Importance of analyzing the genomic instability in stem cell-based therapies

Stem cells are the main component in cell-based therapies and regenerative medicine to replace damaged tissues and cure various diseases. In regenerative medicine, in vitro stem cells’ culture is required for proliferation and differentiation. Although the risk of using these cells has not been established; but in addition to the possibility of spontaneous differentiation of undifferentiated cells after transplantation and teratoma formation, genome of these cells in culture media is instable and can be changed. Genomic instability can affect the transplantation safety of these cells or tissues derived from them. Genomic instability is one of the common features in stem cells and cancer. Hence, there is concern that the genomic instability during the manipulation of stem cells can be tumorigenic. Genomic instabilities are included in different sizes from point mutation to aneuploidy and mosaicism. Types of stem cells, culture conditions and some manipulation of cells such a long time are effective in creation and the rate of these instabilities. Therefore, in addition to optimizing the time and culture conditions, it is recommended to examine and follow the genomic abnormalities before therapeutic uses with appropriate methods

Genetic structure of Spanish and American stocks of cultivated rainbow trout, (Oncorhynchus mykiss)

Rainbow trout, Oncorhynchus mykiss is the most important cold water farmed fish in Iran. Several cultivated stocks have been imported to Iran and some fish farms have focuesd on the culture and breeding of these stocks all around the country. In this study, the genetic structure of Spanish and American stocks of rainbow trout was investigated using 4 pairs of microsatellite markers and 30 specimens of fish from each stock. Allele sizes at OMY77, OMY325, OMM1329 and OMM1332 loci were in the range of 102-178, 100-150, 122-198, 172-204 bps respectively. Average number of observed alleles in American and Spanish stocks was 11 and 11.5, respectively. Average number of effective alleles in Spanish and American stock was 8.65 and 8.03, respectively. The mean of observed heterozygosity for American and Spanish stocks were calculated as 0.59 and 0.63, respectively. The mean of expected heterozygosity for both stocks was very similar (around 0.86). The results showed a significant deviation from Hardy-Weinberg equilibrium at seven out of eight loci × stock. AMOVA test showed low (7%) genetic diversity between stocks, while the most (93%) genetic diversity was observed within stocks. Genetic identity and genetic distance between stocks were 0.831 and 0.186, respectively. Fixation index FST was calculated based on allelic frequency between two stocks was 0.012 with no significant difference between 2 stocks. The results of this study showed that while there was considerable genetic diversity within Spanish and American stocks, two stocks were very similar and showed very insignificant genetic differentiation based on 4 microsatellite studied loci

Electronic, dielectric and optical properties of two dimensional and bulk ice: a multi-scale simulation study

The intercalated water into nanopores exhibits anomalous properties such as ultralow dielectric constant.~Multi-scale modeling and simulations are used to investigate the dielectric properties of various crystalline two-dimensional ices and bulk ices. Although, the structural properties of two-dimensional (2D-) ices have been extensively studied, much less is known about their electronic and optical properties. First, by using density functional theory (DFT) and density functional perturbation theory (DFPT), we calculate the key electronic, optical and dielectric properties of 2D-ices. Performing DFPT calculations, both the ionic and electronic contributions of the dielectric constant are computed. The in-plane electronic dielectric constant is found to be larger than the out-of-plane dielectric constant for all the studied 2D-ices. The in-plane dielectric constant of the electronic response is found to be isotropic for all the studied ices. Secondly, we determined the dipolar dielectric constant of 2D-ices using molecular dynamics simulations (MDS) at finite temperature. The total out-of-plane dielectric constant is found to be larger than 2 for all the studied 2D-ices. Within the framework of the random-phase approximation (RPA), the absorption energy ranges for 2D-ices are found to be in the ultraviolet spectra. For the comparison purposes, we also elucidate the electronic, dielectric and optical properties of four crystalline ices (ice VIII, ice XI, ice Ic and ice Ih) and bulk water

