OBJECTIVES: In this study, we investigated the biodegradation features of 4 perfluorooctanesulfonate (PFOS) alternatives developed at Changwon National University compared to those of PFOS. METHODS: Biodegradation testing was performed with microorganisms cultured in the good laboratory practice laboratory of the Korea Environment Corporation for 28 days following the Organization for Economic Cooperation and Development guidelines for the testing of chemicals (Test No. 301 C). RESULTS: While C₈F₁₇SO₃Na, PFOS sodium salt was not degraded after 28 days, the 4 alternatives were biodegraded at the rates of 20.9% for C₁₅F₉H₂₁S₂O₈Na₂, 8.4% for C₁₇F₉H ₂₅S₂O₈Na₂, 22.6% for C₂₃F₁₈H₂₈S₂O₈Na₂, and 23.6% for C₂₅F₁₇H₃₂O₁₃S₃Na₃. CONCLUSIONS: C₂₅F₁₇H₃₂S₃O₁₃Na₃, C₂₃F₁₈H₂₈S₂O₈Na₂, and C₁₅F₉H₂₁S₂O₈Na₂ were superior to PFOS in terms of biodegradation rates and surface tension, and thus they were considered highly applicable as PFOS alternatives. Environmental toxicity, human toxicity, and economic feasibility of these compounds should be investigated prior to their commercialization.
Gyeongsangnam-do ; Humans ; Korea ; Organisation for Economic Co-Operation and Development ; Sodium ; Surface Tension

BACKGROUND/AIMS: Endoscopic mucosal resection with circumferential mucosal incision (CMI-EMR) may offer benefits comparable to those of endoscopic submucosal dissection (ESD), while requiring less technical proficiency than ESD. METHODS: We retrospectively compared the outcomes of CMI-EMR (n=34) and size-matched ESD (n=102), which were performed by a Korean endoscopist for colorectal epithelial lesions of 20–35 mm. Procedural parameters of CMI-EMRs performed by an American ESD novice (n=30) were compared with those performed by the Korean endoscopist. RESULTS: The lesion size was 22.3±3.9 mm and 22.9±2.4 mm in the CMI-EMR and size-matched ESD groups, respectively (p=0.730). The resection time was 12.7±7.0 minutes in the CMI-EMR group and 45.6±30.1 minutes in the ESD group (p<0.001). The en bloc resection rate was 94.1% in the CMI-EMR group and 100% in the ESD group (p=0.061). There were no differences in the en bloc resection and complication rates of CMI-EMRs between a Korean and an American endoscopist. CONCLUSIONS: For the treatment of moderate-size colorectal lesions, CMI-EMR showed a trend toward lower en bloc resection rate, but required shorter procedure time than ESD. CMI-EMR outcomes were similar when performed by a Korean ESD expert and an American ESD novice.
Colon ; Colorectal Neoplasms* ; Rectum ; Retrospective Studies

BACKGROUND/AIMS: There are a limited number of studies concerning the outcomes of diverticulitis in the Oriental population. We sought to evaluate the clinical features and the long-term outcomes of diverticulitis in Korean patients. METHODS: We retrospectively reviewed the clinical courses of 104 patients (59 men, 45 women; median age 48.5 years [range: 24-83 years]) hospitalized for their first episode of diverticulitis between 1989 and 2005. RESULTS: Right-sided diverticulitis was more common (71/104, 68%). However, the proportion of left-sided diverticulitis increased as age increased. Thirty-two patients underwent operations: 30 because of complications and 2 because of presumed appendicitis. Left-sided diverticulitis was an independent risk factor for complications (OR=7.6, p<0.001), and it required surgical treatment more often than right-sided diverticulitis did (61% vs. 17%, p<0.001). Eighty-five patients were followed for a median of 36 months. Four of the 62 medically treated patients developed recurrence of diverticulitis, with a 3-year cumulative recurrence rate of 4.8%. None of the 4 recurrences showed complications, and all were successfully managed using conservative treatment. No predictive factors for the recurrence of diverticulitis could be determined. CONCLUSIONS: The recurrence rate and risk of complications associated with recurrence are low in patients treated conservatively for the first episode of diverticulitis. Therefore, elective surgery to prevent recurrence and complications should be utilized sparingly in patients with diverticulitis.
Appendicitis ; Diverticulitis ; Diverticulitis, Colonic ; Diverticulosis, Colonic ; Humans ; Male ; Recurrence ; Retrospective Studies ; Risk Factors

