ABSTRACT
Objective: Three-dimensional [3D] biomimetic nanofiber scaffolds have widespread applications in biomedical tissue engineering. They provide a suitable environment for cellular adhesion, survival, proliferation and differentiation, guide new tissue formation and development, and are one of the outstanding goals of tissue engineering. Electrospinning has recently emerged as a leading technique for producing biomimetic scaffolds with micro to nanoscale topography and a high porosity similar to the natural extracellular matrix [ECM]. These scaffolds are comprised of synthetic and natural polymers for tissue engineering applications. Several kinds of cells such as human embryonic stem cells [hESCs] and mouse ESCs [mESCs] have been cultured and differentiated on nanofiber scaffolds. mESCs can be induced to differentiate into a particular cell lineage when cultured as embryoid bodies [EBs] on nano-sized scaffolds
Materials and Methods: We cultured mESCs [2500 cells/100 Mul] in 96-well plates with knockout Dulbecco's modified eagle medium [DMEM-KO] and Roswell Park Memorial Institute-1640 [RPMI-1640], both supplemented with 20% ESC grade fetal bovine serum [FBS] and essential factors in the presence of leukemia inhibitory factor [LIF]. mESCs were seeded at a density of 2500 cells/100 Mul onto electrospun polycaprolactone [PCL] nanofibers in 96-well plates. The control group comprised mESCs grown on tissue culture plates [TCP] at a density of 2500 cells/100 Mul. Differentiation of mESCs into mouse hematopoietic stem cells [mHSCs] was performed by stem cell factor [SCF], interleukin-3 [IL-3], IL-6 and Fms-related tyrosine kinase ligand [Flt3-L] cytokines for both the PCL and TCP groups. We performed an experimental study of mESCs differentiation
Results: PCL was compared to conventional TCP for survival and differentiation of mESCs to mHSCs. There were significantly more mESCs in the PCL group. Flowcytometric analysis revealed differences in hematopoietic differentiation between the PCL and TCP culture systems. There were more CD34+ [Sca1+] and CD133+ cells subpopulations in the PCL group compared to the conventional TCP culture system
Conclusion: The nanofiber scaffold, as an effective surface, improves survival and differentiation of mESCs into mHSCs compared to gelatin coated TCP. More studies are necessary to understand how the topographical features of electrospun fibers affect cell growth and behavior. This can be achieved by designing biomimetic scaffolds for tissue engineering
Materials and Methods: We cultured mESCs [2500 cells/100 Mul] in 96-well plates with knockout Dulbecco's modified eagle medium [DMEM-KO] and Roswell Park Memorial Institute-1640 [RPMI-1640], both supplemented with 20% ESC grade fetal bovine serum [FBS] and essential factors in the presence of leukemia inhibitory factor [LIF]. mESCs were seeded at a density of 2500 cells/100 Mul onto electrospun polycaprolactone [PCL] nanofibers in 96-well plates. The control group comprised mESCs grown on tissue culture plates [TCP] at a density of 2500 cells/100 Mul. Differentiation of mESCs into mouse hematopoietic stem cells [mHSCs] was performed by stem cell factor [SCF], interleukin-3 [IL-3], IL-6 and Fms-related tyrosine kinase ligand [Flt3-L] cytokines for both the PCL and TCP groups. We performed an experimental study of mESCs differentiation
Results: PCL was compared to conventional TCP for survival and differentiation of mESCs to mHSCs. There were significantly more mESCs in the PCL group. Flowcytometric analysis revealed differences in hematopoietic differentiation between the PCL and TCP culture systems. There were more CD34+ [Sca1+] and CD133+ cells subpopulations in the PCL group compared to the conventional TCP culture system
Conclusion: The nanofiber scaffold, as an effective surface, improves survival and differentiation of mESCs into mHSCs compared to gelatin coated TCP. More studies are necessary to understand how the topographical features of electrospun fibers affect cell growth and behavior. This can be achieved by designing biomimetic scaffolds for tissue engineering
ABSTRACT
The peroxisome proliferator-activated receptors [PPARs] are a group of nuclear receptor proteins whose functions as transcription factors regulate gene expressions. PPARs play essential roles in the regulation of cellular differentiation, development, and metabolism [carbohydrate, lipid, protein], and tumorigenesis of higher organisms. This study attempts to determine the effect of baicalin, a PPAR? activator, on erythroid differentiation of cluster of differentiation 133+ [CD133+] cord blood hematopoietic stem cells [HSCs]. In this experimental study, in order to investigate the effects of the PPAR? agonists baicalin and troglitazone on erythropoiesis, we isolated CD133+ cells from human umbilical cord blood using the MACS method. Isolated cells were cultured in erythroid-inducing