Analysis of glycosaminoglycans in rabbit cornea after excimer laser keratectomy

BACKGROUND/AIMS: The biochemical basis for the development of subepithelial opacity of the cornea after excimer laser keratectomy has yet to be fully defined. The aim of this study was to evaluate the alterations of glycosaminoglycans (GAGs) after excimer laser keratectomy. METHODS: Rabbit corneas were harvested on days 5, 10, 20, and 30 after excimer laser photoablation. The amount of main disaccharide units was determined by high performance liquid chromatography (HPLC). In addition, immunohistochemical studies were performed on corneal sections 20 days after the ablation. RESULTS: The concentrations of DeltaDi-0S at 5 and 10 days were significantly lower than before the ablation. DeltaDi-6S showed a significant increase 5 days after the ablation but DeltaDi-4S did not show any significant change. There was a significant increase in DeltaDi-HA at 20 and 30 days after ablation. In immunohistochemistry, the positive staining for DeltaDi-6S and hyaluronic acid was observed in the subepithelial region. These immunohistochemical results were well correlated with the HPLC findings. CONCLUSIONS: The increase in chondroitin-6 sulphate and hyaluronic acid may be related to corneal subepithelial opacity after excimer laser keratectomy.     

Primary dermal and eye irritability tests of hydrophobically modified hydroxypropyl methylcellulose in rabbits.

Primary dermal and eye irritation tests of hydrophobically modified hydroxypropyl methylcellulose (HM-HPMC, hydroxypropyl methylcellulose modified with stearylglycidylether), a new cellulose derivative used as a thickener for topical pharmaceuticals and cosmetics, were conducted in rabbits. A dispersion of HM-HPMC (3%) was applied to intact and abraded skins and reactions were observed. A very slight erythema was observed in both skins and this polymer was categorized as a "mild irritant". In the eye irritation test, with a dispersion of the same concentration, it was categorized as "marginal" in unrinsed eyes and "negative" in rinsed eyes.     

Two cases of asymptomatic epiglottic cyst confirmed by lateral cervical roentgenogram

Key words  complications - intubation - epiglottic cyst     

Primary thymic adenocarcinoma coexisting with type AB thymoma: a rare case with long-term survival

Thymic carcinoma is a rare tumor. The most common histological subtype is squamous cell carcinoma, and only a few cases of thymic adenocarcinoma have been reported. A case of papillary adenocarcinoma of thymic origin that coexisted with type AB thymoma as a separate nodule is presented herein. The patient was found to have an abnormal mediastinal shadow on chest X-ray. A computed tomography scan revealed a round, 6.5-cm-diameter mass in the right anterior mediastinum. The preoperative diagnosis was thymoma, and thymothymectomy was performed. On pathological examination, two tumors, which were diagnosed as papillary adenocarcinoma and type AB thymoma, respectively, were present in the thymus without any connection with each other. The patient has been alive without any signs of recurrence for 11 years after surgery. We diagnosed the adenocarcinoma in this case was a primary thymic carcinoma.     

Neutralization of blood group A-antigen by a novel anti-A antibody: overcoming ABO-incompatible solid-organ transplantation

BACKGROUND: The major barrier to ABO-incompatible solid-organ transplantation is acute humoral rejection. It is known to be triggered by antidonor blood group A/B antibodies, which might bind to A/B-antigen on the endothelium of the graft. Various strategies to reduce antiblood group antibody by overcoming ABO-incompatible transplantation have been tried. However, antigen-suppressing procedures have not been performed. METHODS: We produced a novel anti-A antibody (K7508) by immunizing mice with salivary mucin of a blood group A individual, thereby clarifying that blood group A-antigen is expressed in endothelial cells of the liver. We investigated whether K7508 can mask A-antigen on the cells in vitro. Next, we immunized mice with A-antigen-expressing cells coated with K7508 or its Fab fragment, and measured anti-A antibody production in the mice. RESULTS: Blood group A-antigen-expressing cells, such as blood group A-red blood cells (A-RBCs) and A431 cells, coated with K7508 were not recognized by another anti-A antibody in flow cytometry, indicating that A-antigen was masked by K7508 in vitro. The A-antigen on the paraffin-embedded liver tissue was also masked by K7508. Furthermore, the production of anti-A antibody in mice immunized with A-antigen-expressing cells coated with K7508 or its Fab fragment was significantly suppressed compared to that in mice immunized with non-coated cells alone, indicating that A-antigen was neutralized by K7508 in vivo. CONCLUSIONS: The neutralization of blood group antigen by antiblood group antibody and especially its Fab fragment might represent one strategy to overcome ABO-incompatible organ transplantation.     

Cuffed anastomosis for above-knee femoropopliteal bypass with a stretch expanded polytetrafluoroethylene graft

PURPOSE: To evaluate the patency and limb-salvage rates associated with cuffed anastomosis in above-knee femoropopliteal (FP) bypasses using prosthetic grafts. METHODS: Between January 1997 and December 2005, 96 patients (99 limbs) underwent above-knee FP bypass grafting for peripheral vascular disease, with disabling claudication in 81%. All grafts were 6-mm, thin-walled, ringed, expanded polytetrafluoroethylene (ePTFE) stretch grafts anastomosed to the above-knee segment of the popliteal artery in an end-to-side fashion, with a protruding area created around the anastomotic toe and an angle of less than 30 degrees between the graft and the artery. Postoperatively, graft patency was monitored by several objective methods. Patency and limb-salvage rates were calculated by actuarial methods and Kaplan-Meier analysis. RESULTS: The mean follow-up period was 40.4 months; 15 patients were lost to follow-up. The 1-, 3-, and 5-year primary graft patency rates were 94.5%, 88.2%, and 85.7%, respectively. The 1-, 3-, and 5-year secondary patency rates were 95.6%, 94.1%, and 90.8%. The 1-, 3-, and 5-year limb-salvage rates were 98.9%, 97.3%, and 97.3%. There were three graft infections. CONCLUSION: The use of a cuffed anastomosis in FP bypass with an ePTFE stretch prosthesis appears to increase graft patency rates.     

