Radiation-induced soft-tissue and bone sarcoma

International Nuclear Information System (INIS)

Kim, J.H.; Chu, F.C.; Woodard, H.Q.; Melamed, R.; Huvos, A.; Cantin, J.

1978-01-01

From the records of Memorial Hospital of the past 50 years, 47 cases with an established diagnosis of radiation-induced sarcoma were identified and divided into two groups: the first included 20 cases of soft-tissue sarcoma arising from irradiated tissues, and the second comprised 27 cases of bone sarcoma arising from normal bones in the irradiated field. Medians for the latent periods from irradiation to diagnosis of bone and soft-tissue sarcoma were 11 and 12, years, respectively. In bone sarcomas, the latent period was longer after larger radiation doses and children appeared to be more susceptible to cancer induction than adults. Criteria for establishing the diagnosis of radiation-induced sarcoma and the magnitude of the risk of bone sarcoma are discussed

Radiation-induced pseudotumor following therapy for soft tissue sarcoma

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Moore, Lacey F.; Kransdorf, Mark J. [Mayo Clinic, Department of Radiology, Jacksonville, FL (United States); Buskirk, Steven J. [Mayo Clinic, Department of Radiation Oncology, Jacksonville, FL (United States); O' Connor, Mary I. [Mayo Clinic, Department of Orthopedic Surgery, Jacksonville, FL (United States); Menke, David M. [Mayo Clinic, Department of Pathology, Jacksonville, FL (United States)

2009-06-15

The purpose of this study was to describe the prevalence and imaging appearance of radiation induced pseudotumors in patients following radiation therapy for extremity soft tissue sarcomas. We retrospectively reviewed the serial magnetic resonance (MR) images of 24 patients following radiation therapy for extremity soft tissue sarcomas. A total of 208 exams were reviewed (mean, 8.7 exams per patient) and included all available studies following the start of radiation therapy. Exams were analyzed for the identification of focal signal abnormalities within the surgical bed suggesting local tumor recurrence. Histopathologic correlation was available in nine patients suspected of having local tumor recurrence. Additional information recorded included patient demographics, tumor type and location, radiation type, and dose. The study group consisted of 12 men and 12 women, having an average age of 63 years (range, 39-88 years). Primary tumors were malignant fibrous histiocytoma (n = 13), leiomyosarcoma (n = 6), liposarcoma (n = 3), synovial sarcoma (n = 1), and extraskeletal chondrosarcoma (n = 1). All lesions were high-grade sarcomas, except for two myxoid liposarcomas. Average patient radiation dose was 5,658 cGy (range, 4,500-8,040 cGy). Average follow-up time was 63 months (range, 3-204 months). Focal signal abnormalities suggesting local recurrence were seen in nine (38%) patients. Three of the nine patients with these signal abnormalities were surgically proven to have radiation-induced pseudotumor. The pseudotumors developed between 11 and 61 months following the initiation of radiation therapy (mean, 38 months), with an average radiation dose of 5,527 cGy (range, 5,040-6,500 cGy). MR imaging demonstrated a relatively ill-defined ovoid focus of abnormal signal and intense heterogeneous enhancement with little or no associated mass effect. MR imaging of radiation-induced pseudotumor typically demonstrates a relatively ill-defined ovoid mass-like focus of intense

Radiation sterilisation of tissue allografts for transplant surgery

International Nuclear Information System (INIS)

Phillips, G.O.

1994-01-01

The application of ionising radiation to sterilise biological tissues is an extension of their use for the sterilisation of other medical products and pharmaceuticals. This paper describes the effects of radiation on biological tissues, both at the macro- and molecular level. Changes in mechanical and other physical properties can accompany irradiation. These are shown to be due to the glycosamino-glycan component (hyaluronic acid), rather than to the collagen fibrils. Fast reaction methods are used to identify the mechanism of the radiation degradation processes. Methods by which tissues can be protected from these undesirable effects are discussed. The application of radiation sterilisation to human tissues used in transplant surgery is described, and the practical methods of processing given. Such radiation sterilised allografts now have wide application, with more than 500,000 used each year. The IAEA programme in this field has extended the application to 13 countries of the Asia and Pacific Region. Such Tissue Banks are also established with the support of IAEA in Africa and South America. The allografts can now be produced in developing countries in a readily available form, at low cost, and reduce the need for costly imported alternatives. (author). 45 refs., 19 figs., 3 tabs

Role of endothelium in radiation-induced normal tissue damages

International Nuclear Information System (INIS)

Milliat, F.

2007-05-01

More than half of cancers are treated with radiation therapy alone or in combination with surgery and/or chemotherapy. The goal of radiation therapy is to deliver enough ionising radiation to destroy cancer cells without exceeding the level that the surrounding healthy cells can tolerate. Unfortunately, radiation-induced normal tissue injury is still a dose limiting factor in the treatment of cancer with radiotherapy. The knowledge of normal tissue radiobiology is needed to determine molecular mechanisms involved in normal tissue pathogenic pathways in order to identify therapeutic targets and develop strategies to prevent and /or reduce side effects of radiation therapy. The endothelium is known to play a critical role in radiation-induced injury. Our work shows that endothelial cells promote vascular smooth muscle cell proliferation, migration and fibro-genic phenotype after irradiation. Moreover, we demonstrate for the first time the importance of PAI-1 in radiation-induced normal tissue damage suggesting that PAI-1 may represent a molecular target to limit injury following radiotherapy. We describe a new role for the TGF-b/Smad pathway in the pathogenesis of radiation-induced damages. TGF-b/Smad pathway is involved in the fibro-genic phenotype of VSMC induced by irradiated EC as well as in the radiation-induced PAI-1 expression in endothelial cells. (author)

Radiation-induced normal tissue damage: implications for radiotherapy

International Nuclear Information System (INIS)

Prasanna, Pataje G.

2014-01-01

Radiotherapy is an important treatment modality for many malignancies, either alone or as a part of combined modality treatment. However, despite technological advances in physical treatment delivery, patients suffer adverse effects from radiation therapy due to normal tissue damage. These side effects may be acute, occurring during or within weeks after therapy, or intermediate to late, occurring months to years after therapy. Minimizing normal tissue damage from radiotherapy will allow enhancement of tumor killing and improve tumor control and patients quality of life. Understanding mechanisms through which radiation toxicity develops in normal tissue will facilitate the development of next generation radiation effect modulators. Translation of these agents to the clinic will also require an understanding of the impact of these protectors and mitigators on tumor radiation response. In addition, normal tissues vary in radiobiologically important ways, including organ sensitivity to radiation, cellular turnover rate, and differences in mechanisms of injury manifestation and damage response. Therefore, successful development of radiation modulators may require multiple approaches to address organ/site-specific needs. These may include treatments that modify cellular damage and death processes, inflammation, alteration of normal flora, wound healing, tissue regeneration and others, specifically to counter cancer site-specific adverse effects. Further, an understanding of mechanisms of normal tissue damage will allow development of predictive biomarkers; however harmonization of such assays is critical. This is a necessary step towards patient-specific treatment customization. Examples of important adverse effects of radiotherapy either alone or in conjunction with chemotherapy, and important limitations in the current approaches of using radioprotectors for improving therapeutic outcome will be highlighted. (author)

Overview of Twenty Years of Radiation and Tissue Banking Activity in Argentina

International Nuclear Information System (INIS)

Kairiyama, E.

2015-01-01

Radiation sterilization of human tissues in Argentina was a consequence of health care products sterilization by gamma radiation. Radiation technology was implemented in 1970 when the first multipurpose gamma facility was built at the Ezeiza Atomic Centre of CNEA. Organ and tissue transplantation is a well established effective therapy that saves lives and significantly improves the quality of life. Ionizing radiation is used for sterilization in order to provide clinically safe tissue for therapeutic purposes of implantation in every patient in need. Argentina radiation and tissue banking activity started in 1993 with the establishment of two tissue banks using radiation under the IAEA programme of technical cooperation, a skin bank and a bone one. Additionally to this start, other tissue banks have adopted tissue sterilization by irradiation. The compatible tissues sterilized with this methodology are mainly skin (frozen, glycerolized), bone (lyophilized, frozen), and amniotic membrane (glycerolized, frozen, dehydrated). The donation and transplant of human organ, tissue and cells is regulated and coordinated by the National Institute Unique Central Coordinator of Ablation and Implant (INCUCAI). In regards to radiation and nuclear safety, physical protection and nuclear non-proliferation issues are regulated and contorted by the Nuclear Regulatory Authority (ARN). Eight tissue banks use gamma radiation for sterilization of human tissues (6 musculoskeletal, 1 skin and 1 amniotic membrane). Argentina has participated actively in several IAEA projects regarding radiation and tissue banking program, and it has been selected by the IAEA to host the Regional Training Centre for the Latin American region. The following activities were implemented: regional training courses in Buenos Aires, face to face (five) and virtual (four) modalities; collaboration on several materials related to tissue banking and radiation sterilization of tissue allograft, codes of practice for

Effects of ionizing radiation on plant tissue cultures

International Nuclear Information System (INIS)

Hell, K.G.

1978-01-01

A short review is done of the biological effects of ionizing radiations on plant tissues kept in culture, from the work of Gladys King, in 1949, with X-ray irradiated tobacco. The role of plant hormones is discussed in the processes of growth inhibition and growth restoration of irradiated tissues, as well as morphogenesis. Radioresistance of cells kept in culture and the use of ionizing radiations as mutagens are also commented. Some aspects of the biological effects of ionizing radiations that need to be investigated are discussed, and the problem of genome instability of plant tissues kept in culture is pointed out. (M.A.) [pt

Treatment Effects and Sequelae of Radiation Therapy for Orbital Mucosa-Associated Lymphoid Tissue Lymphoma

International Nuclear Information System (INIS)

Hata, Masaharu; Omura, Motoko; Koike, Izumi; Tomita, Naoto; Iijima, Yasuhito; Tayama, Yoshibumi; Odagiri, Kazumasa; Minagawa, Yumiko; Ogino, Ichiro; Inoue, Tomio

2011-01-01

Purpose: Among extranodal lymphomas, orbital mucosa-associated lymphoid tissue (MALT) lymphoma is a relatively rare presentation. We performed a review to ascertain treatment efficacy and toxicity of radiation therapy for orbital MALT lymphoma. We also evaluated changes in visual acuity after irradiation. Methods and Materials: Thirty patients with orbital MALT lymphoma underwent radiation therapy with curative intent. Clinical stages at diagnosis were stage I E A in 29 patients and stage II E A in 1 patient. Total doses of 28.8 to 45.8 Gy (median, 30 Gy) in 15 to 26 fractions (median, 16 fractions) were delivered to the tumors. Results: All irradiated tumors were controlled during the follow-up period of 2 to 157 months (median, 35 months) after treatment. Two patients had relapses that arose in the cervical lymph node and the ipsilateral palpebral conjunctiva outside the radiation field at 15 and 67 months after treatment, respectively. The 5-year local progression-free and relapse-free rates were 100% and 96%, respectively. All 30 patients are presently alive; the overall and relapse-free survival rates at 5 years were 100% and 96%, respectively. Although 5 patients developed cataracts of grade 2 at 8 to 45 months after irradiation, they underwent intraocular lens implantation, and their eyesight recovered. Additionally, there was no marked deterioration in the visual acuity of patients due to irradiation, with the exception of cataracts. No therapy-related toxicity of grade 3 or greater was observed. Conclusions: Radiation therapy was effective and safe for patients with orbital MALT lymphoma. Although some patients developed cataracts after irradiation, visual acuity was well preserved.

Treatment Effects and Sequelae of Radiation Therapy for Orbital Mucosa-Associated Lymphoid Tissue Lymphoma

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Hata, Masaharu, E-mail: mhata@syd.odn.ne.jp [Department of Radiology, Yokohama City University Graduate School of Medicine, Yokohama, Kanagawa (Japan); Omura, Motoko; Koike, Izumi [Department of Radiology, Yokohama City University Graduate School of Medicine, Yokohama, Kanagawa (Japan); Tomita, Naoto [Department of Internal Medicine and Clinical Immunology, Yokohama City University Graduate School of Medicine, Yokohama, Kanagawa (Japan); Iijima, Yasuhito [Department of Ophthalmology, Yokohama City University Graduate School of Medicine, Yokohama, Kanagawa (Japan); Tayama, Yoshibumi; Odagiri, Kazumasa; Minagawa, Yumiko [Department of Radiology, Yokohama City University Graduate School of Medicine, Yokohama, Kanagawa (Japan); Ogino, Ichiro [Department of Radiation Oncology, Yokohama City University Medical Center, Yokohama, Kanagawa (Japan); Inoue, Tomio [Department of Radiology, Yokohama City University Graduate School of Medicine, Yokohama, Kanagawa (Japan)

2011-12-01

Purpose: Among extranodal lymphomas, orbital mucosa-associated lymphoid tissue (MALT) lymphoma is a relatively rare presentation. We performed a review to ascertain treatment efficacy and toxicity of radiation therapy for orbital MALT lymphoma. We also evaluated changes in visual acuity after irradiation. Methods and Materials: Thirty patients with orbital MALT lymphoma underwent radiation therapy with curative intent. Clinical stages at diagnosis were stage I{sub E}A in 29 patients and stage II{sub E}A in 1 patient. Total doses of 28.8 to 45.8 Gy (median, 30 Gy) in 15 to 26 fractions (median, 16 fractions) were delivered to the tumors. Results: All irradiated tumors were controlled during the follow-up period of 2 to 157 months (median, 35 months) after treatment. Two patients had relapses that arose in the cervical lymph node and the ipsilateral palpebral conjunctiva outside the radiation field at 15 and 67 months after treatment, respectively. The 5-year local progression-free and relapse-free rates were 100% and 96%, respectively. All 30 patients are presently alive; the overall and relapse-free survival rates at 5 years were 100% and 96%, respectively. Although 5 patients developed cataracts of grade 2 at 8 to 45 months after irradiation, they underwent intraocular lens implantation, and their eyesight recovered. Additionally, there was no marked deterioration in the visual acuity of patients due to irradiation, with the exception of cataracts. No therapy-related toxicity of grade 3 or greater was observed. Conclusions: Radiation therapy was effective and safe for patients with orbital MALT lymphoma. Although some patients developed cataracts after irradiation, visual acuity was well preserved.

T lymphocytes and normal tissue responses to radiation

International Nuclear Information System (INIS)

Schaue, Dörthe; McBride, William H.

2012-01-01

There is compelling evidence that lymphocytes are a recurring feature in radiation damaged normal tissues, but assessing their functional significance has proven difficult. Contradictory roles have been postulated in both tissue pathogenesis and protection, although these are not necessarily mutually exclusive as the immune system can display what may seem to be opposing faces at any one time. While the exact role of T lymphocytes in irradiated normal tissue responses may still be obscure, their accumulation after tissue damage suggests they may be critical targets for radiotherapeutic intervention and worthy of further study. This is accentuated by recent findings that pathologically damaged “self,” such as occurs after exposure to ionizing radiation, can generate danger signals with the ability to activate pathways similar to those that activate adoptive immunity to pathogens. In addition, the demonstration of T cell subsets with their recognition radars tuned to “self” moieties has revolutionized our ideas on how all immune responses are controlled and regulated. New concepts of autoimmunity have resulted based on the dissociation of immune functions between different subsets of immune cells. It is becoming axiomatic that the immune system has the power to regulate radiation-induced tissue damage, from failure of regeneration to fibrosis, to acute and chronic late effects, and even to carcinogenesis. Our understanding of the interplay between T lymphocytes and radiation-damaged tissue may still be rudimentary but this is a good time to re-examine their potential roles, their radiobiological and microenvironmental influences, and the possibilities for therapeutic manipulation. This review will discuss the yin and yang of T cell responses within the context of radiation exposures, how they might drive or protect against normal tissue side effects and what we may be able do about it.

Tissue response after radiation exposure. Intestine

International Nuclear Information System (INIS)

Otsuka, Kensuke; Tomita, Masanori; Yamauchi, Motohiro; Iwasaki, Toshiyasu

2014-01-01

Gastrointestinal syndrome followed by 'gut death' is due to intestinal disorders. This syndrome is induced by high-dose (>10 Gy) of ionizing radiation. Recovery from the gastrointestinal syndrome would depend on the number of survived clonogens and regeneration capability of crypts. These tissue alterations can be observed by high-dose radiation, however, cellular dynamics in crypts can be affected by low-dose radiation. For example, Potten et al. found that low-dose radiation induce apoptosis of intestinal stem cells, which produce all differentiated function cells. Recently, intestinal stem cells are characterized by molecular markers such as Lgr5. Since intestinal adenomas can be induced by deletion of Apc gene in Lgr5 + stem cells, it is widely recognized that Lgr5 + stem cells are the cell-of-origin of cancer. Duodenal Lgr5 + stem cells are known as radioresistant cells, however, we found that ionizing radiation significantly induces the turnover of colonic Lgr5 + stem cells. Combined with the knowledge of other radioresistant markers, stem-cell dynamics in tissue after irradiation are becoming clear. The present review introduces the history of gastrointestinal syndrome and intestinal stem cells, and discusses those future perspectives. (author)

Adaptive Breast Radiation Therapy Using Modeling of Tissue Mechanics: A Breast Tissue Segmentation Study

International Nuclear Information System (INIS)

Juneja, Prabhjot; Harris, Emma J.; Kirby, Anna M.; Evans, Philip M.

2012-01-01

Purpose: To validate and compare the accuracy of breast tissue segmentation methods applied to computed tomography (CT) scans used for radiation therapy planning and to study the effect of tissue distribution on the segmentation accuracy for the purpose of developing models for use in adaptive breast radiation therapy. Methods and Materials: Twenty-four patients receiving postlumpectomy radiation therapy for breast cancer underwent CT imaging in prone and supine positions. The whole-breast clinical target volume was outlined. Clinical target volumes were segmented into fibroglandular and fatty tissue using the following algorithms: physical density thresholding; interactive thresholding; fuzzy c-means with 3 classes (FCM3) and 4 classes (FCM4); and k-means. The segmentation algorithms were evaluated in 2 stages: first, an approach based on the assumption that the breast composition should be the same in both prone and supine position; and second, comparison of segmentation with tissue outlines from 3 experts using the Dice similarity coefficient (DSC). Breast datasets were grouped into nonsparse and sparse fibroglandular tissue distributions according to expert assessment and used to assess the accuracy of the segmentation methods and the agreement between experts. Results: Prone and supine breast composition analysis showed differences between the methods. Validation against expert outlines found significant differences (P<.001) between FCM3 and FCM4. Fuzzy c-means with 3 classes generated segmentation results (mean DSC = 0.70) closest to the experts' outlines. There was good agreement (mean DSC = 0.85) among experts for breast tissue outlining. Segmentation accuracy and expert agreement was significantly higher (P<.005) in the nonsparse group than in the sparse group. Conclusions: The FCM3 gave the most accurate segmentation of breast tissues on CT data and could therefore be used in adaptive radiation therapy-based on tissue modeling. Breast tissue segmentation

Adaptive Breast Radiation Therapy Using Modeling of Tissue Mechanics: A Breast Tissue Segmentation Study

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Juneja, Prabhjot, E-mail: Prabhjot.Juneja@icr.ac.uk [Joint Department of Physics, Institute of Cancer Research, Sutton (United Kingdom); Harris, Emma J. [Joint Department of Physics, Institute of Cancer Research, Sutton (United Kingdom); Kirby, Anna M. [Department of Academic Radiotherapy, Royal Marsden National Health Service Foundation Trust, Sutton (United Kingdom); Evans, Philip M. [Joint Department of Physics, Institute of Cancer Research, Sutton (United Kingdom)

2012-11-01

Purpose: To validate and compare the accuracy of breast tissue segmentation methods applied to computed tomography (CT) scans used for radiation therapy planning and to study the effect of tissue distribution on the segmentation accuracy for the purpose of developing models for use in adaptive breast radiation therapy. Methods and Materials: Twenty-four patients receiving postlumpectomy radiation therapy for breast cancer underwent CT imaging in prone and supine positions. The whole-breast clinical target volume was outlined. Clinical target volumes were segmented into fibroglandular and fatty tissue using the following algorithms: physical density thresholding; interactive thresholding; fuzzy c-means with 3 classes (FCM3) and 4 classes (FCM4); and k-means. The segmentation algorithms were evaluated in 2 stages: first, an approach based on the assumption that the breast composition should be the same in both prone and supine position; and second, comparison of segmentation with tissue outlines from 3 experts using the Dice similarity coefficient (DSC). Breast datasets were grouped into nonsparse and sparse fibroglandular tissue distributions according to expert assessment and used to assess the accuracy of the segmentation methods and the agreement between experts. Results: Prone and supine breast composition analysis showed differences between the methods. Validation against expert outlines found significant differences (P<.001) between FCM3 and FCM4. Fuzzy c-means with 3 classes generated segmentation results (mean DSC = 0.70) closest to the experts' outlines. There was good agreement (mean DSC = 0.85) among experts for breast tissue outlining. Segmentation accuracy and expert agreement was significantly higher (P<.005) in the nonsparse group than in the sparse group. Conclusions: The FCM3 gave the most accurate segmentation of breast tissues on CT data and could therefore be used in adaptive radiation therapy-based on tissue modeling. Breast tissue

The treatment of late radiation effects with hyperbaric oxygenation (HBO)

International Nuclear Information System (INIS)

Plafki, C.; Carl, U.M.; Glag, M.; Hartmann, K.A.

1998-01-01

Background: Late radiation injuries may impose a negative influence on the quality of life in the affected patients. In several entities, standardized treatment protocols are lacking. Hyperbaric oxygenation (HBO) has been shown to have beneficial effects in the treatment of late radiation sequelae. Material and methods: The basic principles of HBO are reviewed as well as clinical issues. Current study protocols are presented. Results: During HBO-therapy the patient breathes pure oxygen at pressures above 100 kPa. The oxygen solubility within the fluid phase of the blood is largely increased. Biological effects include an increased oxygen diffusibility, improved collagen synthesis and neoangiogenesis as well as an enhancement of antimicrobial defenses. By decreasing the capillary filtration pressure a reduction of edema becomes possible. HBO has been shown to prevent complications following surgery in irradiated tissues. Its efficacy as an adjunct in the treatment of osteonecroses in radiation patients could be demonstrated. In addition, the loss of osseointegrated implants in the maxillofacial bones of these patients could be significantly reduced. Further indications include soft tissue necroses, hemorrhagic cystitis and proctitis in tumor patients that have been treated by radiotherapy as part of a multimodality approach. Conclusions: HBO in the treatment of late radiation effects is still subject of investigation, but remarkable results have been reported. Optimized treatment protocols need to be determined in various entities. The rate of side effects is acceptable low. (orig.) [de

Models for radiation-induced tissue degeneration and conceptualization of rehabilitation of irradiated tissue by cell therapy

International Nuclear Information System (INIS)

Phulpin, Berengere

2011-01-01

Radiation therapy induced acute and late sequelae within healthy tissue included in the irradiated area. In general, lesions are characterized by ischemia, cell apoptosis and fibrosis. In this context, cell therapy using bone marrow mesenchymal stem cells (BMSC) might represent an attractive new therapeutic approach, based partly on their angiogenic ability and their involvement in the natural processes of tissue repair. The first part of this work consisted in the development of experimental mouse model of radio-induced tissue degeneration similar to that occurring after radiotherapy. The aim was to better understand the physiopathological mechanisms of radiation-induced tissue damage and to determine the best treatment strategy. The second part of this work investigated the feasibility of autologous BMSC therapy on the murine model of radiation previously established with emphasis on two pre-requisites: the retention of the injected cells within the target tissue and the evaluation of the graft on bone metabolism. This preclinical investigation in a mouse model constitutes an essential step allowing an evaluation of the benefit of cell therapy for the treatment of radiation-induced tissue injury. Data from these studies could allow the proposal of clinical studies [fr

Radiation-associated breast tumors display a distinct gene expression profile

DEFF Research Database (Denmark)

Broeks, Annegien; Braaf, Linde M; Wessels, Lodewyk F A

2010-01-01

PURPOSE: Women who received irradiation for Hodgkin's lymphoma have a strong increased risk for developing breast cancer. Approximately 90% of the breast cancers in these patients can be attributed to their radiation treatment, rendering such series extremely useful to determine whether a common...... radiation-associated cause underlies the carcinogenic process. METHODS AND MATERIALS: In this study we used gene expression profiling technology to assess gene expression changes in radiation-associated breast tumors compared with a set of control breast tumors of women unexposed to radiation, diagnosed...... at the same age. RNA was obtained from fresh frozen tissue samples from 22 patients who developed breast cancer after Hodgkin's lymphoma (BfHL) and from 20 control breast tumors. RESULTS: Unsupervised hierarchical clustering of the profile data resulted in a clustering of the radiation-associated tumors...

Necrose de canto medial associado a hanseníase virchowiana: relato de caso

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Leiser Franco

2010-12-01

Full Text Available O caso em relato aborda uma etiologia rara para necrose de canto medial da pálpebra com comprometimento do sistema canalicular em uma paciente em tratamento para hanseníase virchowiana. O exame histopatológico da lesão necrótica evidenciou reação inflamatória granulomatosa com acúmulo de histiócitos e presença de bacilos álcool-ácido resistentes. Após tratamento medicamentoso a paciente apresentou uma evolução favorável com recuperação espontânea da arquitetura do canto medial, porém com destruição total do sistema canalicular.

Mechanisms of radiation-induced normal tissue toxicity and implications for future clinical trials

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Kim, Jae Ho; Jenrow, Kenneth A.; Brown, Stephen L. [Dept.of Radiation Oncology, Henry Ford Health System, Detroit (United States)

2014-09-15

To summarize current knowledge regarding mechanisms of radiation-induced normal tissue injury and medical countermeasures available to reduce its severity. Advances in radiation delivery using megavoltage and intensity-modulated radiation therapy have permitted delivery of higher doses of radiation to well-defined tumor target tissues. Injury to critical normal tissues and organs, however, poses substantial risks in the curative treatment of cancers, especially when radiation is administered in combination with chemotherapy. The principal pathogenesis is initiated by depletion of tissue stem cells and progenitor cells and damage to vascular endothelial microvessels. Emerging concepts of radiation-induced normal tissue toxicity suggest that the recovery and repopulation of stromal stem cells remain chronically impaired by long-lived free radicals, reactive oxygen species, and pro-inflammatory cytokines/chemokines resulting in progressive damage after radiation exposure. Better understanding the mechanisms mediating interactions among excessive generation of reactive oxygen species, production of pro-inflammatory cytokines and activated macrophages, and role of bone marrow-derived progenitor and stem cells may provide novel insight on the pathogenesis of radiation-induced injury of tissues. Further understanding the molecular signaling pathways of cytokines and chemokines would reveal novel targets for protecting or mitigating radiation injury of tissues and organs.

Mechanisms of radiation-induced normal tissue toxicity and implications for future clinical trials

International Nuclear Information System (INIS)

Kim, Jae Ho; Jenrow, Kenneth A.; Brown, Stephen L.

2014-01-01

To summarize current knowledge regarding mechanisms of radiation-induced normal tissue injury and medical countermeasures available to reduce its severity. Advances in radiation delivery using megavoltage and intensity-modulated radiation therapy have permitted delivery of higher doses of radiation to well-defined tumor target tissues. Injury to critical normal tissues and organs, however, poses substantial risks in the curative treatment of cancers, especially when radiation is administered in combination with chemotherapy. The principal pathogenesis is initiated by depletion of tissue stem cells and progenitor cells and damage to vascular endothelial microvessels. Emerging concepts of radiation-induced normal tissue toxicity suggest that the recovery and repopulation of stromal stem cells remain chronically impaired by long-lived free radicals, reactive oxygen species, and pro-inflammatory cytokines/chemokines resulting in progressive damage after radiation exposure. Better understanding the mechanisms mediating interactions among excessive generation of reactive oxygen species, production of pro-inflammatory cytokines and activated macrophages, and role of bone marrow-derived progenitor and stem cells may provide novel insight on the pathogenesis of radiation-induced injury of tissues. Further understanding the molecular signaling pathways of cytokines and chemokines would reveal novel targets for protecting or mitigating radiation injury of tissues and organs.

MRI appearance of radiation-induced changes of normal cervical tissues

International Nuclear Information System (INIS)

Noemayr, A.; Lell, M.; Bautz, W.; Sweeney, R.; Lukas, P.

2001-01-01

Irradiation causes specific MRI changes in anatomic morphology and signal intensity. To avoid misinterpretation, it is important to consider the potential radiation changes of normal tissue in MRI. The aim of this study was to describe the detected radiation effects on normal cervical tissues in MRI. Pretreatment and posttreatment MRI of 52 patients with primary neck tumors were evaluated retrospectively. The MR imaging was performed before initiating radiotherapy and at the end of the treatment period. Patients underwent follow-up studies within 24 months after the end of irradiation. Edema was the main radiation-induced effect. It was detected in the epiglottis, larynx, pharynx wall, retro- and parapharyngeal space, salivary glands, muscles, and subcutaneous tissue. In some cases the bone marrow of the mandible showed edema, due to osteonecrosis. We additionally detected fluid accumulation in the mastoid cells. Radiation caused volume reduction of the parotid gland, thickening of the pharynx wall, and fatty degeneration of bone marrow. Magnetic resonance imaging is an excellent method of depicting radiation-induced changes of normal tissue. Especially T2-weighted sequences allow the detection of even slight edema. It is important to be aware of the most common radiation-induced changes in MRI and to take them into account when assessing an examination. (orig.)

Contribution to the pathogenesis of radiation-induced injury to large arteries

International Nuclear Information System (INIS)

Zidar, Nina; Ferluga, Dusan; Hvala, Asta; Popovic, Mara; Soba, Erika

1997-01-01

We report a case of a 35-year-old man who died of a brain infarct 20 months after radiotherapy for carcinoma of the tonsil with metastases to the cervical lymph nodes. Histology revealed mild atherosclerosis, necrotizing vasculitis, and occlusive thrombosis of the internal carotid artery. Significant changes were observed in the vasa vasorum; swelling and detachment of the endothelium, subendothelial oedema, hyaline change, fibrinoid necrosis of the vessel walls with mononuclear cellular infiltration, accompanied by focal haemorrhages and chronic inflammation in the periadventitial soft tissue. We believe that these changes of the vasa vasorum and necrotizing vasculitis are causally related and that vasculitis represents focal ischaemic necroses with inflammatory reaction. Our findings support the hypothesis, based on experimental studies, that injury to the vasa vasorum is an important mechanism in the development of radiation-induced vasculopathy of large arteries. They also suggest an evolution of the injury to the vasa vasorum and periadventitial tissue from the early lesions described in our patient, to late stages resulting in dense periadventitial fibrosis as reported previously. We suggest that injury to the vasa vasorum and the consequent ischaemic lesions of the arterial wall are morphological features distinguishing radiation-induced arterial injury from spontaneous atherosclerosis. (author)

Resistência parcial à necrose dos frutos em genótipos de café arábica Partial resistance to fruit necrosis in arabic coffee genotypes

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Gustavo Hiroshi Sera

2009-01-01

Full Text Available Neste trabalho, objetivou-se identificar em genótipos de café arábica (Coffea arabica L. fontes de resistência à necrose de frutos em condições de campo. As variáveis resistência à necrose de frutos ("NF", quantidade média de frutos por nó produtivo ("FN" e índice de luminosidade dentro da copa da planta ("LUM" foram avaliadas em ensaio de campo no IAPAR (Londrina, em dezembro de 2004, em cafeeiros com três anos de idade. Foi avaliada a variável "NF", atribuindo notas de 1 a 5 sendo 1 para plantas com 0 % a 5 % de frutos necrosados. "FN" foi avaliada seguindo uma escala de notas de 1 a 5, onde 1 representa plantas com 0 a 3 frutos/ nó e nota 5 com mais do que 15 frutos/ nó. A avaliação da variável "LUM" foi visual e seguiu as notas de 1 a 5, onde 1 representa plantas com pouca luminosidade dentro da copa da planta. Dos 19 genótipos avaliados, 2 apresentaram moderada resistência, 7 moderada suscetibilidade, 5 suscetíveis e 5 altamente suscetíveis. As cultivares Obatã IAC 1669-20 e Catucaí Vermelho 4-79 apresentaram o melhor nível de resistência parcial de campo, ou seja, com moderada resistência à necrose de frutos associada ao Colletotrichum spp.The aim of this research was to identify in Coffea arabica L. coffee genotypes resistance sources to fruit necrosis in field conditions. The variables fruit necrosis ("NF", fruits per productive nodes average ("FN" and luminosity index inside of the plant canopy ("LUM" were evaluated in field assay at IAPAR (Londrina, in December 2004 on three years old coffee trees. The "NF" variable were evaluated attributing scores from 1 to 5, where score 1 represented plants with 0 to 5 % of necrosed fruits. "FN" were evaluated following a score scale from 1 to 5, where score 1 represented plants with 0 to 3 fruits/ node and score 5 with more than 15 fruits/ node. The evaluation of the variable "LUM" was visual and followed the scores from 1 to 5, where score 1 represented plants with

Chapter 8. Ionisation radiation and human organism. Radioactivity of human tissues

International Nuclear Information System (INIS)

Toelgyessy, J.; Harangozo, M.

2000-01-01

This is a chapter of textbook of radioecology for university students. In this chapter authors deal with ionisation radiation and human organism as well as with radioactivity of human tissues. Chapter consists of next parts: (1) Radiation stress of human organism; (2) Radioactivity of human tissues and the factors influencing radioactive contamination; (3) Possibilities of decreasing of radiation stress

Thermomechanical effect of pulse-periodic laser radiation on cartilaginous and eye tissues

Science.gov (United States)

Baum, O. I.; Zheltov, G. I.; Omelchenko, A. I.; Romanov, G. S.; Romanov, O. G.; Sobol, E. N.

2013-08-01

This paper is devoted to theoretical and experimental studies into the thermomechanical action of laser radiation on biological tissues. The thermal stresses and strains developing in biological tissues under the effect of pulse-periodic laser radiation are theoretically modeled for a wide range of laser pulse durations. The models constructed allow one to calculate the magnitude of pressures developing in cartilaginous and eye tissues exposed to laser radiation and predict the evolution of cavitation phenomena occurring therein. The calculation results agree well with experimental data on the growth of pressure and deformations, as well as the dynamics of formation of gas bubbles, in the laser-affected tissues. Experiments on the effect of laser radiation on the trabecular region of the eye in minipigs demonstrated that there existed optimal laser irradiation regimens causing a substantial increase in the hydraulic permeability of the radiation-exposed tissue, which can be used to develop a novel glaucoma treatment method.

Thermomechanical effect of pulse-periodic laser radiation on cartilaginous and eye tissues

International Nuclear Information System (INIS)

Baum, O I; Omelchenko, A I; Sobol, E N; Zheltov, G I; Romanov, G S; Romanov, O G

2013-01-01

This paper is devoted to theoretical and experimental studies into the thermomechanical action of laser radiation on biological tissues. The thermal stresses and strains developing in biological tissues under the effect of pulse-periodic laser radiation are theoretically modeled for a wide range of laser pulse durations. The models constructed allow one to calculate the magnitude of pressures developing in cartilaginous and eye tissues exposed to laser radiation and predict the evolution of cavitation phenomena occurring therein. The calculation results agree well with experimental data on the growth of pressure and deformations, as well as the dynamics of formation of gas bubbles, in the laser-affected tissues. Experiments on the effect of laser radiation on the trabecular region of the eye in minipigs demonstrated that there existed optimal laser irradiation regimens causing a substantial increase in the hydraulic permeability of the radiation-exposed tissue, which can be used to develop a novel glaucoma treatment method. (paper)

Radiation-induced hypoxia may perpetuate late normal tissue injury

International Nuclear Information System (INIS)

Vujaskovic, Zeljko; Anscher, Mitchell S.; Feng, Q.-F.; Rabbani, Zahid N.; Amin, Khalid; Samulski, Thaddeus S.; Dewhirst, Mark W.; Haroon, Zishan A.

2001-01-01

Purpose: The purpose of this study was to determine whether or not hypoxia develops in rat lung tissue after radiation. Methods and Materials: Fisher-344 rats were irradiated to the right hemithorax using a single dose of 28 Gy. Pulmonary function was assessed by measuring the changes in respiratory rate every 2 weeks, for 6 months after irradiation. The hypoxia marker was administered 3 h before euthanasia. The tissues were harvested at 6 weeks and 6 months after irradiation and processed for immunohistochemistry. Results: A moderate hypoxia was detected in the rat lungs at 6 weeks after irradiation, before the onset of functional or histopathologic changes. The more severe hypoxia, that developed at the later time points (6 months) after irradiation, was associated with a significant increase in macrophage activity, collagen deposition, lung fibrosis, and elevation in the respiratory rate. Immunohistochemistry studies revealed an increase in TGF-β, VEGF, and CD-31 endothelial cell marker, suggesting a hypoxia-mediated activation of the profibrinogenic and proangiogenic pathways. Conclusion: A new paradigm of radiation-induced lung injury should consider postradiation hypoxia to be an important contributing factor mediating a continuous production of a number of inflammatory and fibrogenic cytokines

A Combined Tissue Kinetics and Dosimetric Model of Respiratory Tissue Exposed to Radiation

Energy Technology Data Exchange (ETDEWEB)

John R. Ford

2005-11-01

Existing dosimetric models of the radiation response of tissues are essentially static. Consideration of changes in the cell populations over time has not been addressed realistically. For a single acute dose this is not a concern, but for modeling chronic exposures or fractionated acute exposures, the natural turnover and progression of cells could have a significant impact on a variety of endpoints. This proposal addresses the shortcomings of current methods by combining current dose-based calculation techniques with information on the cell turnover for a model tissue. The proposed model will examine effects at the single-cell level for an exposure of a section of human bronchiole. The cell model will be combined with Monte Carlo calculations of doses to cells and cell nuclei due to varying dose-rates of different radiation qualities. Predictions from the model of effects on survival, apoptosis rates, and changes in the number of cycling and differentiating cells will be tested experimentally. The availability of dynamic dosimetric models of tissues at the single-cell level will be useful for analysis of low-level radiation exposures and in the development of new radiotherapy protocols.

The establishment of animal model of radiation-skin-burn and its changes of tissue metabolism

International Nuclear Information System (INIS)

Lu Xingan; Wu Shiliang; Wang Xiuzhen; Zhou Yinghui; Feng Yizhong; Tian Ye; Peng Miao

2001-01-01

The biochemistry metabolic changes of the tissues induced by 60 Co γ radiation or by accelerator β radiation on the animal local tissues were observed. The experiment results were shown as follows: (1) 60 Co γ radiation can induce the metabolic changes of the local tissue and led to ulcer or death. (2) Accelerator β radiation at the same dose of γ radiation can only produce ulcer but no death. (3) The biochemistry metabolic changes of the tissues induced by 60 Co γ radiation are similar to that by β radiation, but as a radiation-burn animal model, the latter is better

Kinetics of radiation-induced apoptosis in neonatal urogenital tissues with and without protein synthesis inhibition

International Nuclear Information System (INIS)

Gobe, G.C.; Harmon, B.; Schoch, E.; Allan, D.J.

1996-01-01

The difference in incidence of radiation-induced apoptosis between two neonatal urogenital tissues, kidney and testis, was analysed over a 24h period. Concurrent administration of cycloheximide (10mg/kg body weight), a protein synthesis inhibitor, with radiation treatment was used to determine whether new protein synthesis had a role in induction of apoptosis in this in vivo model. Many chemotherapeutic drugs act via protein synthesis inhibition, and we believe that the results of this latter analysis may provide information for the planning of concurrent radio and chemotherapy. Apoptosis was quantified using morphological parameters, and verified by DNA gel electrophoresis for the typical banding pattern, and by electron microscopy. The proliferative index in tissues was studied, using [6- 3 H]-thymidine uptake ( 1h prior to euthanasia and collection of tissues) and autoradiography as indicators of cell proliferation (S-phase). Tissue was collected 2, 4, 6, 8, and 24h after radiation treatment. Expression of one of the apoptosis-associated genes, Bcl-2 (an apoptosis inhibitor/cell survival gene), was studied using immunohistochemistry. Apoptosis peaked at 4h in the testis and 6h in the kidney, emphasising the necessity of knowing tissue differences in radiation response if comparing changes at a particular time. A higher proportion (almost five fold) of the apoptotic cells died in S-phase in the kidney than the testis, over the 24h. Protein synthesis inhibition completely negated induction of apoptosis in both tissues. Necrosis was not identified at any time. Cycloheximide treatment greatly diminished Bcl-2 expression. The differences in response of the two tissues to irradiation relates to their innate cell (genetic) controls, which may be determined by their state of differentiation at time of treatment, or the tissue type. This in vivo study also suggests the model may be useful for analysis of other cancer therapies for example polychemotherapies or chemo

Tissue misrepair hypothesis for radiation carcinogenesis

International Nuclear Information System (INIS)

Kondo, Sohei

1991-01-01

Dose-response curves for chronic leukemia in A-bomb survivors and liver tumors in patients given Thorotrast (colloidal thorium dioxide) show large threshold effects. The existence of these threshold effects can be explained by the following hypothesis. A high dose of radiation causes a persistent wound in a cellrenewable tissue. Disorder of the injured cell society partly frees the component cells from territorial restraints on their proliferation, enabling them to continue development of their cellular functions toward advanced autonomy. This progression might be achieved by continued epigenetic and genetic changes as a result of occasional errors in the otherwise concerted healing action of various endogeneous factors recruited for tissue repair. Carcinogenesis is not simply a single-cell problem but a cell-society problem. Therefore, it is not warranted to estimate risk at low doses by linear extrapolation from cancer data at high doses without knowledge of the mechanism of radiation carcinogenesis. (author) 57 refs

Non-Directional Radiation Spread Modeling and Non-Invasive Estimating the Radiation Scattering and Absorption Parameters in Biological Tissue

Directory of Open Access Journals (Sweden)

S. Yu. Makarov

2015-01-01

Full Text Available The article dwells on a development of new non-invasive measurement methods of optical parameters of biological tissues, which are responsible for the scattering and absorption of monochromatic radiation. It is known from the theory of radiation transfer [1] that for strongly scattering media, to which many biological tissues pertain, such parameters are parameters of diffusion approximation, as well as a scattering coefficient and an anisotropy parameter.Based on statistical modeling the paper examines a spread of non-directional radiation from a Lambert light beam with the natural polarization that illuminates a surface of the biological tissue. Statistical modeling is based on the Monte Carlo method [2]. Thus, to have the correct energy coefficient values of Fresnel reflection and transmission in simulation of such radiation by Monte Carlo method the author uses his finding that is a function of the statistical representation for the incidence of model photons [3]. The paper describes in detail a principle of fixing the power transmitted by the non-directional radiation into biological tissue [3], and the equations of a power balance in this case.Further, the paper describes the diffusion approximation of a radiation transfer theory, often used in simulation of radiation propagation in strongly scattering media and shows its application in case of fixing the power transmitted into the tissue. Thus, to represent an uneven power distribution is used an approximating expression in conditions of fixing a total input power. The paper reveals behavior peculiarities of solution on the surface of the biological tissue inside and outside of the incident beam. It is shown that the solution in the region outside of the incident beam (especially far away from it, essentially, depends neither on the particular power distribution across the surface, being a part of the tissue, nor on the refractive index of the biological tissue. It is determined only by

NMR imaging of cell phone radiation absorption in brain tissue

Science.gov (United States)

Gultekin, David H.; Moeller, Lothar

2013-01-01

A method is described for measuring absorbed electromagnetic energy radiated from cell phone antennae into ex vivo brain tissue. NMR images the 3D thermal dynamics inside ex vivo bovine brain tissue and equivalent gel under exposure to power and irradiation time-varying radio frequency (RF) fields. The absorbed RF energy in brain tissue converts into Joule heat and affects the nuclear magnetic shielding and the Larmor precession. The resultant temperature increase is measured by the resonance frequency shift of hydrogen protons in brain tissue. This proposed application of NMR thermometry offers sufficient spatial and temporal resolution to characterize the hot spots from absorbed cell phone radiation in aqueous media and biological tissues. Specific absorption rate measurements averaged over 1 mg and 10 s in the brain tissue cover the total absorption volume. Reference measurements with fiber optic temperature sensors confirm the accuracy of the NMR thermometry. PMID:23248293

Pathogenesis of Radiation effects in normal tissues and options for intervention

International Nuclear Information System (INIS)

Dorr, W.

2011-01-01

Full text: Early (acute) side-effects of radio(chemo)therapy are observed during or shortly after a course of radiotherapy. In contrast, late (chronic) side-effects become clinically manifest after latent times of months to many years. Early effects are usually found in tissues with a high proliferative activity that balances a permanent cell loss (turnover tissues), such as bone marrow, or mucosae of the intestinal tract. The symptoms are based on radiation-induced impairment of cell production, resulting in progressive cell depletion. Late radiation side-effects are basically found in all organs. In contrast to the development of early side-effects, the pathogenetic pathways of chronic side-effects are more complex. The dominating processes occur in the parenchyma of the organs (i.e. in the tissue-specific compartments) and in the connective and vascular tissue compartments. Regularly, the immune system (macrophages, mast cells) contributes to the tissue reaction. Late radiation sequelae, with few exceptions, are irreversible and progressive, with severity increasing with longer follow-up times. Therefore, the longer the survival times of the patients (i.e. the better radiation therapy) the higher is the number of patients at risk for late reactions. Early and late radiation effects are independent with regard to their pathogenesis and, in general, conclusions from the severity of early reactions on the risk of late effects cannot be drawn. However, interactions between early and chronic reactions can result in consequential late effects (CLE), when the early-responding tissue compartments (e.g. epithelia) have a protective function against mechanical and/or chemical exposure. Hence, cell depletion allows for secondary traumata to the target structures of the late sequelae, in addition to the direct effects of radiation. Consequential late effects have e.g. been demonstrated for intestine, urinary tract, oral mucosa and lung. Interventions in the 'tissular

High and Low LET Radiation Differentially Induce Normal Tissue Damage Signals

International Nuclear Information System (INIS)

Niemantsverdriet, Maarten; Goethem, Marc-Jan van; Bron, Reinier; Hogewerf, Wytse; Brandenburg, Sytze; Langendijk, Johannes A.; Luijk, Peter van; Coppes, Robert P.

2012-01-01

Purpose: Radiotherapy using high linear energy transfer (LET) radiation is aimed at efficiently killing tumor cells while minimizing dose (biological effective) to normal tissues to prevent toxicity. It is well established that high LET radiation results in lower cell survival per absorbed dose than low LET radiation. However, whether various mechanisms involved in the development of normal tissue damage may be regulated differentially is not known. Therefore the aim of this study was to investigate whether two actions related to normal tissue toxicity, p53-induced apoptosis and expression of the profibrotic gene PAI-1 (plasminogen activator inhibitor 1), are differentially induced by high and low LET radiation. Methods and Materials: Cells were irradiated with high LET carbon ions or low LET photons. Cell survival assays were performed, profibrotic PAI-1 expression was monitored by quantitative polymerase chain reaction, and apoptosis was assayed by annexin V staining. Activation of p53 by phosphorylation at serine 315 and serine 37 was monitored by Western blotting. Transfections of plasmids expressing p53 mutated at serines 315 and 37 were used to test the requirement of these residues for apoptosis and expression of PAI-1. Results: As expected, cell survival was lower and induction of apoptosis was higher in high -LET irradiated cells. Interestingly, induction of the profibrotic PAI-1 gene was similar with high and low LET radiation. In agreement with this finding, phosphorylation of p53 at serine 315 involved in PAI-1 expression was similar with high and low LET radiation, whereas phosphorylation of p53 at serine 37, involved in apoptosis induction, was much higher after high LET irradiation. Conclusions: Our results indicate that diverse mechanisms involved in the development of normal tissue damage may be differentially affected by high and low LET radiation. This may have consequences for the development and manifestation of normal tissue damage.

Characteristics of liver tissue for attenuate the gamma radiation

International Nuclear Information System (INIS)

Arcos P, A.; Rodriguez N, S.; Pinedo S, A.; Amador V, P.; Chacon R, A.; Vega C, H.R.

2005-01-01

It was determined the lineal attenuation coefficient of hepatic tissue before gamma radiation of a source of 137 Cs. When exposing organic material before X or gamma radiation fields, part of the energy of the photons is absorbed by the material, while another part crosses it without producing any effect. The quantity of energy that is absorbed is a measure of the dose that receives the material. The three main mechanisms by means of which the gamma rays interacting with the matter are: The Photoelectric Effect, the Compton dispersion and the Even production; the sum of these three processes is translated in the attenuation coefficient of the radiation. In this work we have used hepatic tissue of bovine, as substitute of the human hepatic tissue, and we have measured the lineal attenuation coefficient for photons of 0.662 MeV. Through a series of calculations we have determined the lineal attenuation coefficient for photons from 10 -3 to 10 -5 MeV and the measured coefficient was compared with the one calculated. (Author)

The Addition of Manganese Porphyrins during Radiation Inhibits Prostate Cancer Growth and Simultaneously Protects Normal Prostate Tissue from Radiation Damage

Directory of Open Access Journals (Sweden)

Arpita Chatterjee

2018-01-01

Full Text Available Radiation therapy is commonly used for prostate cancer treatment; however, normal tissues can be damaged from the reactive oxygen species (ROS produced by radiation. In separate reports, we and others have shown that manganese porphyrins (MnPs, ROS scavengers, protect normal cells from radiation-induced damage but inhibit prostate cancer cell growth. However, there have been no studies demonstrating that MnPs protect normal tissues, while inhibiting tumor growth in the same model. LNCaP or PC3 cells were orthotopically implanted into athymic mice and treated with radiation (2 Gy, for 5 consecutive days in the presence or absence of MnPs. With radiation, MnPs enhanced overall life expectancy and significantly decreased the average tumor volume, as compared to the radiated alone group. MnPs enhanced lipid oxidation in tumor cells but reduced oxidative damage to normal prostate tissue adjacent to the prostate tumor in combination with radiation. Mechanistically, MnPs behave as pro-oxidants or antioxidants depending on the level of oxidative stress inside the treated cell. We found that MnPs act as pro-oxidants in prostate cancer cells, while in normal cells and tissues the MnPs act as antioxidants. For the first time, in the same in vivo model, this study reveals that MnPs enhance the tumoricidal effect of radiation and reduce oxidative damage to normal prostate tissue adjacent to the prostate tumor in the presence of radiation. This study suggests that MnPs are effective radio-protectors for radiation-mediated prostate cancer treatment.

Histopathologic aspects of radiation effects on lymphatic tissues and malignancies

International Nuclear Information System (INIS)

Lushbaugh, C.C.; Swartzendruber, D.C.

1976-01-01

Morphologic study with the light microscope remains our most facile and rapid means of tissue identification, diagnosis and staging of diseases, and demonstration of radiation-induced and other toxic effects. The inadequacy of its use alone, however, for the solution of biologic problems is nowhere better illustrated than in such studies on lymphatic tissues as are reported in this symposium. Nearly every classical concept concerning lymphocyte biology and disease derived by morphologic methods has been challenged or disproved in recent years by applications of nonmorphologic technologies. Studies with light and electron microscopy in combination with cell-labeling techniques, histochemical methodology, virology, immunology, and radiation biology have corrected many of our misconceptions and provided unifying concepts of lymphatic-tissue structure and function which explain anew our observations of the past. For example, nearly everyone now accepts the biologic role of viruses in what once were considered radiation-caused neoplasms in rodents, although whether the role of radiation and other physical and chemical insults in human carcinogenesis is direct or indirect is still to be elucidated. Also, the exact relations that obtain between radiation and cancer induction via viruses even in well-studied rodent systems remain to be determined; and here morphologic studies continue to play an important integrating role for the multidisciplinary studies that are required

Localized Orbital Mucosa-Associated Lymphoma Tissue Lymphoma Managed With Primary Radiation Therapy: Efficacy and Toxicity

Energy Technology Data Exchange (ETDEWEB)

Goda, Jayant Sastri [Radiation Medicine Program, Princess Margaret Hospital, University of Toronto, Toronto, Ontario (Canada); Le, Lisa W. [Biostatistics, Princess Margaret Hospital, University of Toronto, Toronto, Ontario (Canada); Lapperriere, Normand J.; Millar, Barbara-Ann; Payne, David; Gospodarowicz, Mary K.; Wells, Woodrow; Hodgson, David C.; Sun, Alexander [Radiation Medicine Program, Princess Margaret Hospital, University of Toronto, Toronto, Ontario (Canada); Simpson, Rand [Ocular Oncology, Princess Margaret Hospital, University of Toronto, Toronto, Ontario (Canada); Tsang, Richard W., E-mail: richard.tsang@rmp.uhn.on.ca [Radiation Medicine Program, Princess Margaret Hospital, University of Toronto, Toronto, Ontario (Canada)

2011-11-15

Purpose: To evaluate the clinical outcomes and late effects of radiation therapy (RT) in localized primary orbital mucosa-associated lymphoma tissue (MALT) lymphoma (POML). Methods and Materials: From 1989 to 2007, 89 patients with Stage IE POML received RT. The median age was 56 years old. Sites involved conjunctiva (59 patients [66%]), lacrimal gland (20 patients [23%]), and soft tissue (10 patients [11%]). Megavoltage beam(s) was used in 91%, electrons in 7%, and orthovoltage in 2% of cases. The dose given was 25 Gy in 97% and 30 Gy in 3% of patients. Lens shielding was possible in 57% of patients. Results: The median follow-up was 5.9 years. Complete response or unconfirmed complete response was seen in 88 patients (99%). Relapse occurred in 22 patients (25%). First relapse sites were local (2 patients [9%]), in the contralateral orbit (5 patients [23%]), and distant (15 patients [68%]). The 7-year overall survival (OS), cause-specific survival (CSS), relapse-free survival (RFS), and local control (LC) rates were 91%, 96%, 64%, and 97%, respectively. Radiation-related late sequelae were documented in 40 patients (45%). Cataracts were observed in 22 patients (Grade 1 in 2 patients; Grade 3 in 20 patients). The incidence of Grade 3 cataract at 7 years was 25%. Other late sequelae (n = 28) were dry eye(s) (22 patients [Grade 1 in 14 patients; Grade 2 in 2 patients; Grade 3 in 2 patients; n/s in 4 patients), keratitis (3 patients), macular degeneration/cystoid edema (2 patients), and vitreous detachment (1 patient). Five patients developed Grade 3 noncataract late effects. Lens shielding reduced the incidence of Grade 3 cataract and all Grade {>=}2 late sequelae. Seventeen patients (16 with cataracts) underwent surgery; 23 patients were treated conservatively. The outcome for managing late effects was generally successful, with 30 patients completely improved, and 9 patients with persisting late sequelae (10%). Conclusions: POML responds favorably to moderate doses

Kinetics of radiation-induced apoptosis in neonatal urogenital tissues with and without protein synthesis inhibition

Energy Technology Data Exchange (ETDEWEB)

Gobe, G.C.; Harmon, B.; Schoch, E.; Allan, D.J. [Queensland Univ., St. Lucia, QLD (Australia). Dept. of Chemistry

1996-12-31

The difference in incidence of radiation-induced apoptosis between two neonatal urogenital tissues, kidney and testis, was analysed over a 24h period. Concurrent administration of cycloheximide (10mg/kg body weight), a protein synthesis inhibitor, with radiation treatment was used to determine whether new protein synthesis had a role in induction of apoptosis in this in vivo model. Many chemotherapeutic drugs act via protein synthesis inhibition, and we believe that the results of this latter analysis may provide information for the planning of concurrent radio and chemotherapy. Apoptosis was quantified using morphological parameters, and verified by DNA gel electrophoresis for the typical banding pattern, and by electron microscopy. The proliferative index in tissues was studied, using [6-{sup 3}H]-thymidine uptake ( 1h prior to euthanasia and collection of tissues) and autoradiography as indicators of cell proliferation (S-phase). Tissue was collected 2, 4, 6, 8, and 24h after radiation treatment. Expression of one of the apoptosis-associated genes, Bcl-2 (an apoptosis inhibitor/cell survival gene), was studied using immunohistochemistry. Apoptosis peaked at 4h in the testis and 6h in the kidney, emphasising the necessity of knowing tissue differences in radiation response if comparing changes at a particular time. A higher proportion (almost five fold) of the apoptotic cells died in S-phase in the kidney than the testis, over the 24h. Protein synthesis inhibition completely negated induction of apoptosis in both tissues. Necrosis was not identified at any time. Cycloheximide treatment greatly diminished Bcl-2 expression. The differences in response of the two tissues to irradiation relates to their innate cell (genetic) controls, which may be determined by their state of differentiation at time of treatment, or the tissue type. This in vivo study also suggests the model may be useful for analysis of other cancer therapies for example polychemotherapies or chemo

Variations on metabolic activities of legume tissues through radiation in tissue culture

International Nuclear Information System (INIS)

Batra, Amla

1977-01-01

Cell cultures from Arachis hypogaea L. cultivated in a modified medium developed by Murashige and Skoog (1962) showed vigorous qrowth after radiation treatment. Investigations on the effect of various sugars on the chlorophyll formation and growth of the irradiated tissues showed that sucrose was superior to maltose, glucose or fructose as a carbon source. Lactose and mannitol supported growth and development of chlorophyll to a less degree. On prolonging the cultures on a sugar free medium, the tissues failed to regain either growth or chlorophyll content. (author)

Variations on metabolic activities of legume tissues through radiation in tissue culture

Energy Technology Data Exchange (ETDEWEB)

Batra, A [Rajasthan Univ., Jaipur (India). Dept. of Botany

1977-12-01

Cell cultures from Arachis hypogaea L. cultivated in a modified medium developed by Murashige and Skoog (1962) showed vigorous qrowth after radiation treatment. Investigations on the effect of various sugars on the chlorophyll formation and growth of the irradiated tissues showed that sucrose was superior to maltose, glucose or fructose as a carbon source. Lactose and mannitol supported growth and development of chlorophyll to a less degree. On prolonging the cultures on a sugar free medium, the tissues failed to regain either growth or chlorophyll content.

Improved Survival With Radiation Therapy in High-Grade Soft Tissue Sarcomas of the Extremities: A SEER Analysis

International Nuclear Information System (INIS)

Koshy, Matthew; Rich, Shayna E.; Mohiuddin, Majid M.

2010-01-01

Purpose: The benefit of radiation therapy in extremity soft tissue sarcomas remains controversial. The purpose of this study was to determine the effect of radiation therapy on overall survival among patients with primary soft tissue sarcomas of the extremity who underwent limb-sparing surgery. Methods and Materials: A retrospective study from the Surveillance, Epidemiology, and End Results (SEER) database that included data from January 1, 1988, to December 31, 2005. A total of 6,960 patients constituted the study population. Overall survival curves were constructed using the Kaplan-Meir method and for patients with low- and high-grade tumors. Hazard ratios were calculated based on multivariable Cox proportional hazards models. Results: Of the cohort, 47% received radiation therapy. There was no significant difference in overall survival among patients with low-grade tumors by radiation therapy. In high-grade tumors, the 3-year overall survival was 73% in patients who received radiation therapy vs. 63% for those who did not receive radiation therapy (p < 0.001). On multivariate analysis, patients with high-grade tumors who received radiation therapy had an improved overall survival (hazard ratio 0.67, 95% confidence interval 0.57-0.79). In patients receiving radiation therapy, 13.5% received it in a neoadjuvant setting. The incidence of patients receiving neoadjuvant radiation did not change significantly between 1988 and 2005. Conclusions: To our knowledge, this is the largest population-based study reported in patients undergoing limb-sparing surgery for soft tissue sarcomas of the extremities. It reports that radiation was associated with improved survival in patients with high-grade tumors.

Chronic radiation effects on dental hard tissue (''radiation carries''). Classification and therapeutic strategies

International Nuclear Information System (INIS)

Groetz, K.A.; Brahm, R.; Al-Nawas, B.; Wagner, W.; Riesenbeck, D.; Willich, N.; Seegenschmiedt, M.H.

2001-01-01

Objectives: Since the first description of rapid destruction of dental hard tissues following head and neck radiotherapy 80 years ago, 'radiation caries' is an established clinical finding. The internationally accepted clinical evaluation score RTOG/EORTC however is lacking a classification of this frequent radiogenic alteration. Material and Methods: Medical records, data and images of radiation effects on the teeth of more than 1,500 patients, who underwent periradiotherapeutic care, were analyzed. Macroscopic alterations regarding the grade of late lesions of tooth crowns were used for a classification into 4 grades according to the RTOG/EORTC guidelines. Results: No early radiation effects were found by macroscopic inspection. In the first 90 days following radiotherapy 1/3 of the patients complained of reversible hypersensitivity, which may be related to a temporary hyperemia of the pulp. It was possible to classify radiation caries as a late radiation effect on a graded scale as known from RTOG/EORTC for other organ systems. This is a prerequisite for the integration of radiation caries into the international nomenclature of the RTOG/EORTC classification. Conclusions: The documentation of early radiation effects on dental hard tissues seems to be neglectable. On the other hand the documentation of late radiation effects has a high clinical impact. The identification of an initial lesion at the high-risk areas of the neck and incisal part of the tooth can lead to a successful therapy as a major prerequisite for orofacial rehabilitation. An internationally standardized documentation is a basis for the evaluation of the side effects of radiooncotic therapy as well as the effectiveness of protective and supportive procedures. (orig.) [de

Endocrine factors influencing radiation injury to central nervous tissue

International Nuclear Information System (INIS)

Aristizabal, S.A.; Boone, M.L.; Laguna, J.F.

1979-01-01

Corticosteroids have been shown experimentally to lower the tolerance of various normal tissues (lung, kidney, intestine) to irradiation. Pre-existing hypertension also modified the effect of irradiation on the rat spinal cord and brain. Hypercorticism and hypertension co-exist in patients with Cushing's disease. Although these patients are often approached therapeutically by irradiation, no reports concerning differences in the radiation sensitivity of nervous tissue between normal subjects (non-functioning pituitary adenomas) and those with hormonal imbalance and/or hypertension appear to be available. A comprehensive review of the literature revealed 14 patients with radiation damage to brain or to optic pathways following moderate doses for pituitary adenomas. Seven of the 14 patients (50%) had Cushing's disease. This apparent higher incidence of radiation injury is significant if we consider that less than 5% of all patients receiving irradiation for pituitary adenomas have Cushing's disease

Role of radiation therapy in management of patients with sarcoma of soft tissue

International Nuclear Information System (INIS)

Suit, Herman D.; Spiro, Ira J.

1995-01-01

Soft tissue sarcomas (STS) are malignant neoplasms arising from the mesenchymal connective and supporting tissues. These tumors occur at all anatomic sites within the body and are of many histologic subtypes. There are some 5600 newly diagnosed patients with STS per year. Epidemiological and etiologic factors, including the role of environmental carcinogens and radiation in the development of these tumors will be made. The role of several oncogenes and suppressor genes (e.g. Rb, p53, MDM2) and cytogenetic alterations will be reviewed. Consideration of the epidemiology and role of environmental carcinogens and radiation in the development of these tumors will be made. The natural history of these tumors will be described with reference to local invasion and spread to regional and distal sites. The evaluation of the patients suspected of having a sarcoma of soft tissue will then be considered including the relative roles of CT, MRI, PET, and US. The place of core needle biopsy, incisional biopsy or excisional biopsy for tumors at various sites and sizes will be addressed. The histopathologic subtype assessment of the tumor by standard H and E stains, immunohistochemistry, electron microscopy and cytogenetic studies will then be discussed. The principal role for radiation in the management of patients with sarcoma of soft tissue is in combination with surgery. This may be: 1) pre-operative and or post-operative use of external beam photons, electrons, and protons, and 2) intra-operative use of brachytherapy or intra-operative election beam techniques. Results of treatment with respect to local control, disease-free survival and overall survival will be considered for each of the various techniques with respect to size, grade, histologic type, surgical margin status, anatomic site, primary vs. recurrent disease. Similarly, the factors associated with delay in wound healing are to be considered and strategies to reduce wound morbidity. Functional outcome after limb

Ionizing radiation-induced cancers. Experimental and clinical data

International Nuclear Information System (INIS)

Joveniaux, Alain.

