Crocin loaded nano-emulsions: Factors affecting emulsion properties in spontaneous emulsification

Spontaneous emulsification may be used for encapsulating bioactive compounds in food and pharmaceutical industry. It has several advantages over high energy and other low energy methods including, protecting sensitive compounds against severe conditions of high energy method and its ability to minimize surfactant, removal of cosurfactant and thermal stability compared with other low energy methods. In this study, we examined possibility of encapsulating highly soluble crocin in W/O micro-emulsions using spontaneous method which further could be used for making double emulsions. Nonionic surfactants of Span 80 and polyglycerol polyricinoleate (PGPR) were used for making micro-emulsions that showed the high potential of PGPR for spontaneous method. Surfactant to water ratio (SWR) was evaluated to find the highest amount of aqueous phase which can be dispersed in organic phase. Droplet size decreased by increasing SWR toward the SWR = 100 which had the smallest droplet size and then increased at higher levels of surfactant. By increasing SWR, shear viscosity increased which showed the high effect of PGPR on rheological properties. This study shows in addition to W/O micro-emulsions, spontaneous method could be used for preparing stable O/W micro-emulsions. © 2015 Elsevier B.V

Entrance surface dose measurement on the thyroid gland in orthopantomography: The need for optimization

Background: The anatomic position and proven radiosensitivity of the thyroid make it an organ of concern in dental X-ray examinations. A National Radiation Protection Department (NRPD)-sponsored pilot study carried out in the Dental Radiology Department of RUMS., to assess if the radiation dose in panoramic radiographies could be reduced without significant impairment of the subjective image quality. Materials and Methods: Thermoluminescent dosimetry (TLD) is widely acknowledged to be the recommended method for measuring entrance surface doses (ESD). In this study, ESD was measured using LiF thermoluminescent dosimeters (TLD-100) on the thyroid of 40 patients who had referred to the School of Dentistry, Rafsanjan University of Medical Sciences. Patients were not exposed to any additional radiation and the radiographs were used for diagnostic purposes. TLDs were calibrated with radiation energies similar to those commonly used in orthopantomography. Results: The overall mean ESD on the thyroid in orthopantomography was 0.071 ± 0.012 mGy (ranged from 0.01 to 0.40 mGy). The mean ESD for radiographies performed with 66 kVp (20 patients) and 68 kVp (20 patients) were 0.072 ± 0.019, and 0.070 ± 0.016 respectively. No statistically significant difference was found between these means. Conclusions: The measured surface doses in our study are inconsistent with the only one already reported about the same experiment. However, due to lack of national diagnostic reference levels for orthopantomography, it is not clear whether in case of the PM 2002 CC unit used in this experiment, reducing the radiation dose to a level that still keeps a diagnostically acceptable image quality is necessary

The need for national diagnostic reference levels: Entrance surface dose measurement in intraoral radiography

Background: Intraoral radiographies are the most frequent X-ray examinations in humans. According to International Commission on Radiation Protection (ICRP) recommendations, the selection of a diagnostic reference level (DRL) should be specific to a country or region. Critical organs such as thyroid gland are exposed to X-rays in intraoral radiography and these exposures should be kept as low as reasonably achievable. To assist the development of DRLs for intraoral radiography, a National Radiation Protection Department-sponsored pilot study was carried out. Materials and Methods: Thermoluminescent dosimetry (TLD) is widely acknowledged to be the recommended method for measuring entrance surface doses (ESD). In this study, ESD was measured using LiF thermoluminescent dosimeters (TLD-100) on the skin (either mandibular or maxillary arcs) of 40 patients. Three TLD chips were placed on the skin of each patient. The doses were averaged for each radiography and mean ESD of all patients calculated. Results: The mean ± SD entrance surface dose at the center of the beam on the patients' skin in intraoral radiography was 1.173 ± 0.606 mGy (ranged from 0.01 to 0.40 mGy). The mean ESD for male and female patients were 1.380 ± 0.823, and 1.004 ± 0.258 respectively. No statistically significant difference was found between these means. Despite its necessity, in national level, there is no published data on the diagnostic reference levels for intraoral radiography. However, the results obtained in this study are lower than those reported by investigators in other countries. Conclusion: In IR Iran, due to lack of large scale studies, no diagnostic reference levels have been set for X-ray diagnostic procedures. Due to lack of national diagnostic reference levels, it is not possible to clarify whether in intraoral radiographies any dose reduction techniques are needed. We intend to perform similar nationwide studies to set the diagnostic reference level for intraoal radio graphy

Model Development of Afterschool Programs in Cyberspace for Third grade Students of Guidance School

This research studies the design of a model of afterschool programs in cyberspace for third grade students of guidance school in 2012-2013 school year in Tehran City. For this purpose, the main parameters of the model were identified and their interrelations were studied, in order to identify the determining needs and major parameters of afterschool programs in cyberspace. A researcher-made questionnaire has been used for the students and a semi-structured interview for the principals, teachers and other educational staff. The data collected from the questionnaires and the interviews were processed and analyzed by SPSS and AMOS. Thus the conceptual model "after school programs in cyberspace " was confirmed. According to the needs analysis that was performed, the parameters of the after school programs in cyberspace were divided into two exogenous parameters of knowledge and skill and seven endogenous parameters of individual-social features, gaining knowledge extracurricular use, accessibility to information and sources, leisure, place of after school programs, and network features. Finally, the results indicated that the two parameters of individual –social features and place of after school programs in having the most direct and indirect effects on the model of after school programs in cyberspace. Further, in addition to identifying the major parameters of afterschool programs and studying the amount of effects of each of them. The causes and necessity of such programs were studied according to the qualitative and quantitative results

