BACKGROUND: Traditionally, the treatment of a thrombosed dialysis access in hemodialysis patients in Korea has been primarily performed by vascular surgeons and interventional radiologists. The objective of this study was to evaluate the outcome of percutaneous thrombectomy procedures performed by an interventional nephrologist. METHODS: From October 2010 to May 2014, 75 consecutive percutaneous thrombectomies were performed on 42 patients treated with maintenance hemodialysis. All percutaneous thrombectomy procedures were performed by an interventional nephrologist in a single hospital in Jeju, Korea. The thrombosed arteriovenous graft and arteriovenous fistula were declotted by thromboaspiration mechanical thrombectomy or pharmacomechanical thrombolysis. Kaplan-Meier survival analysis was performed to analyze the primary and secondary patency after the initial successful thrombectomy. Success and complication rates were identified and compared with the recommendations of the Kidney Disease Dialysis Outcomes Quality Initiative (KDOQI) guideline. RESULTS: The overall clinical success rate was 89.3% (67/75). In the successful cases, the postintervention primary (unassisted) patency rates at 30 days, 90 days, and 180 days were 79.9%, 56.6%, and 25.6%, respectively. The secondary patency rates at 30 days, 90 days, and 180 days were 92.2%, 85.7%, and 83.7%, respectively. There were no major complications, and all complications were treated successfully during the procedure. CONCLUSION: The clinical success rate and primary patency rate at 3 months exceeded the recommendations of the KDOQI guideline, and were comparable to that of other reports. Percutaneous thrombectomy by an interventional nephrologist was safe and effective.
Angioplasty ; Arteriovenous Fistula ; Dialysis* ; Endovascular Procedures ; Humans ; Kidney Diseases ; Korea ; Renal Dialysis ; Thrombectomy* ; Thrombosis* ; Transplants

The purine antimetabolite 6-Mercaptopurine (6-MP) has been in clinical use for over 30 years and is still a widely used agent in the treatment of childhood acute lymphoblastic leukemia. The bioavailibility, clinical efficacy and toxicity of 6-MP administered orally for maintenance therapy of children with acute lymphoblastic leukemia are highly variable in many studies, as well as at differnt times in same patient. there are many factors affecting the bioavailibility of 6-MP. The most notably factor being that concomitantly administered drugs and foods might contribute to a decrease in the bioavailibity of this drug. In our sociocultural environment milk is a major constituent of child's foods. Cow's milk contains a high concentration of xanthine oxidase, which could potentially transform 6-TM into 6-thioxanthine (6-TX) and 6-thiouric acid (6-TUA) which have no more therapeutic effects. In this study, we evaluated the effect of various milk products on the bioavailability of 6-MP. Incubation at 37degrees C for 30 min raw or pasteurized milk resulted in transformation of a large quantity of clinically relevant concentration of 6-MP into 6-TUA. The concomitant adminstration of folic acid and allopurinol has markedly inhibitory effect on the 6-MP destroying activity of milk at clinically relevant concentrations. These observations may help to optimize modalities of administration of 6-MP for the treartment of patients with childhood leukemia.
6-Mercaptopurine* ; Allopurinol ; Biological Availability* ; Child ; Complement Factor B ; Folic Acid ; Humans ; Leukemia ; Milk* ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; Xanthine Oxidase

PURPOSE: Fibronectin (FN) has been shown to stimulate bone regeneration in animal models. The aim of this study was to evaluate the capacity of bovine bone mineral coated with synthetic oligopeptides to enhance bone regeneration in rabbit calvarial defects. METHODS: Oligopeptides including fibrin-binding sequences of FN repeats were synthesized on the basis of primary and tertiary human plasma FN structures. Peptide coated and uncoated bone minerals were implanted into 10 mm calvarial defects in New Zealand white rabbits, and the animals were sacrificed at 4 or 8 weeks after surgery. After specimens were prepared, histologic examination and histomorphometric analysis were performed. RESULTS: At 4 weeks after surgery, the uncoated groups showed a limited amount of osteoid formation at the periphery of the defect and the oligopeptide coated groups showed more osteoid formation and new bone formation in the center of the defect as well as at the periphery. At 8 weeks, both sites showed increased new bone formation. However, the difference between the two sites had reduced. CONCLUSIONS: Fibrin-binding synthetic oligopeptide derived from FN on deproteinized bovine bone enhanced new bone formation in rabbit calvarial defects at the early healing stage. This result suggests that these oligopeptides can be beneficial in reconstructing oral and maxillofacial deformities or in regenerating osseous bone defects.
Animals ; Bone Regeneration ; Congenital Abnormalities ; Fibrin ; Fibronectins ; Humans ; Minerals ; Models, Animal ; Oligopeptides ; Osteogenesis ; Plasma ; Rabbits

