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Lee DK, Han JK, Kim TK, Choi BI. Neoplasms containing normal hepatic vessels: imaging features. ABDOMINAL IMAGING 2000; 25:602-6. [PMID: 11029092 DOI: 10.1007/s002610000049] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND We investigated the incidence and imaging features of hepatic neoplasms containing normal hepatic vessels. METHODS Among 3183 patients with various hepatic neoplasms, we found nine patients with normal hepatic vessels traversing hepatic neoplasms. The presence of mass effect on the vessel traversing hepatic neoplasms was evaluated. Other suggestive findings of neoplasms such as altered hepatic contour, portal vein thrombosis, mass effect on extratumoral vessel, and bile duct dilatation were analyzed. RESULTS Thirteen hepatic vessels (nine hepatic veins and four portal veins) extended through hepatic neoplasms in nine patients. Undisturbed hepatic vessels within the neoplasms were found in five patients with either primary or metastatic hepatic neoplasm. In one patient with undisturbed hepatic vessels within the neoplasm, there were no associated abnormal findings such as biliary dilatation, change of hepatic contour, or any changes involving the vessels external to neoplasms. CONCLUSION Although rare, various primary and secondary hepatic neoplasms can have normal hepatic vessels passing through them without mass effect. However, correct diagnosis in most neoplasms would be possible with careful examination of associated findings.
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Kim HS, Lee DK, Baik SK, Kim JM, Kwon SO, Kim DS, Cho MY. Endoscopic mucosal resection with a ligation device for early gastric cancer and precancerous lesions: comparison of its therapeutic efficacy with surgical resection. Yonsei Med J 2000; 41:577-83. [PMID: 11079617 DOI: 10.3349/ymj.2000.41.5.577] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
Endoscopic mucosal resection with a ligation device (EMR-L) has become important in the curative treatment of precancerous lesions and early gastric cancers (EGCs), but little is known of the long-term efficacy and survival rates of EMR-L compared with surgical resection. We analyzed the therapeutic efficacy and safety of EMR-L in cases of EGC and precancerous lesions and compared the results of EMR-L with those of gastrectomy in patients with EGC over the same periods. EMR-L was performed on 20 EGCs and 54 precancerous lesions including tubular adenomas with or without severe dysplasias in 74 patients. Macroscopic type, size and location of the lesion were determined by endoscope, and the depth of invasion in EGCs was determined by endoscopic ultrasonography and confirmed by pathologic examination of the resected specimens. All the EGC cases were endoscopically followed up for at least 18 months (range, 18-66 months). Patients were selected that underwent subtotal gastrectomy and the survival rates were compared with those that underwent EMR-L. Complete resection was made in a single EMR-L treatment session in 61 cases (82.4%; 91.5%, were precancerous lesions and 65% were EGCs). After a repeat trial of EMR-L, the total rate of complete resection of precancerous lesions and EGCs was 92.6% and 85.0%, respectively. The survival rate of EGCs showed that complete resection by EMR-L resulted in 2 and 5 year survival rates of 100% and 95%, which are comparable to those of surgery (100% and 100%). This study suggests that EMR-L is a technically simple, minimally invasive and highly safe and effective treatment modality for selective EGCs, and offers an alternative to surgical treatment.
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Shin JH, Lee JS, Choi SH, Lee DK, Nam H, Cha GS. A planar pCO2 sensor with enhanced electrochemical properties. Anal Chem 2000; 72:4468-73. [PMID: 11008785 DOI: 10.1021/ac000427o] [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: 11/30/2022]
Abstract
To develop planar microchemical pCO2 sensing devices with improved electrochemical properties, we combined two advanced technologies. One is a differential sensor arrangement to simplify the microfabrication procedure by employing pH-sensitive gas-permeable membranes, and the other is the use of an enzyme (carbonic anhydrase) to shorten total measurement time by accelerating the rate of CO2 hydration. The adhesion of the polyurethane-matrix gas-permeable membrane is enhanced significantly by incorporating a silanizing reagent (silicon tetrachloride), improving the stability and extending sensor lifetime. The proposed differential pCO2 microelectrodes exhibited significantly improved performance in their preconditioning period, response and recovery times, stability, response slope, and lifetime.