BACKGROUND/AIMS: The clinical course after endoscopic management of delayed postpolypectomy bleeding (DPPB) has not been clearly determined. This study aimed to assess clinical outcomes after endoscopic hemostasis of DPPB and evaluate risk factors for rebleeding after initial hemostasis. METHODS: We reviewed medical records of 198 patients who developed DPPB and underwent endoscopic hemostasis between January 2010 and February 2015. The performance of endoscopic hemostasis was assessed. Rebleeding negative and positive patients were compared. RESULTS: DPPB developed 1.4±1.6 days after colonoscopic polypectomy. All patients achieved initial hemostasis. Clipping was the most commonly used technique. Of 198 DPPB patients, 15 (7.6%) had rebleeding 3.3±2.5 days after initial hemostasis. The number of clips required for hemostasis was higher in the rebleeding positive group (3.2±1.6 vs. 4.2±1.9, P=0.047). Combinations of clipping with other modalities such as injection methods were more common in the rebleeding positive group (67/291, 23.0% vs. 12/17, 70.6%; P<0.001). Multivariate analysis showed a large number of clips and combination therapy were independent risk factors for rebleeding. All the rebleeding cases were successfully managed by repeat endoscopic hemostasis. CONCLUSIONS: Endoscopic hemostasis is effective for the management of DPPB because of its high initial hemostasis rate and low rebleeding rate. Endoscopists should carefully observe patients in whom a large number of clips and/or combination therapy have been used to manage DPPB because these may be related to the severity of DPPB and a higher risk of rebleeding.
Colonoscopy ; Hemorrhage* ; Hemostasis ; Hemostasis, Endoscopic ; Humans ; Medical Records ; Multivariate Analysis ; Risk Factors

BACKGROUND/AIMS: Although postpolypectomy fever (PPF) without colon perforation or hemorrhage is rare, its incidence and risk factors have not been investigated. The objective of this study was to analyze the incidence and risk factors for PPF among inpatients. METHODS: Seven patients with PPF were matched with 70 patients without PPF from a total of 3,444 patients who underwent colonoscopic polypectomy. The PPF incidence during index hospitalization after colonoscopy was calculated, and univariate and multivariate analyses were performed to calculate the adjusted odds ratios (ORs) for risk factors. RESULTS: PPF without bleeding or perforation in the colon occurred in seven patients (0.2%). The median age was 58 years for cases and 61 years for controls. The median interval from polypectomy to occurrence of fever was 7 hours, and the median duration of fever was 9 hours. Polyp size >2 cm (adjusted OR, 1.08; 95% confidence interval [CI], 1.01 to 1.15; p=0.02) and hypertension (adjusted OR, 14.40; 95% CI, 1.23 to 180.87; p=0.03) were associated with a significantly increased risk of PPF. PPF increased the length of hospitalization. CONCLUSIONS: Although the crude incidence of PPF is low, PPF may prolong hospitalization. Risk factors for PPF include hypertension and large polyps.
Case-Control Studies* ; Colon ; Colonoscopy ; Fever* ; Hemorrhage ; Hospitalization ; Humans ; Hypertension ; Incidence ; Inpatients ; Multivariate Analysis ; Odds Ratio ; Polyps ; Risk Factors

A 34-year-old man was referred to our department for evaluation of his elevated liver function test. He was diagnosed with Langerhans cell histiocytosis 7 years ago because of recurrent pneumothorax. A CT scan showed multifocal intrahepatic duct dilatation with soft tissue infiltration in the right lobe of the liver. An ERCP showed diffuse multifocal strictures of the intrahepatic duct intervening among the normal segments of the duct. A percutaneous needle biopsy of the liver disclosed ductular proliferation, inflammatory cell infiltration and focal cholestasis. Therefore, he was diagnosed with sclerosing cholangitis. He underwent colonoscopy to evaluate for the possibility of ulcerative colitis. The colonoscopy showed erosions and erythema on the mucosa of the appendiceal orifice, another site of erosion at 35 cm from the anal verge and multiple 3~8 mm sized sessile polyps. Biopsies of the colon mucosa disclosed an infiltration of Langerhans cell histiocytosis. We report here on a very rare case of colon involvement of Langerhans cell histiocytosis.
Adult ; Biopsy ; Biopsy, Needle ; Cholangiopancreatography, Endoscopic Retrograde ; Cholangitis, Sclerosing ; Cholestasis ; Colitis, Ulcerative ; Colon ; Colonoscopy ; Constriction, Pathologic ; Dilatation ; Erythema ; Histiocytosis, Langerhans-Cell ; Humans ; Liver ; Liver Function Tests ; Mucous Membrane ; Pneumothorax ; Polyps

