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Jeong JC, Yoon CH, Jeong CW, Lee YC, Chang YC, Kim CH. Inhibitory Activity ofDrynariae rhizomaExtracts on Cathepsin Having Bone Resorption Activity. Immunopharmacol Immunotoxicol 2004; 26:373-85. [PMID: 15518171 DOI: 10.1081/iph-200026879] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Effects of traditional Korean (Hanbang) medicine, Drynariae rhizoma (DR), on the protease activity of bone loss-initiation in rats and mice were investigated. Ethanol extracts-DR (EE-DR) and water extracts-DR (WE-DR) were identified as potent inhibitor of cathepsins K and L. The original WE-DR inhibits cathepsins K and L with IC50 values of 3.7 microg/ml and 4.5 microg/ml, respectively. EE-DR was more potent than that of WE-DR, because the inhibitions of cathepsin K and L increased to 0.5 microg/ml and 0.8 microg/ml, respectively. The EE-DR was proved to be the most potent. EE-DR was found to be a potent inhibitor of cathepsins K with a Ki value of 5.0 microg/ml for cathepsin K. The activity was increased by 10-fold when the assay is performed in the presence of glutathione at pH 7.0, which favors the formation of a GSH thiolate anion. Thus, it is suggested that this increase in potency is probably due to an enhanced chemical reactivity of the extract mixtures toward the thiolate of the active site of the enzyme. WE-DR exhibited time-dependet inhibition which allowed us to determine the association and dissociation rate constants with cathepsin K. Finally, EE-DR inhibits bone resorption in an in vitro assay involving mouse osteoclasts and bovine bone with an IC50 value of 70 microg/ml. WE-DR represents a new herbal formulation inhibiting cathepsin K and L activity and proteolysis of bone collagen. These results strongly suggest that DR is effective for preventing the development of bone loss induced by cathepsin K. This result also suggested that the DR is effective for bone resorptive action in bone cells.
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Jeong JC, Kang SK, Yoon CH, Seo YJ, Hwang CW, Ko JH, Lee YC, Chang YC, Kim CH. Inhibitory effects of Bombusae concretio Salicea on neuronal secretion of Alzheimer's beta-amyloid peptides, a neurodegenerative peptide. Neurochem Res 2004; 28:1785-92. [PMID: 14649718 DOI: 10.1023/a:1026155321328] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Alzheimer's disease (AD) is characterized by the age-related deposition of beta-amyloid (A beta) 40/42 peptide aggregates in vulnerable brain regions. Multiple levels of evidence implicate a central role for A beta in the pathophysiology of AD. A beta is generated by the regulated cleavage of a = 700 amino acid A beta precursor protein (betaAPP). Full-length betaAPP can undergo proteolytic cleavage either within the A beta domain to generate secreted sbetaAPP alpha or at the N-terminal and C-terminal domain(s) of A beta to generate amyloidogenic A beta peptides. Several epidemiological studies have reported that estrogen replacement therapy protects against the development of AD in postmenopausal women. The aim of this study was to elucidate the antioxidant neuroprotective mechanism of Bombusae concretio Salicea (BC). BC was effective protectants against oxidative glutamate toxicity in the murine neuroblastoma cells (N2a) and human neuroblastoma cells (SK-N-MC). BC exhibited similar protective properties against oxidative glutamate toxicity and H2O2 toxicity. BC exhibited an antioxidant activity at approximately 20 microg/ml. BC of 5 microg/ml was ineffective in preventing the oxidative modification of LDL. The half-maximal effective concentration for BC was 16 microg/ml. These results suggested that BC supplementation in elderly men may be protective in the treatment of Alzheimer's disease (AD). We report here that treatment with BC increases the secretion of the nonamyloidogenic APP fragment, sbetaAPP alpha and decreases the secretion of A beta peptides from N2a cells and rat primary cerebrocortical neurons. These results raise the possibility that BC supplementation in elderly men may be protective in the treatment of AD.