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Yang SK, Hong WS, Min YI, Kim HY, Yoo JY, Rhee PL, Rhee JC, Chang DK, Song IS, Jung SA, Park EB, Yoo HM, Lee DK, Kim YK. Incidence and prevalence of ulcerative colitis in the Songpa-Kangdong District, Seoul, Korea, 1986-1997. J Gastroenterol Hepatol 2000; 15:1037-42. [PMID: 11059934 DOI: 10.1046/j.1440-1746.2000.02252.x] [Citation(s) in RCA: 141] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND AND AIMS Ulcerative colitis (UC) is regarded as a rare disease in developing countries, but accurate data are generally lacking. We performed the present study to evaluate the incidence and prevalence of UC in Korea. METHODS A retrospective study was performed from 1986 to 1997 in the Songpa-Kangdong district of Seoul, Korea. To recruit UC patients as completely as possible, multiple information sources including all medical facilities in the study area and three referral centres located nearby, but outside the study area were used. The incidence and prevalence rates were adjusted using the 1997 Korean population statistics. RESULTS During the study period, a total of 94 incident cases were identified, for an adjusted mean annual incidence rate of 0.68 per 100,000 inhabitants. On 31 December 1997, 91 patients with UC lived in the study area, giving an adjusted prevalence rate of 7.57 per 100,000 inhabitants. By using the Poisson regression analysis, the annual incidence rate increased significantly from 0.20 per 100,000 inhabitants in 1986-1988 to 1.23 per 100,000 inhabitants in 1995-1997 (P < 0.005). Patient age at diagnosis, the interval from onset of symptoms to diagnosis, and the disease extent at diagnosis were fairly constant throughout the study period. CONCLUSIONS The incidence and prevalence of UC in our study area are still low compared with those of Western countries, but the incidence rate is steadily increasing.
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Hwang K, Lee DK, Lee CJ, Lee SI. Pneumosinus dilatans multiplex, mental retardation, and facial deformity. J Craniofac Surg 2000; 11:487-90. [PMID: 11314069 DOI: 10.1097/00001665-200011050-00008] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Pneumosinus dilatans is a term used to describe enlargement of one or more paranasal sinuses without radiological evidence of localized bone destruction, hyperostosis, or mucous-membrane thickening. To date, many cases have been reported that involved frontal, ethmoid, sphenoid, and maxillary sinus. However, no case has been reported that involved all paranasal sinuses. Our case involved mastoid air cells as well as all paranasal sinuses. It is named pneumosinus dilatans multiplex by us. This is the first case to be reported in English literature that has this syndromic condition of pneumosinus dilatans multiplex, mental retardation, and facial deformity.
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Lee DK. Predation efficacy of the fish muddy loach, Misgurnus mizolepis, against Aedes and Culex mosquitoes in laboratory and small rice plots. JOURNAL OF THE AMERICAN MOSQUITO CONTROL ASSOCIATION 2000; 16:258-261. [PMID: 11081657] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Assessments of the biological control potential of muddy loaches, Misgurnus mizolepis, were conducted against Aedes togoi, Culex pipiens pallens, and Culex inatomii larvae both in the laboratory and in small rice plots in Pusan, Korea, from June to September 1997. Medium-sized fish consumed almost all of 500 3rd-stage larvae of Cx. pipiens pallens offered daily in the laboratory. Predation by the fish at release rates of 1, 2, 4, 8, and 16 fish per plot resulted in 1,004, 1,197, 1,198, 1,200, and 1,200 larvae of Ae. togoi consumed in 12 h, respectively, when each 1,200 3rd-stage larvae were given in the 1-m2 small rice plots. The average numbers of larvae eaten after introduction of the fish were 1,121.8 larvae in 24 h and 1,195.8 larvae in 36 h. Muddy loaches showed slightly higher predation rates on Cx. pipiens pallens and Culex inatomii larvae than on larvae of Ae. togoi. Therefore, M. mizolepis might be an efficient biological control agent against mosquito species in rice fields.
