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Sample records for beam radiation-induced xerostomia

  1. A survey of techniques to reduce and manage external beam radiation-induced xerostomia in British oncology and radiotherapy departments

    Energy Technology Data Exchange (ETDEWEB)

    Macknelly, Andrew [Norfolk and Norwich University Hospital (United Kingdom); Day, Jane [Faculty of Health, Wellbeing and Science, University Campus Suffolk, Waterfront Building, Neptune Quay, Ipswich (United Kingdom)], E-mail: j.day@ucs.ac.uk

    2009-11-15

    Xerostomia is the most common side effect of external beam radiotherapy to the head and neck [Anand A, Jain J, Negi P, Chaudhoory A, Sinha S, Choudhury P, et-al. Can dose reduction to one parotid gland prevent xerostomia? - A feasibility study for locally advanced head and neck cancer patients treated with intensity-modulated radiotherapy. Clinical Oncology 2006;18(6):497-504.]. A survey was carried out in British oncology departments to determine what treatment regimes, to minimise xerostomia, are used for patients with head-and-neck cancers treated with external beam radiotherapy. A semi-structured questionnaire consisting of both quantitative and qualitative questions was designed that asked departments which of the identified methods they used, why a method might not be currently employed, and whether its use had ever been considered. The study found that there are wide disparities between the techniques employed by oncology departments to avoid and reduce xerostomia in patients with cancers of the head and neck. The National Institute of Clinical Health and Excellence, [National Institute for Clinical Health and Excellence (NICE). Improving outcomes in head and neck cancers: the manual. London: Office of Public Sector Information; 2004.] for example, recommends that patients are given dental care and dietary advice but some departments did not appear to be doing this. Less than half of departments stated that they offer complementary therapies and less than 40% prescribed pilocarpine, a saliva-stimulant. Only two respondents stated that they use amifostine, a radioprotector, during radiotherapy treatment to the head and neck. The results also suggested a move toward using Intensity Modulated Radiotherapy (IMRT) for treating head-and-neck cancers which offers better normal tissue sparing than three-dimensional conformal radiotherapy. [Anand A, Jain J, Negi P, Chaudhoory A, Sinha S, Choudhury P, et al. Can dose reduction to one parotid gland prevent xerostomia

  2. A survey of techniques to reduce and manage external beam radiation-induced xerostomia in British oncology and radiotherapy departments

    International Nuclear Information System (INIS)

    Xerostomia is the most common side effect of external beam radiotherapy to the head and neck [Anand A, Jain J, Negi P, Chaudhoory A, Sinha S, Choudhury P, et-al. Can dose reduction to one parotid gland prevent xerostomia? - A feasibility study for locally advanced head and neck cancer patients treated with intensity-modulated radiotherapy. Clinical Oncology 2006;18(6):497-504.]. A survey was carried out in British oncology departments to determine what treatment regimes, to minimise xerostomia, are used for patients with head-and-neck cancers treated with external beam radiotherapy. A semi-structured questionnaire consisting of both quantitative and qualitative questions was designed that asked departments which of the identified methods they used, why a method might not be currently employed, and whether its use had ever been considered. The study found that there are wide disparities between the techniques employed by oncology departments to avoid and reduce xerostomia in patients with cancers of the head and neck. The National Institute of Clinical Health and Excellence, [National Institute for Clinical Health and Excellence (NICE). Improving outcomes in head and neck cancers: the manual. London: Office of Public Sector Information; 2004.] for example, recommends that patients are given dental care and dietary advice but some departments did not appear to be doing this. Less than half of departments stated that they offer complementary therapies and less than 40% prescribed pilocarpine, a saliva-stimulant. Only two respondents stated that they use amifostine, a radioprotector, during radiotherapy treatment to the head and neck. The results also suggested a move toward using Intensity Modulated Radiotherapy (IMRT) for treating head-and-neck cancers which offers better normal tissue sparing than three-dimensional conformal radiotherapy. [Anand A, Jain J, Negi P, Chaudhoory A, Sinha S, Choudhury P, et al. Can dose reduction to one parotid gland prevent xerostomia

  3. [Radiation-induced xerostomia: prevention, treatment, perspectives].

    Science.gov (United States)

    Guinand, N; Dulguerov, P; Giger, R

    2007-10-01

    Most of head and neck cancer patients will undergo radiotherapy. Xerostomia is probably its most frequent side effect. Subjective and objective criteria allow evaluating and grading xerostomia. New radiotherapy techniques and use of cytoprotectants can help to preserve salivary gland function. Parasym-pathicomimetics and saliva substitutes reduce symptoms. Strict mouth cleaning and fluoride's use prevent teeth deterioration and infections. Important breakthroughs have been made in the pathophysiology of xerostomia and new treatments are developed. PMID:17970157

  4. Submandibular salivary gland transfer prevents radiation-induced xerostomia

    International Nuclear Information System (INIS)

    Background: Xerostomia is a significant morbidity of radiation therapy in the management of head and neck cancers. We hypothesized that the surgical transfer of one submandibular salivary gland to submental space, outside the proposed radiation field, prior to starting radiation treatment, would prevent xerostomia. Methods: We are conducting a prospective clinical trial where the submandibular gland is transferred as part of the surgical intervention. The patients are followed clinically, with salivary flow studies and University of Washington quality of life questionnaire. Results: We report early results of 16 patients who have undergone this procedure. Seven patients have finished and 2 patients are currently undergoing radiation treatment. In 2 patients, no postoperative radiation treatment was indicated. Two patients are waiting to start radiation treatment and 2 patients refused treatment after surgery. The surgical transfer was abandoned in 1 patient. All of the transferred salivary glands were positioned outside the proposed radiation fields and were functional. The patients did not complain of any xerostomia and developed only minimal oral mucositis. There were no surgical complications. Conclusions: Surgical transfer of a submandibular salivary gland to the submental space (outside the radiation field) preserves its function and prevents the development of radiation-induced xerostomia

  5. Acupuncture treatment of patients with radiation-induced xerostomia

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    Blom, M.; Dawidson, I.; Johnson, G.; Angmar-Maansson, B. [Karolinska Inst., Huddinge (Sweden). Dept. of Cardiology; Fernberg, J.-O. [Karolinska Hospital, Stockholm (Sweden). Dept. of General Oncology

    1996-05-01

    Xerostomia is a common and usually irreversible side effect in patients receiving radiation therapy (>50 Gy) for head and neck cancer. Of 38 patients with radiation-induced xerostomia, 20 in the experimental group were treated with classical acupuncture and 18 patients in the control group received superficial acupuncture as placebo. Within both groups the patients showed significantly increased salivary flow rates after the acupuncture treatment. In the experimental group 68% and in the control group 50% of the patients had increased salivary flow rates at the end of the observation period. Among those patients who had had all their salivary glands irradiated, 50% in both groups showed increased salivary flow rates (>20%) by the end of the observation period of 1 year. The study indicates that among the patients who had increased salivary flow rates already after the first 12 acupuncture sessions, the majority had high probability of continual improvement after the completion of acupuncture treatment. (Author).

  6. Acupuncture treatment of patients with radiation-induced xerostomia

    International Nuclear Information System (INIS)

    Xerostomia is a common and usually irreversible side effect in patients receiving radiation therapy (>50 Gy) for head and neck cancer. Of 38 patients with radiation-induced xerostomia, 20 in the experimental group were treated with classical acupuncture and 18 patients in the control group received superficial acupuncture as placebo. Within both groups the patients showed significantly increased salivary flow rates after the acupuncture treatment. In the experimental group 68% and in the control group 50% of the patients had increased salivary flow rates at the end of the observation period. Among those patients who had had all their salivary glands irradiated, 50% in both groups showed increased salivary flow rates (>20%) by the end of the observation period of 1 year. The study indicates that among the patients who had increased salivary flow rates already after the first 12 acupuncture sessions, the majority had high probability of continual improvement after the completion of acupuncture treatment. (Author)

  7. Pilocarpine and carbacholine in treatment of radiation-induced xerostomia

    International Nuclear Information System (INIS)

    Twenty-four patients with radiation-related xerostomia were treated with oral pilocarpine solution 6 mg t.i.d., and after a 4-week drug-free period 16 of these patients were treated with carbacholine 2 mg tablets t.i.d. Basal and stimulated whole saliva flow rates were measured before commencing the drug treatment, and after 1 and 12 weeks on treatment. On a subjective linear scale both pilocarpine (p=0.01) and carbacholine (p=0.02) improved mouth moistness. Only 2 of the 8 patients with no basal or stimulated saliva flow reported some subjective benefit from the drug treatment, whereas all 8 patients with less severe xerostomia improved (p=0.007). However, the salivary flow rates measured 12 h after the last drug dose did not improve with either drug. Both drugs were generally well tolerated. It is concluded that both drugs may be useful in the treatment of radiation-induced xerostomia among patients with residual salivary function. (author). 6 refs., tabs

  8. Prevention of radiation induced xerostomia and improved quality of life: Submandibular salivary gland transfer

    International Nuclear Information System (INIS)

    Over 60,000 new cases of head and neck cancers, and approximately 15,000 deaths occur every year in the United States (1). Head and neck cancers affect more men then women by a factor of 2:1, although the incidence of women is increasing as a result of increased tobacco use (2). Over 90% of all head and neck cancers are squamous cell carcinomas; most of the remaining cancers are adenocarcinomas. A combination of radiation therapy and surgery is used as the standard, primary treatment modality. Xerostomia occurs when the salivary glands are affected by irradiation. Patients experiencing xerostomia are at an increased risk for a wide variety of oral problems; all adversely affecting one's quality of life. Currently patients make lifestyle changes, dietary modifications, and use artificial salivas, sprays, gels, and lozenges to help mask their xerostomia. However, none of these products stimulate natural salivary production and act as a replacement therapy rather then a cure for xerostomia. A new protocol, RTOG 1083 has been approved by the Radiation Therapy Oncology Group, which involves a surgical transfer of a submandibular salivary gland to the submental space (where it can be easily shielded) as a method of prevention of radiation induced xerostomia. (author)

  9. Prevention of radiation induced xerostomia by surgical transfer of submandibular salivary gland into the submental space

    International Nuclear Information System (INIS)

    Background and purpose: Xerostomia is a significant morbidity of radiation treatment in the management of head and neck cancers. We hypothesized that the surgical transfer of one submandibular salivary gland to the submental space, where it can be shielded from radiation treatment (XRT), would prevent xerostomia. Materials and methods: We conducted a prospective Phase II clinical trial and the patients were followed clinically with salivary flow studies and the University of Washington Quality of Life questionnaire. Results: We report the results on 76 evaluable patients. The salivary gland transfer was done in 60 patients. Nine patients (of 60) did not have postoperative XRT and in eight patients (of 60) the transferred gland was not shielded from XRT due to proximity of disease. The median follow up is 14 months. Of the 43 patients with the salivary gland transfer and post-operative XRT with protection of the transferred gland, 81% have none or minimal xerostomia, and 19% developed moderate to severe xerostomia. Three patients (6.9%) developed local recurrence, five patients (11.6%) developed distant metastases and five patients (11.6%) have died. There were no complications attributed to the surgical procedure. Conclusion: Surgical transfer of a submandibular salivary gland to the submental space preserves its function and prevents the development of radiation induced xerostomia

  10. Acupuncture for the prevention of radiation-induced xerostomia in patients with head and neck cancer

    Directory of Open Access Journals (Sweden)

    Fabio do Prado Florence Braga

    2011-04-01

    Full Text Available The aim of this study was to evaluate the effectiveness of acupuncture in minimizing the severity of radiation-induced xerostomia in patients with head and neck cancer. A total of 24 consecutive patients receiving > 5000 cGy radiotherapy (RT involving the major salivary glands bilaterally were assigned to either the preventive acupuncture group (PA, n = 12, treated with acupuncture before and during RT, or the control group (CT, n = 12, treated with RT and not receiving acupuncture. After RT completion, clinical response was assessed in all patients by syalometry, measuring the resting (RSFR and stimulated (SSFR salivary flow rates, and by the visual analogue scale (VAS regarding dry mouth-related symptoms. Statistical analyses were performed with repeated-measures using a mixed-effect modeling procedure and analysis of variance. An alpha level of 0.05 was accepted for statistical significance. Although all patients exhibited some degree of impairment in salivary gland functioning after RT, significant differences were found between the groups. Patients in the PA group showed improved salivary flow rates (RSFR, SSFR; p < 0.001 and decreased xerostomia-related symptoms (VAS, p < 0.05 compared with patients in the CT group. Although PA treatment did not prevent the oral sequelae of RT completely, it significantly minimized the severity of radiation-induced xerostomia. The results suggest that acupuncture focused in a preventive approach can be a useful therapy in the management of patients with head and neck cancer undergoing RT.

  11. Impact of Radiation-Induced Xerostomia on Quality of Life After Primary Radiotherapy Among Patients With Head and Neck Cancer

    International Nuclear Information System (INIS)

    Purpose: To investigate the impact of xerostomia on overall quality of life (QoL) outcome and related dimensions among head and neck cancer patients treated with primary radiotherapy. Methods and Materials: A total of 288 patients with Stage I-IV disease without distant metastases were included. Late xerostomia according to the Radiation Therapy Oncology Group (RTOG-xerostomia) and QoL (European Organization for Research and Treatment of Cancer QLC-C30) were assessed at baseline and every 6th month from 6 months to 24 months after radiotherapy. Results: A significant association was found between RTOG-xerostomia and overall QoL outcome (effect size [ES] 0.07, p 65 years). An analysis of the impact of RTOG-xerostomia on overall QoL outcome over time showed an increase from 0.09 at 6 months to 0.22 at 24 months. With elapsing time, a worsening was found for these individual scales with increasing RTOG-xerostomia. Conclusions: The results of this prospective study are the first to show a significant impact of radiation-induced xerostomia on QoL. Although the incidence of Grade ≥2 RTOG-xerostomia decreases with time, its impact on QoL increases. This finding emphasizes the importance of prevention of xerostomia

  12. 3D MR Sialography as a Tool to Investigate Radiation-Induced Xerostomia: Feasibility Study

    International Nuclear Information System (INIS)

    Purpose: To evaluate whether magnetic-resonance (MR) sialography can be used to investigate radiation-induced xerostomia. Preradiotherapy (pre-RT) and postradiotherapy (post-RT) MR sialographic images of the major salivary ducts (parotid and submandibular) were compared. Methods and Materials: Magnetic-resonance sialography was performed pre-RT, and 6 weeks and 6 months post-RT on 9 patients with T1-4N0-2M0 naso- or oropharyngeal tumors, on a 1.5-T MR scanner. Patients were positioned in the scanner, using a radiotherapy immobilization mask. Image registration of the MR sialograms pre- and post-RT with each other and with the CT and consequently the dose distribution was performed. A categorical scoring system was used to compare the visibility of ducts pre-RT and post-RT. Results: Good-quality MR sialographic images were obtained, and image registration was successful in all cases. The visibility score of the parotid ducts and submandibular ducts was reduced at 6 weeks post-RT, which means that the full trajectory of the salivary ducts, from the intraglandular space to the mouth cavity, was only partially visualized. For some of the parotid ducts, the visibility score improved at 6 months post-RT, but not for the submandibular ducts. The mean dose for the parotid glands was 35 Gy (1 standard deviation [SD] 3 Gy), and for the submandibular glands it was 62 Gy (SD, 8 Gy). Conclusion: Three-dimensional MR sialography is a promising approach for investigating xerostomia, because radiation-induced changes to the saliva content of the ducts can be visualized

  13. A Randomized, Double-Blind, Trial Of Pilocarpine With Head And Neck Irradiation For Prevention Of Radiation-Induced Xerostomia

    OpenAIRE

    Hadad P; Karimi M

    2002-01-01

    Xerostomia is one of the disturbing side-effects of the radiotherapy to the head and neck region. Pilocarpine has been approved for the treatment;of this condition in the chronic phase, but its use concurrent with radiation could also be beneficial for prevention or reducing the subsequent radiation-induced xerostomia. We undertook to test this hypothesis in a clinical trial."nMaterials and Methods: All 18- to 70-year old patients who were to be irradiated to the head and neck, with both...

  14. Effect of cepharanthin to prevent radiation induced xerostomia in head and neck cancer

    International Nuclear Information System (INIS)

    We retrospectively examined the effect of Cepharanthin to prevent radiation xerostomia in 37 cases of head and neck cancer. In the Cepharanthin group, the degree of xerostomia was milder than in the non-Cepharanthin group in spite of higher normal tissue complication probability (NTCP) and mean dose (MD) of parotid glands. In the non-Cepharanthin group, the degree of xerostomia was significantly correlated with NTCP and MD of parotid glands. MD of parotid glands and use of Cepharanthin were significantly related to more severe xerostomia by multivariate analysis with logistic regression. Cepharanthin may prevent radiation xerostomia after radiotherapy for head and neck cancer. (author)

  15. Autotransplantation of cryopreserved minor salivary glands: a new approach for management of radiation-induced xerostomia.

    Science.gov (United States)

    Kolahi, Jafar; Mansourian, Marjan

    2010-01-01

    To date, it still is impossible to successfully prevent radiation-induced xerostomia. Therefore, further research, particularly regarding treatment, is urgently warranted. Lower labial mucosa with its submucosal minor salivary glands (MSGs) of approximately 2.5 x 3 cm can be prepared by means of a surgical knife or Ellman Surgitron high-frequency/low-temperature radiosurgical device. Also we can consider area of the palatine fovea to find and remove MSGs. We can find locations containing more MSGs via scintigraphy techniques and positron emission tomography. Removing of MSGs can be done 1-2 weeks before start of radiotherapy. Subsequently the MSGs containing complex graft should be cryopreserved via liquid nitrogen for long-term storage. Autotransplantation surgery will be carried out 2-3 months after radiotherapy. The frozen tissue could be thawed rapidly in a 37 degrees C water bath for 2-3 min. Host site should be as far as possible to the radiation zone and has a good blood supply. Hyperbaric oxygen therapy (30 treatment sessions before and 10 sessions after re-implantation) is strongly recommended. An aggressive short or medium-term antibiotic treatment will necessary to avoid infection. Immunosuppressive treatment will not require. The main criticism with this hypothesis is viability and usefulness of MSGs containing graft, after being frozen and subsequently thawed. PMID:19729251

  16. Recovery time from radiation-induced xerostomia and impairment of salivary secretion

    International Nuclear Information System (INIS)

    Between June 1995 and August 1997, we treated 23 patients with head and neck malignancies using an x-ray beam and then interviewed the patients to determine the degree of subjective salivary secretion and xerostomia after long-term radiation therapy. Interviews were continued for a maximum 179 weeks (mean, 76.3 weeks) after irradiation. We scored the results as the degree of subjective salivary secretion, then noted the recovery time for salivary secretion and xerostomia. When salivary glands had been irradiated to a total dose of 30 to 60 Gy, salivary secretion and oral dryness recovered within three years in 72% (13/18) and 67% (13/18) of the patients, respectively. However, these symptoms never recovered to their original levels when the total dose was more than 60 Gy. The acute and late effects of radiation therapy may induce a risk of dental caries, oral dryness, and osteoradionecrosis as well as taste impairment. Therefore, education as to dental and oral care is mandatory for patients who will be or who have been treated with radiotherapy. (author)

  17. Recovery time from radiation-induced xerostomia and impairment of salivary secretion

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    Fukutomi, Yukimi; Kawakami, Toshiaki [Ehime Univ., Matsuyama (Japan). Hospital; Murase, Kenya; Fujii, Takashi; Ikezoe, Junpei

    2000-10-01

    Between June 1995 and August 1997, we treated 23 patients with head and neck malignancies using an x-ray beam and then interviewed the patients to determine the degree of subjective salivary secretion and xerostomia after long-term radiation therapy. Interviews were continued for a maximum 179 weeks (mean, 76.3 weeks) after irradiation. We scored the results as the degree of subjective salivary secretion, then noted the recovery time for salivary secretion and xerostomia. When salivary glands had been irradiated to a total dose of 30 to 60 Gy, salivary secretion and oral dryness recovered within three years in 72% (13/18) and 67% (13/18) of the patients, respectively. However, these symptoms never recovered to their original levels when the total dose was more than 60 Gy. The acute and late effects of radiation therapy may induce a risk of dental caries, oral dryness, and osteoradionecrosis as well as taste impairment. Therefore, education as to dental and oral care is mandatory for patients who will be or who have been treated with radiotherapy. (author)

  18. The role of stem cells in the prevention and treatment of radiation-induced xerostomia in patients with head and neck cancer.

    Science.gov (United States)

    Nevens, Daan; Nuyts, Sandra

    2016-06-01

    Xerostomia is an important complication following radiotherapy (RT) for head and neck cancer. Current treatment approaches are insufficient and can only temporarily relieve symptoms. New insights into the physiopathology of radiation-induced xerostomia might help us in this regard. This review discusses the current knowledge of salivary gland stem cells in radiation-induced xerostomia and their value in the prevention and treatment of this complication. Salivary gland stem cell transplantation, bone marrow-derived cell mobilization, molecular regulation of parotid stem cells, stem cell sparing RT, and adaptive RT are promising techniques that are discussed in this study. PMID:26880659

  19. Reduction of radiation-induced xerostomia in nasopharyngeal carcinoma using CT simulation with laser patient marking and three-field irradiation technique

    International Nuclear Information System (INIS)

    Purpose: Tumor control and reduction of postirradiation xerostomia in patients with nasopharyngeal carcinoma (NPC) using the three-field irradiation technique based on the CT-based simulation with laser patient marking was investigated. Methods and Materials: Seventy-eight patients with NPC were consecutively treated between 1983 and 1993. In 33 patients treated before 1987, target volume was determined using a conventional x-ray simulator with a reference of CT images, and the primary site was treated by the conventional parallel-opposed two-field technique (Group I). In 45 patients treated from 1987, target volume was determined using a CT simulator slice by slice, the treatment field was projected onto the patient's skin by a laser beam projector mounted on a C-arm, and the primary site was irradiated by a three-fields (anterior and bilateral) technique (Group II). In Group II, the shape of each field was determined using a beam's eye view to reduce the dose to the bilateral parotid glands. The three-field technique reduced the dose to the superficial lobe of parotid gland to about two-thirds of the dose given by the two-field technique. Radiation-induced xerostomia was evaluated by clinical symptoms and radio-isotope sialography. Results: The 5-year survival rate and disease-free survival rate were 46.6 and 31.2% in Group I, and 46.8 and 46.5% in Group II. A large variation in the volume of parotid glands were demonstrated, ranging from 9 cm3 to 61 cm3 among patients treated with CT simulation. Forty percent of the patients in Group II showed no or mild xerostomia, whereas all of the patients in Group I showed moderate to severe xerostomia (p < 0.01). The radioisotope sialography study showed that the mean secretion ratio by acid stimulation was improved from 3.8% in the Group I to 15.2% in the Group II (p < 0.01). Conclusions: CT simulation was useful to determine the size and shape of each field to reduce the dose to the parotid gland, of which size varies

  20. The role of Magnetic resonance sialography in evaluating radiation-induced xerostomia for patients with early stage nasopharyngeal carcinoma

    International Nuclear Information System (INIS)

    Objective: To investigate the value of magnetic resonance sialography (MRS) as a noninvasive tool in evaluating major salivary gland function before and after radiotherapy (RT) for nasopharyngeal carcinoma patients. Methods: From August 2009 to June 2010, patients with stage I and IIa (AJCC/UICC 2002) nasopharyngeal carcinoma were enrolled. All the patients were treated with intensity modulated radiation therapy alone. MRS with salivary stimulation was performed in patients before and after RT on a 3.0T MR scanner. An MRS categorical scoring system was used to compare the visibility of ducts pre-RT and post-RT. The relationship between MRS score and EORTC Core QOL and EORTC Head and Neck QOL was analyzed. Spearman rank correlation test was performed to analyze the non-stimulated and stimulated MRS findings and the clinical severity of xerostomia. Results: All 10 enrolled patients completed planned treatment.The mean dose of the parotid glands and submandibular glands were (37.99 ± 3.70) Gy and (55.65 ± 2.99) Gy, respectively. Good-quality MRS images were obtained. The visibility scores of both the parotid and submandibular ducts were increased after secretion stimulation. Irradiation decreased the visualization of the salivary ducts and attenuated the response to secretion stimulation. There were specific correlations between post-RT secretion response of the parotid gland and EORTC QLQ scales (global QOL scale in QLQ-C30 (rs =0.636, P =0.048) and xerostomia scale in QLQ H and N35 (rs =- 0.694, P =0.026)). Conclusions: MRS can be used as a non-invasive way to evaluated of the functional changes of major salivary glands before and after RT and as a promising approach for investigating radiation-induced xerostomia. (authors)

  1. Quantitative assessment of salivary gland function by radioisotopic scanning in a randomized trial of pilocarpine for prevention of radiation Induced Xerostomia

    International Nuclear Information System (INIS)

    Radioisotope scanning is the best method for objective assessment of salivary gland function. Thus, it was used in a randomized trial of concomitant pilocarpine for assessment of radiation-induced xerostomia, in addition to subjective evaluation by an approved questionnaire and objective standard xerostomia grading. Patients randomized in a placebo-controlled trial of pilocarpine concurrent with irradiation for prevention of radiation-induced xerostomia were evaluated by salivary gland scintigraphy immediately before and 6 months after the end of head and neck radiotherapy. Salivary gland function was measured by ejection fraction (E F) of Technetium-99 m pertechnetate. The mean values for pre-and post-radiotherapy scans were calculated and compared. Also post-radiotherapy scan findings in the two groups of pilocarpine and placebo were compared using the Student's t-test. In addition, comparison was made between the scan results and the subjective findings and objective grading s.Twenty patients underwent the pre-radiotherapy salivary scintigraphy, and also 20 post-radiotherapy scans were performed . Mean parotid E F was 60.85% in the pre-radiotherapy and 9.08% in the post-radiotherapy scans (p<0.01). The means for submandibular glands in the pre-and post-radiotherapy scans were 41% and 11.2%, respectively (p<0.01). Also the mean E F was 14.5% in the pilocarpine group and 3.65 in the placebo group for parotid glands (p=0.07) and 18.3% and 4.1% respectively for submandibular glands (p<0.05). The salivary scans confirmed the subjective and objective xerostomia findings. Salivary gland scintigraphy is a valuable method for evaluation of xerostomia after head and neck radiotherapy, quantitatively demonstrating the protective effect of pilocarpine compared to placebo on salivary glands

  2. Acupuncture-Like Transcutaneous Electrical Nerve Stimulation Versus Pilocarpine in Treating Radiation-Induced Xerostomia: Results of RTOG 0537 Phase 3 Study

    International Nuclear Information System (INIS)

    Purpose and Objectives: This report presents the analysis of the RTOG 0537 multicenter randomized study that compared acupuncture-like transcutaneous stimulation (ALTENS) with pilocarpine (PC) for relieving radiation-induced xerostomia. Methods and Materials: Eligible patients were randomized to twice-weekly 20-minute ALTENS sessions for 24 sessions during 12 weeks or PC (5 mg 3 times daily for 12 weeks). The primary endpoint was the change in the University of Michigan Xerostomia-Related Quality of Life Scale (XeQOLS) scores from baseline to 9 months from randomization (MFR). Secondary endpoints included basal and citric acid primed whole salivary production (WSP), ratios of positive responders (defined as patients with ≥20% reduction in overall radiation-induced xerostomia symptom burden), and the presence of adverse events based on the Common Terminology Criteria for Adverse Events version 3. An intention-to-treat analysis was conducted. Results: One hundred forty-eight patients were randomized. Only 96 patients completed the required XeQOLS and were evaluable at 9 MFR (representing merely 68.6% statistical power). Seventy-six patients were evaluable at 15 MFR. The median change in the overall XeQOLS in ALTENS and PC groups at 9 and 15 MFR were −0.53 and −0.27 (P=.45) and −0.6 and −0.47 (P=.21). The corresponding percentages of positive responders were 81% and 72% (P=.34) and 83% and 63% (P=.04). Changes in WSP were not significantly different between the groups. Grade 3 or less adverse events, mostly consisting of grade 1, developed in 20.8% of patients in the ALTENS group and in 61.6% of the PC group. Conclusions: The observed effect size was smaller than hypothesized, and statistical power was limited because only 96 of the recruited 148 patients were evaluable. The primary endpoint—the change in radiation-induced xerostomia symptom burden at 9 MFR—was not significantly different between the ALTENS and PC groups. There was significantly less

  3. Acupuncture-Like Transcutaneous Electrical Nerve Stimulation Versus Pilocarpine in Treating Radiation-Induced Xerostomia: Results of RTOG 0537 Phase 3 Study

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    Wong, Raimond K.W., E-mail: wongrai@hhsc.ca [McMaster University, Juravinski Cancer Centre, Hamilton, Ontario (Canada); Deshmukh, Snehal [NRG Oncology Statistics and Data Management Center, Philadelphia, Pennsylvania (United States); Wyatt, Gwen [Michigan State University, East Lansing, Michigan (United States); Sagar, Stephen [McMaster University, Juravinski Cancer Centre, Hamilton, Ontario (Canada); Singh, Anurag K. [Roswell Park Cancer Institute, Buffalo, New York (United States); Sultanem, Khalil [McGill University, Montreal, Quebec (Canada); Nguyen-Tân, Phuc F. [Centre Hospitalier de l' Université de Montréal-Hôpital Notre-Dame, Montreal, Quebec (Canada); Yom, Sue S. [University of California San Francisco, San Francisco, California (United States); Cardinale, Joseph [Yale-New Haven Hospital Saint Raphael Campus, New Haven, Connecticut (United States); Yao, Min [University Hospitals of Cleveland, Cleveland, Ohio (United States); Hodson, Ian [McMaster University, Juravinski Cancer Centre, Hamilton, Ontario (Canada); Matthiesen, Chance L. [University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma (United States); Suh, John [Cleveland Clinic Foundation, Cleveland, Ohio (United States); Thakrar, Harish [John H. Stroger, Jr. Hospital of Cook County MB-CCOP, Chicago, Illinois (United States); Pugh, Stephanie L. [NRG Oncology Statistics and Data Management Center, Philadelphia, Pennsylvania (United States); Berk, Lawrence [University of South Florida H. Lee Moffitt Cancer Center, Tampa, Florida (United States)

    2015-06-01

    Purpose and Objectives: This report presents the analysis of the RTOG 0537 multicenter randomized study that compared acupuncture-like transcutaneous stimulation (ALTENS) with pilocarpine (PC) for relieving radiation-induced xerostomia. Methods and Materials: Eligible patients were randomized to twice-weekly 20-minute ALTENS sessions for 24 sessions during 12 weeks or PC (5 mg 3 times daily for 12 weeks). The primary endpoint was the change in the University of Michigan Xerostomia-Related Quality of Life Scale (XeQOLS) scores from baseline to 9 months from randomization (MFR). Secondary endpoints included basal and citric acid primed whole salivary production (WSP), ratios of positive responders (defined as patients with ≥20% reduction in overall radiation-induced xerostomia symptom burden), and the presence of adverse events based on the Common Terminology Criteria for Adverse Events version 3. An intention-to-treat analysis was conducted. Results: One hundred forty-eight patients were randomized. Only 96 patients completed the required XeQOLS and were evaluable at 9 MFR (representing merely 68.6% statistical power). Seventy-six patients were evaluable at 15 MFR. The median change in the overall XeQOLS in ALTENS and PC groups at 9 and 15 MFR were −0.53 and −0.27 (P=.45) and −0.6 and −0.47 (P=.21). The corresponding percentages of positive responders were 81% and 72% (P=.34) and 83% and 63% (P=.04). Changes in WSP were not significantly different between the groups. Grade 3 or less adverse events, mostly consisting of grade 1, developed in 20.8% of patients in the ALTENS group and in 61.6% of the PC group. Conclusions: The observed effect size was smaller than hypothesized, and statistical power was limited because only 96 of the recruited 148 patients were evaluable. The primary endpoint—the change in radiation-induced xerostomia symptom burden at 9 MFR—was not significantly different between the ALTENS and PC groups. There was significantly less

  4. Evaluation of effect of transcutaneous electrical nerve stimulation on salivary flow rate in radiation induced xerostomia patients: A pilot study

    Directory of Open Access Journals (Sweden)

    Anusha Rangare Lakshman

    2015-01-01

    Conclusion: The present study gave us an insight about the effectiveness of TENS therapy in stimulating salivary flow in healthy subjects and it is very effective when used in conjunction with radiation therapy by reducing the side-effects of radiation therapy. Hence, TENS therapy can be used as an adjunctive method for the treatment of xerostomia along with other treatment modalities.

  5. Oral pilocarpine for radiation-induced xerostomia: integrated efficacy and safety results from two prospective randomized clinical trials

    International Nuclear Information System (INIS)

    Purpose: Pilocarpine hydrochloride administered in either a fixed-dose or in a dose-titration protocol three times a day for 12 weeks was evaluated for its ability to relieve symptoms of postradiation xerostomia and to improve saliva production. The studies were randomized, double-blind, placebo-controlled, multicenter clinical trials. A total of 369 patients who had received at least 40 Gy of radiation to the head and neck with clinically significant xerostomia were enrolled in the two studies. In the dose-titration study, 162 patients were enrolled and they received a thrice daily regimen of 2.5 mg tablets for first 4 weeks, 5.0 mg tablets for the second 4 weeks, and 10.0 mg tablets for last 4 weeks of a 12-week study. Patients in the titration study were allowed to down titrate following at least one dose escalation to alleviate bothersome side effects, if any. In the fixed dose study, 207 patients received either placebo, 5.0 mg, or 10.0 mg tablets t.i.d. for 12 weeks. Methods and Materials: Patients were evaluated for symptomatic relief by responding to questionnaires using visual analog scales and categorical questions; and, for saliva production by sialometry. Questionnaires measured relief of intraoral dryness, improvement in overall condition (global response), oral discomfort, difficulty in speaking, chewing and swallowing, denture wearing, and usage of artificial saliva. Evaluations were conducted at baseline, and weeks 4, 8, and 12. Results: There were statistically significant improvements in salivary flow in pilocarpine treatment groups vs. placebo. There was a significant improvement in the overall 'global' condition of xerostomia associated with the use of pilocarpine in both studies. In the fixed-dose study, there were significant improvements in oral dryness, mouth comfort, ability to speak, and reduction in the use of oral comfort agents. The dose-titration study showed improvements in dryness that approached significance (p = 0.057) and a

  6. A Phase II Study of Submandibular Gland Transfer Prior to Radiation for Prevention of Radiation-induced Xerostomia in Head-and-Neck Cancer (RTOG 0244)

    Energy Technology Data Exchange (ETDEWEB)

    Jha, Naresh, E-mail: naresh.jha@albertahealthservices.ca [University of Alberta, Cross Cancer Institute, Edmonton, Alberta (Canada); Harris, Jonathan [Radiation Therapy Oncology Group Statistical Center, Philadelphia, Pennsylvania (United States); Seikaly, Hadi [University of Alberta, Edmonton, Alberta (Canada); Jacobs, John R. [Wayne State University School of Medicine, Detroit, Michigan (United States); McEwan, A.J.B. [University of Alberta, Cross Cancer Institute, Edmonton, Alberta (Canada); Robbins, K. Thomas [St. John' s Hospital Cancer Institute, Springfield, Illinois (United States); Grecula, John [Ohio State University Medical Center, Columbus, Ohio (United States); Sharma, Anand K. [Medical University of South Carolina, Charleston, South Carolina (United States); Ang, K. Kian [University of Texas MD Anderson Cancer Center, Houston, Texas (United States)

    2012-10-01

    Purpose: We report the results of a phase II study to determine the reproducibility of a submandibular salivary gland transfer (SGT) surgical technique for prevention of radiation (XRT)-induced xerostomia in a multi-institutional setting and to assess severity of xerostomia. Methods and Materials: Eligible patients had surgery for primary, neck dissection, and SGT, followed by XRT, during which the transferred salivary gland was shielded. Intensity modulated radiation therapy, amifostine, and pilocarpine were not allowed, but postoperative chemotherapy was allowed. Each operation was reviewed by 2 reviewers and radiation by 1 reviewer. If 13 or more (of 43) were 'not per protocol,' then the technique would be considered not reproducible as per study design. The secondary endpoint was the rate of acute xerostomia, grade 2 or higher, and a rate of {<=}51% was acceptable. Results: Forty-four of the total 49 patients were analyzable: male (81.8%), oropharynx (63.6%), stage IV (61.4%), median age 56.5 years. SGT was 'per protocol' or within acceptable variation in 34 patients (77.3%) and XRT in 79.5%. Nine patients (20.9%) developed grade 2 acute xerostomia; 2 had grade 0-1 xerostomia (4.7%) but started on amifostine/pilocarpine. Treatment for these 11 patients (25.6%) was considered a failure for the xerostomia endpoint. Thirteen patients died; median follow-up for 31 surviving patients was 2.9 years. Two-year overall and disease-free survival rates were 76.4% and 71.7%, respectively. Conclusions: The technique of submandibular SGT is reproducible in a multicenter setting. Seventy-four percent of patients were prevented from XRT-induced acute xerostomia.

  7. A Phase II Study of Submandibular Gland Transfer Prior to Radiation for Prevention of Radiation-induced Xerostomia in Head-and-Neck Cancer (RTOG 0244)

    International Nuclear Information System (INIS)

    Purpose: We report the results of a phase II study to determine the reproducibility of a submandibular salivary gland transfer (SGT) surgical technique for prevention of radiation (XRT)-induced xerostomia in a multi-institutional setting and to assess severity of xerostomia. Methods and Materials: Eligible patients had surgery for primary, neck dissection, and SGT, followed by XRT, during which the transferred salivary gland was shielded. Intensity modulated radiation therapy, amifostine, and pilocarpine were not allowed, but postoperative chemotherapy was allowed. Each operation was reviewed by 2 reviewers and radiation by 1 reviewer. If 13 or more (of 43) were “not per protocol,” then the technique would be considered not reproducible as per study design. The secondary endpoint was the rate of acute xerostomia, grade 2 or higher, and a rate of ≤51% was acceptable. Results: Forty-four of the total 49 patients were analyzable: male (81.8%), oropharynx (63.6%), stage IV (61.4%), median age 56.5 years. SGT was “per protocol” or within acceptable variation in 34 patients (77.3%) and XRT in 79.5%. Nine patients (20.9%) developed grade 2 acute xerostomia; 2 had grade 0-1 xerostomia (4.7%) but started on amifostine/pilocarpine. Treatment for these 11 patients (25.6%) was considered a failure for the xerostomia endpoint. Thirteen patients died; median follow-up for 31 surviving patients was 2.9 years. Two-year overall and disease-free survival rates were 76.4% and 71.7%, respectively. Conclusions: The technique of submandibular SGT is reproducible in a multicenter setting. Seventy-four percent of patients were prevented from XRT-induced acute xerostomia.

  8. Dry Mouth or Xerostomia

    Science.gov (United States)

    ... or Xerostomia Request Permissions Print to PDF Dry Mouth or Xerostomia Approved by the Cancer.Net Editorial ... a dry mouth. Signs and symptoms of dry mouth The signs and symptoms of dry mouth include ...

  9. Radiation induced currents in parallel plate ionization chambers: Measurement and Monte Carlo simulation for megavoltage photon and electron beams

    International Nuclear Information System (INIS)

    Polarity effects in ionization chambers are caused by a radiation induced current, also known as Compton current, which arises as a charge imbalance due to charge deposition in electrodes of ionization chambers. We used a phantom-embedded extrapolation chamber (PEEC) for measurements of Compton current in megavoltage photon and electron beams. Electron contamination of photon beams and photon contamination of electron beams have a negligible effect on the measured Compton current. To allow for a theoretical understanding of the Compton current produced in the PEEC effect we carried out Monte Carlo calculations with a modified user code, the COMPTON/EGSnrc. The Monte Carlo calculated COMPTON currents agree well with measured data for both photon and electron beams; the calculated polarity correction factors, on the other hand, do not agree with measurement results. The conclusions reached for the PEEC can be extended to parallel-plate ionization chambers in general

  10. Protective role of Carica papaya (Linn.) in electron beam radiation induced hematological and cytogenetic damages in Swiss albino mice

    International Nuclear Information System (INIS)

    Carica papaya (Linn.) is known to possess various biomedical applications. It has remarkable antioxidant properties. The main objective of the study was to evaluate the leaf extracts of Carica papaya (Linn.) on hematologic and cytogenetic changes occurring due to irradiation of mice to sub-lethal doses of Electron Beam Radiation (EBR). Analysis of hematological changes occurring due to irradiation of mice to sub-lethal doses of EBR, and the effects of Carica papaya (Linn.) extract on the same. The Assessment of hematopoietic stress by spleen colony forming unit and spleen body weight index. The analysis of cell proliferation and immunomodulation with response to the effects of Carica papaya (Linn.) extract by estimation of IL-6. The estimation of serum total antioxidants, lipid peroxidation and analyzing the activities of enzymes like SOD, ALP, and AST. Male Swiss albino mice were fed orally with papaya aqueous leaf extract for 15 days. They were irradiated with a whole body dose of 6 Gy Electron Beam radiation. The mice were dissected for liver, kidney, bone marrow, spleen and brain. The hematological studies were done using blood cell count in an automated cell counter. The biochemical estimations like urea, creatinine, SGOT, SGPT, Total Protein, Albumin, Bilirubin were done using the serum and homogenates. The total antioxidant capacity, the antioxidant enzymes were estimated. The Interleukin-6 levels were estimated in serum to assess immune modulation. The results show a decrease in the hematological parameters in radiated animals. The papaya treated groups have shown modulation in the hematological parameters. The extract has also reduced the suppression of the bone marrow induced by radiation. The radiation induced liver damage is also reduced in papaya treated groups. The aqueous extract of Carica papaya (Linn.) has shown protective effects in electron beam radiation induced tissue damages in Swiss Albino mice (author)

  11. Polymer electrolyte membranes for fuel cells by radiation induced grafting with electron beam irradiation: state-of-the-art

    International Nuclear Information System (INIS)

    Polymer electrolyte membranes have generated considerable interest in various fields of industrial interest due to their wide spread applications in fuel cells, batteries, electrolyzers sensors and actuators. Such diversity in applications implies a strong demand to architect the membranes towards particular properties for specific applications. Radiation induced grafting of vinyl and acrylic monomers into polymeric films, is an appealing method for producing various polymer electrolyte membranes. This method has the advantages of simplicity, controllability over the composition leading to tailored membrane properties and absence of shaping problem as preparation starts with substrate in a film form. It also has the flexibility of using various types of radiation sources such as gamma-rays and electron beam. Of all, electron beam (EB) accelerator is an advantageous source of high energy radiation that can initiate grafting reactions required for preparation of the membranes particularly when pilot scale production and commercial applications are sought. The grafting penetration can be varied from surface to bulk of membranes depending on the acceleration energy. This lecture reviews the-state of- the-art in the use of EB irradiation in preparation of composite and grafted polymer electrolyte membranes for fuel cell applications by radiation induced grafting with simultaneous irradiation and preirradiation methods. The use of simultaneous EB irradiation method was found to simplify the process and reduce the reaction time as well as the monomer consumption whereas the use of preirradiation method in a single-step route provides a shorter route to prepare polymer electrolyte membranes with improved properties and reduced cost in addition of setting basis for designing a continuous line to produce these membranes with dedicated EB facilities

  12. TH-E-BRF-09: Gaussian Mixture Model Analysis of Radiation-Induced Parotid-Gland Injury: An Ultrasound Study of Acute and Late Xerostomia in Head-And-Neck Radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Liu, T [Department of Radiation Oncology and Winship Cancer Institute, Emory Univ, Atlanta, GA (United States); Yu, D; Beitler, J; Curran, W; Yang, X [Department of Radiation Oncology and Winship Cancer Institute, Emory University, Atlanta, GA (United States); Tridandapani, S [Department of Radiology and Imaging Sciences and Winship Cancer Institute, Emory University, Atlanta, GA (United States); Bruner, D [School of Nursing and Winship Cancer Institute, Emory Univesity, Atlanta, GA (United States)

    2014-06-15

    Purpose: Xerostomia (dry mouth), secondary to parotid-gland injury, is a distressing side-effect in head-and-neck radiotherapy (RT). This study's purpose is to develop a novel ultrasound technique to quantitatively evaluate post-RT parotid-gland injury. Methods: Recent ultrasound studies have shown that healthy parotid glands exhibit homogeneous echotexture, whereas post-RT parotid glands are often heterogeneous, with multiple hypoechoic (inflammation) or hyperechoic (fibrosis) regions. We propose to use a Gaussian mixture model to analyze the ultrasonic echo-histogram of the parotid glands. An IRB-approved clinical study was conducted: (1) control-group: 13 healthy-volunteers, served as the control; (2) acutetoxicity group − 20 patients (mean age: 62.5 ± 8.9 years, follow-up: 2.0±0.8 months); and (3) late-toxicity group − 18 patients (mean age: 60.7 ± 7.3 years, follow-up: 20.1±10.4 months). All patients experienced RTOG grade 1 or 2 salivary-gland toxicity. Each participant underwent an ultrasound scan (10 MHz) of the bilateral parotid glands. An echo-intensity histogram was derived for each parotid and a Gaussian mixture model was used to fit the histogram using expectation maximization (EM) algorithm. The quality of the fitting was evaluated with the R-squared value. Results: (1) Controlgroup: all parotid glands fitted well with one Gaussian component, with a mean intensity of 79.8±4.9 (R-squared>0.96). (2) Acute-toxicity group: 37 of the 40 post-RT parotid glands fitted well with two Gaussian components, with a mean intensity of 42.9±7.4, 73.3±12.2 (R-squared>0.95). (3) Latetoxicity group: 32 of the 36 post-RT parotid fitted well with 3 Gaussian components, with mean intensities of 49.7±7.6, 77.2±8.7, and 118.6±11.8 (R-squared>0.98). Conclusion: RT-associated parotid-gland injury is common in head-and-neck RT, but challenging to assess. This work has demonstrated that the Gaussian mixture model of the echo-histogram could quantify acute and

  13. TH-E-BRF-09: Gaussian Mixture Model Analysis of Radiation-Induced Parotid-Gland Injury: An Ultrasound Study of Acute and Late Xerostomia in Head-And-Neck Radiotherapy

    International Nuclear Information System (INIS)

    Purpose: Xerostomia (dry mouth), secondary to parotid-gland injury, is a distressing side-effect in head-and-neck radiotherapy (RT). This study's purpose is to develop a novel ultrasound technique to quantitatively evaluate post-RT parotid-gland injury. Methods: Recent ultrasound studies have shown that healthy parotid glands exhibit homogeneous echotexture, whereas post-RT parotid glands are often heterogeneous, with multiple hypoechoic (inflammation) or hyperechoic (fibrosis) regions. We propose to use a Gaussian mixture model to analyze the ultrasonic echo-histogram of the parotid glands. An IRB-approved clinical study was conducted: (1) control-group: 13 healthy-volunteers, served as the control; (2) acutetoxicity group − 20 patients (mean age: 62.5 ± 8.9 years, follow-up: 2.0±0.8 months); and (3) late-toxicity group − 18 patients (mean age: 60.7 ± 7.3 years, follow-up: 20.1±10.4 months). All patients experienced RTOG grade 1 or 2 salivary-gland toxicity. Each participant underwent an ultrasound scan (10 MHz) of the bilateral parotid glands. An echo-intensity histogram was derived for each parotid and a Gaussian mixture model was used to fit the histogram using expectation maximization (EM) algorithm. The quality of the fitting was evaluated with the R-squared value. Results: (1) Controlgroup: all parotid glands fitted well with one Gaussian component, with a mean intensity of 79.8±4.9 (R-squared>0.96). (2) Acute-toxicity group: 37 of the 40 post-RT parotid glands fitted well with two Gaussian components, with a mean intensity of 42.9±7.4, 73.3±12.2 (R-squared>0.95). (3) Latetoxicity group: 32 of the 36 post-RT parotid fitted well with 3 Gaussian components, with mean intensities of 49.7±7.6, 77.2±8.7, and 118.6±11.8 (R-squared>0.98). Conclusion: RT-associated parotid-gland injury is common in head-and-neck RT, but challenging to assess. This work has demonstrated that the Gaussian mixture model of the echo-histogram could quantify acute and

  14. Radiation-induced myocardial perfusion abnormalities in breast cancer patients following external beam radiation therapy

    Directory of Open Access Journals (Sweden)

    Mohammad Eftekhari

    2015-01-01

    Full Text Available Objective(s: Radiation therapy for breast cancer can induce myocardial capillary injury and increase cardiovascular morbidity and mortality. A prospective cohort was conducted to study the prevalence of myocardial perfusion abnormalities following radiation therapy of left-sided breast cancer patients as compared to those with right–sided cancer. Methods: To minimize potential confounding factors, only those patients with low 10-year risk of coronary artery disease (based on Framingham risk scoring were included. All patients were initially treated by modified radical mastectomy and then were managed by postoperative 3D Conformal Radiation Therapy (CRT to the surgical bed with an additional 1-cm margin, delivered by 46-50 Gy (in 2 Gy daily fractions over a 5-week course. The same dose-adjusted chemotherapy regimen (including anthracyclines, cyclophosphamide and taxol was given to all patients. Six months after radiation therapy, all patients underwent cardiac SPECT for the evaluation of myocardial perfusion. Results: A total of 71 patients with a mean age of 45.3±7.2 years [35 patients with leftsided breast cancer (exposed and 36 patients with right-sided cancer (controls] were enrolled. Dose-volume histogram (DVH [showing the percentage of the heart exposed to >50% of radiation] was significantly higher in patients with left-sided breast cancer. Visual interpretation detected perfusion abnormalities in 42.9% of cases and 16.7% of controls (P=0.02, Odds ratio=1.46. In semiquantitative segmental analysis, only apical (28.6% versus 8.3%, P=0.03 and anterolateral (17.1% versus 2.8%, P=0.049 walls showed significantly reduced myocardial perfusion in the exposed group. Summed Stress Score (SSS of>3 was observed in twelve cases (34.3%, while in five of the controls (13.9%,(Odds ratio=1.3. There was no significant difference between the groups regarding left ventricular ejection fraction. Conclusion: The risk of radiation induced myocardial

  15. Photoluminescence of radiation-induced color centers in lithium fluoride thin films for advanced diagnostics of proton beams

    Energy Technology Data Exchange (ETDEWEB)

    Piccinini, M., E-mail: massimo.piccinini@enea.it; Ampollini, A.; Picardi, L.; Ronsivalle, C.; Bonfigli, F.; Libera, S.; Vincenti, M. A.; Montereali, R. M. [ENEA, C.R. Frascati, UTAPRAD, Technical Unit for Development and Applications of Radiations, Via E. Fermi 45, 00044 Frascati (Rome) (Italy); Ambrosini, F. [University Sapienza-Roma I, Piazzale Aldo Moro 5, 00185 Rome (Italy); Nichelatti, E. [ENEA, C.R. Casaccia, UTTMAT, Technical Unit for Materials Technologies, Via Anguillarese 301, 00123 S. Maria di Galeria (Rome) (Italy)

    2015-06-29

    Systematic irradiation of thermally evaporated 0.8 μm thick polycrystalline lithium fluoride films on glass was performed by proton beams of 3 and 7 MeV energies, produced by a linear accelerator, in a fluence range from 10{sup 11} to 10{sup 15} protons/cm{sup 2}. The visible photoluminescence spectra of radiation-induced F{sub 2} and F{sub 3}{sup +} laser active color centers, which possess almost overlapping absorption bands at about 450 nm, were measured under laser pumping at 458 nm. On the basis of simulations of the linear energy transfer with proton penetration depth in LiF, it was possible to obtain the behavior of the measured integrated photoluminescence intensity of proton irradiated LiF films as a function of the deposited dose. The photoluminescence signal is linearly dependent on the deposited dose in the interval from 10{sup 3} to about 10{sup 6 }Gy, independently from the used proton energies. This behavior is very encouraging for the development of advanced solid state radiation detectors based on optically transparent LiF thin films for proton beam diagnostics and two-dimensional dose mapping.

  16. Photoluminescence of radiation-induced color centers in lithium fluoride thin films for advanced diagnostics of proton beams

    International Nuclear Information System (INIS)

    Systematic irradiation of thermally evaporated 0.8 μm thick polycrystalline lithium fluoride films on glass was performed by proton beams of 3 and 7 MeV energies, produced by a linear accelerator, in a fluence range from 1011 to 1015 protons/cm2. The visible photoluminescence spectra of radiation-induced F2 and F3+ laser active color centers, which possess almost overlapping absorption bands at about 450 nm, were measured under laser pumping at 458 nm. On the basis of simulations of the linear energy transfer with proton penetration depth in LiF, it was possible to obtain the behavior of the measured integrated photoluminescence intensity of proton irradiated LiF films as a function of the deposited dose. The photoluminescence signal is linearly dependent on the deposited dose in the interval from 103 to about 106 Gy, independently from the used proton energies. This behavior is very encouraging for the development of advanced solid state radiation detectors based on optically transparent LiF thin films for proton beam diagnostics and two-dimensional dose mapping

  17. Electron beam radiation induced oxidative stress on alteration of enzymatic antioxidant status of Swiss albino mice

    International Nuclear Information System (INIS)

    Ionizing radiation causes damage to living tissues through a series of molecular events, such as photoelectric, Compton and Auger effects, depending on the radiation energy. Because human tissues contain 80% water, the major radiation damage is due to the aqueous free radicals, generated by the action of radiation on water. It was found to be 10 Gy was the lethal dose for mice. Different dosages (4 Gy, 6 Gy and 8 Gy) of electron beam radiation were used to study the level of lipid peroxidation and enzymatic antioxidant status of irradiated mice. The results showed higher the radiation dosage, increased lipid peroxidation and decreased antioxidant level. (author)

  18. Mesenchymal stem cell therapy for salivary gland dysfunction and xerostomia: a systematic review of preclinical studies

    DEFF Research Database (Denmark)

    Jensen, David Hebbelstrup; Oliveri, Roberto Stefan; Trojahn-Kølle, Stig-Frederik;

    2014-01-01

    was to assess, through systematic review, the potential benefit of mesenchymal stem cell (MSC) therapy in radiation-induced and SS-related salivary gland dysfunction and xerostomia. We searched PubMed/MEDLINE, Embase, Web of Science, the Cochrane Database of Systematic Reviews, the World Health Organization...... gland dysfunction and xerostomia. Nonetheless, the preliminary studies identified in the present review were encouraging for further research....

  19. The efficacy of Xialine[reg] in patients with xerostomia resulting from radiotherapy for head and neck cancer: a pilot-study

    International Nuclear Information System (INIS)

    Changes in subjective sensations due to xerostomia before and after administration of Xialine[reg], a xanthan gum-based saliva substitute, were evaluated in 30 patients with radiation-induced xerostomia using the QLQ-H and N35. Xerostomia in general decreased with both Xialine[reg] and placebo to almost the same degree. A trend was seen for Xialine[reg] to improve problems with speech and senses

  20. Unstimulated Salivary Flow Rate Corresponds with Severity of Xerostomia: Evaluation using Xerostomia Questionnaire and Groningen Radiotherapy- Induced Xerostomia Questionnaire

    OpenAIRE

    Friendika Dhiah Ayu Intan Shinta; Nushita Dinar; Hendri Susanto; Dewi Agustina

    2014-01-01

    One of the oral complications in head and neck radiotherapy is xerostomia. The severity of xerostomia can be observed using objective examination (unstimulated salivary flow rate measurement) and subjective examination (assessment using xerostomia questionnaires). There are two questionnaires used in assessment of xerostomia in head and neck cancer radiotherapy namely Xerostomia Questionnaire (XQ) and Groningen Radiotherapy-Induced Xerostomia Questionnaire (GRIX). Objective: To know the corre...

  1. Xerostomia induced by radiotherapy

    OpenAIRE

    Alimi, David

    2015-01-01

    David Alimi Department of Anesthesiology, University of Pittsburgh Medical Center, Pittsburgh, PA, USAWe read with great interest the excellent review on xerostomia induced by radiotherapy, by Pinna et al.1 The authors should be congratulated for a very detailed review of the physiopathology, clinical symptoms, and therapeutic management of an extremely difficult condition. Although we agree that the use of anticholinergic medication represents treatment, it requires the patient to have resi...

  2. Xerostomia Akibat Penggunaan Tramadol

    OpenAIRE

    Rinaningsih, Wahyu

    2008-01-01

    Xerostomia merupakan manifestasi klinik dimana menurunnya produksi saliva, dapat berupa jumlah ataupun viskositasnya. Keadaan ini merupakan suatu gejala dan bukan merupakan suatu penyakit, yang disebabkan oleh berbagai faktor. Salah satu faktor tersebut adalah pengaruh dari penggunaan obat tramadol. Tramadol adalah derivat sikloheksanol yang merupakan zat sintesis dari morfin, dan masuk dalam golongan analgetikum opioid karena bekerja sentral, yakni melalui pendudukan reseptor nyeri di SSP. O...

  3. [Xerostomia in palliative care].

    Science.gov (United States)

    Feio, Madalena; Sapeta, Paula

    2005-01-01

    Xerostomia is the subjective feeling of mouth dryness, caused or not by function lowering of salivary glands, with decrease of saliva quality or quantity. It's a frequent symptom in palliative care patients and its prevalence is referred to be 60% to 88% in advanced and progressive oncological disease patients. Xerostomia has physical, social and psychological consequences. Saliva plays an important role in maintaining the best physiological conditions of mouth. Besides humidifying the oral cavity tissues, its lubricating properties help swallowing, talking and prevents other damages caused by mechanical and noxious microbiological agents. Xerostomia is caused by three basic mechanisms: factors that compromise the salivary centre, factors related to the autonomic stimulation or factors related to salivary glands themselves. The diagnosis is mainly clinical. Mouth condition must be thoroughly evaluated. If justified, a quantitative evaluation of saliva secretion, in rest and under stimulation, might be done. The treatment must be oriented by aetiology and directed towards the disease effects in patient comfort and quality of life. During treatment, the use of xerogenic drugs should be controlled, hydration should be promoted and other symptom control measures improved. The symptomatic treatment has three pathways: the increasing of saliva production by mechanical, gustatory or pharmacological stimulation; the using of saliva substitutes and the improving of active mouth care. Mechanical stimulation is obtained by chewing gum and gustatory stimulation may be reached by sucking Vitamin C tablets. Pilocarpine is the available drug to improve salivation. A soft diet must be advised, hard and dry food, tobacco and alcoholic beverages should be avoided. It's important that health workers teach patients with xerostomia the best way to get relief and the measures to prevent its complications that could, even more, compromise their quality of life. PMID:16684486

  4. Xerostomia induced by radiotherapy: an overview of the physiopathology, clinical evidence, and management of the oral damage

    OpenAIRE

    Pinna, Roberto; Campus, Guglielmo Giuseppe; Cumbo, Enzo Maria Giuseppe; Mura, Ida Iolanda; Milia, Egle Patrizia

    2015-01-01

    Background: The irradiation of head and neck cancer (HNC) often causes damage to the salivary glands. The resulting salivary gland hypofunction and xerostomia seriously reduce the patient’s quality of life. Purpose: To analyze the literature of actual management strategies for radiation-induced hypofunction and xerostomia in HNC patients. Methods: MEDLINE/PubMed and the Cochrane Library databases were electronically evaluated for articles published from January 1, 1970, to June 30, 2013...

  5. Clinical Management of Salivary Gland Hypofunction and Xerostomia in Head-and-Neck Cancer Patients: Successes and Barriers

    International Nuclear Information System (INIS)

    The most significant long-term complication of radiotherapy in the head-and-neck region is hyposalivation and its related complaints, particularily xerostomia. This review addresses the pathophysiology underlying irradiation damage to salivary gland tissue, the consequences of radiation injury, and issues contributing to the clinical management of salivary gland hypofunction and xerostomia. These include ways to (1) prevent or minimize radiation injury of salivary gland tissue, (2) manage radiation-induced hyposalivation and xerostomia, and (3) restore the function of salivary gland tissue damaged by radiotherapy.

  6. Xerostomia induced by radiotherapy

    Directory of Open Access Journals (Sweden)

    Alimi D

    2015-08-01

    Full Text Available David Alimi Department of Anesthesiology, University of Pittsburgh Medical Center, Pittsburgh, PA, USAWe read with great interest the excellent review on xerostomia induced by radiotherapy, by Pinna et al.1 The authors should be congratulated for a very detailed review of the physiopathology, clinical symptoms, and therapeutic management of an extremely difficult condition. Although we agree that the use of anticholinergic medication represents treatment, it requires the patient to have residual salivary gland function. Unfortunately, it is well established that in most cases radiotherapy destroys most of the salivary gland and associated salivary secretions.     

  7. Synchrotron radiation induced x-ray micro analysis: A realistic alternative for electron- and ion beam microscopy?

    International Nuclear Information System (INIS)

    Synchrotron Radiation induced X-ray micro Fluorescence analysis (μ-SRXRF) is compared with more conventional microanalytical techniques such as Secondary Ion Microscopy (SIMS) and Electron Probe X-ray Microanalysis (EPXMA) for two typical microanalytical applications. SRXRF and EPXMA are employed for the analysis of individual particles, showing the complementary character of both techniques. By means of element mapping of trace constituents in a heterogeneous feldspar, the strong and weak points of SRXRF in comparison to EPXMA and SIMS are illustrated. The most striking difference between SRXRF and the other two microanalytical methods is the ability of SRXRF to probe deep into the investigated Material, whereas SIMS and EPXMA only investigate the upper surface of the material. The possibilities of SRXRF at third generation synchrotron rings is also briefly discussed

  8. Assessing the radiation-induced second cancer risk in proton therapy for pediatric brain tumors: the impact of employing a patient-specific aperture in pencil beam scanning

    Science.gov (United States)

    Geng, Changran; Moteabbed, Maryam; Xie, Yunhe; Schuemann, Jan; Yock, Torunn; Paganetti, Harald

    2016-01-01

    The purpose of this study was to compare the radiation-induced second cancer risks for in-field and out-of-field organs and tissues for pencil beam scanning (PBS) and passive scattering proton therapy (PPT) and assess the impact of adding patient-specific apertures to sharpen the penumbra in pencil beam scanning for pediatric brain tumor patients. Five proton therapy plans were created for each of three pediatric patients using PPT as well as PBS with two spot sizes (average sigma of ~17 mm and ~8 mm at isocenter) and choice of patient-specific apertures. The lifetime attributable second malignancy risks for both in-field and out-of-field tissues and organs were compared among five delivery techniques. The risk for in-field tissues was calculated using the organ equivalent dose, which is determined by the dose volume histogram. For out-of-field organs, the organ-specific dose equivalent from secondary neutrons was calculated using Monte Carlo and anthropomorphic pediatric phantoms. We find that either for small spot size PBS or for large spot size PBS, a patient-specific aperture reduces the in-field cancer risk to values lower than that for PPT. The reduction for large spot sizes (on average 43%) is larger than for small spot sizes (on average 21%). For out-of-field organs, the risk varies only marginally by employing a patient-specific aperture (on average from  -2% to 16% with increasing distance from the tumor), but is still one to two orders of magnitude lower than that for PPT. In conclusion, when pencil beam spot sizes are large, the addition of apertures to sharpen the penumbra decreases the in-field radiation-induced secondary cancer risk. There is a slight increase in out-of-field cancer risk as a result of neutron scatter from the aperture, but this risk is by far outweighed by the in-field risk benefit from using an aperture with a large PBS spot size. In general, the risk for developing a second malignancy in out-of-field organs for PBS remains

  9. Radiation-induced oxidation of ultra-high molecular weight polyethylene (UHMWPE) powder by gamma rays and electron beams: A clear dependence of dose rate

    Science.gov (United States)

    Wang, Honglong; Xu, Lu; Hu, Jiangtao; Wang, Mouhua; Wu, Guozhong

    2015-10-01

    Oxidation is an important effect of irradiation on polyethylene in air. In this work, oxidation of ultra-high molecular weight polyethylene (UHMWPE) powder (ca. 110 μm in diameter) induced by gamma rays (γ ray) and electron beams (EB) in air resulted in some large differences in properties, such as oxidative scission due to dose rate differences. However, other properties, such as surface wettability and thermal stability were not that greatly affected. The dose-rates used were 0.0019 kGy/s from a cobalt-60 gamma source and 92 kGy/s from an electron beam. The chemical structure, oxidation level, surface wettability and thermal stability of irradiated UHMWPE were analyzed by FT-IR, XPS, TGA and the static contact angle. Hydrophilic carboxyl and carbonyl groups were present on the surface of irradiated UHMWPE after irradiation in air, resulting in a decrease in the contact angle. After irradiation at 300 kGy, the gel content of the γ ray-irradiated UHMWPE samples decreased to almost zero, while that of EB irradiated UHMWPE decreased to 57%. For UHMWPE powder irradiated by gamma rays at lower doses, radiation-induced oxidation was complete and consistent with a simple theoretic estimation. Surface wettability was primarily affected by surface oxidation, and the oxidation level of UHMWPE could be easily predicted.

  10. Xerostomia: current streams of investigation.

    Science.gov (United States)

    Quock, Ryan L

    2016-07-01

    Xerostomia is the subjective feeling of dry mouth, and it is often related to salivary hypofunction. Besides medication-related salivary hypofunction, Sjögren syndrome and head-and-neck radiation are two common etiologies that have garnered considerable attention. Approaches to treating and/or preventing salivary hypofunction in patients with these conditions will likely incorporate gene therapy, stem cell therapy, and tissue engineering. Advances in these disciplines are central to current research in the cure for xerostomia and will be key to eventual treatment. PMID:27189896

  11. Preparation and mechanical properties of PLA-PEG copolymers modified by radiation-induced crosslinking of low energy electron beams

    International Nuclear Information System (INIS)

    PLA-PEG copolymer is wildly applied in medical and pharmaceutical fields, but its mechanical properties are not so good, such as the tensile intensity and elongation at break. To improve these properties, PLA-PEG copolymers were synthesized and irradiated using low energy electron beams (EB) with various irradiation doses in the presence of 3 wt% polyfunctional monomer (triallylcyanurate, TAC) as crosslinking agent to introduce crosslinking between polymer chains. It was found that with the increase of the irradiation doses, the tensile intensity of the PLA-PEG increased, while the elongation at break decreased, the most optimal irradiation dose was 80 kGy, the tensile intensity was 12.5 MPa and 19.9 MPa, corresponding to the elongation at break of 282.8 % and 28.7% for PLA9-PEG6 and PLA11-PEG6, respectively. Meanwhile, the solvent resistance of crosslinked sample was improved obviously at this dose. The crosslinked PLA-PEG copolymer can be applied to packaging materials, tubes and so on. (Author)

  12. Radiation-induced oxidation of ultra-high molecular weight polyethylene (UHMWPE) powder by gamma rays and electron beams: A clear dependence of dose rate

    International Nuclear Information System (INIS)

    Oxidation is an important effect of irradiation on polyethylene in air. In this work, oxidation of ultra-high molecular weight polyethylene (UHMWPE) powder (ca. 110 μm in diameter) induced by gamma rays (γ ray) and electron beams (EB) in air resulted in some large differences in properties, such as oxidative scission due to dose rate differences. However, other properties, such as surface wettability and thermal stability were not that greatly affected. The dose-rates used were 0.0019 kGy/s from a cobalt-60 gamma source and 92 kGy/s from an electron beam. The chemical structure, oxidation level, surface wettability and thermal stability of irradiated UHMWPE were analyzed by FT-IR, XPS, TGA and the static contact angle. Hydrophilic carboxyl and carbonyl groups were present on the surface of irradiated UHMWPE after irradiation in air, resulting in a decrease in the contact angle. After irradiation at 300 kGy, the gel content of the γ ray-irradiated UHMWPE samples decreased to almost zero, while that of EB irradiated UHMWPE decreased to 57%. For UHMWPE powder irradiated by gamma rays at lower doses, radiation-induced oxidation was complete and consistent with a simple theoretic estimation. Surface wettability was primarily affected by surface oxidation, and the oxidation level of UHMWPE could be easily predicted. - Highlights: • UHMWPE powder was irradiated by γ ray and EB in air with difference in dose rate. • Radiation oxidation was studied and compared experimentally and theoretically. • The dose rate has great effect on thickness of oxidation layer in UHMWPE powder

  13. Radiation-induced pneumothorax

    Energy Technology Data Exchange (ETDEWEB)

    Epstein, D.M.; Littman, P.; Gefter, W.B.; Miller, W.T.; Raney, R.B. Jr.

    1983-01-01

    Pneumothorax is an uncommon complication of radiation therapy to the chest. The proposed pathogenesis is radiation-induced fibrosis promoting subpleural bleb formation that ruptures resulting in pneumothorax. We report on two young patients with primary sarcomas without pulmonary metastases who developed spontaneous pneumothorax after irradiation. Neither patient had antecedent radiographic evidence of pulmonary fibrosis.

  14. Radiation-induced pneumothorax

    International Nuclear Information System (INIS)

    Pneumothorax is an uncommon complication of radiation therapy to the chest. The proposed pathogenesis is radiation-induced fibrosis promoting subpleural bleb formation that ruptures resulting in pneumothorax. We report on two young patients with primary sarcomas without pulmonary metastases who developed spontaneous pneumothorax after irradiation. Neither patient had antecedent radiographic evidence of pulmonary fibrosis

  15. Radiation Induced Fermion Resonance

    OpenAIRE

    Esposito, S.; M. W. Evans; Recami, E.

    1998-01-01

    The Dirac equation is solved for two novel terms which describe the interaction energy between the half integral spin of a fermion and the classical, circularly polarized, electromagnetic field. A simple experiment is suggested to test the new terms and the existence of radiation induced fermion resonance.

