Liver transplantation is the only known treatment for patients with end-stage liver failure, but this therapy is limited by the shortage of donor organs. Hepatic tissue engineering combining biomaterial scaffolds and cells have been used as a promising strategy to create engineered liver graft for liver regeneration. Despite significant progress in this field, attempts to create clinically transplantable whole organs have not been as nearly successful. Recently, whole organ decellularization techniques have emerged as a new therapeutic strategy for organ replacement and provided feasibility for clinical translation. The perfusion decellularization method was applied to the whole organ for efficient removal of cellular components and generated organ scaffolds that can maintain the extracellular matrix (ECM) and vascular structure of the native organ. This review paper describes current progress in organ bioengineering for the development of transplantable liver grafts.
Bioengineering ; Extracellular Matrix ; Humans ; Liver ; Liver Failure ; Liver Regeneration ; Liver Transplantation ; Organ Transplantation* ; Perfusion ; Tissue Donors ; Tissue Engineering ; Transplants*

No abstract available.
Eating* ; Gastric Mucosa* ; Hydrochloric Acid* ; Mucous Membrane*

Recently, increasingly invasive therapeutic endoscopic procedures and more complex gastrointestinal surgeries such as endoscopic mucosal resection, endoscopic submucosal dissection, and novel laparoscopic approaches have resulted in endoscopists being confronted more frequently with perforations, fistulas, and anastomotic leakages, for which nonsurgical closure is desired. In this article, we present our experiences with the use of over-the-scope clip (OTSC) for natural orifice transluminal endoscopic surgery (NOTES) closure, prevention of perforation, anastomotic leakages, and fistula closures. The OTSC is a valuable device for closing intestinal perforations and fistulas, for NOTES closure, and for the prevention of perforation after the excision of a tumor from the proper muscle layer. Furthermore, it seems to be quite safe to perform, even by endoscopists with little experience of the technique.
Anastomotic Leak ; Fistula ; Gastrointestinal Tract* ; Intestinal Perforation ; Natural Orifice Endoscopic Surgery ; Tertiary Care Centers*

OBJECTIVES: For Parkinsonian patients who had not reacted favorably on drug therapy are good candidate for ventroposterolateral pallidotomy, although not curative. We studied these patients after unilateral pallidotomy, to confirm the effectiveness and safety of this procedure. METHODS: We evaluated the 17 patients with idiopathic Parkinson's diesease who had undergone unilateral posteroventral pallidotomy. All patients responded to levodopa initially. Mean age was 55 years(38-75years), and mean duration of disease was 9.8 years(3-20years). Pre-and postoperative evaluation at 3 month intervals included Unified Parkinson's Disease Rating scale(UPDRS) scoring, Hoehn and Yahr(H and Y) staging, and neuropsychological examinations. RESULTS: Pallidotomy significantly improved parkinsonian symptom(tremor, rigidity, bradykinesia, dyskinesia, sensory symptom). Nine of 10 patients who showed dyskinesia preoperatively significant improvement. The mean dose of levodopa in 9 patients was lowered. The mean H and Y score and UPDRS score were improved in on and/or off time in 15 patients. Among patients who were not improved, one patient worsened, and the others showed no change. The mean overall UPDRS off score changed from 76 preoperatively to 44(33%) at 6 months and from 70 to 52(25%) at 1 year. Transient surgical morbidity was showen in four patients and included dysarthria, hypotonia and confusion. CONCLUSION: We conclude that pallidotomy is safe and effective in patients who have levodopa-reponsive parkinsonism with severe symptom fluctuation. Unilateral pallidotomy also considered helpful to ipsilateral symptom. Unilateral pallidotomy can improve all of parkinsonian's symptom and allow to reduce the levodopa medication. Most of patients show satisfactory results.
Drug Therapy ; Dysarthria ; Dyskinesias ; Humans ; Hypokinesia ; Levodopa ; Muscle Hypotonia ; Pallidotomy* ; Parkinson Disease ; Parkinsonian Disorders

Single unit responses of the ventral posterior medial (VPM) thalamic neurons to stimulation were monitored in anesthetized rats during activation of contralateral primary somatosensory (SI) cortex by GABA antagonist. The temporal changes of afferent sensory transmission were quantitatively analyzed by poststimulus time histogram (PSTH). Mainly, afferent sensory transmission to VPM thalamus was facilitated (15 neurons of total 23) by GABA antagonist (bicuculline) applied to contralateral cortex, while 7 neurons were suppressed. However, when ipsilateral cortex was inactivated by GABA agonist, musimol, there was significant suppression of afferent sensory transmission of VPM thalamus. This suppressed responsiveness by ipsilateral musimol was not affected by bicuculline applied to contralateral cortex. These results suggest that afferent transmission to VPM thalamus may be subjected to the interhemispheric modulation via ipsilateral cortex during inactivation of GABAergic neurons in contralateral SI cortex.
Animals ; Bicuculline ; GABA Agonists ; GABA Antagonists ; GABAergic Neurons ; gamma-Aminobutyric Acid ; Neurons ; Rats ; Somatosensory Cortex* ; Thalamus*

