The matrix metalloproteinases (MMPs) play a key role in the normal physiology of connective tissue during development, morphogenesis, and wound healing. Dysregulation of their activity has been implicated in numerous diseases including encephalopathy and the process of bone loss. Thus, MMPs may play a role in the encephalopathy and post-transplantation bone disease by immunosuppressive drugs such as cyclosporine (CsA) and tacrolimus. Gelatin zymography of MMP-9 and MMP-2 was performed in the glioma cells and osteoblast after CsA or tacrolimus treatment. Glioma cells or rat osteoblast ROS17/2.8 cells were treated with CsA or tacrolimus to make final concentration from 2 to 250 µM. After incubation, gelatin zymography of MMP-9 and MMP-2 was performed. And the density for the MMP bands were measured using luminescent image analyzer system. Both MMP-9 and MMP-2 activities in the osteoblast cells were decreased depending on the concentration of CsA or tacrolimus. MMP-2 activity was increased after CsA or tacrolimus treatment in the glioma cells. However, MMP-9 activities were decreased after CsA or tacrolimus treatment in the glioma cells. These results indicate that dysregulation of MMPs in the osteoblast and in the glioma cells by immunosuppressive drugs may one of the contributing factors in post-transplantation bone disease and in the encephalopathy by tacrolimus or cyclosporine.
Animals ; Bone Diseases ; Connective Tissue ; Cyclosporine ; Gelatin ; Glioma* ; Matrix Metalloproteinases ; Morphogenesis ; Osteoblasts* ; Physiology ; Rats ; Tacrolimus ; Wound Healing

PURPOSE: We tested the effect of team-based learning (TBL) on medical education through the second-year premedical students’ TBL scores in biochemistry classes over 5 years. METHODS: We analyzed the results based on test scores before and after the students’ debate. The groups of students for statistical analysis were divided as follows: group 1 comprised the top-ranked students, group 3 comprised the low-ranked students, and group 2 comprised the medium-ranked students. Therefore, group T comprised 382 students (the total number of students in group 1, 2, and 3). To calibrate the difficulty of the test, original scores were converted into standardized scores. We determined the differences of the tests using Student t-test, and the relationship between scores before, and after the TBL using linear regression tests. RESULTS: Although there was a decrease in the lowest score, group T and 3 showed a significant increase in both original and standardized scores; there was also an increase in the standardized score of group 3. There was a positive correlation between the pre- and the post-debate scores in group T, and 2. And the beta values of the pre-debate scores and “the changes between the pre- and post-debate scores” were statistically significant in both original and standardized scores. CONCLUSION: TBL is one of the educational methods for helping students improve their grades, particularly those of low-ranked students.
Biochemistry* ; Education, Medical ; Education, Premedical ; Humans ; Learning* ; Linear Models ; Schools, Medical

Hemolysis is one of the side effects of cyclosporine(CsA). Some experimental and clinical data have strongly suggested that CsA-induced hemolysis is resulted from the increased production of free radical species by CsA. Melatonin, a pineal secretory product, acts as a highly efficient free radical scavenger. Thus, melatonin may have a protective effect on the CsA-induced hemolysis. To test this hypothesis, the final concentration of 4.2x106/mL with human erythrocytes was incubated in test tube at 37 degrees C water bath with 1.67 mg/mL of CsA and 72 nmol/mL of melatonin. The degree of hemolysis and the amount of malondialdehyde which gives an indirect index of oxidative injury were measured in group 1 containing only isotonic buffer solution, in group 2 containing only CsA, and in group 3 containing both CsA and melatonin. The degrees of hemolysis in group 2 were higher than those of group 1. The degrees of hemolysis in group 3 were higher than those of group 1, and lower than those of group 2. The amounts of malondialdehyde in group 2 were higher than those of group 1. The amounts of malondialdehyde in group 3 were higher than those of group 1, and lower than those of group 2. These results indicate that the direct contact of erythrocytes with CsA results in free radical mediated hemolysis and the hemolysis by CsA can be prevented with melatonin.
Humans

No abstract available.
Addison Disease*

Suppressed superoxide dismutase activity, which is responsible for the dismutation of superoxide anion to hydrogen peroxide, is known to be one of the factors leading to lipid peroxidation in the erythrocyte membrane structures in the patients with end stage renal disease. In this study, copper and zinc levels were determined in the erythrocytes and plasma from 14 hemodialysis patients to explain the decreased activity of superoxide dismutase in erythrocytes. Before dialysis, superoxide dismutase, copper and zinc levels in erythrocytes were lower than those from healthy controls. Superoxide dismutase activity was normalized perfectly after hemodialysis. Copper level in the erythrocytes was normalized after hemodialysis, but its level was still lower than that in healthy controls. Zinc level in the erythrocytes was not changed after hemodialysis. Before hemodialysis, copper and zinc levels in plasma were higher than those from healthy controls. Copper level in the plasma was higher after hemodialysis than before hemodialysis. Zinc level in the plasma was not changed after hemodialysis. It is suggested that copper levels in erythrocytes from patients with hemodialysis affects partially to the superoxide dismutase activity, and superoxide dismutase activity is influenced more by copper levels than by zinc levels during hemodialysis.
Copper ; Dialysis ; Erythrocyte Membrane ; Erythrocytes* ; Humans ; Hydrogen Peroxide ; Kidney Failure, Chronic* ; Lipid Peroxidation ; Plasma ; Renal Dialysis ; Superoxide Dismutase* ; Superoxides* ; Zinc