  16. Xerostomia induced by radiotherapy: an overview of the physiopathology, clinical evidence, and management of the oral damage

    Directory of Open Access Journals (Sweden)

    Pinna R

    2015-02-01

    Full Text Available Roberto Pinna,1 Guglielmo Campus,2 Enzo Cumbo,3 Ida Mura,1 Egle Milia2 1Department of Biomedical Science, 2Department of Surgery, Microsurgery and Medicine, University of Sassari, Sassari, 3Department of Dental Science, University of Palermo, Palermo, Italy Background: The irradiation of head and neck cancer (HNC often causes damage to the salivary glands. The resulting salivary gland hypofunction and xerostomia seriously reduce the patient’s quality of life. Purpose: To analyze the literature of actual management strategies for radiation-induced hypofunction and xerostomia in HNC patients. Methods: MEDLINE/PubMed and the Cochrane Library databases were electronically evaluated for articles published from January 1, 1970, to June 30, 2013. Two reviewers independently screened and included papers according to the predefined selection criteria. Results: Sixty-one articles met the inclusion criteria. The systematic review of the literature suggests that the most suitable methods for managing the clinical and pathophysiological consequences of HNC radiotherapy might be the pharmacological approach, for example, through the use of cholinergic agonists when residual secretory capacity is still present, and the use of salivary substitutes. In addition, a modified diet and the patient’s motivation to enhance oral hygiene can lead to a significant improvement. Conclusion: Radiation-induced xerostomia could be considered a multifactorial disease. It could depend on the type of cancer treatment and the cumulative radiation dose to the gland tissue. A preventive approach and the correct treatment of the particular radiotherapeutic patient can help to improve the condition of xerostomia. Keywords: radiation-induced xerostomia, salivary gland hypofunction, management strategies

  17. Study on radiation-induced reaction in microscopic region for basic understanding of electron beam patterning in lithographic process. 1. Development of subpicosecond pulse radiolysis and relation between space resolution and radiation-induced reactions of onium salt

    International Nuclear Information System (INIS)

    In the acid generation processes of chemically amplified electron beam and X-ray resists, the ionization of a base resin plays an important role. A proton is generated from the cation radical of the base resin. On the other hand, a counter anion is generated from an acid generator after the reaction of the acid generator with the electron generated by the ionization of the base resin. In the resist materials in which both the radical cation of base resin and the electron play important roles in forming a latent image, the initial separation distance between the cation radical and the electron and the subsequent reactions immediately after irradiation are important for the fabrication of nanoscale patterns. For the understanding of electron beam and X-ray patterning, we developed a subpicosecond pulse radiolysis system for conducting the absorption spectroscopy and investigated the reactions of onium salt. The onium salt efficiently reacts with an electron generated by ionization. The high efficiency of reaction of an onium salt with an electron is thought to block the migration of a thermalized electron in the resist matrix and prevent the degradation of the space resolution of resists caused by the migration of the thermalized electron. (author)

  18. Radiation induced oral mucositis

    OpenAIRE

    P S Satheesh Kumar; Anita Balan; Arun Sankar; Tinky Bose

    2009-01-01

    Patients receiving radiotherapy or chemotherapy will receive some degree of oral mucositis The incidence of oral mucositis was especially high in patients: (i) With primary tumors in the oral cavity, oropharynx, or nasopharynx; (ii) who also received concomitant chemotherapy; (iii) who received a total dose over 5,000 cGy; and (iv) who were treated with altered fractionation radiation schedules. Radiation-induced oral mucositis affects the quality of life of the patients and the family concer...

  19. Pathogenesis of salivary gland disease and xerostomia. The conception of Mikulicz's disease based on new knowledge

    International Nuclear Information System (INIS)

    This review focuses on two topics of salivary gland diseases regarding xerostomia. First, the pathogenesis and treatment of xerostomia after radiotherapy against head and neck cancer is discussed. It is well known that the extent of radiation-induced salivary dysfunction and mucositis depends on the radiation dose and field. Moreover, the balance in the defense system of oropharyngeal cavity alters after radiotherapy. This altered balance may impair the ability to maintain the stable immunological control mechanism. Second, the newly established concept about Mikulicz's disease is discussed. Recently, elevated IgG4 concentration in serum and prominent infiltrating by plasmacytes expressing IgG4 in the salivary glands in Mikulicz's disease were revealed. Mikulicz's disease is different from Sjoegren's syndrome, and may be a systemic IgG4-related plasmacytic disease. (author)

  20. BRIEF OVERVIEW OF XEROSTOMIA PROBLEM

    Directory of Open Access Journals (Sweden)

    S. O. Podvyaznikov

    2015-04-01

    Full Text Available The saliva is indispensable for preservation of healthy mouth and teeth, due to its composition and physical and chemical properties. Saliva preserves the teeth and favors their remineralization for account of afflux of irreplaceable minerals: calcium and phosphor. Due to contents of such epidermal growth factor it participates in tissue repair. The saliva contains the antibacterial, antiviral and antifungal drug resistance factors, suppressing the bacterial colonization of teeth and mucosa.Dry mouth (xerostomia results in development of stomatitis, periodontitis effects, increases a risk of infectious lesions of oral mucosa. The severest forms of such pathology (Degrees II–III are observed in the patients administered of X-ray therapy on head and neck area and in case of Sjogren’s syndrome, when the irreversible degenerative changes develop in эпителии salivary glands epithelium. Etiology and pathogenesis of xerostomia are not exhaustively studied yet, and treatment of such complex pathology is still symptomatic.

  1. Radiation-induced second primary cancer risks from modern external beam radiotherapy for early prostate cancer: impact of stereotactic ablative radiotherapy (SABR), volumetric modulated arc therapy (VMAT) and flattening filter free (FFF) radiotherapy

    Science.gov (United States)

    Murray, Louise J.; Thompson, Christopher M.; Lilley, John; Cosgrove, Vivian; Franks, Kevin; Sebag-Montefiore, David; Henry, Ann M.

    2015-02-01

    Risks of radiation-induced second primary cancer following prostate radiotherapy using 3D-conformal radiotherapy (3D-CRT), intensity-modulated radiotherapy (IMRT), volumetric modulated arc therapy (VMAT), flattening filter free (FFF) and stereotactic ablative radiotherapy (SABR) were evaluated. Prostate plans were created using 10 MV 3D-CRT (78 Gy in 39 fractions) and 6 MV 5-field IMRT (78 Gy in 39 fractions), VMAT (78 Gy in 39 fractions, with standard flattened and energy-matched FFF beams) and SABR (42.7 Gy in 7 fractions with standard flattened and energy-matched FFF beams). Dose-volume histograms from pelvic planning CT scans of three prostate patients, each planned using all 6 techniques, were used to calculate organ equivalent doses (OED) and excess absolute risks (EAR) of second rectal and bladder cancers, and pelvic bone and soft tissue sarcomas, using mechanistic, bell-shaped and plateau models. For organs distant to the treatment field, chamber measurements recorded in an anthropomorphic phantom were used to calculate OEDs and EARs using a linear model. Ratios of OED give relative radiation-induced second cancer risks. SABR resulted in lower second cancer risks at all sites relative to 3D-CRT. FFF resulted in lower second cancer risks in out-of-field tissues relative to equivalent flattened techniques, with increasing impact in organs at greater distances from the field. For example, FFF reduced second cancer risk by up to 20% in the stomach and up to 56% in the brain, relative to the equivalent flattened technique. Relative to 10 MV 3D-CRT, 6 MV IMRT or VMAT with flattening filter increased second cancer risks in several out-of-field organs, by up to 26% and 55%, respectively. For all techniques, EARs were consistently low. The observed large relative differences between techniques, in absolute terms, were very low, highlighting the importance of considering absolute risks alongside the corresponding relative risks, since when absolute

  2. Radiation-induced second primary cancer risks from modern external beam radiotherapy for early prostate cancer: impact of stereotactic ablative radiotherapy (SABR), volumetric modulated arc therapy (VMAT) and flattening filter free (FFF) radiotherapy

    International Nuclear Information System (INIS)

    Risks of radiation-induced second primary cancer following prostate radiotherapy using 3D-conformal radiotherapy (3D-CRT), intensity-modulated radiotherapy (IMRT), volumetric modulated arc therapy (VMAT), flattening filter free (FFF) and stereotactic ablative radiotherapy (SABR) were evaluated. Prostate plans were created using 10 MV 3D-CRT (78 Gy in 39 fractions) and 6 MV 5-field IMRT (78 Gy in 39 fractions), VMAT (78 Gy in 39 fractions, with standard flattened and energy-matched FFF beams) and SABR (42.7 Gy in 7 fractions with standard flattened and energy-matched FFF beams). Dose-volume histograms from pelvic planning CT scans of three prostate patients, each planned using all 6 techniques, were used to calculate organ equivalent doses (OED) and excess absolute risks (EAR) of second rectal and bladder cancers, and pelvic bone and soft tissue sarcomas, using mechanistic, bell-shaped and plateau models. For organs distant to the treatment field, chamber measurements recorded in an anthropomorphic phantom were used to calculate OEDs and EARs using a linear model. Ratios of OED give relative radiation-induced second cancer risks. SABR resulted in lower second cancer risks at all sites relative to 3D-CRT. FFF resulted in lower second cancer risks in out-of-field tissues relative to equivalent flattened techniques, with increasing impact in organs at greater distances from the field. For example, FFF reduced second cancer risk by up to 20% in the stomach and up to 56% in the brain, relative to the equivalent flattened technique. Relative to 10 MV 3D-CRT, 6 MV IMRT or VMAT with flattening filter increased second cancer risks in several out-of-field organs, by up to 26% and 55%, respectively. For all techniques, EARs were consistently low. The observed large relative differences between techniques, in absolute terms, were very low, highlighting the importance of considering absolute risks alongside the corresponding relative risks, since when absolute

  3. Chemical Induced Xerostomia Among Institutionalized Eldery

    OpenAIRE

    Petrovski, Mihajlo; Minovska, Ana; Ivanovski, Kiro; Forna, Doriana Agop; Forna, Consuela Norna

    2015-01-01

    Subjective presence of dry mouth is most common oral problem among the institutionalized elderly. To assess the subjective presence of xerostomia among institutionalized elderly. Total numbers of 70 subjects older than 65 years institutionalized in one nursing home were evaluated. The subjective presence of xerstomia was determinated. To determine the level of expressiveness of xerostomia is used questionnaire recommended by Carda et al. 62.8% from the subjects believed that they ...

  4. Studies on acupuncture treatment of xerostomia

    OpenAIRE

    Blom, Maria

    1999-01-01

    Xerostomia (dry mouth) is most often associated with Sjögren's Syndrome (SS), medication, endocrinological disorders, or irradiation treatment to the head- and neck region. There is no effective treatment of xerostomia at the present. Only alleviating methods are used, such as saliva substitutes, saliva stimulating agents, chewing gum, pilocarpine, and electrical stimulation; however, these methods give only a short-term relief. Acupuncture, one of many methods of sensory st...

  5. Radiation induced pesticidal microbes

    International Nuclear Information System (INIS)

    To isolate pesticidal microbes against plant pathogenic fungi, 4 strains of bacteria(K1. K3, K4, YS1) were isolated from mushroom compost and hot spring. K4, K1, K3, YS1 strain showed wide antifungal spectrum and high antifungal activities against 12 kinds of fungi. Specific proteins and the specific transcribed genes were found from the YS1 and its radiation-induced mutants. And knock-out mutants of antifungal activity were derived by transposon mutagenesis. From these knock-out mutants, the antifungal activity related genes and its modification by gamma-ray radiation are going to be studied. These results suggested that radiation could be an useful tool for the induction of functional mutants

  6. Radiation induced oral mucositis

    Directory of Open Access Journals (Sweden)

    P S Satheesh Kumar

    2009-01-01

    Full Text Available Patients receiving radiotherapy or chemotherapy will receive some degree of oral mucositis The incidence of oral mucositis was especially high in patients: (i With primary tumors in the oral cavity, oropharynx, or nasopharynx; (ii who also received concomitant chemotherapy; (iii who received a total dose over 5,000 cGy; and (iv who were treated with altered fractionation radiation schedules. Radiation-induced oral mucositis affects the quality of life of the patients and the family concerned. The present day management of oral mucositis is mostly palliative and or supportive care. The newer guidelines are suggesting Palifermin, which is the first active mucositis drug as well as Amifostine, for radiation protection and cryotherapy. The current management should focus more on palliative measures, such as pain management, nutritional support, and maintenance, of good oral hygiene

  7. Radiation induced pesticidal microbes

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ki Yup; Lee, Y. K.; Kim, J. S.; Kim, J. K.; Lee, S. J.; Lim, D. S

    2001-01-01

    To isolate pesticidal microbes against plant pathogenic fungi, 4 strains of bacteria(K1. K3, K4, YS1) were isolated from mushroom compost and hot spring. K4, K1, K3, YS1 strain showed wide antifungal spectrum and high antifungal activities against 12 kinds of fungi. Specific proteins and the specific transcribed genes were found from the YS1 and its radiation-induced mutants. And knock-out mutants of antifungal activity were derived by transposon mutagenesis. From these knock-out mutants, the antifungal activity related genes and its modification by gamma-ray radiation are going to be studied. These results suggested that radiation could be an useful tool for the induction of functional mutants.

  8. [Radiation-induced cancers].

    Science.gov (United States)

    Dutrillaux, B

    1998-01-01

    The induction of malignant diseases is one of the most concerning late effects of ionising radiation. A large amount of information has been collected form atomic bomb survivors, patients after therapeutic irradiation, occupational follow-up and accidentally exposed populations. Major uncertainties persist in the (very) low dose range i.e., population and workers radioprotection. A review of the biological mechanisms leading to cancer strongly suggests that the vast majority of radiation-induced malignancies arise as a consequence of recessive mutations of tumour-suppressor genes. These mutations can be unveiled by ageing, this process being possibly furthered by constitutional or acquired genomic instability. The individual risk is likely to be very low, probably because of the usual dose level. However, the magnitude of medical exposure and the reliance of our societies on nuclear industry are so high that irreproachable decision-making processes and standards for practice are inescapable. PMID:9868399

  9. Radiation-induced hydrogen transfer in metals

    Science.gov (United States)

    Tyurin, Yu I.; Vlasov, V. A.; Dolgov, A. S.

    2015-11-01

    The paper presents processes of hydrogen (deuterium) diffusion and release from hydrogen-saturated condensed matters in atomic, molecular and ionized states under the influence of the electron beam and X-ray radiation in the pre-threshold region. The dependence is described between the hydrogen isotope release intensity and the current density and the electron beam energy affecting sample, hydrogen concentration in the material volume and time of radiation exposure to the sample. The energy distribution of the emitted positive ions of hydrogen isotopes is investigated herein. Mechanisms of radiation-induced hydrogen transfer in condensed matters are suggested.

  10. RIS - radiation induced superheroes

    International Nuclear Information System (INIS)

    We all know & love our Superheroes. Whether we realised it or not when we were kids growing up watching or reading 'Faster than a locomotive...' or ...'he does whatever a spider can...' , the fantasy of these cool hero characters was created, in one way or another, by the influence of RADIATION. Our Radiation Induced Superheroes include such greats as Superman, Spiderman & the Incredible Hulk. There were other lesser known ones which didn't make the cut with this 'bit of fun' poster. Others include names like The Fantastic Four: Mr Fantastic, The Invisible Woman, The Human Torch & Thing - all exposed to high-level cosmic radiation during an outer space scientific mission. Superpowers such as the element of 'Radiation Control' are available to characters like Metallo - a Superman adversary & Ultron - a baddie in the Avengers comics. We all know that the physics makes these characters complete works of fiction, but it's fun to watch their TV shows (Superman is STILL on TV in 'Smallville'), movies go without saying - dozens of them around & still being created & some of us even still read the comics!

  11. Coupling of Geant4-DNA physics models into the GATE Monte Carlo platform: Evaluation of radiation-induced damage for clinical and preclinical radiation therapy beams

    Science.gov (United States)

    Pham, Q. T.; Anne, A.; Bony, M.; Delage, E.; Donnarieix, D.; Dufaure, A.; Gautier, M.; Lee, S. B.; Micheau, P.; Montarou, G.; Perrot, Y.; Shin, J. I.; Incerti, S.; Maigne, L.

    2015-06-01

    The GATE Monte Carlo simulation platform based on the Geant4 toolkit is in constant improvement for dosimetric calculations. In this paper, we present the integration of Geant4-DNA processes into the GATE 7.0 platform in the objective to perform multi-scale simulations (from macroscopic to nanometer scale). We simulated three types of clinical and preclinical beams: a 6 MeV electron clinical beam, a X-ray irradiator beam and a clinical proton beam for which we validated depth dose distributions against measurements in water. Frequencies of energy depositions and DNA damage were evaluated using a specific algorithm in charge of allocating energy depositions to atoms constituting DNA molecules represented by their PDB (Protein Data Bank) description.

  12. Coupling of Geant4-DNA physics models into the GATE Monte Carlo platform: Evaluation of radiation-induced damage for clinical and preclinical radiation therapy beams

    International Nuclear Information System (INIS)

    The GATE Monte Carlo simulation platform based on the Geant4 toolkit is in constant improvement for dosimetric calculations. In this paper, we present the integration of Geant4-DNA processes into the GATE 7.0 platform in the objective to perform multi-scale simulations (from macroscopic to nanometer scale). We simulated three types of clinical and preclinical beams: a 6 MeV electron clinical beam, a X-ray irradiator beam and a clinical proton beam for which we validated depth dose distributions against measurements in water. Frequencies of energy depositions and DNA damage were evaluated using a specific algorithm in charge of allocating energy depositions to atoms constituting DNA molecules represented by their PDB (Protein Data Bank) description

  13. Coupling of Geant4-DNA physics models into the GATE Monte Carlo platform: Evaluation of radiation-induced damage for clinical and preclinical radiation therapy beams

    Energy Technology Data Exchange (ETDEWEB)

    Pham, Q.T.; Anne, A.; Bony, M.; Delage, E. [Clermont Université, Université Blaise Pascal, CNRS/IN2P3, Laboratoire de Physique Corpusculaire, BP 10448, F-63000 Clermont-Ferrand (France); Donnarieix, D. [Centre Jean Perrin, Service de physique médicale, 58 rue Montalembert, 63011 Clermont-Ferrand Cedex (France); Dufaure, A.; Gautier, M. [Clermont Université, Université Blaise Pascal, CNRS/IN2P3, Laboratoire de Physique Corpusculaire, BP 10448, F-63000 Clermont-Ferrand (France); Lee, S.B. [Proton Therapy Center, National Cancer Center, 323 Ilsan-ro, Ilsandong-gu, Goyang-si, Gyeonggi-do 410-769 (Korea, Republic of); Micheau, P.; Montarou, G.; Perrot, Y. [Clermont Université, Université Blaise Pascal, CNRS/IN2P3, Laboratoire de Physique Corpusculaire, BP 10448, F-63000 Clermont-Ferrand (France); Shin, J.I. [Proton Therapy Center, National Cancer Center, 323 Ilsan-ro, Ilsandong-gu, Goyang-si, Gyeonggi-do 410-769 (Korea, Republic of); Incerti, S. [Université de Bordeaux, Centre d’Études Nucléaires de Bordeaux-Gradignan, UMR-5797, Chemin du Solarium, 33175 Gradignan (France); CNRS-IN2P3, Centre d’Études Nucléaires de Bordeaux-Gradignan, UMR-5797, Chemin du Solarium, 33175 Gradignan (France); Maigne, L., E-mail: maigne@clermont.in2p3.fr [Clermont Université, Université Blaise Pascal, CNRS/IN2P3, Laboratoire de Physique Corpusculaire, BP 10448, F-63000 Clermont-Ferrand (France)

    2015-06-15

    The GATE Monte Carlo simulation platform based on the Geant4 toolkit is in constant improvement for dosimetric calculations. In this paper, we present the integration of Geant4-DNA processes into the GATE 7.0 platform in the objective to perform multi-scale simulations (from macroscopic to nanometer scale). We simulated three types of clinical and preclinical beams: a 6 MeV electron clinical beam, a X-ray irradiator beam and a clinical proton beam for which we validated depth dose distributions against measurements in water. Frequencies of energy depositions and DNA damage were evaluated using a specific algorithm in charge of allocating energy depositions to atoms constituting DNA molecules represented by their PDB (Protein Data Bank) description.

  14. Radiation induced nano structures

    International Nuclear Information System (INIS)

    Full text: Nanometer-size silicon clusters have been attracting much attention due to their technological importance, in particular, as promising building blocks for nano electronic and nano photonic systems. Particularly, silicon wires are of great of interest since they have potential for use in one-dimensional quantum wire high-speed field effect transistors and light-emitting devices with extremely low power consumption. Carbon and metal nano structures are studied very intensely due to wide possible applications. Radiation material sciences have been dealing with sub-micron objects for a long time. Under interaction of high energy particles and ionizing radiation with solids by elastic and inelastic mechanisms, at first point defects are created, then they form clusters, column defects, disordered regions (amorphous colloids) and finally precipitates of another crystal phase in the matrix. Such irradiation induced evolution of structure defects and phase transformations was observed by X-diffraction techniques in dielectric crystals of quartz and corundum, which exist in and crystal modifications. If there is no polymorphism, like in alkali halide crystals, then due to radiolysis halogen atoms are evaporated from the surface that results in non-stoichiometry or accumulated in the pores formed by metal vacancies in the sub-surface layer. Nano-pores are created by intensive high energy particles irradiation at first chaotically and then they are ordered and in part filled by inert gas. It is well-known mechanism of radiation induced swelling and embrittlement of metals and alloys, which is undesirable for construction materials for nuclear reactors. Possible solution of this problem may come from nano-structured materials, where there is neither swelling nor embrittlement at gas absorption due to very low density of the structure, while strength keeps high. This review considers experimental observations of radiation induced nano-inclusions in insulating

  15. Evaluation of xerostomia following 3 dimensional conformal radiotherapy for nasopharyngeal cancer patients

    International Nuclear Information System (INIS)

    This study is to evaluate the xerostomia following 3-dimensional conformal radiation therapy (3D CRT) in nasopharynx cancer patients using the xerostomia questionnaire score (XQS). Questionnaire study was done on 51 patients with nasopharynx cancer who received 3D CRT from Dec. 2000 to Aug. 2005. 3D CRT technique is based on 'serial shrinking field' concept by 3 times of computed tomography (CT) simulation. Total target dose to the primary tumor was 72 Gy with 1.8 Gy daily fractions. Xerostomia was assessed with 4-questions XQS, and the associations between XQS and time elapsed after RT, age, sex, stage, concurrent chemotherapy, an parotid dose were analyzed. Concurrent chemotherapy was given to 40 patients and RT alone was given to 11 patients. The median time elapsed after 3D CRT was 20 (1 ∼ 58) months and the mean XQS of all 51 patients was 8.4 ± 1.9 (6 ∼ 14). XQS continuously and significantly decreased over time after 3D CRT (χ 2 -0.484, ρ < 0.05). There was no significant difference in XQS according to sex, age, and stag. However, XQS of concurrent chemotherapy patients was significantly higher than RT alone patients (ρ = 0.001). XQS of patients receiving total mean parotid dose ≥ 35 Gy was significantly higher than < 35 Gy (ρ = 0.05). Decreasing tendency of XQS over time after 3D CRT was observed. Concurrent chemotherapy and total mean parotid dose ≥ 35 Gy were suggested to adversely affect radiation-induced xerostomia

  16. Ionizing radiation induced cataract

    International Nuclear Information System (INIS)

    Until recently it was believed that the cataract (opacity of the eye lens) is a deterministic effect with a dose threshold of several Gray in dependence on the exposure conditions. Studies in Hiroshima and Nagasaki, in the vicinity of Chernobyl, of American radiologic technologists, astronauts, and patients after having received several computer tomographies of the head region, however, have shown that this assumption is not correct. It had been overlooked in the past that with decreasing dose the latency period is increasing. Therefore, the originally available studies were terminated too early. The more recent studies show that, in the case of a threshold existing at all, it is definitely below 0.8 Gy independently of an acute or a chronic exposure. All studies, however, include 0 Gy in the confidence interval, so that the absence of a dose threshold cannot be excluded. The German Commission on Radiological Protection (Strahlenschutzkommission, SSK) suggested therefore among others: targeted recording of the lens dose during activities which are known to be associated with possible significant lens exposure, examination of the lens should be included as appropriate in the medical monitoring of people occupationally exposed to radiation, if there is potentially high lens exposure, adoption of research strategies to develop a basic understanding of the mechanisms underlying radiation induced cataracts. The International Commission on Radiological Protection (ICRP) actually assumes a threshold dose of 0.5 Gy and, based on this assumption, has recommended in 2011 to reduce the dose limit for the eye lens from 150 mSv in a year to 20 mSv in a year for people occupationally exposed to ionising radiation. (orig.)

  17. Radiation induced diarrhoea - literature review

    International Nuclear Information System (INIS)

    Radiation-induced diarrhoea is an acute side effect of radiotherapy treatment to the pelvic area, experienced by nearly all patients. This paper will explore the patho-physiological rationale of diarrhoea, the causes of radiation-induced diarrhoea, the factors that influence the severity and occurrence, and the treatment of diarrhoea in relation to the radiotherapy setting, by analysing the current literature and will conclude by outlining future directions in this field. Copyright (2004) Australian Institute of Radiography

  18. XEROSTOMIA: FAKTOR ETIOLOGI, ETIOLOGI DAN PENANGGULANGAN

    Directory of Open Access Journals (Sweden)

    Sayuti Hasibuan

    2015-08-01

    Full Text Available Saliva is a complex oral secretion, which producd by major and minor salivary glans about 1.5 liters in 24 hours. In the oral cavity, saliva has several important functions include cleansing action, lubrication, facilitates for chewing and swallowing, food, speaking, buffer system.protecting teeth and a paart of mucosal immune system. These functions will be optimum if salivary secretion produced in normal quantitiy and quality. When salivary flow is diminished, it may express disorder in the form of xerostomia or oral dryness. Several factors can contribute as causing this condition, such as radiation to head and neck region, local diseases that affect salivary gland, systemic diseases, side effect of drugs and age. There are many problems usually presented by patients with xerostomia. These problems reflect the major funcitonal roles of saliva. So, the dentist must know the management of xerostomic patients, that aimed at elimination of the etiology of xerostomia, clinical manifestationsa and the management of xerostomia so that the dentist can arrange treatment planning rationally.id

  19. Radiation induced femoral palsy

    International Nuclear Information System (INIS)

    We report four cases of femoral palsy due to compressive fibrosis, after pelvic radiation therapy. Three patients had Hodgkin's disease, and one testicular seminoma. Prominent clinical features include major groin induration and underlying swelling. Unlike what is usually seen in tumoral relapse, little or no pain is associated with these neuropathies. The femoral post-radic palsy develops earlier and faster than brachial plexus palsy of same aetiology. In one case, progressive aggravation led to surgical neurolysis which resulted in dramatic and long lasting improvement. The principal preventive and therapeutic managements are discussed: since compressive fibrosis is related to the use of isolated and massive electron beam therapy, various association of cobalt and electron beam therapy are designed to best prevent the side effects of each of these methods. The early treatment of developing fibrosis by D. penicillamine is discussed

  20. Xerostomia: A day and night difference

    International Nuclear Information System (INIS)

    Purpose: To compare patient-reported xerostomia during daytime and during nighttime with objectively measured parotid and submandibular gland function in a cohort of head-and-neck cancer (HNC) patients treated with RT. Materials and methods: A cohort of 138 HNC patients underwent objective measurements of parotid (PF) and submandibular (SMF) gland function and completed a xerostomia questionnaire (XQ) before RT, at 6 weeks, 6 months and 1 year after RT. No attempt was made to spare the submandibular gland(s). The XQ contained specific questions concerning the sensation of dry mouth during day- (XD) and nighttime (XN), scored on a 5-point Likert scale. Patients with no or mild (grade 1–3) xerostomia and patients with more severe (grade 4–5) complaints were grouped together. Results: Before RT, no association existed between dry mouth complaints and PF or SMF. At 6 weeks, 6 months and 1 year after RT; 37%, 51% and 36% had grade 4–5 XD and 65%, 64% and 56% had grade 4–5 XN, respectively. Patients with grade 4–5 XD and XN had significantly worse SMF at all time points after RT compared to patients with grade 1–3 XD and XN, while PF was significantly worse only at 6 weeks after RT. In multivariate analyses, SMF was consistently the most important factor related to XN after treatment. PF significantly influenced XD at 6 weeks and 1 year after RT. Conclusions: Differentiating between complaints during day- and nighttime in xerostomia research is necessary. Dry mouth at night is a frequent problem after (parotid-sparing) RT for HNC and is explained by submandibular gland dysfunction. Sparing of the contralateral submandibular gland, in addition to parotid gland sparing, may result in improved patient-reported xerostomia.

  1. D-methionine as a protector for heavy ion radiation-induced oral mucositis. Evaluation of RBE of carbon-ion beams for epithelial thickness on mouse tongues

    International Nuclear Information System (INIS)

    To evaluate if D-methionine, the dextro-isomer of the common amino acid L-methionine, can prevent oral mucositis resulting from heavy ion irradiation during treatment for head and neck cancers. For the first study, relative biological effectiveness (RBE) of carbon-ion beams for epithelial thickness on mouse tongues was evaluated. The head of female C3H mice, 8 weeks old, were irradiated by five fractionated doses of carbon ion beams (290 MeV/u) or 150 kV X-rays to induce oral mucositis (ulcers on tongue). Six days after the last irradiation, mice were sacrificed. Excised tongues were evaluated macroscopically and microscopically. The thickness of the lingual epithelium was measured. The RBE of 6-cm spread-out Bragg peak (SOBP) (290 MeV/u) for epithelium on mouse tongues after fractionated doses is 1.82. It was almost the equivalent value as that for gut crypt survivals reported by enormous studies. (author)

  2. Radiation-induced intestinal inflammation

    Institute of Scientific and Technical Information of China (English)

    Meritxell Mollà; Julián Panés

    2007-01-01

    Radiation induces an important inflammatory response in the irradiated organs, characterized by leukocyte infiltration and vascular changes that are the main limiting factor in the application of this therapeutic modality for the treatment of cancer. Recently, a considerable investigative effort has been directed at determining the molecular mechanisms by which radiation induces leukocyte recruitment, in order to create strategies to prevent intestinal inflammatory damage. In these review, we consider current available evidence on the factors governing the process of leukocyte recruitment in irradiated organs, mainly derived from experimental studies, with special attention to adhesion molecules, and their value as therapeutic targets.

  3. In vitro studies to evaluate the protective effects of Cassia fistula on electron beam radiation induced damages in human dermal fibroblasts

    International Nuclear Information System (INIS)

    Radiation is increasingly used for medical and occupational purposes and is an established weapon in the diagnosis and the therapy of cancer. Cassia fistula, a member of the Leguminosae family, it is used as a traditional medicine specially to treat the skin diseases. The main objective of the study was to evaluate the changes induced by different doses of Electron Beam radiation on Human Dermal Fibroblasts (HDF) and protective effects of Cassia fistula on the same. Aqueous, methanolic and ethonolic extracts of Cassia fistula were prepared. In vitro biochemical assays like DPPH radical scavenging assay, Ferric Anion Reducing Potential using TPTZ, Nitric Oxide scavenging assay. Total antioxidant determination assay, Super Anion Radical Scavenging assays were carried out to study the antioxidant properties. HDF cells were standardized and treated with the Cassia fistula MTT assay was performed. Cells were irradiated and MTT, Micronucleus (MN) assays were performed then compared with control and non-irradiated cells. Cells were treated with Cassia fistula and irradiated; MTT and MN were performed. On comparison with the standard Ascorbic acid, ethanolic extract of Cassia fistula was showing 90% activity. The ethanolic extract of Cassia fistula is having high EC50 value. On comparison to the standard the alcoholic extracts of Cassia fistula has shown a higher FRAP value. Aqueous extract of Cassia fistula has minimum Nitric oxide scavenging property compared to alcoholic extracts. Methanolic and ethanolic extracts of Cassia fistula has shown 38-40% of Superoxide Radical Scavenging property in 500 μg/mL concentration. Also ethanolic and methanolic extracts of Cassia fistula has remarkable antioxidant property. Hence these concentrations were selected for further studies. Human Dermal Fibroblast cells were treated with the 500 μg/ mL of alcoholic Cassia fistula extracts which showed a protection against irradiated groups. (author)

  4. Xerostomia in the Geriatric Patient: Causes, Oral Manifestations, and Treatment.

    Science.gov (United States)

    Ouanounou, Aviv

    2016-05-01

    Xerostomia, or dry mouth, is common among elderly people and is typically associated with decreased salivary gland function. Causes of xerostomia in the geriatric population have been attributed to the use of medications, chronic disorders, and radiation therapy to the head and neck region. Patients with chronic xerostomia may have multiple oral and dental consequences such as dental caries, periodontal disease, fungal infections, ill-fitting dentures, and taste alterations. Xerostomia can seriously impact quality of life and may alter speech, eating, and swallowing. Current therapeutics for the management of xerostomia are grouped as local and systemic salivary stimulation. This article reviews the main reasons for xerostomia and the complications it causes in the oral cavity. It also discusses the pharmacologic and nonpharmacologic agents used to treat this condition. PMID:27213776

  5. Data acquisition system used in radiation induced electrical degradation experiments

    Energy Technology Data Exchange (ETDEWEB)

    White, D.P. [Oak Ridge National Lab., TN (United States)

    1995-04-01

    Radiation induced electrical degradation (RIED) of ceramic materials has recently been reported and is the topic of much research at the present time. The object of this report is to describe the data acquisition system for an experiment designed to study RIED at the High Flux Beam Reactor (HFBR) at Brookhaven National Laboratory.

  6. XEROSTOMIA: RECOGNITION, DENTAL IMPLICATION AND ITS MANAGEMENT

    OpenAIRE

    Jameel Ahmad; Khan

    2013-01-01

    ABSTRACT: Xerostomia commonly called as dry mouth, is the sub jective feeling of oral dryness. It is not a diagnosis, but a symptom with multiple pos sible causes. Although dry mouth is most frequently associated with altered salivary gland f unction, there are other etiologies for this condition. The most frequent cause of dry mouth complaints is t he use of certain drugs, depression or psychological conditions, systemic dise ases, radiotherapy etc. It is imp...

  7. Metabolic Imaging Biomarkers of Postradiotherapy Xerostomia

    Energy Technology Data Exchange (ETDEWEB)

    Cannon, Blake [Department of Radiation Physics, University of Texas M. D. Anderson Cancer Center, Houston, Texas (United States); Schwartz, David L., E-mail: dschwartz3@nshs.edu [Department of Radiation Oncology, University of Texas M. D. Anderson Cancer Center, Houston, Texas (United States); Department of Radiation Medicine, Hofstra North Shore-LIJ School of Medicine, New Hyde Park, New York (United States); Feinstein Institute for Medical Research, Manhasset, New York (United States); Dong Lei [Department of Radiation Physics, University of Texas M. D. Anderson Cancer Center, Houston, Texas (United States)

    2012-08-01

    Purpose: Xerostomia is a major complication of head and neck radiotherapy (RT). Available xerostomia measures remain flawed. [{sup 18}F]fluorodeoxyglucose-labeled positron emission tomography-computed tomography (FDG-PET-CT) is routinely used for staging and response assessment of head and neck cancer. We investigated quantitative measurement of parotid gland FDG uptake as a potential biomarker for post-RT xerostomia. Methods and Materials: Ninety-eight locally advanced head and neck cancer patients receiving definitive RT underwent baseline and post-RT FDG-PET-CT on a prospective imaging trial. A separate validation cohort of 14 patients underwent identical imaging while prospectively enrolled in a second trial collecting sialometry and patient-reported outcomes. Radiation dose and pre- and post-RT standard uptake values (SUVs) for all voxels contained within parotid gland ROI were deformably registered. Results: Average whole-gland or voxel-by-voxel models incorporating parotid D{sub Met} (defined as the pretreatment parotid SUV weighted by dose) accurately predicted posttreatment changes in parotid FDG uptake (e.g., fractional parotid SUV). Fractional loss of parotid FDG uptake closely paralleled early parotid toxicity defined by posttreatment salivary output (p < 0.01) and Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer xerostomia scores (p < 0.01). Conclusions: In this pilot series, loss of parotid FDG uptake was strongly associated with acute clinical post-RT parotid toxicity. D{sub Met} may potentially be used to guide function-sparing treatment planning. Prospective validation of FDG-PET-CT as a convenient, quantifiable imaging biomarker of parotid function is warranted and ongoing.

  8. Diagnosis and management of xerostomia and hyposalivation

    OpenAIRE

    Villa A; Connell CL; Abati S.

    2014-01-01

    Alessandro Villa,1,2 Christopher L Connell,3 Silvio Abati4 1Division of Oral Medicine and Dentistry, Brigham and Women’s Hospital, Boston, MA, USA; 2Department of Oral Medicine, Infection and Immunity, Harvard School of Dental Medicine, Boston, MA, USA; 3Department of General Dentistry, Boston University Henry M Goldman School of Dental Medicine, Boston, MA, USA; 4Dental Clinic, Department of Health Sciences, University of Milan, Milano, Italy Abstract: Xerostomia, the subjective...

  9. Diagnosis and management of xerostomia and hyposalivation

    OpenAIRE

    Villa, Alessandro,

    2014-01-01

    Alessandro Villa,1,2 Christopher L Connell,3 Silvio Abati4 1Division of Oral Medicine and Dentistry, Brigham and Women’s Hospital, Boston, MA, USA; 2Department of Oral Medicine, Infection and Immunity, Harvard School of Dental Medicine, Boston, MA, USA; 3Department of General Dentistry, Boston University Henry M Goldman School of Dental Medicine, Boston, MA, USA; 4Dental Clinic, Department of Health Sciences, University of Milan, Milano, Italy Abstract: Xerostomia, the su...

  10. Metabolic Imaging Biomarkers of Postradiotherapy Xerostomia

    International Nuclear Information System (INIS)

    Purpose: Xerostomia is a major complication of head and neck radiotherapy (RT). Available xerostomia measures remain flawed. [18F]fluorodeoxyglucose-labeled positron emission tomography-computed tomography (FDG-PET-CT) is routinely used for staging and response assessment of head and neck cancer. We investigated quantitative measurement of parotid gland FDG uptake as a potential biomarker for post-RT xerostomia. Methods and Materials: Ninety-eight locally advanced head and neck cancer patients receiving definitive RT underwent baseline and post-RT FDG-PET-CT on a prospective imaging trial. A separate validation cohort of 14 patients underwent identical imaging while prospectively enrolled in a second trial collecting sialometry and patient-reported outcomes. Radiation dose and pre- and post-RT standard uptake values (SUVs) for all voxels contained within parotid gland ROI were deformably registered. Results: Average whole-gland or voxel-by-voxel models incorporating parotid DMet (defined as the pretreatment parotid SUV weighted by dose) accurately predicted posttreatment changes in parotid FDG uptake (e.g., fractional parotid SUV). Fractional loss of parotid FDG uptake closely paralleled early parotid toxicity defined by posttreatment salivary output (p Met may potentially be used to guide function-sparing treatment planning. Prospective validation of FDG-PET-CT as a convenient, quantifiable imaging biomarker of parotid function is warranted and ongoing.

  11. Diagnosis and management of xerostomia and hyposalivation

    Directory of Open Access Journals (Sweden)

    Villa A

    2014-12-01

    Full Text Available Alessandro Villa,1,2 Christopher L Connell,3 Silvio Abati4 1Division of Oral Medicine and Dentistry, Brigham and Women’s Hospital, Boston, MA, USA; 2Department of Oral Medicine, Infection and Immunity, Harvard School of Dental Medicine, Boston, MA, USA; 3Department of General Dentistry, Boston University Henry M Goldman School of Dental Medicine, Boston, MA, USA; 4Dental Clinic, Department of Health Sciences, University of Milan, Milano, Italy Abstract: Xerostomia, the subjective complaint of dry mouth, and hyposalivation remain a significant burden for many individuals. Diagnosis of xerostomia and salivary gland hypofunction is dependent upon a careful and detailed history and thorough oral examination. There exist many options for treatment and symptom management: salivary stimulants, topical agents, saliva substitutes, and systemic sialogogues. The aim of this review is to investigate the current state of knowledge on management and treatment of patients affected by xerostomia and/or hyposalivation. Keyword: saliva stimulation, dry mouth, saliva substitutes, sialogogues

  12. Radiation-induced chromosomal instability

    Energy Technology Data Exchange (ETDEWEB)

    Ritter, S. [GSI, Biophysics, Darmstadt (Germany)

    1999-03-01

    Recent studies on radiation-induced chromosomal instability in the progeny of exposed mammalian cells were briefly described as well as other related studies. For the analysis of chromosomal damage in clones, cells were seeded directly after exposure in cell well-dish to form single cell clones and post-irradiation chromosome aberrations were scored. Both exposure to isoeffective doses of X-ray or 270 MeV/u C-ions (13 keV/{mu}m) increased the number of clones with abnormal karyotype and the increase was similar for X-ray and for C-ions. Meanwhile, in the progeny of cells for mass cultures, there was no indication of a delayed expression of chromosomal damage up to 40 population doublings after the exposure. A high number of aberrant cells were only observed directly after exposure to 10.7 MeV/u O-ions, i.e. in the first cycle cells and decreased with subsequent cell divisions. The reason for these differences in the radiation-induced chromosomal instability between clonal isolates and mass culture has not been clarified. Recent studies indicated that genomic instability occurs at a high frequency in the progeny of cells irradiated with both sparsely and densely ionizing radiation. Such genomic instability is thought likely to increase the risk of carcinogenesis, but more data are required for a well understanding of the health risks resulting from radiation-induced delayed instability. (M.N.)

  13. Internet information on xerostomia : what should patients expect?

    NARCIS (Netherlands)

    Delli, K.; Livas, C.; Spijkervet, F. K.; Vissink, A.

    2015-01-01

    ObjectiveTo assess the qualitative standards of the information distributed via the Internet regarding xerostomia. Materials and MethodsA comprehensive electronic search was performed for xerostomia' and dry mouth' separately using four search engines. The first 30 results from each search term-engi

  14. A phase II study of Biotene in the treatment of postradiation xerostomia in patients with head and neck cancer.

    Science.gov (United States)

    Warde, P; Kroll, B; O'Sullivan, B; Aslanidis, J; Tew-George, E; Waldron, J; Maxymiw, W; Liu, F F; Payne, D; Cummings, B

    2000-05-01

    %) reported an improvement in oral discomfort, and 12 of these (43%) had a major improvement in their symptoms. The results of this study suggest that the use of Biotene (mouthwash, toothpaste and chewing gum) and Oralbalance gel can improve many of the symptoms of radiation-induced xerostomia. A placebo effect could account for many of the observed improvements in symptoms, and in order to assess the role of these agents in the management of patients with postirradiation xerostomia a randomised phase III study is needed. PMID:10789961

  15. Hubungan Perawatan Kemoterapi Pada Pasien Kanker Dengan Terjadinya Xerostomia di RSUP H. Adam Malik, Medan

    OpenAIRE

    Ilyana binti AB. Rahman

    2011-01-01

    Xerostomia adalah keadaan di mana mulut kering akibat pengurangan atau tiadanya aliran saliva. Banyak faktor yang dapat menyebabkan xerostomia, salah satunya adalah kemoterapi. Tujuan penelitian ini adalah untuk mengetahui prevalensi terjadinya xerostomia pada pasien yang dikemoterapi di RSUP HAM Medan dan untuk mengetahui apakah ada hubungan antara perawatan kemoterapi pada pasien kanker dengan terjadinya xerostomia di RSUP HAM Medan. Penelitian analitik dengan pendekatan c...

  16. Radiation-induced cardiovascular effects

    Science.gov (United States)

    Tapio, Soile

    Recent epidemiological studies indicate that exposure to ionising radiation enhances the risk of cardiovascular mortality and morbidity in a moderate but significant manner. Our goal is to identify molecular mechanisms involved in the pathogenesis of radiation-induced cardiovascular disease using cellular and mouse models. Two radiation targets are studied in detail: the vascular endothelium that plays a pivotal role in the regulation of cardiac function, and the myocardium, in particular damage to the cardiac mitochondria. Ionising radiation causes immediate and persistent alterations in several biological pathways in the endothelium in a dose- and dose-rate dependent manner. High acute and cumulative doses result in rapid, non-transient remodelling of the endothelial cytoskeleton, as well as increased lipid peroxidation and protein oxidation of the heart tissue, independent of whether exposure is local or total body. Proteomic and functional changes are observed in lipid metabolism, glycolysis, mitochondrial function (respiration, ROS production etc.), oxidative stress, cellular adhesion, and cellular structure. The transcriptional regulators Akt and PPAR alpha seem to play a central role in the radiation-response of the endothelium and myocardium, respectively. We have recently started co-operation with GSI in Darmstadt to study the effect of heavy ions on the endothelium. Our research will facilitate the identification of biomarkers associated with adverse cardiac effects of ionising radiation and may lead to the development of countermeasures against radiation-induced cardiac damage.

  17. Radiation-induced leiomyosarcoma of the oropharynx

    Directory of Open Access Journals (Sweden)

    Maier Wolfgang

    2006-08-01

    Full Text Available Abstract Leiomyosarcoma is a malignant mesenchymal tumor originating from smooth muscle cells, which most frequently develops in the myometrium and in the gastro-intestinal tract. Reviewing the international literature, radiation-induced sarcoma arise in 0.035 to 0.2 % of all irradiated patients. Especially in the head and neck region, radiation-induced leiomyosarcoma is an extremely rare lesion. The authors report a case of a radiation-induced leiomyosarcoma of the tonsillar region of the oropharynx in a 51-year-old male patient, who had undergone radiation therapy of this region 38 years before. The lesion was treated by radical surgery. Diagnostic steps, histological presentation and therapy are described in detail and the literature concerning radiation induced malignancies in general as well as radiation induced leiomyosarcoma in particular is reviewed. The highlights of this case are an extremely uncommon location and a rare pathological entity of radiation induced malignancies.

  18. Radiation-induced polymerization of acrylated systems

    International Nuclear Information System (INIS)

    Complete text of publication follows. It has been generally accepted that ionizing radiation induces free radical polymerization in acrylate compounds. It is also reported that, following primary ionization events, acrylates and methacrylates scavenge thermalized electrons to give rise to radical anions and radical cations, which undergo reactions producing the corresponding free radicals. Acrylates have received the most attention in radiation curable pressure sensitive adhesives (PSAs). 2-EHA is well known for its unique pressure-sensitive adhesive properties. An understanding of its primary mechanism of polymerization is of industrial as well as fundamental interest. High entanglement and high molecular weight between crosslinks are crucial for the high shear and peel strength, required of PSAs. Such polymers may be formed using thermal and UV-initiation in solvent or emulsion. Electron beam can also provide these properties when the monomer is polymerized at moderate dose rates and at low temperature. Pulsed electron beam provides a special advantage under conditions where the dose per pulse is below the threshold for overlap (ca. 40 Gy/pulse) and the pulse rate is high enough (>1 kHz) to maintain a quasi-heterogeneous mode at high doses rates. Maintaining low temperature in the early stages of polymerization is important in achieving good properties

  19. Radiation-induced thermoacoustic imaging

    International Nuclear Information System (INIS)

    This invention provides a new technique for obtaining information non-invasively on the composition and structures of a material or body by detecting radiation-induced thermoacoustic image features. This is accomplished by utilizing the acoustic wave generated by sudden thermal stress. The sudden thermal stress is induced by a pulse of radiation which deposits energy causing a rapid, but very small, rise of temperature (typically, ΔT approximately 10sup(-6) - 10sup(-5) deg C). The radiation may be ionizing radiation, such as high energy electrons, photons (x-rays), neutrons, or other charged particles or it may be non-ionizing radiation, such as R.F. and microwave electromagnetic radiation and ultrasonic radiation. The choice of radiation depends on the nature of the body to be imaged and the type of information desired

  20. Drug induced xerostomia in elderly individuals: An institutional study

    Directory of Open Access Journals (Sweden)

    Shishir Ram Shetty

    2012-01-01

    Full Text Available Introduction : With better health care facilities and nutritional levels the average life expectancy of Indian population has been on the rise over the years. Most of the geriatric population is under long-term medication. Aim : The aim of this study was to evaluate the synergistic effect of multiple xerostomia drugs. Materials and Methods : Unstimulated saliva was measured in 60 geriatric patients, and xerostomia questionnaire and quality-of-life scale were also administered. Results : There was a very highly significant reduction in the salivary flow rates of patients under multiple xerostomia-inducing drugs. Conclusion : The synergistic effect of the xerostomia inducing medication could be the possible factor responsible for reduced salivary flow in elderly individuals using such drugs

  1. Hubungan Pasien Penyakit Ginjal Kronis yang Menjalani Hemodialisis dengan Xerostomia

    OpenAIRE

    Sitompul, Ivan Poltak

    2015-01-01

    Penyakit ginjal kronis tahap 5 dapat menyebabkan kondisi uremia, yaitu peningkatan urea dan zat-zat sisa metabolisme di dalam darah. Hal inilah yang dapat menyebabkan berbagai manifestasi pada tubuh, termasuk juga manifestasi di rongga mulut. Salah satu manifestasi di rongga mulut yang paling sering adalah xerostomia. Penelitian ini bertujuan untuk melihat hubungan antara pasien penyakit ginjal kronis yang menjalani hemodialisis dengan xerostomia. Rancangan penelitian ini adalah penelitian an...

  2. Xerostomia Sebagai Salah Satu Efek Samping Terapi Radiasi

    OpenAIRE

    Rini Ekasari

    2008-01-01

    Xerostomia adalah salah satu efek samping dari terapi radiasi terhadap kepala dan leher yang paling umum. Keadaan ini merupakan suatu gejala dan bukan penyakit, yang umumnya berhubungan dengan berkurangnya saliva. Bagi pasien keadaan ini sangat tidak menyenangkan begitu pula bagi dokter gigi merupakan masalah yang menyulitkan. Qleh karena itu, penting bagi dokter gigi sadar akan masalah xerostomia sebagai salah satu efek samping terapi radiasi, sehingga perawatan yang tepat dapat dilakukan un...

  3. Drug induced xerostomia in elderly individuals: An institutional study

    OpenAIRE

    Shishir Ram Shetty; Sunanda Bhowmick; Renita Castelino; Subhas Babu

    2012-01-01

    Introduction : With better health care facilities and nutritional levels the average life expectancy of Indian population has been on the rise over the years. Most of the geriatric population is under long-term medication. Aim : The aim of this study was to evaluate the synergistic effect of multiple xerostomia drugs. Materials and Methods : Unstimulated saliva was measured in 60 geriatric patients, and xerostomia questionnaire and quality-of-life scale were also administered. Results : There...

  4. Radiation induced carcinoma of the middle ear

    International Nuclear Information System (INIS)

    Radiation induced carcinoma of the middle ear is rare. Only four cases have been reported; an additional case is now described. The treatment approach for radiation induced carcinoma of the middle ear has not yet been established. Radiation therapy for advanced cases is discussed as an alternative to surgical treatment. Previous reported cases are reviewed

  5. Open-Label, Long-Term Safety Study of Cevimeline in the Treatment of Postirradiation Xerostomia

    International Nuclear Information System (INIS)

    Purpose: To assess the safety of long-term cevimeline treatment of radiation-induced xerostomia in patients with head-and-neck cancer; and to assess the efficacy of cevimeline in these patients. Methods and Materials: A total of 255 adults with head-and-neck cancer who had received more than 40 Gy of radiation 4 months or more before entry and had clinically significant salivary gland dysfunction received cevimeline hydrochloride 45 mg t.i.d. orally for 52 weeks. Adverse events (AEs), their severity, and their relationship to the study medication were assessed by each investigator. The efficacy assessment was based on subjects' global evaluation of oral dryness on a scale of 0 (none) to 3 (severe). Results: Overall, 175 subjects (68.6%) experienced expected treatment-related AEs, most mild to moderate. The most frequent was increased sweating (47.5%), followed by dyspepsia (9.4%), nausea (8.2%), and diarrhea (6.3%). Fifteen subjects (5.9%) experienced Grade 3 treatment-related AEs, of which the most frequent was increased sweating. Eighteen subjects (7.1%) reported at least one serious AE, and 45 subjects (17.6%) discontinued study medication because of an AE. The global efficacy evaluation at the last study visit showed that cevimeline improved dry mouth in most subjects (59.2%). Significant improvement was seen at each study visit in the mean change from baseline of the numeric global evaluation score (p < 0.0001). Conclusions: Cevimeline 45 mg t.i.d. was generally well tolerated over a period of 52 weeks in subjects with xerostomia secondary to radiotherapy for cancer in the head-and-neck region

  6. Cellular basis of radiation-induced fibrosis

    International Nuclear Information System (INIS)

    Fibrosis is a common sequela of both cancer treatment by radiotherapy and accidental irradiation and has been described in many tissues including skin, lung, heart and liver. The underlying mechanisms of the radiation-induced fibrosis still remain to be resolved. In the present review we tried to illustrate the basic cellular mechanisms of radiation-induced fibrosis based on the newest findings arising from molecular radiobiology and cell biology. Based on these findings the cellular mechanism of radiation-induced fibrosis can be seen as a multicellular process involving various interacting cell systems in the target organ resulting in the fibrotic phenotype of the fibroblast/fibrocyte cell system

  7. An Evidence-Based Review Literature About Risk Indicators and Management of Unknown-Origin Xerostomia

    OpenAIRE

    Farzaneh Agha-hosseini; Mahdieh-Sadat Moosavi

    2013-01-01

    Objective: This evidence-based article reviews risk indicators and management of unknown-origin xerostomia. Xerostomia and hyposalivation refer to different aspects of dry mouth. Xerostomia is a subjective sensation of dry mouth, whilst hyposalivation is defined as an objective assessment of reduced salivary flow rate. About 30% of the elderly (65 years and older) experience xerostomia and hyposalivation. Structural and functional factors, or both may lead to salivary gland dysfunction.Study ...

  8. Xerostomia after radiotherapy in the head and neck area: Long-term observations

    International Nuclear Information System (INIS)

    To investigate the development of xerostomia more than 5 years after radiotherapy for head and neck cancer, a prospective longitudinal study was done. A xerostomia questionnaire was answered by 42 patients 41 and 90 months after radiotherapy: xerostomia at rest did not change significantly over time whereas the difficulties with speaking improved and the difficulties with eating worsened. Subjective xerostomia does not reach a steady state even more than 5 years after radiotherapy.

  9. Biotechnological advances in neuro-electro-stimulation for the treatment of hyposalivation and xerostomia

    OpenAIRE

    Lafaurie, G.; Fedele, S.; Lopez, R. M. G.; Wolff, A.; Strietzel, F.; Porter, S. R.; Konttinen, Y T

    2009-01-01

    Treatment of xerostomia is a common clinical challenge in the oral medicine practice. Although some treatments have been used to improve the symptoms of xerostomia, none is completely satisfactory for the patients who suffer of this alteration. In the last years non-pharmacological treatments based on electro-stimulation for the treatment of xerostomia have been developed. This review is aimed at presenting new developments for the treatment of xerostomia, applying neuro-electro-stimulation b...

  10. Mastication and swallowing in patients with postirradiation xerostomia

    International Nuclear Information System (INIS)

    Purpose: Very little objective data has been reported on mastication and swallowing in xerostomic patients, which would substantiate presumed causal relationships between xerostomia and patient complaints. The purpose was to elucidate which components of mastication and swallowing were abnormal, and most directly related to xerostomia, and which appeared unaffected. Methods and Materials: A retrospective analysis of timing events in mastication and swallowing was done using videofluoroscopic data for 15 cancer patients with xerostomia, and 20 normal controls. Scintigraphy was also used to determine oropharyngeal residue after a water swallow. Cancer treatment modalities included radiation therapy or chemoradiation therapy. Results: For barium liquid and paste substances, timing measures were equivalent for controls and patients. Xerostomic patients took 46% longer to masticate a shortbread cookie, and timing for the initiation of swallowing was shorter, but duration of swallowing appeared unaffected. Oral and pharyngeal residues following the swallow were greater in the patient group. Conclusions: Xerostomia primarily affected mastication and oral manipulation of a dry, absorbent food material. Increased oral and pharyngeal residues after a water swallow are ambiguously related to xerostomia. The initiation and duration of the pharyngeal swallow was not abnormal

  11. Radiation-induced carcinoma of the penis

    International Nuclear Information System (INIS)

    Two patients with carcinoma of the penis were treated with interstitial radiation. They were cured of their disease for 17 and 21 years respectively and then developed radiation-induced tumours. (author)

  12. Radiation-induced cataract-genesis: pathophysiologic, radiobiological and clinical aspects

    International Nuclear Information System (INIS)

    Cataract-genesis is a widely reported late effect of irradiated crystalline lens. In this review the authors discussed the different aspects of radiation cataract pathogenesis, and the different mechanisms involved in the lens opacification, particularly the epithelium modifications such as epithelial cell death. The authors also reported the influence of radiation exposure on cataract formation following total body irradiation TBI) and autologous or allogeneic bone marrow transplantation for hematologic malignancies. Moreover, the radiobiological parameters are not studied for the crystalline lens of human. We applied for the first time the linear quadratic (LQ) and biological effective dose (BED) concept to TBI data. The calculated value of α/β of 1 Gy is in the range of the values reported for the other late responding tissues. The other risk factors for cataract development after TBI such as age, gender, central nervous system boost, long-term steroid therapy and heparin administration are discussed. In terms of cataract or sicca syndrome prevention, numerous compounds have been successfully tested in experimental models or used for the prevention of radiation-induced xerostomia in patients treated for head and neck cancer. However, none of them has been clinically evaluated for ocular radiation late effects prevention. In this report the authors discussed some of the radioprotectors potentially interesting for radiation-induced cataract or sicca syndrome prevention. (author)

  13. Chronic xerostomia increases esophageal acid exposure and is associated with esophageal injury

    International Nuclear Information System (INIS)

    OBJECTIVES: To assess the effects of chronic xerostomia on parameters of gastroesophageal reflux and esophagitis. DESIGN: Observational study of a cohort of male patients with xerostomia and age-matched control subjects. SETTING: Tertiary-care Veterans Affairs Medical Center. SUBJECTS: Sixteen male patients with chronic xerostomia secondary to radiation for head and neck cancers or medications. Nineteen age-matched male control subjects with comparable alcohol and smoking histories. MEASUREMENTS AND MAIN RESULTS: Esophageal motility was similar in patients with xerostomia and controls. Clearance of acid from the esophagus and 24-hour intraesophageal pH were markedly abnormal in patients with xerostomia. Symptoms and signs of esophagitis were significantly more frequent in subjects with xerostomia. CONCLUSIONS: Chronic xerostomia may predispose to esophageal injury, at least in part, by decreasing the clearance of acid from the esophagus and altering 24-hour intraesophageal pH. Esophageal injury is a previously unreported complication of long-term salivary deficiency

  14. Hazard of the radiation induced thyroid cancer

    International Nuclear Information System (INIS)

    The level of thyroid cancer in Belarus before Chernobyl accident was low and made in different age and sex groups 0,03-2,5 (male) and 0,1-3,9 (female) per 100000 correspondingly. Different risk factors, which can influence the thyroid cancer development, are being taken into account. They are the factors of environment (strong external irradiation, long-time irradiation for medical purposes or in result of disaster), endo gen factors (hormonal, reproductive, genetic predisposition), some medicinal preparations and other. The protective effect of vegetable and fish consumption was found out. Among the factors of thyroid cancer development one of the most important is radiation. There is a point of view, which assumes that one of the reasons of thyroid cancer cases increase among the population of developed countries is increase of radiation induced thyroid cancer. The results of first research testify the influence of radiation factor on thyroid cancer development. During the period 1920 -1960 in the USA X-ray therapy was applied for the treatment of different good-quality diseases. Thyroid got in the zone of irradiation during the complex treatment with using of radiation. The results of the research of 1970 revealed that 70% of children with thyroid cancer were exposed to radiation in children's age. The subsequent researches of by-effects from the side of a thyroid at beam therapy of various diseases alongside with the results of the estimation of consequences of inhabitants of Hiroshima and Nagasaki irradiation owing to nuclear bombardment have shown the influence of irradiation of a thyroid on cancer development. High quantity of radio-epidemiological researches was directed to the studying of the consequences of thyroid external irradiation at young age. In all carried out researches the quantity of observed thyroid cancer cases among irradiated people has exceeded number of expected. The influence of thyroid internal irradiation by I-131 at young age was

  15. Dry Eye Disease Patients with Xerostomia Report Higher Symptom Load and Have Poorer Meibum Expressibility.

    Science.gov (United States)

    Fostad, Ida G; Eidet, Jon R; Utheim, Tor P; Ræder, Sten; Lagali, Neil S; Messelt, Edvard B; Dartt, Darlene A

    2016-01-01

    The purpose of the study was to investigate if xerostomia (dry mouth) is associated with symptoms and signs of dry eye disease (DED). At the Norwegian Dry Eye Clinic, patients with symptomatic DED with different etiologies were consecutively included in the study. The patients underwent a comprehensive ophthalmological work-up and completed self-questionnaires on symptoms of ocular dryness (Ocular Surface Disease Index [OSDI] and McMonnies Dry Eye Questionnaire) and the Sjögren's syndrome (SS) questionnaire (SSQ). Three hundred and eighteen patients (52% women and 48% men) with DED were included. Patient demographics were: 0 to 19 years (1%), 20 to 39 (25%), 40 to 59 (34%), 60 to 79 (35%) and 80 to 99 (5%). Xerostomia, defined as "daily symptoms of dry mouth the last three months" (as presented in SSQ) was reported by 23% of the patients. Female sex was more common among patients with xerostomia (81%) than among non-xerostomia patients (44%; P<0.001). Patients with xerostomia (60 ± 15 years) were older than those without xerostomia (51 ± 17; P<0.001). The use of prescription drugs was more prevalent among xerostomia patients (65%) than among non-xerostomia patients (35%; P<0.021; adjusted for age and sex). Patients with xerostomia had a higher OSDI score (19.0 ± 10.0) than those without xerostomia (12.9 ± 8.0; P<0.001). Moreover, xerostomia patients had more pathological meibum expressibility (0.9 ± 0.7) than those without xerostomia (0.7 ± 0.8; P = 0.046). Comparisons of OSDI and ocular signs were performed after controlling for the effects of sex, age and the number of systemic prescription drugs used. In conclusion, xerostomia patients demonstrated a higher DED symptom load and had poorer meibum expressibility than non-xerostomia patients. PMID:27148875

  16. Xerostomia, Hyposalivation, and Salivary Flow in Diabetes Patients

    Science.gov (United States)

    Casañas, Elisabeth; Ramírez, Lucía; de Arriba, Lorenzo; Hernández, Gonzalo

    2016-01-01

    The presence of xerostomia and hyposalivation is frequent among diabetes mellitus (DM) patients. It is not clear if the presence of xerostomia and hyposalivation is greater in DM than non-DM patients. The aims of this systematic review are (1) to compare the prevalence rates of xerostomia, (2) to evaluate the salivary flow rate, and (3) to compare the prevalence rates of hyposalivation in DM versus non-DM population. This systematic review was conducted according to the PRISMA group guidelines by performing systematic literature searches in biomedical databases from 1970 until January 18th, 2016. All studies showed higher prevalence of xerostomia in DM patients in relation to non-DM population, 12.5%–53.5% versus 0–30%. Studies that analyzed the quantity of saliva in DM population in relation to non-DM patients reported higher flow rates in non-DM than in DM patients. The variation flow rate among different studies in each group (DM/CG) is very large. Only one existing study showed higher hyposalivation prevalence in DM than non-DM patients (45% versus 2.5%). In addition, quality assessment showed the low quality of the existing studies. We recommend new studies that use more precise and current definitions concerning the determination and diagnosis of DM patients and salivary flow collection.

  17. Radiation-induced carotid artery disease

    International Nuclear Information System (INIS)

    Nine patients with atherosclerotic carotid artery disease associated with neck radiation were compared to 40 control patients. The data suggest that significant differences in age, incidence of coronary and peripheral vascular disease, elevated lipids and serum cholesterol, and the angiographic incidence of disseminated atherosclerosis justify the description of radiation-induced carotid disease as a clinical entity. Elevated serum cholesterol and hyperlipidemia may contribute to the development of radiation-induced vascular disease. Successful surgical reconstruction does not appear to be influenced by the prior radiotherapy, although periarterial fibrosis and increased difficulty in separating the plaques from the vascular media was encountered

  18. Some radiation-induced effects in typical calorimetric materials and sensors

    International Nuclear Information System (INIS)

    The radiation-induced effects of the electron beams (EB) generated by accelerators in typical calorimetric materials and sensors have been surveyed and investigated. These effects influence the useful lifetime of the materials and sensors at high doses of about 4,000 to 5,000 kGy. (author)

  19. Improvement in Xerostomia Related Quality of Life of Oral Cavity and Oropharyngeal Squamous Cell Carcinoma Patients Treated with IMRT Compared to Conventional RT

    OpenAIRE

    Aseem Rai Bhatnagar; Rameshwaram Sharma; Prashant Kumbhaj

    2013-01-01

    BACKGROUND: The incidence of head and neck squamous cell cancer is quite high in India as compared to the developed countries. Conventional RT for the majority of head and neck cancers is delivered using two parallel opposed radiation beams and parotid glands receive a significant radiation dose (>50 Gy) resulting in permanent xerostomia. MATERIALS AND METHODS: For this study, we evaluated 64 patients with oral cavity and oropharyngeal squamous cell carcinomas, treated by IMRT / Conventio...

  20. The Treatment Outcome and Radiation-Induced Toxicity for Patients with Head and Neck Carcinoma in the IMRT Era: A Systematic Review with Dosimetric and Clinical Parameters

    Directory of Open Access Journals (Sweden)

    Vassilis Kouloulias

    2013-01-01

    Full Text Available A descriptive analysis was made in terms of the related radiation induced acute and late mucositis and xerostomia along with survival and tumor control rates (significance level at 0.016, bonferroni correction, for irradiation in head and neck carcinomas with either 2D Radiation Therapy (2DRT and 3D conformal (3DCRT or Intensity Modulated Radiation Therapy (IMRT. The mean score of grade > II xerostomia for IMRT versus 2-3D RT was 0.31 ± 0.23 and 0.56 ± 0.23, respectively (Mann Whitney, P<0.001. The parotid-dose for IMRT versus 2-3D RT was 29.56 ± 5.45 and 50.73 ± 6.79, respectively (Mann Whitney, P=0.016. The reported mean parotid-gland doses were significantly correlated with late xerostomia (spearman test, rho = 0.5013, P<0.001. A trend was noted for the superiority of IMRT concerning the acute oral mucositis. The 3-year overall survival for either IMRT or 2-3DRT was 89.5% and 82.7%, respectively (P=0.026, Kruskal-Wallis test. The mean 3-year locoregional control rate was 83.6% (range: 70–97% and 74.4 (range: 61–82%, respectively (P=0.025, Kruskal-Wallis. In conclusion, no significant differences in terms of locoregional control, overall survival and acute mucositis could be noted, while late xerostomia is definitely higher in 2-3D RT versus IMRT. Patients with head and neck carcinoma should be referred preferably to IMRT techniques.

  1. The Split Denture: Managing Xerostomia in Denture Patients: A Case Report

    OpenAIRE

    Dabas, Nupur; Phukela, Sumit Singh; Yadav, Harish

    2011-01-01

    Wearing complete dentures can be an extremely uncomfortable experience for the people with Xerostomia. Various treatment modalities have been suggested in the literature to overcome the problem of xerostomia in complete denture patients. Incorporating reservoirs containing salivary substitutes, into dentures, is one of these treatment modalities. This paper presents case report of a patient suffering from xerostomia who was successfully treated with a new form of reservoir dentures. This new ...

  2. Xerostomia Due to Systemic Disease: A Review of 20 Conditions and Mechanisms

    OpenAIRE

    Mortazavi, H; Baharvand, M.; Movahhedian, A; M Mohammadi; A. Khodadoustan

    2014-01-01

    Xerostomia is a common complaint of nearly half of the elderly population and about one-fifth of younger adults. It causes several signs and symptoms, and compromise oral functions and health-related quality-of-life. Multiple reasons are proposed to describe the etiology of xerostomia such as local factors, psychogenic factors, and systemic diseases. In order to manage xerostomia effectively, identification of the main causality is mandatory. The aim of this review was to present systemic dis...

  3. Hubungan Penggunaan Obat Antidepresan Terhadap Terjadinya Xerostomia di RSUD Ahmad Mochtar Bukittinggi

    OpenAIRE

    Anggarini, Vanazia Rizka

    2010-01-01

    Xerostomia didefinisikan sebagai keluhan subjektif dari mulut kering yang disebabkan oleh penurunan produksi saliva. Banyak faktor yang dapat menyebabkan xerostomia, salah satunya adalah obat-obatan. Tujuan penelitian ini adalah untuk mengetahui prevalensi terjadinya xerostomia pada pasien yang menggunakan obat antidepresan pada pasien poli psikiatri RSUD Dr. Ahmad Mochtar Bukittinggi dan untuk mengetahui apakah ada hubungan antara penggunaan obat antidepresan pada pasien poli psikiatri RSUD ...

  4. Efficacy of Pilocarpine and Bromhexine in Improving Radiotherapy-induced Xerostomia

    OpenAIRE

    2013-01-01

    Background and aims. Xerostomia is one of the most common complications of head and neck radiotherapy. The aim of this study was to evaluate and compare the efficacy of pilocarpine and bromhexine in improving radiotherapy-induced xerostomia and its associated symptoms. Materials and methods. In this single-blind, randomized crossover study, pilocarpine and bromhexine tablets were used by twenty-five patients suffered from xerostomia, with a medical history of head and neck radiotherapy. At st...

  5. Xerostomia in geriatric patients: a burgeoning global concern.

    Science.gov (United States)

    Anil, Sukumaran; Vellappally, Sajith; Hashem, Mohamed; Preethanath, Reghunathan S; Patil, Shankargouda; Samaranayake, Lakshman P

    2016-02-01

    Saliva plays a key role in maintaining oral homeostasis, function, and health. The prevalence of xerostomia and its consequences are rising due to the increasing aging population, the effects of some systemic diseases, medical management, and commonly-prescribed medications that reduce saliva production. When salivary function is diminished, patients are at a greater risk of developing caries, discomfort in wearing dentures, and opportunistic diseases, such as candidiasis. The psychosocial aspects of xerostomia can range from a mild effect on self-rated oral health to frustration, embarrassment, unhappiness, or substantial disruptions in quality of life. This article reviews the clinical features, diagnosis, and prevalence of dry mouth, as well as its treatment strategies. PMID:25175324

  6. Study on radiation-induced reaction in microscopic region for basic understanding of electron beam patterning in lithographic process. 2. Relation between resist space resolution and space distribution of ionic species

    International Nuclear Information System (INIS)

    For basic research on electron beam lithography, the time-dependent distribution was measured. In the case of nano-scale electron beam lithography, the distribution of ionic species is thought to have an influence on the space resolution or the line edge roughness. As a model compound of a resist resin, liquid n-dodecane was used as a sample. The experiment was carried out using the subpicosecond pulse radiolysis. The experimental data was analyzed by Monte Carlo simulation based on the diffusion in an electric field. The simulation data were convoluted by the response function and fitted to the experimental data. By transforming the time-dependent behavior of cation radicals to the distribution function of cation radical-electron distance, the time-dependent distribution was obtained. Subsequently, the relation between the space resolution and the space distribution of ionic species was discussed. (author)

  7. A Clinical Evaluation Denture Adhesives Used by Patients With Xerostomia

    OpenAIRE

    Bogucki, Zdzislaw A.; Napadlek, Piotr; Dabrowa, Tomasz

    2015-01-01

    Abstract The purpose of study was to analyze the participants’ opinions concerning the effectiveness of 6 denture adhesives (DA). The study group included 60 participants. Criteria for selecting the patients were as follows: reduced retention and stabilization of maxillary complete dentures and xerostomia. These features were evaluated on basis of clinical examination and standard sialometry tests (u-SFR). Retention of maxillary dentures was scored by modified Kapur index before application o...

