novel phantom design for brachytherapy quality assurance

Background: One major challenge in brachytherapy is to verify the accuracy of dose distributions calculated by the treatment planning system. In this project, a new phantom design has been introduced for quality assurance of dose distributions in gynocological [GYN] brachytherapy implants using EBT GafChromic film. Materials and Methods: This phantom has been designed and fabricated from 90 slabs of 18×16×0.2 cm[3] Perspex to accommodate a tandem and ovoids assembly, which is normally used for GYN brachytherapy treatment. In addition, this phantom design is allowing the use EBT GafChromic films for dosimetric verification of GYN implants with Cs-137 Selectron LDR system. With this assembly, GafChromic films were exposed using a plan designed to deliver 2.5 Gy dose to point "A" in Manchester system for tandem and ovoids configurations and to deliver 1.5 Gy of dose to 0.5 cm distance from the lateral surface of ovoids for using ovoid-pair. The measured dose distributions with GafChromic films were compared with the TPS isodose lines both numerically and spatially. For a quantitative analysis of the results, the measured doses values at several points of interest were evaluated with the treatment planning data and values obtained following the TG-43 dose calculation formalism. Results: The results of these investigations have indicated that the new phantom design enables us to measure differences of greater than +/-6% for LDR brachytherapy GYN treatments. Conclusion: The new phantom design could be utilized for the QA procedure of the brachytherapy remote after loading systems to confirm the accuracy of dose distribution in GYN implants

[Factors affecting the use of hearing protection devices among industrial workers of Sistan and Baluchestan province]

Background: One of the personnel's protection and control measures against injurious noise effects at work environment is the use of hearing protection devices [HPDs]

Objective: This study was performed to determine the factors affecting the use of HPDs

Methods: This cross-sectional study was carried out on 353 randomly selected industrial workers in Sistan and Baluchestan province who were exposed to more than 85 dB noise in 2009. Data were collected by using a validated questionnaire obtained from British Health and Safety Executive and analyzed by chi-square test

Findings: The mean employment history of participants was 9 +/- 5.8 years. Based on our data, 28.3% of industrial workers never used HPDs during their daily activities. The most common cause of failure [29.5%] to wear protection devices was associated with experiencing discomfort while using HPDs. There was a significant association between the workers' risk perception [P=0.05] and their knowledge [P=0.01] over the use of hearing protectors

Conclusion: According to our findings, it seems that promoting the workers' knowledge on risk perception associated with hearing loss and also improving the design of existing devices can lead to increased use of HPDs

Temporary and permanent level shifts in distortion product otoacoustic emissions following noise exposure in an animal model

Noise-induced hearing loss [NIHL] is one of the most common occupational illnesses. Most of the studies on NIHL were conducted at high noise levels that people are rarely exposed to but in industries. The function of the outer hair cells [OHCs] is impaired after exposure to industrial noise. Distortion product otoacoustic emissions [DPOAEs] are useful in examination of noise-induced level shifts. To assess the function of OHCs by DPOAE temporary and permanent level shifts [TLSdp and PLSdp] in rabbits exposed to white noise at realistic levels typically found in industrial settings over a broad range of frequencies. 12 albino rabbits were divided into two groups: the experimental group rabbits which were exposed to 95 dB SPL white noise at 500-8000 Hz for 8 hrs/day for 5 consecutive days, and the control group rabbits with no exposure to noise. The function of OHCs was examined by DPOAE level [Ldp] in different occasions. The study groups were compared for DPOAE temporary and permanent level shifts [TLSdp and PLSdp] to assess the effect of noise on OHCs function. Noise-induced DPOAE levels [Ldp] were decreased up to 20.65 dB [on day 8] and 18.93 dB [on day 11] at 5888.50 Hz [p=0.081]. TLSdp and PLSdp were significantly decreased up to 17.99 dB and 16.27 dB, respectively in the experimental group. The most and least Ldp were significantly different [p<0.05]; they occurred at 5888.50 and 588.00 Hz, respectively. There were significant differences between temporary and permanent threshold shift at various frequencies [p<0.05]. These differences were mainly related to 5888.50 Hz compared to other frequencies in each ear [p<0.05]. DPOAEs are an attractive tool for obtaining information about small temporary or permanent threshold shifts, even when the pure tone audiogram is normal

[Association between folate intake and breast cancer risk among Tehrani women: a case-control study]

