Chemical composition and antibacterial activity from essential oil of Artemisia sieberi Besser subsp. Sieberi in North of Iran

The chemical composition and antibacterial effect of Artemisia siberi essential oil were studied in this research. The composition of essential oil from aerial parts was analyzed by GC/MS and its antibacterial effect were determined by disc diffusion method. Artemisia ketone (48.5%), 1, 8-cineole (19.7%), selin-11-en-4-a-ol (4.6%) and lavandulon (2.8%) were the major constituents of this herbal medicine. Inhibitory zone against Pseudomonas aeroginosa, Staphylococcus aureus and Escherichia coli around discs contained 100 mg mL-1 of Artemisia siberi essential oil were 18, 13 and 12 mm, respectively. Further studies for the determination of and Pseudomonas infection in animal model are suggested. © 2007 Asian Network for Scientific Information

Interaction between random heterogeneously charged surfaces in an electrolyte solution

We study, using Monte Carlo simulations, the interaction between infinite heterogeneously charged surfaces inside an electrolyte solution. The surfaces are overall neutral with quenched charged domains. An average over the quenched disorder is performed to obtain the net force. We find that the interaction between the surfaces is repulsive at short distances and is attractive for larger separations

A symmetry classification for a class of (2+1)-nonlinear wave equation

In this paper, a symmetry classification of a $(2+1)$-nonlinear wave equation $u_{tt}-f(u)(u_{xx}+u_{yy})=0$ where $f(u)$ is a smooth function on $u$, using Lie group method, is given. The basic infinitesimal method for calculating symmetry groups is presented, and used to determine the general symmetry group of this $(2+1)$-nonlinear wave equation

High frequency of the IL-2 -330 T/HLA-DRB1*1501 haplotype in patients with multiple sclerosis

We have evaluated the role of the HLA-DRB1*1501 allele and the IL-2 -330 T/G polymorphism and their interaction in susceptibility to multiple sclerosis on 360 patients and 426 matched healthy individuals. We used the SSP-PCR method to determine the alleles. Fisher's exact test was used to analyses. We observed a significant increase in the T allele at IL-2 -330 position in patients (OR = 1.34, P<0.05), and the T/T and T/G genotypes were more frequent among patients than controls. The HLA-DRB1*1501 allele was overrepresented in patients as compared to the control group (OR = 1.7, P=0.0006). The two-locus analysis of the interaction between the IL-2 promoter polymorphism and the HLA-DRB1 allele showed that the HLA-DRB1*1501/T haplotype was more frequent in patients than controls (OR=16, P<0.0001). Our findings support previous findings about the role of the HLA-DRB1*1501 allele in susceptibility to MS. This work also provides new findings about the importance of gene-gene interactions in the development of MS. © 2010 Elsevier Inc

Dosimetric Comparison of Four Different Techniques for Supraclavicular Irradiation in 3D-conformal Radiotherapy of Breast Cancer

This study aimed to compare and evaluated the dosimetric characteristics of esophagus, spinal cord, carotid artery, lungs, and brachial plexus in patients with breast cancer undergoing four various techniques of supraclavicular irradiation. By keeping unchanged the breast tangential radiotherapy fields, four different treatment field arrangements were created to irradiate the supraclavicular region as follows: (1) four field (4F; 1 anterior-posterior and 1 posterior-anterior), (2) six field (6F; 2 anterior-posterior and 2 posterior-anterior), (3) five field-1 (5F-1; 2 anterior-posterior and 1 posterior-anterior), and (4) five field-2 (5F-2; 1 anterior-posterior and 2 posterior-anterior). Then, the dosimetric parameters for the above-mentioned organs were evaluated. The mean dose (Dmean) of the esophagus had significant difference between 6F and 5F-2 techniques. For the spinal cord, the Dmean dosimetric parameter demonstrated significant difference between the 4F and 6F techniques, and between the 4F and 5F-1 techniques, with lower values for the 4F technique. There was no significant difference between the different irradiation techniques in all the dosimetric parameters for the carotid artery. The Dmean of the left lung significantly differed between the 4F and 5F-2 techniques, with lower values for the 5F-2 technique. Furthermore, the V20Gy dosimetric parameter had significant difference between the 4F and 6F, and also 4F and 5F-2, techniques with lower values for 5F-2. The maximum dose (Dmax) of the brachial plexus showed significant difference between the two techniques of 5F. The V45Gy dosimetric parameter of the brachial plexus revealed significant difference between the 4F and 6F techniques, and also between the 4F and 5F-1 techniques, with lower values for 5F-1. In general, these techniques had similar dosimetric results, with little differences. The dosimetric parameters for the esophagus and lung showed better results with the 5F-2 technique in comparison with other techniques. Dosimetric results for the brachial plexus and spinal cord improved with the 5F-1 and 4F techniques, respectively, against other techniques. Dose distribution for the carotid artery did not differ in the four irradiation techniques

