Objective: : Biodegradable poly-L-lactic acid (PLLA) with a highly biocompatible surface via tantalum (Ta) ion implantation can be an innovative solution for the problems associated with current biodegradable stents. The purpose of this study is to develop a Ta-implanted PLLA stent for clinical use and to investigate its biological performance capabilities. Methods: : A series of in vitro and in vivo tests were used to assess the biological performance of bare and Ta-implanted PLLA stents. The re-endothelialization ability and thrombogenicity were examined through in vitro endothelial cell and platelet adhesion tests. An in vivo swine model was used to evaluate the effects of Ta ion implantation on subacute restenosis and thrombosis. Angiographic and histologic evaluations were conducted at one, two and three months post-treatment. Results: : The Ta-implanted PLLA stent was successfully fabricated, exhibiting a smooth surface morphology and modified layer integration. After Ta ion implantation, the surface properties were more favorable for rapid endothelialization and for less platelet attachment compared to the bare PLLA stent. In an in vivo animal test, follow-up angiography showed no evidence of in-stent stenosis in either group. In a microscopic histologic examination, luminal thrombus formation was significantly suppressed in the Ta-implanted PLLA stent group according to the 2-month follow-up assessment (21.2% vs. 63.9%, p=0.005). Cells positive for CD 68, a marker for the monocyte lineage, were less frequently identified around the Ta-implanted PLLA stent in the 1-month follow-up assessments. Conclusion : The use of a Ta-implanted PLLA stent appears to promote re-endothelialization and anti-thrombogenicity.

Hydroxyapatite(HA) has been extensively used as bone graft materials and tooth implant surface coating materials because of its biocompatibility and osteoconductive properties. However, as HA is intrinsically poor in mechanical properties, zirconia(ZrO2) was incorporated with HA as reinforcing phases for improvement of mechanical properties. The purpose of this study was to investigate the biological activities of HA-coated zirconia through the cell proliferation test, measurements of alkaline phosphatase activity, and histologic examination. Four kinds of tested blocks were prepared according to the pore size (300-500micrometer/500-700micrometer) and the porosity (70%/90%). Cell proliferation and alkaline phosphatase activity was measured at 1, 7, 14 days. The number of cells proliferate after 7, 14 days were significantly increased in all groups when compared with that of the first day, but there was no significant difference between the 4 groups at each time period. At the 7 day, alkaline phosphatase activities of cells cultured in 4 groups were higher than that of the first day, but there was no significant difference between the 4 groups at each time period. The human gingival fibroblast and MG 63 cell was used to evaluate the cell cytotoxicity using MTT test. The materials tested in the current study turned out to be non-cytotoxic. In histologic examination(SEM), at 1 day there were many cells attached on the surfaces of all kinds of tested blocks. The number of cells were increased over time. At the 14 day, there were more cells proliferated than 1 day and some of the pores of blocks were partially filled with the proliferated cells. The in vitro response of osteoblast-like cells to the HA-coated zirconia showed comparable effect on transformation comparable to hydroxyapatite.
Alkaline Phosphatase ; Bone Regeneration ; Cell Proliferation ; Durapatite ; Fibroblasts ; Humans ; Porosity ; Tooth ; Transplants

There are many possible causes of esophageal ulcer, such as reflux esophagitis, pill-induced esophagitis, infectious esophagitis, tuberculosis, syphilis, Behcet's disease, radiation injury, caustic injury, foreign body-induced injury, esophageal cancer, and so on. However, there are only a few cases of esophageal ulcer by thermal injury from food, and most of these were caused by liquids; few are related to ingestion of solid food. We experienced a case of a large symmetrical esophageal ulcer caused by thermal and compressive injury from a hot solid foodstuff known as 'Song-pyen', a traditional Korean food, and report the natural course of healing by conservative treatment, with a review of the few available reports regarding such injuries.
Eating ; Esophageal Neoplasms ; Esophagitis ; Esophagitis, Peptic ; Radiation Injuries ; Syphilis ; Tuberculosis ; Ulcer

