OTHERS_CITABLE Treatment of radiation-induced normal tissue lesions http://ijrr.com/article-1-10-en.pdf 2003-09-15 63 78 Normal tissue lesions steroids antiinflammatory drugs enzyme inhibitors antioxidants M. Rezvani mohi.rezvani@resin.ox.ac.uk 1 AUTHOR
ORIGINAL_ARTICLE Diffusion measurement in ferrous infused gel dosimeters Background: The compositions of Ferrous sulphate, Agarose and Xylenol orange dye (FAX) and Ferrous sulphate, Gelatin and Xylenol orange dye (FGX) in solution of distilled water and sulphuric acid are two tissue-equivalent gel dosimeters. Ionizing radiation causes oxidation of Fe2+ ion to Fe3+ ions which diffuse through the gel matrix and blur the image of absorbed dose over a period of hours after irradiation. Materials and methods: 25 mM sulphuric acid, 0.4 mM ferrous ammonium sulphate, 0.2 mM xylenol orange dye and 1% by weight agarose in distilled water named FAX and 0.1 mM ferrous ammonium sulphate, 0.1 mM xylenol orange dye, 50 mM sulphuric acid and 5% by weight gelatin in distilled water named FGX are used as two gel dosimeters. All chemicals were supplied by Sigma Aldridge Company, Germany . The gels were poured in Perspex casts and were irradiated to a beam of X ray from linear accelerators or x ray machine. Results: In this study diffusion coefficients of FAX and FGX dosimeters have been measured through a computer program for different temperatures. The ferric ion diffusion coefficient (D) for the FAX and FGX dosimeters were measured as (1.19 ± 0.03) x 10-2 cm2.hr-1 and (0.83 ± 0.03) x 10-2 cm2.hr-1 respectively at room temperature. Conclusion: For both dosimeters the diffusion coefficients decreased with gel storage temperatures down to 6oC. FGX dosimeters have advantage of lower diffusion coefficient for a specified temperature. Iran . J. Radiat. Res. 2003 1(2): 79 – 86. http://ijrr.com/article-1-11-en.pdf 2003-09-15 79 86 Chemical dosimeter gel dosimetry diffusion ferrous sulphate gels fricke gel dosimeter D. Shahbazi-Gahrouei shahbazi24@yahoo.com 1 AUTHOR
ORIGINAL_ARTICLE Annual background radiation in Chaharmahal and Bakhtiari province Background: Measurement of background radiation is very important from different points of view especially for human health. The aim of this survey was focused on determining the current background radiation in one of the highest altitude regions ( Zagros Mountains ), Chaharmahal and Bakhtiari province, in the south west of Iran . Materials and Methods: The outdoors-environmental monitoring exposure rate of radiation was measured in 200 randomly chosen regions using portable Geiger-Muller and Scintillation detectors. Eight measurements were made for each region and an average value was used to calculate the exposure rate from natural background radiation. Results: The exposure dose rate was found to be 28.4 m Rh-1 and the annual average effective equivalent dose was found to be 0.49 mSv. An overall population weighted average outdoor dose rate was calculated to be 49 nGyh-1, which is higher than the world-wide mean value of 44 nGyh-1 and is comparable to the annual effective equivalent dose of 0.38 mSv. Conclusion: A good correlation between the altitude and the exposure rate was observed, as the higher altitude regions have higher natural background radiation levels. Iran . J. Radiat. Res. 2003 1(2): 87 – 91. http://ijrr.com/article-1-12-en.pdf 2003-09-15 87 91 Background radiation annual effective dose Geiger-Muller and scintillation detectors altitude J. Salimi mjsalimi@sina.tums.ac.ir 1 AUTHOR K. Moosavi 2 AUTHOR S. Vatankhah 3 AUTHOR
ORIGINAL_ARTICLE The concentration of heavy trace elements in pigment and cholesterol humangallstones: Comparative studies by PIXE analysis. Background: The method of proton induced X-ray emission (PIXE) has been widely used as a sensitive technique to trace elemental analysis in both biological and medical fields. The sensitivity of this powerful method is in the order of ppm .The aim of this work is to analyze structural composition of 4 heavy trace elements with Z greater than 24 (Mn, Fe, Cu, Zn) in two kinds of gallstones and to compare the results for various ages of patients by PIXE quantitatively. Materials and methods: The pigment and cholesterole gallstones were obtained from 12 patients during surgical operations and were used for in vitro study. The age of the patients were between 22 and 78 years. Both cholesterol and pigmented types were analyzed for shell and center. The samples were bombarded using a 3.0 MeV van-de-Graff accelerator at nuclear research center of Atomic Energy Organization of Iran for the PIXE measurement. Results: In pigment gallstones, the mean value of Mn, Fe, and Zn in shell is greater than in the center and Cu in the shell is smaller than center. In cholesterol