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Liu Y, Lam K, Tang YJ, Gumerlock PH, Lee DK, Kim MH, Lee SP, Silva J, Leung JW. Anaerobic bacteria and intrahepatic stones: detections of Clostridium sp. and Bacteroides fragilis. Chin Med J (Engl) 2000; 113:858-61. [PMID: 11776087] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023] Open
Abstract
OBJECTIVE To detect anaerobic bacteria Clostridium sp. and Bacteroides fragilis in intrahepatic stones by molecular genetic method. METHODS DNA was extracted from 59 stone samples and subjected to polymerase chain reaction (PCR) amplification targeting the 16S rRNA gene of Clostridium sp. and the glutamine synthetase gene of Bacteroides fragilis. Single-strand conformational polymorphism (SSCP) analysis was performed to identify the Clostridium sp. RESULTS 16S rRNA gene sequences for Clostridium sp. were identified in 49 stones (83%, 49/59). The two most common groups were detected in 19 (41%) and 17 (37%) of the 46 samples using SSPC analysis, and 25/59 (42%) stones were tested positive for Bacteroides fragilis. CONCLUSIONS Anaerobes such as Clostridium sp. and Bacteroides fragilis present in intrahepatic stones and may play a role in stone formation. PCR is a useful technique to detect fastidious pathogens, which are difficult to culture. SSCP of PCR products is a rapid method in differentiating bacterial species.
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Slassi A, Edwards L, O'Brien A, Meng CQ, Xin T, Seto C, Lee DK, MacLean N, Hynd D, Chen C, Wang H, Kamboj R, Rakhit S. 5-Alkyltryptamine derivatives as highly selective and potent 5-HT1D receptor agonists. Bioorg Med Chem Lett 2000; 10:1707-9. [PMID: 10937729 DOI: 10.1016/s0960-894x(00)00322-x] [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]
Abstract
A series of 5-alkyltryptamines (6) and the corresponding conformationally constrained analogues (8) have been synthesized. The structure activity relationships (SAR) at the 5-position of the indole skeleton and the ethylamine side chain have been studied. Functional activities were assessed using isolated rabbit saphenous vein. Potent, selective ligands were found (6e, Ki 2.5 nM, 5-HT1B/5-HT1D 125-fold) that have potential for treating acute migraine.
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Hahn SE, Yu M, Tong S, Geisterfer-Lowrance AA, Sindrey D, Lee DK. Development of an In Vitro Screening Assay for Compounds that Increase Bone Formation. JOURNAL OF BIOMOLECULAR SCREENING 2000; 4:363-372. [PMID: 10838433 DOI: 10.1177/108705719900400611] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Although parathyroid hormone (PTH) has the ability to stimulate bone growth in both rats and humans, its mechanism of action is not fully understood at the molecular level. An in vitro marker that reflects the in vivo anabolic actions of PTH would facilitate the discovery of small-molecule compounds that stimulate bone growth. We therefore compared the patterns of gene expression in three cell lines treated with PTH. The levels of c-fos, collagenase, interleukin-6 (IL-6), and collagen mRNA were determined by reverse transcription-polymerase chain reaction (RT-PCR) in three osteoblast-like cell lines. The most responsive marker was c-fos, which was induced 5-10-fold after 1 h of PTH treatment in the UMR106-01 cell line. Because it is a critical early response gene in bone growth, we investigated the possibility of using c-fos stimulation as a method to screen for compounds that can stimulate bone formation. A highly sensitive, medium-throughput RT-PCR assay for c-fos mRNA expression was established using the Taqmantrade mark Detection System (Perkin Elmer, Mississauga, Ontario). Cells were treated with a series of compounds to determine the specificity of c-fos stimulation. Of the compounds tested, only PTH, prostaglandin E(2), 8-bromo-cAMP, and forskolin induced c-fos mRNA levels, indicating that this assay was specific for compounds that are known to induce cAMP and stimulate bone growth. These results indicate that a simple in vitro assay for c-fos may be a reliable method for the screening of compounds that stimulate bone growth in vivo.