Dietary folate deficiency may contribute to tumorogenesis in many sorts of malignancies. By considering the increasing incidence rate of breast cancer in Iran, this study was conducted to investigate the association between dietary folate intake and breast cancer risk. In this case-control study, 177 patients with breast cancer and 169 control subjects with no family history of malignancy were recruited from hospitals affiliated to Shahid-Beheshti University of Medical Sciences, Tehran. Standard questionnaires were used to collect data on demographic characteristics, physical activity, and food frequency consumption for the previous year. Total daily energy and folate intakes were estimated using the Nutritionist IV software. No statistically significant correlation was observed between daily dietary intake of folate and breast cancer risk in the sample population. However, the results showed a significant inverse association between daily intake of dietary folate and risk of breast cancer in postmenopausal women [OR=0.17; 95%CI: 0.035-0.88]. Increases in the strata of daily folate intakes were associated with decreasing trends of ORs in postmenopausal breast cancer risk [P[for trend] =0.036], where the OR of folate intake at the 2[nd] tertile was 0.26 [95%CI: 0.05-1.22] and at the 3[rd] tertile was 0.17 [95%CI: 0.035-0.88]. Based on the findings, folate intake was not correlated with breast cancer risk in the total sample population, whereas higher intakes of folate was inversely associated with postmenopausal breast cancer risk

Comparative study of smbr and extended aeration activated sludge processes in the treatment of strength wastewaters

One of the complete treatment processes for industrial and municipal wastewater treatment is membrane bioreactor process which has dominant potential in process and operation sections. This study was conducted to compare the performance of extended aeration activated sludge [EAAS] with submerged membrane bioreactor [SMBR] systems in the treatment of strength wastewater, in the same condition. The initial activated sludge was brought from the Plascokar Saipa wastewater plant. The Plexiglas reactor with effective volume of 758 L was separated by a baffle into the aeration and secondary sedimentation parts with effective volumes of 433 L and 325 L, respectively. The chemical oxygen demand [COD] concentration of the influent wastewater of the EAAS and SMBR systems were between 500-2700 and 500-5000 mg/L, respectively. Results showed that the SMBR system produced a much better quality effluent than EAAS system in terms of COD, biochemical oxygen demand [BOD5], total suspended solids [TSS] and ammonium. By increasing the COD concentration, the concentration of mixed liquor suspended solids [MLSS] and the removal efficiency of organic matter in the SMBR system, were increased regularly, however the removal efficiency of COD in the EAAS system was irregular. The average BOD5/COD ratio of effluent in the EAAS and SMBR systems were 0.708 +/- 0.18 and 0.537 +/- 0.106, respectively. These show that the organic matters in the effluent of the SMBR system was less degradable and thereupon more biological treatment was achieved. Nitrification process was completely done in the SMBR system while the EAAS system could not achieve to complete nitrification

[Performance evaluation of hybrid septic tank and aerated lagoon process efficiency for landfill leachate treatment]

In this research, landfill leachate treatment in Karaj city was investigated by a linked septic tank and aerated lagoon. At first, characteristics of the leachate were determined. Then a pilot plant with anaerobic-aerobic [Septic tank and Aerated lagoon] parts was installed and started. Results showed that Chemical Oxygen Demand [COD] removal efficiency for septic tank and subsequently to lagoon for influent COD of 19537 mg/L, were 8401 and 432 mg/L, respectively. The septic tank and aerated lagoon also operated with different flow rates and the best results for septic tank and aerated lagoon obtained in 23.6 L/day and 9.3 L/day respectively with maximum COD removal efficiency of 91.2%. According to the obtained results, the hybrid system had 90% COD removal efficiency. Therefore, leachate COD loading could be effectively removed in this system

[Effect of simultaneous noise and carbon monoxide exposure on rabbits' auditory brain stem response]

Background: Noise induced hearing loss [NIHL] is one of the most important occupational diseases worldwide. NIHL has been found to be potentiated by some of air pollutants. Exposure to noise plus carbon monoxide is common in occupational and environmental settings. This study was performed to evaluate the effect of noise and carbon monoxide exposure simultaneously on rabbits' hearing system by Auditory Brain stem Response [ABR] assessment

Materials and Methods: In this experimental study, 24 male adult white rabbits were divided to four groups: control group, noise exposure group, noise plus carbon monoxide exposure group and carbon monoxide exposure group. Auditory Brain stem Responses of the four groups were determined: before exposure, 1 hour after exposure and 14 days after exposure by click and tone burst stimulus

