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کاربرد نوع شرط:
- جایگاه : پژوهشی
- مجله: Iranian Journal of Medical Physics
- نوع مقاله: Journal Article
- کلمات کلیدی: Brachytherapy,Cervix Cancer,Radiation Induced Cancer
- چکیده:
- چکیده انگلیسی: Introduction: The present study aimed to measure the scatter and leakage dose received by out-of-field organs while delivering Radiotherapy (RT) treatment of cervical cancer. Moreover, this study estimated the risk of second cancer (SC). The doses to out-of-field organs were measured using a lithium fluoride (TLD 100) dosimeter while delivering External Beam Radiotherapy (EBRT) by 6 MV photon beam with Brachytherapy Boost (BB) treatment in the humanoid phantom.
Material and Methods: The excess absolute risk of SC for the stomach, colon, liver, lung, breast, and kidney, as well as excess relative risk for the thyroid, were estimated based on Biological Effects of Ionizing Radiation VII report.
Results: The out-of-field organ doses varied with respect to distance between organs. The colon (3DCRT-282.13 cGy and IMRT-381.24 cGy in 25 fractions) and kidney (70.65 cGy in 3 fractions) received the highest doses with EBRT and BB, respectively. For most of the aforementioned organs, the calculated dose was 0.2 Gy/fraction according to the treatment planning system. With the age at exposure (i.e., 30 years) as a reference, the highest LARs were associated with the colon (0.74%) and breast (2.76%) in 3DCRT plus BB and IMRT plus BB, respectively. The lifetime attributable risk of SC was also shown to decrease with increasing the age at exposure for all the organs.
Conclusion: Although all the evaluated out-of-field organs in this study showed some levels of risk, the risk was more frequently reported for the colon, stomach, and breast with IMRT technique than that in 3DCRT.- انتشار مقاله: 17-12-1397
- نویسندگان: Hemalatha A,ATHIYAMAN MAYILVAGANAN,Mary Joan,Arun Chougule,Kumar HS
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Medical Physics
- نوع مقاله: Journal Article
- کلمات کلیدی: Radiotherapy planning,Computer Assisted Radiotherapy,Radiotherapy Dosage
- چکیده:
- چکیده انگلیسی: Introduction: Computerized treatment planning is a rapidly evolving modality that depends on hardware and software efficiency. Despite ICRU recommendations suggesting 5% deviation in dose delivery the overall uncertainty shall be less than 3.5% as suggested by B.J. Minjnheer. J. In house spreadsheets are developed by the medical physicists to cross-verify the dose calculated by the Treatment Planning System (TPS). Materials and Methods: The monitor unit verification calculation (MUVC) verification was tested for pre-approved and executed treatment plans taken from the TPS. A total of 108 square fields and 120 multileaf-collimators (MLC) shaped fields for Head & Neck cancers, cervical and esophageal cancers were taken for evaluation. In house developed spreadsheet based on Microsoft Excel was developed. The dose calculation parameters such as Output Factor (O.F), Percentage Depth Dose (PDD) and off axis ratio (OAR) data were taken from the TPS. Results: The overall MU ratio fell within the range of 0.999 to 1.02 for square field geometries showing deviation of 1% between the TPS calculation and the spread sheet calculation. The MU ratios were 0.995 for Head & Neck plans & 1.012 for cervix plans with the standard deviation of 0.024 & 0.029 respectively. However we observed the mean MU ratio for Esophagus plan was 1.026 with the standard deviation of 0.040. Conclusion: The spreadsheet was tested for most of the routine treatment sites and geometries. It has good agreement with the Eclipse TPS version 13.8 for homogenous treatment sites such as head &and neck and carcinoma cervix.
- انتشار مقاله: 16-01-1396
- نویسندگان: Hemalatha Athiyaman,Athiyaman Mayilvaganan,Arun Chougule,Kumar HS
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Medical Physics
- نوع مقاله: Journal Article
- کلمات کلیدی: interpolation,Field Size,Linear Accelerator,Output factor
- چکیده:
- چکیده انگلیسی: Introduction: To estimate the accuracy levels of Lagrange, Newton backward interpolation, and linear interpolation methods in estimating the output factors for square fields used in linear accelerator for 6 MV photons at various depths.
Materials and Methods: Ionization measurements were carried out in radiation field analyzer in linear accelerator for 6 MV beams at the depths of 5 and 10 cm by 0.6 cc Farmer-type ionisation chamber. Dosimetry was performed by ion collection method with 0.5 cm2 interval for square fields from 4 × 4 cm2 to 40 × 40 cm2 field sizes. The measured output factor values for 10 square field sizes with equal interval were taken for interpolating the intermediate square field size values. The Lagrange and Newton backward methods were used for predicting the intermediate output factors.
Results: The percentage of deviation from the measured value was estimated for all the three methods. The calculated output factor values of the two proposed methods were compared with the standard linear interpolation method used in routine clinical practice. It was observed that the Lagrange and Newton backward methods were not significantly different from the measured value (P=0.77). The linear interpolation values were significantly different from the measured value (p <0.01).