2D Dose Reconstruction by Artificial Neural Network for Pretreatment Verification of IMRT Fields

The use of intensity-modulated radiation therapy (IMRT) is developing rapidly in clinical routines. Because of the high complexity and uniqueness of IMRT treatment plans, patient-specific pretreatment quality assurance is generally considered a necessary prerequisite for patient treatment. In this work, we proposed a modified methodology of electronic portal imaging device (EPID)�based dose validation for pretreatment verification of IMRT fields by applying artificial neural networks (ANNs). The ANN must be trained and validated before use for pretreatment dose verification. For this purpose, 20 EPID fluence maps of IMRT prostate anterior-posterior fields were used as an input for ANN (feed forward type) and a dose map of those fluence maps that were predicted by treatment planning system as an output for ANN. After the training and validation of the neural network, the analysis of 10 IMRT prostate anterior-posterior fields showed excellent agreement between ANN output and dose map predicted by the treatment planning system. The average overall fields pass rate was 96.0 ± 0.1 with 3 mm/3 criteria. The results indicated that the ANN can be used as a low-cost, fast, and powerful tool for pretreatment dose verification, based on an EPID fluence map. © 201

Attenuation correction in myocardial perfusion SPECT using sequential transmission - Emission scanning with 99mTc

Introduction: Nowadays, Imaging of the myocardial perfusion (MPI) using the single photon emission tomography (SPET) in the diagnosis of coronary artery disease, especially myocardial ischemia, is of great importance. In contrast to the coronary artery angiography, MPI is non-invasive, less expensive and more physiological. Unfortunately, this image is affected by the some artifacts. These artifacts lead to decrease image diagnostic accuracy and increase false positive cases. One of the most important effective artifacts is due to attenuation. These attenuation artifacts are caused by the left breast tissue in women, diaphragm in men and the chest wall in both sexes. Because of the inherent non- uniform attenuation map in the thorax region, this problem is very complex. Methods: The aim of this study is to correct attenuation artifact with a simple method that is available and very easy to use. In this study we used transmission scanning by 99mTc in the sequential views and an attenuation map was created. After attenuation correction of the original images with attenuation map, non corrected and corrected images were compared with angiography results to apply attenuation correction based on functional findings. Results: Results show that new artifacts are created and experiences of physicians in the impression of the images is critical. Finally, the sensitivity of images increased from 86.20 to 96.42, the specificity decreased from 85.71 to 54.54 and the diagnostic accuracy decreased from 86 to 78. Conclusion: Attenuation correction can produce new artifacts, which can influence the way scans are interpreted. It seems that attenuation correction of the images, need special experience. Lack of enough experience in attenuation correction techniques, can comprise the diagnostic accuracy of images

The use of EBT3 film and Delta4 for the dosimetric verification of EclipseTM treatment planning system in a heterogeneous chest phantom: An IMRT technique

Background: This study aimed to evaluate the dose calculation accuracy of EclipseTM treatment planning system (TPS) in a heterogeneous chest phantom with the intensity modulated radiotherapy (IMRT) technique using EBT3 film and Delta4. Materials and Methods: Two IMRT plans (A and B) were prepared for radiotherapy of the heterogeneous chest phantom. Plan A was between the left lung and the surrounding soft tissue and plan B was carried out on the soft tissue. EBT3 film and Delta4 were used for dose measurement in the phantom. EclipseTM TPS was also used for dose calculation. Finally, the gamma index values of the TPS with film and TPS with Delta4 were obtained. A 95 passing rate of gamma index with the passing criterion of 3mm/3 and a dose threshold of 20 as the standard criterion was considered in this study. Furthermore, the passing rates of gamma indices of the film and Delta4 were compared with each other via Bland-Altman analysis. Results: The mean passing rate of gamma index with standard passing criterion between the TPS calculations and film measurements was 96.95±0.22, while it was equal to 97.7±0.56 and 98.45±0.21 between the TPS calculations and 2D and 3D Delta4 measurements, respectively. Additionally, the differences between the passing rates of gamma indices of the film and Delta4 were less than 5. Conclusion: The findings demonstrate that the accuracy of dose calculations of EclipseTM TPS in a heterogeneous chest phantom with the IMRT technique is within the standard passing criterion. Furthermore, it can be concluded that there is a good agreement between the film and Delta4, as IMRT QA devices. © 2019 Novin Medical Radiation Institute. All rights reserved