Results: The latency mean time of V wave in the ABR test for the group exposed to noise plus carbon monoxide, 1 hour after exposure at 1, 2, 4 and 8 KHz frequency were respectively 5.43+/-0.08, 5.50+/-0.07, 5.71+/-0.07 and 5.75+/-0.07 millisecond. These values were significantly more than the same values in the other groups

Conclusion: NIHL may be potentiated by carbon monoxide in the simultaneous exposure. Thus, it seems occupational and environmental exposure to noise plus carbon monoxide may increases hearing loss risk

[ frequency of HBeAG and relation with serum level of aminotransferase in chronic hepatitis B]

Hepatitis B virus is the most frequent cause of acute and chronic hepatitis in the world. HBeAg should be assessed in the carriers of hepatitis B virus for the viral replication status. HBeAg+ patients with elevated aminotransferase should be treated with antiviral agents. Our aim was to determine the frequency of HBeAg positivity and the level of hepatic aminotransferase in the HBsAg+ population. In a case-control study in 2006, 144 infected patients with hepatitis B virus were examined for the presence of HBeAg and the level of serum aminotransferase by ELISA and biochemical test. The patients were selected from Imam Reza Hospital in Mashhad city. The frequencies of male and female in 144 hepatitis B infected patients were 94 and 50, respectively. They were between 2 to 85 years old with the mean of 37.4 +/- 2.3. Serum HBeAg was positive in 26 patients [18% of the total] with a mean serum AST level of 83 IU/L. HBeAg- group had a mean AST level of 56.2 IU/L. Statistical analysis showed a significant different in the mean serum levels of AST between two groups [p=0.007]. There was also significant difference in the levels of serum ALT between HBeAg+ [79 IU/L] and HBeAg- [73.7 IU/L] groups [P=0.018]. Based on our results the HBeAg positivity is associated with the increased level of liver enzymes. So the impact of HBeAg marker on serum level of hepatic aminotransferase in HBsAg+ patients should be assessed in future studies

Epidermal growth factor receptor gene in prostate cancer after radical prostatectomy

The aim of this study was to evaluate over expression of epidermal growth factor receptor [EGFR] gene in localized prostate cancers and determine its relation with clinical and pathological factors affecting the progression of the disease. In the tissue samples of the patients with prostate cancer undergoing radical prostatectomy, EGFR expression was evaluated by immunohistochemistry technique. Those with scores 2 and 3 were considered to be positive for the expression. The relation between gene expression and grade was evaluated by chi-square test. Of 100 tissue samples evaluated, 80 and 20 had Gleason score [GS] < 7 and >/= 7, respectively. Also, 68 and 32 had PSA level 10, respectively. A total of 59 samples were positive for EGFR expression, of whom, 46 had GS < 7 and 13 had GS > 7 [P-value = 0.39]. Forty patients had PSA < 10 and 19 had PSA > 10 [P-value = 0.5]. Fifty-nine percent of the patients with localized prostate cancer undergoing radical prostatectomy were EGFR positive. No significant relation was found between EGFR and grading [GS] or PSA

[Survey of relationship between ergonomic and environmental conditions of classrooms and pain sensation in students]

Inattention to ergonomic factors will influence the students' health and cause discomfort during their adulthood. The aim of this study was to determine the relationship between ergonomic and environmental conditions of classrooms and pain sensation in students. This cross-sectional study was carried out on 442 elementary students of Zahedan city in 2007. The type, weight and carrying method of satchel, body weight, sitting position and the pain sensation in different organs of body were assessed and registered in questionnaire. These variables were evaluated by using tape measure, scale and questionnaire. The data were analyzed by using descriptive and analytical [K2 test] statistics. This study showed that 30.68% of satchels' weight was greater than 10% of the students' weight. Among the students 59.3% were carrying their satchels on their back, 83.5% of students were using Backpacks. Pain sensation in different parts of body was described as shoulder pain [36.9%], knee pain [26.7%], and backache [20.8%]. There was no statistically significant relationship between the style of carrying satchel and the shoulder pain, wrist pain, and backache [p<0.05]. But there was a significant relationship between the type of satchel and wrist pain [p=0.039]. The training and considering to the ergonomic principals regarding the proper designing of classrooms, the type and weight of satchels are necessary

