sea lions, walrus), raccoons (procyonids), musteloids (raccoons plus weasels, skunks, otters, and badgers [mustelids]), or as a monotypic lineage of uncertain phylogenetic affinities. Nucleotide sequence data from three mitochondrial genes and one nuclear intron were analyzed, with more complete taxonomic sampling of relevant taxa (arctoids) than previously available in analyses of primary molecular data, to clarify the phylogenetic relationships of the red panda to other arctoid carnivorans. This study provides detailed phylogenetic analyses (both parsimony and maximum-likelihood) of primary character data for arctoid carnivorans, including bootstrap and decay indices for all arctoid nodes, and three statistical tests of alternative phylogenetic hypotheses for the placement of the red panda. Combined phylogenetic analyses reject the hypotheses that the red panda is most closely related to the bears (ursids) or to the raccoons (procyonids). Rather, evidence from nucleotide sequences strongly support placement of the red panda within a broad Musteloidea (sensu lato) clade, including three major lineages (the red panda, the skunks [mephitids], and a clearly monophyletic clade of procyonids plus mustelids [sensu stricto, excluding skunks]). Within the Musteloidea, interrelationships of the three major lineages are unclear and probably are best considered an unresolved trichotomy. These data provide compelling evidence for the relationships of the red panda and demonstrate that small taxonomic sample sizes can result in misleading or possibly erroneous

  17. Characterization of the effect of MRI on Gafchromic film dosimetry.

    PubMed

    Reyhan, Meral L; Chen, Ting; Zhang, Miao

    2015-01-01

    Magnetic resonance (MR) imaging of Gafchromic film causes perturbation to absolute dosimetry measurements; the purpose of this work was to characterize the perturbation and develop a correction method for it. Three sets of Gafchromic EBT2 film were compared: radiation (control), radiation followed by MR imaging (RAD + B), and MR imaging followed by radiation (B + RAD). The T1-weighted and T2-weighted MR imaging was performed using a 1.5T scanner with the films wedged between two chicken legs. Doses from 0 to 800 cGy were delivered with a 6MV linac. The time interval between radiation and MR imaging was less than 10 min. Film calibration was generated from the red channel. Microscopic imaging was performed on two pieces of film. The effect of specific absorption rate (SAR) was determined by exposing another three sets of films to low, medium, and high levels of SAR through a series of pulse sequences. No discernible preferential alignment was detected on the microscopic images of the irradiated film exposed to MRI. No imaging artifacts were introduced by Gafchromic film on any MR images. On average, 4% dose difference was observed between B + RAD or RAD + B and the control, using the same calibration curve. The pixel values between the B + RAD or RAD + B and the control films were found to follow a linear relationship pixel(Control) = 1.02 × pixel(B + RAD or RAD + B). By applying this correction, the average dose error was reduced to approximately 2%. The SAR experiment revealed a dose overestimation with increasing SAR even when the correction was applied. It was concluded that MR imaging introduces perturbation on Gafchromic film dose measurements by 4% on average, compared to calibrating the film without the presence of MRI. This perturbation can be corrected by applying a linear correction to the pixel values. Additionally, Gafchromic film did not introduce any imaging artifacts in any of the MR images acquired. PMID:26699587

  18. USF/Russian dosimetry on STS-57

    NASA Technical Reports Server (NTRS)

    1995-01-01

    The major purpose of this experiment was to conduct an international comparison of passive dosimetry methods in space. Two APD's were flown in the charged particle directional spectrometer (CPDS)/tissue equivalent proportional counter (TEPC) locker on the space shuttle during the STS-57 mission. Due to placement, the shielding and radiation environment of the APD's were nearly the same and the dosimeters distributed in the two boxes can be considered equally exposed. The dosimeter types included plastic nuclear track detectors (PNTD's), thermoluminescent detectors (TLD), nuclear emulsions, and thermal/resonance neutron detectors (TRND's). The USF dosimeters included PNTD's, TLD's, and TRND's, while the Russian dosimeters included PNTD's, TLD's, and nuclear emulsions.

  19. Multisegmented ion chamber for CT scanner dosimetry

    SciTech Connect

    Moore, M.M.; Cacak, R.K.; Hendee, W.R.

    1981-01-01

    A multisegmented, ionization chamber capable of determining dosimetric profiles from a CT scanner has been developed and tested. The chamber consists of a number of 2 mm wide electrically isolated segments from which ionization currents may be measured. Presented here are the performance characteristics of the chamber including energy response, dose linearity, and corrections for ''cross talk'' between segments. Sample dosimetric profiles are depicted for 3 and 6 mm nominal beam widths at two locations in a dosimetric phantom positioned in the x-ray beam of a fourth generation CT scanner. The results agree well with the conventional method of obtaining dosimetry measurements with TLD chips.

  20. Neutron dosimetry of the Little Boy device

    SciTech Connect

    Pederson, R.A.; Plassmann, E.A.

    1984-01-01

    Neutron dose rates at several angular locations and at distances out to 0.5 mile have been measured during critical operation of the Little Boy replica. We used modified remmetes and thermoluminescent dosimetry techniques for the measurements. The present status of our analysis is presented including estimates of the neutron-dose-relaxation length in air and the variation of the neutron-to-gamma-ray dose ratio with distance from the replica. These results are preliminary and are subject to detector calibration measurements.

  1. Proton minibeam radiation therapy: Experimental dosimetry evaluation

    SciTech Connect

    Peucelle, C.; Martínez-Rovira, I.; Prezado, Y.; Nauraye, C.; Patriarca, A.; Hierso, E.; Fournier-Bidoz, N.

    2015-12-15

    Purpose: Proton minibeam radiation therapy (pMBRT) is a new radiotherapy (RT) approach that allies the inherent physical advantages of protons with the normal tissue preservation observed when irradiated with submillimetric spatially fractionated beams. This dosimetry work aims at demonstrating the feasibility of the technical implementation of pMBRT. This has been performed at the Institut Curie - Proton Therapy Center in Orsay. Methods: Proton minibeams (400 and 700 μm-width) were generated by means of a brass multislit collimator. Center-to-center distances between consecutive beams of 3200 and 3500 μm, respectively, were employed. The (passive scattered) beam energy was 100 MeV corresponding to a range of 7.7 cm water equivalent. Absolute dosimetry was performed with a thimble ionization chamber (IBA CC13) in a water tank. Relative dosimetry was carried out irradiating radiochromic films interspersed in a IBA RW3 slab phantom. Depth dose curves and lateral profiles at different depths were evaluated. Peak-to-valley dose ratios (PVDR), beam widths, and output factors were also assessed as a function of depth. Results: A pattern of peaks and valleys was maintained in the transverse direction with PVDR values decreasing as a function of depth until 6.7 cm. From that depth, the transverse dose profiles became homogeneous due to multiple Coulomb scattering. Peak-to-valley dose ratio values extended from 8.2 ± 0.5 at the phantom surface to 1.08 ± 0.06 at the Bragg peak. This was the first time that dosimetry in such small proton field sizes was performed. Despite the challenge, a complete set of dosimetric data needed to guide the first biological experiments was achieved. Conclusions: pMBRT is a novel strategy in order to reduce the side effects of RT. This works provides the experimental proof of concept of this new RT method: clinical proton beams might allow depositing a (high) uniform dose in a brain tumor located in the center of the brain (7.5 cm depth

  2. The next decade in external dosimetry

    SciTech Connect

    Griffith, R.V.

    1986-10-01

    As the radiation protection community moves through the last half of the '80s and into the next decade, we can expect the requirements for external dosimetry to become increasingly more restrictive and demanding. As in other health protection fields, growing regulatory and legal pressures, together with a natural evolution in philosophy, require the health physicist to display an increasing degree of accountability, rigor, and professionalism. The good news is that, for the most part, the technology necessary to solve many of the problems will be available or not far behind. This paper describes anticipated technology. 66 refs., 10 figs.

  3. Inhomogeneity in optical properties of rat brain: a study for LLLT dosimetry

    NASA Astrophysics Data System (ADS)

    Sousa, Marcelo V. P.; Prates, Renato; Kato, Ilka T.; Sabino, Caetano P.; Yoshimura, Tania M.; Suzuki, Luis C.; Magalhães, Ana C.; Yoshimura, Elisabeth M.; Ribeiro, Martha S.

    2013-03-01

    Over the last few years, low-level light therapy (LLLT) has shown an incredible suitability for a wide range of applications for central nervous system (CNS) related diseases. In this therapeutic modality light dosimetry is extremely critical so the study of light propagation through the CNS organs is of great importance. To better understand how light intensity is delivered to the most relevant neural sites we evaluated optical transmission through slices of rat brain point by point. We experimented red (λ = 660 nm) and near infrared (λ = 808 nm) diode laser light analyzing the light penetration and distribution in the whole brain. A fresh Wistar rat (Rattus novergicus) brain was cut in sagittal slices and illuminated with a broad light beam. A high-resolution digital camera was employed to acquire data of transmitted light. Spatial profiles of the light transmitted through the sample were obtained from the images. Peaks and valleys in the profiles show sites where light was less or more attenuated. The peak intensities provide information about total attenuation and the peak widths are correlated to the scattering coefficient at that individual portion of the sample. The outcomes of this study provide remarkable information for LLLT dose-dependent studies involving CNS and highlight the importance of LLLT dosimetry in CNS organs for large range of applications in animal and human diseases.

  4. Extended flow cytometry characterization of normal bone marrow progenitor cells by simultaneous detection of aldehyde dehydrogenase and early hematopoietic antigens: implication for erythroid differentiation studies

    PubMed Central

    Mirabelli, Peppino; Di Noto, Rosa; Lo Pardo, Catia; Morabito, Paolo; Abate, Giovanna; Gorrese, Marisa; Raia, Maddalena; Pascariello, Caterina; Scalia, Giulia; Gemei, Marica; Mariotti, Elisabetta; Del Vecchio, Luigi

    2008-01-01

    Background Aldehyde dehydrogenase (ALDH) is a cytosolic enzyme highly expressed in hematopoietic precursors from cord blood and granulocyte-colony stimulating factor mobilized peripheral blood, as well as in bone marrow from patients with acute myeloblastic leukemia. As regards human normal bone marrow, detailed characterization of ALDH+ cells has been addressed by one single study (Gentry et al, 2007). The goal of our work was to provide new information about the dissection of normal bone marrow progenitor cells based upon the simultaneous detection by flow cytometry of ALDH and early hematopoietic antigens, with particular attention to the expression of ALDH on erythroid precursors. To this aim, we used three kinds of approach: i) multidimensional analytical flow cytometry, detecting ALDH and early hematopoietic antigens in normal bone marrow; ii) fluorescence activated cell sorting of distinct subpopulations of progenitor cells, followed by in vitro induction of erythroid differentiation; iii) detection of ALDH+ cellular subsets in bone marrow from pure red cell aplasia patients. Results In normal bone marrow, we identified three populations of cells, namely ALDH+CD34+, ALDH-CD34+ and ALDH+CD34- (median percentages were 0.52, 0.53 and 0.57, respectively). As compared to ALDH-CD34+ cells, ALDH+CD34+ cells expressed the phenotypic profile of primitive hematopoietic progenitor cells, with brighter expression of CD117 and CD133, accompanied by lower display of CD38 and CD45RA. Of interest, ALDH+CD34- population disclosed a straightforward erythroid commitment, on the basis of three orders of evidences. First of all, ALDH+CD34- cells showed a CD71bright, CD105+, CD45- phenotype. Secondly, induction of differentiation experiments evidenced a clear-cut expression of glycophorin A (CD235a). Finally, ALDH+CD34- precursors were not detectable in patients with pure red cell aplasia (PRCA). Conclusion Our study, comparing surface antigen expression of ALDH+/CD34+, ALDH

  5. Pathophysiological role of enhanced bone marrow adipogenesis in diabetic complications

    PubMed Central

    Piccinin, Meghan A; Khan, Zia A

    2014-01-01

    Diabetes leads to complications in select organ systems primarily by disrupting the vasculature of the target organs. These complications include both micro- (cardiomyopathy, retinopathy, nephropathy, and neuropathy) and macro-(atherosclerosis) angiopathies. Bone marrow angiopathy is also evident in both experimental models of the disease as well as in human diabetes. In addition to vascular disruption, bone loss and increased marrow adiposity have become hallmarks of the diabetic bone phenotype. Emerging evidence now implicates enhanced marrow adipogenesis and changes to cellular makeup of the marrow in a novel mechanistic link between various secondary complications of diabetes. In this review, we explore the mechanisms of enhanced marrow adipogenesis in diabetes and the link between changes to marrow cellular composition, and disruption and depletion of reparative stem cells. PMID:26317050

  6. Bone marrow transfusions in previously irradiated, hematologically normal syngeneic mice

    SciTech Connect

    Brecher, G.; Lawce, H.; Tjio, J.H.

    1981-03-01

    Transfusion of syngeneic marrow into normal, nonirradiated recipients results only in minimal proliferation of donor cells. However, irradiated recipients, restored to hematologic normalcy by an initial marrow transfusion, subsequently sustain proliferation which replaces approximately 10% of endogenous marrow after a single transfusion of 4 x 10/sup 7/ marrow cells of the same strain as the host. Cells from histoincompatible donors proliferate only rarely or minimally in the marrows of these irradiated, but hematologically normal recipients without reirradiation. Syngeneic male donor cells proliferate in irradiated and restored female mice, while female donor cells fail to proliferate in the marrow of syngeneic male recipients. A possible explanation is that transfused female cells respond immunologically to the abundant H-Y antigen in the male environment and are eliminated as a result.

  7. Bone marrow ablation followed by allogeneic marrow grafting during first complete remission of acute nonlymphocytic leukemia

    SciTech Connect

    Forman, S.J.; Spruce, W.E.; Farbstein, M.J.

    1983-03-01

    Of 33 patients who had undergone allogeneic bone marrow transplantation during first complete remission of acute nonlymphocytic leukemia, 21 patients have now been followed in continued complete remission for 6-64 mo (median greater than 18 mo) without maintenance chemotherapy. The median age of the surviving patients is 27 yr. Transplant-related complications occurring throughout the first year after marrow grafting were fatal in 7 patients, and leukemic recurrence led to the death of 5 patients. The actuarial long-term disease-free survival is 60% and the actuarial remission rate is 79%.

  8. In vivo photoacoustic monitoring of photosensitizer in skin: application to dosimetry for antibacterial photodynamic treatment

    NASA Astrophysics Data System (ADS)

    Hirao, Akihiro; Sato, Shunichi; Saitoh, Daizoh; Shinomiya, Nariyoshi; Ashida, Hiroshi; Obara, Minoru

    2009-02-01

    To obtain efficient antibacterial photodynamic effect in traumatic injuries such as burns, depth-resolved dosimetry of photosensitizer is required. In this study, we performed dual-wavelength photoacoustic (PA) measurement for rat burned skins injected with a photosensitizer. As a photosensitizer, methylene blue (MB) or porfimer sodium was injected into the subcutaneous tissue in rats with deep dermal burn. The wound was irradiated with red (665 nm or 630 nm) pulsed light to excite photosensitizers and green (532 nm) pulsed light to excite blood in the tissue; the latter signal was used to eliminate blood-associated component involved in the former signal. Acoustic attenuation was also compensated from the photosensitizer-associated PA signals. These signal processing was effective to obtain high-contrast image of a photosensitizer in the tissue. Behaviors of MB and porfimer sodium in the tissue were compared.

  9. Vertebral hyperemia associated with bone marrow insult and recovery

    SciTech Connect

    Klein, H.A.; Bolden, R.O.; Simone, F.J.

    1984-06-01

    A 15-year-old boy with rhabdoid sarcoma received chemotherapy, which was followed by bone marrow depression, massive nosebleeds and, finally, hematologic recovery. On both hepatobiliary and renal scintigraphy, prominent vertebral activity was present in early images. Correlation with his clinical course suggests that the findings reflect hyperemia due to marrow insult and recovery. Radionuclide imaging to detect hyperemia may be a useful probe for drug effects on hematopoietic bone marrow.

  10. Comparison of vidar dosimetry advantage pro and epson perfection V700 scanner in densitometry of radiochomic EBT2 film in measurement of high dose gradient

    NASA Astrophysics Data System (ADS)

    Bura, W.; Tangboonduangjit, P.; Damrongkijudom, N.

    2016-03-01

    Nowadays the radiochromic film is widely used to obtain dose distribution in two dimensions with high spatial resolution, less energy dependence and near tissue equivalent. It can be a commissioning tool to verify high dose gradient of dose distribution for IMRT and VMAT techniques. However, the film scanner could affect the accuracy of dose distribution if lack of precaution. In this study, the comparison between Epson perfection V700 and Vidar Dosimetry Pro Advantage (RED) is evaluated in terms of the capability to verify the 2D dose distribution for conventional and VMAT techniques. The Gafchromic® EBT2 films were read from two types of scanners (Epson perfection V700 and Vidar Dosimetry Pro Advantage) for volumetric modulated radiation therapy (VMAT) dosimetry. The software for analyzing the results of Epson perfection V700 and Vidar Dosimetry Pro Advantage are SNC Patient software and Omnipro’ IMRT software, respectively. Comparisons between measured and calculated dose distributions are reported as %passing rate and the gamma index for tolerance parameters of 3% and 3mm. The study found that the %passing rate obtained from Vidar scanner and Epson V700 scanner compared with Eclipse treatment planning system is more than 98% with the criteria of (3%/3mm).

  11. Effect of processor temperature on film dosimetry

    SciTech Connect

    Srivastava, Shiv P.; Das, Indra J.

    2012-07-01

    Optical density (OD) of a radiographic film plays an important role in radiation dosimetry, which depends on various parameters, including beam energy, depth, field size, film batch, dose, dose rate, air film interface, postexposure processing time, and temperature of the processor. Most of these parameters have been studied for Kodak XV and extended dose range (EDR) films used in radiation oncology. There is very limited information on processor temperature, which is investigated in this study. Multiple XV and EDR films were exposed in the reference condition (d{sub max.}, 10 Multiplication-Sign 10 cm{sup 2}, 100 cm) to a given dose. An automatic film processor (X-Omat 5000) was used for processing films. The temperature of the processor was adjusted manually with increasing temperature. At each temperature, a set of films was processed to evaluate OD at a given dose. For both films, OD is a linear function of processor temperature in the range of 29.4-40.6 Degree-Sign C (85-105 Degree-Sign F) for various dose ranges. The changes in processor temperature are directly related to the dose by a quadratic function. A simple linear equation is provided for the changes in OD vs. processor temperature, which could be used for correcting dose in radiation dosimetry when film is used.

  12. Investigation of the dosimetry of chest tomosynthesis

    NASA Astrophysics Data System (ADS)

    Svalkvist, Angelica; Zachrisson, Sara; Månsson, Lars Gunnar; Båth, Magnus

    2009-02-01

    Chest tomosynthesis has recently been introduced to healthcare as a low-dose alternative to CT or as a tool for improved diagnostics in chest radiography with only a modest increase in radiation dose to the patient. However, no detailed description of the dosimetry for this type of examination has been presented. The aim of this work was therefore to investigate the dosimetry of chest tomosynthesis. The chest tomosynthesis examination was assumed to be performed using a stationary detector and a vertically moving x-ray tube, exposing the patient from different angles. The Monte Carlo based computer software PCXMC was used to determine the effective dose delivered to a standard-sized patient from various angles using different assumptions of the distribution of the effective dose over the different projections. The obtained conversion factors between input dose measures and effective dose for chest tomosynthesis for different angular intervals were then compared with the horizontal projection. The results indicate that the error introduced by using conversion factors for the PA projection in chest radiography for estimating the effective dose of chest tomosynthesis is small for normally sized patients, especially if a conversion factor between KAP and effective dose is used.

  13. Numerical dosimetry dedicated to children RF exposure.

    PubMed

    Wiart, Joe; Hadjem, Abdelhamid; Varsier, Nadège; Conil, Emmanuelle

    2011-12-01

    Children are more and more using wireless communication systems. This growth has strengthened public concern and has highlighted the need to assess the radio frequency (RF) exposure of children. In dosimetry, taking advantage of the improvement of High Performance Calculation systems, great efforts have been carried out to improve the numerical tools and human models used to assess the Specific Absorption Rate (SAR). This paper analyses progress in building child and foetus models for numerical dosimetry purpose. The simulation results, in terms of Specific Absorption Rate over 1 and 10 g of tissues, in specific organs such as brain and averaged over the whole body, are reported and analysed. The results show that compliance methods used nowadays to certify phones are valid for children. The studies also show that specific tissues such as peripheral brain tissues can have higher exposure with children than with adults. Studies performed with plane waves as sources and whole body children models show that the whole body SAR of children can be higher than the WBSAR of adults and that the compliance to ICNIRP reference levels does not guarantee the compliance to ICNIRP basic restrictions. Dealing with the foetus models and dielectric properties great efforts have been made. Preliminary results show that the foetus exposure is often lower than the mother exposure, with an important influencing parameter: the foetus position in the uterus. PMID:22005525

  14. Dosimetry of inhaled radon and thoron progeny

    SciTech Connect

    James, A.C.

    1994-06-01

    This chapter reviews recent developments in modeling doses received by lung tissues, with particular emphasis on application of ICRP`s new dosimetric model of the respiratory tract for extrapolating to other environments the established risks from exposure to radon progeny in underground mines. Factors discussed include: (1) the influence of physical characteristics of radon progeny aerosols on dose per unit exposure, e.g., the unattached fraction, and the activity-size distributions of clustered and attached progeny; (2) the dependence of dose on breathing rate, and on the exposed subject (man, woman or child); (3) the variability of dose per unit exposure in a home when exposure is expressed in terms of potential {alpha} energy or radon gas concentration; (4) the comparative dosimetry of thoron progeny; and (5) the effects of air-cleaning on lung dose. Also discussed is the apparent discrepancy between lung cancer risk estimates derived purely from dosimetry and the lung cancer incidence observed in the epidemiological studies of radon-exposed underground miners. Application of ICRP`s recommended risk factors appears to overestimate radon lung-cancer risk for miners by a factor of three. ``Normalization`` of the calculated effective dose is therefore needed, at least for {alpha} dose from radon and thoron progeny, in order to obtain a realistic estimate of lung cancer risk.

  15. Eleventh DOE workshop on personnel neutron dosimetry

    SciTech Connect

    Not Available

    1991-12-31

    Since its formation, the Office of Health (EH-40) has stressed the importance of the exchange of information related to and improvements in neutron dosimetry. This Workshop was the eleventh in the series sponsored by the Department of Energy (DOE). It provided a forum for operational personnel at DOE facilities to discuss current issues related to neutron dosimetry and for leading investigators in the field to discuss promising approaches for future research. A total of 26 papers were presented including the keynote address by Dr. Warren K. Sinclair, who spoke on, ``The 1990 Recommendations of the ICRP and their Biological Background.`` The first several papers discussed difficulties in measuring neutrons of different energies and ways of compensating or deriving correction factors at individual facilities. Presentations were also given by the US Navy and Air Force. Current research in neutron dosimeter development was the subject of the largest number of papers. These included a number on the development of neutron spectrometers. Selected papers were processed separately for inclusion in the Energy Science and Technology Database.

  16. The importance of 3D dosimetry

    NASA Astrophysics Data System (ADS)

    Low, Daniel

    2015-01-01

    Radiation therapy has been getting progressively more complex for the past 20 years. Early radiation therapy techniques needed only basic dosimetry equipment; motorized water phantoms, ionization chambers, and basic radiographic film techniques. As intensity modulated radiation therapy and image guided therapy came into widespread practice, medical physicists were challenged with developing effective and efficient dose measurement techniques. The complex 3-dimensional (3D) nature of the dose distributions that were being delivered demanded the development of more quantitative and more thorough methods for dose measurement. The quality assurance vendors developed a wide array of multidetector arrays that have been enormously useful for measuring and characterizing dose distributions, and these have been made especially useful with the advent of 3D dose calculation systems based on the array measurements, as well as measurements made using film and portal imagers. Other vendors have been providing 3D calculations based on data from the linear accelerator or the record and verify system, providing thorough evaluation of the dose but lacking quality assurance (QA) of the dose delivery process, including machine calibration. The current state of 3D dosimetry is one of a state of flux. The vendors and professional associations are trying to determine the optimal balance between thorough QA, labor efficiency, and quantitation. This balance will take some time to reach, but a necessary component will be the 3D measurement and independent calculation of delivered radiation therapy dose distributions.

