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Lee SY, Lee SH, Akuta K, Uda M, Song CW. Acute histological effects of interstitial hyperthermia on normal rat brain. Int J Hyperthermia 2000; 16:73-83. [PMID: 10669318 DOI: 10.1080/026567300285439] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022] Open
Abstract
Histological changes in the brains of Fischer rats at different times after interstitial heating with various thermal doses were studied. The brains, subjected to sham-heating, and heating at 39 and 40 degrees C for 30 min showed mild capillary congestion and minimal vacuolation at 4, 24 and 72 h. In the brains heated to 41, 42 and 43 degrees C for 30 min, there was local vascular congestion, petechiae, vacuolation and cellular shrinkage with nuclear pyknosis at 4 h; enhanced congestion and petechiae, acute cellular necrosis, infiltration of polymorphonuclear leukocytes and marked vacuolation at the margin at 24h; total coagulative necrosis of all parenchymal and vascular elements, early liquefaction necrosis and vascular hyperplasia at the margin at 72 h; enhanced vascular hyperplasia at the margin at 120 h and 168 h. The threshold thermal dose for the histopathological damage in the rat brain was heating at 41 degrees C for 30 min.
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1177
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Rha SE, Ha HK, Lee SH, Kim JH, Kim JK, Kim JH, Kim PN, Lee MG, Auh YH. CT and MR imaging findings of bowel ischemia from various primary causes. Radiographics 2000; 20:29-42. [PMID: 10682769 DOI: 10.1148/radiographics.20.1.g00ja0629] [Citation(s) in RCA: 229] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Ischemic bowel disease represents a broad spectrum of diseases with various clinical and radiologic manifestations, which range from localized transient ischemia to catastrophic necrosis of the gastrointestinal tract. The primary causes of insufficient blood flow to the intestine are diverse and include thromboembolism, nonocclusive causes, bowel obstruction, neoplasms, vasculitis, abdominal inflammatory conditions, trauma, chemotherapy, radiation, and corrosive injury. Computed tomography (CT) or magnetic resonance (MR) imaging can demonstrate the ischemic bowel segment and may be helpful in determining the primary cause. The CT and MR imaging findings include bowel wall thickening with or without the target sign, intramural pneumatosis, mesenteric or portal venous gas, and mesenteric arterial or venous thromboembolism. Other CT findings include engorgement of mesenteric veins and mesenteric edema, lack of bowel wall enhancement, increased enhancement of the thickened bowel wall, bowel obstruction, and infarction of other abdominal organs. However, regardless of the primary cause, the imaging findings of bowel ischemia are similar. Furthermore, the bowel changes simulate inflammatory or neoplastic conditions. Understanding the pathogenesis of various conditions leading to mesenteric ischemia helps the radiologist recognize ischemic bowel disease and avoid delayed diagnosis, unnecessary surgery, or less than optimal management.
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1178
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Park JE, Lee WH, Hwang TH, Chu JA, Kim S, Choi YH, Kim JS, Kim DK, Lee SH, Hong KP, Seo JD, Lee WR. Aging affects the association between endothelial nitric oxide synthase gene polymorphism and acute myocardial infarction in the Korean male population. Korean J Intern Med 2000; 15:65-70. [PMID: 10714094 PMCID: PMC4531736 DOI: 10.3904/kjim.2000.15.1.65] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
OBJECTIVES The aging process affects responsiveness and other functions of endothelium and vascular smooth muscle cells, predisposing the old vessels to the development of atherosclerotic lesions. Endothelial nitric oxide synthase (ecNOS) gene polymorphisms were shown to affect the occurrence of acute myocardial infarction (AMI). We hypothesized that aging may affect the association between the ecNOS gene polymorphism and AMI. METHODS We investigated the age-related distribution of the ecNOS gene a/b polymorphism in 121 male AMI patients and 206 age-matched healthy male controls. RESULTS The aa, ab and bb genotypes were found in 1, 49 and 156 cases among the control subjects and 5, 23 and 93 cases among the AMI patients, respectively. There was a significant correlation between the ecNOS polymorphism and AMI (p = 0.045). When the correlation was analyzed by age, the significance remained only in the group below the age of 51 (p = 0.009). The proportion of smokers was increased in the young patients when compared to the old patients (p = 0.033), indicating that smoking also has greater effect on the younger population. The incidences of hypertension and diabetes mellitus, however, were similar in both populations. CONCLUSION Our work provides the first evidence that links ecNOS polymorphism to the risk of AMI in relation to age. Young persons who smoke or have ecNOSaa genotype may have an increased risk of developing AMI. The functional as well as structural changes associated with aging in the vascular endothelium may mask the effect of the ecNOS polymorphism in the development of AMI in old persons.