Effect of lamotrigine on prophylaxis of pediatric classic migraine

This study was conducted to evaluate the preventive effect of lamotringine on migraine aura and migraine attacks in children, afflicted with classic migraine. Conducted between October 2005 and April 2008 in the neurology clinic of Kashani hospital, Shahrekord, this study was a clinical trial, aimed at evaluating the prophylactic effects of Lamotringine administered to 21 children suffering from migraine with aura. Of the subjects, 52.4% of patients were female. The most common type of aura was visual [42.9%]. Following use of Lamotrigine, significant reductions were seen in the frequency [from 5 +/- 0.83 to 3.04 +/- 1.65] and in intensity [from 6. 33 +/- 1.08 to 3.66 +/- 1.1] of migraine aura [P= 0.002]. After 6 months of drug usage 66.6% of patients were improved. Lamotringine is effective in reducing the migraine aura and intensity of attacks in patients suffering from migraine with aura, and is hence beneficial for prophylactic therapy in children with classic migraine

Determining the effect of stress of threshold limit value of noise with shrill and bass frequencies on antioxidation and lipid peroxidation variations of liver tissue of rabbit

Background and Purpose: Noise, in high intensity, is one of the major physical stressors. The aim of this study was to determine the effect of stress of threshold limit value of noise with shrill and bass frequencies on antioxidation and lipid peroxidation variations of liver tissue of rabbit

Methods and Materials: This experimental study was carried out on 18 male white New Zealand rabbits at Tarbiat Modarres University in 2004. Rabbits were randomly divided into three groups: Control Group [unexposed to noise], Group 2 exposed to noise [85 dB SPL,< 250-3540Hz, 8 h/day, 96 h] and Group 3 exposed to noise [3540Hz-20kHz, 85 dB SPL, 8 h/day for 96h, 12 days]. The obtained data were analyzed in SPSS. One-way ANOVA and post hoc Tukey test were used for comparing means across the groups; differences at P<0.05 were considered statistically significant

Results: The findings indicated that Malondialdehyde [MDA] levels were 5.5, 5.54, and 5.71 in the groups 1, 2, and 3 respectively, and that the glutathione level was 0.131 g per micromol liver tissue across three groups. It was also found that the differences were not statistically significant [P=0<0.05]

Conclusion: According to the findings of the present study, despite limited variation in Malondialdehyde [MDA] levels induced by noise with 85dBA frequency, it does not induce significant changes in levels of Malondialdehyde [MDA] and glutathione in the liver tissue of rabbits

Stage I seminoma recurrences in patients admitted to radiotherapy clinic of Shohada hospital between 1991 and 2002

Currently, cancers are among the important and main problems of health system in Iran and around the world. In young men under 20 to 35 years of age, malignant masses of testis are the most common tumours. The main pathologic feature of these masses is germ cell tumour and about half of them are seminoma. Since seminoma is very prevalent in the forth decade, being affected with this tumour leads to losing many years of healthy life. In a cross sectional study, investigating 139 records of patients with testis tumour revealed 61 patients with stage-1 seminoma. Thirty three patients underwent para-aortic and unilateral pelvic irradiation [54%] while 28 patients only underwent para-aortic irradiation [46%]. The administered radiotherapy dosage varied between 25-40 Gy Mean age of the patients was 37.8 of whom the youngest was 15 and the oldest was 64 years of age. Only one recurrent patient was seen in this cohort who was in para-aortic group. There was no significant difference in recurrence rate between the two radiotherapy methods. [p= 0.7]. Considering fewer complications of para-aortic irradiation and the insignificant difference in the recurrence rate between the two methods of radiotherapy, para-aortic method could be more appropriate and acceptable in the treatment of testicular cancer

Changes in thyroid functional tests in breast Cancer patients under Tamoxifen therapy

Tamoxifen, a synthetic anti-estrogen agent, is administered as an adjuvant treatment in breast cancer. Since various studies have indicated that Tamoxifen can change some hormones and bound globolines, controversial results have been achieved using this medicine on Thyroid Functional Tests [TFT]. The present study was conducted to investigate the effects of Tamoxifen on TFT in women with breast cancer referred to oncology clinic in Imam Hossein hospital between 2001 and 2002. A quasi-experimental clinical trial study was performed on 23 women with breast cancer in a single blind basis [with no control group]. Patients were under Tamoxifen 20 mg P.O. daily and their serum TSH, free T4 and three Iodothyronine [T3] were assessed before treatment with Tamoxifen and after 3 months. Paired T test was used for statistical analysis. There was a significant difference in T3 before and after the treatment with Tamoxifen [p = 0.02], whereas no significant differences were seen in TSH [p = 0.095] and FT4 [p = 0.13]. This study showed that treatment with Tamoxifen in women suffering from breast cancer results in an increase in serum T3 but has no effect on serum TSH and FT4, therefore women under treatment with Tamoxifen remain euthyroid