  17. PDT dose dosimetry for pleural photodynamic therapy

    NASA Astrophysics Data System (ADS)

    Sharikova, Anna V.; Finlay, Jarod C.; Liang, Xing; Zhu, Timothy C.

    2013-03-01

    PDT dose is the product of the photosensitizer concentration and the light fluence in target tissue. Although existing systems are capable of measuring the light fluence in vivo, the concurrent measurement of photosensitizer in the treated tissue so far has been lacking. We have developed and tested a new method to simultaneously acquire light dosimetry and photosensitizer fluorescence data via the same isotropic detector, employing treatment light as the excitation source. A dichroic beamsplitter is used to split light from the isotropic detector into two fibers, one for light dosimetry, the other, after the 665 nm treatment light is removed by a band-stop filter, to a spectrometer for fluorescence detection. The light fluence varies significantly during treatment because of the source movement. The fluorescence signal is normalized by the light fluence measured at treatment wavelength. We have shown that the absolute photosensitizer concentration can be obtained by an optical properties correction factor and linear spectral fitting. Tissue optical properties are determined using an absorption spectroscopy probe immediately before PDT at the same sites. This novel method allows accurate real-time determination of delivered PDT dose using existing isotropic detectors, and may lead to a considerable improvement of PDT treatment quality compared to the currently employed systems. Preliminary data in patient studies is presented.

  18. An absorbed dose calorimeter for IMRT dosimetry

    NASA Astrophysics Data System (ADS)

    Duane, S.; Aldehaybes, M.; Bailey, M.; Lee, N. D.; Thomas, C. G.; Palmans, H.

    2012-10-01

    A new calorimeter for dosimetry in small and complex fields has been built. The device is intended for the direct determination of absorbed dose to water in moderately small fields and in composite fields such as IMRT treatments, and as a transfer instrument calibrated against existing absorbed dose standards in conventional reference conditions. The geometry, materials and mode of operation have been chosen to minimize detector perturbations when used in a water phantom, to give a reasonably isotropic response and to minimize the effects of heat transfer when the calorimeter is used in non-reference conditions in a water phantom. The size of the core is meant to meet the needs of measurement in IMRT treatments and is comparable to the size of the air cavity in a type NE2611 ionization chamber. The calorimeter may also be used for small field dosimetry. Initial measurements in reference conditions and in an IMRT head and neck plan, collapsed to gantry angle zero, have been made to estimate the thermal characteristics of the device, and to assess its performance in use. The standard deviation (estimated repeatability) of the reference absorbed dose measurements was 0.02 Gy (0.6%).

  19. Dosimetry of radium-223 and progeny

    SciTech Connect

    Fisher, D.R.; Sgouros, G.

    1999-01-01

    Radium-223 is a short-lived (11.4 d) alpha emitter with potential applications in radioimmunotherapy of cancer. Radium-223 can be complexed and linked to protein delivery molecules for specific tumor-cell targeting. It decays through a cascade of short-lived alpha- and beta-emitting daughters with emission of about 28 MeV of energy through complete decay. The first three alpha particles are essentially instantaneous. Photons associated with Ra-223 and progeny provide the means for tumor and normal-organ imaging and dosimetry. Two beta particles provide additional therapeutic value. Radium-223 may be produced economically and in sufficient amounts for widescale application. Many aspects of the chemistry of carrier-free isotope preparation, complexation, and linkage to the antibody have been developed and are being tested. The radiation dosimetry of a Ra-223-labeled antibody shows favorable tumor to normal tissue dose ratios for therapy. The 11.4-d half-life of Ra-223 allows sufficient time for immunoconjugate preparation, administration, and tumor localization by carrier antibodies before significant radiological decay takes place. If 0.01 percent of a 37 MBq (1 mCi) injection deposits in a one gram tumor mass, and if the activity is retained with a typical effective half-time (75 h), the absorbed dose will be 163 mGy MBq{sup {minus}1} (600 rad mCi{sup {minus}1}) administered. 49 refs., 5 figs., 2 tabs.

  20. Bone marrow fibrosis in childhood acute lymphoblastic leukaemia.

    PubMed Central

    Wallis, J P; Reid, M M

    1989-01-01

    Bone marrow trephine biopsy specimens were obtained at diagnosis from 63 of 76 consecutively presenting children with acute lymphoblastic leukaemia (ALL). The association between marrow fibrosis and presenting features, including immunophenotype, was analysed. Reticulin was increased in 45 of 56 cases in which blasts expressed B lineage markers, but in only one of seven with T-ALL. A weak association was also found between marrow fibrosis and splenomegaly in those with common ALL. Marrow fibrosis is apparently associated with some examples of ALL of B cell lineage, but precisely which subtypes and whether the phenomenon is clinically important remain to be determined. PMID:2613918

  1. Bone marrow fibrosis in myelofibrosis: pathogenesis, prognosis and targeted strategies

    PubMed Central

    Zahr, Abdallah Abou; Salama, Mohamed E.; Carreau, Nicole; Tremblay, Douglas; Verstovsek, Srdan; Mesa, Ruben; Hoffman, Ronald; Mascarenhas, John

    2016-01-01

    Bone marrow fibrosis is a central pathological feature and World Health Organization major diagnostic criterion of myelofibrosis. Although bone marrow fibrosis is seen in a variety of malignant and non-malignant disease states, the deposition of reticulin and collagen fibrosis in the bone marrow of patients with myelofibrosis is believed to be mediated by the myelofibrosis hematopoietic stem/progenitor cell, contributing to an impaired microenvironment favoring malignant over normal hematopoiesis. Increased expression of inflammatory cytokines, lysyl oxidase, transforming growth factor-β, impaired megakaryocyte function, and aberrant JAK-STAT signaling have all been implicated in the pathogenesis of bone marrow fibrosis. A number of studies indicate that bone marrow fibrosis is an adverse prognostic variable in myeloproliferative neoplasms. However, modern myelofibrosis prognostication systems utilized in risk-adapted treatment approaches do not include bone marrow fibrosis as a prognostic variable. The specific effect on bone marrow fibrosis of JAK2 inhibition, and other rationally based therapies currently being evaluated in myelofibrosis, has yet to be fully elucidated. Hematopoietic stem cell transplantation remains the only curative therapeutic approach that reliably results in resolution of bone marrow fibrosis in patients with myelofibrosis. Here we review the pathogenesis, biological consequences, and prognostic impact of bone marrow fibrosis. We discuss the rationale of various anti-fibrogenic treatment strategies targeting the clonal hematopoietic stem/progenitor cell, aberrant signaling pathways, fibrogenic cytokines, and the tumor microenvironment. PMID:27252511

  2. Marrow Fat and Bone: Review of Clinical Findings

    PubMed Central

    Schwartz, Ann V.

    2015-01-01

    With growing interest in the connection between fat and bone, there has been increased investigation of the relationship with marrow fat in particular. Clinical research has been facilitated by the development of non-invasive methods to measure bone marrow fat content and composition. Studies in different populations using different measurement techniques have established that higher marrow fat is associated with lower bone density and prevalent vertebral fracture. The degree of unsaturation in marrow fat may also affect bone health. Although other fat depots tend to be strongly correlated, marrow fat has a distinct pattern, suggesting separate mechanisms of control. Longitudinal studies are limited, but are crucial to understand the direct and indirect roles of marrow fat as an influence on skeletal health. With greater appreciation of the links between bone and energy metabolism, there has been growing interest in understanding the relationship between marrow fat and bone. It is well established that levels of marrow fat are higher in older adults with osteoporosis, defined by either low bone density or vertebral fracture. However, the reasons for and implications of this association are not clear. This review focuses on clinical studies of marrow fat and its relationship to bone. PMID:25870585

  3. Bone marrow fibrosis in myelofibrosis: pathogenesis, prognosis and targeted strategies.

    PubMed

    Zahr, Abdallah Abou; Salama, Mohamed E; Carreau, Nicole; Tremblay, Douglas; Verstovsek, Srdan; Mesa, Ruben; Hoffman, Ronald; Mascarenhas, John

    2016-06-01

    Bone marrow fibrosis is a central pathological feature and World Health Organization major diagnostic criterion of myelofibrosis. Although bone marrow fibrosis is seen in a variety of malignant and non-malignant disease states, the deposition of reticulin and collagen fibrosis in the bone marrow of patients with myelofibrosis is believed to be mediated by the myelofibrosis hematopoietic stem/progenitor cell, contributing to an impaired microenvironment favoring malignant over normal hematopoiesis. Increased expression of inflammatory cytokines, lysyl oxidase, transforming growth factor-β, impaired megakaryocyte function, and aberrant JAK-STAT signaling have all been implicated in the pathogenesis of bone marrow fibrosis. A number of studies indicate that bone marrow fibrosis is an adverse prognostic variable in myeloproliferative neoplasms. However, modern myelofibrosis prognostication systems utilized in risk-adapted treatment approaches do not include bone marrow fibrosis as a prognostic variable. The specific effect on bone marrow fibrosis of JAK2 inhibition, and other rationally based therapies currently being evaluated in myelofibrosis, has yet to be fully elucidated. Hematopoietic stem cell transplantation remains the only curative therapeutic approach that reliably results in resolution of bone marrow fibrosis in patients with myelofibrosis. Here we review the pathogenesis, biological consequences, and prognostic impact of bone marrow fibrosis. We discuss the rationale of various anti-fibrogenic treatment strategies targeting the clonal hematopoietic stem/progenitor cell, aberrant signaling pathways, fibrogenic cytokines, and the tumor microenvironment. PMID:27252511

  4. TG-69: radiographic film for megavoltage beam dosimetry.

    PubMed

    Pai, Sujatha; Das, Indra J; Dempsey, James F; Lam, Kwok L; Losasso, Thomas J; Olch, Arthur J; Palta, Jatinder R; Reinstein, Lawrence E; Ritt, Dan; Wilcox, Ellen E

    2007-06-01

    TG-69 is a task group report of the AAPM on the use of radiographic film for dosimetry. Radiographic films have been used for radiation dosimetry since the discovery of x-rays and have become an integral part of dose verification for both routine quality assurance and for complex treatments such as soft wedges (dynamic and virtual), intensity modulated radiation therapy (IMRT), image guided radiation therapy (IGRT), and small field dosimetry like stereotactic radiosurgery. Film is convenient to use, spatially accurate, and provides a permanent record of the integrated two dimensional dose distributions. However, there are several challenges to obtaining high quality dosimetric results with film, namely, the dependence of optical density on photon energy, field size, depth, film batch sensitivity differences, film orientation, processing conditions, and scanner performance. Prior to the clinical implementation of a film dosimetry program, the film, processor, and scanner need to be tested to characterize them with respect to these variables. Also, the physicist must understand the basic characteristics of all components of film dosimetry systems. The primary mission of this task group report is to provide guidelines for film selection, irradiation, processing, scanning, and interpretation to allow the physicist to accurately and precisely measure dose with film. Additionally, we present the basic principles and characteristics of film, processors, and scanners. Procedural recommendations are made for each of the steps required for film dosimetry and guidance is given regarding expected levels of accuracy. Finally, some clinical applications of film dosimetry are discussed. PMID:17654924

  5. Dosimetry of ionising radiation in modern radiation oncology

    NASA Astrophysics Data System (ADS)

    Kron, Tomas; Lehmann, Joerg; Greer, Peter B.

    2016-07-01

    Dosimetry of ionising radiation is a well-established and mature branch of physical sciences with many applications in medicine and biology. In particular radiotherapy relies on dosimetry for optimisation of cancer treatment and avoidance of severe toxicity for patients. Several novel developments in radiotherapy have introduced new challenges for dosimetry with small and dynamically changing radiation fields being central to many of these applications such as stereotactic ablative body radiotherapy and intensity modulated radiation therapy. There is also an increasing awareness of low doses given to structures not in the target region and the associated risk of secondary cancer induction. Here accurate dosimetry is important not only for treatment optimisation but also for the generation of data that can inform radiation protection approaches in the future. The article introduces some of the challenges and highlights the interdependence of dosimetric calculations and measurements. Dosimetric concepts are explored in the context of six application fields: reference dosimetry, small fields, low dose out of field, in vivo dosimetry, brachytherapy and auditing of radiotherapy practice. Recent developments of dosimeters that can be used for these purposes are discussed using spatial resolution and number of dimensions for measurement as sorting criteria. While dosimetry is ever evolving to address the needs of advancing applications of radiation in medicine two fundamental issues remain: the accuracy of the measurement from a scientific perspective and the importance to link the measurement to a clinically relevant question. This review aims to provide an update on both of these.

  6. Dosimetry of ionising radiation in modern radiation oncology.

    PubMed

    Kron, Tomas; Lehmann, Joerg; Greer, Peter B

    2016-07-21

    Dosimetry of ionising radiation is a well-established and mature branch of physical sciences with many applications in medicine and biology. In particular radiotherapy relies on dosimetry for optimisation of cancer treatment and avoidance of severe toxicity for patients. Several novel developments in radiotherapy have introduced new challenges for dosimetry with small and dynamically changing radiation fields being central to many of these applications such as stereotactic ablative body radiotherapy and intensity modulated radiation therapy. There is also an increasing awareness of low doses given to structures not in the target region and the associated risk of secondary cancer induction. Here accurate dosimetry is important not only for treatment optimisation but also for the generation of data that can inform radiation protection approaches in the future. The article introduces some of the challenges and highlights the interdependence of dosimetric calculations and measurements. Dosimetric concepts are explored in the context of six application fields: reference dosimetry, small fields, low dose out of field, in vivo dosimetry, brachytherapy and auditing of radiotherapy practice. Recent developments of dosimeters that can be used for these purposes are discussed using spatial resolution and number of dimensions for measurement as sorting criteria. While dosimetry is ever evolving to address the needs of advancing applications of radiation in medicine two fundamental issues remain: the accuracy of the measurement from a scientific perspective and the importance to link the measurement to a clinically relevant question. This review aims to provide an update on both of these. PMID:27351409

  7. PREFACE: Third International Conference on Radiotherapy Gel Dosimetry

    NASA Astrophysics Data System (ADS)

    DeDeene, Yves; Baldock, Clive

    2004-01-01

    Gel dosimetry is not merely another dosimetry technique. Gel dosimeters are integrating dosimeters that enable dose verification in three dimensions. The application of a 3D dosimetry technique in the clinic would give a real push to the implementation of advanced high-precision radiotherapy technologies in many institutes. It can be expected that with the recent developments in the field towards more user-friendly gel systems and imaging modalities, gel dosimetry will become a vital link in the chain of high-precision radiation cancer therapy in the near future. Many researchers all over the world have contributed to the emerging technology of gel dosimetry. The research field of gel dosimetry is recognized to be very broad from polymer and analytical chemistry and material research to imaging technologies. The DOSGEL conferences in the past have proven to be an important forum at which material scientists, chemists, medical physicists, magnetic resonance imaging and radiation specialists brought together a critical mass of thoughts, findings and considerations. DOSGEL 2004 has been endorsed by many international, supra-national and national medical physics organizations and publishers. These proceedings contain 51 papers that cover various aspects of gel dosimetry.

  8. Hanford External Dosimetry Technical Basis Manual PNL-MA-842

    SciTech Connect

    Rathbone, Bruce A.

    2009-08-28

    The Hanford External Dosimetry Technical Basis Manual PNL-MA-842 documents the design and implementation of the external dosimetry system used at Hanford. The manual describes the dosimeter design, processing protocols, dose calculation methodology, radiation fields encountered, dosimeter response characteristics, limitations of dosimeter design under field conditions, and makes recommendations for effective use of the dosimeters in the field. The manual describes the technical basis for the dosimetry system in a manner intended to help ensure defensibility of the dose of record at Hanford and to demonstrate compliance with 10 CFR 835, DOELAP, DOE-RL, ORP, PNSO, and Hanford contractor requirements. The dosimetry system is operated by PNNL’s Hanford External Dosimetry Program (HEDP) which provides dosimetry services to all Hanford contractors. The primary users of this manual are DOE and DOE contractors at Hanford using the dosimetry services of PNNL. Development and maintenance of this manual is funded directly by DOE and DOE contractors. Its contents have been reviewed and approved by DOE and DOE contractors at Hanford through the Hanford Personnel Dosimetry Advisory Committee (HPDAC) which is chartered and chaired by DOE-RL and serves as means of coordinating dosimetry practices across contractors at Hanford. This manual was established in 1996. Since inception, it has been revised many times and maintained by PNNL as a controlled document with controlled distribution. The first revision to be released through PNNL’s Electronic Records & Information Capture Architecture (ERICA) database was designated Revision 0. Revision numbers that are whole numbers reflect major revisions typically involving changes to all chapters in the document. Revision numbers that include a decimal fraction reflect minor revisions, usually restricted to selected chapters or selected pages in the document.

  9. Practical IMRT QA dosimetry using Gafchromic film: a quick start guide.

    PubMed

    Bennie, Nick; Metcalfe, Peter

    2016-06-01

    This work outlines a method for using Gafchromic film for dosimetry purposes, by scanning it with currently available commercial scanners. The scanners used were: Epson V800, Epson V700, Epson V37 series, specifically a V370 and a Canon multi-function office printer/scanner. The Epson scanners have 16 bit RGB resolution, the Canon has 8 bit RGB (Red Green Blue) resolution, and the V800 and V700 allow scanning in transmission mode. The V700 uses an Epson White Cold Cathode Florescent Lamp; the recently released V800 uses an Epson light emitting diode (LED) light source, while the V37 series uses a reflective mode and the Epson LED light source. The Epson V37 series scanners are designed for non-professional use so the cost has been kept at a low "entry level" point, so they would be a suitable option for a department wanting to use Gafchromic film or with limited needs that did not justify a more sophisticated and expensive unit. Note that the V800 or V700 scanners are not expensive in context, costing approximately the same as a 25 sheet box of Gafchromic film. The Canon was included to demonstrate that a scanner with 8 bit RGB resolution can be used for dosimetry. These general multi-function units are available in most departments, and they would allow Gafchromic film to be evaluated as a dosimetry tool without a significant investment. Furthermore, they are generally capable of scanning large format film (425 × 350 mm) in one part. Although this is not necessary for dosimetry, it is often useful for machine QA, where dividing the film into two parts to ensure accurate measurements is not practical. Moreover, this analytical method uses software that is freely or commonly available, particularly the image processing package ImageJ. Note ImageJ v1.48 was the version used. The results demonstrate that this method used with the scanners evaluated is a practical method of using Gafchromic film as a dosimeter for IMRT QA. PMID:27098156

  10. Holoprosencephaly and Pure Red Cell Aplasia in a Feline Leukaemia Virus-Positive Kitten.

    PubMed

    Southard, T L; Rodriguez-Ramos Fernandez, J; Priest, H; Stokol, T

    2016-01-01

    A 9-month-old, female, domestic longhair cat with severe anaemia tested positive for feline leukaemia virus (FeLV) and was humanely destroyed and submitted for necropsy examination. Gross findings included a non-divided rostral telencephalon, consistent with semilobar holoprosencephaly. Histological examination of the bone marrow revealed an almost complete absence of erythroid precursor cells, consistent with pure red cell aplasia, and mild to moderate myelofibrosis. This case demonstrates a very unusual central nervous system defect, as well as an atypical presentation of pure red cell aplasia, in a FeLV-positive kitten. PMID:26897097

  11. Bone marrow and bone marrow derived mononuclear stem cells therapy for the chronically ischemic myocardium

    SciTech Connect

    Waksman, Ron; Baffour, Richard

    2003-09-01

    Bone marrow stem cells have been shown to differentiate into various phenotypes including cardiomyocytes, vascular endothelial cells and smooth muscle. Bone marrow stem cells are mobilized and home in to areas of injured myocardium where they are involved in tissue repair. In addition, bone marrow secretes multiple growth factors, which are essential for angiogenesis and arteriogenesis. In some patients, these processes are not enough to avert clinical symptoms of ischemic disease. Therefore, in vivo administration of an adequate number of stem cells would be a significant therapeutic advance. Unfractionated bone marrow derived mononuclear stem cells, which contain both hematopoietic and nonhematopoietic cells may be more appropriate for cell therapy. Studies in animal models suggest that implantation of different types of stem cells improve angiogenesis and arteriogenesis, tissue perfusion as well as left ventricular function. Several unanswered questions remain. For example, the optimal delivery approach, dosage and timing of the administration of cell therapy as well as durability of improvements need to be studied. Early clinical studies have demonstrated safety and feasibility of various cell therapies in ischemic disease. Randomized, double blind and placebo-controlled clinical trials need to be completed to determine the effectiveness of stem cell.

  12. Metastatic thymoma involving the bone marrow

    PubMed Central

    Wenceslao, Stella; Krause, John R.

    2016-01-01

    Although relatively rare, thymomas can be involved in a considerable variety of clinical presentations. Clinicians should be mindful of the breadth of associations with other diseases, including autoimmune disorders and many secondary nonthymic malignancies. For the pathologist, knowledge of the extremely varied histopathologic presentation of thymoma is vital to formulate a proper differential, workup, and diagnosis. The presented case illustrates the finding of very rare metastatic thymoma involvement of bone marrow, identified during evaluation for pancytopenia. The history of prior prostate cancer and an uncharacterized pancreatic lesion, as well as the familial presentation, also suggests a possible underlying hereditary syndrome. PMID:26722174

  13. The inherited bone marrow failure syndromes.

    PubMed

    Chirnomas, S Deborah; Kupfer, Gary M

    2013-12-01

    Molecular pathogenesis may be elucidated for inherited bone marrow failure syndromes (IBMFS). The study and presentation of the details of their molecular biology and biochemistry is warranted for appropriate diagnosis and management of afflicted patients and to identify the physiology of the normal hematopoiesis and mechanisms of carcinogenesis. Several themes have emerged within each subsection of IBMFS, including the ribosomopathies, which include ribosome assembly and ribosomal RNA processing. The Fanconi anemia pathway has become interdigitated with the familial breast cancer syndromes. In this article, the diseases that account for most IBMFS diagnoses are analyzed. PMID:24237972

  14. Autologous bone marrow transplantation by photodynamic therapy

    NASA Astrophysics Data System (ADS)

    Gulliya, Kirpal S.

    1992-06-01

    Simultaneous exposure of Merocyanine 540 dye containing cultured tumor cells to 514-nm laser light (93.6 J/cm2) results in virtually complete cell destruction. Under identical conditions, 40% of the normal progenitor (CFU-GM) cells survive the treatment. Laser- photoradiation treated, cultured breast cancer cells also were killed, and living tumor cells could not be detected by clonogenic assays or by anti-cytokeratin monoclonal antibody method. Thus, laser photoradiation therapy could be useful for purging of contaminating tumor cells from autologous bone marrow.

