Neural Differentiation of Human-Induced Pluripotent Stem Cells (hiPSc) on Surface-Modified Nanofibrous Scaffolds Coated with Platelet-Rich Plasma

The field of tissue engineering exploits living cells in a variety of ways to restore, maintain, or enhance tissues and organs. Between stem cells, human induced pluripotent stem cells (hiPSCs), are very important due to their wide abilities. Growth factors can support proliferation, differentiation, and migration of hiPSCs. Platelet-rich plasma (PRP) could be used as the source of growth factors for hiPSCs. In the present study, proliferation and neural differentiation of hiPSCs on surface-modified nanofibrous Poly-l-lactic acid (PLLA) coated with platelet-rich plasma was investigated. The results of in vitro analysis showed that on the surface, which was modified nanofibrous scaffolds coated with platelet-rich plasma, significantly enhanced hiPSCs proliferation and neural differentiation were observed. Whereas the MTT ([3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide]) results showed biocompatibility of surface-modified nanofibrous scaffolds coated with platelet-rich plasma and the usage of these modified nanoscaffolds in neural tissue engineering in vivo is promising for the future.

     

Snd3 controls nucleus-vacuole junctions in response to glucose signaling

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Effects of different extracellular matrices and co-cultures on human limbal stem cell expansion in vitro

To elucidate the effect of extracellular matrices (ECMs) and related and nonrelated-limbal feeder cells as substitutes for the in vivo niche on the phenotype and genotype of the limbal stem cell (SC) expansion in vitro, human limbal SCs were used. The limbus explants were expanded on human amniotic membrane (AM), commercial ECMs including matrigel (MAT), collagen (COL), and control (no ECM) in presence and absence of feeder cells including human limbal fibroblasts (LFs), a limbus-specific cell and mouse embryonic fibroblasts (MEFs). Proliferation, cell death, immunocytochemistry, expression of specific genes, ultrastructural characteristics, and size and granularity of expanded human limbal SCs in different groups were evaluated. The growth, cell proliferation, and survival of limbal SCs were enhanced by AM and MAT matrices. Ultrastructure and expression of stemness markers revealed that there was no significance difference between AM and MAT. However, flow cytometric analysis showed that the size and granularity of cultured cells increased in the presence of MAT and COL as well as in no ECM group. Moreover, co-culturing of limbal explants with LFs and MEFs on AM and MAT groups, enhanced the expansion and survival of cultured cells in comparison with others. In conclusion, the cultivation of human limbal explants on AM co-culturing with human LFs promises to be a good model for preparing undifferentiated epithelial sheets suitable for transplantation.     

Anti-hyperglycemic effects of Eryngium billardierei F. Delaroche extract on insulin-resistance HepG2 cells in vitro

Background

Insulin resistance as a major problem is associated with type 2 diabetes mellitus. This study investigated the effect of Eryngium billardierei on insulin-resistance induced HepG2 cells.

Methods and results

MTT method was used to evaluate the viability of HepG2 cells treated with various doses of E. billardierei extract. An insulin-resistance model was established in HepG2 cells. Next, MTT assay and Acridine orange staining were performed to investigate the viability of cells in the vicinity of different concentrations of insulin, pioglitazone, and E. billardierei extract in an insulin-resistance media. The glucose uptake test was performed to select the optimal insulin concentration. Expression levels of IR, G6Pase, and PEPCK genes were assessed by real-time RT-PCR. According to obtained data, E. billardierei at concentrations of 0.5 and 1 mg/mL show no toxicity on cells. Furthermore, based on MTT assay and glucose uptake test 10^?5 mol/L insulin was chosen as the model group to induce insulin-resistance in HepG2 cells for gene expression analysis. Finally, 1 mg/mL E. billardierei not only induced no cytotoxicity but also showed an increase in the expression of IR as well as a reduction in G6Pase and PEPCK level compared to the control and model groups.

Conclusions

The obtained data indicated that 1 mg/mL E. billardierei might have an anti-insulin resistance effect on insulin-resistance HepG2 cells in vitro and could be a promising candidate with anti-hyperglycemic properties for diabetes treatments.