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Hwang K, Lee DK, Lee SI. Nodular fasciitis presenting as a parotid tumour after face lifting. BRITISH JOURNAL OF PLASTIC SURGERY 2000; 53:345-7. [PMID: 10876263 DOI: 10.1054/bjps.1999.3286] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Nodular fasciitis, a benign, pseudosarcomatous proliferative lesion of the soft tissue, is frequently misinterpreted as a sarcoma, both clinically and microscopically. Lesions associated with the parotid gland have been very rarely reported. We report a case of nodular fasciitis mimicking a parotid tumour after a facelift. We performed histological and immunohistochemical study and CT scan for it is difficult to make a differential diagnosis. We confirmed the final diagnosis as intraparotid nodular fasciitis. Superficial parotidectomy was performed because of initial pathological misdiagnosis reported as a dermatofibroma. The subsequent diagnosis was confirmed to be nodular fasciitis on the basis of immunohistochemical study. There was no recurrence after follow-up to 18 months. Proper diagnosis of nodular fasciitis in the parotid region and early recognition of its benign nature are necessary to differentiate it from other various benign and malignant tumours of the parotid gland.
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Meng CQ, Rakhit S, Lee DK, Kamboj R, McCallum KL, Mazzocco L, Dyne K, Slassi A. 5-Thienyltryptamine derivatives as serotonin 5-HT1B/1D receptor agonists: potential treatments for migraine. Bioorg Med Chem Lett 2000; 10:903-5. [PMID: 10853656 DOI: 10.1016/s0960-894x(00)00133-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
A series of 5-(2- or 3-thienyl)tryptamine derivatives (9) has been synthesized and shown to be potent and selective 5-HT1D versus 5-HT1B receptor agonists and, therefore, potential treatments for migraine.
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Kim HS, Lee DK, Jeong YS, Kim KH, Baik SK, Kwon SO, Cho MY. Successful endoscopic management of a perforated gastric dysplastic lesion after endoscopic mucosal resection. Gastrointest Endosc 2000; 51:613-5. [PMID: 10805857 DOI: 10.1016/s0016-5107(00)70305-1] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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138
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Isaac M, Slassi A, O'Brien A, Edwards L, MacLean N, Bueschkens D, Lee DK, McCallum K, De Lannoy I, Demchyshyn L, Kamboj R. Pyrrolo[3,2,1-ij]quinoline derivatives, a 5-HT2c receptor agonist with selectivity over the 5-HT2a receptor: potential therapeutic applications for epilepsy and obesity. Bioorg Med Chem Lett 2000; 10:919-21. [PMID: 10853660 DOI: 10.1016/s0960-894x(00)00141-4] [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: 10/18/2022]
Abstract
A series of pyrrolo[3,2,1-ij]quinoline derivatives was synthesized, evaluated for their activity against the 5-HT2c and 5-HT2a, receptors and found to be agonists at 5-HT2c with selectivity over 5-HT2a.