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Seo GT, Lee TS, Kim JT, Yoon CH, Park HG, Hong SC. Organic and detergent degradation in combined O3/UF for domestic laundry wastewater reclamation. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2004; 50:331-336. [PMID: 15537022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
This paper focuses on the evaluation of organic and detergent degradation in a combined Ozone/UF system for domestic laundry wastewater reclamation. Formation of by-product was investigated by GC/MS for the reclaimed water. Ozone was injected into the raw wastewater in a 10 L contact tank and the wastewater was circulated through the membrane module for inner pressurized cross-flow filtration. The concentrate was returned back to the contact tank. The membrane used in this experiment was hollow fiber polysulfone UF membrane with MWCO 10,000. It has an effective filtration area of 0.06 m2. The experiment was carried out with intermittent ozone injection, 5 min injection and 10 min idling. Ozone was dosed at the concentration of 1.5 mg/L. The flux of the UF could be maintained at 0.24 m/d under filtration pressure 40-45 kPa and water temperature, 20-22 degrees C. The organic removal efficiency by the system was 90% in terms of COD. Ozone was considerably effective to degrade organics in the wastewater. Molecular weight of organics in the raw waste was mostly greater than 10,000 (72% of 950 mgCOD/L). However 86% of effluent COD (94-100 mg/L) was composed of organics smaller than MWCO 500 by ozone injection. No harmful by-products by ozone contact were detected from the analysis of treated water using GC/MS. It was identified that residual organics in the treated water were 1,1'-Oxybisbenzene, Octadecanoic acid, Squalene and Benzenmethanol, etc., which were additives contained originally in the detergent. Consequently the reclaimed water quality could be estimated safe enough to recycle for the rinsing cycle in a washing machine.
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Yoon CH, Goo HW, Kim EA, Kim KS, Pi SY. Sonographic windsock sign of a duodenal web. Pediatr Radiol 2001; 31:856-7. [PMID: 11727020 DOI: 10.1007/s002470100005] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/18/2000] [Accepted: 07/05/2001] [Indexed: 11/25/2022]
Abstract
We report a neonate with a duodenal web demonstrating the windsock appearance on US. In neonates, duodenal web is rare and its windsock appearance is also rarely seen. The windsock sign of duodenal web has been a well-known finding on upper gastrointestinal series. The corresponding windsock appearance may be demonstrated on US. Duodenal web can, therefore, be accurately diagnosed by identifying the sonographic windsock sign even in neonates.
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Kim DS, Yoon CH, Lee SJ, Park SY, Yoo HJ, Cho HJ. Changes in voltage-gated calcium channel alpha(1) gene expression in rat dorsal root ganglia following peripheral nerve injury. BRAIN RESEARCH. MOLECULAR BRAIN RESEARCH 2001; 96:151-6. [PMID: 11731020 DOI: 10.1016/s0169-328x(01)00285-6] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Although an increase in the excitability and ectopic spontaneous discharge (ESD) of primary sensory neurons can lead to abnormal burst activity, which is associated with neuropathic pain, the underlying molecular mechanisms are not fully understood. To investigate the relationship between these electrical abnormalities in injured neurons and voltage-gated calcium channel (VGCC) gene expression, reverse transcription-polymerase chain reaction (RT-PCR) was used to monitor the expression of the VGCC alpha(1) gene in the dorsal root ganglion (DRG) following chronic constriction injury (CCI) and axotomy of the rat sciatic nerve. Electrophoresis of the RT-PCR products showed the presence of multiple types of VGCC alpha(1) transcripts with various levels of basal expression in lumbar 4, 5, and 6 DRGs. CCI decreased alpha(1C), alpha(1D), alpha(1H), and alpha(1I) mRNA expression at 7 days in the ipsilateral DRG, to approximately 34-50% of the contralateral side. The same transcripts were repressed 7 days after sciatic axotomy and their reduction levels proved similar to those of CCI. Considering that changes of the intracellular calcium concentration modify the maintenance of ESD in injured DRG, these results suggest that the downregulation of alpha(1C), alpha(1D), alpha(1H) and alpha(1I) subunit gene expression in the rat DRG following peripheral nerve injury may contribute to the production of ESD associated with damaged nerves.
