Yoon Hee Lee

Korea National Sport University, Seoul, Seoul, South Korea

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Publications (17)37.27 Total impact

  • Source
    Article: High prevalence of Opisthorchis viverrini infection in a riparian population in Takeo Province, Cambodia.
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    ABSTRACT: Opisthorchis viverrini infection was found to be highly prevalent in 3 riverside villages (Ang Svay Chek A, B, and C) of the Prey Kabas District, Takeo Province. This area is located in the southern part of Cambodia, where the recovery of adult O. viverrini worms was recently reported. From May 2006 until May 2010, fecal examinations were performed on a total of 1,799 villagers using the Kato-Katz thick smear technique. In the 3 villages, the overall positive rate for helminth eggs ranged from 51.7 to 59.0% (av. 57.4%), and the percentage positive for O. viverrini was 46.4-50.6% (47.5%). Other helminths detected included hookworms (13.2%), echinostomes (2.9%), Trichuris trichiura (1.3%), Ascaris lumbricoides (0.6%), and Taenia spp. (0.06%). The prevalence of O. viverrini eggs appeared to reflect a lower infection in younger individuals (<20 years) than in the adult population (>20 years). Men (50.4%) revealed a significantly higher (P=0.02) prevalence than women (44.3%). The Ang Svay Chek villages of the Prey Kabas District, Takeo Province, Cambodia have been confirmed to be a highly endemic area for human O. viverrini infection.
    The Korean Journal of Parasitology 06/2012; 50(2):173-6. · 1.04 Impact Factor
  • Article: Changes in serum cartilage oligomeric matrix protein (COMP), plasma CPK and plasma hs-CRP in relation to running distance in a marathon (42.195 km) and an ultra-marathon (200 km) race
    Hyo Jeong Kim, Yoon Hee Lee, Chang Keun Kim
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    ABSTRACT: Marathon running is frequently associated with numerous cellular changes, but little information is available on the effects of exercise-mediated prolonged impact-stress on cartilage integrity. This study was undertaken to evaluate muscle and cartilage damage with different running distances. Twenty male marathoners and ultra-marathoners participated in the study. Serum COMP and plasma CPK and hs-CRP were measured as markers of cartilage and muscle damage and inflammation. Serum COMP was increased 1.6-fold at 10km during a marathon race and declined to the pre-race level after 2days recovery. In contrast, serum COMP was increased 1.9-fold after a 200-km race and maintained until day 3 of recovery, only returning to the pre-race level on day 6. Plasma CPK was increased at 10km of the marathon race and up to threefold at the end of the race. This was further increased on day 1, only returning to pre-race level on day 6. Plasma CPK was increased 35-fold at the end of the 200-km race and remained increased until day 5. There was no change in plasma hs-CRP during the marathon race, but this was increased 3.4-fold by day 1, returning to the pre-race level on day 4. Plasma hs-CRP increased 40-fold by the end of the 200-km race and was still increased on day 6 of recovery. Therefore, longer distance running may induce more impact-stress both on muscle and cartilage. Further, the required time for recovery may vary with running distance and the tissue type, e.g. cartilage or skeletal muscle as in this case.
    Arbeitsphysiologie 04/2012; 105(5):765-770. · 2.15 Impact Factor
  • Article: Significance of cell cycle regulatory proteins as malignant and prognostic biomarkers in ovarian epithelial tumors.