Hygroscopic Expansion of Aesthetic Restorative Materials: One-Year Report

Objective: To measure the long-term linear hygroscopic expansion (LHE) of several materials using bulked and layered techniques.Materials and Methods: Seven materials were used; Fuji Cap II, Fuji II LC, Photac-Fil Aplicap, Vitremer, Dyract, Tetric and Z100. Ten specimens (6×4 mm) were made for each material using layered and bulked techniques (each group comprises five specimens). The specimens were stored in distilled water at 37°C. The length of each specimen was measured immediately after preparation, 24 hours, one week, one month, three months, six months, nine months and one year. This was used to calculate the percentage change in the length of materials. The mean LHE and standard deviation were calculated. Repeated measure analysis and paired sample t-test were used.Results: The type of material and time had a significant effect on LHE. Fuji Cap II and Fuji II LC exhibited no significant changes after one-year and one month, respectively.However, layered specimens of Photac-Fil Aplicap and Tetric showed constant expansionuntil six month, whereas bulked specimens reached the constant length at three months.Constant expansion was obtained for layered and bulked specimens of Dyract and Z100 at six month. Layered specimens of Vitremer showed no significant differences except between 24 hours and one year measurements. But in bulked specimens, the results at ninemonths and one year were significantly different from those obtained at three months and before.Conclusion: Fuji II showed no significant LHE and resin-modified glass ionomer cements (RMGICs) exhibited the highest LHE. Dyract maintained an intermediate LHE in comparison with RMGIC and composite resin

Computational analysis of magnetohydrodynamic natural convection in a square cavity with a thin fin

A numerical study of laminar natural convection in a square cavity with a thin fin that is under the influence of a uniform magnetic field is presented. The side walls of the cavity are kept at different temperatures and the horizontal walls are thermally insulated. An Adaptive Network-based Fuzzy Inference System (ANFIS) approach and an Artificial Neural Network (ANN) approach are developed, trained and validated using the results of Computational Fluid Dynamics (CFD) analysis. The effects of pertinent parameters on fluid flow and heat transfer characteristics are studied. Among these parameters are the Rayleigh number (103≤≤;106), the Hartmann number (0≤&Ha;≤;100), the position of the thin fin (0.1≤ Y p≤) and the length of the thin fin (0≤Lp≤0.8). The results show that ANFIS and ANN can successfully predict the fluid flow and heat transfer behaviour within the cavity in less time without compromising accuracy. In most cases, ANFIS can predict the results more accurately than ANN

Determinants of healthcare utilisation and predictors of outcome in colorectal cancer patients from Northern Iran

We aimed to assess healthcare utilisation (HU), its determinants, as well as its relationship with survival in colorectal cancer (CRC) patients. This study was conducted on incident CRC cases from Northern Iran. Information on HU was collected using a valid questionnaire, considering eight diagnostic and four therapeutic services. The results were categorised as good and poor HU. Multivariate logistic regression analysis was used to assess the relationship between HU and other variables. Cox regression analysis was performed to determine major predictors of survival. In total, 227 new cases of CRC were enrolled. HU could be assessed in 218 subjects (96). Living in rural areas was the strongest variable related to poor HU (adjusted OR, odds ratio=2.65; CI, confidence interval: 1.30-5.40). The median survival time was 40.5months. The 1-, 3- and 5-year survival rates were 71, 52 and 44 respectively. Cox regression analysis showed a significant lower survival rate in patients with poor HU (HR=2.3; CI: 1.46-3.64). HU was an independent predictor of survival in our CRC patients. Patients' place of residence was a significant determinant of HU. Regarding its effects on patients' outcome, HU and its determinants should be considered in designing CRC controlling programmes in our region and similar high-risk populations. © 2016 John Wiley & Sons Ltd

Metrics for measuring distances in configuration spaces

In order to characterize molecular structures we introduce configurational fingerprint vectors which are counterparts of quantities used experimentally to identify structures. The Euclidean distance between the configurational fingerprint vectors satisfies the properties of a metric and can therefore safely be used to measure dissimilarities between configurations in the high dimensional configuration space. We show that these metrics correlate well with the RMSD between two configurations if this RMSD is obtained from a global minimization over all translations, rotations and permutations of atomic indices. We introduce a Monte Carlo approach to obtain this global minimum of the RMSD between configurations