1978-03-01

This work attempts to give an idea of radiocarcinogenesis, both experimental and clinical. Experimentally the possibility of radio-induced cancer formation has considerable doctrinal importance since it proves without question the carcinogenetic effect of radiations, and also yields basis information on the essential constants implicated in its occurrence: need for a latency time varying with the animal species and technique used, but quite long in relation to the specific lifetime of each species; importance of a massive irradiation, more conducive to cancerisation as long as it produces no necroses liable to stop the formation of any subsequent neoplasia; finally, rarity of is occurrence. Clinically although the cause and effect relationship between treatment and cancer is sometimes difficult to establish categorically, the fact is that hundreds of particularly disturbing observations remain and from their number often emerges under well-defined circumstances, an undeniable clinical certainty. Most importantly these observation fix the criteria necessary for the possibility of a radioinduced cancer to arise, i.e: the notion of a prior irradiation; the appearance of a cancer in the irradiation area; serious tissue damage in relation with an excessive radiation dose; a long latency period between irradition and appearance of the cancer [fr

Management of locally recurrent soft-tissue sarcoma after prior surgery and radiation therapy

International Nuclear Information System (INIS)

Torres, Mylin A.; Ballo, Matthew T.; Butler, Charles E.; Feig, Barry W.; Cormier, Janice N.; Lewis, Valerae O.; Pollock, Raphael E.; Pisters, Peter W.; Zagars, Gunar K.

2007-01-01

Purpose: The aim of this study was to evaluate outcome and treatment toxicity after wide local re-excision (WLE), with or without additional radiation therapy, for patients with isolated first local recurrence of soft-tissue sarcoma arising within a previously irradiated field. Methods: A retrospective review was performed of 62 consecutive patients. All patients underwent prior resection and external beam radiation. For recurrent disease, 25 patients were treated with WLE alone, and 37 patients were treated with WLE and additional radiation (45- 64 Gy). In 33 patients, the radiation was delivered via an afterloaded brachytherapy, single-plane implant. Results: The 5-year disease specific and distant metastasis-free survival rates were 65% and 73%, respectively. Local control (LC) at 5 years was 51%, and on multivariate analysis, a positive surgical resection margin (p< 0.001) was associated with a lower rate of LC. Reirradiation was not associated with improved LC; however complications requiring outpatient or surgical management were more common in patients who had undergone reirradiation (80% vs. 17%, p < 0.001). Amputation was also more common in the subgroup of patients who underwent extremity reirradiation (35% with radiation vs. 11% without, p = 0.05), although only one amputation was performed to resolve a treatment complication. Conclusion: Conservative surgery alone results in LC in a minority of patients who have failed locally after previous excision and external beam radiation. Although selection biases and small patient numbers confound the analysis, local treatment intensification with additional radiation does not clearly improve outcome after surgical excision alone, and is associated with an increase in complications

Radiobiology in clinical radiation therapy - Part III: Normal tissue damage

International Nuclear Information System (INIS)

Travis, Elizabeth L.

1996-01-01

Objective: This is the third part of a course designed for residents in radiation oncology preparing for their boards. This part of the course will focus on the mechanisms underlying damage in normal tissues. Although conventional wisdom long held that killing and depletion of a critical cell(s) in a tissue was responsible for the later expression of damage, histopathologic changes in normal tissue can now be explained and better understood in terms of the new molecular biology. The concept that depletion of a single cell type is responsible for the observed histopathologic changes in normal tissues has been replaced by the hypothesis that damage results from the interaction of many different cell systems, including epithelial, endothelial, macrophages and fibroblasts, via the production of specific autocrine, paracrine and endocrine growth factors. A portion of this course will discuss the clinical and experimental data on the production and interaction of those cytokines and cell systems considered to be critical to tissue damage. It had long been suggested that interindividual differences in radiation-induced normal tissue damage was genetically regulated, at least in part. Both clinical and experimental data supported this hypothesis but it is the recent advances in human and mouse molecular genetics which have provided the tools to dissect out the genetic component of normal tissue damage. These data will be presented and related to the potential to develop genetic markers to identify sensitive individuals. The impact on clinical outcome of the ability to identify prospectively sensitive patients will be discussed. Clinically it is well-accepted that the volume of tissue irradiated is a critical factor in determining tissue damage. A profusion of mathematical models for estimating dose-volume relationships in a number of organs have been published recently despite the fact that little data are available to support these models. This course will review the

Accumulation of radium in ferruginous protein bodies formed in lung tissue. Association of resulting radiation hotspots with malignant mesothelioma and other malignancies

International Nuclear Information System (INIS)

Nakamura, Eizo; Makishima, Akio; Hagino, Kyoko; Okabe, Kazunori

2009-01-01

While exposure to fibers and particles has been proposed to be associated with several different lung malignancies including mesothelioma, the mechanism for the carcinogenesis is not fully understood. Along with mineralogical observation, we have analyzed forty-four major and trace elements in extracted asbestos bodies (fibers and proteins attached to them) with coexisting fiber-free ferruginous protein bodies from extirpative lungs of individuals with malignant mesothelioma. These observations together with patients' characteristics suggest that inhaled iron-rich asbestos fibers and dust particles, and excess iron deposited by continuous cigarette smoking would induce ferruginous protein body formation resulting in ferritin aggregates in lung tissue. Chemical analysis of ferruginous protein bodies extracted from lung tissues reveals anomalously high concentrations of radioactive radium, reaching millions of times higher concentration than that of seawater. Continuous and prolonged internal exposure to hotspot ionizing radiation from radium and its daughter nuclides could cause strong and frequent DNA damage in lung tissue, initiate different types of tumour cells, including malignant mesothelioma cells, and may cause cancers. (author)

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

Science.gov (United States)

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

2015-01-01

(SI unit for ionizing radiation dosage, i.e. one joule of radiation energy per one kilogram of matter)) to facilitate risk prediction. This risk has considerable uncertainty associated with it, and no acceptable model for projecting degenerative tissue risk is currently available. In particular, risk factors such as obesity, alcohol, and tobacco use can act as confounding factors that contribute to the large uncertainties. The PELs could be violated under certain scenarios, including following a large SPE (solar proton event) or long-term GCR (galactic cosmic ray) exposure. Specifically, for a Mars mission, the accumulated dose is sufficiently high that epidemiology data and preliminary risk estimates suggest a significant risk for cardiovascular disease. Ongoing research in this area is intended to provide the evidence base for accurate risk quantification to determine criticality for extended duration missions. Data specific to the space radiation environment must be compiled to quantify the magnitude of this risk to decrease the uncertainty in current PELs and to determine if additional protection strategies are required. New research results could lead to estimates of cumulative radiation risk from CNS and degenerative tissue diseases that, when combined with the cancer risk, may have major negative impacts on mission design, costs, schedule, and crew selection. The current report amends an earlier report (Human Research Program Requirements Document, HRP-47052, Rev. C, dated Jan 2009) in order to provide an update of evidence since 2009.

Low-Dose Radiation Treatment in Pulmonary Mucosa-Associated Lymphoid Tissue Lymphoma: A Plausible Approach? A Single-Institution Experience in 10 Patients

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Girinsky, Theodore, E-mail: girinsky@igr.fr [Department of Radiation Oncology, Institut Gustave Roussy, Villejuif (France); Paumier, Amaury [Department of Radiation Oncology, Institut Gustave Roussy, Villejuif (France); Ferme, Christophe; Hanna, Colette; Ribrag, Vincent [Department of Hematology, Institut Gustave Roussy, Villejuif (France); Leroy-Ladurie, Francois [Department of Thoracic Surgery, Centre Chirurgical Marie Lannelongue, Le Plessis Robinson (France); Ghalibafian, Mithra [Department of Radiation Oncology, Institut Gustave Roussy, Villejuif (France)

2012-07-01

Purpose: To propose an alternative approach for treatment of pulmonary marginal zone lymphoma, using a very small radiation dose (2 Multiplication-Sign 2 Gy) delivered exclusively to tumor sites. Methods and Materials: Patients had localized pulmonary mucosa-associated lymphoid tissue (MALT) lymphoma according to the World Health Organization classification. The 6-MV radiation treatments were delivered using tumor-limited fields, except in cases of diffuse bilateral involvement. Two daily fractions of 2 Gy were delivered to tumor-limited fields using a 6-MV linear accelerator. Results: Ten patients with pulmonary MALT lymphoma entered the study. All but 1 had localized tumor masses. The median follow-up was 56 months (range, 2-103 months). Complete remission or an unconfirmed complete remission was obtained in 60% of patients within the first 2 months, and two additional partial responses were converted into a long-term unconfirmed complete remission. All patients are well and alive, no local progression was observed, and the 5-year progression-free survival rate was 87.5% (95% confidence interval 49%-97%). Conclusions: Our results suggest that extremely low radiation doses delivered exclusively to tumor sites might be a treatment option in pulmonary MALT lymphoma.

Low-Dose Radiation Treatment in Pulmonary Mucosa-Associated Lymphoid Tissue Lymphoma: A Plausible Approach? A Single-Institution Experience in 10 Patients

International Nuclear Information System (INIS)

Girinsky, Theodore; Paumier, Amaury; Ferme, Christophe; Hanna, Colette; Ribrag, Vincent; Leroy-Ladurie, François; Ghalibafian, Mithra

2012-01-01

Purpose: To propose an alternative approach for treatment of pulmonary marginal zone lymphoma, using a very small radiation dose (2 × 2 Gy) delivered exclusively to tumor sites. Methods and Materials: Patients had localized pulmonary mucosa-associated lymphoid tissue (MALT) lymphoma according to the World Health Organization classification. The 6-MV radiation treatments were delivered using tumor-limited fields, except in cases of diffuse bilateral involvement. Two daily fractions of 2 Gy were delivered to tumor-limited fields using a 6-MV linear accelerator. Results: Ten patients with pulmonary MALT lymphoma entered the study. All but 1 had localized tumor masses. The median follow-up was 56 months (range, 2–103 months). Complete remission or an unconfirmed complete remission was obtained in 60% of patients within the first 2 months, and two additional partial responses were converted into a long-term unconfirmed complete remission. All patients are well and alive, no local progression was observed, and the 5-year progression-free survival rate was 87.5% (95% confidence interval 49%–97%). Conclusions: Our results suggest that extremely low radiation doses delivered exclusively to tumor sites might be a treatment option in pulmonary MALT lymphoma.

Lovastatin attenuates ionizing radiation-induced normal tissue damage in vivo

International Nuclear Information System (INIS)

Ostrau, Christian; Huelsenbeck, Johannes; Herzog, Melanie; Schad, Arno; Torzewski, Michael; Lackner, Karl J.; Fritz, Gerhard

2009-01-01

Background and purpose: HMG-CoA-reductase inhibitors (statins) are widely used lipid-lowering drugs. Moreover, they have pleiotropic effects on cellular stress responses, proliferation and apoptosis in vitro. Here, we investigated whether lovastatin attenuates acute and subchronic ionizing radiation-induced normal tissue toxicity in vivo. Materials and methods: Four hours to 24 h after total body irradiation (6 Gy) of Balb/c mice, acute pro-inflammatory and pro-fibrotic responses were analyzed. To comprise subchronic radiation toxicity, mice were irradiated twice with 2.5 Gy and analyses were performed 3 weeks after the first radiation treatment. Molecular markers of inflammation and fibrosis as well as organ toxicities were measured. Results: Lovastatin attenuated IR-induced activation of NF-κB, mRNA expression of cell adhesion molecules and mRNA expression of pro-inflammatory and pro-fibrotic marker genes (i.e. TNFα, IL-6, TGFβ, CTGF, and type I and type III collagen) in a tissue- and time-dependent manner. γH2AX phosphorylation stimulated by IR was not affected by lovastatin, indicating that the statin has no major impact on the induction of DNA damage in vivo. Radiation-induced thrombopenia was significantly alleviated by lovastatin. Conclusions: Lovastatin inhibits both acute and subchronic IR-induced pro-inflammatory and pro-fibrotic responses and cell death in normal tissue in vivo. Therefore, lovastatin might be useful for selectively attenuating acute and subchronic normal tissue damage caused by radiotherapy.

Radiosensitization In Vivo by Histone Deacetylase Inhibition with No Increase in Early Normal Tissue Radiation Toxicity.

Science.gov (United States)

Groselj, Blaz; Ruan, Jia-Ling; Scott, Helen; Gorrill, Jessica; Nicholson, Judith; Kelly, Jacqueline; Anbalagan, Selvakumar; Thompson, James; Stratford, Michael R L; Jevons, Sarah J; Hammond, Ester M; Scudamore, Cheryl L; Kerr, Martin; Kiltie, Anne E

2018-02-01

As the population ages, more elderly patients require radiotherapy-based treatment for their pelvic malignancies, including muscle-invasive bladder cancer, as they are unfit for major surgery. Therefore, there is an urgent need to find radiosensitizing agents minimally toxic to normal tissues, including bowel and bladder, for such patients. We developed methods to determine normal tissue toxicity severity in intestine and bladder in vivo , using novel radiotherapy techniques on a small animal radiation research platform (SARRP). The effects of panobinostat on in vivo tumor growth delay were evaluated using subcutaneous xenografts in athymic nude mice. Panobinostat concentration levels in xenografts, plasma, and normal tissues were measured in CD1-nude mice. CD1-nude mice were treated with drug/irradiation combinations to assess acute normal tissue effects in small intestine using the intestinal crypt assay, and later effects in small and large intestine at 11 weeks by stool assessment and at 12 weeks by histologic examination. In vitro effects of panobinostat were assessed by qPCR and of panobinostat, TMP195, and mocetinostat by clonogenic assay, and Western blot analysis. Panobinostat resulted in growth delay in RT112 bladder cancer xenografts but did not significantly increase acute (3.75 days) or 12 weeks' normal tissue radiation toxicity. Radiosensitization by panobinostat was effective in hypoxic bladder cancer cells and associated with class I HDAC inhibition, and protein downregulation of HDAC2 and MRE11. Pan-HDAC inhibition is a promising strategy for radiosensitization, but more selective agents may be more useful radiosensitizers clinically, resulting in fewer systemic side effects. Mol Cancer Ther; 17(2); 381-92. ©2017 AACR See all articles in this MCT Focus section, "Developmental Therapeutics in Radiation Oncology." ©2017 American Association for Cancer Research.

Correlação entre a necrose de frutos associada ao Colletotrichum spp. com as características frutos por nó e produtividade entre genótipos de café arábica Correlation between fruit necrosis associated to Colletotrichum spp. with the fruits per node and yield traits of arabic coffee

Directory of Open Access Journals (Sweden)

Gustavo Hiroshi Sera

2008-02-01

Full Text Available O fungo Colletotrichum spp. vem sendo associado à graves perdas para a cafeicultura brasileira. Objetivou-se neste trabalho verificar a existência de relação entre a variável necrose de frutos associada ao Colletotrichum spp. ("COL" com a quantidade média de frutos por nó produtivo ("FN" e com a produção ("PRD" em genótipos de café arábica. O ensaio de campo foi realizado no IAPAR (Londrina, PR, Brasil em dezembro de 2004 e em cafeeiros com três anos de idade. A variável "COL" foi avaliada atribuindo-se notas de 1 a 5, onde 1 representam plantas com 0 % a 5 % de frutos necrosados. "FN" foi avaliada seguindo uma escala de notas de 1 a 5, onde 1 representa plantas com 0 a 3 frutos/ nó e nota 5 com mais do que 15 frutos/ nó. A avaliação visual subjetiva da produção foi estimada em litros de frutos em estádio cereja, por planta. A correlação de Pearson foi estimada para avaliar a existência de associações entre as variáveis. Foram observadas correlações positivas e significativas a 1 % entre "COL" e "FN" e entre "COL" e "PRD". A necrose de frutos foi mais intensa em cafeeiros com mais produção e com mais frutos por nó produtivo. Sugere-se que a avaliação da resistência de campo à necrose dos frutos associada à presença de Colletotrichum spp. seja realizada em cafeeiros com alta produção e com alta quantidade de frutos por nó produtivo.Different fungi species of genus Colletotrichum has been associated with losses to the Brazilian coffee crop. The aim of this research was to evaluate the association between the variable fruit necrosis associated to Colletotrichum spp. ("COL" with the fruits per productive node average ("FN" and between "COL" and the yield ("PRD" in Coffea arabica L. genotypes. The field assay was evaluated at IAPAR (Londrina, PR, Brazil, in December 2004 and on coffee trees with three years old. The "COL" variable was evaluated attributing scores from 1 to 5, where score 1 represents plants

Evaluation of normal tissue responses to high-LET radiations

International Nuclear Information System (INIS)

Halnan, K.E.

1979-01-01

Clinical results presented have been analysed to evaluate normal tissue responses to high-LET radiations. Damage to brain, spinal cord, gut, skin, connective tissue and bone has occurred. A high RBE is probable for brain and possible for spinal cord and gut but other reasons for damage are also discussed. A net gain seems likely. Random controlled trials are advocated. (author)

Microdosimetric characterisation of radiation fields for modelling tissue response in radiotherapy

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He Wang

2014-02-01

Full Text Available Purpose: Our overall goal is the development of an approach to model tissue response to radiotherapy in which a tissue is viewed as a statistical ensemble of interacting cells. This involves characterisation of radiation fields on the spatial scale of subcellular structures. On this scale, the spatial distribution of radiation energy imparted to tissue is highly non-uniform and should be characterised in statistical terms. Microdosimetry provides a formalism developed for that purpose. This study addresses limitations of the standard microdosimetric approach to modelling tissue response by introducing two new characteristics that include additional information in a form convenient for this application.Methods: The standard microdosimetric approach is based on the concept of a sensitive volume (SV representing a target volume in the cell. It is considered in isolation from other SVs, implying that energy depositions in different SVs are statistically independent and that individual cells respond to radiation independent of each other. In this study, we examined the latter approximation through analysis of correlation functions. All calculations were performed with Geant4-DNA Monte Carlo code. Results: We found that for some realistic scenarios, spatial correlations of deposited energy can be significant. Two new characteristics of radiation fields are proposed. The first is the specific energy-volume histogram (zVH, which is a microscopic analogue of the dose-volume histogram. The second describes the probability distribution of deposited energies in two SVs without assuming statistical independence between the SVs. Numerical examples for protons and carbon ions of therapeutic energies are presented and discussed.Conclusion: We extended the microdosimetric approach to modelling tissue response by including additional important characteristics and presented them in a more conventional radiotherapy format

A Combined Tissue Kinetics and Dosimetric Model of Respiratory Tissue Exposed to Radiation. Final Technical Report

International Nuclear Information System (INIS)

John R. Ford

2005-01-01

Existing dosimetric models of the radiation response of tissues are essentially static. Consideration of changes in the cell populations over time has not been addressed realistically. For a single acute dose this is not a concern, but for modeling chronic exposures or fractionated acute exposures, the natural turnover and progression of cells could have a significant impact on a variety of endpoints. This proposal addresses the shortcomings of current methods by combining current dose-based calculation techniques with information on the cell turnover for a model tissue. The proposed model will examine effects at the single-cell level for an exposure of a section of human bronchiole. The cell model will be combined with Monte Carlo calculations of doses to cells and cell nuclei due to varying dose-rates of different radiation qualities. Predictions from the model of effects on survival, apoptosis rates, and changes in the number of cycling and differentiating cells will be tested experimentally. The availability of dynamic dosimetric models of tissues at the single-cell level will be useful for analysis of low-level radiation exposures and in the development of new radiotherapy protocols

Protective Effect of Pyruvate Against Radiation-Induced Damage in Collagenized Tissues

Science.gov (United States)

Griko, Y. V.; Yan, Xiaoli

2016-01-01

Exposure to high doses of ionizing radiation produces both acute and late effects on the collagenized tissues and have profound effects on wound healing. Because of the crucial practical importance for new radioprotective agents, our study has been focused on evaluation of the efficacy of non-toxic naturally occurring compounds to protect tissue integrity against high-dose gamma radiation. Here, we demonstrate that molecular integrity of collagen may serve as a sensitive biological marker for quantitative evaluation of molecular damage to collagenized tissue and efficacy of radioprotective agents. Increasing doses of gamma radiation (0-50kGy) result in progressive destruction of the native collagen fibrils, which provide a structural framework, strength, and proper milieu for the regenerating tissue. The strategy used in this study involved the thermodynamic specification of all structural changes in collagenized matrix of skin, aortic heart valve, and bone tissue induced by different doses and conditions of g-irradiation. This study describes a simple biophysical approach utilizing the Differential Scanning Calorimetry (DSC) to characterize the structural resistance of the aortic valve matrix exposed to different doses of g-irradiation. It allows us to identify the specific response of each constituent as well as to determine the influence of the different treatments on the characteristic parameters of protein structure. We found that pyruvate, a substance that naturally occurs in the body, provide significant protection (up to 80%) from biochemical and biomechanical damage to the collagenized tissue through the effective targeting of reactive oxygen species. The recently discovered role of pyruvate in the cell antioxidant defense to O2 oxidation, and its essential constituency in the daily human diet, indicate that the administration of pyruvate-based radioprotective formulations may provide safe and effective protection from deleterious effects of ionizing

Effects of gamma radiations on certain tissues of heteropneustes fossils bloch

International Nuclear Information System (INIS)

Purohit, R.K.; Rathore, N.; Ahluwalia, P.; Srivastava, M.; Gupta, M.L.

1992-01-01

In the present investigation effect of gamma radiation on certain tissues (kidney, stomach and gills) of Heteropneustes fossilis Bloch, an Indian Cat fish, were studied. The fish were irradiated with 10 Gy of gamma radiations at the dose rate of 1.60 Gy/minute from a 60 Co source. Five fish were autopsied at each post-irradiation time of 1,2,3,7,15 and 30 days. Radiation induced histopathology was observed in all the tissues studied. The radio lesions appeared on day-1 after exposure which became exaggerated on day-2 and 3. Signs of recovery were noticed on day-7 which progressed on day-15 and normal histology was observed on day-30. (author). 18 refs

CT manifestations of radiation-induced change in chest tissue

International Nuclear Information System (INIS)

Pagani, J.J.; Libshitz, H.I.

1982-01-01

The computed tomographic appearance of acute and chronic radiation change in the thorax is described. Acute radiation pneumonitis demonstrates patchy, confluent regions of increased pulmonary attenuation. Chronic changes include soft tissue density fibrotic changes that blend smoothly with the pleural surfaces and adjacent mediastinal structures. Also seen are bronchiectatic changes and distortion of normal intrathoracic anatomic relationships. Both the acute and chronic changes usually make linear lateral margins with adjacent aerated lung. Development of a discrete mass or focal cavitation after the radiation changes have become stable is suspect for recurrent tumor or infection

Experimental studies on interactions of radiation and cancer chemotherapeutic drugs in normal tissues and a solid tumour

International Nuclear Information System (INIS)

Maase, H. van der

1986-01-01

The interactions of radiation and seven cancer chemotherapeutic drugs have been investigated in four normal tissues and in a solid C 3 H mouse mammary carcinoma in vivo. The investigated drugs were adriamycin (ADM), bleomycin (BLM), cyclophosphamide (CTX), 5-fluorouracil (5-FU), methotrexate (MTX), mitomycin C (MM-C) and cis-diamminedichloroplatinum(II) (cis-DDP). The drugs enhanced the radiation response in most cases. However, signs of radioprotection was observed for CTX in skin and for MTX in haemopoietic tissue. The interval and the sequence of the two treatment modalities were of utmost importance for the normal tissue reactions. In general, the most serious interactions occurred when drugs were administered simultaneously with or a few hours before radiation. The radiation-modifying effect of the drugs deviated from this pattern in the haemopoietic tissue as the radiation response was most enhanced on drug administration 1-3 days after radiation. Enhancement of the radiation response was generally less pronounced in the tumour model than in the normal tissues. The combined drug-radiation effect was apparently less time-dependent in the tumour than in the normal tissues. (Auth.)

Acoustic radiation force due to arbitrary incident fields on spherical particles in soft tissue

Energy Technology Data Exchange (ETDEWEB)

Treweek, Benjamin C., E-mail: btreweek@utexas.edu; Ilinskii, Yurii A.; Zabolotskaya, Evgenia A.; Hamilton, Mark F. [Applied Research Laboratories, The University of Texas at Austin, P.O. Box 8029, Austin, TX 78713-8029 (United States)

2015-10-28

Acoustic radiation force is of interest in a wide variety of biomedical applications ranging from tissue characterization (e.g. elastography) to tissue treatment (e.g. high intensity focused ultrasound, kidney stone fragment removal). As tissue mechanical properties are reliable indicators of tissue health, the former is the focus of the present contribution. This is accomplished through an investigation of the acoustic radiation force on a spherical scatterer embedded in tissue. Properties of both the scatterer and the surrounding tissue are important in determining the magnitude and the direction of the force. As these properties vary, the force computation shows changes in magnitude and direction, which may enable more accurate noninvasive determination of tissue properties.

Side effects of ionizing radiation on healthy tissues and organs at risk

International Nuclear Information System (INIS)

Cosset, J.M.

2010-01-01

Ionizing radiations induce cell death, causing deterministic or stochastic side-effects. This paper briefly summarizes the biological mechanisms of early and late side-effects of ionizing radiations on healthy tissue. (author)

Affinity Labeling of Membrane Receptors Using Tissue-Penetrating Radiations

Directory of Open Access Journals (Sweden)

Franklin C. Wong

2013-01-01

Full Text Available Photoaffinity labeling, a useful in vivo biochemical tool, is limited when applied in vivo because of the poor tissue penetration by ultraviolet (UV photons. This study investigates affinity labeling using tissue-penetrating radiation to overcome the tissue attenuation and irreversibly label membrane receptor proteins. Using X-ray (115 kVp at low doses (<50 cGy or Rad, specific and irreversible binding was found on striatal dopamine transporters with 3 photoaffinity ligands for dopamine transporters, to different extents. Upon X-ray exposure (115 kVp, RTI-38 and RTI-78 ligands showed irreversible and specific binding to the dopamine transporter similar to those seen with UV exposure under other conditions. Similarly, gamma rays at higher energy (662 keV also affect irreversible binding of photoreactive ligands to peripheral benzodiazepine receptors (by PK14105 and to the dopamine (D2 membrane receptors (by azidoclebopride, respectively. This study reports that X-ray and gamma rays induced affinity labeling of membrane receptors in a manner similar to UV with photoreactive ligands of the dopamine transporter, D2 dopamine receptor (D2R, and peripheral benzodiazepine receptor (PBDZR. It may provide specific noninvasive irreversible block or stimulation of a receptor using tissue-penetrating radiation targeting selected anatomic sites.

Gustatory tissue injury in man: radiation dose response relationships and mechanisms of taste loss

International Nuclear Information System (INIS)

Mossman, K.L.

1986-01-01

In this report dose response data for gustatory tissue damage in patients given total radiation doses ranging from 3000 to 6000 cGy are presented. In order to evaluate direct radiation injury to gustatory tissues as a mechanism of taste loss, measurements of damage to specific taste structures in bovine and murine systems following radiation exposure in the clinical range are correlated to taste impairment observed in radiotherapy patients. (author)

Pelvic Normal Tissue Contouring Guidelines for Radiation Therapy: A Radiation Therapy Oncology Group Consensus Panel Atlas

Energy Technology Data Exchange (ETDEWEB)

Gay, Hiram A., E-mail: hgay@radonc.wustl.edu [Washington University School of Medicine, St Louis, MO (United States); Barthold, H. Joseph [Commonwealth Hematology and Oncology, Weymouth, MA (United States); Beth Israel Deaconess Medical Center, Boston, MA (Israel); O' Meara, Elizabeth [Radiation Therapy Oncology Group, Philadelphia, PA (United States); Bosch, Walter R. [Washington University School of Medicine, St Louis, MO (United States); El Naqa, Issam [Department of Radiation Oncology, McGill University Health Center, Montreal, Quebec (Canada); Al-Lozi, Rawan [Washington University School of Medicine, St Louis, MO (United States); Rosenthal, Seth A. [Radiation Oncology Centers, Radiological Associates of Sacramento, Sacramento, CA (United States); Lawton, Colleen [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, WI (United States); Lee, W. Robert [Department of Radiation Oncology, Duke University Medical Center, Durham, NC (United States); Sandler, Howard [Cedars-Sinai Medical Center, Los Angeles, CA (United States); Zietman, Anthony [Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States); Myerson, Robert [Washington University School of Medicine, St Louis, MO (United States); Dawson, Laura A. [Department of Radiation Oncology, Princess Margaret Hospital, University of Toronto, Toronto, Ontario (Canada); Willett, Christopher [Department of Radiation Oncology, Duke University Medical Center, Durham, NC (United States); Kachnic, Lisa A. [Department of Radiation Oncology, Boston Medical Center, Boston University School of Medicine, Boston, MA (United States); Jhingran, Anuja [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, TX (United States); Portelance, Lorraine [University of Miami, Miami, FL (United States); Ryu, Janice [Radiation Oncology Centers, Radiological Associates of Sacramento, Sacramento, CA (United States); and others

2012-07-01

Purpose: To define a male and female pelvic normal tissue contouring atlas for Radiation Therapy Oncology Group (RTOG) trials. Methods and Materials: One male pelvis computed tomography (CT) data set and one female pelvis CT data set were shared via the Image-Guided Therapy QA Center. A total of 16 radiation oncologists participated. The following organs at risk were contoured in both CT sets: anus, anorectum, rectum (gastrointestinal and genitourinary definitions), bowel NOS (not otherwise specified), small bowel, large bowel, and proximal femurs. The following were contoured in the male set only: bladder, prostate, seminal vesicles, and penile bulb. The following were contoured in the female set only: uterus, cervix, and ovaries. A computer program used the binomial distribution to generate 95% group consensus contours. These contours and definitions were then reviewed by the group and modified. Results: The panel achieved consensus definitions for pelvic normal tissue contouring in RTOG trials with these standardized names: Rectum, AnoRectum, SmallBowel, Colon, BowelBag, Bladder, UteroCervix, Adnexa{sub R}, Adnexa{sub L}, Prostate, SeminalVesc, PenileBulb, Femur{sub R}, and Femur{sub L}. Two additional normal structures whose purpose is to serve as targets in anal and rectal cancer were defined: AnoRectumSig and Mesorectum. Detailed target volume contouring guidelines and images are discussed. Conclusions: Consensus guidelines for pelvic normal tissue contouring were reached and are available as a CT image atlas on the RTOG Web site. This will allow uniformity in defining normal tissues for clinical trials delivering pelvic radiation and will facilitate future normal tissue complication research.

Ionizing radiation for sterilization of medical products and biological tissues

Energy Technology Data Exchange (ETDEWEB)

Kumar, S K; Raghevendrarao, M K [Bhabha Atomic Research Centre, Bombay (India). Library and Technical Information Section

1975-10-01

The article reviews the deliberations of the International Symposium on Ionizing Radiation for Sterilization of Medical Products and Biological Tissues which was held during 9-13 December 1974 under the auspices of the IAEA at the Bhabha Atomic Research Centre, Bombay. 42 papers were presented in the following broad subject areas: (1) Microbiological Control aspects of radiation sterilization, (2) Dosimetry aspects of radiation sterilization practices, (3) Effects of sterilizing radiation dose on the constituents of medical products, (4) Application of radiation sterilization of medical products of biological origin, (5) Technological aspects of radiation sterilization facilities, (6) Radiation sterilization of pharmaceutical substances, (7) Reports on current status of radiation sterilization of medical products in IAEA member states and (8) Working group discussion on the revision of the IAEA recommended code of practice for radiation sterilization of medical products.

Early Brain Response to Low-Dose Radiation Exposure Involves Molecular Networks and Pathways Associated with Cognitive Functions, Advanced Aging and Alzheimer's Disease

International Nuclear Information System (INIS)

Lowe, Xiu R.; Bhattacharya, Sanchita; Marchetti, Francesco; Wyrobek, Andrew J.

2008-01-01

Understanding the cognitive and behavioral consequences of brain exposures to low-dose ionizing radiation has broad relevance for health risks from medical radiation diagnostic procedures, radiotherapy, environmental nuclear contamination, as well as earth orbit and space missions. Analyses of transcriptome profiles of murine brain tissue after whole-body radiation showed that low-dose exposures (10 cGy) induced genes not affected by high dose (2 Gy), and low-dose genes were associated with unique pathways and functions. The low-dose response had two major components: pathways that are consistently seen across tissues, and pathways that were brain tissue specific. Low-dose genes clustered into a saturated network (p -53 ) containing mostly down-regulated genes involving ion channels, long-term potentiation and depression, vascular damage, etc. We identified 9 neural signaling pathways that showed a high degree of concordance in their transcriptional response in mouse brain tissue after low-dose radiation, in the aging human brain (unirradiated), and in brain tissue from patients with Alzheimer's disease. Mice exposed to high-dose radiation did not show these effects and associations. Our findings indicate that the molecular response of the mouse brain within a few hours after low-dose irradiation involves the down-regulation of neural pathways associated with cognitive dysfunctions that are also down regulated in normal human aging and Alzheimer's disease

Far-Infrared Radiation Thermotherapy Improves Tissue Fibrosis in Chronic Extremity Lymphedema.

Science.gov (United States)

Li, Ke; Zhang, Zheng; Liu, Ning Fei; Sadigh, Parviz; Evans, Verity Joyce; Zhou, Huihong; Gao, Weiqing; Zhang, Yi Xin

2017-09-29

Fibrosis can enhance the exacerbation of lymphedema, which becomes obvious in late stage II-III lymphedema. However, whether far-infrared radiation thermotherapy (FIRT) can cure lymphedema fibrosis is still lack of research. This research was to investigate the therapeutic effect of FIRT on tissue fibrosis in the treatment of Late stage II-III lymphedema. Patients accepted only FIRT for a total of 20 sessions. The treatment session duration was 2 hours, and a stable machine temperature of 42°C was maintained throughout treatments. Clinical evaluation and laboratory evaluation were conducted before and after FIRT. Clinical outcome measures included circumference of affected extremity, skin elasticity, ultrasound, patients' subjective assessment, and quality of life (QOL). Laboratory outcome measures included serum and local lymphedema tissue fluid concentrations of fibrosis associated cytokines, tissue growth factor beta-1 (TGF-β1), interleukin (IL)-1β, IL-4, IL-18, and caspase-1. Between 2015 and 2016, clinical evaluation of 64 patients with late stage II-III lymphedema was conducted. From this group, 12 cases (18.75%) underwent simultaneous laboratory evaluation. Circumferences of affected extremities improved significantly following treatment (p pain, discomfort, and numbness (p effective treatment for lymphedema tissue fibrosis; it reduces the concentration of fibrosis cytokines in local lymphedema tissues. Consequently, this treatment can reduce the density of fibrosed tissue in the affected extremity, increase skin elasticity, significantly improve clinical symptoms, and improve QOL of patients.

Optical and histological evaluation in human tendon tissue sterilized by ionizing radiation

Energy Technology Data Exchange (ETDEWEB)

Funari, Ana Paula; Antebi, Uri; Santos, Luiz Augusto; Vieira, Daniel Perez; Miranda, Jurandir Tomaz de; Alves, Nelson Mendes; Freitas, Anderson Zanardi de; Mathor, Monica Beatriz, E-mail: anapaulafunari@gmail.com, E-mail: mathor@ipen.br, E-mail: uri@usp.br, E-mail: luiz.santos@hc.fm.usp.br, E-mail: tomazdemiranda.j@gmail.com, E-mail: nelsonnininho@gmail.com [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Faculdade de Ciências Médicas da Santa Casa de São Paulo, SP (Brazil); Universidade de São Paulo (USP), SP (Brazil). Faculdade de Medicina; Universidade Federal de Santa Maria (UFSM), RS (Brazil)

2017-11-01

Sterilization by irradiation is a technique that is used by tissue banks aiming to eliminate contamination of human allografts, being a safe method, free of residue and used as final sterilization. After the tissue procurement, these undergo a series of processing stages and then are packaged and preserved by freezing. Despite aseptic care of the material those may be subjected to sterilization in the final packing by ionizing radiation, raising the security level of sterility of the tissue. The aim of this study was to evaluate the effects of application of ionizing radiation, produced by {sup 60}Co source in human tendons pre-processed (A-alcohol + antibiotic; B- H{sub 2}O{sub 2} + ultrasound) obtained through collaboration with tissue banks and preserved by freezing in -80° C, the radiation absorbed doses in processing were 12.5, 15 and 25 kGy, each one with their corresponding non-irradiated control, to examine possible structural or morphological alterations. The irradiated samples and their controls were analyzed by means of optical coherence tomography (OCT) and optical coherence tomography polarization sensitive (PS-OCT), and histological tests had been stained with hematoxylin-eosin (HE). According to the results the tissue processed with alcohol/antibiotic in conjunction with irradiation proved to be the most effective. (author)

Optical and histological evaluation in human tendon tissue sterilized by ionizing radiation

International Nuclear Information System (INIS)

Funari, Ana Paula; Antebi, Uri; Santos, Luiz Augusto; Vieira, Daniel Perez; Miranda, Jurandir Tomaz de; Alves, Nelson Mendes; Freitas, Anderson Zanardi de; Mathor, Monica Beatriz

2017-01-01

Sterilization by irradiation is a technique that is used by tissue banks aiming to eliminate contamination of human allografts, being a safe method, free of residue and used as final sterilization. After the tissue procurement, these undergo a series of processing stages and then are packaged and preserved by freezing. Despite aseptic care of the material those may be subjected to sterilization in the final packing by ionizing radiation, raising the security level of sterility of the tissue. The aim of this study was to evaluate the effects of application of ionizing radiation, produced by "6"0Co source in human tendons pre-processed (A-alcohol + antibiotic; B- H_2O_2 + ultrasound) obtained through collaboration with tissue banks and preserved by freezing in -80° C, the radiation absorbed doses in processing were 12.5, 15 and 25 kGy, each one with their corresponding non-irradiated control, to examine possible structural or morphological alterations. The irradiated samples and their controls were analyzed by means of optical coherence tomography (OCT) and optical coherence tomography polarization sensitive (PS-OCT), and histological tests had been stained with hematoxylin-eosin (HE). According to the results the tissue processed with alcohol/antibiotic in conjunction with irradiation proved to be the most effective. (author)

The use of normal tissue complication probability to predict radiation hepatitis

International Nuclear Information System (INIS)

Keum, Ki Chang; Seong, Jin Sil; Suh, Chang Ok; Lee, Sang Wook; Chung, Eun Ji; Shin, Hyun Soo; Kim, Gwi Eon

2000-01-01

Although it has been known that the tolerance of the liver to external beam irradiation depends on the irradiated volume and dose, few data exist which quantify this dependence. However, recently, with the development of three dimensional (3-D) treatment planning, have the tools to quantify the relationships between dose, volume, and normal tissue complications become available. The objective of this study is to investigate the relationships between normal tissue complication probability (NTCP) and the risk of radiation hepatitis for patients who received variant dose partial liver irradiation. From March 1992 to December 1994, 10 patients with hepatoma and 10 patients with bile duct cancer were included in this study. Eighteen patients had normal hepatic function, but 2 patients (prothrombin time 73%, 68%) had mild liver cirrhosis before irradiation. Radiation therapy was delivered with 10MV linear accelerator, 180-200 cGy fraction per day. The total dose ranged from 3,960 cGy to 6,000 cGy (median dose 5,040 cGy). The normal tissue complication probability was calculated by using Lyman's model. Radiation hepatitis was defined as the development of anicteric elevation of alkaline phosphatase of at least two fold and non-malignant ascites in the absence of documented progressive. The calculated NTCP ranged from 0.001 to 0.840 (median 0.05). Three of the 20 patients developed radiation hepatitis. The NTCP of the patients with radiation hepatitis were 0.390, 0.528, 0.844 (median: O.58±0.23), but that of the patients without radiation hepatitis ranged from 0.001 to 0.308 (median: 0.09±0.09). When the NTCP was calculated by using the volume factor of 0.32, a radiation hepatitis was observed only in patients with the NTCP value more than 0.39. By contrast, clinical results of evolving radiation hepatitis were not well correlated with NTCP value calculated when the volume factor of 0.69 was applied. On the basis of these observations, volume factor of 0.32 was more

A pilot study of the characterization of hepatic tissue strain in children with cystic-fibrosis-associated liver disease (CFLD) by acoustic radiation force impulse imaging

International Nuclear Information System (INIS)

Behrens, Christopher B.; Langholz, Juliane H.; Eiler, Jessika; Jenewein, Raphael; Fuchs, Konstantin; Alzen, Gerhard F.P.; Naehrlich, Lutz; Harth, Sebastian; Krombach, Gabriele A.

2013-01-01

Progressive fibrotic alterations of liver tissue represent a major complication in children with cystic fibrosis. Correct assessment of cystic-fibrosis-associated liver disease (CFLD) in clinical routine is a challenging issue. Sonographic elastography based on acoustic radiation force impulse imaging (ARFI) is a new noninvasive approach for quantitatively assessing in vivo elasticity of biological tissues in many organs. To characterize ARFI elastography as a diagnostic tool to assess alteration of liver tissue elasticity related to cystic fibrosis in children. ARFI elastography and B-mode US imaging were performed in 36 children with cystic fibrosis. The children's clinical history and laboratory parameters were documented. According to the findings on conventional US, children were assigned to distinct groups indicating severity of hepatic tissue alterations. The relationship between US findings and respective elastography values was assessed. Additionally, differences between ARFI elastography values of each US group were statistically tested. Children with sonomorphologic characteristics of fibrotic tissue remodeling presented significantly increased values for tissue elasticity. Children with normal B-mode US or discrete signs of hepatic tissue alterations showed a tendency toward increased tissue stiffness indicating early tissue remodeling. Assessment of children with CFLD by means of ARFI elastography yields adequate results when compared to conventional US. For detection of early stages of liver disease with mild fibrotic reactions of hepatic tissue, ARFI elastography might offer diagnostic advantages over conventional US. Thus, liver stiffness measured by means of elastography might represent a valuable biological parameter for evaluation and follow-up of CFLD. (orig.)

A pilot study of the characterization of hepatic tissue strain in children with cystic-fibrosis-associated liver disease (CFLD) by acoustic radiation force impulse imaging

Energy Technology Data Exchange (ETDEWEB)

Behrens, Christopher B.; Langholz, Juliane H.; Eiler, Jessika; Jenewein, Raphael; Fuchs, Konstantin; Alzen, Gerhard F.P. [University Hospital Giessen, Department of Pediatric Radiology, Giessen (Germany); Naehrlich, Lutz [University Hospital Giessen, Department of Pediatrics, Giessen (Germany); Harth, Sebastian; Krombach, Gabriele A. [University Hospital Giessen, Department of Radiology, Giessen (Germany)

2013-03-15

Progressive fibrotic alterations of liver tissue represent a major complication in children with cystic fibrosis. Correct assessment of cystic-fibrosis-associated liver disease (CFLD) in clinical routine is a challenging issue. Sonographic elastography based on acoustic radiation force impulse imaging (ARFI) is a new noninvasive approach for quantitatively assessing in vivo elasticity of biological tissues in many organs. To characterize ARFI elastography as a diagnostic tool to assess alteration of liver tissue elasticity related to cystic fibrosis in children. ARFI elastography and B-mode US imaging were performed in 36 children with cystic fibrosis. The children's clinical history and laboratory parameters were documented. According to the findings on conventional US, children were assigned to distinct groups indicating severity of hepatic tissue alterations. The relationship between US findings and respective elastography values was assessed. Additionally, differences between ARFI elastography values of each US group were statistically tested. Children with sonomorphologic characteristics of fibrotic tissue remodeling presented significantly increased values for tissue elasticity. Children with normal B-mode US or discrete signs of hepatic tissue alterations showed a tendency toward increased tissue stiffness indicating early tissue remodeling. Assessment of children with CFLD by means of ARFI elastography yields adequate results when compared to conventional US. For detection of early stages of liver disease with mild fibrotic reactions of hepatic tissue, ARFI elastography might offer diagnostic advantages over conventional US. Thus, liver stiffness measured by means of elastography might represent a valuable biological parameter for evaluation and follow-up of CFLD. (orig.)

Studies of ionising radiation induced bystander effects in 3D artificial tissue system and applications for radiation protection

International Nuclear Information System (INIS)

Belyakov, Oleg V.; Kuopio Univ.

2008-01-01

The universality of the target theory of radiation-induced effects is challenged by observations on non-targeted effects such as bystander effects. Essential features of non-targeted effects are that they do not require direct nuclear exposure by radiation and they are particularly significant at low doses. This new evidence suggests a need for a new paradigm in radiation biology. The new paradigm should cover both the classical (targeted) and the non-targeted effects. The bystander effect cannot be comprehensively explained on the basis of a single cell reaction. It is well known that an organism is composed of different cell types that interact as functional units in a way to maintain normal tissue function. Therefore the radiation response is not simply the sum of cellular responses as assumed in classical radiobiology, predominantly from studies using cell cultures. Experimental models, which maintain tissue-like intercellular cell signalling and 3D structure, are essential for proper understanding of the bystander effect. Our work relates to experimentation with novel 3D artificial human tissue systems available from MatTek Corporation (Boston, USA). Air-liquid interface culture technique is used to grow artificial tissues, which allow to model conditions present in vivo. The Gray Cancer Institute (Northwood, UK) charged particle microbeam was used to irradiate tissue samples in a known pattern with a known number of 3 He 2+ particles or protons. After irradiation, the tissues models were incubated for 3 days, fixed in 10 % NBF, paraffin embedded and then sliced into 5 μm histological sections located at varying distances from the plane of the irradiated cells. We studied in situ apoptosis and markers of differentiation. Significantly elevated bystander induced apoptosis was observed with 3'-OH DNA end-labelling based technique in 3D artificial tissue systems. Our results also suggested an importance of proliferation and differentiation status for bystander

Protective Effect of HSP25 on Radiation Induced Tissue Damage

International Nuclear Information System (INIS)

Lee, Hae-June; Lee, Yoon-Jin; Kwon, Hee-Choong; Bae, Sang-Woo; Lee, Yun-Sil; Kim, Sung Ho

2007-01-01

Control of cancer by irradiation therapy alone or in conjunction with combination chemotherapy is often limited by organ specific toxicity. Ionizing irradiation toxicity is initiated by damage to normal tissue near the tumor target and within the transit volume of radiotherapy beams. Irradiation-induced cellular, tissue, and organ damage is mediated by acute effects, which can be dose limiting. A latent period follows recovery from the acute reaction, then chronic irradiation fibrosis (late effects) pose a second cause of organ failure. HSP25/27 has been suggested to protect cells against apoptotic cell death triggered by hyperthermia, ionizing radiation, oxidative stress, Fas ligand, and cytotoxic drugs. And several mechanisms have been proposed to account for HSP27-mediated apoptotic protection. However radioprotective effect of HSP25/27 in vivo system has not yet been evaluated. The aim of this study was to evaluate the potential of exogenous HSP25 expression, as delivered by adenoviral vectors, to protect animal from radiation induced tissue damage

Role of radiation therapy in management of patients with sarcoma of soft tissue

International Nuclear Information System (INIS)

Spiro, Ira J.

1996-01-01

Soft tissue sarcomas (STS) are relatively rare malignant neoplasms arising from the mesenchymal connective tissues. There are some 5600 newly diagnosed patients with STS per year. These tumors occur at all anatomic sites within the body and are of many histologic subtypes. Etiologic factors, including occupational risks, the role of environmental carcinogens, radiation and genetic diseases in the development of these tumors will be mode. The molecular biology of soft tissue sarcomas including the role of several oncogenes and suppressor genes (e.g. Rb, p53, MDM2) will be reviewed. Cytogenetic alternations with an emphasis on molecular diagnostic techniques will be reviewed. The natural history of these tumors will be described with reference to local invasion and spread to regional and distal sites. The evaluation of the patients suspected of having a sarcoma of soft tissue will then be considered including the relative roles of various imaging modalities. The timing and type of biopsy (including FNA, core needle biopsy, incisional biopsy or excisional biopsy) for tumors at various sites and sizes will be addressed. Assessment of histopathologic subtype of the tumor by standard H and E stains, immunohistochemistry, electron microscopy and cytogenetic studies will then be discussed. The principal role for radiation in the management of patients with sarcoma of soft tissue is in combination with surgery. This may be: 1) pre-operative and or post-operative use of external beam photons, electrons, and protons, and 2) intra-operative use of electron beam techniques, or 3) post-operative brachytherapy. Results of these various treatment options with respect to local control, disease-free survival and overall survival will be considered for each of the various techniques with respect to size, grade, histologic type, surgical margin status, anatomic site, primary vs. recurrent disease. Similarly, the factors associated with delay in wound healing are to be considered and

Role of radiation therapy in management of patients with sarcoma of soft tissue

International Nuclear Information System (INIS)

Spiro, Ira J.; Suit, Herman D.

1997-01-01

Soft tissue sarcomas (STS) are relatively rare malignant neoplasms arising from the mesenchymal connective tissues. There are some 5600 newly diagnosed patients with STS per year. These tumors occur at all anatomic sites within the body and are of many histologic subtypes. Etiologic factors, including occupational risks, the role of environmental carcinogens, radiation and genetic diseases in the development of these tumors will be made. The molecular biology of soft tissue sarcomas including the role of several oncogenes and suppressor genes (e.g. Rb, p53, MDM2) will be reviewed. Cytogenetic alternations with an emphasis on molecular diagnostic techniques will be reviewed. The natural history of these tumors will be described with reference to local invasion and spread to regional and distal sites. The evaluation of the patients suspected of having a sarcoma of soft tissue will then be considered including the relative roles of various imaging modalities. The timing and type of biopsy (including FNA, core needle biopsy, incisional biopsy or excisional biopsy) for tumors at various sites and sizes will be addressed. Assessment of histopathologic subtype of the tumor by standard H and E stains, immunohistochemistry, electron microscopy and cytogenetic studies will then be discussed. The principal role for radiation in the management of patients with sarcoma of soft tissue is in combination with surgery. This may be: 1) pre-operative and or post-operative use of external beam photons, electrons, and protons, and 2) intra-operative use of electron beam techniques, or 3) post-operative brachytherapy. Results of these various treatment options with respect to local control, disease-free survival and overall survival will be considered for each of the various techniques with respect to size, grade, histologic type, surgical margin status, anatomic site, primary vs. recurrent disease. Similarly, the factors associated with delay in wound healing are to be considered and

Radiation therapy and late reactions in normal tissues

International Nuclear Information System (INIS)

Aoyama, Takashi; Kuroda, Yasumasa

1998-01-01

Recent developments in cancer therapy have made us increasingly aware that the quality of life of a patient is as valuable as other benefits received from therapy. This awareness leads to an emphasis on organ and/or function preservation in the course of therapy. In line with this new thinking, greater consideration is placed on radiation therapy as an appropriate modality of cancer therapy. Possible complications in normal tissues, especially those of late reaction type after the therapy must be overcome. This review, therefore, focuses on recent progress of studies on mechanisms of the complications of the late reaction type. An observation of a clinical case concerning a late reaction of spinal cord (radiation myelopathy) and surveys of experimental studies on the mechanisms of late reactions (including radiation pneumonitis and lung fibrosis, and radiation response of vascular endothelial cells) provide a hypothesis that apoptosis through the pathway starting with radiation-induced sphingomyelin hydrolysis may play an important role in causing a variety of late reactions. This insight is based on the fact that radiation also activates protein kinase C which appears to block apoptosis. The mechanisms of late reactions, therefore, may involve a balance between radiation-induced apoptotic death and its down regulation by suppressor mechanisms through protein kinase C. (author)

Association Between Pulmonary Uptake of Fluorodeoxyglucose Detected by Positron Emission Tomography Scanning After Radiation Therapy for Non-Small-Cell Lung Cancer and Radiation Pneumonitis

International Nuclear Information System (INIS)

Mac Manus, Michael P.; Ding Zhe; Hogg, Annette; Herschtal, Alan; Binns, David; Ball, David L.; Hicks, Rodney J.

2011-01-01

Purpose: To study the relationship between fluorodeoxyglucose (FDG) uptake in pulmonary tissue after radical radiation therapy (RT) and the presence and severity of radiation pneumonitis. Methods and Materials: In 88 consecutive patients, 18 F-FDG-positron emission tomography was performed at a median of 70 days after completion of RT. Patients received 60 Gy in 30 fractions, and all but 15 had concurrent platinum-based chemotherapy. RT-induced pulmonary inflammatory changes occurring within the radiation treatment volume were scored, using a visual (0 to 3) radiotoxicity grading scale, by an observer blinded to the presence or absence of clinical radiation pneumonitis. Radiation pneumonitis was retrospectively graded using the Radiation Therapy Oncology Group (RTOG) scale by an observer blinded to the PET radiotoxicity score. Results: There was a significant association between the worst RTOG pneumonitis grade occurring at any time after RT and the positron emission tomograph (PET) radiotoxicity grade (one-sided p = 0.033). The worst RTOG pneumonitis grade occurring after the PET scan was also associated with the PET radiotoxicity grade (one-sided p = 0.035). For every one-level increase in the PET toxicity scale, the risk of a higher RTOG radiation pneumonitis score increased by approximately 40%. The PET radiotoxicity score showed no significant correlation with the duration of radiation pneumonitis. Conclusions: The intensity of FDG uptake in pulmonary tissue after RT determined using a simple visual scoring system showed significant correlation with the presence and severity of radiation pneumonitis. 18 F-FDG-PET may be useful in the prediction, diagnosis and therapeutic monitoring of radiation pneumonitis.

Normal tissue tolerance to external beam radiation therapy: Peripheral nerves

International Nuclear Information System (INIS)

Henriques de Figueiredo, B.; Dejean, C.; Sargos, P.; Kantor, G.; Huchet, A.; Mamou, N.; Loiseau, H.

2010-01-01

Plexopathies and peripheral neuropathies appear progressively and with several years delay after radiotherapy. These lesions are observed principally after three clinical situations: supraclavicular and axillar irradiations for breast cancer, pelvic irradiations for various pathologies and limb irradiations for soft tissue sarcomas. Peripheral nerves and plexus (brachial and lumbosacral) are described as serial structures and are supposed to receive less than a given maximum dose linked to the occurrence of late injury. Literature data, mostly ancient, define the maximum tolerable dose to a threshold of 60 Gy and highlight also a great influence of fractionation and high fraction doses. For peripheral nerves, most frequent late effects are pain with significant differences of occurrence between 50 and 60 Gy. At last, associated pathologies (diabetes, vascular pathology, neuropathy) and associated treatments have probably to be taken into account as additional factors, which may increase the risk of these late radiation complications. (authors)

Substitution of the radiation requirement for sporulation by host tissue in Dendrophoma obscurans

International Nuclear Information System (INIS)

Binder, F.L.; Lilly, V.G.

1975-01-01

Cultures of Dendrophoma obscurans growing on a 10--2 glucose-casein hydrolysate medium required radiation for sporulation. When leaf discs from host tissue or certain plants, particularly members of the Rosaceae, were added to the basal medium, sporulation occurred abundantly in darkness on the leaf surface. The ability to replace the radiation requirement for sporulation did not occur with all plant tissue tested. The active substance in powdered host tissue could be extracted with certain organic solvents but not with water. This crude extract could be concentrated, autoclaved, and when added to the basal medium supported sporulation in darkness

Mobilization of Circulating Vascular Progenitors in Cancer Patients Receiving External Beam Radiation in Response to Tissue Injury

International Nuclear Information System (INIS)

Allan, David S.; Morgan, Scott C.; Birch, Paul E.; Yang, Lin; Halpenny, Michael J.; Gunanayagam, Angelo; Li Yuhua; Eapen, Libni

2009-01-01

Purpose: Endothelial-like vascular progenitor cells (VPCs) are associated with the repair of ischemic tissue injury in several clinical settings. Because the endothelium is a principal target of radiation injury, VPCs may be important in limiting toxicity associated with radiotherapy (RT) in patients with cancer. Methods and Materials: We studied 30 patients undergoing RT for skin cancer (n = 5), head-and-neck cancer (n = 15), and prostate cancer (n = 10) prospectively, representing a wide range of irradiated mucosal volumes. Vascular progenitor cell levels were enumerated from peripheral blood at baseline, midway through RT, at the end of treatment, and 4 weeks after radiation. Acute toxicity was graded at each time point by use of the National Cancer Institute's Common Toxicity Criteria, version 3.0. Results: Significant increases in the proportion of CD34 + /CD133 + VPCs were observed after completion of RT, from 0.012% at baseline to 0.048% (p = 0.029), and the increase in this subpopulation was most marked in patients with Grade 2 peak toxicity or greater after RT (p = 0.034). Similarly, CD34 + /vascular endothelial growth factor receptor 2-positive VPCs were increased after the completion of radiation therapy in comparison to baseline (from 0.014% to 0.027%, p = 0.043), and there was a trend toward greater mobilization in patients with more significant toxicity (p = 0.08). The mobilization of CD34 + hematopoietic stem cells did not increase after treatment (p = 0.58), and there was no relationship with toxicity. Conclusions: We suggest that VPCs may play an important role in reducing radiation-induced tissue damage. Interventions that increase baseline VPC levels or enhance their mobilization and recruitment in response to RT may prove useful in facilitating more rapid and complete tissue healing.

Stem cell therapy for the treatment of radiation-induced normal tissue damage

International Nuclear Information System (INIS)

Chapel, A.; Benderitter, M.; Gourmelon, P.; Lataillade, J.J.; Gorin, N.C.

2013-01-01

Radiotherapy may induce irreversible damage on healthy tissues surrounding the tumour. In Europe, per year, 1.5 million patients undergo external radiotherapy. Acute adverse effect concern 80% of patients. The late adverse effect of radiotherapy concern 5 to 10% of them, which could be life threatening. Eradication of these manifestations is crucial. The French Institute of Radioprotection and Nuclear Safety (IRSN) contribute to understand effect of radiation on healthy tissue. IRSN is strongly implicated in the field of regeneration of healthy tissue after radiotherapy or radiological accident and in the clinical use of cell therapy in the treatment of irradiated patients. Our first success in cell therapy was the correction of deficient hematopoiesis in two patients. The intravenous injection of Mesenchymal Stem Cells (MSC) has restored bone marrow micro-environment after total body irradiation necessary to sustain hematopoiesis. Cutaneous radiation reactions play an important role in radiation accidents, but also as a limitation in radiotherapy and radio-oncology. We have evidenced for the first time, the efficiency of MSC therapy in the context of acute cutaneous and muscle damage following irradiation in five patients. Concerning the medical management of gastrointestinal disorder after irradiation, we have demonstrated the promising approach of the MSC treatment. We have shown that MSC migrate to damaged tissues and restore gut functions after radiation damage. The evaluation of stem cell therapy combining different sources of adult stem cells is under investigation

On radiation damage to normal tissues and its treatment. Pt. 2

International Nuclear Information System (INIS)

Michalowski, A.S.

1994-01-01

In addition to transiently inhibiting cell cycle progression and sterilizing those cells capable of proliferation, irradiation disturbs the homeostasis effected by endogenous mediators of intercellular communication (humoral component of tissue response to radiation). Changes in the mediator levels may modulate radiation effects either by a assisting a return to normality (e.g., through a rise in H-type cell lineage-specific growth factors) or by aggravating the damage. The latter mode is illustrated with reports on changes in eicosanoid levels after irradiation and on results of empirical treatment of radiation injuries with anti-inflammatory drugs. Prodromal, acute and chronic effects of radiation are accompanied by excessive production of eicosanoids (prostaglandins, prostacyclin, thromboxanes and leukotrienes). These endogenous mediators of inflammatory reactions may be responsible for the vasodilatation, vasoconstriction, increased microvascular permeability, thrombosis and chemotaxis observed after radiation exposure. Glucocorticoids inhibit eicosanoid synthesis primarily by interfering with phospholipase A 2 whilst non-steroidal anti-inflammatory drugs prevent prostaglandin/thromboxane synthesis by inhibiting cycloxygenase. When administered after irradiation on empirical grounds, drugs belonging to both groups tend to attenuate a range of prodomal, acute and chronic effects of radiation in man and animals. Taken together, these two sets of observations are highly suggestive of a contribution of humoral factors to the adverse responses of normal tissues and organs to radiation. A full account of radiation damage should therefore consist of complementary descriptions of cellular and humoral events. Further studies on anti-inflammatory drug treatment of radiation damage to normal organs are justified and desirable. (orig.)

Genetic differences in transcript responses to low-dose ionizing radiation identify tissue functions associated with breast cancer susceptibility.

Science.gov (United States)

Snijders, Antoine M; Marchetti, Francesco; Bhatnagar, Sandhya; Duru, Nadire; Han, Ju; Hu, Zhi; Mao, Jian-Hua; Gray, Joe W; Wyrobek, Andrew J

2012-01-01

High dose ionizing radiation (IR) is a well-known risk factor for breast cancer but the health effects after low-dose (LD, differences in their sensitivity to radiation-induced mammary cancer (BALB/c and C57BL/6) for the purpose of identifying mechanisms of mammary cancer susceptibility. Unirradiated mammary and blood tissues of these strains differed significantly in baseline expressions of DNA repair, tumor suppressor, and stress response genes. LD exposures of 7.5 cGy (weekly for 4 weeks) did not induce detectable genomic instability in either strain. However, the mammary glands of the sensitive strain but not the resistant strain showed early transcriptional responses involving: (a) diminished immune response, (b) increased cellular stress, (c) altered TGFβ-signaling, and (d) inappropriate expression of developmental genes. One month after LD exposure, the two strains showed opposing responses in transcriptional signatures linked to proliferation, senescence, and microenvironment functions. We also discovered a pre-exposure expression signature in both blood and mammary tissues that is predictive for poor survival among human cancer patients (p = 0.0001), and a post-LD-exposure signature also predictive for poor patient survival (pidentify genetic features that predispose or protect individuals from LD-induced breast cancer.

Sensitivity/uncertainty analysis for free-in-air tissue kerma due to initial radiation at Hiroshima and Nagasaki

International Nuclear Information System (INIS)

Lillie, R.A.; Broadhead, B.L.; Pace, J.V. III

1988-01-01

Uncertainty estimates and cross correlations by range/survivor have been calculated for the Hiroshima and Nagasaki free-in-air (FIA) tissue kerma obtained from two-dimensional air/ground transport calculations. The uncertainties due to modeling parameter and basic nuclear transport data uncertainties were calculated for 700-, 1000-, and 1500-m ground ranges. Only the FIA tissue kerma due to initial radiation was treated in the analysis; the uncertainties associated with terrain and building shielding and phantom attenuation were not considered in this study. Uncertainties of --20% were obtained for the prompt neutron and secondary gamma kerma and 30% for the prompt gamma kerma at both cities. The uncertainties on the total prompt kerma at Hiroshima and Nagasaki are --18 and 15%, respectively. The estimated uncertainties vary only slightly by ground range and are fairly highly correlated. The total prompt kerma uncertainties are dominated by the secondary gamma uncertainties, which in turn are dominated by the modeling parameter uncertainties, particularly those associated with the weapon yield and radiation sources

Statistical Modeling of Radiative Transfer and Transient Characteristics for Multilayer Biological Tissue

Directory of Open Access Journals (Sweden)

S. Yu. Makarov

2014-01-01

Full Text Available The Monte-Carlo method [1] already long ago proved itself as a powerful and universal tool for mathematical modelling in various areas of science and engineering. Researchers often choose this method when it is difficult to find a solution by other ways (or impossible at all, e.g. because of sophisticated analytical dependences, area of modelling or boundary conditions. Certainly, this necessarily statistical and flexible method requires significant computation time, but a continuously increasing computation capability makes it more and more attractive for a choice in specific situation.One of the promising areas to use the method of statistical modelling is description of light propagation in the turbid (scattering media. A high motivation for development of this approach is widely used lasers in biomedicine [3]. Besides, owing to its flexibility, the Monte-Carlo method is also of importance in theoretical researches, in particular, to estimate a degree of adequacy of the offered approximation methods for solving a radiative transfer equation [4].It is known that key parameters of turbid media are an absorption coefficient (characterizes absorption probability of a photon per unit of path length and a scattering coefficient (characterizes scattering probability of a photon per unit of path length. The ratio of each of the coefficients to their sum (extinction defines a probability of "death" or "survival" of a photon, respectively, in interaction with lenses. Generally, in the scattering medium there is a non-coherent radiation component, which in turbid media such as biological tissues, already at the insignificant depth becomes prevailing over the coherent one (residual of the incident laser beam [5].The author used the Monte-Carlo method to simulate optical radiation propagation in the multilayer biological tissues with their optical characteristics corresponding to the skin and subcutaneous tissues. Such a biological tissue is the absorbing

Cardiovascular risks associated with low dose ionizing particle radiation.

Directory of Open Access Journals (Sweden)

Xinhua Yan

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

Early brain response to low-dose radiation exposure involves molecular networks and pathways associated with cognitive functions, advanced aging and Alzheimer's disease.