  15. Optimising the therapeutic ratio of radioimmunotherapy; an investigation of the roles of chimerisation, fractionation and radiation dosimetry

    NASA Astrophysics Data System (ADS)

    Violet, John Albert

    2007-12-01

    Radioimmunotherapy (RIT) is a targeted form of treatment for cancer which uses tumour-associated antibodies to selectively deliver a therapeutic radionuclide to sites of disease. In lymphoma, radioimmunotherapy has proved a remarkably effective agent due to the high radiosensitivity of the tumour and its propensity to undergo apoptosis following irradiation. However, success in the treatment of the more radioresistant common solid tumours has been less successful, and for these patients RIT remains investigative. The effectiveness of RIT is limited by non-specific irradiation of normal tissues whilst antibody remains in the circulation, in particular bone marrow, and also by immunogenicity of antibody which does not allow for repeated therapy. In the first chapter I have hypothesised that lymphomas expressing the interleukin-2 receptor might be effectively treated using a radiolabeled antibody to this receptor. In a phase I/II clinical study, 131I labelled CHT-25, a chimeric antibody against the IL-2Ra chain, has shown encouraging evidence of efficacy in the 9 patients with multiply- relapsed lymphomas treated so far. In addition, use of this antibody has been associated with low immunogenicity allowing for repeated therapies to be given. In the second chapter I have hypothesised that dosimetry led, individual patient therapy, might further optimise 1311 CHT-25 treatment. To investigate this I have used marrow toxicity as a biological assay of absorbed dose and shown that simple, but individual, patient biodistribution indices correlate better with observed toxicity than the population-based dose estimates currently employed. I have proposed that adoption of individual patient dosimetry using tracer studies is worthy of further investigation for the future development of 131I- CHT-25. In the third chapter I have hypothesised that dose fractionation might improve the therapeutic ratio of RIT. This has been investigated in a pre-clinical human colorectal xenograft

  16. Heme oxygenase-1 deficiency alters erythroblastic island formation, steady-state erythropoiesis and red blood cell lifespan in mice

    PubMed Central

    Fraser, Stuart T.; Midwinter, Robyn G.; Coupland, Lucy A.; Kong, Stephanie; Berger, Birgit S.; Yeo, Jia Hao; Andrade, Osvaldo Cooley; Cromer, Deborah; Suarna, Cacang; Lam, Magda; Maghzal, Ghassan J.; Chong, Beng H.; Parish, Christopher R.; Stocker, Roland

    2015-01-01

    Heme oxygenase-1 is critical for iron recycling during red blood cell turnover, whereas its impact on steady-state erythropoiesis and red blood cell lifespan is not known. We show here that in 8- to 14-week old mice, heme oxygenase-1 deficiency adversely affects steady-state erythropoiesis in the bone marrow. This is manifested by a decrease in Ter-119+-erythroid cells, abnormal adhesion molecule expression on macrophages and erythroid cells, and a greatly diminished ability to form erythroblastic islands. Compared with wild-type animals, red blood cell size and hemoglobin content are decreased, while the number of circulating red blood cells is increased in heme oxygenase-1 deficient mice, overall leading to microcytic anemia. Heme oxygenase-1 deficiency increases oxidative stress in circulating red blood cells and greatly decreases the frequency of macrophages expressing the phosphatidylserine receptor Tim4 in bone marrow, spleen and liver. Heme oxygenase-1 deficiency increases spleen weight and Ter119+-erythroid cells in the spleen, although α4β1-integrin expression by these cells and splenic macrophages positive for vascular cell adhesion molecule 1 are both decreased. Red blood cell lifespan is prolonged in heme oxygenase-1 deficient mice compared with wild-type mice. Our findings suggest that while macrophages and relevant receptors required for red blood cell formation and removal are substantially depleted in heme oxygenase-1 deficient mice, the extent of anemia in these mice may be ameliorated by the prolonged lifespan of their oxidatively stressed erythrocytes. PMID:25682599

  17. Reviving red snapper.

    PubMed

    Estabrook, Barry

    2010-01-01

    Red snappers in the Gulf of Mexico once hovered on the brink of extinction, their population having dropped to 2 percent of what had historically swum in the Gulf. But thanks to a recently introduced plan that turns the conventional wisdom of fisheries management on its head, the picture has begun to change. Called Individual Fishing Quotas (IFQs), the new regulations, which give a guaranteed allotment of fish to each participant instead of applying industry-wide quotas, went into effect for Gulf of Mexico Red Snapper (Lutjanus campechanus) in early 2007. The results were immediate and so profound that the Gulf Fishery Management Council voted earlier this year to increase the annual limit on red snapper to nearly 7 million pounds from 5 million. PMID:21542214

  18. Red-based cumulus.

    PubMed

    Gedzelman, Stanley David

    2015-02-01

    Observations and model simulations of cumulus clouds whose bases are tinted red when the Sun is well above the horizon are presented. Conditions for seeing red bases include (1) a red underlying surface (which may consist of dust clouds, as from haboobs) with high albedo, (2) small fractional cloud cover when the Sun is far enough below the zenith for direct sunlight to illuminate much of the surface directly below and around cloud base, (3) optically thick clouds so that the bases are dark, and (4) clouds with bases that are near enough to the observer to appear high in the sky so that the admixture of scattered light from the intervening atmosphere is minimized. PMID:25967822

  19. The study of indicators of bone marrow and peripheral blood of rats with diabetes and transplanted liver tumor after intravenous injection of gold nanorods

    NASA Astrophysics Data System (ADS)

    Dikht, Nataliya I.; Bucharskaya, Alla B.; Maslyakova, Galina N.; Terentyuk, Georgy S.; Matveeva, Olga V.; Navolokin, Nikita A.; Khlebtsov, Boris N.; Khlebtsov, Nikolai G.

    2015-03-01

    In study the evaluation of the influence of gold nanorods on morphological indicators of red bone marrow and peripheral blood of rats with diabetes and transplanted liver tumor after intravenous administration of gold nanorods was conducted. We used gold nanorods with length 41 ± 8 nm and diameter of 10.2±2 nm, synthesized in the laboratory of nanobiotechnology IBPPM RAS (Saratov). After intravenous administration of gold nanorods the decrease of leukocytes, platelets and lymphocytes was observed in animals of control group in blood. It was marked the decrease of the number of mature cellular elements of the leukocyte germ in bone marrow - stab neutrophils and segmented leukocytes, and the increase of immature elements- metamyelocytes, indicating the activation of leukocyte germ after nanoparticle administration. The decrease of leukocyte amount was noted in blood and the increase of cellular elements of the leukocyte germ was revealed in bone marrow, indicating the activation of leukocyte germ in rats with alloxan diabetes and transplanted tumors. The changes of morphological indicators of blood and bone marrow testify about stimulation of myelocytic sprouts of hemopoiesis in bone marrow as a result of reduction of mature cells in peripheral blood after gold nanoparticle administration.

  20. Quantitative 3D Optical Imaging: Applications in Dosimetry and Biophysics

    NASA Astrophysics Data System (ADS)

    Thomas, Andrew Stephen

    Optical-CT has been shown to be a potentially useful imaging tool for the two very different spheres of biologists and radiation therapy physicists, but it has yet to live up to that potential. In radiation therapy, researchers have used optical-CT for the readout of 3D dosimeters, but it is yet to be a clinically relevant tool as the technology is too slow to be considered practical. Biologists have used the technique for structural imaging, but have struggled with emission tomography as the reality of photon attenuation for both excitation and emission have made the images quantitatively irrelevant. Dosimetry. The DLOS (Duke Large field of view Optical-CT Scanner) was designed and constructed to make 3D dosimetry utilizing optical-CT a fast and practical tool while maintaining the accuracy of readout of the previous, slower readout technologies. Upon construction/optimization/implementation of several components including a diffuser, band pass filter, registration mount & fluid filtration system the dosimetry system provides high quality data comparable to or exceeding that of commercial products. In addition, a stray light correction algorithm was tested and implemented. The DLOS in combination with the 3D dosimeter it was designed for, PREAGETM, then underwent rigorous commissioning and benchmarking tests validating its performance against gold standard data including a set of 6 irradiations. DLOS commissioning tests resulted in sub-mm isotropic spatial resolution (MTF >0.5 for frequencies of 1.5lp/mm) and a dynamic range of ˜60dB. Flood field uniformity was 10% and stable after 45minutes. Stray light proved to be small, due to telecentricity, but even the residual can be removed through deconvolution. Benchmarking tests showed the mean 3D passing gamma rate (3%, 3mm, 5% dose threshold) over the 6 benchmark data sets was 97.3% +/- 0.6% (range 96%-98%) scans totaling ˜10 minutes, indicating excellent ability to perform 3D dosimetry while improving the speed of

  1. Targeted Pathologic Evaluation of Bone Marrow Donors Identifies Previously Undiagnosed Marrow Abnormalities

    PubMed Central

    Tilson, MP; Jones, RJ; Sexauer, A; Griffin, CA; Morsberger, LA; Batista, DAS; Small, D; Burns, KH; Gocke, CD; Vuica-Ross, M; Borowitz, MJ; Duffield, AS

    2013-01-01

    Potential bone marrow donors are screened to ensure the safety of both the donor and recipient. At our institution, potential donors with abnormal peripheral blood cell counts, a personal history of malignancy, or age >60 years are evaluated to ensure that they are viable candidates for donation. Evaluation of the marrow includes morphologic, flow cytometric and cytogenetic studies. 122 potential donors were screened between the years of 2001–2011, encompassing approximately 10% of all donors. The median age of the screened potential donors was 59 years, and included 59 men and 63 women. The donors were screened because of age >60 years old (33), anemia (22), cytopenias other than anemia (27), elevated peripheral blood counts without a concurrent cytopenia (20), elevated peripheral blood counts with a concurrent cytopenia (10), history of malignancy (4), abnormal peripheral blood differential (3), prior graft failure (1), history of treatment with chemotherapy (1), and body habitus (1). Marrow abnormalities were detected in 9% (11/122) of donors. These donors were screened because of anemia (5/22; 23%), age >60 years (2/33; 6%), history of malignancy (2/4; 50%), elevated peripheral blood counts (1/20; 5%), and body habitus (1/1; 100%). Abnormalities included plasma cell dyscrasia (3), abnormal marrow cellularity (3), clonal cytogenetic abnormalities (2), low-grade myelodysplastic syndrome (1), a mutated JAK2 V617F allele (1), and monoclonal B-cell lymphocytosis (1). Our experience indicates that extended screening of potential donors identifies a significant number of donors with previously undiagnosed marrow abnormalities. PMID:23769818

  2. Lustre on Red Sky.

    SciTech Connect

    Monk, Stephen Todd; Mervini, Joe

    2010-04-01

    The goals of Lustre on Red Sky are: (1) provide home/projects/scratch Lustre file systems; (2) adhere to the Sun HPC stack; (3) implement software RAID on Sun provided JBODs; and (4) design for easy administration. Conclusions are: (1) software RAID includes additional risks and administration vs. hardware RAID solutions; (2) limited testing of hardware in these configurations make it ill-suited for rapid deployment in a production environment; and (3) Lustre has been a shining star on this machine, Red Sky users are pleased with its performance.

  3. Proliferative and Glycolytic Assessment of the Whole-Body Bone Marrow Compartment

    PubMed Central

    Goryawala, Mohammed; Adjoua, Malek; Güleç, Seza

    2015-01-01

    Objective: Quantitative assessment of active bone marrow (BM) in vivo is yet to be well-defined. This study aims to compare total body BM volume estimations obtained from use of both18F-FLT PET/CT and 18F-FDG PET/CT in order to consolidate higher cellular proliferation rates with imaging the highly active red BM in pancreatic cancer. Methods: This phase I pilot study includes seven patients with pancreatic cancers who underwent both 18F-FLT and 18F-FDG imaging each acquired within a week’s duration. A CT-based classifier is used for segmenting bone into cortical and trabecular regions. The total BM volume is determined through statistical thresholding on PET activity found within the trabecular bone. Results: Results showed that 18F-FLT measures of red BM volume (RBV) were higher than those obtained from 18F-FDG (∆=89.21 ml). RBV obtained using 18F-FLT in males were found to have high correlation with measured weight (R2=0.61) and BMI (R2=0.70). The red BM fraction obtained from 18F-FLT was significantly different between males and females, with females showing much higher red bone matter within the trabecular bone (p<0.05). In contrast to 18F-FLT, 18F-FDG BM measurements showed that RBV was significantly different between males and females (p<0.05). Results also show that spinal activity SUV threshold for red BM segmentation is significantly different between 18F-FLT PET and 18F-FDG PET (p<0.05). Conclusion: By combining 18F-FLT-PET and 18F-FDG-PET, this study provides useful insights for in vivo BM estimation through its proliferative and glycolytic activities. PMID:26316472

  4. Permanent Breast Seed Implant Dosimetry Quality Assurance

    SciTech Connect

    Keller, Brian M.; Ravi, Ananth; Sankreacha, Raxa; Pignol, Jean-Philippe

    2012-05-01

    Purpose: A permanent breast seed implant is a novel method of accelerated partial breast irradiation for women with early-stage breast cancer. This article presents pre- and post-implant dosimetric data, relates these data to clinical outcomes, and makes recommendations for those interested in starting a program. Methods and Materials: A total of 95 consecutive patients were accrued into one of three clinical trials after breast-conserving surgery: a Phase I/II trial (67 patients with infiltrating ductal carcinoma); a Phase II registry trial (25 patients with infiltrating ductal carcinoma); or a multi-center Phase II trial for patients with ductal carcinoma in situ (3 patients). Contouring of the planning target volume (PTV) was done on a Pinnacle workstation and dosimetry calculations, including dose-volume histograms, were done using a Variseed planning computer. Results: The mean pre-implant PTV coverage for the V{sub 90}, V{sub 100}, V{sub 150}, and V{sub 200} were as follows: 98.8% {+-} 1.2% (range, 94.5-100%); 97.3% {+-} 2.1% (range, 90.3-99.9%), 68.8% {+-} 14.3% (range, 32.7-91.5%); and 27.8% {+-} 8.6% (range, 15.1-62.3%). The effect of seed motion was characterized by post-implant dosimetry performed immediately after the implantation (same day) and at 2 months after the implantation. The mean V{sub 100} changed from 85.6% to 88.4% (p = 0.004) and the mean V{sub 200} changed from 36.2% to 48.3% (p < 0.001). Skin toxicity was associated with maximum skin dose (p = 0.014). Conclusions: Preplanning dosimetry should aim for a V{sub 90} of approximately 100%, a V{sub 100} between 95% and 100%, and a V{sub 200} between 20% and 30%, as these numbers are associated with no local recurrences to date and good patient tolerance. In general, the target volume coverage improved over the duration of the seed therapy. The maximum skin dose, defined as the average dose over the hottest 1 Multiplication-Sign 1-cm{sup 2} surface area, should be limited to 90% of the

  5. Comparison of Real-Time Intraoperative Ultrasound-Based Dosimetry With Postoperative Computed Tomography-Based Dosimetry for Prostate Brachytherapy

    SciTech Connect

    Nag, Subir; Shi Peipei; Liu Bingren; Gupta, Nilendu; Bahnson, Robert R.; Wang, Jian Z.

    2008-01-01

    Purpose: To evaluate whether real-time intraoperative ultrasound (US)-based dosimetry can replace conventional postoperative computed tomography (CT)-based dosimetry in prostate brachytherapy. Methods and Materials: Between December 2001 and November 2002, 82 patients underwent {sup 103}Pd prostate brachytherapy. An interplant treatment planning system was used for real-time intraoperative transrectal US-guided treatment planning. The dose distribution was updated according to the estimated seed position to obtain the dose-volume histograms. Postoperative CT-based dosimetry was performed a few hours later using the Theraplan-Plus treatment planning system. The dosimetric parameters obtained from the two imaging modalities were compared. Results: The results of this study revealed correlations between the US- and CT-based dosimetry. However, large variations were found in the implant-quality parameters of the two modalities, including the doses covering 100%, 90%, and 80% of the prostate volume and prostate volumes covered by 100%, 150%, and 200% of the prescription dose. The mean relative difference was 38% and 16% for doses covering 100% and 90% of the prostate volume and 10% and 21% for prostate volumes covered by 100% and 150% of the prescription dose, respectively. The CT-based volume covered by 200% of the prescription dose was about 30% greater than the US-based one. Compared with CT-based dosimetry, US-based dosimetry significantly underestimated the dose to normal organs, especially for the rectum. The average US-based maximal dose and volume covered by 100% of the prescription dose for the rectum was 72 Gy and 0.01 cm{sup 3}, respectively, much lower than the 159 Gy and 0.65 cm{sup 3} obtained using CT-based dosimetry. Conclusion: Although dosimetry using intraoperative US-based planning provides preliminary real-time information, it does not accurately reflect the postoperative CT-based dosimetry. Until studies have determined whether US-based dosimetry

  6. Evaluation of dose homogenization and radiation carcinogenesis risk in total body irradiation for bone marrow transplantation.

    PubMed

    Oysul, K; Dirican, B; Beyzadeoglu, M; Sürenkok, S; Arpaci, F; Pak, Y

    2003-01-01

    The purpose of this study is to report on the dose homogeneity in total body irradiated patients undergoing Bone Marrow Transplantation (BMT), and carcinogenic risk in surviving patients. Between 1987 and 2001, 105 patients received hyperfractionated (6 fractions in 3 days) 12 Gy Total Body Irradiation (TBI) in our institution with lateral opposed fields. All the patients had measurements with thermoluminiscence dosimetry (TLD100) placed on seven bilateral body sites in vivo, controlled by the randophantom measurements to verify reasonable dose homogeneity achievement. The comorbid effects in the whole TBI conditioning group with at least three months post BMT follow-up were noted and surviving patients who had a minimum 5-year and maximum 14-year follow-up (median 7.8 years) have been evaluated for carcinogenic radiation risk on the basis of tissue weighting factors as defined by ICRP 60. Reasonable dose homogeneity by lateral opposed beam TBI has been obtained in all 105 patients in whom lateral TLD100 measurement means were within +5% of the planned doses. Calculated carcinogenesis risk factor was 11.34% for males and 12.40% for females, and no second-cancer has been detected whilst radiation-induced 5 cataracts and 10 interstitial pneumonia comorbidities were noted. Dose homogenization can be well achieved for hyperfractionated lateral-beam TBI with acceptable comorbidities and estimated second-cancer risk is significant but relatively low compared to the risk from the clinical indications for TBI. PMID:14628091

  7. Yttrium-90/indium-111 DOTA peptide chimeric L6; pharmacokinetics, dosimetry and initial therapeutic studies in patients with breast cancer

    SciTech Connect

    DeNardo, S.J.; Shen, S.; Richman, C.M.

    1995-05-01

    Chimeric L6 MoAb(ChL6) as I-131 ChL6 has shown therapeutic promise in breast cancer patients. To enhance this potential, we developed yttrium-90 (Y-90) and indium-111 (In-111) ChL6 radiopharmaceuticals by conjugating Y-90 and In-111 DOTA peptide ChL6. Immunoreactivity of In-111 and Y-90 ChL6 was 80-100% of ChL6. Dosimetry was calculated from pharmacokinetics obtained in four studies of patients with metastatic breast cancer using 200 mg ChL6 and 4mCi In-111/3mCi Y-90 DOTA peptide ChL6 in 3 studies and 10 mCi In-111 in one (specific activity 1.1-3.5mCi/mg). Quantitative imaging of In-111 and in vitro analysis of Y-90/In-111 blood and urine clearances and biopsies for bone and marrow uptake were performed. In-111 and Y-90 DOTA peptide ChL6 blood clearances were compared in each patient with {beta} intercepts for each initial study of 13.9/12.7, 4.9/5.8, 25.2/16.2 (%ID), and {beta} T{1/2} 32/30, 33/35, and 41/57 (h) for In- 111/Y-90, respectively. Normal organ and tumor dosimetry for Y-90 DOTA peptide ChL6 was extrapolated from the In-111 kinetics: WB 2.1-2.3, Liver 3.8-5.9, Lung 6.2-7.9, Kidney 8.1-11.3, Spleen 4.4-14.0 (cGy/mCi). Dosimetry of 13 tumored areas (1-10 g) ranged from 42-260 (mean = 103) cGy/mCi. Marrow doses calculated from Y-90 in blood ranged from 0.6-1.5. Marrow biopsies at 5 d pi showed In-111 and Y-90 (%ID/g), 1-2 x 10{sup -3} and 6-7x10{sup -4} and bone 1-3x10{sup -3} and 0.1-3x10{sup -4}, respectively. Compared to our previous I-131 ChL6 dosimetry, this study indicates that the Y-90 DOTA peptide ChL6 radiation dose to tumor is 4-8 times that of I-131 ChL6 whereas normal organs receive less than twice that of I-131 from Y-90. Based on this calculated enhancement of the therapeutic ratio, a multicycle Y-90 DOTA peptide ChL6 therapy protocol has been initiated in breast cancer patients.

  8. The biodistribution and dosimetry of {sup 117m}Sn DTPA with special emphasis on active marrow absorbed doses

    SciTech Connect

    Stubbs, J.; Atkins, H.

    1999-01-01

    {sup 117m}Sn(4+) DTPA is a new radiopharmaceutical for the palliation of pain associated with metastatic bone cancer. Recently, the Phase 2 clinical trials involving 47 patients were completed. These patients received administered activities in the range 6.7--10.6 MBq/kg of body mass. Frequent collections of urine were acquired over the first several hours postadministration and daily cumulative collections were obtained for the next 4--10 days. Anterior/posterior gamma camera images were obtained frequently over the initial 10 days. Radiation dose estimates were calculated for 8 of these patients. Each patient`s biodistribution data were mathematically simulated using a multicompartmental model. The model consisted of the following compartments: central, bone, kidney, other tissues, and cumulative urine. The measured cumulative urine data were used as references for the cumulative urine excretion compartment. The total-body compartment (sum of the bone surfaces, central, kidney, and other tissues compartments) was reference to all activity not excreted in the urine.

  9. Gamma-ray dosimetry measurements of the Little Boy replica

    SciTech Connect

    Plassmann, E.A.; Pederson, R.A.

    1984-01-01

    We present the current status of our gamma-ray dosimetry results for the Little Boy replica. Both Geiger-Mueller and thermoluminescent detectors were used in the measurements. Future work is needed to test assumptions made in data analysis.

  10. Proceedings of the third conference on radiation protection and dosimetry

    SciTech Connect

    Swaja, R.E.; Sims, C.S.; Casson, W.H.

    1991-10-01

    The Third Conference on Radiation Protection and Dosimetry was held during October 21--24, 1991, at the Sheraton Plaza Hotel in Orlando, Florida. This meeting was designed with the objectives of promoting communication among applied, research, regulatory, and standards personnel involved in radiation protection, and providing them with sufficient information to evaluate their programs. To meet these objectives, a technical program consisting of more than 75 invited and contributed oral presentations encompassing all aspects of radiation protection was prepared. General topics considered in the technical session included external dosimetry, internal dosimetry, instruments, accident dosimetry, regulations and standards, research advances, and applied program experience. In addition, special sessions were held to afford attendees the opportunity to make short presentations of recent work or to discuss topics of general interest. Individual reports are processed separately on the database.

  11. MECHANISTIC DOSIMETRY MODELS OF NANOMATERIAL DEPOSITION IN THE RESPIRATORY TRACT

    EPA Science Inventory

    Accurate health risk assessments of inhalation exposure to nanomaterials will require dosimetry models that account for interspecies differences in dose delivered to the respiratory tract. Mechanistic models offer the advantage to interspecies extrapolation that physicochemica...

  12. Radiation dosimetry for quality control of food preservation and disinfestation

    NASA Astrophysics Data System (ADS)

    McLaughlin, W. L.; Miller, A.; Uribe, R. M.

    In the use of x and gamma rays and scanned electron beams to extend the shelf life of food by delay of sprouting and ripening, killing of microbes, and control of insect population, quality assurance is provided by standardized radiation dosimetry. By strategic placement of calibrated dosimeters that are sufficiently stable and reproducible, it is possible to monitor minimum and maximum radiation absorbed dose levels and dose uniformity for a given processed foodstuff. The dosimetry procedure is especially important in the commisioning of a process and in making adjustments of process parameters (e.g. conveyor speed) to meet changes that occur in product and source parameters (e.g. bulk density and radiation spectrum). Routine dosimetry methods and certain corrections of dosimetry data may be selected for the radiations used in typical food processes.

  13. Retrospective dosimetry analyses of reactor vessel cladding samples

    SciTech Connect

    Greenwood, L. R.; Soderquist, C. Z.; Fero, A. H.

    2011-07-01

    Reactor pressure vessel cladding samples for Ringhals Units 3 and 4 in Sweden were analyzed using retrospective reactor dosimetry techniques. The objective was to provide the best estimates of the neutron fluence for comparison with neutron transport calculations. A total of 51 stainless steel samples consisting of chips weighing approximately 100 to 200 mg were removed from selected locations around the pressure vessel and were sent to Pacific Northwest National Laboratory for analysis. The samples were fully characterized and analyzed for radioactive isotopes, with special interest in the presence of Nb-93m. The RPV cladding retrospective dosimetry results will be combined with a re-evaluation of the surveillance capsule dosimetry and with ex-vessel neutron dosimetry results to form a comprehensive 3D comparison of measurements to calculations performed with 3D deterministic transport code. (authors)

  14. Dosimetry of ozone and nitrogen dioxide in man and animals

    SciTech Connect

    Overton, J.H. Jr.; Miller, F.J.