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Park S, Lee DK, Whang YH, Yang CH. Momordin I, a compound of ampelopsis radix, inhibits AP-1 activation induced by phorbol ester. Cancer Lett 2000; 152:1-8. [PMID: 10754199 DOI: 10.1016/s0304-3835(99)00413-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Recently, we reported that momordin I from Ampelopsis radix is an activator protein-1 (AP-1) function inhibitor. Mormordin I showed both inhibition of AP-1 transcriptional activity and cellular cytotoxicity. Moreover, its inhibitory action was also identified in the animal experiments. The present study attempted to determine the mechanism of the action of momordin I more clearly. In mouse fibroblast cells, momordin I suppressed the AP-1 activity induced by phorbol 12-myristate 13-acetate (PMA), as well as blocked the de novo synthesis of AP-1 protein. Momordin I also showed cell cytotoxic activities on various cell lines and blocked the uptake of [(3)H]thymidine in cell proliferation induced by PMA. From these results, the inhibitory action of momordin I on AP-1 was clearly identified. Through the competitive binding assays, it appears that the inhibitory site of momordin I might be in the Jun/Fos dimer, and not in the DNA. Momordin I also showed the inhibitory action on the Jun/Jun homodimer, as well as on the Jun/Fos heterodimer. It also inhibited the autoregulated de novo synthesis of AP-1 by the Jun/Jun homodimer. In addition, since the truncated AP-1 used in this study only has the bZip regions of c-Jun and c-Fos, it appears that the inhibitory action site of momordin I may be the basic region of c-Jun instead of on the same region of c-Fos.
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Lee DK, Duan HO, Chang C. From androgen receptor to the general transcription factor TFIIH. Identification of cdk activating kinase (CAK) as an androgen receptor NH(2)-terminal associated coactivator. J Biol Chem 2000; 275:9308-13. [PMID: 10734072 DOI: 10.1074/jbc.275.13.9308] [Citation(s) in RCA: 87] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The androgen receptor (AR), like other steroid receptors, modulates the activity of the general transcription machinery on the core promoter to exert its function as a regulator. Co-immunoprecipitation of prostate cancer LNCaP cell extract using protein A-Sepharose coupled with anti-AR antibody indicates that the AR interacts with the general transcription factor TFIIH in a physiological condition. Co-transfection of cdk activating kinase (CAK), the kinase moiety of TFIIH, enhanced AR-mediated transcription in a ligand-dependent manner in human prostate cancer PC-3 and LNCaP cells, and in a ligand-independent manner in human prostate cancer DU145 cells. Detailed interaction studies further revealed that the AR NH(2)-terminal domain interacting with CAK was essential for the CAK-induced AR transactivation. Together, our data suggest that the AR may interact with TFIIH for efficient communication with the general transcription factors/RNA polymerase II on the core promoter.
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141
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Glennon RA, Lee M, Rangisetty JB, Dukat M, Roth BL, Savage JE, McBride A, Rauser L, Hufeisen S, Lee DK. 2-Substituted tryptamines: agents with selectivity for 5-HT(6) serotonin receptors. J Med Chem 2000; 43:1011-8. [PMID: 10715164 DOI: 10.1021/jm990550b] [Citation(s) in RCA: 130] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Several 2-alkyl-5-methoxytryptamine analogues were designed and prepared as potential 5-HT(6) serotonin agonists. It was found that 5-HT(6) receptors accommodate small alkyl substituents at the indole 2-position and that the resulting compounds can bind with affinities comparable to that of serotonin. In particular, 2-ethyl-5-methoxy-N, N-dimethyltryptamine (8) binds with high affinity at human 5-HT(6) receptors (K(i) = 16 nM) relative to 5-HT (K(i) = 75 nM) and was a full agonist, at least as potent (8: K(act) = 3.6 nM) as serotonin (K(act) = 5.0 nM), in activating adenylate cyclase. Compound 8 displays modest affinity for several other populations of 5-HT receptors, notably h5-HT(1A) (K(i) = 170 nM), h5-HT(1D) (K(i) = 290 nM), and h5-HT(7) (K(i) = 300 nM) receptors, but is otherwise quite selective. Compound 8 represents the first and most selective 5-HT(6) agonist reported to date. Replacing the 2-ethyl substituent with a phenyl group results in a compound that retains 5-HT(6) receptor affinity (i.e., 10: K(i) = 20 nM) but lacks agonist character. 2-Substituted tryptamines, then, might allow entry to a novel class of 5-HT(6) agonists and antagonists.