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1179
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Park CH, Lee YJ, Lee SH, Choi SH, Kim HS, Jeong SJ, Kim SS, Suh YH. Dehydroevodiamine.HCl prevents impairment of learning and memory and neuronal loss in rat models of cognitive disturbance. J Neurochem 2000; 74:244-53. [PMID: 10617126 DOI: 10.1046/j.1471-4159.2000.0740244.x] [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: 11/20/2022]
Abstract
We previously reported that dehydroevodiamine.HCl (DHED) has anticholinesterase and antiamnesic activities. To verify the effects of DHED on cognitive deficits further, we tested it on the scopolamine-induced amnesia model of the rat using the passive avoidance and eight-arm radial maze tests. A single (20 mg/kg p.o.) and repeated (10 mg/kg p.o.) administrations of DHED could significantly reverse the latency time shortened by scopolamine (1 mg/kg i.p.) to control level. The impaired spatial working memory induced by scopolamine (1 mg/kg i.p.) was also improved significantly by a single injection (6.25 mg/kg i.p.) and repeated administrations of DHED (10 mg/kg p.o.) in the eight-arm radial maze test. In addition, we examined the effects of DHED on the memory impairment and the histological changes of the brain after unilateral electrolytic lesion of the entorhinal cortex (EC) and middle cerebral artery occlusion in rats. The cognitive deficits caused by EC lesion and middle cerebral artery occlusion were improved significantly by repeated administrations of DHED (6.25 mg/kg i.p.) after EC lesion or ischemic insult once a day for 7 days in the passive avoidance test. Histological analysis showed that the neuronal loss in the DHED-treated group was notably reduced in the hippocampal area (CA1) of ischemic rats and in the dentate gyrus and hippocampal area (CA1 and CA3) of EC-lesioned rats compared with the nontreated group. The infarction area was decreased significantly by a single administration of DHED (6.25 mg/kg i.p.) 30 min before ischemic insult for 6 h. These results suggest that DHED might be an effective drug for not only the Alzheimer's disease type, but also the vascular type of dementia.
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1180
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Min JK, Byun JY, Lee SH, Hong YS, Park SH, Cho CS, Kim HY. Urinary bladder involvement in patients with systemic lupus erythematosus: with review of the literature. Korean J Intern Med 2000; 15:42-50. [PMID: 10714091 PMCID: PMC4531746 DOI: 10.3904/kjim.2000.15.1.42] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
OBJECTIVES To investigate the etiologies of urinary bladder involvement in patients with systemic lupus erythematosus (SLE), the clinicoradiologic features of gastrointestinal tract manifestations and clinical outcomes in patients with lupus cystitis accompanied by gastrointestinal manifestations. METHODS We conducted a retrospective chart review on 413 patients with SLE. Patients were selected for review on the basis of lower urinary tract symptoms including urinary frequency, urgency and urinary incontinence. Radiologic studies were analyzed in patients with lupus cystitis. RESULTS Ten consecutive patients, complicated with lower urinary tract symptoms, were identified. Underlying etiologies were as follows: lupus cystitis in five, neurogenic dysfunction secondary to transverse myelitis in three, cyclophosphamide-induced cystitis in one and tuberculous cystitis in one patient. All patients with lupus cystitis showed gastrointestinal manifestations, such as abdominal pain, nausea, vomiting and/or diarrhea during the periods of cystitis symptoms. In all patients with lupus cystitis, paralytic ileus was demonstrated on plain abdominal X-ray and ascites, bilateral hydroureteronephrosis and thickened bladder wall were identified on abdominal ultrasound or CT. Abdominal CT revealed bowel wall thickening in four of the five patients. The main sites of thickened bowel on abdominal CT were territory supplied by superior mesenteric artery. Two of five patients with lupus cystitis expired during the follow-up period. CONCLUSION Diverse etiologies may cause lower urinary tract symptoms in patients with SLE. Lupus cystitis is strongly associated with gastrointestinal involvement and abdominal CT can be a useful radiologic tool to investigate the gastrointestinal tract involvement in patients with lupus cystitis.
