13 research outputs found

    The structure of Human Mesenchymal Stem Cells Differentiated into Cartilage in Micromass Culture System

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    Introduction: The aim of this study was to differentiate humanmesenchymal stem cells (hMSCs) into cartilage in a micromass culturesystem and study of their structure by light and electron microscopy.Material and Methods: Human bone marrow cells obtained from volunteerpatients were plated in 75-cm2 flasks and their MSCs were expandedthrough several sub-cultures. The passage 4 cells were used to establishmicromass culture system for chondrogenic differentiation. For this purpose,200,000 fibroblastic cells were placed in centrifuge tubes and pelleted at 250g for 5 minutes. About 0.5 ml chondrogenic induction medium was thenadded to the pellet and the culture incubated in 5% CO2 at 37°C for 21 days.Then, some pellets were utilized to evaluate chondrogenic differentiation byeither RT-PCR analysis of some cartilage marker molecules or specificstaining for detecting cartilage matrix, and other pellets were used for lightand electron microscopic study of differentiated tissue.Results: Primary culture of the bone marrow cells were initially composed ofthe spindle- and round shaped cells, from which the spindle cells remainedand expanded through several passages. At the end of differentiation period,RT-PCR analysis showed high production of collagen II and X and aggrecanmRNA inside the differentiated cells, and toluidine blue staining indicatedintermediate accumulation of the metachromatic matrix among the inducedcells. In general, light micrograph indicated a rather cellular state of thedifferentiated tissue in which the peripheral part had more metachromaticmatrix than central zone. More detailed study of the sections revealed thatinduced aggregates of the cells were composed externally of very thin layerof elongated cells reminiscent of perichondrium and internally a mass of ovalcells comprising the main part of the pellet. Ultra-thin sections showed thatthe cells in perichondrium-like layer were very similar to fibroblastic cells andthose located centrally had a set of well-developed organelles, characteristicof highly active cells. Some fat cells were seen in central zone.Conclusion: Cartilage tissue differentiated from MSCs in micromass culturesystem seemed to be structurally very similar to developing cartilage not toadult mature cartilage

    Testicular Tissue Vitrification: a Promising Strategy for Male Fertility Preservation

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    Destruction of spermatogonial stem cells in juvenile men survivors of pediatric cancers leads to infertility as a side effect of gonadotoxic therapies. Sperm freezing before cancer treatment is commonly used in the clinic for fertility preservation, but this method is not applicable for prepubertal boys due to the lack of mature sperm. In these cases, cryopreservation of testicular tissues is the only option for fertility preservation. Although controlled slow freezing (CSF) is the most common procedure for testicular tissue cryopreservation, vitrification can be used as an alternative method. Controlled vitrification has prevented cell damage and formation of ice crystals. Procedures were done easily and quickly with a brief exposure time to high concentration of cryoprotectants without expensive equipment. Different studies used vitrification of testicular tissues and they assessed the morphology of seminiferous tubules, apoptosis, and viability of spermatogonial cells. Transplantation of vitrified testicular tissue into infertile recipient mice as well as in vitro culture of vitrified tissues was done in previous studies and their findings showed complete spermatogenesis and production of mature sperm. Review articles usually have compared controlled slow freezing with vitrification. In this review, we focused only on the vitrification method and its results. Despite promising results, many studies have been done for finding an optimal cryopreservation protocol in order to successfully preserve fertility in prepubertal boys

    The Impact of Illicit Drug Use on Spontaneous Hepatitis C Clearance: Experience from a Large Cohort Population Study

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    Background and Aims: Acute hepatitis C infection usually ends in chronic infection, while in a minority of patients it is spontaneously cleared. The current population-based study is performed on a large cohort in Golestan province of Iran to examine the demographic correlates of Spontaneous Hepatitis C Clearance. Methods: Serum samples used in this study had been stored in biorepository of Golestan Cohort Study. These samples were evaluated for anti hepatitis C Virus by third generation Enzyme-linked immunosorbent assay (ELISA). Subjects who tested positive were then invited and tested by Recombinant Immunoblot Assay (RIBA) and Ribonucleic Acid Polymerase Chain Reaction test (PCR). If tested positive for RIBA, subjects were recalled and the two tests were re-done after 6 months. Those subjects who again tested positive for RIBA but negative for PCR were marked as cases of spontaneous clearance. Results: 49,338 serum samples were evaluated. The prevalence of Chronic Hepatitis C Virus (CHCV) infection based on PCR results was 0.31%. Among those who had acquired hepatitis C, the rate of SC was 38%. In multivariate analysis, illicit dru

