Shin Kwang Kang

Clinical Features of Deep Neck Infections and Predisposing Factors for Mediastinal Extension

Background Deep neck infections (DNI) can originate from infection in the potential spaces and fascial planes of the neck. DNI can be managed without surgery, but there are cases that need surgical treatment, especially in the case of mediastinal involvement. The aim of this study is to identify clinical features of DNI and analyze the predisposing factors for mediastinal extension. Materials and Methods We reviewed medical records of 56 patients suffering from DNI who underwent cervical drainage only (CD group) and those who underwent cervical drainage combined with mediastinal drainage for descending necrotizing mediastinitis (MD group) from August 2003 to May 2009 and compared the clinical features of each group and the predisposing factors for mediastinal extension. Results Forty-four out of the 56 patients underwent cervical drainage only (79%) and 12 patients needed both cervical and mediastinal drainage (21%). There were no differences between the two groups in gender (p=0.28), but the MD group was older than the CD group (CD group, 44.2±23.2 years; MD group, 55.6±12.1 years; p=0.03). The MD group had a higher rate of co-morbidity than the CD group (p=0.04). The CD group involved more than two spaces in 14 cases (32%) and retropharyngeal involvement in 12 cases (27%). The MD group involved more than two spaces in 11 cases (92%) and retropharyngeal involvement in 12 cases (100%). Organism identification took place in 28 cases (64%) of the CD group and 3 cases of (25%) the MD group (p=0.02). The mean hospital stay of the CD group was 21.5±15.9 days and that of the MD group was 41.4±29.4 days (p=0.04). Conclusion The predisposing factors of mediastinal extension in DNI were older age, involvement of two or more spaces, especially including the retropharyngeal space, and more comorbidities. The MD group had a longer hospital stay, higher mortality, and more failure to identify causative organisms of causative organisms than the CD group.

Benign Metastasizing Leiomyoma: Metastasis to Rib and Vertebra

Benign metastasizing leiomyoma is very rare and characterized by the presence of pelvic, peritoneal, nodal, or pulmonary nodules in women with a history of uterine leiomyomas. We report a case of benign metastasizing leiomyoma in a 30-year-old woman who had undergone a prior myomectomy due to uterine cellular leiomyoma 3 years earlier. The patient had a mass on the right sixth rib and 2 masses in the sixth thoracic vertebra. Pathologically, these masses were diagnosed as cellular leiomyomas. Estrogen and progesterone receptors were both positive in the metastatic tumors as well as in the uterine leiomyomas. The diagnosis of benign metastasizing leiomyoma can only be made after careful examination of the primary tumor to exclude small foci of malignant change.

IDH2 deficiency impairs mitochondrial function in endothelial cells and endothelium-dependent vasomotor function.

Mitochondrial NADP(+)-dependent isocitrate dehydrogenase (IDH2) plays an essential role protecting cells against oxidative stress-induced damage. A deficiency in IDH2 leads to mitochondrial dysfunction and the production of reactive oxygen species (ROS) in cardiomyocytes and cancer cells. However, the function of IDH2 in vascular endothelial cells is mostly unknown. In this study the effects of IDH2 deficiency on mitochondrial and vascular function were investigated in endothelial cells. IDH2 knockdown decreased the expression of mitochondrial oxidative phosphorylation (OXPHOS) complexes I, II and III, which lead to increased mitochondrial superoxide. In addition, the levels of fission and fusion proteins (Mfn-1, OPA-1, and Drp-1) were significantly altered and MnSOD expression also was decreased by IDH2 knockdown. Furthermore, knockdown of IDH2 decreased eNOS phosphorylation and nitric oxide (NO) concentration in endothelial cells. Interestingly, treatment with Mito-TEMPO, a mitochondrial-specific superoxide scavenger, recovered mitochondrial fission-fusion imbalance and blunted mitochondrial superoxide production, and reduced the IDH2 knockdown-induced decrease in MnSOD expression, eNOS phosphorylation and NO production in endothelial cells. Endothelium-dependent vasorelaxation was impaired, and the concentration of bioavailable NO decreased in the aortic ring in IDH2 knockout mice. These findings suggest that IDH2 deficiency induces endothelial dysfunction through the induction of dynamic mitochondrial changes and impairment in vascular function.