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1181
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Abstract
We review the anatomical and archaeological evidence for an early population bottleneck in humans and bracket the time when it could have occurred. We outline the subsequent demographic changes that the archaeological evidence of range expansions and contractions address, and we examine how inbreeding effective population size provides an alternative view of past population size change. This addresses the question of other, more recent, population size bottlenecks, and we review nonrecombining and recombining genetic systems that may reflect them. We examine how these genetic data constrain the possibility of significant population size bottlenecks (i.e., of sufficiently small size and/or long duration to minimize genetic variation in autosomal and haploid systems) at several different critical times in human history. Different constraints appear in nonrecombining and recombining systems, and among the autosomal loci most are incompatible with any Pleistocene population size expansions. Microsatellite data seem to show Pleistocene population size expansions, but in aggregate they are difficult to interpret because different microsatellite studies do not show the same expansion. The archaeological data are only compatible with a few of these analyses, most prominently with data from Alu elements, and we use these facts to question whether the view of the past from analysis of inbreeding effective population size is valid. Finally, we examine the issue of whether inbreeding effective population size provides any reasonable measure of the actual past size of the human species. We contend that if the evidence of a population size bottleneck early in the evolution of our lineage is accepted, most genetic data either lack the resolution to address subsequent changes in the human population or do not meet the assumptions required to do so validly. It is our conclusion that, at the moment, genetic data cannot disprove a simple model of exponential population growth following a bottleneck 2 MYA at the origin of our lineage and extending through the Pleistocene. Archaeological and paleontological data indicate that this model is too oversimplified to be an accurate reflection of detailed population history, and therefore we find that genetic data lack the resolution to validly reflect many details of Pleistocene human population change. However, there is one detail that these data are sufficient to address. Both genetic and anthropological data are incompatible with the hypothesis of a recent population size bottleneck. Such an event would be expected to leave a significant mark across numerous genetic loci and observable anatomical traits, but while some subsets of data are compatible with a recent population size bottleneck, there is no consistently expressed effect that can be found across the range where it should appear, and this absence disproves the hypothesis.
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1182
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Ueng KC, Lee SH, Wu DJ, Lin CS, Chang MS, Chen SA. Radiofrequency catheter modification of atrioventricular junction in patients with COPD and medically refractory multifocal atrial tachycardia. Chest 2000; 117:52-9. [PMID: 10631199 DOI: 10.1378/chest.117.1.52] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
BACKGROUND Multifocal atrial tachycardia (MAT) is a difficult clinical problem generally associated with acute cardiorespiratory illness. The purpose of this study was to assess the feasibility and clinical usefulness of atrioventricular (AV) junction modification as a nonpharmacologic therapy for medically refractory MAT. METHODS AND RESULTS Thirteen patients with COPD and medically refractory MAT underwent AV junction modification. Complications and outcome of this procedure were monitored. Subjective perceptions of quality of life assessed by a semiquantitative questionnaire and cardiac performance study were obtained before ablation (baseline) and 1 and 6 months after ablation. Radiofrequency energy was applied until the average ventricular rate fell to < 100 beats/min. Ablation procedures controlled the ventricular response in 11 of 13 patients (84%). One patient had unsuccessful modification. Another patient developed delayed complete AV block on the second day after ablation. In these 13 patients, average ventricular rate was reduced from a mean of 145 +/- 11 to 89 +/- 22 beats/min immediately after the ablation (p < 0.01). One patient had recurrent symptomatic MAT at 1 month after ablation; this patient underwent a second procedure without late recurrence. All patients were followed up for at least 6 months (mean, 11 +/- 5 months; range, 6 to 18 months). General quality of life and frequency of significant symptoms improved significantly in patients with successful modification at 1 and 6 months. The left ventricular ejection fraction increased significantly after ablation (44.5 +/- 7.3% at baseline, 49.4 +/- 4. 2% at 1 month, and 50.0 +/- 4.9% at 6 months; all p < 0.05). However, right ventricular ejection fraction remained unchanged (34.7 +/- 6. 2% at baseline, 35.7 +/- 4.4% at 1 month, and 34.3 +/- 4.6% at 6 months; all p > 0.05). The consumption of health-care resources (including frequency of hospital admission and emergency department attendance, antiarrhythmic drug trials) decreased significantly 6 months after AV junction modification. Pulmonary function and theophylline level remained unchanged during follow-up. CONCLUSIONS AV junction modification offers an effective therapy for controlling ventricular rate in medically refractory MAT. This procedure improves the quality of life and left ventricular function in selected patients with symptomatic and medically refractory MAT.