  8. Xerostomia Sebagai Akibat Terapi Radiasi Pada Penderita Kanker Tiroid

    OpenAIRE

    Nasution, Salviah Aisyah

    2008-01-01

    Pada saat ini terapi radiasi telah meningkat frekuensi pemakaiannya sebagai suatu bentuk perawatan dalam menanggulangi penyakit-penyakit kanker kepala dan leher. Sayangnya, terapi ini memiliki efek samping/akibat yang tidak diinginkan. Oleh karena itu, penting bagi dokter gigi sadar akan masalah xerostomia sebagai salah satu efek samping yang sering terjadi setelah terapi radiasi kepala dan leher sehingga perawatan yang tepat dapat dilakukan untuk meminimalkan terjadinya komplikasi akibat rad...

  9. Hubungan Obat-obatan Antihipertensi Terhadap Terjadinya Xerostomia

    OpenAIRE

    Marlisa

    2011-01-01

    Hipertensi merupakan salah satu penyebab paling penting dari kematian dini karena erat kaitannya dengan resiko penyakit kardiovaskuler dan ditandai dengan tekanan darah sistoliknya lebih tinggi atau sama dengan 140 mm Hg serta tekanan darah diastoliknya lebih tinggi atau sama dengan 90 mm Hg. Antihipertensi adalah obat – obatan yang digunakan untuk mengobati hipertensi. Akan tetapi, obat – obatan tersebut memiliki efek samping sistemik maupun rongga mulut yang salah satunya adalah xerostomia...

  10. High-LET radiation-induce malignant and benign tumors in rat skin

    Energy Technology Data Exchange (ETDEWEB)

    Burns, F.J. [Institute of Environmental Medicine, New York University Medical Center, New York, NY (United States); Zhao, P.; Hiz, Z.; Chen, S.; Roy, N.

    1999-03-01

    In the multistage theory of carcinogenesis, cells progress to cancer through a series of mutations in cancer-relevant genes, and sometimes the intermediate stages become benign neoplastic lesions. Although cancer induction by low LET radiation is subject to repair or recovery in the sense that multiple exposures produce fewer cancers than the same single dose, this recovery is not seen following exposure to high LET radiation. Data are presented on squamous and basal cell carcinoma and fibroma induction in rat skin exposed to: 1. an electron beam (LET=0.34 kV/{mu}), 2. a neon ion beam (LET=30 kV/{mu} ) and 3. an argon ion beam (LET=125 kV/{mu}). Cancer yields were fitted by a LET-dependent quadratic equation, and equation parameters were estimated by regression analysis for each type of radiation. The results are consistent with the interpretation that carcinoma induction can be explained by a pathway involving 2 radiation-induced events, 1 radiation-induced mutation and 1 spontaneous mutation, while benign fibromas can be explained by a pathway involving 1 radiation-induced event and 1 radiation-induced mutation. (author)

  11. A case of xerostomia caused by exposure to radioactive iodine

    International Nuclear Information System (INIS)

    Oral radioiodine (131I) therapy is known to be an effective treatment for differentiated thyroid carcinoma, but it can cause salivary gland impairment. We report a case of xerostomia caused by oral radioiodine therapy for thyroid cancer. A 47-year-old woman consulted our hospital because of tongue pain accompanied by xerostomia. The patient had a history of receiving radioiodine therapy for metastatic thyroid carcinoma 3 times (total 9,990 MBq). Clinical examination demonstrated oral dryness and reduced salivary gland function. On the gum test, the salivary flow was 2 ml in 6 minutes. It was hard to continue chewing for more than 6 minutes because of irritation. A computed tomographic scan showed atrophic changes of both parotid glands. On radioiodine whole-body imaging, uptake of radioiodine was evident in both the parotid and submandibular glands. Based on these findings, xerostomia caused by salivary gland injury due to radioiodine therapy was clinically diagnosed. The salivary gland injury was irreversible, and the patient received symptomatic therapy and pilocarpine hydrochoride. Early intervention to avoid salivary gland injury is important in patients who receive radioactive iodine therapy. (author)

  12. Bile acids in radiation-induced diarrhea

    International Nuclear Information System (INIS)

    Radiation-induced bowel disease manifested by debilitating diarrhea is an unfortunate consequence of therapeutic irradiation for pelvic malignancies. Although the mechanism for this diarrhea is not well understood, many believe it is the result of damage to small bowel mucosa and subsequent bile acid malabsorption. Excess amounts of bile acids, especially the dihydroxy components, are known to induce water and electrolyte secretion and increase bowel motility. We have directly measured individual and total bile acids in the stool samples of 11 patients with radiation-induced diarrhea and have found bile acids elevated two to six times normal in eight of them. Our patients with diarrhea and increased bile acids in their stools had prompt improvement when given cholestyramine. They had fewer stools and returned to a more normal life-style

  13. Study of chemical and radiation induced carcinogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Chmura, A.

    1995-11-01

    The study of chemical and radiation induced carcinogenesis has up to now based many of its results on the detection of genetic aberrations using the fluorescent in situ hybridization (FISH) technique. FISH is time consuming and this tends to hinder its use for looking at large numbers of samples. We are currently developing new technological advances which will increase the speed, clarity and functionality of the FISH technique. These advances include multi-labeled probes, amplification techniques, and separation techniques.

  14. Radiation induced fracture of the scapula

    Energy Technology Data Exchange (ETDEWEB)

    Riggs, J.H. III; Schultz, G.D.; Hanes, S.A. (Los Angeles College of Chiropractic, Whittier, CA (USA))

    1990-10-01

    A case of radiation induced osteonecrosis resulting in a fracture of the scapula in a 76-yr-old female patient with a history of breast carcinoma is presented. Diagnostic imaging, laboratory recommendations and clinical findings are discussed along with an algorithm for the safe management of patients with a history of cancer and musculoskeletal complaints. This case demonstrates the necessity of a thorough investigation of musculoskeletal complaints in patients with previous bone-seeking carcinomas.

  15. Radiation induced fracture of the scapula

    International Nuclear Information System (INIS)

    A case of radiation induced osteonecrosis resulting in a fracture of the scapula in a 76-yr-old female patient with a history of breast carcinoma is presented. Diagnostic imaging, laboratory recommendations and clinical findings are discussed along with an algorithm for the safe management of patients with a history of cancer and musculoskeletal complaints. This case demonstrates the necessity of a thorough investigation of musculoskeletal complaints in patients with previous bone-seeking carcinomas

  16. Radiatively induced Quark and Lepton Mass Model

    CERN Document Server

    Nomura, Takaaki

    2016-01-01

    We propose a radiatively induced quark and lepton mass model in the first and second generation with extra $U(1)$ gauge symmetry and vector-like fermions. Then we analyze the allowed regions which simultaneously satisfy the FCNCs for the quark sector, LFVs including $\\mu-e$ conversion, the quark mass and mixing, and the lepton mass and mixing. Also we estimate the typical value for the $(g-2)_\\mu$ in our model.

  17. Radiation-induced brachial plexopathy: MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Wouter van Es, H. [Department of Radiology, University Hospital Utrecht, Heidelberglaan 100, 3584 CX Utrecht (Netherlands); Engelen, A.M. [Department of Radiation Therapy, University Hospital Utrecht, Utrecht (Netherlands); Witkamp, T.D. [Department of Radiology, University Hospital Utrecht, Heidelberglaan 100, 3584 CX Utrecht (Netherlands); Ramos, L.M.P. [Department of Radiology, University Hospital Utrecht, Heidelberglaan 100, 3584 CX Utrecht (Netherlands); Feldberg, M.A.M. [Department of Radiology, University Hospital Utrecht, Heidelberglaan 100, 3584 CX Utrecht (Netherlands)

    1997-05-01

    Objective. To describe the MR imaging appearance of radiation-induced brachial plexopathy. Design. MR imaging was performed in two patients with the clinical diagnosis of radiation-induced brachial plexopathy and in one with surgically proven radiation fibrosis of the brachial plexus. Patients. Three patients who had had radiation therapy to the axilla and supraclavicular region (two with breast carcinoma and one with Hodgkin`s lymphoma) presented with symptoms in the arm and hand. To exclude metastases or tumor recurrence MR imaging was performed. Results and conclusion. In one patient, fibrosis showing low signal intensity was found, while in two patients high signal intensity fibrosis surrounding the brachial plexus was found on the T2-weighted images. In one case gadolinium enhancement of the fibrosis was seen 21 years after radiation therapy. It is concluded that radiation-induced brachial plexopathy can have different MR imaging appearances. We found that radiation fibrosis can have both low or high signal intensities on T2-weighted images, and that fibrosis can enhance even 21 years after radiation therapy. (orig.). With 3 figs.

  18. A case of radiation-induced glioma

    International Nuclear Information System (INIS)

    A case of malignant cerebellar glioma developing 25 years after radiotherapy for pineal tumor is described. The patient is a 40-year-old male, who was admitted to our department with complaints of dizziness and gait disturbance. neurological examinations revealed symptoms involving the left cerebellar hemisphere and cerebellar vermis. CT scan and MRI demonstrated a circularly enhanced tumor which was located in the left cerebellar hemisphere extending to the vermis. The tumor was diagnosed as malignant glioma. In view of the former radiotherapy, this glioma was suspected to have been induced by radiation. The situation conformed to Walker's criteria for radiation-induced tumor. With the patient under general anesthesia, the tumor was subtotally removed by means of suboccipitel craniectomy. Histopathologically, the tumor was diagnosed as astrocytoma, grade 3. Most radiation-induced gliomas are malignant. There seems to be no significant correlation between the radiation dose; the latent period widely varies, ranging from several years to more than 20 years. Even if the radiation dose is small, there still exists the risk that radiation might induce a tumor. It was concluded that the possibility of radiation-induced tumor should be kept in mind whenever radiation therapy is carried out for brain tumors. (author)

  19. The diagnostic suitability of a xerostomia questionnaire and the association between xerostomia, hyposalivation and medication use in a group of nursing home residents

    OpenAIRE

    van der Putten, Gert-Jan; Brand, Henk S; Schols, Jos M. G. A.; de Baat, Cees

    2010-01-01

    The study objective was to explore the diagnostic suitability of the Xerostomia Inventory and the association between xerostomia, hyposalivation and medication use in a group of nursing home residents. A cross-sectional study was carried out in 50 physically impaired nursing home residents (20 men) with a mean age of 78.1 years (range, 53–98) in The Netherlands. The Xerostomia Inventory-Dutch version was completed for all residents and the data were subjected to exploratory factor analysis to...

  20. Radiation-induced gene expression in human subcutaneous fibroblasts is predictive of radiation-induced fibrosis

    DEFF Research Database (Denmark)

    Rødningen, Olaug Kristin; Børresen-Dale, Anne-Lise; Alsner, Jan;

    2008-01-01

    BACKGROUND AND PURPOSE: Breast cancer patients show a large variation in normal tissue reactions after ionizing radiation (IR) therapy. One of the most common long-term adverse effects of ionizing radiotherapy is radiation-induced fibrosis (RIF), and several attempts have been made over the last...... years to develop predictive assays for RIF. Our aim was to identify basal and radiation-induced transcriptional profiles in fibroblasts from breast cancer patients that might be related to the individual risk of RIF in these patients. MATERIALS AND METHODS: Fibroblast cell lines from 31 individuals with......-treated fibroblasts. Transcriptional differences in basal and radiation-induced gene expression profiles were investigated using 15K cDNA microarrays, and results analyzed by both SAM and PAM. RESULTS: Sixty differentially expressed genes were identified by applying SAM on 10 patients with the highest risk of RIF and...

  1. Hubungan Menopause dengan Terjadinya Xerostomia pada Anggota Perwiritan Nurul Ihsan Kelurahan Payaroba Kecamatan Binjai Barat

    OpenAIRE

    Lubis, Zoraida Sari

    2011-01-01

    Saliva berfungsi menjaga rongga mulut tetap basah dan membantu dalam pengunyahan, penelanan, pencernaan, bicara, dan netralisasi immunologik. Jika fungsi saliva terganggu dan menyebabkan mulut kering, keadaan itu disebut xerostomia. Xerostomia merupakan keluhan subjektif berupa kekeringan di dalam mulut yang ditandai dengan menurunnya jumlah aliran saliva dari normal akibat penurunan produksi saliva dari kedua kelenjar mayor dan minor. Manifestasi berkurangnya aliran saliva dapat ringan, tanp...

  2. Salivary gland dysfunction and xerostomia in Sjögren's syndrome

    DEFF Research Database (Denmark)

    Jensen, Siri Beier; Vissink, Arjan

    2014-01-01

    In this article, salivary gland dysfunction and xerostomia in Sjögren's syndrome (SS) are discussed, with a focus on the pathophysiology of salivary dysfunction in SS, the clinical presentation of dry mouth in SS, how to assess salivary gland hypofunction and xerostomia in SS, and the impact of...

  3. Severity and impact of xerostomia in patients treated with botulinum toxin type b for cervical dystonia: Observations on the quality of life of patients with xerostomia

    OpenAIRE

    Hogan, Patrick; Charles, P. David; Wooten Watts, Maureen; Massey, Janice M.; Miller, Tamara; Mackowiack, John

    2004-01-01

    Background: Although dry mouth (xerostomia) has been reported with botulinum toxin type B used as treatment for cervical dystonia, the impact of this adverse effect (AE) on patients' activities of daily living (ADLs) has not been assessed.

  4. Radiation-induced sensitisation of stainless steels

    International Nuclear Information System (INIS)

    The book contains the proceedings of a symposium on radiation-induced sensitization of stainless steels, which took place at Berkeley, United Kingdom, 1986. The purpose of the symposium was to examine the mechanism leading to inter-granular corrosion of 20%Cr/25% Ni/Nb stainless steel cladding of AGR fuel following irradiation. Nine papers are presented, of which three are theoretical, two papers are based upon corrosion studies of 20%Cr/25%Ni/Nb steel, and the remaining are concerned with compositional redistribution and its measurement. (U.K.)

  5. Acupuncture for pilocarpine-resistant xerostomia following radiotherapy for head and neck malignancies

    International Nuclear Information System (INIS)

    Objective: Xerostomia is a frequent and potentially debilitating toxicity of radiotherapy (XRT) for cancers of the head and neck. This report describes the use of acupuncture as palliation for such patients. Methods and Materials: Eighteen patients with xerostomia refractory to pilocarpine therapy after XRT for head and neck malignancy were offered acupuncture as palliation. All patients are without evidence of cancer recurrence at the primary site. Acupuncture was provided to three auricular points and one digital point bilaterally, with electrostimulation used variably. The Xerostomia Inventory (XI) was administered retrospectively to provide an objective measure of efficacy. Results: Acupuncture contributed to relief from xerostomia to varying degrees. Palliative effect as measured by the XI varied from nil to robust (pre- minus post- therapy values of over 20 points). Nine patients had benefit of over 10 points on the XI. Conclusions: Acupuncture reduces xerostomia in some patients who are otherwise refractory to best current management

  6. The Groningen Radiotherapy-Induced Xerostomia questionnaire: Development and validation of a new questionnaire

    International Nuclear Information System (INIS)

    Purpose: The purpose of this study was to develop and validate a questionnaire (Groningen Radiotherapy-Induced Xerostomia (GRIX) questionnaire) that has the ability to distinguish between patient-rated xerostomia during day and night and can be used to evaluate the impact of emerging radiation delivery techniques aiming at prevention of xerostomia in more detail. Materials and methods: All questions in the GRIX were generated from an exhaustive list of relevant questions according to xerostomia as reported in the literature and reported by patients and health care providers. Finally the GRIX was reduced from 56 questions to a 14-item questionnaire, with four subscales; xerostomia during day and night and sticky saliva during day and night. 315 patients filled out 2936 questionnaires and the GRIX was evaluated by calculating Crohnbach's α for all subscales. Criterion validity was evaluated to compare the GRIX with patient-rated xerostomia scored with the EORTC QLQ-HN35 and physician-rated xerostomia, test-retest analysis and responsiveness were also tested. Results: Crohnbach's α varied for all subscales between 0.88 and 0.94. The GRIX scored well for criterion-related validity on all subscales with high correlations with the EORTC QLQ-HN35 xerostomia and sticky saliva scale as well with physician-rated toxicity scoring. No significant differences were found between test and retest score and the GRIX showed good responsiveness with different time points for all subscales. Conclusion: The GRIX is a validated questionnaire which can be used in future research focusing on patient-rated xerostomia and sticky saliva during day and night in relation with the impact of emerging radiation delivery techniques aiming at reduction of xerostomia.

  7. Dry Eye Disease Patients with Xerostomia Report Higher Symptom Load and Have Poorer Meibum Expressibility

    Science.gov (United States)

    Eidet, Jon R.; Utheim, Tor P.; Ræder, Sten; Lagali, Neil S.; Messelt, Edvard B.; Dartt, Darlene A.

    2016-01-01

    The purpose of the study was to investigate if xerostomia (dry mouth) is associated with symptoms and signs of dry eye disease (DED). At the Norwegian Dry Eye Clinic, patients with symptomatic DED with different etiologies were consecutively included in the study. The patients underwent a comprehensive ophthalmological work-up and completed self-questionnaires on symptoms of ocular dryness (Ocular Surface Disease Index [OSDI] and McMonnies Dry Eye Questionnaire) and the Sjögren’s syndrome (SS) questionnaire (SSQ). Three hundred and eighteen patients (52% women and 48% men) with DED were included. Patient demographics were: 0 to 19 years (1%), 20 to 39 (25%), 40 to 59 (34%), 60 to 79 (35%) and 80 to 99 (5%). Xerostomia, defined as “daily symptoms of dry mouth the last three months” (as presented in SSQ) was reported by 23% of the patients. Female sex was more common among patients with xerostomia (81%) than among non-xerostomia patients (44%; Pxerostomia (60 ± 15 years) were older than those without xerostomia (51 ± 17; Pxerostomia patients (65%) than among non-xerostomia patients (35%; Pxerostomia had a higher OSDI score (19.0 ± 10.0) than those without xerostomia (12.9 ± 8.0; Pxerostomia patients had more pathological meibum expressibility (0.9 ± 0.7) than those without xerostomia (0.7 ± 0.8; P = 0.046). Comparisons of OSDI and ocular signs were performed after controlling for the effects of sex, age and the number of systemic prescription drugs used. In conclusion, xerostomia patients demonstrated a higher DED symptom load and had poorer meibum expressibility than non-xerostomia patients. PMID:27148875

  8. Radiation induced preparation of new multifunctional nanobiowebs

    International Nuclear Information System (INIS)

    New poly(vinylidene fluoride) based multi-functional (electroconductive, bioactive and catalytic) nano-biowebs were prepared through gamma radiation induced formation of silica and gold nanoparticles (Au NPs) within electrospun (poly vinylidene fluoride) nanofiberous membranes. The multifunctional membrane is designated as PVdF-silica/Au ESNFM. The morphology of PVdF-silica/Au ESNFM was examined by field emission scanning electron microscopy. The presence of Au particles was confirmed by energy dispersive x-ray analysis. The crystal structure of Au particles and the formation of silica were confirmed by X-ray diffraction analysis. The multi-functionalities (electroconductive, bioactive and catalytic) of the nano-webs were evaluated by cyclic voltammetry. Cytochrome c was immobilized to generate nano-bioweb (PVdF-silica/Au/cyt c ESNFM), which exhibited electrochemical responses to nitrite ions. - Highlights: ► New poly(vinylidene fluoride) based multi-functional (electroconductive, bioactive and catalytic) nano-biowebs were prepared through gamma radiation induced processes. ► The multi-functionalities (electroconductive, bioactive and catalytic) of the nano-webs are evaluated. ► Incorporation of gold nanoparticles into electrospun membranes imparts electroactivity and bioelectrocatalytic properties.

  9. Radiation induced conductivity in space dielectric materials

    International Nuclear Information System (INIS)

    The radiation-induced conductivity of some polymers was described mainly in literature by a competition between ionization, trapping/detrapping, and recombination processes or by radiation assisted ageing mechanisms. Our aim is to revise the effect of the aforementioned mechanisms on the complex evolution of Teflon® FEP under space representative ionizing radiation. Through the definition of a new experimental protocol, revealing the effect of radiation dose and relaxation time, we have been able to demonstrate that the trapping/recombination model devised in this study agrees correctly with the observed experimental phenomenology at qualitative level and allows describing very well the evolution of radiation induced conductivity with irradiation time (or received radiation dose). According to this model, the complex behavior observed on Teflon® FEP may be basically ascribed to the competition between electron/hole pairs generation and recombination: electrons are deeply trapped and act as recombination centers for free holes. Relaxation effects have been characterized through successive irradiations steps and have been again well described with the defined model at qualitative level: recombination centers created by the irradiation induce long term alteration on the electric properties, especially the effective bulk conductivity. One-month relaxation does not allow a complete recovery of the material initial charging behavior

  10. Radiation- induced aneuploidy in mammalian germ cells

    International Nuclear Information System (INIS)

    The ability of ionizing radiation to induce aneuploidy in mammalian germ cells has been investigated experimentally in the laboratory mouse using a variety of cytogenetic and genetic methods. These studies have provided unambiguous evidence of induced nondisjunction in both male and female germ cells when the effect of irradiation is screened in meiotic cells or preimplantation embryos. In contrast, however, cytogenetic analyses of post-implantation embryos and genetic assays for induced chromosome gains have not found a significant radiation effect. These apparently contradictory findings may be reconciled if (a) radiation induces tertiary rather than primary trisomy, or (b) induces embryo-lethal genetic damage, such as deletions, in addition to numerical anomalies. Either or both of these explanations may account for the apparent loss during gestation of radiation-induced trisomic embryos. Extrapolating from the information so far available, it seems unlikely that environmental exposure to low doses if low dose rate radiation will result in a detectable increase in the rate of aneuploidy in the human population. (author)

  11. Radiation-induced segregation in titanium alloys

    International Nuclear Information System (INIS)

    Radiation-induced segregation (RIS) of V, Mo, Nb, Ta, Zr, and Sn in binary titanium alloys was investigated to test the solute size effect correlation in hcp alloys. Undersize Mo segregates weakly toward the sinks. Nb and Ta, which are slightly oversize in Ti, undergo little or no RIS. Oversize Zr solute in Ti segregates away from the sinks, whereas undersize Ti solute in Zr is enriched at sinks. All of these results are in accord with the solute size effect correlation. Surprisingly, Sn, which is significantly oversize in Ti, appears to segregate very little. The postirradiation annealing of Ti-3V and Ti-8Al-1V-1Mo confirmed that segregation of undersize V toward sinks is radiation-induced. Measurements of temperature and dose dependence in binary and complex alloys showed that the degree of V segregation has a maximum at proportional6000C and obeys parabolic growth kinetics in its early stages but probably saturates at a rather low dose (proportional0.8 dpa). (orig.)

  12. Role of neurotensin in radiation-induced hypothermia in rats

    Energy Technology Data Exchange (ETDEWEB)

    Kandasamy, S.B.; Hunt, W.A.; Harris, A.H. (Armed Forces Radiobiology Research Institute, Bethesda, MD (USA))

    1991-05-01

    The role of neurotensin in radiation-induced hypothermia was examined. Intracerebroventricular (ICV) administration of neurotensin produced dose-dependent hypothermia. Histamine appears to mediate neurotensin-induced hypothermia because the mast cell stabilizer disodium cromoglycate and antihistamines blocked the hypothermic effects of neurotensin. An ICV pretreatment with neurotensin antibody attenuated neurotensin-induced hypothermia, but did not attenuate radiation-induced hypothermia, suggesting that radiation-induced hypothermia was not mediated by neurotensin.

  13. Pilocarpina no tratamento de xerostomia em pacientes submetidos à iodoterapia: estudo piloto Pilocarpine used to treat xerostomia in patients submitted to radioactive iodine therapy: a pilot study

    Directory of Open Access Journals (Sweden)

    Juliana Pereira Almeida

    2010-10-01

    Full Text Available Xerostomia é uma queixa tardia frequente associada à iodoterapia. Terapias para o tratamento desta morbidade podem proporcionar melhora na qualidade de vida dos pacientes com câncer de tireoide submetidos à iodoterapia adjuvante. OBJETIVOS: Relatar a experiência com o uso da pilocarpina no tratamento de xerostomia em pacientes com câncer de tireoide submetidos à iodoterapia adjuvante. MATERIAL E MÉTODOS: Cinco pacientes preencheram os critérios de inclusão e receberam 5mg de pilocarpina, 3 vezes ao dia, por uma semana. Os efeitos colaterais do medicamento e a resposta subjetiva à queixa de xerostomia após o tratamento foram avaliados. DESENHO DO ESTUDO: Trata-se de um estudo prospectivo, não-randomizado. RESULTADOS: Sudorese foi o efeito colateral mais comum com o uso da pilocarpina, seguido por cansaço e dor de cabeça. Dois pacientes relataram alívio da xerostomia com o uso da medicação, mas somente um paciente foi capaz de tolerar os efeitos colaterais. CONCLUSÕES: Pilocarpina parece aliviar os sintomas de xerostomia em pacientes submetidos à iodoterapia, já que o medicamento é capaz de estimular o fluxo salivar. No entanto, os efeitos colaterais observados inviabilizam seu uso por recusa por parte dos pacientes em continuar a terapia por períodos mais longos.Xerostomia complaint is very commonly associated to radioactive iodine therapy. Alternatives to treat this morbidity can offer better quality of life to patients with thyroid cancer submitted to adjuvant iodine therapy. AIM: to report on the experience with pilocarpine on the treatment of xerostomia in thyroid cancer patients submitted to adjuvant radioactive iodine therapy (RIT. MATERIALS AND METHODS: The five patients who met the inclusion criteria received 5mg of pilocarpine, 3 tid for one week. Side effects of the drug and subjective response to xerostomia complaints after treatment were evaluated. DESIGN: it is a prospective, non-randomized study. RESULTS

  14. Radiation-induced doping of conducting polymers

    International Nuclear Information System (INIS)

    Conducting polymers have the potential form many applications in electronics. The various patterns of doped regions of conducting polymers should be generated for the applications. Doping of conducting polymers is achieved by contact of the polymer with dopant or electrochemically. By these methods, doping occurs in the entire area exposed to the dopant. It is necessary to combine these doping techniques with lithography for achieving the patterned doping. Radiation-induced doping effects of conducting polymers have been reported. The doping is performed by irradiation of polymers in an atmosphere of gases, which do not react without irradiation, such as CH3Br, SF6, and N2O. If only the irradiated area was doped, patterned doping could be achieved without using lithography technique. We have elucidated the mechanism of the radiation-induced doping. The electrical conductivity was increased by irradiation the gas near the polymer film without irradiating the film itself. This result indicates that dopants were generated upon irradiation in the gas phase and the dopants react with the polymer. Hence, the pattern of doping is blurred by this method. We then developed another method of radiation-induced doping. Solid dopant precursor was coated on the polymer, and irradiation was performed. Figure 1 shows the results for poly(3-octylhitophene)(P3OT) by this method. A film of poly(3-octylthiophene) was prepared by spin coating from a solution of tetrahydrofuran on a quartz plate. The thickness of the film was approximately 100 nm. The polymer film was dried overnight at 80 degree C in a vacuum, and Au electrodes were evaporated on the films for electrical conductivity measurements. Saturated solution of 1,2,5,6,9,10-hexabromocyclododecane (HBCD) in 1-bromopropane was dropped on the film and dried at room temperature in a vacuum. The film was put in a vacuum chamber, which has a 0.2-mm-thick Be window. X rays entered through the Be window, and the films were irradiated

  15. Xerostomia due to systemic disease: a review of 20 conditions and mechanisms.

    Science.gov (United States)

    Mortazavi, H; Baharvand, M; Movahhedian, A; Mohammadi, M; Khodadoustan, A

    2014-07-01

    Xerostomia is a common complaint of nearly half of the elderly population and about one-fifth of younger adults. It causes several signs and symptoms, and compromise oral functions and health-related quality-of-life. Multiple reasons are proposed to describe the etiology of xerostomia such as local factors, psychogenic factors, and systemic diseases. In order to manage xerostomia effectively, identification of the main causality is mandatory. The aim of this review was to present systemic diseases leading to xerostomia with their mechanisms of action. We used various general search engines and specialized databases such as Google, Google Scholar, Yahoo, PubMed, PubMed Central, MedLine Plus, Medknow, EBSCO, ScienceDirect, Scopus, WebMD, EMBASE, and authorized textbooks to find relevant topics by means of Medical Subject Headings keywords such as "xerostomia," "hyposalivations," "mouth dryness," "disease," and "systemic." We appraised 97 English-language articles published over the last 40 years in both medical and dental journals including reviews, meta-analysis, original papers, and case reports. Upon compilation of relevant data, it was concluded that autoimmune diseases most frequently involve salivary glands and cause xerostomia followed by diabetes mellitus, renal failure, and graft-versus-host disease. Moreover, the underlying mechanisms of systemic disease-related xerostomia are: autoimmunity, infiltration of immunocompetent cells, granuloma formation, fibrosis and dehydration, deposition of proteinaceous substances, bacterial infection, and side-effects of medications. PMID:25221694

  16. Different saliva substitutes for treatment of xerostomia following radiotherapy. A prospective crossover study

    International Nuclear Information System (INIS)

    Background and purpose: xerostomia is an important chronic side effect of radiotherapy in the head and neck area. The authors investigated the efficacy of different artificial saliva compounds in patients with postirradiation xerostomia. Patients and methods: in 120 patients with xerostomia after radiotherapy for head and neck cancer, four different saliva substitute compounds (gel, carmellose spray, oil, mucin spray) were tested in a prospective crossover design. Xerostomia at baseline and under treatment with each compound was measured with a questionnaire approved in a pilot trial. Results: all compounds significantly improved xerostomia when compared to baseline situation (p < 0.0001). The gel was rated best, the carmellose spray was rated worst by the patients, but the single compounds did not differ significantly in their effects. In spite of this result, most patients chose the carmellose spray as their favorite compound. This is due to its good taste and easy handling, which play an important role for the acceptance of the products. Big individual differences in the preference of the single compounds were found. Conclusion: for most patients considerable relief from xerostomia can be reached by saliva substitutes. Thus, every patient with xerostomia should be given different artificial saliva compounds for a test period. This will help to find the individually best way to cope with the dry mouth. (orig.)

  17. Postradiotherapy quality of life for head-and-neck cancer patients is independent of xerostomia

    International Nuclear Information System (INIS)

    Purpose: To determine the relationship between quality of life (QOL) and xerostomia over time for patients undergoing radiotherapy (RT) for head-and-neck cancer in a prospective clinical trial. Methods and materials: Patients with head-and-neck cancer were randomized to pilocarpine (n = 65) vs. placebo (n = 65) during RT. QOL was measured using the McMaster Head and Neck Radiotherapy Questionnaire (HNRQ). Xerostomia was measured on a linear analog scale. No statistically significant differences were observed between arms; all 130 patients were analyzed together. Results: Baseline QOL data were obtained for 98.5% of participants. The baseline HNRQ score of 5.7 declined significantly to 4.0 (p <0.0001) by RT Week 6 and returned to baseline (5.8) by 6 months after treatment. This represents a large, clinically important change of 1.7 of 7 (24%; effect size 1.34). The decline in HNRQ score during RT paralleled the onset of xerostomia on the linear analog scale (r = 0.36 at 1 month). After treatment, the QOL scores recovered without improvement in xerostomia. The trajectory of the linear analog scale score resembled that of the HNRQ's single xerostomia question (r = 0.75 at 1 month). Conclusion: Quality of life recovers to baseline after RT, despite persistent xerostomia. Either a response shift occurs or xerostomia in the absence of acute mucositis has a relatively small influence on overall QOL

  18. Radiation-induced mutation at minisatellite loci

    International Nuclear Information System (INIS)

    We are studying the radiation-induced increase of mutation rate in minisatellite loci in mice and humans. Minisatellite mutations were scored by multilocus DNA fingerprint analysis in the progeny of γ-irradiated and non-irradiated mice. The frequency of mutation in offspring of irradiated males was 1.7 higher that in the control group. Germline mutation at human minisatellite loci was studied among children born in heavily polluted areas of the Mogilev district of Belarus after the Chernobyl accident and in a control population. The frequency of mutation assayed both by DNA fingerprinting and by eight single locus probes was found to be two times higher in the exposed families than in the control group. Furthermore, mutation rate was correlated with the parental radiation dose for chronic exposure 137Cs, consistent with radiation-induction of germline mutation. The potential use of minisatellites in monitoring germline mutation in humans will be discussed

  19. Radiation-induced grafting onto wool

    International Nuclear Information System (INIS)

    Radiation-induced grafting tests were done on single wool fibres. Different vinyl monomers were used for this purpose and they were grafted in twenty different solvents which were selected for their swelling effiency and solvent parameters. The tests were done once with and once without the addition of water. The presence of water causes the polymer uptake to increase considerably. Formic acid/methanol and methanol were found to be the most suitable solvent systems, as they have the highest hydrogen-bond interaction effiency. The moisture uptake of wool depends on the hydrophily and hydrophoby of the grafted polymers. The single-fibre tests serve as a basis for analogous grafting tests on wool fabrics. The permanent- press was improved by graftng with hydrophoric polymers and polymers with a high glass-transition temperature

  20. Radiation-induced mutations in mammals

    International Nuclear Information System (INIS)

    The aims of the proposed project are to provide a better basis for extrapolation of animal data to man. Genetic endpoint, strain and species comparisons are made, which will provide critical experimental data regarding strategies in extrapolating laboratory animal data to man. Experiments were conducted to systematically compare the spontaneous and radiation-induced mutation rates for recessive specific-locus, dominant cataract and enzyme activity alleles in the mouse as well as a comparison of the mutation rate in the mouse and hamster for dominant cataract and enzyme activity alleles. The comparison of the radiation-dose response for recessive specific-locus and dominant cataract mutations are extended. Selected mutations are characterized at the genetic, biochemical and molecular levels. (R.P.) 5 refs., 3 tabs

  1. Radiation-induced brachial plexus paralysis

    International Nuclear Information System (INIS)

    Fifteen patients with radiation-induced brachial plexus paralysis were studied. Thirteen women had been treated for breast cancer. Two men developed symptoms and signs following radiation therapy for lung cancer. The brachial plexus paralysis initially was not static and progressed, but spontaneous arrest with permanent residual paralysis was seen in three patients. Three were noted to have intractable pain, but the major complaint of the remaining 12 was the inability to use their hands. The ten patients on whom an earlier operation directed at the brachial plexus had been performed were not relieved. Two of these were later considered excellent candidates for a tendon transfer in the hand. One did not desire surgery. The other underwent operation and showed marked improvement of her grasp and general hand function

  2. Radiation-induced spinal cord hemorrhage (hematomyelia

    Directory of Open Access Journals (Sweden)

    Amit Agarwal

    2014-12-01

    Full Text Available Intraspinal hemorrhage is very rare and intramedullary hemorrhage, also called hematomyelia, is the rarest form of intraspinal hemorrhage, usually related to trauma. Spinal vascular malformations such intradural arteriovenous malformations are the most common cause of atraumatic hematomyelia. Other considerations include warfarin or heparin anticoagulation, bleeding disorders, spinal cord tumors. Radiation-induced hematomyelia of the cord is exceedingly rare with only one case in literature to date. We report the case of an 8 year old girl with Ewing’s sarcoma of the thoracic vertebra, under radiation therapy, presenting with hematomyelia. We describe the clinical course, the findings on imaging studies and the available information in the literature. Recognition of the clinical pattern of spinal cord injury should lead clinicians to perform imaging studies to evaluate for compressive etiologies.

  3. Gamma-radiation-induced grafting onto wool

    International Nuclear Information System (INIS)

    Radiation-induced grafting studies have been carried out on loose wool fibres. Different vinyl monomers were used and they were grafted in different solvents which were selected on the basis of their swelling efficiency and solubility parameters. The treatments were performed once with and once without the addition of water. The presence of water caused the polymer uptake to increase considerably. Formic acid/methanol and methanol accelerate the grafting process best, since they have the highest hydrogen-bond interaction efficiency. The moisture uptake of grafted wool decreases. X-ray and differential scanning calorimetry tests show unambiguously that grafting occurs in different morphological areas, depending on the type of polymer. The single fibre studies served as basis for analogous tests on wool fabrics (Part II). (author)

  4. Radiation-induced electron migration along DNA

    International Nuclear Information System (INIS)

    Radiation-induced electron migration along DNA is a mechanism by which randomly produced stochastic energy deposition events can lead to nonrandom types of damage along DNA manifested distal to the sites of the initial energy deposition. Electron migration along DNA is significantly influenced by the DNA base sequence and DNA conformation. Migration along 7 base pairs in oligonucleotides containing guanine bases was observed for oligonucleotides irradiated in solution which compares to average migration distances of 6 to 10 bases for Escherichia coli DNA irradiated in solution and 5.5 base pairs for Escherichia coli DNA irradiated in cells. Evidence also suggests that electron migration can occur preferentially in the 5' to 3' direction along DNA. Our continued efforts will provide information regarding the contribution of electron transfer along DNA to formation of locally multiply damaged sites created in DNA by exposure to ionizing radiation

  5. Radiation-induced emulsion polymerization of tetrafluoroethylene

    International Nuclear Information System (INIS)

    The radiation-induced emulsifier-free emulsion polymerization of tetrafluoroethylene (TFE) has been studied at initial pressure 2 - 25 kg/cm2 and temperature 300 - 1100C for dose rate 0.57 x 104 - 3.0 x 104 rad/hr. Polytetrafluoroethylene (PTFE), a hydrophobic polymer, forms as a stable latex in the absence of an emulsifier. Stability of the latex is governed by the dose rate/TFE pressure ratio; it increases with sufficient TFE monomer. PTFE particles produced in this polymerization system are stable due to the carboxyl end groups and adsorption of OH- and HF on the particles. PTFE latex of molecular weight higher than 2 x 107 is obtained by addition of a radical scavenger such as hydroquinone. The molecular weight of PTFE can be measured from the heat of crystallization conveniently with high reliability, which was found in the course of study on the melting and crystallization behavior. (author)

  6. Management of radiation-induced rectal bleeding.

    Science.gov (United States)

    Laterza, Liboria; Cecinato, Paolo; Guido, Alessandra; Mussetto, Alessandro; Fuccio, Lorenzo

    2013-11-01

    Pelvic radiation disease is one of the major complication after radiotherapy for pelvic cancers. The most commonly reported symptom is rectal bleeding which affects patients' quality of life. Therapeutic strategies for rectal bleeding are generally ignored and include medical, endoscopic, and hyperbaric oxygen treatments. Most cases of radiation-induced bleeding are mild and self-limiting, and treatment is normally not indicated. In cases of clinically significant bleeding (i.e. anaemia), medical therapies, including stool softeners, sucralfate enemas, and metronidazole, should be considered as first-line treatment options. In cases of failure, endoscopic therapy, mainly represented by argon plasma coagulation and hyperbaric oxygen treatments, are valid and complementary second-line treatment strategies. Although current treatment options are not always supported by high-quality studies, patients should be reassured that treatment options exist and success is achieved in most cases if the patient is referred to a dedicated centre. PMID:24101202

  7. Radiation-induced damage to DNA

    International Nuclear Information System (INIS)

    This short survey focuses on the main radiation-induced base lesions that have been identified within cellular DNA. For this purpose, sensitive assays that are aimed at measuring a few modifications per 107 normal bases were set-up. In that respect high performance liquid chromatography - tandem mass spectrometry (CLHP-MS/MS) was found to be able to single out the formation of 9 oxidized nucleosides and two modified nucleo-bases out of the 70 oxidative base lesions that have been identified in model systems. As a striking result, it was found that in the DNA of γ-irradiated human monocytes, the formamide-pyrimidine derivative of guanine is produced in a higher yield than the ubiquitous 8-oxo-7,8-dihydro-guanine damage, both arising from the same radical precursor. However, relatively high doses of ionizing radiation (> 20 Gy) have to be applied in order to detect an increase in the level of the damage. This is due to the low efficiency for both low and high LET radiations to generate oxidative damage to DNA on one hand and the occurrence of artifactual oxidation of the overwhelming normal bases during DNA extraction on the other hand. Interestingly, a modified comet assays that involves the combined use of the alkaline single gel electrophoretic technique and DNA repair N-glycosylases has allowed the detection of three main types of radiation-induced damage within the dose range 0.3 Gy -10 Gy. It appears that the total of frank DNA strand breaks and alkali-labile sites is similar to the sum of oxidized pyrimidine bases and modified purine bases that are recognized by the endonuclease Ill protein and the formamide-pyrimidine DNA N-glycosylase respectively. (author)

  8. Radiation-induced premature menopause: a misconception

    International Nuclear Information System (INIS)

    Purpose: To disprove the common view that women who have undergone irradiation to fields excluding the pelvis are at risk for radiation-induced premature menopause, we reviewed menstrual function and fertility among women treated with subtotal lymphoid irradiation for Hodgkin's Disease. Methods and Materials: Treatment and follow-up records of all women less than age 50 at the time of diagnosis of Stage I or II supradiaphragmatic Hodgkin's Disease, treated with subtotal lymphoid irradiation alone and enrolled in radiotherapy trials from 1967 to 1985, were reviewed. In addition, patients were surveyed regarding their menstrual status and fertility history. Results: Thirty-six women, aged 10 to 40 years, with normal menstrual function at the time of Hodgkin's diagnosis, were identified. Mean follow-up was 14 years, with a range of 1.25-22.75 years. The average radiation dose to mantle and paraaortic fields was 40-44 Gy; the calculated scatter radiation dose to the pelvis at the ovaries was 3.2 Gy. There were 38 pregnancies in 18 women; all offspring are normal. One of 36 women (2.7%) experienced premature menopause. The reported rate of premature menopause in women who have not undergone irradiation is 1-3%; not significantly different than the rate in our study. There is a syndrome whereby antibodies to several endocrine organs occur (including the ovary), which is associated with premature ovarian failure. This syndrome may be associated with prior radiation to the thyroid, such as that given by mantle-irradiation for Hodgkin's Disease. We report such a case. Conclusion: There is little risk of premature menopause in women treated with radiation fields that exclude the pelvis. Women with presumed radiation-induced premature menopause warrant an evaluation to exclude other causes of ovarian failure, such as autoimmune disorders

  9. Study on the Clinical Significance and Related Factors of Thirst and Xerostomia in Maintenance Hemodialysis Patients

    Directory of Open Access Journals (Sweden)

    Wei-Feng Fan

    2013-10-01

    Full Text Available Aims: To analyse the clinical significance and related factors of thirst and xerostomia and to find methods to alleviate thirst and xerostomia in maintenance hemodialysis (MHD patients. Methods: Forty-two MHD patients were included for observational study and eleven patients were enrolled for crossover trial. Thirst was assessed by 100-mm visual analog scales (VAS and dialysis thirst inventory (DTI. Meanwhile, xerostomia was assessed by VAS and xerostomia inventory (XI. Depression, kidney disease quality of life (KDQOL, salivary flow rates and inter dialytic weight gain (IDWG were measured. Data were analyzed by ANOVA and correlation coefficient was used to assess the correlations between continuous variables. The results of crossover trial were investigated by two-sample T-tests. Results: Strong positive correlations among DTI, VAS thirst score, XI and VAS xerostomia score were found (P=0.000. Daily IDWG was positively correlated with VAS thirst score (r=0.315, P=0.042 and DTI(r=0.391, P=0.010. UWS (unstimulated whole saliva was negatively correlated with VAS xerostomia score (r=-0.308, P=0.048. Residual urine output was negatively correlated with DTI (r=-0.402, P=0.008, VAS xerostomia score (r=-0.461, P=0.002 and XI (r=-0.403, P=0.008. In the crossover trial, DTI, XI, IDWG2d, IDWG3d, VAS thirst and xerostomia score were significantly reduced by the use of chewing gum (P=0.000, 0.001, 0.009, 0.017, 0.038, 0.001. The VAS thirst score, DTI and IDWG3d were significantly reduced by receiveing straw (P=0.016, 0.003, 0.049. Conclusion: Thirst and xerostomia might affect the quality of life in MHD patients. Both chewing gum and straw could decrease thirst and IDWG.

  10. Radiation induced mitochondrial biogenesis: limitations of metabolic viability based assays in measuring radiation induced cell death

    International Nuclear Information System (INIS)

    Many techniques based on metabolic viability of cells employing MTT and MTS assay are being widely used to measure the radiation and chemotherapeutics induced cell death, because of their high throughput capability. These assays are based on mitochondrial potential of cells to convert the substrate in to measurable products and remain dependent on this notion that all the cells untreated and treated will have equal mitochondrial content and metabolic potential. However, it is increasingly becoming clear that treatment induced changes in both mitochondrial content and metabolism can influence the metabolic viability of cells and radiation is a potential mitochondrial biogenesis inducer. Therefore, we tested if metabolic viability based assays are true measure of radiation induced cell death using the widely used cell lines like RAW264.7, HEK293, NIH3T3, J774.1, BMG-1, MDAMB231, MCF-7, A549 and HeLa. Cells were irradiated with gamma rays (60Co) and enumerated cell numbers (by hemocytometer) and metabolic viability using MTT assay at 24 and 48 hours after exposure. At all the absorbed doses (0-5 Gy), the extent of reduction in cell number was found to be larger than the decrease in formazan formation in all the cell lines tested. Further, this difference in the cell number and formazan formation varied significantly among the cell lines. To test if the increased formazan formation is due to increased mitochondrial content per cell, we analyzed the radiation induced mitochondrial biogenesis using mitochondria specific dye mitotracker red and found a 1.5 to 2 fold increase in mitochondrial content. These findings suggest that radiation induces mitochondrial biogenesis that enhances the metabolic potential leading to increased formazan formation. Therefore, conclusions drawn on radiation induced cytotoxicity based on metabolic viability assays are likely to be erroneous as it may not correlate with growth inhibition and/or loss of clonogenic survival. (author)

  11. Feasibility of OCT to detect radiation-induced esophageal damage in small animal models (Conference Presentation)

    Science.gov (United States)

    Jelvehgaran, Pouya; Alderliesten, Tanja; Salguero, Javier; Borst, Gerben; Song, Ji-Ying; van Leeuwen, Ton G.; de Boer, Johannes F.; de Bruin, Daniel M.; van Herk, Marcel B.

    2016-03-01

    Lung cancer survival is poor and radiotherapy patients often suffer serious treatment side effects. The esophagus is particularly sensitive leading to reduced food intake or even fistula formation. Only few direct techniques exist to measure radiation-induced esophageal damage, for which knowledge is needed to improve the balance between risk of tumor recurrence and complications. Optical coherence tomography (OCT) is a minimally-invasive imaging technique that obtains cross-sectional, high-resolution (1-10µm) images and is capable of scanning the esophageal wall up to 2-3mm depth. In this study we investigated the feasibility of OCT to detect esophageal radiation damage in mice. In total 30 mice were included in 4 study groups (1 main and 3 control groups). Mice underwent cone-beam CT imaging for initial setup assessment and dose planning followed by single-fraction dose delivery of 4, 10, 16, and 20Gy on 5mm spots, spaced 10mm apart. Mice were repeatedly imaged using OCT: pre-irradiation and up to 3 months post-irradiation. The control groups received either OCT only, irradiation only, or were sham-operated. We used histopathology as gold standard for radiation-induced damage diagnosis. The study showed edema in both the main and OCT-only groups. Furthermore, radiation-induced damage was primarily found in the highest dose region (distal esophagus). Based on the histopathology reports we were able to identify the radiation-induced damage in the OCT images as a change in tissue scattering related to the type of induced damage. This finding indicates the feasibility and thereby the potentially promising role of OCT in radiation-induced esophageal damage assessment.

  12. Synchrotron Radiation-Induced Desorption from a NEG-Coated Vacuum Chamber

    CERN Document Server

    Chiggiato, P

    1999-01-01

    When the whole inner surface of a vacuum chamber is coated with a non-evaporable getter film, very low static and dynamic pressures are expected after activation. In an accelerator environment this could result in a longer beam lifetime, in a lower risk of pressure bumps, and in a lower level of bremsstrahlung radiation due to the beam-gas interactions. To substantiate these favourable characteristics a Ti-Zr-V coated stainless steel chamber has been tested on a dedicated beamline at the ESRF. It is shown that a large reduction of the synchrotron radiation-induced desorption occurs after activation.

  13. Synchrotron radiation-induced desorption from a NEG-coated vacuum chamber [of ESRF beamline

    CERN Document Server

    Chiggiato, P

    2001-01-01

    When the whole inner surface of a vacuum chamber is coated with a non-evaporable getter film, very low static and dynamic pressures are expected after activation. In an accelerator environment this could result in a longer beam lifetime, in a lower risk of pressure bumps, and in a lower level of bremsstrahlung radiation due to the beam-gas interactions. To substantiate these favourable characteristics a Ti- Zr-V coated stainless-steel chamber has been tested on a dedicated beamline at the ESRF. It is shown that a large reduction of the synchrotron radiation-induced desorption occurs after activation. (10 refs).

  14. Urethral dilation in prostatic malignancies for obstructive uropathy secondary to radiation-induced edema

    International Nuclear Information System (INIS)

    This paper evaluates transurethral prostatic balloon dilation in patients with symptomatic obstructive uropathies secondary to radiation-induced edema during external beam irradiation for prostatic adenocarcinoma. From 1987 to 1990, six patients with obstructive uropathy during external beam were treated with balloon dilation. With ultrasound-directed needle biopsy, fewer patients undergo TURP for diagnosis of malignancy and relief of symptoms. The urethra may become compromised by prostate edema during irradiation, increasing obstructive symptoms or urinary retention. Six patients presented requiring relief of symptoms. Options included Turp, catheter drainage, or urethral balloon dilation. All were treated with dilation. Three patients were treated at completion of therapy, and two patients underwent dilation after obstruction

  15. Radiation-induced cancer in Japan

    Energy Technology Data Exchange (ETDEWEB)

    Yamashita, Shoji; Sekizuka, Eiichi [National Saitama Hospital, Wako (Japan); Yamashita, Hisao [Keio Cancer Center, Tokyo (Japan); Takami, Akira [Yamawaki Coll., Tokyo (Japan); Kubo, Atsushi [Keio Univ., Tokyo (Japan). School of Medicine

    2001-12-01

    Results of two questionnaire surveys on radiation-induced malignant tumors conducted in 1977 and 1984 in Japan are briefly summarized. A total of 234 universities and general hospitals (139 in 1977, and 95 in 1984) responded and provided data from 1945 to 1977 and from 1978 to 1984. The number of patients with benign disease who developed secondary malignant tumors following radiation therapy was 150 in the first survey (1977) and 86 in the second survey (1984). The underlying benign diseases of these patients included tuberculous lymphadenitis, skin disease, hemangioma, and thyroid disease, and the most frequent radiation-induced malignant tumors in these patients were malignant tumors of the pharynx (80), cancer of the larynx (26), malignant tumors of the thyroid gland (22), cancer of the esophagus (219), and skin cancer (21). In patients with head and neck diseases the highest correlation between underlying benign disease and radiation-induced malignant tumors was between cervical tuberculous lymphadenitis and tumors of the pharynx (67 patients), followed by cancer of the larynx (19), and malignant tumors of the thyroid gland (11). There were also correlations between thyroid disease and malignant tumors of the thyroid gland (8 patients), hemangioma and skin cancer (7), and skin disease and skin cancer (8). The ratio of the observed values to predicted values (O/E ratio) in these patients was highest for cancer of the pharynxy (118), followed by cancer of the parotid gland (42), skin cancer (31), cancer of the esophagus (22), malignant tumors of the thyroid gland (21), and cancer of the larynx (16). The number of patients with malignant tumors who developed secondary malignant tumors following radiation therapy was 140 in 1977 and 108 in 1984, and the underlying malignant tumors in these patients included tumors of the uterus (106), breast (32), and head and neck (80). The most frequent secondary malignant tumors were soft tissue tumors, followed by leukemia

  16. Xerostomia after Radiotherapy for Oral and Oropharyngeal Cancer

    DEFF Research Database (Denmark)

    Kaae, Julie Killerup; Stenfeldt, Lone; Eriksen, Jesper Grau

    2016-01-01

    these patients. OBJECTIVES: The purpose of this study was to investigate the possibility to mechanically stimulate residual saliva function by using tasteless and sugar-free chewing gum. It was hypothesized that tasteless and sugar-free chewing gum could immediately increase salivary flow and...... RT 2-8 months prior to participation and suffered from xerostomia. Samples of unstimulated and chewing gum-stimulated saliva were obtained at the entry into the study (Visit 1). For 2 weeks, patients used chewing gum on a regular basis whereupon saliva measurements were repeated to verify the changes...... (Visit 2). An abbreviated EORTC H&N35 questionnaire was completed for both visits. A small control group consisting of young and healthy individuals also tested the chewing gum. RESULTS: Twenty patients completed the study and an increase in saliva flow was observed for 14 patients. Before and after...

  17. Biotechnological advances in neuro-electro-stimulation for the treatment of hyposalivation and xerostomia.

    Science.gov (United States)

    Lafaurie, Gloria; Fedele, Stefano; López, Rafael Martín-Granizo; Wolff, Andy; Strietzel, Frank; Porter, Stephen R; Konttinen, Yrjö T

    2009-02-01

    Treatment of xerostomia is a common clinical challenge in the oral medicine practice. Although some treatments have been used to improve the symptoms of xerostomia, none is completely satisfactory for the patients who suffer of this alteration. In the last years non-pharmacological treatments based on electro-stimulation for the treatment of xerostomia have been developed. This review is aimed at presenting new developments for the treatment of xerostomia, applying neuro-electro-stimulation by miniaturized intra-oral electro-stimulators. These devices increase salivary secretion and improve symptoms of oral dryness. Their effect is obtained by means of stimulation of the lingual nerve, in whose proximity the electrodes of the apparatus are placed. The objective of this mechanism is both to directly stimulate the salivary glands controlled by that nerve and to enhance the salivary reflex. Clinical studies have been carried out that have demonstrated the wetting effect of the method described in this article. PMID:19179954

  18. Study about xerostomia, salivary flow rate and systemic conditions of postmenopausal women

    Directory of Open Access Journals (Sweden)

    Flávia Lopes Carvalho

    2008-01-01

    Full Text Available Objective: To make a quantitative evaluation of salivary flow and occurrence of xerostomia in post-menopausal women, according to thesystemic condition related by the patients. Methods: The sample was composed of 20 post-menopausal women, who were submitted to anamnesis and completely stimulated sialometry. Results: The results revealed that 50% of the women examined related the presence of xerostomia; hyposalivation was more present than normal salivary flow and low salivary flow; among the patients who related having systemic ailments, cardiovascular diseases were the most frequent, followed by depression and nervousness. Conclusion: It was concluded that xerostomia and quantitative alteration in salivary flow are common among post-menopausal women, and that ailments of a psychological nature were shown to be related to the manifestation of xerostomia.

  19. The effects of low-level laser therapy on xerostomia (mouth dryness)

    OpenAIRE

    Pavlić Verica

    2012-01-01

    Introduction. Xerostomia is a subjective complaint of mouth/oral dryness, caused by a reduction in normal salivary secretion due to different causes. Even though there are many available treatment modalities to enhance salivary flow, the therapy often remains unsatisfactory. The low-level laser therapy (low-level laser irradiation, photo-biomodulation) has been extensively used as a new, non-invasive approach and advantageous tool for reduction of xerostomia. Therefore, the aim of this ...

  20. Penegakan Diagnosis Dan Penatalaksanaan Pembuatan Gigitiruan Penuh Pada Pasien Edentulus Penderita Xerostomia

    OpenAIRE

    Hubban Nasution

    2009-01-01

    Xerostomia merupakan temuan klinis yang sering ditemukan dalam praktek sehari-hari pada pasien edentulus, tetapi jarang terdeteksi oleh praktisi dokter gigi sehingga nantinya setelah pemakaian gigitiruan penuh (GTP) akan menimbulkan permasalahan pada pasien. Untuk mengatasi hal tersebut, seorang prostodontis harus memiliki pengetahuan yang cukup untuk mampu menegakkan diagnosis xerostomia dan membuat GTP yang sesuai untuk pasien tersebut. Tujuan penulisan skripsi ini adalah untuk menjelaskan...

  1. Effectiveness of malic acid 1% in patients with xerostomia induced by antihypertensive drugs

    OpenAIRE

    Gómez Moreno, Gerardo; Guardia, Javier; Aguilar Salvatierra, Antonio; Cabrera Ayala, Marible; Maté Sánchez de Val, José Eduardo; Calvo Guirado, José Luis

    2012-01-01

    Objectives: Assessing the clinical effectiveness of a topical sialogogue on spray (malic acid, 1%) in the treatment of xerostomia induced by antihypertensive drugs. Study Design: This research has been carried out through a randomized double-blind clinical trial. 45 patients suffering from hypertensive drugs-induced xerostomia were divided into 2 groups: the first group (25 patients) received a topical sialogogue on spray (malic acid, 1%) whereas the second group (20 patients) received a plac...

  2. The presence of subjective feelings of xerostomia in the institutionalized elderly

    OpenAIRE

    Petrovski, Mihajlo; Minovska, Ana; Ivanovski, Kiro

    2014-01-01

    Introduction: The presence of subjective feelings of dry mouth is the most common oral problem in the institutionalized elderly. Purpose: to assess the subjective presence of xerostomia in the institutionalized elderly. Materials and method: Seventy individuals, older than 65 years and institutionalized in a particular nursing home, were evaluated. The subjective presence of xerstomia was determined. To determine the level of expressiveness of xerostomia, a questionnaire recommended b...

  3. Pengobatan Xerostomia Pada Pasien Gigi Tiruan Dengan Menggunakan Titik-Titik Lokal akupuntur Pada Wajah

    OpenAIRE

    Lumban Toruan, Merry Chritie Ellora

    2008-01-01

    Xerostomia yang berarti mulut kering berasal dari kata xeros = kering dan stoma = mulut. Xerostomia merupakan karakteristik klinis dari suatu keadaan berkurangnya produksi saliva. Produksi saliva yang berkurang dapal menimbulkan gejala-gejala klinis, seperti : kering dan pecah-pecah pada Iidah dan bibir; pipi kering; lidah berlapis; gingivitis; kandidiasis; dan merah pada mukosa bibir, lidah dan pipi; adanya karies rampan. Keadaan mulut yang kering dapat terlihat berupa kesulitan mengunya...

  4. Prevalence of xerostomia in patients attending Shorish dental speciality in Sulaimani city

    OpenAIRE

    Abdullah, Mustafa Jamel

    2015-01-01

    Objectives: The aim of this study was to investigate the prevalence of xerostomia among dental patients and explore the possible risk factors and symptoms associated with this condition. Patient and Methods: The prevalence of xerostomia and its associations were investigated among patients (n=1132) who were visiting the department of oral medicine at shorish dental speciality in sulaimani city. The age range was between 10-79 years. 512 (45.2%) of participants were males and 620 (54.8%) were ...

  5. Study about xerostomia, salivary flow rate and systemic conditions of postmenopausal women

    OpenAIRE

    Flávia Lopes Carvalho; Luciana Freitas Gomes e Silva; Fernanda Ferreira Lopes; Ana Emília Figueiredo de Oliveira

    2008-01-01

    Objective: To make a quantitative evaluation of salivary flow and occurrence of xerostomia in post-menopausal women, according to thesystemic condition related by the patients. Methods: The sample was composed of 20 post-menopausal women, who were submitted to anamnesis and completely stimulated sialometry. Results: The results revealed that 50% of the women examined related the presence of xerostomia; hyposalivation was more present than normal salivary flow and low salivary flow; among the ...

  6. Radiation induced mutations for breeding of sorghum

    International Nuclear Information System (INIS)

    Several sorghum cultivars of Mali were irradiated with different doses of gamma rays and compared with the Caudatum types. Radio-sensitivity studies suggested that the local types were less sensitive to radiation than the introduced types. Whereas the local varieties survived dose of 300 Gy, in Caudatum types, seed germination and growth were significantly reduced at 200 Gy. Several agronomically important mutants were obtained among the progeny of the local types. Some of the mutants were shorter and had improved panicle characteristics. Radiation-induced variation was observed in several characters such as plant height, resistance to lodging, plant architecture, drought tolerance, panicle length and compactness, seed size and color, seed quality (viterous or floury) and protein content, glume color and structure, flowering data (early and late maturity), and tillering capacity. One mutant was drought tolerant. Promising mutants were selected and are presently under evaluation in the National List Trials to confirm their potential and future release. Selected variants have been also crossed with local types to obtain promising material. (author). 8 refs, 2 tabs

  7. Radiation-induced cranial nerve palsy

    International Nuclear Information System (INIS)

    Twenty-five patients with 35 cranial nerve palsies were seen at the Fondation Curie during follow-up after radical radiotherapy for head and neck tumors. The twelfth nerve was involved in 19 cases, the tenth in nine, and the eleventh in five; the fifth and second nerves were involved once each and in the same patient. The twelfth nerve was involved alone in 16 patients and the tenth nerve alone in three, with multiple nerves involved in the remaining six patients. The palsy was noted from 12 to 145 months after diagnosis of the tumor. The latency period could be correlated with dose so that the least square fit equation representing NSD vs delay is NSD = 2598--Delay (in months) x 4.6, with a correlation coefficient of -0.58. The distinction between tumor recurrence and radiation-induced nerve palsy is critical. It can often be inferred from the latency period but must be confirmed by observation over a period of time

  8. Gamma Radiation-Induced Template Polymerization Technique

    International Nuclear Information System (INIS)

    Gamma radiation induced copolymerization of acrylamide sodiumacrylate (AM-AANa) in the presence and absence of the polymer additive was studied at low monomer concentration(1.4M/l). The results showed that the exponents of the dose rate for the polymerization rate was found to be 1.3 and 1.4 in the absence and in the presence of the polymer additive respectively. The molecular weight of the formed polymer increased by addition of the polymer to the system. In the presence of the polymer the comonomers polymerize on the added polymer. In the absence of the added polymer the comonomers polymerize according to the copolymerization process at the initial stage of the copolymerization. While at high conversion the residual comonomers polymerize on the formed macromolecular chains of the produced polymer. These studies showed that the copolymerization in the presence of added polymer is completely template copolymerization while in the absence of the polymer the copolymerization process is only template process with a high conversion

  9. Retroviruses in radiation-induced lymphomas

    International Nuclear Information System (INIS)

    The nucleotide sequence of RadLV/VL3(T+L+), the thymotropic and leukemogenic entity of the in-vitro propagated radiation leukemia virus complex (RadLV/VL3), is that of a recombinant retrovirus. The gag, pol and most of the env gene are very similar to the homologous regions of Akv MuLV. The 3' end of the env gene and the LTR appear to have derived from a xenotropic MuLV. However, the LTR has acquired a feature shared by other lymphomagenic MuLVs. This feature consists in sequence rearrangements resulting in the generation of presumed enhancer elements. RadLV/VL3(T+L+)-specific proviral sequences were found adjacent to the c-myc gene in several virus-induced thymic lymphomas of the rat, suggesting that the enhancer elements might play a role in lymphomagenesis. However, it was found that the presence of a provirus at a specific DNA site can lead to an in-vitro growth advantage and to clonal cell selection independently of a lymphomagenic process. The authors conclude from this observation that clonal appearance of an integrated provirus in cultured radiogenic lymphoma cells does not necessarily reflect a viral induction of radiation-induced leukemogenesis. (author)

  10. Effect of Radiation-Induced Amorphization on Smectite Dissolution

    International Nuclear Information System (INIS)

    Effects of radiation-induced amorphization of smectite were investigated using artificial irradiation. Beams of 925 MeV Xenon ions with radiation dose reaching 73 MGy were used to simulate the effects generated by alpha recoil nuclei or fission products in the context of high level nuclear waste repository. Amorphization was controlled by X-ray diffraction, transmission electron microscopy, and Fourier transform infrared spectroscopy. An important coalescence of the smectite sheets was observed which lead to a loss of interparticle porosity. The amorphization is revealed by a loss of long-range structure and accompanied by dehydroxylation. The dissolution rate far-from-equilibrium shows that the amount of silica in solution is two times larger in the amorphous sample than in the reference clay, a value which may be enhanced by orders of magnitude when considering the relative surface area of the samples. Irradiation-induced amorphization thus facilitates dissolution of the clay-derived material. This has to be taken into account for the safety assessment of high level nuclear waste repository, particularly in a scenario of leakage of the waste package which would deliver alpha emitters able to amorphize smectite after a limited period of time. (authors)

  11. Protective Effect of HSP25 on Radiation Induced Tissue Damage

    International Nuclear Information System (INIS)

    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

  12. Radiation induced degradation of dyes-An overview

    International Nuclear Information System (INIS)

    Synthetic dyes are a major part of our life. Products ranging from clothes to leather accessories to furniture all depend on extensive use of organic dyes. An unfortunate side effect of extensive use of these chemicals is that huge amounts of these potentially carcinogenic compounds enter our water supplies. Various advanced oxidation processes (AOPs) including the use of high-energy radiation have been developed to degrade these compounds. In this review, dye decoloration and degradation as a result of its exposure to high energy radiation such as gamma radiation and pulsed electron beam are discussed in detail. The role of various transient species such as ·H, ·OH and eaq- are taken into account as reported by various researchers. Literature citations in this area show that eaq- is very effective in decolorization but is less active in the further degradation of the products formed. The degradation of the dyes is initiated exclusively by ·OH attack on electron-rich sites of the dye molecules. Additionally, various parameters that affect the efficiency of radiation induced degradation of dyes, such as effect of radiation dose, oxygen, pH, hydrogen peroxide, added ions and dye classes are also reviewed and summarized. Lastly, pilot plant application of radiation for wastewater treatment is briefly discussed.

  13. Temperature Dependence of Radiation Induced Conductivity in Insulators

    International Nuclear Information System (INIS)

    This study measures Radiation Induced Conductivity (RIC) of Low Density Polyethylene (LDPE) over temperatures ranging from ∼110 K to ∼350 K. RIC occurs when incident ionizing radiation deposits energy and excites electrons into the conduction band of insulators. Conductivity was measured when a voltage was applied across vacuum-baked, thin film LDPE polymer samples in a parallel plate geometry. RIC was calculated as the difference in sample conductivity under no incident radiation and under an incident ∼4 MeV electron beam at low incident fluxes of 10-4-10-1 Gr/sec. The steady-state RIC was found to agree well with the standard power law relation, σRIC = kRIC·D ring Δ between conductivity, σ and adsorbed dose rate, D ring . Both the proportionality constant, kRIC, and the power, δ, were found to be temperature dependant above ∼250 K, with behavior consistent with photoconductivity models developed for localized trap states in disordered semiconductors. Below ∼250 K, kRIC and Δ exhibited little change. The observed difference in temperature dependence might be related to a structural phase transition seen at Tβ∼256 K in prior studies of mechanical and thermodynamic properties of LDPE.

  14. Sleep quality in patients with xerostomia: a prospective and randomized case-control study.

    Science.gov (United States)

    Lopez-Jornet, Pia; Lucero Berdugo, Maira; Fernandez-Pujante, Alba; C, Castillo Felipe; Lavella C, Zamora; A, Pons-Fuster; J, Silvestre Rangil; Silvestre, Francisco Javier

    2016-01-01

    Objectives To investigate sleep quality, anxiety/depression and quality-of-life in patients with xerostomia. Materials and methods This prospective, observational, cross-sectional study was conducted among a group of xerostomia patients (n = 30) compared with 30 matched control subjects. The following evaluation scales were used to assess the psychological profile of each patient: the Hospital Anxiety and Depression Scale, the Oral Health Impact Profile-14 (OHIP-14), the Xerostomia Inventory, the Pittsburgh Sleep Quality Index (PSQI) and the Epworth Sleepiness Scale (ESS). Results The PSQI obtained 5.3 3 ± 1.78 for patients with xerostomia compared with 4.26 ± 1.01 for control subjects (p = 0.006); ESS obtained 5.7 ± 2.1 for test patients vs 4.4 0 ± 1 for control subjects (p = 0.010). Statistical regression analysis showed that xerostomia was significantly associated with depression (p = 0.027). Conclusions Patients with xerostomia exhibited significant decreases in sleep quality compared with control subjects. PMID:26473793

  15. Trismus, xerostomia and nutrition status in nasopharyngeal carcinoma survivors treated with radiation.

    Science.gov (United States)

    Chen, Y-J; Chen, S-C; Wang, C-P; Fang, Y-Y; Lee, Y-H; Lou, P-J; Ko, J-Y; Chiang, C-C; Lai, Y-H

    2016-05-01

    The aims of the study were to: (1) examine levels of trismus, xerostomia and nutritional status; (2) compare levels of trismus, xerostomia and nutritional status in patients with nasopharyngeal carcinoma (NPC) receiving different types of radiation modalities; and (3) identify factors related to NPC survivors' risk status for malnutrition and existing malnutrition. A cross-sectional study with consecutive sampling was conducted. NPC survivors were recruited from otolaryngology/oncology outpatient clinics in a medical centre in Northern Taiwan. Study measures included (1) Mandibular Function Impairment Questionnaire, (2) Xerostomia Questionnaire, (3) Mini Nutrition Assessment, (4) Hospital Anxiety and Depression Scale - Depression subscale, and (5) Symptom Severity Scale. A total of 110 subjects were recruited. Those receiving intensity-modulated radiation therapy had less trismus and xerostomia than patients receiving two-dimensional radiation therapy. Patients with female gender, advanced stage, completion of treatments within 1 year, higher levels of depression, more severe trismus and higher symptom severity tended to have malnutrition or were at risk of malnutrition. Trismus and xerostomia are long-term problems in some NPC survivors and may contribute to malnutrition. To better manage a patient's trismus and xerostomia and to enhance nutritional status, clinicians should develop a patient-specific care programme based on careful assessment and targeted measures to improve oral function and insure adequate nutritional intake. PMID:25495287

  16. Hyperbaric Oxygen Therapy for Radiation-Induced Cystitis and Proctitis

    Energy Technology Data Exchange (ETDEWEB)

    Oliai, Caspian; Fisher, Brandon; Jani, Ashish; Wong, Michael; Poli, Jaganmohan; Brady, Luther W. [Department of Radiation Oncology, Drexel University College of Medicine, Philadelphia, Pennsylvania (United States); Komarnicky, Lydia T., E-mail: lydia.komarnicky-kocher@drexelmed.edu [Department of Radiation Oncology, Drexel University College of Medicine, Philadelphia, Pennsylvania (United States)

    2012-11-01

    Purpose: To provide a retrospective analysis of the efficacy of hyperbaric oxygen therapy (HBOT) for treating hemorrhagic cystitis (HC) and proctitis secondary to pelvic- and prostate-only radiotherapy. Methods and Materials: Nineteen patients were treated with HBOT for radiation-induced HC and proctitis. The median age at treatment was 66 years (range, 15-84 years). The range of external-beam radiation delivered was 50.0-75.6 Gy. Bleeding must have been refractory to other therapies. Patients received 100% oxygen at 2.0 atmospheres absolute pressure for 90-120 min per treatment in a monoplace chamber. Symptoms were retrospectively scored according to the Late Effects of Normal Tissues-Subjective, Objective, Management, Analytic (LENT-SOMA) scale to evaluate short-term efficacy. Recurrence of hematuria/hematochezia was used to assess long-term efficacy. Results: Four of the 19 patients were lost to follow-up. Fifteen patients were evaluated and received a mean of 29.8 dives: 11 developed HC and 4 proctitis. All patients experienced a reduction in their LENT-SOMA score. After completion of HBOT, the mean LENT-SOMA score was reduced from 0.78 to 0.20 in patients with HC and from 0.66 to 0.26 in patients with proctitis. Median follow-up was 39 months (range, 7-70 months). No cases of hematuria were refractory to HBOT. Complete resolution of hematuria was seen in 81% (n = 9) and partial response in 18% (n = 2). Recurrence of hematuria occurred in 36% (n = 4) after a median of 10 months. Complete resolution of hematochezia was seen in 50% (n = 2), partial response in 25% (n = 1), and refractory bleeding in 25% (n = 1). Conclusions: Hyperbaric oxygen therapy is appropriate for radiation-induced HC once less time-consuming therapies have failed to resolve the bleeding. In these conditions, HBOT is efficacious in the short and long term, with minimal side effects.