    1984-01-01

    The health effects of ozone (O/sub 3/) and nitrogen dioxide (NO/sub 2/) are assessed from animal toxicological, controlled human, and epidemiological studies. These assessments will be strengthened when results of animal studies can be quantitatively extrapolated to man. To achieve quantitative extrapolation, improvements are needed in the areas of dosimetry and species sensitivity. And, of course, an adequate health effect data base must exist on which to make extrapolations. The focus of this paper is to review the regional dosimetry of O/sub 3/ and NO/sub 2/ in the respiratory tract of man and animals. Dosimetry relates to estimating the amount of pollutant reaching a specific target region of the respiratory tract as a function of exposure concentration. At present, there are two approaches to dosimetry, experimental and mathematical modeling, which are discussed.

  15. National Marrow Donor Program and Be The Match Registry

    MedlinePlus

    ... version of this page please turn Javascript on. Feature: Bone Marrow Transplants The National Marrow Donor Program and Be The Match Registry Past Issues / Summer 2011 Table of Contents Creating connections. Saving lives. Founded in 1987 by the federal government, the ...

  16. Investigation criteria for dosimetry results comparisons

    SciTech Connect

    Hough, E.G. )

    1984-01-01

    This paper reports that the Oconee Nuclear Station, like most nuclear facilities, monitors its personnel with two types of dosimeters: a thermoluminescent dosimeter (TLD), which is normally used for determining the official dose equivalent, and a pocket ionization chamber (PIC), which is used to estimate exposure for control purposes. At Oconee, the results obtained from the two types of dosimeters are compared on a monthly basis as a part of the routine exchange and processing of worker TLDs. Each worker's TLD result is compared to the sum of the PIC dose estimates for the month that the TLD was used. The TLD result is accepted as the official dose equivalent for the month if the comparison results are within the tolerance limits specified by the criteria. An out-of-tolerance comparison requires investigation, which consists of performance tests of the dosimetry involved and reviews of exposure records. Adjustments to a worker's official dose equivalent are made when warranted by an investigation.

  17. Gastroesophageal scintiscanning in a pediatric population: dosimetry

    SciTech Connect

    Castronovo, F.P. Jr.

    1986-07-01

    The dosimetry associated with orally administered (/sup 99m/Tc)sulfur colloid for the diagnosis of gastroesophageal reflux has not been adequately described for the pediatric populations. Standard MIRD methodology was performed for the following: newborn, 1, 5, 10, and 15 yr old, and adult standard man. The critical organ for all pediatric groups was the lower large intestine with absorbed dose of 0.927, 0.380, 0.194, 0.120 and 0.0721 rad/100 microCi, respectively. For the adult the critical organ was the upper large intestine with an absorbed dose of 0.0518 rad/100 microCi. These data should be considered when administering (99mTc)sulfur colloid orally in a pediatric population.

  18. Advanced Semiconductor Dosimetry in Radiation Therapy

    SciTech Connect

    Rosenfeld, Anatoly B.

    2011-05-05

    Modern radiation therapy is very conformal, resulting in a complexity of delivery that leads to many small radiation fields with steep dose gradients, increasing error probability. Quality assurance in delivery of such radiation fields is paramount and requires real time and high spatial resolution dosimetry. Semiconductor radiation detectors due to their small size, ability to operate in passive and active modes and easy real time multichannel readout satisfy many aspects of in vivo and in a phantom quality assurance in modern radiation therapy. Update on the recent developments and improvements in semiconductor radiation detectors and their application for quality assurance in radiation therapy, based mostly on the developments at the Centre for Medical Radiation Physics (CMRP), University of Wollongong, is presented.

  19. Dosimetry in mixed neutron-gamma fields

    SciTech Connect

    Remec, I.

    1998-04-01

    The gamma field accompanying neutrons may, in certain circumstances, play an important role in the analysis of neutron dosimetry and even in the interpretation of radiation induced steel embrittlement. At the High Flux Isotope Reactor pressure vessel the gamma induced reactions dominate the responses of {sup 237}Np and {sup 238}U dosimeters, and {sup 9}Be helium accumulation fluence monitors. The gamma induced atom displacement rate in steel is higher than corresponding neutron rate, and is the cause of ``accelerated embrittlement`` of HFIR materials. In a large body of water, adjacent to a fission plate, photofissions contribute significantly to the responses of fission monitors and need to be taken into account if the measurements are used for the qualification of the transport codes and cross-section libraries.

  20. AMS applied to Hiroshima and Chernobyl dosimetry

    SciTech Connect

    Straume, T.; Marchetti, A.A.; Anspaugh, L.R.

    1995-12-01

    Two projects employing AMS are summarized and updated. One project employs AMS to measure {sup 36}Cl in concrete and other mineral samples from Hiroshima and Nagasaki to help reconstruct neutron fluences received by the atom-bomb survivors. In this project, we have demonstrated a large discrepancy between the neutron activation measured in Hiroshima and predictions based on the current dosimetry system. This discrepancy has practical implications for radiation risk assessment and radiation protection standards. The other project employs AMS to measure {sup 129}I in soil and other environmental samples from Belarus, Ukraine, and Russia. This is a proof-of-principle study to determine if the long lived {sup 129}I isotope (half life, 16 x 10{sup 6} y) measured by AMS can be used to reconstruct deposition of the short lived {sup 131}I isotope from the 1986 Chernobyl reactor accident. This is required because {sup 131}I disappeared before adequate measurements could be made.

  1. Simultaneous macro and micro dosimetry with MOSFETs

    SciTech Connect

    Rosenfeld, A.B.; Kaplan, G.I.; Carolan, M.G.; Allen, B.J.; Maughan, R.; Yudelev, M.; Kota, C.; Coderre, J.

    1996-12-01

    The application of MOSFET dosimeters in complicated mixed radiation fields for measurement of absorbed dose distribution in tissue equivalent phantoms has been studied. The spectra of secondary charged particles have been measured simultaneously with average absorbed doses by the same MOSFET dosimeter. A good correlation has been observed between neutron depth dose distribution in a water phantom obtained using MOSFETs in integral mode and a tissue equivalent (T.E.) ionization chamber. Such MOSFET dosimeters are a promising tool for micro-macro dosimetry in Boron Neutron Capture Therapy (BNCT) and Fast Neutron Therapy (FNT). Paired MOSFETs with one of the dosimeters covered by {sup 10}B have been applied for measuring of average boron dose distribution and microdosimetric spectra due to alpha particles and {sup 7}Li ions throughout a perspex phantom exposed in the epithermal neutron beam at the Brookhaven Medical Research Reactor (BMRR).

  2. Dosimetry for photodynamic therapy of endometrial tissue

    NASA Astrophysics Data System (ADS)

    Svaasand, Lars O.; Fehr, Mathias K.; Madsen, Sten; Tadir, Yona; Tromberg, Bruce J.

    1995-05-01

    Hysterectomy is the most common major operation performed in the United States with dysfunctional uterine bleeding as one of the major indications. The clinical needs for simple and safe endometrial destruction are essential. Photodynamic therapy (PDT) may offer a simple and cost effective solution for the treatment of dysfunctional uterine bleeding. The dosimetry is discussed for the case of topical application of photosensitizer. This technique might be the method of preference because undesired side effects such as skin photosensitization that is typical for systemically injected photosensitizers, can be avoided. Effective PDT requires a sufficient amount of light delivered to the targeted tissue in a reasonable period of time. A trifurcated optical applicator consisting of three cylindrical diffusing fibers has been constructed, and this applicator can deliver a typical required optical dose of about 50-100 J/cm2 to the full depth of the endometrium for an exposure time of 10-20 minutes.

  3. Tissue substitutes in radiation dosimetry and measurement

    SciTech Connect

    Not Available

    1989-01-01

    This book explains the activities of the International Commission on Radiation Units and Measurements and discusses tissue substitutes in radiation dosimetry and measurement. The following section is on basic concepts including definitions, specifications, and interaction coefficients. This section also includes a description of the effects of photons, electrons, neutrons, and heavily charged particles on body tissues. The third section is on selected requirements for tissue substitutes and briefly covers radiation-related requirements for radiation therapy, radiologic diagnosis, radiation protection, and radiobiology. The fourth short section is on composition of body tissues, and comparative interaction and depth dose data for selected tissue substitutes are covered in the fifth section. This includes several tables and many graphs of the ratios required to calculate the radiation dose.

  4. Immunotactoid glomerulopathy with massive bone marrow deposits in a patient with IgM kappa monoclonal gammopathy and hypocomplementemia.

    PubMed

    Da'as, N; Kleinman, Y; Polliack, A; Amir, G; Ne'eman, Z; Kopolovic, J; Bits, H; Darmon, D

    2001-08-01

    A case of immunotactoid glomerulopathy with an amyloid-like material in the glomeruli and bone marrow is described. Clinically the patient was diagnosed as having severe nephrotic syndrome, hypocomplementemia, and IgM kappa monoclonal gammopathy. Immunotactoid glomerulopathy is an unusual cause of glomerulonephritis, characterized by Congo red-negative, amyloid-like deposits in the glomeruli. This unusual case presentation shows that immunotactoid glomerulopathy may be a manifestation of systemic disease. This patient also presented with hypocomplementemia, an extremely rare associated finding that has been reported previously in only four cases of immunotactoid glomerulopathy. PMID:11479168

  5. Clover, Red (Trifolium pretense)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Genetic modification of plants by the insertion of transgenes can be a powerful experimental approach to answer basic questions about gene product function. This technology can also be used to make improved crop varieties for use in the field. To apply this powerful tool to red clover, an important ...

  6. 'Valley Red' Strawberry

    Technology Transfer Automated Retrieval System (TEKTRAN)

    'Valley Red' is a new June-bearing (short-day) strawberry (Fragaria ×ananassa Duchesne ex Rozier) cultivar from the U.S. Department of Agriculture-Agricultural Research Service (USDA-ARS) breeding program in Corvallis, Ore., released in cooperation with the Oregon Agricultural Experiment Station, Th...

  7. 'Vintage' Red Raspberry

    Technology Transfer Automated Retrieval System (TEKTRAN)

    'Vintage' is a new primocane-fruiting red raspberry (Rubus idaeus L.) from the U.S. Dept. of Agriculture–Agricultural Research Service (USDA–ARS) breeding program in Corvallis, OR released in cooperation with the Oregon State Agricultural Experiment Station and the Washington State University Agricu...

  8. Red Cross Swimming Update.

    ERIC Educational Resources Information Center

    Vlasich, Cynthia

    1989-01-01

    Six new aquatic courses, developed by the Red Cross, are described. They are: Infant and Preschool Aquatics, Longfellow's Whale Tales (classroom water safety lessons for K-Six), Basic Water Safety, Emergency Water Safety, Lifeguard Training, and Safety Training for Swim Coaches. (IAH)

  9. Red Emitting VCSEL

    NASA Astrophysics Data System (ADS)

    Jetter, Michael; Roßbach, Robert; Michler, Peter

    This chapter describes the progress in development of vertical-cavity surface-emitting lasers (VCSEL) emitting in the red spectral region around 650 nm for data transmission over polymer optical fibers (POF). First, growth issues of red VCSEL using two different material systems, namely AlGaAs and AlGaInP, are introduced. In particular, the optical and electrical state-of-the-art characteristics as low threshold currents ({≤} 1 mA) and high output powers (several mW) are presented with a special focus on emission wavelength. Also the thermal budget and heat removal in the devices are pointed out with regard to the geometry of the VCSEL. Small-signal modulation response in terms of maximum resonance frequency in dependance on temperature behavior are discussed. Applications of these devices in optical interconnects are described and digital data transmission at data rates up to 2.1 Gbit/s over step-index POF is reported. These properties make red emitting VCSEL perfectly suited for high-speed low power consuming light sources for optical data communication via POF. By introducing InP quantum dots as gain material in red emitting VCSEL nearly temperature independent record low threshold current densities of around 10 A/cm2 could be observed.

  10. 'Saanich' Red Raspberry

    Technology Transfer Automated Retrieval System (TEKTRAN)

    'Saanich' is a new floricane-fruiting red raspberry (Rubus idaeus) cultivar from the breeding program at the Pacific Agri-Food Research Centre (PARC) of Agriculture and Agri-Food Canada, Agassiz, British Columbia. 'Saanich', tested as BC 89-34-41, was selected from a 1989 cross of BC 82-5-161 and BC...

  11. Canadian Red Cross.

    PubMed

    Lavender, Colleen

    2008-01-01

    The Canadian Red Cross is guided by its Fundamental Principles--humanity, impartiality, neutrality, independence, voluntary service, unity, and universality--and organized in a traditional geographic hierarchical structure. Among the characteristics that have contributed to its success are a budgeting process that starts at the local level, measurement of program outcomes, and coordinated fundraising activities at the regional level. PMID:18551842

  12. Neutron dosimetry in boron neutron capture therapy

    SciTech Connect

    Fairchild, R.G.; Miola, U.J.; Ettinger, K.V.

    1981-01-01

    The recent development of various borated compounds and the utilization of one of these (Na/sub 2/B/sub 12/H/sub 11/SH) to treat brain tumors in clinical studies in Japan has renewed interest in neutron capture therapy. In these procedures thermal neutrons interact with /sup 10/B in boron containing cells through the /sup 10/B(n,..cap alpha..)/sup 7/Li reaction producing charged particles with a maximum range of approx. 10..mu..m in tissue. Borated analogs of chlorpromazine, porphyrin, thiouracil and deoxyuridine promise improved tumor uptake and blood clearance. The therapy beam from the Medical Research Reactor in Brookhaven contains neutrons from a modified and filtered fission spectrum and dosimetric consequences of the use of the above mentioned compounds in conjunction with thermal and epithermal fluxes are discussed in the paper. One of the important problems of radiation dosimetry in capture therapy is determination of the flux profile and, hence, the dose profile in the brain. This has been achieved by constructing a brain phantom made of TE plastic. The lyoluminescence technique provides a convenient way of monitoring the neutron flux distributions; the detectors for this purpose utilize /sup 6/Li and /sup 10/B compounds. Such compounds have been synthesized specially for the purpose of dosimetry of thermal and epithermal beams. In addition, standard lyoluminescent phosphors, like glutamine, could be used to determine the collisional component of the dose as well as the contribution of the /sup 14/N(n,p)/sup 14/C reaction. Measurements of thermal flux were compared with calculations and with measurements done with activation foils.

  13. On flattening filter-free portal dosimetry.

    PubMed

    Pardo, Eduardo; Castro Novais, Juan; Molina López, María Yolanda; Ruiz Maqueda, Sheila

    2016-01-01

    Varian introduced (in 2010) the option of removing the flattening filter (FF) in their C-Arm linacs for intensity-modulated treatments. This mode, called flattening filter-free (FFF), offers the advantage of a greater dose rate. Varian's "Portal Dosimetry" is an electronic portal imager device (EPID)-based tool for IMRT verification. This tool lacks the capability of verifying flattening filter-free (FFF) modes due to saturation and lack of an image prediction algorithm. (Note: the latest versions of this software and EPID correct these issues.) The objective of the present study is to research the feasibility of said verifications (with the older versions of the software and EPID). By placing the EPID at a greater distance, the images can be acquired without saturation, yielding a linearity similar to the flattened mode. For the image prediction, a method was optimized based on the clinically used algorithm (analytical anisotropic algorithm (AAA)) over a homogeneous phantom. The depth inside the phantom and its electronic density were tailored. An application was developed to allow the conversion of a dose plane (in DICOM format) to Varian's custom format for Portal Dosimetry. The proposed method was used for the verification of test and clinical fields for the three qualities used in our institution for IMRT: 6X, 6FFF and 10FFF. The method developed yielded a positive verification (more than 95% of the points pass a 2%/2 mm gamma) for both the clinical and test fields. This method was also capable of "predicting" static and wedged fields. A workflow for the verification of FFF fields was developed. This method relies on the clinical algorithm used for dose calculation and is able to verify the FFF modes, as well as being useful for machine quality assurance. The procedure described does not require new hardware. This method could be used as a verification of Varian's Portal Dose Image Prediction. PMID:27455487

  14. Thermoluminescent Dosimetry: A Preliminary Study for microCT Applications

    SciTech Connect

    Montano Garcia, C.; Rodriguez-Villafuerte, M.; Martinez-Davalos, A.; Brandan, M. E.; Ruiz-Trejo, C.

    2006-09-08

    Preliminary measurements for microCT dosimetry are reported in this work, using TLD-100 crystals (1x1x1 mm3) within a solid water phantom specially designed with approximate dimensions of a mouse. A dose dependence as a function of radial distance and position along the axis of the phantom was found. Because of the smaller doses used in this work we can say that it is feasible to perform dosimetry measurements with high accuracy using TLD-100 microcubes.

  15. Hanford Internal Dosimetry Program Manual, PNL-MA-552

    SciTech Connect

    Carbaugh, Eugene H.; Bihl, Donald E.; Maclellan, Jay A.

    2003-10-10

    This manual is a guide to the services provided by the Hanford Internal Dosimetry Program (IDP). It describes the roles of and relationships between the IDP and site contractors, and provides recommendations and guidance for consideration in implementing bioassay monitoring and internal dosimetry elements of radiation protection programs. Guidance includes identifying conditions under which workers should be placed on bioassay programs, types, descritptions, and capabilities of measurements, suggested routine bioassay programs, limitations on services, and practices for recording and reporting results.

  16. EPID dosimetry for pretreatment quality assurance with two commercial systems.

    PubMed

    Bailey, Daniel W; Kumaraswamy, Lalith; Bakhtiari, Mohammad; Malhotra, Harish K; Podgorsak, Matthew B

    2012-01-01

    This study compares the EPID dosimetry algorithms of two commercial systems for pretreatment QA, and analyzes dosimetric measurements made with each system alongside the results obtained with a standard diode array. 126 IMRT fields are examined with both EPID dosimetry systems (EPIDose by Sun Nuclear Corporation, Melbourne FL, and Portal Dosimetry by Varian Medical Systems, Palo Alto CA) and the diode array, MapCHECK (also by Sun Nuclear Corporation). Twenty-six VMAT arcs of varying modulation complexity are examined with the EPIDose and MapCHECK systems. Optimization and commissioning testing of the EPIDose physics model is detailed. Each EPID IMRT QA system is tested for sensitivity to critical TPS beam model errors. Absolute dose gamma evaluation (3%, 3 mm, 10% threshold, global normalization to the maximum measured dose) yields similar results (within 1%-2%) for all three dosimetry modalities, except in the case of off-axis breast tangents. For these off-axis fields, the Portal Dosimetry system does not adequately model EPID response, though a previously-published correction algorithm improves performance. Both MapCHECK and EPIDose are found to yield good results for VMAT QA, though limitations are discussed. Both the Portal Dosimetry and EPIDose algorithms, though distinctly different, yield similar results for the majority of clinical IMRT cases, in close agreement with a standard diode array. Portal dose image prediction may overlook errors in beam modeling beyond the calculation of the actual fluence, while MapCHECK and EPIDose include verification of the dose calculation algorithm, albeit in simplified phantom conditions (and with limited data density in the case of the MapCHECK detector). Unlike the commercial Portal Dosimetry package, the EPIDose algorithm (when sufficiently optimized) allows accurate analysis of EPID response for off-axis, asymmetric fields, and for orthogonal VMAT QA. Other forms of QA are necessary to supplement the limitations of the

  17. [Bone marrow stromal damage mediated by immune response activity].

    PubMed

    Vojinović, J; Kamenov, B; Najman, S; Branković, Lj; Dimitrijević, H

    1994-01-01

    The aim of this work was to estimate influence of activated immune response on hematopoiesis in vitro, using the experimental model of BCG immunized BALB/c mice and in patients with chronic immunoactivation: long-lasting infections, autoimmunity or malignancy. We correlated changes in long term bone marrow cultures (Dexter) and NBT reduction with appearance of anemia in patients and experimental model of immunization by BCG. Increased spontaneous NBT reduction pointed out role of macrophage activation in bone marrow stroma damage. Long-term bone marrow cultures showed reduced number of hematopoietic cells, with predomination of fibroblasts and loss of fat cells. This results correlated with anemia and leucocytosis with stimulated myelopoiesis in peripheral blood. Activation of immune response, or acting of any agent that directly changes extracellular matrix and cellularity of bone marrow, may result in microenviroment bone marrow damage that modify hematopoiesis. PMID:18173180

  18. Effects of low level light irradiation on the migration of mesenchymal stem cells derived from rat bone marrow.

    PubMed

    Li, Wen-Tyng; Chen, Chih-Wei; Huang, Po-Ya

    2013-01-01

    Low level light irradiation (LLLI) was found to exert positive effects on various cells in vitro. The aim of this study was to investigate the effect of LLLI on the migration of rat bone marrow mesenchymal stem cells (rbMSCs). Light irradiation was applied at the energy density of 4 J/cm(2) using red (630 nm) and near infrared (NIR, 850 nm) light emitting diodes (LEDs). Wound healing assay showed both red and NIR light irradiation increased cell mobility. Red and NIR light enhanced transmembrane migration of rbMSCs up to 292.9% and 263.6% accordingly. This agreed with enzymatic activities of MMP-2 and MMP-9 enhanced by irradiation. F-actin accumulation and distribution correlated to increased migration in light-irradiated MSCs. Reactive oxygen species production as well as the expression of pFAK and pNF-кB were elevated after red and NIR LLLI. The study demonstrated that red and NIR LLLI increased rbMSCs migration and identified the phosphorylation of FAK and NF-кB as critical steps for the elevated cell migration upon LLLI. PMID:24110639

  19. Specific issues in small animal dosimetry and irradiator calibration

    PubMed Central

    Yoshizumi, Terry; Brady, Samuel L.; Robbins, Mike E.; Bourland, J. Daniel

    2013-01-01

    Purpose In response to the increased risk of radiological terrorist attack, a network of Centers for Medical Countermeasures against Radiation (CMCR) has been established in the United States, focusing on evaluating animal model responses to uniform, relatively homogenous whole- or partial-body radiation exposures at relatively high dose rates. The success of such studies is dependent not only on robust animal models but on accurate and reproducible dosimetry within and across CMCR. To address this issue, the Education and Training Core of the Duke University School of Medicine CMCR organised a one-day workshop on small animal dosimetry. Topics included accuracy in animal dosimetry accuracy, characteristics and differences of cesium-137 and X-ray irradiators, methods for dose measurement, and design of experimental irradiation geometries for uniform dose distributions. This paper summarises the information presented and discussed. Conclusions Without ensuring accurate and reproducible dosimetry the development and assessment of the efficacy of putative countermeasures will not prove successful. Radiation physics support is needed, but is often the weakest link in the small animal dosimetry chain. We recommend: (i) A user training program for new irradiator users, (ii) subsequent training updates, and (iii) the establishment of a national small animal dosimetry center for all CMCR members. PMID:21961967

  20. Personnel neutron dosimetry using electrochemically etched CR-39 foils

    SciTech Connect

    Hankins, D.E.; Homann, S.; Westermark, J.

    1986-09-17

    A personnel neutron dosimetry system has been developed based on the electrochemical etching of CR-39 plastic at elevated temperatures. The doses obtained using this dosimeter system are more accurate than those obtained using other dosimetry systems, especially when varied neutron spectra are encountered. This Cr-39 dosimetry system does not have the severe energy dependence that exists with albedo neutron dosimeters or the fading and reading problems encountered with NTA film. The dosimetry system employs an electrochemical etch procedure that be used to process large numbers of Cr-39 dosimeters. The etch procedure is suitable for operations where the number of personnel requires that many CR-39 dosimeters be processed. Experience shows that one full-time technician can etch and evaluate 2000 foils per month. The energy response to neutrons is fairly flat from about 80 keV to 3.5 MeV, but drops by about a factor of three in the 13 to 16 MeV range. The sensitivity of the dosimetry system is about 7 tracks/cm/sup 2//mrem, with a background equivalent to about 8 mrem for new CR-39 foils. The limit of sensitivity is approximately 10 mrem. The dosimeter has a significant variation in directional dependence, dropping to about 20% at 90/sup 0/. This dosimeter has been used for personnel neutron dosimetry at the Lawrence Livermore National Laboratory for more tha 18 months. 6 refs., 23 figs., 2 tabs.

