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کاربرد نوع شرط:
- جایگاه : پژوهشی
- مجله: Iranian Journal of Medical Physics
- نوع مقاله: Journal Article
- کلمات کلیدی: Serum,survival rate,Radiation Effects,Adaptive response
- چکیده:
- چکیده انگلیسی: Introduction: Adaptive response is one of the important concepts in radiobiology. The present report aimed to transfer the radio-adaptation via serum.
Material and Methods: In total, 50 male adult Wistar rats were randomly divided into 6 groups, including control, serum control, low-dose (100cGy), low-dose/lethal, serum/lethal, and lethal (8Gy). Exposure was carried out by a linear accelerator (Elekta Synergy® Platform) with a 40×40cm field size. The animals were monitored in terms of the endpoints of the survival rate, and at the first stage, the rats were exposed to the low doses of radiation. Subsequently, the serum was injected intraperitoneally under sterile conditions 6 h after low-dose exposure. The Kaplan Meier Survival Curve was used to evaluate the survival rate (p <0.05).
Results: There was a significant difference among different groups regarding the survival rates. Moreover, a statistically significant difference was observed between low-dose/lethal and low-dose/serum, low-dose/lethal and lethal, and low-dose/serum and lethal (P=0.001). Similarly, there was a statistically significant difference between the control and experimental groups regarding the survival rates (P=0.001).
Conclusion: To the best of our knowledge, this method can lead to immunological responses or unknown mechanisms that result in the increased survival adaptive response to subsequent high-dose radiation.- انتشار مقاله: 02-02-1398
- نویسندگان: Ehsan Khodamoradi,Rasool Azmoonfar,Mohammad Mohammadi,Amir Kiani,Abbas Haghparast,Nasrin Sharafi,Loghman Diojan
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Medical Physics
- نوع مقاله: Journal Article
- کلمات کلیدی: Breast cancer,Treatment Planning,High-Energy X-Ray,Field-In-Field Technique,TWB Plan
- چکیده:
- چکیده انگلیسی: Introduction: In this study, dose distribution of the chest wall in post-mastectomy breast cancer patients was evaluated and compared in the tangential wedged beam (TWB) and field-in-field (FIF) plans.
Materials and Methods: Thirty-six patients with left-sided breast cancer were enrolled in this study. The FIF and TWB plans were generated for each patient to compare dosimetric parameters of the chest wall. The maximum dose (Dmax), homogeneity index (HI), conformity index (CI), and uniformity index (UI) were defined and used for comparison of the dosimetric parameters of the planning target volume (PTV) in both FIF and TWB plans. The percentage of volumes receiving at least 10, 20, 30, and 40 Gy of the left lung and 5, 10, 20, 25 and 30 Gy of the heart were used to compare the dosimetric results of the organs at risk. Statistical analysis was performed using SPSS, version 20.
Results: The FIF plan had significantly lower HI (P=0.000) than the TWB plan, indicating that the FIF plan was better than the TWB plan in PTV. The V40lung (15.36±4.35 vs. 18.37±4.42) and V30heart (8.15±3.75 vs. 10.94±3.94; P=0.000) were significantly lower in the FIF plan than in the TWB plan. In addition, the monitor unit (MU) was significantly lower in the FIF plan than in the TWB plan (227.76 vs. 323.59; P=0.000).
Conclusion: The FIF plan significantly reduced the dose volume of the left lung and heart in post-mastectomy radiotherapy compared to the TWB plan. Therefore, the FIF plan is recommended for this purpose.- انتشار مقاله: 29-01-1396
- نویسندگان: Mehran Yarahmadi,Bahar Faramarzi,Abbas Haghparast,Zeinab Saalehi
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Medical Physics
- نوع مقاله: Journal Article
- کلمات کلیدی: optimization,High-Intensity Focused Ultrasound Ablation,Nonlinearity KZK Equation,Thermal Dose
- چکیده:
- چکیده انگلیسی: Introduction
High intensity focused ultrasound (HIFU) is considered a noninvasive and effective technique for tumor ablation. Frequency and acoustic power are the most effective parameters for temperature distribution and the extent of tissue damage. The aim of this study was to optimize the operating transducer parameters such as frequency and input power in order to acquire suitable temperature and thermal dose distribution in the course of a numerical assessment.
Materials and Methods
To model the sound propagation, the Khokhlov-Zabolotskava-Kuznetsov (KZK) nonlinear wave equation was used and simulation was carried out using MATLAB HIFU toolbox. Bioheat equation was applied to calculate the transient temperature in the liver tissue. Frequency ranges of 2, 3, 4, and 5 MHz and power levels of 50 and 100 W were applied using an extracorporeal transducer.
Results
Using a frequency of 2 MHz, the maximum temperatures reached 53°C and 90°C in the focal point for power levels of 50 W and 100 W, respectively. With the same powers and using a frequency of 3 MHz, the temperature reached to 71°C and 170°C, respectively. In addition, for these power levels at the frequency of 4 MHz, the temperature reached to 72°C and 145°C, respectively. However, at the 5 MHz frequency, the temperature in the focal spot was either 57°C or 79°C.