  17. Pilocarpina no tratamento de xerostomia em pacientes submetidos à iodoterapia: estudo piloto Pilocarpine used to treat xerostomia in patients submitted to radioactive iodine therapy: a pilot study

    OpenAIRE

    Juliana Pereira Almeida; Luiz Paulo Kowalski

    2010-01-01

    Xerostomia é uma queixa tardia frequente associada à iodoterapia. Terapias para o tratamento desta morbidade podem proporcionar melhora na qualidade de vida dos pacientes com câncer de tireoide submetidos à iodoterapia adjuvante. OBJETIVOS: Relatar a experiência com o uso da pilocarpina no tratamento de xerostomia em pacientes com câncer de tireoide submetidos à iodoterapia adjuvante. MATERIAL E MÉTODOS: Cinco pacientes preencheram os critérios de inclusão e receberam 5mg de pilocarpina, 3 ve...

  18. Radiation-induced gene expression in human subcutaneous fibroblasts is predictive of radiation-induced fibrosis

    International Nuclear Information System (INIS)

    Background and purpose: Breast cancer patients show a large variation in normal tissue reactions after ionizing radiation (IR) therapy. One of the most common long-term adverse effects of ionizing radiotherapy is radiation-induced fibrosis (RIF), and several attempts have been made over the last years to develop predictive assays for RIF. Our aim was to identify basal and radiation-induced transcriptional profiles in fibroblasts from breast cancer patients that might be related to the individual risk of RIF in these patients. Materials and methods: Fibroblast cell lines from 31 individuals with variable risk of RIF (grouped into five classes from low to high risk) were irradiated with two different schemes: 1 x 3.5 Gy with RNA isolated 2 and 24 h after irradiation, and a fractionated scheme with 3 x 3.5 Gy in intervals of 24 h with RNA isolated 2 h after the last dose. RNA was also isolated from non-treated fibroblasts. Transcriptional differences in basal and radiation-induced gene expression profiles were investigated using 15K cDNA microarrays, and results analyzed by both SAM and PAM. Results: Sixty differentially expressed genes were identified by applying SAM on 10 patients with the highest risk of RIF and the four patients with the lowest risk of RIF after the fractionated scheme. The genes were associated with known functions in processes like apoptosis, extracellular matrix remodelling/cell adhesion, proliferation and ROS scavenging. A minimum set of 18 genes were identified that could differentiate high risk from low risk-patients after the fractionated scheme. Conclusions: The classifier of 18 genes may provide basis for a predictive assay for normal tissue reactions after radiotherapy, and provide new insight into the molecular mechanisms of RIF

  19. Explanation of diagnostic criteria for radiation-induced liver diseases

    International Nuclear Information System (INIS)

    National occupational health standard-Diagnostic Criteria for Radiation-Induced Liver Diseases has been passed by the committee of diagnostic criteria for radiation disease and in line for approval by the Ministry of Health. Based on the extensive research of literature, this standard was enacted according to the relevant laws and regulations. It is mainly used for diagnosis of radiation-induced liver diseases, and it also can serve as a guide to diagnose liver disease induced by medical radiation. To implement this standard, and to diagnose and treat the radiation-induced liver diseases patient correctly and promptly, the contents of this standard were interpreted in this article. (authors)

  20. Radiation-induced phase transition of paraffins

    International Nuclear Information System (INIS)

    When irradiated by the 500 kV electron at a dose of about 1.5 x 10-3 C/cm2, normal paraffins exhibit a solid-solid phase transition; a transition from a triclinic form to an orthorhombic one in n-C22H46 and n-C24H50 and from a monoclinic form to an orthorhombic one in n-C28H58, n-C36H74 and n-C44H90. The transition to a phase with high energy (orthorhombic phase) accommodates the radiation-induced stresses. The excess strain energy produced by cross-links in crystals is assumed to be equal to the enthalpy change of the phase transition, and the number of cross-links required to induce the phase transition is estimated at one per volume of about ten molecular chains. To compare with irradiated crystals, mixed crystals are prepared from solutions of binary mixtures of n-C23H48 and n-C24H50 and of n-C24H50 and n-C25H52. When the content of impurities (n-C23H48 or n-C25H52) reaches 10% in molar fraction, the crystal form of mixed crystals changes from the stable triclinic one to the unstable orthorhombic one. Thus, the number of lattice imperfections of mixed lattice is also estimated at one per volume of ten molecules. It is concluded from the above two estimations that the phase transition occurs when the content of lattice imperfections reaches the value of one per ten molecular chains and the value does not depend on the type of imperfections in these paraffins. (author)

  1. Radiation-induced changes in the breast

    International Nuclear Information System (INIS)

    Thirty-six postirradiation breast tissue specimens from 30 patients with breast cancer treated by primary radiation therapy were evaluated to define the effects of therapeutic doses of ionizing radiation on the residual non-neoplastic breast tissue. Breast tissue was sampled an average of 30.4 months after completion of therapy because of the development of new clinically or mammographically detectable abnormalities within the treated breasts. The average radiation dose was 6,399 rad to the primary tumor area and 4,778 rad to the remainder of the breast. Breast tissue sections from 35 nonirradiated patients served as control specimens. The most characteristic radiation effects consisted of atypical epithelial cells in the terminal duct lobular unit (TDLU) associated with lobular sclerosis and atrophy. These changes were present in all of the irradiated patients but varied in severity and extent among patients and within individual patients. This variation was not related to the presence or absence of carcinoma elsewhere in the specimen, radiation dose, patient age, time to postirradiation tissue sampling, or use of adjuvant chemotherapy. Epithelial atypia in larger ducts, stromal changes, and vascular changes were less frequent but were always accompanied by prominent TDLU changes. Radiation effects could usually be clearly distinguished from carcinoma involving the TDLU by the absence of both cellular proliferation and distention of the involved TDLU and by the preservation of cellular polarity and cohesion in areas of presumed radiation-induced injury. Familiarity with these changes is of considerable practical importance in that they must be distinguished from new or recurrent neoplasms

  2. A case of radiation induced cancer

    Energy Technology Data Exchange (ETDEWEB)

    Ozawa, Kazuyoshi; Tsuchikawa, Kohzo; Sato, Akira; Kato, Joji (Nippon Dental Univ., Niigata (Japan). School of Dentistry at Niigata)

    1994-06-01

    A case of carcinoma on the right buccal mucosa is presented. The case was suspected to have been induced by irradiation therapy for a carcinoma on the left buccal mucosa. An external radiotherapy, 6-MeV Linac, had been done for the carcinoma on the left buccal mucosa in a 55-year-old female, with single lateral direction from the left to the right in 1977. In 1985, a papillary lesion on the right buccal mucosa was detected, and histological examination revealed a papilloma without atypism. In 1991, as an ulcer on the right upper buccal fold as well as three papillary lesions in the central portion of the right buccal mucosa were found, the patient was referred to our clinic. Microscopical findings were consistent with the early invasive carcinomas. A surgical excision of these whole lesions and skin graft were completed. The criteria of this case for the suspicion of radiation-induced carcinoma were as follows. There was a long latent period of 14 years. The previous dose of irradiation, 60 Gy, was sufficient. The right buccal mucosa was involved in the radiation field. A severe scar on the left cheek resulted from the previous irradiation. Anatomically, there is no evidence of the secondary carcinoma on the right buccal mucosa with the primary carcinoma on the left buccal mucosa. No evidence for recurrence of the tumors on both sides of buccal mucosa has been detected so far. Further observations will be necessary to detect other tumors in the irradiated field later on. (author).

  3. Radiation induced promising mutants in Cowpea

    International Nuclear Information System (INIS)

    Cowpea (Vigna unguiculata L. Walp.) is an important legume crop of the tropics and subtropics of Asia, Africa and America. Breeding objectives in recent years have been to combine high yields with upright growth habit, bushy dwarf determinate plant type, early maturity and large seed size in addition to resistance to biotic and abiotic stresses. With a view to achieving these objectives and creating additional - variability, the seeds of an elite variety V-130 were irradiated with 200 Gy of gamma rays, and a number of morphological mutants were isolated. The mutants with desirable characters like erect growth habit, dwarf, large seed size, and high pod number were isolated in the M2 generation and studied further in subsequent generations for their yield potential and other characteristics. The dwarf plant mutant TCM 77-4, characterised by reduced plant height, bushy growth, large seed size and absence of tendril bred true when grown in rabi seasons, but behaved like parent in respect of growth habit in kharif season. It was far superior to the parent in respect of seed size in all the seasons. The mutant is envisaged to be the most suitable for rice fallows. Among the several promising mutants with large seed size, the mutant TCM 13-5 showed a test weight of 16.8 g against 8.8 g of the parent. A mutant with large pod number designated as TCM 121-8 showed promise with its very high yield, when grown in summer albeit with delayed maturity. Several mutants with maturity similar to that of the parent have shown higher seed yield. The variability generated through the radiation- induced mutation is being utilised for creating novel high yielding early maturing varieties of cowpea. (author)

  4. Radiation-induced carotid artery atherosclerosis

    International Nuclear Information System (INIS)

    Purpose: Carotid arteries frequently receive significant doses of radiation as collateral structures in the treatment of malignant diseases. Vascular injury following treatment may result in carotid artery stenosis (CAS) and increased risk of stroke and transient ischaemic attack (TIA). This systematic review examines the effect of radiotherapy (RT) on the carotid arteries, looking at the incidence of stroke in patients receiving neck radiotherapy. In addition, we consider possible surrogate endpoints such as CAS and carotid intima-medial thickness (CIMT) and summarise the evidence for radiation-induced carotid atherosclerosis. Materials and methods: From 853 references, 34 articles met the criteria for inclusion in this systematic review. These papers described 9 studies investigating the incidence of stroke/TIA in irradiated patients, 11 looking at CAS, and 14 examining CIMT. Results: The majority of studies utilised suboptimally-matched controls for each endpoint. The relative risk of stroke in irradiated patients ranged from 1.12 in patients with breast cancer to 5.6 in patients treated for head and neck cancer. The prevalence of CAS was increased by 16–55%, with the more modest increase seen in a study using matched controls. CIMT was increased in irradiated carotid arteries by 18–40%. Only two matched-control studies demonstrated a significant increase in CIMT of 36% and 22% (p = 0.003 and <0.001, respectively). Early prospective data demonstrated a significant increase in CIMT in irradiated arteries at 1 and 2 years after RT (p < 0.001 and <0.01, respectively). Conclusions: The incidence of stroke was significantly increased in patients receiving RT to the neck. There was a consistent difference in CAS and CIMT between irradiated and unirradiated carotid arteries. Future studies should optimise control groups

  5. Delayed Radiation-Induced Vasculitic Leukoencephalopathy

    International Nuclear Information System (INIS)

    Purpose: Recently, single-fraction, high-dosed focused radiation therapy such as that administered by Gamma Knife radiosurgery has been used increasingly for the treatment of metastatic brain cancer. Radiation therapy to the brain can cause delayed leukoencephalopathy, which carries its own significant morbidity and mortality. While radiosurgery-induced leukoencephalopathy is known to be clinically different from that following fractionated radiation, pathological differences are not well characterized. In this study, we aimed to integrate novel radiographic and histopathologic observations to gain a conceptual understanding of radiosurgery-induced leukoencephalopathy. Methods and Materials: We examined resected tissues of 10 patients treated at Yale New Haven Hospital between January 1, 2009, and June 30, 2010, for brain metastases that had been previously treated with Gamma Knife radiosurgery, who subsequently required surgical management of a symptomatic regrowing lesion. None of the patients showed pathological evidence of tumor recurrence. Clinical and magnetic resonance imaging data for each of the 10 patients were then studied retrospectively. Results: We provide evidence to show that radiosurgery-induced leukoencephalopathy may present as an advancing process that extends beyond the original high-dose radiation field. Neuropathologic examination of the resected tissue revealed traditionally known leukoencephalopathic changes including demyelination, coagulation necrosis, and vascular sclerosis. Unexpectedly, small and medium-sized vessels revealed transmural T-cell infiltration indicative of active vasculitis. Conclusions: We propose that the presence of a vasculitic component in association with radiation-induced leukoencephalopathy may facilitate the progressive nature of the condition. It may also explain the resemblance of delayed leukoencephalopathy with recurring tumor on virtually all imaging modalities used for posttreatment follow-up.

  6. Evaluation of xerostomia following intensity modulated radiotherapy (IMRT) for head and neck cancer patients

    International Nuclear Information System (INIS)

    This study was done to evaluate xerostomia following intensity modulated radiotherapy for patients with head and neck cancer, and to analyze the correlation between the dosimetric parameters and xerostomia parameters. From February till October 2003, 13 patients with 3 months of follow-up were evaluated for xerostomia after being treated for head and neck cancer with IMRT. Their median age was 57 years (range:43 ∼ 77). Xerostomia were assessed with a 4-question xerostomia questionnaire score (XQS) and a test for salivary flow rates (unstimulated and stimulated). The patients were also given a validated LENT SOMA scale (LSC) questionnaire. The evaluations were completed before radiation therapy (pre-RT) and at 1 and. 3 months after radiation therapy (RT). We evaluated xerostomia at pre-RT, 1 and, 3 months after RT. The association between the xerostomia parameters (XQS and LSC) and salivary flow rates (unstimulated and stimulated: USFR and SSFR) was assessed at 1 and 3 months after RT. All 13 patients showed no significant changes in XQS, LSC and Salivary Flow rates. As a result, we couldn't find out about xerostomia development. Based on the total mean parotid dose, 3,500 cGy, we divided these patients into two groups. The 8 patients (< 3,500 cGy) showed no significant changes in XQS, LSC and Salivary Flow rates. However, in 5 patients (≥ 3,500 cGy), there was a significant increase in USFR and, SSFR at 3 months after RT, and for the XQS and, LSC at 1 and 3 months after RT. The correlation between XQS and, LSC, and USFR and, SSFR in all patients (13) was significant at 3 months after RT. The correlation had a tendency to the decrease for USFR and, SSFR in proportion to the increase of XQS and, LSC. Base on the results of this study, IMRT seem to be an effective treatment to significantly decrease the xerostomia. XQS and, LSC seem to be a effective tool for predicting the xerostomia. A total parotid gland mean dose of < 3,500 cGy should be a planning goal if

  7. Xerostomia and its predictors following parotid-sparing irradiation of head-and-neck cancer

    International Nuclear Information System (INIS)

    Purpose: To assess long-term xerostomia in patients receiving parotid-sparing radiation therapy (RT) for head-and-neck cancer, and to find the patient and therapy-related factors that affect its severity. Patients and Methods: From March 1994 through January 2000, 84 patients received comprehensive bilateral neck RT using conformal and multisegmental intensity-modulated RT (IMRT) aiming to spare the major salivary glands. Before RT and periodically through 2 years after the completion of RT, salivary flow rates from each of the major salivary glands were selectively measured. At the same time intervals, each patient completed an 8-item self-reported xerostomia-specific questionnaire (XQ). To gain a relative measure of the effect of RT on the minor salivary glands, whose output could not be measured, the surfaces of the oral cavity (extending to include the surface of the base of tongue) were outlined in the planning CT scans. The mean doses to the new organ ('oral cavity') were recorded. Forty-eight patients receiving unilateral neck RT were similarly studied and served as a benchmark for comparison. Factors predicting the XQ scores were analyzed using a random-effects model. Results: The XQ was found to be reliable and valid in measuring patient-reported xerostomia. The spared salivary glands which had received moderate doses in the bilateral RT group recovered to their baseline salivary flow rates during the second year after RT, and the spared glands in the unilateral RT group, which had received very low doses, demonstrated increased salivary production beyond their pre-RT levels. The increase in the salivary flow rates during the second year after RT paralleled an improvement in xerostomia in both patient groups. The improvement in xerostomia was faster in the unilateral compared with the bilateral RT group, but the difference narrowed at 2 years. The major salivary gland flow rates had only a weak correlation with the xerostomia scores. Factors found to be

  8. Indomethacin attenuation of radiation-induced hyperthermia does not modify radiation-induced motor hypoactivity

    Energy Technology Data Exchange (ETDEWEB)

    Ferguson, J.L.; Kandasamy, S.B.; Harris, A.H.; Davis, H.D.; Landauer, M.R. [Armed Forces Radiobiology Research Inst., Bethesda, MD (United States)

    1996-09-01

    Exposure of rats to 5-10 Gy of ionizing radiation produces hyperthermia and reduces motor activity. Previous studies suggested that radiation-induced hyperthermia results from a relatively direct action on the brain and is mediated by prostaglandins. To test the hypothesis that hypoactivity may be, in part, a thermoregulatory response to this elevation in body temperature, adult male rats were given indomethacin (0.0, 0.5, 1.0, and 3.0 mg/kg, intraperitoneally), a blocker of prostaglandin synthesis, and were either irradiated (LINAC 18.6 MeV (nominal) high-energy electrons, 10 Gy at 10 Gy/min, 2.8 {mu}sec pulses at 2 Hz) or sham-irradiated. The locomotor activity of all rats was then measured for 30 min in a photocell monitor for distance traveled and number of vertical movements. Rectal temperatures of irradiated rats administered vehicle only were elevated by 0.9{+-}0.2degC at the beginning and the end of the activity session. Although indomethacin, at the two higher doses tested, attenuated the hyperthermia in irradiated rats by 52-75%, it did not attenuate radiation-induced reductions in motor activity. These results indicate that motor hypoactivity after exposure to 10 Gy of high-energy electrons is not due to elevated body temperature or to the increased synthesis of prostaglandins. (author)

  9. Characterization of a Novel Radiation-Induced Sarcoma Cell Line

    Czech Academy of Sciences Publication Activity Database

    Lang, J.; Zhu, W.Z.; Nokes, B.; Sheth, S.G.; Novák, Petr; Fuchs, L.; Watts, G.; Futscher, B. W.; Mineyev, N.; Ring, A.

    2015-01-01

    Roč. 111, č. 6 (2015), s. 669-682. ISSN 0022-4790 Institutional support: RVO:60077344 Keywords : Sarcoma * radiation-induced * breast * cancer Subject RIV: FD - Oncology ; Hematology Impact factor: 3.244, year: 2014

  10. Two pediatric cases of high dose radiation-induced meningiomas

    Energy Technology Data Exchange (ETDEWEB)

    Nagai, Miho [National Yokosuka Hospital, Kanagawa (Japan); Nagashima, Goro; Fujimoto, Tsukasa; Aoyagi, Masaru; Takasato, Yoshio

    2001-10-01

    There have been many reports of low dose radiation-induced meningiomas, and the number of reports of high dose radiation-induced meningiomas has been increasing recently. In this report, we present two cases of pediatric radiation-induced meningiomas, one 14 years after 36 Gy of radiation therapy for medulloblastoma and the other 8 years after 20 Gy of local radiation therapy for germinoma. Both patients underwent surgical removal of the meningiomas. The case of medulloblastoma was later revealed to be basal cell phacomatosis syndrome. Basal cell phacomatosis syndrome is a disease that occurs as a result of abnormality of chromosome 9. We speculate that the occurrence of radiation-induced meningioma may have been related to the basic genetic vulnerability of the patients. (author)

  11. Concomitant pilocarpine during head and neck irradiation is associated with decreased posttreatment xerostomia

    International Nuclear Information System (INIS)

    Purpose: To retrospectively compare subjective postirradiation xerostomia scores of patients who received concomitant oral pilocarpine during radiotherapy for head and neck cancer and 3 months thereafter with those of similar cohorts who did not receive pilocarpine. Methods and Materials: Subjective xerostomia was assessed using a visual analog scale xerostomia questionnaire that measured oral dryness, oral comfort, difficulty with sleep, speech, and eating. The concomitant pilocarpine group had both parotid glands in the initial field treated to at least 45 Gy and received 5 mg pilocarpine hydrochloride four times per day (q.i.d.) beginning on the first day of radiotherapy and continuing for 3 months after completion of radiation. The control cohort had also received at least 45 Gy to both parotid glands and had not received pilocarpine at the time of evaluation. Scores on the visual analog scale were averaged and compared using the Student's t-test. Results: Seventeen patients who received concomitant pilocarpine during head and neck irradiation and 18 patients who had not been treated with pilocarpine were available for follow-up. The mean intervals between completion of radiation and evaluation of xerostomia were 17 months and 16 months, respectively. Only one of the pilocarpine-treated patients was still taking pilocarpine at the time of evaluation. For each of the individual components of xerostomia scored on the visual analog scale, as well as the composite of all components, the group that had received oral pilocarpine during radiation had significantly less xerostomia (p < 0.01 for each). Conclusions: The use of 5 mg oral pilocarpine q.i.d. during radiotherapy for head and neck cancer and 3 months thereafter was associated with significantly less subjective xerostomia than that reported by a similar cohort of patients who had not received pilocarpine. The continued use of pilocarpine does not appear to be necessary to maintain this benefit in most patients

  12. An Evidence-Based Review Literature About Risk Indicators and Management of Unknown-Origin Xerostomia

    Directory of Open Access Journals (Sweden)

    Farzaneh Agha-hosseini

    2013-01-01

    Full Text Available Objective: This evidence-based article reviews risk indicators and management of unknown-origin xerostomia. Xerostomia and hyposalivation refer to different aspects of dry mouth. Xerostomia is a subjective sensation of dry mouth, whilst hyposalivation is defined as an objective assessment of reduced salivary flow rate. About 30% of the elderly (65 years and older experience xerostomia and hyposalivation. Structural and functional factors, or both may lead to salivary gland dysfunction.Study Selection: The EBM literature search was conducted by using the medical literature database MEDLINE via PubMed and OvidMedline search engines. Results were limited to English language articles (1965 to present including clinical trials (CT, randomized controlled trials (RCT, systematic reviews and review articles. Case control or cohort studies were included for the etiology.Results: Neuropathic etiology such as localized oral alteration of thermal sensations, saliva composition change (for example higher levels of K, Cl, Ca, IgA, amylase, calcium, PTH and cortisol, lower levels of estrogen and progesterone, smaller salivary gland size, and illnesses such as lichen planus, are risk indicators for unknown-origin xerostomia. The management is palliative and preventative. Management of symptoms includes drug administration (systemic secretogogues, saliva substitutes and bile secretion-stimulator, night guard, diet and habit modifications. Other managements may be indicated to treat adverse effects.Conclusion: Neuropathic etiology, saliva composition change, smaller salivary gland size, and illnesses such as oral lichen planus can be suggestive causes for unknown-origin xerostomia. However, longitudinal studies will be important to elucidate the causes of unknown-origin xerostomia.

  13. Clarithromycin Attenuates Radiation-Induced Lung Injury in Mice

    OpenAIRE

    Lee, Seung Jun; Yi, Chin-ok; Heo, Rok Won; Song, Dae Hyun; Cho, Yu Ji; Jeong, Yi Yeong; Kang, Ki Mun; Roh, Gu Seob; Lee, Jong Deog

    2015-01-01

    Radiation-induced lung injury (RILI) is a common and unavoidable complication of thoracic radiotherapy. The current study was conducted to evaluate the ability of clarithromycin (CLA) to prevent radiation-induced pneumonitis, oxidative stress, and lung fibrosis in an animal model. C57BL/6J mice were assigned to control, irradiation only, irradiation plus CLA, and CLA only groups. Test mice received single thoracic exposures to radiation and/or oral CLA (100 mg/kg/day). Histopathologic finding...

  14. Physical mechanisms of radiation induced creep in metals

    International Nuclear Information System (INIS)

    Analysis of available experimental data has been conducted. It enables to correlate reliably the character of evolution of dislocation structure of irradiated materials with different stages of radiation induced creep. This provides reliable basis for the general conclusions concerning the character of some parametric dependences of deformation rate of these materials. Analysis of different modern theoretical models enables to evaluate regions of their applicability and their relative significance for radiation induced creep description. 20 refs.; 2 figs.; 1 tab

  15. Radiation-induced aftertreatment of textiles

    International Nuclear Information System (INIS)

    Techniques to improve the properties of textiles by graft polymerization of acrylic acid, metacrylic acid, etc. on natural and synthetic fibers by irradiation of electron beam or γ ray were developed and put into practical use. Such graft polymerization by irradiation is effective technique to give synthetic fibers hydrophilic property, heat-shrinkage resistance, dye affinity, static electricity prevention, combustion resistance, etc.. Irradiation is also applied for adhesion of nonwoven fabric, coating processing of textiles, and printing processing of fabrics. Thus, the processing of textiles by radiation, especially electron beam, is effective to give new properties to textiles, but its importance has been also recognized as energy saving and public nuisance-avoiding processes. A great deal of energy reduction can be expected by electron beam irradiation method. (Kobatake, H.)

  16. Radiation-induced processes and defects in alkali and alkaline-earth borate crystals

    International Nuclear Information System (INIS)

    The paper presents the results of a study of the radiation-induced processes and defects in nonlinear optical crystals Li2B4O7 (LTB), LiB3O5 (LBO), CsLiB6O10, KB5O8·4H2O, β-BaB2O4. It was revealed that a pulsed electron beam irradiation at 290 K forms the radiation-induced pairs of the 'vacancy--interstitial atom' defects in the cation sublattice of these crystals. This gives rise to a creation of metastable electronic (interstitial atom) and hole (small-radius polaron near the cation vacancy) centers in high concentrations. Optical hole-transitions from the local level of the trapped hole centers to the valence band states are responsible for the transient optical absorptions (TOA) of borates in the visible and UV spectral ranges. A sublattice of the weakly bound mobile lithium cations in LTB and LBO favors a spatial separation of the radiation-induced pair defects 'hole polaron near Li-vacancy--mobile interstitial Li0 atom'. Their decay rated by the electron-hole nonradiative tunnel recombination determines a peculiar feature of the TOA decay kinetics in LTB and LBO

  17. Effect of heme oxygenase-1 on radiation-induced skin injury

    International Nuclear Information System (INIS)

    Objective: To investigate the effect of heme oxygenase-1 (HO-1) on the acute radiation-induced skin injury by gene transfer. Methods: Thirty-three male SD rats were randomly divided into three groups as PBS-injected group, Ad-EGFP-injected group and Ad-HO-1-injected group (n=11). In each group, three rats were used for determining the expression of target gene and the other rats were irradiated on the buttock skin with 40 Gy electron beam generated by a linear accelerator. Immediately after irradiation, rats were administered with a subcutaneous injection of PBS, Ad-EGFP or Ad-HO-1, respectively. Subsequently, the skin reactions were measured twice a week using the semi-quantitative skin injury scale. Results: The strong positive expression of HO-1 was observed in subcutaneous dermal tissue after injection of Ad-HO-1. Compared to the PBS-injected group or the Ad-EGFP-injected group, a significant mitigation of skin injury was observed in Ad-HO-1-injected mice 14 d after irradiation (q=0.000-0.030, P<0.05). Conclusions: HO-1 could significantly mitigate radiation-induced acute skin injury and Ad-HO-1 could be used to treat radiation-induced skin injury. (authors)

  18. Radiation induced effects in carbon materials

    International Nuclear Information System (INIS)

    Full text: The level of safe exploiting nuclear reactor depends on radiation-induced changes of the neutron-absorbing material shape. The dimensional effects in carbon materials including those containing boron carbides B4C, irradiated in the water-water cooled reactor of the INP AS RUz operating at the power of 10 MW were studied in the temperature interval of 300-1500 K up to the integral fluence of 4·1021 neutrons per cm2. Two methods of dimensional control were used: dilatometry (change of linear dimensions and calculation of the volume change) and X-ray diffraction analysis (determination of the lattice parameters and the elementary unit volume). In all samples of low-ash and pyrolytic graphite (oriented parallel and normal to the pressing axis), irradiated up to the fluences above 1021 n/cm2 in the temperature range of 700-1100 K the shrinkage of linear dimensions was found from 6 to 8 %. While there occurred the primary swelling of graphite in the temperature interval of 300-700 K. The secondary swelling began at the fluence of 4·1021 cm-2 and 1100 K. Basing on these data, the neutron-absorbing graphite rods, containing B4C particles, were tested under the analogous irradiation conditions. The comparison of the rates of B4C swelling and graphite matrix shrinkage showed, that unfortunately, there was not gained the complete compensation of the swelling at the expense of shrinkage. The samples of fiber graphite, which were studied under the same conditions as the above mentioned, turned out stable in dimensions - changes in linear dimensions did not exceed 2 %. The X-diffraction study of ultra disperse amorphous carbon film irradiated in the water reactor discovered the formation of a denser carbon phase. The position of the observed structure reflection with d/n = 7.5 A did not correspond to the peaks of stable single phases of fullerenes C60 and C70. Perhaps, the irradiation creates a mixture of these phases in the amorphous matrix

  19. Radiation Induced Degradation of Galactomannan Polysaccharides

    International Nuclear Information System (INIS)

    Galactomannans are neutral polysaccharides that occur in substantial amounts in the endosperm of the seeds of some leguminous plants. Structurally they consist of a β(1-4)-D-mannose backbone to which galactose units are attached α(1-6). Among various galactomannans known, guar gum (GG), tara gum (TG) and locust bean gum (LBG) are the most widely used in applications in, for example, the food, pharmaceutical, and chemical industries as thickening agents or stabilizers due mainly to the high viscosity they impart at low concentrations. In many industrial applications, the use of low molecular weight polysaccharides is essential. For example, guar solutions, which are used as hydraulic fracturing fluids in oil and gas recovery, need to be degraded to facilitate the outflow of oil. In addition, to understand the solution properties of guar as well as other water-soluble biopolymers, it is often necessary to degrade the native polymer to prepare samples with various molecular weights (MW. Degradation of polysaccharides has been widely studied. Though acid and enzymatic hydrolysis are most common, other methods such as thermal, γ-irradiation, extrusion, ultrasonication and free radical degradation are also reported. In this study, radiation induced degradation of galactomannan polysaccharides has been investigated. GG, TG and LBG samples were irradiated with gamma rays in air at ambient temperature in the solid state at low dose rate. The change in their molecular weights was determined by SEC analysis and the change in their viscosity values as a function of temperature and irradiation dose was determined. Chain scission yields, G(S), and degradation rates were calculated. As a result of irradiation the molecular weight and viscosity of all galactomannans sharply decreased up to 50 kGy, no significant change was observed beyond this dose value. We observed that mannose-to-galactose ratio is an important factor controlling the G(S) and degradation rate of

  20. Pharmacological activation of the EDA/EDAR signaling pathway restores salivary gland function following radiation-induced damage.

    Science.gov (United States)

    Hill, Grace; Headon, Denis; Harris, Zoey I; Huttner, Kenneth; Limesand, Kirsten H

    2014-01-01

    Radiotherapy of head and neck cancers often results in collateral damage to adjacent salivary glands associated with clinically significant hyposalivation and xerostomia. Due to the reduced capacity of salivary glands to regenerate, hyposalivation is treated by substitution with artificial saliva, rather than through functional restoration of the glands. During embryogenesis, the ectodysplasin/ectodysplasin receptor (EDA/EDAR) signaling pathway is a critical element in the development and growth of salivary glands. We have assessed the effects of pharmacological activation of this pathway in a mouse model of radiation-induced salivary gland dysfunction. We report that post-irradiation administration of an EDAR-agonist monoclonal antibody (mAbEDAR1) normalizes function of radiation damaged adult salivary glands as determined by stimulated salivary flow rates. In addition, salivary gland structure and homeostasis is restored to pre-irradiation levels. These results suggest that transient activation of pathways involved in salivary gland development could facilitate regeneration and restoration of function following damage. PMID:25409170

  1. Pharmacological activation of the EDA/EDAR signaling pathway restores salivary gland function following radiation-induced damage.

    Directory of Open Access Journals (Sweden)

    Grace Hill

    Full Text Available Radiotherapy of head and neck cancers often results in collateral damage to adjacent salivary glands associated with clinically significant hyposalivation and xerostomia. Due to the reduced capacity of salivary glands to regenerate, hyposalivation is treated by substitution with artificial saliva, rather than through functional restoration of the glands. During embryogenesis, the ectodysplasin/ectodysplasin receptor (EDA/EDAR signaling pathway is a critical element in the development and growth of salivary glands. We have assessed the effects of pharmacological activation of this pathway in a mouse model of radiation-induced salivary gland dysfunction. We report that post-irradiation administration of an EDAR-agonist monoclonal antibody (mAbEDAR1 normalizes function of radiation damaged adult salivary glands as determined by stimulated salivary flow rates. In addition, salivary gland structure and homeostasis is restored to pre-irradiation levels. These results suggest that transient activation of pathways involved in salivary gland development could facilitate regeneration and restoration of function following damage.

  2. How much saliva is enough for avoidance of xerostomia?

    Science.gov (United States)

    Dawes, C

    2004-01-01

    Xerostomia, the subjective sensation of dry mouth, occurs when the salivary flow rate is less than the rate of fluid loss from the mouth by evaporation and by absorption of water through the oral mucosa. Evaporation can only occur during mouth-breathing but could reach a maximum rate of about 0.21 ml/min at rest, although normally it would be much less. Water absorption through the mucosa can occur because saliva has one sixth the osmotic pressure of extracellular fluid, thus creating a water gradient across the mucosa. The maximum absorption rate is calculated to be about 0.19 ml/min, declining to zero as the saliva reaches isotonicity. A recent study found the residual saliva volume, the volume of saliva left in the mouth after swallowing, to be 71% of normal in patients with severe hyposalivation and whose mouths felt very dry. Saliva in the residual volume is present as a thin film which varies in thickness with site. The hard palate has the thinnest film and when this is 0.1-0.3 ml/min may be necessary for this condition to be avoided. PMID:15153694

  3. Reservoir Complete Denture in a Patient with Xerostomia Secondary to Radiotherapy for Oral Carcinoma: A Case Report and Review of Literature

    OpenAIRE

    Ladda, R.; Kasat, VO; Gangadhar, SA; Baheti, S; Bhandari, AJ

    2014-01-01

    Xerostomia refers to a subjective sensation of dry mouth. A variety of factors can cause xerostomia including radiotherapy (RT) given for the treatment of oral carcinoma. Depending on the cause, treatment is provided to a patient suffering from xerostomia. In severe xerostomia salivary substitutes can be used and if the xerostomic patient is edentulous, then reservoir space for artificial salivary substitute can be created in partial as well as complete upper or lower dentures. The methods ad...

  4. Derivation of quantitative parameters from salivary scintigraphy and their utility in the diagnosis of xerostomia

    International Nuclear Information System (INIS)

    Full text: Xerostomia may be due to salivary dysfunction from a variety of causes and can be clinically variable ranging from halitosis to overt xerostomia. Semi-quantitative indices may be derived from salivary scintigraphy and may aid both clinical diagnosis and response to treatment. The objective of this study was to determine whether semi-quantitative indices were able to distinguish normal from abnormal salivary function and to be clinically useful. 56 consecutive patients with xerostomia (including a subset of 10 patients with clinical Sjogrens syndrome) and 25 healthy volunteers underwent salivary scintigraphy. Semi-quantitative analysis of time activity curves was performed deriving 6 different indices for each of the four major salivary glands. These indices included percent uptake (%UP), uptake ratios(UR),maximum accumulation (MA), pre-stimulatory oral radioactivity index (PRI), post-stimulatory oral radioactivity index (POI) and ejection fraction (EF). The 95% confidence interval around the mean values was used to compare normal volunteers and xerostomia patients. Wide reference limits were obtained for all indices derived from normal volunteers. No significant difference was found between normal volunteers and patients using any of the six indices. UR and EF showed the greatest difference between the groups. Allowing for Type Two (Beta) error, none of the above indices allow patients with xerostomia who have salivary dysfunction to be distinguished from normal subjects. Copyright (2002) The Australian and New Zealand Society of Nuclear Medicine Inc

  5. Clinical and dosimetric factors of radiation-induced esophageal injury: Radiation-induced esophageal toxicity

    Institute of Scientific and Technical Information of China (English)

    Wen-Bo Qiao; Yan-Hui Zhao; Yan-Bin Zhao; Rui-Zhi Wang

    2005-01-01

    AIM: To analyze the clinical and dosimetric predictive factors for radiation-induced esophageal injury in patients with non-small-cell lung cancer (NSCLC) during threedimensional conformal radiotherapy (3D-CRT). METHODS: We retrospectively analyzed 208 consecutive patients (146 men and 62 women) with NSCLC treated with 3D-CRT. The median age of the patients was 64 years (range 35-87 years). The clinical and treatment parameters including gender, age, performance status, sequential chemotherapy, concurrent chemotherapy, presence of carinal or subcarinal lymph nodes, pretreatment weight loss, mean dose to the entire esophagus, maximal point dose to the esophagus, and percentage of volume of esophagus receiving >55 Gy were studied. Clinical and dosimetric factors for radiation-induced acute and late grade 3-5 esophageal injury were analyzed according to Radiation Therapy Oncology Group (RTOG) criteria.RESULTS: Twenty-five (12%) of the two hundred and eight patients developed acute or late grade 3-5 esophageal injury. Among them, nine patients had both acute and late grade 3-5 esophageal injury, two died of late esophageal perforation. Concurrent chemotherapy and maximal point dose to the esophagus ≥60 Gy were significantly associated with the risk of grade 3-5 esophageal injury. Fifty-four (26%) of the two hundred and eight patients received concurrent chemotherapy. Among them, 25 (46%) developed grade 3-5 esophageal injury (P = 0.0001<0.01). However, nograde 3-5 esophageal injury occurred in patients who received a maximal point dose to the esophagus <60 Gy (P= 0.0001<0.01).CONCLUSION: Concurrent chemotherapy and the maximal esophageal point dose ≥60 Gy are significantly associated with the risk of grade 3-5 esophageal injury in patients with NSCLC treated with 3D-CRT.

  6. Perbedaan Laju Aliran Saliva yang Distimulasi dengan Mengunyah dan Menghisap Permen Karet Pada Pasien Mengonsumsi Antidepresan dengan Xerostomia Di RSUP Haji Adam Malik Medan

    OpenAIRE

    Dewi, Puput Roza

    2014-01-01

    Pasien yang mengonsumsi antidepresan akan merasakan xerostomia atau mulut kering sebagai salah satu efek samping dari obat tersebut. Xerostomia adalah sensasi subjektif dari kekeringan mulut, tetapi tidak selalu berhubungan dengan hipofungsi kelenjar saliva. Mengunyah atau menghisap permen karet xylitol merupakan salah satu cara alternatif menanggulangi xerostomia. Tujuan dari penelitian ini adalah mengetahui perbedaan laju aliran saliva yang distimulasi dengan mengunyah atau menghisap permen...

  7. Radiation induced oxidation for water remediation

    International Nuclear Information System (INIS)

    The action of ionizing radiation on halogenated hydrocarbons, in the presence and absence of ozone, was studied in water and wastewater. The combined ozone/electron-beam irradiation process was found especially suited for remediation of low-level contaminated groundwater. This combined treatment was often more effective than irradiation alone for wastewater decontamination. It reduced the COD without a simultaneous increase of BOD. Introduction of gaseous ozone directly into the irradiation chamber improved the water-flow turbulence, allowing treatment in layers thicker than the penetration range of the electrons, with increased decontamination efficiency. (author)

  8. Role of endothelium in radiation-induced normal tissue damages

    International Nuclear Information System (INIS)

    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)

  9. Radiation-induced camptocormia and dropped head syndrome. Review and case report of radiation-induced movement disorders

    International Nuclear Information System (INIS)

    In recent years, camptocormia and dropped head syndrome (DHS) have gained attention as particular forms of movement disorders. Camptocormia presents with involuntary forward flexion of the thoracolumbar spine that typically increases during walking or standing and may severely impede walking ability. DHS is characterized by weakness of the neck extensors and a consecutive inability to extend the neck; in severe cases the head is fixed in a ''chin to chest position.'' Many diseases may underlie these conditions, and there have been some reports about radiation-induced camptocormia and DHS. A PubMed search with the keywords ''camptocormia,'' ''dropped head syndrome,'' ''radiation-induced myopathy,'' ''radiation-induced neuropathy,'' and ''radiation-induced movement disorder'' was carried out to better characterize radiation-induced movement disorders and the radiation techniques involved. In addition, the case of a patient developing camptocormia 23 years after radiation therapy of a non-Hodgkin's lymphoma of the abdomen is described. In total, nine case series of radiation-induced DHS (n = 45 patients) and - including our case - three case reports (n = 3 patients) about radiogenic camptocormia were retrieved. Most cases (40/45 patients) occurred less than 15 years after radiotherapy involving extended fields for Hodgkin's disease. The use of wide radiation fields including many spinal segments with paraspinal muscles may lead to radiation-induced movement disorders. If paraspinal muscles and the thoracolumbar spine are involved, the clinical presentation can be that of camptocormia. DHS may result if there is involvement of the cervical spine. To prevent these disorders, sparing of the spine and paraspinal muscles is desirable. (orig.)

  10. Parotid gland shrinkage during IMRT predicts the time to Xerostomia resolution

    International Nuclear Information System (INIS)

    To assess the impact of mid-treatment parotid gland shrinkage on long term xerostomia during IMRT for oropharyngeal SCC. All patients treated with IMRT at a single Institution from November 2007 to June 2010 and undergoing weekly CT scans were selected. Parotid glands were contoured retrospectively on the mid treatment CT scan. For each parotid gland, the percent change relative to the planning volume was calculated and combined as weighted average. Patients were considered to be xerostomic if developed GR2+ dry mouth according to CTCAE v3.0. Predictors of the time to xerostomia resolution or downgrade to 1 were investigated at both uni- and multivariate analysis. 85 patients were selected. With a median follow up of 35.8 months (range: 2.4-62.6 months), the actuarial rate of xerostomia is 26.2% (SD: 5.3%) and 15.9% (SD: 5.3%) at 2 and 3 yrs, respectively. At multivariate analysis, mid-treatment shrink along with weighted average mean parotid dose at planning and body mass index are independent predictors of the time to xerostomia resolution. Patients were pooled in 4 groups based on median values of both mid-treatment shrink (cut-off: 19.6%) and mean WA parotid pl-D (cut-off: 35.7 Gy). Patients with a higher than median parotid dose at planning and who showed poor shrinkage at mid treatment are the ones with the outcome significantly worse (3-yr rate of xerostomia ≈ 50%) than the other three subgroups (3-yr rate of xerostomia ≈ 10%). For a given planned dose, patients whose parotids significantly shrink during IMRT are less likely to be long-term supplemental fluids dependent

  11. Fungiform papillae density in patients with burning mouth syndrome and xerostomia

    OpenAIRE

    Camacho-Alonso, Fabio; López-Jornet, Pía; Molino-Pagán, Diana

    2011-01-01

    Objective: The aim of this study was to analyze fungiform papillae density in patients with burning mouth syndrome (BMS) and xerostomia. Study design: In this cross-sectional clinical study, sixty patients were included (20 with BMS, 20 with xerostomia and 20 healthy controls). The fungiform papillae density was analyzed over a small region on the anterior tip of the tongue with the aid of a digital camera. The number of papillae was measured in an area of 19 mm2. Results: The patients with B...

  12. Radiation-Induced Cancer. Proceedings of a Symposium on Radiation-Induced Cancer

    International Nuclear Information System (INIS)

    The link between radiation and cancer was recognized soon after the discovery of X-rays and natural radioactivity. In the early years after the discovery of ionizing radiations some of the pioneering workers suffered severely from the damaging effects of radiation exposure. These incidents,- generally due to ignorance of the biological consequences of radiation exposure, were instrumental in starting investigations on the subject. Gradually precise information became available on the nature of radiation-induced damage and on the repair phenomena. This information has been advanced by recent progress in molecular biology, cellular biology, cytogenetics, biochemistry, virology, immunology and related disciplines. Contributions of these disciplines to radiation biology and cancer research has resulted in the use of radiation to solve various problems of human health including cancer. At the same time, with knowledge of the effects of radiations on cells and on various organisms including man, it has become possible to state the level of radiation dose that is not an apparent health hazard (i. e. the maximum permissible dose). This work has been vitally important in programs dealing with the occupational safety of personnel working with radiations. Although the present safety standards and devices are generally recognized as adequate, they must be re-evaluated from time to time in the light of the latest findings in radiobiology and other related disciplines. The Symposium on Radiation-Induced Cancer, organized by the International Atomic Energy Agency in collaboration with the World Health Organization, permitted discussion and evaluation of the present understanding of the nature of late biological effects of radiations including cancer, and development of protective as well as curative measures against cancer. Much attention was given to the comparative analysis of the effects of radiation, particularly at low dose levels, on man and experimental mammals. Emphasis

  13. Control of radiation-induced diarrhea with cholestyramine

    International Nuclear Information System (INIS)

    Cholestyramine is a non-absorbable ion-exchange resin which specifically binds bile salts. We have treated seven patients with acute or chronic radiation-induced diarrhea that was refractory to the usual methods of control with cholestyramine. In each case, the diarrhea was controlled with cholestyramine. This observation supports previous experimental work with animals which indicated that bile salts contribute to the genesis of radiation-induced diarrhea. Cholestyramine is well-tolerated, but should not be administered with certain oral medications. The results of this small series are preliminary, but point the way toward a more extensive clinical trial to define the usefulness of cholestyramine in the treatment of refractory acute or chronic radiation-induced diarrhea

  14. Mechanistic issues for modeling radiation-induced segregation

    International Nuclear Information System (INIS)

    Model calculations of radiation-induced chromium depletion and radiation-induced nickel enrichment at grain boundaries are compared to measured depletions and enrichments. The model is calibrated to fit chromium depletion in commercial purity 304 stainless steel irradiated in boiling water reactor (BWR) environments. Predicted chromium depletion profiles and the dose dependence of chromium concentration at grain boundaries are in accord with measured trends. Evaluation of chromium and nickel profiles in three neutron, and two ion, irradiation environments reveal significant inconsistencies between measurements and predictions

  15. Natural background as an indicator of radiation-induced cancer

    International Nuclear Information System (INIS)

    A review of the estimates for radiation-induced cancer rates is presented including the recent high estimates of 8 x 10-3 cancers/man rem. Also reviewed are the external background radiation and cancer incidence for the USA by state. A regression analysis of these data reveals a negative correlation between radiation dose and cancer rate, but only with a correlation coefficient of 0.39. However, the cancer induction rate of 8 x 10-3/man rem is shown to describe the observed data with a probability of 1 in 14,000. Thus such high estimates of radiation-induced cancer rate are highly improbable. (UK)

  16. Hedgehog signaling and radiation induced liver injury: a delicate balance.

    Science.gov (United States)

    Kabarriti, Rafi; Guha, Chandan

    2014-07-01

    Radiation-induced liver disease (RILD) is a major limitation of radiation therapy (RT) for the treatment of liver cancer. Emerging data indicate that hedgehog (Hh) signaling plays a central role in liver fibrosis and regeneration after liver injury. Here, we review the potential role of Hh signaling in RILD and propose the temporary use of Hh inhibition during liver RT to radiosensitize HCC tumor cells and inhibit their progression, while blocking the initiation of the radiation-induced fibrotic response in the surrounding normal liver. PMID:26202634

  17. Panretinal photocoagulation for radiation-induced ocular ischemia

    International Nuclear Information System (INIS)

    We present preliminary findings on the effectiveness of panretinal photocoagulation in preventing neovascular glaucoma in eyes with radiation-induced ocular ischemia. Our study group consisted of 20 patients who developed radiation-induced ocular ischemia following cobalt-60 plaque radiotherapy for a choroidal or ciliary body melanoma. Eleven of the 20 patients were treated by panretinal photocoagulation shortly after the diagnosis of ocular ischemia, but nine patients were left untreated. In this non-randomized study, the rate of development of neovascular glaucoma was significantly lower (p = 0.024) for the 11 photocoagulated patients than for the nine who were left untreated

  18. Timing of pilocarpine treatment during head and neck radiotherapy: concomitant administration reduces xerostomia better than post-radiation pilocarpine

    International Nuclear Information System (INIS)

    Purpose: To study whether oral pilocarpine administration during and three months after head and neck radiotherapy can prevent or reduce the expected post-radiation xerostomia. This regimen was compared to no treatment and to post-radiotherapy pilocarpine administration, which has previously been shown to reduce symptoms of xerostomia in several randomized trials. Methods: Xerostomia assessments were performed using a visual analog scale xerostomia questionnaire that measures oral dryness, oral comfort, difficulty with sleep, speech and eating. Higher scores indicate less xerostomia. All the patients had all major salivary glands in the initial field treated to ≥ 4,500 cGy. The concomitant pilocarpine group received 5 mg pilocarpine q.i.d. beginning on day one of radiotherapy and continuing for 3 months after completion of radiation. The control group had their baseline xerostomia measured prior to receiving pilocarpine. They subsequently took 5 mg pilocarpine t.i.d. for one month at which time they underwent a second xerostomia assessment. Xerostomia scores for each group were averaged and compared using the Student's t-test. Results: Seventeen patients who received pilocarpine during head and neck irradiation were compared to 12 post-radiotherapy patients who had not yet taken pilocarpine and the same patients after taking pilocarpine for one month. The mean intervals between completion of radiation and evaluation of xerostomia were 16 months for the control group and 17 months for the pilocarpine treated groups. The primary tumor sites treated as well as the total tumor doses were equivalent between the groups. Only one of the pilocarpine treated patients was still taking pilocarpine at the time of evaluation. Results are shown. For each component of xerostomia measured as well as the composite of all components, the group that had received pilocarpine during radiation had significantly less xerostomia than the no pilocarpine group (p<0.01 for each). Post

  19. Radiation induced crosslinking of cellulose ethers

    International Nuclear Information System (INIS)

    The effects of high-energy radiation on four ethers of cellulose: carboxymethyl (CMC); hydroxypropyl (HPC), hydroxyethyl (HEC) and methylcellulose (MC) were investigated. Polymers are irradiated in solid state and in aqueous solutions at various concentrations. Degree of substitution (DS) of the derivatives, the concentration of their aqueous solutions and irradiation conditions had a significant impact on the obtained products. Irradiation of polymers in solid state and in diluted aqueous solutions resulted in their degradation. However, it was found that for concentrated solutions gel formation occurred. Paste-like form of the initial material, when water plasticizes the bulk of polymer as well as the high dose rate, what prevents oxygen penetration of the polymer during irradiation, have been found favourable for hydrogel formation. Up to 95% of gel fraction was obtained from solutions of CMC with concentration over 50% irradiated by γ-rays or electron beam. It was pointed out that the ability to the formation of the three-dimensional network is related to the DS of anhydroglucose units and a type of chemical group introduced to main chain of cellulose. Produced hydrogels swelled markedly in water. Despite of the crosslinked structure they underwent degradation by the action of cellulase enzyme or microorganisms from compost, and can be included into the group of biodegradable materials. (author)

  20. Synchrotron-Radiation Induced X-Ray Emission (SRIXE)

    Energy Technology Data Exchange (ETDEWEB)

    Jones, Keith W.

    1999-09-01

    and increase in scientific use can be maintained for the synchrotron x-ray source. A short summary of the present state of the synchrotron radiation-induced x-ray emission (SRIXE) method is presented here. Basically, SRIXE experiments can include any that depend on the detection. of characteristic x-rays produced by the incident x-ray beam born the synchrotron source as they interact with a sample. Thus, experiments done to measure elemental composition, chemical state, crystal, structure, and other sample parameters can be considered in a discussion of SRIXE. It is also clear that the experimentalist may well wish to use a variety of complementary techniques for study of a given sample. For this reason, discussion of computed microtomography (CMT) and x-ray diffraction is included here. It is hoped that this present discussion will serve as a succinct introduction to the basic ideas of SRIXE for those not working in the field and possibly help to stimulate new types of work by those starting in the field as well as by experienced practitioners of the art. The topics covered include short descriptions of (1) the properties of synchrotron radiation, (2) a description of facilities used for its production, (3) collimated microprobe, (4) focused microprobes, (5) continuum and monoenergetic excitation, (6) detection limits, (7) quantitation, (8) applications of SRIXE, (9) computed microtomography (CMT), and (10)chemical speciation using x-ray absorption near-edge structure (XANES) and extended x-ray absorption fine structure (EXAFS). An effort has been made to cite a wide variety of work from different laboratories to show the vital nature of the field.

  1. The effects of low-level laser therapy on xerostomia (mouth dryness

    Directory of Open Access Journals (Sweden)

    Pavlić Verica

    2012-01-01

    Full Text Available Introduction. Xerostomia is a subjective complaint of mouth/oral dryness, caused by a reduction in normal salivary secretion due to different causes. Even though there are many available treatment modalities to enhance salivary flow, the therapy often remains unsatisfactory. The low-level laser therapy (low-level laser irradiation, photo-biomodulation has been extensively used as a new, non-invasive approach and advantageous tool for reduction of xerostomia. Therefore, the aim of this study is to give a systematic overview on the effects of low-level laser therapy on xerostomia. Material and Methods. A systematic review of published articles in PubMed database was carried out using keywords: ”low-level laser therapy”, ”xerostomia”, ”mouth dryness”. Results. In all published articles, which were considered adequate for this overview, positive effects of low-level laser therapy were reported. Low-level laser therapy could significantly enhance salivary secretion and improve antimicrobial characteristics of secreted saliva (increased level of secretory immunoglobulin A; sIgA. Furthermore, low-level laser therapy could improve salivary flow and regeneration of salivary duct epithelial cells. Conclusion. The current literature suggests that low-level laser therapy can be safely and effectively used as an advanced treatment modality for reduction of xerostomia. Further in vivo, in vitro and clinical studies using different irradiation parameters are suggested to determine the best laser parameters to be used.

  2. The management of xerostomia in patients on haemodialysis : comparison of artificial saliva and chewing gum

    NARCIS (Netherlands)

    Bots, CP; Brand, HS; Veerman, ECI; Valentijn-Benz, M; Van Amerongen, BM; Amerongen, AVN; Valentijn, RM; Vos, PI; Bijlsma, JA; ter Wee, PM

    2005-01-01

    Many patients on haemodialysis (HD) therapy suffer from a dry mouth and xerostomia. This can be relieved by mechanical and gustatory stimulation or palliative care. The aim of this crossover study was to investigate the effect and preferences of a sugar-free chewing gum (Freedent White(TM)) and a xa

  3. A systematic review of salivary gland hypofunction and xerostomia induced by cancer therapies

    DEFF Research Database (Denmark)

    Jensen, S.B.; Pedersen, A.M.L.; Vissink, A.;

    2010-01-01

    This systematic review aimed to assess the literature for prevalence, severity, and impact on quality of life of salivary gland hypofunction and xerostomia induced by cancer therapies. The electronic databases of MEDLINE/PubMed and EMBASE were searched for articles published in English since the ...

  4. Prevalence of xerostomia on type 2 diabetes mellitus in Hajj Hospital Surabaya

    Directory of Open Access Journals (Sweden)

    Kus Harijanti

    2007-09-01

    Full Text Available Diabetes Mellitus (DM is a chronic disorder of carbohydrate, fat and protein metabolism. A defective or deficient of the insulin secretory, which is translated into impaired carbohydrate (glucose use, is characteristic feature of DM, as the resultant is hyperglycemia. There is variability among patients, however, morphologic changes are likely found in arteries (atherosclerosis, basement membrane of the blood vessel wall tissues (micro angiopathy, kidneys (diabetic nephropathy, retina (retinopathy, nerves (neuropathy and other tissues. If it involves salivary glands, the clinical sign is xerostomia. The type 2 of DM is caused by a combination of peripheral resistance to insulin action and an inadequate secretory response of the pancreatic b-cell. Approximately 80% to 90% of patients have type 2 diabetes. The purpose of this study was to determine the prevalence of xerostomia and its relation with level of blood glucose in type 2 DM. The data was taken using cross sectional method on the diabetic patients of Internal Medicine clinic, Hajj Hospital Surabaya from February to March 2006. The result that showed among 50 samples of the type 2 DM, the prevalence of xerostomia were 38 patients (76%. Most of the patients (32 patients = 84% on bad regulation of DM with level of fasting glucose ≥ 126 mg/dl and level of post prandial glucose ≥ 180 mg/dl. The study showed that bad regulation of type 2 DM could develop complication on salivary glands, with xerostomia as the clinical sign.

  5. Seven cases of radiation-induced cutaneous squamous cell carcinoma

    International Nuclear Information System (INIS)

    We report 7 cases of radiation-induced skin cancer. The diagnosis was based on the history of radiotherapy for benign skin diseases (5 cases) and of occupational exposures to medical doctors (2 cases). All cases were squamous cell carcinomas which arose from chronic radiodermatitis. The estimated latent period of these tumors ranged from 6 to 64 years, with an average of 29.9 years. After surgical treatments of the lesions, no local recurrences were observed in all cases. Benign skin diseases had sometimes been treated with low-energy radiation before the 1960s. Considering the estimated latent period, the peak time point of developing risk of radiation-induced skin cancer by such treatment has been already passed, however, the danger of it should not be ignored in future. In association with multiplicity of radiation usage, occupational exposure of radiation may develop the risk of occurrence of skin cancer in future. Therefore, we should recognize that radiation-induced skin cancer is not in the past. In the cases of chronic skin diseases showing warty keratotic growth, erosion and ulcer, we should include chronic radio-dermatitis in the differential diagnosis. It is necessary to recall all patients about the history of radiotherapy or radiation exposure. Rapid histopathological examination is mandatory because of the suspicion of radiation-induced skin cancer. (author)

  6. Preparation of polymer microspheres by radiation-induced polymerization

    International Nuclear Information System (INIS)

    Cross-liking monomer, diethylene glycol dimethacrylate gives microspheres from organic solution by radiation-induced polymerization. /One of the remarkable result is that the number of the microspheres is not changing during the polymerization. Ethyl methacrylate, maleic anhydride, styrene and acrylamide are used as comonomers. These comonomers give the microspheres in the range of 0 to 0.4 as mol fractions. (author)

  7. Poor outcome in radiation-induced constrictive pericarditis

    Energy Technology Data Exchange (ETDEWEB)

    Karram, T.; Rinkevitch, D.; Markiewicz, W. (Technion Medical School, Haifa (Israel))

    1993-01-15

    The purpose was to compare the outcome of patients with radiation-induced constrictive pericarditis versus patients with constiction due to another etiology. Twenty patients with constrictive pericarditis were seen during 1975-1986 at a single medical center. Six had radiation-induced constrictive pericarditis (Group A). The etiology was idiopathic in ten subjects and secondary to carcinomatous encasement, chronic renal failure, purulent infection and tuberculosis in one patient each (Group B, N = 14). Meang age was 53.4 [+-] 15.5 years. Extensive pericardiectomy was performed in 3/6 Group A and 13/14 Group B patients. All Group A patients died, 4 weeks - 11 years post-diagnosis (median = 10 months). Two Group A patients died suddenly, one died post-operatively of respiratory failure, another of pneumonia and two of recurrent carcinoma. Thirteen Group B patients are alive (median follow-up = 72 months). The only death in this group was due to metastatic cancer. The poor outcome with radiation-induced constriction is probably multi-factorial. Poor surgical outcome is to be expected in patients with evidence of recurrent tumor, high-dose irradiation, pulmonary fibrosis or associated radiation-induced myocardinal, valvular or coronary damage.

  8. Report of board IV: Radiation damages and radiation induced diseases

    International Nuclear Information System (INIS)

    Board IV (radiation damage and radiation-induced diseases) worked on the effects of ionizing radiation on living organisms and studies the radiation damage it entailed. Investigations with cells or model systems serve to recognize certain causal relationships in an organism out of the diversity of reactions encountered. (orig./AK)

  9. Prevention of radiation induced taste aversion in rats

    International Nuclear Information System (INIS)

    Diltiazem, a calcium channel blocker, and a cardiovascular therapeutic agent offers significant protection to mice against lethal dose of ionizing radiation. Considering the potential efficacy of diltiazem as a radioprotector for human use, it was deemed necessary to investigate its influence on radiation-induced behavioural changes like nausea, vomiting, learning, memory and performance. In the present studies, conditioned taste aversion (CTA) test based on consumption of saccharin solution, was used as a marker of behavioural changes. Significant CTA (97±2%) was observed in rats irradiated with 60Co gamma rays (absorbed dose 1 Gy). Administration of diltiazem at doses greater than 10 mg/kg, body wt, evoked CTA in a dose-dependent manner and that was found to be further aggravated on irradiation. At a lower dose of 5 mg/kg, body wt, diltiazem did not evoke CTA and protected against radiation induced aversion significantly (62±3%). The results suggest that diltiazem at concentrations lower than 10 mg/kg, body wt, in rats may be useful in preventing radiation induced behavioural changes. This observation could be of particular significance in clinical radiotherapy where radiation induced nausea and vomiting are of great concern. (author)

  10. Use of probiotics for prevention of radiation-induced diarrhea

    Institute of Scientific and Technical Information of China (English)

    P Delia; G Sansotta; V Donate; P Frosina; G Messina; C De Renzis; G Famularo

    2007-01-01

    AIM: To investigate the efficacy of a high-potency probiotic preparation on prevention of radiation-induced diarrhea in cancer patients.METHODS: This was a double-blind, placebo-controlled trial. Four hundred and ninety patients who underwent adjuvant postoperative radiation therapy after surgery for sigmoid, rectal, or cervical cancer were assigned to either the high-potency probiotic preparation VSL#3 (one sachet t.i.d.,) or placebo starting from the first day of radiation therapy. Efficacy endpoints were incidence and severity of radiation-induced diarrhea, daily number of bowel movements, and the time from the start of the study to the use of loperamide as rescue medication.RESULTS: More placebo patients had radiation-induced diarrhea than VSL#3 patients (124 of 239 patients, 51.8%, and 77 of 243 patients, 31.6%; P < 0.001) and more patients given placebo suffered grade 3 or 4 diarrhea compared with VSL#3 recipients (55.4% and 1.4%, P < 0.001). Daily bowel movements were 14.7 ± 6 and 5.1 ± 3 among placebo and VSL#3 recipients (P < 0.05), and the mean time to the use of loperamide was 86 ± 6 h for placebo patients and 122 ± 8 h for VSL#3 patients (P < 0.001).CONCLUSION: Probiotic lactic acid-producing bacteria are an easy, safe, and feasible approach to protect cancer patients against the risk of radiation-induced diarrhea.

  11. Importance of the initial volume of parotid glands in xerostomia for patients with head and neck cancers treated with IMRT

    International Nuclear Information System (INIS)

    Our aim was to evaluate predictors of xerostomia in patients with head and neck cancers treated with intensity-modulated radiation therapy (IMRT). Thirty-three patients with pharyngeal cancer were evaluated for xerostomia after having been treated with IMRT. All patients were treated with whole-neck irradiation of 46-50 Gy by IMRT, followed by boost IMRT to the high-risk clinical target volume to a total dose of 56-70 Gy in 28-35 fractions (median, 68 Gy). For boost IMRT, a second computed tomography (CT-2) scan was done in the third to fourth week of IMRT. Xerostomia was scored 3-4 months after the start of IMRT. The mean doses to the contralateral and ipsilateral parotid glands were 24.0±6.2 and 30.3±6.6 Gy, respectively. Among the 33 patients, xerostomia of grades 0, 1, 2 and 3 was noted in one, 18, 12 and two patients, respectively. Although the mean dose to the parotid glands was not correlated with the grade of xerostomia, the initial volume of the parotid glands was correlated with the grade of xerostomia (P=0.04). Of 17 patients with small parotid glands (≤38.8 ml) on initial CT (CT-1), 11 (65%) showed grade 2 or grade 3 xerostomia, whereas only three (19%) of 16 patients with larger parotid glands showed grade 2 xerostomia (P<0.05). The mean volume of the parotid glands on CT-1 was 43.1±15.2 ml, but decreased significantly to 32.0±11.4 ml (74%) on CT-2 (P<0.0001). Initial volumes of the parotid glands are significantly correlated with the grade of xerostomia in patients treated with IMRT. The volume of the parotid glands decreased significantly during the course of IMRT. (author)

  12. Application of controlled radiation-induced degradation in polymers: less exploited aspect of radiation processing of polymers

    International Nuclear Information System (INIS)

    Industrial use of ionizing radiation treatment has been most successful in applications related to polymeric materials. The polymer, plastics and rubber industries have benefited from the unique advantages of ionizing radiation since its inception as an industrial tool to modify their properties and manufacture novel materials with value addition to the end product. The established and emerging applications of electron beam processing of polymers are based on the well known ultimate effects of ionizing radiation on polymers namely, crosslinking, curing, grafting and chain scissioning. Radiation-induced crosslinking dominates most applications, whereas the chain scissioning effect is much less explored and currently limited to radiation-induced degradation of Teflon, cellulose and polypropylene. The controlling of radiation-induced degradation for achieving a target average molecular weight or distribution has been evaluated for some polysaccharides, biopolymers and waste inner tubes whereas mitigation of the degradative effects of radiation has been analyzed from the point of view of using certain stabilizers, copolymers and annealing at an appropriate temperature. Several new or highly specialized techniques such as positron annihilation lifetime spectroscopy. Rutherford backscattering, elastic recoil detection analysis and solid waste NMR spectroscopy and gas chromatography-mass spectroscopy have been applied to the study or radiation-induced degradation. New information has been collected on the morphological changes associated with radiation-induced degradation processes, including chain scission, oxidation and free volume alteration. The IAEA coordinated research project (CRP) on Controlling of Degradation Effects in Radiation Processing of Polymers dealt with the role and importance of using ionizing radiation in controlling properties of natural and synthetic polymers through its degradative effect. This paper provides a summary of most important results

  13. Cost-effectiveness landscape analysis of treatments addressing xerostomia in patients receiving head and neck radiation therapy

    OpenAIRE

    Sasportas, Laura S.; Hosford, Andrew T.; Sodini, Maria A.; Waters, Dale J.; Zambricki, Elizabeth A.; Joëlle K Barral; Graves, Edward E.; Brinton, Todd J.; Yock, Paul G.; Le, Quynh-Thu; Sirjani, Davud

    2013-01-01

    Head and neck (H&N) radiation therapy (RT) can induce irreversible damage to the salivary glands thereby causing long-term xerostomia or dry mouth in 68%–85% of the patients. Not only does xerostomia significantly impair patients’ quality-of-life (QOL) but it also has important medical sequelae, incurring high medical and dental costs. In this article, we review various measures to assess xerostomia and evaluate current and emerging solutions to address this condition in H&N cancer patients. ...

  14. Radiation-induced refraction artifacts in the optical CT readout of polymer gel dosimeters

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, Warren G.; Jirasek, Andrew, E-mail: jirasek@uvic.ca [Department of Physics and Astronomy, University of Victoria, Victoria, British Columbia V8P 5C2 (Canada); Wells, Derek M. [British Columbia Cancer Agency, Vancouver Island Centre, Victoria, British Columbia V8R 6V5 (Canada)

    2014-11-01

    Purpose: The objective of this work is to demonstrate imaging artifacts that can occur during the optical computed tomography (CT) scanning of polymer gel dosimeters due to radiation-induced refractive index (RI) changes in polyacrylamide gels. Methods: A 1 L cylindrical polyacrylamide gel dosimeter was irradiated with 3 × 3 cm{sup 2} square beams of 6 MV photons. A prototype fan-beam optical CT scanner was used to image the dosimeter. Investigative optical CT scans were performed to examine two types of rayline bending: (i) bending within the plane of the fan-beam and (ii) bending out the plane of the fan-beam. To address structured errors, an iterative Savitzky–Golay (ISG) filtering routine was designed to filter 2D projections in sinogram space. For comparison, 2D projections were alternatively filtered using an adaptive-mean (AM) filter. Results: In-plane rayline bending was most notably observed in optical CT projections where rays of the fan-beam confronted a sustained dose gradient that was perpendicular to their trajectory but within the fan-beam plane. These errors caused distinct streaking artifacts in image reconstructions due to the refraction of higher intensity rays toward more opaque regions of the dosimeter. Out-of-plane rayline bending was observed in slices of the dosimeter that featured dose gradients perpendicular to the plane of the fan-beam. These errors caused widespread, severe overestimations of dose in image reconstructions due to the higher-than-actual opacity that is perceived by the scanner when light is bent off of the detector array. The ISG filtering routine outperformed AM filtering for both in-plane and out-of-plane rayline errors caused by radiation-induced RI changes. For in-plane rayline errors, streaks in an irradiated region (>7 Gy) were as high as 49% for unfiltered data, 14% for AM, and 6% for ISG. For out-of-plane rayline errors, overestimations of dose in a low-dose region (∼50 cGy) were as high as 13 Gy for

  15. Radiation-induced camptocormia and dropped head syndrome. Review and case report of radiation-induced movement disorders

    Energy Technology Data Exchange (ETDEWEB)

    Seidel, Clemens; Kuhnt, Thomas; Kortmann, Rolf-Dieter; Hering, Kathrin [Leipzig University, Department of Radiotherapy and Radiation Oncology, Leipzig (Germany)

    2015-10-15

    In recent years, camptocormia and dropped head syndrome (DHS) have gained attention as particular forms of movement disorders. Camptocormia presents with involuntary forward flexion of the thoracolumbar spine that typically increases during walking or standing and may severely impede walking ability. DHS is characterized by weakness of the neck extensors and a consecutive inability to extend the neck; in severe cases the head is fixed in a ''chin to chest position.'' Many diseases may underlie these conditions, and there have been some reports about radiation-induced camptocormia and DHS. A PubMed search with the keywords ''camptocormia,'' ''dropped head syndrome,'' ''radiation-induced myopathy,'' ''radiation-induced neuropathy,'' and ''radiation-induced movement disorder'' was carried out to better characterize radiation-induced movement disorders and the radiation techniques involved. In addition, the case of a patient developing camptocormia 23 years after radiation therapy of a non-Hodgkin's lymphoma of the abdomen is described. In total, nine case series of radiation-induced DHS (n = 45 patients) and - including our case - three case reports (n = 3 patients) about radiogenic camptocormia were retrieved. Most cases (40/45 patients) occurred less than 15 years after radiotherapy involving extended fields for Hodgkin's disease. The use of wide radiation fields including many spinal segments with paraspinal muscles may lead to radiation-induced movement disorders. If paraspinal muscles and the thoracolumbar spine are involved, the clinical presentation can be that of camptocormia. DHS may result if there is involvement of the cervical spine. To prevent these disorders, sparing of the spine and paraspinal muscles is desirable. (orig.) [German] In den letzten Jahren haben Bewegungsstoerungen von Wirbelsaeule und paraspinaler Muskulatur in

  16. A study of radiation-induced cerebral vascular injury in nasopharyngeal carcinoma patients with radiation-induced temporal lobe necrosis.

