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81.
Adriana Gregory Mohammad Mehrmohammadi Max Denis Mahdi Bayat Daniela L. Stan Mostafa Fatemi Azra Alizad 《PloS one》2015,10(9)
PurposeTo investigate the effects of macrocalcifications and clustered microcalcifications associated with benign breast masses on shear wave elastography (SWE).MethodsSuperSonic Imagine (SSI) and comb-push ultrasound shear elastography (CUSE) were performed on three sets of phantoms to investigate how calcifications of different sizes and distributions influence measured elasticity. To demonstrate the effect in vivo, three female patients with benign breast masses associated with mammographically-identified calcifications were evaluated by CUSE.ResultsApparent maximum elasticity (Emax) estimates resulting from individual macrocalcifications (with diameters of 2mm, 3mm, 5mm, 6mm, 9mm, 11mm, and 15mm) showed values over 50 kPa for all cases, which represents more than 100% increase over background (~21kPa). We considered a 2cm-diameter circular region of interest for all phantom experiments. Mean elasticity (Emean) values varied from 26 kPa to 73 kPa, depending on the macrocalcification size. Highly dense clusters of microcalcifications showed higher Emax values than clusters of microcalcification with low concentrations, but the difference in Emean values was not significant.ConclusionsOur results demonstrate that the presence of large isolated macrocalcifications and highly concentrated clusters of microcalcifications can introduce areas with apparent high elasticity in SWE. Considering that benign breast masses normally have significantly lower elasticity values than malignant tumors, such areas with high elasticity appearing due to presence of calcification in benign breast masses may lead to misdiagnosis. 相似文献
82.
Gila Pirzad Jahromi Mostafa Ghanei Seyed Kazem Hosseini Alireza Shamsaei Mazaher Gholipourmalekabadi Ameneh Koochaki Nushin Karkuki Osguei Ali Samadikuchaksaraei 《PloS one》2015,10(12)
Purpose
In patients with short-term exposure to the sulfur mustard gas, the delayed cellular effects on lungs have not been well understood yet. The lung pathology shows a dominant feature consistent with obliterative bronchiolitis, in which fibroblasts play a central role. This study aims to characterize alterations to lung fibroblasts, at the cellular level, in patients with delayed respiratory complications after short-term exposure to the sulfur mustard gas.Methods
Fibroblasts were isolated from the transbronchial biopsies of patients with documented history of exposure to single high-dose sulfur mustard during 1985–7 and compared with the fibroblasts of control subjects.Results
Compared with controls, patients’ fibroblasts were thinner and shorter, and showed a higher population doubling level, migration capacity and number of filopodia. Sulfur mustard decreased the in vitro viability of fibroblasts and increased their sensitivity to induction of apoptosis, but did not change the rate of spontaneous apoptosis. In addition, higher expression of alpha smooth muscle actin showed that the lung''s microenvironment in these patients is permissive for myofibroblastic differentiation.Conclusions
These findings suggest that in patients under the study, the delayed pulmonary complications of sulfur mustard should be considered as a unique pathology, which might need a specific management by manipulation of cellular components. 相似文献83.
Nabil E. Boutagy George W. Rogers Emily S. Pyne Mostafa M. Ali Matthew W. Hulver Madlyn I. Frisard 《Journal of visualized experiments : JoVE》2015,(104)
Skeletal muscle mitochondria play a specific role in many disease pathologies. As such, the measurement of oxygen consumption as an indicator of mitochondrial function in this tissue has become more prevalent. Although many technologies and assays exist that measure mitochondrial respiratory pathways in a variety of cells, tissue and species, there is currently a void in the literature in regards to the compilation of these assays using isolated mitochondria from mouse skeletal muscle for use in microplate based technologies. Importantly, the use of microplate based respirometric assays is growing among mitochondrial biologists as it allows for high throughput measurements using minimal quantities of isolated mitochondria. Therefore, a collection of microplate based respirometric assays were developed that are able to assess mechanistic changes/adaptations in oxygen consumption in a commonly used animal model. The methods presented herein provide step-by-step instructions to perform these assays with an optimal amount of mitochondrial protein and reagents, and high precision as evidenced by the minimal variance across the dynamic range of each assay. 相似文献
84.
85.
Mohammad Massumi Elham Hoveizi Parvaneh Baktash Abdollah Hooti Leili Ghazizadeh Samad Nadri Farzaneh Pourasgari Athena Hajarizadeh Masoud Soleimani Mohammad Nabiuni Mohammad R. Khorramizadeh 《Experimental cell research》2014
Due to pluripotency of induced pluripotent stem (iPS) cells, and the lack of immunological incompatibility and ethical issues, iPS cells have been considered as an invaluable cell source for future cell replacement therapy. This study was aimed first at establishment of novel iPS cells, ECiPS, which directly reprogrammed from human Eye Conjunctiva-derived Mesenchymal Stem Cells (EC-MSCs); second, comparing the inductive effects of Wnt3a/Activin A biomolecules to IDE1 small molecule in derivation of definitive endoderm (DE) from the ECiPS cells. To that end, first, the EC-MSCs were transduced by SOKM-expressing lentiviruses and characterized for endogenous expression of embryonic markers Then the established ECiPS cells were induced to DE formation by Wnt3a/Activin A or IDE1. Quantification of GSC, Sox17 and Foxa2 expression, as DE-specific markers, in both mRNA and protein levels revealed that induction of ECiPS cells by either Wnt3a/Activin A or IDE1 could enhance the expression level of the genes; however the levels of increase were higher in Wnt3a/Activin A induced ECiPS-EBs than IDE1 induced cells. Furthermore, the flow cytometry analyses showed no synergistic effect between Activin A and Wnt3a to derive DE-like cells from ECiPS cells. The comparative findings suggest that although both Wnt3a/Activin A signaling and IDE1 molecule could be used for differentiation of iPS into DE cells, the DE-inducing effect of Wnt3a/Activin A was statistically higher than IDE1. 相似文献
86.