[ benefical effects of raw momordica charantia fruit on some blood biochemical parameters in rats]

Momordica Charantia [MC] belongs to the cucurbitaceae family. MC is A plan that is widely used in traditional medicine as an antidiabetie agent.The aim of the present study was to evaluate the effect of the raw fruit of MC on some blood biochemical parameters in rats. Three groups of rats received a diet containing 1%, 2% and on MC [control group] respectively for a duration of two months. Blood samples were collected in the begining and at the end of the study. The sera were separated and used for determining of biochemical parameters including fasting blood suger [FBS]. glycated hemoglobin [HbAlc], cholesterol [cho], high density lipoproteins [HDL], low density lipoproteins [LDL], triglycerides [TG], urea [U] and creatininc [C]. The diet containing 1% and 2% MC decreased FBS significantly [p<0.002], and HbAlc [p<0.004] as compared to the control group. The 2% MC diet decreased Cho [p<0.001] and LDI [p<0.001] as compared to the control group. There was no significant change in the other factors. On the basis of the results obtained, it may be concluded that MC can effectively normalize glucose and lipid in patients. For better conclusion experimental human studies are recommended

[Evaluation of fragile X syndrome in patients with moderate mental retardation in Rafsanjan city]

Fragile X syndrome [FXS] is the most common cause of inherited mental retardation. Patients are identified with different levels of mental disabilities, elongated ears, prominent foreheads and chins, enlarged testes, large skull and obesity. This syndrom is generally associated with a break on X chromosome [Xq27.3], which can be observed in cultured chromosomes in specific culture media at metaphase stage. Prevalence rates of FXS in different ethnic groups have been estimated to be about one per 1500 in males and one per 2500 in females. The aim of this study was to determine FXS prevalence in moderate mental retarded students of Zohreh Shamsaei school in Rafsangan city. Fifty two students with moderate mental retardation [IQ=55-75] who were clinically suspicious to have FXS were screened for fragile X chromosome by using cytogenetic methods. Blood samples were collected and cultured in specific culture media. G-Banding method was used for karyotyping. Patients consisted of 37 males [71.2%] and 15 females [28.8%] with mean age of 12.7 years [ranged 7-17 years] and mean IQ 65.3 [ranged 55-74]. 8.1% of male students and 6.6% of female students were found to have fragile X site at Xq27.3 [in total 7.7%]. The frequencies of fragile X-positive cells in males and females were 8-52% and 12-27%, respectively. The frequency of fragile X positive cases found in this study is equal to that is reported by other investigators who studied the frequency of fragile X syndrome in preselected patients

5 year survival of breast cancer in Shohada-e- Tajrish and Jorjani Hospitals

Breast cancer is the most common cancer and the second most common cancer of cancer death in Iranian women after gastric carcinoma; although it is the second most common cancer in the western women after lung cancer. Its survival depends on multiple factors, which are very important to identify in order to understand natural history of the disease in Iran. In the present study, 154 patients with T1-T2-T3-NO-N1-MO breast cancer participated between March 1996 and March 1998 after surgery followed by adjuvant chemotherapy and/or radiation therapy and/or tamoxifen and were followed up for at least 5 years. Different factors might be effective on survival evaluation. Data was analyzed by SPSS, using chi-square and Kaplan Mayer method for survival analysis. 5 year survival was 76.5%.It decreased by lymph node involvement [72.9% versus 88.9%, p=0.034] and increased in estrogen receptor positive tumors [84.3% versus 62.5,p=0.024]. Left breast cancer patients survived more than right ones [87.5% versus 76.5%, p=0.004]. Tumor size, type of pathology, age, type of surgery [breast conservative surgery or mastectomy] progestrone receptors, HER-2 proto- oncogene and type of chemotherapy had no effect on survival. There is high survival by adjuvant therapy in Iran when breast cancers is detected at an early stage without lymph node involvement and receive appropriate therapy. The other factors should be studied more by future researches