    Directory of Open Access Journals (Sweden)

    Jianhong Ye

    Full Text Available PURPOSE: To investigate radiation-induced carotid and cerebral vascular injury and its relationship with radiation-induced temporal lobe necrosis in nasopharyngeal carcinoma (NPC patients. METHODS AND MATERIALS: Fifty eight NPC patients with radiation-induced temporal lobe necrosis (TLN were recruited in the study. Duplex ultrasonography was used to scan bilateral carotid arterials to evaluate the intima-media thickness (IMT and occurrence of plaque formation. Flow velocities of bilateral middle cerebral arteries (MCAs, internal carotid arteries (ICAs and basal artery (BA were estimated through Transcranial Color Doppler (TCD. The results were compared with data from 33 patients who were free from radiation-induced temporal lobe necrosis after radiotherapy and 29 healthy individuals. RESULTS: Significant differences in IMT, occurrence of plaques of ICAs and flow velocities of both MCAs and ICAs were found between patients after radiotherapy and healthy individuals (p<0.05. IMT had positive correlation with post radiation interval (p = 0.049. Compared with results from patients without radiation-induced TLN, the mean IMT was significantly thicker in patients with TLN (p<0.001. Plaques were more common in patients with TLN than patients without TLN (p = 0.038. In addition, flow velocities of MCAs and ICAs in patients with TLN were much faster (p<0.001, p<0.001. Among patients with unilateral TLN, flow velocity of MCAs was significantly different between ipsilateral and contralateral sides to the lesion (p = 0.001. CONCLUSION: Thickening of IMT, occurrence of plaque formation and hemodynamic abnormality are more common in patients after radiotherapy, especially in those with TLN, compared with healthy individuals.

  17. Clinical evaluation of the intraoral fluoride releasing system in radiation-induced xerostomic subjects. Part 2: Phase I study.

    Science.gov (United States)

    Chambers, Mark S; Mellberg, James R; Keene, Harris J; Bouwsma, Otis J; Garden, Adam S; Sipos, Tibor; Fleming, Terence J

    2006-10-01

    Radiation-induced xerostomia can result in the rapid onset and progression of dental caries in head and neck cancer patients. Topically applied fluorides have been successfully used to inhibit the formation of dental caries in this population. However, because intensive daily self-application is required, compliance is an issue. The intraoral fluoride-releasing system (IFRS) containing a sodium fluoride core is a newly developed, sustained-release, passive drug delivery system that does not require patient involvement except for periodic replacement, thus reducing the effect of patient compliance on its effectiveness in dental caries prevention. Twenty-two head and neck cancer patients from U. T. M. D. Anderson Cancer Center, with radiation-induced xerostomia, were entered into a pilot study to contrast the daily home use of a 0.4% stannous fluoride-gel-containing tray (control group) to IFRS (study group) with respect to tolerability and adherence, and to obtain information on relative caries preventive efficacy. Participants were stratified on the basis of radiation exposure and randomly assigned to treatment with either IFRS or stannous fluoride gel. Patients in both groups were fitted with two IFRS retainers and also were instructed to use a 1100-ppm fluoride conventional sodium fluoride dentifrice twice daily. The study was conducted as a single-blinded, parallel-cell trial. Pre-existing carious lesions were restored prior to the beginning of the study. The efficacy variable was determined by the mean number of new or recurrent decayed surfaces. Patients were examined for caries 4, 8, 12, 24, 36, and 48 weeks after initiation of treatment. Reports of adverse reactions were based on information volunteered by patients and that were elicited during interviews. At baseline, the resting and stimulated salivary flow rates (g/5min) were significantly greater in the control group than in the study group (pIFRS groups during the study period. The rate of new or

  18. Radiation-induced crosslinking and post-processing of poly(L-lactic acid) composite

    International Nuclear Information System (INIS)

    Poly(L-lactic acid), PLLA, was irradiated using electron beams (EBs) in the presence of triallyl isocyanurate (TAIC) at 5% concentration as crosslinking agent. The crosslinked PLLA obtained has heat resistance, as demonstrated by retention of its original shape at glass transition temperature or even higher than 200 oC. As an application of this fact, crosslinked PLLA is applied in spectacle lens to prevent shape deformation of eyeglass frames in displaying and transporting. However, in this application to lens, it is not enough to improve the thermal deformation of PLLA under stress at 70 oC. Radiation-induced crosslinking of a PLLA/silicon dioxide (SiO2) composite with TAIC and post-processing of the crosslinked PLLA composite by heating were further investigated from the viewpoint of thermal deformation. The PLLA materials have several advantages such as high heat resistance and transparency. It is therefore proved that the combination of radiation-induced crosslinking, composition of SiO2 and post-heating is beneficial for expanding the applications of PLLA.

  19. Radiation-induced crosslinking and post-processing of poly(L-lactic acid) composite

    Energy Technology Data Exchange (ETDEWEB)

    Nagasawa, Naotsugu, E-mail: nagasawa.naotsugu@jaea.go.j [Japan Atomic Energy Agency (JAEA), Quantum Beam Science Directorate, 1233 Watanuki, Takasaki, Gunma 370-1292 (Japan); Kasai, Noboru; Yagi, Toshiaki; Yoshii, Fumio; Tamada, Masao [Japan Atomic Energy Agency (JAEA), Quantum Beam Science Directorate, 1233 Watanuki, Takasaki, Gunma 370-1292 (Japan)

    2011-02-15

    Poly(L-lactic acid), PLLA, was irradiated using electron beams (EBs) in the presence of triallyl isocyanurate (TAIC) at 5% concentration as crosslinking agent. The crosslinked PLLA obtained has heat resistance, as demonstrated by retention of its original shape at glass transition temperature or even higher than 200 {sup o}C. As an application of this fact, crosslinked PLLA is applied in spectacle lens to prevent shape deformation of eyeglass frames in displaying and transporting. However, in this application to lens, it is not enough to improve the thermal deformation of PLLA under stress at 70 {sup o}C. Radiation-induced crosslinking of a PLLA/silicon dioxide (SiO{sub 2}) composite with TAIC and post-processing of the crosslinked PLLA composite by heating were further investigated from the viewpoint of thermal deformation. The PLLA materials have several advantages such as high heat resistance and transparency. It is therefore proved that the combination of radiation-induced crosslinking, composition of SiO{sub 2} and post-heating is beneficial for expanding the applications of PLLA.

  20. Effect of Epicatechin against Radiation-Induced Oral Mucositis: In Vitro and In Vivo Study

    OpenAIRE

    Shin, Yoo Seob; Shin, Hyang Ae; Kang, Sung Un; Kim, Jang Hee; Oh, Young-Taek; Park, Keun Hyung; Kim, Chul-Ho

    2013-01-01

    Purpose Radiation-induced oral mucositis limits the delivery of high-dose radiation to head and neck cancer. This study investigated the effectiveness of epicatechin (EC), a component of green tea extracts, on radiation-induced oral mucositis in vitro and in vivo. Experimental Design The effect of EC on radiation-induced cytotoxicity was analyzed in the human keratinocyte line HaCaT. Radiation-induced apoptosis, change in mitochondrial membrane potential (MMP), reactive oxygen species (ROS) g...

  1. The progress in research on the mechanism, prevention and treatment of radiation-induced lung injury

    International Nuclear Information System (INIS)

    During radiotherapy of chest tumor,many patients often develop radiation-induced lung injury (including radiation induced interstitial pneumonia or pulmonary fibrosis), which significantly affects their quality of life. Therefore, it is very important to study the mechanism, prevention, and treatment of radiation-induced lung injury. Herein a review of recent research advances in radiation-induced lung injury is made, in order to provide theoretical basis for further research. (authors)

  2. Clinical management of salivary gland hypofunction and xerostomia in head and neck cancer patients: successes and barriers*

    OpenAIRE

    Vissink, Arjan; James B. Mitchell; Baum, Bruce J.; Kirsten H Limesand; Jensen, Siri Beier; Fox, Philip C.; Elting, Linda S.; Langendijk, Johannes A; Coppes, Robert P.; Reyland, Mary E.

    2010-01-01

    The most significant long-term complication of radiotherapy in the head and neck region is hyposalivation and its related complaints, particularily xerostomia. This paper addresses the pathophysiology underlying irradiation damage to salivary gland tissue, the consequences of radiation injury, and issues contributing to the clinical management of salivary gland hypofunction and xerostomia. These include ways to: (1) prevent or minimize radiation injury of salivary gland tissue, (2) manage rad...

  3. Radiation induced graft copolymerization of acrylamide onto poly (3-hydroxybutyrate)

    International Nuclear Information System (INIS)

    The graft copolymer poly (3-hydroxybutyrate)-g- polyacrylamide [P (HB-g-AAm)] was synthesized by radiation induced graft copolymerization of acrylamide onto poly (3-hydroxybutyrate). The study was conducted by the simultaneous irradiation method. The structure of [P (HB-g-AAm)] was identified by Fourier Transform Infrared (FTIR) spectroscopy. Thermal behavior of the graft copolymer was also studied by Thermal Gravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC). From the results it was found that FTIR studies showed new signals (stretching -N-H) as strong evidence of grafting. The grafting degree was found to be 10 % and the thermodynamic parameter obtained from the DSC thermogram of plain PHB and the graft copolymer varied showing decrease in the material crystallinity and increase in the glass transition temperature. These results demonstrate that the radiation induced graft copolymerization reaction of acrylamide onto PHB was successively achieved. (Author)

  4. Caffeine Markedly Enhanced Radiation-Induced Bystander Effects

    Institute of Scientific and Technical Information of China (English)

    JIANG Erkang; WU Lijun

    2009-01-01

    A bstract In this paper it is shown that incubation with 2 mM caffeine enhanced significantly the MN (micronucleus) formation in both the 1 cGy a-particle irradiated and non-irradiated by- stander regions. Moreover, caffeine treatment made the non-irradiated bystander cells more sensi- tive to damage signals. Treated by c-PTIO(2-(4-carboxy-phenyl)-4,4,5,5-tetramethyl-imidazoline- 1-oxyl-3-oxide), a nitric oxide (NO) scavenger, the MN frequencies were effectively inhibited, showing that nitric oxide might be very important in mediating the enhanced damage. These results indicated that caffeine enhanced the low dose a-particle radiation-induced damage in ir- radiated and non-irradiated bystander regions, and therefore it is important to investigate the relationship between the radiosensitizer and radiation-induced bystander effects (RIBE).

  5. Depleted uranium and radiation - induced lung cancer and leukaemia

    International Nuclear Information System (INIS)

    Reports of leukaemias and other cancers among servicemen who took part in the 1991 Gulf war or in the more recent operations in the Balkans are of continuing interest, as is the possibility, however slight, that depleted uranium (DU) is one of the causative factors. This commentary includes the results of a UK epidemiological study on the mortality of Gulf war veterans and , although not containing information on DU exposure, gives data on overall levels of mortality and therefore carries more weight than anecdotal reports. Also included are brief summaries on radiation-induced lung cancer in uranium workers as well as radiation-induced leukaemia in Japanese atomic bomb survivors and patients ankylosing spondylitis treated using x-rays. This commentary concludes with a critique of Iraqi cancer statistics as well as giving information on environmental contamination in Kosovo and the use of DU ammunition. (author)

  6. Action of liposomal superoxide dismutase on measurable radiation - induced fibroses

    International Nuclear Information System (INIS)

    Radiation-induced fibroses are a classical complication of radiotherapy. The effect of liposomal superoxide dismutase (Lipsod) on 45 radiation-induced fibroses of measurable volume and hardness in 34 patients was studied Over 3 weeks, 6 injections of Lipsod were given intramuscularly: 5 mg for 28 patients and 2 mg for 6 patients. On the average, the volume decreased by 32%. A marked or moderate softening was observed in 80% of the fibroses; it was accompanied by functional improvement in 75% of the patients (in cases of preexisting difficulties). The effectiveness was independent of the time lag between the Lipsod treatment and irradiation. The decreases noted in the volume and hardness of the fibroses remained stable during a follow up of 5-24 months. This systematic study shows the interest of Lipsod treatment of quasi-experimental fibroses where no other effective therapy exists

  7. Radiation-induced hemorrhagic duodenitis associated with sorafenib treatment.

    Science.gov (United States)

    Yanai, Shunichi; Nakamura, Shotaro; Ooho, Aritsune; Nakamura, Shigeo; Esaki, Motohiro; Azuma, Koichi; Kitazono, Takanari; Matsumoto, Takayuki

    2015-06-01

    Sorafenib, an oral inhibitor of multiple tyrosine kinase receptors, has been widely used as a standard medical treatment for advanced hepatocellular carcinoma (HCC). Here, we report a 66-year-old male patient who developed gastrointestinal bleeding due to radiation-induced hemorrhagic duodenitis associated with sorafenib treatment. We started oral administration of sorafenib because of the recurrence of HCC with lung metastases. The patient had been treated by radiotherapy for para-aortic lymph node metastases from HCC 4 months before the bleeding. Esophagogastroduodenoscopy (EGD) revealed edematous reddish mucosa with friability and telangiectasia in the second portion of the duodenum. Computed tomography and capsule endoscopy revealed that the hemorrhagic lesions were located in the distal duodenum. After discontinuation of sorafenib, the bleeding disappeared and a follow-up EGD confirmed improvement of duodenitis. Based on these findings, the diagnosis of radiation-induced hemorrhagic duodenitis associated with sorafenib was made. PMID:25832768

  8. Radiation-induced apoptosis in thymocytes: pH sensitization

    International Nuclear Information System (INIS)

    Thymocytes were used as a model system to study the effect of microenvironmental pH changes on the radiation-induced apoptosis. We found that the sensitivity of thymocytes toward radiation induced apoptosis is increased by increasing the pH of the incubation medium. The major sensitivity change occurs between pH 7 and 8. In a given cell suspension the results obtained were similar when the apoptosis evaluation was carried out either by counting the picnotic nuclei, or monitoring the fraction of apoptic nuclei by flow cytometry; both methods show a radiosensitization when the pH value of incubation media rises from 7 to 8. These results may be important when 'in vitro' experiments are performed with lymphoid cells, since changes in pH of the media may determine important changes in the results. (orig.)

  9. A case of radiation-induced cancer of the hypopharynx

    Energy Technology Data Exchange (ETDEWEB)

    Miyamoto, Kouji; Shimizu, Yukio; Yura, Jirou; Itoh, Yasufumi; Ikeda, Tsuneko [Matsunami General Hospital, Kasamatsu, Gifu (Japan); Outsubo, Toshio; Saitou, Hitoshi

    2001-06-01

    We report a case of radiation-induced cancer of the hypopharynx in a 65-year-old woman. The patient had received radiation treatment for Basedow's disease for several years starting at the age of 10 years. On June 26, 1993, she was examined at our hospital because of hoarseness and dysphagia. On July 22, right lobectomy was performed for suspected thyroid cancer. During this operation, endoscopy revealed hypopharyngeal cancer. Twenty-two days after surgery, total pharyngolaryngectomy and total esophagectomy were performed and a pharyngogastrostomy and a permanent tracheostomy were created. Histologic examination revealed moderately differentiated squamous cell cancer. This case was diagnosed as radiation-induced caner according to the diagnostic criteria of Sakai. (author)

  10. Treatment of Radiation Induced Biological Changes by Bone Marrow Transplantation

    International Nuclear Information System (INIS)

    Preventing the propagation of radiation induced oxidative damage has been a subject of considerable investigations. The ultimate goal of the present study is to use bone marrow cells to ameliorate or to treat the radiation sickness. Transplantation of bone marrow cell has shown promising results in the present experimental radiation treatment. In this report, suspension of bone marrow cells was injected into rats 12 h. after exposure to 4.5 Gy whole body gamma irradiation. Significant results were recorded on the successful control of the radiation induced disorders in a number of biochemical parameters including certain enzymatic and nonenzymatic antioxidants (superoxide dismutase and glutathione) and certain parameters related to kidney function including creatinine, urea as well as Atpase Activity in blood serum, urine and kidney tissue

  11. Radiation-induced defect formation in chalcogenide glasses

    Energy Technology Data Exchange (ETDEWEB)

    Shpotyuk, O.I.; Filipecki, J. [Physics Institute of Pedagogical University of Czestochowa, Al. Armii Krajowej 13/15, Czestochowa 42201 (Poland); Kozdras, A. [Physics Laboratory of Opole Technical University, 75 ul. Ozimska, Opole, PL-45370 (Poland); Kavetskyy, T.S. [Lviv Scientific Research Institute of Materials of Scientific Research Company ' Carat' , Stryjska Str. 202, Lviv, UA-79031 (Ukraine)

    2003-10-01

    The modified model of native and radiation-induced microvoid-type positron traps in vitreous chalcogenide semiconductors is developed to explain compositional features of positron annihilation lifetime measurements in stoichiometric As{sub 2}S{sub 3}-GeS{sub 2} and non-stoichiometric As{sub 2}S{sub 3}-Ge{sub 2}S{sub 3} chalcogenide glasses before and after {gamma}-irradiation.

  12. Radiation-induced apoptosis in microvascular endothelial cells.

    OpenAIRE

    Langley, R. E.; Bump, E A; Quartuccio, S. G.; Medeiros, D.; Braunhut, S. J.

    1997-01-01

    The response of the microvasculature to ionizing radiation is thought to be an important factor in the overall response of both normal tissues and tumours. It has recently been reported that basic fibroblast growth factor (bFGF), a potent mitogen for endothelial cells, protects large vessel endothelial cells from radiation-induced apoptosis in vitro. Microvessel cells are phenotypically distinct from large vessel cells. We studied the apoptotic response of confluent monolayers of capillary en...

  13. A new view of radiation-induced cancer

    OpenAIRE

    Shuryak, I.; Sachs, R K; Brenner, D J

    2010-01-01

    Biologically motivated mathematical models are important for understanding the mechanisms of radiation-induced carcinogenesis. Existing models fall into two categories: (1) short-term formalisms, which focus on the processes taking place during and shortly after irradiation (effects of dose, radiation quality, dose rate and fractionation), and (2) long-term formalisms, which track background cancer risks throughout the entire lifetime (effects of age at exposure and time since exposure) but m...

  14. Radiation-induced myeloid leukemia in murine models

    OpenAIRE

    Rivina, Leena; Davoren, Michael; Schiestl, Robert H.

    2014-01-01

    The use of radiation therapy is a cornerstone of modern cancer treatment. The number of patients that undergo radiation as a part of their therapy regimen is only increasing every year, but this does not come without cost. As this number increases, so too does the incidence of secondary, radiation-induced neoplasias, creating a need for therapeutic agents targeted specifically towards incidence reduction and treatment of these cancers. Development and efficacy testing of these agents requires...

  15. A clinical examination of radiation-induced audibility complication

    International Nuclear Information System (INIS)

    Recent clinical reports indicate that patients receiving radiotherapy that includes the auditory system in the treatment volume are likely to develop a radiation induced hearing loss. The study of effect of radiotherapy for head and neck cancer on hearing was carried out on 9 patients who had pure tone recordings before, at completion and after radiotherapy. In this study, we did not find significant hearing loss but tend to occur transient hearing loss. (author)

  16. Repair of gamma radiation-induced damage : Micrococcus radiophilus

    International Nuclear Information System (INIS)

    The gamma radiation survival curve of M. radiophilus exhibits an extensive shoulder followed by exponential kill, indicating the efficiency of this bacterium for repairing gamma radiation induced damage. It differs morphologically, biochemically and genetically from M. radiodurans. Examination of DNA strand breaks using sucrose density gradient revealed the cell's ability to repair double and single strand breaks. Studies with alkaline gradients suggest that the fast repair of single strand scissions in M. radiophilus cellular DNA may be instantaneous. (author)

  17. Quantum beam nanolithography

    International Nuclear Information System (INIS)

    Recently, nanotechnology has attracted much attention. Nanotechnology-related research and development have been intensively carried out in the world. Quantum beam nanolithography such as electron beam lithography is expected as a fabrication tool for nanotechnology-related products. For the development of materials capable of fabricating nanostructures, it is important to understand beam-material interaction. We reported radiation-induced reactions in nanolithography materials studied by ISIR subpicosecond pulse radiolysis system. (author)

  18. Xerostomia After Treatment for Oral and Oropharyngeal Cancer Using the University of Washington Saliva Domain and a Xerostomia-Related Quality-of-Life Scale

    International Nuclear Information System (INIS)

    Purpose: The first aim of this study was to identify which clinical factors are associated with xerostomia in patients after treatment for oral and oropharyngeal squamous cell carcinoma, using the Xerostomia-Related Quality-of-Life Scale (XeQoLS) and the University of Washington Quality-of-Life Questionnaire Version 4 dry mouth item (UW-QOL v4). The second aim was to compare these two questionnaires and postulate a cutoff in the UW-QOL below which patients are doing sufficient badly to warrant further evaluation and support. Methods and Materials: In all, 371 patients alive and disease free treated between 1992 and 2005 were sent the survey, of whom 250 (67%) responded. Various clinical factors correlated with xerostomia, particularly adjuvant radiotherapy and Pstage. Results: In logistic regression analyses to predict three or more problems on the XeQoLS, only adjuvant radiotherapy (p < 0.001) was significant at the 5% level. There were significant (p < 0.001) correlations between the XeQoLS scores (total average and domain) with all the UW-QOL domain scores, the strongest with swallowing (-0.69), taste (-0.64), chewing (-0.64), mood (-0.60), and saliva (-0.59) domains. Patients scoring <70 (i.e., 0 or 30) on the UW-QOL could be used as a screening cutoff because it formed 1 in 5 of all patients (49/242) but accounted for half (299/566) of the significant problems generated by the XeQoLS. This also identified 13/21 patients with 10 or more problems. Conclusion: The UW-QOL saliva domain seems to be a suitable means of screening for dry mouth in head-and-neck clinics and could be used to trigger interventions.

  19. Clarithromycin Attenuates Radiation-Induced Lung Injury in Mice.

    Directory of Open Access Journals (Sweden)

    Seung Jun Lee

    Full Text Available Radiation-induced lung injury (RILI is a common and unavoidable complication of thoracic radiotherapy. The current study was conducted to evaluate the ability of clarithromycin (CLA to prevent radiation-induced pneumonitis, oxidative stress, and lung fibrosis in an animal model. C57BL/6J mice were assigned to control, irradiation only, irradiation plus CLA, and CLA only groups. Test mice received single thoracic exposures to radiation and/or oral CLA (100 mg/kg/day. Histopathologic findings and markers of inflammation, fibrosis, and oxidative stress were compared by group. On a microscopic level, CLA inhibited macrophage influx, alveolar fibrosis, parenchymal collapse, consolidation, and epithelial cell changes. The concentration of collagen in lung tissue was lower in irradiation plus CLA mice. Radiation-induced expression of tumor necrosis factor (TNF-α, TNF receptor 1, acetylated nuclear factor kappa B, cyclooxygenase 2, vascular cell adhesion molecule 1, and matrix metallopeptidase 9 were also attenuated by CLA. Expression levels of nuclear factor erythroid 2-related factor 2 and heme oxygenase 1, transforming growth factor-β1, connective tissue growth factor, and type I collagen in radiation-treated lungs were also attenuated by CLA. These findings indicate that CLA ameliorates the deleterious effects of thoracic irradiation in mice by reducing pulmonary inflammation, oxidative damage, and fibrosis.

  20. Clarithromycin Attenuates Radiation-Induced Lung Injury in Mice.

    Science.gov (United States)

    Lee, Seung Jun; Yi, Chin-ok; Heo, Rok Won; Song, Dae Hyun; Cho, Yu Ji; Jeong, Yi Yeong; Kang, Ki Mun; Roh, Gu Seob; Lee, Jong Deog

    2015-01-01

    Radiation-induced lung injury (RILI) is a common and unavoidable complication of thoracic radiotherapy. The current study was conducted to evaluate the ability of clarithromycin (CLA) to prevent radiation-induced pneumonitis, oxidative stress, and lung fibrosis in an animal model. C57BL/6J mice were assigned to control, irradiation only, irradiation plus CLA, and CLA only groups. Test mice received single thoracic exposures to radiation and/or oral CLA (100 mg/kg/day). Histopathologic findings and markers of inflammation, fibrosis, and oxidative stress were compared by group. On a microscopic level, CLA inhibited macrophage influx, alveolar fibrosis, parenchymal collapse, consolidation, and epithelial cell changes. The concentration of collagen in lung tissue was lower in irradiation plus CLA mice. Radiation-induced expression of tumor necrosis factor (TNF)-α, TNF receptor 1, acetylated nuclear factor kappa B, cyclooxygenase 2, vascular cell adhesion molecule 1, and matrix metallopeptidase 9 were also attenuated by CLA. Expression levels of nuclear factor erythroid 2-related factor 2 and heme oxygenase 1, transforming growth factor-β1, connective tissue growth factor, and type I collagen in radiation-treated lungs were also attenuated by CLA. These findings indicate that CLA ameliorates the deleterious effects of thoracic irradiation in mice by reducing pulmonary inflammation, oxidative damage, and fibrosis. PMID:26114656

  1. Hypoxia expression in radiation-induced late rectal injury

    International Nuclear Information System (INIS)

    Tumor hypoxia and angiogenesis have been studied extensively. However, the relation between normal tissue injury and hypoxia is still unclear. In this study, we investigated the effect of hypoxia on radiation-induced late rectal injury in mice. The rectum of C57BL/6N mice was irradiated locally with a single dose of 25 Gy and the following experiments were performed including hematoxylin-eosin (H.E.) staining, azan staining, real-time polymerase chain reaction (PCR), immunohistochemistry and immunofluorescence. Radiation-induced fibrotic changes were observed from 14 days and reached the peak 30 days after irradiation. The expression of transforming growth factor β1 (TGF-β1), hypoxia-inducible factor-1α (HIF-1α), vascular endothelial growth factor (VEGF) and endothelial cell marker CD31 increased significantly with the formation of fibrosis induced by irradiation compared with unirradiated control. In addition, the maximum expression of TGF-β1, HIF-1α and VEGF was found at 14, 30 and 90 days after irradiation, respectively. The temporal changes of cytokines were consistent with the dynamic change of fibrosis. Our data suggests that late normal tissue injury involved various cytokines including hypoxia-induced angiogenic cytokines. These results may have important implications in the understanding of radiation-induced late normal tissue injury. (author)

  2. Rabbit model of radiation-induced lung injury

    Institute of Scientific and Technical Information of China (English)

    Zhen-Zong Du; Hua Ren; Jian-Fei Song; Li-Fei Zhang; Feng Lin; Hai-Yong Wang

    2013-01-01

    Objective:To explore the feasibility of establishing an animal model of chronic radiation-induced lung injury.Methods:Twenty-eightNewZealand white rabbits were randomly divided into3 groups(the right lung irradiation group, the whole lung irradiation group and the control group).Animal model of radiation-induced lung injury was established by high-does radiotherapy in the irradiation groups, then all rabbits underwentCT and pathological examinations at1,2,4,8,12,16 weeks, respectively after radiation.Results:Within4 weeks of irradiation, some rabbits in the right lung irradiation group and whole lung irradiation group died. CT and pathological examinations all showed acute radiation pneumonitis.At8-12 weeks after irradiation,CT scanning showed ground glass samples signs, patchy shadows and fibrotic stripes. Pathological examination showed the fibrosis pulmonary alveolar wall thickened obviously. Conclusions:The clinical animal model of chronic radiation-induced lung injury which corresponds to practical conditions in clinic can be successfully established.

  3. Radiation induced structural changes in alpha-copper-zinc alloys

    International Nuclear Information System (INIS)

    During irradiation of alpha-copper-zinc alloys with high energy electrons and protons a decrease of the electrical resistivity due to an increase of the degree of short range order is observed through radiation enhanced diffusion followed by an increase of the electrical resistivity through the formation of radiation induced interstitial clusters. The initial formation rate of interstitial clusters increases about linearly with the displacement rate for electron and proton irradiation. The largest initial formation rate is found between 60 and 1300C becoming negligibly small above 1580C and decreases drastically below 600C. The dynamic steady state interstitial cluster concentration increases with decreasing irradiation temperature in the investigated temperature range between 158 and 400C. Above 1580C the formation rate of interstitial clusters is negligibly small. Thus the transition temperature for radiation induced interstitial cluster formation is 1580C, depending mainly on the migration activation energy of vacancies. The radiation induced interstitial clusters are precipitates in those alloys in which the diffusion rate of the undersized component atoms via an interstitialcy diffusion mechanism is larger than that of the other atoms

  4. Establishment of murine model of radiation-induced oral mucositis

    International Nuclear Information System (INIS)

    Objective: To establish a murine model of radiation-induced oral mucositis. Methods: Left-sided buccal mucosa of 70 Sprague-Dawley rats were irradiated with X-rays (10 Gy/d), then six rats, selected randomly, were sacrificed at the 2nd, 4th, 6th, 8th, 14th, and 21st day after the irradiation, left-sided buccal mucosa were excised, corresponding irradiation dose for the selected rats were 20, 40, 60 and 80 Gy following radiation. The right buccal mucosa was excised and treated as its auto-controls tissue. Results: Erythema was observed in the left-sided buecal mucosa in rates irradiated with X-rays of 60 Gy; a single or more ulcers observed in rates irradiated with 80 Gy X-rays; a large area of ulcer was observed at 4th day after 80 Gy irradiation. The radiation-induced ulcer in buccal mucosa was essentially recovered after about 2 weeks following 80 Gy irradiation. Conclusion: This murine model of radiation-induced oral mucositis was useful and practical in experimental studies. (authors)

  5. Radiation induced enterocolitis in uterine cervical cancer after radiotherapy

    International Nuclear Information System (INIS)

    Objective: To approach the cause of radiation induced enterocolitis and its relationship with retropostion of the uterus in uterine cervical cancer after radiotherapy. Methods: Twenty-two patients with radiation induced enterocolitis, from 212 patients with uterine cervical cancer who had received radio-therapy during 2002-2005, were retrospectively analyzed. The incidence between patients with anteposition and patients with retroposition of uterus was compared. The distance between uterine central axis and the rectum of 15 patients with anteposition and 15 patients with retroposition of the uterus was measured, as well as the uterus retroversional flexion angle of the retropositioned uterus. Results: The incidence of radiation enterocolitis in patients with retroposition of uterus was obviously higher than that in patients with anteposition (χ2=21.10, P<0.01). The distance between point C and the rectum in patients with retroposition of uterus was shorter(t=7.33, P<0.05). The retroversional flexion angle of retropostitioned uterus were between 9-22 degree with a median angle of 17 degree. Conclusion: The incidence of radiation induced enterocolitis is higher in patients with retropostition of uterus after radiotherapy, because the distance between the uterine central axis and the rectum is shorter. The y axis and z axis often form an acute angle in the rectal direction during after-loading therapy, which would had led to an excessive dose to the rectum. (authors)

  6. Radiation-Induced Differentiation in Human Lung Fibroblast

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sa-Rah; Ahn, Ji-Yeon; Han, Young-Soo; Shim, Jie-Young; Yun, Yeon-Sook; Song, Jie-Young [Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of)

    2007-10-15

    One of the most common tumors in many countries is lung cancer and patients with lung cancer may take radiotherapy. Although radiotherapy may have its own advantages, it can also induce serious problems such as acute radiation pneumonitis and pulmonary fibrosis. Pulmonary fibrosis is characterized by excessive production of {alpha}-SMA and accumulation of extracellular matrix (ECM) such as collagen and fibronectin. There has been a great amount of research about fibrosis but the exact mechanism causing the reaction is not elucidated especially in radiation-induced fibrosis. Until now it has been known that several factors such as transforming growth factor (TGF-{beta}), tumor necrosis factor (TNF), interleukin (IL)-1, IL-6, platelet-derived growth factor (PDGF) and fibroblast growth factor (FGF) are related to fibrosis. Among them TGF-{beta} with Smad signaling is known to be the main stream and other signaling molecules such as MAPK, ERK and JNK (3) also participates in the process. In addition to those above factors, it is thought that more diverse and complicate mechanisms may involve in the radiationinduced fibrosis. Therefore, to investigate the underlying mechanisms in radiation induced fibrosis, first of all, we confirmed whether radiation induces trans differentiation in human normal lung fibroblasts. Here, we suggest that not only TGF-{beta} but also radiation can induce trans differentiation in human lung fibroblast WI-38 and IMR-90.

  7. Radiation-induced products of peptides and their enzymatic digestibility

    International Nuclear Information System (INIS)

    Chemical characterization of radiation-induced products of peptides and proteins is essential for understanding the effect of ionizing radiation on peptides and proteins. Furthermore, peptides containing radiation-altered amino acid residues might not be completely digestible by proteolytic enzymes. In this work, small homopeptides of Ala, Phe and Met were chosen as model peptides. Lysozyme was used to investigate the effect of ionizing radiation on a small protein. All peptides and lysozyme were irradiated in diluted, oxygen free, N2O-saturated aqueous solutions, using a 60Co-γ-source. HPLC, capillary GC and GC-MS were applied to isolate and characterize the radiation-induced products. The enzymatic digestibility of the products was investigated using aminopeptidase M, leucine aminopeptidase, carboxypeptidase A and carboxypeptidase Y. It was found that irradiation of peptides examined in this work leads to racemization and alteration of amino acid residues and crosslinks between the peptide chains. In addition, it was established that exopeptidases act differently on radiation-induced dimers of peptides composed of aliphatic, aromatic and sulfur-containing amino acids

  8. Radiation-induced pseudotumor following therapy for soft tissue sarcoma

    Energy Technology Data Exchange (ETDEWEB)

    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

  9. Radiation-induced pseudotumor following therapy for soft tissue sarcoma

    International Nuclear Information System (INIS)

    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

  10. The role of Fas in radiation induced apoptosis in vivo

    International Nuclear Information System (INIS)

    It has been recognized that interaction of the Fas: Fas ligand plays an important role in radiation-induced apoptosis. The purpose of this study was to investigate the role of Fas mutation in radiation-induced apoptosis in vivo. Mice with mutations in Fas, MRL/Mpj Faslpr, and its normal control, MRL/Mpj, were used in this study. Eight-week old male mice were given whole body radiation. After irradiation, the mice were killed and their spleens were collected at different time intervals. Tissue samples were stained with hematoxylin-eosin and the numbers of apoptotic cells were scored. Regulating molecules of apoptosis including p53, Bcl-2, Bax, Bcl-XL, and Bcl-Xs were also analyzed by Western blotting. At 25 Gy irradiation, the level of apoptosis reached the peak value at 8 hr after radiation and recovered to the normal value at 24 hr after radiation in MRL/Mpj mice. In contrast, the peak apoptosis level appeared at 4 hr after radiation in MRL/Mpj-Faslpr mice. At 8 hr after radiation, the levels of apoptosis in MRL/Mpj mice and MRL/Mpj-Faslpr mice were 52.3 ± 7.8% and 8.0 ± 8.6%, respectively (ρ L, and Bcl-Xs, increased in MRL/Mpj mice in response to radiation; p53 with a peak level of 3-fold at 8 h, Bcl-XL with a peak level of 3.3-fold at 12 h, and Bcl-Xs with a peak level of 3-fold at 12 h after 25 Gy radiation. Bcl-2 and Bax did not show significant change in MRL/Mpj mice. However in MRL/Mpj-Faslpr mice, the expression levels of p53, Bcl-2, Bax, Bcl-XL, and Bcl-Xs showed no significant change. The level of radiation-induced apoptosis was lower in Fas mutated mice, lpr, than in control mice. This seemed to be related to the lack of radiation-induced p53 activation in the lpr mice. This result suggests that Fas plays an important role in radiation-induced apoptosis in vivo

  11. The role of Fas in radiation induced apoptosis in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sung Hee; Seong, Jin Sil; Seong, Je Kyung [Yonsei University Medical College, Seoul (Korea, Republic of)

    2002-09-15

    It has been recognized that interaction of the Fas: Fas ligand plays an important role in radiation-induced apoptosis. The purpose of this study was to investigate the role of Fas mutation in radiation-induced apoptosis in vivo. Mice with mutations in Fas, MRL/Mpj Fas{sup lpr}, and its normal control, MRL/Mpj, were used in this study. Eight-week old male mice were given whole body radiation. After irradiation, the mice were killed and their spleens were collected at different time intervals. Tissue samples were stained with hematoxylin-eosin and the numbers of apoptotic cells were scored. Regulating molecules of apoptosis including p53, Bcl-2, Bax, Bcl-X{sub L}, and Bcl-X{sub s} were also analyzed by Western blotting. At 25 Gy irradiation, the level of apoptosis reached the peak value at 8 hr after radiation and recovered to the normal value at 24 hr after radiation in MRL/Mpj mice. In contrast, the peak apoptosis level appeared at 4 hr after radiation in MRL/Mpj-Fas{sup lpr} mice. At 8 hr after radiation, the levels of apoptosis in MRL/Mpj mice and MRL/Mpj-Fas{sup lpr} mice were 52.3 {+-} 7.8% and 8.0 {+-} 8.6%, respectively ({rho} < 0.05). The expression of apoptosis regulating molecules, p53, Bcl-X{sub L}, and Bcl-X{sub s}, increased in MRL/Mpj mice in response to radiation; p53 with a peak level of 3-fold at 8 h, Bcl-X{sub L} with a peak level of 3.3-fold at 12 h, and Bcl-X{sub s} with a peak level of 3-fold at 12 h after 25 Gy radiation. Bcl-2 and Bax did not show significant change in MRL/Mpj mice. However in MRL/Mpj-Fas{sup lpr} mice, the expression levels of p53, Bcl-2, Bax, Bcl-X{sub L}, and Bcl-X{sub s} showed no significant change. The level of radiation-induced apoptosis was lower in Fas mutated mice, lpr, than in control mice. This seemed to be related to the lack of radiation-induced p53 activation in the lpr mice. This result suggests that Fas plays an important role in radiation-induced apoptosis in vivo.

  12. Radiation-induced degradation of water pollutants - state of the art

    Energy Technology Data Exchange (ETDEWEB)

    Getoff, N. [Vienna Univ. (Austria). Inst. fuer Theoretische Chemie und Strahlenchemie]|[Ludwig-Boltzmann-Institut fuer Veterinaermedizinische Endokrinologie, Vienna (Austria)

    1996-04-01

    The radiation-induced decomposition of biological resistant pollutants in drinking as well as in wastewater is briefly reviewed. First, some important units, definitions etc., radiation sources, as well as dose-depth curves in water as functions of the electron energy and {sup 60}Co-{gamma}-rays are mentioned. Following is a schematical presentation of water radiolysis and of characteristics of primary free radicals. Then the degradation of some aliphatic and aromatic chlorinated compounds in the presence of air is presented. Some spectroscopic and kinetic data of transients resulting from chlorinated phenols are also quoted in order to illustrate and to explain the rather complicated degradation mechanisms. In this respect the synergistic effect of radiation and oxygen as well as that of ozone is also discussed. Finally, a scheme for technical application of high energy electron beam is presented. (author).

  13. Two-stage autotransplantation of human submandibular gland: a novel approach to treat postradiogenic xerostomia.

    Science.gov (United States)

    Hagen, Rudolf; Scheich, Matthias; Kleinsasser, Norbert; Burghartz, Marc

    2016-08-01

    Xerostomia is a persistent side effect of radiotherapy (RT), which severely reduces the quality of life of the patients affected. Besides drug treatment and new irradiation strategies, surgical procedures aim for tissue protection of the submandibular gland. Using a new surgical approach, the submandibular gland was autotransplanted in 6 patients to the patient's forearm for the period of RT and reimplanted into the floor of the mouth 2-3 months after completion of RT. Saxon's test was performed during different time points to evaluate patient's saliva production. Furthermore patients had to answer EORTC QLQ-HN35 questionnaire and visual analog scale. Following this two-stage autotransplantation, xerostomia in the patients was markedly reduced due to improved saliva production of the reimplanted gland. Whether this promising novel approach is a reliable treatment option for RT patients in general should be evaluated in further studies. PMID:26285780

  14. Parotid gland sparing IMRT for head and neck cancer improves xerostomia related quality of life

    Directory of Open Access Journals (Sweden)

    Balm AJM

    2008-12-01

    Full Text Available Abstract Background and purpose To assess the impact of intensity modulated radiotherapy (IMRT versus conventional radiation on late xerostomia and Quality of Life aspects in head and neck cancer patients. Patients and nethods Questionnaires on xerostomia in rest and during meals were sent to all patients treated between January 1999 and December 2003 with a T1-4, N0-2 M0 head and neck cancer, with parotid gland sparing IMRT or conventional bilateral neck irradiation to a dose of at least 60 Gy, who were progression free and had no disseminated disease (n = 192. Overall response was 85% (n = 163; 97% in the IMRT group (n = 75 and 77% in the control group (n = 88 the median follow-up was 2.6 years. The prevalence of complaints was compared between the two groups, correcting for all relevant factors at multivariate ordinal regression analysis. Results Patients treated with IMRT reported significantly less difficulty transporting and swallowing their food and needed less water for a dry mouth during day, night and meals. They also experienced fewer problems with speech and eating in public. Laryngeal cancer patients in general had fewer complaints than oropharynx cancer patients but both groups benefited from IMRT. Within the IMRT group the xerostomia scores were better for those patients with a mean parotid dose to the "spared" parotid below 26 Gy. Conclusion Parotid gland sparing IMRT for head and neck cancer patients improves xerostomia related quality of life compared to conventional radiation both in rest and during meals. Laryngeal cancer patients had fewer complaints but benefited equally compared to oropharyngeal cancer patients from IMRT.

  15. Hyperglycemia and xerostomia are key determinants of tooth decay in type 1 diabetic mice

    OpenAIRE

    Yeh, Chih-Ko; Harris, Stephen E.; Mohan, Sumathy; Horn, Diane; Fajardo, Roberto; Chun, Yong-Hee Patricia; Jorgensen, James; Macdougall, Mary; Abboud-Werner, Sherry

    2012-01-01

    Insulin-dependent type 1 diabetes mellitus (DM) and oral diseases are closely interrelated. Poor metabolic control in diabetics is associated with a high risk of gingivitis, periodontitis and tooth loss. Salivary flow declines in diabetics and patients suffer from xerostomia. Reduced saliva predisposes to enamel hypomineralization and caries formation; however, the mechanisms that initiate and lead to progression of tooth decay and periodontitis in type 1 DM have not been explored. To address...

  16. Parotid gland sparing IMRT for head and neck cancer improves xerostomia related quality of life

    International Nuclear Information System (INIS)

    To assess the impact of intensity modulated radiotherapy (IMRT) versus conventional radiation on late xerostomia and Quality of Life aspects in head and neck cancer patients. Questionnaires on xerostomia in rest and during meals were sent to all patients treated between January 1999 and December 2003 with a T1-4, N0-2 M0 head and neck cancer, with parotid gland sparing IMRT or conventional bilateral neck irradiation to a dose of at least 60 Gy, who were progression free and had no disseminated disease (n = 192). Overall response was 85% (n = 163); 97% in the IMRT group (n = 75) and 77% in the control group (n = 88) the median follow-up was 2.6 years. The prevalence of complaints was compared between the two groups, correcting for all relevant factors at multivariate ordinal regression analysis. Patients treated with IMRT reported significantly less difficulty transporting and swallowing their food and needed less water for a dry mouth during day, night and meals. They also experienced fewer problems with speech and eating in public. Laryngeal cancer patients in general had fewer complaints than oropharynx cancer patients but both groups benefited from IMRT. Within the IMRT group the xerostomia scores were better for those patients with a mean parotid dose to the 'spared' parotid below 26 Gy. Parotid gland sparing IMRT for head and neck cancer patients improves xerostomia related quality of life compared to conventional radiation both in rest and during meals. Laryngeal cancer patients had fewer complaints but benefited equally compared to oropharyngeal cancer patients from IMRT

  17. Xerostomia after radiotherapy. What matters - mean total dose or dose to each parotid gland?

    International Nuclear Information System (INIS)

    Purpose: Xerostomia is a debilitating side effect of radiotherapy in patients with head and neck cancer. We undertook a prospective study of the effect on xerostomia and outcomes of sparing one or both parotid glands during radiotherapy for patients with squamous cell carcinoma of the head and neck. Methods and materials: Patients with locally advanced squamous cell carcinoma of the head and neck received definitive (70 Gy in 2 Gy fractions) or adjuvant (60-66 Gy in 2 Gy fractions) curative-intent radiotherapy using helical tomotherapy with concurrent chemotherapy if appropriate. Group A received < 26 Gy to the left and right parotids and group B received < 26 Gy to either parotid. Results: The study included 126 patients; 114 (55 in group A and 59 in group B) had follow-up data. There were no statistically significant differences between groups in disease stage. Xerostomia was significantly reduced in group A vs. group B (p = 0.0381). Patients in group A also had significantly less dysphagia. Relapse-free and overall survival were not compromised in group A: 2-year relapse-free survival was 86% vs. 72% in group B (p = 0.361); 2-year overall survival was 88% and 76%, respectively (p = 0.251). Conclusion: This analysis suggests that reducing radiotherapy doses to both parotid glands to < 26 Gy can reduce xerostomia and dysphagia significantly without compromising survival. Sparing both parotids while maintaining target volume coverage and clinical outcome should be the treatment goal and reporting radiotherapy doses delivered to the individual parotids should be standard practice. (orig.)

  18. Parotid gland shrinkage during IMRT predicts the time to Xerostomia resolution

    OpenAIRE

    Sanguineti, Giuseppe; RICCHETTI, FRANCESCO; Wu, Binbin; McNutt, Todd; Fiorino, Claudio

    2015-01-01

    Purpose To assess the impact of mid-treatment parotid gland shrinkage on long term xerostomia during IMRT for oropharyngeal SCC. Methods and materials All patients treated with IMRT at a single Institution from November 2007 to June 2010 and undergoing weekly CT scans were selected. Parotid glands were contoured retrospectively on the mid treatment CT scan. For each parotid gland, the percent change relative to the planning volume was calculated and combined as weighted average. Patients were...

  19. Xerostomia after radiotherapy. What matters - mean total dose or dose to each parotid gland?

    Energy Technology Data Exchange (ETDEWEB)

    Tribius, S.; Sommer, J.; Prosch, C.; Bajrovic, A.; Kruell, A.; Petersen, C. [University Medical Center Hamburg-Eppendorf, Hamburg (Germany). Dept. of Radiation Oncology; Muenscher, A. [University Medical Center Hamburg-Eppendorf, Hamburg (Germany). Dept. of Otorhinolaryngology and Head and Neck Surgery; Blessmann, M. [University Medical Center Hamburg-Eppendorf, Hamburg (Germany). Dept. of Oral and Maxillofacial Surgery; Todorovic, M. [University Medical Center Hamburg-Eppendorf, Hamburg (Germany). Dept. of Medical Physics; Tennstedt, P. [University Medical Center Hamburg-Eppendorf, Hamburg (Germany). Martini-Clinic, Prostate Cancer Center

    2013-03-15

    Purpose: Xerostomia is a debilitating side effect of radiotherapy in patients with head and neck cancer. We undertook a prospective study of the effect on xerostomia and outcomes of sparing one or both parotid glands during radiotherapy for patients with squamous cell carcinoma of the head and neck. Methods and materials: Patients with locally advanced squamous cell carcinoma of the head and neck received definitive (70 Gy in 2 Gy fractions) or adjuvant (60-66 Gy in 2 Gy fractions) curative-intent radiotherapy using helical tomotherapy with concurrent chemotherapy if appropriate. Group A received < 26 Gy to the left and right parotids and group B received < 26 Gy to either parotid. Results: The study included 126 patients; 114 (55 in group A and 59 in group B) had follow-up data. There were no statistically significant differences between groups in disease stage. Xerostomia was significantly reduced in group A vs. group B (p = 0.0381). Patients in group A also had significantly less dysphagia. Relapse-free and overall survival were not compromised in group A: 2-year relapse-free survival was 86% vs. 72% in group B (p = 0.361); 2-year overall survival was 88% and 76%, respectively (p = 0.251). Conclusion: This analysis suggests that reducing radiotherapy doses to both parotid glands to < 26 Gy can reduce xerostomia and dysphagia significantly without compromising survival. Sparing both parotids while maintaining target volume coverage and clinical outcome should be the treatment goal and reporting radiotherapy doses delivered to the individual parotids should be standard practice. (orig.)

  20. Dry Eye Disease Patients with Xerostomia Report Higher Symptom Load and Have Poorer Meibum Expressibility

    OpenAIRE

    Fostad, Ida G.; Eidet, Jon R.; Tor P. Utheim; Ræder, Sten; Lagali, Neil S.; Messelt, Edvard B.; Dartt, Darlene A.

    2016-01-01

    The purpose of the study was to investigate if xerostomia (dry mouth) is associated with symptoms and signs of dry eye disease (DED). At the Norwegian Dry Eye Clinic, patients with symptomatic DED with different etiologies were consecutively included in the study. The patients underwent a comprehensive ophthalmological work-up and completed self-questionnaires on symptoms of ocular dryness (Ocular Surface Disease Index [OSDI] and McMonnies Dry Eye Questionnaire) and the Sjögren’s syndrome (SS...

  1. Dose–response analysis of parotid gland function: What is the best measure of xerostomia?

    International Nuclear Information System (INIS)

    Purpose: To describe the dose–response relationships for the different measures of salivary gland recovery following radical radiotherapy for locally advanced head and neck squamous cell cancers (LA-HNSCC). Methods and materials: Dosimetric analysis of data from the PARSPORT trial, a Phase III study of conventional RT (RT) and intensity modulated radiotherapy (IMRT) for LA-HNSCC was undertaken to determine the relationship between parotid gland mean dose and toxicity endpoints: high-grade subjective and objective xerostomia and xerostomia-related quality of life scores. LKB-NTCP parameters (TD50, m and n) were generated and tolerance doses (D50) reported using non-linear logistic regression analysis. Results: Data were available on 63 patients from the PARSPORT trial. Parotid saliva flow rate provided the strongest association between mean dose and recovery, D50 = 23.4 Gy (20.6–26.2) and k = 3.2 (1.9–4.5), R2 = 0.85. Corresponding LKB parameters were TD50 = 26.3 Gy (95% CI: 24.0–30.1), m = 0.25 (0.18–1.0 and n = 1). LENTSOMA subjective xerostomia also demonstrated a strong association D50 = 33.3 Gy (26.7–39.8), k = 2.8 (91.4–4.4), R2 = 0.77). Conclusion: We recommend using the LENT SOMA subjective xerostomia score to predict recovery of salivation due to its strong association with dosimetry and ease of recording

  2. Evaluation of xerostomia and taste disturbance after radiotherapy of patients with head and neck lesion

    International Nuclear Information System (INIS)

    Because of high sensitivity to radiation, radiotherapy to the head and neck cancer is often conducted for purposes of functional preservation. However, the salivary glands and oral cavity must be included in the irradiation field. Thus, an inflammatory reaction of the oral mucosa to the radiotherapy is inevitable, and xerostomia, taste disturbance, and pain appear in the early stage of the treatment. These side effects sometimes cause not only interrupt or change planned treatment but also influence patients' Quality of Life after treatment. Thus, we conducted, in the form of questionnaire surveys, subjective and objective evaluations in respect to xerostomia and taste disturbance, and assessed the usefulness of the evaluations. The subjects were 40 patients who had received the radiotherapy in the major salivary glands, such as parotid glands, and almost the whole tongue, but who had not undergo a resection of the major salivary glands or tongue. The degree of damage to the salivary glands and taste were evaluated, subjectively and objectively. The subjective evaluation was conducted by questionnaires given to the patients. As for the objective evaluation, xerostomia was evaluated by measuring the salivary amount, while the taste disturbance was examined in 27 patients using taste disks. The results showed a positive correlation, indicating that the evaluation of xerostomia and taste disturbance using questionnaires is useful. The salivary amount was the least at six months after the radiotherapy, then increased gradually, and 24 months later, improved to a level similar to that seen immediately after the radiotherapy. The taste disturbance also improved gradually over the 24 months following radiotherapy. (author)

  3. The impact of xerostomia on oral-health-related quality of life among younger adults

    Directory of Open Access Journals (Sweden)

    Broadbent Jonathan M

    2006-11-01

    Full Text Available Abstract Background Recent research has suggested that chronic dry mouth affects the day-to-day lives of older people living in institutions. The condition has usually been considered to be a feature of old age, but recent work by our team produced the somewhat surprising finding that 10% of people in their early thirties are affected. This raises the issue of whether dry mouth is a trivial condition or a more substantial threat to quality of life among younger people. The objective of this study was to examine the association between xerostomia and oral-health-related quality of life among young adults while controlling for clinical oral health status and other potential confounding factors. Methods Cross-sectional analysis of data from a longstanding prospective observational study of a Dunedin (New Zealand birth cohort: clinical dental examinations and questionnaires were used at age 32. The main measures were xerostomia (the subjective feeling of dry mouth, measured with a single question and oral-health-related quality of life (OHRQoL measured using the short-form Oral Health Impact Profile (OHIP-14. Results Of the 923 participants (48.9% female, one in ten were categorised as 'xerostomic', with no apparent gender difference. There was a strong association between xerostomia and OHRQoL (across all OHIP-14 domains which persisted after multivariate analysis to control for clinical characteristics, gender, smoking status and personality characteristics (negative emotionality and positive emotionality. Conclusion Xerostomia is not a trivial condition; it appears to have marked and consistent effects on sufferers' day-to-day lives.

  4. Radiation-induced segregation in austenitic stainless steel type 304: Effect of high fraction of twin boundaries

    International Nuclear Information System (INIS)

    Highlights: · High fraction of twin boundaries obtained using thermo-mechanical processing. · Electrochemical evaluation of radiation-induced segregation. · Effect of high fraction of twins on radiation-induced segregation. · Twin boundaries act as sinks, reduced point defect adsorption at grain boundaries. - Abstract: The effect of high fraction of twin boundaries on radiation-induced segregation (RIS) in type 304 stainless steel (SS) was investigated using 4.8 MeV proton beam at 300 deg. C. Type 304 SS samples were irradiated to 0.86 and 1.00 displacement per atom (dpa) and characterization of RIS was done using Electrochemical Potentiokinetic Reactivation (EPR) tests at different depth from the surface. Localized attack on different microstructural features, grain and twin boundaries and in-grain pit-like features, was further evaluated by atomic force microscopy. The results clearly indicated that attack was mostly confined to twin boundaries, implying that the twin boundaries acted as a preferred defect sink.

  5. Radiation-Induced Cranial Nerve Palsy: A Cross-Sectional Study of Nasopharyngeal Cancer Patients After Definitive Radiotherapy

    International Nuclear Information System (INIS)

    Purpose: To address the characteristics and the causative factors of radiation-induced cranial nerve palsy (CNP) in nasopharyngeal carcinoma (NPC) patients with an extensive period of followed-up. Patients and Methods: A total of 317 consecutive and nonselected patients treated with definitive external-beam radiotherapy between November 1962 and February 1995 participated in this study. The median doses to the nasopharynx and upper neck were 71 Gy (range, 55-86 Gy) and 61 Gy (range, 34-72 Gy), respectively. Conventional fractionation was used in 287 patients (90.5%). Forty-five patients (14.2%) received chemotherapy. Results: The median follow-up was 11.4 years (range, 5.1-38.0 years). Ninety-eight patients (30.9%) developed CNP, with a median latent period of 7.6 years (range, 0.3-34 years). Patients had a higher rate of CNP (81 cases, 25.5%) in lower-group cranial nerves compared with upper group (44 cases, 13.9%) (χ2 = 34.444, p 2 = 4.661, p = 0.031). The cumulative incidences of CNP were 10.4%, 22.4%, 35.5%, and 44.5% at 5, 10, 15, and 20 years, respectively. Multivariate analyses revealed that CNP at diagnosis, chemotherapy, total radiation dose to the nasopharynx, and upper neck fibrosis were independent risk factors for developing radiation-induced CNP. Conclusion: Radiation-induced fibrosis may play an important role in radiation-induced CNP. The incidence of CNP after definitive radiotherapy for NPC remains high after long-term follow-up and is dose and fractionation dependent.

  6. Analysis of Factors Associated With Radiation-Induced Bronchiolitis Obliterans Organizing Pneumonia Syndrome After Breast-Conserving Therapy

    International Nuclear Information System (INIS)

    Purpose: To evaluate factors associated with radiation-induced bronchiolitis obliterans organizing pneumonia (BOOP) syndrome after breast-conserving therapy. Methods and Materials: A total of 702 women with breast cancer who received radiotherapy after breast-conserving surgery at seven institutions between July 1995 and December 2006 were analyzed. In all patients, the whole breast was irradiated with two tangential photon beams. The criteria used for the diagnosis of radiation-induced BOOP syndrome were as follows: (1) radiotherapy to the breast within 12 months, (2) general and/or respiratory symptoms lasting for ≥2 weeks, (3) radiographs showing lung infiltration outside the radiation port, and (4) no evidence of a specific cause. Results: Radiation-induced BOOP syndrome was seen in 16 patients (2.3%). Eleven patients (68.8%) were administered steroids. The duration of steroid administration ranged from 1 week to 3.7 years (median, 1.1 years). Multivariate analysis revealed that age (≥50 years; odds ratio [OR] 8.88; 95% confidence interval [CI] 1.16-67.76; p = 0.04) and concurrent endocrine therapy (OR 3.05; 95% CI 1.09-8.54; p = 0.03) were significantly associated with BOOP syndrome. Of the 161 patients whose age was ≥50 years and who received concurrent endocrine therapy, 10 (6.2%) developed BOOP syndrome. Conclusions: Age (≥50 years) and concurrent endocrine therapy can promote the development of radiation-induced BOOP syndrome after breast-conserving therapy. Physicians should carefully follow patients who received breast-conserving therapy, especially those who are older than 50 years and received concurrent endocrine therapy during radiotherapy

  7. Impact of head and neck cancer adaptive radiotherapy to spare the parotid glands and decrease the risk of xerostomia

    International Nuclear Information System (INIS)

    Large anatomical variations occur during the course of intensity-modulated radiation therapy (IMRT) for locally advanced head and neck cancer (LAHNC). The risks are therefore a parotid glands (PG) overdose and a xerostomia increase. The purposes of the study were to estimate: - the PG overdose and the xerostomia risk increase during a “standard” IMRT (IMRTstd); - the benefits of an adaptive IMRT (ART) with weekly replanning to spare the PGs and limit the risk of xerostomia. Fifteen patients received radical IMRT (70 Gy) for LAHNC. Weekly CTs were used to estimate the dose distributions delivered during the treatment, corresponding either to the initial planning (IMRTstd) or to weekly replanning (ART). PGs dose were recalculated at the fraction, from the weekly CTs. PG cumulated doses were then estimated using deformable image registration. The following PG doses were compared: pre-treatment planned dose, per-treatment IMRTstd and ART. The corresponding estimated risks of xerostomia were also compared. Correlations between anatomical markers and dose differences were searched. Compared to the initial planning, a PG overdose was observed during IMRTstd for 59% of the PGs, with an average increase of 3.7 Gy (10.0 Gy maximum) for the mean dose, and of 8.2% (23.9% maximum) for the risk of xerostomia. Compared to the initial planning, weekly replanning reduced the PG mean dose for all the patients (p < 0.05). In the overirradiated PG group, weekly replanning reduced the mean dose by 5.1 Gy (12.2 Gy maximum) and the absolute risk of xerostomia by 11% (p < 0.01) (30% maximum). The PG overdose and the dosimetric benefit of replanning increased with the tumor shrinkage and the neck thickness reduction (p < 0.001). During the course of LAHNC IMRT, around 60% of the PGs are overdosed of 4 Gy. Weekly replanning decreased the PG mean dose by 5 Gy, and therefore by 11% the xerostomia risk

  8. Radioprotective effects of melatonin on radiation-induced cataract

    International Nuclear Information System (INIS)

    One of the mechanisms proposed to explain lens opacification is the oxidation of crystallins, either by radiation or reactive oxygen species (ROS). It has been shown that melatonin has both an anti-peroxidative effect on several tissues and a scavenger effect on ROS. The purpose of this study was to determine the antioxidant role of melatonin (5 mg/kg/day) against radiation-induced cataract in the lens after total-cranium irradiation of rats with a single dose of 5 Gy. Sprague-Dawley rats were divided into four groups. Control group received neither melatonin nor irradiation. Irradiated rats (IR) and melatonin+irradiated rats (IR+Mel) groups were exposed to total cranium irradiation of 5 Gy in a single dose by using a cobalt-60 teletherapy unit. IR+Mel and melatonin (Mel) groups were administered 5 mg/kg melatonin daily by intraperitoneal injections during ten days. Chylack's cataract classification was used in this study. At the end of the 10th day, the rats were killed and their eyes were enucleated to measure the antioxidant enzymes i.e. the activity of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), and lipid peroxidation level (malondialdehyde (MDA)). Irradiation significantly increased the MDA level, as an end product of lipid peroxidation, and also significantly decreased SOD and GSH-Px activity, emphasizing the generation of increased oxidative stress. Rats injected with melatonin only did not cause cataract formation. Melatonin supplementation with irradiation significantly increased the activity of SOD and GSH-Px enzymes and significantly decreased the MDA level. Total cranium irradiation of 5 Gy in a single dose enhanced cataract formation, and melatonin supplementation protected the lenses from radiation-induced cataract formation. Our results suggest that supplementing cancer patients with adjuvant therapy of melatonin may reduce patients suffering from toxic therapeutic regimens such as chemotherapy and/or radiotherapy and may provide

  9. p53-dependent apoptosis suppresses radiation-induced teratogenesis

    International Nuclear Information System (INIS)

    About half of human conceptions are estimated not to be implanted in the uterus, resulting in unrecognizable spontaneous abortions. Experimental studies with mice have established that irradiation during the preimplantation period of the embryo induces a high incidence of prenatal deaths but virtually no malformations. This suggests that some mechanism is screening out the damaged fetuses. In order to elucidate the mechanisms of tissue repair of radiation-induced teratogenic injury, we compared the incidences of radiation-induced malformations and abortions in p53 null (p53-/-) and wild-type (p53+/+) mice. After X-irradiation with 2 Gy on day 9.5 of gestation, p53-/- mice showed a 70% incidence of anomalies and a 7% incidence of deaths, whereas p53+/+ mice had a 20% incidence of anomalies and a 60% incidence of deaths. Similar results were obtained after irradiation on day 3.5 of gestation. This reciprocal relationship of radiosensitivity to anomalies and to embryonic or fetal lethality supports the notion that the p53 gene protects embryos and fetuses against the teratogenic effects of radiation by eliminating cells that have been badly damaged. In fact, after X-irradiation, the frequency of dying cells by apoptosis was greatly increased in tissues of the p53+/+ fetuses but not at all in those of the p53-/- fetuses. Mammals are protected from radiation-induced injury by two mechanisms, p53-dependent apoptotic tissue repair in addition to well known DNA repair. Therefore, there are threshold doses below which there is no induction of teratogenic and carcinogenic effects after exposure to low-level radiation. (author)

  10. Construction of radiation - induced metastasis model in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jong Kuk; Jang, Su Jin; Kang, Sung Wook; Kim, Jae Sung; Hwang, Sang Gu; Kang, Joo Hyun [Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of)

    2011-05-15

    In treatment of cancer, distant metastases are important limiting factor because an estimated 50% of all cancer patients will develop metastases, and the metastases are major causing of cancer treatment failure. Recently a few reports indicated {gamma}-radiation induced an increase of invasiveness of several cancer cells. In this study, we had tried to show the possibility that radiation could also induce metastasis in vivo system. To prove our hypothesis, we constructed primary tumor by using C6-TL transfectant cell line expressing HSV1-tk and firefly luciferase (fLuc), and then {gamma}-radiation was treated to xenografts locally. Treatment of {gamma}-radiation to primary C6-TL xenografts of mice reduced size of xenografts and elongated survival of mice than those of mock control mice. But we also show that {gamma}-radiation treatment was followed by the growth of dormant metastases in various organs including lung and intestine after 2-4 weeks of {gamma}-radiation treatment. When bioluminescence imaging indicated growth of tumor in organs in mice, we sacrificed the mice and repeat acquired bioluminescence imaging after repeatedly. These images presented tumor growth locations exactly in organs. Because metastatic tumor candidates have morphology of foci, biopsies were performed for histological analysis or PCR analysis to confirm metastases. In most foci, histological analysis indicated several features of typical cancer tissue and PCR analysis showed present of fLuc gene in metastases. Detection of fLuc gene in metastases indicated these foci were originated from primary C6-TL xenografts, and the results suggest that {gamma}-radiation could promote metastasis in vivo as well as in vitro system. Although we need to understand changes of intracellular signaling or physiological phenomena of the radiation-induced metastasis yet, these results also imply that {gamma}-radiation treatment only to cancer patients need to pay attention carefully, and development of new

  11. Radiation-induced malignant and atypical peripheral nerve sheath tumors

    International Nuclear Information System (INIS)

    The reported peripheral nerve complications of therapeutic irradiation in humans include brachial and lumbar plexus fibrosis and cranial and peripheral nerve atrophy. We have encountered 9 patients with malignant (7) and atypical (2) peripheral nerve tumors occurring in an irradiated site suggesting that such tumors represent another delayed effect of radiation treatment on peripheral nerve. In all instances the radio-theray was within an acceptable radiation dosage, yet 3 patients developed local radiation-induced skin and bony abnormalities. The malignant peripheral nerve sheath tumors developed only in the radiation port. Animal studies support the clinical observation that malignant peripheral nerve sheath tumors can occur as a delayed effect of irradiation

  12. Inducible HSP70 Protects Radiation-Induced Salivary Gland Damage

    International Nuclear Information System (INIS)

    Irradiation (IR) delivered to the head and neck is a common treatment for malignancies. Salivary glands in the irradiation field are severely damaged, and consequently this resulted in marked salivary hypofunction. While the exact mechanism of salivary gland damage remains enigmatic, fluid secreting acinar cells are lost, and saliva output is dramatically reduced. Previously we have reported that inducible heat shock protein 70 (HSP70i) induced radioresistance in vitro. Moreover, HSP70i localized to salivary glands by gene transfer has great potential for the treatment of salivary gland. Herein, we investigated whether HSP70 can use as radio protective molecules for radiation-induced salivary gland damage in vivo

  13. Use of radiation-induced polymers in cement slurries

    International Nuclear Information System (INIS)

    Water loss from cement slurries is reduced by incorporating within a cement slurry a polymer obtained as a product of radiation-induced polymerization of acrylamide and/or methacrylamide and acrylic acid, methacrylic acid, and/or alkali metal salts thereof. The polymerization is preferably carried out in 10-60 percent aqueous monomer solution with gamma radiation. The aqueous monomer solution preferably contains 25-99 percent acrylamide and 75-1 percent sodium acrylate. The polymer can be present in concentration of about 0.001 to about 3.0 weight percent, based on the aqueous phase of the slurry

  14. Use of radiation-induced polymers in cement slurries

    International Nuclear Information System (INIS)

    Water loss from cement slurries is reduced by incorporating within a cement slurry a polymer obtained as a product of radiation-induced polymerization of acrylamide and/or methacrylamide and acrylic acid, methacrylic acid, and/or alkali metal salts thereof. The polymerization is preferably carried out in 10 to 60 percent aqueous monomer solution with gamma radiation. The aqueous monomer solution preferably contains 25 to 99 percent acrylamide and 75 to 1 percent sodium acrylate. The polymer can be present in concentration of about 0.001 to about 3.0 weight percent, based on the aqueous phase of the slurry. (U.S.)

  15. 'Like new': plastic wastes regeneration by radiation induced grafting

    International Nuclear Information System (INIS)

    The reclaiming and the recycling of plastic wastes is made especially difficult when those wastes are a mixture of various plastics; this is due to the incompatibility of the polymers. The radiation induced grafting allows to overcome this incompatibility. Results are given which shows that, for various mixtures of reclaimed polyethylene, PVC and polystyrene, an improvement of the properties of the processed blends is obtained by grafting the mixtures of wastes by a suitable polymer; the obtained properties of those regenerated plastic blends are enough attractive from the technical point of view to open a market to those products with a reasonable economical value

  16. Sensitization of radiation-induced cell death by genistein

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Tae Rim; Kim, In Gyu [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2010-03-15

    A number of epidemiological studies as well as biological experiments, showed that genistein, one of the isoflavone, prevents prostate cancer occurrence. In this study, we showed that genistein inhibited the cell proliferation of human promyeoltic leukemia HL-60 cells and induced G2/M phase arrest. In addition, combination of genistein treatment and {gamma}-irradiation displayed synergistic effect in apoptotic cell death of HL-60 cells. This means that the repair of genistein-induced DNA damage was hindered by {gamma}-irradiation and thus cell death was increased. In conclusion, genistein is one of the important chemicals that sensitize radiation-induced cell death.

