76
|
Lee EJ, Choi KH, Kang SW, Lee IW. Intraventricular hemorrhage caused by lateral ventricular meningioma: a case report. Korean J Radiol 2001; 2:105-7. [PMID: 11752978 PMCID: PMC2718099 DOI: 10.3348/kjr.2001.2.2.105] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Meningiomas causing intracranial hemorrhage are rare, and hemorrhage from a lateral ventricular meningioma seems to be even rarer. We report a case of trigonal meningioma in a 43-year-old woman who presented with intraventricular hemorrhage, and describe the CT, MRI and angiographic findings.
Collapse
|
77
|
Hwang SS, Kim HH, Park SH, Kim SE, Jung JI, Ahn BY, Kim SH, Chung SK, Park YH, Choi KH. N-butyl-2-cyanoacrylate pulmonary embolism after endoscopic injection sclerotherapy for gastric variceal bleeding. J Comput Assist Tomogr 2001; 25:16-22. [PMID: 11176287 DOI: 10.1097/00004728-200101000-00003] [Citation(s) in RCA: 91] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
PURPOSE The purpose of this work was to describe the radiologic and clinical manifestations of n-butyl-2-cyanoacrylate pulmonary embolism (PE) after endoscopic injection sclerotherapy (EIS) for gastric variceal bleeding. METHOD From 1992 to 1999, the medical records of 140 patients who had undergone EIS using n-butyl-2-cyanoacrylate were reviewed for identification of respiratory symptoms and amount of injection, and their pre- and postprocedure chest radiographs were reviewed to identify PE. In patients with PE, pre- and postprocedure chest radiographs (6/6), chest CT scans (3/6), lung perfusion scans (3/6), and follow-up chest radiographs (6/6) were analyzed retrospectively. RESULTS Radiographically evident PE was observed in 6 (4.3%) of 140 patients. In comparison with patients without emboli, these patients received a higher mean volume of injection (4.2 vs. 1.8 ml) (p = 0.0011). Four of the six patients with pulmonary emboli had respiratory symptoms. Chest radiographs and CT scans showed unusual tubular or nodular, radiopaque pulmonary emboli along the pulmonary vessels. Multiple peripheral, wedge-shaped, subsegmental perfusion defects were seen on perfusion lung scans. In five of six patients, the radiographic abnormalities showed complete or partial resolution. There were no fatalities directly associated with PE. CONCLUSION Radiographically evident PEs are uncommonly observed following EIS and appear to be more common in patients receiving a higher volume of liquid acrylate. Affected patients were either mildly symptomatic or asymptomatic, and there were no direct fatalities of this complication.
Collapse
|
78
|
Choi KH, Wynne ME. Providing services to Asian Americans with developmental disabilities and their families: mainstream service providers' perspective. Community Ment Health J 2000; 36:589-95. [PMID: 11079186 DOI: 10.1023/a:1001934202450] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
This survey investigated the opinions and perceptions of 44 mainstream social service providers regarding barriers to Asian Americans with developmental disabilities and their families receiving appropriate supportive services. Six main barriers were identified: (1) Language and communication difficulties; (2) Lack of knowledge concerning mainstream service delivery system; (3) Perceived cultural differences; (4) Being a "minority within a minority" in the service delivery system; (5) Individual differences within families and differences among Asian ethnic groups; and (6) Lack of resources to meet needs within the family. Implications of the interrelationships among the identified barriers were discussed.
Collapse
|
79
|
Abstract
Nephrotoxicity is a major limiting factor in the use of aminoglycoside antibiotics, the mechanisms for which are still speculative. To clarify the mechanisms of renal tubular cell death induced by aminoglycosides, we examined the renal proximal tubule-like cell line, LLC-PK1, after inducing apoptosis through a chronic treatment with gentamicin (GM). Changes in the expression of the Fas were also investigated. On flow cytometric analysis, 5.7 +/- 3.3% of the control cells appeared in a region of decreased forward light scatter and increased side light scatter, where both indices represent the characteristics of apoptotic cell death. Compared to the control, treatment with 10 mM of GM for 15 days significantly increased the proportion of cells in the apoptotic region to 23.9 +/- 8.5%. This finding was supported by electrophoretic analysis of the DNA extracted from the GM-treated cells, where a series of bands corresponding to integer multiples of 180 to 200 base pairs was visualized. However, the 15-day GM treatment did not cause a significant elevation in the expression of the 45 kD Fas protein, the cell surface molecule that stimulates apoptosis, by Western blot analysis. In conclusion, long-term exposure to GM induces apoptosis of the renal tubular epithelial cells, and this process may contribute to some of the aminoglycoside nephrotoxicities. Further studies are needed on the mechanism(s) of apoptosis induced by GM.