Science.gov (United States)

Lowe, Xiu R; Bhattacharya, Sanchita; Marchetti, Francesco; Wyrobek, Andrew J

2009-01-01

Understanding the cognitive and behavioral consequences of brain exposures to low-dose ionizing radiation has broad relevance for health risks from medical radiation diagnostic procedures, radiotherapy and environmental nuclear contamination as well as for Earth-orbit and space missions. Analyses of transcriptome profiles of mouse brain tissue after whole-body irradiation showed that low-dose exposures (10 cGy) induced genes not affected by high-dose radiation (2 Gy) and that low-dose genes were associated with unique pathways and functions. The low-dose response had two major components: pathways that are consistently seen across tissues and pathways that were specific for brain tissue. Low-dose genes clustered into a saturated network (P < 10(-53)) containing mostly down-regulated genes involving ion channels, long-term potentiation and depression, vascular damage, etc. We identified nine neural signaling pathways that showed a high degree of concordance in their transcriptional response in mouse brain tissue after low-dose irradiation, in the aging human brain (unirradiated), and in brain tissue from patients with Alzheimer's disease. Mice exposed to high-dose radiation did not show these effects and associations. Our findings indicate that the molecular response of the mouse brain within a few hours after low-dose irradiation involves the down-regulation of neural pathways associated with cognitive dysfunctions that are also down-regulated in normal human aging and Alzheimer's disease.

In vitro neoplastic transformation of plant callus tissue by γ-radiation

International Nuclear Information System (INIS)

Pandey, K.N.; Sabharwal, P.S.

1979-01-01

Tumours have been induced by γ-radiation in callus tissue derived from a monocotyledonous flowering plant, Haworthia mirabilis Haw. The transformed tissue exhibited compact texture, excessive cell proliferation and loss of capacity for organogenesis. Tumors were characterized by their ability to undergo continuous autonomous growth on minimal media in the subsequent 4 generations of subculture. In contrast, the nonirradiated control tissue grew with friable texture, required inositol or growth hormones and showed prolific differentiation of vegetative buds. (Auth.)

Early Brain Response to Low-Dose Radiation Exposure Involves Molecular Networks and Pathways Associated with Cognitive Functions, Advanced Aging and Alzheimer's Disease

Energy Technology Data Exchange (ETDEWEB)

Lowe, Xiu R; Bhattacharya, Sanchita; Marchetti, Francesco; Wyrobek, Andrew J.

2008-06-06

Understanding the cognitive and behavioral consequences of brain exposures to low-dose ionizing radiation has broad relevance for health risks from medical radiation diagnostic procedures, radiotherapy, environmental nuclear contamination, as well as earth orbit and space missions. Analyses of transcriptome profiles of murine brain tissue after whole-body radiation showed that low-dose exposures (10 cGy) induced genes not affected by high dose (2 Gy), and low-dose genes were associated with unique pathways and functions. The low-dose response had two major components: pathways that are consistently seen across tissues, and pathways that were brain tissue specific. Low-dose genes clustered into a saturated network (p < 10{sup -53}) containing mostly down-regulated genes involving ion channels, long-term potentiation and depression, vascular damage, etc. We identified 9 neural signaling pathways that showed a high degree of concordance in their transcriptional response in mouse brain tissue after low-dose radiation, in the aging human brain (unirradiated), and in brain tissue from patients with Alzheimer's disease. Mice exposed to high-dose radiation did not show these effects and associations. Our findings indicate that the molecular response of the mouse brain within a few hours after low-dose irradiation involves the down-regulation of neural pathways associated with cognitive dysfunctions that are also down regulated in normal human aging and Alzheimer's disease.

Variability of individual normal tissue radiation sensitivity. An international empirical evaluation of endogenous and exogenous

International Nuclear Information System (INIS)

Zimmermann, J.S.; Kumpf, L.; Kimmig, B.

1998-01-01

Background: The variability of normal-tissue response is of major concern for radiation therapy. Multiple endogenous and exogenous factors are qualitatively known to alter the acute and late tissue response. Which of them are regarded most important by the European radiation oncologists and what is, empirically, their quantitative influence on the acute or late tissue tolerance? Methods: In August 1997, we sent a questionnaire to 255 European radiation oncology departments. Among others, the questionnaire asked for endogenous and exogenous factors modifying the tissue response to radiation therapy and their quantitative influence on the acute and late radiation morbidity (TD5/5). Fifty-five questionnaires (21.5%) were answered. Results: Empirically, the most important endogenous factors to modify the acute tissue tolerance are (a) metabolic/other diseases with macro- or microangiopathia (17 answers [a]/32% mean decrease of tissue tolerance), (b) collagen diseases (9 a/37%) and (c) immune diseases (5 a/53%). As endogenous response modifiers for the TD5/5 are recognized (a) metabolic or other diseases leading to marcro- or microangiopathia (15 a/31%), (b) collagen diseases (11 a/38%) and (c) immune diseases (2 a/50%). Inflammations from any reason are assumed to alter the acute tissue tolerance by (6 a/26%) and the TD5/5 by (10 a/24%). Exogenous modifiers of the acute tissue response mentioned are (a) smoking (34 a/44%), (b) alcohol (23 a/45%), (c) nutrition/diets (16 a/45%), (d) hygiene (9 a/26%) and (e) medical therapies (10 a/37%). Exogenous factors assumed to influence the TD5/5 are (a) smoking (22 a/40%), (b) alcohol (15 a/38%), (c) nutrition/diets (9 a/48%), (d) hygiene (5 a/34%) and (e) medical therapies (10 a/30%). Conclusions: Exogenous factors are regarded more important by number and extent on the acute and late tissue response than endogenous modifiers. Both may have an important influence on the individual expression of normal tissue response. (orig

Modification of transmission dose algorithm for irregularly shaped radiation field and tissue deficit

Energy Technology Data Exchange (ETDEWEB)

Yun, Hyong Geon; Shin, Kyo Chul [Dankook Univ., College of Medicine, Seoul (Korea, Republic of); Huh, Soon Nyung; Woo, Hong Gyun; Ha, Sung Whan [Seoul National Univ., College of Medicine, Seoul (Korea, Republic of); Lee, Hyoung Koo [The Catholic Univ., College of Medicine, Seoul (Korea, Republic of)

2002-07-01

Algorithm for estimation of transmission dose was modified for use in partially blocked radiation fields and in cases with tissue deficit. The beam data was measured with flat solid phantom in various conditions of beam block. And an algorithm for correction of transmission dose in cases of partially blocked radiation field was developed from the measured data. The algorithm was tested in some clinical settings with irregular shaped field. Also, another algorithm for correction of transmission dose for tissue deficit was developed by physical reasoning. This algorithm was tested in experimental settings with irregular contours mimicking breast cancer patients by using multiple sheets of solid phantoms. The algorithm for correction of beam block could accurately reflect the effect of beam block, with error within {+-}1.0%, both with square fields and irregularly shaped fields. The correction algorithm for tissue deficit could accurately reflect the effect of tissue deficit with errors within {+-}1.0% in most situations and within {+-}3.0% in experimental settings with irregular contours mimicking breast cancer treatment set-up. Developed algorithms could accurately estimate the transmission dose in most radiation treatment settings including irregularly shaped field and irregularly shaped body contour with tissue deficit in transmission dosimetry.

Modification of transmission dose algorithm for irregularly shaped radiation field and tissue deficit

International Nuclear Information System (INIS)

Yun, Hyong Geon; Shin, Kyo Chul; Huh, Soon Nyung; Woo, Hong Gyun; Ha, Sung Whan; Lee, Hyoung Koo

2002-01-01

Algorithm for estimation of transmission dose was modified for use in partially blocked radiation fields and in cases with tissue deficit. The beam data was measured with flat solid phantom in various conditions of beam block. And an algorithm for correction of transmission dose in cases of partially blocked radiation field was developed from the measured data. The algorithm was tested in some clinical settings with irregular shaped field. Also, another algorithm for correction of transmission dose for tissue deficit was developed by physical reasoning. This algorithm was tested in experimental settings with irregular contours mimicking breast cancer patients by using multiple sheets of solid phantoms. The algorithm for correction of beam block could accurately reflect the effect of beam block, with error within ±1.0%, both with square fields and irregularly shaped fields. The correction algorithm for tissue deficit could accurately reflect the effect of tissue deficit with errors within ±1.0% in most situations and within ±3.0% in experimental settings with irregular contours mimicking breast cancer treatment set-up. Developed algorithms could accurately estimate the transmission dose in most radiation treatment settings including irregularly shaped field and irregularly shaped body contour with tissue deficit in transmission dosimetry

Applicability of the tissue stem cell turnover concept on the validity of cumulative dose based radiation risk evaluation

International Nuclear Information System (INIS)

Otsuka, Kensuke; Hamada, Nobuyuki; Iwasaki, Toshiyasu; Yoshida, Kazuo

2011-01-01

The radiation protection system adopts the linear no-threshold model to achieve proper radiation protection for considering cancer risks resulting from radiation exposure. This model uses cumulative dose to a tissue for risk evaluation in which cumulative dose is related to the amount of DNA damage and consequential induction of gene mutation. In this concept, gene mutation accumulates in tissue stem cells, the putative target of carcinogenesis, with total dose given to the tissue. Unlike high-dose-rate exposure, epidemiological studies in high radiation background areas, such as Kerala in India, revealed that cancer risks is not elevated by the dose to the inhabitants, suggesting that there exists some mechanisms to eliminate the damage/mutation in the exposed tissue under extremely low-dose-rate exposure situations. In this report, the dynamics of tissue stem cell turnover is evaluated as a possible mechanism under extremely low-dose-rate exposure situations. To this end, we reviewed recent literatures studying tissue stem cell turnover, and found that great advances in stem cell research have made it possible to trace a fate of stem cells in tissues. Furthermore, turnover of tissue stem cells is found to occur after irradiation, due to competition of stem cells within tissues. This raises a possibility that radiation effects may not accumulate in a tissue depending on the dose-rate and duration of exposure period. (author)

Post-radiation changes in oral tissues - An analysis of cancer irradiation cases

Directory of Open Access Journals (Sweden)

Jay Ashokkumar Pandya

2014-01-01

Full Text Available Introduction: Radiation, commonly employed as neoadjuvant, primary, and adjuvant therapy for head and neck cancer causes numerous epithelial and stromal changes, prominent among which is fibrosis with its early and late consequences. Very little is known about the true nature of the fibrosed tissue and the type of fibers accumulated. Radiotherapy affects the supporting tumor stroma often resulting in a worsening grade of tumor post-radiation. Aim: To study epithelial, neoplastic, stromal, and glandular changes in oral cavity induced by radiation therapy for oral squamous cell carcinoma (OSCC using special stains. Materials and Methods: The study included 27 samples of recurrent OSCC following completion of radiotherapy (recurrence within an average span of 11 months, and 26 non-irradiated cases of OSCC. Patients with a history of combined radiotherapy and chemotherapy were not included in the study. The epithelial changes assessed included epithelial atrophy, apoptosis, necrosis, dysplasia, and neoplasia. The connective tissue was evaluated for amount of fibrosis, quality of fibers (using picrosirius red staining, fibrinous exudate, necrosis, pattern of invasion, vessel wall thickening, and salivary gland changes. The aforementioned changes were assessed using light and polarizing microscopy and tabulated. Statistical Analysis: Epithelial and connective tissue parameters were compared between the irradiated and non-irradiated cases using chi square and t-tests. Results: Epithelial and connective tissue parameters were found to be increased in irradiated patients. Pattern of invasion by tumor cells varied from strands and  cords between the two groups studied. The effect of radiation was seen to reflect on the maturity of fibers and the regularity of their distribution.

Effect of ionizing radiation on tissue proteins of the desert locust, Schistocerca gregaria Forskal

International Nuclear Information System (INIS)

Rao, P.J.; Singh, Y.; Mehrotra, K.N.

1981-01-01

Effect of gamma radiation on the protein concentration of thoracic and mandibular muscles and midgut of adult male desert locust, Schistocerca gregaria Forskal at 2.5, 5.0 and 7.5 Krad doses was studied. The protein concentration of thoracic muscles was the highest on a μg/mg wet tissue basis, followed by the mandibular muscles and midgut. Considerable increase in protein concentration of the tissues on 5th and 9th day and depletion on 7th day suggests the existence of a circadian rhythm like phenomenon in tissue proteins. The effect of radiation on protein concentration of thoracic and mandibular muscles was comparatively more pronounced than midgut tissue and was generally dose dependent. (author)

UV-B Radiation Impacts Shoot Tissue Pigment Composition in Allium fistulosum L. Cultigens

Directory of Open Access Journals (Sweden)

Kristin R. Abney

2013-01-01

Full Text Available Plants from the Allium genus are valued worldwide for culinary flavor and medicinal attributes. In this study, 16 cultigens of bunching onion (Allium fistulosum L. were grown in a glasshouse under filtered UV radiation (control or supplemental UV-B radiation [7.0 μmol·m−2·s−2 (2.68 W·m−2] to determine impacts on growth, physiological parameters, and nutritional quality. Supplemental UV-B radiation influenced shoot tissue carotenoid concentrations in some, but not all, of the bunching onions. Xanthophyll carotenoid pigments lutein and β-carotene and chlorophylls a and b in shoot tissues differed between UV-B radiation treatments and among cultigens. Cultigen “Pesoenyj” responded to supplemental UV-B radiation with increases in the ratio of zeaxanthin + antheraxanthin to zeaxanthin + antheraxanthin + violaxanthin, which may indicate a flux in the xanthophyll carotenoids towards deepoxydation, commonly found under high irradiance stress. Increases in carotenoid concentrations would be expected to increase crop nutritional values.

Normal tissue tolerance to external beam radiation therapy: Adult bone

International Nuclear Information System (INIS)

Sargos, P.; Mamou, N.; Dejean, C.; Henriques de Figueiredo, B.; Kantor, G.; Huchet, A.; Italiano, A.

2010-01-01

Radiation tolerance for bone tissue has been mostly evaluated with regard to bone fracture. Main circumstances are mandibula osteoradionecrosis, hip and costal fracture, and patent or radiologic fractures in the treated volume. After radiation therapy of bone metastasis, the analysis of related radiation fracture is difficult to individualize from a pathologic fracture. Frequency of clinical fracture is less than 5% in the large series or cohorts and is probably under-evaluated for the asymptomatic lesions. Women older than 50 years and with osteoporosis are probably the main population at risk. Dose-effect relations are difficult to qualify in older series. Recent models evaluating radiations toxicity on diaphysa suggest an important risk after 60 Gy, for high dose-fraction and for a large volume. (authors)

Professor Glyn O. Phillip's legacy within the IAEA programme on radiation and tissue banking.

Science.gov (United States)

Morales Pedraza, Jorge

2017-08-19

Professor Phillips began his involvement in the implementation of this important IAEA programme, insisting that there were advantages to be gained by using the ionizing radiation technique to sterilize human and animal tissues, based on the IAEA experience gained in the sterilization of medical products. The outcome of the implementation of the IAEA programme on radiation and tissue banking demonstrated that Professor Phillips was right in his opinion.

[Forensic medical implications of histomorphological changes in the bone and cartilage tissues under effect of radiation].

Science.gov (United States)

Osipenkova-Vichtomova, T K

2013-01-01

The objective of the present work was to study roentgenological, microscopic, and histomorphological changes in the bone and cartilage tissues under effect of different doses of gamma-ray radiation from Gammatron-2 (GUT Co 400) and betatron bremsstrahlung radiation (25 MeV). The total radiation dose varied from 9.6 Gy to 120 Gy per unit area during 5-8 weeks. The study included 210 patients at the age from 7 to 82 years (97 men and 113 women). Histomorphological studies were carried out using samples of bone and cartilage tissues taken from different body regions immediately after irradiation and throughout the follow-up period of up to 4 years 6 months. Control samples were the unexposed bone and cartilage tissues from the same subjects (n = 14). The tissues were stained either with eosin and hematoxylin or by Van Gieson's and Mallory's methods. Gomori's nonspecific staining was used to detect acid and alkaline phosphatase activities. Moreover, argyrophilic substance was identified in the cartilaginous tissue. Best's carmine was used for glycogen staining and Weigert's stain for elastic fibers. Metachromasia was revealed by toluidine blue staining and fat by the sudan III staining technique. In addition, the ultrastructure of cartilaginous tissue was investigated. Taken together, these methods made it possible to identify the signs of radiation-induced damage to the bone and cartilage tissues in conjunction with complications that are likely to develop at different periods after irradiation including such ones as spontaneous fractures, deforming arthrosis and radiation-induced tumours.

Dielectric losses in tissues under ionizing radiation conditions

International Nuclear Information System (INIS)

Kamalov, N.; Narizov, N.N.; Norbaev, N.

1977-01-01

Dielectric losses of tissues caused by ionizing radiation were studied. The experiments were carried out on seven-day-old seedlings of two wild cotton species (G. barbadense ssp. darvini, G. hirsutum ssp. mexicanum) and of cultivated cotton sorts Tashkent-1, C-6030, AN-401. The study showed that the irradiation of the seedlings with CO 60 gamma-rays (radiation doses 0.3, 3, 20, 35 kr, the dose rate 90 rs/s) changed the tangent of the angle of losses. It was found out that the maximum tangent of the angle of dielectric losses tg sigma of cultivated forms lies within the range of 5-10 kHz frequencies, this value changing under the effect of radiation to a greater extent in wild-growing ssp. mexicanum cotton plants than in commercial varieties (Tashkent 1). In commercial cotton varieties, in distinction to wild forms, the radiation is shifting tg sigma to low frequencies. The electric capacity is much lower in wild forms (ssp. mexicanum) than in cultivated cotton seedlings. Thus the capacity of cells and the maximum of the tg sigma absorption in cultivated and wild cotton seedlings are significantly different which is probably connected with their different radiosensitivity to the ionizing radiation

Tissue Respiration and Glycolysis in the Development of Acute Radiation Sickness

National Research Council Canada - National Science Library

Golubentsev, D

1960-01-01

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

Localized Ocular Adnexal Mucosa-Associated Lymphoid Tissue Lymphoma Treated With Radiation Therapy: A Long-Term Outcome in 86 Patients With 104 Treated Eyes

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Harada, Ken, E-mail: keharada@ncc.go.jp [Department of Radiation Oncology, National Cancer Center Hospital, Tokyo (Japan); Murakami, Naoya; Kitaguchi, Mayuka; Sekii, Shuhei; Takahashi, Kana; Yoshio, Kotaro; Inaba, Koji; Morota, Madoka; Ito, Yoshinori; Sumi, Minako [Department of Radiation Oncology, National Cancer Center Hospital, Tokyo (Japan); Suzuki, Shigenobu [Department of Ophthalmic Oncology, National Cancer Center Hospital, Tokyo (Japan); Tobinai, Kensei [Department of Hematologic Oncology, National Cancer Center Hospital, Tokyo (Japan); Uno, Takashi [Department of Radiology, Chiba University School of Medicine, Chiba (Japan); Itami, Jun [Department of Radiation Oncology, National Cancer Center Hospital, Tokyo (Japan)

2014-03-01

Purpose: To evaluate the natural history, behavior of progression, prognostic factors, and treatment-related adverse effects of primary ocular adnexal mucosa-associated lymphoid tissue (MALT) lymphoma (POAML). Methods and Materials: Eighty-six patients with histologically proven stage I POAML treated with radiation therapy at National Cancer Center Hospital, Tokyo between 1990 and 2010 were retrospectively reviewed. The median age was 56 years (range, 18-85 years). The median dose administered was 30 Gy (range, 30-46 Gy). Seventy-seven patients (90%) were treated by radiation therapy alone. Results: The median follow-up duration was 9 years (range, 0.9-22 years). The 5- and 10-year overall survival (OS) rates were 97.6% and 93.5%, respectively, and no patients died of lymphoma. Patients with tumor sizes ≥4 cm showed a greater risk of contralateral relapse (P=.012). Six patients with contralateral relapse were seen and treated by radiation therapy alone, and all the lesions were controlled well, with follow-up times of 3 to 12 years. There was 1 case of local relapse after radiation therapy alone, and 3 cases of relapse occurred in a distant site. Cataracts developed in 36 of the 65 eyes treated without lens shielding and in 12 of the 39 patients with lens shielding (P=.037). Conclusions: The majority of patients with POAML showed behavior consistent with that of localized, indolent diseases. Thirty gray of local irradiation seems to be quite effective. The initial bilateral involvement and contralateral orbital relapses can be also controlled with radiation therapy alone. Lens shielding reduces the risk of cataract.

Localized Ocular Adnexal Mucosa-Associated Lymphoid Tissue Lymphoma Treated With Radiation Therapy: A Long-Term Outcome in 86 Patients With 104 Treated Eyes

International Nuclear Information System (INIS)

Harada, Ken; Murakami, Naoya; Kitaguchi, Mayuka; Sekii, Shuhei; Takahashi, Kana; Yoshio, Kotaro; Inaba, Koji; Morota, Madoka; Ito, Yoshinori; Sumi, Minako; Suzuki, Shigenobu; Tobinai, Kensei; Uno, Takashi; Itami, Jun

2014-01-01

Purpose: To evaluate the natural history, behavior of progression, prognostic factors, and treatment-related adverse effects of primary ocular adnexal mucosa-associated lymphoid tissue (MALT) lymphoma (POAML). Methods and Materials: Eighty-six patients with histologically proven stage I POAML treated with radiation therapy at National Cancer Center Hospital, Tokyo between 1990 and 2010 were retrospectively reviewed. The median age was 56 years (range, 18-85 years). The median dose administered was 30 Gy (range, 30-46 Gy). Seventy-seven patients (90%) were treated by radiation therapy alone. Results: The median follow-up duration was 9 years (range, 0.9-22 years). The 5- and 10-year overall survival (OS) rates were 97.6% and 93.5%, respectively, and no patients died of lymphoma. Patients with tumor sizes ≥4 cm showed a greater risk of contralateral relapse (P=.012). Six patients with contralateral relapse were seen and treated by radiation therapy alone, and all the lesions were controlled well, with follow-up times of 3 to 12 years. There was 1 case of local relapse after radiation therapy alone, and 3 cases of relapse occurred in a distant site. Cataracts developed in 36 of the 65 eyes treated without lens shielding and in 12 of the 39 patients with lens shielding (P=.037). Conclusions: The majority of patients with POAML showed behavior consistent with that of localized, indolent diseases. Thirty gray of local irradiation seems to be quite effective. The initial bilateral involvement and contralateral orbital relapses can be also controlled with radiation therapy alone. Lens shielding reduces the risk of cataract

Treatment of Vascular Soft Tissue Sarcomas With Razoxane, Vindesine, and Radiation

International Nuclear Information System (INIS)

Rhomberg, Walter; Wink, Anna; Pokrajac, Boris; Eiter, Helmut; Hackl, Arnulf; Pakisch, Brigitte; Ginestet, Angela; Lukas, Peter; Poetter, Richard Prof.

2009-01-01

Purpose: In previous studies, razoxane and vindesine together with radiotherapy was proved to be effective in soft tissue sarcomas (STS). Because razoxane leads to a redifferentiation of pathological tumor blood vessels, it was of particular interest to study the influence of this drug combination in vascular soft tissue sarcomas. Methods and Materials: This open multicenter Phase II study was performed by the Austrian Society of Radiooncology. Among 13 evaluable patients (10 angiosarcomas and 3 hemangio-pericytomas), 9 had unresectable measurable disease, 3 showed microscopic residuals, and 1 had a resection with clear margins. They received a basic treatment with razoxane and vindesine supported by radiation therapy. Outcome measures were objective response rates, survival time, and the incidence of distant metastases. Results: In nine patients with measurable vascular soft tissue sarcomas (eight angiosarcomas and one hemangiopericytoma), 6 complete remissions, 2 partial remissions, and 1 minor remission were achieved, corresponding to a major response rate of 89%. A maintenance therapy with razoxane and vindesine of 1 year or longer led to a suppression of distant metastases. The median survival time from the start of the treatment is 23+ months (range, 3-120+) for 12 patients with macroscopic and microscopic residual disease. The progression-free survival at 6 months was 75%. The combined treatment was associated with a low general toxicity, but attention must be given to increased normal tissue reactions. Conclusions: This trimodal treatment leads to excellent response rates, and it suppresses distant metastases when given as maintenance therapy.

Effect of laminaria japonica polysaccharides (LJP) on radiation damage of testis tissue in male rats

International Nuclear Information System (INIS)

Ren Shicheng; Luo Qiong; Yang Mingliang; Yang Jiajuan; Yan Jun; Li Zhuoneng; Wang Lihong; Cui Xiaoyan

2007-01-01

Objective: To observe the effect of laminaria japonica polysaccharides (LJP) on local radiation damage of testis tissue in male rats. Methods: The Wistar rats were randomly divided into 4 groups: the normal group, the model group, positive control group and LJP treatment group (50 mg·kg -1 ·d -1 ). LJP was applied to the treatment group for 10 d before local irradiation with γ-ray (6.0 Gy). The morphological change of the testis, organ index of testis and epididymides, sperm count, motility rate, superoxide dismutase (SOD) activity and malonic aldehyde (MDA) contents were measured. Results: LJP could make the damaged testis recover to near normal, elevate the organ index of testis and epididymides, promote the sperm count and motility rate, increase the activity of SOD and decrease the contents of MDA in testis tissue. Conclusions: LJP could inhibit testis tissue damage induced by local radiation, hence enhance the significant radioprotective effect to testis tissue. LJP has the conspicuous protective effect on radiation damage of testis tissue. (authors)

ROLE OF TAURINE ON THE LEVEL OF SOME ESSENTIAL ELEMENTS AND OXIDATIVE STRESS IN DIFFERENT TISSUES OF RATS EXPOSED TO GAMMA RADIATION

International Nuclear Information System (INIS)

ANIS, L.M.

2008-01-01

Whole body exposure to ionizing radiation induces the formation of reactive oxygen species (ROS) in the different tissues provoking oxidative damage and organ dysfunction. The present study was designed to determine the possible protective effect of taurine against gamma radiation-induced disorders in iron (Fe), copper (Cu), zinc (Zn) and magnesium (Mg) in parallel to radiation-induced oxidative stress in liver, spleen and heart tissues. Irradiated rats were whole body exposed to 6.5 Gy gamma radiations. Taurine treated irradiated rats received 250 mg taurine/kg body weight/day for 10 successive days before irradiation. Animals were sacrificed on 1 st , 7 th and 14 th days after irradiation. The results obtained demonstrated significant increases in Fe, Cu, Zn and Mg levels in the liver. Significant increases of Fe and Cu and significant decrease of Zn and non-significant changes in Mg were observed in the spleen. Heart tissues showed significant decrease in the level of iron and non-significant changes in the levels of Cu, Zn and Mg. Alterations in the levels of essential elements were associated with oxidative stress. Significant decreases of SOD and CAT activities along with significant increase of TBARS levels were recorded in the different tissues after irradiation. Taurine administration pre-irradiation has significantly attenuated the radiation-induced oxidative stress and alteration in the levels of essential elements. It could be concluded that taurine might protect from oxidative damage induced by gamma irradiation

Epidermal Homeostasis and Radiation Responses in a Multiscale Tissue Modeling Framework

Science.gov (United States)

Hu, Shaowen; Cucinotta, Francis A.

2013-01-01

The surface of skin is lined with several thin layers of epithelial cells that are maintained throughout life time by a small population of stem cells. High dose radiation exposures could injure and deplete the underlying proliferative cells and induce cutaneous radiation syndrome. In this work we propose a multiscale computational model for skin epidermal dynamics that links phenomena occurring at the subcellular, cellular, and tissue levels of organization, to simulate the experimental data of the radiation response of swine epidermis, which is closely similar to human epidermis. Incorporating experimentally measured histological and cell kinetic parameters, we obtain results of population kinetics and proliferation indexes comparable to observations in unirradiated and acutely irradiated swine experiments. At the sub-cellular level, several recently published Wnt signaling controlled cell-cycle models are applied and the roles of key components and parameters are analyzed. Based on our simulation results, we demonstrate that a moderate increase of proliferation rate for the survival proliferative cells is sufficient to fully repopulate the area denuded by high dose radiation, as long as the integrity of underlying basement membrane is maintained. Our work highlights the importance of considering proliferation kinetics as well as the spatial organization of tissues when conducting in vivo investigations of radiation responses. This integrated model allow us to test the validity of several basic biological rules at the cellular level and sub-cellular mechanisms by qualitatively comparing simulation results with published research, and enhance our understanding of the pathophysiological effects of ionizing radiation on skin.

Modulation of radiation effects in tissues by keratinocyte growth factor (KGF)

International Nuclear Information System (INIS)

Doerr, W.; Lacmann, A.; Noack, R.; Spekl, K.

2000-01-01

Keratinocyte Growth Factor (KGF) is a member of the fibroblast growth factor family. KGF is produced by mesenchymal cells, predominantly fibroblasts; target cells are epithelial cells in a variety of tissues. Hence, KGF is a mediator of the mesenchymal-epithelial communication and a regulator of tissue homeostasis in epithelia. Systemic administration of KGF in animal models induces stimulation of proliferation and modulation of migration and differentiation processes in squamous epithelia. This results in a transient increase in cell numbers and epithelial thickness. Radiation exposure of epithelia causes an imbalance between cell production and cell loss, which in consequence causes progressive cell depletion and eventually complete denudation. Systemic application of KGF reduces the radiation-induced cell loss. This effect is most pronounced when KGF is given after the radiation exposure. With regard to epithelial radiation tolerance, KGF-application in animal models results in a significant increase, by a factor of 1.7-2.3, in the doses required to induce epithelial ulceration as a clinically most relevant endpoint. After exposure with a given dose, this translates into a significant reduction of the clinical manifestation of the acute radiation sequelae. This effect is accompanied by a modification of the time course of the response. In conclusion, although the mechanisms underlying the protective efficacy remain unclear, KGF may represent an effective approach for amelioration of radiation effects in oral, gastrointestinal and cutaneous epithelia. Results from a clinical pilot study indicate that KGF is well tolerated and effective in humans. (orig.) [de

Radiation effects in brain and spinal cord

International Nuclear Information System (INIS)

Franke, H.D.; Lierse, W.

1978-01-01

Radiation sensitivity of both the brain and spinal cord in prenatal and postnatal stages, in infancy and adult age is represented also in consideration of a combined treatment with methotrexate. In adults, application of important doses of high-energy radiation increases the risk of injurious effects to the central nervous system. If the spinal cord is involved, more than 60% of the radiolesions have a progredient course ending with death. The pathogenesis and disposing factors are referred to, and the incidence of radiation necrosis with regard to age and sex, the degrees of injury and their frequence within different ranges of dosage are analyzed on the basis of data from universal literature. An examination of 'tolerance doses' for the spinal cord is made by means of Strandquist-diagrams and of the Ellis-formula. The slopes of regression lines are reported for various 'degrees of response' in skin, brain and spinal cord following radiation therapy. In the Strandquist-diagram, slopes of regression lines are dependent on the 'degree of response', flattening if skin and spinal cord are affected by radiation in the same degree, necroses having the same slope for both the organs. (orig./MG) [de

Expression of miRNA-26b-5p and its target TRPS1 is associated with radiation exposure in post-Chernobyl breast cancer.

Science.gov (United States)

Wilke, Christina M; Hess, Julia; Klymenko, Sergiy V; Chumak, Vadim V; Zakhartseva, Liubov M; Bakhanova, Elena V; Feuchtinger, Annette; Walch, Axel K; Selmansberger, Martin; Braselmann, Herbert; Schneider, Ludmila; Pitea, Adriana; Steinhilber, Julia; Fend, Falko; Bösmüller, Hans C; Zitzelsberger, Horst; Unger, Kristian

2018-02-01

Ionizing radiation is a well-recognized risk factor for the development of breast cancer. However, it is unknown whether radiation-specific molecular oncogenic mechanisms exist. We investigated post-Chernobyl breast cancers from radiation-exposed female clean-up workers and nonexposed controls for molecular changes. Radiation-associated alterations identified in the discovery cohort (n = 38) were subsequently validated in a second cohort (n = 39). Increased expression of hsa-miR-26b-5p was associated with radiation exposure in both of the cohorts. Moreover, downregulation of the TRPS1 protein, which is a transcriptional target of hsa-miR-26b-5p, was associated with radiation exposure. As TRPS1 overexpression is common in sporadic breast cancer, its observed downregulation in radiation-associated breast cancer warrants clarification of the specific functional role of TRPS1 in the radiation context. For this purpose, the impact of TRPS1 on the transcriptome was characterized in two radiation-transformed breast cell culture models after siRNA-knockdown. Deregulated genes upon TRPS1 knockdown were associated with DNA-repair, cell cycle, mitosis, cell migration, angiogenesis and EMT pathways. Furthermore, we identified the interaction partners of TRPS1 from the transcriptomic correlation networks derived from gene expression data on radiation-transformed breast cell culture models and sporadic breast cancer tissues provided by the TCGA database. The genes correlating with TRPS1 in the radiation-transformed breast cell lines were primarily linked to DNA damage response and chromosome segregation, while the transcriptional interaction partners in the sporadic breast cancers were mostly associated with apoptosis. Thus, upregulation of hsa-miR-26b-5p and downregulation of TRPS1 in radiation-associated breast cancer tissue samples suggests these molecules representing radiation markers in breast cancer. © 2017 UICC.

The association between breast tissue optical content and mammographic density in pre- and post-menopausal women.

Directory of Open Access Journals (Sweden)

Kristina M Blackmore

Full Text Available Mammographic density (MD, associated with higher water and lower fat content in the breast, is strongly related to breast cancer risk. Optical attenuation spectroscopy (OS is a non-imaging method of evaluating breast tissue composition by red and near-infrared light transmitted through the breast that, unlike mammography, does not involve radiation. OS provides information on wavelength dependent light scattering of tissue and on absorption by water, lipid, oxy-, deoxy-hemoglobin. We propose that OS could be an alternative marker of breast cancer risk and that OS breast tissue measures will be associated with MD. In the present analysis, we developed an algorithm to estimate breast tissue composition and light scattering parameters using a spectrally constrained global fitting procedure employing a diffuse light transport model. OS measurements were obtained from 202 pre- and post-menopausal women with normal mammograms. Percent density (PD and dense area (DA were measured using Cumulus. The association between OS tissue composition and PD and DA was analyzed using linear regression adjusted for body mass index. Among pre-menopausal women, lipid content was significantly inversely associated with square root transformed PD (β = -0.05, p = 0.0002 and DA (β = -0.05, p = 0.019; water content was significantly positively associated with PD (β = 0.06, p = 0.008. Tissue oxygen saturation was marginally inversely associated with PD (β = -0.03, p = 0.057 but significantly inversely associated with DA (β = -0.10, p = 0.002. Among post-menopausal women lipid and water content were significantly associated (negatively and positively, respectively with PD (β lipid = -0.08, β water = 0.14, both p<0.0001 and DA (β lipid = -0.10, p<0.0001; β water = 0.11, p = 0.001. The association between OS breast content and PD and DA is consistent with more proliferation in dense tissue of younger women, greater lipid content in low density tissue and higher water

Canine tumor and normal tissue response to heat and radiation

International Nuclear Information System (INIS)

Gillette, E.L.; McChesney, S.L.

1985-01-01

Oral squamous cell carcinomas of dogs were treated with either irradiation alone or combined with hyperthermia. Tumor control was assessed as no evidence of disease one year following treatment. Dogs were randomized to variable radiation doses which were given in ten fractions three times a week for three weeks. Heat was given three hours after the first and third radiation dose each week for seven treatments. The attempt was made to achieve a minimum tumor temperature of 42 0 C for thirty minutes with a maximum normal tissue temperature of 40 0 C. It was usually possible to selectively heat tumors. The TCD 50 for irradiation alone was about 400 rads greater than for heat plus irradiation. The dose response curve for heat plus radiation was much steeper than for radiation alone indicating less heterogeneity of tumor response. That also implies a much greater effectiveness of radiation combined with heat at higher tumor control probabilities. Early necrosis caused by heating healed with conservative management. No increase in late radiation necrosis was observed

Adverse event reporting and developments in radiation biology after normal tissue injury: International Atomic Energy Agency consultation

International Nuclear Information System (INIS)

Chen Yuhchyau; Trotti, Andy; Coleman, C. Norman; Machtay, Mitchell; Mirimanoff, Rene O.; Hay, John; O'Brien, Peter C.; El-Gueddari, Brahim; Salvajoli, Joao V.; Jeremic, Branislav

2006-01-01

Purpose: Recent research has enhanced our understanding of radiation injury at the molecular-cellular and tissue levels; significant strides have occurred in standardization of adverse event reporting in clinical trials. In response, the International Atomic Energy Agency, through its Division of Human Health and its section for Applied Radiation Biology and Radiotherapy, organized a consultation meeting in Atlanta (October 2, 2004) to discuss developments in radiobiology, normal tissue reactions, and adverse event reporting. Methods and Materials: Representatives from cooperative groups of African Radiation Oncology Group, Curriculo Radioterapeutica Ibero Latino Americana, European Organization for Research and Treatment of Cancer, National Cancer Institute of Canada Clinical Trials Group, Radiation Therapy Oncology Group, and Trans-Tasman Radiation Oncology Group held the meeting discussion. Results: Representatives of major radiotherapy groups/organizations and prominent leaders in radiotherapy discussed current understanding of normal tissue radiobiologic effects, the design and implementation of future clinical and translational projects for normal tissue injury, and the standardization of adverse-event reporting worldwide. Conclusions: The consensus was to adopt NCI comprehensive adverse event reporting terminology and grading system (CTCAE v3.0) as the new standard for all cooperative group trials. Future plans included the implementation of coordinated research projects focusing on normal tissue biomarkers and data collection methods

Late effects from particulate radiations in primate and rabbit tissues

Science.gov (United States)

Lett, J. T.; Cox, A. B.; Bergtold, D. S.; Lee, A. C.; Pickering, J. E.

Optic tissues in groups of New Zealand white rabbits were irradiated locally at different stages throughout the median life span of the species with a single dose (9 Gy) of 425 MeV/amu Ne ions (LET∞~30 keV/μm) and then inspected routinely for the progression of radiation cataracts. The level of early cataracts was found to be highest in the youngest group of animals irradiated (8 weeks old) but both the onset of late cataracts and loss of vision occurred earlier when animals were irradiated during the second half of the median life span. This age response can have serious implications in terms of space radiation hazards to man. Rhesus monkeys that had been subjected to whole-body skin irradiation (2.8 and 5.6 Gy) by 32 MeV protons (range in tissue ~ 1 cm) some twenty years previously were analysed for radiation damage by the propagation of skin fibroblasts in primary cultures. Such propagation from skin biopsies in MEM-α medium (serial cultivation) or in supplemented Ham's F-10 medium (cultivation without dilution) revealed late damage in the stem (precursor) cells of the skins of the animals. The proton fluxes employed in this experiment are representative of those occurring in major solar flares.

In vivo evidence for an endothelium-dependent mechanism in radiation-induced normal tissue injury

Science.gov (United States)

Rannou, Emilie; François, Agnès; Toullec, Aurore; Guipaud, Olivier; Buard, Valérie; Tarlet, Georges; Mintet, Elodie; Jaillet, Cyprien; Iruela-Arispe, Maria Luisa; Benderitter, Marc; Sabourin, Jean-Christophe; Milliat, Fabien

2015-01-01

The pathophysiological mechanism involved in side effects of radiation therapy, and especially the role of the endothelium remains unclear. Previous results showed that plasminogen activator inhibitor-type 1 (PAI-1) contributes to radiation-induced intestinal injury and suggested that this role could be driven by an endothelium-dependent mechanism. We investigated whether endothelial-specific PAI-1 deletion could affect radiation-induced intestinal injury. We created a mouse model with a specific deletion of PAI-1 in the endothelium (PAI-1KOendo) by a Cre-LoxP system. In a model of radiation enteropathy, survival and intestinal radiation injury were followed as well as intestinal gene transcriptional profile and inflammatory cells intestinal infiltration. Irradiated PAI-1KOendo mice exhibited increased survival, reduced acute enteritis severity and attenuated late fibrosis compared with irradiated PAI-1flx/flx mice. Double E-cadherin/TUNEL labeling confirmed a reduced epithelial cell apoptosis in irradiated PAI-1KOendo. High-throughput gene expression combined with bioinformatic analyses revealed a putative involvement of macrophages. We observed a decrease in CD68+cells in irradiated intestinal tissues from PAI-1KOendo mice as well as modifications associated with M1/M2 polarization. This work shows that PAI-1 plays a role in radiation-induced intestinal injury by an endothelium-dependent mechanism and demonstrates in vivo that the endothelium is directly involved in the progression of radiation-induced enteritis. PMID:26510580

Retroperitoneal soft tissue sarcoma: An analysis of radiation and surgical treatment

International Nuclear Information System (INIS)

Ballo, Matthew T.; Zagars, Gunar K.; Pollock, Raphael E.; Benjamin, Robert S.; Feig, Barry W.; Cormier, Janice N.; Hunt, Kelly K.; Patel, Shreyaskumar R.; Trent, Jonathan C.; Beddar, Sam; Pisters, Peter W.T.

2007-01-01

Purpose: To evaluate the clinical outcomes of patients with localized retroperitoneal soft tissue sarcoma (STS) treated with complete surgical resection and radiation. Methods and Materials: The medical records of 83 patients were reviewed retrospectively. Sixty patients presented with primary disease and the remaining 23 had recurrence after previous surgical resection. Results: With a median follow-up of 47 months, the actuarial overall disease-specific survival (DSS), distant metastasis-free survival, and local control (LC) rates were 44%, 67%, and 40%, respectively. Of the 38 patients dying of disease, local disease progression was the sole site of recurrence for 16 patients and was a component of progression for another 11 patients. Multivariate analysis indicated that histologic grade was associated with the 5-year rates of DSS (low-grade, 92%; intermediate-grade, 51%; and high-grade, 41%, p = 0.006). Multivariate analysis also indicated an inferior 5-year LC rate for patients presenting with recurrent disease, positive or uncertain resection margins, and age greater than 65 years. The data did not suggest an improved local control with higher doses of external-beam radiation (EBRT) or with the specific use of intraoperative radiotherapy (IORT). Radiation-related complications (10% at 5 years) developed in 5 patients; all had received their EBRT postoperatively. Conclusions: Although preoperative radiation therapy and aggressive surgical resection is well tolerated in patients, local disease progression continues to be a significant component of disease death. In this small cohort of patients, the use of higher doses of EBRT or IORT did not result in clinically apparent improvements in outcomes

Stem Cell Therapy to Reduce Radiation-Induced Normal Tissue Damage

NARCIS (Netherlands)

Coppes, Rob P.; van der Goot, Annemieke; Lombaert, Isabelle M. A.

Normal tissue damage after radiotherapy is still a major problem in cancer treatment. Stem cell therapy may provide a means to reduce radiation-induced side effects and improve the quality of life of patients. This review discusses the current status in stem cell research with respect to their

Responses of some normal tissues to low doses of γ-radiation

International Nuclear Information System (INIS)

Withers, H.R.

1975-01-01

The response of four normal tissues to low doses of γ-radiation was measured in mice using three indirect methods. The survival curves for cells of the tissues studied (colon, jejunum, testis and haemoleucopoietic system) may be exponential over an uncertain dose range (from zero to between 100 to 230 rad), the slope being about one third of that in the high-dose region. Some of the uncertainties in the data probably reflect variations in age-density distribution. (author)

Vitamin D Deficiency Is Associated With the Severity of Radiation-Induced Proctitis in Cancer Patients

International Nuclear Information System (INIS)

Ghorbanzadeh-Moghaddam, Amir; Gholamrezaei, Ali; Hemati, Simin

2015-01-01

Purpose: Radiation-induced injury to normal tissues is a common complication of radiation therapy in cancer patients. Considering the role of vitamin D in mucosal barrier hemostasis and inflammatory responses, we investigated whether vitamin D deficiency is associated with the severity of radiation-induced acute proctitis in cancer patients. Methods and Materials: This prospective observational study was conducted in cancer patients referred for pelvic radiation therapy. Serum concentration of 25-hydroxyvitamin D was measured before radiation therapy. Vitamin D deficiency was defined as 25-hydroxyvitamin D concentrations of <35 nmol/L and <40 nmol/L in male and female patients, respectively, based on available normative data. Acute proctitis was assessed after 5 weeks of radiation therapy (total received radiation dose of 50 Gy) and graded from 0 to 4 using Radiation Therapy Oncology Group (RTOG) criteria. Results: Ninety-eight patients (57.1% male) with a mean age of 62.8 ± 9.1 years were studied. Vitamin D deficiency was found in 57 patients (58.1%). Symptoms of acute proctitis occurred in 72 patients (73.4%) after radiation therapy. RTOG grade was significantly higher in patients with vitamin D deficiency than in normal cases (median [interquartile range] of 2 [0.5-3] vs 1 [0-2], P=.037). Vitamin D deficiency was associated with RTOG grade of ≥2, independent of possible confounding factors; odds ratio (95% confidence interval) = 3.07 (1.27-7.50), P=.013. Conclusions: Vitamin D deficiency is associated with increased severity of radiation-induced acute proctitis. Investigating the underlying mechanisms of this association and evaluating the effectiveness of vitamin D therapy in preventing radiation-induced acute proctitis is warranted

Vitamin D Deficiency Is Associated With the Severity of Radiation-Induced Proctitis in Cancer Patients

Energy Technology Data Exchange (ETDEWEB)

Ghorbanzadeh-Moghaddam, Amir [Medical Student' s Research Center, Isfahan University of Medical Sciences, Isfahan (Iran, Islamic Republic of); Gholamrezaei, Ali, E-mail: Gholamrezaei@med.mui.ac.ir [Medical Student' s Research Center, Isfahan University of Medical Sciences, Isfahan (Iran, Islamic Republic of); Poursina Hakim Research Institution, Isfahan (Iran, Islamic Republic of); Hemati, Simin [Department of Radiotherapy Oncology, Isfahan University of Medical Sciences, Isfahan (Iran, Islamic Republic of)

2015-07-01

Purpose: Radiation-induced injury to normal tissues is a common complication of radiation therapy in cancer patients. Considering the role of vitamin D in mucosal barrier hemostasis and inflammatory responses, we investigated whether vitamin D deficiency is associated with the severity of radiation-induced acute proctitis in cancer patients. Methods and Materials: This prospective observational study was conducted in cancer patients referred for pelvic radiation therapy. Serum concentration of 25-hydroxyvitamin D was measured before radiation therapy. Vitamin D deficiency was defined as 25-hydroxyvitamin D concentrations of <35 nmol/L and <40 nmol/L in male and female patients, respectively, based on available normative data. Acute proctitis was assessed after 5 weeks of radiation therapy (total received radiation dose of 50 Gy) and graded from 0 to 4 using Radiation Therapy Oncology Group (RTOG) criteria. Results: Ninety-eight patients (57.1% male) with a mean age of 62.8 ± 9.1 years were studied. Vitamin D deficiency was found in 57 patients (58.1%). Symptoms of acute proctitis occurred in 72 patients (73.4%) after radiation therapy. RTOG grade was significantly higher in patients with vitamin D deficiency than in normal cases (median [interquartile range] of 2 [0.5-3] vs 1 [0-2], P=.037). Vitamin D deficiency was associated with RTOG grade of ≥2, independent of possible confounding factors; odds ratio (95% confidence interval) = 3.07 (1.27-7.50), P=.013. Conclusions: Vitamin D deficiency is associated with increased severity of radiation-induced acute proctitis. Investigating the underlying mechanisms of this association and evaluating the effectiveness of vitamin D therapy in preventing radiation-induced acute proctitis is warranted.

Low skeletal muscle radiation attenuation and visceral adiposity are associated with overall survival and surgical site infections in patients with pancreatic cancer.

Science.gov (United States)

van Dijk, David P J; Bakens, Maikel J A M; Coolsen, Mariëlle M E; Rensen, Sander S; van Dam, Ronald M; Bours, Martijn J L; Weijenberg, Matty P; Dejong, Cornelis H C; Olde Damink, Steven W M

2017-04-01

Cancer cachexia and skeletal muscle wasting are related to poor survival. In this study, quantitative body composition measurements using computed tomography (CT) were investigated in relation to survival, post-operative complications, and surgical site infections in surgical patients with cancer of the head of the pancreas. A prospective cohort of 199 patients with cancer of the head of the pancreas was analysed by CT imaging at the L3 level to determine (i) muscle radiation attenuation (average Hounsfield units of total L3 skeletal muscle); (ii) visceral adipose tissue area; (iii) subcutaneous adipose tissue area; (iv) intermuscular adipose tissue area; and (v) skeletal muscle area. Sex-specific cut-offs were determined at the lower tertile for muscle radiation attenuation and skeletal muscle area and the higher tertile for adipose tissues. These variables of body composition were related to overall survival, severe post-operative complications (Dindo-Clavien ≥ 3), and surgical site infections (wounds inspected daily by an independent trial nurse) using Cox-regression analysis and multivariable logistic regression analysis, respectively. Low muscle radiation attenuation was associated with shorter survival in comparison with moderate and high muscle radiation attenuation [median survival 10.8 (95% CI: 8.8-12.8) vs. 17.4 (95% CI: 14.7-20.1), and 18.5 (95% CI: 9.2-27.8) months, respectively; P site infection rate, OR: 2.4 (95% CI: 1.1-5.3; P = 0.027). Low muscle radiation attenuation was associated with reduced survival, and high visceral adiposity was associated with an increase in surgical site infections. The strong correlation between muscle radiation attenuation and intermuscular adipose tissue suggests the presence of ectopic fat in muscle, warranting further investigation. CT image analysis could be implemented in pre-operative risk assessment to assist in treatment decision-making. © 2016 The Authors. Journal of Cachexia, Sarcopenia and Muscle

A case report of radiation-osteomyelitis 9 years after irradiation for thymoma

International Nuclear Information System (INIS)

Ohkubo, Ken-ichi; Itoi, Kazumi; Yanagihara, Kazuhiro; Matsuoka, Katsunari; Kuwabara, Masayoshi

1992-01-01

Radiation-osteomyelitis of the sternum is rare and usually difficult to cure. A 75-year-old man, who had undergone an exploratory sternotomy for a mediastinal tumor, not resected after all, 9 years earlier and received radiation therapy successively for the histological diagnosis of malignant thymoma, was admitted to our hospital with the chief complaint of fever and pus discharge of the anterior chest wall. He also suffered from diabetes mellitus. The skin around the fistula was dark-red and atrophic due to irradiation dermatitis and the manubrium was fissured in the midline. Open drainage and two-stage operation of direct closure was tried in vain. This case was treated succesfully by resection of necrosed portion of sternum and pectoral muscle flap closure. (author)

Effect-independent measures of tissue response to fractionated radiation

International Nuclear Information System (INIS)

Thames, H.D.

1984-01-01

Tissue repair factors are measures of sparing from dose fractionation, in the absence of proliferation. A desirable feature of any repair factor is that it be independent of the level of injury induced in the tissue, since otherwise the comparison of tissues on the basis of the factor would not be meaningful. The repair factors F/sub R/ and F/sub rec/ are increasing functions of D/sub 1/, and depend on level of skin reaction after fractionated radiation. By contrast, β/α is effect-independent as a measure of repair capacity in skin, gut, and bone marrow. For late fibrotic reactions in the kidney, there was an increase in β/α with increased levels of injury that was statistically insignificant. The halftime, T/sub 1/2/, for intracellular repair processes in tissues is a measure of repair kinetics. Effect-independence is defend for T/sub 1/2/ as independence from size of dose per fraction. T/sub 1/2/ is independent of fraction size in skin, gut, and spinal cord, and is longer (1.5 hours) in the late-reacting tissues (lung and spinal cord) than in those that react acutely (less than 1 hour), with skin as the exception (1.3 hours). Therefore, early and late-responding normal tissues may be distinguished in terms of both repair capacity and repair kinetics: repair is slower in late-responding tissues, which are also more sensitive to changes in dose fractionation

Detection of ultraviolet radiation using tissue equivalent radiochromic gel materials

International Nuclear Information System (INIS)

Bero, M A; Abukassem, I

2009-01-01

Ferrous Xylenol-orange Gelatin gel (FXG) is known to be sensitive to ionising radiation such as γ and X-rays. The effect of ionising radiation is to produce an increase in the absorption over a wide region of the visible spectrum, which is proportional to the absorbed dose. This study demonstrates that FXG gel is sensitive to ultraviolet radiation and therefore it could functions as UV detector. Short exposure to UV radiation produces linear increase in absorption measured at 550nm, however high doses of UV cause the ion indicator colour to fad away in a manner proportional to the incident UV energy. Light absorbance increase at the rate of 1.1% per minute of irradiation was monitored. The exposure level at which the detector has linear response is comparable to the natural summer UV radiation. Evaluating the UV ability to pass through tissue equivalent gel materials shows that most of the UV gets absorbed in the first 5mm of the gel materials, which demonstrate the damaging effects of this radiation type on human skin and eyes. It was concluded that FXG gel dosimeter has the potential to offer a simple, passive ultraviolet radiation detector with sensitivity suitable to measure and visualises the natural sunlight UV exposure directly by watching the materials colour changes.

Detection of ultraviolet radiation using tissue equivalent radiochromic gel materials

Science.gov (United States)

Bero, M. A.; Abukassem, I.

2009-05-01

Ferrous Xylenol-orange Gelatin gel (FXG) is known to be sensitive to ionising radiation such as γ and X-rays. The effect of ionising radiation is to produce an increase in the absorption over a wide region of the visible spectrum, which is proportional to the absorbed dose. This study demonstrates that FXG gel is sensitive to ultraviolet radiation and therefore it could functions as UV detector. Short exposure to UV radiation produces linear increase in absorption measured at 550nm, however high doses of UV cause the ion indicator colour to fad away in a manner proportional to the incident UV energy. Light absorbance increase at the rate of 1.1% per minute of irradiation was monitored. The exposure level at which the detector has linear response is comparable to the natural summer UV radiation. Evaluating the UV ability to pass through tissue equivalent gel materials shows that most of the UV gets absorbed in the first 5mm of the gel materials, which demonstrate the damaging effects of this radiation type on human skin and eyes. It was concluded that FXG gel dosimeter has the potential to offer a simple, passive ultraviolet radiation detector with sensitivity suitable to measure and visualises the natural sunlight UV exposure directly by watching the materials colour changes.

Mammalian Tissue Response to Low Dose Ionizing Radiation: The Role of Oxidative Metabolism and Intercellular Communication

Energy Technology Data Exchange (ETDEWEB)

Azzam, Edouard I

2013-01-16

The objective of the project was to elucidate the mechanisms underlying the biological effects of low dose/low dose rate ionizing radiation in organs/tissues of irradiated mice that differ in their susceptibility to ionizing radiation, and in human cells grown under conditions that mimic the natural in vivo environment. The focus was on the effects of sparsely ionizing cesium-137 gamma rays and the role of oxidative metabolism and intercellular communication in these effects. Four Specific Aims were proposed. The integrated outcome of the experiments performed to investigate these aims has been significant towards developing a scientific basis to more accurately estimate human health risks from exposures to low doses ionizing radiation. By understanding the biochemical and molecular changes induced by low dose radiation, several novel markers associated with mitochondrial functions were identified, which has opened new avenues to investigate metabolic processes that may be affected by such exposure. In particular, a sensitive biomarker that is differentially modulated by low and high dose gamma rays was discovered.

Evaluation of laser radiation regimes at thermal tissue destruction

Science.gov (United States)

Ivanov, Anatoly; Kazaryan, Mishik A.; Molodykh, E. I.; Shchetinkina, T. A.

1996-01-01

The existing methods of laser destruction of biotissues, widely spread in surgery and coagulation action, are based on local heat emission in the tissues after light absorption. Here we present the results of the simulation of tissues heat destruction, taking into account the influence of blood and lymph circulation on the processes of heat transfer. The problem is adapted to the case of liver tissue with tumor. A liver is considered as a capillary-porous body with internal blood circulation. Heatconductivity and tissue-blood heat transfer are considered. Heat action is assumed to be implemented with contact laser scalpel. The mathematical model consists of two inhomogeneous nonlinear equations of heatconductivity with spherical symmetry. Nonstationary temperature fields of tissue and blood are determined and the main parameters are: (1) coefficients of heatconductivity and capacitance of blood and tissue, (2) blood and tissue density, (3) total metabolic energy, (4) volume coefficient accounting for heat-exchange between tissue and blood, and (5) blood circulation velocity. The power of laser radiation was taken into account in boundary conditions set for the center of coagulated tissue volume. We also took into account the process connected with changing of substance phase (vaporization). The original computer programs allow one to solve the problem varying in a wide range of the main parameters. Reasonable agreement was found between the calculation results and the experimental data for operations on microsamples and on test animals. It was demonstrated, in particular, that liver tissue coagulation regime is achieved at 10 W laser power during 25 s. The coagulation radius of 0.7 cm with the given tumor radius of 0.5 cm corresponds to the real clinical situation in case of metastasis liver affection.

A novel radiation responsive cis-acting element regulates gene induction and mediates tissue injury

International Nuclear Information System (INIS)

Hallahan, Dennis E.; Virudachalam, Subbulakshmi; Kuchibahtla, Jaya

1997-01-01

Purpose: The intracellular adhesion molecule (ICAM-1) binds and activates inflammatory cells and thereby contributes to the pathogenesis of tissue injury. To characterize a model for radiation-induction of tissue injury, we studied radiation-mediated lung injury in mice deficient in the ICAM-1 gene. To study the mechanisms of x-ray mediated ICAM induction, we studied transcriptional activation of the ICAM promoter and nuclear protein binding to the 5' untranslated region of the ICAM gene. Methods: Immunohistochemistry and immunofluorescence were used to study the histologic pattern of ICAM expression in irradiated tissue. The ICAM-1 knockout mice were bred with wild type mice to create heterozygous mice with attenuated ICAM expression. ICAM -/-, ICAM+/- and ICAM +/+ mice were treated with thoracic irradiation and lung sections were stained for leukocyte common antigen (CD45) to study inflammation. To study the mechanism of x-ray induction of ICAM, we linked the 5' untranslated region of the ICAM gene to the luciferase reporter gene and delated DNA segments from the promoter to determine which elements are required for induction. We performed electrophoretic mobility shift analysis of nuclear proteins from irradiated endothelial cells to study transcription factor activation. Results: Immunohistochemistry showed dose and time dependent increases in ICAM protein expression in irradiated lungs which was prolonged as compared to endothelial cells in vitro. The histologic pattern of ICAM expression was in the capillary endothelium and was distinct from the pattern of expression of other radiation-inducible adhesion molecules. ICAM knockout mice had no ICAM expression and no inflammatory cell accumulation in the irradiated lung. ICAM+/+ mice developed leukocyte adhesion to irradiated endothelium within hours of irradiation and radiation pneumonitis 5 to 6 weeks later. The DNA sequence between -981 and -769 (relative to start codon) contains two 16-base pair repeats, each

Generation of radicals in hard biological tissues under the action of laser radiation

Science.gov (United States)

Sviridov, Alexander P.; Bagratashvili, Victor N.; Sobol, Emil N.; Omelchenko, Alexander I.; Lunina, Elena V.; Zhitnev, Yurii N.; Markaryan, Galina L.; Lunin, Valerii V.

2002-07-01

The formation of radicals upon UV and IR laser irradiation of some biological tissues and their components was studied by the EPR technique. The radical decay kinetics in body tissue specimens after their irradiation with UV light were described by various models. By the spin trapping technique, it was shown that radicals were not produced during IR laser irradiation of cartilaginous tissue. A change in optical absorption spectra and the dynamics of optical density of cartilaginous tissue, fish scale, and a collagen film under exposure to laser radiation in an air, oxygen, and nitrogen atmosphere was studied.

Influence of low-energy laser radiation on normal skin and certain tumor tissues

Energy Technology Data Exchange (ETDEWEB)

Pletnev, S.D.; Karpenko, O.M.

For some years, the authors' Institute has studied the influence of various types of low-energy laser radiation on normal tissue and the growth of tumors. Radiation at 3 and 30 J/cm/sup 2/ causes an increase in biological activity of various cell elements, manifested as an increase in mitotic activity of the cells in the basal layer of the epidermis, conglomeration of chromatin in the cell nuclei and an increase in degranulation of fat cells in the process of their migration to the reticular layer. Also noted was an increase in content of fibroblastic and lymphohistocytic elements in the dermis, as well as an increase in collagenization of connective tissue. It was found that irradiation of the skin by helium-neon, cadmium-helium and nitrogen lasers before and after grafting of the cells of various tumors modifies the course of the tumor process. This effect is apparently related to the fact that systematic irradiation results in changes creating a favorable background for survival and proliferation of tumor cells in the skin tissue medium. The changes facilitate an increase in survival and growth of both pigmented and nonpigmented tumors. Low power radiation stimulates the activity of the cells or cell structures; medium power stimulates their activity; high power suppresses activity.

Preradiation dental extractions and the incidence of bone necrosis

International Nuclear Information System (INIS)

Beumer, J.; Harrison, R.; Sanders, B.; Kurrasch, M.

1983-01-01

Studies were done with 120 patients submitting to preradiation dental extraction within the radiation treatment volume. Bone necroses developed at the extraction sites in 17 patients (14.1%). The risk of bone necrosis in these patients is primarily dependent upon the size of the radiation treatment volume, radiation dose to mandibular bone, and healing time for the extraction wounds. Of the 13 mandibular bone necroses occurring at preradiation extraction sites, only two have not responded favorably to conservative management. Our data indicates that a policy of selected tooth removal, before radiation treatment, will minimize the risk of osteoradionecrosis. Mandibular molars with advanced chronic periodontal bone loss, residing within the proposed radiation field should be considered for removal before commencement of radiation treatment

A Preliminary Study on Racial Differences in HMOX1, NFE2L2, and TGFβ1 Gene Polymorphisms and Radiation-Induced Late Normal Tissue Toxicity

International Nuclear Information System (INIS)

Alam, Asim; Mukhopadhyay, Nitai D.; Ning, Yi; Reshko, Leonid B.; Cardnell, Robert J.G.; Alam, Omair; Rabender, Christopher S.; Yakovlev, Vasily A.; Walker, Linda; Anscher, Mitchell S.; Mikkelsen, Ross B.

2015-01-01

Purpose: This study tested whether racial differences in genetic polymorphisms of 4 genes involved in wound repair and response to radiation can be used to predict the occurrence of normal tissue late effects of radiation therapy and indicate potential therapeutic targets. Methods and Materials: This prospective study examined genetic polymorphisms that modulate the expression of 4 genes involved in inflammation and fibrosis and response to radiation (HMOX1, NFE2L2, NOS3, and TGFβ1). DNA from blood samples of 179 patients (∼80% breast and head and neck) collected at the time of diagnosis by their radiation oncologist as exhibiting late normal tissue toxicity was used for the analysis. Patient demographics were as follows: 56% white, 43% African American, 1% other. Allelic frequencies of the different polymorphisms of the participants were compared with those of the general American population stratified by race. Twenty-six additional patients treated with radiation, but without toxicity at 3 months or later after therapy, were also analyzed. Results: Increased frequency of a long GT repeat in the HMOX1 promoter was associated with late effects in both African American and white populations. The single nucleotide polymorphisms (SNP) rs1800469 in the TGFβ1 promoter and the rs6721961 SNP in the NFE2L2 promoter were also found to significantly associate with late effects in African Americans but not whites. A combined analysis of these polymorphisms revealed that >90% of African American patients with late effects had at least 1 of these minor alleles, and 58% had 2 or more. No statistical significance was found relating the studied NOS3 polymorphisms and normal tissue toxicity. Conclusions: These results support a strong association between wound repair and late toxicities of radiation. The presence of these genetic risk factors can vary significantly among different ethnic groups, as demonstrated for some of the SNPs. Future studies should account for the

A Preliminary Study on Racial Differences in HMOX1, NFE2L2, and TGFβ1 Gene Polymorphisms and Radiation-Induced Late Normal Tissue Toxicity

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Alam, Asim [Department of Radiation Oncology, Virginia Commonwealth University, Richmond, Virginia (United States); Mukhopadhyay, Nitai D. [Department of Biostatistics, Virginia Commonwealth University, Richmond, Virginia (United States); Ning, Yi [Department of Family Medicine and Population Health, Virginia Commonwealth University, Richmond, Virginia (United States); Reshko, Leonid B.; Cardnell, Robert J.G.; Alam, Omair; Rabender, Christopher S.; Yakovlev, Vasily A.; Walker, Linda; Anscher, Mitchell S. [Department of Radiation Oncology, Virginia Commonwealth University, Richmond, Virginia (United States); Mikkelsen, Ross B., E-mail: rmikkels@vcu.edu [Department of Radiation Oncology, Virginia Commonwealth University, Richmond, Virginia (United States)

2015-10-01

Purpose: This study tested whether racial differences in genetic polymorphisms of 4 genes involved in wound repair and response to radiation can be used to predict the occurrence of normal tissue late effects of radiation therapy and indicate potential therapeutic targets. Methods and Materials: This prospective study examined genetic polymorphisms that modulate the expression of 4 genes involved in inflammation and fibrosis and response to radiation (HMOX1, NFE2L2, NOS3, and TGFβ1). DNA from blood samples of 179 patients (∼80% breast and head and neck) collected at the time of diagnosis by their radiation oncologist as exhibiting late normal tissue toxicity was used for the analysis. Patient demographics were as follows: 56% white, 43% African American, 1% other. Allelic frequencies of the different polymorphisms of the participants were compared with those of the general American population stratified by race. Twenty-six additional patients treated with radiation, but without toxicity at 3 months or later after therapy, were also analyzed. Results: Increased frequency of a long GT repeat in the HMOX1 promoter was associated with late effects in both African American and white populations. The single nucleotide polymorphisms (SNP) rs1800469 in the TGFβ1 promoter and the rs6721961 SNP in the NFE2L2 promoter were also found to significantly associate with late effects in African Americans but not whites. A combined analysis of these polymorphisms revealed that >90% of African American patients with late effects had at least 1 of these minor alleles, and 58% had 2 or more. No statistical significance was found relating the studied NOS3 polymorphisms and normal tissue toxicity. Conclusions: These results support a strong association between wound repair and late toxicities of radiation. The presence of these genetic risk factors can vary significantly among different ethnic groups, as demonstrated for some of the SNPs. Future studies should account for the

Head and neck soft tissue sarcomas treated with radiation therapy

Directory of Open Access Journals (Sweden)

Lucas K. Vitzthum

2016-06-01

Full Text Available Head and neck soft tissue sarcomas (HNSTSs are rare and heterogeneous cancers in which radiation therapy (RT has an important role in local tumor control (LC. The purpose of this study was to evaluate outcomes and patterns of treatment failure in patients with HNSTS treated with RT. A retrospective review was performed of adult patients with HNSTS treated with RT from January 1, 1998, to December 31, 2012. LC, locoregional control (LRC, disease-free survival (DFS, overall survival (OS, and predictors thereof were assessed. Forty-eight patients with HNSTS were evaluated. Five-year Kaplan-Meier estimates of LC, LRC, DFS, and OS were 87, 73, 63, and 83%, respectively. Angiosarcomas were found to be associated with worse LC, LRC, DFS, and OS. Patients over the age of 60 had lower rates of DFS. HNSTSs comprise a diverse group of tumors that can be managed with various treatment regimens involving RT. Angiosarcomas have higher recurrence and mortality rates.