  17. Tissue culture regeneration and radiation induced mutagenesis in banana

    International Nuclear Information System (INIS)

    Radiation induced mutagenesis is an important tool for banana genetic improvement. At BARC, protocols for shoo-tip multiplication of commercial banana varieties have been developed and transferred to user agencies for commercial production. Excellent embryogenic cell suspensions were established in banana cvs. Rasthali and Rajeli, and were maintained at low temperatures for long-term storage. Normal plantlets were successfully regenerated from these cell suspensions. The cell suspensions and shoot-tip cultures were gamma-irradiated for mutagenesis. The mutagenized populations were field screened and a few interesting mutants have been isolated. The existence of genetic variation was confirmed using DNA markers. Further evaluation of these mutants is in progress. (author)

  18. Effect of electrodes in the radiation induced conductivity for polymers

    International Nuclear Information System (INIS)

    Samples of PET with 23 μm thickness were exposed to continuous X-rays and the radiation-induced conductivity (RIC) as a function of time were measured, using electrodes of evaporated aluminum and gold. The results showed that the use of higher atomic number metal electrodes increase the received dose rate by sample, without almost modifying the time evolution of the RIC or its dependence with the applied electric field intensity. It is also showed that this increase is caused by the electrode placed in the face of the sample where the radiation strikes, as well as by the one placed in the oposite face. (author)

  19. Chemical modification of polyurethanes by radiation-induced grafting

    International Nuclear Information System (INIS)

    Basic methods of radiation-induced modification of polyurethanes for biomedical applications and of their characterization are briefly described. The most important works found in literature on radiation grafting of polyurethanes are discussed. The radiation grafting of polyetherurethane films and tubings by the preswelling method using various monomers and their physico-chemical characterization are discussed in detail with respect to the antithrombogenic properties of the materials. Novel applications for radiation-modified polyurethanes as drug delivery systems or antiinfectious materials are briefly mentioned. 52 references

  20. RERF research agenda for studies of radiation-induced cancer

    International Nuclear Information System (INIS)

    In the last decade or so the numbers of cancers attributable to radiation among the Japanese A-bomb survivors have become large enough to permit quantitative estimates of risk and to encourage quantitative investigation of the many factors other than dose that appear to govern the appearance of radiation-induced cancer. The size and demographic complexity of the A-bomb survivor population are such that future studies should go far to provide the descriptive information on which our understanding of radiation carcinogenesis in man must ultimately depend. 60 references

  1. Quantitative analysis of radiation-induced disorder in spinel crystals

    International Nuclear Information System (INIS)

    Structural defects in the surface region of magnesium aluminate spinel (MgAl2O4) crystals irradiated with 450 MeV Xe ions were analyzed by using 4He backscattering in channeling geometry (RBS/C). Monte-Carlo simulations applied for the interpretation of channeling spectra permitted to determine the concentration of radiation-induced defects. They showed that the defect distributions are depth dependent, likely due to annihilation of defects at the surface of the crystals. The cross-section for the formation of defects by swift Xe ions, and consequently the diameter of an ion track, were estimated using single-impact-model calculations

  2. Transient radiation-induced absorption in laser materials

    Science.gov (United States)

    Brannon, Paul J.

    1994-06-01

    Transient radiation-induced absorption losses in laser materials have been measured using a pulsed nuclear reactor. Reactor pulse widths of 70 to 90 microsecond(s) and absorbed doses of 1 to 7.5 krad have been used. Transmission recovery times and peak absorption coefficients are given. Materials tested include LiNbO3, GSGG, silica substrates, and filter glasses used in the laser cavity. The filter glasses are tested at discrete wavelengths in the range 440 - 750 nm. Lithium niobate, MgO-doped LiNbO3, GSGG, and the silica substrates are tested at 1061 nm.

  3. Transient radiation-induced absorption in laser materials

    Energy Technology Data Exchange (ETDEWEB)

    Brannon, P.J.

    1994-12-31

    Transient radiation-induced absorption losses in laser materials have been measured using a pulsed nuclear reactor. Reactor pulse widths of 70 to 90 {mu}s and absorbed doses of 1 to 7.5 krad have been used. Transmission recovery times and peak absorption coefficients are given. Materials tested include LiNbO{sub 3}, GSGG, silica substrates, and filter glasses used in the laser cavity. The filter glasses are tested at discrete wavelengths in the range 440--750 nm. Lithium niobate , MgO doped LiNbO{sub 3}, GSGG, and the silica substrates are tested at 1061 nm.

  4. Surgery for radiation-induced carcinoma of the hypopharynx

    International Nuclear Information System (INIS)

    Eighteen radiation-induced tumors of the hypopharynx examined during a 20-year period are described. These tumors represent slightly less than 5 per cent of all tumors of the hypopharynx examined during the same period. Most were due to irradiation for thyrotoxicosis, and the mean latent period was 35 years. Five patients were not treated, and 13 patients were treated, mainly by pharyngolaryngectomy followed by skin flap repair (deltopectoral or pectoralis major). Despite a fairly high complication rate, an adjusted five-year survival of 35 per cent was achieved

  5. Radiation-induced cationic curing of vinyl ethers

    International Nuclear Information System (INIS)

    Recently there has been an increasing interest in nonacrylate radiation-curable coatings. Vinyl ethers are particularly reactive under cationic polymerization reaction conditions. The high efficiency of the photoacid initiators combined with the high reactivity of vinyl ether monomers makes this a potentially very useful system. This chapter discusses the preparation of vinyl ethers, introduces vinyl ether-functional monomers and oligomers, describes radiation-induced cationic polymerization of vinyl ethers, and discusses various coating systems. Throughout the chapter, an emphasis is placed on radiation-curable coating applications. 64 refs., 5 figs., 11 tabs

  6. Immobilization of yeast cells by radiation-induced polymerization

    International Nuclear Information System (INIS)

    Radiation-induced polymerization method was applied to the immobilization of yeast cells. The effects of irradiation, cooling and monomer, which are neccessary for polymerization, were recovered completely by subsequent aerobical incubation of yeast cells. The ethanol productive in immobilized yeast cells increased with the increase of aerobical incubation period. The growth of yeast cells in immobilized yeast cells was indicated. The maximum ethanol productivity in immobilized yeast cell system was around three times as much as that in free yeast cell system. (orig.)

  7. Does smoking protect against radiation-induced pneumonitis?

    International Nuclear Information System (INIS)

    The overall aim of the project reported here was to investigate the inflammatory reaction in the otherwise healthy human lung after ionizing irradiation. The tool used was the well accepted and now safe technique of bronchoalveolar lavage. The causality between smoking and the development of different forms of cancer, especially lung cancer, is well established. However, the possible effects of smoking on cancer treatment per se has been studied less. The authors observed, in addition to the expected inflammatory reactions in the lung parenchyma, that smoking during post-operative treatment of breast cancer seems to depress the grade of radiation-induced pneumonitis. (author)

  8. Ionizing Radiation Induces HMGB1 Cytoplasmic Translocation and Extracellular Release

    Institute of Scientific and Technical Information of China (English)

    Lili Wang; Li He; Guoqiang Bao; Xin He; Saijun Fan; Haichao Wang

    2016-01-01

    Objective A nucleosomal protein,HMGBI,can be secreted by activated immune cells or passively released by dying cells,thereby amplifying rigorous inflammatory responses.In this study we aimed to test the possibility that radiation similarly induces cytoplasmic HMGB1 translocation and release.Methods Human skin fibroblast (GM0639) and bronchial epithelial (16HBE) cells and rats were exposed to X-ray radiation,and HMGB1 translocation and release were then assessed by immunocytochemistry and immunoassay,respectively.Results At a wide dose range(4.0-12.0 Gy),X-ray radiation induced a dramatic cytoplasmic HMGB1 translocation,and triggered a time-and dose-dependent HMGB1 release both in vitro and in vivo.The radiation-mediated HMGB1 release was also associated with noticeable chromosomal DNA damage and loss of cell viability.Conclusions Radiation induces HMGB1 cytoplasmic translocation and extracellular release through active secretion and passive leakage processes.

  9. Radiation induced effects in the developing central nervous system

    International Nuclear Information System (INIS)

    The embryo and the human foetus are particularly sensitive to ionizing radiation and this sensitivity presents various qualitative and quantitative functional changes during intra-uterine development. Apart from radiation induced carcinogenesis, the most serious consequence of prenatal exposure in human beings is severe mental retardation. The principal data on radiation effects on human beings in the development of the central nervous system come form epidemiological studies carried out in individuals exposed in utero during the atomic explosion at Hiroshima and Nagasaki. These observations demonstrate the existence of a time of maximum radiosensitivity between the weeks 8 and 15 of the gestational period, a period in which the proliferation and neuronal migration takes place. Determination of the characteristics of dose-response relationship and the possible existence of a threshold dose of radiation effects on the development of the central nervous system is relevant to radiation protection against low dose radiation and the establishment of dose limits for occupational exposure and the public. Studies were conducted on the generation of nitrous-oxide and its relation with the production of active species of oxygen in brains of exposed rats in utero exposed to doses of up to 1 Gy during their maximum radiosensitivity. The possible role of the mechanism of radiation induced damage in the development of the central nervous system is discussed

  10. The thermal stability of radiation-induced defects in illite

    Science.gov (United States)

    Riegler, T.; Allard, T.; Beaufort, D.; Cantin, J.-L.; von Bardeleben, H. J.

    2016-01-01

    High-purity illite specimens from the Mesoproterozoic unconformity-related uranium deposits of Kiggavik, Thelon basin, Nunavut (Canada), and Shea Creek (Athabasca basin, Saskatchewan, Canada) have been studied using electron paramagnetic resonance spectroscopy to determine the thermal stability of the main radiation-induced defects and question the potential of using illite as a natural dosimeter. The observed spectra are complex as they can show in the same region several contributions: (1) an unstable native defect, (2) the main stable defect named Ai by reference to a previous study (Morichon et al. in Phys Chem Minerals 35:339-346, 2008), (3) a signal at g = 2.063 assigned to a new defect, not yet fully characterized, named Ai2 center and (4) impurities such as vanadyl complex or divalent manganese. Isochronal heating shows that the new signal corresponds to a stable species. Isothermal heating experiments at 400 and 450 °C provide values of half-life extrapolated at room temperature and activation energy of 1.9-29,109 years and 1.3-1.4 eV, respectively, corresponding to the Ai center. These parameters allow the use of stable radiation-induced defects as a record of radioactivity down to the Paleoproterozoic period.

  11. Simvastatin attenuates radiation-induced tissue damage in mice

    International Nuclear Information System (INIS)

    The aim of this study was to investigate the protective effect of simvastatin against radiation-induced tissue injury in mice. Mice were radiated with 4 Gy or 8 Gy after 20 mg/kg/d simvastatin treatment over 2 weeks. Morphological changes were observed in the jejunum and bone marrow, and apoptotic cells were determined in both tissues. Peripheral blood cells were counted, and the superoxide dismutase (SOD) activity and the malondialdehyde (MDA) level in tissues of both thymus and spleen were measured. Compared with the radiation-only group, 20 mg/kg/d simvastatin administration significantly increased the mean villi height and decreased apoptotic cells in jejunum tissue, and stimulated regeneration and reduced apoptotic cells in bone marrow. Peripheral blood cell analysis revealed that simvastatin treatment induced a larger number of red blood cells and increased the hemoglobin level present after 4 Gy of radiation. Interestingly, it was also found that the number of peripheral endothelial progenitor cells was markedly increased following simvastatin administration. Antioxidant determination for tissues displayed that simvastatin therapy increased the SOD activity after both 4 and 8 Gy of radiation, but only decreased the MDA level after 4 Gy. Simvastatin ameliorated radiation-induced tissue damage in mice. The radioprotective effect of simvastatin was possibly related to inhibition of apoptosis and improvement of oxygen-carrying and antioxidant activities. (author)

  12. Radiation induced segregation and point defects in binary copper alloys

    International Nuclear Information System (INIS)

    Considerable progress, both theoretical and experimental, has been made in establishing and understanding the influence of factors such as temperature, time, displacement rate dependence and the effect of initial solute misfit on radiation induced solute diffusion and segregation. During irradiation, the composition of the alloy changes locally, due to defect flux driven non-equilibrium segregation near sinks such as voids, external surfaces and grain boundaries. This change in composition could influence properties and phenomena such as ductility, corrosion resistance, stress corrosion cracking, sputtering and blistering of materials used in thermo-nuclear reactors. In this work, the effect of 1 MeV electron irradiation on the initiation and development of segregation and defect diffusion in binary copper alloys has been studied in situ, with the aid of a high voltage electron microscope. The binary copper alloys had Be, Pt and Sn as alloying elements which had atomic radii less than, similar and greater than that of copper, respectively. It has been observed that in a wide irradiation temperature range, stabilization and growth of dislocation loops took place in Cu-Sn and Cu-Pt alloys. Whereas in the Cu-Be alloy, radiation induced precipitates formed and transformed to the stable γ phase. (Author)

  13. Radiation-induced cationic polymerization of vinyl ethers in solution

    International Nuclear Information System (INIS)

    The influences of the polymerization media, the monomer and solvent concentrations and the temperature on the radiation-induced polymerization of isopropyl vinyl ether (IPVE) have been studied in detail under super-dry conditions. Rates of polymerization were measured and estimates of the rate constants of polymerization were calculated according to the simplified Hayashi-Williams equation. A comparison of the results with those previously reported for ethyl vinyl ether (EVE) is made. The much higher reactivity of IPVC in low polar solvents is interpreted by a drastic reduction of the polymer intramolecular solvation of the growing chain ends. This is ascribed to the bulkiness of the isopropyl side-chain groups. The radiation-induced polymerization of IPVE in bulk and in various solvents with different physical and solvating properties was studied. This was to obtain further information on the kinetics and the mechanisms involved with this monomer and also the role of the polymerization media. The influence of the monomer and solvent concentrations and of the polymerization temperature on the rate of polymerization have also been investigated. (author)

  14. Radiation-induced cataracts. Glance at some new data

    International Nuclear Information System (INIS)

    The radiation-induced cataract has been up to now considered as a quite rare pathology, needing high-dose radiations (beyond a dose threshold roughly estimated at 2 Grays to the lens) consisting mainly in head tumour radiotherapy complications. Several new studies on different exposed populations such as astronauts, Japanese atomic bomb survivors, people undergoing X-ray examinations, Chernobyl accident 'liquidators' as well as data from animal experiments, suggest that dose threshold for detectable opacities as well as for clinical posterior sub-capsular cataract occurring, might be far lower than those previously assumed. Even the existence of a dose threshold is no longer an absolute certitude insofar as radiation-induced cataract pathogenesis might consist not really in a deterministic effect (direct tissue harmful effect, killing or seriously injuring a critical population of cells) as believed until now, but rather in a stochastic effect (genomic damage in target-cells, altered cell division, abnormal lens fibre cell differentiation). More practically, these new data may lead us to reconsider radioprotection of specifically exposed populations : mainly patients and workers. Regarding workers, labour legislation (lens equivalent dose limit of 150 mSv during 12 consecutive months) might be, in the medium term, reassessed downwards. (author)

  15. Neurolysis and myocutaneous flap for radiation induced brachial plexus neuropathy

    International Nuclear Information System (INIS)

    Surgical treatment for radiation induced brachial plexus neuropathy is difficult. We followed 9 patients of radiation induced brachial plexus neuropathy who were surgically treated with neurolysis and myocutaneous flap coverage. Their ages ranged from 29 to 72 years old. Their diagnoses were breast cancer in 6 patients, lingual cancer in 1, thyroid cancer in 1 and malignant lymphoma in 1. Total dose of radiation ranged from 44 to 240 Gy. Interval from radiation therapy to our surgery ranged from 1 to 18 years (mean 6.7 years). Chief complaints were dysesthesia in 9 patients, motor weakness in 7 patients and dullach in scar formation of radiated skin in 7 patients. Preoperative neural functions were slight palsy in 1, moderate palsy in 5 and complete palsy in 3. In surgical treatment, neurolysis of the brachial plexus was done and it was covered by latissimus dorsi myocutaneous flap. We evaluated about dysesthesia and motor recovery after treatment for neuropathy. Follow up periods ranged from 1 to 11 years (average in 5 years). Dysesthesia improved in 6 patients and got worse in 3 patients. Motor weakness recovered in only 2 patients and got worse in 7 patients. From our results, intolerable dysesthesia which was first complaint of these patients improved. But motor function had not recovered. Our treatment was thought to be effective for extraneural factor like an compression neuropathy by scar formation and poor vascularity. But it was not effective for intraneural damage by radiation therapy. (author)

  16. Neurolysis and myocutaneous flap for radiation induced brachial plexus neuropathy

    Energy Technology Data Exchange (ETDEWEB)

    Hirachi, Kazuhiko; Minami, Akio; Kato, Hiroyuki; Nishio, Yasuhiko [Hokkaido Univ., Sapporo (Japan). School of Medicine; Ohnishi, Nobuki

    1998-11-01

    Surgical treatment for radiation induced brachial plexus neuropathy is difficult. We followed 9 patients of radiation induced brachial plexus neuropathy who were surgically treated with neurolysis and myocutaneous flap coverage. Their ages ranged from 29 to 72 years old. Their diagnoses were breast cancer in 6 patients, lingual cancer in 1, thyroid cancer in 1 and malignant lymphoma in 1. Total dose of radiation ranged from 44 to 240 Gy. Interval from radiation therapy to our surgery ranged from 1 to 18 years (mean 6.7 years). Chief complaints were dysesthesia in 9 patients, motor weakness in 7 patients and dullach in scar formation of radiated skin in 7 patients. Preoperative neural functions were slight palsy in 1, moderate palsy in 5 and complete palsy in 3. In surgical treatment, neurolysis of the brachial plexus was done and it was covered by latissimus dorsi myocutaneous flap. We evaluated about dysesthesia and motor recovery after treatment for neuropathy. Follow up periods ranged from 1 to 11 years (average in 5 years). Dysesthesia improved in 6 patients and got worse in 3 patients. Motor weakness recovered in only 2 patients and got worse in 7 patients. From our results, intolerable dysesthesia which was first complaint of these patients improved. But motor function had not recovered. Our treatment was thought to be effective for extraneural factor like an compression neuropathy by scar formation and poor vascularity. But it was not effective for intraneural damage by radiation therapy. (author)

  17. Allopurinol gel mitigates radiation-induced mucositis and dermatitis

    International Nuclear Information System (INIS)

    It has not been verified whether allopurinol application is beneficial in decreasing the severity of radiation-induced oral mucositis and dermatitis. Rats were divided into 4 groups and received 15 Gy irradiation on the left whisker pad. Group 1 received only irradiation. Group 2 was maintained by applying allopurinol/carrageenan-mixed gel (allopurinol gel) continuously from 2 days before to 20 days after irradiation. Group 3 had allopurinol gel applied for 20 days after radiation. Group 4 was maintained by applying carrageenan gel continuously from 2 days before to 20 days after irradiation. The intra oral mucosal and acute skin reactions were assessed daily using mucositis and skin score systems. The escape thresholds for mechanical stimulation to the left whisker pad were measured daily. In addition, the irradiated tissues at the endpoint of this study were compared with naive tissue. Escape threshold in group 2 was significantly higher than that in group 1, and mucositis and skin scores were much improved compared with those of group 1. Concerning escape threshold, mucositis and skin scores in group 3 began to improve 10 days after irradiation. Group 4 showed severe symptoms of mucositis and dermatitis to the same extent as that observed in group 1. In the histopathological study, the tissues of group 1 showed severe inflammatory reactions, compared with those of group 2. These results suggest that allopurinol gel application can mitigate inflammation reactions associated with radiation-induced oral mucositis and dermatitis. (author)

  18. Radiation-induced muscositis and neutrophil granulocytes in oral mucosa

    International Nuclear Information System (INIS)

    Background: Chemotherapy-induced mucositis can be related to a decrease in oral neutrophils. We tested the relationship between radiation-induced mucositis and oral neutrophil counts. Patients and Methods: Oral neutrophil counts were obtained for ten patients with head and neck cancer who received radiotherapy of the pharynx and oral cavity. Four patients received additional chemotherapy (5-FU, Mitomycin). Counts were obtained before and during treatment; four healthy volunteers were included in the study as well. For evaluation, a quantitative mouth rinse assay, including neutrophil-staining with acridin-orange, was applied. Results: We observed large inter-individual variations with respect to neutrophil counts for patients and control persons (Table 1). During treatment (irradiation or chemoirradiation), large intra-individual variations were seen additionally (Figure 1). We found a correlation between neutrophil counts and clinical reaction grade. Neutrophil counts increased with increasing mucositis (Figure 2). This increase was more pronounced for patients treated with chemoirradiation compared to radiation alone. Treatment breaks at weekends had no clear influence on neutrophil counts. Conclusions: We observed a weak correlation between neutrophil counts and clinical reaction grade. However, the variations in neutrophil counts are too large to utilize this parameter as a surrogate for clinical mucositis grading. The assumption that a decrease in oral neutrophils is associated with radiation-induced mucositis was clearly negated. (orig.)

  19. Radiation-induced segregation in Cu-Au alloys

    International Nuclear Information System (INIS)

    Radiation-induced segregation in a Cu-1 at. % Au alloy was investigated using in situ Rutherford Backscattering Spectrometry. Irradiation with 1.8-MeV He produced nonequilibrium Au atom depletion in the near surface region. The amount of segregation was measured as a function of dose, dose rate and temperature. Segregation was observed between 300 and 5000C. For a calculated dose rate of 3.9 x 10-5 dpa/s, the radiation-induced segregation rate peaked near 4000C. Theoretical analysis based on the Johnson-Lam model predicted that the amount of segregation would be directly proportional to dose at the early stage of irradiation, would deviate from linearity with a continuously decreasing slope at intermediate doses, and finally approach a constant value after high doses. The analysis also predicted that the segregation rate would vary as the -1/4th power of the dose rate at constant dose in the low temperature region. These predictions were all verified experimentally. A procedure for extracting relative defect production efficiencies from similar measurements is discussed

  20. Characterization of radiation-induced emesis in the ferret

    Energy Technology Data Exchange (ETDEWEB)

    King, G.L.

    1988-06-01

    Forty-eight ferrets (Mustela putorius furo) were individually head-shielded and radiated with bilateral /sup 60/Co gamma radiation at 100 cGy min-1 at doses ranging between 49 and 601 cGy. The emetic threshold was observed at 69 cGy, the ED50 was calculated at 77 cGy, and 100% incidence of emesis occurred at 201 cGy. With increasing doses of radiation, the latency to first emesis after radiation decreased dramatically, whereas the duration of the prodromal period increased. Two other sets of experiments suggest that dopaminergic mechanisms play a minor role in radiation-induced emesis in the ferret. Twenty-two animals were injected either intravenously or subcutaneously with 30 to 300 micrograms/kg of apomorphine. Fewer than 50% of the animals vomited to 300 micrograms/kg apomorphine; central dopaminergic receptor activation was apparent at all doses. Another eight animals received 1 mg/kg domperidone prior to either 201 (n = 4) or 401 (n = 4) cGy radiation and their emetic responses were compared with NaCl-injected-irradiated controls (n = 8). At 201 cGy, domperidone significantly reduced only the total time in emetic behavior. At 401 cGy, domperidone had no salutary effect on radiation-induced emesis. The emetic responses of the ferret to radiation and apomorphine are compared with these responses in other vomiting species.

  1. Characterization of radiation-induced emesis in the ferret

    Energy Technology Data Exchange (ETDEWEB)

    King, G.L.

    1988-01-01

    Forty-eight ferrets (Mustela putorius furo) were individually head-shielded and radiated with bilateral cobalt 60 gamma radiation at 100 cGy min at doses ranging between 49 and 601 cGy. The emetic threshold was observed at 69 cGy, the ED 50 was calculated as 77 cGy, and 100% incidence of emesis occurred at 201 cGy. With increasing doses of radiation, the latency to first emesis after radiation decreased dramatically, whereas the duration of the prodromal period increased. Two other sets of experiments suggest that dopaminergic mechanisms play a minor role in radiation-induced emesis in the ferret. Twenty-two animals were injected either intravenously or subcutaneously with 30 to 300 micrograms /kg of apomorphine. Fewer than 50% of the animals vomited to 300 micrograms/kg apomorphine; central dopaminergic receptor activation was apparent at all doses. Another eight animals received 1 mg/kg domperidone prior to either 201 (n=4) or 401 (n=4) cGy radiation and their emetic responses were compared with NaCi-injected-irradiated controls (n=8). At 201 cGy, domperidone significantly reduced only the total time in emetic behavior. At 401 cGy, domperidone had no salutary effect on radiation-induced emesis. The emetic responses of the ferret to radiation and apomorphine are compared with these responses in other vomiting species.

  2. Radiation-induced grafting of styrene on polypropylene pellets

    International Nuclear Information System (INIS)

    The changes of radiation-induced in polypropylene (PP) pellets exposed to gamma irradiation in inert atmosphere were investigated in correlation with the applied doses (10 and 50 kGy). Also, results from the grafting of styrene onto PP pellets using simultaneous irradiation at the same doses are presented. The grafting reaction was carried out using toluene as solvent, under nitrogen atmosphere and at room temperature. The properties of the irradiated and grafted PP pellets were studied using Melt Flow Index, thermal analysis (TG and DSC), and ATR-IR. The degree of grafting (DOG) for the grafted pellets was gravimetrically determined. The results showed that radiation-induced graft polymerization on pellets were successfully obtained and the influence of dose irradiated did not change the thermal properties in spite of the increase in the MFI and consequently this increase in the viscosity results an decrease the molecular mass. The MFI for grafted pellets was not achievable because the high degree of viscosity of polymer, even arising the test temperature, the polymer was not flow enough. (author)

  3. ROS Mediates Radiation-Induced Differentiation in Human Lung Fibroblast

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sa Rah; Ahn, Ji Yeon; Kim, Mi Hyeung; Lim, Min Jin; Yun, Yeon Sook; Song, Jie Young [Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of)

    2009-05-15

    One of the most common tumors worldwide is lung cancer and the number of patients with lung cancer received radiotherapy is increasing rapidly. Although radiotherapy may have lots of advantages, it can also induce serious adverse effects such as acute radiation pneumonitis and pulmonary fibrosis. Pulmonary fibrosis is characterized by excessive production of smooth muscle actin-alpha (a-SMA) and accumulation of extracellular matrix (ECM) such as collagen and fibronectin. There has been a great amount of research about fibrosis but the exact mechanism causing the reaction is not elucidated especially in radiation-induced fibrosis. Until now it has been known that several factors such as transforming growth factor (TGF-b), tumor necrosis factor (TNF), IL-6, platelet-derived growth factor (PDGF) and reactive oxygen species are related to fibrosis. It is also reported that reactive oxygen species (ROS) can be induced by radiation and can act as a second messenger in various signaling pathways. Therefore we focused on the role of ROS in radiation induced fibrosis. Here, we suggest that irradiation generate ROS mainly through NOX4, result in differentiation of lung fibroblast into myofibroblast.

  4. Nature of radiation-induced defects in quartz

    International Nuclear Information System (INIS)

    Although quartz (α-form) is a mineral used in numerous applications wherein radiation exposure is an issue, the nature of the atomistic defects formed during radiation-induced damage has not been fully clarified. Especially, the extent of oxygen vacancy formation is still debated, which is an issue of primary importance as optical techniques based on charged oxygen vacancies have been utilized to assess the level of radiation damage in quartz. In this paper, molecular dynamics simulations are applied to study the effects of ballistic impacts on the atomic network of quartz. We show that the defects that are formed mainly consist of over-coordinated Si and O, as well as Si–O connectivity defects, e.g., small Si–O rings and edge-sharing Si tetrahedra. Oxygen vacancies, on the contrary, are found in relatively low abundance, suggesting that characterizations based on E′ centers do not adequately capture radiation-induced structural damage in quartz. Finally, we evaluate the dependence on the incident energy, of the amount of each type of the point defects formed, and quantify unambiguously the threshold displacement energies for both O and Si atoms. These results provide a comprehensive basis to assess the nature and extent of radiation damage in quartz

  5. Optical bleaching of radiation-induced colour centres in fluorapatite

    International Nuclear Information System (INIS)

    One of the important steps in thermoluminescence (TL) dating studies is the assessment of the total natural radiation dose that a sample has received and retained. This, in turn, depends on the thermal and temporal stabilities as well as the optical bleaching of the radiation-induced colour centres. In this paper, we report the effect of selective optical bleaching, after X-irradiation, on the TL glow curves of synthetic fluorapatite. X-irradiated fluorapatite exhibits three unresolved TL peaks around 150, 250 and 345 C. Diffuse reflectance studies of the polycrystalline fluorapatite show that X-irradiation induces absorption bands at 370 and 450 nm. Furthermore, exposure to light through 320 to 400 nm and 400 to 480 nm band filters effectively bleaches the TL glow from the first two peaks at around 150 and 250 C. By correlating the wavelength of light used for bleaching the TL with the radiation-induced absorption bands, the type of centres involved in the approx. 150 C TL glow peak in fluorapatite has been identified as E(II) or A centres, i.e. halogen ion vacancies with trapped electrons. Although the approx. 250 C TL glow peak is also bleached along with the 150 C TL peak, its temperature stability does not agree with that of the A centres. (author)

  6. Radiation induced effects and annealing methods in fiberoptics and glasses

    International Nuclear Information System (INIS)

    Radiation induced effects in glass-rods and fiberoptics have been studied to determine parameters affecting the application of these materials in nuclear technology, i.e. as fiberscopes for visual inspection in severe radiation environments. Different glass and fibertypes have been exposed to fission product gamma radiation. The radiation induced transmission loss was measured with a spectrophotometer and then different annealing methods were examined to improve the transmission properties again. Especially the changes in glass and fiber recovery vs. time as a function of radiation dose and annealing temperature were investigated. Annealing experiments were performed exposing the samples either to temperature treatment or to various light sources such as quartz lamp, arc lamp or UV-laser for optical annealing. The transmission recovery was then investigated either as a function of annealing temperature or of exposure time to the light sources. The results allow conclusions on the design and composition of optical fiber endoscopes to be used in severe radiation environment where image transmission is required in the presence of high level nuclear radiation. (author)

  7. Hyperbaric oxygen therapy for radiation-induced hemorrhagic cystitis

    International Nuclear Information System (INIS)

    Hyperbaric oxygen (HBO) therapy has recently emerged as a potential primary option for the management of hemorrhagic cystitis. We review our experience treating hemorrhagic cystitis with HBO. Between January 2001 and May 2007, eight patients with radiation-induced hemorrhagic cystitis underwent HBO therapy. There were five men and three women with a mean age of 64.3 years (47-73). Radiation was given for local disease, and the mean dosage delivered was 56.6 Gy (42-70). The mean duration between the onset of hematuria and the beginning of HBO therapy was 8.9 months (3-34). Mean follow-up period was 15.5 months (2-31). Hematuria resolved completely in six of the eight patients, one of whom suffered recurrence of hematuria and was treated with HBO until the hematuria resolved again. The response rate was 75%, compatible with the previous reports, and no side-effects of HBO were noted. HBO treatment should be attempted for radiation-induced hemorrhagic cystitis. (author)

  8. The redox homeostasis system in radiation-induced genome instability

    International Nuclear Information System (INIS)

    The participation of the redox homeostasis system in the formation of the radiation-induced genome instability and new data of literature, that give a direct evidence the presence of this instability in vivo, is considered. The O2- radical, H2O2 and NO radical role as signal molecules, that trigger the cascade of active responses to change of redox status of the cells, are discussed. The reactive oxygen species (ROS) reorganize the membrane physico-chemical system of cell metabolism regulation. The data about changes in ROS generation system, including NO, that lead to genome instability after ionizing irradiation even in low doses, are analyzed. It is noted, that the radiation-induced genome instability and ROS production increase may be observed both in direct irradiated cells and their progeny and in the cells, that are not find oneself in ionization tracks, and their progeny. There evidences that the genome instability of irradiated cell progeny is maintained by the increases ROS production

  9. Radiation-induced electron migration in nucleic acids

    International Nuclear Information System (INIS)

    Radiation-induced electron migration along DNA is a mechanism by which randomly produced stochastic energy deposition events can lead to non-random types of damage along DNA manifested distal to the sites of the initial energy deposition. Radiation-induced electron migration in nucleic acids has been examined using oligonucleotides containing 5-bromouracil (5-BrU). Interaction of 5-BrU with solvated electrons results in release of bromide ions and formation of uracil-5-yl radicals. Monitoring either bromide ion release or uracil formation provides an opportunity to study electron migration processes in model nucleic acid systems. Using this approach we have discovered that electron migration along oligonucleotides is significantly influenced by the base sequence and strandedness. Migration along 7 base pairs in oligonucleotides containing guanine bases was observed for oligonucleotides irradiated in solution, which compares with mean migration distances of 6-10 bp for Escherichia coli DNA irradiated in solution and 5.5 bp for E. coli DNA irradiated in cells. Evidence also suggests that electron migration can occur preferentially in the 5' to 3' direction along a double-stranded oligonucleotide containing a region of purine bases adjacent to the 5-BrU moiety. Our continued efforts will provide information regarding the contribution of electron transfer along DNA to formation of locally multiply damaged sites created in DNA by exposure to ionizing radiation. (Author)

  10. Protection from ionizing radiation induced damages by phytoceuticals and nutraceuticals

    International Nuclear Information System (INIS)

    Exposure of living systems to ionizing radiation cause a variety of damages to DNA and membranes due to generation of free radicals and reactive oxygen species. The radiation induced lesions in the cellular DNA are mainly strand breaks, damage to sugar moiety, alterations and elimination of bases, cross links of the intra and inter strand type and cross links to proteins while peroxidation of the lipids and oxidation of proteins constitute the major lesions in the membranes. The radioprotectors elicit their action by various mechanisms such as i) by suppressing the formation of reactive species, ii) detoxification of radiation induced species, iii) target stabilization and iv) enhancing the repair and recovery processes. The radioprotective compounds are of importance in medical, industrial, environmental, military and space science applications. Radiation protection might offer a tactical advantage on the battlefield in the event of a nuclear warfare. Radioprotectors might reduce the cancer risk to populations exposed to radiations directly or indirectly through industrial and military applications. The antioxidant and radioprotective properties a few of these agents under in vitro and in vivo conditions in animal models will be discussed

  11. Inhibition of radiation-induced polyuria by histamine receptor antagonists

    International Nuclear Information System (INIS)

    In previous studies the authors have demonstrated that gamma radiation results in polyuria, which is preceded by polydypsia. This suggests that the increased thirst elicited by radiation causes increased urinary volume (UV). Histamine, which is released following radiation exposure, also elicits drinking by nonirradiated rats when administered exogenously. In this study the authors have investigated both the role of water deprivation and the effect of histamine receptor antagonists (HRA) on radiation-induced polyuria. Sprague-Dawley rats were housed individually in metabolic cages. Water was allowed ad libitum except in deprivation experiments where water was removed for 24 hr immediately following radiation. Cimetidine (CIM), an H2 HRA, and dexbromopheniramine (DXB), an H1 HRA, were administered i.p. (16 and 1 mg/kg, respectively) 30 min prior to irradiation (950 rads from a cobalt source). UV was determined at 24-hr intervals for 3 days preceding irradiation and 24 hr postirradiation. UV in DXB treated rats was significantly reduced 24 hr postirradiation (CON = 427 +/- 54%; DXB = 247 +/- 39% of preirradiated CON) compared to postirradiation control values. CIM did not affect postirradiation UV. These data suggest that radiation-induced polyuria is caused by polydypsia which is, in part, mediated by histamine induced by an H1 receptor

  12. Ionizing radiation induced conductivity in Mylar (PET) and Kapton (Polyimide)

    International Nuclear Information System (INIS)

    The extensive results of measurements of the prompt and delayed radiation-induced conductivity of samples of PET and Kapton are presented. Experimental parameters, such as the effective energy of the radiation, the exposure rate, the total dose, the value of the applied electric field, the nature of the electrodes, and the ambiental conditions were changed within wide limits. We also report measurement of thermally stimulated currents for non-irradiated and for irradiated samples which allowed us to investigate the trap-structure of the materials. Measurements of photo-Compton currents with different electrode materials and sample thicknesses gave information about the relation between the nature of the electrodes and the amplitudes of the currents. Based on the generalized rate theory of radiation-induced conduction we developed a theoretical model which includes the effect of the applied electric field on the carrier generation yield (geminate recombination, Onsager effect). Comparison of experimental and theoretical curves allowed us to determine the values of the main conduction parameters, such as carrier mobility, recombination coefficient, trap densities, for the materials under investigation. (Author)

  13. Radiation-induced mucositis pain in laryngeal cancer

    International Nuclear Information System (INIS)

    Radiation therapy in those with head and neck malignancies often triggers painful mucositis poorly controlled by nonsteroidal antiinflammatory drugs (NSAIDs). To better understand how radiation-induced pain develops over time, we studied the numerical rating scale (NRS 0-5) pain scores from 32 persons undergoing radiation therapy of 60-72 Gy for newly diagnosed laryngeal cancer. The degree of mucositis was evaluated using Common Terminology Criteria for Adverse Events version3.0 (CTCAE v3.0). We divided the 32 into a conventional fractionation (CF) group of 14 and a hyperfractionation (HF) group of 18, and further divided laryngeal cancer into a small-field group of 23 and a large-field group of 9. The mucositis pain course was similar in CF and HF, but mucositis pain was severer in the HF group, which also required more NSAIDs. Those in the large-field group had severer pain and mucositis and required more NSAIDs than those in the small-field group. We therefore concluded that small/large-field radiation therapy, rather fractionation type, was related to the incidence of radiation-induced mucositis pain. (author)

  14. Perbedaan Laju Aliran Saliva Sebelum dan Sesudah Mengunyah Permen Karet Xylitol® pada Penderita Diabetes Melitus Tipe 2 dengan Xerostomia di RSUP Haji Adam Malik Medan

    OpenAIRE

    Fauzi, Miranda Purnama Sari

    2015-01-01

    Diabetes melitus (DM) merupakan suatu kelompok penyakit metabolik dengan karakteristik hiperglikemia yang terjadi karena kelainan sekresi insulin, kerja insulin atau kedua-duanya.Diabetes melitus dapat menyebabkan berbagai komplikasi oral. Salah satu komplikasi yang umum terjadi adalah mulut kering (xerostomia). Perawatan xerostomia dapat dilakukan dengan cara stimulasi lokalyaitu dengan mengunyah permen karet. Tujuan penelitian ini adalah untuk mengetahui perbedaan laju aliran saliva sebelum...

  15. Mechanism of enhancement of radiation-induced cytotoxicity by sorafenib in colorectal cancer

    OpenAIRE

    Kim, Yong Bae; Jeung, Hei-Cheul; Jeong, Inhye; Lee, KyungHwa; Rha, Sun Young; Chung, Hyun Cheol; Kim, Gwi Eon

    2012-01-01

    Sorafenib, an orally available multikinase inhibitor, combined with radiation has shown potential as an anticancer treatment in an in vitro and in vivo colon cancer model. In this study, we investigated the mechanism of enhancement of radiation-induced cytotoxicity by sorafenib in colorectal cancer. The effects of sorafenib on radiation-induced cytotoxicity of DLD-1 and HT-29 were evaluated via clonogenic assay. The impact of sorafenib on radiation-induced cell cycle kinetics and on apoptosis...

  16. Effect of pH on radiation-induced apoptosis

    International Nuclear Information System (INIS)

    Purpose/Objective: The effect of environmental pH on the radiation-induced apoptosis in tumor cells in vitro was investigated. Materials and Methods: SCK mammary adenocarcinoma cells of A/J mice were irradiated with γ-rays using a 137Cs irradiator and incubated in media of different pHs. After incubation at 37 degree sign C for 24-120 hrs., the extent of apoptosis was determined using agarose gel electrophoresis of DNA, in situ TUNEL staining, flow cytometry, and release of 3H from 3H-thymidine labeled cells. The membrane integrity, using the trypan blue exclusion method, and the clonogenicity of the cells were also determined. Results: Irradiation with 2-12 Gy of γ-rays induced apoptosis in pH 7.5 medium within 48 hrs. The radiation-induced apoptosis progressively declined as the medium pH was lowered so that little apoptosis occurred in 48 hrs. after irradiation with 12 Gy in pH 6.6 medium. However, when the cells were irradiated and incubated for 48 hrs. in pH 6.6 medium and then medium was replaced with pH 7.5 medium, apoptosis promptly occurred. Apoptosis also occurred even in pH 6.6 medium when the cells were irradiated and maintained in pH 7.5 medium for 8 hrs. or longer post-irradiation before incubation in pH 6.6 medium. Conclusion: An acidic environment markedly suppresses radiation-induced apoptosis probably by suppressing the expression of initial signals responsible for irradiation-induced apoptosis. Indications are that the signals persist in an acidic environment and trigger apoptosis when the environmental acidity is eased. Our results suggest that the acidic environment in human tumors may inhibit the apoptosis after irradiation. However, apoptosis may be triggered when reoxygenation occurs after irradiation, and thus, the intratumor environment becomes less acidic after irradiation. Not only the change in pO2 but the change in pH during the course of fractionated radiotherapy may greatly influence the outcome of the treatment

  17. Image guidance during breast radiotherapy: a phantom dosimetry and radiation-induced second cancer risk study

    Science.gov (United States)

    Quinn, A.; Holloway, L.; Metcalfe, P.

    2013-06-01

    Imaging procedures utilised for patient position verification during breast radiotherapy can add a considerable dose to organs surrounding the target volume on top of therapeutic scatter dose. This study investigated the dose from a breast kilovoltage cone-beam CT (kV-CBCT), a breast megavoltage fan-beam CT (MV-FBCT), and a TomoDirectTM breast treatment. Thermoluminescent dosimeters placed within a female anthropomorphic phantom were utilised to measure the dose to various organs and tissues. The contralateral breast, lungs and heart received 0.40 cGy, 0.45 cGy and 0.40 cGy from the kV-CBCT and 1.74 cGy, 1.39 cGy and 1.73 cGy from the MV-FBCT. In comparison to treatment alone, daily imaging would increase the contralateral breast, contralateral lung and heart dose by a relative 12%, 24% and 13% for the kV-CBCT, and 52%, 101% and 58% for the MV-FBCT. The impact of the imaging dose relative to the treatment dose was assessed with linear and linear-quadratic radiation-induced secondary cancer risk models for the contralateral breast. The additional imaging dose and risk estimates presented in this study should be taken into account when considering an image modality and frequency for patient position verification protocols in breast radiotherapy.

  18. Polymers under ionizing radiation: the study of energy transfers to radiation induced defects

    International Nuclear Information System (INIS)

    Radiation-induced defects created in polymers submitted to ionizing radiations, under inert atmosphere, present the same trend as a function of the dose. When the absorbed dose increases, their concentrations increase then level off. This behavior can be assigned to energy transfers from the polymer to the previously created macromolecular defects; the latter acting as energy sinks. During this thesis, we aimed to specify the influence of a given defect, namely the trans-vinylene, in the behavior of polyethylene under ionizing radiations. For this purpose, we proposed a new methodology based on the specific insertion, at various concentrations, of trans-vinylene groups in the polyethylene backbone through chemical synthesis. This enables to get rid of the variety of created defects on one hand and on the simultaneity of their creation on the other hand. Modified polyethylenes, containing solely trans-vinylene as odd groups, were irradiated under inert atmosphere, using either low LET beams (gamma, beta) or high LET beams (swift heavy ions). During irradiations, both macromolecular defects and H2 emission were quantified. According to experimental results, among all defects, the influence of the trans-vinylene on the behavior of polyethylene is predominant. (author)

  19. Evaluation of Xerostomia and salivary flow rate in Hashimoto’s Thyroiditis

    OpenAIRE

    Agha-Hosseini, Farzaneh; Shirzad, Nooshin; Moosavi, Mahdieh Sadat

    2016-01-01

    Background One of the most common causes of hypothyroidism is Hashimoto´s Thyroiditis (HT). Early detection of dry mouth is critical in preserving and promoting systemic and oral health. In this study we have assessed, for the first time, salivary function and xerostomia in HT patients who have not been involved with Sjögren´s syndrome. Material and Methods HT was diagnosed in 40 patients based on clinical findings and positive anti-thyroid peroxidase antibodies (anti-TPO). Controls, matched ...

  20. Radiatively induced breaking of conformal symmetry in a superpotential

    Science.gov (United States)

    Arbuzov, A. B.; Cirilo-Lombardo, D. J.

    2016-07-01

    Radiatively induced symmetry breaking is considered for a toy model with one scalar and one fermion field unified in a superfield. It is shown that the classical quartic self-interaction of the superfield possesses a quantum infrared singularity. Application of the Coleman-Weinberg mechanism for effective potential leads to the appearance of condensates and masses for both scalar and fermion components. That induces a spontaneous breaking of the initial classical symmetries: the supersymmetry and the conformal one. The energy scales for the scalar and fermion condensates appear to be of the same order, while the renormalization scale is many orders of magnitude higher. A possibility to relate the considered toy model to conformal symmetry breaking in the Standard Model is discussed.

  1. An integrated model for radiation induced cancer (IMRIC)

    International Nuclear Information System (INIS)

    The ultimate aim for radiation induced cancer modeling must be to arrive at cancer risk estimates in the human, based (partly or entirely) on data obtained in the laboratory. Current risk estimates for the stochastic radiation effect of cancer induction derive entirely from epidemiological data, largely of the Japanese survivors of the A-bombs, with little input of laboratory information. These data relate to high doses and high dose-rates and it is difficult to see how much more information can be extracted from them. Because of rapid progress in many fields, including molecular biology, cellular studies and experiments with laboratory animals, it is argued here that the time is now ripe for an attempt to be made to model the entire sequence of events from the absorption of radiation energy to the manifestation of a malignancy in the human. (author)

  2. Radiation-induced degradation of 4-chloroaniline in aqueous solution

    International Nuclear Information System (INIS)

    The radiation-induced decomposition of 4-chloroaniline (4-ClA) was studied under steady-state conditions using aqueous solutions saturated with air, pure oxygen, N2O, argon and argon in the presence of t-Butanol. Using HPLC-method, the initial G-values of the substrate degradation as well as of a number of radiolytic products were determined. The formation of aminophenols, chlorophenols, aniline and phenol in addition to chloride, ammonia, formaldehyde and mixture of aldehydes as well as carboxylic acids was studied as a function of absorbed dose. Based on the experimental data, probable reaction mechanisms for the degradation of 4-ClA by γ-rays and the formation of the identified products are presented

  3. Radiation-induced coronary artery disease. One observation

    International Nuclear Information System (INIS)

    Twenty-seven reports (26 from the literature) of radiation ischemic heart diseases are studied in order to specify their clinical and pathological findings and their natural history. This complications appear after treatment of radiation-curable diseases with a mean delay of 4 years in young patients (mean age of 31). Several coronary arteries are often injuried with fibrous and or atherosclerotic anatomical lesions. The frequency of this coronary artery diseases is certainly more important than reported since they are often latent but probably progressive. However, atherogenetic factors increase the risk and must be lowered in a preventive aim; as a rule, the radiotherapic technique must also be as perfect as possible. The prognosis of this radiation induced coronary artery diseases is poor: 19 myocardial infarctions and 12 deaths are observed but no cardiac death occured in patients who received a by-pass graft. So, radiation ischemic heart disease needs active investigation and therapy

  4. Binding of radiation-induced phenylalanine radicals to DNA

    International Nuclear Information System (INIS)

    When an aqueous solution of double-stranded DNA of bacteriophage PM2 containing phenylalanine and saturated with N2O is irradiated with γ-rays, radiation-induced phenylalanine radicals are bound covalently. Under the conditions used about 25 phenylalanine molecules may be bound per lethal hit. Also for single-stranded PM2 DNA, most of the phenylalanine radicals bound are non-lethal. Evidence is presented that in double-stranded DNA an appreciable fraction of the single-strand breaks is induced by phenylalanine radicals. Radiation products of phenylalanine and the phenylalanine bound to the DNA decrease the sensitivity of the DNA to the induction of single-strand breaks. There are indications that the high efficiency of protection by radiation products of phenylalanine is due to their positive charge, which will result in a relatively high concentration of these compounds in the vicinity of the negatively charged DNA molecules

  5. HSP25 Protects Radiation-Induced Salivary Gland Damage

    International Nuclear Information System (INIS)

    Irradiation (IR) is a central treatment modality administered for head and neck malignancies. A significant consequence of this IR treatment is irreversible damage to salivary gland in the IR field. While the exact mechanism of salivary gland damage remains enigmatic, fluid secreting acinar cells are lost, and saliva output is dramatically reduced. Previously we have reported that heat shock protein 25 (HSP25) induced radioresistance in vitro. HSP25 interferes negatively with apoptosis through several pathways which involve its direct interaction with cytochrome c, protein kinase c delta or Akt. And localized gene transfer to salivary glands has great potential for the treatment of salivary gland. Herein, we investigated whether HSP25 can use as radio protective molecules for radiation-induced salivary gland damage in vivo

  6. Radiation induced DNA double-strand breaks in radiology

    International Nuclear Information System (INIS)

    Shortly after the discovery of X-rays, their damaging effect on biological tissues was observed. The determination of radiation exposure in diagnostic and interventional radiology is usually based on physical measurements or mathematical algorithms with standardized dose simulations. γ-H2AX immunofluorescence microscopy is a reliable and sensitive method for the quantification of radiation induced DNA double-strand breaks (DSB) in blood lymphocytes. The detectable amount of these DNA damages correlates well with the dose received. However, the biological radiation damage depends not only on dose but also on other individual factors like radiation sensitivity and DNA repair capacity. Iodinated contrast agents can enhance the x-ray induced DNA damage level. After their induction DSB are quickly repaired. A protective effect of antioxidants has been postulated in experimental studies. This review explains the principle of the γ-H2AX technique and provides an overview on studies evaluating DSB in radiologic examinations.

  7. Radiation-induced conductivity in poly(phenylene vinylene) derivatives

    International Nuclear Information System (INIS)

    Using the pulse-radiolysis time-resolved microwave conductivity technique the mobility and decay kinetics of radiation-induced charge carriers is studied in a series of poly(2,5-dialkoxy-phenylene vinylene) derivatives. The lower limit to the sum of the mobilities of the positive and negative charge carriers, Σμmin, depends strongly on the alkoxy functionalization and ranges from 1.2 x 10-7 to 1.4 x 10-6 m2/V x s at room temperature. Σμmin increases with the degree of order in the material. The after-pulse conductivity decay kinetics are disperse and are controlled by a combination of charge recombination and trapping. (author)

  8. Radiatively Induced Breaking of Conformal Symmetry in a Superpotential

    CERN Document Server

    Arbuzov, A B

    2015-01-01

    Radiatively induced symmetry breaking is considered for a toy model with one scalar and one fermion field unified in a superfield. It is shown that the classical quartic self-interaction of the superfield possesses a quantum infrared singularity. Application of the Coleman-Weinberg mechanism for effective potential leads to the appearance of condensates and masses for both scalar and fermion components. That induces a spontaneous breaking of the initial classical symmetries: the supersymmetry and the conformal one. The energy scales for the scalar and fermion condensates appear to be of the same order, while the renormalization scale is many orders of magnitude higher. A possibility to relate the considered toy model to conformal symmetry breaking in the Standard Model is discussed.

  9. Radiation-induced spindle cell sarcoma: A rare case report

    Directory of Open Access Journals (Sweden)

    Khan Mubeen

    2009-01-01

    Full Text Available Ionizing radiation has been known to induce malignant transformation in human beings. Radiation-induced sarcomas are a late sequel of radiation therapy. Most sarcomas have been reported to occur after exposure to a radiation dose of 55 Gray (Gy and above, with a dose ranging from 16 to 112 Gys. Spindle cell sarcomas, arising after radiotherapy given to treat the carcinoma of head and neck region is a very uncommon sequel. This is a rare case report of spindle cell sarcoma of left maxilla, in a 24-year-old male, occurring as a late complication of radiotherapy with Cobalt-60 given for the treatment of retinoblastoma of the left eye 21 years back.

  10. The radiation-induced grafting of vinylpyridines to cellulose

    International Nuclear Information System (INIS)

    A wide range of solvents have been examined for the radiation-induced grafting to cellulose of 2- and 4-vinylpyridines and 2-methyl-5-vinylpyridine by the mutual irradiation technique. The presence of a functional group containing a nitrogen and/or oxygen atom in the solvent is important for high grafting efficiency. The two most favourable groups are NH2 and OH, the former being the more effective. Inclusion of both groups in suitable positions in the one molecule, the aminoalkanols in particular (e.g. 2-aminoethanol), leads to maximum effect in grafting. Heterocyclic solvents such as pyridine and 3-picoline are also useful. Other variables affecting grafting and studied in these experiments were the effect of pK, as well as swelling, wetting and dielectric strength of solvents. The effect of surface area of cellulose on copolymerization was also examined. A novel ionic mechanism for the grafting reaction involving association between solvent and monomer is proposed. (Author)

  11. Modification of microcystalline cellulose by gamma radiation-induced grafting

    International Nuclear Information System (INIS)

    Modified crystalline cellulose (MCC) was prepared through gamma radiation-induced graft polymerization of glycidyl methacrylate (GMA). Simultaneous grafting was employed wherein MCC with GMA in methanol was irradiated with gamma radiation in nitrogen atmosphere. The effects of different experimental factors such as monomer concentration, type of solvent and absorbed dose on the degree of grafting, Dg, were studied. The amount of grafted GMA, expressed as Dg, was determined gravimetrically. Information from grafted samples subjected to Fourier transformed infrared spectroscopy (FTIR) in attenuated total reflectance (ATR) mode showed peaks corresponding to GMA which indicates successful grafting. The X-ray diffraction (XRD) analysis revealed that the crystalline region of MCC was not adversely affected after grafting with GMA. The thermogravimetric analysis (TGA) data showed that the decomposition of grafted MCC occurred at higher temperature compared to the base MCC polymer. (author)

  12. Factors that modify risks of radiation-induced cancer

    International Nuclear Information System (INIS)

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

  13. Probabilistic methodology for estimating radiation-induced cancer risk

    International Nuclear Information System (INIS)

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

  14. Kinetic features of radiation-induced electric conductivity in polymers

    International Nuclear Information System (INIS)

    Dependence of radiation-induced electric conductivity (EC) of certain polymers on the time of irradiation by accelerated electrons (75 keV in the range of dose rate D = 20-500 Gy/s) with varying irradiation temperature, dose rate and electric field intensity has been studied. Existence of three stages of EC increase has been revealed in all the polymers studied: 'instant' (time of increment t << 1 s), 'fast' (t = 1-10 s) and 'decelerated' (t = 10-1000 s). It is shown that kinetic regularities of polymer EC can not be coordinated in the framework of the model of multiple capture of charges. The conclusion is made on determining role of molecular mobility in transfer of charge carriers generated by ionizing radiation. 12 refs., 4 figs., 1 tab

  15. X-radiation-induced chromosome breakage in retinoblastoma lymphocytes

    International Nuclear Information System (INIS)

    The authors have examined the spontaneous and X-radiation-induced chromosomal damage in normal humans and in patients with retinoblastoma using the BudR-Giemsa technique in lymphocytes cultured for 48 h. 9 sporadic unilateral non-hereditary cases, 11 hereditary cases and 20 healthy individuals were studied simultaneously. No difference in the spontaneous frequency of chromatid and chromosome aberrations was observed between patients and controls. The results suggest that: (a) There is no relationship between spontaneous chromosome fragility and retinoblastoma. (b) Sporadic unilateral non-hereditary retinoblastoma has normal chromosome sensitivity to X-irradiation. (c) Some hereditary cases of retinoblastoma are sensitive to X-rays while others behave like normals. A mutation or a submicroscopic deletion at a DNA repair locus which is independent of the retinoblastoma gene may cause this radiosensitivity. (Auth.)

  16. A preliminary report on radiation-induced stimulation in rice

    International Nuclear Information System (INIS)

    Radiation-induced stimulation is an oft-reported but controversial phenomenon. Rice var D-6-2-2 was tested for stimulation of yield using 60Co gamma-rays (500R - 100kR) and X-rays (100R - 5kR). Moisture variation was also used as a sub-treatment. Stimulation of both grain and straw yield was observed with both types of radiation but at different doses and varying with moisture conditions. Greenhouse experiments on seedling growth and laboratory experiments on germination rate, water uptake and other physiological processes, show that stimulation exhibited at a very early stage of growth, can be correlated to final yield. It might thus be possible to do primary screening for yield response by seedling performance of the varieties. (author)

  17. Chromosomal anomalies in radiation-induced fibrosis in the pig

    International Nuclear Information System (INIS)

    R-banded karyotypes were established on fibroblasts from fibrotic tissues derived from experimental fibrosis induced in pigs, either surgically or by 64 Gy of γ-rays from iridium-192. No chromosome aberrations were observed in the surgical fibrosis. In radiation-induced fibrosis, the high frequency of abnormal karyotypes and frequent complexity of the chromosomal rearrangements suggest that the fibroblasts originated either from the 64-Gy area, or from the penumbra, but certainly not from non-irradiated areas. At early passages in vitro, almost all karyotypes were different, demonstrating a multiclonal origin of fibrotic tissue. At late passages (above 24), the situation was quite different, with the persistence of one or two clones only, demonstrating a strong selective pressure occurring in vitro. (author). 23 refs., 2 figs., 2 tabs

  18. Radiation induced crystallinity damage in poly(L-lactic acid)

    International Nuclear Information System (INIS)

    The radiation-induced crystallinity damage in poly(L-lactic acid) (PLLA) in the presence of air and in vacuum, is studied. From the heat of fusion enthalpy values of gamma irradiated samples, some changes on the thermal properties were determined. To identify these changes, first the glass transition temperature (Tg) of L-lactic acid polymers irradiated to various doses in air and vacuum have been investigated and it is found that it is independent of irradiation atmosphere and dose. The fraction of damaged units of PLLA per unit of absorbed energy has been measured. For this purpose, SAXS and differential scanning calorimetry methods were used, and the radiation yield of number of damaged units (G(-u)) is found to be 0.74 and 0.58 for PLLA samples irradiated in vacuum and air, respectively

  19. Radiation induced crystallinity damage in poly(L-lactic acid)

    CERN Document Server

    Kantoglu, O

    2002-01-01

    The radiation-induced crystallinity damage in poly(L-lactic acid) (PLLA) in the presence of air and in vacuum, is studied. From the heat of fusion enthalpy values of gamma irradiated samples, some changes on the thermal properties were determined. To identify these changes, first the glass transition temperature (T sub g) of L-lactic acid polymers irradiated to various doses in air and vacuum have been investigated and it is found that it is independent of irradiation atmosphere and dose. The fraction of damaged units of PLLA per unit of absorbed energy has been measured. For this purpose, SAXS and differential scanning calorimetry methods were used, and the radiation yield of number of damaged units (G(-u)) is found to be 0.74 and 0.58 for PLLA samples irradiated in vacuum and air, respectively.

  20. Proton spectroscopy of radiation-induced injury to the brain

    International Nuclear Information System (INIS)

    This paper reports on the role of hydrogen MR spectroscopy (HMRS) in differentiating radiation-injured brain from normal brain and neoplasm, the authors performed HMRS on five cat brains with iatrogenically produced radiation injury. Reductions in N-acetyl aspartate (NAA/choline, and NAA/creatine-phosphocreatine (CR)) resonances were demonstrated in voxels from the five irradiated hemispheres compared with normal hemispheres (P < .01). NAA/CR ratios below 1.21 were always associated with radiation injury; ratios above 1.30 demarcated normal hemispheres. Large unassigned amino acid resonances from 2.0 to 2.5 ppm were also present. Results of autopsy examination confirmed radiation-induced white matter injury. Using NAA/CR ratios, one can separate normal brain from radiation-injured brain. Differentiating residual tumor from radiation-injured and normal brain may be possible with HMRS

  1. Radiation-induced radicals in hydrated magnesium sulfate

    International Nuclear Information System (INIS)

    Radiation-induced free radicals in hydrated magnesium sulfate, which are thought to be present on the surface of Europa, one of the Jovian moons, have been studied by electron spin resonance (ESR). ESR signals of both atomic hydrogen (H·) at g = 2.0023 and sulfite radical (SO3−·) at g = 2.0029 are observed in epsomite (MgSO4·7H2O) and in quenched samples of magnesium sulfate solutions, after gamma-ray irradiation at 77 K. Atomic hydrogen disappears at temperatures above 90 K. The sulfite radical starts to decay above 190 K in the quenched sample of 10% magnesium sulfate solution, whereas in epsomite, it is stable even at 260 K. The sulfite radical accumulates at low ambient temperatures, and is a promising candidate for estimating the age of hydrated magnesium sulfate, especially in extraterrestrial environments.

  2. Promotion of radiation-induced cationic polymerization by onium salts

    International Nuclear Information System (INIS)

    The radiation-induced cationic polymerization of styrene derivatives was studied in the presence of diphenyliodonium and triphenylsulfonium hexafluorophosphates in dichloromethane. A remarkable promotion of the polymerization was observed in the presence of the salts. The pulse radiolysis study revealed that the promotion of the polymerization is due to the ion-pair formation between the initiating cations and the nonnucleophilic complex metal halide anions of the salts resulting in the stabilization of the cations toward neutralization. An additional effect observed in the case of diphenyliodonium salt is the oxidation of free radical species to the cations responsible for the polymerization. An increase in molecular weight at low temperature suggested that the propagating cations are also paired with the counterions derived from the salts. (author)

  3. Radiation-induced mucositis pain in mesopharyngeal and hypopharyngeal cancer

    International Nuclear Information System (INIS)

    Radiation therapy in head and neck malignancy often triggers painful mucositis poorly controlled by nonsteroidal antiinflammatory drugs (NSAIDs). To better understand how radiation-induced pain develops over time, we studied numerical rating scale (NRS 0-5) pain scores in 27 subjects undergoing 60-72 Gy radiation therapy for newly diagnosed cancer- 13 with mesopharynx and 14 with hypopharynx. Mucositis severity was evaluated using Common Terminology Criteria for Adverse Events version 3.0 (CTCAE v3.0) based on mucositis pain, analgesic administration, and oral feedings of our subjects, with 8 mesopharyngeal and 10 with hypopharyngeal cancer had been pain-free before radiation therapy. The mucositis and pain course was severer in mesopharyngeal than in hypopharyngeal cancer. NSAIDs and opioid use was similar in both cancer types, which also required tube feeding in 7 subjects (38.9%). (author)

  4. Invertase immobilization onto radiation-induced graft copolymerized polyethylene pellets

    International Nuclear Information System (INIS)

    The graft polymer poly(ethylene-g-acrylic acid) (LDPE-g-AA) was prepared by radiation-induced graft copolymerization of acrylic acid onto low density polyethylene (LDPE) pellets, and characterized by infrared photoacoustic spectroscopy and scanning electron microscopy (SEM). The presence of the grafted poly(acrylic acid) (PAA) was established. Invertase was immobilized onto the graft polymer and the thermodynamic parameters of the souble and immobilized enzyme were determined. The Michaelis constant, Km, and the maximum reaction velocity, Vmax, were determined for the free and the immobilized invertase. The Michaelis constant, Km was larger for the immobilized invertase than for the free enzyme, whereas Vmax, was smaller for the immobilized invertase. The thermal stability of the immobilized invertase was higher than that of the free enzyme. (Author)

  5. Reducing Xerostomia After Chemo-IMRT for Head-and-Neck Cancer: Beyond Sparing the Parotid Glands

    Energy Technology Data Exchange (ETDEWEB)

    Little, Michael [Department of Radiation Oncology, University of Michigan, Ann Arbor, MI (United States); Schipper, Matthew [Department of Radiation Oncology, University of Michigan, Ann Arbor, MI (United States); Cancer Center Biostatistics Core, University of Michigan, Ann Arbor, MI (United States); Feng, Felix Y.; Vineberg, Karen [Department of Radiation Oncology, University of Michigan, Ann Arbor, MI (United States); Cornwall, Craig; Murdoch-Kinch, Carol-Anne [Hospital Dentistry, University of Michigan, Ann Arbor, MI (United States); Eisbruch, Avraham, E-mail: eisbruch@umich.edu [Department of Radiation Oncology, University of Michigan, Ann Arbor, MI (United States)

    2012-07-01

    Purpose: To assess whether, in addition to sparing the parotid glands (PGs), xerostomia after chemotherapy plus intensity-modulated radiotherapy (chemo-IMRT) for head-and-neck cancer is affected by reducing the dose to the other salivary glands. Patients and Methods: In a prospective study, 78 patients with Stage III-IV oropharynx/nasopharynx cancer underwent chemo-IMRT, with the aim of sparing the parts of the bilateral PGs, oral cavity (OC) containing the minor salivary glands, and contralateral submandibular gland (SMG) outside the target (when contralateral level I was not a target). Before therapy and periodically for 24 months, validated patient-reported xerostomia questionnaire (XQ) scores and observer-graded xerostomia scores were recorded. Also, the stimulated and unstimulated saliva was measured selectively from each of the PGs and SMGs. The mean OC doses served as surrogates of minor salivary gland dysfunction. Regression models assessed the XQ and observer-graded xerostomia predictors. Results: Statistically significant predictors of the XQ score on univariate analysis included the OC, PG, and SMG mean doses and the baseline XQ score, time since RT, and both stimulated and unstimulated PG saliva flow rates. Similar factors were statistically significant predictors of observer-graded xerostomia. The OC, PG, and SMG mean doses were moderately intercorrelated (r = 0.47-0.55). On multivariate analyses, after adjusting for the PG and SMG doses, the OC mean dose (p < .0001), interval from RT (p < .0001), and stimulated PG saliva (p < .0025) were significant predictors of the XQ scores and the OC mean dose and time for observer-graded xerostomia. Although scatter plots showed no thresholds, an OC mean dose of <40 Gy and contralateral SMG mean dose of <50 Gy were each associated with low patient-reported and observer-rated xerostomia at almost all post-therapy points. Conclusion: The PG, SMG, and OC mean doses were significant predictors of both patient

  6. Reducing Xerostomia After Chemo-IMRT for Head-and-Neck Cancer: Beyond Sparing the Parotid Glands

    International Nuclear Information System (INIS)

    Purpose: To assess whether, in addition to sparing the parotid glands (PGs), xerostomia after chemotherapy plus intensity-modulated radiotherapy (chemo-IMRT) for head-and-neck cancer is affected by reducing the dose to the other salivary glands. Patients and Methods: In a prospective study, 78 patients with Stage III-IV oropharynx/nasopharynx cancer underwent chemo-IMRT, with the aim of sparing the parts of the bilateral PGs, oral cavity (OC) containing the minor salivary glands, and contralateral submandibular gland (SMG) outside the target (when contralateral level I was not a target). Before therapy and periodically for 24 months, validated patient-reported xerostomia questionnaire (XQ) scores and observer-graded xerostomia scores were recorded. Also, the stimulated and unstimulated saliva was measured selectively from each of the PGs and SMGs. The mean OC doses served as surrogates of minor salivary gland dysfunction. Regression models assessed the XQ and observer-graded xerostomia predictors. Results: Statistically significant predictors of the XQ score on univariate analysis included the OC, PG, and SMG mean doses and the baseline XQ score, time since RT, and both stimulated and unstimulated PG saliva flow rates. Similar factors were statistically significant predictors of observer-graded xerostomia. The OC, PG, and SMG mean doses were moderately intercorrelated (r = 0.47–0.55). On multivariate analyses, after adjusting for the PG and SMG doses, the OC mean dose (p < .0001), interval from RT (p < .0001), and stimulated PG saliva (p < .0025) were significant predictors of the XQ scores and the OC mean dose and time for observer-graded xerostomia. Although scatter plots showed no thresholds, an OC mean dose of <40 Gy and contralateral SMG mean dose of <50 Gy were each associated with low patient-reported and observer-rated xerostomia at almost all post-therapy points. Conclusion: The PG, SMG, and OC mean doses were significant predictors of both patient

  7. Derivation of dose-response parameters for xerostomia in head and neck tumour patients treated with radiation therapy

    OpenAIRE

    Xavier, Cláudia de Melo Rocha Peixoto

    2014-01-01

    Objetivo: Derivação de parâmetros dose-resposta para efeitos secundário da radioterapia, xerostomia, em doentes com tumores de cabeça e pescoço tratados no IPOCFG. Métodos e Materiais: Um total de 302 pacientes com tumores de cabeça e pescoço, tratados com Radioterapia de Intensidade Modulada (IMRT), foram incluídos neste estudo. O efeito secundário estudado foi xerostomia aguda e tardia, avaliadas segundo as recomendações do Radiation Therapy Oncology Group e da European ...