Collapse
|
80
|
Kim SH, Ahn KJ, Lee JM, Choi KH, Han SH. The usefulness of orbital lines in detecting blow-out fracture on plain radiography. Br J Radiol 2000; 73:1265-9. [PMID: 11205669 DOI: 10.1259/bjr.73.876.11205669] [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: 11/05/2022] Open
Abstract
The purpose of this study was to assess the diagnostic value of orbital line changes on plain radiographs in detecting blow-out fracture. 92 cases of surgically confirmed blow-out fracture were retrospectively analysed in regard to plain radiographs and CT. Anterior and posterior lamina papyracea lines (ALPL and PLPL, respectively) of the orbital medial wall as well as the posteromedial floor line (PMFL) were assessed on orbital posteroanterior projections. The inferomedial orbital line (IMOL) and the inferior wall line were assessed on Waters projections. Orbital lines on plain radiographs were compared with CT findings. Of 53 cases of lamina papyracea fracture, 47 cases showed orbital line changes on plain radiographs (sensitivity 88.7%). Changes of PLPL (41/47), IMOL (29/47), ALPL (4/47) and PMFL (2/47) were demonstrated as depression, loss, discontinuity and irregularity. In four cases showing normal radiographs, the fractures measured less than 9 mm in size on CT. All 25 cases with orbital floor fracture accompanying medial wall fracture demonstrated orbital line changes of PMFL (16/25), PLPL (14/25), ALPL (3/25) and IMOL (2/25) (sensitivity 100%). 12 of 14 cases with orbital floor fracture demonstrated changes of inferior wall line (7/12) and PMFL (6/12) (sensitivity 85.7%). Two cases demonstrated asymmetric focal soft tissue density without orbital line changes. Orbital line changes on plain radiographs corresponded well with CT findings, confirming the usefulness of plain radiographs in detecting blow-out fracture.
Collapse
|
81
|
Lee JH, Park YS, Kim KM, Kim KJ, Ahn CH, Lee SY, Choi KH. Pituitary aspergillosis mimicking pituitary tumor. AJR Am J Roentgenol 2000; 175:1570-2. [PMID: 11090377 DOI: 10.2214/ajr.175.6.1751570] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
|
82
|
Kim SI, Yoo TH, Song HY, Hwang JH, Lee HY, Han DS, Moon JI, Kim YS, Park KI, Paeng KJ, Choi KH. Hyperhomocysteinemia in renal transplant recipients with cyclosporine. Transplant Proc 2000; 32:1878-9. [PMID: 11119981 DOI: 10.1016/s0041-1345(00)01473-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
|
83
|
Kim SI, Song HY, Hwang JH, Chong DL, Lee HY, Han DS, Moon JI, Kim YS, Park KI, Kim KS, Choi KH. Cyclosporine nephrotoxicity: the mechanisms of cell injury by cyclosporine A in renal proximal tubular cells. Transplant Proc 2000; 32:1621-2. [PMID: 11119864 DOI: 10.1016/s0041-1345(00)01446-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
84
|
Choi KH, Kim SI, Shin SK, Moon JI, Kim YS, Lee HY, Han DS, Park K. Renal replacement therapies in the elderly: renal transplantation and continuous ambulatory peritoneal dialysis. Transplant Proc 2000; 32:1814. [PMID: 11119949 DOI: 10.1016/s0041-1345(00)01361-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
|
85
|
Kim WH, Kang KH, Kim MY, Choi KH. Induction of p53-independent p21 during ceramide-induced G1 arrest in human hepatocarcinoma cells. Biochem Cell Biol 2000; 78:127-35. [PMID: 10874474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023] Open
Abstract