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Kim TJ, Kim SH, Sim JS, Seong CK, Lee DK. Ultrasonographic findings of an intratesticular adenomatoid tumor. JOURNAL OF ULTRASOUND IN MEDICINE : OFFICIAL JOURNAL OF THE AMERICAN INSTITUTE OF ULTRASOUND IN MEDICINE 2000; 19:227-229. [PMID: 10709841 DOI: 10.7863/jum.2000.19.3.227] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Lee DK, Lynch KR, Nguyen T, Im DS, Cheng R, Saldivia VR, Liu Y, Liu IS, Heng HH, Seeman P, George SR, O'Dowd BF, Marchese A. Cloning and characterization of additional members of the G protein-coupled receptor family. BIOCHIMICA ET BIOPHYSICA ACTA 2000; 1490:311-23. [PMID: 10684976 DOI: 10.1016/s0167-4781(99)00241-9] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
A search of the expressed sequence tag (EST) database retrieved a human cDNA sequence which partially encoded a novel G protein-coupled receptor (GPCR) GPR26. A human genomic DNA fragment encoding a partial open reading frame (ORF) and a rat cDNA encoding the full length ORF of GPR26 were obtained by library screening. The rat GPR26 cDNA encoded a protein of 317 amino acids, most similar (albeit distantly related) to the serotonin 5-HT(5A) and gastrin releasing hormone BB2 receptors. GPR26 mRNA expression analysis revealed signals in the striatum, pons, cerebellum and cortex. HEK293 and Rh7777 cells transfected with GPR26 cDNA displayed high basal cAMP levels, slow growth rate of clonal populations and derangements of normal cell shape. We also used a sequence reported only in the patent literature encoding GPR57 (a.k.a. HNHCI32) to PCR amplify a DNA fragment which was used to screen a human genomic library. This resulted in the cloning of a genomic fragment containing a pseudogene, psiGPR57, with a 99.6% nucleotide identity to GPR57. Based on shared sequence identities, the receptor encoded by GPR57 was predicted to belong to a novel subfamily of GPCRs together with GPR58 (a.k.a. phBL5, reported only in the patent literature), putative neurotransmitter receptor (PNR) and a 5-HT(4) pseudogene. Analysis of this subfamily revealed greatest identities (approximately 56%) between the receptors encoded by GPR57 and GPR58, each with shared identities of approximately 40% with PNR. Furthermore, psiGPR57, GPR58, PNR and the 5-HT(4) pseudogene were mapped in a cluster localized to chromosome 6q22-24. PNR and GPR58 were expressed in COS cells, however no specific binding was observed for various serotonin receptor-specific ligands.
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Shin EC, Cho SE, Lee DK, Hur MW, Paik SR, Park JH, Kim J. Expression patterns of alpha-synuclein in human hematopoietic cells and in Drosophila at different developmental stages. Mol Cells 2000; 10:65-70. [PMID: 10774749 DOI: 10.1007/s10059-000-0065-x] [Citation(s) in RCA: 69] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
Alpha-synuclein, a presynaptic protein of the central nervous system, has been implicated in the synaptic events such as neuronal plasticity during development and learning, and neuronal degeneration under pathological conditions. As an effort to understand the biological function of alpha-synuclein, we examined the expression patterns of alpha-synuclein in various human hematopoietic cells, and in Drosophila at different developmental stages. The alpha-synuclein was ubiquitously expressed in all the tested hematopoietic cells including T cells, B cells, NK cells, and monocytes, as well as in the lymphoma cell lines, Jurkat and K562. A potential alpha-synuclein homologue was also expressed in Drosophila, and its expression appeared to be temporally and spatially regulated during development. Our data suggest that alpha-synuclein may function in invertebrates as well as in vertebrates and its function may not be restricted to the neuron.
