Hyojun Park

Treatment of thoracic actinomycosis: A retrospective analysis of 40 patients

BACKGROUND: The aim of this study was to evaluate treatment outcomes in patients with thoracic actinomycosis and identify patient characteristics associated with unfavorable responses to antibiotic therapy. METHODS: A retrospective analysis was performed on 40 patients with pathologically confirmed thoracic actinomycosis. RESULTS: Initial surgical treatment was performed on 17 patients to control severe symptoms such as hemoptysis or rule out lung cancer. Sixteen (94%) patients were successfully treated, including three patients who did not receive postoperative antibiotics, and one patient died of a postoperative complication. The median duration of oral antibiotic therapy after surgery was 3 months. After the diagnosis of actinomycosis, 23 patients began antibiotic therapy. The median duration of oral antibiotic therapy was 5 months. Favorable treatment outcomes were achieved in 18 of these 23 patients (78%), while five (22%) showed unfavorable responses to antibiotic therapy. Surgery was successfully performed in these five patients. The patients with unfavorable responses to antibiotic therapy had a longer duration of symptoms prior to treatment (median, 10 months) as compared to patients with favorable responses (median, 2 months; P = 0.012). CONCLUSIONS: Medical treatment failure is possible in patients with thoracic actinomycosis, and close monitoring is necessary in those who begin antibiotic therapy. In addition, surgical resection may be a valid option for patients who do not respond to antibiotic therapy, with the consideration of the age and comorbid conditions.

Radical resection of intestinal blue rubber bleb nevus syndrome

Blue rubber bleb nevus syndrome (BRBNS) is a rare systemic vascular disorder characterized by multiple venous malformations involving many organs. BRBNS can occur in various organs, but the most frequently involved organs are the skin and gastrointestinal (GI) tract. GI lesions of BRBNS can cause acute or chronic bleeding, and treatment is challenging. Herein, we report a case of GI BRBNS that was successfully treated with a combination of intraoperative endoscopy and radical resection.

Xenotransplantation of layer-by-layer encapsulated non-human primate islets with a specified immunosuppressive drug protocol

ABSTRACT Islet transplantation is as effective as but also less immunogenic than pancreas transplantation for the treatment of type 1 diabetes mellitus. However, as the complete elimination of immunogenicity still remains a major obstacle in islet transplantation, layer‐by‐layer encapsulation (LbL) of pancreatic islets using biocompatible polymers offers a rational approach to reducing host immune response towards transplanted islets. We investigated the effect of LbL of non‐human primate (NHP) islets on reducing immunogenicity as a preclinical model since NHPs have close phylogenetic and immunological relationship with humans. LbL with three‐layers of polyethylene glycol (PEG) molecules (SH‐6‐arm‐PEG‐NHS, 6‐arm‐PEG‐catechol and linear PEG‐SH) showed a uniform nano‐shielding on islets without the loss of viability or function of islets. An immunosuppressive drug protocol was also combined to improve the survival rate of the transplanted islets in vivo. A xenorecipient (C57BL/6 mice) of LbL islet transplanted along with our immunosuppressive drug protocol showed 100% survival rate for 150 days after transplantation. On the other hand, naked islet recipients showed poor survival time of 5.5 ± 1.4 days without drugs and 77.5 ± 42 days with the drug protocol. Immunohistochemistry of the transplanted grafts and serum cytokine concentration demonstrated less immunogenicity in the LbL islet transplanted recipients compared with the naked islet ones.

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.

CDK4 Amplification Predicts Recurrence of Well-Differentiated Liposarcoma of the Abdomen

Background The absence of CDK4 amplification in liposarcomas is associated with favorable prognosis. We aimed to identify the factors associated with tumor recurrence in patients with well-differentiated (WD) and dedifferentiated (DD) liposarcomas. Methods From 2000 to 2010, surgical resections for 101 WD and DD liposarcomas were performed. Cases in which complete surgical resections with curative intent were carried out were selected. MDM2 and CDK4 gene amplification were analyzed by quantitative real-time polymerase chain reaction (Q-PCR). Results There were 31 WD and 17 DD liposarcomas. Locoregional recurrence was observed in 11 WD and 3 DD liposarcomas. WD liposarcomas showed better patient survival compared to DD liposarcomas (P<0.05). Q-PCR analysis of the liposarcomas revealed the presence of CDK4 amplification in 44 cases (91.7%) and MDM2 amplification in 46 cases (95.8%). WD liposarcomas with recurrence after surgical resection had significantly higher levels of CDK4 amplification compared to those without recurrence (P = 0.041). High level of CDK4 amplification (cases with CDK4 amplification higher than the median 7.54) was associated with poor recurrence-free survival compared to low CDK4 amplification in both univariate (P = 0.012) and multivariate analyses (P = 0.020). Conclusions Level of CDK4 amplification determined by Q-PCR was associated with the recurrence of WD liposarcomas after surgical resection.