medium with or without various amounts of the two PPAR? activators [baicalin and troglitazone]. Erythroid differentiation of CD133+ cord blood HSCs were assessed using microscopic morphology analysis, flow cytometric analysis of erythroid surface markers transferrin receptor [TfR] and glycophorin A [GPA] and bycolony forming assay. Microscopic and flow cytometric analysis revealed the erythroid differentiation of CD133+ cord blood HSCs under applied erythroid inducing conditions. Our flow cytometric data showed that the TfR and GPA positive cell population diminished significantly in the presence of either troglitazone or baicalin. The suppression of erythroid differentiation in response to PPAR? agonists was dose-dependent. Erythroid colony-forming ability of HSC decreased significantly after treatment with both PPAR? agonists but troglitazone had a markedly greater effect. Our results have demonstrated that PPAR? agonists modulate erythroid differentiation of CD133+ HSCs, and therefore play an important role in regulation of normal erythropoiesis under physiologic conditions. Thus, considering the availability and application of this herbal remedy for treatment of a wide range of diseases, the inhibitory effect of baicalin on erythropoiesis should be noted
ABSTRACT
Superparamagnetic iron oxide nanoparticles [SPIONs] have been used to label mammalian cells and to monitor their fate in vivo using magnetic resonance imaging [MRI]. However, the effectiveness of phenotype of labeled cells by SPIONs is still a matter of question. The aim of this study was to investigate the efficiency and biological effects of labeled mouse embryonic stem cells [mESCs] using ferumoxide- protamine sulfate complex. In an experimental study, undifferentiated mESCs, C571 line, a generous gift of Stem Cell Technology Company, were cultured on gelatin-coated flasks. The proliferation and viability of SPION-labeled cells were compared with control. ESCs and embryoid bodies [EBs] derived from differentiated hematopoietic stem cells [HSCs] were analyzed for stage-specific cell surface markers using fluorescence-activated cell sorting [FACS]. Our observations showed that SPIONs have no effect on the self-renewal ability of mESCs. Reverse microscopic observations and prussian blue staining revealed 100% of cells were labeled with iron particles. SPION-labeled mESCs did not significantly alter cell viability and proliferation activity. Furthermore, labeling did not alter expression of representative surface phenotypic markers such as stage-specific embryonic antigen 1 [SSEA1] and cluster of differentiation 117 [CD117] on undifferentiated ESC and CD34, CD38 on HSCs, as measured by flowcytometry. According to the results of the present study, SPIONs-labeling method as MRI agents in mESCs has no negative effects on growth, morphology, viability, proliferation and differentiation that can be monitored in vivo, noninvasively. Non-invasive cell tracking methods are considered as new perspectives in cell therapy for clinical use and as an easy method for evaluating the placement of stem cells after transplantation
ABSTRACT
Unfortunately, the prevalence of cesarean section has increased in recent years. Whereas awareness of the prevalence and causes is inevitable for planning and effective interventions, so aim of this study has designed and conducted for reviewing of systematic Prevalence and caesarean causes in Iran. In this meta-analysis, the required information have been collected using several keywords which are Cesarean section rate, Cesarean section prevalence, delivery, childhood, childbirth, relative causes, relative frequency, Iran and their Persian equivalents have been collected from databases such as CINAHL, Science Direct, PubMed, Magiran, SID, Iranmedex. Finally, we found 706 related articles and selected 34 articles among them for studying of cesarean Prevalence. We used CMA software with random model for Meta-Analysis. The prevalence of Cesarean was estimated48%. Using content analysis, Factors influencing the incidence of cesarean section were divided to 3 categories including social and demographic factors, obstetric-medical causes and non-obstetric-medical causes. Maternal education and grand multiparity in the field of demographic and social factors, previous cesarean in the field of obstetric-medical causes and fear of normal-vaginal delivery [NVD] and doctor's suggestion in the field of non-obstetric-medical causes were major causes of Cesarean. According to the high prevalence of caesarean section and it upward development, it seems to be essential designing and implementing of programs and interventions effectiveness including providing of Possibility of painless childbirth and education and psychological interventions, increasing of quality of natural delivery services, proper culture and prohibiting of doctors from Personal opinions and profit