The aim of this study was to compare (a) two different umbilical cord blood (UCB) collection methods while the placenta is still in the uterus (in utero), and (b) to evaluate the efficacy of four cryopreservation protocols based on UCB haematopoiestic stem cell (HSC) recovery. We analysed UCB samples collected with our original collection system designed for active Syringe/Flush/Syringe method or by standard in utero method. For comparing different cryopreservation procedures, dimethyl sulphoxide (DMSO) at final concentration of 5 and 10% was used and combined with our own controlled-rate or uncontrolled-rate cryopreservation. A total of 99 samples were collected. A significantly higher UCB volume, total nucleated cell and mononuclear cell were seen following the first collection strategy (n= 49; mean +/- SD, 103 +/- 35.4 mL; 12.34 +/- 5.27 x 10(8); 595 +/- 3.47 x 10(6)) vs. the second strategy (n= 50; 86 +/- 29.3 mL; 9.87 +/- 4.47; 424 +/- 2.82 x 10(6)) respectively (P < 0.01). The discard rate was 14% for the first and 36% for the second collection strategy (P < 0.01). It was shown that the most efficient procedure was the controlled-rate protocol combined with lower (5%) DMSO concentration. Using active Syringe/Flush/Syringe method, we collected UCB with greater volumes and with lower discard rate compared to the standard by gravity technique. The data presented also showed much better recovery of UCB cells when controlled-rate freezing procedure and 5% DMSO were combined.

The use of strictly equalized (1 degrees C/min) controlled-rate freezing, combined with an intensified cooling rate (2 degrees C/min) during the liquid-to-solid-phase transition period, allows advanced quantitative and qualitative PLT recovery, even though the minor intergroup differences for some variables were observed.

To date, three types of dental stem cells have been isolated: Dental Pulp Stem Cells (DPSC), Stem Cells From Human Exfoliated Deciduous Teeth (SHED) and Immature Dental Pulp Stem Cells (IDPC). These dental stem cells are considered as mesenchymal stem cells. They reside within the perivascular niche of dental pulp. They are highly proliferative, clonogenic, multipotent and are similar to mesenchymal Bone Marrow Stem Cells (BMSC). Also, they have high plasticity and can be easy isolated. The expressions of the alkaline phosphatase gene, dentin matrix protein 1 and dentinsialophosphoprotein are verified in these cells. Analyses of gene expression patterns indicated several genes which encode extracellular matrix components, cell adhesion molecules, growth factors and transcription regulators, cell signaling, cell communication or cell metabolism. In both conditions, in vivo and in vitro, these cells have the ability to differentiate into odontoblasts, chondrocytes, osteoblasts, adipocytes, neurons, melanocytes, smooth and skeletal muscles and endothelial cells. In vivo, after implantation, they have shown potential to differentiate into dentin but also into tissues like bone, adipose or neural tissue. In general, DPSCs are considered to have antiinflammatory and immunomodulatory abilities. After being grafted into allogenic tissues these cells are ableto induce immunological tolerance. Immunosuppressive effect is shown through the ability to inhibit proliferation of T lymphocytes. Dental pulp stem cells open new perspectives in therapeutic use not only in dentin regeneration, periodontal tissues and skeletoarticular, tissues of craniofacial region but also in treatment of neurotrauma, autoimmune diseases, myocardial infarction, muscular dystrophy and connective tissue damages

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Background/Aim. The last decade has been profoundly marked by persistent attempts to use ex vivo expanded and manipulated mesenchymal stem cells (MSCs), as a tool in different types of regenerative therapy. In the present study we described immunophenotype and the proliferative and differentiation potential of cells isolated from pulp remnants of exfoliated deciduous teeth in the final phase of root resorption. Methods. The initial adherent cell population from five donors was obtained by the outgrowth method. Colony forming unit-fibroblast (CFU-F) assay was performed in passage one. Cell expansion was performed until passage three and all tests were done until passage eight. Cells were labeled for early mesenchymal stem cells markers and analysis have been done using flow cytometry. The proliferative potential was assessed by cell counting in defined time points and population doubling time was calculated. Commercial media were used to induce osteoblastic, chondrogenic and adipogenic differentiation. Cytology and histology methods were used for analysis of differentiated cell morphology and extracellular matrix char-

The influence of toluene exposure on some biochemical and hematological parameters was investigated in adult female Wistar rats. The animals were subjected to intraperitoneal administration of toluene diluted in propylene glycol and the diluent alone for 3, 7 and 11 consecutive days at the same time intervals. The effects of toluene and propylene glycol were evaluated biochemically by determining the plasma concentrations of total proteins albumin and ceruloplasmin (Cp) together with erythrocyte malondialdehyde (MDA), and hematological indices from peripheral blood and bone marrow. The biochemical acute phase response was manifested by an elevated Cp concentration in all experimental animals. The markedly enhanced MDA concentration and statistically significant decrease in albumin level in toluene treated rats, indicated damage, to blood vessel endothelia. Alterations of leukocytes of peripheral blood and bone marrow (BM) granulocytic-monocytic progenitor cells were typical of an inflammatory response, with stimulation of granulo-monocytopoiesis. Therefore, it can be assumed that both toluene and propylene glycol mediated sterile peritonitis and oxidative stress injury, with changes intensified by toluene action

Serum iron concentration and iron saturation of transferrin (Trf) are measures of body iron stores after administration of iron supplements. In clinical and experimental research, the complex determination of Trf was replaced by the simple determination of total iron binding capacity (TIBC). The objective of this work was to define if TIBC could be an adequate measure for Trf in neonatal piglets after i.m. iron administration. Treated piglets received 150 mg of iron-dextran i.m. the first day of life, and were compared to the untreated control group. Prior to iron administration, as well as on days 2, 8 and 12 after iron administration, serum iron and TIBC concentration were analyzed by an automatized chemical analyzer and Trf was determined by densitometry of electrophoretic strips. Our results show that regardless of iron treatment, TIBC is not a measure of Trf concentration in neonatal piglets two days after birth. At day 8 of their life a high correlation coefficient of these two parameters was established in non-treated animals, while in iron-treated piglets the same correlation was established 12 days after iron treatment. Thus, we suggest that in neonatal piglets, TIBC could be used as a measure of Trf concentration only 12 days after i.m. iron treatment

The purpose of the study was to evaluate the hemostatic effectiveness of fibrin glue (FG) prepared by a modification of cryoprecipitation technique in experimental rat liver surgery. FG component 1 was prepared by triple or 'recycled' cryoprecipitation method from single-donor plasma. Rats subjected to liver incision, partial and total lobectomy were treated with FG on the surgical cut surface or underwent standard surgical technique. The efficacy of FG-treatment was evaluated on the basis of the 24-hour survival ratio and peripheral blood hematological parameters. The mean values of fibrinogen, FXIII, fibronectin and horizontal tensile strength of FG were 54.2 +/- 19.9 g/l, 13.5 +/- 3.6 IU/ml, 3103.1 +/- 148.9 mg/l, and 1.076 +/- 0.18 N/cm2, respectively. The survival of FG-treated rats subjected to partial and total lobectomy was significantly higher in comparison to the FG-nontreated animals, accompanied with higher values of red blood cell counts, hemoglobin concentration and hematocrit. When liver incision was performed, although there were no differences in survival rate, FG-treated animals had significantly higher values of the tested hematological parameters. The presented results demonstrated that by using 'recycled' cryoprecipitation it is possible to obtain high quality single-donor FG with successful hemostatic therapeutical effects, as confirmed in the experimental rat model of liver surgery.