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Monitoring a biological tissue as a three dimensional (3D) model is of high importance. Both the measurement technique and the measuring electrode play substantial roles in providing accurate 3D measurements. Bioimpedance spectroscopy has proven to be a noninvasive method providing the possibility of monitoring a 3D construct in a real time manner. On the other hand, advances in electrode fabrication has made it possible to use flexible electrodes with different configurations, which makes 3D measurements possible. However, designing an experimental measurement set-up for monitoring a 3D construct can be costly and time consuming and would require many tissue models. Finite element modeling methods provide a simple alternative for studying the performance of the electrode and the measurement set-up before starting with the experimental measurements. Therefore, in this study we employed the COMSOL Multiphysics finite element modeling method for simulating the effects of changing the electrode configuration on the impedance spectroscopy measurements of a venous segment. For this purpose, the simulations were performed for models with different electrode configurations. The simulation results provided us with the possibility of finding the optimal electrode configuration including the geometry, number and dimensions of the electrodes, which can be later employed in the experimental measurement set-up.

Erfan Sadeghi,1,2 Sayed Mohsen Hosseini,1 Mehrdad Vossoughi,3 Ashraf Aminorroaya,4 Massoud Amini4 1Department of Epidemiology and Biostatistics, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran; 2Student Research Committee, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran; 3Oral and Dental Disease Research Center, Department of Dental Public Health, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran; 4Isfahan Endocrine and Metabolism Research Center, Isfahan University of Medical Sciences, Isfahan, IranCorrespondence: Sayed Mohsen HosseiniDepartment of Epidemiology and Biostatistics, School of Health, Isfahan University of Medical Sciences, Isfahan 81746-73461, IranTel +98 313 792 3251Fax +98 311 668 2509Email hosseini@hlth.mui.ac.irPurpose: Dyslipidemia is claimed to be associated with an increased risk of type 2 diabetes mellitus (T2DM). However, first-degree relatives (FDRs) of patients with T2DM are reported to be at higher risk. The aim of this study was to evaluate the association between serum lipid profile and T2DM incidence in FDRs.Patients and methods: Information on 1222 T2DM FDRs during 14 years of follow-up was retrieved. All individuals were examined for diabetes status and dyslipidemia once a year. We used a Bayesian joint longitudinal-survival model to assess the association.Results: Our data showed that a 10 mg/dL increase in triglycerides (TG), very-low-density lipoprotein (VLDL), and non-high-density lipoprotein (non-HDL) cholesterol levels during the follow-up period was associated with an increased risk of diabetes by 5%, 29%, and 6.6%, respectively. Moreover, for every one-unit increase in the TG to HDL ratio, the T2DM incidence increased by 35%. Subgroup analysis also showed that the increased risk of diabetes was significant only in female FDRs, so that a 10 mg/dL increase in TG and VLDL cholesterol level and a one-unit increase in TG to HDL ratio in female FDRs resulted in an increased risk of diabetes by 7.8%, 46%, and 64%, respectively. However, analysis of HDL, low-density lipoprotein (LDL), total cholesterol (TC), TC to HDL, and LDL to HDL cholesterol levels/ratios did not find any statistically significant associations.Conclusion: Increases in TG, VLDL, non-HDL cholesterol level, and TG to HDL ratio are associated with an increased risk of T2DM in FDRs, especially in female FDRs.Keywords: diabetes mellitus, joint model, longitudinal studies, survival

