Association of TIM-1 5383-5397ins/del and TIM-3 -1541C>T polymorphisms with multiple sclerosis in Isfahan population.

Multiple sclerosis (MS) is an organ-specific autoimmune disease in central nervous system, affecting about 2.5 million people around the world. Probable involvement of two newly identified immunoregulator molecules, TIM-1 and TIM-3, has been reported in autoimmune diseases. In this study, for the first time, the association of TIM-1 5383-5397ins/del and TIM-3 -1541C>T polymorphisms with MS in an Iranian population was considered. The results of our study showed that there is no significant association between TIM-1 5383-5397ins/del and MS (P = 0.38); however, the frequency of CT genotype of TIM-3 -1541C>T in patient group was significantly higher than the control group, and there was a significant association between CT genotype and MS (P = 0.009, OR = 4.08).

Breast dosimetry in transverse and longitudinal field MRI-Linac radiotherapy systems.

PURPOSE: In the framework of developing the integration of a MRI-Linac system, configurations of MRI-Linac units were simulated in order to improve the dose distribution in tangential breast radiotherapy using transverse and longitudinal magnetic field geometries of Lorentz force for both medial and lateral tangential fields. METHODS: In this work, the geant4 Monte Carlo (MC) code was utilized to compare dose distributions in breast radiotherapy for Linac-MR systems in the transverse and longitudinal geometries within humanoid phantoms across a range of magnetic field strengths of 0.5 and 1.5 T. The dose increment due to scattering from the coils was investigated for both geometries as well. Computed tomography images of two patients were used for MC simulations. One patient had intact breast while the other was mastectomized. In the simulations, planning and methods of chest wall irradiation were similar to the actual clinical planning. RESULTS: In a longitudinal geometry, the magnetic field is shown to restrict the lateral spread of secondary electrons to the lung, heart, and contralateral organs, which reduced the mean dose of the ipsilateral lung and heart by means of 17.2% and 6% at 1.5 T, respectively. The transverse configuration exhibits a significant increase in tissue interface effects, which increased dose buildup in the entrance regions of the lateral and medial tangent beams to the planning target volume (PTV) and improved dose homogeneity within the PTV. The improved relative average homogeneity index for two patients to the PTV at magnetic field strength of 1.5 T with respect to no magnetic field case evaluated was 11.79% and 34.45% in the LRBP and TRBP geometries, respectively. In both geometries, the simulations show significant mean dose reductions in the contralateral breast and chest wall skin, respectively, by a mean of 16.6% and 24.9% at 0.5 T and 17.2% and 28.1% at 1.5 T in the transverse geometry, and 10.56% and 14.6% at 0.5 T and 11.3% and 16.3% at 1.5 T in the longitudinal geometry. Considering the scattered photons which reflected from the coils, the average relative dose of each voxel is slightly increased by 0.53% and 0.32% in the LRBP and TRBP geometries, respectively. CONCLUSIONS: Orienting the B0 magnetic field parallel to the photon beam axis, LRBP geometry, tends to restrict the radial spread of secondary electrons which resulted in dose reduction to the lung. Dosimetry issues observed in both Linac-MR geometries, such as changes to the lateral dose distribution, significantly exhibited dose reduction in the contralateral organs on a representative breast plan. Further, the results show sharper edge dose volume histogram curves at 1.5 T for both geometries, especially in the LRBP configuration.

Improvement of dose distribution in breast radiotherapy using a reversible transverse magnetic field Linac-MR unit.

PURPOSE: To investigate the improvement in dose distribution in tangential breast radiotherapy using a reversible transverse magnetic field that maintains the same direction of Lorentz force between two fields. The investigation has a potential application in future Linac-MR units. METHODS: Computed tomography images of four patients and magnetic fields of 0.25-1.5 Tesla (T) were used for Monte Carlo simulation. Two patients had intact breast while the other two had mastectomy. Simulations of planning and chest wall irradiation were similar to the actual clinical process. The direction of superior-inferior magnetic field for the medial treatment beam was reversed for the lateral beam. RESULTS: For the ipsilateral lung and heart mean doses were reduced by a mean (range) of 45.8% (27.6%-58.6%) and 26.0% (20.2%-38.9%), respectively, depending on various treatment plan setups. The mean V20 for ipsilateral lung was reduced by 55.0% (43.6%-77.3%). In addition acceptable results were shown after simulation of 0.25 T magnetic field demonstrated in dose-volume reductions of the heart, ipsilateral lung, and noninvolved skin. CONCLUSIONS: Applying a reversible magnetic field during breast radiotherapy, not only reduces the dose to the lung and heart but also produces a sharp drop dose volume histogram for planning target volume, because of bending of the path of secondary charged particles toward the chest wall by the Lorentz force. The simulations have shown that use of the magnetic field at 1.5 T is not feasible for clinical applications due to the increase of ipsilateral chest wall skin dose in comparison to the conventional planning while 0.25 T is suitable for all patients due to dose reduction to the chest wall skin.

WIH-based IEEE 802.11 ECG monitoring implementation.

New wireless technologies make possible the implementation of high level integration wireless devices which allow the replacement of traditional large wired monitoring devices. It offers new functionalities to physicians and will reduce the costs. Among these functionalities, biomedical signals can be sent to other devices (PDA, PC . . . ) or processing centers, without restricting the patients' mobility. This article discusses the WIH (Ward-In-Hand) structure and the software required for its implementation before an operational example is presented with its results. The aim of this project is the development and implementation of a reduced size electrocardiograph based on IEEE 802.11 with high speed and more accuracy, which allows wireless monitoring of patients, and the insertion of the information into the Wi-Fi hospital networks.