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Park HS, Kim YK, Yoon CH. Various applications of titanium mesh screen implant to orbital wall fractures. J Craniofac Surg 2001; 12:555-60. [PMID: 11711822 DOI: 10.1097/00001665-200111000-00010] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
As the number of high velocity injuries increases, orbital wall fractures that involve other facial bone fractures, especially those showing multiple crushed fractures have become increasingly common. However, owing to its complex anatomic structure, our inability to visualize details and relatively thin orbital wall, corrective restorations and fixations are very difficult. Recently several reports have claimed good results using titanium implants to repair orbital fracture. Over a period of 36 months, Titanium mesh screen 1.0 (SYNTHES) were applied to the repair of orbital fracture in various ways, taking 39 examples of orbital wall fracture patients requiring operating treatment. A titanium mesh screen 1.0 was used either as an onlay implant after it was shaped to fit the anatomical shape of the fracture portion, or as cover implant to fix bony pieces after repairing a severely crushed fracture on the orbital rim or maxillary wall segments. 1.3-mm micro-screws were used to fix the titanium mesh screen when needed. The titanium mesh screen 1.0 was rigid, yet malleable enough to get the desired shape. It could be folded and screwed easily, and was also easy for follow-up with fewer artifacts on the CT findings. Therefore, we could restore and fix much easier and faster even crushed tiny bony pieces without loss and achieve more accurate three-dimensional anatomical reconstruction of orbital wall fracture.
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Yoon CH, Zaworotko MJ, Moulton B, Jung KW. Regio- and stereocontrol elements in Rh(II)-catalyzed intramolecular C-H insertion of alpha-diazo-alpha-(phenylsulfonyl)acetamides. Org Lett 2001; 3:3539-42. [PMID: 11678702 DOI: 10.1021/ol016647l] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
[reaction: see text]. Intramolecular C-H insertion reaction of alpha-diazo-alpha-(phenylsulfonyl)acetamides proceeded with high regio- and stereoselectivities to afford highly functionalized gamma-lactams predominantly or exclusively. The high regioselectivity was attributed to the use of the phenylsulfonyl moiety, which altered electron density at the carbenoid center and exerted a steric effect during the insertion reaction. Also described herein are three control elements to determine regioselectivity, which are amide conformational, stereoelectronic, and substituent effects.
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Goo HW, Kim HJ, Song KS, Kim EA, Kim KS, Yoon CH, Pi SY. Using edge enhancement to identify subtle findings on soft-copy neonatal chest radiographs. AJR Am J Roentgenol 2001; 177:437-40. [PMID: 11461878 DOI: 10.2214/ajr.177.2.1770437] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
OBJECTIVE The purpose of this study was to evaluate whether edge enhancement could improve the visibility of subtle findings on soft copies of neonatal chest radiographs. MATERIALS AND METHODS Two radiologists reviewed 82 soft-copy neonatal chest radiographs before and after the application of edge enhancement on our picture archiving and communication system (PACS). The visibility of a pneumothorax (n = 22), central venous catheter (n = 32), umbilical arterial catheter (n = 36), endotracheal tube (n = 40), and normal anatomic structures (the minor fissure, anterior segmental bronchus of the right upper lobe, and aortic arch, n = 57) was evaluated. Six of 22 soft-copy images depicting a pneumothorax were excluded from the evaluation of image quality either because of the large size of the pneumothorax itself (n = 7) or because of the lack of confirmatory evidence that would have been provided by an additional lateral decubitus (n = 6) or cross-table lateral radiograph (n = 3). Image quality was evaluated by visual grading analysis. RESULTS The visibility of a pneumothorax (p < 0.01), vascular catheters (p < 0.001), the minor fissure (p < 0.001), and the anterior segmental bronchus of the right upper lobe (p < 0.001) improved significantly after applying edge enhancement to soft copies of neonatal chest radiographs, whereas the visibility of the aortic arch did not improve. Evaluations of the improvements in the visibility of the endotracheal tube were inconsistent. CONCLUSION Application of edge enhancement to soft copies of neonatal chest radiographs helps radiologists to identify small pneumothoraces, vascular catheters, and delicate normal structures, thereby improving the detection of subtle chest findings in the neonatal intensive care unit.