Nafamostat Mesilate Inhibits TNF-α-Induced Vascular Endothelial Cell Dysfunction by Inhibiting Reactive Oxygen Species Production.

Nafamostat mesilate (NM) is a serine protease inhibitor with anticoagulant and anti-inflammatory effects. NM has been used in Asia for anticoagulation during extracorporeal circulation in patients undergoing continuous renal replacement therapy and extra corporeal membrane oxygenation. Oxidative stress is an independent risk factor for atherosclerotic vascular disease and is associated with vascular endothelial function. We investigated whether NM could inhibit endothelial dysfunction induced by tumor necrosis factor-α (TNF-α). Human umbilical vein endothelial cells (HUVECs) were treated with TNF-α for 24 h. The effects of NM on monocyte adhesion, vascular cell adhesion molecule-1 (VCAM-1) and intracellular adhesion molecule-1 (ICAM-1) protein expression, p38 mitogen-activated protein kinase (MAPK) activation, and intracellular superoxide production were then examined. NM (0.01~100 µg/mL) did not affect HUVEC viability; however, it inhibited the increases in reactive oxygen species (ROS) production and p66shc expression elicited by TNF-α (3 ng/mL), and it dose dependently prevented the TNF-α-induced upregulation of endothelial VCAM-1 and ICAM-1. In addition, it mitigated TNF-α-induced p38 MAPK phosphorylation and the adhesion of U937 monocytes. These data suggest that NM mitigates TNF-α-induced monocyte adhesion and the expression of endothelial cell adhesion molecules, and that the anti-adhesive effect of NM is mediated through the inhibition of p66shc, ROS production, and p38 MAPK activation.

An Isolated True Aneurysm of the Superficial Femoral Artery in a Young Woman - A case report -

A 39-year-old woman was admitted to the hospital due to a pulsatile mass on her right inner thigh that was evident for two months. She did not exhibit any risk factors of atherosclerosis, no evidence of vasculitis, or any signs of previous trauma history. Ultrasound and computed tomography revealed an adult fist-sized aneurysm on the distal superficial femoral artery. The aneurysm was resected and peripheral circulation was restored with the interposition of a saphenous vein graft. The resected aneurysm had three layers that showed atherosclerosis on histological examination.

Nafamostat mesilate attenuates transient focal ischemia/reperfusion-induced brain injury via the inhibition of endoplasmic reticulum stress

Nafamostat mesilate (NM), a serine protease inhibitor, has a broad range of clinical applications that include use as an anticoagulant during hemodialysis in cerebral hemorrhage patients, as a hemoperfusion anticoagulant for patients with intravascular coagulation, hemorrhagic lesions, and hemorrhagic tendencies, and for the improvement of acute pancreatitis. However, the effects of NM on acute cerebral ischemia have yet to be investigated. Thus, the present study utilized a rat model in which transient middle cerebral artery occlusion (MCAO) was used to induce ischemic injury to investigate the effects of NM on infarct volume and histological and biological changes. NM (1mg/kg) was intravenously administered prior to and after the MCAO procedure. Compared to control rats, the administration of NM significantly decreased infarct size and the extent of brain edema after the induction of focal ischemia via MCAO. Additionally, NM treatment attenuated MCAO-induced neuronal degeneration and activation of microglia and astrocytes. NM treatment also inhibited the MCAO-induced expression levels of glucose-regulated protein 78 (GRP78), CATT/EBP homologous protein (CHOP), and p-eukaryotic initiation factor 2α (eIF2α), which are endoplasmic reticulum (ER) stress markers, in the cerebral cortex. The present findings demonstrate that NM exerts neuroprotective effects in the brain following focal ischemia via, at least in part, the inhibition of ER stress.

