Min Jung Kim

TBAF-assisted copper-catalyzed N-arylation and benzylation of benzazoles with aryl and benzyl halides under the ligand/base/ solvent-free conditions.

TBAF-assisted N-arylation and benzylation of benzazoles such as 1H-benzimidazole, 1H-indole, and 1H-benzotriazole with aryl and benzyl halides have been demonstrated under the ligand/base/solvent-free conditions. In the presence of CuBr2 and TBAF (n-Bu4NF), the azoles underwent N-arylation and benzylation with aryl and benzyl halides smoothly in moderate to good yields. It is noteworthy that the reaction is conducted under the ligand/base/solvent-free conditions.

Single-incision laparoscopic splenectomy versus conventional multiport laparoscopic splenectomy: a retrospective comparison of outcomes.

Background. The authors report their experience with single-incision laparoscopic splenectomy (SLS) and compare postoperative outcomes of conventional multiport laparoscopic splenectomy (MLS) with SLS in patients with spleen sizes ≤15cm. Methods. Demographic, intraoperative, and postoperative data were analyzed retrospectively and compared between patients who underwent MLS from June 20, 2006, to July 9, 2009 (MLS group, 18 patients) and those who underwent SLS from July 28, 2009, to November 2, 2010 (SLS group, 16 patients). Results. Blood loss was significantly greater in the SLS group than in the MLS group (206.25 ± 142.45 vs 111.11 ± 99.58 mL, respectively; P = .047). The Numeric Pain Rating Scale in the SLS group was significantly lower than in the MLS group (3.81 ± 0.91 vs 4.56 ± 1.29, respectively; P = .041). There were no significant differences between the groups for other variables. Conclusions. SLS is a feasible method with good cosmetic benefit and equivalent clinical outcomes as compared with MLS.

Post-transplant lymphoproliferative disorder localized in the colon after liver transplantation: Report of a case

Post-transplant lymphoproliferative disorder (PTLD) is a life-threatening complication of any organ transplantation. It is more common in children than in adults, and the risk factors include Epstein-Barr virus (EBV) infection and immunosuppression. We report a case of colonic marginal zone B-cell lymphoma occurring 4 years after liver transplantation in a 52-year-old man who had been taking immunosuppressive agents, namely, cyclosporin, mycophenolate mofetil (MMF), and prednisolone. A routine follow-up colonoscopy showed a 2.0-cm diffuse nodular transverse colon polyp covered with erosive mucosa. Snare polypectomy was done without any complications. Immunohistochemical staining was positive for CD3 and CD20 in the interstitially scattered small lymphocytes and negative for Bcl-2, revealing marginal zone B-cell lymphoma. EBV quantitative polymerase chain reaction was less than the detection limit (<10 copies/5 µl whole blood). Extraintestinal whole-body screening was negative. The patient underwent right hemicolectomy after colonoscopic tattooing for positive resection margins on snare polypectomy. Surgical pathology revealed no evidence of residual lymphoma. Treatment consisted of colonic resection and reduction of the doses of immunosuppressants. The patient is currently under close surveillance without any signs of recurrence.

Hand-Assisted Laparoscopic Nephrectomy and Auto-Transplantation for a Hilar Renal Artery Aneurysm: A Case Report

A 52-year-old man was admitted with an incidentally detected right renal artery aneurysm (RAA). Computed tomographic angiography with three-dimensional reconstruction revealed that the aneurysm was 2.2 cm in diameter and located at the renal hilum. We performed hand-assisted laparoscopic nephrectomy with ex vivo repair of the RAA and auto-transplantation with minimal elongation of Gibson incision. The operation and postoperative course were uneventful. At last follow-up, the patient was alive with a well-functioning auto-transplant. Hand-assisted laparoscopic nephrectomy and auto-transplantation is a useful treatment option for hilar RAA.

Finding Frequent Itemsets Over Data Streams in Confined Memory Space

ABSTRACT Due to the characteristics of a data stream, it is very important to confine the memory usage of a data mining process regardless of the amount of information generated in the data stream. For this purpose, this paper proposes the Prime pattern tree(PPT) for finding frequent itemsets over data streams with using the confined memory space. Unlike a prefix tree, a node of a PPT can maintain the information necessary to estimate the current supports of several itemsets together. The length of items in a prime pattern can be reduced the total number of nodes and controlled by split_delta S δ . The size and the accuracy of the PPT is determined by S δ . The accuracy is better as the value of S δ is smaller since the value of S δ is large, many itemsets are estimated their frequencies. So it is important to consider trade-off between the size of a PPT and the accuracy of the mining result. Based on this characteristic, the size and the accuracy of the PPT can be flexibly controlled by merging or splitting nodes in a mining process. For finding all frequent itemsets over the data stream, this paper proposes a PPT to replace the role of a prefix tree in the estDec method which was proposed as a previous work. It is efficient to optimize the memory usage for finding frequent itemsets over a data stream in confined memory space. Finally, the performance of the proposed method is analyzed by a series of experiments to identify its various characteristics.Keywords:Data Mining, Data Stream, Frequent Itemsets