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    ABSTRACT: The principal objective of this study was to comprehensively assess the clinicopathologic and prognostic impacts of the expression of various cell cycle regulatory proteins in patients with ovarian epithelial tumors. The tissue microarrays were constructed from formalin-fixed, paraffin-embedded tissues of 205 ovarian epithelial tumors. We investigated 55 benign (20 serous cystadenomas, 17 mucinous cystadenomas, and 18 endometriotic cysts), 72 borderline (26 serous borderline tumors and 46 mucinous borderline tumors), and 78 malignant tumors (45 serous carcinomas, 10 mucinous adenocarcinomas, 15 endometrioid adenocarcinomas, and 8 clear cell carcinomas). Immunohistochemical staining was performed using antibodies to p16(Ink4a), p53, p21(Waf1/Cip1), p27(Kip1), Cyclin D1, Cyclin E, Cyclin A, Cyclin B1, and Cyclin-dependent Kinase2. We noted significantly different levels of p53 and Cyclin B1 expressions between malignant and borderline tumors and between borderline and benign tumors excepting the mucinous type. The p21(Waf1/Cip1) and Cyclin A were significantly overexpressed in malignant tumors compared with borderline tumors. Cyclin A, Cyclin E, and p16(Ink4a) were more pronounced proteins, showing differential expression patterns among the histologic types of ovarian carcinomas. We determined that the overexpression of p16(Ink4a) (P=0.031), Cyclin E (P=0.009), and Cyclin-dependent Kinase2 (P=0.004) were significantly associated with higher tumor grades. Overexpression of p16(Ink4a) was correlated with both lymph node metastasis (P=0.030) and distant metastasis (P=0.034). Overexpression of Cyclin E was associated with advanced stage (P=0.004). Higher tumor grade (P=0.008), advanced stage (P=0.001), mucinous histologic type (P=0.012), low expression levels of p16(Ink4a) (P=0.032), and overexpression of p53 (P=0.032) were associated with poor overall survival on multivariate analysis in patients with ovarian cancer. In serous carcinomas, old age (P=0.005), distant metastasis (P=0.020), low expression of p16(Ink4a) (P=0.047), and overexpression of cytoplasmic p27(Kip1) (P=0.007) and Cyclin A (P=0.031) were all independent predictors of worse overall survival. Our data indicate that the overexpression of p16 and Cyclin E are valuable factors predicting disease progression and metastatic potential. Low p16(Ink4a) expression, overexpression of p53, cytoplasmic p27(Kip1), and Cyclin A are predictive markers for shorter overall survival in ovarian carcinomas.
    International journal of gynecological pathology: official journal of the International Society of Gynecological Pathologists 04/2011; 30(3):205-17. · 2.07 Impact Factor
  • Article: A Case of Lichen Planus Pigmentosus-inversus in a Korean Patient.
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    ABSTRACT: Lichen planus pigmentosus-inversus is a rare variant of lichen planus pigmentosus. The eruption of lichen planus pigmentosus-inversus occurs mainly in the flexural regions and presents with brownish macules and patches. Here we describe the case of a 31-year-old Korean woman who presented with hyperpigmented lesions over her antecubital and popliteal area and groin. Physical examination revealed multiple brownish macules and patches on the intertriginous area without pruritis, and histologic findings showed a regressive pattern of lichen planus. These clinical and histological findings were consistent with a diagnosis of lichen planus pigmentosus-inversus.
    Annals of Dermatology 02/2011; 23(1):61-3. · 0.53 Impact Factor
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    Article: Endoplasmic reticulum stress markers and ubiquitin–proteasome pathway activity in response to a 200-km run.
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    ABSTRACT: This study investigated whether a 200-km run modulates signaling pathways implicated in cellular stress in skeletal muscle, with special attention paid to the endoplasmic reticulum (ER) stress and to the activation of the ubiquitin-proteasome pathway. Eight men ran 200 km (28 h 03 min ± 2 h 01 min). Two muscle biopsies were obtained from the vastus lateralis muscle 2 wk before and 3 h after the race. Mitogen-activated protein kinase, ubiquitin-proteasome pathway, ER stress, inflammation, and oxidative stress markers were assayed by Western blot analysis or by quantitative real-time polymerase chain reaction. Chymotrypsin-like activity of the proteasome was measured by a fluorimetric assay. Phosphorylation states of extracellular signal-related kinase 1/2 (+401% ± 173.8%, P = 0.027) and c-Jun N-terminal (+149% ± 61.9%, P = 0.023) increased after the race, whereas p38 phosphorylation remained unchanged. Increases in BiP (+235% ± 94.7%, P = 0.021) and in the messenger RNA level of total (+138% ± 31.2%, P = 0.002) and spliced X-box binding protein 1 (+241% ± 53.3%, P = 0.001) indicated the presence of ER stress. Transcripts of inflammatory markers interleukin-6 (+403% ± 96.1%, P = 0.002) and tumor necrosis factor-α (+233% ± 58.4%, P = 0.003) as well as oxidative stress markers metallothionein 1F (+519% ± 258.3%, P = 0.042), metallothionein 1H (+666% ± 157.5%, P = 0.002), and nicotinamide adenine dinucleotide phosphate-oxidase (NADPH oxidase) (+162% ± 60.5%, P = 0.016) were increased. The messenger RNA level of the ubiquitin ligases muscle-specific RING finger 1 (+583% ± 244.3%, P = 0.024) and muscle atrophy F-box (+249% ± 83.8%, P = 0.011) and the C2 proteasome subunit (+116% ± 40.6%, P = 0.012) also increased. Surprisingly, the amount of ubiquitin-conjugated proteins and the chymotrypsin-like activity of the proteasome were decreased by 20% ± 8.3% (P = 0.025) and 21% ± 4.4% (P = 0.001), respectively. The expression of ubiquitin-specific protease 28 deubiquitinase was increased (+81% ± 37.9%, P = 0.034). In the skeletal muscle, a 200-km run activates the expression of ubiquitin ligases muscle-specific RING finger 1 and muscle atrophy F-box as well as various cellular stresses, among which are ER stress, oxidative stress, and inflammation. Meanwhile, compensatory mechanisms seem also triggered: the unfolded protein response is up-regulated, and the chymotrypsin-like activity of the proteasome is repressed.