BACKGROUND/AIMS: Cyclooxygenase-2 (COX-2), 15-hydroxyprostaglandin dehydrogenase (15-PGDH), and microsomal prostaglandin E synthase-1 (mPGEs-1) regulate prostaglandin E₂ (PGE₂) expression and are involved in colon carcinogenesis. We investigated the expression of PGE₂ and its regulating genes in sporadic human colon tumors and matched normal tissues. METHODS: Twenty colonic adenomas and 27 colonic adenocarcinomas were evaluated. COX-2 and 15-PGDH expression was quantified by real-time polymerase chain reaction. The expression of PGE₂ and mPGEs-1 was measured using enzyme-linked immunosorbent assay and Western blotting, respectively. RESULTS: The expression of COX-2, mPGEs-1, and PGE₂ did not differ between the adenomas and matched distant normal tissues. 15-PGDH expression was lower in adenomas than in the matched normal colonic tissues (P<0.001). In adenocarcinomas, mPGEs-1 and PGE₂ expression was significantly higher (P<0.001 and P=0.020, respectively), and COX-2 expression did not differ from that in normal tissues (P=0.207). 15-PGDH expression was significantly lower in the normal colonic mucosa from adenocarcinoma patients than in the normal mucosa from adenoma patients (P=0.018). CONCLUSIONS: Early inactivation of 15-PGDH, followed by activation of COX-2 and mPGEs-1, contributes to PGE₂ production, leading to colon carcinogenesis. 15-PGDH might be a novel candidate marker for early detection of field defects in colon carcinogenesis.
Adenocarcinoma ; Adenoma ; Blotting, Western ; Carcinogenesis* ; Colon* ; Cyclooxygenase 2 ; Enzyme-Linked Immunosorbent Assay ; Humans* ; Mucous Membrane ; Oxidoreductases* ; Real-Time Polymerase Chain Reaction

Perivascular epithelioid cell tumor (PEComa) is extremely rare, which originated from mesenchymal cells in the intestine, and composed of histologically and immunohistochemically distinctive perivascular epithelioid cells. We report here on a case of PEComa in the sigmoid colon. A 62-year-old woman presented with hematochzia 10 days ago. Her abdominal computed tomography scan showed a 5 cm sized intraluminal fungating heterogeneously enhanced, high density mass, which infiltrated pericolic tissue surrounding the sigmoid colon. Colonoscopy showed a purple colored polypoid mass with lobulating contour in the sigmoid colon. She underwent laparoscopic anterior resection. On the histologic examination, the tumor consisted of polygonal epithelioid cells with sheet-like growth of nests, which looked like alveolar tissues in lung. The tumor cells were strongly positive stained with human melanoma black-45 (HMB-45). Pathologic examination was compatible with PEComa. Sixteen months after surgery, she did well without tumor recurrence after surgery. We review the literatures concerning PEComa of the intestine focusing on endoscopic findings.
Colonic Neoplasms/diagnosis ; Colonoscopy ; Female ; Gastrointestinal Hemorrhage ; Humans ; Melanoma-Specific Antigens/metabolism ; Middle Aged ; Perivascular Epithelioid Cell Neoplasms/*diagnosis/pathology/surgery ; Tomography, X-Ray Computed

BACKGROUND/AIMS: Toll-like receptors (TLRs) serve as pattern recognition receptors that recognize specific molecular patterns of pathogens and can mediate the production of proinflammatory cytokines. Recently, TLRs have been identified as susceptibility genes for Crohn's disease (CD) in several studies from Western populations. We investigated the association of genetic variations in TLR4 and TLR9 with CD in Korean population. METHODS: In 380 CD cases and 380 healthy controls, we performed genotyping for TLR4 Asp299Gly (rs4986790) and Thr399Ile (rs4986791). The genetic variations in the TLR9 -1237T/C (rs5743836) were also examined. RESULTS: Among CD patients genotyped for TLR4 Asp299Gly and TLR9 -1237T/C, none had variant alleles. Similarly, none of the subjects genotyped for TLR4 Thr399Ile showed genetic variations. CONCLUSIONS: Our results indicate that the major genetic variations in TLR4 and TLR9 are rare and may not be associated with susceptibility to CD in Koreans.
Adolescent ; Adult ; Alleles ; Asian Continental Ancestry Group/*genetics ; Crohn Disease/diagnosis/ethnology/*genetics ; Female ; Genetic Predisposition to Disease ; Genotype ; Humans ; Male ; Republic of Korea ; Toll-Like Receptor 4/*genetics ; Toll-Like Receptor 9/*genetics

Hemangiomas of the small intestine are uncommon benign tumors, of which 90% present with symptoms such as acute or chronic recurrent gastrointestinal bleeding, while 10% of the cases are asymptomatic. The preoperative diagnosis is challenging. We report a case of ileal hemangioma detected incidentally on abdominopelvic computed tomography (CT). In this case, we performed double balloon enteroscopy to confirm the diagnosis before surgical resection, which helped with the therapeutic plan.
Caves ; Double-Balloon Enteroscopy ; Endoscopy, Digestive System ; Hemangioma ; Hemangioma, Cavernous ; Hemorrhage ; Ileum ; Intestine, Small