Ceramide is known to induce pRb (retinoblastoma gene product) dephosphorylation through the activation of ceramide-activated protein phosphatase (CAPP) during G1 arrest, but other molecular mechanisms linked to regulation of pRb dephosphorylation during ceramide-induced G1 arrest are poorly understood. In this paper, we investigated whether p21, a cdk (cyclin-dependent kinase) inhibitor, is involved in the induction of pRb dephosphorylation during ceramide-induced G1 arrest. In SK-Hep-1 cells, the addition of ceramide resulted in pRb dephosphorylation and G1 arrest. The activity of cdk2 was inhibited in response to ceramide during this process. p21 protein and mRNA were remarkably induced, while the protein level of p53, known as a transcriptional activator of p21, was not elevated at the same condition. p21 induction was also observed in the Hep3B cells lacking a functional p53 after exposure to ceramide. Although p21 is induced in ceramide-treated Hep3B cells, Hep3B cells do not induce G1 arrest, because Hep3B cells are deficient in a functional pRb protein. To confirm that pRb is a critical target for the induction of G1 arrest by inhibiting cdk2 activity through p53-independent p21, pRb-expressing vector was transfected into Hep3B cells. After treatment with ceramide, pRb-expressing cells (pRb+/+), but not pRb-/- cells, were arrested in G1 phase. In pRb+/+ cells, ceramide-mediated G1 arrest was accompanied by the accumulation of hypophosphorylated pRb and p21 associated with cdk2. Together, these results suggest that p21, induced through p53-independent pathway, participates in the induction of pRb dephosphorylation by inhibiting cdk2 activity during ceramide-mediated G1 arrest in hepatocarcinoma cells.
Collapse
|
86
|
Kim YS, Ryu JH, Han SJ, Choi KH, Nam KB, Jang IH, Lemaitre B, Brey PT, Lee WJ. Gram-negative bacteria-binding protein, a pattern recognition receptor for lipopolysaccharide and beta-1,3-glucan that mediates the signaling for the induction of innate immune genes in Drosophila melanogaster cells. J Biol Chem 2000; 275:32721-7. [PMID: 10827089 DOI: 10.1074/jbc.m003934200] [Citation(s) in RCA: 218] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Pattern recognition receptors, non-clonal immune proteins recognizing common microbial components, are critical for non-self recognition and the subsequent induction of Rel/NF-kappaB-controlled innate immune genes. However, the molecular identities of such receptors are still obscure. Here, we present data showing that Drosophila possesses at least three cDNAs encoding members of the Gram-negative bacteria-binding protein (DGNBP) family, one of which, DGNBP-1, has been characterized. Western blot, flow cytometric, and confocal laser microscopic analyses demonstrate that DGNBP-1 exists in both a soluble and a glycosylphosphatidylinositol-anchored membrane form in culture medium supernatant and on Drosophila immunocompetent cells, respectively. DGNBP-1 has a high affinity to microbial immune elicitors such as lipopolysaccharide (LPS) and beta-1,3-glucan whereas no binding affinity is detected with peptidoglycan, beta-1,4-glucan, or chitin. Importantly, the overexpression of DGNBP-1 in Drosophila immunocompetent cells enhances LPS- and beta-1,3-glucan-induced innate immune gene (NF-kappaB-dependent antimicrobial peptide gene) expression, which can be specifically blocked by pretreatment with anti-DGNBP-1 antibody. These results suggest that DGNBP-1 functions as a pattern recognition receptor for LPS from Gram-negative bacteria and beta-1, 3-glucan from fungi and plays an important role in non-self recognition and the subsequent immune signal transmission for the induction of antimicrobial peptide genes in the Drosophila innate immune system.
