Measurement of the photon and thermal neutron doses of contralateral breast surface in breast cancer radiotherapy

Introduction and purpose:During the radiation therapy of tumoral breast, the contralateral breast (CB) will receive scattered doses. In the present study, the photon and thermal neutron dose values received by CB surface during breast cancer radiation therapy were measured.Materials and methods:The right breast region of RANDO phantom was considered as CB, and the measurements of photon and thermal neutron dose values were carried out on this region surface. The phantom was irradiated with 18 MV photon beams, and the dose values were measured with thermoluminescent dosimeter (TLD-600 and TLD-700) chips for 11 � 13, 11 � 17 and 11 � 21 cm2 field sizes in the presence of physical and dynamic wedges.Results:The total dose values (photon + thermal neutron) received by the CB surface in the presence of physical wedge were 12·06, 15·75 and 33·40 of the prescribed dose, respectively, for 11 � 13, 11 � 17 and 11 � 21 cm2 field sizes. The corresponding dose values for dynamic wedge were 9·18, 12·92 and 29·26 of the prescribed dose, respectively. Moreover, the results showed that treatment field size and wedge type affect the received photon and thermal neutron doses at CB surface.Conclusion:According to our results, the total dose values received at CB surface during breast cancer radiotherapy with high-energy photon beams are remarkable. In addition, the dose values received at CB surface when using a physical wedge were greater than when using a dynamic wedge, especially for medial tangential fields. © Cambridge University Press 2019

Ecological species groups in the rural heritage museum of Guilan Province, Iran

The objective of this research was to identify and describe the different Ecological Species Groups (vegetation types) present in the Rural Heritage Museum of Guilan. The study area was approximately 260 ha, which is located in the Saravan Forest Park in Guilan province, north of Iran. Sampling procedure was performed with a systematic random technique. A total of 89 plots were sampled. Classification of vegetation carried out using the Two Way Indicator Species Analysis (TWINSPAN) method showed that there were five ecological species groups in three layers; three groups in the shrub layer, nine groups in the herb layer and six ecological species groups in the regeneration layer. The results suggest improved protection and management of this area and that it can be proposed as a protected area on the basis of the numerous important species. The information obtained from the current study about this forest is useful for the design and management of this site because of its aesthetic values

The sequential twinning-transformation induced plasticity effects in a thermomechanically processed high Mn austenitic steel

Different initial microstructures with various bimodal grain size distributions (BGSD) were produced in a high Mn austenitic steel through applying a predetermined set of thermomechanical processing cycles. The corresponding room temperature mechanical properties and the related strain hardening behaviors were assessed using tensile testing method. The results indicated that in the microstructure with high grain size bimodality, the length and amplitude of rapid hardening region was well higher than the others. This was attributed to its higher capability to a'-martensite formation. In addition, the threshold strain to initiate martensitic transformation was shifted to the lower one in the microstructure with higher bimodal grain size distribution. The latter was related to the lower arisen back stresses in the interior regions of the coarser grains. Furthermore, different transformation paths were identified as the BGSD changed. The austenite could directly transform to a'-martensite (¿a') in the microstructure with lower BGSD; in this case the a'-martensite mainly appeared at the intersections of deformation twins. In contrast, in microstructures with higher BGSD, the nucleation occurred at the intersections of e-martensite platelets. The co-existence of these transformation paths provided an extended transformation induced plasticity effect ending to a higher elongation to fracture in the course of deformation. In order to summarize the contribution of various strain hardening mechanisms, a deformation map was also constructed. Accordingly, the enhanced ductility/strength properties were attributed to the sequential operation of extended transformation induced plasticity and twinning induced plasticity effects.Peer ReviewedPostprint (author's final draft

European mtDNA Variants Are Associated With Differential Responses to Cisplatin, an Anticancer Drug: Implications for Drug Resistance and Side Effects.