Bronchus-associated lymphoid tissue in pulmonary hypertension produces pathologic autoantibodies.

Science.gov (United States)

Colvin, Kelley L; Cripe, Patrick J; Ivy, D Dunbar; Stenmark, Kurt R; Yeager, Michael E

2013-11-01

Autoimmunity has long been associated with pulmonary hypertension. Bronchus-associated lymphoid tissue plays important roles in antigen sampling and self-tolerance during infection and inflammation. We reasoned that activated bronchus-associated lymphoid tissue would be evident in rats with pulmonary hypertension, and that loss of self-tolerance would result in production of pathologic autoantibodies that drive vascular remodeling. We used animal models, histology, and gene expression assays to evaluate the role of bronchus-associated lymphoid tissue in pulmonary hypertension. Bronchus-associated lymphoid tissue was more numerous, larger, and more active in pulmonary hypertension compared with control animals. We found dendritic cells in and around lymphoid tissue, which were composed of CD3(+) T cells over a core of CD45RA(+) B cells. Antirat IgG and plasma from rats with pulmonary hypertension decorated B cells in lymphoid tissue, resistance vessels, and adventitia of large vessels. Lymphoid tissue in diseased rats was vascularized by aquaporin-1(+) high endothelial venules and vascular cell adhesion molecule-positive vessels. Autoantibodies are produced in bronchus-associated lymphoid tissue and, when bound to pulmonary adventitial fibroblasts, change their phenotype to one that may promote inflammation. Passive transfer of autoantibodies into rats caused pulmonary vascular remodeling and pulmonary hypertension. Diminution of lymphoid tissue reversed pulmonary hypertension, whereas immunologic blockade of CCR7 worsened pulmonary hypertension and hastened its onset. Bronchus-associated lymphoid tissue expands in pulmonary hypertension and is autoimmunologically active. Loss of self-tolerance contributes to pulmonary vascular remodeling and pulmonary hypertension. Lymphoid tissue-directed therapies may be beneficial in treating pulmonary hypertension.

Effects of mineral water differing in chemical composition on the post-radiation restorative processes of tissues

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Zubkova, S.M.; Bulyakova, N.V.; Azarova, V.S.; Popova, M.F.; Korolev, Yu.N.; Nikulina, L.A.; Panova, L.N. [Russian Research Center for Rehabilitation and Physiotherapy, Moscow (Russian Federation)]|[Severtsov Institute of Evolutionary Morphology and Animal Ecology, Moscow (Russian Federation)

1994-11-01

Experiments have show that natural and manufactured water containing arsenic and iodine may alter radiosensitivity in rats. This effect is associated with the ability of certain concentrations of iodine and arsenic ions to decrease respiration and stimulate phosphorylation in rat liver mintochondria, with resulting tissue hypoxia. Combination of iodine and calcium produced a protective effect after 21 days of daily administration to rats that absorbed radiation. In particular the survival rate of the rates increased to 67% in comparison with a 36% survival rate in rats that received only calcium and a 100% death rate in rats which were left untreated. In addition to increased energization of rat liver mitochondria, the treatment produced an inhibition of renal parenchyma clacification caused by radiation. 6 refs., 2 figs., 2 tabs.

Mechanical analysis of bone rulers sterilized by gamma radiation for use in tissue banks

International Nuclear Information System (INIS)

Kosmiskas, Luis Otavio Carvalho

2007-01-01

In the production process of health care products, contamination must be considered as one of the principal hazards to be avoided. Among the developed methods for sterilization, ionizing radiation has largely been used by many sectors in health care area as it is efficient in eliminating biological contaminants of several origins. The difficulty of deploying ionizing radiation in materials of human origin, though, includes which possible alterations it might cause in human tissue. In the present work, the extension of the bio mechanical alteration generated by radiation in bone tissue was evaluated by bio mechanical methods. More specifically, we evaluated alterations to the elastic modulus, rupture tension and percentage of deformation that are thought to be a consequence of the sterilization process. As a research model, bovine femur struts obtained from the diaphysis were used. The struts were frozen in a temperature of -70 deg C and irradiated with crescent doses of gamma radiation (0, 12.5, 25 e 50 kGy). During this work, a cutting system to obtain precision samples to use in such essays was developed. As results show that there is a significant different between the analyzed characteristics in the different doses of radiation. (author)

Establishment of an animal model of mice with radiation- injured soft tissue blood vessels

International Nuclear Information System (INIS)

Wang Daiyou; Yu Dahai; Wu Jiaxiao; Wei Shanliang; Wen Yuming

2004-01-01

Objective: The aim of this study was to establish an animal model of mice with radiation-injured soft tissue blood vessels. Methods: Forty male mice were irradiated with 30 Gy on the right leg. After the irradiation was finished each of the 40 male mice was tested with angiography, and its muscle tissues on the bilateral legs were examined with vessel staining assay and electron microscopy. Results: The results showed that the number of vessels on the right leg was less than that on the left leg, the microvessel density, average diameter and average sectional area of the right leg were all lower than those of the left, and the configuration and ultra-structure of vessels were also different between both sides of legs. Conclusion: In the study authors successfully established an animal model of mice with radiation-injured soft tissue blood vessels

Evaluation of DNA damage induced by gamma radiation in gill and muscle tissues of Cyprinus carpio and their relative sensitivity.

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M K, Praveen Kumar; Shyama, Soorambail K; D'Costa, Avelyno; Kadam, Samit B; Sonaye, Bhagatsingh Harisingh; Chaubey, Ramesh Chandra

2017-10-01

The effect of radiation on the aquatic environment is of major concern in recent years. Limited data is available on the genotoxicity of gamma radiation on different tissues of aquatic organisms. Hence, the present investigation was carried out to study the DNA damage induced by gamma radiation in the gill and muscle tissues and their relative sensitivity using the comet assay in the freshwater teleost fish, common carp (Cyprinus carpio). The comet assay was optimized and validated in common carp using cyclophosphamide (CP), a reference genotoxic agent. The fish were exposed (acute) to various doses of gamma radiation (2, 4, 6, 8 and 10Gy) and samplings (gill and muscle tissue) were done at regular intervals (24, 48 and 72h) to assess the DNA damage. A significant increase in DNA damage was observed as indicated by an increase in % tail DNA for all doses of gamma radiation in both tissues. We also observed a dose-related increase and a time-dependent decrease of DNA damage. In comparison, DNA damage showed different sensitivity among the tissues at different doses. This shows that a particular dose may have different effects on different tissues which could be due to physiological factors of the particular tissue. Our study also suggests that the gills and muscle of fish are sensitive and reliable tissues for evaluating the genotoxic effects of reference and environmental agents, using the comet assay. Copyright © 2017. Published by Elsevier Inc.

A case of primary mucosa-associated lymphoid tissue lymphoma of the vagina.

Science.gov (United States)

Yoshinaga, Kousuke; Akahira, Jun-Ichi; Niikura, Hitoshi; Ito, Kiyoshi; Moriya, Takuya; Murakami, Takashi; Kameoka, Jun-Ichi; Ichinohasama, Ryo; Okamura, Kunihiro; Yaegashi, Nobuo

2004-09-01

We report the first case of primary mucosa-associated lymphoid tissue (MALT) lymphoma of the vagina, the diagnosis of which is supported by genetic and immunophenotypic studies. A 65-year-old, para 2 woman presented to our hospital in July 1997 with a history of prolonged vaginal discharge. Although cytologic examination suggested possible malignancy, a biopsy of the vaginal wall was diagnosed as chronic inflammation. In June 2000, she underwent gynecologic examination because of anuria. Excisional biopsy revealed subepithelial infiltration of atypical lymphoid cells that stained for CD20, CD79a, and BCL-2; stained weakly for IgM; and did not stain for CD3, CD5, CD7, CD10, CD56, CD23, and IgD, suggesting marginal zone B-cell lineage. Monoclonality was detected by Southern blot analysis, and this patient was finally diagnosed as having primary MALT lymphoma of the vagina. She received 3 cycles of chemotherapy (THP-COP) and concurrent radiation to the whole pelvis. The patient is alive and well 40 months after treatment. Because the vagina is one of the mucosa-associated tissues, MALT lymphoma, though rare, must be included in the differential diagnosis of the vaginal neoplasms.

Bizarre (pseudomalignant) granulation-tissue reactions following ionizing-radiation exposure. A microscopic, immunohistochemical, and flow-cytometric study

International Nuclear Information System (INIS)

Weidner, N.; Askin, F.B.; Berthrong, M.; Hopkins, M.B.; Kute, T.E.; McGuirt, F.W.

1987-01-01

Two patients developed extremely bizarre (pseudomalignant) granulation-tissue reactions in the larynx and facial sinuses, following radiation therapy for carcinoma. Containing pleomorphic spindle cells and numerous (sometimes atypical) mitotic figures, both tumefactive lesions simulated high grade malignancies. While the pleomorphic cells contained vimentin immunoreactivity, they were nonreactive for low or high molecular weight keratin. Flowcytometric study of paraffin-embedded tissues revealed DNA indexes of 0.75 and 1.0. Neither recurred locally nor spread distantly after therapy. Their granulation-tissue growth pattern, and the presence of stromal and endothelial cells showing similar degrees of cytologic atypia were central to their recognition as benign. These findings show that severely atypical, sometimes aneuploid, granulation-tissue reactions can occur following radiation exposure. Care should be taken not to misinterpret these lesions as malignant

Protective effect of hydroferrate fluid, MRN-100, against lethality and hematopoietic tissue damage in γ-radiated Nile tilapia, Oreochromis niloticus

International Nuclear Information System (INIS)

Ghoneum, Mamdooh; Elbaghdady, Heba Allah M.; El-Shebly, Abdallah A.; Pan, Deyu; Assanah, Edward; Lawson, Greg

2013-01-01

Hydroferrate fluid, MRN-100, an iron-based compound derived from bivalent and trivalent ferrates, is a potent antioxidant compound. Therefore, we examined the protective effect of MRN-100 against γ-radiation-induced lethality and damage to hematopoietic tissues in fish. A total of 216 Nile tilapia fish (Oreochromis niloticus) were randomly divided into four groups. Group 1 served as a control that was administered no radiation and no MRN-100 treatment. Group 2 was exposed only to γ-radiation (15 Gy). Groups 3 and 4 were pre-treated with MRN-100 at doses of either 1 ml/l or 3 ml/l in water for 1 week, and subsequently exposed to radiation while continuing to receive MRN-100 for 27 days. The survival rate was measured, and biochemical and histopathological analyses of hematopoietic tissues were performed for the different treatment groups at 1 and 4 weeks post-radiation. Exposure to radiation reduced the survival rate to 27.7%, while treatment with MRN-100 maintained the survival rate at 87.2%. In addition, fish exposed to γ-radiation for 1 week showed a significant decrease in the total number of white blood cells (WBCs) and red blood cells (RBCs) series. However, treatment with MRN-100 protected the total WBC count and the RBCs series when compared with irradiated fish. Furthermore, significant histological lesions were observed in the hepatopancreas, spleen and gills of irradiated fish. However, treatment with MRN-100 protected the histopathology of various organs. We conclude that MRN-100 is a radioprotective agent in fish and may be useful as an adjuvant treatment to counteract the adverse side effects associated with radiation exposure. (author)

Identification of molecular mechanisms of radiation-induced vascular damage in normal tissues using microarray analyses

International Nuclear Information System (INIS)

Kruse, J.J.C.M.; Te Poele, J.A.M.; Russell, N.S.; Boersma, L.J.; Stewart, F.A.

2003-01-01

Radiation-induced telangiectasia, characterized by thin-walled dilated blood vessels, can be a serious late complication in patients that have been previously treated for cancer. It might cause cosmetic problems when occurring in the skin, and excessive bleeding requiring surgery when occurring in rectal mucosa. The mechanisms underlying the development of radiation-induced telangiectasia are unclear. The aim of the present study is to determine whether microarrays are useful for studying mechanisms of radiation-induced telangiectasia. The second aim is to test the hypotheses that telangiectasia is characterized by a final common pathway in different tissues. Microarray experiments were performed using amplified RNA from (sham)irradiated mouse tissues (kidney, rectum) at different intervals (1-30 weeks) after irradiation. After normalization procedures, the differentially expressed genes were identified. Control/repeat experiments were done to confirm that the observations were not artifacts of the array procedure. The mouse kidney experiments showed significant upregulation of 31 and 42 genes and downregulation of 9 and 4 genes at 10 and 20 weeks after irradiation, respectively. Irradiated mouse rectum has 278 upregulated and 537 downregulated genes at 10 weeks and 86 upregulated and 29 downregulated genes at 20 weeks. During the development of telangiectasia, 19 upregulated genes and 5 downregulated genes were common to both tissues. Upregulation of Jagged-1, known to play a role in angiogenesis, is particularly interesting in the context of radiation-induced telangiectasia. Microarrays are affective discovery tools to identify novel genes of interest, which may be involved in radiation-induced normal tissue injury. Using information from control arrays (particularly straight color, color reverse and self-self experiments) allowed for a more accurate and reproducible identification of differentially expressed genes than the selection of an arbitrary 2-fold change

Role of endothelium in radiation-induced normal tissue damages; Role de l'endothelium dans les dommages radio-induits aux tissus sains

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Milliat, F

2007-05-15

More than half of cancers are treated with radiation therapy alone or in combination with surgery and/or chemotherapy. The goal of radiation therapy is to deliver enough ionising radiation to destroy cancer cells without exceeding the level that the surrounding healthy cells can tolerate. Unfortunately, radiation-induced normal tissue injury is still a dose limiting factor in the treatment of cancer with radiotherapy. The knowledge of normal tissue radiobiology is needed to determine molecular mechanisms involved in normal tissue pathogenic pathways in order to identify therapeutic targets and develop strategies to prevent and /or reduce side effects of radiation therapy. The endothelium is known to play a critical role in radiation-induced injury. Our work shows that endothelial cells promote vascular smooth muscle cell proliferation, migration and fibro-genic phenotype after irradiation. Moreover, we demonstrate for the first time the importance of PAI-1 in radiation-induced normal tissue damage suggesting that PAI-1 may represent a molecular target to limit injury following radiotherapy. We describe a new role for the TGF-b/Smad pathway in the pathogenesis of radiation-induced damages. TGF-b/Smad pathway is involved in the fibro-genic phenotype of VSMC induced by irradiated EC as well as in the radiation-induced PAI-1 expression in endothelial cells. (author)

Evaluation of ionizing radiation effects in bone tissue by FTIR spectroscopy and dynamic mechanical analysis

International Nuclear Information System (INIS)

Veloso, Marcelo N.; Santin, Stefany P.; Benetti, Carolina; Pereira, Thiago M.; Mattor, Monica B.; Politano, Rodolfo; Zezell, Denise M.

2013-01-01

In many medical practices the bone tissue exposure to ionizing radiation is necessary. However, this radiation can interact with bone tissue in a molecular level, causing chemical and mechanical changes related with the dose used. The aim of this study was verify the changes promoted by different doses of ionizing radiation in bone tissue using spectroscopy technique of Attenuate Total Reflectance - Fourier Transforms Infrared (ATR-FTIR) and dynamic mechanical analysis. Samples of bovine bone were irradiated using irradiator of Cobalt-60 with five different doses between 0.01 kGy, 0.1 kGy,1 kGy, 15 kGy and 75 kGy. To study the effects of ionizing irradiation on bone chemical structure the sub-bands of amide I and the crystallinity index were studied. The mechanical changes were evaluated using the elastic modulus and the damping value. To verify if the chemical changes and the bone mechanic characteristics were related, it was made one study about the correlation between the crystallinity index and the elastic modulus, between the sub-bands ratio and the damping value and between the sub-bands ratio and the elastic modulus. It was possible to evaluate the effects of different dose of ionizing radiation in bone tissue. With ATR-FTIR spectroscopy analysis, it was possible observe changes in the organic components and in the hydroxyapatite crystals organization. Changes were also observed in the mechanical properties. A good correlation between the techniques was found, however, it was not possible to establish a linear or exponential dependence between dose and effect. (author)

Morphology of mucosa-associated lymphoid tissue in odontocetes.

Science.gov (United States)

Silva, Fernanda M O; Guimarães, Juliana P; Vergara-Parente, Jociery E; Carvalho, Vitor L; Carolina, Ana; Meirelles, O; Marmontel, Miriam; Oliveira, Bruno S S P; Santos, Silvanise M; Becegato, Estella Z; Evangelista, Janaina S A M; Miglino, Maria Angelica

2016-09-01

This study describes the mucosa-associated lymphoid tissue (MALT) in odontocetes from the Brazilian coast and freshwater systems. Seven species were evaluated and tissue samples were analyzed by light, scanning and transmission electron microscopy, and immunohistochemistry. Laryngeal tonsil was a palpable oval mass located in the larynx, composed of a lymphoepithelial complex. Dense collections of lymphocytes were found in the skin of male fetus and calf. Clusters of lymphoid tissue were found in the uterine cervix of a reproductively active juvenile female and along the pulmonary artery of an adult female. Lymphoid tissues associated with the gastrointestinal tract were characterized by diffusely arranged or organized lymphocytes. The anal tonsil was composed of an aggregate of lymphoid tissue occurring exclusively in the anal canal, being composed of squamous epithelium branches. MALT was present in different tissues and organic systems of cetaceans, providing constant protection against mucosal pathogens present in their environment. © 2016 Wiley Periodicals, Inc.

Radiation recall dermatitis with soft tissue necrosis following pemetrexed therapy: a case report

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Spirig Christian

2009-11-01

Full Text Available Abstract Introduction Radiation recall dermatitis is a well known but still poorly understood inflammatory reaction. It can develop in previously irradiated areas and has been shown to be triggered by a variety of different drugs, including cytostatic agents. Pemetrexed may cause radiation recall dermatitis in pre-irradiated patients. Case presentation We present the case of a 49-year-old Caucasian woman with non-small cell lung cancer who was initially treated with carboplatin and paclitaxel concomitant with radiotherapy after suffering a painful plexus brachialis infiltration. Due to disease progression, a second-line treatment with pemetrexed was started. A severe soft tissue necrosis developed despite steroid treatment and plastic surgery. Conclusion To the best of our knowledge, we present the first case of a patient with severe soft tissue necrosis in a pre-irradiated area after pemetrexed therapy. We believe that physicians treating patients with pemetrexed should be aware of the severe, possibly life-threatening effects that may be induced by pemetrexed after previous radiation therapy.

Cadmium distribution and selected tissue histology in rats following administration of cadmium chloride and/or gamma radiation

International Nuclear Information System (INIS)

Kundomal, Y.R.

1981-01-01

Sprague-Dawley rats were injected IP with CdCl 2 or distilled water, and/or given a total-body irradiation. Three lethality studies, acute Cd, chronic Cd, and acute radiation, were performed to determine the sublethal doses for the co-insult study. Lethal doses (LD 50 ) were obtained by probit analysis. Cd concentrations were determined by the atomic absorption spectrophotometry. The analysis of variance was used to test the data. LD/sub 50(30)/ values obtained for respective male and female rats were: 5.99 and 7.13 mg/kg of body wt for acute Cd; 4.25 and 5.99 mg/kg of body wt for chronic Cd; and 733 and 729 R for acute radiation. On days 1, 7 and 21 post-irradiation, rats given Cd singly or in combination with radiation showed a high accumulation and retention of metal in the liver and kidney. Then followed in order of decreasing Cd concentrations were: spleen, intestine, stomach, heart, testis, lung, blood cells, brain, and muscle. High Cd concentrations in the liver and kidney persisted over a 21-day observation period; the concentrations in the other tissues decreased, some to control values. Radiation was not an antagonist on Cd concentrations or retentions in these tissues except the heart, in which radiation contributed to the clearance of Cd. Radiation did not act as a synergistic agent on Cd concentrations or retentions in any of the tissues analyzed. Radiation singly had no morphological or physiological effects on the parameters of this study. Based on the high Cd concentrations in these tissues, histological examinations of the liver and kidney sections were made. In the high co-insult groups slight abnormalities, such as pyknotic nuclei in the liver and cellular disorganization and larger lumens in the kidney were observed

Modelling radiation fields of ion beams in tissue-like materials

International Nuclear Information System (INIS)

Burigo, Lucas Norberto

2014-01-01

Fast nuclei are ionizing radiation which can cause deleterious effects to irradiated cells. The modelling of the interactions of such ions with matter and the related effects are very important to physics, radiobiology, medicine and space science and technology. A powerful method to study the interactions of ionizing radiation with biological systems was developed in the field of microdosimetry. Microdosimetry spectra characterize the energy deposition to objects of cellular size, i.e., a few micrometers. In the present thesis the interaction of ions with tissue-like media was investigated using the Monte Carlo model for Heavy-Ion Therapy (MCHIT) developed at the Frankfurt Institute for Advanced Studies. MCHIT is a Geant4-based application intended to benchmark the physical models of Geant4 and investigate the physical properties of therapeutic ion beams. We have implemented new features in MCHIT in order to calculate microdosimetric quantities characterizing the radiation fields of accelerated nucleons and nuclei. The results of our Monte Carlo simulations were compared with recent experimental microdosimetry data. In addition to microdosimetry calculations with MCHIT, we also investigated the biological properties of ion beams, e.g. their relative biological effectiveness (RBE), by means of the modified Microdosimetric-Kinetic model (MKM). The MKM uses microdosimetry spectra in describing cell response to radiation. MCHIT+MKM allowed us to study the physical and biological properties of ion beams. The main results of the thesis are as follows: MCHIT is able to describe the spatial distribution of the physical dose in tissue-like media and microdosimetry spectra for ions with energies relevant to space research and ion-beam cancer therapy; MCHIT+MKM predicts a reduction of the biological effectiveness of ions propagating in extended medium due to nuclear fragmentation reactions; We predicted favourable biological dose-depth profiles for monoenergetic helium and

A case of cardiac cancer diagnosed after 30 Gy radiation therapy for gastric mucosa-associated lymphoid tissue (MALT) lymphoma without helicobacter pylori (H. pylori) infection

International Nuclear Information System (INIS)

Ito, Kazuhiro; Akamatsu, Taiji; Shinji, Akihiro

2005-01-01

An 80-year-old man was referred to Shinshu University Hospital in April 2001 for treatment of gastric mucosa-associated lymphoid tissue (MALT) lymphoma. He had received anti-biotic therapy in spite of no evidence of H. pylori infection in the former hospital 3 years ago, but no remarkable improvement was recognized and endoscopic findings were progressive. An esophagogastroduodenoscopy (EGD) revealed mucosal redness on the greater curvature and the anterior wall of the body. Biopsy specimens taken from the lesions showed remarkable infiltration of atypical small lymphocytes, and this lesions were diagnosed MALT lymphoma by an immunophenotypic studies. Endoscopic ultrasonography (EUS) showed that MALT lymphoma was limited within the mucosa and submucosa. Staging work up revealed stage I. After written informed consent, he was treated by 30 Gy radiation therapy for gastric MALT lymphoma. Response assessment was performed by EGD, EUS, and biopsy specimens, and a complete remission was confirmed. After that, he was followed up with regular intervals, and EGD was performed every 6 months. He was diagnosed to have O I type cardiac cancer at 21 months after radiation therapy. He underwent proximal partial gastrectomy, and histopathological findings showed as follows: O I type, 17 x 12 mm, tub 2, SM, ly 1, v 1, n 0, PM (-), DM (-), INFγ, stage I A. No residual lesion of gastric MALT lymphoma and no dysplasia of gastric mucosa was recognized. Causal relationship between radiation therapy and carcinogenesis in this case is unclear. However, it might be suggested by the facts that cancer occurred in the radiation field where MALT lymphoma had been presented and gastric cancer was rare in the stomach without H. pylori infection. (author)

Study of electron densities of normal and neoplastic human breast tissues by Compton scattering using synchrotron radiation

Energy Technology Data Exchange (ETDEWEB)

Antoniassi, M.; Conceicao, A.L.C. [Departamento de Fisica-Faculdade de Filosofia Ciencias e Letras de Ribeirao Preto-Universidade de Sao Paulo, Ribeirao Preto, Sao Paulo (Brazil); Poletti, M.E., E-mail: poletti@ffclrp.usp.br [Departamento de Fisica-Faculdade de Filosofia Ciencias e Letras de Ribeirao Preto-Universidade de Sao Paulo, Ribeirao Preto, Sao Paulo (Brazil)

2012-07-15

Electron densities of 33 samples of normal (adipose and fibroglangular) and neoplastic (benign and malignant) human breast tissues were determined through Compton scattering data using a monochromatic synchrotron radiation source and an energy dispersive detector. The area of Compton peaks was used to determine the electron densities of the samples. Adipose tissue exhibits the lowest values of electron density whereas malignant tissue the highest. The relationship with their histology was discussed. Comparison with previous results showed differences smaller than 4%. - Highlights: Black-Right-Pointing-Pointer Electron density of normal and neoplastic breast tissues was measured using Compton scattering. Black-Right-Pointing-Pointer Monochromatic synchrotron radiation was used to obtain the Compton scattering data. Black-Right-Pointing-Pointer The area of Compton peaks was used to determine the electron densities of samples. Black-Right-Pointing-Pointer Adipose tissue shows the lowest electron density values whereas the malignant tissue the highest. Black-Right-Pointing-Pointer Comparison with previous results showed differences smaller than 4%.

Study of electron densities of normal and neoplastic human breast tissues by Compton scattering using synchrotron radiation

International Nuclear Information System (INIS)

Antoniassi, M.; Conceição, A.L.C.; Poletti, M.E.

2012-01-01

Electron densities of 33 samples of normal (adipose and fibroglangular) and neoplastic (benign and malignant) human breast tissues were determined through Compton scattering data using a monochromatic synchrotron radiation source and an energy dispersive detector. The area of Compton peaks was used to determine the electron densities of the samples. Adipose tissue exhibits the lowest values of electron density whereas malignant tissue the highest. The relationship with their histology was discussed. Comparison with previous results showed differences smaller than 4%. - Highlights: ► Electron density of normal and neoplastic breast tissues was measured using Compton scattering. ► Monochromatic synchrotron radiation was used to obtain the Compton scattering data. ► The area of Compton peaks was used to determine the electron densities of samples. ► Adipose tissue shows the lowest electron density values whereas the malignant tissue the highest. ► Comparison with previous results showed differences smaller than 4%.

Assessment of illnesses associated with occupational exposure to ionizing radiation

International Nuclear Information System (INIS)

Frometa Suarez, I.

1996-01-01

The medical surveillance of occupationally exposed workers allows to assess their health condition and is supported by the performance of pre-employment and periodic medical researches that would lead to the discovery of deviations or disorders in organs and tissues specially sensitive to radiation damage as a result of working with ionizing radiation

Normal tissue complication probability modeling of radiation-induced hypothyroidism after head-and-neck radiation therapy.

Science.gov (United States)

Bakhshandeh, Mohsen; Hashemi, Bijan; Mahdavi, Seied Rabi Mehdi; Nikoofar, Alireza; Vasheghani, Maryam; Kazemnejad, Anoshirvan

2013-02-01

To determine the dose-response relationship of the thyroid for radiation-induced hypothyroidism in head-and-neck radiation therapy, according to 6 normal tissue complication probability models, and to find the best-fit parameters of the models. Sixty-five patients treated with primary or postoperative radiation therapy for various cancers in the head-and-neck region were prospectively evaluated. Patient serum samples (tri-iodothyronine, thyroxine, thyroid-stimulating hormone [TSH], free tri-iodothyronine, and free thyroxine) were measured before and at regular time intervals until 1 year after the completion of radiation therapy. Dose-volume histograms (DVHs) of the patients' thyroid gland were derived from their computed tomography (CT)-based treatment planning data. Hypothyroidism was defined as increased TSH (subclinical hypothyroidism) or increased TSH in combination with decreased free thyroxine and thyroxine (clinical hypothyroidism). Thyroid DVHs were converted to 2 Gy/fraction equivalent doses using the linear-quadratic formula with α/β = 3 Gy. The evaluated models included the following: Lyman with the DVH reduced to the equivalent uniform dose (EUD), known as LEUD; Logit-EUD; mean dose; relative seriality; individual critical volume; and population critical volume models. The parameters of the models were obtained by fitting the patients' data using a maximum likelihood analysis method. The goodness of fit of the models was determined by the 2-sample Kolmogorov-Smirnov test. Ranking of the models was made according to Akaike's information criterion. Twenty-nine patients (44.6%) experienced hypothyroidism. None of the models was rejected according to the evaluation of the goodness of fit. The mean dose model was ranked as the best model on the basis of its Akaike's information criterion value. The D(50) estimated from the models was approximately 44 Gy. The implemented normal tissue complication probability models showed a parallel architecture for the

Normal Tissue Complication Probability Modeling of Radiation-Induced Hypothyroidism After Head-and-Neck Radiation Therapy

Energy Technology Data Exchange (ETDEWEB)

Bakhshandeh, Mohsen [Department of Medical Physics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran (Iran, Islamic Republic of); Hashemi, Bijan, E-mail: bhashemi@modares.ac.ir [Department of Medical Physics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran (Iran, Islamic Republic of); Mahdavi, Seied Rabi Mehdi [Department of Medical Physics, Faculty of Medical Sciences, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Nikoofar, Alireza; Vasheghani, Maryam [Department of Radiation Oncology, Hafte-Tir Hospital, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Kazemnejad, Anoshirvan [Department of Biostatistics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran (Iran, Islamic Republic of)

2013-02-01

Purpose: To determine the dose-response relationship of the thyroid for radiation-induced hypothyroidism in head-and-neck radiation therapy, according to 6 normal tissue complication probability models, and to find the best-fit parameters of the models. Methods and Materials: Sixty-five patients treated with primary or postoperative radiation therapy for various cancers in the head-and-neck region were prospectively evaluated. Patient serum samples (tri-iodothyronine, thyroxine, thyroid-stimulating hormone [TSH], free tri-iodothyronine, and free thyroxine) were measured before and at regular time intervals until 1 year after the completion of radiation therapy. Dose-volume histograms (DVHs) of the patients' thyroid gland were derived from their computed tomography (CT)-based treatment planning data. Hypothyroidism was defined as increased TSH (subclinical hypothyroidism) or increased TSH in combination with decreased free thyroxine and thyroxine (clinical hypothyroidism). Thyroid DVHs were converted to 2 Gy/fraction equivalent doses using the linear-quadratic formula with {alpha}/{beta} = 3 Gy. The evaluated models included the following: Lyman with the DVH reduced to the equivalent uniform dose (EUD), known as LEUD; Logit-EUD; mean dose; relative seriality; individual critical volume; and population critical volume models. The parameters of the models were obtained by fitting the patients' data using a maximum likelihood analysis method. The goodness of fit of the models was determined by the 2-sample Kolmogorov-Smirnov test. Ranking of the models was made according to Akaike's information criterion. Results: Twenty-nine patients (44.6%) experienced hypothyroidism. None of the models was rejected according to the evaluation of the goodness of fit. The mean dose model was ranked as the best model on the basis of its Akaike's information criterion value. The D{sub 50} estimated from the models was approximately 44 Gy. Conclusions: The implemented

Necrose adiposa do recém-nascido: a propósito de dois casos clínicos Fat necrosis of the newborn: report on two cases

Directory of Open Access Journals (Sweden)

Ana Cristina Santos Oliveira

2011-08-01

Full Text Available A necrose adiposa subcutânea do recém-nascido é uma paniculite rara do período neonatal. Surge, geralmente, em recém-nascidos de termo ou pós-termo, nas primeiras 4 semanas de vida, e em associação com trauma obstétrico. Caracteriza-se pelo aparecimento de placas ou nódulos subcutâneos duros, localizados ao tronco, nádegas ou coxas. O seu curso é, geralmente, benigno e autolimitado, embora possa acompanhar-se de hipercalcemia, o que obriga a uma vigilância periódica até à resolução das lesões cutâneas. Os autores descrevem 2 casos de necrose adiposa subcutânea do recém-nascido, um num recémnascido de termo, outro num prematuro, ambos associados a partos traumáticos e a sofrimento fetalSubcutaneous fat necrosis of the newborn is an uncommon disorder occurring during the prenatal stage. Generally occurring in full-term neonates or during the first four weeks after a traumatic delivery, the disorder is characterized by the appearance of hard subcutaneous nodules or plaques on the trunk, buttocks or thighs. It is normally a benign and transient condition, although it may be complicated by hypocalcemia, which requires close monitoring until skin lesions are cured. The authors describe two cases of subcutaneous fat necrosis of the newborn, one occurring in a full-term neonate and the other in a premature newborn, both related to traumatic delivery and fetal distress

Tissue banking, biovigilance and the notify library.

Science.gov (United States)

Strong, D Michael

2017-06-30

This issue is dedicated to the contributions of Professor Glyn O. Phillips to the field of tissue banking and the advancement of science in general. The use of ionizing radiation to sterilize medical products drew the interest of the International Atomic Energy Agency (IAEA). A meeting in 1976 in Athens Greece to present work on the effects of sterilizing radiation doses upon the antigenic properties of proteins and biologic tissues was my first introduction of Professor Phillips and the role that he was to play in Tissue Banking (Friedlaender, in Phillips GO, Tallentine AN (eds) Radiation sterilization. Irradiated tissues and their potential clinical use. The North E. Wales Institute, Clwyd, p 128, 1978). The IAEA sponsored subsequent meetings in the Republic of Korea, Czechoslovakia and Rangoon, the later including a visit to the tissue bank by Professor Phillips. His advocacy resulted in multiple workshops and teaching opportunities in a variety of countries, one of which led to the establishment of the Asia Pacific Surgical Tissue Banking Association in 1989 (Phillips and Strong, in Phillips GO, Strong DM, von Versen R, Nather A (eds) Advances in tissue banking, vol 3. World Scientific, Singapore, pp 403-417, 1999).

Effect of Brain Tumor Presence During Radiation on Tissue Toxicity: Transcriptomic and Metabolic Changes.

Science.gov (United States)

Zawaski, Janice A; Sabek, Omaima M; Voicu, Horatiu; Eastwood Leung, Hon-Chiu; Gaber, M Waleed

2017-11-15

Radiation therapy (RT) causes functional and transcriptomic changes in the brain; however, most studies have been carried out in normal rodent brains. Here, the long-term effect of irradiation and tumor presence during radiation was investigated. Male Wistar rats ∼7 weeks old were divided into 3 groups: sham implant, RT+sham implant, and RT+tumor implant (C6 glioma). Hypofractionated irradiation (8 or 6 Gy/day for 5 days) was localized to a 1-cm strip of cranium starting 5 days after implantation, resulting in complete tumor regression and prolonged survival. Biopsy of tissue was performed in the implant area 65 days after implantation. RNA was hybridized to GeneChip Rat Exon 1.0 ST array. Data were analyzed using significant analysis of microarrays and ingenuity pathway analysis. 1 H magnetic resonance spectroscopy ( 1 H-MRS) imaging was performed in the implantation site 65 to 70 days after implantation using a 9.4 T Biospec magnetic resonance imaging scanner with a quadrature rat brain array. Immunohistochemical staining for astrogliosis, HMG-CoA synthase 2, γ-aminobutyric acid (GABA) and taurine was performed at ∼65 days after implantation. Eighty-four genes had a false discovery rate <3.5%. We compared RT+tumor implant with RT+sham implant animals. The tumor presence affected networks associated with cancer/cell morphology/tissue morphology. 1 H-MRS showed significant reduction in taurine levels (P<.04) at the implantation site in both groups. However, the RT+tumor group also showed significant increase in levels of neurotransmitter GABA (P=.02). Hippocampal taurine levels were only significantly reduced in the RT+tumor group (P=.03). HMG-CoA synthase 2, GABA and taurine levels were confirmed using staining. Glial fibrillary acidic protein staining demonstrated a significant increase in inflammation that was heightened in the RT+tumor group. Our data indicate that tumor presence during radiation significantly affects long-term functional

Toward in vivo lung's tissue incompressibility characterization for tumor motion modeling in radiation therapy

International Nuclear Information System (INIS)

Shirzadi, Zahra; Sadeghi-Naini, Ali; Samani, Abbas

2013-01-01

Purpose: A novel technique is proposed to characterize lung tissue incompressibility variation during respiration. Estimating lung tissue incompressibility parameter variations resulting from air content variation throughout respiration is critical for computer assisted tumor motion tracking. Continuous tumor motion is a major challenge in lung cancer radiotherapy, especially with external beam radiotherapy. If not accounted for, this motion may lead to areas of radiation overdosage for normal tissue. Given the unavailability of imaging modality that can be used effectively for real-time lung tumor tracking, computer assisted approach based on tissue deformation estimation can be a good alternative. This approach involves lung biomechanical model where its fidelity depends on input tissue properties. This investigation shows that considering variable tissue incompressibility parameter is very important for predicting tumor motion accurately, hence improving the lung radiotherapy outcome. Methods: First, an in silico lung phantom study was conducted to demonstrate the importance of employing variable Poisson's ratio for tumor motion predication. After it was established that modeling this variability is critical for accurate tumor motion prediction, an optimization based technique was developed to estimate lung tissue Poisson's ratio as a function of respiration cycle time. In this technique, the Poisson's ratio and lung pressure value were varied systematically until optimal values were obtained, leading to maximum similarity between acquired and simulated 4D CT lung images. This technique was applied in an ex vivo porcine lung study where simulated images were constructed using the end exhale CT image and deformation fields obtained from the lung's FE modeling of each respiration time increment. To model the tissue, linear elastic and Marlow hyperelastic material models in conjunction with variable Poisson's ratio were used. Results: The phantom study showed that

Tolerance doses of cutaneous and mucosal tissues in ring-necked parakeets (Psittacula krameri) for external beam megavoltage radiation.

Science.gov (United States)

Barron, Heather W; Roberts, Royce E; Latimer, Kenneth S; Hernandez-Divers, Stephen; Northrup, Nicole C

2009-03-01

Currently used dosages for external-beam megavoltage radiation therapy in birds have been extrapolated from mammalian patients and often appear to provide inadequate doses of radiation for effective tumor control. To determine the tolerance doses of cutaneous and mucosal tissues of normal birds in order to provide more effective radiation treatment for tumors that have been shown to be radiation responsive in other species, ingluvial mucosa and the skin over the ingluvies of 9 ring-necked parakeets (Psittacula krameri) were irradiated in 4-Gy fractions to a total dose of either 48, 60, or 72 Gy using an isocentric cobalt-60 teletherapy unit. Minimal radiation-induced epidermal changes were present in the high-dose group histologically. Neither dose-related acute nor chronic radiation effects could be detected in any group grossly in cutaneous or mucosal tissue over a 9-month period. Radiation doses of 72 Gy in 4-Gy fractions were well tolerated in the small number of ring-necked parakeets in this initial tolerance dose study.

The impact of the International Atomic Energy Agency (IAEA) program on radiation and tissue banking in Peru.

Science.gov (United States)

Gamero, Emma Castro; Morales Pedraza, Jorge

2009-05-01

The tissue bank "Rosa Guerzoni Chambergo" (RGCTB) located at the Child's Health Institute was inaugurated in 1996, with the financial and technical support of the IAEA program on radiation and tissue banking. Since 1998, the biological bandage of fresh and lyophilised pigskin, amnion and bone tissue is processed routinely in this bank. In all cases, the tissue is sterilised with the use of Cobalt-60 radiation, process carried out at the Laboratories of Irradiation of the Peruvian Institute of Nuclear Energy (IPEN). The tissue bank in the Child's Health Institute helped to save lives in an accident occurred in Lima, when a New Year's fireworks celebration ran out of control in January 2002. Nearly 300 people died in the tragic blaze and hundreds more were seriously burned and injured. Eight Lima hospitals and clinics suddenly were faced with saving the lives of severely burned men, women and children. Fortunately, authorities were ready to respond to the emergency. More than 1,600 dressings were sterilised and supplied to Lima surgeons. The efforts helped save the lives of patients who otherwise might not have survived the Lima fire. Between 1998 and September 2007, 35,012 tissue grafts were produced and irradiated. Radiation sterilised tissues are used by 20 national medical institutions as well as 17 private health institutions. The tissue bank established in Peru with the support of the IAEA is now producing the following tissues: pigskin dressings, fresh and freeze-dried; bone allografts, chips, wedges and powdered, and amnion dressings air-dried. It is also now leading the elaboration of national standards, assignment being entrusted by ONDT (Organización Nacional de Donación y Transplantes; National Organisation on Donation and Transplant). This among other will permit the accreditation of the tissue bank. In this task is also participating IPEN.

Vasculatures in Tumors Growing From Preirradiated Tissues: Formed by Vasculogenesis and Resistant to Radiation and Antiangiogenic Therapy

International Nuclear Information System (INIS)

Chen, Fang-Hsin; Chiang, Chi-Shiun; Wang, Chun-Chieh; Fu, Sheng-Yung; Tsai, Chien-Sheng; Jung, Shih-Ming; Wen, Chih-Jen; Lee, Chung-Chi; Hong, Ji-Hong

2011-01-01

Purpose: To investigate vasculatures and microenvironment in tumors growing from preirradiated tissues (pre-IR tumors) and study the vascular responses of pre-IR tumors to radiation and antiangiogenic therapy. Methods and Materials: Transgenic adenocarcinoma of the mouse prostate C1 tumors were implanted into unirradiated or preirradiated tissues and examined for vascularity, hypoxia, and tumor-associated macrophage (TAM) infiltrates by immunohistochemistry. The origin of tumor endothelial cells was studied by green fluorescent protein-tagged bone marrow (GFP-BM) transplantation. The response of tumor endothelial cells to radiation and antiangiogenic agent was evaluated by apoptotic assay. Results: The pre-IR tumors had obvious tumor bed effects (TBE), with slower growth rate, lower microvascular density (MVD), and more necrotic and hypoxic fraction compared with control tumors. The vessels were dilated, tightly adhered with pericytes, and incorporated with transplanted GFP-BM cells. In addition, hypoxic regions became aggregated with TAM. As pre-IR tumors developed, the TBE was overcome at the tumor edge where the MVD increased, TAM did not aggregate, and the GFP-BM cells did not incorporate into the vessels. The vessels at tumor edge were more sensitive to the following ionizing radiation and antiangiogenic agent than those in the central low MVD regions. Conclusions: This study demonstrates that vasculatures in regions with TBE are mainly formed by vasculogenesis and resistant to radiation and antiangiogenic therapy. Tumor bed effects could be overcome at the edge of larger tumors, but where vasculatures are formed by angiogenesis and sensitive to both treatments. Vasculatures formed by vasculogenesis should be the crucial target for the treatment of recurrent tumors after radiotherapy.

Radiation therapy for gastric mucosa-associated lymphoid tissue lymphoma: Dose-volumetric analysis and its clinical implications

International Nuclear Information System (INIS)

Lim, Hyeon Won; Kim, Tae Hyun; Choi, Il Ju; Kim, Chan Gyoo; Lee, Jong Yeul; Cho, Soo Jeong; Eom, Hyeon Seok; Moon, Sung Ho; Kim, Dae Yong

2016-01-01

To assess the clinical outcomes of radiotherapy (RT) using two-dimensional (2D) and three-dimensional conformal RT (3D-CRT) for patients with gastric mucosa-associated lymphoid tissue (MALT) lymphoma to evaluate the effectiveness of involved field RT with moderate-dose and to evaluate the benefit of 3D-CRT comparing with 2D-RT. Between July 2003 and March 2015, 33 patients with stage IE and IIE gastric MALT lymphoma received RT were analyzed. Of 33 patients, 17 patients (51.5%) were Helicobacter pylori (HP) negative and 16 patients (48.5%) were HP positive but refractory to HP eradication (HPE). The 2D-RT (n = 14) and 3D-CRT (n = 19) were performed and total dose was 30.6 Gy/17 fractions. Of 11 patients who RT planning data were available, dose-volumetric parameters between 2D-RT and 3D-CRT plans was compared. All patients reached complete remission (CR) eventually and median time to CR was 3 months (range, 1 to 15 months). No local relapse occurred and one patient died with second primary malignancy. Tumor response, survival, and toxicity were not significantly different between 2D-RT and 3D-CRT (p > 0.05, each). In analysis for dose-volumetric parameters, Dmax and CI for PTV were significantly lower in 3D-CRT plans than 2D-RT plans (p < 0.05, each) and Dmean and V15 for right kidney and Dmean for left kidney were significantly lower in 3D-CRT than 2D-RT (p < 0.05, each). Our data suggested that involved field RT with moderate-dose for gastric MALT lymphoma could be promising and 3D-CRT could be considered to improve the target coverage and reduce radiation dose to the both kidneys

Radiation therapy for gastric mucosa-associated lymphoid tissue lymphoma: Dose-volumetric analysis and its clinical implications

Energy Technology Data Exchange (ETDEWEB)

Lim, Hyeon Won; Kim, Tae Hyun; Choi, Il Ju; Kim, Chan Gyoo; Lee, Jong Yeul; Cho, Soo Jeong; Eom, Hyeon Seok; Moon, Sung Ho; Kim, Dae Yong [Research Institute and Hospital, National Cancer Center, Goyang (Korea, Republic of)

2016-09-15

To assess the clinical outcomes of radiotherapy (RT) using two-dimensional (2D) and three-dimensional conformal RT (3D-CRT) for patients with gastric mucosa-associated lymphoid tissue (MALT) lymphoma to evaluate the effectiveness of involved field RT with moderate-dose and to evaluate the benefit of 3D-CRT comparing with 2D-RT. Between July 2003 and March 2015, 33 patients with stage IE and IIE gastric MALT lymphoma received RT were analyzed. Of 33 patients, 17 patients (51.5%) were Helicobacter pylori (HP) negative and 16 patients (48.5%) were HP positive but refractory to HP eradication (HPE). The 2D-RT (n = 14) and 3D-CRT (n = 19) were performed and total dose was 30.6 Gy/17 fractions. Of 11 patients who RT planning data were available, dose-volumetric parameters between 2D-RT and 3D-CRT plans was compared. All patients reached complete remission (CR) eventually and median time to CR was 3 months (range, 1 to 15 months). No local relapse occurred and one patient died with second primary malignancy. Tumor response, survival, and toxicity were not significantly different between 2D-RT and 3D-CRT (p > 0.05, each). In analysis for dose-volumetric parameters, Dmax and CI for PTV were significantly lower in 3D-CRT plans than 2D-RT plans (p < 0.05, each) and Dmean and V15 for right kidney and Dmean for left kidney were significantly lower in 3D-CRT than 2D-RT (p < 0.05, each). Our data suggested that involved field RT with moderate-dose for gastric MALT lymphoma could be promising and 3D-CRT could be considered to improve the target coverage and reduce radiation dose to the both kidneys.

Alternativas de medicação intracanal em casos de necrose pulpar com lesão periapical = Intracanal medication indicated for pulpal necrosis with apical osteites

OpenAIRE

Fachin, Elaine Vianna Freitas

2006-01-01

Trata-se de estudo in vivo em pacientes portadores de dentes monorradiculares apresentando necrose pulpar com lesão periapical. O objetivo foi avaliar radiograficamente a efetividade de 4 diferentes curativos de demora (PMCC, gel de clorexidina 2%, pasta de hidróxido de cálcio e hipoclorito de sódio1%). O tratamento endodôntico foi padronizado em todos os elementos através da técnica escalonada e irrigação com hipoclorito de sódio 1%. Para a medicação intracanal, os pacientes foram separados ...

Role of endothelium in radiation-induced normal tissue damages; Role de l'endothelium dans les dommages radio-induits aux tissus sains

Energy Technology Data Exchange (ETDEWEB)

Milliat, F

2007-05-15

More than half of cancers are treated with radiation therapy alone or in combination with surgery and/or chemotherapy. The goal of radiation therapy is to deliver enough ionising radiation to destroy cancer cells without exceeding the level that the surrounding healthy cells can tolerate. Unfortunately, radiation-induced normal tissue injury is still a dose limiting factor in the treatment of cancer with radiotherapy. The knowledge of normal tissue radiobiology is needed to determine molecular mechanisms involved in normal tissue pathogenic pathways in order to identify therapeutic targets and develop strategies to prevent and /or reduce side effects of radiation therapy. The endothelium is known to play a critical role in radiation-induced injury. Our work shows that endothelial cells promote vascular smooth muscle cell proliferation, migration and fibro-genic phenotype after irradiation. Moreover, we demonstrate for the first time the importance of PAI-1 in radiation-induced normal tissue damage suggesting that PAI-1 may represent a molecular target to limit injury following radiotherapy. We describe a new role for the TGF-b/Smad pathway in the pathogenesis of radiation-induced damages. TGF-b/Smad pathway is involved in the fibro-genic phenotype of VSMC induced by irradiated EC as well as in the radiation-induced PAI-1 expression in endothelial cells. (author)

Prótese do tornozelo híbrida em um caso de necrose avascular pós-traumática do tálus Hybrid ankle prosthesis in a case of post-traumatic avascular necrosis of the talus

Directory of Open Access Journals (Sweden)

Ricardo Jorge Gomes de Sousa

2011-01-01

Full Text Available As fraturas do astrágalo originam frequentemente artrose pós-traumática tardia. Nestes casos, a utilização de próteses do tornozelo não cimentadas de última geração tem sido evitada pela presença de necrose avascular. Relatamos o caso de um paciente com 65 anos que se apresenta quatro anos após uma fratura do colo do astrágalo. Apresentava uma artrose do tornozelo dolorosa (escala AOFAS do retropé e tornozelo 19 e necrose avascular com colapso de toda a cúpula astragalina. Dada a extensão da necrose, foi decidido cimentar o componente protésico astragalino. Um ano após a cirurgia, o paciente apresenta bom resultado clínico e radiológico (escala AOFAS do retropé e tornozelo 87 e está satisfeito com o procedimento. Não temos conhecimento de nenhum relato semelhante na literatura.Talus fractures often lead to late post-traumatic arthrosis. In such cases, the use of latest generation, cementless prostheses has been hindered by the presence of avascular necrosis. We report the case of a 65-year-old patient who presented four years after a talus neck fracture. He had painful ankle arthrosis (AOFAS ankle-hindfoot score 19 and avascular necrosis, with collapse of the entire talar dome. Given the extent of the necrosis, it was decided to cement the talus prosthetic component. One year after the surgery, the patient shows good clinical and radiological results (AOFAS ankle-hindfoot score 87 and is satisfied with the procedure. We are not aware of any similar reports in the literature.

Role of plasminogen activator inhibitor type-1 in radiation-induced normal tissues injury

International Nuclear Information System (INIS)

Abderrahmani, R.

2010-01-01

Radiotherapy is an essential tool for cancer treatment, but there is a balance between benefits and risks related to the use of ionizing radiation: the objective is to deliver a maximum dose to the tumour to destroy or to sterilize it while protecting surrounding normal tissues. Radio-induced damages to normal tissues are therefore a limiting factor when increasing the dose delivered to the tumour. One of the objectives of this research thesis is to bring to the fore a relationship between the initiation of lesions and the development of late damages, more particularly in the intestine, and to identify the involved molecular actors and their inter-connectivity. After a first part presenting ionizing radiation, describing biological effects of ionizing radiation and their use in radiotherapy, presenting the intestine and the endothelium and discussing the intestine radio-sensitivity, discussing the radio-induced intestine damages and radiotherapy-induced complications, and presenting the plasminogen activator inhibitor (PAI-1) and its behaviour in presence of ionizing radiation, two articles are reproduced. The first one addresses the effect of a pharmacological inhibition and of genetic deficiency in PAI-1 on the evolution of radio-induced intestine lesions. The second one discusses the fact that radio-induced PAI-1-related death of endothelial cells determines the severity of early radio-induced intestine lesions

Leaf hairs of Olea europaea protect underlying tissues against ultraviolet-B radiation damage

International Nuclear Information System (INIS)

Karabourniotis, G.; Kyparissis, A.; Manetas, Y.

1993-01-01

The photochemical efficiency of photosystem II, as measured by chlorophyll fluorescence induction, was not affected in de-haired olive leaves kept in the dark or intact leaves irradiated with a moderate (3.75 W m-2) ultraviolet-B (UV-B) intensity. In de-haired, UV-B-irradiated leaves, however, the ratio of variable to maximum (F(v)/F(m)) chlorophyll fluorescence declined significantly and irreversibly. Reduction in F(v)/V(m) was associated with an increase in instantaneous and a decrease in maximum (F(m)) fluorescence, indicating perturbation by the UV-B exposure of more than one photosynthetic site. Extensive epidermal browning in de-haired, UV-B irradiated leaves was also observed, indicating possible damage to cell membranes. The results strengthen the hypothesis that leaf hairs protect the underlying tissues against UV-B radiation damage

Greetings from Austrian Radiation Protection Association

International Nuclear Information System (INIS)

Hajek, M.; Brandl, A.

2015-01-01

Austrian Radiation Protection Association (OVS) share with others a long-standing tradition of common endeavours and close collaboration. We have been and are able to influence the European radiation protection environment and IRPA initiatives and policies. We are intrigued by the breadth and comprehensive nature of the symposium programme, covering the most important sub-fields in our profession, and spanning topics from radiation dosimetry to radiobiology, from instrumentation and measurement to radioecology, and from radiation protection for workers and in medicine to our professional responsibilities towards the general public. These topics are timeless and current, providing testimony to the fact that the science of radiation protection is not exhausted. Novel applications of ionizing and non-ionizing radiation, including new modalities in the fields of medical therapy and diagnosis, a resurgence of nuclear energy generation in some parts of the globe, combined with increased efforts for decontamination and decommissioning of existing sites and facilities, they are all attest to the continued need for further research and our professional input and discussion. The national radiation protection associations will have a role to play in both, the advocacy of increased efforts to educate and train our future professionals and the retention of those professionals in our field.

Ipsilateral testicular necrosis and atrophy after 1,080-degree torsion of the spermatic cord in rats Necrose e atrofia do testículo ipsilateral após torção de 1080 graus do cordão espermático em ratos

Directory of Open Access Journals (Sweden)

Frederico Ramalho Romero

2009-04-01

Full Text Available PURPOSE: To assess the incidence of testicular necrosis/atrophy immediately after 1 to 4 hours of 1,080-degree torsion of the spermatic cord, and 60 days after detorsion of the spermatic cord. METHODS: 42 rats were divided in 7 groups. Except for the control group, surgical torsion of the right spermatic cord was performed in all groups (T0. After 1, 2, or 4 hours of torsion, each group underwent either ipsilateral orchiectomy (groups OT1, OT2, and OT4, or detorsion of the spermatic cord and observation for 60 days (groups DT1, DT2, and DT4, before they were evaluated for the presence of testicular necrosis/atrophy. RESULTS: Only one rat (5.5% in groups OT1, OT2, and OT4 had testicular necrosis, in comparison with six rats (33.3% in groups DT1, DT2, and DT4 (p=0.04. The incidence of testicular necrosis/atrophy was not different between subgroups T1, T2, and T4, and the control group (p>0.05. There was, however, a tendency toward greater incidence of necrosis/atrophy in the rats in group DT4. CONCLUSION: The incidence of testicular necrosis/atrophy immediately after 1 to 4 hours of 1,080-degree torsion of the spermatic cord is 5.5%, in comparison with 33.3% sixty days after detorsion of the spermatic cord.OBJETIVO: Avaliar a incidência de necrose/atrofia testicular imediatamente após 1 a 4 horas de torção de 1080 graus do cordão espermático e 60 dias após a destorção do cordão espermático. MÉTODOS: 42 ratos foram separados em 7 grupos. Exceto para o grupo controle, todos os animais foram submetidos à torção operatória do cordão espermático direito (T0. Após 1, 2 ou 4 horas de torção, cada grupo foi submetido a orquiectomia ipsilateral (grupos OT1, OT2 e OT4, ou destorção do cordão espermático e observação por 60 dias (grupos DT1, DT2 e DT4, antes de serem avaliados para a presença de necrose/atrofia testicular. RESULTADOS: Somente um rato (5,5% nos grupos OT1, OT2 e OT4 apresentou necrose testicular em comparação com

Enhancing the radiation response of tumors but not early or late responding normal tissues using a vascular disrupting agent

DEFF Research Database (Denmark)

Horsman, Michael R

2017-01-01

INTRODUCTION: Vascular disrupting agents (VDAs) damage tumor vasculature and enhance tumor radiation response. In this pre-clinical study, we combined radiation with the leading VDA in clinical development, combretastatin A-4 phosphate (CA4P), and compared the effects seen in tumors and relevant...... normal tissues. MATERIAL AND METHODS: Radiation was applied locally to tissues in CDF1 mice to produce full radiation dose-response curves. CA4P (250 mg/kg) was intraperitoneally (i.p.) injected within 30 minutes after irradiating. Response of 200 mm3 foot implanted C3H mammary carcinomas was assessed......% increase in ventilation rate measured by plethysmography within 9 months). A Chi-squared test was used for statistical comparisons (significance level of p 4P. The radiation...

The role of adipose tissue in cancer-associated cachexia.

Science.gov (United States)

Vaitkus, Janina A; Celi, Francesco S

2017-03-01

Adipose tissue (fat) is a heterogeneous organ, both in function and histology, distributed throughout the body. White adipose tissue, responsible for energy storage and more recently found to have endocrine and inflammation-modulatory activities, was historically thought to be the only type of fat present in adult humans. The recent demonstration of functional brown adipose tissue in adults, which is highly metabolic, shifted this paradigm. Additionally, recent studies demonstrate the ability of white adipose tissue to be induced toward the brown adipose phenotype - "beige" or "brite" adipose tissue - in a process referred to as "browning." While these adipose tissue depots are under investigation in the context of obesity, new evidence suggests a maladaptive role in other metabolic disturbances including cancer-associated cachexia, which is the topic of this review. This syndrome is multifactorial in nature and is an independent factor associated with poor prognosis. Here, we review the contributions of all three adipose depots - white, brown, and beige - to the development and progression of cancer-associated cachexia. Specifically, we focus on the local and systemic processes involving these adipose tissues that lead to increased energy expenditure and sustained negative energy balance. We highlight key findings from both animal and human studies and discuss areas within the field that need further exploration. Impact statement Cancer-associated cachexia (CAC) is a complex, multifactorial syndrome that negatively impacts patient quality of live and prognosis. This work reviews a component of CAC that lacks prior discussion: adipose tissue contributions. Uniquely, it discusses all three types of adipose tissue, white, beige, and brown, their interactions, and their contributions to the development and progression of CAC. Summarizing key bench and clinical studies, it provides information that will be useful to both basic and clinical researchers in designing

Strategies for Discovery of Small Molecule Radiation Protectors and Radiation Mitigators

Energy Technology Data Exchange (ETDEWEB)

Greenberger, Joel S.; Clump, David [Radiation Oncology Department, University of Pittsburgh Cancer Institute, Pittsburgh, PA (United States); Kagan, Valerian [Environmental and Occupational Health Department, University of Pittsburgh, Pittsburgh, PA (United States); Bayir, Hülya [Critical Care Medicine Department, University of Pittsburgh Medical Center, Pittsburgh, PA (United States); Lazo, John S. [Pharmacology Department, University of Virginia, Charlottesville, VA (United States); Wipf, Peter [Department of Chemistry, Accelerated Chemical Discovery Center, University of Pittsburgh, Pittsburgh, PA (United States); Li, Song; Gao, Xiang [Pharmaceutical Science Department, University of Pittsburgh, Pittsburgh, PA (United States); Epperly, Michael W., E-mail: greenbergerjs@upmc.edu [Radiation Oncology Department, University of Pittsburgh Cancer Institute, Pittsburgh, PA (United States)

2012-01-13

Mitochondrial targeted radiation damage protectors (delivered prior to irradiation) and mitigators (delivered after irradiation, but before the appearance of symptoms associated with radiation syndrome) have been a recent focus in drug discovery for (1) normal tissue radiation protection during fractionated radiotherapy, and (2) radiation terrorism counter measures. Several categories of such molecules have been discovered: nitroxide-linked hybrid molecules, including GS-nitroxide, GS-nitric oxide synthase inhibitors, p53/mdm2/mdm4 inhibitors, and pharmaceutical agents including inhibitors of the phosphoinositide-3-kinase pathway and the anti-seizure medicine, carbamazepine. Evaluation of potential new radiation dose modifying molecules to protect normal tissue includes: clonogenic radiation survival curves, assays for apoptosis and DNA repair, and irradiation-induced depletion of antioxidant stores. Studies of organ specific radioprotection and in total body irradiation-induced hematopoietic syndrome in the mouse model for protection/mitigation facilitate rational means by which to move candidate small molecule drugs along the drug discovery pipeline into clinical development.

Biochemical and morphological changes in rat lung tissue under the influence of external ionizing radiation

International Nuclear Information System (INIS)

Uzlenkova, N.Je.; Mamotyuk, Je.M.; Gusakova, V.A.; Kononenko, O.K.

2006-01-01

Single external x-ray exposure at minimum and mean lethal doses was established to cause a long activation of biochemical processes in the connective tissue of the rat lungs. Morphological and ultrastructure changes in the tissue of the lungs at early terms after x-ray and gamma-radiation exposure were due to development of destructive and degenerative reactions. The long-term changes were characterized by growth of connective tissue and formation of areas of fibrous changes in the structure of the lungs

Variation in normal and tumor tissue sensitivity of mice to ionizing radiation-induced DNA strand breaks in vivo

International Nuclear Information System (INIS)

Meyn, R.E.; Jenkins, W.T.

1983-01-01

The efficiency of DNA strand break formation in normal and tumor tissues of mice was measured using the technique of alkaline elution coupled with a microfluorometric determination of DNA. This methodology allowed measurement of the DNA strand breaks produced in tissues irradiated in vivo with doses of radiation comparable to those used in radiotherapy (i.e., 1.0 gray) without the necessity for the cells to be dividing and incorporating radioactive precursors to label the DNA. The results showed that substantial differences existed among various tissues in terms of the amount of DNA strand break damage produced for a given dose of radiation. Of the normal tissues, the most breaks were produced in bone marrow and the least were produced in gut. Furthermore, strand break production was relatively inefficient in the tumor compared to the normal tissues. The efficiency of DNA strand break formation measured in the cells from the tissues irradiated in vitro was much more uniform and considerably greater than that measured in vivo, suggesting that the normal tissues in the animal may be radiobiologically hypoxic

Effect of laser UV radiation on the eye scleral tissue in patients with open-angle glaucoma

Science.gov (United States)

Razhev, A. M.; Iskakov, I. A.; Churkin, D. S.; Orishich, A. M.; Maslov, N. A.; Tsibul'skaya, E. O.; Lomzov, A. A.; Ermakova, O. V.; Trunov, A. N.; Chernykh, V. V.