Conclusion
Use of frequency of 2 MHz and power of 100 W led to higher thermal dose distribution, and subsequently, reduction of the treatment duration and complications at the same exposure time in ablation of large tumors.
- انتشار مقاله: 06-07-1395
- نویسندگان: Somayeh Gharloghi,Mehrdad Gholami,Abbas Haghparast,Vahab Dehlaghi
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Basic Medical Sciences
- نوع مقاله: Journal Article
- کلمات کلیدی: Rat,Memory,Gallic acid,Traumatic brain injury,Long-term potentiation,Brain inflammation
- چکیده:
- چکیده انگلیسی: Objective(s): Traumatic brain injury (TBI) is one of the main causes of intellectual and cognitive disabilities. Clinically, it is essential to limit the development of cognitive impairment after TBI. In the present study, the neuroprotective effects of gallic acid (GA) on neurological score, memory, long-term potentiation (LTP) from hippocampal dentate gyrus (hDG), brain lipid peroxidation and cytokines after TBI were evaluated.
Materials and Methods: Seventy-two adult male Wistar rats divided randomly into three groups with 24 in each: Veh + Sham, Veh + TBI and GA + TBI (GA; 100 mg/kg, PO for 7 days before TBI induction). Brain injury was made by Marmarou’s method. Briefly, a 200 g weight was fallen down from a 2 m height through a free-falling tube onto the head of anesthetized animal.
Results: Veterinary coma scores (VCS), memory and recorded hDG -LTP significantly reduced in Veh + TBI group at 1 and 24 hr after TBI when compared to Veh + Sham (P<0.001), respectively, while brain tissue content of interleukin-1β (IL-1β), IL-6, tumor necrosis factor-α (TNF-α) and malondialdehyde (MDA) were increased significantly (P<0.001). Pretreatment of TBI rats with GA improved clinical signs, memory and hDG-LTP significantly (P<0.001) compared to Veh + TBI group, while brain tissue content of IL-1β, IL-6, TNF-α and MDA were decreased significantly (P<0.001).
Conclusion: Our results propose that GA has neuroprotective effect on memory and LTP impairment due to TBI through decrement of brain lipid peroxidation and cerebral pro-inflammatory cytokines.- انتشار مقاله: 17-11-1396
- نویسندگان: Mohammad Ali Mirshekar,Alireza Sarkaki,Yaghoob Farbood,Mohammad Kazem Gharib Naseri,Mohammad Badavi,Mohamad Taghi Mansouri,Abbas Haghparast
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Basic Medical Sciences
- نوع مقاله: Journal Article
- کلمات کلیدی: Rat,Memory,Gallic acid,Traumatic brain injury,Long-term potentiation,Brain inflammation
- چکیده:
- چکیده انگلیسی: Objective(s): Traumatic brain injury (TBI) is one of the main causes of intellectual and cognitive disabilities. Clinically, it is essential to limit the development of cognitive impairment after TBI. In the present study, the neuroprotective effects of gallic acid (GA) on neurological score, memory, long-term potentiation (LTP) from hippocampal dentate gyrus (hDG), brain lipid peroxidation and cytokines after TBI were evaluated.
Materials and Methods: Seventy-two adult male Wistar rats divided randomly into three groups with 24 in each: Veh + Sham, Veh + TBI and GA + TBI (GA; 100 mg/kg, PO for 7 days before TBI induction). Brain injury was made by Marmarou’s method. Briefly, a 200 g weight was fallen down from a 2 m height through a free-falling tube onto the head of anesthetized animal.
Results: Veterinary coma scores (VCS), memory and recorded hDG -LTP significantly reduced in Veh + TBI group at 1 and 24 hr after TBI when compared to Veh + Sham (P<0.001), respectively, while brain tissue content of interleukin-1β (IL-1β), IL-6, tumor necrosis factor-α (TNF-α) and malondialdehyde (MDA) were increased significantly (P<0.001). Pretreatment of TBI rats with GA improved clinical signs, memory and hDG-LTP significantly (P<0.001) compared to Veh + TBI group, while brain tissue content of IL-1β, IL-6, TNF-α and MDA were decreased significantly (P<0.001).
Conclusion: Our results propose that GA has neuroprotective effect on memory and LTP impairment due to TBI through decrement of brain lipid peroxidation and cerebral pro-inflammatory cytokines.- انتشار مقاله: 17-11-1396
- نویسندگان: Mohammad Ali Mirshekar,Alireza Sarkaki,Yaghoob Farbood,Mohammad Kazem Gharib Naseri,Mohammad Badavi,Mohamad Taghi Mansouri,Abbas Haghparast
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Basic Medical Sciences
- نوع مقاله: Journal Article
- کلمات کلیدی: Amygdala,morphine dependence,naloxone,Nitric oxide
- چکیده:
- چکیده انگلیسی: Objective(s) Single injection of naloxone, a selective antagonist of morphine, prior to the drug conditioning testing was used to investigate on morphine dependence. Materials and Methods Conditioning to morphine (2.5-10 mg/kg, s.c.) was established in adult male Wistar rats (weighing 200-250 g) using an unbiased procedure. Nitric oxide agents were microinjected into the central amygdala prior to naloxone-paired place conditioning testing. Results The results showed that morphine produced a significant dose-dependent place preference in animals. Naloxone (0.1-0.4 mg/kg, i.p.) injections pre-testing of the response to morphine (7.5 mg/kg, s.c.) caused a significant aversion at the higher doses (0.4 mg/kg, i.p.). This response was reversed by microinjection of L-arginine (0.3-3 μg/rat, intra-central amygdala) prior to naloxone on the day of the testing. The response to L-arginine was blocked by pre-injection of NG-nitro-L-arginine methyl ester (L-NAME) (intra-central amygdala). Conclusion A single injection of naloxone on the test day of morphine place conditioning may simply reveal the occurrence of morphine dependence in rats, and that the nitric oxide in the central amygdala most likely plays a key role in this phenomenon.