The role of graft and host accommodation in a hamster-to-rat cardiac transplantation model

BACKGROUND: We evaluated the importance and mechanism of graft and host accommodation in hamster-to-rat cardiac xenotransplantation models. METHODS: To evaluate graft accommodation, accommodated hamster grafts (Group 2) were transplanted to na?ve host rats treated with FK506, and compared with na?ve hamster grafts (Group 1). To evaluate host accommodation, three groups were evaluated: naive hamster hearts were transplanted to na?ve hosts treated with FK506 (Group 3: 0.5 mg/kg, Group 4: 1.0 mg/kg) and splenectomy, and compared with accommodating hosts (Group 5) with FK506 0.5 mg/kg and splenectomy. We examined graft survival, histopathology, antihamster antibodies and B-1 cells in blood. RESULTS: Graft survival in Group 2 (3.4+/-0.9 days) was not significantly different from that in Group 1 (2.8+/-0.4 days). Graft survival in Groups 4 and 5 (>30 days) was significantly prolonged compared with that in Group 3 (6.0+/-0.7 days). Histopathology of Groups 1-3 showed humoral rejection, whereas Groups 4 and 5 showed normal histology and expression of protective genes. In Groups 1-3, antihamster immunoglobulin (Ig) M and B-1 cells increased significantly compared to Groups 4 and 5, where IgM and B-1 cells remained low or were reduced. CONCLUSIONS: Host accommodation was more important than graft accommodation. Accommodating grafts expressing protective genes were rejected with an elevation of both IgM and B-1 cells. In accommodated hosts, both IgM and B-1 cells decreased, suggesting that B-1 cells may be responsible for the production of antihamster antibodies. These results suggest that sufficient suppression of B-1 cells, resulting in decreased titers of antihamster antibodies, may play an important role in host accommodation.     

Adult Bochdalek hernia with volvulus of the stomach

We report a rare case of Bochdalek hernia, congenital posterolateral diaphragmatic hernia with volvulus of the stomach, in an adult A 74-year-old man was admitted to our hospital complaining of sudden abdominal pain and vomiting. Roentgenologic examination of the chest showed air above the left diaphragm, and the mediastinum was displaced to the right. Upper gastrointestinal series revealed volvulus of the stomach in which the pylorus was displaced to the left. The surgical repair was done through left thoracotomy with combining laparoscopy and thoracoscopy without surgical complications, 1 year later the patient is asymptomatic.     

Reoperative coronary artery bypass grafting using a minimally invasive direct coronary artery bypass procedure

OBJECTIVE: Reoperative coronary artery bypass grafting with cardiopulmonary bypass tends to cause a higher mortality and morbidity than the primary operation. The purpose of this study was to discuss the effectiveness and safety of a minimally invasive coronary artery bypass procedure for patients who had previously undergone coronary artery bypass surgery. METHODS: We performed redo single coronary artery bypass grafting to the left anterior descending coronary artery in 9 patients and to the right coronary artery in 3 patients using minimally invasive cardiac surgery. The graft to the left anterior descending coronary artery was taken from the left internal thoracic artery in 5 patients, the right gastroepiploic artery in 3 patients, and from the saphenous vein in the other 1 patient. The graft to the right coronary artery was from the right gastroepiploic artery in all 3 patients. RESULTS: All grafts were patent. There was no major postoperative complication and no surgical or hospital death except one late death. CONCLUSIONS: In selected patients, we could safely and completely perform coronary artery bypass re-grafting to the left descending coronary artery or right coronary artery using a minimally invasive operation.     

Parathyroid hormone increases the expression level of matrix metalloproteinase-13 in vivo

Parathyroid hormone (PTH) increases serum calcium (Ca) by enhancing bone resorption and renal Ca reabsorption. However, detailed mechanisms of enhanced bone resorption by PTH remain to be elucidated. Although PTH has been shown to increase the expression level of osteoblastic matrix metalloproteinase (MMP)-13 in vitro, only limited results are available regarding the in vivo regulation of MMP expression. In the present study, we have examined expression levels of MMPs in PTH-infused rats. Infusion of 1.5 or 2.0 nmol/kg/day rat PTH(1–34) for 3 days resulted in a dose-dependent increase in serum Ca. PTH infusion also decreased serum phosphate levels and increased urinary excretion of Ca and phosphate. Infusion of PTH for 7 days resulted in less severe hypercalcemia and hypophosphatemia. Urinary Ca and phosphate excretion in rats infused for 7 days was less than that in rats infused for 3 days. Northern blot analysis showed that PTH infusion increased the expression level of MMP-13 in calvaria, although it did not affect MMP-2 expression. Furthermore, the time-course and severity of hypercalcemia and hypercalciuria correlated with the expression level of MMP-13. In situ hybridization also showed that PTH infusion increased the expression level of MMP-13 in femora. These results indicate that PTH enhances MMP-13 expression in vivo and suggest that PTH stimulates bone resorption at least partly by enhancing MMP-13 expression. Received: June 5, 2000 / Accepted: January 12, 2001