2018-05-01

We report the results of an experimental study of the effect of short-pulse laser UV radiation on the eye scleral tissue. As samples, we used isolated flaps of the eye scleral tissue from the patients with open-angle glaucoma of the second and third stages. The impact was implemented using the radiation of an excimer XeCl laser with a wavelength of 308 nm and a laser with a wavelength tunable within from 210 to 355 nm. Depending on the problem to be solved, the energy density on the surface of the irradiated tissue varied from a fraction of mJ cm-2 to 15 J cm-2. For the first time we studied the optical properties of the intraocular fluid in the UV and blue spectral range. The study of the ablation process under the action of radiation with a wavelength of 308 nm showed that the rate of material evaporation can vary within 24%–30% at an energy density above 7 J cm-2, depending on the glaucoma stage and the individual features of a patient. The excitation–emission matrices of laser-induced fluorescence (LIF) of the eye scleral tissue were studied experimentally using a laser with a wavelength tuned in the range 210–355 nm. We found the differences in the LIF spectra caused by the excitation wavelength and the openangle glaucoma stage.

About tendon tissue regeneration in experimental radiation disease

Energy Technology Data Exchange (ETDEWEB)

Popov, D; Trichkova, P

1976-01-01

Under the conditions of experimental acute radiation disease the authors study the tendon tissue regeneration after suture of the lateral part of the gastrocnemius muscle tendon. Tendon auto and alloplasty were applied. In four postoperative periods the histological features are described in details as well as the characteristic phenomena observed during the regeneration influenced to a considerable degree by the irradiation. Round cell infiltration, large necrotic zones, erythrocyte infiltrations as well as predominance of non-specific tendon regeneration long after the surgery characterize the recovery period of the traumatically damaged tendon, nevertheless that at the end there is real tendon regeneration even though in a longer period in comparison with the controls (non-irradiated animals).

Tissue-Engineered Skin Substitute Enhances Wound Healing after Radiation Therapy.

Science.gov (United States)

Busra, Mohd Fauzi bin Mh; Chowdhury, Shiplu Roy; bin Ismail, Fuad; bin Saim, Aminuddin; Idrus, Ruszymah Bt Hj

2016-03-01

When given in conjunction with surgery for treating cancer, radiation therapy may result in impaired wound healing, which, in turn, could cause skin ulcers. In this study, bilayer and monolayer autologous skin substitutes were used to treat an irradiated wound. A single dose of 30 Gy of linear electron beam radiation was applied to the hind limb of nude mice before creating the skin lesion (area of 78.6 mm). Monolayer tissue-engineered skin substitutes (MTESSs) were prepared by entrapping cultured keratinocytes in fibrin matrix, and bilayer tissue-engineered skin substitutes (BTESSs) were prepared by entrapping keratinocytes and fibroblasts in separate layers. Bilayer tissue-engineered skin substitute and MTESS were implanted to the wound area. Gross appearance and wound area were analyzed to evaluate wound healing efficiency. Skin regeneration and morphological appearance were observed via histological and electron microscopy. Protein expressions of transforming growth factor β1 (TGF-β1), platelet-derived growth factor BB (PDGF-BB), and vascular endothelial growth factor (VEGF) in skin regeneration were evaluated by immunohistochemistry (IHC). Macroscopic observation revealed that at day 13, treatments with BTESS completely healed the irradiated wound, whereas wound sizes of 1.1 ± 0.05 and 6.8 ± 0.14 mm were measured in the MTESS-treated and untreated control groups, respectively. Hematoxylin-eosin (H&E) analysis showed formation of compact and organized epidermal and dermal layers in the BTESS-treated group, as compared with MTESS-treated and untreated control groups. Ultrastructural analysis indicates maturation of skin in BTESS-treated wound evidenced by formation of intermediate filament bundles in the dermal layer and low intercellular space in the epidermal layer. Expressions of TGF-β1, PDGF-BB, and VEGF were also higher in BTESS-treated wounds, compared with MTESS-treated wounds. These results indicate that BTESS is the preferred treatment for

Actinomyces associated with persistent vaginal granulation tissue.

OpenAIRE

Wai, Clifford Y; Nihira, Mikio A; Drewes, Peter G; Chang, Joe S; Siddiqui, Momin T; Hemsell, David L

2005-01-01

BACKGROUND: We report a case of symptomatic actinomycosis associated with vaginal suture erosion and granulation tissue refractory to conservative management, in an outpatient setting. CASE: Three months after total vaginal hysterectomy and uterosacral ligament vaginal vault suspension, a woman complained of painless, intermittent vaginal discharge and spotting. Despite cauterization of granulation tissue, vaginal spotting persisted for another month. On re-examination, braided polyester sutu...

CT imaging of necrosive fasciitis

International Nuclear Information System (INIS)

Schulze, M.; Overkamp, D.; Joanoviciu, S.; Horger, M.

2008-01-01

NF is a rare but dramatic and often fatal infection of the fascii and adjoining soft tissues. Contrary to the Fournier's definition, it is most common in elderly people. Patients with immune problems have a higher risk (e.g. Diabetes mellitus, alcohol or drug abuse, AIDS, leukaemia, chemotherapy and immunosuppressive medication). Predisposition factors are diverticulitis, insect bites, or surgical interventions (Uppot RN, Levy HM, PLatel PH, Radiology 2003; 226; 115; Wysoki MG, Santora TA, Shah RM et al. Necrotizing fasciitis: CT characteristics, Radiology 1997; 203;859). Men are affected more frequently than women. In principle, NF may occur everywhere in the body but incidence in the region of the scrotum, perineum and lower extremities are the most common. (orig.)

Effect of gamma-radiation on callus initiation and oraganogenesis in the tissue culture of Nicotiana tabaccum L

International Nuclear Information System (INIS)

Shin, S. H.; Kim, J. G.; Song, H. S.

2004-01-01

It is generally agreed that ionizing radiations stimulate cell division, growth and development in various organisms including animals and plants. Differentiating tissues are the most sensitive to radiation. The present experiment was carried out to investigate the effects of ionizing radiation on callus initiation and organogenesis from the stem in the culture of Nicotiana tabaccum L. cv. When the stem segments were cultured on a Murashige and Skoog (MS) medium with 2 mg/L kinetin, with 1 mg/L 2,4-Dichlorophenoxyacetic acid (2,4-D), with 2 mg/L kinetin and 1 mg/L 2,4-D, the shoots and callus were differentiated 14 days after cultivation. Callus was especially formed on the MS medium with 2,4-D and/or kinetin and the formation was promoted by 1 Gy and 5 Gy of gamma radiation. The formation of the shoot clusters on the MS medium with 2 mg/L kinetin were prominent in the 5 Gy-irradiated groups. It is concluded that that gamma radiation enhanced the callus initiation and organogenesis in the tissue culture of Nicotiana tabaccum L

Strategies for Discovery of Small Molecule Radiation Protectors and Radiation Mitigators

Directory of Open Access Journals (Sweden)

Joel S Greenberger

2012-01-01

Full Text Available Mitochondrial targeted radiation damage protectors (delivered prior to irradiation and mitigators (delivered after irradiation, but before the appearance of symptoms associated with radiation syndrome have been a recent focus in drug discovery for 1 normal tissue radiation protection during fractionated radiotherapy, and 2 radiation terrorism counter measures. Several categories of such molecules have been discovered: nitroxide-linked hybrid molecules, including GS-nitroxide, GS-nitric oxide synthase inhibitors, p53/mdm2/mdm4 inhibitors, and pharmaceutical agents including inhibitors of the phosphoinositide-3-kinase pathway and the anti-seizure medicine, carbamazepine. Evaluation of potential new irradiation dose modifying molecules to protect normal tissue includes: clonagenic radiation survival curves; assays for apoptosis and DNA repair, and irradiation-induced depletion of antioxidant stores. Studies of organ specific radioprotection and in total body irradiation-induced hematopoietic syndrome in the mouse model for protection/mitigation facilitate rational means by which to move candidate small molecule drugs along the drug discovery pipeline into clinical development.

Space Radiation Effects on Human Cells: Modeling DNA Breakage, DNA Damage Foci Distribution, Chromosomal Aberrations and Tissue Effects

Science.gov (United States)

Ponomarev, A. L.; Huff, J. L.; Cucinotta, F. A.

2011-01-01

Future long-tem space travel will face challenges from radiation concerns as the space environment poses health risk to humans in space from radiations with high biological efficiency and adverse post-flight long-term effects. Solar particles events may dramatically affect the crew performance, while Galactic Cosmic Rays will induce a chronic exposure to high-linear-energy-transfer (LET) particles. These types of radiation, not present on the ground level, can increase the probability of a fatal cancer later in astronaut life. No feasible shielding is possible from radiation in space, especially for the heavy ion component, as suggested solutions will require a dramatic increase in the mass of the mission. Our research group focuses on fundamental research and strategic analysis leading to better shielding design and to better understanding of the biological mechanisms of radiation damage. We present our recent effort to model DNA damage and tissue damage using computational models based on the physics of heavy ion radiation, DNA structure and DNA damage and repair in human cells. Our particular area of expertise include the clustered DNA damage from high-LET radiation, the visualization of DSBs (DNA double strand breaks) via DNA damage foci, image analysis and the statistics of the foci for different experimental situations, chromosomal aberration formation through DSB misrepair, the kinetics of DSB repair leading to a model-derived spectrum of chromosomal aberrations, and, finally, the simulation of human tissue and the pattern of apoptotic cell damage. This compendium of theoretical and experimental data sheds light on the complex nature of radiation interacting with human DNA, cells and tissues, which can lead to mutagenesis and carcinogenesis later in human life after the space mission.

Effect of heat and ionizing radiation on normal and neoplastic tissue of the C3H mouse

International Nuclear Information System (INIS)

Thrall, D.E.; Gillette, E.L.; Dewey, W.C.

1975-01-01

The radiation response of the skin of the C3H mouse was evaluated in terms of the dose of radiation required to produce moist desquamation completely surrounding the lower aspect of the hind leg by 21 days following irradiation (DD50-21). Irradiation of the leg under various conditions of local tissue oxygenation indicated that when the animals were breathing air (ambient conditions), the cells in the skin were not fully oxygenated. Heat was administered by immersing the leg for 15 min in 44.5 0 C water either immediately prior to or immediately following irradiation under various conditions of local tissue oxygenation. Heat administered following irradiation reduced the DD50-21 values by 724 rad for hyperbaric O 2 , 1210 rad for ambient, and 1656 rad for hypoxic conditions. Approximately these same rad equivalents were observed when heat was administered prior to irradiation, under hyperbaric O 2 and hypoxic conditions. However, administration of heat prior to irradiation under ambient conditions sensitized the cells to the effects of ionizing radiation. This sensitization was assumed to result from heat causing an increase in local tissue oxygenation prior to and at the time of irradiation. The effect of the heat dose administered under acute hypoxic conditions immediately prior to acute hypoxic irradiation was not significantly different from the protocol where heat was administered under ambient conditions immediately prior to acute hypoxic irradiation. This indicates an independence of the magnitude of the heat effect on the tissue oxygenation status at the time of heating. The response of the C3H mouse mammary adenocarcinoma to combined wet heat (Δ) and x radiation (X) administered under either hypoxic, ambient, or hyperbaric O 2 conditions of local tissue oxygenation was studied. (U.S.)

New look at radiative association in dense interstellar clouds

International Nuclear Information System (INIS)

Herbst, E.

1980-01-01

A corrected statistical theory of radiative association reactions is presented and discussed. Calculations are undertaken to determine the rate coefficients of a variety of radiative association reactions of possible importance in dense interstellar clouds. Our results confirm the suggestion of Smith and Adams that certain radiative association reactions occur quite rapidly at low temperature and are probably important in the synthesis of complex interstellar molecules

Malignant mesothelioma following radiation exposure

International Nuclear Information System (INIS)

Antman, K.H.; Corson, J.M.; Li, F.P.; Greenberger, J.; Sytkowski, A.; Henson, D.E.; Weinstein, L.

1983-01-01

Mesothelioma developed in proximity to the field of therapeutic radiation administered 10-31 years previously in four patients. In three, mesothelioma arose within the site of prior therapeutic radiation for another cancer. Mesothelioma in the fourth patient developed adjacent to the site of cosmetic radiation to a thyroidectomy scar. None of these four patients recalled an asbestos exposure or had evidence of asbestosis on chest roentgenogram. Lung tissue in one patient was negative for ferruginous bodies, a finding considered to indicate no significant asbestos exposure. Five other patients with radiation-associated mesothelioma have been reported previously, suggesting that radiation is an uncommon cause of human mesothelioma. Problems in the diagnosis of radiation-associated mesotheliomas are considered

Tissue kerma vs distance relationships for initial nuclear radiation from the atomic devices detonated over Hiroshima and Nagasaki

International Nuclear Information System (INIS)

Kerr, G.D.; Pace, J.V. III; Scott, W.H. Jr.

1983-06-01

Initial nuclear radiation is comprised of prompt neutrons and prompt primary gammas from an exploding nuclear device, prompt secondary gammas produced by neutron interactions in the environment, and delayed neutrons and delayed fission-product gammas from the fireball formed after the nuclear device explodes. These various components must all be considered in establishing tissue kerma vs distance relationships which describe the decrease of initial nuclear radiation with distance in Hiroshima and in Nagasaki. The tissue kerma at ground evel from delayed fission-product gammas and delayed neutrons was investigated using the NUIDEA code developed by Science Applications, Inc. This code incorporates very detailed models which can take into account such features as the rise of the fireball, the rapid radioactive decay of fission products in it, and the perturbation of the atmosphere by the explosion. Tissue kerma vs distance relationships obtained by summing results of these current state-of-the-art calculations will be discussed. Our results clearly show that the prompt secondary gammas and delayed fission-product gammas are the dominant components of total tissue kerma from initial nuclear radiation in the cases of the atomic (or pure-fission) devices detonated over Hiroshima and Nagasaki

Effect of combined 5-fluorouracil and radiation on murine hematopoietic tissue

International Nuclear Information System (INIS)

Nielsen, O.S.; Overgaard, J.; Von der Maase, H.

1988-01-01

The interaction of 5-fluorouracil (5-FU) and radiation in hematopoietic tissue was assessed as the survival of hematopoietic stem cells (CFUs) by means of the spleen colony assay. 5-FU was given intraperitoneally in the dose range 50-500 mg/kg body weight. In this dose range, stem cell survival decreased exponentially as a function of 5-FU dose. After 150 mg/kg of 5-FU alone, the stem cell survival rapidly decreased, reaching a minimum after 1-2 days. A similar regeneration was observed after 0.75 Gy radiation alone 5-FU given 15 min before whole-body irradiation resulted in a pronounced reduction in stem cell survival due to an increase in the slope of the radiation survival curve by a factor of 2.1. After combined 5-FU and radiation, the survival rapidly decreased to a minimum at day 1, and it showed only a slight increase within the next 7 days. After this delay, the stem cells regenerated with a doubling time of about 30 h, reaching pretreatment values on day 15. The delayed stem cell regeneration was not seen following 3.5 Gy radiation alone or 225 mg/kg 5-FU alone, which resulted in the same nadir of CFUs survival as found after the combined treatment. Thus, 5-FU greatly enhances the hematopoietic damage after radiation by reducing the number of surviving stem cells and delaying the stem cell regeneration. 24 refs.; 6 figs.; 1 table

Quantitative radiation dose-response relationships for normal tissues in man - I. Gustatory tissues response during photon and neutron radiotherapy

International Nuclear Information System (INIS)

Mossman, K.L.

1982-01-01

Quantitative radiation dose-response curves for normal gustatory tissue in man were studied. Taste function, expressed as taste loss, was evaluated in 84 patients who were given either photon or neutron radiotherapy for tumors in the head and neck region. Patients were treated to average tumor doses of 6600 cGy (photon) or 2200 cGy intervals for photon patients and 320-cGy intervals for neutron patients during radiotherapy. The dose-response curves for photons and neutrons were analyzed by fitting a four-parameter logistic equation to the data. Photon and neutron curves differed principally in their relative position along the dose axis. Comparison of the dose-response curves were made by determination of RBE. At 320 cGy, the lowest neutron dose at which taste measurements were made, RBE = 5.7. If this RBE is correct, then the therapeutic gain factor may be equal to or less than 1, indicating no biological advantage in using neutrons over photons for this normal tissue. These studies suggest measurements of taste function and evaluation of dose-response relationships may also be useful in quantitatively evaluating the efficacy of chemical modifiers of radiation response such as hypoxic cell radiosensitizers and radioprotectors

Radiation-associated colon cancer: A case report.

Science.gov (United States)

Sasaki, Kazuhito; Ishihara, Soichiro; Hata, Keisuke; Kiyomatsu, Tomomichi; Nozawa, Hiroaki; Kawai, Kazushige; Tanaka, Toshiaki; Nishikawa, Takeshi; Otani, Kensuke; Yasuda, Koji; Kaneko, Manabu; Murono, Koji; Abe, Hiroyuki; Morikawa, Teppei; Watanabe, Toshiaki

2017-06-01

Radiation-associated colon cancer is a rare clinical entity. We herein describe the case of a patient with radiation-associated colon cancer who had undergone low anterior resection for rectal cancer following preoperative radiotherapy. Certain characteristics of radiation-associated colon cancer are highlighted. The patient was a 48-year-old man who had undergone low anterior resection for rectal cancer following preoperative radiotherapy at a total dose of 50 Gy, at the age of 29 years. When the patient presented at the University of Tokyo Hospital, 19 years after the surgery, he complained of severe anal pain and frequent defecation. Colonoscopy revealed two flat tumors in the sigmoid colon, located 10 cm to the oral side of the anastomosis site, which were diagnosed as well-differentiated adenocarcinomas. In addition, colonoscopy identified five flat polyps near the tumors, which were resected endoscopically. Computed tomography and magnetic resonance imaging revealed a mass in the sigmoid colon and no evidence of distant metastasis. Laparoscopic-assisted intersphincteric resection of the rectum and sigmoid colon with diverting ileostomy was performed. There were no specific postoperative complications and the patient was discharged from the hospital on the 20th postoperative day. On pathological examination, the resected rectum and sigmoid colon contained two separate tumors and six flat polyps. The two tumors were diagnosed as well-differentiated adenocarcinomas with invasion of the subserosa and submucosa, respectively. A total of 17 regional lymph nodes without metastasis were resected. The six flat polyps were diagnosed as tubular adenomas. We herein present a case of a radiation-associated colon cancer in a patient who had undergone low anterior resection for rectal cancer following preoperative radiotherapy 19 years prior. Colonoscopic surveillance of radiation-associated colon cancer may be indicated for rectal cancer patients treated with preoperative

Mechanisms underlying cellular responses of cells from haemopoietic tissue to low dose/low LET radiation

Energy Technology Data Exchange (ETDEWEB)

Munira A Kadhim

2010-03-05

To accurately define the risks associated with human exposure to relevant environmental doses of low LET ionizing radiation, it is necessary to completely understand the biological effects at very low doses (i.e., less than 0.1 Gy), including the lowest possible dose, that of a single electron track traversal. At such low doses, a range of studies have shown responses in biological systems which are not related to the direct interaction of radiation tracks with DNA. The role of these “non-targeted” responses in critical tissues is poorly understood and little is known regarding the underlying mechanisms. Although critical for dosimetry and risk assessment, the role of individual genetic susceptibility in radiation risk is not satisfactorily defined at present. The aim of the proposed grant is to critically evaluate radiation-induced genomic instability and bystander responses in key stem cell populations from haemopoietic tissue. Using stem cells from two mouse strains (CBA/H and C57BL/6J) known to differ in their susceptibility to radiation effects, we plan to carefully dissect the role of genetic predisposition on two non-targeted radiation responses in these models; the bystander effect and genomic instability, which we believe are closely related. We will specifically focus on the effects of low doses of low LET radiation, down to doses approaching a single electron traversal. Using conventional X-ray and γ-ray sources, novel dish separation and targeted irradiation approaches, we will be able to assess the role of genetic variation under various bystander conditions at doses down to a few electron tracks. Irradiations will be carried out using facilities in routine operation for bystander targeted studies. Mechanistic studies of instability and the bystander response in different cell lineages will focus initially on the role of cytokines which have been shown to be involved in bystander signaling and the initiation of instability. These studies also aim

Calculation of neutron radiation energy deposition distribution in subcellular parts of tissue using recombination chamber microdosimetry

International Nuclear Information System (INIS)

Golnik, N.; Zielczynski, M.

1999-01-01

Recombination chamber microdosimetry was used as an instrument for determination of local neutron radiation energy deposition distribution. The method allows to simulate of subcellular regions of tissue of the order of 70 nm in size. The results obtained qualitatively correspond to relationship between biological efficiency and neutron energy, and show regular differences of distributions achieved by the recombination method and distributions measured using tissue equivalent proportional counters (TEPC), which simulates greater tissue regions of 1 μm in size

The role of connective tissue in late effects of radiation

International Nuclear Information System (INIS)

Gerber, G.B.

1979-01-01

Connective tissues not only serve as support, but also filter and censor the physical and molecular information reaching cells. The late change in connective tissues, i.e. fibrosis several months or years after the irradiation with 1000 rad or more, has been well known, and the dreaded sequel of radiation therapy, but connective tissues are affected already at much earlier time. The change in irradiated connective tissues may be distinguished in 3 phases after irradiation, the change in permeability within hours, damage to cell replacement systems within days and months and the late change of fibrosis, vascular damage and parenchymal atrophy after months and years. Glomerular sclerosis, tubular atrophy and interstitial fibrosis after the excessive irradiation of kidneys, accompanied by renal failure and hypertension, are usually considered as the consequence of vascular or tubular damage, but recent investigation suggested that the change in blood flow is correlated also with the increase in collagen, so that fibrosis may represent an important factor in the pathogenesis of renal damage. Radiofibrosis is considered simply as a result of the vascular damage due to the deficient or abnormal replacement of endothelial cells and/or due to arteriolo-capillary fibrosis. The late effects depend on early ones, and the endothelial cells would be only one. Other possible paths could depend on low fibrinolytic activity and immunological reactions. (Yamashita, S.)

The experimental study of radiation injury on bile duct and liver tissue

International Nuclear Information System (INIS)

Cao Guiwen; Wang Bin; Sun Yequan; Shao Xueye; Ning Houfa; Sui Shouguang; Wang Xiuchun; Bai Xuming

2007-01-01

Objective: To investigate the safety, acceptance and the effective extent of 192 Ir-internal irradiation, providing theoretical guidelines for HC. Methods: Sixteen male healthy hybrid dogs enrolled in the experiment were divided into 4 groups of 4 each. The brachytherapy applicator was introduced from gall bladder into the convergence of cystic duct with common hepatic duct during the operation and a small chip of 1 cm 3 liver tissue was cut off and taken for control later on. The animals in group A-D were irradiated by 192 Ir-internal irradiation with 30 Gy, 40 Gy, 50 Gy arid 60 Gy at the correlative dose points respectively. Animals were put to death after 10 days subsequently, with sampling specimens obtained from radiation cystic duct and the in between liver tissue with the distant cystic duct. The radiation injury of the cystic duct and liver tissue near bile ducts were observed and studied by light microscope and transmission election microscope. Results: By the limit of the safest endurance dose(50 Gy) of Bile duct, unreversed injury of the nuclei of liver cells occurred at 0 to 15 mm from bile duct revealed by transmission electron microscope and light microscope. The whole biliary duct wall would be undergone necrosis with irradiation dose over 60 Gy. Conclusions: Normal bile duct possesses good endurance to 192 Ir-internal irradiation. Within the safest endurance limit of 50 Gy the effective irradiation field could reach 15 mm from the involved bile duct. (authors)

Acoustic Radiation Force-Induced Creep-Recovery (ARFICR): A Noninvasive Method to Characterize Tissue Viscoelasticity.

Science.gov (United States)

Amador Carrascal, Carolina; Chen, Shigao; Urban, Matthew W; Greenleaf, James F

2018-01-01

Ultrasound shear wave elastography is a promising noninvasive, low cost, and clinically viable tool for liver fibrosis staging. Current shear wave imaging technologies on clinical ultrasound scanners ignore shear wave dispersion and use a single group velocity measured over the shear wave bandwidth to estimate tissue elasticity. The center frequency and bandwidth of shear waves induced by acoustic radiation force depend on the ultrasound push beam (push duration, -number, etc.) and the viscoelasticity of the medium, and therefore are different across scanners from different vendors. As a result, scanners from different vendors may give different tissue elasticity measurements within the same patient. Various methods have been proposed to evaluate shear wave dispersion to better estimate tissue viscoelasticity. A rheological model such as the Kelvin-Voigt model is typically fitted to the shear wave dispersion to solve for the elasticity and viscosity of tissue. However, these rheological models impose strong assumptions about frequency dependence of elasticity and viscosity. Here, we propose a new method called Acoustic Radiation Force Induced Creep-Recovery (ARFICR) capable of quantifying rheological model-independent measurements of elasticity and viscosity for more robust tissue health assessment. In ARFICR, the creep-recovery time signal at the focus of the push beam is used to calculate the relative elasticity and viscosity (scaled by an unknown constant) over a wide frequency range. Shear waves generated during the ARFICR measurement are also detected and used to calculate the shear wave velocity at its center frequency, which is then used to calibrate the relative elasticity and viscosity to absolute elasticity and viscosity. In this paper, finite-element method simulations and experiments in tissue mimicking phantoms are used to validate and characterize the extent of viscoelastic quantification of ARFICR. The results suggest that ARFICR can measure tissue

Intoxicação por veneno de cobra: necrose symetrica da cortex renal: uremia

Directory of Open Access Journals (Sweden)

A. Penna de Azevedo

1938-01-01

Full Text Available Em um caso fatal de ophidismo, em individuo de 15 annos de edade, picado por uma cobra jararaca (Bothrops jararaca na face externa da perna direita e que veio a fallecer 26 dias apoz o accidente, os A.A, descrevem as lesões anatomo-pathologicas encontradas e as modificações do metabolismo, evidenciadas pelos exames chimicos do sangue. As principaes alterações existentes, acham-se localisadas nos rins os quaes apresentam lesões de glomerulonephrite diffusa e o aspecto typico da necrose cortical symmetrica. Como alterações de maior significação observam-se ainda lesões vasculares de grande intensidade e constituidas essencialmente por processo de endoarterite productiva. A necrose symmetrica da cortex renal, a vista das intensas alterações vasculares (endoarterite productiva que acarretaram a obliteração das arterías, é considerada como a consequencia immediata de taes lesões vasculares. Os vasos renaes, séde do processo inflammatorio, são as arterias interlobar, arciforme e interlobular, mas principalmente as arteriolares da camada cortical. O processo de endoarterite assume sempre o carater progressivo, de modo que a luz vascular vae sendo aos poucos, totalmente obstruida. Ao contrario do que se tem observado nos casos de necrose cortical symmetrica, citados na literatura, em que as alterações parenchymatosas são consequentes a thrombose dos vasos reanes, no caso presente esse aspecto não foi verificado mas tão sómente a existencia da endoarterite productiva obliterante. Consideram os A.A. as lesões renaes no caso que estudaram, como a resultante da actuação lenta e prolongada do veneno de cobra sobre as estructuras renaes, baseados nos seguintes factos já conhecidos e admittidos: eliminação do veneno de cobra pelos rins; capacidade do mesmo veneno, determinar a glomerulo-nephrite diffusa e acção do veneno de cobra sobre o endothelio vascular, facilitada essencialmente pela funcção especifica do orgão. As

Study of a number of biochemical indices of the blood and tissue of dogs after prolonged gamma-radiation

Science.gov (United States)

Alers, I.; Alersova, E.; Praslichka, T.; Mishurova, E.; Sedlakova, A.; Malatova, Z.; Akhunov, A. A.; Markelov, B. A.

1974-01-01

The glucose content in blood and the lipid content in serum and tissues of dogs exposed to chronic radiation for 3 and 5 years were studied. In tissues of these animals, the concentration of soluble DNA and DNA contained in DNP was studied in the spleen, lymph node (deep cervical node) and bone marrow of thigh bones. Results indicate that chronic gamma irradiation significantly changes concentrations of glucose in the blood, and that of several lipids in serum and tissues. A reduction in the concentration of DNP in tested organs reflects changes in the relative number of cells with various nuclear cytoplasmic ratios; most pronounced changes in biochemical indices occur in dogs exposed to chronic gamma radiation in doses of 125 rad per year.

Radiation-induced changes in production of prostaglandins Fsub(2α), E, and thromboxane B2 in guinea pig parenchymal lung tissues

International Nuclear Information System (INIS)

Steel, L.K.; Catravas, G.N.

1982-01-01

At 1 hour to 4 days after unilateral exposure of guinea pigs to a single dose (0.5, 1.5, or 3.0 Gy) of gamma-radiation, changes were detected in prostaglandin and thromboxane concentrations in parenchymal lung tissues. At 1-3 hours after exposure, tissue levels of PGFsub(2α), PGE, and thromboxane B 2 were significantly elevated in animals receiving 3.0 Gy, with the magnitude of alteration revealing a radiation dose effect. By 24 hours, tissue prostaglandin and thromboxane levels returned to near control values. Lung tissue synthesis of prostaglandins in response to H-1 receptor stimulation by the exogenous addition of histamine revealed similar radiation dose effects. The carboxylic acid ionophore A23187, exogenously applied to lung tissues, revealed a transient peak of increased sensitivity to ionophore stimulation for TxB 2 synthesis at 24 hours and for PGFsub(2α) at 72 hours post-irradiation. The data suggest that significant alterations in prostaglandin and thromboxane concentrations in parenchymal lung tissues occur following irradiation, in a dose-dependent manner, and that altered responsiveness to H-1 receptor stimulation and divalent cation transport also occur

Effect of gamma radiation on tissue elastin content and serum elastolytic activity in rats

International Nuclear Information System (INIS)

Drozdz, M.; Olczyk, K.; Piwowarczyk, B.; Stawiarska, B.

1981-01-01

The elastin content of aorta, heart, skin and lungs as well as the serum elastolytic activity were determined in rats exposed to radiation. It was found that a single irradiation of rats with gamma rays (500 r) caused a decrease of the elastin content in all examined tissues. The serum elastolytic activity in the irradiated rats was increased. It is suggested that elastin degradation following radiation may be caused by changes in its molecular structure and possibly, due to increased serum elastolytic activity. (author)

Radiation Retinopathy Associated with Central Retinal Vein Occlusion

Institute of Scientific and Technical Information of China (English)

Yan; Liu; FengWen

2007-01-01

Purpose: To report a case of radiation retinopathy associated with central retinal vein occlusion.Methods: The clinical features and fundus fluorescein angiography of this case were analyzed.Results: The patient had been treated with radiotherapy for her nasopharyngeal carcinoma, and presented with sudden visual loss in the left eye. The funduscopic examination and fluorescein angiography showed the features of radiation retinopathy in both eyes, and central retinal vein occlusion in the left eye.Conclusions: Radiation retinopathy can be associated with central retinal vein occlusion in the same eye, and it seems that the endothelial cell loss caused by radiation retinopathy may lead to retinal vein occlusion.

Chemical protection from high LET radiation

International Nuclear Information System (INIS)

Ando, Koichi; Koike, Sachiko; Matsushita, Satoru; Kanai, Tatsuaki; Ohara, Hiroshi

1992-01-01

Radioprotection by WR151327 from high LET fast neutrons was investigated and compared with that from low LET radiation. Radiation damage in bone marrow, intestine, skin and leg length were all protected by a pretreatment with 400 mg/kg WR151327. Most prominent protection was observed for bone marrow, which gave a Dose Modifying Factor (DMF) of 2.2 against γ rays. Identical protection was observed between early and late radiation damage. WR151327 protected fast neutrons less efficiently than γ rays; 40% for bone marrow and 80% for skin leg. Pathological findings indicated that hyperplastic change in both dermis and epidermis associated with late skin shrinkage. Laser doppler flow-metry showed a good relationship between reduction of blood flow and late skin shrinkage. Irradiation of skin by heavy particle Carbon-12 indicated that skin shrinkage was modified by unirradiated surrounding normal tissues, which proposed a significant role of 'Volume Effect' in radiation damage. Tumor tissues were less protected by WR151327 than normal tissues. Dependence of radioprotection by WR151327 on tissue oxygen concentration is a probable reason to explain the difference between normal and tumor tissues. (author)

Stochastic Threshold Exponential (TE) Model for Hematopoietic Tissue Reconstitution Deficit after Radiation Damage.

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Scott, B R; Potter, C A

2014-07-01

Whole-body exposure to large radiation doses can cause severe loss of hematopoietic tissue cells and threaten life if the lost cells are not replaced in a timely manner through natural repopulation (a homeostatic mechanism). Repopulation to the baseline level N 0 is called reconstitution and a reconstitution deficit (repopulation shortfall) can occur in a dose-related and organ-specific manner. Scott et al. (2013) previously introduced a deterministic version of a threshold exponential (TE) model of tissue-reconstitution deficit at a given follow-up time that was applied to bone marrow and spleen cellularity (number of constituent cells) data obtained 6 weeks after whole-body gamma-ray exposure of female C.B-17 mice. In this paper a more realistic, stochastic version of the TE model is provided that allows radiation response to vary between different individuals. The Stochastic TE model is applied to post gamma-ray-exposure cellularity data previously reported and also to more limited X-ray cellularity data for whole-body irradiated female C.B-17 mice. Results indicate that the population average threshold for a tissue reconstitution deficit appears to be similar for bone marrow and spleen and for 320-kV-spectrum X-rays and Cs-137 gamma rays. This means that 320-kV spectrum X-rays could successfully be used in conducting such studies.

Effective atomic numbers, electron densities, and tissue equivalence of some gases and mixtures for dosimetry of radiation detectors

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Singh Vishwanath P.

2012-01-01

Full Text Available Total mass attenuation coefficients, µm, effective atomic number, Zeff, and effective electron density, Neff, of different gases - carbon dioxide, methane, acetylene, propane, butane, and pentane used in radiation detectors, have been calculated for the photon energy of 1 keV to 100 GeV. Each gas has constant Zeff values between 0.10 to 10 MeV photon energies; however, these values are way far away from ICRU tissue. Carbon dioxide gas shows the closest tissue equivalence in the entire photon energy spectrum. Relative tissue equivalences of the mixtures of gases with respect to ICRU tissue are in the range of 0.998-1.041 for air, argon (4.5% + methane (95.5%, argon (0.5% + carbon dioxide (99.5%, and nitrogen (5% + methane (7% + carbon dioxide (88%. The gas composition of xenon (0.5% + carbon dioxide (99.5% shows 1.605 times higher tissue equivalence compared to the ICRU tissue. The investigated photon interaction parameters are useful for exposure and energy absorption buildup factors calculation and design, and fabrication of gaseous detectors for ambient radiation measurement by the Geiger-Muller detector, ionization chambers and proportional counters.

Synthetic Secoisolariciresinol Diglucoside (LGM2605 Protects Human Lung in an Ex Vivo Model of Proton Radiation Damage

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Anastasia Velalopoulou

2017-11-01

Full Text Available Radiation therapy for the treatment of thoracic malignancies has improved significantly by directing of the proton beam in higher doses on the targeted tumor while normal tissues around the tumor receive much lower doses. Nevertheless, exposure of normal tissues to protons is known to pose a substantial risk in long-term survivors, as confirmed by our work in space-relevant exposures of murine lungs to proton radiation. Thus, radioprotective strategies are being sought. We established that LGM2605 is a potent protector from radiation-induced lung toxicity and aimed in the current study to extend the initial findings of space-relevant, proton radiation-associated late lung damage in mice by looking at acute changes in human lung. We used an ex vivo model of organ culture where tissue slices of donor living human lung were kept in culture and exposed to proton radiation. We exposed donor human lung precision-cut lung sections (huPCLS, pretreated with LGM2605, to 4 Gy proton radiation and evaluated them 30 min and 24 h later for gene expression changes relevant to inflammation, oxidative stress, and cell cycle arrest, and determined radiation-induced senescence, inflammation, and oxidative tissue damage. We identified an LGM2605-mediated reduction of proton radiation-induced cellular senescence and associated cell cycle changes, an associated proinflammatory phenotype, and associated oxidative tissue damage. This is a first report on the effects of proton radiation and of the radioprotective properties of LGM2605 on human lung.

In vitro evaluation of ionizing radiation effects in bone tissue by FTIR spectroscopy and dynamic mechanical analysis

International Nuclear Information System (INIS)

Veloso, Marcelo Noronha

2013-01-01

Ionizing radiation from gamma radiation sources or X-ray generators is frequently used in Medical Science, such as radiodiagnostic exams, radiotherapy, and sterilization of haloenxerts. Ionizing radiation is capable of breaking polypeptidic chains and causing the release of free radicals by radiolysis.of water. It interacts also with organic material at the molecular level, and it may change its mechanical properties. In the specific case of bone tissue, studies report that ionizing radiation induces changes in collagen molecules and reduces the density of intermolecular crosslinks. The aim of this study was to verify the changes promoted by different doses of ionizing radiation in bone tissue using Fourier Transform Infrared Spectroscopy (FTIR) and dynamic mechanical analysis (DMA). Samples of bovine bone were irradiated using Cobalt-60 with five different doses: 0.01 kGy, 0.1 kGy, 1 kGy, 15 kGy and 75 kGy. To study the effects of ionizing irradiation on the chemical structure of the bone, the sub-bands of amide I, the crystallinity index and relation of organic and inorganic materials, were studied. The mechanical changes were evaluated using the elastic modulus and the damping value. To verify whether the chemical changes and the mechanical characteristics of the bone were correlated, the relation between the analysis made with spectroscopic data and the mechanical analysis data was studied. It was possible to evaluate the effects of different doses of ionizing radiation in bone tissue. With ATR-FTIR spectroscopy, it was possible to observe changes in the organic components and in the hydroxyapatite crystals organization. Changes were also observed in the elastic modulus and in the damping value. High correlation with statistical significance was observed among (amide III + collagen)/ v1,v3 , PO 4 3- and the delta tangent, and among 1/FHWM and the elastic modulus. (author)

Characteristics of liver tissue for attenuate the gamma radiation; Caracteristicas del tejido hepatico para atenuar la radiacion gamma

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Arcos P, A.; Rodriguez N, S.; Pinedo S, A.; Amador V, P.; Chacon R, A.; Vega C, H.R. [Unidad Academica de Estudios Nucleares, Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas (Mexico)

2005-07-01

It was determined the lineal attenuation coefficient of hepatic tissue before gamma radiation of a source of {sup 137} Cs. When exposing organic material before X or gamma radiation fields, part of the energy of the photons is absorbed by the material, while another part crosses it without producing any effect. The quantity of energy that is absorbed is a measure of the dose that receives the material. The three main mechanisms by means of which the gamma rays interacting with the matter are: The Photoelectric Effect, the Compton dispersion and the Even production; the sum of these three processes is translated in the attenuation coefficient of the radiation. In this work we have used hepatic tissue of bovine, as substitute of the human hepatic tissue, and we have measured the lineal attenuation coefficient for photons of 0.662 MeV. Through a series of calculations we have determined the lineal attenuation coefficient for photons from 10{sup -3} to 10{sup -5} MeV and the measured coefficient was compared with the one calculated. (Author)

Assessment of cone beam CT registration for prostate radiation therapy: fiducial marker and soft tissue methods.

Science.gov (United States)

Deegan, Timothy; Owen, Rebecca; Holt, Tanya; Fielding, Andrew; Biggs, Jennifer; Parfitt, Matthew; Coates, Alicia; Roberts, Lisa

2015-02-01

This investigation aimed to assess the consistency and accuracy of radiation therapists (RTs) performing cone beam computed tomography (CBCT) alignment to fiducial markers (FMs) (CBCTFM ) and the soft tissue prostate (CBCTST ). Six patients receiving prostate radiation therapy underwent daily CBCTs. Manual alignment of CBCTFM and CBCTST was performed by three RTs. Inter-observer agreement was assessed using a modified Bland-Altman analysis for each alignment method. Clinically acceptable 95% limits of agreement with the mean (LoAmean ) were defined as ±2.0 mm for CBCTFM and ±3.0 mm for CBCTST . Differences between CBCTST alignment and the observer-averaged CBCTFM (AvCBCTFM ) alignment were analysed. Clinically acceptable 95% LoA were defined as ±3.0 mm for the comparison of CBCTST and AvCBCTFM . CBCTFM and CBCTST alignments were performed for 185 images. The CBCTFM 95% LoAmean were within ±2.0 mm in all planes. CBCTST 95% LoAmean were within ±3.0 mm in all planes. Comparison of CBCTST with AvCBCTFM resulted in 95% LoA of -4.9 to 2.6, -1.6 to 2.5 and -4.7 to 1.9 mm in the superior-inferior, left-right and anterior-posterior planes, respectively. Significant differences were found between soft tissue alignment and the predicted FM position. FMs are useful in reducing inter-observer variability compared with soft tissue alignment. Consideration needs to be given to margin design when using soft tissue matching due to increased inter-observer variability. This study highlights some of the complexities of soft tissue guidance for prostate radiation therapy. © 2014 The Royal Australian and New Zealand College of Radiologists.

Assessment of cone beam CT registration for prostate radiation therapy: fiducial marker and soft tissue methods

International Nuclear Information System (INIS)

Deegan, Timothy; Owen, Rebecca; Holt, Tanya; Fielding, Andrew; Biggs, Jennifer; Parfitt, Matthew; Coates, Alicia; Roberts, Lisa

2015-01-01

This investigation aimed to assess the consistency and accuracy of radiation therapists (RTs) performing cone beam computed tomography (CBCT) alignment to fiducial markers (FMs) (CBCT FM ) and the soft tissue prostate (CBCT ST ). Six patients receiving prostate radiation therapy underwent daily CBCTs. Manual alignment of CBCT FM and CBCT ST was performed by three RTs. Inter-observer agreement was assessed using a modified Bland–Altman analysis for each alignment method. Clinically acceptable 95% limits of agreement with the mean (LoA mean ) were defined as ±2.0 mm for CBCT FM and ±3.0 mm for CBCT ST . Differences between CBCT ST alignment and the observer-averaged CBCT FM (AvCBCT FM ) alignment were analysed. Clinically acceptable 95% LoA were defined as ±3.0 mm for the comparison of CBCT ST and AvCBCT FM . CBCT FM and CBCT ST alignments were performed for 185 images. The CBCT FM 95% LoA mean were within ±2.0 mm in all planes. CBCT ST 95% LoA mean were within ±3.0 mm in all planes. Comparison of CBCT ST with AvCBCT FM resulted in 95% LoA of −4.9 to 2.6, −1.6 to 2.5 and −4.7 to 1.9 mm in the superior–inferior, left–right and anterior–posterior planes, respectively. Significant differences were found between soft tissue alignment and the predicted FM position. FMs are useful in reducing inter-observer variability compared with soft tissue alignment. Consideration needs to be given to margin design when using soft tissue matching due to increased inter-observer variability. This study highlights some of the complexities of soft tissue guidance for prostate radiation therapy.

Connective Tissue Disorder-Associated Vasculitis.

Science.gov (United States)

Sharma, Aman; Dhooria, Aadhaar; Aggarwal, Ashish; Rathi, Manish; Chandran, Vinod

2016-06-01

Vasculitides secondary to connective tissue diseases are classified under the category of 'vasculitis associated with systemic disease' in the revised International Chapel Hill Consensus Conference (CHCC) nomenclature. These secondary vasculitides may affect any of the small, medium or large vessels and usually portend a poor prognosis. Any organ system can be involved and the presentation would vary depending upon that involvement. Treatment depends upon the type and severity of presentation. In this review, we describe secondary vasculitis associated with rheumatoid arthritis, systemic lupus erythematosus, sarcoidosis, relapsing polychondritis, systemic sclerosis, Sjogren's syndrome and idiopathic inflammatory myositis, focusing mainly on recent advances in the past 3 years.

Rates of Reconstruction Failure in Patients Undergoing Immediate Reconstruction With Tissue Expanders and/or Implants and Postmastectomy Radiation Therapy

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Fowble, Barbara, E-mail: BFowble@radonc.ucsf.edu [Department of Radiation Oncology, University of California San Francisco, San Francisco, California (United States); Park, Catherine [Department of Radiation Oncology, University of California San Francisco, San Francisco, California (United States); Wang, Frederick; Peled, Anne [Division of Plastic and Reconstructive Surgery, University of California San Francisco, San Francisco, California (United States); Alvarado, Michael; Ewing, Cheryl; Esserman, Laura [Carol Franc Buck Breast Care Center, Department of Surgery, University of California San Francisco, San Francisco, California (United States); Foster, Robert; Sbitany, Hani [Division of Plastic and Reconstructive Surgery, University of California San Francisco, San Francisco, California (United States); Hanlon, Alex [University of Pennsylvania School of Nursing, Philadelphia, Pennsylvania (United States)

2015-07-01

Objectives: Mastectomy rates for breast cancer have increased, with a parallel increase in immediate reconstruction. For some women, tissue expander and implant (TE/I) reconstruction is the preferred or sole option. This retrospective study examined the rate of TE/I reconstruction failure (ie, removal of the TE or I with the inability to replace it resulting in no final reconstruction or autologous tissue reconstruction) in patients receiving postmastectomy radiation therapy (PMRT). Methods and Materials: Between 2004 and 2012, 99 women had skin-sparing mastectomies (SSM) or total nipple/areolar skin-sparing mastectomies (TSSM) with immediate TE/I reconstruction and PMRT for pathologic stage II to III breast cancer. Ninety-seven percent had chemotherapy (doxorubicin and taxane-based), 22% underwent targeted therapies, and 78% had endocrine therapy. Radiation consisted of 5000 cGy given in 180 to 200 cGy to the reconstructed breast with or without treatment to the supraclavicular nodes. Median follow-up was 3.8 years. Results: Total TE/I failure was 18% (12% without final reconstruction, 6% converted to autologous reconstruction). In univariate analysis, the strongest predictor of reconstruction failure (RF) was absence of total TE/I coverage (acellular dermal matrix and/or serratus muscle) at the time of radiation. RF occurred in 32.5% of patients without total coverage compared to 9% with coverage (P=.0069). For women with total coverage, the location of the mastectomy scar in the inframammary fold region was associated with higher RF (19% vs 0%, P=.0189). In multivariate analysis, weight was a significant factor for RF, with lower weight associated with a higher RF. Weight appeared to be a surrogate for the interaction of total coverage, thin skin flaps, interval to exchange, and location of the mastectomy scar. Conclusions: RFs in patients receiving PMRT were lowered with total TE/I coverage at the time of radiation by avoiding inframammary fold incisions and

Radiotherapy for mucosa-associated lymphoid tissue lymphoma of the ocular adnexa

International Nuclear Information System (INIS)

Monzen, Yoshio; Wadasaki, Koichi; Hasebe, Haruyuki; Nishisaka, Takashi; Fukuhara, Toshiyuki

2011-01-01

We investigated the results of radiotherapy for mucosa-associated lymphoid tissue (MALT) lymphoma of the ocular adnexa. Twenty-one patients with MALT lymphoma of the ocular adnexa were treated with radiotherapy alone at a dose ranging from 30 to 54 Gy. The disease arose from the conjunctiva in 15 patients (9 with bilateral involvement), and from the retrobulbar space in 6 patients (1 with bilateral involvement). All patients with MALT lymphoma achieved a complete response (CR) or unconfirmed CR (CRu). The 5- and 10-year overall survival rates of all patients with MALT lymphoma were 100% and 90%, respectively. The 5- and 10-year cause-specific survival rates were 100% and 100%, respectively. In all patients with delayed toxicity, the radiation dose was more than 40 Gy. Excellent local control and survival can be achieved for patients with MALT lymphoma of the ocular adnexa using radiotherapy alone. (author)

Clinical oncology based upon radiation biology

International Nuclear Information System (INIS)

Hirata, Hideki

2016-01-01

This paper discussed the biological effects of radiation as physical energy, especially those of X-ray as electromagnetic radiation, by associating the position of clinical oncology with classical radiation cell biology as well as recent molecular biology. First, it described the physical and biological effects of radiation, cell death due to radiation and recovery, radiation effects at tissue level, and location information and dosage information in the radiotherapy of cancer. It also described the territories unresolved through radiation biology, such as low-dose high-sensitivity, bystander effects, etc. (A.O.)

The influence of parotid gland sparing on radiation damages of dental hard tissues.

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Hey, Jeremias; Seidel, Johannes; Schweyen, Ramona; Paelecke-Habermann, Yvonne; Vordermark, Dirk; Gernhardt, Christian; Kuhnt, Thomas

2013-07-01

The aim of the present study was to evaluate whether radiation damage on dental hard tissue depends on the mean irradiation dose the spared parotid gland is subjected to or on stimulated whole salivary flow rate. Between June 2002 and October 2008, 70 patients with neck and cancer curatively irradiated were included in this study. All patients underwent dental treatment referring to the guidelines and recommendations of the German Society of Dental, Oral and Craniomandibular Sciences prior, during, and after radiotherapy (RT). During the follow-up period of 24 months, damages on dental hard tissues were classified according to the RTOG/EORTC guidelines. The mean doses (D(mean)) during spared parotid gland RT were determined. Stimulated whole saliva secretion flow rates (SFR) were measured before RT and 1, 6, 12, 24 months after RT. Thirty patients showed no carious lesions (group A), 18 patients developed sporadic carious lesions (group B), and 22 patients developed general carious lesions (group C). Group A patients received a D mean of 21.2 ± 11.04 Gy. Group B patients received a D(mean) of 26.5 ± 11.59 Gy and group C patients received a D(mean) of 33.9 ± 9.93 Gy, respectively. The D(mean) of group A was significantly lower than the D(mean) of group C (p dental hard tissue correlates with increased mean irradiation doses as well as decreased salivary flow rates. Parotid gland sparing resulting in a dose below 20 Gy reduces radiation damage on dental hard tissues, and therefore, the dose may act as a predictor for the damage to be expected.

Ionizing Radiation Stimulates Expression of Pro-Osteoclastogenic Genes in Marrow and Skeletal Tissue

Science.gov (United States)

Alwood, J. S.; Shahnazari, M.; Chicana, B.; Schreurs, A. S.; Kumar, A.; Bartolini, A.; Shirazi-Fard, Y.; Globus, R. K.

2015-01-01

Exposure to ionizing radiation can cause rapid mineral loss and increase bone-resorbing osteoclasts within metabolically-active, cancellous-bone tissue leading to structural deficits. To better understand mechanisms involved in rapid, radiation-induced bone loss, we determined the influence of total-body irradiation on expression of select cytokines known both to stimulate osteoclastogenesis and contribute to inflammatory bone disease. Adult (16wk), male C57BL/6J mice were exposed to either 2Gy gamma rays (137Cs, 0.8Gy/min) or heavy ions (56Fe, 600MeV, 0.50-1.1Gy/min); this dose corresponds to either a single fraction of radiotherapy (typical total dose is =10Gy) or accumulates over long-duration, interplanetary missions. Serum, marrow, and mineralized tissue were harvested 4hrs-7d later. Gamma irradiation caused a prompt (2.6-fold within 4hrs) and persistent (peaking at 4.1-fold within 1d) rise in the expression of the obligate osteoclastogenic cytokine, receptor activator of nuclear factor kappaB-ligand (Rankl) within marrow cells over controls. Similarly, Rankl expression peaked in marrow cells within 3d of iron exposure (9.2-fold). Changes in Rankl expression induced by gamma irradiation preceded and overlapped with a rise in expression of other pro-osteoclastic cytokines in marrow (e.g., monocyte chemotactic protein-1 increased 11.9-fold, tumor necrosis factor-alpha increased 1.7- fold over controls). Marrow expression of the RANKL decoy receptor, osteoprotegerin (Opg), also rose after irradiation (11.3-fold). The ratio Rankl/Opg in marrow was increased 1.8-fold, a net pro-resorption balance. As expected, radiation increased a serum marker of resorption (tartrate resistant acid phosphatase) and led to cancellous bone loss (16% decrease in bone volume/total volume) through reduced trabecular struts. We conclude that total-body irradiation (gamma or heavy-ion) caused temporal, concerted regulation of gene expression within marrow and mineralized tissue for

Roentgen's heritage and radiation phobia, a challenge to radiation research and radiation protection

International Nuclear Information System (INIS)

Feinendegen, L.E.

1996-01-01

Present practice of applying linearity to assessing risk even from very low dose exposure of complex tissues to ionising radiation has been evaluated in terms of microdosimetric approach to energy deposition in tissues, nature of radiation and also the magnitudes of conditioning and challenging doses. This paper discusses the probability of radiation risk at quite low doses on the tissues in terms of simple mathematical terms. (author). 13 refs., 2 figs., 1 tab

Histopathology of tumour associated sarcoid-like stromal reaction in breast cancer. An analysis of 5 cases with immunohistochemical investigations.

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Bässler, R; Birke, F

1988-01-01

In 5 cases of invasive ductal and lobular carcinoma of the breast multiple epithelioid and giant cell containing granulomas were detected, localized mainly in circumferential regions, but also in the center of the carcinomas. These granulomas were interpreted as sarcoid-like stromal reactions, occurring as sarcoid-like lesions in uni- and bilateral primaries, in a recurrent tumour, and also in axillary lymph nodes. Histopathologically, these granulomas were not quite uniform, some of them corresponding to typical sarcoidosis, others showing marked proliferations of epithelioid or giant cells or containing fibrinoid exudate or necroses. The granulomas were surrounded by dense infiltrates of mononuclear cells. Tuberculosis and mycosis was excluded. There were no hints of generalized sarcoidosis. Pathogenetically, these are reactions in the tumour stroma of varying intensity, and are not caused by necroses of the tumour tissue nor by microbial infections. Such tumour-associated sarcoid-like stroma reactions are interpreted as a T-cell mediated immune response to an antigen expression of the carcinoma acting as the local trigger; in 2 cases they were connected with sarcoid-like lesions of the axillary lymph nodes. Their occurrence in bilateral carcinoma of the breast points to an immunological disposition for this special kind of host-versus-tumour response. The intensity of these changes in a recurrent tumour reflects an immunological hypersensitivity reaction. The pathogenetic and differential diagnostic aspects of epithelioid granulomas of the female breast in chronic granulomatous mastitis, panniculitis, foreign body reaction, rare infections, and in therapeutically induced sarcoidosis are described and discussed.

Transforming growth factor-β1/Smad/connective tissue growth factor axis: The main pathway in radiation-induced fibrosis of osteoradionecrosis?

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Qian Wei Zhuang

2013-01-01

Full Text Available Introduction: Osteoradionecrosis (ORN of the mandible is a serious complication following radiation therapy for malignancies of the head and neck. Radiation-induced fibrosis (RIF is a new theory that accounts for the damage to normal tissues after radiotherapy, and the radiation-induced fibroatrophic mechanism includes the free-radical formation, endothelial dysfunction, inflammation, microvascular thrombosis, fibrosis and remodeling, and finally bone and tissue necrosis. The Hypothesis: Previous studies revealed that transforming growth factor-β1 (TGF-β1 is the master switch cytokine responsible for the regulation of fibroblast proliferation and differentiation that result in RIF. Among the targets of TGF-β1, connective tissue growth factor (CTGF is a downstream mediator through the Smad3/4 pathway and plays an important role in connective tissue homeostasis and fibroblast proliferation. Studies have proved that the TGF-β1/Smad/CTGF signaling pathway is involved in the RIF of soft tissues, so the authors put forward a hypothesis that the TGF-β1/Smad/CTGF axis is also the main pathway in RIF of ORN. Evaluation of the Hypothesis: The validation of our hypothesis may provide new insights for better understanding the pathogenesis of ORN and open new perspectives for anti-fibrotic therapies, and pioneer novel approaches to treat ORN.

Proteomics analysis of apoptosis-regulating proteins in tissues with different radiosensitivity

International Nuclear Information System (INIS)

An, Jeung-Hee; Seong, Jin-Sil

2006-01-01

The aim of this study was to identify of radiosusceptibility proteins in tissues with different radiosensitivity. C3H/HeJ mice were exposed to 10 Gy. The tissues were processed for proteins extraction and were analyzed by 2-dimensional electrophoresis. The proteins were identified by matrix-assisted laser desorption ionizing time-of-flight mass spectrometry and validated by immunohistochemical staining and Western blotting. The peaks of apoptosis levels were 35.3±1.7% and 0.6±0.2% in the spleen and the liver, respectively, after ionizing radiation. Analysis of liver tissue showed that the expression level of reactive oxygen species (ROS) related proteins such as cytochrome c, glutathione S transferase, NADH dehydrogenase and peroxiredoxin VI increased after radiation. The expression level of cytochrome c increased to 3-fold after ionizing radiation in both tissues. However in spleen tissue, the expression level of various kinds of apoptosis regulating proteins increased after radiation. These involved iodothyronine, CD 59A glycoprotein precursor, fas antigen and tumor necrosis factor -inducible protein TSG-6nprecursor after radiation. The difference in the apoptosis index between the liver and spleen tissues is closely associated with the expression of various kinds of apoptosis-related proteins. The result suggests that the expression of apoptosis-related protein and redox proteins play important roles in this radiosusceptibility. (author)

The forward and inverse problem in tissue optics based on the radiative transfer equation: A brief review

International Nuclear Information System (INIS)

Klose, Alexander D.

2010-01-01

This note serves as an introduction to two papers by Klose et al. and provides a brief review of the latest developments in optical tomography of scattering tissue. We discuss advancements made in solving the forward model for light propagation based on the radiative transfer equation, in reconstructing scattering and absorption cross sections of tissue, and in molecular imaging of luminescent sources.

Radiation dose verification using real tissue phantom in modern radiotherapy techniques

International Nuclear Information System (INIS)

Gurjar, Om Prakash; Mishra, S.P.; Bhandari, Virendra; Pathak, Pankaj; Patel, Prapti; Shrivastav, Garima

2014-01-01

In vitro dosimetric verification prior to patient treatment has a key role in accurate and precision radiotherapy treatment delivery. Most of commercially available dosimetric phantoms have almost homogeneous density throughout their volume, while real interior of patient body has variable and varying densities inside. In this study an attempt has been made to verify the physical dosimetry in actual human body scenario by using goat head as 'head phantom' and goat meat as 'tissue phantom'. The mean percentage variation between planned and measured doses was found to be 2.48 (standard deviation (SD): 0.74), 2.36 (SD: 0.77), 3.62 (SD: 1.05), and 3.31 (SD: 0.78) for three-dimensional conformal radiotherapy (3DCRT) (head phantom), intensity modulated radiotherapy (IMRT; head phantom), 3DCRT (tissue phantom), and IMRT (tissue phantom), respectively. Although percentage variations in case of head phantom were within tolerance limit (< ± 3%), but still it is higher than the results obtained by using commercially available phantoms. And the percentage variations in most of cases of tissue phantom were out of tolerance limit. On the basis of these preliminary results it is logical and rational to develop radiation dosimetry methods based on real human body and also to develop an artificial phantom which should truly represent the interior of human body. (author)

Radiation dose verification using real tissue phantom in modern radiotherapy techniques

Directory of Open Access Journals (Sweden)

Om Prakash Gurjar

2014-01-01

Full Text Available In vitro dosimetric verification prior to patient treatment has a key role in accurate and precision radiotherapy treatment delivery. Most of commercially available dosimetric phantoms have almost homogeneous density throughout their volume, while real interior of patient body has variable and varying densities inside. In this study an attempt has been made to verify the physical dosimetry in actual human body scenario by using goat head as "head phantom" and goat meat as "tissue phantom". The mean percentage variation between planned and measured doses was found to be 2.48 (standard deviation (SD: 0.74, 2.36 (SD: 0.77, 3.62 (SD: 1.05, and 3.31 (SD: 0.78 for three-dimensional conformal radiotherapy (3DCRT (head phantom, intensity modulated radiotherapy (IMRT; head phantom, 3DCRT (tissue phantom, and IMRT (tissue phantom, respectively. Although percentage variations in case of head phantom were within tolerance limit (< ± 3%, but still it is higher than the results obtained by using commercially available phantoms. And the percentage variations in most of cases of tissue phantom were out of tolerance limit. On the basis of these preliminary results it is logical and rational to develop radiation dosimetry methods based on real human body and also to develop an artificial phantom which should truly represent the interior of human body.

Modulation of radiation induced DNA damage by natural products in hemopoietic tissue of mice

International Nuclear Information System (INIS)

Jayakumar, S.; Bhilwade, H.N.; Chaubey, R.C.

2014-01-01

Ionizing radiation is known to induce oxidative stress through generation of ROS leading to a variety of DNA lesions. However, the most dangerous DNA lesions which are responsible for the origin of lethal effects, mutagenesis, genomic instability and carcinogenesis are the DSBs. During recent years efforts are being made to identify phytochemicals, antioxidants or neutraxeuticals which can reduce harmful effect of radiation during accidental exposure or prevent normal tissue injury during radiotherapy. In the present study, we have investigated the radioprotective role of curcumin, a dietary antioxidant, taurine, malabaricone-C, and umbelliferone, for their radioprotective properties in hemopoietic cells of mice. Groups of mice-were fed 1% of curcumin in diet for three weeks. Similarly other groups of mice were injected i.p. with 50 mg/kg body weight of taurine for five consecutive days. After the completion of the treatment mice pre-treated with curcumin and taurine were exposed to 3 Gy of gamma rays. Malabaricone-C was tested for its radiomodulation potential in vitro, in spleenocytes of mouse. Spleenocytes were isolated and treated with different concentrations (0.5-25 ìM) of malabaricone-C. Immediately after irradiation, alkaline comet assay were performed using standard procedures. Twenty four post radiation exposure mice were sacrificed for micronucleus test. Results of these studies showed significant reduction in DNA damage by curcumin. The micronucleus data showed marginal increase in the frequency of micronucleated erythrocytes in curcumin fed group as compared to the controls. Mice receiving curcumin for 3 weeks in diet followed by gamma radiation (3 Gy), showed approximately 50% reduction in the frequency of micro nucleated polychromatic erythrocytes. Pre-treatment of mice with taurine significantly (p < 0.01) reduced the frequency of gamma rays induced mn-PCEs in bone marrow tissue. Malabaricone-C at 1.5 ìM concentration showed very good protection

Label-free protein profiling of formalin-fixed paraffin-embedded (FFPE) heart tissue reveals immediate mitochondrial impairment after ionising radiation.

Science.gov (United States)

Azimzadeh, Omid; Scherthan, Harry; Yentrapalli, Ramesh; Barjaktarovic, Zarko; Ueffing, Marius; Conrad, Marcus; Neff, Frauke; Calzada-Wack, Julia; Aubele, Michaela; Buske, Christian; Atkinson, Michael J; Hauck, Stefanie M; Tapio, Soile

2012-04-18

Qualitative proteome profiling of formalin-fixed, paraffin-embedded (FFPE) tissue is advancing the field of clinical proteomics. However, quantitative proteome analysis of FFPE tissue is hampered by the lack of an efficient labelling method. The usage of conventional protein labelling on FFPE tissue has turned out to be inefficient. Classical labelling targets lysine residues that are blocked by the formalin treatment. The aim of this study was to establish a quantitative proteomics analysis of FFPE tissue by combining the label-free approach with optimised protein extraction and separation conditions. As a model system we used FFPE heart tissue of control and exposed C57BL/6 mice after total body irradiation using a gamma ray dose of 3 gray. We identified 32 deregulated proteins (p≤0.05) in irradiated hearts 24h after the exposure. The proteomics data were further evaluated and validated by bioinformatics and immunoblotting investigation. In good agreement with our previous results using fresh-frozen tissue, the analysis indicated radiation-induced alterations in three main biological pathways: respiratory chain, lipid metabolism and pyruvate metabolism. The label-free approach enables the quantitative measurement of radiation-induced alterations in FFPE tissue and facilitates retrospective biomarker identification using clinical archives. Copyright © 2012 Elsevier B.V. All rights reserved.

