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This study investigated the potential of amniotic fluid stem cells (AFSCs) to synthesize mineralized extracellular matrix (ECM) within different porous scaffolds of collagen, poly-D,L-lactic acid (PDLLA), and silk fibroin. The AFSCs were initially differentiated by using an osteogenic medium in two-dimensional culture, and expression of specific bone proteins and the physiologic mineral production by the AFSCs were analyzed. In particular, during differentiation process, AFSCs expressed proteins like Runt-related transcription factor 2 (Runx2), Osterix, Osteopontin, and Osteocalcin with a sequential expression, analogous to those occurring during osteoblast differentiation, and produced extracellular calcium stores. AFSCs were then cultured on three-dimensional (3D) scaffolds and evaluated for their ability to differentiate into osteoblastic cells in vivo. Stem cells were cultured in vitro for 1 week in collagen, fibroin, and PDLLA scaffolds. The effect of predifferentiation of the stem cells in scaffolds on the subsequent bone formation in vivo was determined in a rat subcutaneous model. With the addition of a third dimension, osteogenic differentiation and mineralized ECM production by AFSCs were significantly higher. This study demonstrated the strong potential of AFSCs to produce 3D mineralized bioengineered constructs in vivo and suggests that fibroin may be an effective scaffold material for functional repair of critical size bone defects.

MATER (Maternal Antigen That Embryos Require) is an oocyte-specific protein dependent on the maternal genome and required for early embryonic development. The gene products expressed in oocytes play important roles in folliculogenesis, fertilization and pre-implantation development. The aim of this study was to characterize the localization and distribution pattern of the human MATER protein during follicular development and after ovulation, to determine its functional role. Immunocytochemistry experiments coupled with confocal and electron microscopy analysis were carried out to determine the ultrastructural localization of MATER in human ovarian tissue and in isolated oocytes, obtained during IVF procedures. Human cumulus cells were cultured, with or without cycloheximide, to confirm endogenous biosynthesis of the protein. Human MATER is detectable at the onset of the follicular maturation process, suggesting this protein has a role at earlier stages in the human compared with other mammalian species. The presence of MATER is specific to the oocyte and follicular cells that, during maturation, are spatially and functionally associated with the oocyte. The nuclear, nucleolar and mitochondrial localization hints at a possible role in RNA processing and the metabolic activity of the cell.

Extracorporeal shockwave lithotripsy (SWL) is one of the most common treatments for urinary stones. Despite technological improvements, it may cause side effects varying from minor reversible microscopic damage to severe large renal hematomas. The aim of our experimental study is to assess the efficacy of inosine in avoidance of acute renal damage after SWL.We used 25 Wistar rats that had previously had left nephrectomy. The rats were divided into three groups: group A consisted of 10 rats undergoing renal SWL; group B consisted of 10 rats that received adjunctive treatment with IP injection of inosine 40 minutes before SWL; and group C consisted of 5 rats that served as controls. N-acetylglucosaminidase (NAG) and lactate dehydrogenase (LDH) concentrations were evaluated 24 hours before and 24 hours after SWL. All the rats were subsequently sacrificed (4 rats in group A and 4 in group B at 48 hours post-SWL, and the remaining rats were sacrificed 30 days post-SWL). Renal tissue was submitted to histologic and electron microscopic examination to assess early and late alterations.NAG and LDH values were significantly increased after SWL in group A (P0.001), while no significant NAG and LDH differences were detected in group B (P0.16). Early histologic examination revealed a considerable amount of cellular degeneration in group A with ultrastructural vacuolization and disruption of lysosomal membranes; the tubular features and cellular structures appeared to be well preserved in group B. No late histologic alterations were evident in any of the specimens.Inosine is helpful and protective in the prevention of early microscopic damage to renal parenchyma due to SWL.

Recent improvements in techniques in clinical assisted reproduction have led to an increased interest in the cryopreservation of human ovarian tissue as a way of preserving fertility and ovarian steroidogenic activity in young cancer patients. Acceptable follicular survival in frozen-thawed human ovarian tissue has generally been reported. Since a 0.3 mol/l sucrose concentration in cryopreservation solutions evidently increases human oocyte survival after cryopreservation, the aim of this study was to observe the effect of sucrose concentrations of 0.2 mol/l and 0.3 mol/l on human ovarian tissue survival after thawing. Ovarian cortical slices from 10 patients, 22-36 years of age, were cryopreserved slowly using 0.2 mol/l or 0.3 mol/l sucrose with 1,2-propanediol (1.5 mol/l) as the cryoprotectants. Light and electron microscopy were used for the histological analyses. Results showed that both treatments produced an increase in damaged cells; however, the use of 0.3 mol/l sucrose showed a smaller percentage of damaged germ cells than 0.2 mol/l sucrose, and therefore was less detrimental to the thawed ovarian tissue. However as the damage occurred principally in the stroma and follicular cells rather than in the oocytes, the suitability of these cryopreservation protocols must be further evaluated prior to considering the use of stored ovarian cortex for autografting after thawing.