Mehdi Doosti-Telgerd,1 Fatemeh Sadat Mahdavi,2 Farzad Moradikhah,3 Mohammad Porgham Daryasari,1 Rahimeh Bayrami Atashgah,1 Banafsheh Dolatyar,4 Hamid Akbari Javar,5 Ehsan Seyedjafari,2 Iman Shabani,3 Ehsan Arefian,6 Farhood Najafi,7 Yaser Abdi,8 Mohsen Amini9 1Department of Pharmaceutical Biomaterials, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran; 2Department of Biotechnology, University of Tehran, Tehran, Iran; 3Department of Biomedical Engineering, Amirkabir University of Technology, Tehran, Iran; 4Department of Cell and Developmental Biology, School of Biological Sciences, College of Science, University of Tehran, Tehran, Iran; 5Department of Pharmaceutics, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran; 6Department of Microbiology, School of Biology, College of Science, University of Tehran, Tehran, Iran; 7Department of Resin and Additives, Institute for Color Science and Technology, Tehran, Iran; 8Department of Physics, University of Tehran, Tehran, Iran; 9Department of Medicinal Chemistry, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, IranCorrespondence: Hamid Akbari JavarDepartment of Pharmaceutics, Faculty of Pharmacy, Tehran University of Medical Sciences, P.O. Box: 1417614411, Tehran, IranTel +98 2164122205Email akbarijo@tums.ac.irObjective: The aim of this study is to fabricate functional scaffolds to gene delivery bone morphogenetic protein-2 (BMP-2) plasmid for bone formation in bone tissue engineering.Methods: Dendriplexes (DPs) of generation 4 polyamidoamin (G4-PAMAM)/BMP-2 plasmid were prepared through microfluidic (MF) platform. The physiochemical properties and toxicity of DPs were evaluated by DLS, AFM, FESEM and MTT assay. In order to create a suitable environment for stem cell growth and differentiation, poly-l-lactic acid (PLLA) and poly-l-lactic acid/poly (ethylene oxide) (PLLA/PEO) scaffolds containing hydroxyapatite nanoparticles (HA) and DPs were fabricated by the electrospinning method. The osteogenic potency of the scaffolds on human adipose tissue-derived mesenchymal stem cells (hASCs) was investigated.Results: The results revealed that tuning the physical properties of DPs by adjusting flow parameters in microfluidic platform can easily improve the cell viability compared to conventional bulk mixing method. Also, the result showed that the presence of HA and DPs in PLLA/PEO scaffold enhanced alkaline phosphatase (ALP) activity and increased the amount of deposited Ca, as well as, related to osteogenesis gen markers.Conclusion: This study indicated that on using the MF platform in preparation of DPs and loading them along with HA in PLLA/PEO scaffold, the osteogenic differentiation of hASCs could be tuned.Keywords: microfluidic, dendriplex, nanofibrous scaffolds, bone tissue engineering

Barbari GR, Dorkoosh FA, Amini M, et al. Int J Nanomedicine. 2017;12:3471–3483 The Editor and Publisher of International Journal of Nanomedicine wish to retract the published article. Concerns were raised regarding the alleged duplication of features within the image shown in Figure 4. The first author responded to our queries but was unable to provide the original images for Figure 4. The first author explained they were responsible for the preparation of the SEM images and wishes to apologize to the readers and other authors for any errors that may have been introduced to the image which led to the retraction of the paper. However, all the authors accept responsibility for the integrity of the reported research and agree with the decision to retract the article. Our decision-making was informed by our policy on publishing ethics and integrity and the COPE guidelines on retraction. The retracted article will remain online to maintain the scholarly record, but it will be digitally watermarked on each page as “Retracted”. This retraction relates to this paper

In recent years, magnesium oxide (MgO) has been considered by researchers as a new agent for the remediation of contaminated soils. In this paper, the effect of MgO and hydrated lime on the remediation of a clay soil contaminated with MTBE (Methyl Butyl Ether) was studied. The contaminated soil was made artificially by adding 2.25 g MTBE per kg of soil. MgO with different percentages (0.125, 0.25, 0.5, 5, 10, and 20%) and lime with 2.5, 5, and 10% percentages were added to the natural and contaminated soil. The results showed that by increasing the percentage of MgO or lime and curing time, the strength of natural and contaminated soil was improved. The results of the leaching tests showed that by adding 5, 10, or 20% MgO, all the existing MTBE in the soil samples were removed while for the smaller percentages of MgO (0.125, 0.25, and 0.5%) there was a decrease in the concentration of MTBE with time. The results of the leaching tests also revealed that the hydrated lime was effective in reducing the concentration of MTBE. The amount of reduction in the concentration of MTBE was dependent on the percentage of MgO or hydrated lime. The comparison of the results of the two binders showed that MgO was more effective than the hydrated lime in removing the MTBE from the soil. [ABSTRACT FROM AUTHOR]