Collapse
|
87
|
Choi KH, Kremer L, Besra GS, Rock CO. Identification and substrate specificity of beta -ketoacyl (acyl carrier protein) synthase III (mtFabH) from Mycobacterium tuberculosis. J Biol Chem 2000; 275:28201-7. [PMID: 10840036 DOI: 10.1074/jbc.m003241200] [Citation(s) in RCA: 142] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The long-chain alpha-alkyl-beta-hydroxy fatty acids, termed mycolic acids, which are characteristic components of the mycobacterial cell wall are produced by successive rounds of elongation catalyzed by a multifunctional (type I) fatty acid synthase complex followed by a dissociated (type II) fatty acid synthase. In bacterial type II systems, the first initiation step in elongation is the condensation of acetyl-CoA with malonyl-acyl carrier protein (ACP) catalyzed by beta-ketoacyl-ACP III (FabH). An open reading frame in the Mycobacterium tuberculosis genome (Rv0533c), now termed mtfabH, was 37.3% identical to Escherichia coli ecFabH and contained the Cys-His-Asn catalytic triad signature. However, the purified recombinant mtFabH clearly preferred long-chain acyl-CoA substrates rather than acyl-ACP primers and did not utilize acetyl-CoA as a primer in comparison to ecFabH. In addition, purified mtFabH was sensitive to thiolactomycin and resistant to cerulenin in an in vitro assay. However, mtFabH overexpression in Mycobacterium bovis BCG did not confer thiolactomycin resistance, suggesting that mtFabH may not be the primary target of thiolactomycin inhibition in vivo and led to several changes in the lipid composition of the bacilli. The data presented is consistent with a role for mtFabH as the pivotal link between the type I and type II fatty acid elongation systems in M. tuberculosis. This study opens up new avenues for the development of selective and novel anti-mycobacterial agents targeted against mtFabH.
Collapse
|
88
|
Choi KH, Hama-Inaba H, Wang B, Haginoya K, Odaka T, Yamada T, Hayata I, Ohyama H. UVC-induced apoptosis in human epithelial tumor A431 cells: sequence of apoptotic changes and involvement of caspase (-8 and -3) cascade. JOURNAL OF RADIATION RESEARCH 2000; 41:243-258. [PMID: 11210827 DOI: 10.1269/jrr.41.243] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Human epidermoid tumor A431 cells underwent apoptosis following exposure to ultraviolet C (UVC). The apoptosis was of the interphase death type, and mostly occurred within one cell cycle, independent of the cell-cycle phases. We further examined the detailed sequential order of apoptotic changes in cells after UVC exposure and the involvement of caspases using six caspase inhibitors. The loss of mitochondrial transmembrane potential (delta psi m) appeared in the earliest phase; subsequently, the chromatin condensation and DNA-fragmentation occurred. Cell shrinkage and loss of the plasma-membrane integrity, judged by propidium iodide (PI) staining, were observed in the later phase. A broad-spectrum caspase inhibitor, z-VAD-fmk, completely prevented all apoptotic changes, except for the depletion of delta psi m. Both Ac-DEVD-CHO and Ac-IETD-CHO, inhibitors of caspase -3 and -8, respectively, effectively inhibited typical chromatin condensation to almost the same extent. However, the nuclei still showed partial condensation. A caspase -9 inhibitor, Ac-LEHD-CHO, did not prevent chromatin condensation, though it partially inhibited cell-size reduction and PI-stainability. None of the caspase inhibitors could inhibit the delta psi m reduction. These results strongly suggest that the collapse of delta psi m is not a part of the central apoptotic machinery, and that caspase cascade(s), especially caspase-8 to -3, play an important role in UVC-induced apoptosis in A431.
Collapse
|
89
|
Lee HJ, Ahn IA, Ro S, Choi KH, Choi YS, Lee KB. Role of azaamino acid residue in beta-turn formation and stability in designed peptide. THE JOURNAL OF PEPTIDE RESEARCH : OFFICIAL JOURNAL OF THE AMERICAN PEPTIDE SOCIETY 2000; 56:35-46. [PMID: 10917455 DOI: 10.1034/j.1399-3011.2000.00717.x] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The structural perturbation induced by C(alpha)-->N(alpha) exchange in azaamino acid-containing peptides was predicted by ab initio calculation of the 6-31G* and 3-21G* levels. The global energy-minimum conformations for model compounds, For-azaXaa-NH2 (Xaa=Gly, Ala, Leu) appeared to be the beta-turn motif with a dihedral angle of phi= +/- 90 degrees, psi=0 degrees. This suggests that incorporation of the azaXaa residue into the i+2 position of designed peptides could stabilize the beta-turn structure. The model azaLeu-containing peptide, Boc-Phe-azaLeu-Ala-OMe, which is predicted to adopt a beta-turn conformation was designed and synthesized in order to experimentally elucidate the role of the azaamino acid residue. Its structural preference in organic solvents was investigated using 1H NMR, molecular modelling and IR spectroscopy. The temperature coefficients of amide protons, the characteristic NOE patterns, the restrained molecular dynamics simulation and IR spectroscopy defined the dihedral angles [ (phi i+1, psi i+1) (phi i+2, psi i+2)] of the Phe-azaLeu fragment in the model peptide, Boc-Phe-azaLeu-Ala-OMe, as [(-59 degrees, 127 degrees) (107 degrees, -4 degrees)]. This solution conformation supports a betaII-turn structural preference in azaLeu-containing peptides as predicted by the quantum chemical calculation. Therefore, intercalation of the azaamino acid residue into the i+2 position in synthetic peptides is expected to provide a stable beta-turn formation, and this could be utilized in the design of new peptidomimetics adopting a beta-turn scaffold.