Background: Cisplatin, a powerful antitumor agent, causes formation of DNA adducts, and activation of apoptotic pathways. Presently, cisplatin resistance develops in up to 70% of patients but the underlying molecular mechanism(s) are unclear and there are no markers to determine which patients will become resistant. Mitochondria play a significant role not only in energy metabolism but also retrograde signaling (mitochondria to nucleus) that modulates inflammation, complement, and apoptosis pathways. Maternally inherited mitochondrial (mt) DNA can be classified into haplogroups representing different ethnic populations that have diverse susceptibilities to diseases and medications. Methods: Transmitochondrial cybrids, where all cell lines possess identical nuclear genomes but either the H (Southern European) or J (Northern European) mtDNA haplogroups, were treated with cisplatin and analyzed for differential responses related to viability, oxidative stress, and expression levels of genes associated with cancer, cisplatin-induced nephrotoxicity and resistance, apoptosis and signaling pathways. Results: The cisplatin-treated-J cybrids showed greater loss of cell viability along with lower levels of reactive oxygen species and mitochondrial membrane potential compared to cisplatin-treated-H cybrids. After cisplatin treatment, J cybrids showed increased gene expression of BAX, CASP3, and CYP51A, but lower levels of SFRP1 compared to untreated-J cybrids. The cisplatin-treated-H cybrids had elevated expression of CDKN1A/P21, which has a role in cisplatin toxicity, compared to untreated-H cybrids. The cisplatin-treated H had higher transcription levels of ABCC1, DHRS2/HEP27, and EFEMP1 compared to cisplatin-treated-J cybrids. Conclusions: Cybrid cell lines that contain identical nuclei but either H mtDNA mitochondria or J mtDNA mitochondria respond differently to cisplatin treatments suggesting involvement of the retrograde signaling (from mitochondria to nucleus) in the drug-induced cell death. Varying toxicities and transcription levels of the H vs. J cybrids after cisplatin treatment support the hypothesis that mtDNA variants play a role in the expression of genes affecting resistance and side effects of cisplatin

Comparision of Aqueous and Hydroalcoholic Extracts of Foeniculum Vulgare and Carum Copticum with Gentamicin on Escherichia Coli Strains: in Vitro Study

BACKGROUND AND OBJECTIVE: Due to bacterial resistance to antibiotics, new antibacterial agents is essential. In Persian medicine Fennel (Fuenoculum vulgare Mill.) and Ajwain (Carum copticum (L.) Benth. & Hook.f.) are recommended for the treatment of some infections. In this research, bacteriostatic and bactericidal effects of aqueous and hydroalcoholic extracts of fennel and Ajwain on E. coli were investigated. METHODS: In an in-vitro study 30 clinical isolates of urine culture of children with urinary tract infection from Amirkola Pediatric Hospital in Babol and a standard sample were used. Antibacterial effects of 4 grouos including aqueous and hydroalcoholic extracts of fennel and Ajwain by measuring the diameter of the inhibition zone using disc diffusion (concentrations 16, 32, 64, 128, 256 and 512 mg/disc) and determination of Minimum Inhibitory Concentrations (MIC) and Minimum Bactericidal Concentration (MBC) with Microdilution method was compared with Gentamicin (30mg/disc) as a positive control FINDINGS: There was no significant difference in inhibition zone with Gentamicin at concentrations of 64, 128, 256, and 512 mg/disc in standard and clinical samples. At concentrations of 16 and 32, Gentamicin was significantly better. The extract of 512 mg/disc (12.93±2.66) of hydroalcoholic extract of Carum copticum was significantly better than 256 mg/disc (9.53±1) (p=0.002). The MIC and MBC for standard samples were 4 and 8, respectively, and for clinical samples 3.83±2.36 and 5.8 mg / ml, respectively. Other extracts were not able to inhibit the growth of Escherichia coli. CONCLUSION: The results showed that the Hydroalcoholic extract of Carum copticum has bacteriostatic and bactericidal effects on standard and clinical isolates of Escherichia coli

An Investigation on the Nonlinear Free Vibration Analysis of Beams with Simply Supported Boundary Conditions Using Four Engineering Theories

The objective of this study is to present a brief survey on the geometrically nonlinear free vibrations of the Bernoulli-Euler, the Rayleigh, shear, and the Timoshenko beams with simple end conditions using the Homotopy Analysis Method (HAM). Expressions for the natural frequencies, the transverse deflection, postbuckling load-deflection relation to, and critical buckling load are presented. The results of nonlinear analysis are validated with the published results, and excellent agreement is observed. The effects of some parameters, such as slender ratio, the rotary inertia, and the shear deformation, are examined as other parameters are fixed

Modeling and optimization of nanoemulsion containing Sorafenib for cancer treatment by response surface methodology

The aim of this study is the development of nanoemulsions for intravenous administration of Sorafenib, which is a poorly soluble drug with no parenteral treatment. The formulation was prepared by a high energy emulsification method and optimized by response surface methodology. The effects of overhead stirring time, high shear rate, high shear time, and cycles of high-pressure homogenizer were studied in the preparation of nanoemulsion loaded with Sorafenib. Most of the particles in nanoemulsion are spherical in shape, the smallest particle size being 82.14nm. The results of the 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, a tetrazole reveal that the optimum formulation does not affect normal cells significantly in low drug concentrations but could remove the cancer cells. Finally, a formulation containing Sorafenib retained its properties over a period of 90days. With characterization, the study of the formulated nanoemulsion has the potential to be used as a parenteral nanoemulsion in the treatment of cancer. Graphical abstract Schematic figure of high pressure homogenizer device