Graphical abstract

     

Genetic counseling in carriers of reciprocal translocations involving two autosomes

One of the main genetic causes involve in the pathogenesis of recurrent abortion is parental chromosomal abnormalities. The central concept in genetic counseling with such families is to estimate the probability of recurrence of unfavorable pregnancy outcomes. The main questions that consultants usually ask are: Why did this happen? What is the risk to be done again?Our cases were two families with repeated miscarriage. The pedigrees were drawn, the chromosomes of couples were studied, and estimation for recurrent risk was done. We tried to answer those two main questions and clear the results for them.Parental chromosome abnormalities were founded after karyotyping with GTG technique at 450 band resolution, revealing 46 chromosomes with balanced translocation of autosomes in one of the partner in both families. Recurrent risk was estimated as “high” for their future pregnancies in each family.Couples in which one partner is the carrier of such balanced translocation have increased risks of infertility, recurrent abortion, and delivery of chromosomally abnormal offspring. Genetic counseling of such couples, therefore, presents a unique challenge and should be considered in dealing with such families.     

Serum lipid profile in psoriatic patients: correlation between vascular adhesion protein 1 and lipoprotein (a)

Psoriasis is a chronic inflammatory skin disease characterized by excessive cellular replication. Apolipoproteins are genetically determined molecule whose role has been implied in cardiovascular pathology. Vascular adhesion protein?1 (VAP?1) is an adhesion molecule with an enzymatic activity that partakes in the migration process of lymphocytes into sites of inflammation. Our purpose was to evaluate the plasma lipid profiles, apolipoproteins (A1, B) and Lp (a) and VAP?1 in order to compare the lipid profile in psoriatic patients with non‐affected persons and correlation between VAP?1 and Lp (a). We determined serum concentrations of lipids, lipoproteins , apolipoproteins and VAP?1 in 90 patients with psoriasis and 90 age matched controls. Serum Lp (a), apo A1 and apo B were measured by immunoprecipitation assays, and the lipids and lipoproteins were measured by enzymatic methods.The VAP?1 were masured by ELISA method. The mean levels of total cholesterol, LDL, apo B and VAP?1 in patients with psoriasis were found to be significantly higher than those of healthy subjects (P<0.05. In psoriatic patients, elevation of VAP‐1 correlated with elevation of Lp (a) (p = 0.025). This study shows that high serum lipid level and VAP?1, is significantly more common in psoriasis. This fact may be responsible for higher prevalence of cardiovascular accident in psoriatic patients. Copyright © 2012 John Wiley & Sons, Ltd.     

One step forward to improve the latest method of antibacterial susceptibility testing of vitro-cultured bacteria: an implication for antibacterial efficacy of Enrofloxacine on <Emphasis Type="Italic">Aeromonas hydrophila</Emphasis>

Recently a new method of antibacterial susceptibility testing has been developed, which based on the reduction of the 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide (MTT) by bacteria. This study aimed to improve the latest developed method in terms of the period of time, concentration of bacterium, accuracy of assay and minimizing the toxic effect of the MTT solution. The commonly used broth microdilution method was compared in this study, as well. The minimum inhibition concentration (MIC) of the enrofloxacine against Aeromonas hydrophila as an opportunistic and ubiquitous bacterium was tested by using the improved MTT method. Using both methods showed that enrofloxacine exerts an excellent antibacterial effect against A. hidrophyla with MIC value of 62.5 ng/ml. The simplicity of the improved MTT method was shown with performing all steps of the assay in one plate, using rather low concentration of the bacterium (500 CFU/well) and shortening of the incubation time to 9 h. Moreover, 5–30 min incubation of bacteria with MTT solution excludes any toxic effect of tetrazolium salt against bacteria. Thus, our results suggest that enrofloxacine might be considered as a potent antibacterial agent against A. hydrophila induced contaminations. Moreover, MTT method with current improved characteristics such as short incubation time, low concentration of bacteria, and high sensitivity could be more practical alternative for the broth microdilution method in antibacterial susceptibility testing protocol.