gallstones, neither in the shell nor in center, Zn was not observed. The composition of Mn and Fe in center is greater than in shell. In the patients older than 40 years, the concentration of heavy trace elements increases, and those in cholesterol stones are nearly two times larger than in pigment stones. Conclusion: Comparison of two types of gallstones shows that the center of the pigment stones is very similar to cholesterol type .It is concluded that the origination of gallstone in human is common but formation and growth are different. Iran . J. Radiat. Res. 2003 1(2): 93 – 97. http://ijrr.com/article-1-13-en.pdf 2003-09-15 93 97 Gallstone heavy trace elements PIXE M. Ghorbani 1 AUTHOR H. Mozdarani mozdarah@modares.ac.ir 2 AUTHOR
ORIGINAL_ARTICLE In vitro radioprotective effects of histamine H2 receptor antagonist against gamma-rays induced chromosomal aberrations in human lymphocytes. Background: Radioprotective capability of histamine H2 receptor antagonists have been shown in several in vivo studies mainly using animal models. However, to verify the effectiveness of these agents in clinical applications, studies should be performed on human cells. In the present study radioprotective properties of these agents was examined in vitro on human lymphocytes using metaphase analysis. Materials and Methods : In vitro metaphase analysis technique was used to test the effects of cimetidine, ranitidine and famotidine on radiation induced clastogenic effects. Lymphocytes in whole peripheral blood were exposed to 3 Gy gamma-rays at a dose rate of 73.7 cGy/min in the presence or absence of various doses of the drugs used in this study. The frequency of chromosomal aberrations were determined after standard metaphase preparations and staining slides in 5% Giemsa. Results: Results show that radiation produced a high number of chromosomal aberrations in lymphocytes compared to controls (p<0.001). All three drugs used in this study effectively reduced the frequency of chromosomal aberrations at all doses. Famotidine was found to be more effective than the other two drugs. Conclusion: From the results obtained it can be concluded that H 2 -receptor antagonists used in this study effectively reduced the clastogenic effects of radiation with a dose reduction factor (DRF) of 1.5-2 in human lymphocytes in vitro. The way in which these drugs reduce the clastogenic effects of radiation might be via radical scavenging mechanism. Iran . J. Radiat. Res. 2003 1(2): 99 – 104. http://ijrr.com/article-1-14-en.pdf 2003-09-15 99 104 H<sub>2</sub> receptor antagonists chromosomal aberration radioprotection human lymphocytes F. Farhan farshidfarhan@yahoo.com 1 AUTHOR A. Kazemian 2 AUTHOR H. Alagheband 3 AUTHOR
ORIGINAL_ARTICLE Topical betamethasone for the prevention of acute radiation dermatitis in breast cancer patients. Background: Acute radiation dermatitis is a very common side effect of radiation therapy in large numbers of cancers including breast cancer. Despite high prevalence rate of acute radiation dermatitis and also wet desquamation, a few trials on prophylaxis of this complication using topical treatment have been conducted. Despite effectiveness of topical corticosteroids in treatment of acute radiation dermatitis which are focused in the literature, yet there are some controversy about their usage in this regard. For this reason we attempted to investigate this subject via conducting a clinical trial. Materials and Methods: This trial included 76 patients with pathologic diagnosis of breast cancer for whom radiotherapy has been planned. Patients were 27-70 years old. Patients with radical mastectomy received 5000 cGy within 5 weeks, and those with conservative surgery received 6000 cGy within 6 weeks divided in 200 centigray fractions. Patients were divided randomly into two groups, betamethasone and placebo, 38 patients in each group. In placebo group, 3 patients did not attend for weekly assessment. Additional one patient did not refer during follow-up period. Thus, they were excluded from the study. One group was given betamethasone 0.1% and other group was administered base of ointment as placebo.All patients consumed drug or placebo from the 1st day of treatment until one week after treatment completion as twice daily within tangential field. Patients were monitored for assessing dermatitis severity and its symptoms and also possible drug adverse effects one week after the therapy commenced and afterwards by one-week intervals as well as in an appointed day. Three weeks after termination of therapy, patients were also visited, and each examination provided information about dermatologic complications which were registered in the questionnaire. Results: Mean times development of dermatitis in both betamethasone