  1. Boron dose determination for BNCT using Fricke and EPR dosimetry

    SciTech Connect

    Wielopolski, L.; Ciesielski, B.

    1995-02-01

    In Boron Neutron Capture Therapy (BNCT) the dominant dose delivered to the tumor is due to {alpha} and {sup 7}Li charged particles resulting from a neutron capture by {sup 10}B and is referred to herein as the boron dose. Boron dose is directly attributable to the following two independent factors, one boron concentration and the neutron capture energy dependent cross section of boron, and two the energy spectrum of the neutrons that interact with boron. The neutron energy distribution at a given point is dictated by the incident neutron energy distribution, the depth in tissue, geometrical factors such as beam size and patient`s dimensions. To account for these factors can be accommodated by using Monte Carlo theoretical simulations. However, in conventional experimental BNCT dosimetry, e.g., using TLDs or ionization chambers, it is only possible to estimate the boron dose. To overcome some of the limitations in the conventional dosimetry, modifications in ferrous sulfate dosimetry (Fricke) and Electron Paramagnetic Resonance (EPR) dosimetry in alanine, enable to measure specifically boron dose in a mixed gamma neutron radiation fields. The boron dose, in either of the dosimeters, is obtained as a difference between measurements with boronated and unboronated dosimeters. Since boron participates directly in the measurements, the boron dosimetry reflects the true contribution, integral of the neutron energy spectrum with boron cross section, of the boron dose to the total dose. Both methods are well established and used extensively in dosimetry, they are presented briefly here.

  2. Review of the near-earth space radiation dosimetry

    NASA Astrophysics Data System (ADS)

    Guo, Jianming; Chen, Xiaoqian; Li, Shiyou

    2016-07-01

    The near-earth space radiation environment has a great effect to the spacecraft and maybe do harm to the astronaut's health. Thus, how to measure the radiation has become a serious challenge. In order to provide sufficient protection both for astronauts and for instruments on-board, dose equivalent and linear energy transfer should be measured instead of merely measuring total radiation dose. This paper reviews the methods of radiation measurement and presents a brief introduction of dosimetry instruments. The method can be divided into two different kinds, i.e., positive dosimetry and passive dosimetry. The former usually includes electronic devices which can be used for data storage and can offer simultaneous monitoring on space radiation. The passive dosimetry has a much simple structure, and need extra operation after on-orbit missions for measuring. To get more reliable data of radiation dosimetry, various instruments and methods had been applied in the spacecrafts and the manned spacecrafts in particular. The outlook of the development in the space radiation dosimetry measurement is also presented.

  3. ESR dosimetry for atomic bomb survivors and radiologic technologists

    NASA Astrophysics Data System (ADS)

    Tatsumi-Miyajima, Junko

    1987-06-01

    An individual absorbed dose for atomic bomb (A-bomb) survivors and radiologic technologists has been estimated using a new personal dosimetry. This dosimetry is based on the electron spin resonance (ESR) spectroscopy of the CO 33- radicals, which are produced in their teeth by radiation. Measurements were carried out to study the characteristics of the dosimetry; the ESR signals of the CO 33- radicals were stable and increased linearly with the radiation dose. In the evaluation of the absorbed dose, the ESR signals were considered to be a function of photon energy. The absorbed doses in ten cases of A-bomb victims and eight cases of radiologic technologists were determined. For A-bomb survivors, the adsorbed doses, which were estimated using the ESR dosimetry, were consistent with the ones obtained using the calculations of the tissue dose in air of A-bomb, and also with the ones obtained using the chromosome measurements. For radiologic technologists, the absorbed doses, which were estimated using the ESR dosimetry, agreed with the ones calculated using the information on the occupational history and conditions. The advantages of this method are that the absorbed dose can be directly estimated by measuring the ESR signals obtained from the teeth of persons, who are exposed to radiation. Therefore, the ESR dosimetry is useful to estimate the accidental exposure and the long term cumulative dose.

  4. Bone marrow atrophy induced by murine cytomegalovirus infection.

    PubMed Central

    Gibbons, A E; Price, P; Shellam, G R

    1994-01-01

    Acute, sublethal infection of mice with murine cytomegalovirus (MCMV) resulted in up to 80% decreases in the number of cells recoverable from the bone marrow, and a decrease in peripheral blood leucocyte counts during the first week of infection. Depopulation of the leucopoietic areas of the marrow was evident from examination of histological sections. The severity of bone marrow atrophy in MCMV-infected mice of different strains correlated with previously described genetically determined sensitivity to MCMV disease. Although the phenomenon only occurred when mice were inoculated with infectious virus preparations, fewer than one in 10(5) marrow cells were productively infected, suggesting that atrophy was not due to lytic infection of large numbers of bone marrow cells. Interestingly, increases in serum colony-stimulating activity were observed and these were proportional to the severity of bone marrow atrophy. After MCMV infection, we observed increases in the proportions of cells expressing some B-cell and myeloid cell markers and a decrease in the proportion of cells expressing an erythroid cell marker. There was no change in the frequency of marrow cells expressing mature T-cell markers. The numbers of myeloid lineage-committed progenitor cells (GM-CFU) in the marrow decreased 10- to 20-fold in BALB/c nu/+ mice, while there was a threefold decrease in their numbers in BALB/c nu/nu mice. In addition, increases in serum colony-stimulating activity were greater in BALB/c nu/+ mice than in BALB/c nu/nu mice. Our results suggest that growth factors produced after MCMV infection may accelerate the maturation and migration of cells from the marrow to sites of virus replication and inflammation, thus accounting for the depletion in numbers of marrow cells observed soon after MCMV infection. Images Figure 3 Figure 4 PMID:7959876

  5. Comparative Study of Bone Marrow and Blood B Cells in Infantile and Acquired Agammaglobulinemia

    PubMed Central

    Abdou, Nabih I.; Casella, Salvatore R.; Abdou, Nancy L.; Abrahamsohn, Ises A.

    1973-01-01

    The status of immunoglobulin (Ig) receptors of the bone marrow dependent (B) cells present in either the bone marrow (BM) or peripheral blood (PB) of three patients with infantile agammaglobulinemia (I-AGG), or seven patients with acquired agammaglobulinemia (A-AGG) is compared with those of 12 controls. Quantitative and qualitative changes of the different classes of Ig receptors on B cells were evaluated by their capacity to bind [125I]anti-Ig, to be stained with fluorescinated anti-Ig and their in vitro proliferative capacity upon incubation with the anti-Ig. Patients with I-AGG lacked B cells in both the BM and PB. Whereas BM cells of patients with A-AGG carried receptors similar to control cells, their blood B cells had fewer IgM, IgG, and IgA cells which failed to proliferate in vitro in the presence of the anti-Ig. An anti-IgM of the IgG class was detected in the sera of patients with A-AGG but not in sera of I-AGG. The isolated anti-IgM agglutinated human red cells coated with IgM. The anti-IgM partially blocked the binding of fluorescinated or radiolabeled anti-IgM to IgM peripheral blood lymphocytes of normal controls. The eluted anti-IgM in presence of complement was partially cytotoxic to normal cells. It is concluded that I-AGG-B cell defect is due to failure of B cell development in the bone marrow compartment whereas the peripheral exclusion of IgM cells by an anti-IgM with the subsequent failure of differentiation of both IgG and IgA cells could be an important mechanism in A-AGG-B cell defect. PMID:4580388

  6. Highlights and pitfalls of 20 years of application of computerised glow curve analysis to thermoluminescence research and dosimetry.

    PubMed

    Horowitz, Y S; Moscovitch, M

    2013-01-01

    The technical and dosimetric aspects of computerised glow curve analysis are described in detail including a review of the current 'state-of-the-achieved' in applications to environmental and personal dosimetry, clinical dosimetry, quality control, characterisation of new materials, continuing characterisation of 'old' materials, heavy charged particle dosimetry, mixed field n-gamma dosimetry, X-ray dosimetry and other aspects of thermoluminescence dosimetry. Fearless emphasis is placed on 'pitfalls' as well as successes. PMID:22987121

  7. Exercise Regulation of Marrow Adipose Tissue

    PubMed Central

    Pagnotti, Gabriel M.; Styner, Maya

    2016-01-01

    Despite association with low bone density and skeletal fractures, marrow adipose tissue (MAT) remains poorly understood. The marrow adipocyte originates from the mesenchymal stem cell (MSC) pool that also gives rise to osteoblasts, chondrocytes, and myocytes, among other cell types. To date, the presence of MAT has been attributed to preferential biasing of MSC into the adipocyte rather than osteoblast lineage, thus negatively impacting bone formation. Here, we focus on understanding the physiology of MAT in the setting of exercise, dietary interventions, and pharmacologic agents that alter fat metabolism. The beneficial effect of exercise on musculoskeletal strength is known: exercise induces bone formation, encourages growth of skeletally supportive tissues, inhibits bone resorption, and alters skeletal architecture through direct and indirect effects on a multiplicity of cells involved in skeletal adaptation. MAT is less well studied due to the lack of reproducible quantification techniques. In recent work, osmium-based 3D quantification shows a robust response of MAT to both dietary and exercise intervention in that MAT is elevated in response to high-fat diet and can be suppressed following daily exercise. Exercise-induced bone formation correlates with suppression of MAT, such that exercise effects might be due to either calorie expenditure from this depot or from mechanical biasing of MSC lineage away from fat and toward bone, or a combination thereof. Following treatment with the anti-diabetes drug rosiglitazone – a PPARγ-agonist known to increase MAT and fracture risk – mice demonstrate a fivefold higher femur MAT volume compared to the controls. In addition to preventing MAT accumulation in control mice, exercise intervention significantly lowers MAT accumulation in rosiglitazone-treated mice. Importantly, exercise induction of trabecular bone volume is unhindered by rosiglitazone. Thus, despite rosiglitazone augmentation of MAT, exercise

  8. Exercise Regulation of Marrow Adipose Tissue.

    PubMed

    Pagnotti, Gabriel M; Styner, Maya

    2016-01-01

    Despite association with low bone density and skeletal fractures, marrow adipose tissue (MAT) remains poorly understood. The marrow adipocyte originates from the mesenchymal stem cell (MSC) pool that also gives rise to osteoblasts, chondrocytes, and myocytes, among other cell types. To date, the presence of MAT has been attributed to preferential biasing of MSC into the adipocyte rather than osteoblast lineage, thus negatively impacting bone formation. Here, we focus on understanding the physiology of MAT in the setting of exercise, dietary interventions, and pharmacologic agents that alter fat metabolism. The beneficial effect of exercise on musculoskeletal strength is known: exercise induces bone formation, encourages growth of skeletally supportive tissues, inhibits bone resorption, and alters skeletal architecture through direct and indirect effects on a multiplicity of cells involved in skeletal adaptation. MAT is less well studied due to the lack of reproducible quantification techniques. In recent work, osmium-based 3D quantification shows a robust response of MAT to both dietary and exercise intervention in that MAT is elevated in response to high-fat diet and can be suppressed following daily exercise. Exercise-induced bone formation correlates with suppression of MAT, such that exercise effects might be due to either calorie expenditure from this depot or from mechanical biasing of MSC lineage away from fat and toward bone, or a combination thereof. Following treatment with the anti-diabetes drug rosiglitazone - a PPARγ-agonist known to increase MAT and fracture risk - mice demonstrate a fivefold higher femur MAT volume compared to the controls. In addition to preventing MAT accumulation in control mice, exercise intervention significantly lowers MAT accumulation in rosiglitazone-treated mice. Importantly, exercise induction of trabecular bone volume is unhindered by rosiglitazone. Thus, despite rosiglitazone augmentation of MAT, exercise significantly

  9. Multiparameter Analysis of Human Bone Marrow Stromal Cells Identifies Distinct Immunomodulatory and Differentiation-Competent Subtypes

    PubMed Central

    James, Sally; Fox, James; Afsari, Farinaz; Lee, Jennifer; Clough, Sally; Knight, Charlotte; Ashmore, James; Ashton, Peter; Preham, Olivier; Hoogduijn, Martin; Ponzoni, Raquel De Almeida Rocha; Hancock, Y.; Coles, Mark; Genever, Paul

    2015-01-01

    Summary Bone marrow stromal cells (BMSCs, also called bone-marrow-derived mesenchymal stromal cells) provide hematopoietic support and immunoregulation and contain a stem cell fraction capable of skeletogenic differentiation. We used immortalized human BMSC clonal lines for multi-level analysis of functional markers for BMSC subsets. All clones expressed typical BMSC cell-surface antigens; however, clones with trilineage differentiation capacity exhibited enhanced vascular interaction gene sets, whereas non-differentiating clones were uniquely CD317 positive with significantly enriched immunomodulatory transcriptional networks and high IL-7 production. IL-7 lineage tracing and CD317 immunolocalization confirmed the existence of a rare non-differentiating BMSC subtype, distinct from Cxcl12-DsRed+ perivascular stromal cells in vivo. Colony-forming CD317+ IL-7hi cells, identified at ∼1%–3% frequency in heterogeneous human BMSC fractions, were found to have the same biomolecular profile as non-differentiating BMSC clones using Raman spectroscopy. Distinct functional identities can be assigned to BMSC subpopulations, which are likely to have specific roles in immune control, lymphopoiesis, and bone homeostasis. PMID:26070611

  10. Daily variation in radiosensitivity of circulating blood cells and bone marrow cell density in mice

    SciTech Connect

    Tabatabai, R.N.

    1984-01-01

    Mice on a 12/12 light/dark cycle were bled during a twenty-four hour period each week for eight weeks to establish daily values of circulating blood cells. No significant daily variation was found in total red blood cells, hematocrit, or percentage of reticulocytes. A significant (P < 0.001) daily variation was found in total white blood cells, with the minimum occurring at 8 PM and the maximum occurring during the daylight hours from 8 a.m. to 2 p.m. Mice were then exposed to 0 R, 20 R, 50 R, or 100 R of x-radiation to determine what dose significantly reduces the total white cell count in circulating blood. It was found that 100 R significantly (P < .05) reduces the total white cell count over a four week period post-exposure. To determine if circulating blood cells and bone marrow cells show a diurnal radiosensitivity, mice were exposed to 100 R or 200 R of x-radiation at noon or midnight. Hematocrits, reticulocyte and white blood cell counts, daily white blood cell rhythm, and bone marrow cell density indicate that these mice were more radiosensitive at night.

  11. Registration of 'Red Ruby' Wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Red Ruby’ soft red winter wheat (Triticum aestivum L.) was developed by the Michigan Agricultural Experiment Station and released in 2007 via an exclusive licensing agreement through Michigan State University (MSU) Technologies. Red Ruby was selected from the cross Pioneer ‘2552’/Pioneer ‘2737W’ ma...

  12. [Current problems in pediatric bone marrow transplantation].

    PubMed

    Kato, S

    1993-05-01

    Bone marrow transplantation (BMT) has been increasingly applied to a variety of potentially fatal diseases in childhood. However, trends of indication of BMT are changing because chemotherapy in leukemia and immunosuppressive therapy with/without colony stimulating factor in aplastic anemia are improving. Several progresses have been noted in matched unrelated BMT and peripheral blood stem cell transplantation as well as in sibling BMT or autologous BMT. Many efforts are being made to decrease rejection rate or leukemia relapse and to improve quality of life by new conditioning regimens. Attempts to induce GVL effects or syngeneic GVHD are currently under progress. The quality of life in long term surviving children are generally good and acceptable, although delay in growth, infertility, cataract and obstructive lung disease are seen in a few patients. PMID:8315825

  13. Marrow failure: a window into ribosome biology.

    PubMed

    Ruggero, Davide; Shimamura, Akiko

    2014-10-30

    Diamond-Blackfan anemia, Shwachman-Diamond syndrome, and dyskeratosis congenita are inherited syndromes characterized by marrow failure, congenital anomalies, and cancer predisposition. Genetic and molecular studies have uncovered distinct abnormalities in ribosome biogenesis underlying each of these 3 disorders. How defects in ribosomes, the essential organelles required for protein biosynthesis in all cells, cause tissue-specific abnormalities in human disease remains a question of fundamental scientific and medical importance. Here we review the overlapping and distinct clinical features of these 3 syndromes and discuss current knowledge regarding the ribosomal pathways disrupted in each of these disorders. We also explore the increasing complexity of ribosome biology and how this informs our understanding of developmental biology and human disease. PMID:25237201

  14. Marrow Adipose Tissue: Trimming the Fat.

    PubMed

    Scheller, Erica L; Cawthorn, William P; Burr, Aaron A; Horowitz, Mark C; MacDougald, Ormond A

    2016-06-01

    Marrow adipose tissue (MAT) is a unique fat depot, located in the skeleton, that has the potential to contribute to both local and systemic metabolic processes. In this review we highlight several recent conceptual developments pertaining to the origin and function of MAT adipocytes; consider the relationship of MAT to beige, brown, and white adipose depots; explore MAT expansion and turnover in humans and rodents; and discuss future directions for MAT research in the context of endocrine function and metabolic disease. MAT has the potential to exert both local and systemic effects on metabolic homeostasis, skeletal remodeling, hematopoiesis, and the development of bone metastases. The diversity of these functions highlights the breadth of the potential impact of MAT on health and disease. PMID:27094502

  15. Marrow failure: a window into ribosome biology

    PubMed Central

    Ruggero, Davide

    2014-01-01

    Diamond-Blackfan anemia, Shwachman-Diamond syndrome, and dyskeratosis congenita are inherited syndromes characterized by marrow failure, congenital anomalies, and cancer predisposition. Genetic and molecular studies have uncovered distinct abnormalities in ribosome biogenesis underlying each of these 3 disorders. How defects in ribosomes, the essential organelles required for protein biosynthesis in all cells, cause tissue-specific abnormalities in human disease remains a question of fundamental scientific and medical importance. Here we review the overlapping and distinct clinical features of these 3 syndromes and discuss current knowledge regarding the ribosomal pathways disrupted in each of these disorders. We also explore the increasing complexity of ribosome biology and how this informs our understanding of developmental biology and human disease. PMID:25237201

  16. Lung function after bone marrow grafting

    SciTech Connect

    Depledge, M.H.; Barrett, A.; Powles, R.L.

    1983-02-01

    Results of a prospective lung function study are presented for 48 patients with acute myeloid leukemia (AML) treated with total body irradiation (TBI) and bone marrow transplantation (BMT) at the Royal Marsden Hospital between 1978 and 1980. Patients with active disease or who were in remission following cytoreductive chemotherapy had mildly impaired gas exchange prior to grafting. After TBI and BMT all patients studied developed progressive deterioration of lung function during the first 100 days, although these changes were subclinical. Infection and graft-versus-host disease (GvHD) were associated with further worsening of restrictive ventilatory defects and diffusing capacity (D/sub L/CO). Beyond 100 days, ventilatory ability returned to normal and gas transfer improved, although it failed to reach pre-transplant levels. There was no evidence of progressive pulmonary fibrosis during the first year after grafting.

  17. The Inherited Bone Marrow Failure Syndromes

    PubMed Central

    Chirnomas, S. Deborah; Kupfer, Gary M

    2013-01-01

    In spite of the rarity of inherited bone marrow failure syndromes (IBMFS), they represent diseases for which the molecular pathogenesis may be elucidated. Their study and presentation of the details of their molecular biology and biochemistry is warranted not only for appropriate diagnosis and management of afflicted patients but also because they lend clues to the normal physiology of the normal hematopoiesis and, in many cases, mechanisms of carcinogenesis. Several themes have emerged within each subsection of IBMFS, including the ribosomopathies that entail both ribosome assembly as well as ribosomal RNA processing. The Fanconi anemia (FA) pathway itself has become interdigitated with the familial breast cancer syndromes. The sections that follow present a more detailed analysis of the diseases that account for the majority of IBMFS diagnoses. PMID:24237972

  18. A Method for Generation of Bone Marrow-Derived Macrophages from Cryopreserved Mouse Bone Marrow Cells

    PubMed Central

    Lima, Djalma S.; Zamboni, Dario S.

    2010-01-01

    The broad use of transgenic and gene-targeted mice has established bone marrow-derived macrophages (BMDM) as important mammalian host cells for investigation of the macrophages biology. Over the last decade, extensive research has been done to determine how to freeze and store viable hematopoietic human cells; however, there is no information regarding generation of BMDM from frozen murine bone marrow (BM) cells. Here, we establish a highly efficient protocol to freeze murine BM cells and further generate BMDM. Cryopreserved murine BM cells maintain their potential for BMDM differentiation for more than 6 years. We compared BMDM obtained from fresh and frozen BM cells and found that both are similarly able to trigger the expression of CD80 and CD86 in response to LPS or infection with the intracellular bacteria Legionella pneumophila. Additionally, BMDM obtained from fresh or frozen BM cells equally restrict or support the intracellular multiplication of pathogens such as L. pneumophila and the protozoan parasite Leishmania (L.) amazonensis. Although further investigation are required to support the use of the method for generation of dendritic cells, preliminary experiments indicate that bone marrow-derived dendritic cells can also be generated from cryopreserved BM cells. Overall, the method described and validated herein represents a technical advance as it allows ready and easy generation of BMDM from a stock of frozen BM cells. PMID:21179419

  19. Publication bias in blood and marrow transplantation.

    PubMed

    Saeed, Mahwash; Paulson, Kristjan; Lambert, P; Szwajcer, David; Seftel, Matthew

    2011-06-01

    Only a small proportion of abstracts lead to full publication. Abstracts with "positive" results are more likely to be published than other abstracts, leading to publication bias. To date, this issue has not been examined in the blood and marrow transplantation (BMT) literature. We hypothesized that because BMT centers are often based at academic centers, the proportion of abstracts leading to publication will be high. All abstracts presented at the Canadian Blood and Marrow Transplant Group biannual meetings in 2002, 2004, and 2006 were reviewed and categorized by study type, funding source, single-center or multicenter study, form of presentation, and positive or negative results, using the authors' definitions. To determine publication, each reference was searched on multiple databases (MEDLINE, EMBASE, Web of Science, and CINAHL) by first, second, and final author names. Two authors performed abstract categorization and searching, and disagreements were resolved by consensus. Of the 141 abstracts reviewed, only 43 were published (30.4%). Twenty-one studies were published from 2002 (36.8%), compared with 12 from 2004 (24.0%) and 10 from 2006 (29.4%) (P = .35). Neither positive results nor the number of involved centers were associated with the likelihood of publication. Clinical studies (retrospective or prospective) were more likely to be published than nonclinical studies (P = .014). Funded studies and oral presentations were more likely to be published (P = .009 and .004, respectively). A low rate of publication is seen in the field of BMT. Studies with clinical outcomes, externally funded studies, and studies presented orally were more likely to be published. However, there was no publication bias in favor of studies with positive results. Publication bias should be evaluated further at larger BMT meetings, and efforts should be made to encourage full publication of scientific abstracts. PMID:21130176

  20. The great red flashlight

    NASA Astrophysics Data System (ADS)

    Halbach, Edward A.

    After fifty years of fighting with flashlights which persisted in rolling to the ground, being mislaid, or stashed in a pocket, the author designed a unit which was always on hand and needed no search for the switch. A normally closed switch, internal to the bottom of the flashlight case, is opened by the weight of the unit suspended on a cord about the neck. Lifting the unit with two fingers turns on the red light, while releasing the unit automatically turns it off. A felt covering around the flashlight provides comfort on cold nights. Because this red light would be a welcome tool for other variable star observers, more units were assembled and brought to the AAVSO meeting in Houston for distribution to observers who agreed to give each unit a workout and report on its performance. The author is waiting to hear from these observers.