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Jeong JC, Hwang WM, Yoon CH, Kim YK. Salviae radix extract prevents cisplatin-induced acute renal failure in rabbits. Nephron Clin Pract 2001; 88:241-6. [PMID: 11423755 DOI: 10.1159/000045996] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
The present study was carried out to determine if salviae radix extract (SRE) exerts a beneficial effect against cisplatin-induced renal failure in rabbits. Rabbits were pretreated with SRE orally for 7 days, followed by cisplatin injection (5 mg/kg i.p.). Cisplatin injection caused a reduction in GFR, which was accompanied by an increase in serum creatinine levels. The fractional Na+ excretion was increased by cisplatin injection. PAH uptake by renal cortical slices was inhibited by the administration of cisplatin. Such changes were prevented by SRE pretreatment. Cisplatin injection increased lipid peroxidation, which was prevented by SRE pretreatment. The protective effect of SRE was supported by morphological studies. Cisplatin injection reduced renal blood flow that was not affected by SRE pretreatment. Cisplatin treatment in vitro in renal cortical slices increased LDH release and lipid peroxidation, which were prevented by 0.05% SRE. These results indicate that lipid peroxidation plays a critical role in cisplatin-induced acute renal failure. SRE exerts a protective effect against renal cell injury induced by cisplatin, and its effect may be attributed to its antioxidant action. However, the underlying mechanism by which SRE has antioxidant action remains to be defined.
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Yoon CH, Cho SH, Kim SH, Ha SR. Catalytic wet air oxidation of p-nitrophenol (PNP) aqueous solution using multi-component heterogeneous catalysts. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2001; 43:229-236. [PMID: 11380184] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
This study investigated the decomposition of high strength p-nitrophenol (PNP) of 2,000 mg/l (3,400 mg of COD/1,250 mg of TOC) by catalytic wet air oxidation. Multi-component heterogeneous catalysts were used as catalysts for this purpose. The study results using a batch reactor showed that catalyst "D" (Mn-Ce-Zr 22.4 g plus CuSO4 1.0 g; Mn-Ce-Zr-Cu [CuSO4]) was more effective (56-74%) than catalyst "A" (Mn-Ce-Zr 22.4 g) under the given conditions (O2 partial pressure of 1.0 MPa; temperature of 170-190 degrees C; 30 min of reaction time). The best result was obtained when 2 g of Mn-Ce-Zr-Cu [CuSO4] was used per 1L of PNP aqueous solution. COD and TOC removal efficiencies were 18% and 23% without catalysts during 20 min of reaction at 190 degrees C. They were improved to 79% and 71% with 2 g/L of Mn-Ce-Zr-Cu [CuSO4] under the same conditions. The ratio of BOD5/COD was measured to evaluate biodegradability. It was 0.05 without catalyst and increased to 0.33 with 2 g/L of Mn-Ce-Zr-Cu [CuSO4] for 20 min of reaction.
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Kim HJ, Lee WH, Yoon CH, Jeong JC, Nam KS, Kim HM, Choo YK, Lee MC, Kim CH. Bombycis corpus extract prevents amyloid-beta-induced cytotoxicity and protects superoxide dismutase activity in cultured rat astrocytes. Pharmacol Res 2001; 43:11-6. [PMID: 11207060 DOI: 10.1006/phrs.2000.0746] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Bombycis corpus(BC) or Bombyx Batryticatus, a batryticated silkworm and white-stiff silkworm, is a drug consisting of the dried larva of silkworm, Mobyz mori L., dead and stiffened due to the infection of Beauveria (Bals.) Vuill. In the present study, we have examined the protective effect of the water extracts against Amyloid- beta(A beta) 25-35 peptide-induced cytotoxicity by microscopic observation and LDH assay, and its action on antioxidative enzymes using cultured astrocyte cells. A beta 25-35-induced cell death was protected by the application of water extract of BC in a dose-dependent manner, and concentrations of 10(-6)to 10(-7)g ml(-1)showed a significant effect compared to exposure of A beta 25-35 alone. When antioxidative enzyme activities such as catalase, superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and glutathione-S transferase (GST) were assayed after A beta 25-35 treatment, most enzyme activities were decreased in a similar fashion. BC treatment of A beta 25-35-treated astrocytes did not affect the enzyme activities of catalase, GSH-Px and GST. However, only SOD activity was enhanced by BC treatment and this may result from the potentiation of the antioxidative ability of BC. The protective effect of BC against cytotoxicity induced by Abeta 25-35 strongly indicates that BC could be a protective agent for free radical generating compounds, and that Abeta 25-35 is not only a potent lipid peroxide inducer, but can also cause changes in antioxidative enzymes. From the results, it was concluded that BC has a protective effect against Abeta -induced cytotoxicity in cultured astrocyte cells through the inhibition of lipid peroxidation and protection of antioxidative enzymes.