One of the alternative versions of Shannon entropy is a measure of information which is called exponential entropy. Shannon and exponential entropies depend only on the event probabilities. These measures have also been extended to incorporate a set of weights associated with the events. Such weights may reflect some additional characteristics of the events such as their relative importance. In this paper, Axiomatic derivations and properties of weighted exponential entropy parallel to those achieved for weighted entropy are investigated. The relation between weighted exponential entropy of X and a strictly monotone and nonnegative function of X has obtained. The generalized weighted entropy and the generalized weighted exponential entropy for continuous random variable have been presented. [ABSTRACT FROM AUTHOR]

Independence test based on empirical copula does not perform well in the presence of weak dependency or when dependency occurs only in the tails. The copula density, which is estimated by a local likelihood probit transformation method, is used to detect the independence. In this article, three nonparametric tests of independence based on α-divergence and copula density are introduced. These tests are capable of considering weak dependency. The asymptotic consistency of the copula-based α-divergence estimator is also derived. In addition, the empirical powers of the proposed tests are computed through extensive simulations. The results show that the new tests outperform in small sample sizes or weak dependencies. Finally, an application in uranium exploration is presented to illustrate the applicability of the proposed tests. [ABSTRACT FROM AUTHOR]

Moluk Hadi Alijanvand,1–3 Ashraf Aminorroaya,2 Iraj Kazemi,4 Sima Aminorroaya Yamini,5 Mohsen Janghorbani,1,2 Masoud Amini,2 Marjan Mansourian1,21Department of Epidemiology and Biostatistics, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran; 2Isfahan Endocrine and Metabolism Research Centre, Isfahan University of Medical Sciences, Isfahan, Iran; 3Student Research Center, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran; 4Department of Statistics, College of Science, University of Isfahan, Isfahan, Iran; 5Department of Engineering and Mathematics, Sheffiled Hallam University, Sheffield, UKBackground: Moderately increased albuminuria (MIA) is strongly associated with hypertension (HTN) in patients with type 2 diabetic mellitus (T2DM). However, the association between risk factors and coexisting HTN and MIA remains unassessed.Objectives: This study aimed to determine both cross-sectional and longitudinal associations of risk factors with HTN and MIA comorbidity in patients with T2DM.Methods: A total of 1,600 patients with T2DM were examined at baseline and longitudinal data were obtained from 1,337 T2DM patients with at least 2 follow-up visits to assess the presence of HTN alone (yes/no), MIA alone (yes/no) and the coexistence of both (yes/no) in a 9-year open cohort study between 2004 and 2013. Bivariate mixed-effects logistic regression with a Bayesian approach was employed to evaluate associations of risk factors with HTN and MIA‎ comorbidity in the longitudinal assessment.Results: After adjustment for age and BMI, patients with uncontrolled plasma glucose, as a combined index of the glucose profile, were more likely to have HTN [odds ratio (OR): 1.73 with 95% Bayesian credible intervals (BCI) 1.29–2.20] and MIA [OR: 1.34 (‎95% BCI 1.13–1.62)]. The risks of having HTN and MIA were increased by a one-year raise in diabetes duration [with 0.89 (95% BCI 0.84–0.96) and 0.81 (95% BCI 0.73–0.92) ORs, respectively] and a one-unit increase in non-high-density lipoprotein-cholesterol (Non-HDL-C) [with 1.30 (95% BCI 1.23–1.34) and 1.24 (95% BCI 1.14–1.33) ORs, respectively].Conclusions: T2DM patients with HTN,‎ MIA, and the coexistence of both had uncontrolled plasma glucose, significantly higher Non-HDL-C, and shorter diabetes duration than the other T2DM patients. Duration of diabetes and uncontrolled plasma glucose index showed the stronger effects on HTN and MIA comorbidity than on each condition separately.Keywords: hypertension, moderately increased albuminuria, microalbuminuria, type 2 diabetes, comorbidity, risk factor

Rapid development in the field of tissue engineering necessitates implementation of monitoring methods for evaluation of the viability and characteristics of the cell cultures in a real-time, non-invasive and non-destructive manner. Current monitoring techniques are mainly histological and require labeling and involve destructive tests to characterize cell cultures. Bioimpedance measurement technique which benefits from measurement of electrical properties of the biological tissues, offers a non-invasive, label-free and real-time solution for monitoring tissue engineered constructs. This review outlines the fundamentals of bioimpedance, as well as electrical properties of the biological tissues, different types of cell culture constructs and possible electrode configuration set ups for performing bioimpedance measurements on these cell cultures. In addition, various bioimpedance measurement techniques and their applications in the field of tissue engineering are discussed.