    Medicine and science in sports and exercise 01/2011; 43(1):18-25. · 3.71 Impact Factor
  • Article: Chromosomal instability, telomere shortening, and inactivation of p21WAF1/CIP1 in dysplastic nodules of hepatitis B virus-associated multistep hepatocarcinogenesis
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    ABSTRACT: Systemic analysis for chromosomal instability and inactivation of cell cycle checkpoints are scarce during hepatocarcinogenesis. We studied 24 patients with chronic B viral cirrhosis including 30 cirrhotic regenerative nodules, 35 low-grade dysplastic nodules, 15 high-grade dysplastic nodules, 7 dysplastic nodules with hepatocellular carcinoma foci, and 18 hepatocellular carcinomas. Eight normal livers were studied as the control group. Telomere length and micronuclei were detected by Southern blot and Feulgen-fast green dyeing technique, respectively, and p21WAF1/CIP1 expression was studied by immunohistochemistry. Micronuclei >1 per 3000 hepatocytes were found in 17% of low-grade dysplastic nodules, 87% of high-grade dysplastic nodules, and 100% of high-grade dysplastic nodules with hepatocellular carcinoma foci and hepatocellular carcinomas in contrast to those of all normal livers, and 90% of cirrhosis showed no micronuclei. The micronuclei index showed a gradual increase during hepatocarcinogenesis and there was a significant increase between cirrhosis and low-grade dysplastic nodules, low-grade dysplastic nodules and high-grade dysplastic nodules, and high-grade dysplastic nodules and hepatocellular carcinomas. Telomere length showed a gradual shortening during hepatocarcinogenesis and a significant reduction was found in high-grade dysplastic nodules (P=0.024) and hepatocellular carcinomas (P=0.031) compared with normal and cirrhotic livers. The micronuclei index was correlated with telomere shortening (P=0.016). The p21WAF1/CIP1 labeling index was significantly higher in cirrhosis than in normal livers (P=0.024) and markedly decreased in low-grade dysplastic nodules, high-grade dysplastic nodules, and hepatocellular carcinomas compared with cirrhosis (P<0.05). The p21WAF1/CIP1 labeling index was associated with telomere length (P<0.001) but not micronuclei index. This study shows that telomere shortening, chromosomal instability, and inactivation of p21WAF1/CIP1 checkpoint function occur in low-grade dysplastic nodules as well as in high-grade dysplastic nodules, and their cooperation is considered to be critical for malignant transformation during hepatitis B virus associated-multistep hepatocarcinogenesis.Keywords: dysplastic nodule, hepatocellular carcinoma, chromosomal instability, p21WAF1/CIP1, telomere, hepatitis B virus
    Modern Pathology 05/2009; 22(8):1121-1131. · 4.79 Impact Factor
  • Source
    Article: Chromosomal instability, telomere shortening, and inactivation of p21(WAF1/CIP1) in dysplastic nodules of hepatitis B virus-associated multistep hepatocarcinogenesis.