Bacteria in a woody fungal disease: characterization of bacterial communities in wood tissues of esca-foliar symptomatic and asymptomatic grapevines

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Emilie eBruez

2015-10-01

Full Text Available Esca is a grapevine trunk disease (GTD associated with different pathogenic fungi inhabiting the woody tissues. Bacteria can also be found in such tissues and they may interact with these fungal colonizers. Although such types of microbial interaction have been observed for wood diseases in many trees, this has never been studied for grapevine. In this study, the bacterial microflora of different vine status (esca-symptomatic and asymptomatic, different anatomical part (trunk and cordon and different type of tissues (necrotic or not have been studied. Based on Single Strand Conformation Polymorphism (SSCP analyses, data showed that (i specific complexes of bacterial microflora colonize the wood of both necrotic and non-necrotic tissues of esca-foliar symptomatic and asymptomatic vines, and also that (ii depending on the anatomical part of the plant, cordon or trunk, differences could be observed between the bacterial communities. Such differences were also revealed through the Community-Level Physiological Profiling (CLPP with Biolog Ecoplates™. Two hundred seventeen bacterial strains were also isolated from plants samples and then assigned to bacterial species based on the 16S rRNA genes. Although Bacillus spp. and Pantoea agglomerans were the two most commonly isolated species from all kinds of tissues, various other taxa were also isolated. Inoculation of vine cuttings with 14 different bacterial species, and one GTD fungus, Neofusicoccum parvum, showed no impact of these bacteria on the size of the wood necroses caused by N. parvum. This study showed, therefore, that bacterial communities differ according to the anatomical part (trunk or cordon and/or the type of tissue (necrotic or non necrotic of wood of grapevine plants showing external symptoms of esca disease. However, research into bacteria having a role in GTD development needs further studies.

Ressonância magnética vs cintilografia com pirofosfato marcado com tecnécio-99m para a detecção de necrose miocárdica perioperatória Magnetic resonance vs technetium-99m pyrophosphate scintigraphy in the detection of perioperative myocardial necrosis

Directory of Open Access Journals (Sweden)

Guilherme Urpia Monte

2008-08-01

Full Text Available FUNDAMENTO: O infarto do miocárdio perioperatório (IMPO é uma complicação da cirurgia de revascularização miocárdica (CRM com potencial impacto prognóstico. A cintilografia miocárdica (CM com pirofosfato marcado com tecnécio-99m é utilizada no diagnóstico de IMPO, mas demonstra limitada sensibilidade para lesões subendocárdicas. A ressonância magnética cardiovascular (RMC, por sua vez, detém alta acurácia para a detecção de necrose miocárdica. OBJETIVO: Comparar a RMC e a CM para a detecção de IMPO após CRM. MÉTODOS: Foram estudados 24 pacientes portadores de doença arterial coronária crônica, com a técnica de realce tardio pela RMC e com a CM, antes e depois da CRM, analisando-se o surgimento de áreas de necrose miocárdica perioperatória (IMPO. Mensuraram-se também marcadores bioquímicos de lesão miocárdica (CKMB e troponina I, antes e depois da cirurgia. RESULTADOS: Dezenove pacientes completaram o estudo. Desses, 6 (32% apresentaram IMPO à RMC, e 4 (21% à CM (p = NS. Dos 323 segmentos do ventrículo esquerdo avaliados, 17 (5,3% exibiram necrose perioperatória à RMC, e 7 (2,2% à CM (p = 0,013. Observou-se moderada concordância entre os métodos (kappa = 0,46, havendo divergência, quanto ao diagnóstico de IMPO, em 4 (21% casos, a maioria com pequenas áreas de necrose perioperatória à RMC, não visualizadas à CM. Em todos os casos com IMPO à RMC, houve elevação significativa de CKMB e troponina I. CONCLUSÃO: Houve moderada concordância diagnóstica entre os métodos para a detecção de IMPO, mas a RMC permitiu a visualização de pequenas áreas de necrose miocárdica perioperatória, não identificadas pela CM e associadas à elevação de marcadores bioquímicos de lesão miocárdica.BACKGROUND: Perioperative myocardial infarction (POMI is a complication of coronary artery bypass grafting (CABG with a potential prognostic impact. Technetium-99m pyrophosphate myocardial scintigraphy (MS is

Proteinase-activated receptors - mediators of early and delayed normal tissue radiation responses

International Nuclear Information System (INIS)

Hauer-Jensen, M.

2003-01-01

Proteinase-activated receptors (PARs) are G-protein coupled receptors that are activated by proteolytic exposure of a receptor-tethered ligand. The discovery of this receptor family represents one of the most intriguing recent developments in signal transduction. PARs are involved in the regulation of many normal and pathophysiological processes, notably inflammatory and fibroproliferative responses to injury. Preclinical studies performed in our laboratory suggest that proteinase-activated receptor-1 (PAR-1) plays a critical role in the mechanism of chronicity of radiation fibrosis, while proteinase-activated receptor-2 (PAR-2) may mediate important fibroproliferative responses in irradiated intestine. Specifically, activation of PAR-1 by thrombin, and PAR-2 by pancreatic trypsin and mast cell proteinases, appears to be involved in acute radiation-induced inflammation, as well as in subsequent extracellular matrix deposition, leading to the development of intestinal wall fibrosis and clinical complications. Pharmacological modulators of PAR-1 or PAR-2 expression or activation would be potentially useful as preventive or therapeutic agents in patients who receive radiation therapy, especially if blockade could be targeted to specific tissues or cellular compartments

XRCC1 Polymorphism Associated With Late Toxicity After Radiation Therapy in Breast Cancer Patients

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Seibold, Petra; Behrens, Sabine [Division of Cancer Epidemiology, German Cancer Research Center, Heidelberg (Germany); Schmezer, Peter [Division of Epigenomics and Cancer Risk Factors, German Cancer Research Center, Heidelberg (Germany); Helmbold, Irmgard [Division of Cancer Epidemiology, German Cancer Research Center, Heidelberg (Germany); Barnett, Gillian; Coles, Charlotte [Department of Oncology, Oncology Centre, Cambridge University Hospital NHS Foundation Trust, United Kingdom (UK) (United Kingdom); Yarnold, John [Institute of Cancer Research and Royal Marsden NHS Foundation Trust, London (United Kingdom); Talbot, Christopher J. [Department of Genetics, University of Leicester, Leicester (United Kingdom); Imai, Takashi [Advanced Radiation Biology Research Program, National Institute of Radiological Sciences, Chiba (Japan); Azria, David [Department of Radiation Oncology and Medical Physics, I.C.M. – Institut regional du Cancer Montpellier, Montpellier (France); Koch, C. Anne [Radiation Medicine Program, Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario (Canada); Dunning, Alison M. [Centre for Cancer Genetic Epidemiology, University of Cambridge, Strangeways Research Laboratory, Cambridge (United Kingdom); Burnet, Neil [Department of Oncology, Oncology Centre, Cambridge University Hospital NHS Foundation Trust, University of Cambridge, Cambridge (United Kingdom); Bliss, Judith M. [The Institute of Cancer Research, Clinical Trials and Statistics Unit, Sutton (United Kingdom); Symonds, R. Paul; Rattay, Tim [Department of Cancer Studies and Molecular Medicine, University of Leicester, Leicester (United Kingdom); Suga, Tomo [Advanced Radiation Biology Research Program, National Institute of Radiological Sciences, Chiba (Japan); Kerns, Sarah L. [Department of Radiation Oncology, Icahn School of Medicine at Mount Sinai, New York, NH (United States); and others

2015-08-01

Purpose: To identify single-nucleotide polymorphisms (SNPs) in oxidative stress–related genes associated with risk of late toxicities in breast cancer patients receiving radiation therapy. Methods and Materials: Using a 2-stage design, 305 SNPs in 59 candidate genes were investigated in the discovery phase in 753 breast cancer patients from 2 prospective cohorts from Germany. The 10 most promising SNPs in 4 genes were evaluated in the replication phase in up to 1883 breast cancer patients from 6 cohorts identified through the Radiogenomics Consortium. Outcomes of interest were late skin toxicity and fibrosis of the breast, as well as an overall toxicity score (Standardized Total Average Toxicity). Multivariable logistic and linear regression models were used to assess associations between SNPs and late toxicity. A meta-analysis approach was used to summarize evidence. Results: The association of a genetic variant in the base excision repair gene XRCC1, rs2682585, with normal tissue late radiation toxicity was replicated in all tested studies. In the combined analysis of discovery and replication cohorts, carrying the rare allele was associated with a significantly lower risk of skin toxicities (multivariate odds ratio 0.77, 95% confidence interval 0.61-0.96, P=.02) and a decrease in Standardized Total Average Toxicity scores (−0.08, 95% confidence interval −0.15 to −0.02, P=.016). Conclusions: Using a stage design with replication, we identified a variant allele in the base excision repair gene XRCC1 that could be used in combination with additional variants for developing a test to predict late toxicities after radiation therapy in breast cancer patients.

XRCC1 Polymorphism Associated With Late Toxicity After Radiation Therapy in Breast Cancer Patients

International Nuclear Information System (INIS)

Seibold, Petra; Behrens, Sabine; Schmezer, Peter; Helmbold, Irmgard; Barnett, Gillian; Coles, Charlotte; Yarnold, John; Talbot, Christopher J.; Imai, Takashi; Azria, David; Koch, C. Anne; Dunning, Alison M.; Burnet, Neil; Bliss, Judith M.; Symonds, R. Paul; Rattay, Tim; Suga, Tomo; Kerns, Sarah L.

2015-01-01

Purpose: To identify single-nucleotide polymorphisms (SNPs) in oxidative stress–related genes associated with risk of late toxicities in breast cancer patients receiving radiation therapy. Methods and Materials: Using a 2-stage design, 305 SNPs in 59 candidate genes were investigated in the discovery phase in 753 breast cancer patients from 2 prospective cohorts from Germany. The 10 most promising SNPs in 4 genes were evaluated in the replication phase in up to 1883 breast cancer patients from 6 cohorts identified through the Radiogenomics Consortium. Outcomes of interest were late skin toxicity and fibrosis of the breast, as well as an overall toxicity score (Standardized Total Average Toxicity). Multivariable logistic and linear regression models were used to assess associations between SNPs and late toxicity. A meta-analysis approach was used to summarize evidence. Results: The association of a genetic variant in the base excision repair gene XRCC1, rs2682585, with normal tissue late radiation toxicity was replicated in all tested studies. In the combined analysis of discovery and replication cohorts, carrying the rare allele was associated with a significantly lower risk of skin toxicities (multivariate odds ratio 0.77, 95% confidence interval 0.61-0.96, P=.02) and a decrease in Standardized Total Average Toxicity scores (−0.08, 95% confidence interval −0.15 to −0.02, P=.016). Conclusions: Using a stage design with replication, we identified a variant allele in the base excision repair gene XRCC1 that could be used in combination with additional variants for developing a test to predict late toxicities after radiation therapy in breast cancer patients

Primary Radiation Therapy in Patients With Localized Orbital Marginal Zone B-Cell Lymphoma of Mucosa-Associated Lymphoid Tissue (MALT Lymphoma)

International Nuclear Information System (INIS)

Son, Seok Hyun; Choi, Byung Ock; Kim, Gi Won; Yang, Suk Woo; Hong, Young Seon; Choi, Ihl Bohng; Kim, Yeon Sil

2010-01-01

Purpose: To evaluate the outcomes of patients with localized orbital marginal zone B-cell lymphoma of the mucosa-associated lymphoid tissue (MALT lymphoma) who were treated with radiotherapy (RT). Methods and Materials: We retrospectively reviewed the records of 46 patients who were treated with RT for pathologically confirmed localized stage IE marginal zone B-cell lymphoma of MALT. The radiation dose ranged from 21.6 to 45 Gy (median, 30.6 Gy) at 1.8-2.0 Gy per fraction. Median follow-up duration was 32.3 months (range, 3.1-113.6 months). Results: Forty-three patients (93%) achieved complete remission (CR), and three patients (7%) achieved partial remission (PR). Five-year relapse-free survival, cause-specific survival, and overall survival were 93%, 100%, and 100%, respectively. Among the patients with CR, two had recurrence at three sites. One patient relapsed locally and was successfully salvaged with reirradiation. The other patient relapsed in a distant site and was successfully treated with six cycles of CHOP chemotherapy. Late complications were noted in four patients. Two patients developed cataracts at 26 and 37 months after completion of RT. The other two patients developed nasolacrimal duct obstructions at 4 and 11 months after completion of RT. Conclusion: Our study showed that a modest dose of RT is an excellent treatment modality with low complication and recurrence rates. We suggest that a dose of 30.6 Gy is tolerable and sufficient for treating orbital MALT lymphoma. Even following recurrence, successful salvage is possible with RT or chemotherapy.

A unique mode of tissue oxygenation and the adaptive radiation of teleost fishes.

Science.gov (United States)

Randall, D J; Rummer, J L; Wilson, J M; Wang, S; Brauner, C J

2014-04-15

Teleost fishes constitute 95% of extant aquatic vertebrates, and we suggest that this is related in part to their unique mode of tissue oxygenation. We propose the following sequence of events in the evolution of their oxygen delivery system. First, loss of plasma-accessible carbonic anhydrase (CA) in the gill and venous circulations slowed the Jacobs-Stewart cycle and the transfer of acid between the plasma and the red blood cells (RBCs). This ameliorated the effects of a generalised acidosis (associated with an increased capacity for burst swimming) on haemoglobin (Hb)-O2 binding. Because RBC pH was uncoupled from plasma pH, the importance of Hb as a buffer was reduced. The decrease in buffering was mediated by a reduction in the number of histidine residues on the Hb molecule and resulted in enhanced coupling of O2 and CO2 transfer through the RBCs. In the absence of plasma CA, nearly all plasma bicarbonate ultimately dehydrated to CO2 occurred via the RBCs, and chloride/bicarbonate exchange was the rate-limiting step in CO2 excretion. This pattern of CO2 excretion across the gills resulted in disequilibrium states for CO2 hydration/dehydration reactions and thus elevated arterial and venous plasma bicarbonate levels. Plasma-accessible CA embedded in arterial endothelia was retained, which eliminated the localized bicarbonate disequilibrium forming CO2 that then moved into the RBCs. Consequently, RBC pH decreased which, in conjunction with pH-sensitive Bohr/Root Hbs, elevated arterial oxygen tensions and thus enhanced tissue oxygenation. Counter-current arrangement of capillaries (retia) at the eye and later the swim bladder evolved along with the gas gland at the swim bladder. Both arrangements enhanced and magnified CO2 and acid production and, therefore, oxygen secretion to those specialised tissues. The evolution of β-adrenergically stimulated RBC Na(+)/H(+) exchange protected gill O2 uptake during stress and further augmented plasma disequilibrium states

Radiation-induced changes in production of prostaglandins Fsub(2. cap alpha. ), E, and thromboxane B/sub 2/ in guinea pig parenchymal lung tissues

Energy Technology Data Exchange (ETDEWEB)

Steel, L K; Catravas, G N [Armed Forces Radiobiology Research Inst., Bethesda, MD (USA)

1982-11-01

At 1 hour to 4 days after unilateral exposure of guinea pigs to a single dose (0.5, 1.5, or 3.0 Gy) of gamma-radiation, changes were detected in prostaglandin and thromboxane concentrations in parenchymal lung tissues. At 1-3 hours after exposure, tissue levels of PGFsub(2..cap alpha..), PGE, and thromboxane B/sub 2/ were significantly elevated in animals receiving 3.0 Gy, with the magnitude of alteration revealing a radiation dose effect. By 24 hours, tissue prostaglandin and thromboxane levels returned to near control values. Lung tissue synthesis of prostaglandins in response to H-1 receptor stimulation by the exogenous addition of histamine revealed similar radiation dose effects. The carboxylic acid ionophore A23187, exogenously applied to lung tissues, revealed a transient peak of increased sensitivity to ionophore stimulation for TxB/sub 2/ synthesis at 24 hours and for PGFsub(2..cap alpha..) at 72 hours post-irradiation. The data suggest that significant alterations in prostaglandin and thromboxane concentrations in parenchymal lung tissues occur following irradiation, in a dose-dependent manner, and that altered responsiveness to H-1 receptor stimulation and divalent cation transport also occur.

Radiation recall cutaneous induced by chlorambucil. Case report

International Nuclear Information System (INIS)

Dei-Cas, Ignacio; Wright, Dolores; Rigo, Bettina; Cohen Sabban, Emilia; Lacasagne, Jorgelina; Pietropaolo, Nelida; Cabo, Horacio; Molina, Malena

2005-01-01

Radiation recall refers to a tissue reaction produced by the use of certain drugs, usually chemotherapeutic agents, in a previously irradiated area. We report a patient with cutaneous radiation recall associated with chlorambucil, drug previously unreported as a causative agent in the literature. (author) [es

INTERACTION OF LASER RADIATION WITH MATTER: Calculation of the kinetics of heating and structural changes in the cartilaginous tissue under the action of laser radiation

Science.gov (United States)

Sobol', E. N.; Kitai, M. S.

1998-07-01

A theoretical model is developed for the calculation of the temperature fields and determination of the size of a zone with structural changes in the cartilaginous tissue. The model is based on a simultaneous analysis of the heat and mass transfer processes and it takes into account the bulk absorption of laser radiation by the tissue, surface evaporation of water, and temperature dependences of the diffusion coefficients. It is assumed that under the influence of a phase transition between free and bound water, caused by heating of the cartilage to 70°C, the proteoglycans of the cartilage matrix become mobile and, as a result of such mass transfer, structural changes are induced in the cartilaginous tissue causing relaxation of stresses or denaturation. It is shown that the maximum temperature is then reached not on the irradiated surface but at some distance from it, and that the size of the zones of structural changes (denaturation depth) depends strongly on the energy density of the laser radiation and its wavelength, on the duration of the irradiation, and on the cartilage thickness. This model makes it possible to calculate the temperature fields and the depth of structural changes in laser-induced relaxation of stresses and changes in the shape of the cartilaginous tissue.

Minimising the risk: reducing breast tissue dose in an adolescent female

International Nuclear Information System (INIS)

Thompson, Ann; Toe, Aimee; Ungureanu, Elena; Wolf, M.; Wirth, Andrew

2005-01-01

Breast cancer is amongst the leading radiation-associated, second malignancies that develop in patients after treatment for Hodgkin's disease. This risk is affected by two main factors: 1. The age of the patient at the time of radiotherapy; and 2. The dose received by the breast tissue The adolescent female thus faces an exceptionally high risk, as breast tissue at this age is undergoing rapid developmental growth and small doses of radiation exposure could be carcinogenic. This case report of a fifteen-year-old girl who received radiotherapy for Hodgkin's disease demonstrates how radiation therapists worked together with the radiation oncologists and medical physicists to provide an optimal treatment plan for a high-risk patient. Copyright (2005) Australian Institute of Radiography

Radiation and Homeostasis

International Nuclear Information System (INIS)

Sugahara, T.; Nikaido, O.; Niwa, O.

2002-01-01

These proceedings aim to promote the understanding of the health hazard of radiation at low dose range and to construct a more solid basis for radiation safety policy. Radiation hazard has been the central issue of investigation in the field of radiation research. The two major approaches are mechanistic analysis by laboratory investigation and phenomenological analysis of radiation-exposed population as represented by epidemiology. In an increasingly safety-conscious society, the extremely low level risk associated with low dose of radiation has become an important issue. In this area, the phenomenological approach has a limit. DNA damage is the primary and direct cause of the risk. Tremendous progress has been made recently in the basic understanding of radiation effects on cells and tissues and the importance of damage response rather than damage itself. This challenges the classical linear non-threshold hypothesis

Importance of scatter compensation algorithm in heterogeneous tissue for the radiation dose calculation of small lung nodules. A clinical study

International Nuclear Information System (INIS)

Baba, Yuji; Murakami, Ryuji; Mizukami, Naohisa; Morishita, Shoji; Yamashita, Yasuyuki; Araki, Fujio; Moribe, Nobuyuki; Hirata, Yukinori

2004-01-01

The purpose of this study was to compare radiation doses of small lung nodules calculated with beam scattering compensation and those without compensation in heterogeneous tissues. Computed tomography (CT) data of 34 small (1-2 cm: 12 nodules, 2-3 cm 11 nodules, 3-4 cm 11 nodules) lung nodules were used in the radiation dose measurements. Radiation planning for lung nodule was performed with a commercially available unit using two different radiation dose calculation methods: the superposition method (with scatter compensation in heterogeneous tissues), and the Clarkson method (without scatter compensation in heterogeneous tissues). The energy of the linac photon used in this study was 10 MV and 4 MV. Monitor unit (MU) to deliver 10 Gy at the center of the radiation field (center of the nodule) calculated with the two methods were compared. In 1-2 cm nodules, MU calculated by Clarkson method (MUc) was 90.0±1.1% (4 MV photon) and 80.5±2.7% (10 MV photon) compared to MU calculated by superposion method (MUs), in 2-3 cm nodules, MUc was 92.9±1.1% (4 MV photon) and 86.6±2.8% (10 MV photon) compared to MUs, and in 3-4 cm nodules, MUc was 90.5±2.0% (4 MV photon) and 90.1±1.7% (10 MV photon) compared to MUs. In 1-2 cm nodules, MU calculated without lung compensation (MUn) was 120.6±8.3% (4 MV photon) and 95.1±4.1% (10 MV photon) compared to MU calculated by superposion method (MUs), in 2-3 cm nodules, MUc was 120.3±11.5% (4 MV photon) and 100.5±4.6% (10 MV photon) compared to MUs, and in 3-4 cm nodules, MUc was 105.3±9.0% (4 MV photon) and 103.4±4.9% (10 MV photon) compared to MUs. The MU calculated without lung compensation was not significantly different from the MU calculated by superposition method in 2-3 cm nodules. We found that the conventional dose calculation algorithm without scatter compensation in heterogeneous tissues substantially overestimated the radiation dose of small nodules in the lung field. In the calculation of dose distribution of small

Calculation of the kinetics of heating and structural changes in the cartilaginous tissue under the action of laser radiation

International Nuclear Information System (INIS)

Sobol', E N; Kitai, M S

1998-01-01

A theoretical model is developed for the calculation of the temperature fields and determination of the size of a zone with structural changes in the cartilaginous tissue. The model is based on a simultaneous analysis of the heat and mass transfer processes and it takes into account the bulk absorption of laser radiation by the tissue, surface evaporation of water, and temperature dependences of the diffusion coefficients. It is assumed that under the influence of a phase transition between free and bound water, caused by heating of the cartilage to 70 0 C, the proteoglycans of the cartilage matrix become mobile and, as a result of such mass transfer, structural changes are induced in the cartilaginous tissue causing relaxation of stresses or denaturation. It is shown that the maximum temperature is then reached not on the irradiated surface but at some distance from it, and that the size of the zones of structural changes (denaturation depth) depends strongly on the energy density of the laser radiation and its wavelength, on the duration of the irradiation, and on the cartilage thickness. This model makes it possible to calculate the temperature fields and the depth of structural changes in laser-induced relaxation of stresses and changes in the shape of the cartilaginous tissue. (interaction of laser radiation with matter)

The tolerance of skin grafts to postoperative radiation therapy in patients with soft-tissue sarcoma

International Nuclear Information System (INIS)

Lawrence, W.T.; Zabell, A.; McDonald, H.D.

1986-01-01

During the last ten years at the National Cancer Institute, 11 patients have received 12 courses of postoperative adjuvant radiation therapy to skin grafts used for wound closure after the resection of soft-tissue sarcomas. The intervals between grafting and the initiation of radiation ranged between 3 and 20 weeks, and 4 patients received chemotherapy at the same time as their radiation. Ten of the 12 irradiated grafts remained intact after the completion of therapy. One graft had several small persistently ulcerated areas that required no further surgical treatment, and one graft required a musculocutaneous flap for reconstruction of a persistent large ulcer. Acute radiation effects on the grafted skin sometimes developed at slightly lower doses than usually seen with normal skin, but these acute effects necessitated a break in therapy on only five occasions. Concurrent chemotherapy and a relatively short interval between grafting and the initiation of radiation seemed to contribute to more severe radiation reactions. This experience indicates that postoperative adjuvant radiation therapy can be delivered to skin grafted areas without undue fear of complications, especially if the graft is allowed to heal adequately prior to initiating therapy and if chemotherapy is not given in conjunction with radiation

Association between increased epicardial adipose tissue volume and coronary plaque composition.

Science.gov (United States)

Yamashita, Kennosuke; Yamamoto, Myong Hwa; Ebara, Seitarou; Okabe, Toshitaka; Saito, Shigeo; Hoshimoto, Koichi; Yakushiji, Tadayuki; Isomura, Naoei; Araki, Hiroshi; Obara, Chiaki; Ochiai, Masahiko

2014-09-01

To assess the relationship between epicardial adipose tissue volume (EATV) and plaque vulnerability in significant coronary stenosis using a 40-MHz intravascular ultrasound (IVUS) imaging system (iMap-IVUS), we analyzed 130 consecutive patients with coronary stenosis who underwent dual-source computed tomography (CT) and cardiac catheterization. Culprit lesions were imaged by iMap-IVUS before stenting. The iMAP-IVUS system classified coronary plaque components as fibrous, lipid, necrotic, or calcified tissue, based on the radiofrequency spectrum. Epicardial adipose tissue was measured as the tissue ranging from -190 to -30 Hounsfield units. EATV, calculated as the sum of the fat areas on short-axis images, was 85.0 ± 34.0 cm(3). There was a positive correlation between EATV and the percentage of necrotic plaque tissue (R (2) = 0.34, P EATV and the percentage of fibrous tissue (R (2) = 0.24, P EATV (β = 0.14, P = 0.02) were independently associated with the percentage of necrotic plaque tissue. An increase in EATV was associated with the development of coronary atherosclerosis and, potentially, with the most dangerous type of plaque.

Preliminary study of human breast tissue using synchrotron radiation combining WAXS and SAXS techniques

International Nuclear Information System (INIS)

Conceicao, A.L.C.; Antoniassi, M.; Poletti, M.E.; Caldas, L.V.E.

2010-01-01

Using synchrotron radiation, we combined simultaneously wide angle X-ray scattering (WAXS) and small angle X-ray scattering (SAXS) techniques to obtain the scattering profiles of normal and neoplastic breast tissues samples at the momentum transfer range 6.28 nm -1 ≤Q(=4π.sin(θ/2)/λ)≤50.26 nm -1 and 0.15 nm -1 ≤Q≤1.90 nm -1 , respectively. The results obtained show considerable differences between the scattering profiles of these tissues. We verified that the combination of some parameters (ratio between glandular and adipose peak intensity and third-order axial peak intensity) extracted from scattering profiles can be used for identifying breast cancer.

Association between plasma metabolites and gene expression profiles in five porcine endocrine tissues

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Bassols Anna

2011-07-01

Full Text Available Abstract Background Endocrine tissues play a fundamental role in maintaining homeostasis of plasma metabolites such as non-esterified fatty acids and glucose, the levels of which reflect the energy balance or the health status of animals. However, the relationship between the transcriptome of endocrine tissues and plasma metabolites has been poorly studied. Methods We determined the blood levels of 12 plasma metabolites in 27 pigs belonging to five breeds, each breed consisting of both females and males. The transcriptome of five endocrine tissues i.e. hypothalamus, adenohypophysis, thyroid gland, gonads and backfat tissues from 16 out of the 27 pigs was also determined. Sex and breed effects on the 12 plasma metabolites were investigated and associations between genes expressed in the five endocrine tissues and the 12 plasma metabolites measured were analyzed. A probeset was defined as a quantitative trait transcript (QTT when its association with a particular metabolic trait achieved a nominal P value Results A larger than expected number of QTT was found for non-esterified fatty acids and alanine aminotransferase in at least two tissues. The associations were highly tissue-specific. The QTT within the tissues were divided into co-expression network modules enriched for genes in Kyoto Encyclopedia of Genes and Genomes or gene ontology categories that are related to the physiological functions of the corresponding tissues. We also explored a multi-tissue co-expression network using QTT for non-esterified fatty acids from the five tissues and found that a module, enriched in hypothalamus QTT, was positioned at the centre of the entire multi-tissue network. Conclusions These results emphasize the relationships between endocrine tissues and plasma metabolites in terms of gene expression. Highly tissue-specific association patterns suggest that candidate genes or gene pathways should be investigated in the context of specific tissues.

The International radiation protection association (IRPA) 2010-2011 strategic plan

International Nuclear Information System (INIS)

Kase, K.

2010-01-01

The membership of IRPA consists of 46 national or regional associate societies, 58 countries and about 17,000 individual members. The goals of IRPA strategic Plan 2008-2012 are: Promote excellence in the conduct of IRPA Promote excellence in national and regional associate societies Promote excellence in radiation protection professionals IRPA is recognized by its members and stakeholders as the international voice of the radiation protection profession. The role of IRPA is to: Provide a medium for communication and advancement of radiation protection throughout the world Encourage the establishment of radiation protection societies Support international meetings Encourage international publications dedicated to radiation protection Encourage the establishment and continuous review of universally acceptable radiation protection standards and recommendations Encourage professional enhancement

Tobacco Smoking During Radiation Therapy for Head-and-Neck Cancer Is Associated With Unfavorable Outcome

International Nuclear Information System (INIS)

Chen, Allen M.; Chen, Leon M.; Vaughan, Andrew; Sreeraman, Radhika; Farwell, D. Gregory; Luu, Quang; Lau, Derick H.; Stuart, Kerri; Purdy, James A.; Vijayakumar, Srinivasan

2011-01-01

Purpose: To evaluate the effect of continued cigarette smoking among patients undergoing radiation therapy for head-and-neck cancer by comparing the clinical outcomes among active smokers and quitters. Methods and Materials: A review of medical records identified 101 patients with newly diagnosed squamous cell carcinoma of the head and neck who continued to smoke during radiation therapy. Each active smoker was matched to a control patient who had quit smoking before initiation of radiation therapy. Matching was based on tobacco history (pack-years), primary site, age, sex, Karnofsky Performance Status, disease stage, radiation dose, chemotherapy use, year of treatment, and whether surgical resection was performed. Outcomes were compared by use of Kaplan-Meier analysis. Normal tissue effects were graded according to the Radiation Therapy Oncology Group/European Organization for the Treatment of Cancer toxicity criteria. Results: With a median follow-up of 49 months, active smokers had significantly inferior 5-year overall survival (23% vs. 55%), locoregional control (58% vs. 69%), and disease-free survival (42% vs. 65%) compared with the former smokers who had quit before radiation therapy (p < 0.05 for all). These differences remained statistically significant when patients treated by postoperative or definitive radiation therapy were analyzed separately. The incidence of Grade 3 or greater late complications was also significantly increased among active smokers compared with former smokers (49% vs. 31%, p = 0.01). Conclusions: Tobacco smoking during radiation therapy for head-and-neck cancer is associated with unfavorable outcomes. Further studies analyzing the biologic and molecular reasons underlying these differences are planned.

Radiogenomics: predicting clinical normal tissue radiosensitivity

DEFF Research Database (Denmark)

Alsner, Jan

2006-01-01

Studies on the genetic basis of normal tissue radiosensitivity, or  'radiogenomics', aims at predicting clinical radiosensitivity and optimize treatment from individual genetic profiles. Several studies have now reported links between variations in certain genes related to the biological response...... to radiation injury and risk of normal tissue morbidity in cancer patients treated with radiotherapy. However, after these initial association studies including few genes, we are still far from being able to predict clinical radiosensitivity on an individual level. Recent data from our own studies on risk...

Identifying and exploiting trait-relevant tissues with multiple functional annotations in genome-wide association studies

Science.gov (United States)

Zhang, Shujun

2018-01-01

Genome-wide association studies (GWASs) have identified many disease associated loci, the majority of which have unknown biological functions. Understanding the mechanism underlying trait associations requires identifying trait-relevant tissues and investigating associations in a trait-specific fashion. Here, we extend the widely used linear mixed model to incorporate multiple SNP functional annotations from omics studies with GWAS summary statistics to facilitate the identification of trait-relevant tissues, with which to further construct powerful association tests. Specifically, we rely on a generalized estimating equation based algorithm for parameter inference, a mixture modeling framework for trait-tissue relevance classification, and a weighted sequence kernel association test constructed based on the identified trait-relevant tissues for powerful association analysis. We refer to our analytic procedure as the Scalable Multiple Annotation integration for trait-Relevant Tissue identification and usage (SMART). With extensive simulations, we show how our method can make use of multiple complementary annotations to improve the accuracy for identifying trait-relevant tissues. In addition, our procedure allows us to make use of the inferred trait-relevant tissues, for the first time, to construct more powerful SNP set tests. We apply our method for an in-depth analysis of 43 traits from 28 GWASs using tissue-specific annotations in 105 tissues derived from ENCODE and Roadmap. Our results reveal new trait-tissue relevance, pinpoint important annotations that are informative of trait-tissue relationship, and illustrate how we can use the inferred trait-relevant tissues to construct more powerful association tests in the Wellcome trust case control consortium study. PMID:29377896

Identifying and exploiting trait-relevant tissues with multiple functional annotations in genome-wide association studies.

Directory of Open Access Journals (Sweden)

Xingjie Hao

2018-01-01

Full Text Available Genome-wide association studies (GWASs have identified many disease associated loci, the majority of which have unknown biological functions. Understanding the mechanism underlying trait associations requires identifying trait-relevant tissues and investigating associations in a trait-specific fashion. Here, we extend the widely used linear mixed model to incorporate multiple SNP functional annotations from omics studies with GWAS summary statistics to facilitate the identification of trait-relevant tissues, with which to further construct powerful association tests. Specifically, we rely on a generalized estimating equation based algorithm for parameter inference, a mixture modeling framework for trait-tissue relevance classification, and a weighted sequence kernel association test constructed based on the identified trait-relevant tissues for powerful association analysis. We refer to our analytic procedure as the Scalable Multiple Annotation integration for trait-Relevant Tissue identification and usage (SMART. With extensive simulations, we show how our method can make use of multiple complementary annotations to improve the accuracy for identifying trait-relevant tissues. In addition, our procedure allows us to make use of the inferred trait-relevant tissues, for the first time, to construct more powerful SNP set tests. We apply our method for an in-depth analysis of 43 traits from 28 GWASs using tissue-specific annotations in 105 tissues derived from ENCODE and Roadmap. Our results reveal new trait-tissue relevance, pinpoint important annotations that are informative of trait-tissue relationship, and illustrate how we can use the inferred trait-relevant tissues to construct more powerful association tests in the Wellcome trust case control consortium study.

Electrical impedance along connective tissue planes associated with acupuncture meridians

Directory of Open Access Journals (Sweden)

Hammerschlag Richard

2005-05-01

Full Text Available Abstract Background Acupuncture points and meridians are commonly believed to possess unique electrical properties. The experimental support for this claim is limited given the technical and methodological shortcomings of prior studies. Recent studies indicate a correspondence between acupuncture meridians and connective tissue planes. We hypothesized that segments of acupuncture meridians that are associated with loose connective tissue planes (between muscles or between muscle and bone visible by ultrasound have greater electrical conductance (less electrical impedance than non-meridian, parallel control segments. Methods We used a four-electrode method to measure the electrical impedance along segments of the Pericardium and Spleen meridians and corresponding parallel control segments in 23 human subjects. Meridian segments were determined by palpation and proportional measurements. Connective tissue planes underlying those segments were imaged with an ultrasound scanner. Along each meridian segment, four gold-plated needles were inserted along a straight line and used as electrodes. A parallel series of four control needles were placed 0.8 cm medial to the meridian needles. For each set of four needles, a 3.3 kHz alternating (AC constant amplitude current was introduced at three different amplitudes (20, 40, and 80 μAmps to the outer two needles, while the voltage was measured between the inner two needles. Tissue impedance between the two inner needles was calculated based on Ohm's law (ratio of voltage to current intensity. Results At the Pericardium location, mean tissue impedance was significantly lower at meridian segments (70.4 ± 5.7 Ω compared with control segments (75.0 ± 5.9 Ω (p = 0.0003. At the Spleen location, mean impedance for meridian (67.8 ± 6.8 Ω and control segments (68.5 ± 7.5 Ω were not significantly different (p = 0.70. Conclusion Tissue impedance was on average lower along the Pericardium meridian, but not

Basic research on cancer related to radiation associated medical researches

International Nuclear Information System (INIS)

Lee, Jong In; Hwang, Dae Yong; Bang, Ho Yoon

2000-12-01

Basic Research on Cancer related to Radiation Associated Medical Researches including 1. Establishment of animal model of colorectal cancer liver metastasis and measurement of angiogenesis, 2. Tissue expression of Tie-1 and Tie-2 in human colorectal cancer, 3. Enhancement of G2/Mphase Cell Fraction by Adenovirus-mediated p53 Gene Transfer in Ovarian Cancer Cell Lines, 4. Clinical Characteristics of the patients with Non-B Non-C Hepatocellular Carcinoma and Frequency of HBV, HCV and TTV Viremia in these Patients, 5. Significance of serum iron and ferritin in patients with stomach cancer, 6. Telomerase assay for early detection of lung cancer, 7. Study on the Usefulness of Aldehyde dehydrogenase-2 Genotyping for Risk Group of Alcohol-related Cancer Screening, 8. Gene therapy using hepatoma specific promoter, 9. Study on the Influence of DNA repair gene, XRCC1 Genotypes on the Risk of Head and Neck Cancer were performed

Basic research on cancer related to radiation associated medical researches

Energy Technology Data Exchange (ETDEWEB)

Lee, Jong In; Hwang, Dae Yong; Bang, Ho Yoon [and others

2000-12-01

Basic Research on Cancer related to Radiation Associated Medical Researches including 1. Establishment of animal model of colorectal cancer liver metastasis and measurement of angiogenesis, 2. Tissue expression of Tie-1 and Tie-2 in human colorectal cancer, 3. Enhancement of G2/Mphase Cell Fraction by Adenovirus-mediated p53 Gene Transfer in Ovarian Cancer Cell Lines, 4. Clinical Characteristics of the patients with Non-B Non-C Hepatocellular Carcinoma and Frequency of HBV, HCV and TTV Viremia in these Patients, 5. Significance of serum iron and ferritin in patients with stomach cancer, 6. Telomerase assay for early detection of lung cancer, 7. Study on the Usefulness of Aldehyde dehydrogenase-2 Genotyping for Risk Group of Alcohol-related Cancer Screening, 8. Gene therapy using hepatoma specific promoter, 9. Study on the Influence of DNA repair gene, XRCC1 Genotypes on the Risk of Head and Neck Cancer were performed.

An experimental study on the radiation-induced injury of the rabbit lung: Correlation of soft-tissue radiograph and high- resolution CT findings with pathologic findings

International Nuclear Information System (INIS)

Lee, Ki Nam; Nam, Kyung Jin; Park, Byeoung Ho; Jeong, Jin Sook; Lee, Hyung Sik

1994-01-01

To describe soft-tissue radiographic and high-resolution CT findings of radiation-induced lung injury of rabbit over time and to correlate them with pathologic findings. 15 rabbits were irradiated in the right lung with one fracture of 2000 cGy. After 4, 6, 12, 20, 24 weeks 3 rabbits in each group were sacrificed and soft-tissue radiographs and high-resolution CT of their lung tissue were obtained. Radiological findings were correlated with pathologic findings. On soft-tissue radiogram, radiation pneumonitis shown as consolidation with air- bronchogram occurred in 3 cases after 6 weeks , and in 1 case after 12 weeks of irradiation. In addition, pneumonic consolidation with adjacent pleural contraction was seen in 2 cases after 12 weeks of irradiation. Fibrotic changes indicated by decreased volume occurred after 20 weeks and combined bronchiectatic change and bronchial wall thickening appeared after 20 weeks(N=1), and 24 weeks(N=3). HRCT findings of radiation pneumonitis were homogeneous, increased attention after 4 weeks(N=3), 6 and 12 weeks(each N=1), patchy consolidation after 6 and 12 weeks(each N=2), discrete consolidation after 12, 20 and 24 weeks(each N=1) and solid consolidation after 20 and 24 weeks(each N=2). Pathologically radiation pneumonitis and pulmonary congestion were seen after 4 and 6 weeks. After 6 weeks, collagen and reticulin fibers were detected along alveolar wall. Mixed radiation pneumonitis and fibrosis were detected after 12 weeks. 20 weeks after irradiation, fibrosis was well defined in interstitium and in 24 weeks, decreased number of alveoli and thickening of bronchial wall were defined. Radiation pneumonitis was provoked 4 weeks after irradiation on rabbit lung and progressed into radiation fibrosis 20 weeks after irradiation on soft-tissue radiographs and high-resolution CT. High-resolution CT is more precise in detecting early radiation pneumonitis and detailed pathologic findings

Radiation risk of tissue late effects, a net consequence of probabilities of various cellular responses

International Nuclear Information System (INIS)

Feinendegen, L.E.

1991-01-01

Late effects from the exposure to low doses of ionizing radiation are hardly or not at all observed in man mainly due to the low values of risk coefficients that preclude statistical analyses of data from populations that are exposed to doses less than 0.2 Gy. In order to arrive at an assessment of potential risk from radiation exposure in the low dose range, the microdosimetry approach is essential. In the low dose range, ionizing radiation generates particle tracks, mainly electrons, which are distributed rather heterogeneously within the exposed tissue. Taking the individual cell as the elemental unit of life, observations and calculations of cellular responses to being hit by energy depositions events from low LET type are analysed. It emerges that besides the probability of a hit cell to sustain a detrimental effect with the consequense of malignant transformation there are probabilities of various adaptive responses that equipp the hit cell with a benefit. On the one hand, an improvement of cellular radical detoxification was observed in mouse bone marrow cells; another adaptive response pertaining to improved DNA repair, was reported for human lymphocytes. The improved radical detoxification in mouse bone marrow cells lasts for a period of 5-10 hours and improved DNA repair in human lymphocytes was seen for some 60 hours following acute irradiation. It is speculated that improved radical detoxification and improved DNA repair may reduce the probability of spontaneous carcinogenesis. Thus it is proposed to weigh the probability of detriment for a hit cell within a multicellular system against the probability of benefit through adaptive responses in other hit cells in the same system per radiation exposure. In doing this, the net effect of low doses of low LET radiation in tissue with individual cells being hit by energy deposition events could be zero or even beneficial. (orig./MG)

In situ biological dose mapping estimates the radiation burden delivered to 'spared' tissue between synchrotron X-ray microbeam radiotherapy tracks.

Directory of Open Access Journals (Sweden)

Kai Rothkamm

Full Text Available Microbeam radiation therapy (MRT using high doses of synchrotron X-rays can destroy tumours in animal models whilst causing little damage to normal tissues. Determining the spatial distribution of radiation doses delivered during MRT at a microscopic scale is a major challenge. Film and semiconductor dosimetry as well as Monte Carlo methods struggle to provide accurate estimates of dose profiles and peak-to-valley dose ratios at the position of the targeted and traversed tissues whose biological responses determine treatment outcome. The purpose of this study was to utilise γ-H2AX immunostaining as a biodosimetric tool that enables in situ biological dose mapping within an irradiated tissue to provide direct biological evidence for the scale of the radiation burden to 'spared' tissue regions between MRT tracks. Γ-H2AX analysis allowed microbeams to be traced and DNA damage foci to be quantified in valleys between beams following MRT treatment of fibroblast cultures and murine skin where foci yields per unit dose were approximately five-fold lower than in fibroblast cultures. Foci levels in cells located in valleys were compared with calibration curves using known broadbeam synchrotron X-ray doses to generate spatial dose profiles and calculate peak-to-valley dose ratios of 30-40 for cell cultures and approximately 60 for murine skin, consistent with the range obtained with conventional dosimetry methods. This biological dose mapping approach could find several applications both in optimising MRT or other radiotherapeutic treatments and in estimating localised doses following accidental radiation exposure using skin punch biopsies.

Challenges in Regulating Radiation Sources and Associated Waste Management

International Nuclear Information System (INIS)

Shehzad, A.

2016-01-01

Radiation sources are widely used in the fields of medical, industry, agriculture, research, etc. Owing to the inherent risk of exposure to ionizing radiations while using the radiation sources and management of associated waste, safety measures are of utmost importance including robust regulatory control. Pakistan Nuclear Regulatory Authority (PNRA) is responsible for supervising all matters pertaining to nuclear safety and radiation protection in the country. Since its inception, PNRA has made rigorous efforts to regulate the radiation facilities for which regulatory framework was further strengthened by taking into account international norms/practices and implemented afterwards. However, due to vibrant use of these facilities, there are numerous challenges being faced while implementing the regulatory framework. These challenges pertains to shielding design of some facilities, control over service provider for QC/repair maintenance of radiation equipment, assessment of patient doses, and establishment of national diagnostic reference levels for radiological procedures. Further, the regulatory framework also delineate requirements to minimize the generation of associated radioactive waste as low as practicable. The requirements also necessitates that certain sealed radioactive sources (SRS) are returned to the supplier upon completion of their useful life, while other radioactive sources are required to be transported for storage at designated radioactive waste storage facilities in the country, which requires commitment from the licensee. This paper will briefly describe the challenges in regulating the radiation sources and issues related to the waste management associated with these facilities. (author)

Determination of effective atomic number of breast tissues using scattered radiation; Determinacao do numero atomico efetivo de tecidos mamarios usando a radiacao espalhada

Energy Technology Data Exchange (ETDEWEB)

Antoniassi, M.; Conceicao, A.L.C.; Poletti, M.E. [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil). Fac. de Filosofia, Ciencias e Letras. Dept. de Fisica e Matematica

2010-07-01

The scattered radiation has been used in several industrial and clinical applications since it permits to characterize the scattering material. Several types of information can be extracted from the spectrum of scattered radiation which can be used to characterization of biological tissues such as breast tissues. In this work we have measured Compton and Rayleigh scattering radiation from normal (adipose), benign (fibroadenoma) and malignant (carcinoma) neoplastic breast tissues using a monoenergetic beam of 17.44 keV and a scattering angle of 90 deg C (x = 0.99 angstrom-1). A practical method using the area of elastic and inelastic scattering was used for determining the effective atomic number (Z{sub eff}) of the samples, being validated comparing the experimental obtained values of Z{sub eff} of several standard materials with calculated values using traditional method based on total cross-section of compounds. The obtained results show that exist differences in the distributions of Z{sub eff} of breast tissues, which are related to the content of carbon (Z=6) and oxygen (Z=8) in each tissue type. The results suggest that is possible to use this parameter for characterizing breast tissues, pointing the possibility of its use as a complementary tool for the diagnosis of the breast cancer. (author)

Radiation protection instruments based on tissue equivalent proportional counters: Part II of an international intercomparison

International Nuclear Information System (INIS)

Alberts, W.G.; Dietz, E.; Guldbakke, S.; Kluge, H.; Schumacher, H.

1988-04-01

This report describes the irradiation conditions and procedures of Part II of an international intercomparison of tissue-equivalent proportional counters used for radiation protection measurements. The irradiations took place in monoenergetic reference neutron fields produced by the research reactor and accelerator facilities of the PTB Braunschweig in the range from thermal neutrons to 14.8 MeV. In addition measurements were performed in 60 Co and D 2 O-moderated 252 Cf radiation fields. Prototype instruments from 7 European groups were investigated. The results of the measurements are summarized and compared with the reference data of the irradiations. (orig.) [de

Can cell survival parameters be deduced from non-clonogenic assays of radiation damage to normal tissue

International Nuclear Information System (INIS)

Michalowski, A.; Wheldon, T.E.; Kirk, J.

1984-01-01

The relationship between dose-response curves for large scale radiation injury to tissues and survival curves for clonogenic cells is not necessarily simple. Sterilization of clonogenic cells occurs near-instantaneously compared with the protracted lag period for gross injury to tissues. Moreover, with some types of macroscopic damage, the shapes of the dose-response curves may depend on time of assay. Changes in the area or volume of irradiated tissue may also influence the shapes of these curves. The temporal pattern of expression of large scale injury also varies between tissues, and two distinct groups can be recognized. In rapidly proliferating tissues, lag period is almost independent of dose, whilst in slowly proliferating tissues, it is inversely proportional to dose. This might be explained by invoking differences in corresponding proliferative structures of the tissues. (Three compartmental Type H versus one compartmental Type F proliferative organization). For the second group of tissues particularly, mathematical modelling suggests a systematic dissociation of the dose-response curves for clonogenic cell survival and large scale injury. In particular, it may be difficult to disentangle the contributions made to inter-fraction sparing by cellular repair processes and by proliferation-related factors. (U.K.)

Relation between radiation-induced tissue injury and its carcinogenesis of the rat small intestine

Energy Technology Data Exchange (ETDEWEB)

Tsubouchi, S [Aichi Cancer Center, Nagoya (Japan). Research Inst.; Matsuzawa, T

1975-06-01

This study was undertaken to make clear the relationships between radiation-induced tissue injury and its carcinogenesis in the rat small intestine. The abdomens of Wistar rats were irradiated locally with 1000 to 2000 rads. Approximately 2 months following irradiation, visible nodules were found in the intestines of the groups receiving irradiation. Nodule incidence was 80 to 100% in groups that received 1750 or 2000 rads, 50% in the 1500-rad groups, and 3% in the 1000-rad groups, respectively. The histology of the nodules within 70 days postirradiation, revealed adenomatous hyperplasia, including invasion of submucosa, muscle layers, and serosa of the small intestine accompanied by an area of fibrous tissue resulting from desmoplastic reaction by irradiation injury. The nodule within 140 to 300 days postirradiation induced advanced tissue injuried, that is, a polypoid lesion in histology and intestinal nodular adhesion in macroscopic anatomy. Running parallel with the advance of the above mentioned tissue injuries, the nodules in 3 out of 18 rat during 200 to 300 days postirradiation showed mucoid adenocarcinoma.

Relation between radiation-induced tissue injury and its carcinogenesis of the rat small intestine

International Nuclear Information System (INIS)

Tsubouchi, Susumu; Matsuzawa, Taiju.

1975-01-01

This study was undertaken to make clear the relationships between radiation-induced tissue injury and its carcinogenesis in the rat small intestine. The abdomens of Wistar rats were irradiated locally with 1000 to 2000 rads. Approximately 2 months following irradiation, visible nodules were found in the intestines of the groups receiving irradiation. Nodule incidence was 80 to 100% in groups that received 1750 or 2000 rads, 50% in the 1500-rad groups, and 3% in the 1000-rad groups, respectively. The histology of the nodules within 70 days postirradiation, revealed adenomatous hyperplasia, including invasion of submucosa, muscle layers, and serosa of the small intestine accompanied by an area of fibrous tissue resulting from desmoplastic reaction by irradiation injury. The nodule within 140-300 days postirradiation induced advanced tissue injuried, that is, a polypoid lesion in histology and intestinal nodular adhesion in macroscopic anatomy. Running parallel with the advance of the above mentioned tissue injuries, the nodules in 3 out of 18 rat during 200-300 days postirradiation showed mucoid adenocarcinoma. (author)

Activation of vestibule-associated lymphoid tissue in localized provoked vulvodynia.

Science.gov (United States)

Tommola, Päivi; Bützow, Ralf; Unkila-Kallio, Leila; Paavonen, Jorma; Meri, Seppo

2015-04-01

Localized provoked vulvodynia (LPV) may have inflammatory etiology. We wanted to find out whether the cell-mediated immune system becomes activated in the vestibular mucosa in LPV. This was a controlled cross-sectional study. Vestibular mucosal specimens were obtained from 27 patients with severe LPV and 15 controls. Detailed clinical history of the patients was obtained. For immunohistochemistry, antibodies against CD3 (T cells), CD20 (B cells), IgA (mucosal plasma cells), CD163 (dendritic cells [DCs]), CD68 (macrophages), and CD117 (mast cells) were employed. Mann-Whitney U test and χ(2) test were used for statistical analyses. More B lymphocytes and mature mucosal IgA-plasma cells were found in patients than in controls (P associated lymphoid tissue analogous to mucosa-associated lymphoid tissue. Vestibule-associated lymphoid tissue may emerge as a response to local infection or inflammation in LPV. Copyright © 2015 Elsevier Inc. All rights reserved.

The effect of iodine uptake on radiation dose absorbed by patient tissues in contrast enhanced CT imaging. Implications for CT dosimetry

Energy Technology Data Exchange (ETDEWEB)

Perisinakis, Kostas; Damilakis, John [University of Crete, Department of Medical Physics, Medical School, Heraklion, Crete (Greece); University Hospital of Heraklion, Department of Medical Physics, Heraklion, Crete (Greece); Tzedakis, Antonis; Papadakis, Antonios E. [University Hospital of Heraklion, Department of Medical Physics, Heraklion, Crete (Greece); Spanakis, Kostas [University Hospital of Heraklion, Department of Radiology, Heraklion, Crete (Greece); Hatzidakis, Adam [University Hospital of Heraklion, Department of Radiology, Heraklion, Crete (Greece); University of Crete, Department of Radiology, Medical School, Heraklion, Crete (Greece)

2018-01-15

To investigate the effect of iodine uptake on tissue/organ absorbed doses from CT exposure and its implications in CT dosimetry. The contrast-induced CT number increase of several radiosensitive tissues was retrospectively determined in 120 CT examinations involving both non-enhanced and contrast-enhanced CT imaging. CT images of a phantom containing aqueous solutions of varying iodine concentration were obtained. Plots of the CT number increase against iodine concentration were produced. The clinically occurring iodine tissue uptake was quantified by attributing recorded CT number increase to a certain concentration of aqueous iodine solution. Clinically occurring iodine uptake was represented in mathematical anthropomorphic phantoms. Standard 120 kV CT exposures were simulated using Monte Carlo methods and resulting organ doses were derived for non-enhanced and iodine contrast-enhanced CT imaging. The mean iodine uptake range during contrast-enhanced CT imaging was found to be 0.02-0.46% w/w for the investigated tissues, while the maximum value recorded was 0.82% w/w. For the same CT exposure, iodinated tissues were found to receive higher radiation dose than non-iodinated tissues, with dose increase exceeding 100% for tissues with high iodine uptake. Administration of iodinated contrast medium considerably increases radiation dose to tissues from CT exposure. (orig.)

Radiation damages in solids and tissues

International Nuclear Information System (INIS)

Cevc, P.; Kogovsek, F.; Kanduser, A.; Peternelj, M.; Skaleric, U.; Funduk, N.

1977-01-01

In submitted research work we have studied radiation damages in ferroelectric crystals and application of ferroelectric crystals. Studying the radiation damages we have introduced new technique of EPR measurements under high hydrostatic pressure, that will enable us to obtain additional data on crystal lattice dynamics. A change of piroelectric coefficient with high radiation doses in dopped TGS has been measured also

Inherent risks associated with manufacture of bioengineered ocular surface tissue.

Science.gov (United States)

Schwab, Ivan R; Johnson, Nigel T; Harkin, Damien G

2006-12-01

To review the potential health risks associated with bioengineered ocular surface tissue, which serves as a bellwether for other tissues. All clinical trials using bioengineered ocular surface tissue published between July 1, 1996, and June 30, 2005, were reviewed with respect to materials used and statements of risk assessment, risk remediation, adverse events, manufacturing standards, and regulatory oversight. Ninety-five percent of investigational protocols used 1 or more animal-derived products and an overlapping 95% used 1 or more donor human tissues. Consideration of risks reveals a very low probability of potential harm but a significant risk of disability or death if such an event were to occur. Details of ethics approval, patient consent, and donor serologic test results were not consistently provided. No references were made to risk assessment or to codes of manufacturing and clinical practice. While a degree of risk is associated with bioengineered ocular surface tissue, investigational reports of this new technology have yet to address issues of risk management and regulatory oversight. Attention to risk and codes of manufacturing and clinical practice will be required for advancement of the technology. We suggest the adoption of international standards to address these issues.

Pretargeting CD45 enhances the selective delivery of radiation to hematolymphoid tissues in nonhuman primates

International Nuclear Information System (INIS)

Green, Damian J.; Pagel, John M.; Nemecek, Eneida R.; Lin, Yukang; Kenoyer, Aimee L.; Pantelias, Anastasia; Hamlin, Donald K.; Wilbur, D. S.; Fisher, Darrell R.; Rajendran, Joseph G.; Gopal, Ajay K.; Park, Steven I.; Press, Oliver W.

2009-01-01

Pretargeted radioimmunotherapy (PRIT) is designed to enhance the directed delivery of radionuclides to malignant cells. Through a series of studies in nineteen nonhuman primates (M. fascicularis) the potential therapeutic advantage of anti-CD45 PRIT was evaluated. Anti-CD45 PRIT demonstrated a significant improvement in target-to-normal organ ratios of absorbed radiation when compared to directly radiolabeled bivalent antibody (conventional radioimmunotherapy (RIT)). Radio-DOTA-biotin administered 48 hours after anti-CD45 streptavidin fusion protein (FP) (BC8 (scFv)4SA) produced markedly lower concentrations of radiation in non-target tissues when compared to conventional RIT. PRIT generated superior target:normal organ ratios in the blood, lung and liver (10.3:1, 18.9:1 and 9.9:1 respectively) when compared to the conventional RIT controls (2.6:1, 6.4:1 and 2.9:1 respectively). The FP demonstrated superior retention in target tissues relative to comparable directly radiolabeled bivalent anti-CD45 RIT. The time-point of administration of the second step radiolabeled ligand (radio-DOTA-biotin) significantly impacted the biodistribution of radioactivity in target tissues. Rapid clearance of the FP from the circulation rendered unnecessary the addition of a synthetic clearing agent in this model. These results support proceeding to anti-CD45 PRIT clinical trials for patients with both leukemia and lymphoma

Fibronectin distribution in epithelial and associated tissues of the rat

DEFF Research Database (Denmark)

Couchman, J R; Gibson, W T; Thom, D

1979-01-01

Specific antiserum was used to investigate the distribution of the extracellular glycoprotein, fibronectin, in rat skin and tongue tissue by light and electron microscopy with immunofluorescence and immunoperoxidase techniques. We conclude that fibronectin is absent from stable, differentiated...... parts of tissues, such as the sebaceous glands or the matrix, medulla, cortex, and cuticles of the hair and the inner and outer root sheaths, or even in tissues in which there is some cell movement, such as the epidermis. It is, however, characteristic of sites at which cell division is occurring...... in contact with an extracellular scaffolding, such as basement membrane or loose connective tissue. Conspicuous examples were in the glassy membrane and connective tissue sheath associated with the follicular epithelium, the basement membrane underlying vascular endothelial cells, the connective tissues...

Yeast communities from host plants and associated Drosophila in southern arizona: new isolations and analysis of the relative importance of hosts and vectors on comunity composition.

Science.gov (United States)

Ganter, Philip F; Starmer, William T; Lachance, Marc-Andre; Phaff, Herman J

1986-10-01

The yeast communities from slime fluxes of three deciduous trees (Prosopis juliflora, Populus fremontii and Quercus emoryi) and the necroses of two cacti (Opuntia phaeacantha and Carnegiea gigantea) were surveyed in the region of Tucson, Arizona. In addition, the yeasts carried by dipterans associated with the fluxes or necroses (Drosophila carbonaria, D. brooksae, D. nigrospiracula, D. mettleri, and Aulacigaster leucopeza) were sampled. The results indicate that each host sampled had a distinct community of yeasts associated with it. The dipterans, which can act as vectors of the yeasts, deposited yeasts from other sources in addition to those found on their associated hosts. It is argued that host plant physiology is relatively more important than the activity of the vector in determining yeast community composition. Furthermore, the average number of yeast species per flux or necrosis is not different from the average number of yeast species per fly. It is hypothesized that the vector may affect the number of species per individual flux or not, and that the number is lower than the rot or necrosis could potentially support.

Tissue bank. A new biomedical applications of ionizing radiation

International Nuclear Information System (INIS)

Rubio, Tatiana; Ribbeck, Jessica

1999-01-01

The entire staff of the Irradiation Section has helped to develop the semi-commercial application of two technological areas of irradiation: sterilization of medical supplies and food preservation. Some biomedical applications, such as the irradiation of whole blood and its components, as well as of different pharmaceutical and cosmetics products have also been routinely carried out. A Center for processing biological tissues has been added recently. At the end of 1996, a Tissue Bank for producing bone and skin grafts was evaluated and approved by the Chilean Nuclear Energy Commission (CCHEN). The first activities began the following year, and cooperation agreements with potential users were signed. At the same time the International Atomic Energy Agency (IAEA) sent an expert to give assistance, who also carried out a surgical operation with irradiated bone grafts in the Hospital del Trabajador. The year finished with the presentation to IAEA of a technical cooperation project, which was subsequently approved. A clean room where the Bank in formation will operate was set up in 1998 and the implementation of the laboratory was started with the support of the IAEA. At present the Bank has produced its first results with irradiated bone grafts, that have been used to close bronchopleural fistulas. By year's end more samples of bone grafts will be produced and sterilized by ionizing radiation, in compliance with the international standards. (author)

Evidence that breast tissue stiffness is associated with risk of breast cancer.

Science.gov (United States)

Boyd, Norman F; Li, Qing; Melnichouk, Olga; Huszti, Ella; Martin, Lisa J; Gunasekara, Anoma; Mawdsley, Gord; Yaffe, Martin J; Minkin, Salomon

2014-01-01

Evidence from animal models shows that tissue stiffness increases the invasion and progression of cancers, including mammary cancer. We here use measurements of the volume and the projected area of the compressed breast during mammography to derive estimates of breast tissue stiffness and examine the relationship of stiffness to risk of breast cancer. Mammograms were used to measure the volume and projected areas of total and radiologically dense breast tissue in the unaffected breasts of 362 women with newly diagnosed breast cancer (cases) and 656 women of the same age who did not have breast cancer (controls). Measures of breast tissue volume and the projected area of the compressed breast during mammography were used to calculate the deformation of the breast during compression and, with the recorded compression force, to estimate the stiffness of breast tissue. Stiffness was compared in cases and controls, and associations with breast cancer risk examined after adjustment for other risk factors. After adjustment for percent mammographic density by area measurements, and other risk factors, our estimate of breast tissue stiffness was significantly associated with breast cancer (odds ratio = 1.21, 95% confidence interval = 1.03, 1.43, p = 0.02) and improved breast cancer risk prediction in models with percent mammographic density, by both area and volume measurements. An estimate of breast tissue stiffness was associated with breast cancer risk and improved risk prediction based on mammographic measures and other risk factors. Stiffness may provide an additional mechanism by which breast tissue composition is associated with risk of breast cancer and merits examination using more direct methods of measurement.

Anticipated Intraoperative Electron Beam Boost, External Beam Radiation Therapy, and Limb-Sparing Surgical Resection for Patients with Pediatric Soft-Tissue Sarcomas of the Extremity: A Multicentric Pooled Analysis of Long-Term Outcomes

Energy Technology Data Exchange (ETDEWEB)

Sole, Claudio V., E-mail: cvsole@uc.cl [Department of Oncology, Hospital General Universitario Gregorio Marañón, Madrid (Spain); School of Medicine, Complutense University, Madrid (Spain); Service of Radiation Oncology, Instituto de Radiomedicina, Santiago (Chile); Calvo, Felipe A. [Department of Oncology, Hospital General Universitario Gregorio Marañón, Madrid (Spain); School of Medicine, Complutense University, Madrid (Spain); Polo, Alfredo [Service of Radiation Oncology, Hospital Universitario Ramón y Cajal, Madrid (Spain); Cambeiro, Mauricio [Service of Radiation Oncology, Clínica Universidad de Navarra, Pamplona (Spain); Alvarez, Ana; Gonzalez, Carmen [Service of Radiation Oncology, Hospital General Universitario Gregorio Marañón, Madrid (Spain); Gonzalez, Jose [Service of Pediatric Orthopedics and Traumatology, Hospital General Universitario Gregorio Marañón, Madrid (Spain); San Julian, Mikel [Service of Orthopedics and Traumatology, Clínica Universidad de Navarra, Pamplona (Spain); Martinez-Monge, Rafael [Service of Radiation Oncology, Clínica Universidad de Navarra, Pamplona (Spain)

2014-09-01

Purpose: To perform a joint analysis of data from 3 contributing centers within the intraoperative electron-beam radiation therapy (IOERT)-Spanish program, to determine the potential of IOERT as an anticipated boost before external beam radiation therapy in the multidisciplinary treatment of pediatric extremity soft-tissue sarcomas. Methods and Materials: From June 1993 to May 2013, 62 patients (aged <21 years) with a histologic diagnosis of primary extremity soft-tissue sarcoma with absence of distant metastases, undergoing limb-sparing grossly resected surgery, external beam radiation therapy (median dose 40 Gy) and IOERT (median dose 10 Gy) were considered eligible for this analysis. Results: After a median follow-up of 66 months (range, 4-235 months), 10-year local control, disease-free survival, and overall survival was 85%, 76%, and 81%, respectively. In multivariate analysis after adjustment for other covariates, tumor size >5 cm (P=.04) and R1 margin status (P=.04) remained significantly associated with local relapse. In regard to overall survival only margin status (P=.04) retained association on multivariate analysis. Ten patients (16%) reported severe chronic toxicity events (all grade 3). Conclusions: An anticipated IOERT boost allowed for external beam radiation therapy dose reduction, with high local control and acceptably low toxicity rates. The combined radiosurgical approach needs to be tested in a prospective trial to confirm these results.