The use of suction blisters for the recipient area in epidermal grafting for vitiligo

© 2008 The Authors JEADV 2009, 23, 835–862 Journal compilation

Comparative characterization of mesenchymal stromal cells from multiple abdominal adipose tissues and enrichment of angiogenic ability via CD146 molecule

BACKGROUND There are various types of adipose tissue in the human body, and their morphology is known to be closely related to cell function and metabolism. However, the functional differences among the mesenchymal stromal cells (MSCs) of different abdominal adipose tissues have not been clearly elucidated. METHODS MSCs were isolated from different abdominal adipose tissues according to their regional distribution and included superficial subcutaneous, deep subcutaneous, omentum, mesentery and retroperitoneal MSCs. The immunophenotype, proliferative ability and angiogenic function of these MSCs were compared based on flow cytometry analysis, CCK-8 proliferation, in vitro differentiation, tubule formation and in vivo plug assay. RESULTS The plastic adherence, cell morphology and general immunophenotype are similar among the MSCs. However, subcutaneous adipose tissue-derived MSCs have a faster growth rate and a higher level of CD146 expression than the other MSCs. Moreover, according to the fluorescence-activated cell sorting (FACS) enrichment procedure, the expression level of CD146 is positively related to the growth rate and angiogenic capability of MSCs. DISCUSSION MSCs in adipose tissue showed slightly different characteristics depending on their location of origin, and they possessed different angiogenic abilities that were mediated by the expression of CD146. This study provides evidence that subcutaneous adipose tissue is the most appropriate source of MSCs for therapeutic cell transplantation in vascular disease.

Tissue expander placement and adjuvant radiotherapy after surgical resection of retroperitoneal liposarcoma offers improved local control.

AbstractGiven that retroperitoneal liposarcoma (LPS) is extremely difficult to completely resect, and has a relatively high rate of recurrence, radiotherapy (RT) is the treatment of choice after surgical resection. However, it is difficult to obtain a sufficient radiation field because of the close proximity of surrounding organs. We introduce the use of tissue expanders (TEs) after LPS resection in an attempt to secure a sufficient radiation field and to improve recurrence-free survival.This study is a retrospective review of 53 patients who underwent surgical resection of LPS at Samsung Medical Center between January 1, 2005, and December 31, 2012, and had no residual tumor detected 2 months postoperatively. The median follow-up period was 38.9 months.Patients were divided into 3 groups. Those in group 1 (n = 17) had TE inserted and received postoperative RT. The patients in group 2 (n = 9) did not have TE inserted and received postoperative RT. Finally, those in group 3 (n = 27) did not receive postoperative RT. Multivariate analysis was performed to identify the risk factors associated with recurrence-free survival within 3 years. Younger age, history of LPS treatment, and RT after TE insertion (group 1 vs group 2 or 3) were significantly favorable factors influencing 3-year recurrence-free survival.TE insertion after LPS resection is associated with increased 3-year recurrence-free survival, most likely because it allows effective delivery of postoperative RT.

High pretransplant HBV level predicts HBV reactivation after kidney transplantation in HBV infected recipients

Purpose HBsAg-positive kidney recipients are at increased risk for mortality and graft failure. The aims of this study were to identify the outcomes of HBsAg-positive recipients who received preemptive antiviral agents after successful kidney transplantation and to analyze risk factors for HBV reactivation. Methods We retrospectively reviewed the medical records of 944 patients performed kidney transplantation between 1999 and 2010. Results HBsAg-negative recipients were 902 patients and HBsAg-positive recipients, 42. Among HBsAg-positive recipients, HBV reactivation was detected in 7 patients and well controlled by switch or combination therapy. Graft failure developed in only one patient due to chronic rejection regardless of HBV reactivation but no deaths occurred. All patients were alive at the end of follow-up and none developed end-stage liver disease or hepatocellular carcinoma. There was statistically significant difference in graft survival between HBsAg-positive recipients and HBsAg-negative. Multivariate analysis identified increased HBV DNA levels (>5 × 104 IU/mL) in the HBsAg-positive kidney transplant recipients as a risk factor for HBV reactivation (P = 0.007). Conclusion Effective viral suppression with antiviral agents in HBsAg-positive renal transplant recipients improves patient outcome and allograft survival. Antiviral therapy may be especially beneficial in patients with high HBV DNA levels prior to transplantation.

Clinical benefit and residual kidney function of en bloc nephrectomy for perirenal retroperitoneal sarcoma

The purpose of this study was to evaluate the efficacy of en bloc nephrectomy for perirenal retroperitoneal sarcoma (RPS) with respect to postoperative kidney function and oncological benefits.