    [show abstract] [hide abstract]
    ABSTRACT: Systemic analysis for chromosomal instability and inactivation of cell cycle checkpoints are scarce during hepatocarcinogenesis. We studied 24 patients with chronic B viral cirrhosis including 30 cirrhotic regenerative nodules, 35 low-grade dysplastic nodules, 15 high-grade dysplastic nodules, 7 dysplastic nodules with hepatocellular carcinoma foci, and 18 hepatocellular carcinomas. Eight normal livers were studied as the control group. Telomere length and micronuclei were detected by Southern blot and Feulgen-fast green dyeing technique, respectively, and p21(WAF1/CIP1) expression was studied by immunohistochemistry. Micronuclei >1 per 3000 hepatocytes were found in 17% of low-grade dysplastic nodules, 87% of high-grade dysplastic nodules, and 100% of high-grade dysplastic nodules with hepatocellular carcinoma foci and hepatocellular carcinomas in contrast to those of all normal livers, and 90% of cirrhosis showed no micronuclei. The micronuclei index showed a gradual increase during hepatocarcinogenesis and there was a significant increase between cirrhosis and low-grade dysplastic nodules, low-grade dysplastic nodules and high-grade dysplastic nodules, and high-grade dysplastic nodules and hepatocellular carcinomas. Telomere length showed a gradual shortening during hepatocarcinogenesis and a significant reduction was found in high-grade dysplastic nodules (P=0.024) and hepatocellular carcinomas (P=0.031) compared with normal and cirrhotic livers. The micronuclei index was correlated with telomere shortening (P=0.016). The p21(WAF1/CIP1) labeling index was significantly higher in cirrhosis than in normal livers (P=0.024) and markedly decreased in low-grade dysplastic nodules, high-grade dysplastic nodules, and hepatocellular carcinomas compared with cirrhosis (P<0.05). The p21(WAF1/CIP1) labeling index was associated with telomere length (P<0.001) but not micronuclei index. This study shows that telomere shortening, chromosomal instability, and inactivation of p21(WAF1/CIP1) checkpoint function occur in low-grade dysplastic nodules as well as in high-grade dysplastic nodules, and their cooperation is considered to be critical for malignant transformation during hepatitis B virus associated-multistep hepatocarcinogenesis.
    Modern Pathology 05/2009; 22(8):1121-31. · 4.79 Impact Factor
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    Article: Gastric schwannoma.
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    ABSTRACT: Schwannomas, also known as neurinomas or neurilemmomas, are generally benign, slow-growing neoplasms originating in any nerve that has a Schwann cell sheath. These neoplasms are rare among the spindle cell mesenchymal tumors of the gastrointestinal tract, but develop most commonly in the stomach representing 0.2% of all gastric tumors. We present the case of a 57-year-old female patient with a large schwannoma in the stomach that was palpable in the abdomen. She underwent subtotal gastrectomy under suspicion of gastrointestinal stromal tumor (GIST), but post-operative histopathological and immunohistochemical findings showed a fascicular arrangement of spindle cell with pallisading nuclei, and positive for S-100 protein with negative smooth muscle actin (SMA). These results confirmed schwannoma as the diagnosis.
    Yonsei Medical Journal 01/2009; 49(6):1052-4. · 1.14 Impact Factor
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    Article: Hypofractionated high-dose intensity-modulated radiotherapy (60 Gy at 2.5 Gy per fraction) for recurrent renal cell carcinoma: a case report.
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    ABSTRACT: A patient with renal cell carcinoma (RCC) developed synchronous bone metastasis with metachronous relapses to the bone and renal fossa. The primary lesion was initially removed surgically, and the metastatic bone lesions and locally recurrent tumours were treated by a high-fractional dose and high-total-dose intensity-modulated radiotherapy (IMRT, 60 Gy at 2.5 Gy per fraction) without significant side effects. All the grossly relapsed tumors underwent complete remission (CR) within a short time after IMRT. To date, CR has been maintained for more than two years. This case study reports the successful treatment of radioresistant RCC using a new scheme that involves a fractionation regimen with a high precision radiotherapy.
    Journal of Korean Medical Science 09/2008; 23(4):740-3. · 0.99 Impact Factor
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    Article: Multiple endocrine neoplasia type 1 with multiple leiomyomas linked to a novel mutation in the MEN1 gene.
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    ABSTRACT: Multiple endocrine neoplasia type 1 (MEN1) is an autosomal dominantly inherited syndrome. MEN1 is characterized by the presence of functioning and nonfunctioning tumors or hyperplasia of the pituitary gland, parathyroid glands, and pancreatic islet cells. In addition, MEN1 carriers can have adrenal or thyroid tumors and non-endocrine tumors, such as lipomas, angiofibromas, and leiomyomas. Although leiomyoma is not a major component of MEN1, it is thought to occur more frequently than expected. However, there has been no report of a case of MEN1 with leiomyoma in Korea so far. This report describes a patient with multiple leiomyomas in MEN1. A 50-year-old woman was referred for further evaluation of elevated calcium levels and osteoporosis. Biochemical abnormalities included hypercalcemia with elevated parathyroid hormone. There was hyperprolactinemia with pituitary microadenoma in sella MRI. An abdominal MRI demonstrated adrenal nodules and leiomyomas in the bladder and uterus. Endoscopic ultrasonography demonstrated esophageal leiomyoma and pancreatic islet cell tumor. A subtotal parathyroidectomy with thymectomy was performed. Sequencing of the MEN1 gene in this patient revealed a novel missense mutation (D350V, exon 7). This is the first case of MEN1 accompanied with multiple leiomyomas, parathyroid adenoma, pituitary adenoma, pancreatic tumor, and adrenal tumor.