Proteins are known to be carbamylated as a result of reactions with ureaderived cyanate. We investigated the effect of carbamylation by cyanate on the catalase activity which is known that its decreased activity contributes to cataract formation, and on the lens protein. Catalase and lens protein were carbamylated by incubation with cyanate at 37degrees C. The extent of carbamylation was monitored by following the loss of free amino group using trinitrobenzenesulphonic acid. The level of carbamylated protein was 76% in patients with cataract. Carbamylated proteins in normal lens from rabbits and carbamylated catalase were increased as the time of exposure to cyanate activity. Our results suggest that cyanate is an inhibitor of catalase, and carbamylation of catalase as a result of reaction with ureaderived cyanate may contribute to cataract formation.
Catalase* ; Cataract ; Humans ; Rabbits

To clarify the mechanism of the protective effect of hemodialysis on lipid peroxidation in RBC membrane structures, the level of malondialdehyde (MDA) which is the lipid peroxidation product, and the activities of antioxidant enzymes such as superoxide dismutase (SOD), catalase, and glutathione peroxidase (GSH-Px) were determined before and after hemodialysis in the RBCs from 20 patients with end stage renal disease (ESRD), and from 14 healthy subjects. Before dialysis, MDA levels in the RBCs from the patients with ESRD were higher than those from healthy controls. SOD and catalase activities in the RBCs were lower. After hemodialysis, MDA, SOD, and catalase in the RBCs from the patients with ESRD were normalized. These results indicate that hemodialysis treatment is helpful to protect the peroxidative darnage through normalizing the activities of antioxidant enzymes.
Catalase ; Dialysis ; Erythrocytes* ; Glutathione Peroxidase ; Humans ; Kidney Failure, Chronic* ; Lipid Peroxidation ; Malondialdehyde* ; Membranes ; Renal Dialysis* ; Superoxide Dismutase

During simulated weightlessness and spaceflight, variations in plasma and urinary catecholamine(GA) levels haute been observed. The alterations of metabolism of CA In liver, the main site of metabolism, ate yet not known We measured the activity of catechol-O-methyl transferase (COMT) and monoamine oxidase (MAO) In rat liver as Indicators of CA metabolism before and during head-down suspension The rats were placed In a -45 degress antiorthostatic position for 2 weeks. Head-down suspension resulted In decrease other hepatic MAO B activity By contrast, the activities of other hepatic degrading enzymes, COMT and MAO A, did not altered These findings Indicate that a prolonged exposure to simulated weightlessness exerts no remarkable effect on CA degradation in rat liver.
Animals ; Liver* ; Metabolism ; Monoamine Oxidase ; Plasma ; Rats* ; Space Flight ; Transferases ; Weightlessness

Ossifying fibroma is not a well recognized entity, and only rarely affects the long bones. The main differential diagnosis is with fibrous dysplasia and with adamantinoma, non-ossifying fibroma of the long bone. Ossifying fibroma seldom has even a moderate tendency to progress during childhood, but it recurs frequently after curettage or subperiosteal resection. Any progression of the lesion comes to an end after puberty. So, surgery should be delayed as long as possible. But, if the lesion is rapidly progressive, or if a patient has repeated fractures, it would be necessary to resort to wide extraperiosteal resection. We have experienced 7 cases of ossifying fibroma from Octover 1979 to November 1988. The results were as follows; 1. The male and female ratio, was 5 to 2 and six patients were at their first decade, and one patient was 13 years old. 2. The lesion site was six cases in the tibia, one case in the fibula. 3. In six patients, we had done wide resection with free-vasculaized fibular graft in five cases and wide resection of the distal one-third of the fibula in one case. Two patients among them had recurrence. One case of recurrence was performed incomplete wide resection with free vascularized fibular graft because the lesion was too close to the distal epiphysis of the tibia.
Adamantinoma ; Adolescent ; Curettage ; Diagnosis, Differential ; Epiphyses ; Female ; Fibroma ; Fibroma, Ossifying ; Fibula ; Health Resorts ; Humans ; Male ; Puberty ; Recurrence ; Tibia ; Transplants

No abstract available.
Korea*