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Lee DK, Im JG, Lee KS, Lee JS, Seo JB, Goo JM, Kim TS, Lee JW. B-cell lymphoma of bronchus-associated lymphoid tissue (BALT): CT features in 10 patients. J Comput Assist Tomogr 2000; 24:30-4. [PMID: 10667654 DOI: 10.1097/00004728-200001000-00006] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE The purpose of this work was to describe the CT findings of pathologically confirmed bronchus-associated lymphoid tissue (BALT) lymphoma in 10 patients. METHOD The CT examinations of 10 patients with pathologically proven BALT lymphoma were reviewed retrospectively by two radiologists. Evaluated findings included number and distribution of lesions. We also assessed other CT findings such as presence of airspace consolidation, nodules, ground-glass attenuation, bubble-like radiolucencies, air bronchogram, bronchial dilatation, and lymphadenopathy. RESULTS Pulmonary lesions were revealed as airspace consolidation in six patients (60%) and nodule(s) in six (60%). Multiplicity of disease was seen in seven patients (70%) and bilateral lung lesions in six (60%). Areas of ground-glass attenuation were seen in seven patients (70%). Bubble-like radiolucencies were present in five patients (50%) and air bronchogram in nine (90%). Findings of bronchial dilatation and lymphadenopathy were seen in three patients (30%). CONCLUSION BALT lymphomas usually appear as airspace consolidation or nodules with air bronchogram or adjacent ground-glass attenuation at CT. These findings are similar to previous descriptions of pseudolymphomas. Multiple bilateral lesions are common in BALT lymphoma. Bubble-like radiolucencies have not been described previously and can be an additional finding of BALT lymphoma.
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O'Dowd BF, Lee DK, Huang W, Nguyen T, Cheng R, Liu Y, Wang B, Gershengorn MC, George SR. TRH-R2 exhibits similar binding and acute signaling but distinct regulation and anatomic distribution compared with TRH-R1. Mol Endocrinol 2000; 14:183-93. [PMID: 10628757 DOI: 10.1210/mend.14.1.0407] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
TRH (thyroliberin) is a tripeptide (pGlu-His-ProNH2) that signals via G protein-coupled receptors. Until recently, only a single receptor for TRH was known (TRH-R1), but two groups identified a second receptor, TRH-R2. We independently discovered TRH-R2. Using an extensive set of TRH analogs, we found no differences in TRH-R1 and TRH-R2 binding or in acute stimulation of signaling. TRH-R2 was more rapidly internalized upon binding TRH and exhibited a greater level of TRH-induced down-regulation than TRH-R1. During prolonged exposure to TRH, cells expressing TRH-R2 exhibited a lower level of gene induction than cells expressing TRH-R1. TRH-R2 receptor mRNA was present in very discrete nuclei and regions of rat brain. A major mRNA transcript for TRH-R2 was seen in the cerebral cortex, pons, thalamus, hypothalamus, and midbrain with faint bands found in the striatum and pituitary. The extensive distribution of TRH-R2 in the brain suggests that it mediates many of the known functions of TRH that are not transduced by TRH-R1. The variations in agonist-induced internalization and down-regulation/desensitization, and anatomic distribution of TRH-R2 compared with TRH-R1, suggest important functional differences between the two receptors.