Upregulation of APE/ref-1 in recurrence stage I, non small cell lung cancer

Lung cancer, the leading cause of cancer-related death, still lacks reliable biomarkers. Apurinic/apyrimidinic endonuclease 1/Ref-1 is a multifunctional protein involved in the base excision repair of DNA damaged by oxidative stress or alkylating compounds, as well as in the regulation of multiple transcription factors. To validate apurinic/apyrimidinic endonuclease 1/Ref-1 as a biomarker for prediction of lung cancer recurrence, we studied 42 patients who received curative resection and mediastinal lymph node dissection for stage I non-small-cell lung cancer. They were divided into 2 groups based on recurrence, and compared by immunohistochemistry staining of paraffin-embedded tissues and Western blot analysis. Immunohistochemical staining showed a significant difference between the cytoplasm and nucleus in patients who had a recurrence compared to those with nonrecurrent adenocarcinoma. In Western blot analysis, the recurrent adenocarcinoma group showed increased expression of apurinic/apyrimidinic endonuclease 1/Ref-1 in cytoplasm, nucleus, and in total. This indicates that apurinic/apyrimidinic endonuclease 1/Ref-1 is unregulated in recurrent stage I adenocarcinoma. For clinical application as a prognostic marker for non-small-cell lung cancer, further investigation into the role of apurinic/apyrimidinic endonuclease 1/Ref-1 in carcinogenesis is needed in an expanded prospective study.

Acute ST-Segment Elevation Myocardial Infarction Due to a Huge Floating Thrombus Mimicking a Myxoma in the Left Atrium

Acute ST-segment elevation myocardial infarction occurs when the blood supply to a coronary artery is completely interrupted. The most common cause of the abrupt occlusion of a coronary artery is the rupture of a vulnerable atherosclerotic plaque. However, embolisms from any sources can be another cause of abrupt coronary obstruction. The authors report a case of acute ST-segment elevation myocardial infarction caused by a huge left atrial thrombus mimicking a myxoma.

Classic Peripheral Signs of Subacute Bacterial Endocarditis

A 50-year-old female patient with visual disturbances was referred for further evaluation of a heart murmur. Fundoscopy revealed a Roth spot in both eyes. A physical examination showed peripheral signs of infective endocarditis, including Osler nodes, Janeway lesions, and splinter hemorrhages. Our preoperative diagnosis was subacute bacterial endocarditis with severe aortic regurgitation. The patient underwent aortic valve replacement and was treated with intravenous antibiotics for 6 weeks postoperatively. The patient made a remarkable recovery and was discharged without complications. We report this case of subacute endocarditis with all 4 classic peripheral signs in a patient who presented with visual disturbance.

Outcomes of the Tower Crane Technique with a 15-mm Trocar in Primary Spontaneous Pneumothorax

Background Video-assisted thoracoscopic surgery (VATS) pulmonary wedge resection has emerged as the standard treatment for primary spontaneous pneumothorax. Recently, single-port VATS has been introduced and is now widely performed. This study aimed to evaluate the outcomes of the Tower crane technique as novel technique using a 15-mm trocar and anchoring suture in primary spontaneous pneumothorax. Methods Patients who underwent single-port VATS wedge resection in Chungnam National University Hospital from April 2012 to March 2014 were enrolled. The medical records of the enrolled patients were reviewed retrospectively. Results A total of 1,251 patients were diagnosed with pneumothorax during this period, 270 of whom underwent VATS wedge resection. Fifty-two of those operations were single-port VATS wedge resections for primary spontaneous pneumothorax performed by a single surgeon. The median age of the patients was 19.3±11.5 years old, and 43 of the patients were male. The median duration of chest tube drainage following the operation was 2.3±1.3 days, and mean postoperative hospital stay was 3.2±1.3 days. Prolonged air leakage for more than three days following the operation was observed in one patient. The mean duration of follow-up was 18.7±6.1 months, with a recurrence rate of 3.8%. Conclusion The tower crane technique with a 15-mm trocar may be a promising treatment modality for patients presenting with primary spontaneous pneumothorax.