  1. EDITORIAL: Special issue on radiation dosimetry Special issue on radiation dosimetry

    NASA Astrophysics Data System (ADS)

    Sharpe, Peter

    2009-04-01

    This special issue of Metrologia on radiation dosimetry is the second in a trilogy on the subject of ionizing radiation measurements, a field that is overseen by Sections I, II and III of the CIPM's Consultative Committee for Ionizing Radiation (CCRI). The work of Section II, on radionuclide metrology, was covered in issue 44(4), published in 2007, and that of Section III, on neutron metrology, will be covered in a special issue to be published shortly. This issue covers the work of Section I (x-rays and γ rays, and charged particles). The proposal to publish special issues of Metrologia covering the work of the CCRI Sections was first made in 2003 and refined at the two subsequent meetings of the CCRI in 2005 and 2007. The overall aim is to present the work of the CCRI to a wider metrological audience and to highlight the relevance and importance of the field. The main focus of our special issue on dosimetry metrology is on the 'state of the art' in the various areas covered, with an indication of the current developments taking place and the problems and challenges that remain. Where appropriate, this is set in a brief historical context, although it is not the aim to give a historical review. The need for accurate measurement has been appreciated from the pioneering days of the use of ionizing radiation in the early 20th century, particularly in the fields of diagnostic and therapeutic medicine. Over the years, the range of applications for ionizing radiation has expanded both in scope and in the types and energies of radiation employed. This has led to the need to develop a wide variety of measurement techniques and standards covering fields ranging from the low doses experienced in environmental and protection applications to the extremely high doses used in industrial processing. The different types of radiation employed give rise to the need for dose measurements in radiation beams whose effective penetration through a material such as water ranges from a

  2. Great Red Spot (GRS)

    NASA Astrophysics Data System (ADS)

    Murdin, P.

    2000-11-01

    A huge permanent anticyclone in Jupiter's southern hemisphere, visible as a reddish oval at just over 20 °S. The earliest unequivocal observation was by Heinrich Schwabe in 1831 (the often-quoted sighting by Robert Hooke in 1664 now seems to have been of a similar but different spot). The GRS became a striking feature around 1880, when it developed a deep red coloration. It was also prominent in ...

  3. Red giants seismology

    NASA Astrophysics Data System (ADS)

    Mosser, B.; Samadi, R.; Belkacem, K.

    2013-11-01

    The space-borne missions CoRoT and Kepler are indiscreet. With their asteroseismic programs, they tell us what is hidden deep inside the stars. Waves excited just below the stellar surface travel throughout the stellar interior and unveil many secrets: how old is the star, how big, how massive, how fast (or slow) its core is dancing. This paper intends to paparazze the red giants according to the seismic pictures we have from their interiors.

  4. Patterns of patient specific dosimetry in total body irradiation

    SciTech Connect

    Akino, Yuichi; McMullen, Kevin P.; Das, Indra J.

    2013-04-15

    Purpose: Total body irradiation (TBI) has been used for bone marrow transplant for hematologic and immune deficiency conditions. The goal of TBI is to deliver a homogeneous dose to the entire body, with a generally accepted range of dose uniformity being within {+-}10% of the prescribed dose. The moving table technique for TBI could make dose uniform in whole body by adjusting couch speed. However, it is difficult to accurately estimate the actual dose by calculation and hence in vivo dosimetry (IVD) is routinely performed. Here, the authors present patterns of patient-specific IVD in 161 TBI patients treated at our institution. Methods: Cobalt-60 teletherapy unit (Model C9 Cobalt-60 teletherapy unit, Picker X-ray Corporation) with customized moving bed (SITI Industrial Products, Inc., Fishers, IN) were used for TBI treatment. During treatment, OneDose{sup TM} (Sicel Technology, NC) Metal Oxide-silicon Semiconductor Field Effect Transistor detectors were placed at patient body surface; both entrance and exit side of the beam at patient head, neck, mediastinum, umbilicus, and knee to estimate midplane dose. When large differences (>10%) between the prescribed and measured dose were observed, dose delivery was corrected for subsequent fractions by the adjustment of couch speed and/or bolus placement. Under IRB exempt status, the authors retrospectively analyzed the treatment records of 161 patients who received TBI treatment between 2006 and 2011. Results: Across the entire cohort, the median {+-} SD (range) percent variance between calculated and measured dose for head, neck, mediastinum, umbilicus, and knee was -2.3 {+-} 10.2% (-66.2 to +35.3), 1.1 {+-} 11.5% (-62.2 to +40.3), -1.9 {+-} 9.5% (-66.4 to +46.6), -1.1 {+-} 7.2% (-35.2 to +42.9), and 3.4 {+-} 12.2% (-47.9 to +108.5), respectively. More than half of treatments were within {+-}10% of the prescribed dose for all anatomical regions. For 80% of treatments (10%-90%), dose at the umbilicus was within {+-}10

  5. Usefulness of bone marrow imaging in childhood malignancies

    SciTech Connect

    Oseas, R.S.; Siddiqui, A.R.; Wellman, H.N.; Baehner, R.L.

    1982-08-01

    Two hundred six /sup 99m/Tc sulfur colloid bone marrow scans in 110 pediatrics patients were reviewed. The normal distribution of sulfur colloid in the lower extremities in various age groups was established. There was progressive loss of uptake with increasing age from less than two years to greater than ten years. Tumor replacement was seen as regions of decreased radioactivity, and the extent of the scan defect paralleled the response of the disease to therapy. Both chemotherapy and irradiation resulted in an extension of the /sup 99m/Tc SC to peripheral marrow sites. In irradiated areas, marrow scan defects were demonstrated and generally recovered normal activity by six months after the completion of therapy. Marrow scan abnormalities caused by tumor replacement were present in four patients despite normal bone scans and radiographs. Ultimate confirmation of tumor involvement was by needle aspiration or biopsy. Persistent marrow defects were seen in two patients with neuroblastoma who had remission of their disease: biopsy revealed myelofibrosis. /sup 99m/Tc sulfur colloid bone marrow scanning is a sensitive monitor of altered marrow activity associated with pediatric hematologic or oncologic diseases.

  6. In Vivo Transplantation of Autogenous Marrow-Derived Cells Following Rapid Intraoperative Magnetic Separation Based on Hyaluronan to Augment Bone Regeneration

    PubMed Central

    Joshi, Powrnima; Fleury, Sean; Luangphakdy, Viviane; Shinohara, Kentaro; Pan, Hui; Boehm, Cynthia; Vasanji, Amit; Hefferan, Theresa E.; Walker, Esteban; Yaszemski, Michael; Hascall, Vincent; Zborowski, Maciej

    2013-01-01

    Introduction This project was designed to test the hypothesis that rapid intraoperative processing of bone marrow based on hyaluronan (HA) could be used to improve the outcome of local bone regeneration if the concentration and prevalence of marrow-derived connective tissue progenitors (CTPs) could be increased and nonprogenitors depleted before implantation. Methods HA was used as a marker for positive selection of marrow-derived CTPs using magnetic separation (MS) to obtain a population of HA-positive cells with an increased CTP prevalence. Mineralized cancellous allograft (MCA) was used as an osteoconductive carrier scaffold for loading of HA-positive cells. The canine femoral multidefect model was used and four cylindrical defects measuring 10 mm in diameter and 15 mm in length were grafted with MCA combined with unprocessed marrow or with MS processed marrow that was enriched in HA+ CTPs and depleted in red blood cells and nonprogenitors. Outcome was assessed at 4 weeks using quantitative 3D microcomputed tomography (micro-CT) analysis of bone formation and histomorphological assessment. Results Histomorphological assessment showed a significant increase in new bone formation and in the vascular sinus area in the MS-processed defects. Robust bone formation was found throughout the defect area in both groups (defects grafted with unprocessed marrow or with MS processed marrow.) Percent bone volume in the defects, as assessed by micro-CT, was greater in defects engrafted with MS processed cells, but the difference was not statistically significant. Conclusion Rapid intraoperative MS processing to enrich CTPs based on HA as a surface marker can be used to increase the concentration and prevalence of CTPs. MCA grafts supplemented with heparinized bone marrow or MS processed cells resulted in a robust and advanced stage of bone regeneration at 4 weeks. A greater new bone formation and vascular sinus area was found in defects grafted with MS processed cells

  7. Twenty new ISO standards on dosimetry for radiation processing

    NASA Astrophysics Data System (ADS)

    Farrar, H., IV

    2000-03-01

    Twenty standards on essentially all aspects of dosimetry for radiation processing were published as new ISO standards in December 1998. The standards are based on 20 standard practices and guides developed over the past 14 years by Subcommittee E10.01 of the American Society for Testing and Materials (ASTM). The transformation to ISO standards using the 'fast track' process under ISO Technical Committee 85 (ISO/TC85) commenced in 1995 and resulted in some overlap of technical information between three of the new standards and the existing ISO Standard 11137 Sterilization of health care products — Requirements for validation and routine control — Radiation sterilization. Although the technical information in these four standards was consistent, compromise wording in the scopes of the three new ISO standards to establish precedence for use were adopted. Two of the new ISO standards are specifically for food irradiation applications, but the majority apply to all forms of gamma, X-ray, and electron beam radiation processing, including dosimetry for sterilization of health care products and the radiation processing of fruit, vegetables, meats, spices, processed foods, plastics, inks, medical wastes, and paper. Most of the standards provide exact procedures for using individual dosimetry systems or for characterizing various types of irradiation facilities, but one covers the selection and calibration of dosimetry systems, and another covers the treatment of uncertainties using the new ISO Type A and Type B evaluations. Unfortunately, nine of the 20 standards just adopted by the ISO are not the most recent versions of these standards and are therefore already out of date. To help solve this problem, efforts are being made to develop procedures to coordinate the ASTM and ISO development and revision processes for these and future ASTM-originating dosimetry standards. In the meantime, an additional four dosimetry standards have recently been published by the ASTM but

  8. Improved dosimetry techniques for intravascular brachytherapy

    NASA Astrophysics Data System (ADS)

    Sehgal, Varun

    Coronary artery disease leads to the accumulation of atheromatous plaque leading to coronary stenosis. Coronary intervention techniques such as balloon angioplasty and atherectomy are used to address coronary stenosis and establish a stable lumen thus enhancing blood flow to the myocardium. Restenosis or re-blockage of the arteries is a major limitation of the above mentioned interventional techniques. Neointimal hyperplasia or proliferation of cells in response to the vascular injury as a result of coronary intervention is considered to be one of the major causes of restenosis. Recent studies indicated that irradiation of the coronary lesion site, with radiation doses ranging from 15 to 30 Gy, leads to diminishing neointimal hyperplasia with subsequent reduction in restenosis. The radiation dose is given by catheter-based radiation delivery systems using beta-emitters 90Sr/90Y, 32P and gamma-emitting 192Ir among others. However the dose schema used for dose prescription for these sources are relatively simplistic, and are based on calculations using uniform homogenous water or tissue media and simple cylinder geometry. Stenotic coronary vessels are invariably lined with atheromatous plaque of heterogeneous composition, the radiation dose distribution obtained from such dosimetry data can cause significant variations in the actual dose received by a given patient. Such discrepancies in dose calculation can introduce relatively large uncertainties in the limits of dose window for effective and safe application of intravascular brachytherapy, and consequently in the clinical evaluation of the efficacy of this modality. In this research study we investigated the effect of different geometrical and material heterogeneities, including residual plaque, catheter non-centering, lesion eccentricity and cardiac motion on the radiation dose delivered at the lesion site. Correction factors including dose perturbation factors and dose variation factors have been calculated

  9. Dietary Pseudopurpurin Improves Bone Geometry Architecture and Metabolism in Red-Bone Guishan Goats

    PubMed Central

    Han, TieSuo; Li, Peng; Wang, JianGuo; Liu, GuoWen; Wang, Zhe; Ge, ChangRong; Gao, ShiZheng

    2012-01-01

    Red-colored bones were found initially in some Guishan goats in the 1980s, and they were designated red-boned goats. However, it is not understood what causes the red color in the bone, or whether the red material changes the bone geometry, architecture, and metabolism of red-boned goats. Pseudopurpurin was identified in the red-colored material of the bone in red-boned goats by high-performance liquid chromatography–electrospray ionization–mass spetrometry and nuclear magnetic resonance analysis. Pseudopurpurin is one of the main constituents of Rubia cordifolia L, which is eaten by the goats. The assessment of the mechanical properties and micro-computed tomography showed that the red-boned goats displayed an increase in the trabecular volume fraction, trabecular thickness, and the number of trabeculae in the distal femur. The mean thickness, inner perimeter, outer perimeter, and area of the femoral diaphysis were also increased. In addition, the trabecular separation and structure model index of the distal femur were decreased, but the bone mineral density of the whole femur and the mechanical properties of the femoral diaphysis were enhanced in the red-boned goats. Meanwhile, expression of alkaline phosphatase and osteocalcin mRNA was higher, and the ratio of the receptor activator of the nuclear factor kappa B ligand to osteoprotegerin was markedly lower in the bone marrow of the red-boned goats compared with common goats. To confirm further the effect of pseudopurpurin on bone geometry, architecture, and metabolism, Wistar rats were fed diets to which pseudopurpurin was added for 5 months. Similar changes were observed in the femurs of the treated rats. The above results demonstrate that pseudopurpurin has a close affinity with the mineral salts of bone, and consequently a high level of mineral salts in the bone cause an improvement in bone strength and an enhancement in the structure and metabolic functions of the bone. PMID:22624037

  10. Hanford External Dosimetry Technical Basis Manual PNL-MA-842

    SciTech Connect

    Rathbone, Bruce A.

    2011-04-04

    The Hanford External Dosimetry Technical Basis Manual PNL-MA-842 documents the design and implementation of the external dosimetry system used at the U.S. Department of Energy (DOE) Hanford site. The manual describes the dosimeter design, processing protocols, dose calculation methodology, radiation fields encountered, dosimeter response characteristics, limitations of dosimeter design under field conditions, and makes recommendations for effective use of the dosimeters in the field. The manual describes the technical basis for the dosimetry system in a manner intended to help ensure defensibility of the dose of record at Hanford and to demonstrate compliance with requirements of 10 CFR 835, the DOE Laboratory Accreditation Program, the DOE Richland Operations Office, DOE Office of River Protection, DOE Pacific Northwest Office of Science, and Hanford’s DOE contractors. The dosimetry system is operated by the Pacific Northwest National Laboratory (PNNL) Hanford External Dosimetry Program which provides dosimetry services to PNNL and all Hanford contractors. The primary users of this manual are DOE and DOE contractors at Hanford using the dosimetry services of PNNL. Development and maintenance of this manual is funded directly by DOE and DOE contractors. Its contents have been reviewed and approved by DOE and DOE contractors at Hanford through the Hanford Personnel Dosimetry Advisory Committee which is chartered and chaired by DOE-RL and serves as means of coordinating dosimetry practices across contractors at Hanford. This manual was established in 1996. Since its inception, it has been revised many times and maintained by PNNL as a controlled document with controlled distribution. The first revision to be released through PNNL’s Electronic Records & Information Capture Architecture database was designated Revision 0. Revision numbers that are whole numbers reflect major revisions typically involving significant changes to all chapters in the document. Revision

  11. Hanford External Dosimetry Technical Basis Manual PNL-MA-842

    SciTech Connect

    Rathbone, Bruce A.

    2010-04-01

    The Hanford External Dosimetry Technical Basis Manual PNL-MA-842 documents the design and implementation of the external dosimetry system used at the U.S. Department of Energy (DOE) Hanford site. The manual describes the dosimeter design, processing protocols, dose calculation methodology, radiation fields encountered, dosimeter response characteristics, limitations of dosimeter design under field conditions, and makes recommendations for effective use of the dosimeters in the field. The manual describes the technical basis for the dosimetry system in a manner intended to help ensure defensibility of the dose of record at Hanford and to demonstrate compliance with requirements of 10 CFR 835, the DOE Laboratory Accreditation Program, the DOE Richland Operations Office, DOE Office of River Protection, DOE Pacific Northwest Office of Science, and Hanford’s DOE contractors. The dosimetry system is operated by the Pacific Northwest National Laboratory (PNNL) Hanford External Dosimetry Program which provides dosimetry services to PNNL and all Hanford contractors. The primary users of this manual are DOE and DOE contractors at Hanford using the dosimetry services of PNNL. Development and maintenance of this manual is funded directly by DOE and DOE contractors. Its contents have been reviewed and approved by DOE and DOE contractors at Hanford through the Hanford Personnel Dosimetry Advisory Committee which is chartered and chaired by DOE-RL and serves as means of coordinating dosimetry practices across contractors at Hanford. This manual was established in 1996. Since its inception, it has been revised many times and maintained by PNNL as a controlled document with controlled distribution. The first revision to be released through PNNL’s Electronic Records & Information Capture Architecture database was designated Revision 0. Revision numbers that are whole numbers reflect major revisions typically involving significant changes to all chapters in the document. Revision

  12. Hanford External Dosimetry Technical Basis Manual PNL-MA-842

    SciTech Connect

    Rathbone, Bruce A.

    2007-03-12

    The Hanford External Dosimetry Technical Basis Manual PNL-MA-842 documents the design and implementation of the external dosimetry system used at Hanford. The manual describes the dosimeter design, processing protocols, dose calculation methodology, radiation fields encountered, dosimeter response characteristics, limitations of dosimeter design under field conditions, and makes recommendations for effective use of the dosimeters in the field. The manual describes the technical basis for the dosimetry system in a manner intended to help ensure defensibility of the dose of record at Hanford and to demonstrate compliance with 10 CFR 835, DOELAP, DOE-RL, ORP, PNSO, and Hanford contractor requirements. The dosimetry system is operated by PNNL’s Hanford External Dosimetry Program (HEDP) which provides dosimetry services to all Hanford contractors. The primary users of this manual are DOE and DOE contractors at Hanford using the dosimetry services of PNNL. Development and maintenance of this manual is funded directly by DOE and DOE contractors. Its contents have been reviewed and approved by DOE and DOE contractors at Hanford through the Hanford Personnel Dosimetry Advisory Committee (HPDAC) which is chartered and chaired by DOE-RL and serves as means of coordinating dosimetry practices across contractors at Hanford. This manual was established in 1996. Since inception, it has been revised many times and maintained by PNNL as a controlled document with controlled distribution. Rev. 0 marks the first revision to be released through PNNL’s Electronic Records & Information Capture Architecture (ERICA) database. Revision numbers that are whole numbers reflect major revisions typically involving changes to all chapters in the document. Revision numbers that include a decimal fraction reflect minor revisions, usually restricted to selected chapters or selected pages in the document. Revision Log: Rev. 0 (2/25/2005) Major revision and expansion. Rev. 0.1 (3/12/2007) Minor

  13. Biological dosimetry by interphase chromosome painting

    NASA Technical Reports Server (NTRS)

    Durante, M.; George, K.; Yang, T. C.

    1996-01-01

    Both fluorescence in situ hybridization of metaphase spreads with whole-chromosome probes and premature chromosome condensation in interphase nuclei have been used in the past to estimate the radiation dose to lymphocytes. We combined these techniques to evaluate the feasibility of using painted interphase chromosomes for biodosimetry. Human peripheral lymphocytes were exposed to gamma rays and fused to mitotic Chinese hamster cells either immediately after irradiation or after 8 h incubation at 37 degrees C. Interphase or metaphase human chromosomes were hybridized with a composite probe specific for human chromosomes 3 and 4. The dose-response curve for fragment induction immediately after irradiation was linear; these results reflected breakage frequency in the total genome in terms of DNA content per chromosome. At 8 h after irradiation, the dose-response curve for chromosome interchanges, the prevalent aberration in interphase chromosomes, was linear-quadratic and similar to that observed for metaphase chromosomes. These results suggest that painting prematurely condensed chromosomes can be useful for biological dosimetry when blood samples are available shortly after the exposure, or when interphase cells are to be scored instead of mitotic cells.

  14. Optical dosimetry for interstitial photodynamic therapy

    SciTech Connect

    Arnfield, M.R.; Tulip, J.; Chetner, M.; McPhee, M.S. )

    1989-07-01

    An approach to photodynamic treatment of tumors is the interstitial implantation of fiber optic light sources. Dosimetry is critical in identifying regions of low light intensity in the tumor which may prevent tumor cure. We describe a numerical technique for calculating light distributions within tumors, from multiple fiber optic sources. The method was tested using four translucent plastic needles, which were placed in a 0.94 X 0.94 cm grid pattern within excised Dunning R3327-AT rat prostate tumors. A cylindrical diffusing fiber tip, illuminated by 630 nm dye laser light was placed within one needle and a miniature light detector was placed within another. The average penetration depth in the tumor region between the two needles was calculated from the optical power measured by the detector, using a modified diffusion theory. Repeating the procedure for each pair of needles revealed significant variations in penetration depth within individual tumors. Average values of penetration depth, absorption coefficient, scattering coefficient, and mean scattering cosine were 0.282 cm, 0.469 cm-1, 250 cm-1 and 0.964, respectively. Calculated light distributions from four cylindrical sources in tumors gave reasonable agreement with direct light measurements using fiber optic probes.

  15. Calibration facility for environment dosimetry instruments

    SciTech Connect

    Bercea, Sorin; Celarel, Aurelia; Cenusa, Constantin

    2013-12-16

    In the last ten years, the nuclear activities, as well as the major nuclear events (see Fukushima accident) had an increasing impact on the environment, merely by contamination with radioactive materials. The most conferment way to quickly identify the presence of some radioactive elements in the environment, is to measure the dose-equivalent rate H. In this situation, information concerning the values of H due only to the natural radiation background must exist. Usually, the values of H due to the natural radiation background, are very low (∼10{sup −9} - 10{sup −8} Sv/h). A correct measurement of H in this range involve a performing calibration of the measuring instruments in the measuring range corresponding to the natural radiation background lead to important problems due to the presence of the natural background itself the best way to overlap this difficulty is to set up the calibration stand in an area with very low natural radiation background. In Romania, we identified an area with such special conditions at 200 m dept, in a salt mine. This paper deals with the necessary requirements for such a calibration facility, as well as with the calibration stand itself. The paper includes also, a description of the calibration stand (and images) as well as the radiological and metrological parameters. This calibration facilities for environment dosimetry is one of the few laboratories in this field in Europe.

  16. Film Dosimetry for Intensity Modulated Radiation Therapy

    NASA Astrophysics Data System (ADS)

    Benites-Rengifo, J.; Martínez-Dávalos, A.; Celis, M.; Lárraga, J.

    2004-09-01

    Intensity Modulated Radiation Therapy (IMRT) is an oncology treatment technique that employs non-uniform beam intensities to deliver highly conformal radiation to the targets while minimizing doses to normal tissues and critical organs. A key element for a successful clinical implementation of IMRT is establishing a dosimetric verification process that can ensure that delivered doses are consistent with calculated ones for each patient. To this end we are developing a fast quality control procedure, based on film dosimetry techniques, to be applied to the 6 MV Novalis linear accelerator for IMRT of the Instituto Nacional de Neurología y Neurocirugía (INNN) in Mexico City. The procedure includes measurements of individual fluence maps for a limited number of fields and dose distributions in 3D using extended dose-range radiographic film. However, the film response to radiation might depend on depth, energy and field size, and therefore compromise the accuracy of measurements. In this work we present a study of the dependence of Kodak EDR2 film's response on the depth, field size and energy, compared with those of Kodak XV2 film. The first aim is to devise a fast and accurate method to determine the calibration curve of film (optical density vs. doses) commonly called a sensitometric curve. This was accomplished by using three types of irradiation techniques: Step-and-shoot, dynamic and static fields.

  17. Calibration facility for environment dosimetry instruments

    NASA Astrophysics Data System (ADS)

    Bercea, Sorin; Celarel, Aurelia; Cenusa, Constantin

    2013-12-01

    In the last ten years, the nuclear activities, as well as the major nuclear events (see Fukushima accident) had an increasing impact on the environment, merely by contamination with radioactive materials. The most conferment way to quickly identify the presence of some radioactive elements in the environment, is to measure the dose-equivalent rate H. In this situation, information concerning the values of H due only to the natural radiation background must exist. Usually, the values of H due to the natural radiation background, are very low (˜10-9 - 10-8 Sv/h). A correct measurement of H in this range involve a performing calibration of the measuring instruments in the measuring range corresponding to the natural radiation background lead to important problems due to the presence of the natural background itself the best way to overlap this difficulty is to set up the calibration stand in an area with very low natural radiation background. In Romania, we identified an area with such special conditions at 200 m dept, in a salt mine. This paper deals with the necessary requirements for such a calibration facility, as well as with the calibration stand itself. The paper includes also, a description of the calibration stand (and images) as well as the radiological and metrological parameters. This calibration facilities for environment dosimetry is one of the few laboratories in this field in Europe.