Anticipated Intraoperative Electron Beam Boost, External Beam Radiation Therapy, and Limb-Sparing Surgical Resection for Patients with Pediatric Soft-Tissue Sarcomas of the Extremity: A Multicentric Pooled Analysis of Long-Term Outcomes

International Nuclear Information System (INIS)

Sole, Claudio V.; Calvo, Felipe A.; Polo, Alfredo; Cambeiro, Mauricio; Alvarez, Ana; Gonzalez, Carmen; Gonzalez, Jose; San Julian, Mikel; Martinez-Monge, Rafael

2014-01-01

Purpose: To perform a joint analysis of data from 3 contributing centers within the intraoperative electron-beam radiation therapy (IOERT)-Spanish program, to determine the potential of IOERT as an anticipated boost before external beam radiation therapy in the multidisciplinary treatment of pediatric extremity soft-tissue sarcomas. Methods and Materials: From June 1993 to May 2013, 62 patients (aged <21 years) with a histologic diagnosis of primary extremity soft-tissue sarcoma with absence of distant metastases, undergoing limb-sparing grossly resected surgery, external beam radiation therapy (median dose 40 Gy) and IOERT (median dose 10 Gy) were considered eligible for this analysis. Results: After a median follow-up of 66 months (range, 4-235 months), 10-year local control, disease-free survival, and overall survival was 85%, 76%, and 81%, respectively. In multivariate analysis after adjustment for other covariates, tumor size >5 cm (P=.04) and R1 margin status (P=.04) remained significantly associated with local relapse. In regard to overall survival only margin status (P=.04) retained association on multivariate analysis. Ten patients (16%) reported severe chronic toxicity events (all grade 3). Conclusions: An anticipated IOERT boost allowed for external beam radiation therapy dose reduction, with high local control and acceptably low toxicity rates. The combined radiosurgical approach needs to be tested in a prospective trial to confirm these results

Optimizing signal output: effects of viscoelasticity and difference frequency on vibroacoustic radiation of tissue-mimicking phantoms

Science.gov (United States)

Namiri, Nikan K.; Maccabi, Ashkan; Bajwa, Neha; Badran, Karam W.; Taylor, Zachary D.; St. John, Maie A.; Grundfest, Warren S.; Saddik, George N.

2018-02-01

Vibroacoustography (VA) is an imaging technology that utilizes the acoustic response of tissues to a localized, low frequency radiation force to generate a spatially resolved, high contrast image. Previous studies have demonstrated the utility of VA for tissue identification and margin delineation in cancer tissues. However, the relationship between specimen viscoelasticity and vibroacoustic emission remains to be fully quantified. This work utilizes the effects of variable acoustic wave profiles on unique tissue-mimicking phantoms (TMPs) to maximize VA signal power according to tissue mechanical properties, particularly elasticity. A micro-indentation method was utilized to provide measurements of the elastic modulus for each biological replica. An inverse relationship was found between elastic modulus (E) and VA signal amplitude among homogeneous TMPs. Additionally, the difference frequency (Δf ) required to reach maximum VA signal correlated with specimen elastic modulus. Peak signal diminished with increasing Δf among the polyvinyl alcohol specimen, suggesting an inefficient vibroacoustic response by the specimen beyond a threshold of resonant Δf. Comparison of these measurements may provide additional information to improve tissue modeling, system characterization, as well as insights into the unique tissue composition of tumors in head and neck cancer patients.

Ablation of biological tissues by radiation of strontium vapor laser

Energy Technology Data Exchange (ETDEWEB)

Soldatov, A. N., E-mail: general@tic.tsu.ru; Vasilieva, A. V., E-mail: anita-tomsk@mail.ru [National Research Tomsk State University, Lenin ave., 36, 634050, Tomsk (Russian Federation)

2015-11-17

A two-stage laser system consisting of a master oscillator and a power amplifier based on sources of self- contained transitions in pairs SrI and SrII has been developed. The radiation spectrum contains 8 laser lines generating in the range of 1 – 6.45 μm, with a generation pulse length of 50 – 150 ns, and pulse energy of ∼ 2.5 mJ. The divergence of the output beam was close to the diffraction and did not exceed 0.5 mrad. The control range of the laser pulse repetition rate varied from 10 to 15 000 Hz. The given laser system has allowed to perform ablation of bone tissue samples without visible thermal damage.

Association Between Treatment at High-Volume Facilities and Improved Overall Survival in Soft Tissue Sarcomas.

Science.gov (United States)

Venigalla, Sriram; Nead, Kevin T; Sebro, Ronnie; Guttmann, David M; Sharma, Sonam; Simone, Charles B; Levin, William P; Wilson, Robert J; Weber, Kristy L; Shabason, Jacob E

2018-03-15

Soft tissue sarcomas (STS) are rare malignancies that require complex multidisciplinary management. Therefore, facilities with high sarcoma case volume may demonstrate superior outcomes. We hypothesized that STS treatment at high-volume (HV) facilities would be associated with improved overall survival (OS). Patients aged ≥18 years with nonmetastatic STS treated with surgery and radiation therapy at a single facility from 2004 through 2013 were identified from the National Cancer Database. Facilities were dichotomized into HV and low-volume (LV) cohorts based on total case volume over the study period. OS was assessed using multivariable Cox regression with propensity score-matching. Patterns of care were assessed using multivariable logistic regression analysis. Of 9025 total patients, 1578 (17%) and 7447 (83%) were treated at HV and LV facilities, respectively. On multivariable analysis, high educational attainment, larger tumor size, higher grade, and negative surgical margins were statistically significantly associated with treatment at HV facilities; conversely, black race and non-metropolitan residence were negative predictors of treatment at HV facilities. On propensity score-matched multivariable analysis, treatment at HV facilities versus LV facilities was associated with improved OS (hazard ratio, 0.87, 95% confidence interval, 0.80-0.95; P = .001). Older age, lack of insurance, greater comorbidity, larger tumor size, higher tumor grade, and positive surgical margins were associated with statistically significantly worse OS. In this observational cohort study using the National Cancer Database, receipt of surgery and radiation therapy at HV facilities was associated with improved OS in patients with STS. Potential sociodemographic disparities limit access to care at HV facilities for certain populations. Our findings highlight the importance of receipt of care at HV facilities for patients with STS and warrant further study into improving access to

Criteria for personal dosimetry in mixed radiation fields in space. [analyzing trapped protons, tissue disintegration stars, and neutrons

Science.gov (United States)

Schaefer, H. J.

1974-01-01

The complexity of direct reading and passive dosimeters for monitoring radiation is studied to strike the right balance of compromise to simplify the monitoring procedure. Trapped protons, tissue disintegration stars, and neutrons are analyzed.

Study of non-thermal effects from laser radiation on live tissues

International Nuclear Information System (INIS)

Cotta, M.A.

1987-02-01

The functional biological effects related to the irradiation of live tissues with low power lasers, called non-thermal effects were theoretical and experimentally studied. For the experimental part, a device which allows to: irradiation lesions artificially created on the back of rats by a He-Ne laser, or put a moving ground glass in front of the laser beam, by irradiation of this same laser with its coherence degree decreased. The relevance of the radiation coherence in the lesion cicatrization process was shown. The electrical field distribution and the intensity distribution on a surface with micro-roughness when irradiated by coherent light are theoretically studied. (M.C.K.) [pt

Modification by cystamine of radiation-induced free radical damages to biomolecules in tissues of mouse organs

International Nuclear Information System (INIS)

Svistunenko, D.A.; Gudtsova, K.V.

1989-01-01

The method of low-temperature ESR-spectroscopy was used to study a modifying effect of cystamine on the yield of radiation-induced free radicals in different biomolecules of liver and spleen tissues of mice. Intraperitoneal administration of cystamine (150 mg/kg) 15 min before isolation and freezing of the tissues was shown to reduce by 11 per cent the yield of radicals of H-adducts of thymine DNA bases, to decrease by 23 per cent the yield of radicals of triacyglycerol and phospholipid radiolysis, and to increase by 24 per cent the yield of radicals of lipid fatty acid residues in splenic tissues. According to the criterion used, cystamine has no modyfying action on the yield of free-radical damages to liver biomolecules

Effect of radiation and other cytotoxic agents on the growth of cells cultured from normal and tumor tissues from the female genital tract

International Nuclear Information System (INIS)

Mothersill, C.; Seymour, C.B.; Bonnar, J.

1990-01-01

A technique is presented which allows the response of human gynecological tissue to radiation and cytotoxic drugs to be assessed using a tissue culture explant system. The technique is simple to use and gives results in line with those obtained for human tissues by more complex culture methods. Data are presented showing how the explant technique developed by the group for other tissues can be adapted to yield acceptable results for normal tissue response to radiation. The potential of the technique for use in predictive testing of individual tumor response is then assessed in five cases of gynecological malignancy. It is clear that variations in sensitivity to different radio- and chemotherapy agents and combinations can be detected. The results obtained require clinical validation and it is hoped that this will come over the next few years from evaluation of patient response to treatment using individually optimized, rather than empirical therapy

Association of intraoperative tissue oxygenation with suspected risk factors for tissue hypoxia.

Science.gov (United States)

Spruit, R J; Schwarte, L A; Hakenberg, O W; Scheeren, T W L

2013-10-01

Tissue hypoxia may cause organ dysfunction, but not much is known about tissue oxygenation in the intraoperative setting. We studied microcirculatory tissue oxygen saturation (StO₂) to determine representative values for anesthetized patients undergoing urological surgery and to test the hypothesis that StO₂ is associated with known perioperative risk factors for morbidity and mortality, conventionally monitored variables, and hypotension requiring norepinephrine. Using near-infrared spectroscopy, we measured StO₂ on the thenar eminence in 160 patients undergoing open urological surgery under general anesthesia (FiO2 0.35-0.4), and calculated its correlations with age, risk level for general perioperative complications and mortality (high if age ≥70 and procedure is radical cystectomy), mean arterial pressure (MAP), hemoglobin concentration (Hb), central venous oxygen saturation (ScvO₂), and norepinephrine use. The time averaged StO₂ was 86 ± 6 % (mean ± SD). In the multivariate analysis, Hb [standardized coefficient (SC) 0.21, p = 0.003], ScvO₂ (SC 0.53, p SStO₂ was partly dependent on MAP only when this was below 65 mmHg (lowest MAP SC 0.20, p = 0.006, MAP area under the curve <65 mmHg SC 0.03, p = 0.02). Finally, StO₂ was slightly lower in patients requiring norepinephrine (85 ± 6 vs. 89 ± 6 %, p = 0.001). Intraoperative StO₂ in urological patients was comparable to that of healthy volunteers breathing room air as reported in the literature and correlated with known perioperative risk factors. Further research should investigate its association with outcome and the effect of interventions aimed at optimizing StO₂.

Optical imaging of oral pathological tissue using optical coherence tomography and synchrotron radiation computed microtomography

Science.gov (United States)

Cânjǎu, Silvana; Todea, Carmen; Sinescu, Cosmin; Negrutiu, Meda L.; Duma, Virgil; Mǎnescu, Adrian; Topalǎ, Florin I.; Podoleanu, Adrian Gh.

2013-06-01

The efforts aimed at early diagnosis of oral cancer should be prioritized towards developing a new screening instrument, based on optical coherence tomography (OCT), to be used directly intraorally, able to perform a fast, real time, 3D and non-invasive diagnosis of oral malignancies. The first step in this direction would be to optimize the OCT image interpretation of oral tissues. Therefore we propose plastination as a tissue preparation method that better preserves three-dimensional structure for study by new optical imaging techniques. The OCT and the synchrotron radiation computed microtomography (micro-CT) were employed for tissue sample analyze. For validating the OCT results we used the gold standard diagnostic procedure for any suspicious lesion - histopathology. This is a preliminary study of comparing features provided by OCT and Micro-CT. In the conditions of the present study, OCT proves to be a highly promising imaging modality. The use of x-ray based topographic imaging of small biological samples has been limited by the low intrinsic x-ray absorption of non-mineralized tissue and the lack of established contrast agents. Plastination can be used to enhance optical imagies of oral soft tissue samples.

Vasculitis associated with connective tissue diseases.

Science.gov (United States)

Cozzani, E; Gasparini, G; Papini, M; Burlando, M; Drago, F; Parodi, A

2015-04-01

Vasculitis in connective tissue disease (CTD) is quite rare, it is reported in approximately 10% of patients with CTD; systemic lupus erythematosus (SLE) shows the highest association rate. Vessels of any size may be involved, but mainly small vessels vasculitis is reported. At present the classification of these vasculitis is unsatisfactory. According to the 2012 revised International Chapel Hill Consensus Conference, vasculitides secondary to CTD are a well identified entity and are classified under the category of "vasculitis associated with systemic disease". However only lupus vasculitis and rheumatoid vasculitis are explicitly listed, while the remaining are generically included under the heading "others". Petechiae, purpura, gangrene and ulcers are the most frequent cutaneous manifestations that should investigated in order to rule out potentially dangerous systemic involvement, especially if cryoglobulinemic or necrotizing vasculitis are suspected. This review will focus on the cutaneous involvement in CTD associated vasculitis.

[Radiation-induced bystander effect: the important part of ionizing radiation response. Potential clinical implications].

Science.gov (United States)

Wideł, Maria; Przybyszewski, Waldemar; Rzeszowska-Wolny, Joanna

2009-08-18

It has long been a central radiobiological dogma that the damaging effects of ionizing radiation, such as cell death, cytogenetic changes, apoptosis, mutagenesis, and carcinogenesis, are the results of the direct ionization of cell structures, particularly DNA, or indirect damage via water radiolysis products. However, several years ago attention turned to a third mechanism of radiation, termed the "bystander effect" or "radiation-induced bystander effect" (RIBE). This is induced by agents and signals emitted by directly irradiated cells and manifests as a lowering of survival, cytogenetic damage, apoptosis enhancement, and biochemical changes in neighboring non-irradiated cells. The bystander effect is mainly observed in in vitro experiments using very low doses of alpha particles (range; mGy, cGy), but also after conventional irradiation (X-rays, gamma rays) at low as well as conventional doses. The mechanisms responsible for the bystander effect are complex and still poorly understood. It is believed that molecular signals released from irradiated cells induce different signaling ways in non-irradiated neighboring cells, leading to the observed events. The molecular signals may be transmitted through gap junction intercellular communication and through a medium transfer mechanism. The nature of these transmitted factors are diverse, and still not definitely established. It seems that RIBE may have important clinical implications for health risk associated with radiation exposure. Potentially, this effect may have important implications in the creation of whole-body or localized side effects in tissues beyond the irradiation field and also in low-dose radiological and radioisotope diagnostics. Factors emitted by irradiated cells may result in the risk of genetic instability, mutations, and second primary cancer induction. They might also have their own part in inducing and extending post-radiation side effects in normal tissue. The bystander effect may be a

Radiation-induced bystander effect: The important part of ionizing radiation response. Potential clinical implications

Directory of Open Access Journals (Sweden)

Maria Wideł

2009-08-01

Full Text Available It has long been a central radiobiological dogma that the damaging effects of ionizing radiation, such as cell death, cytogenetic changes, apoptosis, mutagenesis, and carcinogenesis, are the results of the direct ionization of cell structures, particularly DNA, or indirect damage via water radiolysis products. However, several years ago attention turned to a third mechanism of radiation, termed the “bystander effect” or “radiation-induced bystander effect” (RIBE. This is induced by agents and signals emitted by directly irradiated cells and manifests as a lowering of survival, cytogenetic damage, apoptosis enhancement, and biochemical changes in neighboring non-irradiated cells. The bystander effect is mainly observed in in vitro experiments using very low doses of alpha particles (range; mGy, cGy, but also after conventional irradiation (X-rays, gamma rays at low as well as conventional doses. The mechanisms responsible for the bystander effect are complex and still poorly understood. It is believed that molecular signals released from irradiated cells induce different signaling ways in non-irradiated neighboring cells, leading to the observed events. The molecular signals may be transmitted through gap junction intercellular communication and through a medium transfer mechanism. The nature of these transmitted factors are diverse, and still not defi nitely established. It seems that RIBE may have important clinical implications for health risk associated with radiation exposure. Potentially, this effectmay have important implications in the creation of whole-body or localized side effects in tissues beyond the irradiation fi eld and also in low-dose radiological and radioisotope diagnostics. Factors emitted by irradiated cells may result in the risk of genetic instability, mutations, and second primary cancer induction. They might also have their own part in inducing and extending post-radiation side effects in normal tissue. The

Simultaneous inference of phenotype-associated genes and relevant tissues from GWAS data via Bayesian integration of multiple tissue-specific gene networks.

Science.gov (United States)

Wu, Mengmeng; Lin, Zhixiang; Ma, Shining; Chen, Ting; Jiang, Rui; Wong, Wing Hung

2017-12-01

Although genome-wide association studies (GWAS) have successfully identified thousands of genomic loci associated with hundreds of complex traits in the past decade, the debate about such problems as missing heritability and weak interpretability has been appealing for effective computational methods to facilitate the advanced analysis of the vast volume of existing and anticipated genetic data. Towards this goal, gene-level integrative GWAS analysis with the assumption that genes associated with a phenotype tend to be enriched in biological gene sets or gene networks has recently attracted much attention, due to such advantages as straightforward interpretation, less multiple testing burdens, and robustness across studies. However, existing methods in this category usually exploit non-tissue-specific gene networks and thus lack the ability to utilize informative tissue-specific characteristics. To overcome this limitation, we proposed a Bayesian approach called SIGNET (Simultaneously Inference of GeNEs and Tissues) to integrate GWAS data and multiple tissue-specific gene networks for the simultaneous inference of phenotype-associated genes and relevant tissues. Through extensive simulation studies, we showed the effectiveness of our method in finding both associated genes and relevant tissues for a phenotype. In applications to real GWAS data of 14 complex phenotypes, we demonstrated the power of our method in both deciphering genetic basis and discovering biological insights of a phenotype. With this understanding, we expect to see SIGNET as a valuable tool for integrative GWAS analysis, thereby boosting the prevention, diagnosis, and treatment of human inherited diseases and eventually facilitating precision medicine.

Ischemia and reperfusion in skin flaps: effects of mannitol and vitamin C in reducing necrosis area in a rat experimental model Isquemia e reperfusão de retalhos cutâneos: efeitos do manitol e vitamina C na redução de áreas de necrose em modelo experimental no rato

Directory of Open Access Journals (Sweden)

Winston Bonetti Yoshida

2005-10-01

Full Text Available PURPOSE: The aim of the present study was to develop an experimental model of ischemia-reperfusion injury in rat skin flap and to verify the effect of mannitol and vitamin C on reducing necrosis area. METHODS: A 6-x 3-cm groin skin flap was raised and submitted to 8 hours of ischemia by clamping the vascular pedicle and to 7 days of reperfusion. The animals were divided in four groups: S1 and S2 (10 animals each and C and T (14 animals each. In groups S1 and S2 skin flaps were not submitted to ischemia and animals received lactated Ringer's solution (S1 and antioxidant solution (S2 . In groups C and T, flaps were subjected to 8 hours of warm ischemia and animals received Lactated Ringer's solution (Group C and antioxidant solution immediately before reperfusion, (Group T. Flap survival was evaluated on the seventh day using a paper template technique and computer-assistant imaging analysis of necrotic and normal areas. RESULTS: Statistical analysis showed no area differences between groups C and T. CONCLUSION: The experimental model provided consistent necrotic area in control groups and drugs used were not effective in improving skin flap survival.OBJETIVO: Neste trabalho foi padronizado modelo experimental de isquemia e reperfusão em retalho cutâneo em ratos no qual estudou-se possibilidade de uma solução antioxidante, composta por Ringer lactato, vitamina C e manitol de reduzir a área de necrose. MÉTODOS: O modelo consistiu de levantamento de retalho cutâneo axial de 6,0 x 3,0cm, submetido à isquemia de 8 horas e reperfusão de 7 dias. Os animais foram divididos em quatro grupos: grupos S1, S2 (10 animais cada, C e T (14 animais cada. Nos grupos S1 e S2 todos os procedimentos dos demais grupos foram efetuados, exceto a isquemia e reperfusão: S1 recebeu apenas Ringer lactato e S2 a solução antioxidante. Os grupos C e T foram submetidos à isquemia. O grupo C recebeu somente Ringer lactato e o grupo T a solução antioxidante. No 7

Review of Research Projects on Qualitative and Quantitative Effects of Radiation on Haematopoietic Tissue in Man and Experimental Animal

Energy Technology Data Exchange (ETDEWEB)

Hilberg, A. W. [Division of Radiological Health, Department of Health, Education and Welfare, Rockville, MD (United States)

1967-07-15

By way of introduction to a review of Research Projects of the Division of Radiological Health concerned with effects of radiation on the haematopoietic tissue in man and the experimental animal, I should like first to discuss briefly the organization of research. Our research is organized into three major disciplines: (1) Epidemiology, (2) Radiation biology, and (3) Environmental sciences. Briefly, epidemiology is concerned with studies, of populations and effects of radiation in.man; radiation biology is concerned with effects in the experimental animal under controlled situations and also concerned with basic research in cellular and sub-cellular effects; and environmental science is concerned with transport mechanisms in the biosphere and how these mechanisms may operate and be interrupted to reduce radiation hazard to man.

Untargeted effects of ionizing radiation: Implications for radiation pathology

International Nuclear Information System (INIS)

Wright, Eric G; Coates, Philip J

2006-01-01

The dogma that genetic alterations are restricted to directly irradiated cells has been challenged by observations in which effects of ionizing radiation, characteristically associated with the consequences of energy deposition in the cell nucleus, arise in non-irradiated cells. These, so called, untargeted effects are demonstrated in cells that have received damaging signals produced by irradiated cells (radiation-induced bystander effects) or that are the descendants of irradiated cells (radiation-induced genomic instability). Radiation-induced genomic instability is characterized by a number of delayed adverse responses including chromosomal abnormalities, gene mutations and cell death. Similar effects, as well as responses that may be regarded as protective, have been attributed to bystander mechanisms. Whilst the majority of studies to date have used in vitro systems, some adverse non-targeted effects have been demonstrated in vivo. However, at least for haemopoietic tissues, radiation-induced genomic instability in vivo may not necessarily be a reflection of genomically unstable cells. Rather the damage may reflect responses to ongoing production of damaging signals; i.e. bystander responses, but not in the sense used to describe the rapidly induced effects resulting from direct interaction of irradiated and non-irradiated cells. The findings are consistent with a delayed and long-lived tissue reaction to radiation injury characteristic of an inflammatory response with the potential for persisting bystander-mediated damage. An important implication of the findings is that contrary to conventional radiobiological dogma and interpretation of epidemiologically-based risk estimates, ionizing radiation may contribute to malignancy and particularly childhood leukaemia by promoting initiated cells rather than being the initiating agent. Untargeted mechanisms may also contribute to other pathological consequences

Comparison of incidences of normal tissue complications with tumor response in a phase III trial comparing heat plus radiation to radiation alone

International Nuclear Information System (INIS)

Dewhirst, M.W.; Sim, D.A.; Grochowski, K.J.

1984-01-01

The success of hyperthermia (/sup Δ/) as an adjuvant to radiation (XRT) will depend on whether the increase in tumor control is greater than that for normal tissue reactions. One hundred and thirty dogs and cats were stratified by histology and randomized to receive XRT (460 rads per fraction, two fractions per week, for eight fractions) or /sup Δ/ + XRT (30 min. at 44 +-2 0 C; one fraction per week, four fractions; immediately prior to XRT). Heat induced changes in tumor and normal tissue responses were made by comparing ratios of incidence for /sup Δ/ + XRT and XRT alone (TRR; Thermal Relative Risk). Change in tumor response duration was calculated from statistical analysis of response duration curves (RRR; Relative Relapse Rate). Heat increased early normal tissue reactions (moist desquamation and mucositis by a factor of 1.08. Tumor complete response, by comparison, was significantly improved (TRR = 2.12, p < .001). Late skin fibrosis was also increased (TRR = 1.51), but the prolongation in tumor response was greater (RRR 1.85). The degree of thermal enhancement for all tissues was dependent on the minimum temperature achieved on the first treatment, but the values for tumor were consistently greater than those achieved for normal tissues

Normal tissue tolerance to external beam radiation therapy: Skin

International Nuclear Information System (INIS)

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

2010-01-01

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

Vascular lesions following radiation

International Nuclear Information System (INIS)

Fajardo, L.F.; Berthrong, M.

1988-01-01

The special radiation sensitivity of the vascular system is mainly linked to that of endothelial cells, which are perhaps the most radiation-vulnerable elements of mesenchymal tissues. Within the vascular tree, radiation injures most often capillaries, sinusoids, and small arteries, in that order. Lesions of veins are observed less often, but in certain tissues the veins are regularly damaged (e.g., intestine) or are the most affected structures (i.e., liver). Large arteries do suffer the least; however, when significant damage does occur in an elastic artery (e.g., thrombosis or rupture), it tends to be clinically significant and even fatal. Although not always demonstrable in human tissues, radiation vasculopathy generally is dose and time dependent. Like other radiation-induced lesions, the morphology in the vessels is not specific, but it is characteristic enough to be often recognizable. Vascular injury, especially by therapeutic radiation is not just a morphologic marker. It is a mediator of tissue damage; perhaps the most consistent pathogenetic mechanism in delayed radiation injury

Radiation Therapy for Control of Soft-Tissue Sarcomas Resected With Positive Margins

International Nuclear Information System (INIS)

DeLaney, Thomas F.; Kepka, Lucyna; Goldberg, Saveli I.; Hornicek, Francis J.; Gebhardt, Mark C.; Yoon, Sam S.; Springfield, Dempsey S.; Raskin, Kevin A.; Harmon, David C.; Kirsch, David G.; Mankin, Henry J.; Rosenberg, Andrew E.; Nielsen, G. Petur; Suit, Herman D.

2007-01-01

Purpose: Positive margins (PM) remain after surgery in some soft-tissue sarcoma (STS) patients. We investigated the efficacy of radiation therapy (RT) in STS patients with PM. Methods and Materials: A retrospective chart review was performed on 154 patients with STS at various anatomic sites with PM, defined as tumor on ink, who underwent RT with curative intent between 1970 and 2001. Local control (LC), disease-free survival (DFS), and overall survival (OS) rates were evaluated by univariate (log-rank) and multivariate analysis of prognostic and treatment factors. Results: At 5 years, actuarial LC, DFS, and OS rates were: 76%, 46.7%, and 65.2%, respectively. LC was highest with extremity lesions (p 64 Gy (p 64 Gy had higher 5-year LC, DFS, and OS rates of 85%, 52.1%, and 67.8% vs. 66.1%, 41.8%, and 62.9% if ≤64 Gy, p 50), also significantly influenced OS. By multivariate analysis, the best predictors of LC were site (extremity vs. other), p 64 vs. ≤64 Gy), p 64 Gy, superficial location, and extremity site are associated with improved LC. OS is worse in patients with tumors with lesions >5 cm, grossly positive margins, and after local failure

The regeneration of epidermal cells of Saintpaulia leaves as a new plant-tissue system for cellular radiation biology

International Nuclear Information System (INIS)

Engels, F.M.; Laan, F.M. van der; Leenhouts, H.P.; Chadwick, K.H.

1980-01-01

investigation of the nucleus of epidermal cells of the petioles of Saintpaulia leaves by cytofluorimetry revealed that all cells are in a non-cycling pre DNA synthesis phase. Cultivation of dissected leaves results in a synchronous regeneration process of a defined number of cells. Five days after onset of cultivation the cells reach the first mitosis. The nuclear development during the regeneration process is described. Irradiation of the leaves results in a directly visible inhibition of this regenerating capability which is used to quantify cell survival in a tissue. The data show that the radiation response has a similar shape to that of the survival of single cells in culture. This response can be observed before the first mitosis of the cells and its application as a new plant tissue system for cellular radiation research is discussed. (author)

The release of bystander factor(s) from tissue explant cultures of rainbow trout (Onchorhynchus mykiss) after exposure to gamma radiation.

Science.gov (United States)

O'Dowd, Colm; Mothersill, Carmel E; Cairns, Michael T; Austin, Brian; McClean, Brendan; Lyng, Fiona M; Murphy, James E J

2006-10-01

The bystander response has been documented in cell lines and cell cultures derived from aquatic species over the past several years. However, little work has been undertaken to identify a similar bystander response in tissue explant cultures from fish. In this study, indirect effects of ionizing gamma radiation on tissue explant cultures of fish were investigated. Tissue explants in culture were exposed to 0.5 Gy and 5 Gy gamma radiation from a 60Co teletherapy unit. A bystander response in Epithelioma papulosum cyprini (EPC) cells exposed to gamma-irradiated tissue conditioned medium from rainbow trout explants was investigated, and the effects on cell survival were quantified by the clonogenic survival assay. Dichlorofluorescein and rhodamine 123 fluorescent dyes were used to identify alterations in reactive oxygen species (ROS) and mitochondrial membrane potential (MMP), respectively. Results indicate a different response for the three tissue types investigated. Clonogenic assay results vary from a decrease in cell survival (gill) to no effect (skin) to a stimulatory effect (spleen). Results from fluorescence assays of ROS and MMP show similarities to clonogenic assay results. This study identifies a useful model for further studies relating to the bystander effect in aquatic organisms in vivo and ex vivo.

Solar radiation is inversely associated with inflammatory bowel disease admissions.

Science.gov (United States)

Jaime, Francisca; Riutort, Maria C; Alvarez-Lobos, Manuel; Hoyos-Bachiloglu, Rodrigo; Camargo, Carlos A; Borzutzky, Arturo

To explore the associations between latitude and solar radiation with inflammatory bowel disease admission rates in Chile, the country with the largest variation in solar radiation in the world. This is an ecological study, which included data on all hospital-admitted population for inflammatory bowel disease between 2001 and 2012, according to different latitudes and solar radiation exposures in Chile. The data were acquired from the national hospital discharge database from the Department of Health Statistics and Information of the Chilean Ministry of Health. Between 2001 and 2012 there were 12,869 admissions due to inflammatory bowel disease (69% ulcerative colitis, 31% Crohn's disease). Median age was 36 years (IQR: 25-51); 57% were female. The national inflammatory bowel disease admission rate was 6.52 (95% CI: 6.40-6.63) per 100,000 inhabitants with increasing rates over the 12-year period. In terms of latitude, the highest admission rates for pediatric ulcerative colitis and Crohn's disease, as well as adult ulcerative colitis, were observed in the southernmost region with lowest annual solar radiation. Linear regression analysis showed that regional solar radiation was inversely associated with inflammatory bowel disease admissions in Chile (β: -.44, p = .03). Regional solar radiation was inversely associated with inflammatory bowel disease admission rates in Chile; inflammatory bowel disease admissions were highest in the southernmost region with lowest solar radiation. Our results support the potential role of vitamin D deficiency on inflammatory bowel disease flares.

Development and Characterization of Tissue Equivalent Proportional Counter for Radiation Monitoring in International Space Station

Directory of Open Access Journals (Sweden)

Uk-Won Nam

2013-06-01

Full Text Available Tissue equivalent proportional counter (TEPC can measure the Linear Energy Transfer (LET spectrum and calculate the equivalent dose for the complicated radiation field in space. In this paper, we developed and characterized a TEPC for radiation monitoring in International Space Station (ISS. The prototype TEPC which can simulate a 2 μm of the site diameter for micro-dosimetry has been tested with a standard alpha source (241Am, 5.5 MeV. Also, the calibration of the TEPC was performed by the 252Cf neutron standard source in Korea Research Institute of Standards and Science (KRISS. The determined calibration factor was kf = 3.59×10-7 mSv/R.

Studies on implantation of 198Au-grain as a radiation therapy to cancer tissue

International Nuclear Information System (INIS)

Machida, Seiro

1975-01-01

The most effective dose of 198 Au-grain to be implanted and the clinicopathological findings after treatment are discussed. A safe dose of 198 Au-grain which could be implanted subcutaneously in rats, was under 2 mCi migration of 198 Au-grain was not recognized. In Yoshida sarcoma, transplanted subcutaneously into the backs of rats the most effective dose of 198 Au-grain was 2mCi/g of tumour tissue. However, about half of the rats implanted with this dosage died from the growing tumour. Histological examination of the implanted tumour tissue, revealed necrosis within a distance of only 0.4 mm from 198 Au-grain particles. In small metastatic tumours after 198 Au-grain implantation, there was necrosis i.e. pyknosis and karyolysis of the tumour cells, fibrosis and hyaline degeneration of the stroma. However, hardly any change in tumour size was detectable because of swelling and induration around the tumour. In some of the cases treated with 198 Au-grain combined with 60 Co or with chemotherapeutics, the tumour size was evidently reduced and became non-palable. Side effects were minimal except in one case which was afflicted temporarily with radiation sickness after an implantation of 200 mCi 198 Au-grain. In conclusion, the implantation of 198 Au-grain into the tumour was found to be very safe for the patients with surgically incurable cancer. Because of the short range of 198 Au-grain radioactivity, homogeneous density of 198 Au-grain into the whole tumour tissue is required. A combination with other radiations and/or with chemotherapeutics is also recommended. (author)

Proceedings of 8th Symposium of the Croatian Radiation Protection Association

Energy Technology Data Exchange (ETDEWEB)

Krajcar Bronic, I; Kopjar, N; Milic, M; Branica, G

2011-07-01

The 8th symposium of the Croatian Radiation Protection Association discussed the following topics: general topics; radiation dosimetry and instrumentation; public exposure; biological effects of radiation; radiation protection in medicine; radioecology and non-ionizing radiation. For each subject many investigations, experiments, examples and results are presented. International character of this symposium shows importance of these topics not only in region but world wide.

Proceedings of 8th Symposium of the Croatian Radiation Protection Association

International Nuclear Information System (INIS)

Krajcar Bronic, I.; Kopjar, N.; Milic, M.; Branica, G.

2011-01-01

The 8th symposium of the Croatian Radiation Protection Association discussed the following topics: general topics; radiation dosimetry and instrumentation; public exposure; biological effects of radiation; radiation protection in medicine; radioecology and non-ionizing radiation. For each subject many investigations, experiments, examples and results are presented. International character of this symposium shows importance of these topics not only in region but world wide.

Proceedings of the Conference and Symposium Korean Association for Radiation Protection Fall Meeting 2016

Energy Technology Data Exchange (ETDEWEB)

NONE

2016-12-15

This proceedings contains articles of the Korean Association for Radiation Protection Fall Meeting, 2016. It was held on Dec. 1, 2016 Phoenix Island in Jeju, Korea and subject of the Korean Association for Radiation Protection Fall Meeting 2016. This proceedings is comprised of 5 sessions. The main topic titles of session are as follows: Radiation protection, Biotechnology of radiation, Radiation measurement, Radiation environment and prevention, Radiation epidemiography.

Systematic analysis of gene expression patterns associated with postmortem interval in human tissues.

Science.gov (United States)

Zhu, Yizhang; Wang, Likun; Yin, Yuxin; Yang, Ence

2017-07-14

Postmortem mRNA degradation is considered to be the major concern in gene expression research utilizing human postmortem tissues. A key factor in this process is the postmortem interval (PMI), which is defined as the interval between death and sample collection. However, global patterns of postmortem mRNA degradation at individual gene levels across diverse human tissues remain largely unknown. In this study, we performed a systematic analysis of alteration of gene expression associated with PMI in human tissues. From the Genotype-Tissue Expression (GTEx) database, we evaluated gene expression levels of 2,016 high-quality postmortem samples from 316 donors of European descent, with PMI ranging from 1 to 27 hours. We found that PMI-related mRNA degradation is tissue-specific, gene-specific, and even genotype-dependent, thus drawing a more comprehensive picture of PMI-associated gene expression across diverse human tissues. Additionally, we also identified 266 differentially variable (DV) genes, such as DEFB4B and IFNG, whose expression is significantly dispersed between short PMI (S-PMI) and long PMI (L-PMI) groups. In summary, our analyses provide a comprehensive profile of PMI-associated gene expression, which will help interpret gene expression patterns in the evaluation of postmortem tissues.

Parallel beam microradiography of dental hard tissue using synchrotron radiation and X-ray image magnification

International Nuclear Information System (INIS)

Takagi, S.; Chow, L.C.; Brown, W.E.; Dobbyn, R.C.; Kuriyama, M.

1984-01-01

A novel technique utilizing a highly parallel beam of monochromatic synchrotron radiation combined with X-ray image magnification has been used to obtain microradiographs of caries lesions in relatively thick tooth sections. Preliminary results reveal structural features not previously reported. This technique holds the promise of allowing one to follow the structural changes accompanying the formation, destruction and chemical repair of mineralized tissue in real time. (orig.)

A System for Continual Quality Improvement of Normal Tissue Delineation for Radiation Therapy Treatment Planning

Energy Technology Data Exchange (ETDEWEB)

Breunig, Jennifer; Hernandez, Sophy; Lin, Jeffrey; Alsager, Stacy; Dumstorf, Christine; Price, Jennifer; Steber, Jennifer; Garza, Richard; Nagda, Suneel; Melian, Edward; Emami, Bahman [Department of Radiation Oncology, Loyola University Medical Center, Maywood, Illinois (United States); Roeske, John C., E-mail: jroeske@lumc.edu [Department of Radiation Oncology, Loyola University Medical Center, Maywood, Illinois (United States)

2012-08-01

Purpose: To implement the 'plan-do-check-act' (PDCA) cycle for the continual quality improvement of normal tissue contours used for radiation therapy treatment planning. Methods and Materials: The CT scans of patients treated for tumors of the brain, head and neck, thorax, pancreas and prostate were selected for this study. For each scan, a radiation oncologist and a diagnostic radiologist, outlined the normal tissues ('gold' contours) using Radiation Therapy Oncology Group (RTOG) guidelines. A total of 30 organs were delineated. Independently, 5 board-certified dosimetrists and 1 trainee then outlined the same organs. Metrics used to compare the agreement between the dosimetrists' contours and the gold contours included the Dice Similarity Coefficient (DSC), and a penalty function using distance to agreement. Based on these scores, dosimetrists were re-trained on those organs in which they did not receive a passing score, and they were subsequently re-tested. Results: Passing scores were achieved on 19 of 30 organs evaluated. These scores were correlated to organ volume. For organ volumes <8 cc, the average DSC was 0.61 vs organ volumes {>=}8 cc, for which the average DSC was 0.91 (P=.005). Normal tissues that had the lowest scores included the lenses, optic nerves, chiasm, cochlea, and esophagus. Of the 11 organs that were considered for re-testing, 10 showed improvement in the average score, and statistically significant improvement was noted in more than half of these organs after education and re-assessment. Conclusions: The results of this study indicate the feasibility of applying the PDCA cycle to assess competence in the delineation of individual organs, and to identify areas for improvement. With testing, guidance, and re-evaluation, contouring consistency can be obtained across multiple dosimetrists. Our expectation is that continual quality improvement using the PDCA approach will ensure more accurate treatments and dose

A System for Continual Quality Improvement of Normal Tissue Delineation for Radiation Therapy Treatment Planning

International Nuclear Information System (INIS)

Breunig, Jennifer; Hernandez, Sophy; Lin, Jeffrey; Alsager, Stacy; Dumstorf, Christine; Price, Jennifer; Steber, Jennifer; Garza, Richard; Nagda, Suneel; Melian, Edward; Emami, Bahman; Roeske, John C.

2012-01-01

Purpose: To implement the “plan-do-check-act” (PDCA) cycle for the continual quality improvement of normal tissue contours used for radiation therapy treatment planning. Methods and Materials: The CT scans of patients treated for tumors of the brain, head and neck, thorax, pancreas and prostate were selected for this study. For each scan, a radiation oncologist and a diagnostic radiologist, outlined the normal tissues (“gold” contours) using Radiation Therapy Oncology Group (RTOG) guidelines. A total of 30 organs were delineated. Independently, 5 board-certified dosimetrists and 1 trainee then outlined the same organs. Metrics used to compare the agreement between the dosimetrists' contours and the gold contours included the Dice Similarity Coefficient (DSC), and a penalty function using distance to agreement. Based on these scores, dosimetrists were re-trained on those organs in which they did not receive a passing score, and they were subsequently re-tested. Results: Passing scores were achieved on 19 of 30 organs evaluated. These scores were correlated to organ volume. For organ volumes <8 cc, the average DSC was 0.61 vs organ volumes ≥8 cc, for which the average DSC was 0.91 (P=.005). Normal tissues that had the lowest scores included the lenses, optic nerves, chiasm, cochlea, and esophagus. Of the 11 organs that were considered for re-testing, 10 showed improvement in the average score, and statistically significant improvement was noted in more than half of these organs after education and re-assessment. Conclusions: The results of this study indicate the feasibility of applying the PDCA cycle to assess competence in the delineation of individual organs, and to identify areas for improvement. With testing, guidance, and re-evaluation, contouring consistency can be obtained across multiple dosimetrists. Our expectation is that continual quality improvement using the PDCA approach will ensure more accurate treatments and dose assessment in

Modification in oxidative processes in muscle tissues exposed to laser- and light-emitting diode radiation.

Science.gov (United States)

Monich, Victor A; Bavrina, Anna P; Malinovskaya, Svetlana L

2018-01-01

Exposure of living tissues to high-intensity red or near-infrared light can produce the oxidative stress effects both in the target zone and adjacent ones. The protein oxidative modification (POM) products can be used as reliable and early markers of oxidative stress. The contents of modified proteins in the investigated specimens can be evaluated by the 2,4-dinitrophenylhydrazine assay (the DNPH assay). Low-intensity red light is able to decrease the activity of oxidative processes and the DNPH assay data about the POM products in the biological tissues could show both an oxidative stress level and an efficiency of physical agent protection against the oxidative processes. Two control groups of white rats were irradiated by laser light, the first control group by red light and the second one by near-infrared radiation (NIR).Two experimental groups were consequently treated with laser and red low-level light-emitting diode radiation (LED). One of them was exposed to red laser light + LED and the other to NIR + LED. The fifth group was intact. Each group included ten animals. The effect of laser light was studied by methods of protein oxidative modifications. We measured levels of both induced and spontaneous POM products by the DNPH assay. The dramatic increase in levels of POM products in the control group samples when compared with the intact group data as well as the sharp decrease in the POM products in the experimental groups treated with LED low-level light were statistically significant (p ≤ 0.05). Exposure of skeletal muscles to high-intensity red and near-infrared laser light causes oxidative stress that continues not less than 3 days. The method of measurement of POM product contents by the DNPH assay is a reliable test of an oxidative process rate. Red low-intensity LED radiation can provide rehabilitation of skeletal muscle tissues treated with high-intensity laser light.

The Chernobyl Tissue Bank: integrating research on radiation-induced thyroid cancer.

Science.gov (United States)

Thomas, G A

2012-03-01

The only unequivocal radiological effect of the Chernobyl accident on human health is the increase in thyroid cancer in those exposed in childhood or early adolescence. Cancer is a complicated disease and it is unclear whether the mechanism by which radiation gives rise to cancer differs from that involved in the generation of cancers of the same type by other environmental stimuli. The Chernobyl Tissue Bank was established in response to the scientific interest in studying the molecular biology of thyroid cancer after Chernobyl to address this question. The project is supported by the governments of Ukraine and Russia, and financially supported (in total around US$3 million) by the European Commission, the National Cancer Institute of the USA and the Sasakawa Memorial Health Foundation of Japan. The project began collecting a variety of biological samples from patients on 1 October 1988, and has supplied material to 23 research projects in Japan, the USA and Europe. The establishment of the Chernobyl Tissue Bank has facilitated co-operation between these research projects and the combination of clinical and research data provides a paradigm for cancer research in the molecular biological age.

The Chernobyl Tissue Bank: integrating research on radiation-induced thyroid cancer

International Nuclear Information System (INIS)

Thomas, G A

2012-01-01

The only unequivocal radiological effect of the Chernobyl accident on human health is the increase in thyroid cancer in those exposed in childhood or early adolescence. Cancer is a complicated disease and it is unclear whether the mechanism by which radiation gives rise to cancer differs from that involved in the generation of cancers of the same type by other environmental stimuli. The Chernobyl Tissue Bank was established in response to the scientific interest in studying the molecular biology of thyroid cancer after Chernobyl to address this question. The project is supported by the governments of Ukraine and Russia, and financially supported (in total around US$3 million) by the European Commission, the National Cancer Institute of the USA and the Sasakawa Memorial Health Foundation of Japan. The project began collecting a variety of biological samples from patients on 1 October 1988, and has supplied material to 23 research projects in Japan, the USA and Europe. The establishment of the Chernobyl Tissue Bank has facilitated co-operation between these research projects and the combination of clinical and research data provides a paradigm for cancer research in the molecular biological age. (note)

The effect of ultraviolet-B radiation on gene expression and pigment composition in etiolated and green pea leaf tissue: UV-B-induced changes are gene-specific and dependent upon the developmental stage

International Nuclear Information System (INIS)

Jordan, B.R.; James, P.E.; Strid, A.; Anthony, R.G.

1994-01-01

The effect of ultraviolet-B radiation (UV-B: 280–320nm) on gene expression and pigment composition has been investigated in pea tissue at different stages of development. Pea (Pisum sativum L., cv. Feltham First) seedlings were grown for 17d and then exposed to supplementary UV-B radiation. Chlorophyll a per unit fresh weight decreased by more than 20% compared with control levels after exposure to UV-B radiation for 7d. In contrast, chlorophyll b content remained the same or increased slightly. Leaf protein biosynthesis, as determined by 35 S-methionine incorporation, was rapidly inhibited by UV-B radiation, although the steady-state levels of proteins were either unchanged or only slightly altered. RNA transcripts for the chlorophyll a/b binding protein (cab) were also rapidly reduced to low or even undetectable levels in the expanded third leaf or younger leaf bud tissue after exposure to UV-B radiation. In contrast, cab RNA transcripts were either low or undetectable in etiolated pea tissue, but increased substantially in light and during exposure to UV-B radiation. The cab RNA transcripts were still present at control levels in pea plants after 7d of greening under supplementary UV-B radiation or UV-B alone. The protein composition changed significantly over the 7d of greening, but no differences could be detected between the light treatments. The increase in chlorophyll content was slightly greater during de-etiolation under supplementary UV-B radiation than under control irradiance. Under UV-B radiation alone, chlorophyll was synthesized at a greatly reduced rate. Changes in protective pigments were also determined. Anthocyanins did not change in either etiolated or green tissue exposed to UV-B radiation. However, other flavonoids increased substantially in either tissue during exposure to light and UV-B radiation. The RNA levels for chalcone synthase were measured in green and etiolated tissue exposed to UV-B radiation. The chs RNA transcripts were

Health consequences of ionizing radiation exposure

International Nuclear Information System (INIS)

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

2004-01-01

article we examine the types of health effects associated with large acute exposures and with low dose rate chronic exposure. The biological effects of ionizing radiation to cell, tissue, organ and systems in humans will be outlined. (author)

Risk associated with occupational exposure to ionizing radiation kept in perspective

International Nuclear Information System (INIS)

Bonnell, J.A.; Harte, G.

1978-01-01

The risks associated with exposure to ionizing radiations are placed in perspective by a study of the natural incidence of those diseases in the United Kingdom that can be induced by radiation exposure. It is apparent that at ICRP recommended annual dose equivalent limits the small risks associated with exposure to ionizing radiations are acceptable, bearing in mind the obvious benefits that accrue from activities such as power production. This applies both to genetic and somatic diseases. (author)

Quantitative radiation dose-response relationships for normal tissues in man. II. Response of the salivary glands during radiotherapy

International Nuclear Information System (INIS)

Mossman, K.L.

1983-01-01

A quantitative dose-response curve for salivary gland function in patients during radiotherapy is presented. Salivary-function data used in this study were obtained from four previously published reports. All patients were treated with 60 Co teletherapy to the head and neck using conventional treatment techniques. Salivary dysfunction was determined at specific dose levels by comparing salivary flow rates before therapy with flow rates at specific dose intervals during radiotherapy up to a total dose of 6000 cGy. Fifty percent salivary dysfunction occurred after 1000 cGy and eighty percent dysfunction was observed by the end of the therapy course (6000 cGy). The salivary-function curve was also compared to the previously published dose-response curve for taste function. Comparisons of the two curves indicate that salivary dysfunction precedes taste loss and that the shapes of the dose-response curves are different. A new term, tissue tolerance ratio, defined as the ratio of responses of two tissues given the same radiation dose, was used to make the comparisons between gustatory and salivary gland tissue effects. Measurements of salivary gland function and analysis of dose-response curves may be useful in evaluating chemical modifiers of radiation response

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

DEFF Research Database (Denmark)

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

2010-01-01

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

Feijoeiro manteiga, planta-teste para os vírus de vira-cabeça e da necrose branca do fumo A bean variety useful as a local-lesion test plant for tomato spotted wilt and Brazilian tobacco streak viruses

Directory of Open Access Journals (Sweden)

A. S. Costa

1957-01-01

Full Text Available Entre cêrca de 200 variedades de feijoeiro ensaiadas, a Manteiga foi mais sensitiva aos vírus de vira-cabeça e da necrose branca, formando, nas fôlhas primárias, lesões locais adequadas para contagens. Com o vírus de vira-cabeça as lesões locais apareceram de 3 -6 dias após as inoculações, sob a forma de manchas cloróticas, às vezes com anéis necróticos; com o vírus da necrose branca as lesões se manifestaram em 1 - 4 dias, sob a forma de pontuações necróticas, pequenos anéis necróticos ou, em casos de certas estirpes do vírus, como pintas cloróticas. Feijoeiros com as fôlhas primárias tendo 2/3 de sua expansão ou mais desenvolvidas deram melhores resultados para o vírus de vira-cabeça; para o vírus da necrose branca os melhores resultados foram obtidos com fôlhas que tinham 2/3 ou ligeiramente menos de sua expansão total. O vírus de vira-cabeça não se tornou sistêmico em plantas inoculadas mecanicamente. A maioria das estirpes do vírus da necrose branca também não se tornou sistêmica em feijoeiros inoculados mecanicamente. Uma estirpe amarela deste tem a capacidade de se tornar sistêmica em feijoeiros sob determinadas condições. O sulfito de sódio em solução 0,0125 M, usado na extração do inóculo, aumentou ligeiramente o número de lesões formadas nas fôlhas do feijoeiro Manteiga pelo vírus de vira-cabeça; aumento consideravelmente maior foi obtido com a extração em presença de búfer de fosfato 0,1 M com pH 7, sendo êsse efeito atribuído a um aumento da sensitividade da planta-teste. A mistura de ambos causou aumento igual ou ligeiramente menor que o búfer só. Para o vírus da necrose branca a presença de sulfito de sódio 0,0125 M durante a extração aumentou consideravelmente o número de lesões, sendo esse efeito atribuído à diminuição na perda de atividade do vírus, devida à oxidação; o búfer sozinho ocasionou pequeno aumento em comparação com a testemunha, mas a

Proceedings of the Conference and Symposium Korean Association for Radiation Protection Spring Meeting 2017

Energy Technology Data Exchange (ETDEWEB)

NONE

2017-04-15

This proceedings contains articles of the Korean Association for Radiation Protection Spring Meeting, 2017. It was held on 13 April 2017 Gunsan Saemangeum Covention Center in Gunsan, Korea and subject of the Korean Association for Radiation Protection Spring Meeting 2017. This proceedings is comprised of 5 ssessions. The main topic titles of session are as follows: Radiation protection, Biotechnology of radiation, Radiation measurement and prevention, Radiation epidemiography.

Proceedings of the Conference and Symposium Korean Association for Radiation Protection Spring Meeting 2017

International Nuclear Information System (INIS)

2017-04-01

This proceedings contains articles of the Korean Association for Radiation Protection Spring Meeting, 2017. It was held on 13 April 2017 Gunsan Saemangeum Covention Center in Gunsan, Korea and subject of the Korean Association for Radiation Protection Spring Meeting 2017. This proceedings is comprised of 5 ssessions. The main topic titles of session are as follows: Radiation protection, Biotechnology of radiation, Radiation measurement and prevention, Radiation epidemiography.

Proceedings of the Conference and Symposium Korean Association for Radiation Protection Spring Meeting 2016

International Nuclear Information System (INIS)

2016-04-01

This proceedings contains articles of the Korean Association for Radiation Protection Spring Meeting, 2016. It was held on Apr. 6-8, 2016 Daemyung Resort in Byeonsan, Korea and subject of the Korean Association for Radiation Protection Spring Meeting 2016. This proceedings is comprised of 4 sessions. The main topic titles of session are as follows: Radiation protection, Biotechnology of radiation, Radiation Measurement, Radiation environment and prevention

BIOLOGICAL EFFECTS OF MICROWAVE RADIATION ON BRAIN TISSUE IN RATS

Directory of Open Access Journals (Sweden)

Boris Đinđić

2003-04-01

Full Text Available Exposure to microwave radiation induces multiple organ dysfunctions, especially in CNS.The aim of this work was investigation of biological effects of microwave radiation on rats' brain and determination of increased oxidative stress as a possible pathogenetic's mechanism.Wis tar rats 3 months old were divided in experimental (4 female and 4 male animal and control group (5 female and 4 male. This experimental group was constantly exposed to a magnetic field of 5 mG. We simulated using of mobile phones 30 min every day. The source of NIR emitted MF that was similar to mobile phones at 900 MHz. The rats were killed after 2 months. Biological effects were determined by observation of individual and collective behavior and body mass changes. Lipid per oxidation was determined by measuring quantity of malondialdehyde (MDA in brain homogenate.The animals in experimental group exposed to EMF showed les weight gain. The most important observations were changing of basic behavior models and expression of aggressive or panic behavior. The content of MDA in brain tissue is singificantly higher (1.42 times in rats exposed to electromagnetic fields (3,82±0.65 vs. control 2.69±0.42 nmol/mg proteins, p<0.01.Increased oxidative stress and lipid peroxidation after exposition in EM fields induced disorders of function and structure of brain.

Radiation-induced brain damage in children; Histological analysis of sequential tissue changes in 34 autopsy cases

Energy Technology Data Exchange (ETDEWEB)

Oi, Shizuo; Kokunai, Takashi; Ijichi, Akihiro; Matsumoto, Satoshi [Kobe Univ. (Japan). School of Medicine; Raimondi, A J

1990-01-01

The nature and sequence of the radiation-induced changes in the brain were studied postmortem in 34 children with glioma, 22 of whom underwent central nervous system radiation therapy. Twenty received whole-brain or whole-neuroaxis radiation at a total mean dosage of 4063 cGy. Brain tissue alternations were analyzed histologically by means of various staining methods, including immunohistochemical techniques. The histological features of irradiated brains were compared with those of non-irradiated brains. Microscopic findings included demyelination (seven cases), focal necrosis (six cases), cortical atrophy (four cases), endothelial proliferation (four cases), and telangiectatic vascular proliferation with vascular thickening and oozing of a thick fluid (one case). Such findings were rare in non-irradiated patients. Demyelination was observed earliest in a patient who died 5 months after radiation therapy and was more common after 9 months. Focal necrosis was first observed 9 months post-irradiation but was more advanced and extensive after 1 year. Calcified foci were found only after 60 months. Various vascular changes such as vascular thickening and thrombosis suggested ischemic insult to the brain as a late effect of radiation injury. The results of this study suggest that the immature brain may be more sensitive to radiation than is the adult brain, and that the manifestations of radiation-induced injury depend on the time elapsed after irradiation. (author).

Proceedings of 7th Symposium of the Croatian Radiation Protection Association

Energy Technology Data Exchange (ETDEWEB)

Barisic, D; Grahek, Z; Krajcar Bronic, I; Miljanic, S

2008-07-01

The 7th symposium of the Croatian Radiation Protection Association discussed the following topics: general topics; radiation dosimetry and instrumentation; biological effects of radiation; radiation protection in medicine; radioecology and radon. For each subject many investigations, experiments, examples and results are presented. International character of this symposium shows importance of these topics not only in region but world wide.

Proceedings of 7th Symposium of the Croatian Radiation Protection Association

International Nuclear Information System (INIS)

Barisic, D.; Grahek, Z.; Krajcar Bronic, I.; Miljanic, S.

2008-01-01

The 7th symposium of the Croatian Radiation Protection Association discussed the following topics: general topics; radiation dosimetry and instrumentation; biological effects of radiation; radiation protection in medicine; radioecology and radon. For each subject many investigations, experiments, examples and results are presented. International character of this symposium shows importance of these topics not only in region but world wide

Proceedings of 11th Symposium of the Croatian Radiation Protection Association

International Nuclear Information System (INIS)

Radolic, V.; Poje Sovilj, M.; Krajcar Bronic, I.

2017-01-01

The 11th symposium of the Croatian Radiation Protection Association discussed the following topics: ethics and culture in radiation protection; general topics; radiation protection and dosimetry in medicine; biological effects of radiation; instrumentation and measuring techniques; radioecology; public exposure; radon; non-ionising radiation. For each subject many investigations, experiments, examples and results are presented. International character of this symposium shows importance of these topics not only in region but world wide.

Tissue banking for management of nuclear casualties

International Nuclear Information System (INIS)

Singh, Rita

2014-01-01

The proliferation of nuclear material and technology has made the acquisition and adversarial use more probable than ever. Devastating medical consequences would follow a nuclear detonation due to the thermal, blast and radiation effects of the weapon. Atomic explosions at Hiroshima and Nagasaki demonstrated the human agonies on vast scale. A full range of medical modalities are required to decrease the morbidity and mortality as a result of the use of nuclear weapons. Biological tissues from human donor like bone, skin, amniotic membrane and other soft tissues can be used for repair or reconstruction of the injured part of the body. Tissues from human donor can be processed and banked for orthopaedic, spinal, trauma and other surgical procedures. Processed tissues can be provided by the tissue banks and can be of great assistance in the treatment of injuries due to the nuclear weapon. The use of allograft tissue avoids the donor site morbidity and reduces the operating time, expense and trauma associated with the acquisition of autografts. Further, allografts have the added advantage of being available in large quantities. This has led to a global increase in allogeneic transplantation and development of tissue banking. The aim of the tissue bank is to provide a wide range of processed biological tissues free from any transmissible disease, that help to restore the growth and function of the damaged tissues. Skin dressings or skin substitutes like allograft skin, xenograft skin and amniotic membrane can be used for the treatment of thermal burns and radiation induced skin injuries. Bone allografts can be used for reconstructive approaches to the skeletal system. Tissue banking would thus ensure health care to the military personnel and population following a nuclear detonation. (author)

Ultrasonic scalpel causes greater depth of soft tissue necrosis compared to monopolar electrocautery at standard power level settings in a pig model.

Science.gov (United States)

Homayounfar, Kia; Meis, Johanna; Jung, Klaus; Klosterhalfen, Bernd; Sprenger, Thilo; Conradi, Lena-Christin; Langer, Claus; Becker, Heinz

2012-02-23

Ultrasonic scalpel (UC) and monopolar electrocautery (ME) are common tools for soft tissue dissection. However, morphological data on the related tissue alteration are discordant. We developed an automatic device for standardized sample excision and compared quality and depth of morphological changes caused by UC and ME in a pig model. 100 tissue samples (5 × 3 cm) of the abdominal wall were excised in 16 pigs. Excisions were randomly performed manually or by using the self-constructed automatic device at standard power levels (60 W cutting in ME, level 5 in UC) for abdominal surgery. Quality of tissue alteration and depth of coagulation necrosis were examined histopathologically. Device (UC vs. ME) and mode (manually vs. automatic) effects were studied by two-way analysis of variance at a significance level of 5%. At the investigated power level settings UC and ME induced qualitatively similar coagulation necroses. Mean depth of necrosis was 450.4 ± 457.8 μm for manual UC and 553.5 ± 326.9 μm for automatic UC versus 149.0 ± 74.3 μm for manual ME and 257.6 ± 119.4 μm for automatic ME. Coagulation necrosis was significantly deeper (p power levels.

Patterns of Local Recurrence and Dose Fractionation of Adjuvant Radiation Therapy in 462 Patients With Soft Tissue Sarcoma of Extremity and Trunk Wall

International Nuclear Information System (INIS)

Jebsen, Nina L.; Engellau, Jacob; Engström, Katarina; Bauer, Henrik C.; Monge, Odd R.; Muren, Ludvig P.; Eide, Geir E.; Trovik, Clement S.; Bruland, Øyvind S.

2013-01-01

Purpose: To study the impact of dose fractionation of adjuvant radiation therapy (RT) on local recurrence (LR) and the relation of LR to radiation fields. Methods and Materials: LR rates were analyzed in 462 adult patients with soft tissue sarcoma who underwent surgical excision and adjuvant RT at five Scandinavian sarcoma centers from 1998 to 2009. Medical records were reviewed for dose fractionation parameters and to determine the location of the LR relative to the radiation portals. Results: Fifty-five of 462 patients developed a LR (11.9%). Negative prognostic factors included intralesional surgical margin (hazard ratio [HR]: 7.83, 95% confidence interval [CI]: 3.08-20.0), high malignancy grade (HR: 5.82, 95% CI: 1.31-25.8), age at diagnosis (HR per 10 years: 1.27, 95% CI: 1.03-1.56), and malignant peripheral nerve sheath tumor histological subtype (HR: 6.66, 95% CI: 2.56-17.3). RT dose was tailored to margin status. No correlation between RT dose and LR rate was found in multiple Cox regression analysis. The majority (65%) of LRs occurred within the primary RT volume. Conclusions: No significant dose–response effect of adjuvant RT was demonstrated. Interestingly, patients given 45-Gy accelerated RT (1.8 Gy twice daily/2.5 weeks) had the best local outcome. A total dose of 50 Gy in 25 fractions seemed adequate following wide margin surgery. The risk of LR was associated with histopathologic subtype, which should be included in the treatment algorithm of adjuvant RT in soft tissue sarcoma

Patterns of Local Recurrence and Dose Fractionation of Adjuvant Radiation Therapy in 462 Patients With Soft Tissue Sarcoma of Extremity and Trunk Wall

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Jebsen, Nina L., E-mail: nina.louise.jebsen@helse-bergen.no [Department of Clinical Medicine, Faculty of Medicine and Dentistry, University of Bergen, Bergen (Norway); Department of Oncology, Haukeland University Hospital, Bergen (Norway); Engellau, Jacob [Department of Oncology, Skåne University Hospital, Lund (Sweden); Engström, Katarina [Department of Oncology, Sahlgrenska University Hospital, Gothenburg (Sweden); Bauer, Henrik C. [Department of Molecular Medicine and Surgery, Section for Orthopaedics and Sports Medicine, Karolinska University Hospital, Karolinska Institute, Stockholm (Sweden); Monge, Odd R. [Department of Oncology, Haukeland University Hospital, Bergen (Norway); Muren, Ludvig P. [Department of Physics and Technology, University of Bergen, Bergen (Norway); Department of Medical Physics, Aarhus University and Aarhus University Hospital, Aarhus (Denmark); Eide, Geir E. [Centre for Clinical Research, Haukeland University Hospital, Bergen (Norway); Department of Public Health and Primary Health Care, University of Bergen, Bergen (Norway); Trovik, Clement S. [Department of Clinical Medicine, Faculty of Medicine and Dentistry, University of Bergen, Bergen (Norway); Department of Oncology, Haukeland University Hospital, Bergen (Norway); Bruland, Øyvind S. [Department of Oncology, The Norwegian Radium Hospital, Oslo University Hospital, Oslo (Norway); Institute of Clinical Medicine, University of Oslo, Oslo (Norway)

2013-08-01

Purpose: To study the impact of dose fractionation of adjuvant radiation therapy (RT) on local recurrence (LR) and the relation of LR to radiation fields. Methods and Materials: LR rates were analyzed in 462 adult patients with soft tissue sarcoma who underwent surgical excision and adjuvant RT at five Scandinavian sarcoma centers from 1998 to 2009. Medical records were reviewed for dose fractionation parameters and to determine the location of the LR relative to the radiation portals. Results: Fifty-five of 462 patients developed a LR (11.9%). Negative prognostic factors included intralesional surgical margin (hazard ratio [HR]: 7.83, 95% confidence interval [CI]: 3.08-20.0), high malignancy grade (HR: 5.82, 95% CI: 1.31-25.8), age at diagnosis (HR per 10 years: 1.27, 95% CI: 1.03-1.56), and malignant peripheral nerve sheath tumor histological subtype (HR: 6.66, 95% CI: 2.56-17.3). RT dose was tailored to margin status. No correlation between RT dose and LR rate was found in multiple Cox regression analysis. The majority (65%) of LRs occurred within the primary RT volume. Conclusions: No significant dose–response effect of adjuvant RT was demonstrated. Interestingly, patients given 45-Gy accelerated RT (1.8 Gy twice daily/2.5 weeks) had the best local outcome. A total dose of 50 Gy in 25 fractions seemed adequate following wide margin surgery. The risk of LR was associated with histopathologic subtype, which should be included in the treatment algorithm of adjuvant RT in soft tissue sarcoma.