PURPOSE: To evaluate the radiologic findings of carotid-vertebrobasilar anastomosis and associated anomalies. MATERIALS AND METHODS: Thirteen patients with fourteen cases of carotid-vertebrobasilar anastomosis collectedfrom January 1992 to December 1997 were reviewed. Clinical diagnosis refered for cerebral angiography werecerebral infarction(n=3), intracranial hemorrhage(n=2), subarachnoid hemorrhage(n=1), brain tumor(n=3),arteriovenous malformation(n=3) and trigeminal neuralgia(n=1). Cerebral angiograms and clinical symptoms wereretrospectively analyzed. RESULTS: The fourteen carotid-vertebrobasilar anastomsis consisted of eleven cases ofpersistent trigeminal artery and three cases of type I proatantal intersegmental artery. Persistent trigeminalarteries were associated with anterior communicating artery aneurysm(n=1), posterior fossa arteriovenousmalformation(n=2) and persistent trigeminal artery variant(n=5). Type I proatantal intersegmental arteries wereassociated with hypoplastic vertebral arteries(n=2) : only proximal segment in one, and proximal and distalsegments in one case. Only one patient had clinical symptom related to the carotid-vertebrobasilar anastomosiswhich was trigeminal neuralgia. CONCLUSION: Knowledge of the anatomical and radiologic findings ofcarotid-vertebrobasilar anastomosis and associated anomalies will aid in the accurate diagnosis of neurovasculardisease and prevent possible complications during surgical and interventional procedures.
Arteries ; Brain ; Cerebral Angiography ; Diagnosis ; Humans ; Trigeminal Neuralgia

OBJECTIVE: The potassium disturbance associated with thiopental continuous infusion in neurosurgical patients is well known. However, the effect of propofol continuous infusion on serum potassium levels has not been investigated extensively. METHODS: We reviewed the medical records of 60 consecutive patients who received coma therapy or deep sedation for intracranial pressure control using either thiopental or propofol between January 2010 and January 2012. RESULTS: The overall incidence of hypokalemia (K<3.5 mmol/L) was comparable between thiopental and propofol groups (89.2% vs. 82.6%). But, the incidence of moderate to severe hypokalemia (K<3.0 mmol/L) was significantly higher in thiopental group (51.4% vs. 13.0%, p=0.003). The lowest potassium level (2.9 mmol/L vs. 3.2 mmol/L, p=0.020) was lower in thiopental group. The patients in the thiopental group required greater potassium replacement than the propofol group patients (0.08 mmol/kg/h vs. 0.02 mmol/kg/h, p<0.001). On multivariate analysis, thiopental [odds ratio, 95% confidence interval, 7.31 (1.78-27.81); p=0.005] was associated with moderate to severe hypokalemia during continuous infusion. The incidence of rebound hyperkalemia (K>5.0 mmol/L, 32.4% vs. 4.3%, p=0.010) and the peak potassium concentration (4.8 mmol/L vs. 4.2 mmol/L, p=0.037) after the cessation of therapy were higher in thiopental group. On multivariate analysis, thiopental [8.82 (1.00-77.81); p=0.049] and duration of continuous infusion [1.02 (1.00-1.04); p=0.016] were associated with rebound hyperkalemia once therapy was discontinued. CONCLUSION: Propofol was less frequently associated with moderate to severe hypokalemia after induction and rebound hyperkalemia following the cessation of continuous infusion than thiopental.
Coma ; Deep Sedation ; Humans ; Hyperkalemia ; Hypokalemia ; Incidence ; Intracranial Hypertension ; Intracranial Pressure ; Medical Records ; Multivariate Analysis ; Potassium* ; Propofol* ; Thiopental*