  18. Current personnel dosimetry practices at DOE facilities

    SciTech Connect

    Fix, J.J.

    1981-05-01

    Only three parameters were included in the personnel occupational exposure records by all facilities. These are employee name, social security number, and whole body dose. Approximate percentages of some other parameters included in the record systems are sex (50%), birthdate (90%), occupation (26%), previous employer radiation exposure (74%), etc. Statistical analysis of the data for such parameters as sex versus dose distribution, age versus dose distribution, cumulative lifetime dose, etc. was apparently seldom done. Less than 50% of the facilities reported having formal documentation for either the dosimeter, records system, or reader. Slightly greater than 50% of facilities reported having routine procedures in place. These are considered maximum percentages because some respondents considered computer codes as formal documentation. The repository receives data from DOE facilities regarding the (a) distribution of annual whole body doses, (b) significant internal depositions, and (c) individual doses upon termination. It is expected that numerous differences exist in the dose data submitted by the different facilities. Areas of significant differences would likely include the determination of non-measurable doses, the methods used to determine previous employer radiation dose, the methods of determining cumulative radiation dose, and assessment of internal doses. Undoubtedly, the accuracy of the different dosimetry systems, especially at low doses, is very important to the credibility of data summaries (e.g., man-rem) provided by the repository.

  19. Reactor dosimetry and RPV life management

    SciTech Connect

    Belousov, S.; Ilieva, K.; Mitev, M.

    2011-07-01

    Reactor dosimetry (RD) is a tool that provides data for neutron fluence accumulated over the reactor pressure vessel (RPV) during the reactor operation. This information, however, is not sufficient for RPV lifetime assessment. The life management of RPV is a multidisciplinary task. To assess whether the RPV steel properties at the current stage (for actual accumulated neutron fluence) of reactor operation are still 'safe enough,' the dependence of material properties on the fluence must be known; this is a task for material science (MS). Moreover, the mechanical loading over the RPV during normal operation and accidence have to be known, as well, for evaluation, if the RPV material integrity in this loading condition and existing cracks is provided. The crack loading path in terms of stress intensity factor is carried out by structural analyses (SA). Pressure and temperature distribution over RPV used in these analyses are obtained from a thermal hydraulic (TH) calculation. The conjunction of RD and other disciplines in RPV integrity assessment is analyzed in accordance with the FFP (fitness for purpose) approach. It could help to improve the efficiency in multi-disciplinary tasks solutions. (authors)

  20. Laser microbeam CT scanning of dosimetry gels

    NASA Astrophysics Data System (ADS)

    Maryanski, Marek J.; Ranade, Manisha K.

    2001-06-01

    A novel design of an optical tomographic scanner is described that can be used for 3D mapping of optical attenuation coefficient within translucent cylindrical objects with spatial resolution on the order of 100 microns. Our scanner design utilizes the cylindrical geometry of the imaged object to obtain the desired paths of the scanning light rays. A rotating mirror and a photodetector are placed at two opposite foci of the translucent cylinder that acts as a cylindrical lens. A He-Ne laser beam passes first through a focusing lens and then is reflected by the rotating mirror, so as to scan the interior of the cylinder with focused and parallel paraxial rays that are subsequently collected by the photodetector to produce the projection data, as the cylinder rotates in small angle increments between projections. Filtered backprojection is then used to reconstruct planar distributions of optical attenuation coefficient in the cylinder. Multiplanar scans are used to obtain a complete 3D tomographic reconstruction. Among other applications, the scanner can be used in radiation therapy dosimetry and quality assurance for mapping 3D radiation dose distributions in various types of tissue-equivalent gel phantoms that change their optical attenuation coefficients in proportion to the absorbed radiation dose.

  1. Retrospective Reactor Dosimetry with Zirconium Alloy Samples

    SciTech Connect

    Greenwood, Lawrence R.; Foster, John P.

    2009-11-01

    Retrospective measurements are routinely performed with stainless steel samples. Recent experiments have been successfully conducted using zirconium alloy samples, involving somewhat different neuron activation reactions than are normally encountered with stainless steel samples. The alloy composition consisted of nominally 1% (by weight) niobium, 1% tin, and 0.1% iron, with the balance zirconium. The activation products observed in the samples by gamma spectroscopy included Zr-95, Nb-95, Sn-113, Sb-125, Mn-54, Co-60, Nb-94, and Ta-182. The niobium was then chemically separated following ASTM procedure E1297 and the Nb-93m activities were measured by x-ray spectroscopy. The thermal neutron fluences, as determined independently by the neutron capture gamma reactions to Zr-95, Sn-113, Nb-94, and Sn/Sb-125, were in excellent agreement. The fast neutron fluences, as determined separately by the Fe-54(n,p)Mn-54 and Nb-93(n,n’)Nb-93m reactions, were also in good agreement, thus demonstrating the versatility of the retrospective dosimetry technique.

  2. Biological dosimetry in Russian and Italian astronauts

    NASA Astrophysics Data System (ADS)

    Greco, O.; Durante, M.; Gialanella, G.; Grossi, G.; Pugliese, M.; Scampoli, P.; Snigiryova, G.; Obe, G.

    Large uncertainties are associated with estimates of equivalent dose and cancer risk for crews of longterm space missions. Biological dosimetry in astronauts is emerging as a useful technique to compare predictions based on quality factors and risk coefficients with actual measurements of biological damage in-flight. In the present study, chromosomal aberrations were analyzed in one Italian and eight Russian cosmonauts following missions of different duration on the MIR and the international space station (ISS). We used the technique of fluorescence in situ hybridization (FISH) to visualize translocations in chromosomes 1 and 2. In some cases, an increase in chromosome damage was observed after flight, but no correlation could be found between chromosome damage and flight history, in terms of number of flights at the time of sampling, duration in space and extra-vehicular activity. Blood samples from one of the cosmonauts were exposed in vitro to 6 MeV X-rays both before and after the flight. An enhancement in radiosensitivity induced by the spaceflight was observed.

  3. Effects of the extract of Ginkgo biloba on the differentiation of bone marrow mesenchymal stem cells in vitro

    PubMed Central

    Wu, Zhe; Zhang, Jiadi; Gu, Xu; Zhang, Xiaoxiao; Shi, Shuman; Liu, Chang

    2016-01-01

    The balance of osteogenesis and adipogenesis in bone marrow mesenchymal stem cells (BMSCs) is disrupted in osteoporosis. This study was designed to investigate the effects of extract of Ginkgo biloba (EGB) on proliferation, osteogenic and adipogenic differentiation of bone marrow mesenchymal stem cells in vitro. The effect of EGB on proliferation was evaluated by CCK-8 assay and flow cytometry. Osteogenic differentiation was evaluated by Alizarin Red S staining and Alkaline phosphatase assay. Adipogenic differentiation was evaluated by Oil Red O staining. Quantitative real-time polymerase chain reaction (Real-time PCR) was used to detect the expression of osteogenic specific genes (BMP-2, Runx2 and Colla1) and adipogenic specific genes (ap2, PPARγ). EGB did not significantly affect proliferation of BMSCs. However, it increased the calcium accumulation and significantly promoted the activity of alkaline phosphatase, especially when the concentration of EGB reached 150 µg/mL. EGB dose-dependently inhibited the adipogenic ability of BMSCs. The osteogenic-related genes (BMP-2, Runx2, Colla1) were overexpressed while the expression of genes involved in adipogenesis, such as PPAR-γ and ap2, was decreasing with the increase of EGB concentration. Our data proves that EGB inhibited adipocyte differentiation and enhanced osteogenic differentiation in BMSCs, but had no effect on the proliferation of BMSCs. PMID:27508023

  4. Effects of the extract of Ginkgo biloba on the differentiation of bone marrow mesenchymal stem cells in vitro.

    PubMed

    Wu, Zhe; Zhang, Jiadi; Gu, Xu; Zhang, Xiaoxiao; Shi, Shuman; Liu, Chang

    2016-01-01

    The balance of osteogenesis and adipogenesis in bone marrow mesenchymal stem cells (BMSCs) is disrupted in osteoporosis. This study was designed to investigate the effects of extract of Ginkgo biloba (EGB) on proliferation, osteogenic and adipogenic differentiation of bone marrow mesenchymal stem cells in vitro. The effect of EGB on proliferation was evaluated by CCK-8 assay and flow cytometry. Osteogenic differentiation was evaluated by Alizarin Red S staining and Alkaline phosphatase assay. Adipogenic differentiation was evaluated by Oil Red O staining. Quantitative real-time polymerase chain reaction (Real-time PCR) was used to detect the expression of osteogenic specific genes (BMP-2, Runx2 and Colla1) and adipogenic specific genes (ap2, PPARγ). EGB did not significantly affect proliferation of BMSCs. However, it increased the calcium accumulation and significantly promoted the activity of alkaline phosphatase, especially when the concentration of EGB reached 150 µg/mL. EGB dose-dependently inhibited the adipogenic ability of BMSCs. The osteogenic-related genes (BMP-2, Runx2, Colla1) were overexpressed while the expression of genes involved in adipogenesis, such as PPAR-γ and ap2, was decreasing with the increase of EGB concentration. Our data proves that EGB inhibited adipocyte differentiation and enhanced osteogenic differentiation in BMSCs, but had no effect on the proliferation of BMSCs. PMID:27508023

  5. Isolation, Characterization and Growth Kinetic Comparison of Bone Marrow and Adipose Tissue Mesenchymal Stem Cells of Guinea Pig

    PubMed Central

    Aliborzi, Ghaem; Vahdati, Akbar; Mehrabani, Davood; Hosseini, Seyed Ebrahim; Tamadon, Amin

    2016-01-01

    Background Mesenchymal stem cells (MSCs) from different sources have different characteristics. Moreover, MSCs are not isolated and characterized in Guinea pig for animal model of cell therapy. Aim of the Work was the isolating of bone marrow MSCs (BM-MSCs) and adipose tissue MSCs (AT-MSCs) from Guinea pig and assessing their characteristics. Material and Methods In this study, bone marrow and adipose tissue were collected from three Guinea pigs and cultured and expanded through eight passages. BM-MSCs and AT-MSCs at passages 2, 5 and 8 were seeded in 24-well plates in triplicate. Cells were counted from each well 1~7 days after seeding to determine population doubling time (PDT) and cell growth curves. Cells of passage 3 were cultured in osteogenic and adipogenic differentiation media. Results: BM-MSCs and AT-MSCs attached to the culture flask and displayed spindle-shaped morphology. Proliferation rate of AT-MSCs in the analyzed passages was more than BM-MSCs. The increase in the PDT of MSCs occurs with the increase in the number of passages. Moreover, after culture of BM-MSCs and AT-MSCs in differentiation media, the cells differentiated toward osteoblasts and adipocytes as verified by Alizarin Red staining and Oil Red O staining, respectively. Conclusion BM-MSCs and AT-MSCs of Guinea pig could be valuable source of multipotent stem cells for use in experimental and preclinical studies in animal models. PMID:27426093

  6. Inhibition of adipogenic differentiation of bone marrow mesenchymal stem cells by erythropoietin via activating ERK and P38 MAPK.

    PubMed

    Liu, G X; Zhu, J C; Chen, X Y; Zhu, A Z; Liu, C C; Lai, Q; Chen, S T

    2015-01-01

    We examined whether erythropoietin (EPO) can inhibit adipogenic differentiation of mesenchymal stem cells (MSCs) in the mouse bone marrow and its underlying mechanism. We separated and extracted mouse bone marrow MSCs and induced adipogenic differen-tiation using 3-isobutyl-1-methylxanthine, insulin, and dexamethasone. Different concentrations of EPO were added to the cells and observed by Oil Red O staining on the 20th day to quantitatively analyze the degree of cell differentiation. mRNA expression levels of peroxysome proliferator-activated receptor γ (PPARγ), CCAAT enhancer binding protein α, and adiponectin were analyzed by real-time quantitative polymerase chain reaction, and the activity of PPARγ, extracellular sig-nal-regulated kinase (ERK), and p38 mitogen-activated protein kinase (p38 MAPK) were determined by western blotting. EPO significantly inhibited adipogenic differentiation of MSCs after 20 days and reduced absorbance values by Oil Red O staining without affecting proliferation activity. EPO downregulated the mRNA expression of PPARγ, CCAAT enhancer binding protein α, fatty acid binding protein 4, and adiponec-tin during adipogenesis and increased protein phosphorylation of ERK, p38 MAPK, and PPARγ during differentiation. EPO downregulated the mRNA expression of PPARγ, CCAAT enhancer binding protein α, fatty acid binding protein 4, and adiponectin by increasing protein phosphor-ylation of ERK, p38 MAPK, and PPARγ during differentiation, which inhibited adipogenic differentiation of MSCs. PMID:26125905

  7. 3D dosimetry by optical-CT scanning

    PubMed Central

    Oldham, Mark

    2007-01-01

    The need for an accurate, practical, low-cost 3D dosimetry system is becoming ever more critical as modern dose delivery techniques increase in complexity and sophistication. A recent report from the Radiological Physics Center (RPC) (1), revealed that 38% of institutions failed the head-and-neck IMRT phantom credentialing test at the first attempt. This was despite generous passing criteria (within 7% dose-difference or 4mm distance-to-agreement) evaluated at a half-dozen points and a single axial plane. The question that arises from this disturbing finding is – what percentage of institutions would have failed if a comprehensive 3D measurement had been feasible, rather than measurements restricted to the central film-plane and TLD points? This question can only be adequately answered by a comprehensive 3D-dosimetry system, which presents a compelling argument for its development as a clinically viable low cost dosimetry solution. Optical-CT dosimetry is perhaps the closest system to providing such a comprehensive solution. In this article, we review the origins and recent developments of optical-CT dosimetry systems. The principle focus is on first generation systems known to have highest accuracy but longer scan times. PMID:17460781

  8. Student Perceptions of an Online Medical Dosimetry Program

    SciTech Connect

    Lenards, Nishele

    2011-07-01

    The University of Wisconsin-La Crosse offers the first online medical dosimetry program in the nation. There is no data to research a program of this type. This research consisted of the evaluation of other distance education programs including health profession programs in addition to face-to-face medical dosimetry programs. There was a need to collect and analyze student perceptions of online learning in medical dosimetry. This research provided a guide for future implementation by other programs as well as validated the University of Wisconsin-La Crosse program. Methodology used consisted of an electronic survey sent to all previous and currently enrolled students in the University of Wisconsin-La Crosse medical dosimetry program. The survey was both quantitative and qualitative in demonstrating attitudinal perceptions of students in the program. Quantitative data was collected and analyzed using a 5-point Likert scale. Qualitative data was gathered based on the open-ended responses and the identifying themes from the responses. The results demonstrated an overall satisfaction with this program, the instructor, and the online courses. Students felt a sense of belonging to the courses and the program. Considering that a majority of the students had never taken an online course previously, the students felt there were no technology issues. Future research should include an evaluation of board exam statistics for students enrolled in the online and face-to-face medical dosimetry programs.

  9. SU-E-QI-15: Single Point Dosimetry by Means of Cerenkov Radiation Energy Transfer (CRET)

    SciTech Connect

    Volotskova, O; Jenkins, C; Xing, L

    2014-06-15

    Purpose: Cerenkov light is generated when a charged particles with energy greater then 250 keV, moves faster than the speed of light in a given medium. Both x-ray photons and electrons produce optical Cerenkov photons during the static megavoltage linear accelerator (LINAC) operational mode. Recently, Cerenkov radiation gained considerable interest as possible candidate as a new imaging modality. Optical signals generated by Cerenkov radiation may act as a surrogate for the absorbed superficial radiation dose. We demonstrated a novel single point dosimetry method for megavoltage photon and electron therapy utilizing down conversion of Cerenkov photons. Methods: The custom build signal characterization system was used: a sample holder (probe) with adjacent light tight compartments was connected via fiber-optic cables to a photon counting photomultiplier tube (PMT). One compartment contains a medium only while the other contains medium and red-shifting nano-particles (Q-dots, nanoclusters). By taking the difference between the two signals (Cerenkov photons and CRET photons) we obtain a measure of the down-converted light, which we expect to be proportional to dose as measured with an adjacent ion chamber. Experimental results are compared to Monte Carlo simulations performed using the GEANT4 code. Results: The signal correlation between CR signal, CRET readings and dose produced by LINAC at a single point were investigated. The experimental results were compared with simulations. The dose linearity, signal to noise ratio and dose rate dependence were tested with custom build CRET based probe. Conclusion: Performance characteristics of the proposed single point CRET based probe were evaluated. The direct use of the induced Cerenkov emission and CRET in an irradiated single point volume as an indirect surrogate for the imparted dose was investigated. We conclude that CRET is a promising optical based dosimetry method that offers advantages over those already proposed.

  10. Implementation of IMRT and VMAT using Delta4 phantom and portal dosimetry as dosimetry verification tools

    NASA Astrophysics Data System (ADS)

    Daci, Lulzime; Malkaj, Partizan

    2016-03-01

    In this study we analyzed and compared the dose distribution of different IMRT and VMAT plans with the intent to provide pre-treatment quality assurance using two different tools. Materials/Methods: We have used the electronic portal imaging device EPID after calibration to dose and correction for the background offset signal and also the Delta4 phantom after en evaluation of angular sensitivity. The Delta4 phantom has a two-dimensional array with ionization chambers. We analyzed three plans for each anatomical site calculated by Eclipse treatment planning system. The measurements were analyzed using γ-evaluation method with passing criteria 3% absolute dose and 3 mm distance to agreement (DTA). For all the plans the range of score has been from 97% to 99% for gantry fixed at 0° while for rotational planes there was a slightly decreased pass rates and above 95%. Point measurement with a ionization chamber were done in additional to see the accuracy of portal dosimetry and to evaluate the Delta4 device to various dose rates. Conclusions: Both Delt4 and Portal dosimetry shows good results between the measured and calculated doses. While Delta4 is more accurate in measurements EPID is more time efficient. We have decided to use both methods in the first steps of IMRT and VMAT implementation and later on to decide which of the tools to use depending on the complexity of plans, how much accurate we want to be and the time we have on the machine.

  11. Macroscopic to Microscopic Scales of Particulate Dosimetry: From Source to Fate in the Body

    EPA Science Inventory

    Additional perspective with regards to particle dosimetry is achieved by exploring dosimetry across a range of scales from macroscopic to microscopic in scope. Typically, one thinks of dosimetry as what happens when a particle is inhaled, where it is deposited, and how it is clea...

  12. NIH Blood and Marrow Transplant Late Effects Consensus Conference

    Cancer.gov

    This day and a half symposium will bring together experts in blood and marrow transplantation, late effects, and health care delivery to discuss current evidence and knowledge gaps, develop consensus guidelines, and inform future research in the BMT survivor population.

  13. Who Needs a Blood and Marrow Stem Cell Transplant?

    MedlinePlus

    ... to find out whether you have any medical problems that could cause complications after the transplant. (See "What To Expect Before a Blood and Marrow Stem Cell Transplant" for more information.) Rate This Content: NEXT >> ...

  14. Technetium-99m antimony colloid for bone-marrow imaging

    SciTech Connect

    Martindale, A.A.; Papadimitriou, J.M.; Turner, J.H.

    1980-11-01

    Technetium-99m antimony colloid was prepared in our laboratory for bone-marrow imaging. Optimal production of colloid particles of size range 1 to 13 nm was achieved by the use of polyvinylpyrrolidone of mol. wt. 44,000. Electron microscopy was used to size the particles. Studies in rabbits showed exclusive concentration in the subendothelial dendritic phagocytes of the bone marrow. Pseudopods from these cells were found to traverse interendothelial junctions and concentrate colloid from the sinusoids. Imaging studies of bone marrow in rabbits showed the superiority of the Tc-99m antimony colloid over the much larger colloidal particle of Tc-99m sulfur colloid. Tissue distribution studies in the rat confirmed that bone-marrow uptake of Tc-99m antimony colloid was greater than that of Tc-99m sulfur colloid, although blood clearance was much slower.

  15. Bone scan appearances following biopsy of bone and bone marrow

    SciTech Connect

    McKillop, J.H.; Maharaj, D.; Boyce, B.F.; Fogelman, I.

    1984-10-01

    The influence of sternal marrow aspiration, iliac crest marrow aspiration, and iliac crest bone biopsy on bone scan appearances was examined. Eighteen patients were scanned a mean of 9.9 days after sternal marrow aspiration with a Salah needle. Bone scans obtained in 9 patients a mean of 10 days aftr iliac crest trephine marrow biopsy with a Jamshidi needle showed no abnormality at the biopsy site. In 18 patients with metabolic bone disease who had undergone iliac crest bone biopsy with an 8 mm needle, a scan abnormality due to the biopsy was usually present when the interval between the biopsy and the scan was 5 days to 2 months. Patients who were scanned within 3 days of iliac crest bone biopsy or more than 2 months after biopsy had normal scan appearance at the biopsy site.

  16. [Bone marrow involvement in ovarian cancer determined by immunohistochemical methods].

    PubMed

    Gabriel, M; Obrebowska, A; Spaczyński, M

    2000-01-01

    Atypical epithelial cells in the bone marrow of patients with ovarian cancer were evaluated using immunohistochemical techniques. We investigated cytospin preparations of bone marrow taken from 9 women with benign ovarian tumors and 59 women with malignant ovarian tumors. Two monoclonal antibodies (NCL-C11 and NCL-CA 125) were used. With both antibodies we were able to detect keratin and CA 125 antigen expression in the bone marrow of 9 (18.4%) of the patients with ovarian cancer. With regard to the wide histological differentiation of ovarian carcinomas, the presence of atypical epithelial cells in the bone marrow was required as a prognostic factor for survival and relapses. This should be investigated in a larger study group. PMID:11326158

  17. Understanding Bone Marrow Transplantation as a Treatment Option

    MedlinePlus

    ... you have had, and your overall health. Transplant Process A bone marrow or cord blood transplant is ... The Transplant Process . For more about the search process, HLA matching, and steps of a transplant, such ...

  18. Bone Marrow Diseases - Multiple Languages: MedlinePlus

    MedlinePlus

    ... Supplements Videos & Tools You Are Here: Home → Multiple Languages → All Health Topics → Bone Marrow Diseases URL of this page: https://medlineplus.gov/languages/bonemarrowdiseases.html Other topics A-Z A B ...

  19. Distinct bone marrow blood vessels differentially regulate haematopoiesis.

    PubMed

    Itkin, Tomer; Gur-Cohen, Shiri; Spencer, Joel A; Schajnovitz, Amir; Ramasamy, Saravana K; Kusumbe, Anjali P; Ledergor, Guy; Jung, Yookyung; Milo, Idan; Poulos, Michael G; Kalinkovich, Alexander; Ludin, Aya; Kollet, Orit; Shakhar, Guy; Butler, Jason M; Rafii, Shahin; Adams, Ralf H; Scadden, David T; Lin, Charles P; Lapidot, Tsvee

    2016-04-21

    Bone marrow endothelial cells (BMECs) form a network of blood vessels that regulate both leukocyte trafficking and haematopoietic stem and progenitor cell (HSPC) maintenance. However, it is not clear how BMECs balance these dual roles, and whether these events occur at the same vascular site. We found that mammalian bone marrow stem cell maintenance and leukocyte trafficking are regulated by distinct blood vessel types with different permeability properties. Less permeable arterial blood vessels maintain haematopoietic stem cells in a low reactive oxygen species (ROS) state, whereas the more permeable sinusoids promote HSPC activation and are the exclusive site for immature and mature leukocyte trafficking to and from the bone marrow. A functional consequence of high permeability of blood vessels is that exposure to blood plasma increases bone marrow HSPC ROS levels, augmenting their migration and differentiation, while compromising their long-term repopulation and survival. These findings may have relevance for clinical haematopoietic stem cell transplantation and mobilization protocols. PMID:27074509

  20. Bone Marrow Diseases - Multiple Languages: MedlinePlus

    MedlinePlus

    ... Supplements Videos & Tools You Are Here: Home → Multiple Languages → All Health Topics → Bone Marrow Diseases URL of this page: https://www.nlm.nih.gov/medlineplus/languages/bonemarrowdiseases.html Other topics A-Z A B ...