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1183
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Lee SH, Shin MS, Kim HS, Park WS, Kim SY, Jang JJ, Rhim KJ, Jang J, Lee HK, Park JY, Oh RR, Han SY, Lee JH, Lee JY, Yoo NJ. Somatic mutations of Fas (Apo-1/CD95) gene in cutaneous squamous cell carcinoma arising from a burn scar. J Invest Dermatol 2000; 114:122-6. [PMID: 10620127 DOI: 10.1046/j.1523-1747.2000.00819.x] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Fas (Apo-1/CD95) is a cell-surface receptor involved in cell death signaling, and recent reports have suggested that defects within the Fas receptor pathway such as Fas mutation play an important part in the development and progression of human tumors. Burn scar-related squamous cell carcinoma of skin is a unique subtype of cutaneous squamous cell carcinoma, and tends to be more aggressive in nature than conventional squamous cell carcinoma. The molecular mechanisms underlying the development and progression of burn scar-related squamous cell carcinoma, however, are not clear. In this study, we analyzed the entire coding region and all splice sites of the Fas gene for the detection of the somatic mutations in a series of 50 conventional squamous cell carcinomas and 21 burn scar-related squamous cell carcinomas by polymerase chain reaction, single strand conformation polymorphism, and DNA sequencing. We detected mis-sense mutations in three of 21 burn scar-related squamous cell carcinomas (14.3%), whereas no mutation was detected in 50 conventional squamous cell carcinomas. Of the three Fas mutations detected in the burn scar-related squamous cell carcinomas, one was found in Fas ligand-binding domain, another one was identified in the death domain known to be involved in the transduction of an apoptotic signal, and the other one was found in the transmembrane domain. Our data show that some burn scar-related squamous cell carcinomas have Fas gene mutations in important regions for the apoptosis function and suggest that these mutations might be involved in the pathogenesis of burn scar-related squamous cell carcinomas. In addition, our results provide an important clue to understanding the difference between burn scar-related squamous cell carcinoma and conventional squamous cell carcinoma at the molecular level.
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1184
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Lee A, Tsang KK, Lee SH, To CY. A "Healthy Schools" program in Hong Kong: enhancing positive health behavior for school children and teachers. EDUCATION FOR HEALTH (ABINGDON, ENGLAND) 2000; 13:399-403. [PMID: 14742066 DOI: 10.1080/135762800750059516] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
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1185
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Kim W, Min S, Cho M, Youn J, Min J, Lee S, Park S, Cho C, Kim H, Kim WU, Min SY, Cho ML, Min DJ, Lee SH, Park SH, Cho CS, Kim HY. The role of IL-12 in inflammatory activity of patients with rheumatoid arthritis (RA). Clin Exp Immunol 2000; 119:175-81. [PMID: 10606980 PMCID: PMC1905529 DOI: 10.1046/j.1365-2249.2000.01095.x] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The aim of this study was to investigate the role of IL-12 in patients with RA. IL-12 (p70) and its associated cytokines were measured in sera and synovial fluid (SF) using an enzyme-linked immunosorbent method. Seven American College of Rheumatology (ACR) core set measures as well as IL-12 levels were sequentially monitored at the commencement and 4 months after treatment with a low-dose steroid and disease-modifying anti-rheumatic drugs (DMARDs). In sera, 64 (42.2%) of 152 RA patients had detectable concentrations of IL-12 (p70), whereas one (1.4%) of 69 osteoarthritis (OA) patients and five (10%) of 50 healthy controls had detectable IL-12 (P < 0.001). The median level of circulating IL-12 was also higher in RA patients (P < 0.001). In SF, the number of patients with detectable IL-12 and the median IL-12 levels were significantly higher in RA patients (n = 53) than in OA patients (n = 22). In paired samples (n = 53) of sera and SF from RA patients, IL-12 levels were higher in the SF than in sera (P < 0.001). Patients with detectable IL-12 (n = 51) in sera had higher tender joint scores (P = 0.003), swollen joint scores (P < 0.001) and C-reactive protein (CRP; P = 0.036), than those without (n = 55). Four months after treatment with DMARDs, the improved group showed a larger IL-12 decrease than the non-improved group (P = 0.017). The levels of IL-12 correlated positively with those of IL-2, interferon-gamma, IL-6, and tumour necrosis factor-alpha, but were correlated inversely with those of IL-10. Our results demonstrate that IL-12 levels reflect RA disease activity and that IL-12 is involved in the production of proinflammatory cytokines. An IL-12 blockade could be useful for the treatment of RA.
