Background: Slow graft healing in bone tunnels and a slow graft ligamentization process after anterior cruciate ligament (ACL) reconstruction are some of the reasons for prolonged rehabilitation. Aims: The purpose of this study was to determine if the use of platelet gel (PG) accelerates early graft revascularization after ACL reconstruction. Methods: PG was produced from autologous platelet-rich plasma and applied locally. We quantitatively evaluated the revascularization process in the osteoligamentous interface zone in the bone tunnels and in the intra-articular part of the graft by means of contrast-enhanced magnetic resonance imaging (MRI). Results: After 4-6 weeks, the PG-treated group demonstrated a significantly higher level of vascularization in the osteoligamentous interface (0.33 +/- 0.09) than the control group (0.16 +/- 0.09, p ( 0.001). In the intra-articular part of the graft, we found no evidence of revascularization in either group. Conclusion: Locally applied PG enhanced early revascularization of the graft in the osteoligamentous interface zone after ACL reconstruction.
F.22 Improvement to existing health/diagnostic methods/procedures
COBISS.SI-ID: 3697215The use of adult stem cells for the preparation of tissue engineered bone substitutes. PhD thesis, which presents the methods and the differentiation followed by the use of adult stem cells for the preparation of tissue engineered bone substitutes. In collaboration with Columbia University, New York, USA.
D.09 Tutoring for postgraduate students
COBISS.SI-ID: 246507264Our work is the first report about the expression of OCT4A pseudogenes 1, 3 and 4 during ES cells differentiation. Our results show that during differentiation of stem cells there is a developmentally regulated balance between the expression of embryonic genes and pseudogenes. The switch between one transcription pattern to the other depends on differentiation status of the cells. Since pseudogenes were expressed only in mature somatic cells we propose that the expression of pseudogenes can be used as a novel marker of cell differentiation status. Our data also indicates that it is necessary to critically evaluate existing published conclusions on the expression of OCT4A in different cell types, because pseudogene expression can lead to false positive results of molecular analysis. We examined the specificity of published primers for PCR and our data show that most of them are not specific and in addition to embryonic form also amplify several pseudogenes and isoform B. We also discovered a phenomenon called DAPI photoconversion that can easily lead to false positive results and data misinterpretation in imunocytochemistry experiments.
D.09 Tutoring for postgraduate students
COBISS.SI-ID: 266048512One of the ethically accepted, most abundant and largest reservoirs of adult stem cells is umbilical cord blood. Cord blood contains different stem cell types, mostly hematopoietic stem cells, but other stem cells with pluripotent potential can also be found. Those are umbilical cord blood embryonic like stem cells (CBE), which have the ability to differentiate into insulin producing cells in vitro. As they can be stored in biobanks, they can provide a potentially unlimited source of cells for transplantation and consequently effective approach to treat if not cure type 1 diabetes. The purpose of this thesis is to isolate stem cells from cord blood units and differentiate them into insulin producing cells. After collection and centrifugation of the cord blood, mononuclear cells were purified immunomagnetically with antibodies against lineage committed cells (negative selection). Differentiation towards pancreatic lineage was induced by 4 steps protocol. Isolated cells were expanded in expansion medium followed by differentiation in serum medium containing growth factors that initiate growth towards pancreatic lineage. After initial differentiation, cells were removed into maturation medium. Initial cell population and final step of maturation was analyzed by flow cytometry or by immunocytochemistry. Positive staining for pancreatic markers showed that cells in culture under the direction of certain growth factors and cytokines are capable of differentiation to insulin/c-peptide/glucagon containing pancreatic phenotype. By our method of isolation differentiation and maturation we proved that stem cells from cord blood have potential to develop into mature pancreatic cells, which are capable of secretion of hormones that regulate sugar homeostasis in the humans. The detection of c-peptide in cells with immunocytochemistry is the result of proteolytic processing and de novo of synthesis of hormone. Functional assays of these cells still have to be confirmed.
D.09 Tutoring for postgraduate students
COBISS.SI-ID: 764279The first Slovenian textbook for graduate study in the field of stem cells, which unifies the terminology in this field. Reviewers were experts in the field of biology, veterinary medicine, physiology, embryology and physiology. 289 p.
D.10 Educational activities
COBISS.SI-ID: 255815680