Detection of the rotator cuff tears using a novel convolutional neural network from magnetic resonance image (MRI)

The rotator cuff tear is a common situation for basketballers, handballers, or other athletes that strongly use their shoulders. This injury can be diagnosed precisely from a magnetic resonance (MR) image. In this paper, a novel deep learning-based framework is proposed to diagnose rotator cuff tear from MRI images of patients suspected of the rotator cuff tear. First, we collected 150 shoulders MRI images from two classes of rotator cuff tear patients and healthy ones with the same numbers. These images were observed by an orthopedic specialist and then tagged and used as input in the various configurations of the Convolutional Neural Network (CNN). At this stage, five different configurations of convolutional networks have been examined. Then, in the next step, the selected network with the highest accuracy is used to extract the deep features and classify the two classes of rotator cuff tear and healthy. Also, MRI images are feed to two quick pre-trained CNNs (MobileNetv2 and SqueezeNet) to compare with the proposed CNN. Finally, the evaluation is performed using the 5-fold cross-validation method. Also, a specific Graphical User Interface (GUI) was designed in the MATLAB environment for simplicity, which allows for testing by detecting the image class. The proposed CNN achieved higher accuracy than the two mentioned pre-trained CNNs. The average accuracy, precision, sensitivity, and specificity achieved by the best selected CNN configuration are equal to 92.67%, 91.13%, 91.75%, and 92.22%, respectively. The deep learning algorithm could accurately rule out significant rotator cuff tear based on shoulder MRI

A proper protocol for isolation of retinal pigment epithelium from rabbit eyes

Background: Retinal pigment epithelium (RPE) is a hexagonal monolayer of pigmented cells located between the neural retina and the choroid with an essential role for visual function. So, isolation, propagation and maintenance of their functional integrity of RPE are crucial for research in vitro which next used for cell transplantation. The evaluation of features of RPE cells as a sheet after 14 days has not been reported yet. This study aimed to examine and compare three protocols for RPE isolation from rabbit eyes and obtain a proper protocol, which illustrated isolated RPE cells as a sheet cause to preserve their characterize even after 2 weeks. Materials and Methods: RPE cells were prepared from eyes of 24 rabbit eyes. After enucleating of eyes, anterior segment discarded and posterior segment cut to small pieces. Two of these procedures are based on the enzymatic digestion, but third protocol based on mechanical dissection. The culture cells harvested and morphological feature of cells assessed by phase-contrast microscope and then analyzed by reverse transcriptase-polymerase chain reaction (RT-PCR) and immunocytochemistry. Results: Evaluation of morphological feature showed that isolation of RPE cells as a sheet lead to preserve their hexagonal morphology. Immunocytochemistry and RT-PCR assessment demonstrated RPE cell cultured in sheet maintained their phenotypic feature, tight junction and the distribution of actin and cytokeratin filament. Comparison of three protocols showed that dissociation of RPE cells as a sheet was superior in the preserve of RPE characteristic. Conclusions: Isolation of RPE cells as a sheet maintains the integrity of these cells, this procedure promising a therapeutic approach, which is important for some retinal diseases

Mechanisms of the Effects of Zinc Oxide Nanostructures on Living Cells

Nowadays, nanotechnology and nanostructures, which are particles smaller than 100 nm in size at least in one dimension, are being widely used in various industries and consumer products, biomedical applications and environments. Unique properties of Zinc oxide (ZnO) nanostructures offer technological advantages for a variety of industrial and consumer products as well as show promise for biomedical application. They are used as an antibacterial agent in food packaging, such as UV absorbent in cosmetics and sunscreens. However, high concentrations of ZnO nanostructures have toxic effects on living organisms. The toxic effect of these nanostructures depends on target cell type, size, structure, and surface properties of nanostructures, as well as exposure routes. In this article, we discuss the toxic effect of ZnO nanostructures and different mechanisms including ROS production and the resulting oxidative stress, genomic toxicity, changes in gene expression and following protein production, epigenetic changes and inflammatory responses and apoptosis. Also, we will mention many in vivo studies about this nanoparticle