Ghullam Reza Barbari,1 Farid Dorkoosh,1 Mohsen Amini,2 Nika Bahari Javan,1 Mohammad Sharifzadeh,3 Fateme Atyabi,1 Saeed Balalaie,4 Niyousha Rafiee Tehrani,5 Morteza Rafiee Tehrani1 1Department of Pharmaceutics, School of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran; 2Department of Medicinal Chemistry, School of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran; 3Department of Pharmacology, School of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran; 4Department of Chemistry, Khajeh Nasir Toosi University, Tehran, Iran; 5School of Medicine, Tehran University of Medical Sciences, Tehran, Iran Background: Despite years of experience and rigorous research, injectable insulin is the sole trusted treatment method to control the blood glucose level in diabetes type 1 patients, but injection of insulin is painful and poses a lot of stress to the patients, especially children, therefore, development of a non-injectable formulation of insulin is a major breakthrough in the history of medicine and pharmaceutical sciences. Methods: In this study, a novel peptide grafted derivative of chitosan (CPP-g- chitosan) is synthesized and its potential for oral delivery of proteins and peptides is evaluated. Drug-loaded nanoparticles were developed from this derivative using ionic gelation method with application of sodium tripolyphosphate (TPP) as a cross-linking agent. Human insulin was used as the model protein drug and release kinetic was studied at gastrointestinal pH. Finally the developed nanoparticles were filled into very tiny enteric protective capsules and its effects on blood glucose level are evaluated in laboratory animals. Results: Presence of the positively charged cell-penetrating peptide moiety in the structure of chitosan polymer had slight inhibitory effects on the release of insulin from the nanoparticles in simulated gastric fluid (pH 1.2) comparing to native chitosan. The nanoparticles were positively charged in gastrointestinal pH with size ranging from 180 nm to 326 nm. The polypeptide grafted to chitosan is a novel analog of Penetratin, presenting both the hydrophilic and hydrophobic characteristics altering the release behavior of the nanoparticles and significantly increase the absorption of insulin into the rat epithelium comparing to nanoparticles from simple chitosan. In-vivo results in diabetic rat proved that this nanoparticulate system can significantly lower the blood glucose levels in diabetic rats and remain effective for a duration of 9–11 hours. Conclusion: The results indicate that nanoparticles developed from this new peptide conjugated derivative of chitosan are very promising for oral delivery of proteins and peptides. Keywords: peptide grafted, oral delivery, cell-penetrating peptide, penetratin

Micromechanisms of ductile fracturing of DH-36 steel plates subjected to blast-induced pressure loads are studied experimentally using specially designed dynamic testing facilities. The sample geometry is such that it undergoes controllable fracturing, generally initiated near its center and grows first circumferentially and then radially. Selected fractured samples are sectioned normal to the fracture surfaces, at various intervals along the length of the fracture which extends into the necked and finally to the uniformly-deformed material. The thickness profile of the sample at each cross section is analyzed using optical and scanning electron microscopy. In this manner, we have been able to examine the microstructural evolution that has taken place, from necking inception to fracture initiation and growth, leading to a better understanding of the underpinning mechanisms of the fracturing of this material. The observed ductile fracture involves void nucleation, and void growth and coalescence, creating dimpled fracture surfaces. The examination of the microstructure of the deformed steel samples also revealed that the microstructure does not change significantly during the deformation and that there are no shearbands developing in and around the fracture zones. Based on the observed micro-scale deformation, a finite-element model was developed to further study the fracturing process, using a physics-based and experimentally-supported temperature- and rate-sensitive constitutive model for DH-36 steel. The finite-element model was capable of predicting the fracture process of the steel plates rather well. Additional finite-element simulations are performed to investigate the effect of the polyurea coating on the fracturing and fracture resistance of the plates. These also correlated well with the experimental results.