  8. Radiation-induced crosslinking and grafting reactions in polyethylene

    International Nuclear Information System (INIS)

    This dissertation is concerned with three aspects of the crosslinking and grafting reactions induced by ionizing radiation on polyethylenes. One is the effect of trace inert fillers on the radiation-induced crosslinking of polyethylene. Experiments were performed with silica filled samples of low-density polyethylene subjected to 5 and 10 Mrad doses of gammas and electrons. Contrary to Goriyendo's results the insoluble fraction was found to be independent of SiO2 concentrations up to 0.5% by volume of both a finely divided and coarse filler. Another unexplained phenomenon is the ability of acid to enhance the radiation-induced grafting of styrene to polyethylene. Experiments were performed using polyethylene films immersed in styrene-methanol solutions both with and without acid and oxygen. The results show the gamma-induced grafting rate is enhanced by the presence of acid even in O2-free systems, despite the fact that the acid does not permeate the film. To better understand the crystalline region of polyethylene, ESR measurements at low power levels were made on sngle crystals of n-eicosane (n-C20H42) irradiated with gammas at 770K. The relative yields and the migration and decay mechanisms of the radicals suggest that the fracture of C-H bonds in irradiated eicosane favors the yield of the interior secondary alkyl radical far more than is to be expected from a radom fracture pattern. The results also demonstrate that the intramolecular migration of the alkyl radical site is more rapid than intermolcular migration. An ionic mechanism is proposed for the production of the alkyl free radicals in irradiated polyethylene and all other solid linear alkanes. The non-random fracture pattern of the C-H bonds in alkanes is explained in terms of random ionization and positive hole migration to the energetically favored interior position, followed by the ionic processes of the Weiss mechanism

  9. Radiation-induced thyroid cancer after radiotherapy for childhood cancer

    International Nuclear Information System (INIS)

    Full text of the publication follows: The thyroid gland in children is among the most sensitive organs to the carcinogenic effects of ionizing radiation, and very young children are at especially high risk. Due to extreme sensitivity of the thyroid gland in children, there is a risk of radiation - induced thyroid cancer even when the thyroid gland is outside the irradiated field. Increased incidence of thyroid cancer has been noted following radiotherapy not only for childhood Hodgkin disease (majority of observed patients), but also for non-Hodgkin lymphoma, neuroblastoma, Wilms tumor, acute lymphocytic leukemia and tumors of the central nervous system also. Radiation-induced tumors begin to appear 5-10 years after irradiation and excess risk persists for decades, perhaps for the remainder of life. The incidence of thyroid cancer is two- to threefold higher among females than males. Most of the thyroid cancers that occur in association with irradiation are of the papillary type, for which the cure rate is high if tumors are detected early. Our Department in co-operation with Department of Children Hematology and Oncology Charles University Second Faculty of Medicine and Faculty Hospital Motol monitors patients after therapy for cancer in childhood for the long term period. The monitoring is focused on detection of thyroid disorders that occur as last consequences of oncology therapy, especially early detection of nodular changes in thyroid gland and thyroid carcinogenesis. The survey presents two patients observed in our department that were diagnosed with the papillary thyroid carcinoma which occurred 15 and more years after radiotherapy for childhood cancer. After total thyroidectomy they underwent therapy with radioiodine. After radiotherapy it is necessary to pursue a long-term following and assure interdisciplinary co-operation which enables early detection of last consequences of radiotherapy, especially the most serious ones as secondary carcinogenesis

  10. Defense mechanisms against radiation induced teratogenic damage in mice

    International Nuclear Information System (INIS)

    Experimental studies with mice have established that fetuses at midgestational stage are highly susceptible to malformation at high, but not low, doses of radiation. When DNA damage is produced by a small amount of radiation, it is efficiently eliminated by DNA repair. However, DNA repair is not perfect. There must be defense mechanisms other than DNA repair. In order to elucidate the essential role of p53 gene in apoptotic tissue repair, we compared the incidence of radiation-induced malformations and deaths (deaths after day 10) in wild-type p53 (+/+) mice and null p53 (-/-) mice. For p53 (+/+) mice, an X-ray dose of 2 Gy given at a high dose-rate (450 mGy/min) to fetuses at 9.5 days of gestation was highly lethal and considerably teratogenic whereas it was only slightly lethal but highly teratogenic for p53 (-/-) fetuses. This reciprocal relationship of radiosensitivity to malformations and deaths supports the notion that fetal tissues have a p53 -dependent idguardianln of the tissue that aborts cells bearing radiation-induced teratogenic DNA damage. When an equal dose of 2 Gy given at a 400-fold lower dose-rate (1.2 mGy/min), this dose became not teratogenic for p53 (+/+) fetuses exhibiting p53 -dependent apoptosis, whereas this dose remained teratogenic for p53 (-/-) fetuses unable to carry out apoptosis. Furthermore, when the dose was divided into two equal dose fractions (1+1 Gy) at high dose rate, separated by 24 hours, the incidences of malformations were equal with control level for p53 (+/+), but higher for p53 (-/-) mice. Hence, complete elimination of teratogenic damage from irradiated tissues requires a concerted cooperation of two mechanisms; proficient DNA repair and p53-dependent apoptotic tissue repair

  11. Radiation induced corrosion of copper for spent nuclear fuel storage

    International Nuclear Information System (INIS)

    The long term safety of repositories for radioactive waste is one of the main concerns for countries utilizing nuclear power. The integrity of engineered and natural barriers in such repositories must be carefully evaluated in order to minimize the release of radionuclides to the biosphere. One of the most developed concepts of long term storage of spent nuclear fuel is the Swedish KBS-3 method. According to this method, the spent fuel will be sealed inside copper canisters surrounded by bentonite clay and placed 500 m down in stable bedrock. Despite the importance of the process of radiation induced corrosion of copper, relatively few studies have been reported. In this work the effect of the total gamma dose on radiation induced corrosion of copper in anoxic pure water has been studied experimentally. Copper samples submerged in water were exposed to a series of total doses using three different dose rates. Unirradiated samples were used as reference samples throughout. The copper surfaces were examined qualitatively using IRAS and XPS and quantitatively using cathodic reduction. The concentration of copper in solution after irradiation was measured using ICP-AES. The influence of aqueous radiation chemistry on the corrosion process was evaluated based on numerical simulations. The experiments show that the dissolution as well as the oxide layer thickness increase upon radiation. Interestingly, the evaluation using numerical simulations indicates that aqueous radiation chemistry is not the only process driving the corrosion of copper in these systems. - Highlights: • Copper cubes were exposed to gamma radiation in anoxic pure water. • The dissolution of copper increases with increasing absorbed total dose. • The oxide layer formed consists mainly of cuprite. • Numerical simulations of the irradiation experiments were performed. • There is a large discrepancy between numerical simulations and experimental results

  12. [Radiation-induced cancers: state of the art in 1997].

    Science.gov (United States)

    Cosset, J M

    1997-01-01

    Scientists now have available a large amount of data dealing with radiation-induced neoplasms. These data went back to anecdotal observations which were made in the very first years of utilization of X-rays and radioactive elements. In fact, it is essentially the strict follow-up of the Japanese populations irradiated by the Hiroshima and Nagasaki bombing which allowed a more precise evaluation of the carcinogenicity of ionizing radiations. Further refinements came from therapeutical irradiations: it is now possible to study large cohorts of patients given well-known doses in well-defined volumes and followed for more than 20 years. Last but not least, a significant increase in the incidence and mortality of thyroid cancer has been detected in children contaminated by iodine radioisotopes after the Tchernobyl accident. Recently, some data suggested the emergence of "clusters" of leukemias close to some nuclear facilities, but this question remains highly polemical, both in France and in the UK. Other questions are still waiting for a precise answer; of course, the extrapolation of our available data to very low doses delivered at very low dose rates, but also the carcinogenic risk at high doses. For these "high" doses (about 30 to 70 Gy), a competition between mutagenesis and cell killing was expected, so that these dose levels were expected to be less carcinogenic than lower (a few sieverts) doses. Actually, recent data suggest that the carcinogenic risk goes on increasing up to relatively important doses. In addition, carcinogenic factors, such as tabacco, anticancer chemotherapy and individual susceptibility, are found more and more to be closely intricated with ionizing radiation in the genesis of a given cancer. Even if a number of questions are still pending, the already available data allow specialists, both in medicine and radioprotection, to edict strict rules which can be reasonably expected to have significantly reduced the risk of radiation-induced

  13. Radiation-induced brachial plexus neuropathy in breast cancer patients

    Energy Technology Data Exchange (ETDEWEB)

    Olsen, N.K.; Pfeiffer, P.; Mondrup, K.; Rose, C. (Odense Univ. Hospital (Denmark). Dept. of Neurology Odense Univ. Hospital (Denmark). Dept. of Clinical Neurophysiology Odense Univ. Hospital (Denmark). Dept. of Oncology R)

    1990-01-01

    The incidence and latency period of radiation-induced brachial plexopathy (RBP) were assessed in 79 breast cancer patients by a neurological follow-up examination at least 60 months (range 67-130 months) after the primary treatment. All patients were treated primarily with simple mastectomy, axillary nodal sampling and radiotherapy (RT). Postoperatively, pre- and postmenopausal patients were randomly allocated chemotherapy for antiestrogen treatment. All patients were recurrence-free at time of examination. Clinically, 35% (25-47%) of the patients had RBP; 19% (11-29%) had definite RBP, i.e. were physically disabled, and 16% (9-26%) had probable RBP. Fifty percent (31-69%) had affection of the entire plexus, 18% (7-35%) of the upper trunk only, and 4% (1-18%) of the lower trunk. In 28% (14-48%) of cases assessment of a definite level was not possible. RBP was more common after radiotherapy and chemotherapy (42%) than after radiotherapy alone (26%) but the difference was not statistically significant (p = 0.10). The incidence of definite RBP was significantly higher in the younger age group (p = 0.02). This could be due to more extensive axillary surgery but also to the fact that chemotherapy was given to most premenopausal patients. In most patients with RBP the symptoms began during or immediately after radiotherapy, and were thus without significant latency. Chemotherapy might enhance the radiation-induced effect on nerve tissue, thus diminishing the latency period. Lymphedema was present in 22% (14-32%), especially in the older patients, and not associated with the development of RBP. In conclusion, the damaging effect of RT on peripheral nerve tissue was documented. Since no successful treatment is available, restricted use of RT to the brachial plexus is warranted, especially when administered concomitantly with cytotoxic therapy. (orig.).

  14. Radiation-induced brachial plexus neuropathy in breast cancer patients

    International Nuclear Information System (INIS)

    The incidence and latency period of radiation-induced brachial plexopathy (RBP) were assessed in 79 breast cancer patients by a neurological follow-up examination at least 60 months (range 67-130 months) after the primary treatment. All patients were treated primarily with simple mastectomy, axillary nodal sampling and radiotherapy (RT). Postoperatively, pre- and postmenopausal patients were randomly allocated chemotherapy for antiestrogen treatment. All patients were recurrence-free at time of examination. Clinically, 35% (25-47%) of the patients had RBP; 19% (11-29%) had definite RBP, i.e. were physically disabled, and 16% (9-26%) had probable RBP. Fifty percent (31-69%) had affection of the entire plexus, 18% (7-35%) of the upper trunk only, and 4% (1-18%) of the lower trunk. In 28% (14-48%) of cases assessment of a definite level was not possible. RBP was more common after radiotherapy and chemotherapy (42%) than after radiotherapy alone (26%) but the difference was not statistically significant (p = 0.10). The incidence of definite RBP was significantly higher in the younger age group (p = 0.02). This could be due to more extensive axillary surgery but also to the fact that chemotherapy was given to most premenopausal patients. In most patients with RBP the symptoms began during or immediately after radiotherapy, and were thus without significant latency. Chemotherapy might enhance the radiation-induced effect on nerve tissue, thus diminishing the latency period. Lymphedema was present in 22% (14-32%), especially in the older patients, and not associated with the development of RBP. In conclusion, the damaging effect of RT on peripheral nerve tissue was documented. Since no successful treatment is available, restricted use of RT to the brachial plexus is warranted, especially when administered concomitantly with cytotoxic therapy. (orig.)

  15. Radiation-induced thyroid cancer after radiotherapy for childhood cancer

    Energy Technology Data Exchange (ETDEWEB)

    Jiravova, M. [Department of Nuclear Medicine and Endocrinology, Faculty Hospital Motol, Uk, Prague (Czech Republic)

    2012-07-01

    Full text of the publication follows: The thyroid gland in children is among the most sensitive organs to the carcinogenic effects of ionizing radiation, and very young children are at especially high risk. Due to extreme sensitivity of the thyroid gland in children, there is a risk of radiation - induced thyroid cancer even when the thyroid gland is outside the irradiated field. Increased incidence of thyroid cancer has been noted following radiotherapy not only for childhood Hodgkin disease (majority of observed patients), but also for non-Hodgkin lymphoma, neuroblastoma, Wilms tumor, acute lymphocytic leukemia and tumors of the central nervous system also. Radiation-induced tumors begin to appear 5-10 years after irradiation and excess risk persists for decades, perhaps for the remainder of life. The incidence of thyroid cancer is two- to threefold higher among females than males. Most of the thyroid cancers that occur in association with irradiation are of the papillary type, for which the cure rate is high if tumors are detected early. Our Department in co-operation with Department of Children Hematology and Oncology Charles University Second Faculty of Medicine and Faculty Hospital Motol monitors patients after therapy for cancer in childhood for the long term period. The monitoring is focused on detection of thyroid disorders that occur as last consequences of oncology therapy, especially early detection of nodular changes in thyroid gland and thyroid carcinogenesis. The survey presents two patients observed in our department that were diagnosed with the papillary thyroid carcinoma which occurred 15 and more years after radiotherapy for childhood cancer. After total thyroidectomy they underwent therapy with radioiodine. After radiotherapy it is necessary to pursue a long-term following and assure interdisciplinary co-operation which enables early detection of last consequences of radiotherapy, especially the most serious ones as secondary carcinogenesis

  16. Radiation-induced leukemia: Comparative studies in mouse and man

    Energy Technology Data Exchange (ETDEWEB)

    Haas, M.

    1991-01-01

    We now have a clear understanding of the mechanism by which radiation-induced (T-cell) leukemia occurs. In irradiated mice (radiation-induced thymic leukemia) and in man (acute lymphoblastic T-cell leukemia, T-ALL) the mechanism of leukemogenesis is surprisingly similar. Expressed in the most elementary terms, T-cell leukemia occurs when T-cell differentiation is inhibited by a mutation, and pre-T cells attempt but fail to differentiate in the thymus. Instead of leaving the thymus for the periphery as functional T-cells they continue to proliferate in the thymus. The proliferating pre- (pro-) T-cells constitute the (early) acute T-cell leukemia (A-TCL). This model for the mechanism of T-cell leukemogenesis accounts for all the properties of both murine and human A-TCL. Important support for the model has recently come from work by Ilan Kirsch and others, who have shown that mutations/deletions in the genes SCL (TAL), SIL, and LCK constitute primary events in the development of T-ALL, by inhibiting differentiation of thymic pre- (pro-) T-cells. This mechanism of T-cell leukemogenesis brings several specific questions into focus: How do early A-TCL cells progress to become potently tumorigenic and poorly treatable Is it feasible to genetically suppress early and/or progressed A-TCL cells What is the mechanism by which the differentiation-inhibited (leukemic) pre-T cells proliferate During the first grant year we have worked on aspects of all three questions.

  17. Radiation-induced cancers: a 1997 state of the art

    International Nuclear Information System (INIS)

    Scientists now have available a large amount of data dealing whit radiation-induced neoplasms. These data went back to anecdotal observations which were made in the very first years of utilization of X-rays and radioactive elements. In fact, it is essentially the strict follow-up of the Japanese populations irradiated by the Hiroshima and Nagasaki bombing which allowed a more precise evaluation of the carcinogenicity of ionizing radiations. Further refinements came from therapeutical irradiations: it is now possible to study large cohorts of patient given well-known doses in well defined volumes and followed for more than 20 years. Last but not least, a significant increase in the incidence and mortality of thyroid cancer has been detected in children contaminated by iodine radioisotopes after the Tchernobyl accident. Recently, some data suggested the emergence of 'clusters' of leukemias close to some nuclear facilities, but this question remains highly polemical, both in France and in the UK. Other questions are still waiting for a precise answer; of course, the extrapolation of our available data to very low does delivered at very low dose rates, but also the carcinogenic risk at high doses. For these 'high' doses (about 30 to 70 Gy), a competition between mutagenesis and cell killing was expected, so that these dose levels were expected to be less carcinogenic than lower (a few sieverts) doses. Actually, recent data suggest that the carcinogenic risk goes on increasing up to relatively important doses. In addition, carcinogenic factors, such as tobacco, anticancer chemotherapy and individual susceptibility, are found more and more to be closely intricated with ionizing radiation in the genesis of a given cancer. Even if a number of questions are still pending, the already available data allow specialists, both medicine and radioprotection, to edict strict rules which can be reasonable expected to have significantly reduced the risk of radiation-induced neoplasms

  18. Genomic alterations in radiation-induced murine acute myeloid leukemias

    International Nuclear Information System (INIS)

    High-dose radiation induces acute myeloid leukemia (AML) in C3H mice, most of which have a high frequent hemizygous deletion around the D2Mit15 marker on the interstitially deleted region of chromosome 2. This region involves PU.1 (Sfpi-1), which is a critical candidate gene for initiation of mouse leukemogenesis. To identify other genes contributing to leukemogenesis with PU.1, we analyzed chromosomal aberrations and changes of expression in 18 AML-related genes in 39 AMLs. Array CGH analysis revealed that 35 out of 39 AMLs had hemizygous deletions of chromosome 2, and recurrent aberrations on chromosomes 4, 6, 8, 10, 11, 12, 15, and 18. Expressions of 18 AML-related genes, within the altered chromosome regions detected by array CGH were analyzed by using RT-PCR and/or real-time PCR. Although Wnt5b, Wnt16, G-CSFR, M-CSFR, SCL/Tal-1 and GATA1 genes were down-regulated, the c-myc gene was, on the contrary, up-regulated. Expression levels of two genes, Rasgrp1 and Wt1, within the deleted region of chromosome 2 correlated with the loss of one of two alleles, although the expression of PU.1 showed an inverse correlation. In addition, the expression level of PU.1 appeared to be higher with a coincidental missense point mutation in DNA-binding domain of PU.1 in the remaining allele, suggesting a feedback transcription control on PU.1. Such an autoregulation might be relevant to the fact that PU.1 haploinsufficiency per se triggers radiation-induced AML. Together with the detection of chromosomal aberrations, these findings provide useful clues to identify cooperative genes that are responsible for molecular pathogenesis of AMLs induced by low-dose-rate radiation exposure. (author)

  19. Genetic analysis of radiation-induced mouse thymic lymphomas

    International Nuclear Information System (INIS)

    Mouse thymic lymphomas are one of the classic models of radiation-induced malignancies, and the model has been used for the study of genes involved in carcinogenesis. ras oncogenes are the first isolate which undergoes mutations in 10 to 30 % of lymphomas, and p16INK4a and p19ARF in the INK4a-ARF locus are also frequently inactivated. In our previous study, the inactivation of Ikaros, a key regurator of lymphoid system, was found in those lymphomas, and it was suggested that there are other responsible genes yet to be discovered. On the other hand, genetic predisposition to radiation-induced lymphoma often differs in different strains, and this reflects the presence of low penetrance genes that can modify the impact of a given mutation. Little study of such modifiers or susceptibility genes has been performed, either. Recent availability of databases on mouse genome information and the power of mouse genetic system underline usefulness of the lymphoma model in search for novel genes involved, which may provide clues to molecular mechanisms of development of the radiogenic lymphoma and also genes involved in human lymphomas and other malignancies. Accordingly, we have carried out positional cloning for the two different types of tumor-related genes. In this symposium, our current progress is presented that includes genetic mapping of susceptibility/ resistance loci on mouse chromosomes 4, 5 and 19, and also functional analysis of a novel tumor suppressor gene, Rit1/Bcl11b, that has been isolated from allelic loss (LOH) mapping and sequence analysis for γ -ray induced mouse thymic lymphomas

  20. Role of Oxidative Damage in Radiation-Induced Bone Loss

    Science.gov (United States)

    Schreurs, Ann-Sofie; Alwood, Joshua S.; Limoli, Charles L.; Globus, Ruth K.

    2014-01-01

    used an array of countermeasures (Antioxidant diets and injections) to prevent the radiation-induced bone loss, although these did not prevent bone loss, analysis is ongoing to determine if these countermeasure protected radiation-induced damage to other tissues.

  1. Radiation induces aerobic glycolysis through reactive oxygen species

    International Nuclear Information System (INIS)

    Background and purpose: Although radiation induced reoxygenation has been thought to increase radiosensitivity, we have shown that its associated oxidative stress can have radioprotective effects, including stabilization of the transcription factor hypoxia inducible factor 1 (HIF-1). HIF-1 is known to regulate many of the glycolytic enzymes, thereby promoting aerobic glycolysis, which is known to promote treatment resistance. Thus, we hypothesized that reoxygenation after radiation would increase glycolysis. We previously showed that blockade of oxidative stress using a superoxide dismutase (SOD) mimic during reoxygenation can downregulate HIF-1 activity. Here we tested whether concurrent use of this drug with radiotherapy would reduce the switch to a glycolytic phenotype. Materials and methods: 40 mice with skin fold window chambers implanted with 4T1 mammary carcinomas were randomized into (1) no treatment, (2) radiation alone, (3) SOD mimic alone, and (4) SOD mimic with concurrent radiation. All mice were imaged on the ninth day following tumor implantation (30 h following radiation treatment) following injection of a fluorescent glucose analog, 2-[N-(7-nitrobenz-2-oxa-1,3-diaxol-4-yl)amino]-2-deoxyglucose (2-NBDG). Hemoglobin saturation was measured by using hyperspectral imaging to quantify oxygenation state. Results: Mice treated with radiation showed significantly higher 2-NBDG fluorescence compared to controls (p = 0.007). Hemoglobin saturation analysis demonstrated reoxygenation following radiation, coinciding with the observed increase in glycolysis. The concurrent use of the SOD mimic with radiation demonstrated a significant reduction in 2-NBDG fluorescence compared to effects seen after radiation alone, while having no effect on reoxygenation. Conclusions: Radiation induces an increase in tumor glucose demand approximately 30 h following therapy during reoxygenation. The use of an SOD mimic can prevent the increase in aerobic glycolysis when used

  2. Evidence for Radiation-Induced Disseminated Intravascular Coagulation as a Major Cause of Radiation-Induced Death in Ferrets

    International Nuclear Information System (INIS)

    Purpose: The studies reported here were performed as part of a program in space radiation biology in which proton radiation like that present in solar particle events, as well as conventional gamma radiation, were being evaluated in terms of the ability to affect hemostasis. Methods and Materials: Ferrets were exposed to 0 to 2 Gy of whole-body proton or gamma radiation and monitored for 30 days. Blood was analyzed for blood cell counts, platelet clumping, thromboelastometry, and fibrin clot formation. Results: The lethal dose of radiation to 50% of the population (LD50) of the ferrets was established at ∼1.5 Gy, with 100% mortality at 2 Gy. Hypocoagulability was present as early as day 7 postirradiation, with animals unable to generate a stable clot and exhibiting signs of platelet aggregation, thrombocytopenia, and fibrin clots in blood vessels of organs. Platelet counts were at normal levels during the early time points postirradiation when coagulopathies were present and becoming progressively more severe; platelet counts were greatly reduced at the time of the white blood cell nadir of 13 days. Conclusions: Data presented here provide evidence that death at the LD50 in ferrets is most likely due to disseminated intravascular coagulation (DIC). These data question the current hypothesis that death at relatively low doses of radiation is due solely to the cell-killing effects of hematopoietic cells. The recognition that radiation-induced DIC is the most likely mechanism of death in ferrets raises the question of whether DIC is a contributing mechanism to radiation-induced death at relatively low doses in large mammals

  3. Evidence for Radiation-Induced Disseminated Intravascular Coagulation as a Major Cause of Radiation-Induced Death in Ferrets

    Energy Technology Data Exchange (ETDEWEB)

    Krigsfeld, Gabriel S.; Savage, Alexandria R.; Billings, Paul C.; Lin, Liyong; Kennedy, Ann R., E-mail: akennedy@mail.med.upenn.edu

    2014-03-15

    Purpose: The studies reported here were performed as part of a program in space radiation biology in which proton radiation like that present in solar particle events, as well as conventional gamma radiation, were being evaluated in terms of the ability to affect hemostasis. Methods and Materials: Ferrets were exposed to 0 to 2 Gy of whole-body proton or gamma radiation and monitored for 30 days. Blood was analyzed for blood cell counts, platelet clumping, thromboelastometry, and fibrin clot formation. Results: The lethal dose of radiation to 50% of the population (LD{sub 50}) of the ferrets was established at ∼1.5 Gy, with 100% mortality at 2 Gy. Hypocoagulability was present as early as day 7 postirradiation, with animals unable to generate a stable clot and exhibiting signs of platelet aggregation, thrombocytopenia, and fibrin clots in blood vessels of organs. Platelet counts were at normal levels during the early time points postirradiation when coagulopathies were present and becoming progressively more severe; platelet counts were greatly reduced at the time of the white blood cell nadir of 13 days. Conclusions: Data presented here provide evidence that death at the LD{sub 50} in ferrets is most likely due to disseminated intravascular coagulation (DIC). These data question the current hypothesis that death at relatively low doses of radiation is due solely to the cell-killing effects of hematopoietic cells. The recognition that radiation-induced DIC is the most likely mechanism of death in ferrets raises the question of whether DIC is a contributing mechanism to radiation-induced death at relatively low doses in large mammals.

  4. Does salivary gland scintigraphy predict response to pilocarpine in patients with post-radiotherapy xerostomia?

    International Nuclear Information System (INIS)

    This study was undertaken to determine whether standard salivary gland scintigraphy may be used for the objective assessment of salivary gland sialogogues, in particular oral pilocarpine, in the treatment of post-radiotherapy xerostomia. Nine patients, with xerostomia following radiotherapy to the head and neck region underwent salivary gland scintigraphy with technetium-99m pertechnetate (40 MBq) both before and following 1 month of oral pilocarpine (5 mg tds). For each scan, the percentage uptake in the first 14 min, the peak uptake, time to peak uptake and the percentage of activity excreted following lemon juice stimulation were calculated. The results were correlated with the subjective response as assessed by questionnaire and visual analogue scale. We found no correlation between subjective response and any of the four scan parameters analysed. We could not identify any parameter that predicted those patients who would respond to pilocarpine. In addition, only one parameter, the percentage of activity excreted following stimulation, correlated with previous dose of radiotherapy to the gland. In conclusion, in this study salivary gland scintigraphy did not appear to correlate with or predict response to oral pilocarpine. However, future studies might consider performing salivary gland scintigraphy prior to radiotherapy as well as at differing time points following the commencement of pilocarpine. (orig.)

  5. Does salivary gland scintigraphy predict response to pilocarpine in patients with post-radiotherapy xerostomia?

    Energy Technology Data Exchange (ETDEWEB)

    Cooper, R.A.; Cowan, R.A.; Slevin, N.J.; Allan, E.; Gupta, N.K. [Department of Clinical Oncology, Christie Hospital, Manchester (United Kingdom); Owens, S.E.; Jeans, S.P.; Roberts, J.K.; Hillel, P.G. [North Western Medical Physics, Christie Hospital, Manchester (United Kingdom); Collins, C.D. [Department of Radiology, Christie Hospital, Manchester (United Kingdom)

    1999-03-01

    This study was undertaken to determine whether standard salivary gland scintigraphy may be used for the objective assessment of salivary gland sialogogues, in particular oral pilocarpine, in the treatment of post-radiotherapy xerostomia. Nine patients, with xerostomia following radiotherapy to the head and neck region underwent salivary gland scintigraphy with technetium-99m pertechnetate (40 MBq) both before and following 1 month of oral pilocarpine (5 mg tds). For each scan, the percentage uptake in the first 14 min, the peak uptake, time to peak uptake and the percentage of activity excreted following lemon juice stimulation were calculated. The results were correlated with the subjective response as assessed by questionnaire and visual analogue scale. We found no correlation between subjective response and any of the four scan parameters analysed. We could not identify any parameter that predicted those patients who would respond to pilocarpine. In addition, only one parameter, the percentage of activity excreted following stimulation, correlated with previous dose of radiotherapy to the gland. In conclusion, in this study salivary gland scintigraphy did not appear to correlate with or predict response to oral pilocarpine. However, future studies might consider performing salivary gland scintigraphy prior to radiotherapy as well as at differing time points following the commencement of pilocarpine. (orig.) With 6 figs., 1 tab., 20 refs.

  6. Industrialization of radiation-induced emulsion polymerization - technological process and its advantages

    International Nuclear Information System (INIS)

    A technological process for industrialization of radiation induced emulsion polymerization was introduced briefly. A batch process rather than a continuous one was adopted in the industrial-scale production. The advantages of radiation induced emulsion polymerization were described in comparison with chemical initiated process. (author)

  7. Studies on radiation induced radicals in irradiated black pepper after long-term storage

    International Nuclear Information System (INIS)

    Using ESR the radiation induced radicals of black pepper after long-term storage were studied. Upon gamma ray irradiation, new signals were detected as twin peaks. It was revealed that these signals were very stable after the six month storage. We concluded that radiation induced new signals are very useful to know that the black pepper was irradiated or not. (author)

  8. Pentoxifylline and vitamin E combination for superficial radiation-induced fibrosis: A phase II clinical trial

    International Nuclear Information System (INIS)

    We treated 34 radiation-induced superficial fibrotic lesions with pentoxifylline and vitamin E for 3 months. Mean surface area of the lesions decreased from 112 to 65 cm2 after treatment (P2 (P<0.001). Pentoxifylline-vitamin E combination improved radiation-induced fibrosis

  9. Countermeasures for Space Radiation Induced Malignancies and Acute Biological Effects

    Science.gov (United States)

    Kennedy, Ann

    The hypothesis being evaluated in this research program is that control of radiation induced oxidative stress will reduce the risk of radiation induced adverse biological effects occurring as a result of exposure to the types of radiation encountered during space travel. As part of this grant work, we have evaluated the protective effects of several antioxidants and dietary supplements and observed that a mixture of antioxidants (AOX), containing L-selenomethionine, N-acetyl cysteine (NAC), ascorbic acid, vitamin E succinate, and alpha-lipoic acid, is highly effective at reducing space radiation induced oxidative stress in both in vivo and in vitro systems, space radiation induced cytotoxicity and malignant transformation in vitro [1-7]. In studies designed to determine whether the AOX formulation could affect radiation induced mortality [8], it was observed that the AOX dietary supplement increased the 30-day survival of ICR male mice following exposure to a potentially lethal dose (8 Gy) of X-rays when given prior to or after animal irradiation. Pretreatment of animals with antioxidants resulted in significantly higher total white blood cell and neutrophil counts in peripheral blood at 4 and 24 hours following exposure to doses of 1 Gy and 8 Gy. Antioxidant treatment also resulted in increased bone marrow cell counts following irradiation, and prevented peripheral lymphopenia following 1 Gy irradiation. Supplementation with antioxidants in irradiated animals resulted in several gene expression changes: the antioxidant treatment was associated with increased Bcl-2, and decreased Bax, caspase-9 and TGF-β1 mRNA expression in the bone marrow following irradiation. These results suggest that modulation of apoptosis may be mechanistically involved in hematopoietic system radioprotection by antioxidants. Maintenance of the antioxidant diet was associated with improved recovery of the bone marrow following sub-lethal or potentially lethal irradiation. Taken together

  10. Unilateral versus bilateral irradiation in squamous cell head and neck cancer in relation to patient-rated xerostomia and sticky saliva

    International Nuclear Information System (INIS)

    Background and purpose: To investigate the association between radiation technique with patient-rated moderate and severe xerostomia and sticky saliva. Materials and methods: One hundred and fifty patients treated with bilateral or unilateral irradiation for head and neck cancer were included. The salivary glands and the oral cavity were delineated on plannings-CT scans. Xerostomia and sticky saliva were assessed using the EORTC QLQ-H and N35 questionnaire at baseline and 6 and 12 months. Results: At 6 months a significant association between radiation technique and the mean parotid dose (MDparb) and xerostomia was observed (Odds ratio (OR)-technique: 2.55; p = 0.04 and OR-MDparb: 1.04; p = 0.009). Considering the individual salivary glands, only the mean dose in the contralateral parotid gland (MDparcl) is associated with xerostomia (OR: 1.04; p parb influence the risk of xerostomia in irradiated patients. Of all individual salivary glands, only MDparcl is of utmost importance for xerostomia. The shift in the P50 observed for xerostomia suggests that sparing of the contralateral parotid gland is compensated by hyperfunction of the contralateral parotid gland

  11. Influence of radiation induced defect clusters on silicon particle detectors

    International Nuclear Information System (INIS)

    The Large Hadron Collider (LHC) at the European Organization for Nuclear Research (CERN) addresses some of today's most fundamental questions of particle physics, like the existence of the Higgs boson and supersymmetry. Two large general-purpose experiments (ATLAS, CMS) are installed to detect the products of high energy protonproton and nucleon-nucleon collisions. Silicon detectors are largely employed in the innermost region, the tracking area of the experiments. The proven technology and large scale availability make them the favorite choice. Within the framework of the LHC upgrade to the high-luminosity LHC, the luminosity will be increased to L=1035 cm-2s-1. In particular the pixel sensors in the innermost layers of the silicon trackers will be exposed to an extremely intense radiation field of mainly hadronic particles with fluences of up to Φeq=1016 cm-2. The radiation induced bulk damage in silicon sensors will lead to a severe degradation of the performance during their operational time. This work focusses on the improvement of the radiation tolerance of silicon materials (Float Zone, Magnetic Czochralski, epitaxial silicon) based on the evaluation of radiation induced defects in the silicon lattice using the Deep Level Transient Spectroscopy and the Thermally Stimulated Current methods. It reveals the outstanding role of extended defects (clusters) on the degradation of sensor properties after hadron irradiation in contrast to previous works that treated effects as caused by point defects. It has been found that two cluster related defects are responsible for the main generation of leakage current, the E5 defects with a level in the band gap at EC-0.460 eV and E205a at EC-0.395 eV where EC is the energy of the edge of the conduction band. The E5 defect can be assigned to the tri-vacancy (V3) defect. Furthermore, isochronal annealing experiments have shown that the V3 defect exhibits a bistability, as does the leakage current. In oxygen rich material the

  12. Influence of radiation induced defect clusters on silicon particle detectors

    Energy Technology Data Exchange (ETDEWEB)

    Junkes, Alexandra

    2011-10-15

    The Large Hadron Collider (LHC) at the European Organization for Nuclear Research (CERN) addresses some of today's most fundamental questions of particle physics, like the existence of the Higgs boson and supersymmetry. Two large general-purpose experiments (ATLAS, CMS) are installed to detect the products of high energy protonproton and nucleon-nucleon collisions. Silicon detectors are largely employed in the innermost region, the tracking area of the experiments. The proven technology and large scale availability make them the favorite choice. Within the framework of the LHC upgrade to the high-luminosity LHC, the luminosity will be increased to L=10{sup 35} cm{sup -2}s{sup -1}. In particular the pixel sensors in the innermost layers of the silicon trackers will be exposed to an extremely intense radiation field of mainly hadronic particles with fluences of up to {phi}{sub eq}=10{sup 16} cm{sup -2}. The radiation induced bulk damage in silicon sensors will lead to a severe degradation of the performance during their operational time. This work focusses on the improvement of the radiation tolerance of silicon materials (Float Zone, Magnetic Czochralski, epitaxial silicon) based on the evaluation of radiation induced defects in the silicon lattice using the Deep Level Transient Spectroscopy and the Thermally Stimulated Current methods. It reveals the outstanding role of extended defects (clusters) on the degradation of sensor properties after hadron irradiation in contrast to previous works that treated effects as caused by point defects. It has been found that two cluster related defects are responsible for the main generation of leakage current, the E5 defects with a level in the band gap at E{sub C}-0.460 eV and E205a at E{sub C}-0.395 eV where E{sub C} is the energy of the edge of the conduction band. The E5 defect can be assigned to the tri-vacancy (V{sub 3}) defect. Furthermore, isochronal annealing experiments have shown that the V{sub 3} defect

  13. Reduced sulfation of muc5b is linked to xerostomia in patients with Sjögren syndrome

    NARCIS (Netherlands)

    C. Alliende; Y.-J. Kwon; M. Brito; C. Molina; S. Aguilera; P. Pérez; L. Leyton; A.F.G. Quest; U. Mandel; E. Veerman; M. Espinosa; H. Clausen; C. Leyton; R. Romo; S. González

    2008-01-01

    Objectives: MUC5B contains sulfated and sialylated oligosaccharides that sequester water required for moisturising the oral mucosa. Xerostomia, in patients with Sjögren syndrome, is generally associated with reduced quantities, rather than altered properties, of saliva. Here, we determined the amoun

  14. A systematic review of salivary gland hypofunction and xerostomia induced by cancer therapies: management strategies and economic impact

    DEFF Research Database (Denmark)

    Jensen, S.B.; Pedersen, A.M.L.; Vissink, A.;

    2010-01-01

    This systematic review aimed to assess the literature for management strategies and economic impact of salivary gland hypofunction and xerostomia induced by cancer therapies and to determine the quality of evidence-based management recommendations. The electronic databases of MEDLINE/PubMed and E...

  15. A systematic review of salivary gland hypofunction and xerostomia induced by cancer therapies : management strategies and economic impact

    NARCIS (Netherlands)

    Jensen, S. B.; Pedersen, A. M. L.; Vissink, A.; Andersen, E.; Brown, C. G.; Davies, A. N.; Dutilh, J.; Fulton, J. S.; Jankovic, L.; Lopes, N. N. F.; Mello, A. L. S.; Muniz, L. V.; Murdoch-Kinch, C. A.; Nair, R. G.; Napenas, J. J.; Nogueira-Rodrigues, A.; Saunders, D.; Stirling, B.; von Bueltzingsloewen, I.; Weikel, D. S.; Spijkervet, F. K. L.; Brennan, M. T.; Elting, L.

    2010-01-01

    This systematic review aimed to assess the literature for management strategies and economic impact of salivary gland hypofunction and xerostomia induced by cancer therapies and to determine the quality of evidence-based management recommendations. The electronic databases of MEDLINE/PubMed and EMBA

  16. A systematic review of salivary gland hypofunction and xerostomia induced by cancer therapies: management strategies and economic impact

    DEFF Research Database (Denmark)

    Jensen, Siri Beier; Pedersen, Anne Marie Lynge; Vissink, Arjan;

    2010-01-01

    This systematic review aimed to assess the literature for management strategies and economic impact of salivary gland hypofunction and xerostomia induced by cancer therapies and to determine the quality of evidence-based management recommendations. The electronic databases of MEDLINE/PubMed and...

  17. Efficacy of a synthetic polymer saliva substitute in reducing oral complaints of patients suffering from irradiation-induced xerostomia

    NARCIS (Netherlands)

    Regelink, G; Vissink, A; Reintsema, H; Nauta, JM

    1998-01-01

    Objective: A saliva substitute based on polyglycerylmethacrylate, lactoperoxidase, and glucose oxidase (Oral Balance) has been developed. The aim of this study was to evaluate the effect of Oral Balance on the dryness-related oral complaints in patients suffering from irradiation-induced xerostomia.

  18. Association of Xerostomia and Assessment of Salivary Flow Using Modified Schirmer Test among Smokers and Healthy Individuals: A Preliminutesary Study

    OpenAIRE

    Dyasanoor, Sujatha; Saddu, Shweta Channavir

    2014-01-01

    Background and Objective: Several oral diseases such as dental caries, periodontitis and oral infections can be a major concern in patients suffering from mouth dryness. Whole mouth salivary flow is affected by many factors which may include habits like smoking. The aim of the present study was to investigate the incidence of xerostomia and hyposalivation among smokers.

  19. Translation and Validation of a Korean Version of the Xerostomia Inventory in Patients with Primary Sjögren's Syndrome.

    Science.gov (United States)

    Lee, Jennifer; Koh, Jung Hee; Kwok, Seung-Ki; Park, Sung-Hwan

    2016-05-01

    This study was conducted to generate and validate a cross-culturally adapted Korean version of the xerostomia inventory (XI), an 11-item questionnaire designed to measure the severity of xerostomia. The original English version of the XI was translated into Korean according to the guidelines for cross-cultural adaptation of health-related quality-of-life measures. Among a prospective cohort of primary Sjögren's syndrome (pSS) in Korea, 194 patients were analyzed. Internal consistency was evaluated by using Cronbach's alpha, and test-retest reliability was obtained by using an intraclass correlation coefficient (ICC) analysis. Construct validity was investigated by performing a correlation analysis between XI total score and salivary flow rate (SFR). Cronbach's alpha for internal consistency was 0.868, and the ICC for test-retest reliability ranged from 0.48 to 0.827, with a median value of 0.72. Moderate negative correlations between XI score and stimulated SFR, unstimulated SFR, and differential (stimulated minus unstimulated) SFR were observed (Spearman's rho, ρ = -0.515, -0.447, and -0.482, respectively; P xerostomia in the pSS patients. In conclusion, the Korean version of the XI is a reliable tool to estimate the severity of xerostomia in patients with pSS. PMID:27134493

  20. Early changes of parotid density and volume predict modifications at the end of therapy and intensity of acute xerostomia

    International Nuclear Information System (INIS)

    To quantitatively assess the predictive power of early variations of parotid gland volume and density on final changes at the end of therapy and, possibly, on acute xerostomia during IMRT for head-neck cancer. Data of 92 parotids (46 patients) were available. Kinetics of the changes during treatment were described by the daily rate of density (rΔρ) and volume (rΔvol) variation based on weekly diagnostic kVCT images. Correlation between early and final changes was investigated as well as the correlation with prospective toxicity data (CTCAEv3.0) collected weekly during treatment for 24/46 patients. A higher rΔρ was observed during the first compared to last week of treatment (-0,50 vs -0,05HU, p-value = 0.0001). Based on early variations, a good estimation of the final changes may be obtained (Δρ: AUC = 0.82, p = 0.0001; Δvol: AUC = 0.77, p = 0.0001). Both early rΔρ and rΔvol predict a higher ''mean'' acute xerostomia score (≥ median value, 1.57; p-value = 0.01). Median early density rate changes for patients with mean xerostomia score ≥ / 3/day for rΔρ and rΔvol respectively. Further studies are necessary to definitively assess the potential of early density/volume changes in identifying more sensitive patients at higher risk of experiencing xerostomia. (orig.)

  1. Phase III evaluation of sucralfate for radiation-induced esophagitis

    International Nuclear Information System (INIS)

    Purpose/Objective: To evaluate whether an oral sucralfate solution could prevent or alleviate symptoms of radiation-induced esophagitis in patients receiving thoracic radiation therapy. Materials and Methods: Patients considered for this trial must have been adults scheduled to receive thoracic radiation therapy to include the mediastinum to a dose of ≥ 5,000 cGy using 150 to 200 cGy per fraction or ≥ 4,000 cGy using ≥ 300 cGy per fraction. Contraindications to study participation included a known intolerance to sucralfate; previous radiation to the chest; planned use of sucralfate off study; pregnant or nursing women; cancers involving the mucosa of the esophagus; and/or an inability to take oral medications. Patients were stratified by their radiation therapy treatment plan, their age and their sex. Following stratification, they were randomized in a double blind manner to receive a sucralfate solution or an identical-appearing placebo solution. Esophagitis was measured by the treating physician, using the RTOG esophagitis toxicity grading criteria, at weekly intervals during the course of radiation therapy. In addition, patients completed short questionnaires weekly during the course of radiation therapy and for four weeks following completion of their radiation treatment program. Results: One hundred and two patients were randomized onto this study between August of 1993 and July of 1994. One patient was ineligible and four patients were cancelled prior to starting any study medication, leaving 97 total evaluable patients. All of the stratification factors were well balanced but there was a slightly higher incidence of current tobacco use in the placebo group. There was a differential drop out rate between the two arms. During the first two treatment weeks, only two of the placebo patients (4%) compared to 20 of the sucralfate patients (40%) dropped out of the study. After the second week, relatively equal drop out rates were seen with 9 sucralfate

  2. Safety consequences of the release of radiation induced stored energy

    International Nuclear Information System (INIS)

    Due to the disposal of HLW in a salt formation gamma energy will be deposited in the rock salt. Most of this energy will be converted into heat, whilst a small part will create defects in the salt crystals. Energy is stored in the damaged crystals. Due to uncertainties in the models and differences in the disposal concepts the estimated values for the stored energy range from 10 to 1000 J/g in the most heavily damaged crystals close to the waste containers. The amount of radiation damage decays exponentially with increasing distance from the containers and at distances larger than 0.2 m the stored energy can be neglected. Given the uncertainties in the model predictions and in the possible release mechanism an instantaneous release of stored energy cannot be excluded completely. Therefore the thermo-mechanical consequences of a postulated instantaneous release of an extremely high amount of radiation induced stored energy have been estimated. These estimations are based on the quasi-static solutions for line and point sources. To account for the dynamic effects and the occurrence of fractures an amplification factor has been derived from mining experience with explosives. A validation of this amplification factor has been given using post experimental observations of two nuclear explosions in a salt formation. For some typical disposal concepts in rock salt the extent of the fractured zone has been estimated. It appeared that the radial extent of the fractured zone is limited to 5 m. Given the much larger distance between the individual boreholes and the distance between the boreholes and the boundary of the salt formation (more than 100 m), the probability of a release of radiation induced stored energy creating a pathway for the nuclides from the containers to the groundwater, is extremely low. The radiological consequences of a groundwater intrusion scenario induced by this very unprobable pathway are bounded by the 'standard' groundwater intrusion

  3. Radiation-induced defects in clay minerals: A review

    International Nuclear Information System (INIS)

    Extensive information has been collected on radiation effects on clay minerals over the last 35 years, providing a wealth of information on environmental and geological processes. The fields of applications include the reconstruction of past radioelement migrations, the dating of clay minerals or the evolution of the physico-chemical properties under irradiation. The investigation of several clay minerals, namely kaolinite, dickite, montmorillonite, illite and sudoite, by Electron Paramagnetic Resonance Spectroscopy has shown the presence of defects produced by natural or artificial radiations. These defects consist mostly of electron holes located on oxygen atoms of the structure. The various radiation-induced defects are differentiated through their nature and their thermal stability. Most of them are associated with a π orbital on a Si–O bond. The most abundant defect in clay minerals is oriented perpendicular to the silicate layer. Thermal annealing indicates this defect in kaolinite (A-center) to be stable over geological periods at ambient temperature. Besides, electron or heavy ion irradiation easily leads to an amorphization in smectites, depending on the type of interlayer cation. The amorphization dose exhibits a bell-shaped variation as a function of temperature, with a decreasing part that indicates the influence of thermal dehydroxylation. Two main applications of the knowledge of radiation-induced defects in clay minerals are derived: (i) The use of defects as tracers of past radioactivity. In geological systems where the age of the clay can be constrained, ancient migrations of radioelements can be reconstructed in natural analogues of high level nuclear waste repositories. When the dose rate may be assumed constant over time, the paleodose is used to date clay populations, an approach applied to fault gouges or laterites of the Amazon basin. (ii) The influence of irradiation over physico-chemical properties of clay minerals. An environmental

  4. Radiation-induced grafting of TMPM onto polypropylene

    International Nuclear Information System (INIS)

    The gamma radiation-induced graft copolymerization of 2,2,6,6-tetramethyl-4-piperidinyl-methacrylate (TMPM), a very effective hindered amine light stabilizer (HALS), onto polypropylene was investigated by simultaneous- irradiation technique. The various synthesis conditions on the graft content was studied. It was found that benzene, CCl4 and petroleum ether are more effective than other solvents, the percent grafting reached 7.1% for benzene. The percent grafting is higher when graft copolymerization is carried out in argon atmosphere than those in air. For all the grafting copolymerization carried out in benzene and CCl4, percent grafting increase linearly from 1 to 5 Mrad and beyond 5 Mrad, a tendency to level off appeared. At a constant dose, the percent grafting was found to be higher at high dose rate until 228 rad/s. Percent grafting also increased continuously with increasing monomer concentration up to 2.85 mol/L, but significant increase in grafting was observed only up to 1.14 mol/L

  5. Radiation-Induced Notch Signaling in Breast Cancer Stem Cells

    Energy Technology Data Exchange (ETDEWEB)

    Lagadec, Chann [Department of Radiation Oncology, David Geffen School of Medicine at University of California, Los Angeles (UCLA), Los Angeles, California (United States); Vlashi, Erina [Department of Radiation Oncology, David Geffen School of Medicine at University of California, Los Angeles (UCLA), Los Angeles, California (United States); Jonsson Comprehensive Cancer Center at UCLA, Los Angeles, California (United States); Alhiyari, Yazeed; Phillips, Tiffany M.; Bochkur Dratver, Milana [Department of Radiation Oncology, David Geffen School of Medicine at University of California, Los Angeles (UCLA), Los Angeles, California (United States); Pajonk, Frank, E-mail: fpajonk@mednet.ucla.edu [Department of Radiation Oncology, David Geffen School of Medicine at University of California, Los Angeles (UCLA), Los Angeles, California (United States); Jonsson Comprehensive Cancer Center at UCLA, Los Angeles, California (United States)

    2013-11-01

    Purpose: To explore patterns of Notch receptor and ligand expression in response to radiation that could be crucial in defining optimal dosing schemes for γ-secretase inhibitors if combined with radiation. Methods and Materials: Using MCF-7 and T47D breast cancer cell lines, we used real-time reverse transcription–polymerase chain reaction to study the Notch pathway in response to radiation. Results: We show that Notch receptor and ligand expression during the first 48 hours after irradiation followed a complex radiation dose–dependent pattern and was most pronounced in mammospheres, enriched for breast cancer stem cells. Additionally, radiation activated the Notch pathway. Treatment with a γ-secretase inhibitor prevented radiation-induced Notch family gene expression and led to a significant reduction in the size of the breast cancer stem cell pool. Conclusions: Our results indicate that, if combined with radiation, γ-secretase inhibitors may prevent up-regulation of Notch receptor and ligand family members and thus reduce the number of surviving breast cancer stem cells.

  6. Radiation-Induced Notch Signaling in Breast Cancer Stem Cells

    International Nuclear Information System (INIS)

    Purpose: To explore patterns of Notch receptor and ligand expression in response to radiation that could be crucial in defining optimal dosing schemes for γ-secretase inhibitors if combined with radiation. Methods and Materials: Using MCF-7 and T47D breast cancer cell lines, we used real-time reverse transcription–polymerase chain reaction to study the Notch pathway in response to radiation. Results: We show that Notch receptor and ligand expression during the first 48 hours after irradiation followed a complex radiation dose–dependent pattern and was most pronounced in mammospheres, enriched for breast cancer stem cells. Additionally, radiation activated the Notch pathway. Treatment with a γ-secretase inhibitor prevented radiation-induced Notch family gene expression and led to a significant reduction in the size of the breast cancer stem cell pool. Conclusions: Our results indicate that, if combined with radiation, γ-secretase inhibitors may prevent up-regulation of Notch receptor and ligand family members and thus reduce the number of surviving breast cancer stem cells

  7. Radiation induced crosslinking of polystyrene effect of molecular weight

    International Nuclear Information System (INIS)

    Previous data on the number average and weight average molecular weights of irradiated polystyrene samples (initially of uniform molecular weight) have been analysed. The results confirm theoretical relationships based on the assumptions that cross-links are formed at random throughout the specimens, and in proportion to radiation dose. A small but consistent difference in G values for crosslinkings as between number and weight average measurements, is ascribed to a small degree of radiation-induced scission: G (crosslinked units) approximately 34G (scission). The three series of specimens studied also show significant differences in G values, depending on molecular weight. This is ascribed to competition between intermolecular and intramolecular links - both are produced by radiation, but only the former influence molecular weight. If the concentrations of monomer units about any unit are csub(i) (other units of the same chain) and csub(e) (units of other chains) then the observed data agree with: csub(i)/csub(e) approximately 0.64 x 10-4Msup(0.5) while G (total crosslinked units) = 9.4 x 10-2 and G (scission) approximately 2.7 x 10-3. (author)

  8. Contribution to the study of radiation induced bone tissue cancer

    International Nuclear Information System (INIS)

    In this work four original observations of more or less long-delayed cancers induced by ionizing radiations are compared with 34 other cases in the literature, after which an attempt is made to establish a general and prognostic synthesis of the results; the indications to emerge are as follows: - Ionizing radiation-induced cancers are very rare, especially when compared with the extensive therapeutic use made of X-rays; - The probability of radio-cancer formation, though no figures are given in the many papers consulted, seems nevertheless to be higher in cases of benign lesion irradiation; - Induced cancers have been observed after treatments with all types of radiation, whether or not the lesion is tumoral or cancerous, whatever the patient's age at the time of irradiations; - As a general rule these neoplasms appear after a variable latency period but usually from the 6th post-radiotherapy year onwards, with a greater frequency range between 6 and 12 years; - These induced cancers are generally epitheliomas or sarcomas, the latter being noticeably more predominant than in the case of spontaneous cancers. Leukoses may also be observed

  9. Radiation induced emulsion polymerization of 2-ethylhexyl acrylate

    International Nuclear Information System (INIS)

    The effects of radiation dose rate concentration of emulsifier and monomer content on reaction rate of radiation induced 2-ethylhexyl acrylate (EHA) emulsion polymerization have been studied. Nonionic surfactants, polyoxyethylene alkyl ether peregolo 0 with HLB about 15 and polyoxyethylene nonylphenolether (emulsifier OP) with HLB 15, are used as the emulsifiers in this work. It has been found that the dependence of RP on I (RP proportional to In) is changed with the index n from 0.29 for M/W = 2/8 (monomer/water in volume) to 0.91 for 5/5, where [E] of peregolo 0 is 4%. It has also been found that RP proportional to [E]0.58 for peregolo 0 and RP proportional to [E]0.51 for emulsifier OP. In order to interpret the results sufficiently, both micellar nucleation and micro-droplet nucleation have been taken into account for the emulsion polymerization of the present system irradiated without agitation, especially for the case with a higher M/W value the later may be the main nucleation process

  10. Hyperbaric oxygen therapy for radiation-induced hemorrhagic cystitis

    Energy Technology Data Exchange (ETDEWEB)

    Miyazato, Tomonori; Yusa, Toshiko; Onaga, Tomohiro; Sugaya, Kimio; Koyama, Yuzo; Hatano, Tadashi; Ogawa, Yoshihide [Ryukyus Univ., Nishihara, Okinawa (Japan). Faculty of Medicine

    1998-05-01

    Radiation therapy has widely been used for cancers in the pelvis. Radiation cystitis, one of the late complications, presents often as hemorrhagic cystitis, which is refractory to the conventional therapy and may threaten the patient`s life. We used hyperbaric oxygen therapy on patients with radiation cystitis to test its potential benefit. Ten patients aged from 46 to 81 years with a mean of 62 years underwent one or more courses of hyperbaric oxygen therapy according to their symptoms, consisting of 20 sessions (3 to 5 sessions a week) at the Department of Hyperbaric Medicine, the University of the Ryukyus Hospital in the 9-year period from 1985 to 1994. They included 8 patients having a history of cervical cancer, one with external genital cancer and one with vaginal cancer. During the 75 min hyperbaric oxygen therapy patients received 100% oxygen at 2 absolute atmosphere pressure in the Multiplace Hyperbaric Chamber. Hematuria subsided and subjective symptoms including urinary frequency improved in seven patients. Cystoscopic findings including mucosal edema, redness, and capillary dilation were partially improved. The procedure subjectively and objectively palliated the 10 patients in a favorable manner. To date we have not armed any active procedure to control radiation-induced refractory hemorrhagic cystitis in terms of efficacy, invasiveness, and adverse effects. Therefore, in consideration of our clinical results, hyperbaric oxygen therapy appears to be useful for radiation cystitis. (author)

  11. Radiation-induced defects in GaN

    Energy Technology Data Exchange (ETDEWEB)

    Son, N T; Hemmingsson, C G; Monemar, B; Janzen, E [Department of Physics, Chemistry and Biology, Linkoeping University, SE-581 83 Linkoeping (Sweden); Morishita, N; Ohshima, T [Japan Atomic Energy Agency, 1233 Watanuki, Takasaki, Gunma 370-1292 (Japan); Paskova, T; Evans, K R [Kyma Technologies Inc., 8829 Midway West Road, Raleigh, NC 27617 (United States); Usui, A [R and D Division, Furukawa Co., Ltd, Tsukuba, Ibaraki 305-0856 (Japan); Isoya, J, E-mail: son@ifm.liu.s [Graduate School of Library, Information and Media Studies, University of Tsukuba, 1-2 Kasuga, Tsukuba, Ibaraki 305-8550 (Japan)

    2010-11-01

    Radiation-induced defects in n-type GaN irradiated by 2 MeV electrons at room temperature were studied by electron paramagnetic resonance (EPR). Four EPR spectra, labelled D1-D4, were observed in irradiated n-type GaN. The D1 spectrum is a broad line ({approx}10-12 mT in line width) with an isotropic g-value g{approx}2.03 and can be detected in all the studied samples in the temperature range of 4-300 K. The D2 centre has an electron spin S=1/2 and shows a clear hyperfine structure due to interaction with three equivalent {sup 14}N. The g-values of the axial configuration are determined to be g{sub parallel}=2.001 and g{sub p}erpendicular=1.999. On the basis of the observed hyperfine structure, formation conditions and annealing behaviour, the D2 defect was assigned to the gallium vacancy-oxygen pair in the negative charge state, (V{sub Ga}O{sub N}){sup -}.

  12. Radiation induced oxidation of liquid alkanes as a polymer model

    International Nuclear Information System (INIS)

    Radiation induced oxidation of liquid n-hexadecane (n-C16H34) and squalane (C30H62) as a polymer model has been investigated by the measurements of the gas evolution and O2 uptake, and analyses of the oxidation products. Low O2 uptake, [G(-O2) ∼ 6.0] in liquid alkanes, indicates that the oxidation reaction does not exhibit chain kinetics, which is a big contrast to the process observed in solid, G(-O2) >> 10. H2 is the main gas product. More than 90% of the consumed O2 are converted into the oxidation products in liquid phase, mainly carboxylic acids, which is also a big contrast to the results of the radiolysis of liquid cyclohexane in the presence of O2 and thermal oxidation of hexadecane at elevated temperatures, where ketones and alcohols are major products at the initial stage. In the presence of aromatic additives, energy and charge transfer to the additives taking place despite the presence of O2 reduce the H2 evolution and the acid formation in parallel. Although hydroaromatic compounds act as an energy and charge scavenger, they are selectively oxidized through the donation of hydrogen in cyclic alkyl part attached to the phenyl ring, leading to large O2 uptake and corresponding ketone formation. From the comparison of the G-values of the O2 uptake, it was found that the oxidation reactions of liquid alkanes reflect well the oxidation of amorphous part in polymers. (author)

  13. Radiation-induced crosslinking of syndiotactic 1,2-polybutadiene

    International Nuclear Information System (INIS)

    Crystalline syndiotactic 1, 2-polybutadiene (hereafter abbreviated as 1, 2-PB) developed in Ube Industries, Ltd. by its own technology is a new thermoplastic resin belonging to the intermediate region between rubber and plastics in its flexibility. By selecting appropriate catalyst composition, 1, 2-PB having the melting point of 90 to 200 deg. C and crystallization of 10 to 65% can be obtained. These 1, 2-PBs can be worked to formed products by general thermoplastic forming methods such as injection molding, extrusion forming and blow forming. Radiation-crosslinked 1, 2-PB changed to very hard polymers through heat treatment. This change has been found to be radical chain reaction of cyclic polymerization. The relation of radiation-induced crosslinking and thermal expansion behavior, and the changes of appearance and structural and physical properties with heat treatment of these polymers are described. That is, specific gravity has increased, tensile strength has been enhanced, and elongation has decreased. While dielectric strength and arc resistivity have been upgraded. Therefore, these polymers can be used for the following applications: food wrapping film, molded notions, molded low foaming material for the soles of footwears, highly foaming moldings such as sponges, electric insulation material such as cable coating and adhesives for many materials. It is considered that crosslinking contributes to the application to electric insulation materials and heat curing to heat-resistant materials and parts. (Wakatsuki, Y.)

  14. Radiation induced thyroid neoplasms 1920 to 1987: A vanishing problem

    International Nuclear Information System (INIS)

    Radiation for benign diseases has been implicated as an etiologic factor in thyroid cancer. From 1930-60, over 2 million children may have been exposed to therapeutic radiation and it is estimated that up to 7% may develop thyroid cancer after a 5-40 year latency. Thyroid stimulating hormone, secondary to radioinduced hypothyroidism, has been implicated as causative in animals. Such data has led to expensive screening programs in high risk patients. Because of a decline in irradiation for benign diseases in children over the last 2 decades, we questioned whether the incidence of radiation induced thyroid neoplasms (RITN) was also decreasing. Twenty-six of 227 patients (11%) with thyroid malignancies seen at our institution from 1974-87 had a history of previous head and neck irradiation. These included 13 papillary, 3 follicular, and 7 mixed carcinomas as well as 2 lymphomas and 1 synovial cell sarcoma. None of these 26 patients had abnormal thyroid function tests at presentation. Mean latency from irradiation to the diagnosis of thyroid cancer was 25.4 years (6-55 year range). Compared to the reported increasing incidence of RITN from 1940-70, there appears to be a significant decrease since 1970. Based on our analysis, the use of expensive screening programs in high risk populations may no longer be warranted. Additionally, the routine use of thyroid replacement in previously irradiated chemically hypothyroid patients is not recommended.30 references

  15. The process and promotion of radiation-induced cell death

    International Nuclear Information System (INIS)

    Radiation-induced cell death is divided into reproductive and interphase death, whose process can be revealed by time-lapse observations. Pedigree analyses of progenies derived from a surviving progenitor cell have shown that moribund cells appear in clusters among cells which are apparently undamaged (lethal sectoring). Sister cell fusion, which likely results from chromosome bridge, is the most frequently observed cell abnormality leading to reproductive death. While interphase death does not occur unless the dose exceeds 10 Gy for low LET radiation such as X-rays, high-LET radiation is very effective at inducing interphase death (RBE: ≅3 at 230 keV/μm). Expression or fixation of potentially lethal damage (PLD) is closely associated with cell cycle events and enhanced by inducing premature chromosome condensation (PCC) at a nonpermissive temperature in tsBN2 cells with a ts-defect in RCC1 protein (a regulator of chromatin condensation) which monitors the completion of DNA replication. Furthermore, higher-order structural changes in nuclear matrix such as induced by leptomycin B, an inhibitor of CRM1 (chromosome region maintenance) protein, also play an important role in the fixation of PLD. (author)

  16. Radiation-induced degradation of polysaccharide sodium alginate

    International Nuclear Information System (INIS)

    The radiation-induced degradation of sodium alginate by 60Co γ-rays was investigated in air at ambient temperature, and the change in their molecular weights was measured by multi-angle laser light scattering detector equipped with gel permeation chromatography (MALLS/GPC). The molecular weight of sodium alginate decreases with the increase of absorbed dose in the range of 0-60 kGy at the dose rate of 80 Gy/ min. The dispersion of molecular weight distribution of sodium alginate becomes narrow along with the absorbed dose. The weight-average molecular weight (Mw) changes from 321596.5 to 10024 when the absorbed dose increases from o kGy to 60 kGy. It is found that the degraded sodium alginate with molecular weight peak of 6000 is 83.22% of cumulative weight fraction. Anyway, the sodium alginate may have comprehensive application in the fields of agriculture, medicine and cosmetology as it can be absorbed well by biological tissue, if its weight-average molecular weight is below 10000. It is also found that new components will be contained in the products of sodium alginate degraded by irradiation. The further study dealing with the checking the biological safety and purification shall be performed. (authors)

  17. Radiation induced chemical reaction of carbon monoxide and hydrogen mixture

    International Nuclear Information System (INIS)

    Previous studies of radiation induced chemical reactions of CO-H2 mixture have revealed that the yields of oxygen containing products were larger than those of hydrocarbons. In the present study, methane was added to CO-H2 mixture in order to increase further the yields of the oxygen containing products. The yields of most products except a few products such as formaldehyde increased with the addition of small amount of methane. Especially, the yields of trioxane and tetraoxane gave the maximum values when CO-H2 mixture containing 1 mol% methane was irradiated. When large amounts of methane were added to the mixture, the yields of aldehydes and carboxylic acids having more than two carbon atoms increased, whereas those of trioxane and tetraoxane decreased. From the study at reaction temperature over the range of 200 to 473 K, it was found that the yields of aldehydes and carboxylic acids showed maxima at 323 K. The studies on the effects of addition of cationic scavenger (NH3) and radical scavenger (O2) on the products yields were also carried out on the CO-H2-CH4 mixture. (author)

  18. Radiation-induced secondary cancer in patients with uterine carcinoma

    International Nuclear Information System (INIS)

    In an effort to identify radiation-induced secondary cancer (RSC), data from 19,384 patients, which were treated for uterine carcinoma at seven institutions in Japan between 1960 and 1978, were statistically analyzed using a computer system. Treatment modalities included surgery alone (n = 6,655), radiation therapy and surgery (n = 4,310), and radiation therapy alone (n = 8,419). According to the criteria of Sakai et al., RSC was identified in 43 (0.3 %) of 12,729 patients receiving irradiation, including rectal cancer (14), leukemia (8), uterine corpus cancer (6), urinary bladder cancer (4), osteosarcoma or uterine sarcoma (3), sigmoid colon cancer or malignant fibrous histiocytoma (2), and ovarian cancer (one). When the risk of RSC for the rectum, the urinary bladder, and leukemia was analyzed using a person-years method, there was no statistically significant difference between the irradiated and non-irradiated patients. Therefore, three institutions were selected for further analysis with 2,686 patients (13,588 person-years), taking the effort and accuracy for follow-up of patients into account. The analysis showed statistically significant increase in RSC for the rectum and leukemia. It can thus be concluded that the accuracy for follow-up of patients is the most important factor in evaluating the incidence of RSC. (Namekawa, K.)

  19. Advance in clinical research of radiation-induced heart disease

    International Nuclear Information System (INIS)

    Radiation-induced heart disease (RIHD) is one of common late side effects derived by thoracic radiotherapy. RIHD is often subclinical and there is an extremely long clinical latent period between radiation therapy and the first clinical presentation of radiation injury, and it did not cause clinical attention for a long time. Until the 1990s, epidemiologic investigations demonstrate that thoracic cancer radiotherapy increased rates of cardiac mortality, RIHD has partly offset the survival benefit provided by adjuvant RT. Radiotherapy techniques has undergone many improvements over the last decades, these improvements decreased both the volume and dose of radiation delivered to the heart, seem to have decreased the incidence of RIHD. Nonetheless, recent studies indicate that the problem of RIHD may persist. For instance, patients with Hodgkin's Disease, lung cancer, and esophageal may still receive either a high dose of radiation to a small part of the heart or a lower dose to the whole heart in radiotherapy. Therefore, long-term cardiac followup of these patients is essential. This article briefly review the clinical presentations, influence factors, prevention and managements, diagnosis and study advances of RIHD. (authors)

  20. Prediction of radiation induced liver disease using artificial neural networks

    International Nuclear Information System (INIS)

    The objective of this study was to evaluate the efficiency of predicting radiation induced liver disease (RILD) with an artificial neural network (ANN) model. From August 2000 to November 2004, a total of 93 primary liver carcinoma (PLC) patients with single lesion and associated with hepatic cirrhosis of Child-Pugh grade A, were treated with hypofractionated three-dimensional conformal radiotherapy (3DCRT). Eight out of 93 patients were diagnosed RILD. Ninety-three patients were randomly divided into two subsets (training set and verification set). In model A, the ratio of patient numbers was 1:1 for training and verification set, and in model B, the ratio was 2:1. The areas under receiver-operating characteristic (ROC) curves were 0.8897 and 0.8831 for model A and B, respectively. Sensitivity, specificity, accuracy, positive prediction value (PPV) and negative prediction value (NPV) were 0.875 (7/8), 0.882 (75/85), 0.882 (82/93), 0.412 (7/17) and 0.987 (75/76) for model A, and 0.750 (6/8), 0.800 (68/85), 0.796 (74/93), 0.261 (6/23) and 0.971 (68/70) for model B. ANN was proved high accuracy for prediction of RILD. It could be used together with other models and dosimetric parameters to evaluate hepatic irradiation plans. (author)

  1. Radiation-induced cerebral cell apoptosis in rats

    International Nuclear Information System (INIS)

    Objective: To study the influence of radiation on rat cerebral cells including neurons and gliocytes. Methods: The rats were divided into control group and X-ray radiation groups with different doses. The apoptosis of cells at different time points after radiation was observed by optic microscopy, electron microscopy and DNA agarose gel electrophoresis. The double label method (in situ end-labeling of DNA strand breaks for labeling apoptotic cells, and immunohistochemistry for labeling cell type) was used to label apoptotic neurons and gliocytes cells separately. Results: The distinct morphological features of apoptosis and the DNA fragmentation ladders on agarose gel electrophoresis were seen in radiation groups. The rate of apoptosis in the adult rat brain was low. There were many apoptotic glial cells (about 93%) and a few apoptotic neurons (about 5%) after radiation. The apoptotic rate in high dose group was higher than that in low dose group. Conclusion: Apoptosis can be induced by radiation in rat brain, the apoptotic rate increases with a increasing dose in the range of 2-8 Gy. The gliocytes are more sensitive to radiation-induced apoptosis than the neurons

  2. Countermeasures for space radiation induced adverse biologic effects

    Science.gov (United States)

    Kennedy, A. R.; Wan, X. S.

    2011-11-01

    Radiation exposure in space is expected to increase the risk of cancer and other adverse biological effects in astronauts. The types of space radiation of particular concern for astronaut health are protons and heavy ions known as high atomic number and high energy (HZE) particles. Recent studies have indicated that carcinogenesis induced by protons and HZE particles may be modifiable. We have been evaluating the effects of proton and HZE particle radiation in cultured human cells and animals for nearly a decade. Our results indicate that exposure to proton and HZE particle radiation increases oxidative stress, cytotoxicity, cataract development and malignant transformation in in vivo and/or in vitro experimental systems. We have also shown that these adverse biological effects can be prevented, at least partially, by treatment with antioxidants and some dietary supplements that are readily available and have favorable safety profiles. Some of the antioxidants and dietary supplements are effective in preventing radiation induced malignant transformation in vitro even when applied several days after the radiation exposure. Our recent progress is reviewed and discussed in the context of the relevant literature.

  3. Radiation induced thyroid neoplasms 1920 to 1987: A vanishing problem

    Energy Technology Data Exchange (ETDEWEB)

    Mehta, M.P.; Goetowski, P.G.; Kinsella, T.J.

    1989-06-01

    Radiation for benign diseases has been implicated as an etiologic factor in thyroid cancer. From 1930-60, over 2 million children may have been exposed to therapeutic radiation and it is estimated that up to 7% may develop thyroid cancer after a 5-40 year latency. Thyroid stimulating hormone, secondary to radioinduced hypothyroidism, has been implicated as causative in animals. Such data has led to expensive screening programs in high risk patients. Because of a decline in irradiation for benign diseases in children over the last 2 decades, we questioned whether the incidence of radiation induced thyroid neoplasms (RITN) was also decreasing. Twenty-six of 227 patients (11%) with thyroid malignancies seen at our institution from 1974-87 had a history of previous head and neck irradiation. These included 13 papillary, 3 follicular, and 7 mixed carcinomas as well as 2 lymphomas and 1 synovial cell sarcoma. None of these 26 patients had abnormal thyroid function tests at presentation. Mean latency from irradiation to the diagnosis of thyroid cancer was 25.4 years (6-55 year range). Compared to the reported increasing incidence of RITN from 1940-70, there appears to be a significant decrease since 1970. Based on our analysis, the use of expensive screening programs in high risk populations may no longer be warranted. Additionally, the routine use of thyroid replacement in previously irradiated chemically hypothyroid patients is not recommended.30 references.

  4. Solvent influence during radiation induced grafting of styrene in PVDF

    International Nuclear Information System (INIS)

    Radiation-induced grafting was studied to produce styrene grafted poly(vinylidene fluoride) (PVDF) membranes. PVDF films with 0.125 mm thickness were irradiated at doses between 5 and 20 kGy in the presence of styrene/N,N-dimethylformamide (DMF), styrene/acetone or styrene/toluene solutions (1:1, v/v) at dose rate of 5 kGy h-1 by simultaneous method, using gamma rays from a Co-60, under nitrogen atmosphere and at room temperature. The films were characterized before and after modification by grafting yield (GY %), infrared spectroscopy (FT-IR), scanning electron microscopy (SEM and EDS), differential scanning calorimetry (DSC) and thermogravimetry (TG/DTG). GY results shows that grafting increases with dose and toluene hinders the grafting, leading to a small GY comparing to DMF and acetone. It was possible to confirm the grafting of styrene by FT-IR due to the new characteristics peaks and by the TG and DSC due to changes in thermal behavior of the grafted material. SEM and EDS show surface and cross-section distribution of the grafting, which takes place on the surface and heterogeneously with toluene as solvent and homogeneously and penetrating into the inner layers of the matrix using DMF and acetone as solvent. (author)

  5. Radiation-induced defect formation in lithium sulfate crystals

    International Nuclear Information System (INIS)

    The study on the crystalline water effect on the radiation-induced processes is carried out in the Li2SO4 · H2O monocrystal samples, grown from the saturated water solution through the method of the solvent isothermal evaporation. The highly-pure source material was purified through the preliminary recrystallization. The Li2SO4 · H2O monocrystals dehydration was accomplished at 600 deg C during one hour. The powder-like samples were obtained after thermal treatment. The irradiation was conducted by the URS-55a X-ray apparatus (Cu-anticathode, U = 35 kV, I 10 mA). Measurements of the thermo-induced luminescence (TIL) curves were performed by the standard methods. The predominant peak of the recombination luminescence has the maximum in the area of 95 K. The luminescence in the area of 95 K is connected with the defects decomposition in the crystalline water subsystem. The products of the water molecules radiolysis significantly effect the recombination processes in the sulfate subsystem

  6. Radiation-induced hypoxia may perpetuate late normal tissue injury

    International Nuclear Information System (INIS)

    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

  7. Space-radiation-induced Photon Luminescence of the Moon

    Science.gov (United States)

    Wilson, Thomas; Lee, Kerry

    2008-01-01

    We report on the results of a study of the photon luminescence of the Moon induced by Galactic Cosmic Rays (GCRs) and space radiation from the Sun, using the Monte Carlo program FLUKA. The model of the lunar surface is taken to be the chemical composition of soils found at various landing sites during the Apollo and Luna programs, averaged over all such sites to define a generic regolith for the present analysis. This then becomes the target that is bombarded by Galactic Cosmic Rays (GCRs) and Solar Energetic Particles (SEPs) above 1 keV in FLUKA to determine the photon fluence albedo produced by the Moon's surface when there is no sunlight and Earthshine. This is to be distinguished from the gamma-ray spectrum produced by the radioactive decay of radiogenic constituents lying in the surface and interior of the Moon. From the photon fluence we derive the spectrum which can be utilized to examine existing lunar spectral data and to design orbiting instrumentation for measuring various components of the space-radiation-induced photon luminescence present on the Moon.