Evaluating Electroporation and Lipofectamine Approaches for Transient and Stable Transgene Expressions in Human Fibroblasts and Embryonic Stem Cells

Objective: Genetic modification of human embryonic stem cells (hESCs) is critical for their extensive use as a fundamental tool for cell therapy and basic research. Despite the fact that various methods such as lipofection and electroporation have been applied to transfer the gene of interest (GOI) into the target cell line, however, there are few reports that compare all parameters, which influence transfection efficiency. In this study, we examine all parameters that affect the efficiency of electroporation and lipofection for transient and long-term gene expression in three different cell lines to introduce the best method and determinant factor. Materials and Methods: In this experimental study, both electroporation and lipofection approaches were employed for genetic modification. pCAG-EGFP was applied for transient expression of green fluorescent protein in two genetically different hESC lines, Royan H5 (XX) and Royan H6 (XY), as well as human foreskin fibroblasts (hFF). For long-term EGFP expression VASA and OLIG2 promoters (germ cell and motoneuron specific genes, respectively), were isolated and subsequently cloned into a pBluMAR5 plasmid backbone to drive EGFP expression. Flow cytometry analysis was performed two days after transfection to determine transient expression efficiency. Differentiation of drug resistant hESC colonies toward primordial germ cells (PGCs) was conducted to confirm stable integration of the transgene. Results: Transient and stable expression suggested a variable potential for different cell lines against transfection. Analysis of parameters that influenced gene transformation efficiency revealed that the vector concentrations from 20-60 μg and the density of the subjected cells (5×105 and 1×106 cells) were not as effective as the genetic background and voltage rate. The present data indicated that in contrast to the circular form, the linearized vector generated more distinctive drug resistant colonies. Conclusion: Electroporation was an efficient tool for genetic engineering of hESCs compared to the chemical method. The genetic background of the subjected cell line for transfection seemed to be a fundamental factor in each gene delivery method. For each cell line, optimum voltage rate should be calculated as it has been shown to play a crucial role in cell death and rate of gene delivery

Possibilities in Germ Cell Research: An Engineering Insight

Germ cells (GCs) are responsible for fertility and disruptions in their development or function cause infertility. However, current knowledge about the diverse mechanisms involved in GC development and function is still in its infancy. This is mainly because there are low numbers of GCs, especially during embryonic development. A deeper understanding of GCs would enhance our ability to produce them from stem cells. In addition, such information would enable the production of healthy gametes for infertile couples. In this regard, pluripotent stem cells (PSCs) demonstrated a promising ability to produce GCs in vitro. In this review, we highlight recent advances in the field of tissue engineering that suggest novel strategies to enhance GC research

Enhancing developmental rate and quality of mouse single blastomeres into blastocysts using a microplatform

The present work reports the beneficial effects of using a microplatform on the development of mouse single blastomeres (SBs) to the blastocyst stage. Development of blastocysts from SBs separated from two‐ and four‐cell stage embryos (two‐ and four‐cell SBs) can provide a valuable supply both for couples who use fertility‐assisted techniques and farm animals. As a step forward, we introduce three chips that provide the possibility of culturing SBs separately, in groups, and in the vicinity of the intact embryo (co‐culture), while each well of the chips is assigned to an isolated SB. Two‐ and four‐cell SBs co‐cultured with intact embryos showed 97.1% and 76.6% developmental rates and up to 34.1% and 49.1% growth relative to the microdroplet method (control). We examined the quality of developed blastocysts by assessing the total cell number, the number of inner cell mass (ICM) according to the octamer‐binding transcription factor 4 marker (OCT4), and trophectoderm (TE). Co‐culture of SBs with an intact embryo in a chip with nanoscale culture medium volume also increased the cell population of the developed embryo. The ICM:TE ratio, which is the most important blastocyst quality parameter, also indicated that developed two‐cell SBs have a higher degree of similarity to intact embryos despite fewer numbers of total cells