Renal failures treatment has been faced with several problems during the last decades. Kidney tissue engineering has been created many hopes to improve treatment procedures with scaffold fabrication that can modulate kidney cells/ stem cells migration to the lesion site and increase the survival of these cells at that site with imitating the role of the kidney extracellular matrix. In this study, bone morphogenetic protein-7 (BMP7) as a vital factor for kidney development and regeneration was incorporated in the polycaprolactone (PCL) nanofibers and after morphological, mechanical, and biocompatible characterization, proliferation, and survival of the human embryonic kidney cells (HEK) were investigated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), flow cytometry, and gene expression while cultured on scaffolds. Mechanical properties of the PCL nanofibers modulated after combining with BMP7 and hydration degree, protein adsorption and cell adhesion were enhanced in PCL-BMP7 compared to the pure PCL. Proliferation rate and growth increased significantly in HEK cells cultured on PCL-BMP7 when compared with that of PCL and tissue culture plate, whereas these data were also confirmed via significant decrease in apoptotic genes expression level in HEK cell cultured on PCL-BMP7. According to the results, PCL-BMP7 demonstrated positive effects on the survival and J Cell Biochem. 2019;120:9859-9868.wileyonlinelibrary.com/journal/jcb

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Proper mixing in microfluidic devices has been a concern since the early development stages. Acoustic micromixers (active micromixers) attract significant attention due to their high efficiency and ease of implementation. Finding the optimal geometries, structures, and characteristics of acoustic micromixers is still a challenging issue. In this study, we considered leaf-shaped obstacle(s) having a multi-lobed structure as the oscillatory part(s) of acoustic micromixers in a Y-junction microchannel. Four different types of leaf-shaped oscillatory obstacles, including 1, 2, 3, and 4-lobed structures, were defined, and their mixing performance for two fluid streams was evaluated numerically. The geometrical parameters of the leaf-shaped obstacle(s), including the number of lobes, lobes’ length, lobes’ inside angle, and lobes’ pitch angle, were analyzed, and their optimum operational values were discovered. Additionally, the effects of the placement of oscillatory obstacles in three configurations, i.e., at the junction center, on the side walls, and both, on the mixing performance were evaluated. It was found that by increasing the number and length of lobes, the mixing efficiency improved. Furthermore, the effect of the operational parameters, such as inlet velocity, frequency, and intensity of acoustic waves, was examined on mixing efficiency. Meanwhile, the occurrence of a bimolecular reaction in the microchannel was analyzed at different reaction rates. It was proven that the reaction rate has a prominent effect at higher inlet velocities.

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Background: Acute lymphoblastic leukemia (ALL) is the most common malignancy in children. Epigenetic factors especially DNA methylation of promoter associated cytosine connected to guanine by phosphodiester bond (CpG islands) are considered as one of the most effective mechanisms in pathogenesis of ALL and have been demonstrated as a biomarker for lineage and subtype classification, prognostication, and disease progression. Objectives: In the present study, we examined the relationship between the promoter hypermethylation of the mir-200b and mir-34a regulator genes on the Notch signaling pathway in patients with ALL and controls in order to investigate association between promoter hypermethylation and development, progression and clinical factors. Methods: Genomic DNA was extracted from 60 samples (30 blood samples from leukemia patients and 30 normal samples) and modified by sodium bisulfite. Methylation-specific PCR was used to analyze the promoter methylation status of mir-34a and mir200b genes in the studied population. The results were analyzed with SPSS software version 20. Results: Our results showed significant association of mir-200b (P < 0.0001) and mir-34a (P < 0.004) genes hypermethylation with ALL. Also there was significant relationship between hypermethylation of mir-200b gene with family history (P = 0.003) and platelets (P = 0.01), and methylation of mir-34a gene with cancer state (P = 0.003) and Hb (P = 0.001) in ALL. Conclusions: In this study, we emphasized the important role of epigenetics on acute lymphoblastic leukemia development and progression. Our results showed that analysis of the methylation status of mir200b and mir-34a genes can provide novel prognostic markers for ALL.

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