No abstract available.
Diagnosis* ; Prostate* ; Prostatic Neoplasms* ; Ultrasonography*

A hyaluronic acid (HA) incorporated porous collagen matrix was fabricated at -70 degree C by lyophilization. The HA incorporated collagen matrix showed increased pore size in comparison with collagen matrix. Biodegradability and mechanical properties of matrices were controllable by varying the ultraviolet (UV) irradiation time for cross-linking collagen molecules. Addition of HA to collagen matrix did not effect ultimate tensile stress after UV irradiation. HA incorporated collagen matrices demonstrated a higher resistance against the collagenase degradation than collagen matrix. In an in vitro investigation of cellular behavior using dermal fibroblasts on the porous matrix, HA incorporated collagen matrix induced increased dermal fibroblast migration and proliferation in comparison with collagen matrix. These results suggest that the HA incorporated collagen porous matrix assumes to enhance dermal fibroblast adaptation and regenerative potential.
Collagen/*metabolism ; Extracellular Matrix/*metabolism ; Fibroblasts/*physiology ; Human ; Hyaluronic Acid/*metabolism ; Porosity

No abstract available.
Lithotripsy* ; Shock* ; Ureter* ; Ureteroscopy*

Intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) are weakly expressed in normal glomerular cells and vascular endothelial cells, but not in tubules. Granzyme B is a cytotoxic granule present in activated cytotoxic T cells and natural killer cells. To determine the effect of ICAM-1 and VCAM-1 expression and granzyme B-positive cells on histologic grade of rejection, we performed the immunohistochemical study on 19 renal biopsy specimens and one nephrectomy specimen from 14 patients with acute renal allograft rejection using monoclonal antibodies against theses proteins. According to severity of rejection based on Banff classification, three biopsies were classified as borderline, 4 grade I, 12 grade II, and 1 grade III. In all the cases with acute rejection, ICAM-1 and VCAM-1 were expressed in the tubular epithelial cells. The numerical score of ICAM-1 in the tubular epithelial cells was 1.0 in borderline cases, 1.3 0.4 in grade I cases, 2.2 0.8 in grade II cases, and 3.0 in grade III case. The staining intensity of ICAM-1 in the tubular epithelial cells was increased in accordance with histologic rejection grade (P<0.05). The staining intensity of ICAM-1 and VCAM-1 in the renal tubular epithelial cells was increased in accordance with the number of T lymphocytes in the renal parenchyme (r=0.46; P<0.05, r=0.61; P<0.01). The number of granzyme B-positive cells was 6.4 1.6/HPF in borderline cases, 8.1 2.5 in grade I cases, 19.6 11.7 in grade II cases, and 53 in grade III case. The number of T lymphocytes and granzyme B-positive cells was also increased in accordance with histologic rejection grade (P<0.05). These results suggest that ICAM-1 and granzyme B-positive cells may play an important role in the induction of renal allograft rejection and that the grading of severity of these parameters may be useful to predict the prognosis of renal allograft.
Allografts* ; Antibodies, Monoclonal ; Biopsy ; Classification ; Endothelial Cells ; Epithelial Cells ; Granzymes* ; Humans ; Intercellular Adhesion Molecule-1 ; Killer Cells, Natural ; Nephrectomy ; Prognosis ; T-Lymphocytes ; Vascular Cell Adhesion Molecule-1

The effects of centrifugal force on growth and differentiation of osteoblastic cells cultured in alpha-MEM containing 1% Fetal bovine serum were investigated by assays of DNA synthesis, alkaline phosphatase activity and osteocalcin- production in osteoblastic MC3T3-E1 cells. Centrifugation of the cells in low concentrations (1%) of fetal bovine serum caused a 1.9-fold increase of [3H] thymidine incorporation on day 3 from the start of centrifugation, and gradually decreased with culture up to day 9. Alkaline phosphatase activity was not affected by centrifugal force until day 5, and increased rapidly after day 7. Stimulation of DNA synthesis by centrifugation was abolished in the presence of H-7, an inhibitor of protein kinase C. These results suggest that centrifugal force stimulates the proliferation of osteoblastic cells through an autocrine secretion of some diffusable growth- promoting activity. Additional centrifugation of the cells also slightly stimulated alkaline phosphatase activity, although this did not directly influence the cell's osteocalcin-production activity.
Alkaline Phosphatase/metabolism ; Animal ; Cell Division ; Cells, Cultured ; Centrifugation ; DNA/biosynthesis ; Mice ; Osteoblasts/*physiology ; Stress, Mechanical

Preclinical evaluation of medical devices (prototype products) offers the opportunity to investigate and study the intended use of device materials. Preclinical evaluation programs are designed to determine the efficacy, safety, and biocompatibility of biomaterials, prostheses, and medical devices. The purpose of safety testing is to determine if a material presents potential harm to the human; it evaluates the interaction of the material with the in vivo environment and determines the effect of the host on the implant. Preclinical evaluation is the determination of the ability of the prototype product to perform with appropriate host response in a specific application, considered from the perspective of human clinical use. Therefore, preclinical data should include materials science and engineering, biology, biochemistry, medicine, host reactions and their evaluation, the testing of biomaterials, and the degradation of materials in a biological environment.
Animal ; Carcinogenicity Tests ; Equipment and Supplies*/adverse effects ; Hemolysis ; Human ; Pyrogens/toxicity ; Sterilization