    Yonsei Medical Journal 09/2008; 49(4):655-61. · 1.14 Impact Factor
  • Article: Staging of extrahepatic cholangiocarcinoma.
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    ABSTRACT: Preoperative staging of extrahepatic cholangiocarcinoma is important in determining the best treatment plan. Several classification systems have been suggested to determine the operability and extent of surgery. Longitudinal tumor extent is especially important in extrahepatic cholangiocarcinoma because operative methods differ depending on the tumor extent. The Bismuth-Corlette classification system provides useful information when planning for surgery. However, this classification system is not adequate for selecting surgical candidates. Anatomic variation of the bile duct and gross morphology of the tumor must be considered simultaneously. Lateral spread of the tumor can be evaluated based on the TNM staging provided by American Joint Committee on Cancer (AJCC). However, there is a potential for ambiguity in the distinction of T1 and T2 cancer from one another. In addition, T stage does not necessarily mean invasiveness. Blumgart T staging is helpful for the assessment of resectability with the consideration of nodal status and distant metastasis as suggested by the AJCC cancer staging system. Computed tomography (CT) and magnetic resonance imaging (MRI) are the primary tools used in the assessment of longitudinal and lateral spread of a tumor when determining respectability. Diagnostic laparoscopy and positron emission tomography (PET) may play additional roles in this regard.
    European Radiology 06/2008; 18(10):2182-95. · 3.22 Impact Factor
  • Article: A case of spleen-preserving laparoscopic distal pancreatectomy and concomitant cholecystectomy in male patient with solid pseudopapillary neoplasm of the pancreas and gallstone.
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    ABSTRACT: Solid pseudopapillary neoplasm is a rare pathologic condition in the pancreas. The origin of this tumor and characteristic biologic behavior are still under investigation. With the advances of laparoscopic surgery, laparoscopic pancreatic surgery has been accepted as a feasible, safe procedure. Especially, laparoscopic distal pancreatectomy is regarded as an appropriate treatment option for benign or borderline malignant pancreatic lesions. In addition, the frequency of spleen-preserving laparoscopic distal pancreatectomy has been increasing owing to embossing the value of the spleen in terms of its immunologic aspects. In this paper, we present a case of a 39-year-old male patient with solid pseudopapillary with (SPN) and a gallstone who successfully underwent laparoscopic distal pancreatectomy with preservation of the spleen, as well as a simultaneous cholecystectomy for the gallstone. To our knowledge, this case may be the first report of the spleen preserving distal pancreatectomy in an adult male patient with SPN.
    Journal of Laparoendoscopic & Advanced Surgical Techniques 05/2008; 18(2):259-65. · 1.40 Impact Factor
  • Article: An obstructing large schwannoma in the esophagus.
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    ABSTRACT: Esophageal schwannoma is very rare neoplasm, which is difficult to diagnose by endoscopy or radiologic evaluations. The diagnosis is not confirmed until immunohistochemical tests are performed after a surgeon has resected the lesion. We present the case of a 65-year-old male patient with an esophageal schwannoma having a palpable neck mass and severe dysphagia. The postoperative pathological findings revealed a strong immunoactivity to S-100 protein but negative activity to smooth muscle actin and C-kit. These results support the characteristics of schwannoma in the tumor.
    Journal of Gastrointestinal Surgery 05/2008; 12(4):761-3. · 2.83 Impact Factor
  • Article: Production of D-tagatose at high temperatures using immobilized Escherichia coli cells expressing L-arabinose isomerase from Thermotoga neapolitana.
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    ABSTRACT: Escherichia coli cells expressing L-arabinose isomerase from Thermotoga neapolitana (TNAI) were immobilized in calcium alginate beads. The resulting cell reactor (2.4 U, t (1/2) = 43 days at 70 degrees C) in a continuous recycling mode at 70 degrees C produced 49 and 38 g D-tagatose/l from 180 and 90 g D-galactose/l, respectively, within 12 h.
    Biotechnology Letters 05/2007; 29(4):569-74. · 1.68 Impact Factor
  • Article: Biomarkers of muscle and cartilage damage and inflammation during a 200 km run.