Collapse
|
90
|
Choi KH, Roberts KJ, Gomez C, Grinstead O. Facilitators and barriers to use of the female condom: qualitative interviews with women of diverse ethnicity. Women Health 2000; 30:53-70. [PMID: 10813267 DOI: 10.1300/j013v30n01_04] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Women in the United States, particularly African-Americans and Hispanics, are at increased risk for HIV. The female condom now offers women a potentially important option for HIV prevention, yet few efforts have been made to increase its use. To elucidate strategies to promote the use of the female condom, we conducted in-depth interviews with 62 women recruited from the four major racial/ethnic groups of the U.S. (African-American, Asian-American, Hispanic, and white). Subject recruitment took place at a family planning clinic in San Francisco during 1996-97. We identified four major types of facilitators and barriers to use of the female condom: mechanical, psychosexual, interpersonal, and situational. Specifically, the mechanical facilitators and barriers included positive and negative aspects of the device, and difficulty with insertion. The psychosexual factors were female empowerment, more options for contraception and disease prevention, discomfort with vaginal insertion, and condom use norms. The interpersonal factors included: enhanced communication, relationship status, partner preferences, and partner objections. Finally, the situations that made women disinclined to use the device were: no access to the female condom when having sex and using other forms of contraceptives. The implications of these findings for HIV prevention and future research are discussed.
Collapse
|
91
|
Choi KH, Kim KH, Kim HJ. Evaluation of tTA-mediated gene activation system on human cytomegalovirus and herpes simplex virus type-1 infections. Arch Pharm Res 2000; 23:257-60. [PMID: 10896059 DOI: 10.1007/bf02976456] [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: 10/21/2022]
Abstract
The tetracycline-controlled transactivator (tTA)-mediated gene activation system was examined in virus infected cells to determine its role in the control of gene expression. In the presence of tTA, the gene expression from the tetO-modified minimal promoter was efficiently activated in the uninfected cells, whereas essentially no activation was observed from the only minimal promoter without the seven direct repeats of 42 bp tetO sequences. However, essentially no activation was observed when only the minimal promoter was used, without the seven direct repetitions of the 42 bp tetO sequences. On the other hand, in the infected cells, a substantial background of beta-glucuronidase expression was detected in the absence of tTA, even though tTA stimulated the gene expression by approximately 7-fold. This background expression indicates that the sequences within or nearby tetO are involved in the background stimulation of the gene expression by HCMV and HSV-1. These results suggest that the application of the tTA-mediated gene activation system may not be extremely useful for studying the biological roles of HCMV and HSV genes in the viral replicative cycles, because of the basal activity of the gene expression.
Collapse
|
92
|
Noh H, Song HY, Kang SW, Choi KH, Lee HY, Han DS. Impact of total solute clearance on clinical outcomes in Korean CAPD patients. Perit Dial Int 2000; 20:345-8. [PMID: 10898056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023] Open
|
93
|
Choi KH, Zarandi B, Todd KG, Biondo AM, Greenshaw AJ. Effects of AMPA/kainate receptor blockade on responses to dopamine receptor agonists in the core and shell of the rat nucleus accumbens. Psychopharmacology (Berl) 2000; 150:102-11. [PMID: 10867982 DOI: 10.1007/s002130000391] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
The present experiments were conducted to investigate effects of alpha-amino-3-hydroxy-5-methyl-4-isoxazoleprionic acid (AMPA)/kainate receptor blockade (CNQX, NBQX) on locomotor responses to D2/3 (7-OH-DPAT) and D1 [(+)-SKF 38393] dopamine receptor agonists in the nucleus accumbens (NAS) core and shell. CNQX (0.25-0.5 microgram) microinjected into the NAS core or shell did not affect baseline locomotor activity. 7-OH-DPAT (2.5-5 micrograms) decreased locomotor activity. Co-administration of CNQX (0.5 microgram) increased the effects of 7-OH-DPAT (5 micrograms) in the NAS core and shell. A similar increase was observed with NBQX (0.5 microgram) in the NAS shell. (+)-SKF 38393 (5 micrograms) into the NAS core and shell increased locomotor activity after 30 min; this effect was not altered by CNQX (0.5 microgram). As the D2/3 dopamine agonist (-)-quinpirole (2 micrograms) increased effects of (+)-SKF 38393 (5 micrograms) in NAS shell but not core, lack of site-selective effects of (+)-SKF-38393 and of 7-OH-DPAT within NAS is not attributable to drug diffusion. The previous observation that glutamate effects on locomotor activity depend on the relative involvement of D1 or D2/3 dopamine receptors in the NAS was based on the dopamine-depletion model. The present results demonstrate differential interactions of AMPA receptor blockade with dopamine agonists in "dopamine-intact" animals.