We descrive a 23-year-old female of 46, XXqi Turner's syndrome associated with large atrial sepatal defect(secundum type) and mitral valve prolapse who was admitted due to amenorrhea, sexual infantilism and exertional dyspnea. This patient had only one spontaneous menstrual period at the age of 15 and had a short stature without webbed neck. Chromosomal aberrations cause primarily structural defects of cardiovasculaqr system, and a variety of structural aberrations involving the X chromosome and cause partial or complete Turner's syndrome. In Turner's syndrome, bicuspid aortic valve or coarctaton of aorta is frequently combined, also aortic root dilatation, partial anomalous venous drainage, hypoplastic left heart and ventricular septal defect, atrial septal defect has been reported. However, this patient had not abnormalities in aortic valve and whole aorta. Atrial septal defect simultaneously with mitral valve prolapse in 46 XXqi Turner's syndrome have not been reported in Korea. We report this case with a brief review of the literature.
Amenorrhea ; Aorta ; Aortic Valve ; Bicuspid ; Chromosome Aberrations ; Dilatation ; Drainage ; Dyspnea ; Female ; Heart ; Heart Septal Defects, Atrial ; Heart Septal Defects, Ventricular ; Humans ; Korea ; Mitral Valve Prolapse ; Mitral Valve ; Neck ; Sexual Infantilism ; Turner Syndrome ; X Chromosome ; Young Adult

BACKGROUND/AIMS: Providers may be hesitant to perform double-balloon enteroscopy (DBE) in the elderly because the increased number of co-morbidities in this population poses a greater risk of complications resulting from sedation. There are limited data on the use of DBE in the elderly. Here, we assessed the safety and efficacy of DBE in the elderly compared to those in younger patients. METHODS: We retrospectively analyzed the medical records of 158 patients who underwent 218 DBEs. Patients were divided into an elderly group (age > or =65 years; mean 71.4+/-5.4; n=34; 41 DBEs) and a younger group (age <65 years; mean 39.5+/-13.5; n=124; 177 DBEs). RESULTS: In both groups, the most common indication for DBE was obscure gastrointestinal bleeding. Mucosal lesions (33.3% vs. 60.9%; P=0.002) were the most common finding in both groups, followed by tumors (30.8% vs. 14.1%; P=0.036). The elderly were more likely to receive interventional therapy (51.3% vs. 23.5%; P=0.001). The diagnostic yield of DBE was slightly higher in the elderly group (92.3% vs. 86.5%; P=0.422), but was not statistically significant. The therapeutic success rate of DBE was 100% in the elderly group compared to 87.5% in the younger group (P=0.536). The overall DBE complication rate was 1.8% overall, and this rate did not differ significantly between the groups (2.6% vs. 1.7%; P=0.548). CONCLUSIONS: DBE is safe and effective in the elderly, and has a high diagnostic yield and high therapeutic success rate.
Aged* ; Double-Balloon Enteroscopy* ; Hemorrhage ; Humans ; Medical Records ; Retrospective Studies

PURPOSE: To assess the feasibility of transluminal radiofrequency thermal ablation using a stent-type electrode and to determine, by means of in-vitro and in-vivo animal studies, the appropriate parameters. MATERIALS AND METHODS: In vitro: The radiofrequency electrode used was a self-expandable nitinol stent with 1cm insulated ends. A stent was placed in the portal vein of bovine liver, and ablations at target temperatures of 70, 80, 90, and 100degrees C were performed. Ablated sizes were measured longitudinally. In vivo: Four mongrel dogs were anesthetized, and a stent was inserted in the common bile duct under fluoroscopic guidance through an ultrasound-guided gall bladder puncture site. The ablation temperature was set at 80 degrees C, and each dog underwent proximal and distal esophageal ablations lasting 12 minutes. They were sacrificed immediately. RESULTS: In-vitro: Ablated sizes showed significant correlation with target temperatures (r>0.04; p<0.05). Although most lesions were fusiform, dumbbell-shaped lesions with central thinning were found in two cases in the 70degrees C group. In all cases in the 70 degrees C and 80 degrees C group, the length of the insulated segment was less than 1 cm. In-vivo: At microscopy, tissues at the center of the biliary stent showed more prominent pathological change than those at the periphery while those remote from the stent showed minimal or no change. In esophageal ablations, the mean highest temperature was 48.6 degrees C. Microscopy demonstrated the destruction and shedding of mucosa, edema, and coagulation necrosis of submucosa, but in muscle layers no abnormalities were apparent. CONCLUSION: Transluminal radio-frequency thermal ablation using a stent-type electrode may be useful for elongating patency. The appropriate target temperature for biliary ablation is 80 degrees C.
Animals ; Common Bile Duct ; Dogs ; Edema ; Electrodes* ; Liver ; Microscopy ; Mucous Membrane ; Necrosis ; Portal Vein ; Punctures ; Stents ; Urinary Bladder