    Hyo Jeong Kim, Yoon Hee Lee, Chang Keun Kim
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    ABSTRACT: Ultra-marathon running is frequently associated with muscle fibre damage. However, ultra-marathon related information is scarce. The present study evaluated muscle and cartilage biomarkers, and cytokine secretion during a 200 km running event. Venous blood samples from 54 trained male ultra-marathon runners (mean +/- SD, 45.7 +/- 5.1 years). Plasma creatine phosphokinase (CPK), lactate dehydrogenase (LDH), aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate, glucose, high-sensitivity C-reactive protein (Hs-CRP), interleukin-6 (IL-6), TNF- proportional, variant and serum cartilage oligomeric matrix protein (COMP) content were determined before, midway and immediately after the race. CPK increased 90-fold (19-fold at 100 km) from pre-race value and LDH increased 3.7-fold (2.2-fold at 100 km). AST increased 15-fold (5-fold at 100 km) and ALT increased 3.9-fold (2-fold at 100 km). Blood lactate and glucose levels did not change significantly. Hs-CRP increased 23-fold (3-fold at 100 km) and IL-6 increased 121-fold at 100 km, and then remained stable up to 200 km, whereas TNF- proportional, variant did not change significantly. Serum COMP increased 3-fold (1.3-fold at 100 km). Post-run CPK was correlated with LDH (r = 0.62, P < 0.001), Hs-CRP (r = 0.45, P < 0.001), ALT (r = 0.89, P < 0.001), AST (r = 0.97, P < 0.001), and IL-6 (r = 0.61, P < 0.001). The present study demonstrated that blood biomarkers related to muscle and cartilage damage and inflammation were increased during a 200 km run and that this was particularly marked during the second half of the event. Ultra-marathon running clearly has a major impact on muscle and cartilage structures.
    Arbeitsphysiologie 04/2007; 99(4):443-7. · 2.15 Impact Factor
  • Article: Polymorphism of doxazosin mesylate.
    Young-Taek Sohn, Yoon-Hee Lee
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    ABSTRACT: Nine polymorphic modifications of doxazosin mesylate have been obtained by recrystallization in organic solvents under variable conditions. Different polymorphs of doxazosin mesylate were characterized by powder X-ray crystallography diffractometry (PXRD), differential scanning calorimetry (DSC), and thermogravimetric analysis (TG). Transformation of Form 1 and Form 2 was not occurred in three relative humidities (0%, 51%, and 99%) at 20 +/- 0.5 for 30 days.
    Archives of Pharmacal Research 07/2005; 28(6):730-5. · 1.59 Impact Factor
  • Article: Cloning, expression and characterization of L-arabinose isomerase from Thermotoga neapolitana: bioconversion of D-galactose to D-tagatose using the enzyme.
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    ABSTRACT: Gene araA encoding an L-arabinose isomerase (AraA) from the hyperthermophile, Thermotoga neapolitana 5068 was cloned, sequenced, and expressed in Escherichia coli. The gene encoded a polypeptide of 496 residues with a calculated molecular mass of 56677 Da. The deduced amino acid sequence has 94.8% identical amino acids compared with the residues in a putative L-arabinose isomerase of Thermotoga maritima. The recombinant enzyme expressed in E. coli was purified to homogeneity by heat treatment, ion exchange chromatography and gel filtration. The thermophilic enzyme had a maximum activity of L-arabinose isomerization and D-galactose isomerization at 85 degrees C, and required divalent cations such as Co(2+) and Mn(2+) for its activity and thermostability. The apparent K(m) values of the enzyme for L-arabinose and D-galactose were 116 mM (v(max), 119 micromol min(-1) mg(-1)) and 250 mM (v(max), 14.3 micromol min(-1) mg(-1)), respectively, that were determined in the presence of both 1 mM Co(2+) and 1 mM Mn(2+). A 68% conversion of D-galactose to D-tagatose was obtained using the recombinant enzyme at the isomerization temperature of 80 degrees C.
    FEMS Microbiology Letters 07/2002; 212(1):121-6. · 2.04 Impact Factor

Institutions

  • 2012
    • Korea National Sport University
      Seoul, Seoul, South Korea
  • 2011
    • CHA University
      • Department of Pathology
      Seoul, Seoul, South Korea
  • 2009
    • Yonsei University Hospital
      • Surgery
      Seoul, Seoul, South Korea
  • 2008
    • Yonsei University
      • Department of Radiation Oncology
      Seoul, Seoul, South Korea
  • 2005
    • Duksung Women's University
      Seoul, Seoul, South Korea