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Aims: In bone tissue engineering, the scaffold as a supportive structure, plays a vital role. Putting the scaffold in dynamic cell culture, such as perfusion bioreactor, makes the role of mechanical parameters such as shear stress and hydrodynamic pressure more important. On the other hand, these mechanical parameters are influenced by scaffold architecture. In this study, the effects of bone scaffold architecture on mechanical stimuli have been analyzed and their effects on the mesenchymal stem cell fate have been predicted.
Material & Methods: Using the tools of computer simulation, five bone scaffolds (Gyroid, high porous Gyroid, Diamond, IWP, and gradient architecture Gyroid) based on mathematical functions of minimal surfaces were designed and exposed in a simulated dynamic cell culture under the inlet velocities of 1, 10, 25, 50, and 100μm/s. Cell accumulation on the inner part of the scaffold was considered as an 8.5-micron layer. This layer was designed for Gyroid and IWP scaffolds.
Findings: Based on the results, Diamond scaffold showed the most efficient performance from the homogeneity of stresses point of view. In the presence of the cell layer, the von Mises stress was reported as 60 and 50 mPa on the Gyroid and IWP scaffolds, respectively which eases osteogenic differentiation.
Conclusion: In gradient architecture scaffolds under dynamic conditions, there is a gradient in shear stress that causes various signaling in different positions of theses scaffold and facilitates multi-differentiation of the cells on the same scaffold.

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Mechanical properties of living cells play an important role in helping to understand cell physiology and pathology. Evaluation of mechanical properties of cells may potentially lead to new mechanical diagnostic methods for some of these diseases. In this study, viscoelastic properties of the outer layer (cytoplasm and membrane) were extracted using standard linear solid model. Finite element modeling of the two cell layers is performed and the model is validated by experimental data. In the two-layer model, the effect of the radius of the nucleus and the location of the nucleus in the cell are investigated on the cell properties. By reducing the cytoplasmic radius ratio up to 43%, the whole cell properties follow the cytoplasmic properties and the effect of the nucleus can be neglected. The 50-second displacement change at a radial ratio of 0.53 increased to 4.5% compared to radial ratio of 1.58.  At a radial ratio of 0.43, a change in cell behavior was observed compared to the previous one, with a displacement change equals to 6.8% compared to radial ratio of 1.85 and a displacement reduction of 9.5% at a radial ratio of 0.53. The results demonstrate that the location of the nucleus and the ratio of the radius of the cytoplasm to the radius of the nucleus can effectively influence the viscoelastic properties and mechanical behavior of the cell.

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The number of microbial cells on the planet is much larger than the stars we know in the galaxies. However, the microbial diversity and their ecological network remain unknown, they have key roles on the Earth's ecosystems. Omics technologies such as metagenomics provide tools for recognizing a large part of these cryptic forms of life accurately, which are much higher than the uncultivated majority. One example is the diversity of the Vampyrellids from protista and micro-eukaryotes. Using meta-omics technologies, it found that the diversity within this one group equals that of the entire kingdom of fungi, and they are found in all corners of nature, from the oceans to terrestrial soils. It is noticeable that they are only one of the seven protista groups. In this article, in addition to introducing Omics technologies, some of big relevant projects and their results have also been discussed covering all of the Earth's environment. Metagenomics is the direct sequencing and characterization of genes and genomes present in complex microbial ecosystems (e.g. metagenomes). Viromics is the research of viral metagenome. In metatranscriptomics the mRNA is being analyzed which is due to its notoriously labile nature in environmental samples, its conservation and analyzing are the main challenges in this omics. Identification and measurement of various proteins that can directly measure microbial activity is performed in metaproteomics. Environmental metabolomics includes the study of low molecular weight metabolites generated from interactions between microorganisms, such as small eukaryotes, plants, animals, predators, abiotic stresses, and other stimulants.