and placebo groups were 3.2500 and 2.2571 (weeks) respectively (t=-3.898 , p< 0.001). Maximal dermatitis intensity during treatment in betamethasone group was 3.5% 0, 86.8% I, 7.9% II, 0% III, 0% IV and in base of ointment receiving group were 0 %, 60% , 37.1%, 2.9% and 0% (P = 0.008), respectively. Maximum severity of complaints stated by patients in terms of burning and pruritus had been lesser in betamethasone group (P< 0.001). No significant differences were observed between two groups in terms of pain intensity. Conclusion: Betamethasone valerate ointment is statistically significantly more effective than base of ointment alone in reducing acute radiation dermatitis. Iran . J. Radiat. Res. 2003, 1(2): 105 – 111. http://ijrr.com/article-1-15-en.pdf 2003-09-15 105 111 Breast cancer dermatitis radiotherapy corticosteroids F. Solaimani fsoleimani@nmri-ir.com 1 AUTHOR M.H. Zahmatkesh 2 AUTHOR Sh. Akhlaghpoor 3 AUTHOR
ORIGINAL_ARTICLE Dental tissue as a TLD dosimeter Background: Thermoluminescence dosimetry is one of the dosimetry procedures used widely as routine and personal dosimeters. In order to extend this kind of dosimeters, dental tissue has been examined and was found promising as a TLD dosimeter. Materials and Methods : In this study, 70 health teeth were collected. The only criterion, which was considered for selection of the teeth, was the healthiness of them regardless of age and gender of the donors. All collected samples were washed and cleaned and milled uniformly. The final powder had a uniform grain size between 100 – 300 micrometer. The sample was divided into four groups. Group A and B were used for measurement of density and investigation of variation of thermoluminescent characteristics with temperature respectively. Groups C and D were used for investigation of variation of thermoluminescent intensity with dose and fading of this intensity with time . In all cases the results obtained with dental tissue were compared to a standard LiF, TLD dosimeter. Results : It was found that, average density of the dental tissue was 1.570 g/cm3, which is comparable to density of LiF, which is 1.612 g/cm3. It was also concluded that the range of 0-300 oC, dental tissue has a simple curve with two specific peaks at 140 and 250 oC respectively. The experiment also showed that, the variation of relative intensity versus dose is linear in the range of 0.04 – 0.1Gy . The fading rate of dental tissue is higher than LiF but still in the acceptable range (14% per month in compare to 5.2% per month) Conclusion : Dental tissue as a natural dosimeter is comparable with TLD and can be used in accidental events with a good approximation . Iran . J. Radiat. Res. 2003 1(2): 113 – 117. http://ijrr.com/article-1-16-en.pdf 2003-09-15 113 117 TLD dosimetry dental dosimetry personal dosimeters accidental dosimetry M. Mirzaii mmirzaii@aeoi.org.ir 1 AUTHOR H. Afarideh 2 AUTHOR S.M. Haji-Saeid 3 AUTHOR G.R. Aslani 4 AUTHOR M.R. Ensaf 5 AUTHOR
ORIGINAL_ARTICLE Production of [18F] fluoride with a high-current two layer spherical gold target Background: Fluoride-18 is the most widely used radioisotope for Positron Emission Tomography (PET). [18F] 2-flouro- 2-deoxy D-glucose (FDG) has become a standard tool in the area of clinical research. The oxygen-18 enriched water is the most widely used target for the production of fluoride-18. The use of the nuclear reaction 18O (p,n)18F has been found as the most effective method for the production of [18F] fluoride. Materials and methods: Gold is a chemically resistant metal, which has been found wide application in the chemical industry where it is often used in corrosive environments at high temperature.It is also one of the highest thermal conductivity of metals. A two layer-spherical gold chamber design was chosen to obtain a maximum pressure stability under high beam currents. The target body is consisted of two chambers, internal chamber for internal cooling and external chamber for enriched water target. Results: The target is irradiated with 28 MeV protons energy. The incident energy on the target chamber is 18 MeV. This target is operated without external over-pressure and has been tested for beam currents up to 60 μA. The measured target yield is 2655 MBq/μAh. There is found that saturation yield is 8.3 GBq/μA and shows 80% of theoretical yield. Conclusion: It was observed that gold is a good material for the construction of the target chamber, and also the spherical chambers are the best construction to bearing high pressure under high-current beam condition up to 60 μA. Iran . J. Radiat. Res. 2003 1(2): 119 – 124. http://ijrr.com/article-1-17-en.pdf 2003-09-15 119 124 Water target [18F] fluor FDG (PET) high current. A. Niroomand-Rad nirooma@gunet.georgetown.edu 1 AUTHOR