- انتشار مقاله: 30-06-1394
- نویسندگان: Mahnaz Rahimpour,Manizheh Karami,Sara Karimi,Abbas Haghparast,Mohammad Reza Jalali,Farzaneh Sabouni
- مشاهده
- جایگاه : پژوهشی
- مجله: International Journal of Hospital Research
- نوع مقاله: Journal Article
- کلمات کلیدی: Multiple Sclerosis (MS),Paranasal sinuses,Magnetic resonance imaging (MRI),Central nervous system (CNS)
- چکیده:
- چکیده انگلیسی: Background and Objectives: Multiple sclerosis (MS) is the most common demyelinating disease of the central nervous system with more than 5.2 million people across the world being afflicted with. Magnetic Resonance Imaging (MRI) is a valuable tool in the diagnosis of MS. This study surveys the results of MRI of the central nervous system and paranasal sinuses in the sample of MS patients in Kermanshah Province, Iran.
Methods: The clinical records of a total of 294 patients admitted to the Neurology Ward of Farabi Hospital of Kermanshah City (Western Iran) between 2004 and 2014 and diagnosed to be afflicted with MS were surveyed. The data were collected using a checklist prepared based on the McDonald Wibers standard criteria. The checklist consisted of 37 items, related to the MRI data of the CNS and paranasal sinuses of MS patients. The data were collected in four domains, including the most common early clinical signs of the patient, distribution of lesions, affliction with sinusitis, and demographic characteristics. The collected data were summarized using descriptive statistical methods.
Findings: MRI identified MS plaques in 94.90% of the patients. Female, Married, housekeeping, and undergraduate patients and the patients with 21-40 years of age had the highest frequency among the MS patients (59.5%, 50.2%, 70.6%, 42%, and 72%). Hands and feet anaesthesis was the most frequently seen early signs (63.80%), followed by visual impairment (42.3%) and ataxia (12.6%). The most frequently involved anatomic site was the white matter surrounding the ventricles (77.50%), followed by centrum semiovale (75.4%), and corpus callosum (17.1%). We also found that 16% of the patients afflicted with MS had sinusitis, with the most frequent anatomical sites afflicted in them being sphenoid sinuses (63.8%).
Conclusions: Our study provided further evidence that the MRI is an accurate and reliable method for diagnosing MS. No gross differences in the frequency of MS disease among age, sex, and lesion pattern groups compared to other studies were identified. Observing sinusitis in patients afflicted with MS is suggestive of their random association.- انتشار مقاله: 24-08-1394
- نویسندگان: Fatemeh Amiri,Maryam Pourkaveh,Abbas Haghparast,Amir Hossein Hashemian
- مشاهده
- جایگاه : پژوهشی
- مجله: International Journal of Advanced Biological and Biomedical Research
- نوع مقاله: Journal Article
- کلمات کلیدی: Medical linear accelerator,Photon field size,Neutron contamination,CR-39 dosimeter
- چکیده:
- چکیده انگلیسی: Objective: Using Megavoltage photons generated by medical linear accelerator is a common modality for the treatment of malignant. The crucial problem for using photon beams >8MV is the photoneutron yields that increase the risk of secondary cancer that treated with high-energy photon beams. The contaminated neutrons produced in different components of the accelerator head and rely on many parameters. The purpose of this study was to determine the effect of field size on the neutron dose equivalent in center and far from it at the Elekta Sl 75/25 18 MV linear accelerator. Methods: Neutron dosimetry was carried out with CR-39 films with using of chemical etching technique. The measurement was done at isocenter, 25 cm and 50 cm far from it at 100 cm SSD for squared field with 5 up to 30 cm side. Results: The results revealed that the neutron dose equivalent increased with increasing field sizes especially for 5*5 cm2 field size. It was decreased with increasing distance from the isocenter.Conclusion:The effect of field size on neutron contamination depend on amount of field aperture where in small field size 5×5 cm2 less variation need for significant change but for larger field size 10×10 cm2 this variation must be larger. The contaminated neutron outside photon field is independent of field size.
- انتشار مقاله: 12-02-1394
- نویسندگان: Mahdi Jahangiri,Payman Hejazi,Seyed Mehdi Hashemi,Abbass Haghparast,Bardia Hajizadeh
- مشاهده