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Abstract
PURPOSE To assess the feasibility and effectiveness of ultrasonography (US)-guided pneumatic reduction of intussusception in children. MATERIALS AND METHODS The study group consisted of 49 consecutive patients (aged 2 months to 7 years; 36 boys, 13 girls) who underwent 52 reductions of intussusception during 9 months. Intussusception was diagnosed in all patients with the known US criteria, and all patients underwent a US-guided pneumatic reduction attempt wholly within the US examination room. A pressure of 60 mm Hg was maintained for 30 seconds, with US guidance. The procedure was considered to be successful when US showed the disappearance of the intussusceptum and the edematous terminal ileum with an abrupt transition into the normal proximal ileum. When the intussusception was not reduced, the procedure was repeated, with pressure increased to 120 mm Hg. RESULTS The overall success rate of US-guided pneumatic reduction was 92% (48 of 52 reductions), with no immediate recurrence. Of the two patients who had intussusceptions that were irreducible, one had residual ileoileal intussusception at surgery, and the other had an ileal polyp as a lead point. Perforation occurred in two (4%) of 52 cases; one patient underwent right hemicolectomy due to bowel necrosis and had a pinpoint perforation in the normal proximal transverse colon, and the other underwent manual reduction of ileoileocolic intussusception, with microperforation in the proximal transverse colon. CONCLUSION US-guided pneumatic reduction seems to be a feasible and effective method for the treatment of intussusception in children because of its radiation-sparing effect and high success rate.
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Cho YS, Song HY, Ko GY, Yoon CH, Ahn HS, Yoon HK, Sung KB. Congenital lacrimal system obstruction: treatment with balloon dilation. J Vasc Interv Radiol 2000; 11:1319-24. [PMID: 11099243 DOI: 10.1016/s1051-0443(07)61309-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
PURPOSE To evaluate the safety and effectiveness of balloon dilation for the treatment of congenital lacrimal system obstruction. MATERIALS AND METHODS Fluoroscopically guided balloon dilation was attempted in 20 eyes of 16 patients with an age range of 12-78 months (mean, 33 mo) for congenital lacrimal system obstruction. Fifteen eyes had complete obstruction at the valve of Hasner, three eyes had completely obstruction at the junction between the lacrimal sac and the nasolacrimal duct, and two eyes had partial obstruction at the nasolacrimal duct. Under general anesthesia, a ball-tipped guide wire was introduced through the superior punctum into the inferior meatus of the nasal cavity and pulled out through the naris with use of a hook. A deflated 3-mm-diameter balloon catheter was then advanced in a retrograde direction and the balloon was dilated. Every patient underwent an ophthalmic evaluation before the procedure and was scheduled to be followed with office examination at 1, 3, and 6 months after the procedure. RESULTS There were no major complications. "Technical success" was defined as free passage of contrast medium through the entire lacrimal system to the nasal cavity. The procedure failed in one eye. After balloon dilation, all 19 eyes in which technical success was achieved showed improvement of epiphora. During the follow-up period of 2-33 months (mean, 16 mo), all eyes maintained improvement of epiphora and needed no further treatment. CONCLUSION Balloon dilation is a safe and effective therapeutic technique for the treatment of congenital lacrimal system obstruction.