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Background: Lung adenocarcinoma is the most primary histologic subtype of non-small cell lung cancer (NSCLC). Oxypeucedanin methanolate, a member of furanocoumarin, is a naturally occurring compound, which is isolated from Ferulago trifida Boiss, an endemic species in North-West of Iran.
Purpose: We attempt to uncover the capacities of oxypeucedanin methanolate to induce apoptosis and autophagy in NSCLC cells, as well as the underlying mechanism involved in this process.
Methods: The effect of oxypeucedanin methanolate on cell viability was evaluated on A549 cells by MTT assay. Flow cytometry assay was used to detect cellular apoptosis. Expression levels of BAX, caspase-3, BCL2 and LC3 in A549 cells were measured by Real time quantitative reverse transcription-polymerase chain reaction (Real time RT-PCR). A549 cells migration were analyzed using a wound‐healing assay.
Results: Oxypeucedanin methanolate inhibited A549 cell proliferation in dose- and time- dependent manner, as evaluated by MTT assay. The total apoptosis rate was (5.46%) for A549 cells not treated with oxypeucedanin methanolate. In contrast, the apoptosis rate was (29.6%) for A549 cells treated with oxypeucedanin methanolate at the concentration of 0.4 mM. Real time RT-PCR revealed that the mRNA expression of BAX, caspase-3 and LC3 were upregulated, while mRNA expression of BCL2 was downregulated. Untreated cell migration increased significantly after 72 hours.
Conclusion: Oxypeucedanin methanolate inhibits proliferation and it could induce apoptosis and autophagy of human non-small cell lung cancer cell line A549. Oxypeucedanin methanolate may be a good candidate for reducing of A549 cells metastasis. 

 

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Background and Objectives: Alzheimer’s disease is the most common neurodegenerative disease and the memory impairment is the main prominent symptom of this disease. The hippocampus of the brain, is the first region that undergoes changes in Alzheimer’s. Systems biology tools such as high-throughput techniques, enable us to explore signature genes involved in disease initiation and advancement which can be considered as new therapeutic and diagnostic candidates in complex diseases like Alzheimer’s.
Methods: A total of 85 samples obtained from the hippocampus of the brain of healthy individuals and individuals with Alzheimer’s were selected from two datasets. Differential expression analysis was performed independently for both datasets and the results were integrated. Genes with the same expression pattern in the two datasets were used to construct a gene-gene network using the STRING database. The obtained network analysis was performed to detect key genes associated with the disease.
Results: In this study, 73 genes with the same expression pattern were found in the two datasets. The obtained network analysis led to the identification of SNAP25, UNC13A, SYN2 and AMPH as key genes connected with Alzheimer’s disease.
Conclusion: The role of the reported key genes in endocytosis, neurotransmitters release and synaptic vesicle cycle facilitate proper functioning of memory. Expressional changes and mutations in each of these genes effect other pathways and lead to Alzheimer’s. Thus, the key genes reported in this study, can be considered as potential markers in developing diagnostic and therapeutic methods for Alzheimer’s.

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Evaluating the response of the stem cells to different mechanical stimulation is an important issue to obtain control over cell behavior in the culture environment. One of the effective parameters in the mechanoregulation of stem cells is the microstructure of scaffolds. Evaluating the effect of microstructure of scaffold in the lab environment is very complicated. Therefore, in this study, the effect of scaffold architecture on mechanical factors in the scaffold was investigated under oscillatory fluid flow by using numerical modeling. In this study, distribution of shear stress and fluid velocity in three types of scaffolds with spherical, cubical and regular hexagonal pores with length of 300, 350, 400, 450 and 500 micrometers were investigated by using computational fluid dynamics method. The results of the computational fluid dynamics model showed that the scaffold with spherical and cubic pores shape with length of 500 micrometers and scaffold with hexagonal pores with length of 450 micrometers experienced shear stress in the range of 0.1-10 mPa. This range of the shear stress is suitable for differentiation of the stem cell to bone cells. Moreover, the result of exerting oscillatory fluid flow to these scaffolds indicated that dead zones of the scaffold, where isn’t suitable for cell seeding, was decreased due to the access of fluid flow to the different area of scaffold. The results of this study can be used in a laboratory to achieve optimal stem cell culture to provide suitable environment culture for differentiation of stem cells toward the bone cell.