OBJECTIVE: Bucillamine is a disease-modifying antirheumatic drug that's widely used in Korea and Japan, and it is reported to be a cause of proteinuria. However, the clinical course of the nephropathy associated with the use of bucillamine in rheumatoid arthritis patients has not been described in detail in Korea. METHODS: We examined clinical records of 835 patients who were treated with bucillamine for rheumatoid arthritis at least 2 months at Ajou University Hospital from 2003 to 2008, and we found 23 patients (2.75%) with proteinuria. Each patient was followed up until the proteinuria had resolved. RESULTS: At the time the proteinuria developed, the mean age of patients was 53.8+/-11.0 years. Only one patient had marked hypoalbuminemia (<3.0 g/dL). The mean value of the random urine protein-creatinine ratio was 3.44+/-2.99. The proteinuria appeared 4~18 months after the initiation of the treatment with bucillamine. Among the patients, renal biopsy was carried out in 18 patients, and pathological findings were 17 cases of membranous glomerulopathy and 1 case of focal segmental glomerulosclerosis. On the follow-up of the 18 patients, the proteinuria in all the patients had resolved completely without deterioration of renal function. But the time to resolution of the proteinuria was positively correlated with the length of bucillamine treatment after the onset of proteinuria (p<0.001, r=0.744). CONCLUSION: Prevalence of proteinuria in patients receiving bucillamine was 2.75%, and bucillamine-induced nephropathy showed a good prognosis in Korea. The most important thing for resolving the bucillamine-induced proteinuria is to discontinue the bucillamine.
Arthritis, Rheumatoid ; Biopsy ; Cysteine ; Follow-Up Studies ; Glomerulonephritis, Membranous ; Glomerulosclerosis, Focal Segmental ; Humans ; Hypoalbuminemia ; Japan ; Korea ; Prevalence ; Prognosis ; Proteinuria

Systemic lupus erythematosus (SLE) is a typical autoimmune disease that's characterized by various autoantibodies to nuclear and cytoplasmic antigens. The presence of antinuclear antibodies (ANA) in serum is generally considered a decisive diagnostic sign of SLE. However, a small subset of SLE patients who had the typical clinical features of SLE was reported to show persistently negative ANA tests. Our report describes a 16-yr-old female who presented with the clinical manifestations of SLE such as malar rash, photosensitivity, arthritis, lymphopenia, pericarditis and proteinuria. The serum autoantibodies were all negative and renal biopsy showed that the histopathological changes of immune complex mediated the focal segmental necrotizing glomerulonephritis with crescent formation. She was treated with monthly pulse cyclophosphamide along with corticosteroids. During the 2-yr follow-up period, the proteinuria was markedly decreased and all of the ANA and anti-double stranded DNA antibody tests were negative. This case suggests that ANA may not be required in the pathogenesis of lupus nephritis.
Adolescent ; Antibodies, Antinuclear/*immunology ; Biopsy ; Female ; Follow-Up Studies ; Humans ; Lupus Nephritis/diagnosis/*immunology ; Tomography, X-Ray Computed

It is known that rheumatoid arthritis (RA) patients show increased incidence of multiple myeloma (MM), despite its rarity. Only one case of MM with seronegative RA was reported in Korea, thus far. We report a case of MM with seropositive RA. The patient was a 66 year old female who had been diagnosed with seropositive RA 4 years ago. Over the last 1 month, the patient experienced general weakness and weight loss of 10 kg. It was found that her serum creatinine had increased and her urine analysis showed proteinuria. To evaluate renal failure and proteinuria, renal biopsy, bone marrow biopsy and electrophoresis were carried out. A diagnosis of myeloma cast nephropathy was made. We report this rare case of MM represented as acute renal failure during the treatment for RA, and include a review of the literature.
Acute Kidney Injury* ; Arthritis, Rheumatoid* ; Biopsy ; Bone Marrow ; Creatinine ; Diagnosis ; Electrophoresis ; Female ; Humans ; Incidence ; Korea ; Multiple Myeloma* ; Proteinuria ; Renal Insufficiency ; Weight Loss