BACKGROUND: The structure and function of bone tissue is maintained through a constant remodeling process, which is maintained by the balance between osteoblasts and osteoclasts. The failure of bone remodeling can lead to pathological conditions of bone structure and function. Remifentanil is currently used as a narcotic analgesic agent in general anesthesia and sedation. However, the effect of remifentanil on osteoclasts has not been studied. Therefore, we investigated the effect of remifentanil on pre-osteoclast (pre-OCs) differentiation and the mechanism of osteoclast differentiation in the absence of specific stimulus. METHODS: Pre-OCs were obtained by culturing bone marrow-derived macrophages (BMMs) in osteoclastogenic medium for 2 days and then treated with various concentration of remifentanil. The mRNA expression of NFATc1 and c-fos was examined by using real-time PCR. We also examined the effect of remifentanil on the osteoclast-specific genes TRAP, cathepsin K, calcitonin receptor, and DC-STAMP. Finally, we examined the influence of remifentanil on the migration of pre-OCs by using the Boyden chamber assay. RESULTS: Remifentanil increased pre-OC differentiation and osteoclast size, but did not affect the mRNA expression of NFATc1 and c-fos or significantly affect the expression of TRAP, cathepsin K, calcitonin receptor, and DC-STAMP. However, remifentanil increased the migration of pre-OCs. CONCLUSIONS: This study suggested that remifentanil promotes the differentiation of pre-OCs and induces maturation, such as increasing osteoclast size. In addition, the increase in osteoclast size was mediated by the enhancement of pre-OC migration and cell fusion.
Anesthesia, General ; Bone and Bones ; Bone Remodeling ; Cathepsin K ; Cell Differentiation ; Cell Fusion ; Cell Movement ; In Vitro Techniques ; Macrophages ; Osteoblasts ; Osteoclasts ; Real-Time Polymerase Chain Reaction ; Receptors, Calcitonin ; RNA, Messenger

BACKGROUND/AIMS: Colorectal cancer is associated with different anatomical, biological, and clinical characteristics. We determined the impact of the primary tumor location in patients with metastatic colorectal cancer (mCRC). METHODS: Demographic data and clinical information were collected from 1,115 patients from the Republic of Korea, who presented with mCRC between January 2009 and December 2011, using web-based electronic case report forms. Associations between the primary tumor location and the patient's clinical characteristics were assessed, and factors inf luencing overall survival were analyzed using Cox proportional hazards regression models. RESULTS: Of the 1,115 patients recruited to the study, 244 (21.9%) had right colon cancer, 483 (43.3%) had left colon cancer, and 388 (34.8%) had rectal cancer. Liver and lung metastases occurred more frequently in patients with left colon and rectal cancer (p = 0.005 and p = 0.006, respectively), while peritoneal and ovarian metastases occurred more frequently in patients with right and left colon cancer (p < 0.001 and p = 0.031, respectively). The median overall survival of patients with tumors originating in the right colon was significantly shorter than that of patients whose tumors had originated in the left colon or rectum (13.7 months [95% confidence interval (CI), 12.0 to 15.5] vs. 18.0 months [95% CI, 16.3 to 19.7] or 19.9 months [95% CI, 18.5 to 21.3], respectively; p = 0.003). Tumor resection, the number of metastatic sites, and primary tumor location correlated with overall survival in the univariate and multivariate analyses. CONCLUSIONS: Primary tumor location influences the metastatic sites and prognosis of patients with mCRC.
Colon ; Colonic Neoplasms ; Colorectal Neoplasms* ; Humans ; Liver ; Lung ; Multivariate Analysis ; Neoplasm Metastasis ; Prognosis ; Rectal Neoplasms ; Rectum ; Republic of Korea