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Yoon CH, Chang C, Hopper NA, Lesa GM, Sternberg PW. Requirements of multiple domains of SLI-1, a Caenorhabditis elegans homologue of c-Cbl, and an inhibitory tyrosine in LET-23 in regulating vulval differentiation. Mol Biol Cell 2000; 11:4019-31. [PMID: 11071924 PMCID: PMC15054 DOI: 10.1091/mbc.11.11.4019] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
SLI-1, a Caenorhabditis elegans homologue of the proto-oncogene product c-Cbl, is a negative regulator of LET-23-mediated vulval differentiation. Lack of SLI-1 activity can compensate for decreased function of the LET-23 epidermal growth factor receptor, the SEM-5 adaptor, but not the LET-60 RAS, suggesting that SLI-1 acts before RAS activation. SLI-1 and c-Cbl comprise an N-terminal region (termed SLI-1:N/Cbl-N, containing a four-helix bundle, an EF hand calcium-binding domain, and a divergent SH2 domain) followed by a RING finger domain and a proline-rich C-terminus. In a transgenic functional assay, the proline-rich C-terminal domain is not essential for sli-1(+) function. A protein lacking the SH2 and RING finger domains has no activity, but a chimeric protein with the SH2 and RING finger domains of SLI-1 replaced by the equivalent domains of c-Cbl has activity. The RING finger domain of c-Cbl has been shown recently to enhance ubiquitination of active RTKs by acting as an E3 ubiquitin-protein ligase. We find that the RING finger domain of SLI-1 is partially dispensable. Further, we identify an inhibitory tyrosine of LET-23 requiring sli-1(+) for its effects: removal of this tyrosine closely mimics the loss of sli-1 but not of another negative regulator, ark-1. Thus, we suggest that this inhibitory tyrosine mediates its effects through SLI-1, which in turn inhibits signaling upstream of LET-60 RAS in a manner not wholly dependent on the ubiquitin-ligase domain.
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Shin JH, Yoon CH, Cho KS, Lim SD, Kim EA, Kim KS, Pi SY, Auh YH. Fetus-in-fetu in the scrotal sac of a newborn infant: imaging, surgical and pathological findings. Eur Radiol 1999; 9:945-7. [PMID: 10369997 DOI: 10.1007/s003300050773] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
We report a case of fetus-in-fetu located in the scrotal sac of a newborn male infant. Plain radiography (including specimen radiography), ultrasonography and MRI clearly demonstrated vertebral column, ribs, skull, pelvic bones, femurs and a portion of tibiae and humeri. The diagnosis was confirmed by pathological examination.
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Abstract
To investigate the prevalence and type of congenital inverted nipple, and realizing that the condition is a disease for which treatment is necessary, 1,625 unmarried women aged between 19 and 26 were physically examined and responded to questions about inverted nipple. Fifty-three of 1,625 subjects (3.26%) presented with this malformation, and it was found in 3.05% of the 3,250 nipples examined. In 46 of the 53 (86.79%), the condition was bilateral, and in 7 (13.21%), it was unilateral. In such cases, inversion was found on the right side in two subjects and on the left side in five. Of the total number of congenital inverted nipples, 96.23% were umbilicated and 3.77% were invaginated. Nine of the 53 subjects with inverted nipple considered that the condition should be corrected. Prior to counseling and possible surgery, the medical practitioner must carefully consider all available information, and the data contained in this report may thus be useful.
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Park ST, Yoon CH, Sung KB, Yoon HK, Goo DE, Kim KS, Pi SY, Auh YH. Pulmonary sequestration in a newborn infant: treatment with arterial embolization. J Vasc Interv Radiol 1998; 9:648-50. [PMID: 9684838 DOI: 10.1016/s1051-0443(98)70337-9] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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Jeong YK, Ha HK, Yoon CH, Gong G, Kim PN, Lee MG, Min YI, Auh YH. Gastrointestinal involvement in Henoch-Schönlein syndrome: CT findings. AJR Am J Roentgenol 1997; 168:965-8. [PMID: 9124151 DOI: 10.2214/ajr.168.4.9124151] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
OBJECTIVE The purpose of this study was to describe the CT features of gastrointestinal involvement in seven patients with Henoch-Schönlein syndrome. CONCLUSION Although the incidence of Henoch-Schönlein syndrome is low, it should be considered when CT scans show multifocal areas of bowel-wall thickening, mesenteric edema, vascular engorgement, and nonspecific lymphadenopathy. It should be considered especially in young patients with acute gastrointestinal symptoms.