Collapse
|
94
|
Choi KH, Song HY, Shin SK, Noh H, Kang SW, Kim JH, Lee HY, Han DS. Influence of apolipoprotein E genotype on lipid and lipoprotein levels in continuous ambulatory peritoneal dialysis patients. ADVANCES IN PERITONEAL DIALYSIS. CONFERENCE ON PERITONEAL DIALYSIS 2000; 15:243-6. [PMID: 10682111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Abstract
Apolipoprotein (Apo) E has an important role in triglyceride (TG)-rich lipoprotein metabolism, and the genotype of Apo E is associated with premature coronary artery disease. Patients undergoing continuous ambulatory peritoneal dialysis (CAPD) develop various abnormalities of lipid metabolism and are prone to develop accelerated atherosclerosis. To investigate the distribution of Apo E genotype, and to evaluate the influence of Apo E polymorphism on lipid metabolism in CAPD patients, we measured Apo E genotypes, serum lipid, and lipoprotein levels in 54 CAPD patients (M:F = 1:1). The most common genotype of Apo E in the CAPD patients was E 3/3, found in 68.5%. The frequencies of the other genotypes were E 2/3, found in 14.8%, and E 4/3, found in 16.7%. No genotypic differences in Apo E were seen in the patients with regard to the presence of diabetes, the level of parathyroid hormone, or the transport characteristics of the peritoneal membrane. When comparing lipid levels by Apo E genotype, the total cholesterol and TG levels of E 2/3 patients were significantly higher than those of E 3/3 or E 4/3 patients. The differences in high-density or low-density lipoprotein cholesterol levels by Apo E genotype were not significant. In comparing lipoprotein levels by Apo E genotype, the Apo B and lipoprotein (a) levels of E 2/3 patients were significantly lower than those of E 3/3 or E 4/3 patients. In conclusion, the Apo E 3/3 genotype seems to be the most common genotype in CAPD patients, and the Apo E 2/3 genotype appears to be associated with high cholesterol and TG levels. These results demonstrate the need for further prospective studies in these subjects aimed at elucidating the impact of genetic variation at the Apo E locus on the development of atherosclerosis.
Collapse
|
95
|
Kim WH, Ghil KC, Lee JH, Yeo SH, Chun YJ, Choi KH, Kim DK, Kim MY. Involvement of p27(kip1) in ceramide-mediated apoptosis in HL-60 cells. Cancer Lett 2000; 151:39-48. [PMID: 10766421 DOI: 10.1016/s0304-3835(99)00402-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Ceramide acts as a mediator of apoptosis in various cell lines, but little is known regarding the molecular mechanism linked to the cell cycle. In the present study, we examined the expression of p27(kip1) and its relationship to apoptosis induced by ceramide. We demonstrated that treatment of HL-60 cells with C6-ceramide resulted in G1 phase elevation followed by apoptotic cleavage associated with increase in the level of cdk inhibitor p27(kip1). Ceramide inhibited the kinase activities of cdk2 and cdk4 within 24 h of treatment. Ceramide-induced inhibition of cdk2 and cdk4 kinase activities was accompanied by increase of p27(kip1) in the cdks complexes. In addition, we have shown that both the cell death and expression of p27(kip1) protein induced by ceramide were significantly decreased in HL-60 cells overexpressing bcl-2. Furthermore, ceramide induced a significant increase in Bax protein expression coincided with increase in p27(kip1) protein level. These findings indicate that p27(kip1) may play important roles in mediating ceramide-induced apoptosis and its expression can be regulated by Bax and Bcl-2.