87.
Mostafa A. Yehia Tarek S. El-Ammawi Khairia M. Al-Mazidi Mahmoud A. Abu El-Ela Hejab S. Al-Ajmi 《Mycopathologia》2010,169(4):241-246
Background
Fungal infections constitute a major health problem all over the world. Signs and symptoms induced by various dermatophytic infections are difficult to distinguish clinically from each other. So, characterization by in vitro culture is required for appropriate diagnosis and treatment as well as to study the epidemiological characteristics in a region. 相似文献88.
Rongjun Chen Najeem Folarin Vincent H.B. Ho David McNally David Darling Farzin Farzaneh Nigel K.H. Slater 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2010,878(22):1939-1945
Desthiobiotin-tagged lentiviral vectors have been metabolically produced by DBL producer cells in a 7,8-diaminopelargonic acid (7-DAPA) dependent manner for envelope independent, single-step affinity purification. 7-DAPA, which has little or no affinity for avidin/streptavidin, was synthesised and verified by NMR spectroscopy and mass spectrometry. By expressing the biotin acceptor, biotin ligase and desthiobiotin synthase bioD, DBL cells converted exogenous 7-DAPA into membrane-bound desthiobiotin. Desthiobiotin on the DBL cell surface was visualised by confocal microscopy and the desthiobiotin density was quantified by HABA-avidin assay. Desthiobiotin was then spontaneously incorporated onto the surface of lentiviral vectors produced by the DBL cells. It has been demonstrated by flow cytometry that the desthiobiotinylated lentiviruses were captured from the crude 7-DAPA-containing viral supernatant by Streptavidin Magnespheres® and eluted by biotin solution efficiently whilst retaining infectivity. The practical, high yielding virus purification using Pierce monomeric avidin coated columns indicates a highly efficient biotin-dependent recovery of infectious lentiviruses at 68%. The recovered lentiviral vectors had a high purity and the majority were eluted within 45 min. This 7-DAPA mediated desthiobiotinylation technology can be applied in scalable production of viral vectors for clinical gene therapy. 相似文献
89.
E.S. Abdel-Halim Mostafa M.G. Fouda I. Hamdy F.A. Abdel-Mohdy S.M. El-Sawy 《Carbohydrate polymers》2010,79(1):137
Linear electron beam radiation was used to induce grafting of glycidyl methacrylate/β-cyclodextrin mixture onto cotton fabric. Chlorohexidin diacetate was incorporated to the cavities of cyclodextrin fixed on the cotton fabric to form an inclusion complex having antimicrobial activity. After incorporating chlorohexidin diacetate, the fabric was subjected to several washing cycles to examine the durability of the antimicrobial finishing. Control and grafted cotton fabrics (before and after loading with antimicrobial agent) were characterized for their antimicrobial activity against different kinds of bacteria and fungi.Grafted fabrics loaded with antimicrobial agent were found to show good antimicrobial activity in comparison with control and grafted fabrics which are not loaded with antimicrobial agent. The grafted fabrics loaded with antimicrobial agent were found also to exhibit good antimicrobial activity after five washings and this lasting antimicrobial activity can be attributed to the inclusion complex formed between chlorohexidin diacetate molecules and the cavities of cyclodextrin. 相似文献
90.
Ahmad R. Naghsh-Nilchi Mostafa Aghashahi 《Biomedical signal processing and control》2010,5(2):147-157
In this paper, a new approach based on eigen-systems pseudo-spectral estimation methods, namely Eigenvector (EV) and MUSIC, and Multiple Layer Perceptron (MLP) neural network is introduced. In this approach, the calculated EEG (electroencephalogram) spectrum is divided into smaller frequency sub-bands. Then, a set of features, {maximum, entropy, average, standard deviation, mobility}, are extracted from these sub-bands. Next, incorporating a set of the EEG time domain features {standard deviation, complexity measure} with the spectral feature set, a feature vector is formed. The feature vector is then fetched into a MLP neural network to classify the signal into the following three states: normal (healthy), epileptic patient signal in a seizure-free interval (inter-ictal), and epileptic patient signal in a full seizure interval (ictal). The experimental results show that the classification of the EEG signals maybe achieved with approximately 97.5% accuracy and the variance of 0.095% using an available public EEG signals database. The results are among the best reported methods for classifying the three states aforementioned. This is a high speed with high accuracy as well as low misclassifying rate method so it can make the practical and real-time detection of this chronic disease feasible. 相似文献