It has recently been reported that bone marrow-derived mesenchymal stem cells (MSCs), which are systemically administrated to different species, undergo site-specific differentiation. This suggests that the tissue specific cells may cause or promote the differentiation of the MSCs toward their cell type via a cell-to-cell interaction that is mediated not only by hormones and cytokines, but also by direct cell-to-cell contact. In this study, in order to assess the possible synergistic interactions for osteogenesis between the two types of cells, the MSCs derived from rabbit bone marrow were co-cultured with rat calvarial osteoblasts in direct cell-to-cell contact in a control medium (CM) and in an osteogenic medium (OM). The cell number, alkaline phosphatase activity, and amount of calcium deposition were assayed in the cultures of MSCs, osteoblasts, and co-cultures of them in either OM or CM for up to 40 days. The cell numbers and the alkaline phosphatase activities in the co-culture were somewhere in between those of the osteoblast cultures and the MSC cultures. The amounts of deposited calcium were lower in the co-culture compared to those of the other cultures. This suggests that there are little synergistic interactions during osteogenesis in vitro between the rat osteoblasts and rabbit MSCs.
Alkaline Phosphatase/metabolism ; Animals ; Calcification, Physiologic ; *Cell Communication ; Cell Count ; Cell Differentiation ; Cell Division ; Female ; Mesoderm/*cytology ; Osteoblasts/*physiology ; *Osteogenesis ; Rabbits ; Stem Cells/*physiology

To determine applicability of the cryopreservation procedure for vessel grafts, the viability of endothelial cells (ECs) among the whole cells in three kinds of organs artery, vein, trachea in mongrel dogs was evaluated on the basis of histological analysis. The Griffonia simplicifolia agglutins-fluorescein isothiocyanate (GSA-FITC) and propidium iodide (PI) double staining methods were combined with flow cytometry (FCM), which was able to simultaneously determine the viability of whole cells and ECs from the same tissue, were performed after harvesting, after antibiotic solution treatment, and after cryopreservation and thawing. In most cases, the viability of ECs is lower than that of whole cells from veins and arteries. The viability of whole cells in veins was maintained until the antibiotic solution treatment and then decreased significantly after cryopreservation and thawing, while the ECs began to decrease significantly after the antibiotic solution treatment and more markedly decreased after thawing. The viability of ECs and whole cells from arteries was similar to that of the veins' conditions. The viability of whole cells from the trachea decreased with a similar pattern to that of the ECs from vessels. In consideration of maintaining cell viability among the three kinds of organs, the viability of arteries was better than that of the others. The cells in the trachea demonstrated a lower viability than the vessels. The effect of antibiotic solution treatment on the reduction of cell viability depends on the treatment time and temperature.
Animalt ; Arteries/transplantation ; Cell Survival ; Coronary Vessels*/transplantatione ; Cryopreservation* ; Dogs ; Endothelium, Vascular/physiology* ; Endothelium, Vascular/cytology ; Female ; Male ; Trachea*/transplantation ; Middle Age ; Veins/transplantation

A porcine heart valve was irradiated by Ultraviolet (UV) rays (10 W, 254 nm) for 2, 4, 8 and 24 hours at 4 degrees C to cross-link the structural collagen matrix. The degree of cross-linking was evaluated by assaying the released amount of hydroxyproline (Hyp) from the matrix, and comparing it with the positive controls of valves treated by glutaraldehyde (GA) solution (0.625 wt%) and the negative controls of non-treated fresh valves. The undigested weight ratio of the specimens increased by increasing the UV irradiation time. The undigested weight of the leaflets, tunica interna and tunica externa of the fresh, GA-treated and UV-irradiated specimens after collagenase digestion was compared. As UV irradiation increased, the amount of released hydroxyproline was gradually decreased until 8 hours of irradiation, after which the released hydroxyproline-reduction occurred slightly until 24 hours of irradiation time in this system. A total 47.68% of the hydroxyproline in the valve was cross-linked by UV irradiation after 24 hours, while 73.74% of the hydroxyproline in the positive control was crossed-linked. Light microscopic observation revealed that the typical crimp pattern of collagen fibers decreased and was rearranged into a dense flattened pattern as the UV irradiation induced interfibrilar cross-linking. GA-treated valves demonstrated a denser matrix pattern than the UV-irradiated specimens. Cross-linked collagenous tissue prepared by UV irradiation would be useful for improving durability and reducing the disadvantages related to using a chemical cross-linking agent.
Animal ; Aortic Valve/radiation effects* ; Aortic Valve/metabolism* ; Collagen/radiation effects* ; Collagen/chemistry* ; Hydroxyproline/metabolism ; Swine ; Ultraviolet Rays*

Collagen-based membranous materials of various shapes (gel, film, sponge) are known to be the most promising materials in terms of facilitating the regeneration of dermal defects. In this study, dense and porous collagen membranes were fabricated using air-drying and freeze-drying processes, respectively, and the effect of ultraviolet (UV) radiation on the degree of membrane crosslinking was evaluated by in vitro biodegradation and mechanical testing. A non-irradiated membrane group was used as the negative control and a glutaraldehyde (GA) treated group as the positive control. Scanning electron microscopy showed that, as the freezing temperature decreased to -196 degrees C, the resultant mean pore sizes also decreased; optimal pore size was obtained at a freezing temperature of -70 degrees C. In vitro biodegradation and mechanical testing demonstrated that GA treatment or 4 hours of exposure to UV radiation significantly increased both resistance to collagenase and mechanical strength versus the untreated controls, regardless of the collagen membrane type (dense or porous). Our results suggest that UV treatment is a useful tool for the fabrication of collagen membranes designed to be used as dermal dressings.
Animal ; Cattle ; Collagen/ultrastructure ; Collagen/radiation effects* ; Collagen/metabolism ; Elasticity ; Membranes, Artificial* ; Microscopy, Electron, Scanning ; Porosity ; Tensile Strength ; Ultraviolet Rays*