Collapse
|
96
|
Bae JW, Choi KH, Kim HG, Park SH. The detection of circulating breast cancer cells in peripheral blood by reverse transcriptase-polymerase chain reaction. J Korean Med Sci 2000; 15:194-8. [PMID: 10803697 PMCID: PMC3054626 DOI: 10.3346/jkms.2000.15.2.194] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [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
Some circulating cancer cells in the blood play a central role in the metastatic process and may have a major influence on patient progress. Their numbers can be very small and techniques for their detection need to be both sensitive and specific. Polymerase chain reaction (PCR) has been successfully used to detect small numbers of tumor cells in cancer. We used a reverse transcriptase-polymerase chain reaction (RT-PCR) to detect circulating breast cancer cells in venous blood samples before operations and assessed cytokeratin-19 (CK-19) and cytokeratin-20 (CK-20) as target mRNA markers in the blood of healthy donors (n=6) and breast cancer patients (n=30) with American Joint Committee on Cancer stages 0 to IIIa. CK-19 mRNA was expressed in all blood samples of healthy donors and patients. But CK-20 was the only mRNA marker not detected in the blood from healthy donors. Seven of 30 (23%) venous blood isolates of breast cancer patients yielded a CK-20 mRNA with positive results. There was no correlating CK-20 mRNA expression with stage and axillary lymph node status. In conclusion, CK-19 showed no diagnostic value as a mRNA marker in the detection of circulating cancer cells by RT-PCR assay because this was expressed in the blood of healthy donors. CK-20 mRNA was an useful marker to detect circulating cancer cells in breast cancers.
Collapse
|
97
|
Song HY, Hwang JH, Noh H, Shin SK, Choi DH, Shim WH, Lee HY, Cho SY, Han DS, Choi KH. The prevalence and associated risk factors of renal artery stenosis in patients undergoing cardiac catheterization. Yonsei Med J 2000; 41:219-25. [PMID: 10817023 DOI: 10.3349/ymj.2000.41.2.219] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
Renal artery stenosis may be a cause of hypertension and a potential contributor to progressive renal insufficiency. However, the prevalence of renal artery disease in a general population is poorly defined. The purposes of this study were to evaluate the prevalence of angiographically-determined renal artery narrowing in a patient population undergoing routine cardiac catheterization, and to identify the risk factors for renal artery stenosis. After left ventriculography, abdominal aortography was performed to screen for the presence of renal artery stenosis. A total of 427 patients (274 males, 153 females) were studied and the mean age was 59 years. Renal artery narrowing was identified in 10.5% of patients. Significant (> or = 50% diameter narrowing) renal artery stenosis was found in 24 patients (5.6%) and insignificant stenosis was found in 21 patients (4.9%). Significant unilateral stenosis was present in 4.2% of patients and bilateral stenosis was present in 1.4%. The stem of the renal artery was a more common site of stenosis in 62.2% of patients than in the ostium (37.8%), but the severity of stenosis was not significantly different according to the site of stenosis. By univariate and multivariate logistic regression analysis, the association of clinical variables with renal artery stenosis was assessed. Multivariable predictors included age, hypertension and peripheral vascular disease (p < 0.05). The variables such as sex, smoking history, hyperlipidemia, renal insufficiency, as well as the presence of obesity, severity of coronary heart disease and D.M., were not associated. In conclusion, the prevalence of angiographically-determined renal artery narrowing in a patient population undergoing cardiac catheterization is 10.5%. Old age, hypertension and evidence of peripheral vascular disease represent the predictors of renal artery stenosis.