  8. Radiation induced modification of polyurethane for biomedical applications

    International Nuclear Information System (INIS)

    The polyether urethane WH8 was modified by radiation induced grafting Biocompatibility was achieved using hydrophil or hydrophil made monomers. Grafting of the monomers HEMA, GMA, GOMA and AAm onto the polyether urethane was performed by means of preswelling technique. By variation of preswelling time and irradiation dose different degrees of grafting were obtained. The grafted products were characterized by IR-Spectroscopy and the deepness of grafting was determined for the systems WH8-g-HEMA, WH8-g-GMA and WH8-g-AAm. Mechanical properties of the basis polymer and the grafted samples were measured by tension-extension experiments in the dry and waterswelled state. To the systems WH8-g-GMA and WH8-g-AAm hydrophil groups as the diol and the sulfonic group were attached by chemical reactions. The content of water of modified samples was determined and rose with increasing degree of grafting. To characterize the surface the contact angle against water (THETAsub(H2O)) and octane (THETAsub(octane)THETAsub(H2O)) was determined and therefrom the free boundary surface energy (#betta#sw) between the polymer and water. Increasing the degree of grafting adsorption of albumine rises strongly with all systems. Cell culture tests and biocompatibility tests were positive with one exception. The influence of the samples on the intravasal curdling system was determined by measuring recalcification time after incubation in human plasm. (SPI)

  9. Interleukin-32 Positively Regulates Radiation-Induced Vascular Inflammation

    International Nuclear Information System (INIS)

    Purpose: To study the role of interleukin-32 (IL-32), a novel protein only detected in human tissues, in ionizing radiation (IR)-induced vascular inflammation. Methods and Materials: Irradiated (0-6 Gy) human umbilical vein endothelial cells treated with or without various agents-a cytosolic phospholipase A2 (cPLA2) inhibitor, a cyclooxygenase-2 (Cox-2) inhibitor, or lysophosphatidylcholines (LPCs)-were used to assess IL-32 expression by Northern blot analysis and quantitative reverse transcriptase-polymerase chain reaction. Expression of cell adhesion molecules and leukocyte adhesion to endothelial cells using human acute monocytic leukemia cell line (THP-1) cells was also analyzed. Results: Ionizing radiation dramatically increased IL-32 expression in vascular endothelial cells through multiple pathways. Ionizing radiation induced IL-32 expression through nuclear factor κB activation, through induction of cPLA2 and LPC, as well as induction of Cox-2 and subsequent conversion of arachidonic acid to prostacyclin. Conversely, blocking nuclear factor κB, cPLA2, and Cox-2 activity impaired IR-induced IL-32 expression. Importantly, IL-32 significantly enhanced IR-induced expression of vascular cell adhesion molecules and leukocyte adhesion on endothelial cells. Conclusion: This study identifies IL-32 as a positive regulator in IR-induced vascular inflammation, and neutralization of IL-32 may be beneficial in protecting from IR-induced inflammation.

  10. Amifostine (WR2721) Drug Controls Radiation Induced Damage in Rats

    International Nuclear Information System (INIS)

    Amifostine is a pro-drug in which selectivity is largely determined by the preferential formation and uptake of its cytoprotective metabolite, WR-1065, in normal tissues as a result of differences in membrane-bound alkaline phosphatase activity. Animals were categorized into four groups as follows: control group, WR-2721-intraperitoneally injected group at a dose of 100 mg/ kg, 1.5 Gy gamma-irradiated groups for 5 days (day post day) receiving final dose up to 7.5 Gy and WR-2721 injected group at 30 minutes before exposing to every fractionated dose of gamma-irradiation. Animals were sacrificed after 7 and 16 days after the final exposure to gamma-irradiation. The results obtained showed increased levels of plasma creatinine, plasma urea, plasma total protein, alanine and aspartate aminotransferases (ALT and AST), alkaline phosphatase (ALP), total bilirubin and gamma glutamyle transferase (gamma GT) and decreased levels of Albumin/ Globulin ratio (NG) in irradiated animal group compared with the control one. Administration of Amifostine before radiation exposure has significantly improved the radiation-induced changes in all these tested parameters. It could be concluded that application of Amifostine may minimize radiation damage and attenuate the side effects resulted from radiotherapy exposure

  11. Radiation-induced-radioresistance: mechanisms and modification radioprotection

    International Nuclear Information System (INIS)

    Full text: The term radiation-induced-radioresistance (RIR) has been chosen to explain a particular class of resistance against lethal doses of radiation, which is transient and is induced by pre-exposure to low doses of radiation. This is a genetically governed phenomenon and is different from adaptation which in one of its several senses, refers to evolutionary transformation into new behavioural patterns. RIR is understood to be an evolutionarily conserved fundamental cellular defense mechanism. Small doses of radiation acting as stress stimuli evoke a concerted action of molecular pathways which help the organism to cope-up with the genotoxic effects of lethal doses of radiation given subsequently. Such molecular pathways are a complex interplay of genetic and biochemical entities and are increasingly becoming the focus of research world over. Most of our information on this subject has been gathered from prokaryotes, simpler eukaryotes, human cells and the epidemiological studies. A number of genes such as GADD 45, CDKN1A, PBP74, DIR1, DDR have been reported by to participate in RIR. However, till date, the mechanism of RIR remain poorly understood. In this deliberation some of our findings on mechanisms of RIR will be presented. Further, modification of RIR by a metabolic modifier, presently under clinical investigations for tumor radiotherapy, will also be presented

  12. Early corticosteroid administration in experimental radiation-induced heart disease

    International Nuclear Information System (INIS)

    The ability of dexamethasone (DEX) to reduce the severity of the late stage of radiation-induced heart disease (RIHD) was assessed in 25 New Zealand white rabbits. Ten rabbits served as unirradiated controls (CONT). In Group A, seven rabbits received intravenous DEX prior to irradiation and every 24 hours for three consecutive days. DEX was not administered to the eight rabbits in Group B. At 100 days postirradiation, the severity of the late state was determined by microscopic examination (MICRO) for myocardial fibrosis and determination of myocardial hydroxyproline content (MHP). Myocardial fibrosis was evident in groups A (40%) and B (80%) while none was present in CONT by MICRO. One rabbit in Group B with no fibrosis by MICRO had abnormally increased MHP. MHP was significantly increased in Groups A and B, as compared to CONT (p < 0.01). In addition to less fibrosis by MICRO, Group A demonstrated a significant reduction of MHP when compared to Group B (p < 0.05). Determination of MHP may be superior to MICRO in the detection of the late stage of RIHD. Also, early DEX administration appears to reduce myocardial collagen content (fibrosis) in this experimental model

  13. Radiation Induced Cystitis and Proctitis - Prediction, Assessment and Management.

    Science.gov (United States)

    Mallick, Supriya; Madan, Renu; Julka, Pramod K; Rath, Goura K

    2015-01-01

    Cystitis and proctitis are defined as inflammation of bladder and rectum respectively. Haemorrhagic cystitis is the most severe clinical manifestation of radiation and chemical cystitis. Radiation proctitis and cystitis are major complications following radiotherapy. Prevention of radiation-induced haemorrhagic cystitis has been investigated using various oral agents with minimal benefit. Bladder irrigation remains the most frequently adopted modality followed by intra-vesical instillation of alum or formalin. In intractable cases, surgical intervention is required in the form of diversion ureterostomy or cystectomy. Proctitis is more common in even low dose ranges but is self-limiting and improves on treatment interruption. However, treatment of radiation proctitis is broadly non-invasive or invasive. Non-invasive treatment consists of non-steroid anti-inflammatory drugs (NSAIDs), anti-oxidants, sucralfate, short chain fatty acids and hyperbaric oxygen. Invasive treatment consists of ablative procedures like formalin application, endoscopic YAG laser coagulation or argon plasma coagulation and surgery as a last resort. PMID:26320421

  14. Radiation-induced chromosomal instability in human mammary epithelial cells

    Science.gov (United States)

    Durante, M.; Grossi, G. F.; Yang, T. C.

    1996-01-01

    Karyotypes of human cells surviving X- and alpha-irradiation have been studied. Human mammary epithelial cells of the immortal, non-tumorigenic cell line H184B5 F5-1 M/10 were irradiated and surviving clones isolated and expanded in culture. Cytogenetic analysis was performed using dedicated software with an image analyzer. We have found that both high- and low-LET radiation induced chromosomal instability in long-term cultures, but with different characteristics. Complex chromosomal rearrangements were observed after X-rays, while chromosome loss predominated after alpha-particles. Deletions were observed in both cases. In clones derived from cells exposed to alpha-particles, some cells showed extensive chromosome breaking and double minutes. Genomic instability was correlated to delayed reproductive death and neoplastic transformation. These results indicate that chromosomal instability is a radiation-quality-dependent effect which could determine late genetic effects, and should therefore be carefully considered in the evaluation of risk for space missions.

  15. Gamma radiation induces hydrogen absorption by copper in water

    Science.gov (United States)

    Lousada, Cláudio M.; Soroka, Inna L.; Yagodzinskyy, Yuriy; Tarakina, Nadezda V.; Todoshchenko, Olga; Hänninen, Hannu; Korzhavyi, Pavel A.; Jonsson, Mats

    2016-04-01

    One of the most intricate issues of nuclear power is the long-term safety of repositories for radioactive waste. These repositories can have an impact on future generations for a period of time orders of magnitude longer than any known civilization. Several countries have considered copper as an outer corrosion barrier for canisters containing spent nuclear fuel. Among the many processes that must be considered in the safety assessments, radiation induced processes constitute a key-component. Here we show that copper metal immersed in water uptakes considerable amounts of hydrogen when exposed to γ-radiation. Additionally we show that the amount of hydrogen absorbed by copper depends on the total dose of radiation. At a dose of 69 kGy the uptake of hydrogen by metallic copper is 7 orders of magnitude higher than when the absorption is driven by H2(g) at a pressure of 1 atm in a non-irradiated dry system. Moreover, irradiation of copper in water causes corrosion of the metal and the formation of a variety of surface cavities, nanoparticle deposits, and islands of needle-shaped crystals. Hence, radiation enhanced uptake of hydrogen by spent nuclear fuel encapsulating materials should be taken into account in the safety assessments of nuclear waste repositories.

  16. Radiation induced grafting of acrylic acid onto extruded polystyrene surface

    International Nuclear Information System (INIS)

    Polystyrene materials with good solubility in liquid scintillation cocktails are used to wipe off different types of surfaces in order to determine the tritium removable contamination with the help of a liquid scintillation counter. This paper analyses hydrophilic surface modifications by radiation induced grafting of acrylic groups onto extruded polystyrene plates. Two grafting methods were used: (a) exposure of extruded polystyrene plates, immersed in aqueous acrylic acid solution, to a gamma radiation of a Co-60 source, and (b) exposure of extruded polystyrene plates to a Co-60 source, followed by the immersion of extruded polystyrene plates in aqueous acrylic acid solution. The grafting of acrylic was proved by IR spectrometry and by radiometric methods using acrylic acid labelled with tritium. - Highlights: ► Polystyrene (PS) is used to determine the removable surface contamination (RSC). ► RSC factor may be increased by PS surface modification. ► PS surface was modified by acrylic acid grafting using γ radiation 60Co source. ► Acrylic fragments insertion was determined by IR, and radiometric. ► Grafted PS discs increase RSC factor in the case of tritium contamination.

  17. Modification of synthetic fibers by radiation-induced grafting

    International Nuclear Information System (INIS)

    The present report describes studies to modify properties of synthetic fibers by radiation-induced grafting technique. This technique was employed since it is considered to be generally applicable to the grafting of a radically polymerizable monomer onto fiber. Three synthetic fibers were used mainly in the present studies; (1) polyester fiber which is ranked as the first in the amount of production in the synthetic fibers at present and is expected to increase in its importance in the future, (2) poly (vinyl chloride) fiber which is inexpensive and fire-retardant, and (3) polyethylene fiber which is not yet used in apparel at present. In order to perform the grafting, the following two methods were studied; one is to graft monomer uniformly in the fiber preventing homopolymerization of the monomer outside of the fiber, and the other to graft monomer only on the fiber surface. Using these methods, the following experiments were carried out and fairly good results as expected were obtained. (1) In the case of polyester fiber it was intended to make this more hydrophilic and fire-retardant. (2) Concerning to poly(vinyl chloride) fiber experiments were carried out to make the fiber more hydrophilic and simultaneously more heat-resistant. (3) In the case of polyethylene fiber, target was fire-retardance and heat-resistance. (author)

  18. Mechanisms of radiation-induced neoplastic cell transformation

    International Nuclear Information System (INIS)

    Studies with cultured mammalian cells demonstrated clearly that radiation can transform cells directly and can enhance the cell transformation by oncogenic DNA viruses. In general, high-LET heavy-ion radiation can be more effective than X and gamma rays in inducing neoplastic cell transformation. Various experimental results indicate that radiation-induced DNA damage, most likely double-strand breaks, is important for both the initiation of cell transformation and for the enhancement of viral transformation. Some of the transformation and enhancement lesions can be repaired properly in the cell, and the amount of irrepairable lesions produced by a given dose depends on the quality of radiation. An inhibition of repair processes with chemical agents can increase the transformation frequency of cells exposed to radiation and/or oncogenic viruses, suggesting that repair mechanisms may play an important role in the radiation transformation. The progression of radiation-transformed cells appears to be a long and complicated process that can be modulated by some nonmutagenic chemical agents, e.g., DMSO. Normal cells can inhibit the expression of transforming properties of tumorigenic cells through an as yet unknown mechanism. The progression and expression of transformation may involve some epigenetic changes in the irradiated cells. 38 references, 15 figures, 1 table

  19. Prevention of gamma radiation induced anaemia in mice by diltiazem

    International Nuclear Information System (INIS)

    Intraperitoneal administration of diltiazem (DTZ), half an hour prior to whole body gamma irradiation (2.5, 5.0, and 7.5 Gy), showed the protection of animals from radiation-induced anaemia. Radiation exposure significantly (p<0.001) reduced the number of pro- and normoblasts in bone marrow and red blood cell (RBC) counts, hemoglobin (Hb), hematocrit (Hct), and erythropoietin (EPO) level in blood, but increased myeloid/erythroid ratio. At all the radiation doses, the maximum decrease in these values was noted on the 3rd day, followed by a gradual recovery from the 7th day, but it was not recorded as normal even until the end of experimentation. In animals pretreated with DTZ, these values were measured higher at all the time periods in comparison to corresponding control, and these were almost normal at the last autopsy interval only at 2.5 Gy radiation dose. DTZ maintained the higher EPO level in blood, which acted on bone marrow and spleen colony forming unit for erythroblast (CFU-E), and stimulated such cells to produce RBCs. These results confirm that DTZ has the potency to alter anaemic condition favorably through the protection of bone marrow stem cells, and subsequently it maintains the higher number of pro-and normoblasts in bone marrow, RBC counts, Hb, Hct percentage, and EPO level in blood and the lower myeloid/erythroid ratio in bone marrow. (author)

  20. Real time in situ spectroscopic characterization of radiation induced cationic polymerization of glycidyl ethers

    Energy Technology Data Exchange (ETDEWEB)

    Mascioni, Matteo; Sands, James M.; Palmese, Giuseppe R

    2003-08-01

    Radiation curable polymeric materials suffer from relatively poor mechanical properties. Moreover, the curing behavior of such systems (i.e. the exact relationship between chemical kinetics and key processing variables) is not fully understood. In order to design improved epoxy based electron beam (EB) curable systems, and in order to develop appropriate process models, a detailed knowledge of the kinetics of epoxy cationic polymerization induced by ultraviolet (UV) or EB irradiation is required. In this work, we present our development of a technique based on real time near infrared (RTIR) spectroscopy for performing in situ kinetic analysis of radiation induced cationic polymerization of epoxy systems. To our knowledge this is the first time such data have been collected and presented for high-energy EB (10 MeV) induced polymerization. A demonstration of the technique for deterministic evaluation of degree of cure is shown using model glycidyl ether (phenyl glycidyl ether and diglycidyl ether of bisphenol A) resins and isothermal curing conditions. The impact of initiation rate on polymerizations with UV and EB for the cationic initiator is directly evident by comparative analysis. The sensitivity of the RTIR method and ability to produce quantitative data evidence of reaction mechanisms is demonstrated. The type of data presented in this work forms the basis for cure models being developed.

  1. Refinement of irradiation and analysis techniques for radiation-induced segregation

    Energy Technology Data Exchange (ETDEWEB)

    Allen, T.R.; Cookson, J.M.; Damcott, D.L.; Was, G.S. [Univ. of Michigan, Ann Arbor, MI (United States). Dept. of Nuclear Engineering and Radiological Sciences

    1997-11-01

    Radiation-induced segregation (RIS) has been implicated as a potential contributor to irradiation assisted stress corrosion cracking in light water reactor core components. To better understand changes to grain boundary chemistry during irradiation, RIS was measured in ultra-high purity (UHP) 304 stainless steel using Auger electron spectroscopy (AES). Variations in measured grain boundary concentration, both within a sample and between samples, are reduced by refinements in both the radiation and the AES techniques. These refinements include improvements in temperature control, uniformity of sample-to-sample dose, grain boundary acceptance criteria, amount of intergranular fracture, and amount of beam current uses in analysis. AES measurements on samples irradiated at 400 C to 1.0 dpa show how implementing the technique refinements reduces the variability in the measured concentrations. Additionally, measurements from regions of ductile tearing in samples irradiated to 0.1 and 1.0 dpa at 400 C, to 1.0 dpa at 200 C, and from unirradiated samples show that sensitivity factors must be determined to obtain the most accurate measurement of grain boundary composition.

  2. Protective effect of Nardostachys jatamansi on radiation induced anxiety and oxidative stress in mice

    International Nuclear Information System (INIS)

    Nardostachys jatamansi (family Valerianaceae), an indigenous medicinal plant induces in organism a state of resistance against stress. It helps to promote physical and mental health augment resistance of the body against disease and has shown potent antioxidant activity. To study the anxiolytic and protective effect of 100 mg of ethanolic extract of Nardostachys jatamansi was studied on the mice exposed to 6 Gy Electron beam radiation (EBR). The animals were treated with 100 mg of Nardostachys jatamansi extract (NJE) for 15 days before radiation exposure. The anxiety status of animals observed once for every 3 days during experiment period. The level of lipid peroxidation and glutathione (GSH) was estimated 15 days after irradiation. The irradiation of animals resulted in an elevation in anxiety, lipid peroxidation and reduction in GSH. Treatment of mice with NJE before irradiation caused a significant depletion in anxiety, lipid peroxidation followed by significant elevation in GSH. Our results indicate that the protective activity of NJE on radiation induced anxiety and oxidative stress may be due to free radical scavenging and increased antioxidant level in mice. (author)

  3. Role of Honey in Prevention of Radiation induced Mucositis in Head and Neck Cancer

    International Nuclear Information System (INIS)

    Objective: To determine the efficacy of honey in preventing radiation induced mucositis (RIM) in patients with head and neck cancers. Design: Randomized controlled trial. Setting: Oncology Department of Combined Military Hospital Rawalpindi, from July 2011 to September 2012. Patients and Methods: Sixty patients diagnosed with head and neck cancer requiring radiotherapy to the oropharyngeal mucosa were randomized into two groups to receive either radiation alone or radiation and natural honey. Patients were treated using 6-MV X-ray beams from linear accelerator at a dose rate of 2 Gy per day five times a week up to a dose of 66 Gy. In the treatment group, patients were advised to take 20 ml of pure honey 15 minutes before, 15 minutes after and 6 hours after radiotherapy. Patients were evaluated every week for the development of RIM using the WHO oral mucositis grading system. Results: In treatment group, out of 30 patients, 4(13%) developed grade 3 RIM and none developed grade 4 RIM. In control group, out of 30 patients, 12 (40%) developed grade 3 or 4 RIM (p=0.039). Four patients (13%) in treatment group lost more than 5 Kg weight during the course of radiotherapy compared to 16 patients (53%) in control group (p=0.002). Conclusion: The results of our study have shown that honey is a simple and cost effective treatment to prevent RIM. Large scale randomized trials are needed to confirm the results of our study. (author)

  4. Radiation-induced synthesis of Fe-doped TiO2: Characterization and catalytic properties

    International Nuclear Information System (INIS)

    Fe-doped TiO2 catalyst was prepared by wet impregnation, using TiO2 P25 Degussa as a precursor and Fe(NO3)3 as a dopant, followed by irradiation with an electron beam or γ-rays. Surface properties of Fe/TiO2 samples were examined by BET, XRD, ToF-SIMS, and TPR methods. The photocatalytic activity towards destruction of the anionic surfactant, sodium dodecylbenzenesulfonate (SDBS), in aqueous solutions was higher for the irradiated Fe/TiO2 catalysts than for bare TiO2 P25 or that calcined at 500 °C. The results show that irradiated catalysts exhibit a more uniform texture with high dispersion of iron species. An enhancement of the activity of irradiated Fe/TiO2 systems can be attributed to the synergetic effects of small crystallite size and homogenous distribution of iron species including FeTiO3 phase. - Highlights: ► Radiation-induced synthesis of iron-doped titania. ► Fe(NO3)3 as promoter of TiO2 P25 Degussa. ► Decomposition of dodecylbenzenesulfonate in aqueous solutions. ► Higher photocatalytic activity of irradiated Fe/TiO2 catalysts than that of calcined at 500 °C.

  5. Capabilities and limitations of analytical methods used to measure radiation-induced grain boundary segregation

    International Nuclear Information System (INIS)

    The quantitative determination of instrumental effects on the measurement of radiation-induced grain boundary segregation (RIS) in stainless steel have been irradiated with 3.4 MeV protons to 1 dpa at 400 degrees C and the resulting segregation has been measured by Auger electron spectroscopy (AES) and scanning-transmission electron microscopy using energy-dispersive x-ray spectroscopy (STEM-EDS). Depletion of chromium and enrichment of nickel and impurity elements at the grain boundaries have been observed and quantified using both techniques. Determination of true grain boundary compositions, as compared to measured compositions, has been attempted using a variety of techniques Deconvolution of the measured STEM profiles is possible, along with the effects of discrete sampling at finite step spacings render the technique incapable of a reliable determination of the true grain boundary compositions. Convolution of computer simulated segregation profiles with the beam-interaction volume to fit measured profiles provides a better method to estimate the true grain boundary concentration and segregation profile shape. Direct comparisons between the simulated STEM profiles and AES measurements show good agreement and indicate that the simulated profiles provide good estimates of the true grain boundary concentration. Use of computer codes based on the Perks model are shown to seriously overestimate the amount of RIS and the width of the segregation profiles. A calculational model for monolayer-type segregation of impurities combines the STEM and AES measurements to calculate the distribution of the impurity element at the grain boundary

  6. Nardostachys Jatamansi root extract protects of radiation induced glycogen depletion in Albino Wistar rats

    International Nuclear Information System (INIS)

    Exposure to ionizing radiation cause variety of pathological processes in irradiated cells. The killing action of ionizing radiation is mainly mediated through the free radicals generated from the radiolysis of cellular water. In the present study, protective effects of Nardostachys Jatamansi root extract (NJE) on radiation induced depletion of glycogen in rats exposed to 3 Gy whole body electron beam irradiation (EBR) was investigated. EBR was performed at Microtron centre, Mangalore University. Treatment of rats with NJE at a dosage of 100, 200 and 400 mg/kg bw respectively once daily for 15 days before, after and both before and after irradiation was done. The liver, kidney and muscle was separated and used for the estimation of total glycogen content using standard procedures and also for the histochemical localization of glycogen by PAS staining method. The data was analyzed by paired t test and Kruskal Wallis test. P<0.05 was the level of significance. The irradiated rats exhibited significant decline (p=0.000) in the level of total glycogen content in the tissues of liver, kidney and muscle whereas, a nonsignificant variation was recorded in rats treated with NJE. This study indicated that treatment with NJE both before and after irradiation for 15 consecutive days provided significant protection against irradiation induced depletion of glycogen. (author)

  7. Grading xerostomia by physicians or by patients after intensity-modulated radiotherapy of head-and-neck cancer

    International Nuclear Information System (INIS)

    Purpose: To assess observer-based vs. patient self-reported scoring of xerostomia after intensity-modulated radiotherapy (IMRT) of head-and-neck (HN) cancer. Methods: A total of 38 patients who had received IMRT for HN cancer underwent xerostomia evaluations 6 to 24 months after completion of therapy using three methods each time: (1) Grading by 3 observers according to the Radiotherapy Oncology Group/European Organization for Research and Therapy of Cancer (RTOG/EORTC) system; (2) patient self-reported validated xerostomia questionnaire (XQ); and (3) major salivary gland flow measurements. Results: The interobserver agreement regarding the RTOG/EORTC grades was moderate: κ-coefficient 0.54 (95% CI = 0.31-0.76). The correlations between the average RTOG/EORTC grades and the salivary flow rates were not statistically significant. A trend for significant correlation was observed between these grades and the percent (relative to the pretherapy) nonstimulated salivary flow rates (p = 0.07), but not with the percent stimulated flow rates. Better correlations were found between grading made more than the median time (15 min) after the last liquid sipping and the nonstimulated (but not the stimulated) flows compared with grading made shortly after sipping. In contrast, significant correlations were found between the XQ scores and the nonstimulated (p < 0.005) and the stimulated (p < 0.005) salivary flow rates, as well as with the percentages of the corresponding pretherapy values (p = 0.002 and 0.038, respectively). No significant correlation was found between the RTOG/EORTC grades and the XQ scores. The observer-based grades underestimated the severity of xerostomia compared with the patient self-reported scores. Conclusions: Patient self-reported, rather than physician-assessed scores, should be the main end points in evaluating xerostomia

  8. Erratum to "Clinical evaluation of the intraoral fluoride releasing system in radiation-induced xerostomic subjects. Part 2: Phase I study".

    Science.gov (United States)

    Chambers, Mark S; Fleming, Terence J; Toth, Béla B; Lemon, James C; Craven, Timothy E; Bouwsma, Otis J; Garden, Adam S; Espeland, Mark A; Keene, Harris J; Martin, Jack W; Sipos, Tibor

    2007-01-01

    Radiation-induced xerostomia can result in the rapid onset and progression of dental caries in head and neck cancer patients. Topically applied fluorides have been successfully used to inhibit the formation of dental caries in this population. However, because intensive daily self-application is required, compliance is an issue. The intraoral fluoride-releasing system (IFRS) containing a sodium fluoride core is a newly developed, sustained-release, passive drug delivery system that does not require patient involvement except for periodic replacement, thus reducing the effect of patient compliance on its effectiveness in dental caries prevention. Twenty-two head and neck cancer patients from U. T. M. D. Anderson Cancer Center, with radiation-induced xerostomia, were entered into a pilot study to contrast the daily home use of a 0.4% stannous fluoride-gel-containing tray (control group) to IFRS (study group) with respect to tolerability and adherence, and to obtain information on relative caries preventive efficacy. Participants were stratified on the basis of radiation exposure and randomly assigned to treatment with either IFRS or stannous fluoride gel. Patients in both groups were fitted with two IFRS retainers and also were instructed to use a 1100-ppm fluoride conventional sodium fluoride dentifrice twice daily. The study was conducted as a single-blinded, parallel-cell trial. Pre-existing carious lesions were restored prior to the beginning of the study. The efficacy variable was determined by the mean number of new or recurrent decayed surfaces. Patients were examined for caries 4, 8, 12, 24, 36, and 48 weeks after initiation of treatment. Reports of adverse reactions were based on information volunteered by patients and that were elicited during interviews. At baseline, the resting and stimulated salivary flow rates (g/5min) were significantly greater in the control group than in the study group (pIFRS groups during the study period. The rate of new or

  9. Identification of Radiation-Induced Segregation in Ion-irradiated Stainless Steel 316 using Atom Probe Tomography

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Gyeong-Geun; Jin, Hyung-Ha; Chang, Kunok; Kwon, Junhyun [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-10-15

    Various kinds of defects are produced by the irradiation of energetic particles onto a structural material. The defect fluxes such as mobile vacancies and self-interstitial atoms cause the diffusion of the solute atoms in the matrix. The preferential interaction of the solute with defects induces the enrichment or depletion of the solutes at the defect sinks such as the grain boundaries, and surfaces. These phenomena are generally known as radiation-induced segregation (RIS). Transmission electron microscopy (TEM) and energy dispersive X-ray spectroscopy (EDS) are generally used as basic analysis techniques to obtain a concentration profile of RIS arising from irradiation. However, the resolution of EDS is limited due to beam broadening, and the overlapping of the probed volume with the matrix prohibits a quantitative analysis of the concentration changes. In the current work, we introduced atom probe tomography (APT) to analyze RIS in SS 316. Various types of radiation-induced defects were identified and the compositional characteristics were quantitatively provided from a wide view point. The measured concentrations were compared with values in the literature. This work can provide a fundamental understanding of the RIS behavior in ion-irradiated SS 316. In this study, an APT analysis of RIS in ion-irradiated SS316 was performed. Various types of irradiation defects were observed. Si atoms are located at the core structures of dislocation loops and clusters.

  10. Dynamic measurements of radiation-induced electrical-property modifications in CVD-SiC under fast-neutron irradiation

    International Nuclear Information System (INIS)

    In situ measurements of the volume electrical conductivities of chemical-vapor-deposited silicon carbide (CVD-SiC) samples were carried out under irradiation by 2.5- and 14-MeV fast-neutron beams in air at room temperature. A slight radiation-induced conductivity (RIC) was detected under fast-neutron irradiation. A radiation-induced electrical degradation (RIED)-like behavior was observed in the form of degradation of the base conductivity in the absence of irradiation with increase in the fast-neutron fluence. The SEM micrograph images and XPS analysis of the surface of the fast-neutron-irradiated CVD-SiC samples revealed that the dissociation of carbon from existing SiOxC3−x compositions did not only occur via displacement damage, but also via ionizing effects (radiolysis), thereby leading to the observed RIED-like behavior as well as RIC in the electrical properties of the CVD-SiC samples

  11. Radiation-induced defects in tungsten and evolution in temperature: a positron annihilation spectroscopy study

    International Nuclear Information System (INIS)

    Full text of publication follows: In the future International Thermonuclear Experimental Reactor (ITER), tungsten, due to its physical intrinsic properties, such as low sputtering yield with light elements and good thermo-mechanical behaviour, is a potential divertor candidate. The divertor, as a plasma-facing component, will be subjected to intense irradiations at high temperature. In the specific case of fusion reactor, high 14 MeV neutrons flux will cause the continuous production of both H and He by (n,p) and (n,a) nuclear reactions, and of irradiation-induced defects by recoils. Thus, it appears of crucial interest to study the He and H interaction with the irradiation-induced defects. Obviously, this first requires to accurately characterise these defects. To address this issue, positron annihilation spectroscopy techniques were implemented, namely Doppler Broadening measurements with the use of a slow positron beam, and lifetime measurements with fast positrons. The presented results deal with the characterisation of irradiation-induced defects in tungsten, and also with its evolution during thermal treatment. Polycrystalline tungsten samples were first thermally annealed in order to eliminate most of the pre-existing defects so that detection of radiation-induced defects becomes possible. Then, specimens were irradiated with 12 MeV H at a 4x1016 cm-2 fluence or with 800 keV 3He at different fluences, ranging from 1014 to 1017 cm-2. The positron annihilation characteristics, namely low and high annihilation fractions and lifetimes, were determined in the annealed and irradiated samples. Moreover, Monte Carlo simulations were performed with the SRIM code to evaluate the radiation damage. Results allowed to identify the radiation-induced defects as mono-vacancies. Besides, it is shown that the defects nature does not change with increasing fluence, but their concentration increases. The evolution of the defects nature and concentration after thermal annealings

  12. Mechanism of enhancement of radiation-induced cytotoxicity by sorafenib in colorectal cancer

    International Nuclear Information System (INIS)

    Sorafenib, an orally available multikinase inhibitor, combined with radiation has shown potential as an anticancer treatment in an in vitro and in vivo colon cancer model. In this study, we investigated the mechanism of enhancement of radiation-induced cytotoxicity by sorafenib in colorectal cancer. The effects of sorafenib on radiation-induced cytotoxicity of DLD-1 and HT-29 were evaluated via clonogenic assay. The impact of sorafenib on radiation-induced cell cycle kinetics and on apoptosis was analyzed using flow cytometry. Cyclin B1 was examined by western blot. As a measure of DNA damage after treatment, γ-H2AX foci and nuclear fragmentation were determined as a function of time after irradiation plus sorafenib combination. Tumor growth delay was used to evaluate the effects of sorafenib on in vivo radiation-induced cytotoxicity. Exposure of each cell line to sorafenib combined with irradiation resulted in an increased radiation-induced cytotoxicity with dose enhancement factors at a surviving fraction of 0.37 ranging from 1.13 to 1.76. Sorafenib strengthened radiation-induced accumulation of tumor cells in the G2-M phase with attenuated expression of cyclin B1, but had no effect on radiation-induced apoptosis. Exposure to sorafenib and radiation resulted in a greater number of remaining γ-H2AX foci and fragmented nuclei than radiation alone. In vivo tumor xenograft study confirmed that administration of sorafenib results in significant tumor growth inhibition when combined with radiation. These results indicate that sorafenib enhances radiation-induced cytotoxicity in colorectal cancer and suggest that the mechanism is associated with delaying repair of radiation-induced DNA damage and down-regulation of cyclin B1. (author)

  13. Effect of epicatechin against radiation-induced oral mucositis: in vitro and in vivo study.

    Directory of Open Access Journals (Sweden)

    Yoo Seob Shin

    Full Text Available PURPOSE: Radiation-induced oral mucositis limits the delivery of high-dose radiation to head and neck cancer. This study investigated the effectiveness of epicatechin (EC, a component of green tea extracts, on radiation-induced oral mucositis in vitro and in vivo. EXPERIMENTAL DESIGN: The effect of EC on radiation-induced cytotoxicity was analyzed in the human keratinocyte line HaCaT. Radiation-induced apoptosis, change in mitochondrial membrane potential (MMP, reactive oxygen species (ROS generation and changes in the signaling pathway were investigated. In vivo therapeutic effects of EC for oral mucositis were explored in a rat model. Rats were monitored by daily inspections of the oral cavity, amount of oral intake, weight change and survival rate. For histopathologic evaluation, hematoxylin-eosin staining and TUNEL staining were performed. RESULTS: EC significantly inhibited radiation-induced apoptosis, change of MMP, and intracellular ROS generation in HaCaT cells. EC treatment markedly attenuated the expression of p-JNK, p-38, and cleaved caspase-3 after irradiation in the HaCaT cells. Rats with radiation-induced oral mucositis showed decreased oral intake, weight and survival rate, but oral administration of EC significantly restored all three parameters. Histopathologic changes were significantly decreased in the EC-treated irradiated rats. TUNEL staining of rat oral mucosa revealed that EC treatment significantly decreased radiation-induced apoptotic cells. CONCLUSIONS: This study suggests that EC significantly inhibited radiation-induced apoptosis in keratinocytes and rat oral mucosa and may be a safe and effective candidate treatment for the prevention of radiation-induced mucositis.

  14. Effects of helium and hydrogen on radiation-induced microstructural changes in austenitic stainless steel

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Hyung-Ha, E-mail: hhajin2@kaeri.re.kr; Ko, Eunsol; Lim, Sangyeop; Kwon, Junhyun

    2015-09-15

    Microstructural changes in austenitic stainless steel by helium, hydrogen, and iron ion irradiation were investigated with transmission electron microscopy. Typical radiation-induced changes, such as the formation of Frank loops in the matrix and radiation-induced segregation (RIS) or depletion at grain boundaries, were observed after ion irradiation. The helium ion irradiation led to the formation of cavities both at grain boundaries and in the matrix, as well as the development of smaller Frank loops. The hydrogen ion irradiation generated stronger RIS behavior at the grain boundaries compared to irradiation with helium and iron ions. The effects of helium and hydrogen on radiation-induced microstructural changes were discussed.

  15. Transient radiation-induced absorption in the materials for a GSGG laser

    Science.gov (United States)

    Brannon, P. J.

    1993-11-01

    Materials used in the optical elements of a 1,061 m GSGG (gadolinium scandium gallium garnet) laser have been tested for transient radiation-induced absorption. The transient radiation-induced absorption in KK1, Schott S7005 and S7010, and M382 glasses have been determined for discrete wavelengths in the range 440-750 nm. Also, the transient radiation-induced absorption in 'pure' and MgO doped LiNbO3 has been measured at 1,061 nm. Mathematical expressions composed of exponentials are fitted to the data.

  16. Transient radiation-induced absorption in the materials for a GSGG laser

    Energy Technology Data Exchange (ETDEWEB)

    Brannon, P.J.

    1993-11-01

    Materials used in the optical elements of a 1,061 m GSGG (gadolinium scandium gallium garnet) laser have been tested for transient radiation-induced absorption. The transient radiation-induced absorption in KK1, Schott S7005 and S7010, and M382 glasses have been determined for discrete wavelengths in the range 440--750 nm. Also, the transient radiation-induced absorption in {open_quotes}pure{close_quotes} and MgO doped LiNbO{sub 3} has been measured at 1,061 nm. Mathematical expressions composed of exponentials are fitted to the data.

  17. Effects of helium and hydrogen on radiation-induced microstructural changes in austenitic stainless steel

    International Nuclear Information System (INIS)

    Microstructural changes in austenitic stainless steel by helium, hydrogen, and iron ion irradiation were investigated with transmission electron microscopy. Typical radiation-induced changes, such as the formation of Frank loops in the matrix and radiation-induced segregation (RIS) or depletion at grain boundaries, were observed after ion irradiation. The helium ion irradiation led to the formation of cavities both at grain boundaries and in the matrix, as well as the development of smaller Frank loops. The hydrogen ion irradiation generated stronger RIS behavior at the grain boundaries compared to irradiation with helium and iron ions. The effects of helium and hydrogen on radiation-induced microstructural changes were discussed

  18. A systematic review of salivary gland hypofunction and xerostomia induced by cancer therapies

    DEFF Research Database (Denmark)

    Jensen, S.B.; Pedersen, A.M.L.; Vissink, A.;

    2010-01-01

    This systematic review aimed to assess the literature for prevalence, severity, and impact on quality of life of salivary gland hypofunction and xerostomia induced by cancer therapies. The electronic databases of MEDLINE/PubMed and EMBASE were searched for articles published in English since the...... 1989 NIH Development Consensus Conference on the Oral Complications of Cancer Therapies until 2008 inclusive. Two independent reviewers extracted information regarding study design, study population, interventions, outcome measures, results and conclusions for each article. The inclusion criteria were...... submandibular and minor salivary glands, as these glands are major contributors to moistening of oral tissues. Other cancer treatments also induce salivary gland hypofunction, although to a lesser severity, and in the case of chemotherapy and immunotherapy, the adverse effect is temporary. Fields of sparse...

  19. Radiation induced hepatic lesions and their amelioration by Rosemarinus oficinalis

    International Nuclear Information System (INIS)

    autopsy interval (i.e. 30 days), only in experimental group. On contrary, abnormal hepatocytes increased up to day 5 after irradiation. Binucleated hepatocytes showed a biphasic mode of elevation after irradiation, first on day 2 then on day 10 post-treatment in both the groups, but the same was comparatively less marked in experimental group. Several radiation induced hepatic lesions were also visualized in both the groups, but in ROE + radiation treated group, the degree of damage was found to be considerably lesser and the recovery from such lesions was much faster to regain the normal architecture of liver. Hence, the results from the present study suggest that Rosemarinus officinalis leaves extract pretreatment provides protection against radiation-induced histopathological alterations in liver of mammals. (author)

  20. Micronuclei: sensitivity for the detection of radiation induced damage

    International Nuclear Information System (INIS)

    The in vitro cytokinesis-block (CB) micronucleus (MN) assay for human peripheral blood has been used extensively for the assessment of chromosomal damage induced by ionizing radiation and chemicals and considered a suitable biological dosimeter for estimating in vivo whole body exposures, particularly in the case of large scale radiation accidents. One of the major drawbacks of the MN assay is its reduced sensitivity for the detection of damage induced by low doses of low LET radiation, due to the high variability among the spontaneous MN frequencies. It is suggested that age, smoking habit and sex are the main confounding factors that contribute to the observed variability. Previous work in our laboratory, shows a significant positive correlation of the spontaneous and radiation induced MN frequencies with age and smoking habit, the latter being the strongest confounder. These findings led to in vitro studies of the dose-response relationships for smoking and non smoking donors evaluated separately, using 60Co γ rays. The objectives of the present work are: 1-To increase the amount of data of the dose-response relationships, using γ rays from a 60Co source, for smoking and non smoking donors, in order to find, if applicable, a correction factor for the calibration curve that takes into account the smoking habit of the individual in the case of accidental overexposure dose assessment, particularly in the low dose range. 2-To establish general conclusions on the current state of the technique. The sample for smoking and non smoking calibration curves was enlarged in the range of 0Gy to 2Gy. The fitting of both curves, performed up to the 2Gy dose, resulted in a linear quadratic model. MN distribution among bi nucleated cells was found to be over dispersed with respect to Poisson distribution, the average ratio of variance to mean being 1.13 for non smokers and 1.17 for smokers. Each fitted calibration curve, for smoking and non smoking donors, fell within the 95

  1. Rosiglitazone attenuates pulmonary fibrosis and radiation-induced intestinal damage

    Energy Technology Data Exchange (ETDEWEB)

    Mangoni, M.; Gerini, C.; Sottili, M.; Cassani, S.; Stefania, G.; Biti, G. [Radiotherapy Unit, Clinical Physiopathology Department, University of Florence, Firenze (Italy); Castiglione, F. [Department of Human Pathology and Oncology, University of Florence, Firenze (Italy); Vanzi, E.; Bottoncetti, A.; Pupi, A. [Nuclear Medicine Unit, Clinical Physiopathology Department, University of Florence, Firenze (Italy)

    2011-10-15

    Full text of publication follows: Purpose.-The aim of the study was to evaluate radioprotective effect of rosiglitazone (RGZ) on a murine model of late pulmonary damage and of acute intestinal damage. Methods.- Lung fibrosis: C57 mice were treated with the radiomimetic agent bleomycin, with or without rosiglitazone (5 mg/kg/day). To obtain an independent qualitative and quantitative measure for lung fibrosis we used high resolution CT, performed twice a week during the entire observation period. Hounsfield Units (HU) of section slides from the upper and lower lung region were determined. On day 31 lungs were collected for histological analysis. Acute intestinal damage: mice underwent 12 Gy total body irradiation with or without rosiglitazone. Mice were sacrificed 24 or 72 h after total body irradiation and ileum and colon were collected. Results.- Lung fibrosis: after bleomycin treatment, mice showed typical CT features of lung fibrosis, including irregular septal thickening and patchy peripheral reticular abnormalities. Accordingly, HU lung density was dramatically increased. Rosiglitazone markedly attenuated the radiological signs of fibrosis and strongly inhibited HU lung density increase (60% inhibition at the end of the observation period). Histological analysis revealed that in bleomycin-treated mice, fibrosis involved 50-55% of pulmonary parenchyma and caused an alteration of the alveolar structures in 10% of parenchyma, while in rosiglitazone-treated mice, fibrosis involved only 20-25% of pulmonary parenchyma, without alterations of the alveolar structures. Acute intestinal damage: 24 h after 12 Gy of total body irradiation intestinal mucosa showed villi shortening, mucosal thickness and crypt necrotic changes. Rosiglitazone showed a histological improvement of tissue structure, with villi and crypts normalization and oedema reduction. Conclusion.- These results demonstrate that rosiglitazone displays a protective effect on pulmonary fibrosis and radiation-induced

  2. Rosiglitazone attenuates pulmonary fibrosis and radiation-induced intestinal damage

    International Nuclear Information System (INIS)

    Full text of publication follows: Purpose.-The aim of the study was to evaluate radioprotective effect of rosiglitazone (RGZ) on a murine model of late pulmonary damage and of acute intestinal damage. Methods.- Lung fibrosis: C57 mice were treated with the radiomimetic agent bleomycin, with or without rosiglitazone (5 mg/kg/day). To obtain an independent qualitative and quantitative measure for lung fibrosis we used high resolution CT, performed twice a week during the entire observation period. Hounsfield Units (HU) of section slides from the upper and lower lung region were determined. On day 31 lungs were collected for histological analysis. Acute intestinal damage: mice underwent 12 Gy total body irradiation with or without rosiglitazone. Mice were sacrificed 24 or 72 h after total body irradiation and ileum and colon were collected. Results.- Lung fibrosis: after bleomycin treatment, mice showed typical CT features of lung fibrosis, including irregular septal thickening and patchy peripheral reticular abnormalities. Accordingly, HU lung density was dramatically increased. Rosiglitazone markedly attenuated the radiological signs of fibrosis and strongly inhibited HU lung density increase (60% inhibition at the end of the observation period). Histological analysis revealed that in bleomycin-treated mice, fibrosis involved 50-55% of pulmonary parenchyma and caused an alteration of the alveolar structures in 10% of parenchyma, while in rosiglitazone-treated mice, fibrosis involved only 20-25% of pulmonary parenchyma, without alterations of the alveolar structures. Acute intestinal damage: 24 h after 12 Gy of total body irradiation intestinal mucosa showed villi shortening, mucosal thickness and crypt necrotic changes. Rosiglitazone showed a histological improvement of tissue structure, with villi and crypts normalization and oedema reduction. Conclusion.- These results demonstrate that rosiglitazone displays a protective effect on pulmonary fibrosis and radiation-induced

  3. Ionic process in radiation-induced degradation of polymers

    International Nuclear Information System (INIS)

    Poly (α-methylstyrene) powder was irradiated in vacuum at high temperature up to 200 deg C. The volatile products were collected in a cooled finger, and analyzed by gas chromatography. The results obtained were compared with those by pyrolysis at the same temperature and radiolysis at room temperature. One poly (α-methylstyrene) used was prepared by the radiation-induced cationic polymerization, and had the number-average molecular weight of 2.5 x 104, and the other was the anionic polymer having the average molecular weight of 1.5 x 106. The molecular weight of the polymers was reduced to about 1/2 of its initial values in the radiolysis at 200 deg C. On the other hand, when they were heated at 200 deg C without irradiation, the only product detected was a small amount of monomer, and the molecular weight of the polymers did not vary. In the radiolysis at room temperature, the product yields and the decrease in the molecular weight of the polymers were much smaller than those in the radiolysis at 200 deg C. In the pyrolysis of poly (α-methylstyrene), the polymer decomposed almost completely into monomer below about 400 deg C by the radical chain reaction involving unzipping process. In the radiolysis of hydrocarbons, the effect of the addition of cation scavengers such as amines, alcohols and ethers, which have larger proton affinity than hydrocarbons, was investigated in order to obtain evidence for the cationic processes of product formation. It appears that the product formation and the decrease in the molecular weight are suppressed by the addition of 5 wt.% of the additives. (Yamashita, S.)

  4. Radiation induced early onset of neuro-cognitive changes

    International Nuclear Information System (INIS)

    Exposure to ionizing radiations has been shown to cause many detrimental effects. Primarily, the effects observed are broadly classified into hematopoietic syndrome at lower doses, gastrointestinal syndrome and central nervous system dysfunctions at high doses. However, recent studies reported that even at lower doses, there is an effect seen on the nervous system which can be observed as a decline in cognitive abilities. This has been reported in patients undergoing radiotherapy. The cognitive decline, especially in young patients affects development and has been shown to persist for years after the therapy. Thus, the aim of this study was to study and consolidate the early effects of radiation exposure which result in behavioural alterations and cognitive decline. Since, radiation-induced early changes in behavioural functions are poorly understood, therefore, the present investigation aimed to conceptualize and design behavioural test batteries in order to systematically study the immediate alterations in behavioural function following irradiation with a-rays. The behavioural alterations were correlated to changes in the different area of brain like hippocampus, thalamus, hypothalamus and corpus callosum using Diffusion Tensor Imaging (DTI) studies. Present study reported profound changes in behaviour, as well as alterations in the morphology of the brain tissue as perceived by DTI, 48 hours after exposure to ionizing radiations. These changes need to be correlated and clarified further to understand the mechanisms behind the cognitive dysfunctions occurring immediately after radiation exposure as well as to find out a therapeutic window to counteract or reduce the effect of long term cognitive changes following irradiation. (author)

  5. Quantitative analysis of radiation-induced DNA deoxyribose oxidation products

    International Nuclear Information System (INIS)

    Deoxyribose oxidation plays an important role in the chemistry and biology of radical-mediated DNA damage beyond the simple interruption of the DNA backbone, including involvement in complex DNA lesions, cross-linking with DNA repair proteins and the formation of endogenous DNA adducts. This is illustrated by our discovery that 3'-phosphoglycolaldehyde residues, arising from 3'-oxidation of deoxyribose in DNA, form glyoxal and the glyoxal adduct of dG. Our research is driven by the lack of information about the spectrum and quantity of deoxyribose lesions in isolated DNA, human cells and tissues. This problem is compounded by the fact that oxidation of each of the five possible positions in deoxyribose can generate several unique damage products, most of which are toxic to cells. To this end, we have developed a sensitive GC/MS method to identify and quantify virtually all deoxyribose oxidation products in isolated DNA and in cells exposed to oxidizing agents under biological conditions. This method was applied to quantify 3'-phosphoglycolaldehyde residues in DNA oxidized by Fe-EDTA, gamma-radiation and alpha-particles with a detection limit of 30 femtomoles/sample corresponding to two phosphoglycolaldehyde molecules in 10?6 nucleotides for a 170 μg DNA sample. A 13C2 - labeled phosphoglycolaldehyde was used as internal standard. The method was verified by analysis of a synthetic, phosphoglycolaldehyde-containing oligonucleotide. It is widely believed that Fe-EDTA and gamma-radiation induce DNA damage by the formation of hydroxyl radicals and therefore we expected to see similar efficiencies in phosphoglycolaldehyde formation. However, the results reveal large differences in the efficiency of phosphoglycolaldehyde formation by these oxidants and suggest weaknesses in models relating DNA structure to chemical reactivity of DNA. An understanding of the relative quantities of various deoxyribose oxidation products will provide important insights into the basic

  6. Ionizing radiation induced cataract; Katarakt-Induktion durch ionisierende Strahlung

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, W.U. [Universitaetsklinikum Essen (Germany). Inst. fuer Medizinische Strahlenbiologie

    2013-07-01

    Until recently it was believed that the cataract (opacity of the eye lens) is a deterministic effect with a dose threshold of several Gray in dependence on the exposure conditions. Studies in Hiroshima and Nagasaki, in the vicinity of Chernobyl, of American radiologic technologists, astronauts, and patients after having received several computer tomographies of the head region, however, have shown that this assumption is not correct. It had been overlooked in the past that with decreasing dose the latency period is increasing. Therefore, the originally available studies were terminated too early. The more recent studies show that, in the case of a threshold existing at all, it is definitely below 0.8 Gy independently of an acute or a chronic exposure. All studies, however, include 0 Gy in the confidence interval, so that the absence of a dose threshold cannot be excluded. The German Commission on Radiological Protection (Strahlenschutzkommission, SSK) suggested therefore among others: targeted recording of the lens dose during activities which are known to be associated with possible significant lens exposure, examination of the lens should be included as appropriate in the medical monitoring of people occupationally exposed to radiation, if there is potentially high lens exposure, adoption of research strategies to develop a basic understanding of the mechanisms underlying radiation induced cataracts. The International Commission on Radiological Protection (ICRP) actually assumes a threshold dose of 0.5 Gy and, based on this assumption, has recommended in 2011 to reduce the dose limit for the eye lens from 150 mSv in a year to 20 mSv in a year for people occupationally exposed to ionising radiation. (orig.)

  7. Dosimetric Analysis of Radiation-induced Gastric Bleeding

    International Nuclear Information System (INIS)

    Purpose: Radiation-induced gastric bleeding has been poorly understood. In this study, we described dosimetric predictors for gastric bleeding after fractionated radiation therapy. Methods and Materials: The records of 139 sequential patients treated with 3-dimensional conformal radiation therapy (3D-CRT) for intrahepatic malignancies were reviewed. Median follow-up was 7.4 months. The parameters of a Lyman normal tissue complication probability (NTCP) model for the occurrence of ≥grade 3 gastric bleed, adjusted for cirrhosis, were fitted to the data. The principle of maximum likelihood was used to estimate parameters for NTCP models. Results: Sixteen of 116 evaluable patients (14%) developed gastric bleeds at a median time of 4.0 months (mean, 6.5 months; range, 2.1-28.3 months) following completion of RT. The median and mean maximum doses to the stomach were 61 and 63 Gy (range, 46-86 Gy), respectively, after biocorrection of each part of the 3D dose distributions to equivalent 2-Gy daily fractions. The Lyman NTCP model with parameters adjusted for cirrhosis predicted gastric bleed. Best-fit Lyman NTCP model parameters were n=0.10 and m=0.21 and with TD50 (normal) = 56 Gy and TD50 (cirrhosis) = 22 Gy. The low n value is consistent with the importance of maximum dose; a lower TD50 value for the cirrhosis patients points out their greater sensitivity. Conclusions: This study demonstrates that the Lyman NTCP model has utility for predicting gastric bleeding and that the presence of cirrhosis greatly increases this risk. These findings should facilitate the design of future clinical trials involving high-dose upper abdominal radiation.

  8. Analysis of radiation-induced genome alterations in Vigna unguiculata

    Directory of Open Access Journals (Sweden)

    van der Vyver C

    2011-09-01

    Full Text Available Christell van der Vyver1, B Juan Vorster2, Karl J Kunert3, Christopher A Cullis41Institute for Plant Biotechnology, Department of Genetics, University of Stellenbosch, Stellenbosch, South Africa; 2Department of Plant Production and Soil Science, and 3Department of Plant Science, Forestry and Agricultural Biotechnology Institute, University of Pretoria, Pretoria, South Africa; 4Case Western Reserve University, Department of Biology, Cleveland, OH, USAAbstract: Seeds from an inbred Vigna unguiculata (cowpea cultivar were gamma-irradiated with a dose of 180 Gy in order to identify and characterize possible mutations. Three techniques, ie, random amplified polymorphic DNA, microsatellites, and representational difference analysis, were used to characterize possible DNA variation among the mutants and nonirradiated control plants both immediately after irradiation and in subsequent generations. A large portion of putative radiation-induced genome changes had significant similarities to chloroplast sequences. The frequency of mutation at three of these isolated polymorphic regions with chloroplast similarity was further determined by polymerase chain reaction screening using a large number of individual parental, M1, and M2 plants. Analysis of these sequences indicated that the rate at which various regions of the genome is mutated in irradiation experiments differs significantly and also that mutations have variable “repair” rates. Furthermore, regions of the nuclear DNA derived from the chloroplast genome are highly susceptible to modification by radiation treatment. Overall, data have provided detailed information on the effects of gamma irradiation on the cowpea genome and about the ability of the plant to repair these genome changes in subsequent plant generations.Keywords: mutation breeding, gamma radiation, genetic mutations, cowpea, representational difference analysis

  9. Radiation induced degradation of PAHs in water solution

    International Nuclear Information System (INIS)

    By combustion of coal in the caloric electrical plants, steel industry etc. in addition to NOx, SO2/SO3 (acid rain precursors) a number of rather toxic polycyclic aromatic hydrocarbons, such as diphenyloxide, fluorene, fluoranthene, naphthalene, anthracene, benzo(a)pyrene etc. are formed. They are emitted with the flue gases into the atmosphere and by rain and snow they can be brought to the ground water. These substances are carcinogenic, even in very small concentration, namely from 3 x 10-2 (diphenyloxide) to 1 x 10-6 (benz(a)pyrene) mg/m3 flue gas. Moreover, these pollutants are strongly involved in the ozone depletion of the atmosphere. The present dissertation deals with the degradation of PAHs by ozonolysis, γ-ray treatment and combined γ-ray-ozone treatment in light alkaline aqueous solution. In order to establish the optimal conditions for radiation-induced degradation, studies on individual representative compounds of this group were carried out under various conditions - in aqueous, aerated media (formation of peroxyl radicals) as well as in such saturated with N2O (conversion of eaq- into OH). Diphenyloxide (DPO), Fluorene (FLU) and Fluoranthene (FA) were taken as models for this group of compounds. The yields of the major degradation products were determined by means of internal standards using HPLC. Fast kinetic measurements were carried out by pulsradiolysis. Summing up it can be stated that DPO, FLU and FA as well as the resulting toxic products can be completely decomposed. The best pathway is a combined treatment of radiation and ozone, followed by a radiation processing in the presence of air. The involved reaction mechanisms in the step-by-step degradation are rather complicated. Based on the obtained results are postulated probable reaction mechanisms for illustration and for better understanding of the manifold processes. (author)

  10. A case of radiation induced carcinoma of the cervical esophagus

    International Nuclear Information System (INIS)

    A patient with carcinoma of the cervical esophagus who visited a hospital with a complaint of difficulty in swallowing was reported. This patient was a 50 year old woman. It was 32 years since she had had external irradiation with x- ray over the neck for Basedow's disease at the age of 18. From the age of 30, she had had hypothyroidism and had used thyroid. She became aware of difficulty in swallowing in October, 1976. Then this symptom progressed gradually, and she also had hoarseness. She visited a hospital in August, 1977. At the first medical examination, pigmentation and atrophic changes in the neck induced by radiation were observed, and some lymphnodes with the size of a red bean were palpated. Esophageal roentogenography revealed circular and spiral type lesion in the cervical esophagus, which was 4 cm in length and had a clear boundary. Endoscopic examination revealed circular stenotic lesion. This lesion was diagnosed as squamous cell carcinoma by biopsy. Total of 3,000 rad of Linac x-ray was irradiated over the neck and the clavicle before operation. Operation findings revealed fibrosis, atrophy, and hardening of the thyroid gland caused by radiation. Carcinoma with the size 35 mm x 18 mm was limited to the cervical esophagus, and the degree of the progress was A2, N2, M0 (Pl0). Histological findings revealed moderately differentiated squamous cell carcinoma and its metastases to the right supraclaviclar lymphnodes. This carcinoma was diagnosed as radiation-induced carcinoma of the cervical esophagus, because this patient had had irradiation over the neck, locally marked atrophic changes and scar remained, and carcinoma occurred in the area which had been irradiated with x-ray. (Tsunoda, M.)

  11. Synthesis of EVA/MWNT nanocomposites by radiation induced crosslinking

    International Nuclear Information System (INIS)

    Full text: EVA is widely used as an insulating material for high voltage cables and in the footwear and toy industries due to its high flexibility and chemical inertness. The nano-composites of EVA with MWNT are of the special interest because incorporation of suitable amount of MWNT in EVA matrix is expected to significantly enhance EVA's thermal and mechanical properties, and open a new domain of applications. The modification of EVA by using high-energy radiation and with particulate filler has been widely practiced; however, there is not much information available on the radiation processing of EVA nanocomposites. To understand the effect of radiation and of MWNT addition on the physico-mechanical characteristics of EVA, different compositions of ethylene vinyl acetate (EVA)/multiple walled carbon nanotube (MWNT) nanocomposites were prepared by mixing in Brabender and subjected to different doses of gamma radiation. The efficiency of radiation vulcanization was analyzed by gel-content, Charlesby-Pinner parameter and crosslinking density measurements. Gamma radiation induced crosslinking was found to increase with MWNT fraction in EVA/MWNT nanocomposites (Po/qo range: 1.15-0.98). These results ruled out the possibility of a significant neutralization of single ionization spurs by MWNT addition. The polymer-filler interaction parameter determined from Kraus plot indicated good interaction between EVA and MWNTs. Storage modulus changed from 7 x 107 Pa to 1.8 x 108 Pa with incorporation of 5% (wt/wt) MWNT while density increased from 0.78 g/cc to 0.80 g/cc

  12. Radiation-induced preventive bystander response and adaptive response

    International Nuclear Information System (INIS)

    Radiation-induced bystander response (BR) is a phenomenon not observed in cells irradiated directly but in cells nearby. Recently, the relationship between BR and adaptive response (AR) has been studied and BR is suggested to be one of important mechanisms involved in AR induction through key molecules like reactive oxygen (RO) and nitrogen species. In this paper, the possible contribution of BR to AR is discussed on recent findings including author's ones. Many biological responses in bystander cells, cultured tissues and mice by cell-cell communication molecules such as cytokines and nitrogen oxide (NO) have been elucidated for BR to involve the cell death, sister chromatid exchange, chromosome instability, mutation, increased/ decreased p53 level, etc. However, BR has been recently found to contain biologically favorable events like the increase of radio-resistance and of cellular take rate and decrease of micronucleus formation through NO by X-ray and HIMAC C-ion. AR is observed in irradiated cell population with previous exposure to low dose and involves the above mentioned biologically favorable responses, which having lead to the possible interrelationship between BR and AR. Together with findings obtained hitherto, hypothesized is that AR is induced in bystander cells through a sequence of signals of evoked radicals like RO/ NO by pre-irradiation, and of consequent intermediating molecules like transforming growth factor (TGF)-1, tumor necrosis factor (TNF), interleukin (IL)-1 and estrogen to activate NF-KB for inducing COX-2 and NO synthase, which resulting in stimulation of damaged DNA repairing mechanism and of mitogen-activated protein kinase (MAPK) cascade that constructs the signaling between plasma membrane and nucleus. (K.T.)

  13. Curcumin Attenuates Gamma Radiation Induced Intestinal Damage in Rats

    International Nuclear Information System (INIS)

    Small Intestine exhibits numerous morphological and functional alterations during radiation exposure. Oxidative stress, a factor implicated in the intestinal injury may contribute towards some of these alterations. The present work was designed to evaluate the efficacy of curcumin, a yellow pigment of turmeric on y-radiation-induced oxidative damage in the small intestine by measuring alterations in the level of thiobarbituric acid reactive substances (TSARS), serotonin metabolism, catecholamine levels, and monoamine oxidase (MAO) activity in parallel to changes in the architecture of intestinal tissues. In addition, monoamine level, MAO activity and TSARS level were determined in the serum. Curcumin was supplemented orally via gavages, to rats at a dose of (45 mg/ Kg body wt/ day) for 2 weeks pre-irradiation and the last supplementation was 30 min pre exposure to 6.5 Gy gamma radiations (applied as one shot dose). Animals were sacrificed on the 7th day after irradiation. The results demonstrated that, whole body exposure of rats to ionizing radiation has induced oxidative damage in small intestine obvious by significant increases of TSARS content, MAO activity and 5-hydroxy indole acetic acid (5-HIAA) and by significant decreases of serotonin (5-HT), dopamine (DA), norepinephrine (NE) and epinephrine (EPI) levels. In parallel histopathological studies of the small intestine of irradiated rats through light microscopic showed significant decrease in the number of villi, villus height, mixed sub mucosa layer with more fibres and fibroblasts. Intestinal damage was in parallel to significant alterations of serum MAO activity, TBARS, 5-HT, DA, NE and EPI levels. Administration of curcumin before irradiation has significantly improved the levels of monoamines in small intestine and serum of irradiated rats, which was associated with significant amelioration in MAO activity and TBARS contents

  14. Radiation-induced apoptosis and developmental disturbance of the brain

    Energy Technology Data Exchange (ETDEWEB)

    Inouye, Minoru [Nagoya Univ. (Japan). Research Inst. of Environmental Medicine

    1995-03-01

    The developing mammalian brain is highly susceptible to ionizing radiation. A significant increase in small head size and mental retardation has been noted in prenatally exposed survivors of the atomic bombing, with the highest risk in those exposed during 8-15 weeks after fertilization. This stage corresponds to day 13 of pregnancy for mice and day 15 for rats in terms of brain development. The initial damage produced by radiation at this stage is cell death in the ventricular zone (VZ) of the brain mantle, the radiosensitive germinal cell population. During histogenesis of the cerebellum the external granular layer (EGL) is also radiosensitive. Although extensive cell death results in microcephaly and histological abnormlity, both VZ and EGL have an ability to recover from a considerable cell loss and form the normal structure of the central nervous system. The number of cell deaths to induce tissue abnormalities in adult brain rises in the range of 15-25% of the germinal cell population; and the threshold doses are about 0.3 Gy for cerebral defects and 1 Gy for cerebellar anomalies in both mice and rats. A similar threshold level is suggested in human cases in induction of mental retardation. Radiation-induced cell death in the VZ and EGL has been revealed as apoptosis, by the nuclear and cytoplasmic condensation, transglutaminase activation, required macromolecular synthesis, and internucleosomal DNA cleavage. Apoptosis of the germinal cell is assumed to eliminate acquired genetic damage. Once an abnormality in DNA has been induced and fixed in a germinal cell, it would be greatly amplified during future proliferation. These cells would commit suicide when injured for replacement by healthy cells, rather than undertake DNA repair. In fact they show very slow repair of cellular damage. Thus the high sensitivity of undifferentiated neural cells to the lethal effect of radiation may constitute a biological defense mechanism. (author) 69 refs.

  15. Proton beam therapy

    OpenAIRE

    Levin, W P; Kooy, H; Loeffler, J S; T. F. DeLaney

    2005-01-01

    Conventional radiation therapy directs photons (X-rays) and electrons at tumours with the intent of eradicating the neoplastic tissue while preserving adjacent normal tissue. Radiation-induced damage to healthy tissue and second malignancies are always a concern, however, when administering radiation. Proton beam radiotherapy, one form of charged particle therapy, allows for excellent dose distributions, with the added benefit of no exit dose. These characteristics make this form of radiother...

  16. Normal tissue complication probability model parameter estimation for xerostomia in head and neck cancer patients based on scintigraphy and quality of life assessments

    OpenAIRE

    Lee Tsair-Fwu; Chao Pei-Ju; Wang Hung-Yu; Hsu Hsuan-Chih; Chang PaoShu; Chen Wen-Cheng

    2012-01-01

    Abstract Background With advances in modern radiotherapy (RT), many patients with head and neck (HN) cancer can be effectively cured. However, xerostomia is a common complication in patients after RT for HN cancer. The purpose of this study was to use the Lyman–Kutcher–Burman (LKB) model to derive parameters for the normal tissue complication probability (NTCP) for xerostomia based on scintigraphy assessments and quality of life (QoL) questionnaires. We performed validation tests of the Quant...

  17. Patient- and therapy-related factors associated with the incidence of xerostomia in nasopharyngeal carcinoma patients receiving parotid-sparing helical tomotherapy

    OpenAIRE

    Tsair-Fwu Lee; Ming-Hsiang Liou; Hui-Min Ting; Liyun Chang; Hsiao-Yi Lee; Stephen Wan Leung; Chih-Jen Huang; Pei-Ju Chao

    2015-01-01

    We investigated the incidence of moderate to severe patient-reported xerostomia among nasopharyngeal carcinoma (NPC) patients treated with helical tomotherapy (HT) and identified patient- and therapy-related factors associated with acute and chronic xerostomia toxicity. The least absolute shrinkage and selection operator (LASSO) normal tissue complication probability (NTCP) models were developed using quality-of-life questionnaire datasets from 67 patients with NPC. For acute toxicity, the do...

  18. Yukmijihwang-tang for the treatment of xerostomia in the elderly: study protocol for a randomized, double-blind, placebo-controlled, two-center trial

    OpenAIRE

    Han, Gajin; Park, Jae-Woo; Ko, Seok-Jae; Son, Jihee; Seon, Jongki; Kim, Juyeon; Kim, Seulki; Yeo, Inkwon; Ryu, Bongha; Kim, Jinsung

    2013-01-01

    Background Xerostomia, a subjective sense of dry mouth, is not generally regarded a disease despite its high prevalence among the elderly, and therefore continues to impair affected patients’ quality of life. In traditional Korean medicine, ‘Yin-Deficiency’ has been implicated in the pathogenesis of xerostomia among the elderly. Yukmijihwang-tang is a famous herbal prescription used to relieve ‘Yin-Deficiency’, and reportedly has antioxidant effects; therefore, it is postulated that Yukmijihw...

  19. Quantitative model of radiation induced charge trapping in SiO2

    International Nuclear Information System (INIS)

    A predictive model of radiation induced oxide charging, based on statistical thermodynamics and electron spin resonance measurements of defects known as E' centers, has been developed. The model is successfully tested on 60Co irradiated MOSFETs

  20. Second primary tumor and radiation induced neoplasma in the uterine cancer

    Energy Technology Data Exchange (ETDEWEB)

    Sakurai, Tomoyasu; Nishio, Masamichi; Kagami, Yoshikazu; Murakami, Yoshitaka; Narimatsu, Naoto; Kanemoto, Toshitaka (National Hospital of Sapporo (Japan))

    1984-09-01

    This report is concerned with multiple primary cancers developing in invasive uterine cancer. Second primary tumors were recorded 27 women with a total of 30 non-uterine cancer (exception of radiation-induced cancer). 17 patients of radiation-induced neoplasm were observed (Rectal cancer 4, soft part sarcoma 4, cancer of urinary bladder 3, bone tumor 3, uterin cancer 2 and cancer of Vulva 1). One case is 4 legions (corpus, sigma, thymoma and stomach), 2 cases are 3 lesions (uterine cervix, stomach and maxillay siuis: uterine cervix, thyroidal gland and radiation-induced soft part sarcoma). Only 5 of these 17 patients were known irradiated dose (50 Gy--55 Gy), however others unknown. The mean latent periods of 17 cases of radiation induced neoplasms are 19.4 years. 16 patients of late second cancers of the cervix appearing from 11 to 36 years (average 19.5 years) after initial radiotherapy were recorded.