Risk assessment from heterogeneous energy deposition in tissue, the problem of effects from low doses of ionizing radiation

International Nuclear Information System (INIS)

Feinendegen, L.E.; Booz, J.

1992-01-01

Low doses of ionizing radiation from external or internal sources cause heterogeneous distribution of energy deposition events in the exposed biological system. With the cell being the individual element of the tissue system, the fraction of cells hit, the dose received by the hit, and the biological response of the cell to the dose received eventually determine the effect in tissue. The hit cell may experience detriment, such as change in its DNA leading to a malignant transformation, or it may derive benefit in terms of an adaptive response such as a temporary improvement of DNA repair or temporary prevention of effects from intracellular radicals through enhanced radical detoxification. These responses are protective also to toxic substances that are generated during normal metabolism. Within a multicellular system the probability of detriment must be weighed against the probability of benefit through adaptive responses with protection against various toxic agents including those produced by normal metabolism. Because irradiation can principally induce both, detriment and adaptive responses, one type of affected cells may not be simply summed up at the expense of cells with other types of effects, in assessing risk to tissue. An inventory of various types of effects in the blood-forming system of mammals, even with large ranges of uncertainty, uncovers the possibility of benefit to the system from exposure to low doses of low-LET radiation. This experimental approach may complement epidemiological data on individuals exposed to low doses of ionizing radiation and may lead to a more rational appraisal of risk

Testicular cancer risk associated with occupational radiation exposure: a systematic literature review

Energy Technology Data Exchange (ETDEWEB)

Yousif, Lamya; Blettner, Maria; Hammer, Gael P; Zeeb, Hajo, E-mail: yousif@imbei.uni-mainz.d [Department of Epidemiology, Institute of Medical Biostatistics, Epidemiology and Informatics (IMBEI), University Medical Center, Johannes Gutenberg-University Mainz, Obere Zahlbacher Strasse 69, 55131 Mainz (Germany)

2010-09-15

Testicular cancer is a rare disease, affecting mainly young men aged 15-49. There have been some recent reports that it might be associated with radiation exposure. We have systematically reviewed this topic. English-language articles published between 1990 and 2008 studying the relationship between occupational radiation exposure and testicular cancer were included. Risk of bias was assessed using a modified version of the EPHPP checklist. For ionising radiation we subdivided study populations into occupational groups. No pooled analysis was performed due to the heterogeneity of studies. Seven case-control and 30 cohort studies were included in the review. For radiation workers, one incidence study showed a significant increase and four showed no effect. Eight mortality studies did not indicate an effect while four showed a non-significant increase. Incidence among persons with military exposure was not increased in two studies and non-significantly increased in another two. Among aircrew studies, one showed no effect against five with slight increases. Medical exposure studies showed no increases. For EMF exposure, three studies showed no effect, two reported a significant and four a non-significant increase in incidence. Overall, there was very limited evidence for associations between occupational ionising radiation and testicular cancer, while there were some positive associations for EMF. Testicular cancer mortality is generally low and was not associated with radiation. New incidence studies are recommended to investigate the association between radiation exposure and testicular cancer where exposure is better specified and individually estimated. (review)

Dose of radiation enhancement, using silver nanoparticles in a human tissue equivalent gel dosimeter.

Science.gov (United States)

Hassan, Muhammad; Waheed, Muhammad Mohsin; Anjum, Muhammad Naeem

2016-01-01

To quantify the radiation dose enhancement in a human tissue-equivalent polymer gel impregnated with silver nanoparticles. The case-control study was conducted at the Bahawalpur Institute of Nuclear Medicine and Oncology, Bahawalpur, Pakistan, in January 2014. Silver nanoparticles used in this study were prepared by wet chemical method. Polymer gel was prepared by known quantity of gelatine, methacrylic acid, ascorbic acid, copper sulphate pentahydrate, hydroquinone and water. Different concentrations of silver nanoparticles were added to the gel during its cooling process. The gel was cooled in six plastic vials of 50ml each. Two vials were used as a control sample while four vials were impregnated with silver nanoparticles. After 22 hours, the vials were irradiated with gamma rays by aCobalt-60 unit. Radiation enhancement was assessed by taking magnetic resonance images of the vials. The images were analysed using Image J software. The dose enhancement factor was 24.17% and 40.49% for 5Gy and 10Gy dose respectively. The dose enhancement factor for the gel impregnated with 0.10mM silver nanoparticles was 32.88% and 51.98% for 5Gy and 10Gy dose respectively. The impregnation of a tissue-equivalent gel with silver nanoparticles resulted in dose enhancement and this effect was magnified up to a certain level with the increase in concentration of silver nanoparticles.

Induction and Analysis of Bronchus-Associated Lymphoid Tissue.

Science.gov (United States)

Fleige, Henrike; Förster, Reinhold

2017-01-01

Bronchus-associated lymphoid tissue (BALT) forms spontaneously in the lung after pulmonary infection and has been identified as a highly organized lymphoid structure supporting the efficient priming of T cells in the lung. To explore the mechanisms and instructive signals controlling BALT neogenesis we used both, a single dose of vaccinia virus MVA and repeated inhalations of heat-inactivated Pseudomonas aeruginosa (P. aeruginosa). Intranasal administration of both pathogens induces highly organized BALT but distinct pathways and molecules are used to promote the development of BALT. Here, we describe the induction and phenotype of the distinct types of BALT as well as the immunofluorescence microscopy-based analysis of the induced lymphoid tissue in the lung.

Proceedings of the Conference and Symposium Korean Association for Radiation Protection Fall Meeting 2014

Energy Technology Data Exchange (ETDEWEB)

NONE

2014-11-15

This proceedings contains articles of the Korean Association for Radiation Protection Fall Meeting, 2014. It was held on Nov.19-21, 2014 in Jeju, Korea and subject of the Korean Association for Radiation Protection Fall Meeting 2014. This proceedings is comprised of 8 sessions. The main topic titles of session are as follows: Radiation protection 1, Medical treatment and Biology 1, Radiation measurement 1, Radiation environment and protection 1, Radiation protection 2, Medical treatment and Biology 2, Radiation Measurement 2, Radiation environment and protection 2.

Croatian Radiation Protection Association: From Yugoslavia to Europe

International Nuclear Information System (INIS)

Krajcar Bronic, I.; Miljanic, S.; Ranogajec-Komor, M.

2013-01-01

On the occasion of the fifty years of organised radiation protection activities at the area known as f ormer Yugoslavia , the professional activities and achievements in this field are presented in this paper. Croatian Radiation Protection Association (CRPA, www.hdzz.hr) was founded in 1979. In 1992 it became a regular member of the International Radiation Protection Association (IRPA). The main activities of CRPA members are: scientific research, participation in professional committees, intense cooperation in professional and scientific matters with the IRPA, other international bodies and Croatian scientific and professional societies, and related administrative work. CRPA members continue to provide advice and assistance to authorities, professional societies and individuals within their fields of expertise. Nine national symposia of CRPA with international participation were organized since 1991. All presentations were published as full papers in the Proceedings. CRPA participated in the organization of all IRPA Regional Congresses in Central Europe from 1993 (Obergurgl, Austria) till 2007 (Brasov, Romania). In 2001 CRPA hosted IRPA Regional Congress in Dubrovnik, Croatia. Members of CRPA are taking part in the organization of IRPA international congresses and in the work of IRPA General Assembly. CRPA has been actively involved in the informal meetings of European radiation protection societies since 2004 and organized their 6th meeting in Zagreb in 2009.(author)

ATM Polymorphisms Are Associated With Risk of Radiation-Induced Pneumonitis

International Nuclear Information System (INIS)

Zhang Li; Yang Ming; Bi Nan; Fang Mingjing; Sun Tong; Ji Wei; Tan Wen; Zhao Lujun; Yu Dianke; Lin Dongxin; Wang Luhua

2010-01-01

Purpose: Since the ataxia telangiectasia mutated (ATM) protein plays crucial roles in repair of double-stranded DNA breaks, control of cell cycle checkpoints, and radiosensitivity, we hypothesized that variations in this gene might be associated with radiation-induced pneumonitis (RP). Methods and Materials: A total of 253 lung cancer patients receiving thoracic irradiation between 2004 and 2006 were included in this study. Common Terminology Criteria for Adverse Events version 3.0 was used to grade RP. Five haplotype-tagging single nucleotide polymorphisms (SNPs) in the ATM gene were genotyped using DNA from blood lymphocytes. Hazard ratios (HRs) and 95% confidence intervals (CIs) of RP for genotypes were computed by the Cox model, adjusted for clinical factors. The function of the ATM SNP associated with RP was examined by biochemical assays. Results: During the median 22-month follow-up, 44 (17.4%) patients developed grade ≥ 2 RP. In multivariate Cox regression models adjusted for other clinical predictors, we found two ATM variants were independently associated with increased RP risk. They were an 111G > A) polymorphism (HR, 2.49; 95% CI, 1.07-5.80) and an ATM 126713G > A polymorphism (HR, 2.47; 95% CI, 1.16-5.28). Furthermore, genotype-dependent differences in ATM expression were demonstrated both in cell lines (p < 0.001) and in individual lung tissue samples (p = 0.003), which supported the results of the association study. Conclusions: Genetic polymorphisms of ATM are significantly associated with RP risk. These variants might exert their effect through regulation of ATM expression and serve as independent biomarkers for prediction of RP in patients treated with thoracic radiotherapy.

Radiation Safety Professional Certification Process in a Multi-Disciplinary Association

International Nuclear Information System (INIS)

Wilson, G.; Jones, P.; Ilson, R.

2004-01-01

There is no one set of criteria that defines the radiation safety professional in Canada. The many varied positions, from university and medical to industry and mining, define different qualifications to manage radiation safety programs. The national regulatory body has to assess many different qualifications when determining if an individual is acceptable to be approved for the role of radiation safety officer under any given licence. Some professional organizations specify education requirements and work experience as a prerequisite to certification. The education component specifies a degree of some type but does not identify specific courses or competencies within that degree. This could result in individuals with varying levels of radiation safety experience and training. The Canadian Radiation Protection Association (CRPA), responding to a need identified by the membership of the association, has initiated a process where the varying levels of knowledge of radiation safety can be addressed for radiation safety professionals. By identifying a core level set of radiation safety competencies, the basic level of radiation safety officer for smaller organizations can be met. By adding specialty areas, education can be pursued to define the more complex needs of larger organizations. This competency based process meets the needs of licensees who do not require highly trained health physicists in order to meet the licensing requirements and at the same time provides a stepping stone for those who wish to pursue a more specialized health physics option. (Author) 8 refs

Partial resistance to fruit necrosis associated to Colletotrichum spp. among arabic coffee genotypes

Directory of Open Access Journals (Sweden)

Gustavo Hiroshi Sera

2007-05-01

Full Text Available The aim of this study was to evaluate the resistance to fruit necrosis associated to Colletotrichum spp. in Coffea arabica L.. Twenty-two arabic coffee genotypes were performed in a randomized block design, with three replications and ten plants per plot. They were evaluated for the variables fruit necrosis, luminosity index inside of the plant canopy and fruits per productive nodes of the plants. There was genetic variability for the resistance to fruit necrosis. Different partial resistance levels, varying from highly susceptible (score = 3.89 to moderately resistant (score = 1.77 were observed. The genotypes that presented moderate resistance were the cultivars IPR-100, IPR-103, IPR-105 and IPR-108 and the coffee selection IAPAR-00023.Diferentes espécies de fungo do gênero têm sido associadas a perdas na cafeicultura brasileira. O objetivo deste trabalho foi avaliar a resistência à necrose de frutos associada ao Colletotrichum spp. em Coffea arabica L.. Vinte e dois genótipos de café foram avaliados no delineamento em blocos ao acaso com três repetições e dez plantas por parcela. As avaliações foram realizadas no IAPAR, Londrina, em janeiro de 2004 para as variáveis necrose de frutos, índice de luminosidade dentro da copa da planta e frutos por nó produtivo. Existe variabilidade genética em cafeeiros arábicos para a resistência à necrose de frutos. Foi observado diferentes níveis de resistência parcial, variando de altamente suscetível (nota = 3,89 a moderadamente resistente (nota = 1,77. Os genótipos que apresentaram moderada resistência foram as cultivares IPR-100, IPR-103, IPR-105 e IPR-108 e a seleção de café IAPAR-00023.

Long-term follow-up of bronchus-associated lymphoid tissue lymphomas (BALTOMA)

International Nuclear Information System (INIS)

Gaffke, G.; Jost, D.; Stroszcynski, C.; Puls, R.; Schlecht, I.; Felix, R.; Ludwig, W.D.; Hosten, N.

2002-01-01

Purpose: The purpose of this work was to describe the findings and the long term follow up of pathologically confirmed bronchus-associated lymphoid tissue lymphoma (BALTOMA) in 6 patients. Methods: CT examinations and conventional radiological examinations were reviewed and compared to describe typical radiological findings and patterns of pulmonary manifestations. It were described the number of lesions and characteristics like presence of airspace consolidation, ground-glass attenuation, bubble-like radio-lucencies, air bronchogram, bronchial dilatation, Infiltration and the long term behaviour of the manifestations. Results: Lesions with a positive air bronchogram, no infiltration of extrapulmonary tissue or extrapulmonary manifestations were revealed as typical findings. Only a slow or no progression of disease was shown in most patients over a term of up to twelve years. Conclusions: The lymphoma of the bronchus-associated lymphoid tissue of the lung is a rare tumor. A positive air bronchogram, a multiplicity of disease, bilateral lesions, a fibrotic transformation of the lung tissue and no growth or only a slow groth over al long term of observation are typical radiological findings. (orig.) [de

The Conjunctiva-Associated Lymphoid Tissue in Chronic Ocular Surface Diseases.

Science.gov (United States)

Mastropasqua, Rodolfo; Agnifili, Luca; Fasanella, Vincenzo; Nubile, Mario; Gnama, Agbeanda A; Falconio, Gennaro; Perri, Paolo; Di Staso, Silvio; Mariotti, Cesare

2017-08-01

Ocular surface diseases (OSDs) represent a widely investigated field of research given their growing incidence and the negative impact on quality of life. During OSDs, cytokines generated by damaged epithelia trigger and deregulate the lymphoid cells composing the eye-associated lymphoid tissues, inducing an immune-mediated chronic inflammation that amplifies and propagates the disease during time. The conjunctiva-associated lymphoid tissue (CALT), given its particular position that permits immune cells covering the cornea, might play a crucial role in the development of OSDs. Despite the recognized inflammatory role of mucosa-associated lymphoid tissues in other stations taking contact with the external environment (gut or bronchus), CALT did not gain the deserved consideration. In the last years, the diffusion of the in vivo confocal microscopy (IVCM) stimulated the interest to CALT, especially in dry eye, ocular allergy, and glaucoma. Though the initial stimuli were different, IVCM documented similar changes, represented by increased lymphoid cells within the diffuse layer, follicles and interfollicular spaces. These findings, which need to be validated by immunohistology, support the CALT stimulation during OSDs. However, while an involvement of the CALT in OSDs is hypothesizable, the exact role of this structure in their pathogenesis remains unclear and warrants further investigations.

Proceedings of 9th Symposium of the Croatian Radiation Protection Association

International Nuclear Information System (INIS)

Knezevic, Z.; Krajcar Bronic, I.; Majer, M.

2013-01-01

The 9th symposium of the Croatian Radiation Protection Association discussed the following topics: general topics; radiation dosimetry; public exposure; biological effects of radiation; radiation protection in medicine; radioecology and instrumentation and measuring techniques. For each subject many investigations, experiments, examples and results are presented. International character of this symposium shows importance of these topics not only in region but world wide.

Proceedings of the Conference and Symposium Korean Association for Radiation Protection Fall Meeting 2015

Energy Technology Data Exchange (ETDEWEB)

NONE

2015-10-15

This proceedings contains articles of the Korean Association for Radiation Protection Fall Meeting, 2015. It was held on Oct.23, 2015 Mayfield Hotel in Seoul, Korea and subject of the Korean Association for Radiation Protection Fall Meeting 2015. This proceedings is comprised of 8 sessions. The main topic titles of session are as follows: Radiation protection 1, Medical treatment and Biology 1, Radiation Measurement 1, Radiation environment and disasters prevention 1, Radiation protection 2, Medical treatment and Biology 2, Radiation Measurement 2, Radiation environment and disasters prevention 2.

Time-specific measurements of energy deposition from radiation fields in simulated sub-micron tissue volumes

International Nuclear Information System (INIS)

Famiano, M.A.

1997-01-01

A tissue-equivalent spherical proportional counter is used with a modified amplifier system to measure specific energy deposited from a uniform radiation field for short periods of time (∼1 micros to seconds) in order to extrapolate to dose in sub-micron tissue volumes. The energy deposited during these time intervals is compared to biological repair processes occurring within the same intervals after the initial energy deposition. The signal is integrated over a variable collection time which is adjusted with a square-wave pulse. Charge from particle passages is collected on the anode during the period in which the integrator is triggered, and the signal decays quickly to zero after the integrator feedback switch resets; the process repeats for every triggering pulse. Measurements of energy deposited from x rays, 137 Cs gamma rays, and electrons from a 90 Sr/ 90 Y source for various time intervals are taken. Spectral characteristics as a function of charge collection time are observed and frequency plots of specific energy and collection time-interval are presented. In addition, a threshold energy flux is selected for each radiation type at which the formation of radicals (based on current measurements) in mammalian cells equals the rate at which radicals are repaired

Cost-Effectiveness Analysis of Intensity Modulated Radiation Therapy Versus 3-Dimensional Conformal Radiation Therapy for Preoperative Treatment of Extremity Soft Tissue Sarcomas

Energy Technology Data Exchange (ETDEWEB)

Richard, Patrick, E-mail: patrjr@uw.edu [Department of Radiation Oncology, University of Washington, Seattle, Washington (United States); Phillips, Mark; Smith, Wade [Department of Radiation Oncology, University of Washington, Seattle, Washington (United States); Davidson, Darin [Department of Orthopedic Surgery, University of Washington, Seattle, Washington (United States); Kim, Edward; Kane, Gabrielle [Department of Radiation Oncology, University of Washington, Seattle, Washington (United States)

2016-07-01

Purpose: Create a cost-effectiveness model comparing preoperative intensity modulated radiation therapy (IMRT) versus 3-dimensional conformal radiation therapy (3DCRT) for extremity soft tissue sarcomas. Methods and Materials: Input parameters included 5-year local recurrence rates, rates of acute wound adverse events, and chronic toxicities (edema, fracture, joint stiffness, and fibrosis). Health-state utilities were used to calculate quality-adjusted life years (QALYs). Overall treatment costs per QALY or incremental cost-effectiveness ratio (ICER) were calculated. Roll-back analysis was performed using average costs and utilities to determine the baseline preferred radiation technique. One-way, 2-way, and probabilistic sensitivity analyses (PSA) were performed for input parameters with the largest impact on the ICER. Results: Overall treatment costs were $17,515.58 for 3DCRT compared with $22,920.51 for IMRT. The effectiveness was higher for IMRT (3.68 QALYs) than for 3DCRT (3.35 QALYs). The baseline ICER for IMRT was $16,842.75/QALY, making it the preferable treatment. The ICER was most sensitive to the probability of local recurrence, upfront radiation costs, local recurrence costs, certain utilities (no toxicity/no recurrence, grade 1 toxicity/no local recurrence, grade 4 toxicity/no local recurrence), and life expectancy. Dominance patterns emerged when the cost of 3DCRT exceeded $15,532.05 (IMRT dominates) or the life expectancy was under 1.68 years (3DCRT dominates). Furthermore, preference patterns changed based on the rate of local recurrence (threshold: 13%). The PSA results demonstrated that IMRT was the preferred cost-effective technique for 64% of trials compared with 36% for 3DCRT. Conclusions: Based on our model, IMRT is the preferred technique by lowering rates of local recurrence, severe toxicities, and improving QALYs. From a third-party payer perspective, IMRT should be a supported approach for extremity soft tissue sarcomas.

Cost-Effectiveness Analysis of Intensity Modulated Radiation Therapy Versus 3-Dimensional Conformal Radiation Therapy for Preoperative Treatment of Extremity Soft Tissue Sarcomas

International Nuclear Information System (INIS)

Richard, Patrick; Phillips, Mark; Smith, Wade; Davidson, Darin; Kim, Edward; Kane, Gabrielle

2016-01-01

Purpose: Create a cost-effectiveness model comparing preoperative intensity modulated radiation therapy (IMRT) versus 3-dimensional conformal radiation therapy (3DCRT) for extremity soft tissue sarcomas. Methods and Materials: Input parameters included 5-year local recurrence rates, rates of acute wound adverse events, and chronic toxicities (edema, fracture, joint stiffness, and fibrosis). Health-state utilities were used to calculate quality-adjusted life years (QALYs). Overall treatment costs per QALY or incremental cost-effectiveness ratio (ICER) were calculated. Roll-back analysis was performed using average costs and utilities to determine the baseline preferred radiation technique. One-way, 2-way, and probabilistic sensitivity analyses (PSA) were performed for input parameters with the largest impact on the ICER. Results: Overall treatment costs were $17,515.58 for 3DCRT compared with $22,920.51 for IMRT. The effectiveness was higher for IMRT (3.68 QALYs) than for 3DCRT (3.35 QALYs). The baseline ICER for IMRT was $16,842.75/QALY, making it the preferable treatment. The ICER was most sensitive to the probability of local recurrence, upfront radiation costs, local recurrence costs, certain utilities (no toxicity/no recurrence, grade 1 toxicity/no local recurrence, grade 4 toxicity/no local recurrence), and life expectancy. Dominance patterns emerged when the cost of 3DCRT exceeded $15,532.05 (IMRT dominates) or the life expectancy was under 1.68 years (3DCRT dominates). Furthermore, preference patterns changed based on the rate of local recurrence (threshold: 13%). The PSA results demonstrated that IMRT was the preferred cost-effective technique for 64% of trials compared with 36% for 3DCRT. Conclusions: Based on our model, IMRT is the preferred technique by lowering rates of local recurrence, severe toxicities, and improving QALYs. From a third-party payer perspective, IMRT should be a supported approach for extremity soft tissue sarcomas.

Identification of radiation response genes and proteins from mouse pulmonary tissues after high-dose per fraction irradiation of limited lung volumes.

Science.gov (United States)

Jin, Hee; Jeon, Seulgi; Kang, Ga-Young; Lee, Hae-June; Cho, Jaeho; Lee, Yun-Sil

2017-02-01

The molecular effects of focal exposure of limited lung volumes to high-dose per fraction irradiation (HDFR) such as stereotactic body radiotherapy (SBRT) have not been fully characterized. In this study, we used such an irradiation system and identified the genes and proteins after HDFR to mouse lung, similar to those associated with human therapy. High focal radiation (90 Gy) was applied to a 3-mm volume of the left lung of C57BL6 mice using a small-animal stereotactic irradiator. As well as histological examination for lungs, a cDNA micro array using irradiated lung tissues and a protein array of sera were performed until 4 weeks after irradiation, and radiation-responsive genes and proteins were identified. For comparison, the long-term effects (12 months) of 20 Gy radiation wide-field dose to the left lung were also investigated. The genes ermap, epb4.2, cd200r3 (up regulation) and krt15, hoxc4, gdf2, cst9, cidec, and bnc1 (down-regulation) and the proteins of AIF, laminin, bNOS, HSP27, β-amyloid (upregulation), and calponin (downregulation) were identified as being responsive to 90 Gy HDFR. The gdf2, cst9, and cidec genes also responded to 20 Gy, suggesting that they are universal responsive genes in irradiated lungs. No universal proteins were identified in both 90 Gy and 20 Gy. Calponin, which was downregulated in protein antibody array analysis, showed a similar pattern in microarray data, suggesting a possible HDFR responsive serum biomarker that reflects gene alteration of irradiated lung tissue. These genes and proteins also responded to the lower doses of 20 Gy and 50 Gy HDFR. These results suggest that identified candidate genes and proteins are HDFR-specifically expressed in lung damage induced by HDFR relevant to SBRT in humans.

Determination of Radiation Absorbed Dose to Primary Liver Tumors and Normal Liver Tissue Using Post Radioembolization 90Y PET

Directory of Open Access Journals (Sweden)

Shyam Mohan Srinivas

2014-10-01

Full Text Available Background: Radioembolization with Yttrium-90 (90Y microspheres is becoming a more widely used transcatheter treatment for unresectable hepatocellular carcinoma (HCC. Using post-treatment 90Y PET/CT scans,the distribution of microspheres within the liver can be determined and quantitatively assessesed . We studied the radiation dose of 90Y delivered to liver and treated tumors.Methods: This retrospective study of 56 patients with HCC, including analysis of 98 liver tumors, measured and correlated the dose of radiation delivered to liver tumors and normal liver tissue using glass microspheres (TheraSpheres® to the frequency of complications with mRECIST. 90Y PET/CT and triphasic liver CT scans were used to contour treated tumor and normal liver regions and determine their respective activity concentrations. An absorbed dose factor was used to convert the measured activity concentration (Bq/mL to an absorbed dose (Gy.Results: The 98 studied tumors received a mean dose of 169 Gy (mode 90-120 Gy;range 0-570 Gy. Tumor response by mRECIST criteria was performed for 48 tumors that had follow up scans. There were 21 responders (mean dose 215 Gy and 27 nonresponders (mean dose 167 Gy. The association between mean tumor absorbed dose and response suggests a trend but did not reach statistical significance (p=0.099. Normal liver tissue received a mean dose of 67 Gy (mode 60-70 Gy; range 10-120 Gy. There was a statistically significant association between absorbed dose to normal liver and the presence of two or more severe complications (p=0.036.Conclusion: Our cohort of patients showed a possible dose response trend for the tumors. Collateral dose to normal liver is nontrivial and can have clinical implications. These methods help us understand whether patient adverse events, treatment success, or treatment failure can be attributed to the dose which the tumor or normal liver received.

Statistical associations between radiation exposure and the clinical examination data of Japanese radiology technicians

International Nuclear Information System (INIS)

Kondo, Hisayoshi; Okumura, Yutaka; Aoyama, Takashi; Sugahara, Tsutomu; Hashimoto, Tetsuaki; Yamamoto, Yoichi.

1995-01-01

The associations between occupational irradiation, cigarette smoking, alcohol drinking and clinical examination data were investigated in Japanese male radiology technicians. The number of investigated examination items was 35, including 29 biochemical serum test, four hematological tests and systolic and diastolic blood pressure. The associations with each factor were evaluated using the multiple linear regression model. As single factors, radiation associated with urea nitrogen, alkaline phosphatase, monoamine oxidase and leukocyte count (four items), smoking associated with albumin-globulin index, zinc sulfate turbidity test, urea nitrogen, creatinine, neutral fat, amylase, serum iron, leukocyte count, hemoglobin and hematocrit (10 items), and drinking associated with creatinine, uric acid, glutamate oxaloacetate transaminase, leucine aminopeptidase, alkaline phosphatase and erythrocyte count (six items). As synergistic factors, the combination of radiation and smoking associated with nine items, radiation and drinking 10 items, smoking and drinking four items, and radiation, smoking and drinking two items. These results suggested that the number of items which radiation associated as single-factor were less than that of smoking and of drinking, however suggested that associations between radiation and examination data was synergistic when combined with smoking or drinking. (author)

Statistical associations between radiation exposure and the clinical examination data of Japanese radiology technicians

Energy Technology Data Exchange (ETDEWEB)

Kondo, Hisayoshi; Okumura, Yutaka [Nagasaki Univ. (Japan). School of Medicine; Aoyama, Takashi; Sugahara, Tsutomu; Hashimoto, Tetsuaki; Yamamoto, Yoichi

1995-06-01

The associations between occupational irradiation, cigarette smoking, alcohol drinking and clinical examination data were investigated in Japanese male radiology technicians. The number of investigated examination items was 35, including 29 biochemical serum test, four hematological tests and systolic and diastolic blood pressure. The associations with each factor were evaluated using the multiple linear regression model. As single factors, radiation associated with urea nitrogen, alkaline phosphatase, monoamine oxidase and leukocyte count (four items), smoking associated with albumin-globulin index, zinc sulfate turbidity test, urea nitrogen, creatinine, neutral fat, amylase, serum iron, leukocyte count, hemoglobin and hematocrit (10 items), and drinking associated with creatinine, uric acid, glutamate oxaloacetate transaminase, leucine aminopeptidase, alkaline phosphatase and erythrocyte count (six items). As synergistic factors, the combination of radiation and smoking associated with nine items, radiation and drinking 10 items, smoking and drinking four items, and radiation, smoking and drinking two items. These results suggested that the number of items which radiation associated as single-factor were less than that of smoking and of drinking, however suggested that associations between radiation and examination data was synergistic when combined with smoking or drinking. (author).

External Beam Radiation Therapy and Abiraterone in Men With Localized Prostate Cancer: Safety and Effect on Tissue Androgens

International Nuclear Information System (INIS)

Cho, Eunpi; Mostaghel, Elahe A.; Russell, Kenneth J.; Liao, Jay J.; Konodi, Mark A.; Kurland, Brenda F.; Marck, Brett T.; Matsumoto, Alvin M.; Dalkin, Bruce L.; Montgomery, R. Bruce

2015-01-01

Purpose: Optimizing androgen suppression may provide better control of localized prostate cancer (PCa). Numerous trials have supported the benefit of combining androgen deprivation therapy with definitive radiation therapy in men with locally advanced or high-grade disease. Addition of abiraterone to luteinizing hormone-releasing hormone agonist (LHRHa) with radiation has not been reported. We examined the safety of this combination as well as its impact on androgen suppression. Methods and Materials: A prospective, phase 2 study was conducted in men with localized PCa treated with 6 months of neoadjuvant and concurrent abiraterone with LHRHa and radiation. Duration of adjuvant LHRHa was at the discretion of the treating clinician. Prostate biopsy assays were obtained prior to the start of therapy and prior to radiation. Sera and tissue androgen levels were measured by liquid chromatography-tandem mass spectrometry. Results: A total of 22 men with intermediate- (n=3) and high-risk PCa (n=19) received study therapy. Sixteen men completed the intended course of abiraterone, and 19 men completed planned radiation to 77.4 to 81 Gy. Radiation to pelvic nodes was administered in 20 men. The following grade 3 toxicities were reported: lymphopenia (14 patients), fatigue (1 patient), transaminitis (2 patients), hypertension (2 patients), and hypokalemia (1 patient). There were no grade 4 toxicities. All 21 men who complied with at least 3 months of abiraterone therapy had a preradiation prostate-specific antigen (PSA) concentration nadir of <0.3 ng/mL. Median levels of tissue androgen downstream of CYP17A were significantly suppressed after treatment with abiraterone, and upstream steroids were increased. At median follow-up of 21 months (range: 3-37 months), only 1 patient (who had discontinued abiraterone at 3 months) had biochemical relapse. Conclusions: Addition of abiraterone to LHRHa with radiation is safe and achieves effective prostatic androgen suppression

External Beam Radiation Therapy and Abiraterone in Men With Localized Prostate Cancer: Safety and Effect on Tissue Androgens

Energy Technology Data Exchange (ETDEWEB)

Cho, Eunpi [University of Washington School of Medicine, Seattle, Washington (United States); Fred Hutchinson Cancer Research Center, Seattle, Washington (United States); Mostaghel, Elahe A. [Fred Hutchinson Cancer Research Center, Seattle, Washington (United States); Russell, Kenneth J.; Liao, Jay J.; Konodi, Mark A. [University of Washington School of Medicine, Seattle, Washington (United States); Kurland, Brenda F. [University of Pittsburgh, Pittsburgh, Pennsylvania (United States); Marck, Brett T. [Veterans Affairs Puget Sound Health Care System, Seattle, Washington (United States); Matsumoto, Alvin M. [University of Washington School of Medicine, Seattle, Washington (United States); Veterans Affairs Puget Sound Health Care System, Seattle, Washington (United States); Dalkin, Bruce L. [University of Washington School of Medicine, Seattle, Washington (United States); Montgomery, R. Bruce, E-mail: rbmontgo@uw.edu [University of Washington School of Medicine, Seattle, Washington (United States)

2015-06-01

Purpose: Optimizing androgen suppression may provide better control of localized prostate cancer (PCa). Numerous trials have supported the benefit of combining androgen deprivation therapy with definitive radiation therapy in men with locally advanced or high-grade disease. Addition of abiraterone to luteinizing hormone-releasing hormone agonist (LHRHa) with radiation has not been reported. We examined the safety of this combination as well as its impact on androgen suppression. Methods and Materials: A prospective, phase 2 study was conducted in men with localized PCa treated with 6 months of neoadjuvant and concurrent abiraterone with LHRHa and radiation. Duration of adjuvant LHRHa was at the discretion of the treating clinician. Prostate biopsy assays were obtained prior to the start of therapy and prior to radiation. Sera and tissue androgen levels were measured by liquid chromatography-tandem mass spectrometry. Results: A total of 22 men with intermediate- (n=3) and high-risk PCa (n=19) received study therapy. Sixteen men completed the intended course of abiraterone, and 19 men completed planned radiation to 77.4 to 81 Gy. Radiation to pelvic nodes was administered in 20 men. The following grade 3 toxicities were reported: lymphopenia (14 patients), fatigue (1 patient), transaminitis (2 patients), hypertension (2 patients), and hypokalemia (1 patient). There were no grade 4 toxicities. All 21 men who complied with at least 3 months of abiraterone therapy had a preradiation prostate-specific antigen (PSA) concentration nadir of <0.3 ng/mL. Median levels of tissue androgen downstream of CYP17A were significantly suppressed after treatment with abiraterone, and upstream steroids were increased. At median follow-up of 21 months (range: 3-37 months), only 1 patient (who had discontinued abiraterone at 3 months) had biochemical relapse. Conclusions: Addition of abiraterone to LHRHa with radiation is safe and achieves effective prostatic androgen suppression

Tissue Pharmacologic and Virologic Determinants of Duodenal and Rectal Gastrointestinal-Associated Lymphoid Tissue Immune Reconstitution in HIV-Infected Patients Initiating Antiretroviral Therapy.

Science.gov (United States)

Asmuth, David M; Thompson, Corbin G; Chun, Tae-Wook; Ma, Zhong-Min; Mann, Surinder; Sainz, Talia; Serrano-Villar, Sergio; Utay, Netanya S; Garcia, Juan Carlos; Troia-Cancio, Paolo; Pollard, Richard B; Miller, Christopher J; Landay, Alan; Kashuba, Angela D

2017-10-17

Plasma, duodenal, and rectal tissue antiretroviral therapy (ART) drug concentrations, human immunodeficiency virus (HIV) RNA and HIV DNA copy numbers, and recovery of mucosal immunity were measured before and 9 months after initiation of 3 different ART regimens in 26 subjects. Plasma and tissue HIV RNA correlated at baseline and when 9-month declines were compared, suggesting that these compartments are tightly associated. Antiretroviral tissue:blood penetration ratios were above the 50% inhibitory concentration values in almost 100% of cases. There were no correlations between drug concentrations and HIV DNA/RNA. Importantly, no evidence was found for residual viral replication or deficient tissue drug penetration to account for delayed gastrointestinal-associated lymphoid tissue immune recovery. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.

Oral soft tissue disorders are associated with gastroesophageal reflux disease: retrospective study.

Science.gov (United States)

Watanabe, Masaaki; Nakatani, Eiji; Yoshikawa, Hiroo; Kanno, Takahiro; Nariai, Yoshiki; Yoshino, Aya; Vieth, Michael; Kinoshita, Yoshikazu; Sekine, Joji

2017-08-07

Dental erosion (DE), one of oral hard tissue diseases, is one of the extraoesophageal symptoms defined as the Montreal Definition and Classification of gastroesophageal reflux disease (GERD). However, no study evaluated the relationship between GERD and oral soft tissues. We hypothesized that oral soft tissue disorders (OSTDs) would be related to GERD. The study aimed to investigate the association OSTDs and GERD. GERD patients (105 cases), older and younger controls (25 cases each) were retrospectively examined for oral symptoms, salivary flow volume (Saxon test), swallowing function (repetitive saliva swallowing test [RSST]), teeth (decayed, missing, and filled [DMF] indices), and soft tissues (as evaluation of OSTDs, gingivitis; papillary, marginal, and attached [PMA] gingival indexes, simplified oral hygiene indices [OHI-S], and inflammatory oral mucosal regions). Clinical histories, which included body mass index [BMI], the existence of alcohol and tobacco use, and bruxism, were also investigated. A P value of bruxism, as an exacerbation factor of periodontal disease, in the GERD patients was significantly more frequent than in either control group (P = 0.041). OSTDs were associated with GERD, which was similar to the association between DE and GERD.

Intraoperative Radiation Therapy for Locally Advanced and Recurrent Soft-Tissue Sarcomas in Adults

International Nuclear Information System (INIS)

Tran, Phuoc T.; Hara, Wendy; Su Zheng; Lin, H. Jill; Bendapudi, Pavan K.; Norton, Jeffrey; Teng, Nelson; King, Christopher R.; Kapp, Daniel S.

2008-01-01

Purpose: To analyze the outcomes of and identify prognostic factors for patients treated with surgery and intraoperative radiotherapy (IORT) for locally advanced and recurrent soft-tissue sarcoma in adults from a single institution. Methods and Materials: We retrospectively reviewed 50 consecutive patients treated with IORT to 62 sites of disease. Primary sites included retroperitoneum-pelvis (78%), extremity (8%), and other (14%). Seventy percent of patients had recurrent disease failing prior surgery (70%) and/or radiation (32%). Mean disease-free interval (DFI) before IORT was 1.9 years (range, 2 weeks-5.4 years). The IORT was delivered with orthovoltage X-rays using individually sized beveled cone applicators. Clinical characteristics were as follows: mean tumor size, 10 cm (range, 1-25 cm); high-grade histologic subtype (72%); and mean dose, 1,159 cGy (range, 600-1,600 cGy). Postoperative radiation or chemotherapy was administered to 37% of IORT Sites and 32% of patients, respectively. Outcomes measured were infield control (IFC), locoregional control (LRC), distant metastasis-free survival (DMFS), disease-specific survival (DSS), and treatment-related complications. Mean and median follow-up of alive patients were 59 and 35 months, respectively. Results: Kaplan-Meier 5-year IFC, LRC, DMFS, and DSS probabilities for the entire group were 55%, 26%, 51%, and 25%, respectively. Prognostic factors found to be significant (p < 0.05) on multivariate analysis were prior DFI and tumor size for LRC, extremity location and leiomyosarcoma histologic subtype for DMFS, and prior DFI for DSS. Our cohort had five Grade 3/4 complications associated with treatment or a 5-year Kaplan-Meier Grade 3/4 complication-free survival rate of 85%. Conclusions: IORT after tumor reductive surgery is well tolerated and seems to confer IFC in carefully selected patients

Radiation sickness

Science.gov (United States)

... exposure to ionizing radiation. There are two main types of radiation: nonionizing and ionizing. Nonionizing radiation comes in the form of light, radio waves, microwaves and radar. These forms usually don't cause tissue damage. ...

Reduced H3K27me3 expression in radiation-associated angiosarcoma of the breast

DEFF Research Database (Denmark)

Mentzel, Thomas; Kiss, Katalin

2018-01-01

The diagnosis of radiation-associated angiosarcoma is challenging and there are overlapping clinicopathological features between radiation-associated benign, atypical and malignant vascular lesions. It has been shown convincingly, that the majority of radiation-associated angiosarcomas are charac...

Breast reconstruction and post-mastectomy radiation practice

International Nuclear Information System (INIS)

Chen, Susie A; Hiley, Crispin; Nickleach, Dana; Petsuksiri, Janjira; Andic, Fundagul; Riesterer, Oliver; Switchenko, Jeffrey M; Torres, Mylin A

2013-01-01

The goal of this study was to explore the perspectives and practice of radiation oncologists who treat breast cancer patients who have had breast reconstruction. In 2010, an original electronic survey was sent to all physician members of the American Society of Radiation Oncology, National Cancer Research Institute-Breast Cancer Studies Group in the United Kingdom, Thai Society of Therapeutic Radiology and Oncology, Swiss Society of Radiation Oncology, and Turkish Radiation Oncology Society. We identified factors associated with radiation oncologists who treat breast cancer patients with reconstruction performed prior to radiation and obtained information regarding radiation management of the breast reconstruction. 358 radiation oncologists responded, and 60% of the physicians were from the United States. While 64% of participants agree or strongly agree that breast image affects a woman’s quality of life during radiation, 57% feel that reconstruction challenges their ability to deliver effective breast radiation. Compared with other countries, treatment within the United States was associated with a high reconstruction rate (>/= 50% of mastectomy patients) prior to radiation (p < 0.05). Delayed-immediate reconstruction with a temporary tissue expander was more common in the United States than in other countries (52% vs. 23%, p = 0.01). Among physicians who treat patients with tissue expanders, the majority (60%) prefer a moderately inflated implant with 150-250 cc of fluid rather than a completely deflated (13%) or inflated expander (28%) during radiation. Among radiation oncologists who treat reconstructions, 49% never use bolus and 40% never boost a breast reconstruction. United States physicians were more likely than physicians from other countries to boost or bolus the reconstruction irrespective of the type of reconstruction seen in their clinic patients (p < 0.01). Great variation in practice is evident from our study of radiation treatment for breast

The role of pyrimidine and water as underlying molecular constituents for describing radiation damage in living tissue: A comparative study

Energy Technology Data Exchange (ETDEWEB)

Fuss, M. C.; Ellis-Gibbings, L. [Instituto de Física Fundamental, Consejo Superior de Investigaciones Científicas (CSIC), Serrano 113-bis, 28006 Madrid (Spain); Jones, D. B. [School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide, South Australia 5001 (Australia); Brunger, M. J. [School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide, South Australia 5001 (Australia); Institute of Mathematical Sciences, University of Malaya, 50603 Kuala Lumpur (Malaysia); Blanco, F. [Departamento de Física Atómica, Molecular y Nuclear, Universidad Complutense de Madrid, Avenida Complutense, 28040 Madrid (Spain); Muñoz, A. [Centro de Investigaciones Energéticas Medioambientales y Tecnológicas, Avenida Complutense 22, 28040 Madrid (Spain); Limão-Vieira, P. [School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide, South Australia 5001 (Australia); Laboratório de Colisões Atómicas e Moleculares, CEFITEC, Departamento de Física, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal); García, G., E-mail: g.garcia@csic.es [Instituto de Física Fundamental, Consejo Superior de Investigaciones Científicas (CSIC), Serrano 113-bis, 28006 Madrid (Spain); Centre for Medical Radiation Physics, University of Wollongong, Wollongong, NSW 2522 (Australia)

2015-06-07

Water is often used as the medium for characterizing the effects of radiation on living tissue. However, in this study, charged-particle track simulations are employed to quantify the induced physicochemical and potential biological implications when a primary ionising particle with energy 10 keV strikes a medium made up entirely of water or pyrimidine. Note that pyrimidine was chosen as the DNA/RNA bases cytosine, thymine, and uracil can be considered pyrimidine derivatives. This study aims to assess the influence of the choice of medium on the charged-particle transport, and identify how appropriate it is to use water as the default medium to describe the effects of ionising radiation on living tissue. Based on the respective electron interaction cross sections, we provide a model, which allows the study of radiation effects not only in terms of energy deposition (absorbed dose and stopping power) but also in terms of the number of induced molecular processes. Results of these parameters for water and pyrimidine are presented and compared.

Association between traumatic bone marrow abnormalities of the knee, the trauma mechanism and associated soft-tissue knee injuries

Energy Technology Data Exchange (ETDEWEB)

Berger, Nicole [University Hospital Zurich, Institute of Diagnostic and Interventional Radiology, Zurich (Switzerland); University of Zurich, Department of Forensic Medicine and Radiology, Institute of Forensic Medicine, Zurich (Switzerland); Andreisek, Gustav; Karer, Anissja T.; Manoliu, Andrei; Ulbrich, Erika J. [University Hospital Zurich, Institute of Diagnostic and Interventional Radiology, Zurich (Switzerland); Bouaicha, Samy [University Hospital Zurich, Department of Trauma Surgery, Zurich (Switzerland); Naraghi, Ali [University of Toronto, Department of Medical Imaging, Mount Sinai Hospital and the University Health Network, Toronto, ON (Canada); Seifert, Burkhardt [University of Zurich, Epidemiology, Biostatistics and Prevention Institute, Department of Biostatistics, Zurich (Switzerland)

2017-01-15

To determine the association between traumatic bone marrow abnormalities, the knee injury mechanism, and associated soft tissue injuries in a larger cohort than those in the published literature. Retrospective study including 220 patients with traumatic knee injuries. Knee MRIs were evaluated for trauma mechanism, soft tissue injury, and the location of bone marrow abnormalities. The locations of the abnormalities were correlated with trauma mechanisms and soft tissue injuries using the chi-square test with Bonferroni correction. One hundred and forty-four valgus injuries, 39 pivot shift injuries, 25 lateral patellar dislocations, 8 hyperextensions, and 4 dashboard injuries were included. Valgus and pivot shift injuries showed traumatic bone marrow abnormalities in the posterolateral regions of the tibia. Abnormalities after patellar dislocation were found in the anterolateral and centrolateral femur and patella. Hyperextension injuries were associated with abnormalities in almost all regions, and dashboard injuries were associated with changes in the anterior regions of the tibia and femur. Our study provides evidence of associations between traumatic bone marrow abnormality patterns and different trauma mechanisms in acute knee injury, and reveals some overlap, especially of the two most common trauma mechanisms (valgus and pivot shift), in a large patient cohort. (orig.)

Association between traumatic bone marrow abnormalities of the knee, the trauma mechanism and associated soft-tissue knee injuries

International Nuclear Information System (INIS)

Berger, Nicole; Andreisek, Gustav; Karer, Anissja T.; Manoliu, Andrei; Ulbrich, Erika J.; Bouaicha, Samy; Naraghi, Ali; Seifert, Burkhardt

2017-01-01

To determine the association between traumatic bone marrow abnormalities, the knee injury mechanism, and associated soft tissue injuries in a larger cohort than those in the published literature. Retrospective study including 220 patients with traumatic knee injuries. Knee MRIs were evaluated for trauma mechanism, soft tissue injury, and the location of bone marrow abnormalities. The locations of the abnormalities were correlated with trauma mechanisms and soft tissue injuries using the chi-square test with Bonferroni correction. One hundred and forty-four valgus injuries, 39 pivot shift injuries, 25 lateral patellar dislocations, 8 hyperextensions, and 4 dashboard injuries were included. Valgus and pivot shift injuries showed traumatic bone marrow abnormalities in the posterolateral regions of the tibia. Abnormalities after patellar dislocation were found in the anterolateral and centrolateral femur and patella. Hyperextension injuries were associated with abnormalities in almost all regions, and dashboard injuries were associated with changes in the anterior regions of the tibia and femur. Our study provides evidence of associations between traumatic bone marrow abnormality patterns and different trauma mechanisms in acute knee injury, and reveals some overlap, especially of the two most common trauma mechanisms (valgus and pivot shift), in a large patient cohort. (orig.)

Role of Omega 3 fatty acids on radiation-induced oxidative and structural damage in different tissues of male albino rats

International Nuclear Information System (INIS)

Rezk, R.G.; Abou Zaid, N.M.; Ahmed, A. G.

2011-01-01

Omega-3 fatty acids play a critical role in the development and function of the reproductive and central nervous systems. The aim of this study is to evaluate the effect of omega-3 fatty acids supplementation on lipid peroxidation and antioxidant enzyme levels associated with histopathologic changes induced by gamma irradiation in the testis and brain of male albino rats. Rats were whole body exposed to radiation at a single dose of 3 Gy. Omega-3 fatty acids (0.4 gm/kg b wt/day) were given to rats, by gavages, for 15 consecutive days before irradiation and for 15 days after irradiation. Rats were sacrificed one and 15 days post irradiation .Biochemical analysis of testis and cerebral cortex samples showed that irradiation induced a significant increase in xanthine oxidase (XO) activity and lipid peroxidation end product malondialdehyde (MDA) and a decrease in the content of reduced glutathione (GSH) and activity of antioxidant enzymes; glutathione peroxidase (GPX), superoxide dismutase (SOD) and catalase (CAT).Histological examination of testis and cerebral cortex tissues showed spermatogonia degeneration, apoptosis and necrosis in the testis and neurons cell bodies with ill defined and even ruptured cell membrane and damaged blood capillaries in the cerebral cortex. Omega-3 administration has attenuated the toxic effects of radiation by decreasing the levels of MDA, and XO, and increasing the activity of endogenous antioxidant enzymes, which was associated with amelioration of the histological injury markers in both testis and cerebral cortex. It could be postulated that omega-3 fatty acids as a multi-functional dietary supplement could exert a modulatory role in radiation- induced testis and cerebral cortex biochemical and histological changes through its antioxidant properties.

Treatment Outcome of Mucosa Associated Lymphoid Tissue (MALT) Marginal Zone Non-Hodgkin's Lymphoma. Single Institutional Experience

International Nuclear Information System (INIS)

Hamada, E.; Omar, H.; Abd El-Kader, Y.; Makram, O.

2003-01-01

To evaluate the treatment outcome in patients with mucosa associated lymphoid tissue (MALT) lymphoma in terms of response to treatment, progression-free and overall survivals as well as prognostic factors. Patients and Methods: Between 1995 and 2002,40 patients with clinical stages (CS) I-IV MALT lymphoma were treated at NEMROCK. The progression free survival (PFS) and overall survival (OAS) were calculated using the Kaplan Meier technique. Thirty-one patients (77.5%) had CS I-II and 9 (22.5%) had CS III-IV disease. Twenty of the 31 CS I-II patients received radiation therapy alone, five patients received chemotherapy, while three patients were treated by triple therapy (Amoxicillin, Omeperazole, Clarithromycin). Among the 9 CS III-IV patients, treatment included chemotherapy alone (6 patients), chemo radiation (2 patients) and surgery (one patient). The median followup period was 40 months. 19 out of twenty patients with CS I-II treated by radiation therapy alone had a 95% response rate (CR 85% - PR 10%). Among the study population (40 patients), the 5 year OAS and PFS were 86% and 66%, respectively. The 5 year OAS was 86% and PFS was 72% among CS III patients; the corresponding estimates in CS III-IV patients were 70% and 28%, respectively. Using multivariate analysis, there was a significant correlation between the stage of the disease, site of presentation (non GIT) and the overall survival. Modest doses of radiation therapy provide better local control in patients with early stage MALT lymphoma. The poor PFS in advanced staged disease suggests the need for further clinical trials evaluating novel drug approaches taking into consideration the biological behavior and the indolent nature of such disease entity

Skin-associated lymphoid tissues (SALT): origins and functions

International Nuclear Information System (INIS)

Streilein, J.W.

1983-01-01

The skin has an unusual set of immunologic requirements. It is confronted by a specialized set of pathogenic organisms and environmental chemicals that represent a distinctive spectrum of antigenic specificities. Skin is subjected to physicochemical stresses such as irradiation with ultraviolet light that alter dramatically its immunologic properties. It is proposed that nature has provided skin with a unique collection of lymphoid cells, reticular cells, and organized lymphoid organs to deal with these special demands. Evidence in favor of the existence of skin-associated lymphoid tissues (SALT) includes (1) the cutaneous microenvironment is capable on its own of accepting, processing, and presenting nominal antigen; (2) strategically located peripheral lymph nodes are able to accept immunogenic signals derived from skin; (3) subsets of T lymphocytes display differential affinity for skin and its associated peripheral nodes; and (4) acquisition of this affinity by T cells is determined at least in part by differentiation signals received in situ from resident cutaneous cells. Responsibility for the establishment and integration of SALT rests with keratinocytes, Langerhans cells, and immunocompetent lymphocytes, each of which contributes uniquely to the synthesis. Together they provide skin with immune surveillance that effectively prejudices against the development of cutaneous neoplasms and persistent infection with intracellular pathogens. In patients who have been under long-term immunosuppressive therapy, the large majority of nonlymphoid malignancies arise within the skin, rather than other types of tissues. These data suggest that immune surveillance, once thought to be an immune defense operative in all somatic tissues, is a specialized immune function dedicated to the skin and mediated by SALT

Study on the damage effect of 131I-iodinated oil internal radiation in SMMC-7721 hepatoma model in rat

International Nuclear Information System (INIS)

Wu Shuyan; Zhang Xuguang; Wang Xiangying; Li Su'an; Mao Dihua

2004-01-01

Objective: To investigate the damage effect of 131 I-iodinated oil internal radiation in hepatoma. Methods: SMMC-7721 rat hepatoma model was used to evaluate the damage of 131 I-iodinated oil internal radiation in carcinoma. 131 I-iodinated oil was injected sector-shapely into tumor model of SMMC-7721 hepatoma with arc-needle, matched with routine straight-needle injection. Tumor damage induced by 131 I-iodinated oil intralesion radiation in the carcinoma models are recorded through survival time, weight of rat, local carcinoma, pathology, electron microscopy. Results: Arc-needle injection 131 I-iodinated oil in SMMC-7721 hepatoma at subcutis could increase rat's survival time, the body weight kept less descent, the lumps necrosed wholly. Pathology and ultrastructure detection revealed cell necrosis and collapse, sever nuclear damage was observed in the death cells. The early characteristics of necrosis such as margination of heterochromatin was also found in some tumor cells. Besides, well differentiated tumor cells, degenerative tumor cells and some lymphocytes were seen. Conclusion: Arc-needle injection 131 I-iodinated oil step-by step sector-shapely into tumor is a better method and necrosis is the major effect of 131 I-iodinated oil internal radiation in carcinoma at the level of treated dosage

Treatment of non-vital primary molar using lesion sterilization and tissue repair (LSTR 3Mix-MP

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Tania Saskianti

2013-06-01

Full Text Available Background: Root canal preparation and anatomic variations of deciduous teeth often cause the child patient uncooperative and sometimes the treatment failure. the non-threatening treatment and non-invasive approaches is needed to obtain a good cooperation from child patient. Purpose: The study was aimed to clinically evaluate the use of 3Mix-MP- a combination of antibacterial drugs, i.e. metronidazole, minocycline and ciprofloxacin (3Mix, and macrogol and propylene glycol (MP - as pulp medicament on a necroses primary molar. Methods: Subject were the children patients of Pediatric Dental Clinic Universitas Airlangga Dental Hospital. Eight primary molars with pulp necroses due to dental caries were selected as samples. The treatment was done based on the concept of lesion sterilization and tissue repair (LSTR therapy. A slice of 3 Mix-MP pastes was placed in the cavity and then sealed with glassionomer cement. Subjects were asked for recall visit in 1, 3 and 6 months post treatment, for clinical and radiographic evaluation. The antibacterial effect of 3 Mix-MP was compared with tempophore on mixed bacteria of pulp cavity which was isolated prior to therapy. The antibacterial effect was determined by measuring the inhibition zone after 24 hours anaerobe incubation. Results: Seven out of 8 subjects on recall visit showed no acute or chronic clinical symptoms, such as fistulae, abscess, purulent exudates, swelling or feel any pain during mastication. Microbiological test result showed LSTR 3Mix-MP had antibacterial effect higher than tempophore (p<0.001. Conclusion: The study revealed that 3Mix-MP treatment showed clinical and radiographic positive response on necrose primary molar.Latar belakang: Preparasi saluran akar dan variasi anatomi gigi sulung seringkali menyebabkan pasien anak tidak kooperatif dan kadang menyebabkan kegagalan perawatan. Perawatan yang tidak menakutkan dan non-invasif diperlukan untuk mendapatkan kerjasama yang baik dari

THz near-field imaging of biological tissues employing synchrotron radiation

International Nuclear Information System (INIS)

Schade, Ulrich; Holldack, Karsten; Martin, Michael C.; Fried, Daniel

2004-01-01

Terahertz scanning near-field infrared microscopy (SNIM) below 1 THz is demonstrated. The near-field technique benefits from the broadband and highly brilliant coherent synchrotron radiation (CSR) from an electron storage ring and from a detection method based on locking onto the intrinsic time structure of the synchrotron radiation. The scanning microscope utilizes conical wave guides as near-field probes with apertures smaller than the wavelength. Different cone approaches have been investigated to obtain maximum transmittance. Together with a Martin-Puplett spectrometer the set-up enables spectroscopic mapping of the transmittance of samples well below the diffraction limit. Spatial resolution down to about lambda/40 at 2 wavenumbers (0.06 THz) is derived from the transmittance spectra of the near-field probes. The potential of the technique is exemplified by imaging biological samples. Strongly absorbing living leaves have been imaged in transmittance with a spatial resolution of 130 mu-m at about 12 wave numbers (0.36 THz). The THz near-field images reveal distinct structural differences of leaves from different plants investigated. The technique presented also allows spectral imaging of bulky organic tissues. Human teeth samples of various thicknesses have been imaged between 2 and 20 wavenumbers (between 0.06and 0.6 THz). Regions of enamel and dentin within tooth samples are spatially and spectrally resolved, and buried caries lesions are imaged through both the outer enamel and into the underlying dentin

SNPs in genes implicated in radiation response are associated with radiotoxicity and evoke roles as predictive and prognostic biomarkers

International Nuclear Information System (INIS)

Alsbeih, Ghazi; El-Sebaie, Medhat; Al-Harbi, Najla; Al-Hadyan, Khaled; Shoukri, Mohamed; Al-Rajhi, Nasser

2013-01-01

Biomarkers are needed to individualize cancer radiation treatment. Therefore, we have investigated the association between various risk factors, including single nucleotide polymorphisms (SNPs) in candidate genes and late complications to radiotherapy in our nasopharyngeal cancer patients. A cohort of 155 patients was included. Normal tissue fibrosis was scored using RTOG/EORTC grading system. A total of 45 SNPs in 11 candidate genes (ATM, XRCC1, XRCC3, XRCC4, XRCC5, PRKDC, LIG4, TP53, HDM2, CDKN1A, TGFB1) were genotyped by direct genomic DNA sequencing. Patients with severe fibrosis (cases, G3-4, n = 48) were compared to controls (G0-2, n = 107). Univariate analysis showed significant association (P < 0.05) with radiation complications for 6 SNPs (ATM G/A rs1801516, HDM2 promoter T/G rs2279744 and T/A rs1196333, XRCC1 G/A rs25487, XRCC5 T/C rs1051677 and TGFB1 C/T rs1800469). In addition, Kaplan-Meier analyses have also highlighted significant association between genotypes and length of patients’ follow-up after radiotherapy. Multivariate logistic regression has further sustained these results suggesting predictive and prognostic roles of SNPs. Univariate and multivariate analysis suggest that radiation toxicity in radiotherapy patients are associated with certain SNPs, in genes including HDM2 promoter studied for the 1st time. These results support the use of SNPs as genetic predictive markers for clinical radiosensitivity and evoke a prognostic role for length of patients’ follow-up after radiotherapy

Evaluating differential nuclear DNA yield rates and osteocyte numbers among human bone tissue types: A synchrotron radiation micro-CT approach.

Science.gov (United States)

Andronowski, Janna M; Mundorff, Amy Z; Pratt, Isaac V; Davoren, Jon M; Cooper, David M L

2017-05-01

Molecular human identification has conventionally focused on DNA sampling from dense, weight-bearing cortical bone tissue, typically from femora or tibiae. A comparison of skeletal elements from three contemporary individuals demonstrated that elements with high quantities of cancellous bone yielded nuclear DNA at the highest rates, suggesting that preferentially sampling cortical bone may be suboptimal (Mundorff & Davoren, 2014). Despite these findings, the reason for the differential DNA yields between cortical and cancellous bone tissues remains unknown. The primary goal of this work is to ascertain whether differences in bone microstructure can be used to explain differential nuclear DNA yield among bone tissue types observed by Mundorff and Davoren (2014), with a focus on osteocytes and the three-dimensional (3D) quantification of their associated lacunae. Osteocytes and other bone cells are recognized to house DNA in bone tissue, thus examining the density of their lacunae may explain why nuclear DNA yield rates differ among bone tissue types. Lacunae were visualized and quantified using synchrotron radiation-based micro-Computed Tomographic imaging (SR micro-CT). Volumes of interest (VOIs) from cortical and cancellous bone tissues (n=129) were comparatively analyzed from the three skeletons sampled for Mundorff and Davoren's (2014) study. Analyses tested the primary hypothesis that the abundance and density of osteocytes (inferred from their lacunar spaces) vary between cortical and cancellous bone tissue types. Results demonstrated that osteocyte lacunar abundance and density vary between cortical and cancellous bone tissue types, with cortical bone VOIs containing a higher lacunar abundance and density. We found that the osteocyte lacunar density values are independent of nuclear DNA yield, suggesting an alternative explanation for the higher nuclear DNA yields from bones with greater quantities of cancellous bone tissue. The use of SR micro-CT allowed for

Coral skeletons defend against ultraviolet radiation.

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Ruth Reef

Full Text Available BACKGROUND: Many coral reef organisms are photosynthetic or have evolved in tight symbiosis with photosynthetic symbionts. As such, the tissues of reef organisms are often exposed to intense solar radiation in clear tropical waters and have adapted to trap and harness photosynthetically active radiation (PAR. High levels of ultraviolet radiation (UVR associated with sunlight, however, represent a potential problem in terms of tissue damage. METHODOLOGY/PRINCIPAL FINDINGS: By measuring UVR and PAR reflectance from intact and ground bare coral skeletons we show that the property of calcium carbonate skeletons to absorb downwelling UVR to a significant extent, while reflecting PAR back to the overlying tissue, has biological advantages. We placed cnidarians on top of bare skeletons and a UVR reflective substrate and showed that under ambient UVR levels, UVR transmitted through the tissues of cnidarians placed on top of bare skeletons were four times lower compared to their counterparts placed on a UVR reflective white substrate. In accordance with the lower levels of UVR measured in cnidarians on top of coral skeletons, a similar drop in UVR damage to their DNA was detected. The skeletons emitted absorbed UVR as yellow fluorescence, which allows for safe dissipation of the otherwise harmful radiation. CONCLUSIONS/SIGNIFICANCE: Our study presents a novel defensive role for coral skeletons and reveals that the strong UVR absorbance by the skeleton can contribute to the ability of corals, and potentially other calcifiers, to thrive under UVR levels that are detrimental to most marine life.

Risks associated with radiation: General information

International Nuclear Information System (INIS)

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

1995-07-01

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

Risks associated with radiation: General information

Energy Technology Data Exchange (ETDEWEB)

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

1995-07-01

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

Genetic polymorphisms and tissue expression of interleukin-22 associated with risk and therapeutic response of gastric mucosa-associated lymphoid tissue lymphoma

International Nuclear Information System (INIS)

Liao, F; Hsu, Y-C; Kuo, S-H; Yang, Y-C; Chen, J-P; Hsu, P-N; Lin, C-W; Chen, L-T; Cheng, A-L; Fann, C S J; Lin, J-T; Wu, M-S

2014-01-01

Chronic Helicobacter pylori-stimulated immune reactions determine the pathogenesis of gastric mucosa-associated lymphoid tissue (MALT) lymphoma. We aimed to explore the genetic predisposition to this lymphoma and its clinical implication. A total of 68 patients and 140 unrelated controls were genotyped for 84 single-nucleotide polymorphisms in genes encoding cytokines, chemokines and related receptors that play important roles in T cell-mediated gastrointestinal immunity. Five genotypes in IL-22, namely CC at rs1179246, CC at rs2227485, AA at rs4913428, AA at rs1026788 and TT at rs7314777, were associated with disease susceptibility. The former four genotypes resided in the same linkage disequilibrium block (r 2 =0.99) that conferred an approximately threefold higher risk. In vitro experiments demonstrated that co-culturing peripheral mononuclear cells or CD4 + T cells with H. pylori stimulated the secretion of interleukin-22 (IL-22), and that IL-22 induced the expression of antimicrobial proteins, RegIIIα and lipocalin-2, in gastric epithelial cells. Furthermore, patients with gastric tissue expressing IL-22 were more likely to respond to H. pylori eradication (14/22 vs 4/19, P<0.006). We conclude that susceptibility of gastric MALT lymphoma is influenced by genetic polymorphisms in IL-22, the product of which is involved in mucosal immunity against H. pylori and associated with tumor response to H. pylori eradication