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Lee DK, Cheng R, Nguyen T, Fan T, Kariyawasam AP, Liu Y, Osmond DH, George SR, O'Dowd BF. Characterization of apelin, the ligand for the APJ receptor. J Neurochem 2000; 74:34-41. [PMID: 10617103 DOI: 10.1046/j.1471-4159.2000.0740034.x] [Citation(s) in RCA: 480] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
The apelin peptide was recently discovered and demonstrated to be the endogenous ligand for the G protein-coupled receptor, APJ. A search of the GenBank databases retrieved a rat expressed sequence tag partially encoding the preproapelin sequence. The GenBank search also revealed a human sequence on chromosome Xq25-26.1, containing the gene encoding preproapelin. We have used the rat sequence to screen a rat brain cDNA library to obtain a cDNA encoding the full-length open reading frame of rat preproapelin. This cDNA encoded a protein of 77 amino acids, sharing an identity of 82% with human preproapelin. Northern and in situ hybridization analyses revealed both human and rat apelin and APJ to be expressed in the brain and periphery. Both sequence and mRNA expression distribution analyses revealed similarities between apelin and angiotensin II, suggesting they that share related physiological roles. A synthetic apelin peptide was injected intravenously into male Wistar rats, resulting in immediate lowering of both systolic and diastolic blood pressure, which persisted for several minutes. Intraperitoneal apelin injections induced an increase in drinking behavior within the first 30 min after injection, with a return to baseline within 1 h.
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148
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Hwang K, Lee DK, Lee SI. Tenosynovial giant cell tumor of finger, localized type: a case report. J Korean Med Sci 1999; 14:682-4. [PMID: 10642950 PMCID: PMC3054441 DOI: 10.3346/jkms.1999.14.6.682] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The authors report a typical case of tenosynovial giant cell tumor of the right middle finger of a 31-year-old man. Histologically, this tumor is characterized by a discrete proliferation of rounded synovial-like cells accompanied by a variable number of multinucleated giant cells, inflammatory cells, and xanthoma cells. Clinicopathologically, this tumor is a benign lesion that nonetheless possesses a capacity for local recurrence. Local excision with a small cuff of normal tissue is the treatment of choice in this tumor.
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Abstract
OBJECTIVE Numerous investigators have proposed a role for bacteria in biliary lithogenesis. We hypothesized that bacterial DNA is present in gallstones, and that categorical differences exist between gallstone type and the frequency of bacterial sequences. METHODS Polymerase chain reaction (PCR) was used to amplify bacterial 16S rRNA and uidA (encoding Escherichia coli [E. coli] beta-glucuronidase) genes in different types of gallstones. PCR products were sequenced. RESULTS Bacterial 16S rRNA and uidA DNA sequences in E. coli were detected in all brown pigment, common bile duct, and mixed cholesterol gallstones (n = 14). In contrast, only one (14%) of seven pure cholesterol gallstones yielded a PCR product. Most (88%) mixed cholesterol gallstones yielded PCR amplification products from their central, as well as their outer, portions. Sequenced products possessed 88-98% identity to 16S rRNA genes of E. coli and Pseudomonas species. CONCLUSIONS Bacterial DNA sequences are usually present in mixed cholesterol (to 95% cholesterol content), brown pigment, and common bile duct, but rarely in pure cholesterol gallstones. The presence of bacterial beta-glucuronidase is also suggested. The role of bacteria and their products in the formation of mixed cholesterol gallstones, which comprise the majority of cholesterol gallstones, warrants further study.
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Lee DK, Kim S, Lis JT. Different upstream transcriptional activators have distinct coactivator requirements. Genes Dev 1999; 13:2934-9. [PMID: 10580000 PMCID: PMC317159 DOI: 10.1101/gad.13.22.2934] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Activated transcription by RNA polymerase II (Pol II) requires coactivators, one of which is the SRB/mediator. Whereas Srb4, an essential subunit of the SRB/mediator, is broadly required for Pol II transcription in yeast, we have shown that it is dispensable for the transcriptional activation of some genes. Here, we show that transcriptional activation by different natural activators, and by artificial recruitment of various transcription factors, have very different degrees of Srb4 independence. These data, and the analysis of an rgr1 mutant, point to an Rgr1 subcomplex of the SRB/mediator as the mechanistic route of activation by Srb4-independent activators in vivo.
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