Collapse
|
98
|
Choi KH, Laursen RA. Amino-acid sequence and glycan structures of cysteine proteases with proline specificity from ginger rhizome Zingiber officinale. EUROPEAN JOURNAL OF BIOCHEMISTRY 2000; 267:1516-26. [PMID: 10691991 DOI: 10.1046/j.1432-1327.2000.01152.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The ginger proteases (GP-I and GP-II), isolated from the ginger rhizome Zingiber officinale, have an unusual substrate specificity preference for cleaving peptides with a proline residue at the P2 position. The complete amino-acid sequence of GP-II, a glycoprotein containing 221 amino acids, and about 98% that of GP-I have been determined. Both proteases, which are 82% similar, have cysteine residues at positions 27 and histidines at position 161, corresponding to the essential cysteine-histidine diads found in the papain family of cysteine proteases, and six corresponding cysteine residues that form the three invariant disulfide linkages seen in this family of proteins. The sequence homology with other members (papain, bromelain, actinidin, protease omega, etc.) of this family is approximately 50%. GP-II has two predicted glycosylation sites at Asn99 and Asn156. Analyisis by electrospray and collision-induced dissociation MS showed that both sites were occupied by the glycans (Man)3(Xyl)1(Fuc)1(GlcNAc)2 and (Man)3(Xyl)1(Fuc)1(GlcNAc)3, in a ratio of approximately 7 : 1. Both glycans are xylose containing biantennary complex types that share the common core structural unit, Man1-->6(Man1-->3) (Xyl1-->2)Man1-->4GlcNAc1-->4(Fuc1-->3)GlcNAc for the major form, with an additional N-acetylglucosamine residue being linked, in the minor form, to one of the terminal mannose units of the core structure.
Collapse
|
99
|
Lee BY, Jee WH, Kim JM, Kim BS, Choi KH. Incidence and significance of demonstrating the meniscofemoral ligament on MRI. Br J Radiol 2000; 73:271-4. [PMID: 10817042 DOI: 10.1259/bjr.73.867.10817042] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
The aim was to evaluate how often MRI can detect the meniscofemoral ligament and if there is any relationship with the presence of lateral meniscal tears. Sagittal and coronal MR images of 138 patients with arthroscopically proven meniscal tears were included in this study. MR images were retrospectively reviewed for the presence of a meniscofemoral ligament and a lateral meniscal tear. The chi 2 test was used for statistical analysis. Either one or both meniscofemoral ligaments were shown in 114 (83%) of 138 patients on MR images. In 61 cases with a lateral meniscal tear, the meniscofemoral ligament was present in 82% (50/61) and absent in 18% (11/61). In 77 cases without lateral meniscal tear, the meniscofemoral ligament was present in 83% (64/77) and absent in 17% (13/77). A significant correlation was not established between the meniscofemoral ligament and lateral meniscal tear (p = 0.85).
Collapse
|
100
|
Kim YS, Han SJ, Ryu JH, Choi KH, Hong YS, Chung YH, Perrot S, Raibaud A, Brey PT, Lee WJ. Lipopolysaccharide-activated kinase, an essential component for the induction of the antimicrobial peptide genes in Drosophila melanogaster cells. J Biol Chem 2000; 275:2071-9. [PMID: 10636911 DOI: 10.1074/jbc.275.3.2071] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Eukaryotic organisms use a similar Rel/NF-kappaB signaling cascade for the induction of innate immune genes. In Drosophila, lipopolysaccharide (LPS) signal-induced activation of the Rel/NF-kappaB family transcription factors is an essential step in the transcriptional activation of inducible antimicrobial peptide genes. However, the mechanism by which the LPS-induced signaling pathway proceeds remains largely unknown. Here we have cloned a novel Drosophila LPS-activated kinase (DLAK) that is structurally related to mammalian IkappaB kinases. DLAK is expressed and transiently activated in LPS-responsive Drosophila cells following LPS stimulation. Furthermore, DLAK can interact with Cactus, a Drosophila IkappaB and phosphorylate recombinant Cactus, in vitro. Overexpression of dominant-negative mutant DLAK (DLAK(K50A)) blocks LPS-induced Cactus degradation. DLAK-bound Cactus can be degraded in a LPS signal-dependent fashion, whereas the DLAK(K50A) mutant-bound Cactus is completely resistant to degradation in the presence of LPS. The DLAK(K50A) mutant also inhibits nuclear kappaB binding activity and kappaB-dependent diptericin reporter gene activity in a dose-dependent manner, but the kappaB-dependent diptericin reporter gene activity can be rescued by overexpression of wild type DLAK. Moreover, mRNA analysis of various kappaB-dependent antimicrobial peptide genes shows that LPS inducibility of these genes is greatly impaired in cells overexpressing DLAK(K50A). These results establish that DLAK is a novel LPS-activated kinase, which is an essential signaling component for the induction of antimicrobial peptide genes following LPS treatment in Drosophila cells.
Collapse
|