Fuzzy Modeling for Uncertain Nonlinear Systems Using Fuzzy Equations and Z-Numbers

In this paper, the uncertainty property is represented by Z-number as the coefficients and variables of the fuzzy equation. This modification for the fuzzy equation is suitable for nonlinear system modeling with uncertain parameters. Here, we use fuzzy equations as the models for the uncertain nonlinear systems. The modeling of the uncertain nonlinear systems is to find the coefficients of the fuzzy equation. However, it is very difficult to obtain Z-number coefficients of the fuzzy equations. Taking into consideration the modeling case at par with uncertain nonlinear systems, the implementation of neural network technique is contributed in the complex way of dealing the appropriate coefficients of the fuzzy equations. We use the neural network method to approximate Z-number coefficients of the fuzzy equations

Prediction of Glioblastoma Multiform Response to Bevacizumab Treatment Using Multi-Parametric MRI

Glioblastoma multiform (GBM) is a highly malignant brain tumor. Bevacizumab is a recent therapy for stopping tumor growth and even shrinking tumor through inhibition of vascular development (angiogenesis). This paper presents a non-invasive approach based on image analysis of multi-parametric magnetic resonance images (MRI) to predict response of GBM to this treatment. The resulting prediction system has potential to be used by physicians to optimize treatment plans of the GBM patients. The proposed method applies signal decomposition and histogram analysis methods to extract statistical features from Gd-enhanced regions of tumor that quantify its microstructural characteristics. MRI studies of 12 patients at multiple time points before and up to four months after treatment are used in this work. Changes in the Gd-enhancement as well as necrosis and edema after treatment are used to evaluate the response. Leave-one-out cross validation method is applied to evaluate prediction quality of the models. Predictive models developed in this work have large regression coefficients (maximum R2 = 0.95) indicating their capability to predict response to therapy

Differentiation of Glioma and Radiation Injury in Rats Using In Vitro Produce Magnetically Labeled Cytotoxic T-Cells and MRI

A limitation with current imaging strategies of recurrent glioma undergoing radiotherapy is that tumor and radiation injury cannot be differentiated with post contrast CT or MRI, or with PET or other more complex parametric analyses of MRI data. We propose to address the imaging limitation building on emerging evidence indicating that effective therapy for recurrent glioma can be attained by sensitized T-cells following vaccination of primed dendritic cells (DCs). The purpose of this study was to determine whether cord blood T-cells can be sensitized against glioma cells (U-251) and if these sensitized cytotoxic T-cells (CTLs) can be used as cellular magnetic resonance imaging probes to identify and differentiate glioma from radiation necrosis in rodent models.Cord blood T and CD14+ cells were collected. Isolated CD14+ cells were then converted to dendritic cells (DCs), primed with glioma cell lysate and used to sensitize T-cells. Phenotypical expression of the generated DCs were analyzed to determine the expression level of CD14, CD86, CD83 and HLA-DR. Cells positive for CD25, CD4, CD8 were determined in generated CTLs. Specificity of cytotoxicity of the generated CTLs was also determined by lactate dehydrogenase (LDH) release assay. Secondary proliferation capacity of magnetically labeled and unlabeled CTLs was also determined. Generated CTLs were magnetically labeled and intravenously injected into glioma bearing animals that underwent MRI on days 3 and 7 post- injection. CTLs were also administered to animals with focal radiation injury to determine whether these CTLs accumulated non-specifically to the injury sites. Multi-echo T2- and T2*-weighted images were acquired and R2 and R2* maps created. Our method produced functional, sensitized CTLs that specifically induced U251 cell death in vitro. Both labeled and unlabeled CTLs proliferated equally after the secondary stimulation. There were significantly higher CD25 positive cells (p = <0.006) in CTLs. In addition, T2- and T2*-weighted MR images showed increased low signal intensity areas in animals that received labeled CTLs as compared to the images from animals that received control cells. Histological analysis confirmed the presence of iron positive cells in sites corresponding to MRI low signal intensity regions. Significant differences (p = <0.001) in tumor R2 and R2* values were observed among the groups of animals. Animals with radiation injury exhibited neither MRI hypointense areas nor presence of iron positive cells.Our results indicate that T-cells can be effectively sensitized by in vitro methods and used as cellular probes to identify and differentiate glioma from radiation necrosis

Can environmental or occupational hazards alter the sex ratio at birth? A systematic review

More than 100 studies have examined whether environmental or occupational exposures of parents affect the sex ratio of their offspring at birth. For this review, we searched Medline and Web of Science using the terms ‘sex ratio at birth’ and ‘sex ratio and exposure’ for all dates, and reviewed bibliographies of relevant studies to find additional articles. This review focuses on exposures that have been the subject of at least four studies including polychlorinated biphenyls (PCBs), dioxins, pesticides, lead and other metals, radiation, boron, and g-forces. For paternal exposures, only dioxins and PCBs were consistently associated with sex ratios higher or lower than the expected 1.06. Dioxins were associated with a decreased proportion of male births, whereas PCBs were associated with an increased proportion of male births. There was limited evidence for a decrease in the proportion of male births after paternal exposure to DBCP, lead, methylmercury, non-ionizing radiation, ionizing radiation treatment for childhood cancer, boron, or g-forces. Few studies have found higher or lower sex ratios associated with maternal exposures. Studies in humans and animals have found a reduction in the number of male births associated with lower male fertility, but the mechanism by which environmental hazards might change the sex ratio has not yet been established