Conclusion: It is recommended to use the Lagrange and Newton backward interpolation methods to estimate the intermediate output factors to increase accuracy in treatment delivery. The routine linear interpolation method can be applied only for small intervals. This proposed interpolation method is highly associated with the measured values in all the interval levels.- انتشار مقاله: 11-10-1395
- نویسندگان: Athiyaman Mayilvaganan,Hemalatha Athiyaman,Arun Chougule,Kumar HS
- مشاهده
- جایگاه : پژوهشی
- مجله: International Journal of Nano Dimension
- نوع مقاله: Journal Article
- کلمات کلیدی: Biofertilizer,plant growth,silver nanoparticles,Marine Endophytic Fungi,Mycosynthesis
- چکیده:
- چکیده انگلیسی: Seaweeds tend to have the property of acting as a biofertilizer for plants. Endophytes are organisms that are capable of mimicking and producing secondary metabolites similar to the host. In this report, silver nanoparticles (AgNPs) were synthesized from a marine endophytic fungus, Fusarium equiseti which was isolated from marine seaweed and identified using ITS sequencing. The synthesized Fusarium equiseti nanoparticle (FeNp) was characterized using UV Visible Spectrophotometer and field emission scanning electron microscope (FESEM). Efficacies of these nanoparticles to act as plant growth promoters were tested in laboratory conditions. Two different methods of administrations are nanopriming (NAP) and hydropriming (HYP), which were carried out with varying concentration of the FeNp (1ppm, 2.5ppm, 5ppm and 10 ppm). After comparing both the results, HYP method showed better results by favouring positive effects on wet weight, shoot length, root length, chlorophyll and carotenoid contents even at very low concentration (5ppm).The current results suggested that there is scope for these nanoparticles to be made into a biofertilizer after performing further toxicity studies under field conditions.
- انتشار مقاله: 27-03-1399
- نویسندگان: Mariam Adhila Haji Basheerudeen,Shariq Ahmed Mushtaq,Ranjani Soundhararajan,Senthil Kumar Nachimuthu,Hemalatha Srinivasan
- مشاهده
- جایگاه : پژوهشی
- مجله: International Journal of Nano Dimension
- نوع مقاله: Journal Article
- کلمات کلیدی: Antimicrobial effects,silver nanoparticles,SEM,TEM,EDAX,Endophytic Fungi
- چکیده:
- چکیده انگلیسی: The Myco silver nanoparticles (AgNPs) are synthesized through bio-reduction reaction of silver nitrate by cell-free filtrate of endophytic fungi, which act as both reducing and capping agent. The synthesis of silver nanoparticles (AgNPs) was confirmed through UV-VIS spectroscopy, Fourier Transform Infrared (FTIR), Transmission Electron Microscope (TEM), Scanning Electron Microscope (SEM). Energy Dispersive spectroscopy (EDAX) was used to study the structure, morphology, shape, and composition of synthesized nanoparticles. The efficacy of the silver nanoparticles (AgNPs) was tested against the pathogenic bacterial strains such as K. pneumonia, A. Baumannii, P. mirabilis, S. Typhimurium, P. aeruginosa and E. Coli. The myco silver nano particles treatment significantly reduced the growth of all the bacterial species tested in this study. The results suggested that myco nanoparticles can be utilized as an alternative to antibiotics or to break antimicrobial resistance.
- انتشار مقاله: 25-11-1396
- نویسندگان: Tahira Akther,Mohd Shahanbaj Khan,Hemalatha Srinivasan
- مشاهده
- جایگاه : پژوهشی
- مجله: Asian Pacific Journal of Cancer Prevention
- نوع مقاله: Journal Article
- کلمات کلیدی: Prognosis,Breast carcinoma, Cancer Stem Cells, Histopathology
- چکیده:
- چکیده انگلیسی: Background: CD133 is a commonly used cancer stem cell (CSC) marker in breast cancer. However, the association between CD133 expression, with clinicopathological features and prognosis in breast cancer, is poorly understood in the Indian subcontinent. This study was designed to explore the expression of CD 133 in breast carcinoma and to know its association between CD133 and clinicopathological characteristics. Methods: A total of fifty seven cases were included in the study. All the clinicopathological parameters were collected from Department of Pathology archives. Slides, blocks, clinical information, tumor size and axillary lymph node status were obtained from medical records and the pathology reports. Immunohistochemistry was done using CD 133 antibodies. Both Cytoplasmic and membranous staining was taken a positive. Scoring was done based on percentage of positive cells and intensity of staining. MS Excel, SPSS version 22 (IBM SPSS Statistics, Somers NY, USA) was used to analyze data.p value < 0.05 was considered as statistically significant. Results: Statistically significant association between the CD 133 expression and nodal metastasis, tumor stage and Nottingham prognostic index was analysed. There was no statistical correlation between CD 133 expression age, tumor grade and tumor size. The disease free survival showed the mean disease free survival of CD 133 positivity cases was 16months. And the patients who were negative for CD 133 expression had mean survival of 30 months. By the Kaplan Mayer graph it was evident that the more the CD 133 expression the lesser was the disease free survival of the patients. Conclusion: CD 133 expression was seen in 77.08% cases and was associated with tumor stage, lymph node metastasis, poor Nottingham prognostic index and worse disease free survival. An increasing trend of association was seen between CD 133 expression and Age, Tumor Size and Tumor grade.
- انتشار مقاله: 17-03-1399
- نویسندگان: Preeti Ashok Utnal,Hemalatha A,Sreeramulu PN,Manjunath GN
- مشاهده