PURPOSE: Fibronectin(FN), one of the major components of ECM, mediates wide variety of cellular interactions including cell adhesion, migration, proliferation and differentiation. In this study, we used synthetic peptides based on fibrin binding sites of amino-terminal of FN and evaluated their biologic effects on periodontal ligament(PDL) cells. MATERIALS AND METHODS: PDL cells were cultured on synthetic oligopeptides coated dishes and examined for cell adhesion, proliferation via confocal microscope. For detection of ERK1/2, cells were plated and Western blot analysis was performed. RESULTS: PDL cells on synthetic oligopeptide coated dishes showed enhanced cell adhesion and proliferation. Western blot analysis revealed increased level of ERK1/2 phosphorylation in cells plated on FN fragment containing fibrin-binding domain(FF1 and FF5) coated dishes. CONCLUSION: These results reveals that FN fragment containing fibrin-binding domain possess an enhanced biologic effect of PDL ligament cells.
Binding Sites ; Blotting, Western ; Cell Adhesion ; Fibrin ; Fibronectins ; Ligaments ; Oligopeptides ; Peptides ; Periodontal Ligament ; Phosphorylation

No abstract available.
Fibroblasts* ; Glycyrrhetinic Acid* ; Humans*

BACKGROUND: The aim of this study was to investigate the neuroprotective effects of sevoflurane after severe forebrain ischemic injury. We also examined the relationship between the duration of ischemia and neuronal cell death. METHODS: Male Sprague-Dawley rats (300-380 g) were subjected to 6 (each n = 6) or 10 min (each n = 10) of near-complete forebrain ischemia while anesthetized with either 50 mg/kg of zoletil given intraperitoneally or inhaled sevoflurane (2.3%). Ischemia was induced by bilateral common carotid artery occlusion plus hemorrhagic hypotension (26-30 mmHg). Histologic outcomes were measured 7 days after ischemia in CA1 pyramidal cells of the rat hippocampus. RESULTS: The mean percentage of necrotic cells in the hippocampal CA1 area decreased in the sevoflurane group compared to the zoletil group (25% vs. 40% after 6 min ischemia, respectively: P = 0.004 and 44% vs. 54% after 10 min of ischemia, respectively P = 0.03). The percentage of apoptotic cells was similar in all groups. The percentage of necrotic cells in each anesthetic groups was significantly higher in the 10 min ischemia group compared to the 6 min ischemia group (P = 0.004 in the sevoflurane group, P = 0.03 in the zoletil group). CONCLUSIONS: The present data show that sevoflurane has neuroprotective effects in rats subjected to near-complete cerebral ischemia. Longer duration of ischemia is associated with more neuronal injury when compared to ischemia of shorter duration.
Anesthetics, Inhalation ; Animals ; Brain Ischemia ; Carotid Artery, Common ; Drug Combinations ; Hippocampus ; Humans ; Hypotension ; Ischemia ; Male ; Methyl Ethers ; Neurons ; Neuroprotective Agents ; Prosencephalon ; Pyramidal Cells ; Rats ; Rats, Sprague-Dawley ; Tiletamine ; Zolazepam

PURPOSE: Immune pathophysiology of aplastic anemia (AA) has been indirectly inferred from responses to immunosuppressive agents. An association between AA and HLA-A2, or HLA-DR2 (its serologic split, HLA-DR15; or its molecular correspondents, DRB1*1501) has been implicated. The presence of HLA-DR15 (including DR2 or DRB1*15) has been closely associated with a favorable response to immunosuppression in AA. This study was aimed to characterize Korean patients with AA by determining the association with certain HLA alleles, such as HLA-DR2 or HLA-A2, and their implications in terms of the response to immunosuppression. METHODS: One-hundred eighteen children with AA from 10 university hospitals between 1990 and 2001 were enrolled in this multicenter, retrospective study. Among them, HLA data were available from 80 patients. Tests of proportions were used to compare allelic frequencies. RESULTS: The frequency of HLA-A2 (58.8%) or HLA-DR2 (24.7%) in AA was not significantly different from those of the controls. Analysis of the patients treated with immunosuppression (N=86) showed that, 50.0% of patients showed a response, including 16.0% of complete response at 6 months. The presence of DR2 allele did not portend a favorable response to immunosuppressive therapy. CONCLUSION: Unlike Western countries, the association of AA with certain HLA alleles was not documented in the Korean population. Moreover, the presence of HLA-DR2 did not predict a favorable response to immunosuppression. This peculiar characteristics of Korean AA needs to be investigated whether these findings reflect ethnic differences, different contribution of immune-mediated AA, different immune mechanisms, or mere limitation by number of study patients.
Alleles* ; Anemia, Aplastic* ; Child* ; HLA-A2 Antigen ; HLA-DR2 Antigen ; Hospitals, University ; Humans ; Immunosuppression ; Immunosuppressive Agents ; Retrospective Studies