  1. Red Spot Movie

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This brief movie shows counterclockwise atmospheric motion around Jupiter's Great Red Spot. The clip was made from blue-filter images taken with the narrow-angle camera on NASA's Cassini spacecraft during seven separate rotations of Jupiter between Oct. 1 and Oct. 5, 2000.

    The clip also shows the eastward and westward motion of the zonal jets, seen as the horizontal stripes flowing in opposite directions. The zonal jets circle the planet. As far as can be determined from both Earth-based and spacecraft measurements, the positions and speeds of the jets have not changed for 100 years. Since Jupiter is a fluid planet without a solid boundary, the jet speeds are measured relative to Jupiter's magnetic field, which rotates, wobbling like a top because of its tilt, every 9 hours 55.5 minutes. The movie shows motions in the magnetic reference frame, so winds to the west correspond to features that are rotating a little slower than the magnetic field, and eastward winds correspond to features rotating a little faster.

    Because the Red Spot is in the southern hemisphere, the direction of motion indicates it is a high-pressure center. Small bright clouds appear suddenly to the west of the Great Red Spot. Scientists suspect these small white features are lightning storms. The storms eventually merge with the Red Spot and surrounding jets, and may be the main energy source for the large-scale features.

    The smallest features in the movie are about 500 kilometers (about 300 miles) across. The spacing of the movie frames in time is not uniform; some consecutive images are separated by two Jupiter rotations, and some by one. The images have been re-projected using a simple cylindrical map projection. They show an area from 50 degrees north of Jupiter's equator to 50 degrees south, extending 100 degrees east-west, about one quarter of Jupiter's circumference.

    Cassini is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet

  2. Patient-Specific Dosimetry of Pretargeted Radioimmunotherapy Using CC49 Fusion Protein in Patients with Gastrointestinal Malignancies.

    SciTech Connect

    Shen, Shang; Forero, Andres; LoBuglio, Albert F.; Breitz, H; Khazaeli, M B.; Fisher, Darrell R.; Wang, W Q.; Meredith, Ruby F.

    2005-04-01

    Patient-Specific Dosimetry of Pretargeted Radioimmunotherapy Using CC49 Fusion Protein in Patients with Gastrointestinal Malignancies. Shen S, Forero A, Lobuglio AF, Breitz H, Khazaeli MB, Fisher DR, Wang W, Meredith RF. Department of Radiation Oncology, Comprehensive Cancer Center, University of Alabama at Birmingham, Birmingham, Alabama, and Radioisotopes Program at Pacific Northwest National Laboratory, Richland, Washington. Pretargeted radioimmunotherapy (RIT) using CC49 fusion protein, comprised of CC49-(scFv)(4) and streptavidin, in conjunction with (90)Y/(111)In-DOTA-biotin (DOTA = dodecanetetraacetic acid) provides a new opportunity to improve efficacy by increasing the tumor-to-normal tissue dose ratio. To our knowledge, the patient-specific dosimetry of pretargeted (90)Y/(111)In-DOTA-biotin after CC49 fusion protein in patients has not been reported previously. METHODS: Nine patients received 3-step pretargeted RIT: (a) 160 mg/m(2) of CC49 fusion protein, (b) synthetic clearing agent (sCA) at 48 or 72 h later, and (c) (90)Y/(111)In-DOTA-biotin 24 h after the sCA administration. Sequential whole-body (111)In images were acquired immediately and at 2-144 h after injection of (90)Y/(111)In-DOTA-biotin. Geometric-mean quantification with background and attenuation correction was used for liver and lung dosimetry. Effective point source quantification was used for spleen, kidneys, and tumors. Organ and tumor (90)Y doses were calculated based on (111)In imaging data and the MIRD formalism using patient-specific organ masses determined from CT images. Patient-specific marrow doses were determined based on radioactivity concentration in the blood. RESULTS: The (90)Y/(111)In-DOTA-biotin had a rapid plasma clearance, which was biphasic with <10% residual at 8 h. Organ masses ranged from 1,263 to 3,855 g for liver, 95 to 1,009 g for spleen, and 309 to 578 g for kidneys. The patient-specific mean (90)Y dose (cGy/37 MBq, or rad/mCi) was 0.53 (0.32-0.78) to whole body

  3. A marker chromosome in post-transplant bone marrow.

    PubMed

    Morsberger, Laura; Powell, Kerry; Ning, Yi

    2016-01-01

    Detection of small supernumerary marker chromosomes in karyotype analysis represents a diagnostic challenge. While such markers are usually detected during cytogenetic studies of constitutional chromosome abnormalities, they have also been found in specimens submitted from patients with acquired malignancies. We report here the detection of a marker chromosome in a bone marrow specimen from a patient who received a bone marrow transplantation. We discuss the importance of proper characterization and interpretation of marker chromosomes in clinical practice. PMID:27252781

  4. Memory T-cell competition for bone marrow seeding.

    PubMed

    Di Rosa, Francesca; Santoni, Angela

    2003-03-01

    The presence in the bone marrow of memory CD8 T cells is well recognized. However, it is still largely unclear how T-cell migration from the lymphoid periphery to the bone marrow is regulated. In the present report, we show that antigen-specific CD4 T cells, as well as antigen-specific CD8 T cells, localize to the bone marrow of immunized mice, and are sustained there over long periods of time. To investigate the rules governing T-cell migration to the bone marrow, we generated chimeric mice in which the lymphoid periphery contained two genetically or phenotypically distinct groups of T cells, one of which was identical to the host. We then examined whether a distinct type of T cell had an advantage over the others in the colonization of bone marrow. Our results show that whereas ICAM1 and CD18 molecules are both involved in homing to lymph nodes, neither is crucial for T-cell bone marrow colonization. We also observed that memory-phenotype CD44high T cells, but not virgin-type CD44-/low T cells, preferentially home to the bone marrow upon adoptive transfer to normal young mice, but not to thymectomized old recipients where an existing memory T-cell pool precludes their free access. Thus, T-cell colonization of the bone marrow uses distinct molecules from those implicated in lymph node homing, and is regulated both by the properties of the T cell and by the competitive efficacy of other T cells inhabiting the same, saturable niche. This implies that the homing potential of an individual lymphocyte is not merely an intrinsic property of the cell, but rather a property of the lymphoid system taken as a whole. PMID:12603595

  5. Bone Marrow Negative Visceral Leishmaniasis in an Adolescent Male

    PubMed Central

    Jetley, S; Rana, S; Khan, S; Zeeba, JS; Hassan, MJ; Kapoor, P

    2013-01-01

    Visceral Leishmaniasis or Kala Azar is endemic in certain regions of India. In endemic areas, the constellation of fever, progressive weight loss, weakness, pronounced splenomegaly, anemia, leukopenia, and hypergammaglobulinemia is highly suggestive of visceral leishmaniasis. Demonstration of the parasite in liver, splenic or bone marrow aspirates is confirmatory. We present a case in which Leishmania donovani (LD) bodies were demonstrated on splenic aspirate. We were unable to demonstrate LD bodies on bone marrow aspiration. PMID:23682278

  6. Pulmonary fat and bone marrow embolism in aircraft accident victims.

    PubMed

    Bierre, A R; Koelmeyer, T D

    1983-04-01

    On 28 November 1979, an Air New Zealand DC10 aircraft crashed into Mt Erebus, Antarctica with the loss of 257 passengers and crew. Postmortem examinations were carried out on 231 victims in Auckland, 4641 kilometres north of the crash site, and lung tissue was present in 205 cases. Pulmonary fat emboli were present in 134 cases (65%), pulmonary bone marrow emboli in 60 (29%) and pulmonary edema in 76 cases (37%). Clear relationships were demonstrated, firstly between the extent of fat and bone marrow embolism, secondly between the extent of fat and bone marrow embolism and the presence of pulmonary edema, and thirdly between the extent of fat and bone marrow embolism and the extent of cardiovascular damage. It was apparent that death had occurred immediately following impact, and the extent of fat and bone marrow embolism varied inversely with the severity of the injuries found. The most severely injured victims were those seated in the rear cabin of the aircraft suggesting that this was the site of impact with the ground. Our studies show that pulmonary fat embolism occurs very rapidly after severe injury and is followed by increasing numbers of fat and bone marrow emboli depending on the nature of the mortal injuries. PMID:6888959

  7. Bone scan appearances following bone and bone marrow biopsy

    SciTech Connect

    McKillop, J.H.; Maharaj, D.; Boyce, B.F.; Fogelman, I.

    1984-01-01

    Bone marrow and bone biopsies are performed not infrequently in patients referred for bone scans and represent a potential cause of a ''false positive'' focal abnormality on the bone scan. The authors have therefore examined the scan appearances in a series of patients who had undergone either sternal marrow biopsy, (Salah needle, diameter 1.2 mm) trephine iliac crest marrow biopsy (Jamshidi 11 gauge needle, diameter 3.5 mm) or a transiliac bone biopsy (needle diameter 8 mm). Of 18 patients studied 1 to 45 days after sternal marrow 17 had normal scan appearances at the biopsy site and 1 had a possible abnormality. None of 9 patients studied 4 to 19 days after trephine iliac crest marrow biopsy had a hot spot at the biopsy site. A focal scan abnormality was present at the biopsy site in 9/11 patients studied 5 to 59 days after a trans iliac bone biopsy. No resultant scan abnormality was seen in 4 patients imaged within 3 days of the bone biopsy or in 3 patients imaged 79 to 138 days after the procedure. Bone marrow biopsy of the sternum or iliac crest does not usually cause bone scan abnormalities. A focal abnormality at the biopsy site is common in patients imaged 5 days to 2 months after bone biopsy. The gauge of the needle employed in the biopsy and thus the degree of bone trauma inflicted, is likely to be main factor determining the appearance of bone scan abnormalities at the biopsy site.

  8. Activation of bone marrow phagocytes following benzene treatment of mice.

    PubMed Central

    Laskin, D L; MacEachern, L; Snyder, R

    1989-01-01

    Techniques in flow cytometry/cell sorting were used to characterize the effects of benzene and its metabolites on subpopulations of bone marrow cells. Treatment of male Balb/c mice with benzene (880 mg/kg) or a combination of its metabolites, hydroquinone and phenol (50 mg/kg), resulted in a 30 to 40% decrease in bone marrow cellularity. Flow cytometric analysis revealed two subpopulations of bone marrow cells that could be distinguished by their size and density or granularity. The larger, more dense subpopulation was found to consist predominantly of macrophages and granulocytes as determined by monoclonal antibody binding and by cell sorting. Benzene treatment had no selective cytotoxic effects on subpopulations of bone marrow cells. To determine if benzene treatment activated bone marrow phagocytes, we quantified production of hydrogen peroxide by these cells using the fluorescent indicator dye, 2',7'-dichlorofluorescein diacetate. We found that macrophages and granulocytes from bone marrow of treated mice produced 50% more hydrogen peroxide in response to the phorbol ester, 12-O-tetradecanoyl-phorbol-13-acetate than did cells from control animals. It is hypothesized that phagocyte activation and production of cytotoxic reactive oxygen intermediates may contribute to hematotoxicity induced by benzene. PMID:2676504

  9. Marrow fat metabolism is linked to the systemic energy metabolism

    PubMed Central

    Lecka-Czernik, Beata

    2011-01-01

    Recent advances in understanding the role of bone in the systemic regulation of energy metabolism indicate that bone marrow cells, adipocytes and osteoblasts, are involved in this process. Marrow adipocytes store significant quantities of fat and produce adipokines, leptin and adiponectin, which are known for their role in the regulation of energy metabolism, whereas osteoblasts produce osteocalcin, a bone-specific hormone that has a potential to regulate insulin production in the pancreas and adiponectin production in fat tissue. Both osteoblasts and marrow adipocytes express insulin receptor and respond to insulin-sensitizing anti-diabetic TZDs in a manner, which tightly links bone with the energy metabolism system. Metabolic profile of marrow fat resembles that of both, white and brown fat, which is reflected by its plasticity in acquiring different functions including maintenance of bone micro-environment. Marrow fat responds to physiologic and pathologic changes in energy metabolism status by changing volume and metabolic activity. This review summarizes available information on the metabolic function of marrow fat and provides hypothesis that this fat depot may acquire multiple roles depending on the local and perhaps systemic demands. These functions may include a role in bone energy maintenance and endocrine activities to serve osteogenesis during bone remodeling and bone healing. PMID:21757043

  10. Personnel neutron dosimetry improvements at Los Alamos National Laboratory

    SciTech Connect

    Harvey, W.F.; Hoffman, J.M.; Brake, R.J.; Bliss, J.L.

    1992-08-01

    We are investigating methods to improve neutron dosimetry at Los Alamos National Laboratory (LANL) using the track etch dosemeter CR-39. Specifically, use of CR-39 for dynamic environments, typically encountered at the LANL Plutonium Facility, is shown to be a superior method for personnel neutron dosimetry when compared to the currently used TLD system. The results of glovebox experiments simulating hydrogenous shielding used at LANL, temporal variations of neutron correction factors used at the Plutonium Facility, trial implementation at this facility and preliminary neutron spectroscopy measurements are presented and compared to reference dosimetry measurements. Our results confirm that use of a TLD system in a facility implementing hydrogenous shielding requires frequent field re-calibration. When such correction factors are not re-evaluated frequently, or are maintained at pre-shielding levels, significant (i.e., 2- to 3-fold) overestimation of the neutron dose equivalent can occur.

  11. Personnel neutron dosimetry improvements at Los Alamos National Laboratory

    SciTech Connect

    Harvey, W.F.; Hoffman, J.M.; Brake, R.J. ); Bliss, J.L. . Dept. of Nuclear Engineering)

    1992-01-01

    We are investigating methods to improve neutron dosimetry at Los Alamos National Laboratory (LANL) using the track etch dosemeter CR-39. Specifically, use of CR-39 for dynamic environments, typically encountered at the LANL Plutonium Facility, is shown to be a superior method for personnel neutron dosimetry when compared to the currently used TLD system. The results of glovebox experiments simulating hydrogenous shielding used at LANL, temporal variations of neutron correction factors used at the Plutonium Facility, trial implementation at this facility and preliminary neutron spectroscopy measurements are presented and compared to reference dosimetry measurements. Our results confirm that use of a TLD system in a facility implementing hydrogenous shielding requires frequent field re-calibration. When such correction factors are not re-evaluated frequently, or are maintained at pre-shielding levels, significant (i.e., 2- to 3-fold) overestimation of the neutron dose equivalent can occur.

  12. ASTM Standards for Reactor Dosimetry and Pressure Vessel Surveillance

    SciTech Connect

    GRIFFIN, PATRICK J.

    1999-09-14

    The ASTM standards provide guidance and instruction on how to field and interpret reactor dosimetry. They provide a roadmap towards understanding the current ''state-of-the-art'' in reactor dosimetry, as reflected by the technical community. The consensus basis to the ASTM standards assures the user of an unbiased presentation of technical procedures and interpretations of the measurements. Some insight into the types of standards and the way in which they are organized can assist one in using them in an expeditious manner. Two example are presented to help orient new users to the breadth and interrelationship between the ASTM nuclear metrology standards. One example involves the testing of a new ''widget'' to verify the radiation hardness. The second example involves quantifying the radiation damage at a pressure vessel critical weld location through surveillance dosimetry and calculation.

  13. [Electronic portal image device dosimetry for volumetric modulated arc therapy].

    PubMed

    Tatsumi, Daisaku; Nakada, Ryosei; Ienaga, Akinori; Yomoda, Akane; Inoue, Makoto; Ichida, Takao; Hosono, Masako

    2013-01-01

    Recently electronic portal image devices (EPIDs) have been widely used for quality assurance and dose verification. However there are no reports describing EPID dosimetry for Elekta volumetric modulated arc therapy (VMAT). We have investigated EPID dosimetry during VMAT delivery using a commercial software EPIDose with an Elekta Synergy linac. Dose rate dependence and the linac system sag during gantry rotation were measured. Gamma indices were calculated between measured doses using an EPID and calculation made by a treatment planning system for prostate VMAT test plans. The results were also compared to gamma indices using films and a two-dimensional detector array, MapCHECK2. The pass rates of the gamma analysis with a criterion of 3% and 2 mm for the three methods were over 96% with good consistency. Our results have showed that EPID dosimetry is feasible for Elekta VMAT. PMID:23358333

  14. Report from the dosimetry working group to CEDR project management

    SciTech Connect

    Fix, J J

    1994-08-01

    On August 2, 1989, Admiral Watkins, Secretary of the US Department of Energy (DOE), presented a four-point program designed to enhance the DOE epidemiology program. One part of this program was the establishment of a Comprehensive Epidemiologic Data Resource (CEDR) to facilitate independent research to validate and supplement DOE research on human health effects. A Dosimetry Working Group was formed during May 1991 to evaluate radiation dose variables and associated documentation that would be most useful to researchers for retrospective and prospective studies. The Working Group consisted of thirteen individuals with expertise and experience in health physics, epidemiology, dosimetry, computing, and industrial hygiene. A final report was delivered to CEDR Project Management during February 1992. The report contains a number of major recommendations concerning collection, interpretation, and documentation of dosimetry data to maximize their usefulness to researchers using CEDR for examining possible health effects of occupational exposure to ionizing radiation.

  15. Transplantation immunology: Solid Organ and bone marrow

    PubMed Central

    Chinen, Javier; Buckley, Rebecca H.

    2010-01-01

    Development of the field of organ and tissue transplantation has accelerated remarkably since the human major histocompatibility complex (MHC) was discovered in 1967. Matching of donor and recipient for MHC antigens has been shown to have a significant positive effect on graft acceptance. The roles of the different components of the immune system involved in the tolerance or rejection of grafts and in graft-versus-host disease have been clarified. These components include: antibodies, antigen presenting cells, helper and cytotoxic T cell subsets, immune cell surface molecules, signaling mechanisms and cytokines that they release. The development of pharmacologic and biological agents that interfere with the alloimmune response and graft rejection has had a crucial role in the success of organ transplantation. Combinations of these agents work synergistically, leading to lower doses of immunosuppressive drugs and reduced toxicity. Reports of significant numbers of successful solid organ transplants include those of the kidneys, liver, heart and lung. The use of bone marrow transplantation for hematological diseases, particularly hematological malignancies and primary immunodeficiencies, has become the treatment of choice in many of these conditions. Other sources of hematopoietic stem cells are also being used, and diverse immunosuppressive drug regimens of reduced intensity are being proposed to circumvent the mortality associated with the toxicity of these drugs. Gene therapy to correct inherited diseases by infusion of gene-modified autologous hematopoietic stem cells has shown efficacy in two forms of severe combined immunodeficiency, providing an alternative to allogeneic tissue transplantation. PMID:20176267

  16. Post-bone marrow transplant thrombotic microangiopathy.

    PubMed

    Obut, F; Kasinath, V; Abdi, R

    2016-07-01

    Thrombotic microangiopathy (TMA) is a systemic disease characterized by microangiopathic hemolytic anemia, thrombocytopenia and organ failure. Post-bone marrow transplant TMA (post-BMT TMA) is a life-threatening condition that has been reported to afflict between 0.5 and 63.6% of BMT patients. The incidence of post-BMT TMA is affected by evolving therapies such as conditioning regimens. The etiology of post-BMT TMA is thought to be multifactorial, including the effects of immunosuppressive agents, viral infections, TBI and GvHD. A growing body of evidence highlights the importance of complement system activation and endothelial damage in post-BMT TMA. Although plasmapheresis has commonly been used, its therapeutic rationale for the majority of post-BMT TMA cases is unclear in the absence of circulatory inhibitors. It has become possible to target complement activation with eculizumab, a drug that blocks the terminal complement pathway. Early studies have highlighted the importance of anti-complement therapies in treating post-BMT TMA. Moreover, finding complement gene mutations may identify patients at risk, but whether such patients benefit from prophylactic anti-complement therapies before BMT remains to be studied. This review focuses on diagnostic criteria, pathophysiology, treatment and renal outcomes of post-BMT TMA. PMID:26974272

  17. Endocrine complications following pediatric bone marrow transplantation.

    PubMed

    Ho, Josephine; Lewis, Victor; Guilcher, Gregory M T; Stephure, David K; Pacaud, Danièle

    2011-01-01

    Pediatric bone marrow transplantation (BMT) for various diseases can lead to endocrine system dysfunction owing to preparative regimens involving chemotherapy and radiation therapy. We assessed the prevalence of post-BMT endocrine complications in children treated at the Alberta Children's Hospital (ACH) from 1991 to 2001. Time of onset of endocrine dysfunction, underlying disease processes, chemotherapy, radiation therapy and age at BMT were characterized. Subjects of <18 years of age at the time of allogeneic or autologous BMT for whom 1-year follow-up through the ACH and a chart were available for review were included in the study. Subjects with a pre-existing endocrine condition were excluded. Of the 194 pediatric BMT procedures performed at the ACH between January 1, 1991 and December 31, 2001, 150 complete charts were available for review. Sixty five subjects received follow-up care at other centers and were excluded. Therefore, a total of 85 subjects were included in the review. The prevalence of endocrine complications identified was: primary hypothyroidism 1.2%, compensated hypothyroidism 7.0%, hyperthyroidism 2.4%, hypergonadotrophic hypogonadism 22.4%, abnormal bone density 2.4%, and secondary diabetes mellitus 1.2%. These findings emphasize the need to screen for endocrine system dysfunction, particularly hypergonadotrophic hypogonadism, in children who have undergone BMT. Children need long-term follow-up so that endocrine complications can be diagnosed and treated promptly. PMID:21823531

  18. Bone marrow cells other than stem cells seed the bone marrow after rescue transfusion of fatally irradiated mice

    SciTech Connect

    Cronkite, E.P.; Inoue, T.; Bullis, J.E.

    1987-12-01

    In a previous publication, iodinated deoxyuridine (/sup 125/IUdR) incorporation data were interpreted as indicating that spleen colony-forming units (CFU-S) in DNA synthesis preferentially seeded bone marrow. In the present studies, the CFU-S content of marrow from irradiated, bone-marrow transfused mice was directly determined. Pretreatment of the transfused cells with cytocidal tritiated thymidine resulted in an insignificant diminution in CFU-S content when compared with nontritiated thymidine pretreatment, implying that there is no preferential seeding. The /sup 125/IUdR incorporation data have been reinterpreted as being a result of the proliferation of other progenitor cells present that have seeded the bone marrow.

  19. Long-term survival of murine allogeneic bone marrow chimeras: effect of anti-lymphocyte serum and bone marrow dose

    SciTech Connect

    Norin, A.J.; Emeson, E.E.; Veith, F.J.

    1981-02-01

    Graft-vs-host disease (GVHD) and failure of donor stem cells to engraft permanently are two major obstacles to successful bone marrow transplantation. The effect of a single large dose of anti-lymphocyte serum (ALS) on mice receiving various numbers of H-2 incompatible bone marrow cells was evaluated. Most animals receiving lethal total body irradiation (TBI) and allogeneic marrow died within 45 days due to GVHD. Mice that were given ALS 6 to 24 h before TBI and bone marrow 24 h after irradiation survived in good health for more than 200 days. These cell preparations caused lethal GVHD in third party mice indicating that the lack of alloreactivity was specific to the strain in which the unresponsiveness was originally induced.

  20. Red - Take a Closer Look

    PubMed Central

    Buechner, Vanessa L.; Maier, Markus A.; Lichtenfeld, Stephanie; Schwarz, Sascha

    2014-01-01

    Color research has shown that red is associated with avoidance of threat (e.g., failure) or approach of reward (e.g., mating) depending on the context in which it is perceived. In the present study we explored one central cognitive process that might be involved in the context dependency of red associations. According to our theory, red is supposed to highlight the relevance (importance) of a goal-related stimulus and correspondingly intensifies the perceivers’ attentional reaction to it. Angry and happy human compared to non-human facial expressions were used as goal-relevant stimuli. The data indicate that the color red leads to enhanced attentional engagement to angry and happy human facial expressions (compared to neutral ones) - the use of non-human facial expressions does not bias attention. The results are discussed with regard to the idea that red induced attentional biases might explain the red-context effects on motivation. PMID:25254380