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Nakamoto M, Cheng HJ, Friedman GC, McLaughlin T, Hansen MJ, Yoon CH, O'Leary DD, Flanagan JG. Topographically specific effects of ELF-1 on retinal axon guidance in vitro and retinal axon mapping in vivo. Cell 1996; 86:755-66. [PMID: 8797822 DOI: 10.1016/s0092-8674(00)80150-6] [Citation(s) in RCA: 361] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Topographic maps, which maintain the spatial order of neurons in the order of their axonal connections, are found throughout the nervous system. In the visual retinotectal projection, ELF-1, a ligand in the tectum, and its receptors in the retina show complementary gradients in expression and binding, indicating they may be positional labels for map development. Here we show that ELF-1 acts as a repellent axon guidance factor in vitro. In vivo, when the tectal ELF-1 pattern is modified by retroviral overexpression, retinal axons avoid ectopic ELF-1 patches and map to abnormally anterior positions. All these effects were seen on axons from temporal but not nasal retina, indicating that ELF-1 could determine nasal versus temporal retinotectal specificity, and providing a direct demonstration of a cell recognition molecule with topographically specific effects on neural map development.
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Yoon CH, Lee J, Jongeward GD, Sternberg PW. Similarity of sli-1, a regulator of vulval development in C. elegans, to the mammalian proto-oncogene c-cbl. Science 1995; 269:1102-5. [PMID: 7652556 DOI: 10.1126/science.7652556] [Citation(s) in RCA: 244] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Vulval induction during Caenorhabditis elegans development is mediated by LET-23, a homolog of the mammalian epidermal growth factor receptor tyrosine kinase. The sli-1 gene is a negative regulator of LET-23 and is shown here to encode a protein similar to c-Cbl, a mammalian proto-oncoprotein. SLI-1 and c-Cbl share approximately 55 percent amino acid identity over a stretch of 390 residues, which includes a C3HC4 zinc-binding motif known as the RING finger, and multiple consensus binding sites for Src homology 3 (SH3) domains. SLI-1 and c-Cbl may define a new class of proteins that modify receptor tyrosine kinase-mediated signal transduction.
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Sternberg PW, Yoon CH, Lee J, Jongeward GD, Kayne PS, Katz WS, Lesa G, Liu J, Golden A, Huang LS. Molecular genetics of proto-oncogenes and candidate tumor suppressors in Caenorhabditis elegans. COLD SPRING HARBOR SYMPOSIA ON QUANTITATIVE BIOLOGY 1994; 59:155-63. [PMID: 7587065 DOI: 10.1101/sqb.1994.059.01.019] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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Imaida K, Furihata C, Tatematsu M, Yoon CH, Furukawa F, Uneyama C, Takahashi M, Ito N, Hayashi Y. Immunohistochemical and biochemical identification of pepsinogen isozymes in the hamster lungs: induction by polychlorinated biphenyls. Toxicol Pathol 1991; 19:230-6. [PMID: 1780640 DOI: 10.1177/019262339101900305] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Pepsinogens are acid protease enzymes of pepsin usually found in gastric mucosa. In the present study, we demonstrated the presence of pepsinogen isozymes in male Syrian golden hamster lung tissues by a combined immunohistochemical and biochemical approach. Immunohistochemically, using rat pepsinogen 1 antibody, pepsinogen positive cells were observed mainly in the epithelia of the terminal bronchioles. They demonstrated morphological features of Clara cells. The pepsinogen isozyme pattern of lung tissue determined by polyacrylamide gel electrophoresis was similar to that of stomach mucosa. Treatment of hamsters with polychlorinated biphenyls at a dose of 500 mg/kg body weight ip caused a 2.8-fold increase in pepsinogen content (p less than 0.01) as well as increase in numbers of pepsinogen positive cells in the lung.
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Peterson JS, deGroot CT, Yoon CH. Five new mutations in the Syrian hamster: furloss, fur-deficiency, juvenile gray, ashen, and quaking. J Hered 1981; 72:445-6. [PMID: 7334205 DOI: 10.1093/oxfordjournals.jhered.a109557] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Five new mutations in the Syrian hamster are described: furloss, a simple recessive trait affecting the quality of hair; fur-deficiency, a simple recessive trait affecting the quantity of hair and longevity; juvenile gray, a simple recessive trait affecting coat color and body size; ashen, a semidominant trait affecting both coat color and quantity of hair; and quaking, a simple recessive trait affecting motor activity. Gene symbols, fs, Rfd, jg, A, and q are proposed for these mutations.
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