    Application of platelet-rich plasma (PRP) improves self-renewal of human spermatogonial stem cells in two-dimensional and three-dimensional culture systems

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    Spermatogonial stem cells (SSCs) are very sensitive to chemotherapy and radiotherapy, so male infertility is a great challenge for prepubertal cancer survivors. Cryoconservation of testicular cells before cancer treatment can preserve SSCs from treatment side effects. Different two-dimensional (2D) and three-dimensional (3D) culture systems of SSCs have been used in many species as a useful technique to in vitro spermatogenesis. We evaluated the proliferation of SSCs in 2D and 3D culture systems of platelet-rich plasma (PRP). testicular cells of four brain-dead patients cultivated in 2D pre-culture system, characterization of SSCs performed by RT-PCR, flow cytometry, immunocytochemistry and their functionality assessed by xenotransplantation to azoospermia mice. PRP prepared and dosimetry carried out to determine the optimized dose of PRP. After preparation of PRP scaffold, cytotoxic and histological evaluation performed and SSCs cultivated into three groups: control, 2D culture by optimized dose of PRP and PRP scaffold. The diameter and number of colonies measured and relative expression of GFRa1 and c-KIT evaluated by real-time PCR. Results indicated the expression of PLZF, VASA, OCT4, GFRa1 and vimentin in colonies after 2D pre-culture, xenotransplantation demonstrated proliferated SSCs have proper functionality to homing in mouse testes. The relative expression of c-KIT showed a significant increase as compared to the control group (*: p < 0.05) in PRP- 2D group, expression of GFRa1 and c-KIT in PRP scaffold group revealed a significant increase as compared to other groups (***: p < 0.001). The number and diameter of colonies in the PRP-2D group showed a considerable increase (p < 0.01) as compared to the control group. In PRP- scaffold group, a significant increase (p < 0.01) was seen only in the number of colonies related to the control group. Our results suggested that PRP scaffold can reconstruct a suitable structure to the in vitro proliferation of SSCs

    Differentiation of human primary testicular cells in the presence of SCF using the organoid culture system

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    Purpose: Development of organoids using human primary testicular cells has remained a challenge due to the complexity of the mammalian testicular cytoarchitecture and culture methods. In this study, we generated testicular organoids derived from human primary testicular cells. Then, we evaluated the effect of stem cell factor (SCF) on cell differentiation and apoptosis in the testicular organoid model. Methods: The testicular cells were harvested from the three brain-dead donors. Human spermatogonial stem cells (SSCs) were characterized using immunocytochemistry (ICC), RT-PCR and flow cytometry. Testicular organoids were generated from primary testicular cells by hanging drop culture method and were cultured in three groups: control group, experimental group 1 (treated FSH and retinoic acid (RA)), and experimental group 2 (treated FSH, RA and SCF), for five weeks. We assessed the expression of SCP3 (Synaptonemal Complex Protein 3) as a meiotic gene, PRM2 (Protamine 2) as a post-meiotic marker and apoptotic genes of Bax (BCL2-Associated X Protein) and Bcl-2 (B-cell lymphoma 2), respectively by using RT-qPCR. In addition, we identified the expression of PRM2 by immunohistochemistry (IHC). Results: Relative expression of SCP3, PRM2 and Bcl-2 were highest in group 2 after five weeks of culture. In contrast, BAX expression level was lower in experimental group 2 in comparison with other groups. IHC analyses indicated the highest expression of PRM2 as a postmeiotic marker in group 2 in comparison to 2D culture and control groups but not find significant differences between experimental group 1 and experimental group 2 groups. Morphological evaluations revealed that organoids are compact spherical structures and in the peripheral region composed of uncharacterized elongated fibroblast-like cells. Conclusion: Our findings revealed that the testicular organoid culture system promote the spermatogonial stem cell (SSC) differentiation, especially in presence of SCF. Developed organoids are capable of recapitulating many important properties of a stem cell niche

    Correlates of HCV persistence versus spontaneous clearance in univariate analysis.

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    <p>The test was performed on all 247 patients who had a true positive ELISA test (cases of chronic HCV infection plus cases of spontaneous clearance).</p><p>Abbreviations: Non-IDU: Non Injecting Drug Use; IDU: Injecting Drug Use.</p
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