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1186
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Lee SH, Lim HH, Lee HM, Choi JO. Expression of human beta-defensin 1 mRNA in human nasal mucosa. Acta Otolaryngol 2000; 120:58-61. [PMID: 10779187 DOI: 10.1080/000164800760370846] [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: 10/27/2022]
Abstract
Antimicrobial peptides are cationic proteins that are found in a wide range of organisms. Recent reports suggested that human beta-defensin 1 (hBD-1), a prominent group of antimicrobial peptides, is an important component of the innate immune response, particularly at mucosal surfaces that are vulnerable to colonization by potential pathogens. Therefore, hBD-1 may participate in providing intrinsic nasal mucosal defence against microbial infections. The present study aimed to look for hBD-1 mRNA in human nasal mucosa without obvious signs of inflammation. Total RNA was isolated from human inferior turbinate mucosa and hBD-1 mRNA was detected in these tissues by using reverse transcription and polymerase chain reaction (RT-PCR). By in situ hybridization, hBD-1 mRNA was predominantly localized in superficial epithelial cells and submucosal glandular epithelium of human inferior turbinate mucosa. These data suggest that nasal epithelia and submucosal glands may secrete hBD-1, contributing to the mucosal defences of the nose.
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1187
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Jung JI, Park SH, Park JG, Lee SH, Lee KY, Hahn ST. Teratoma with malignant transformation in the anterior mediastinum: a case report. Korean J Radiol 2000; 1:162-4. [PMID: 11752948 PMCID: PMC2718186 DOI: 10.3348/kjr.2000.1.3.162] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Malignant transformation of teratoma in the anterior mediastinum is rare; the mass usually has a long history and is seen in older patients. We report a case of teratoma with malignant transformation in the anterior mediastinum, complicated by rupture. CT revealed a lobulated, inhomogeneous cystic mass with a fat component and wall calcifications. The lateral wall was disrupted and consolidation in the adjacent left upper lobe was noted, suggesting rupture. A heterogeneously enhanced solid portion, obliterating the fat plane between the mass and the great vessels was present in the medial aspect of the mass, and pathologic examination demonstrated the presence of adenocarcinoma.
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1188
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Naulleau PP, Goldberg KA, Lee SH, Chang C, Attwood D, Bokor J. Extreme-ultraviolet phase-shifting point-diffraction interferometer: a wave-front metrology tool with subangstrom reference-wave accuracy. APPLIED OPTICS 1999; 38:7252-7263. [PMID: 18324274 DOI: 10.1364/ao.38.007252] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The phase-shifting point-diffraction interferometer (PS/PDI) was recently developed and implemented at Lawrence Berkeley National Laboratory to characterize extreme-ultraviolet (EUV) projection optical systems for lithography. Here we quantitatively characterize the accuracy and precision of the PS/PDI. Experimental measurements are compared with theoretical results. Two major classes of errors affect the accuracy of the interferometer: systematic effects arising from measurement geometry and systematic and random errors due to an imperfect reference wave. To characterize these effects, and hence to calibrate the interferometer, a null test is used. This null test also serves as a measure of the accuracy of the interferometer. We show the EUV PS/PDI, as currently implemented, to have a systematic error-limited reference-wave accuracy of 0.0028 waves (lambda/357 or 0.038 nm at lambda = 13.5 nm) within a numerical aperture of 0.082.
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1189
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Lee SH, Hava DL, Waldor MK, Camilli A. Regulation and temporal expression patterns of Vibrio cholerae virulence genes during infection. Cell 1999; 99:625-34. [PMID: 10612398 DOI: 10.1016/s0092-8674(00)81551-2] [Citation(s) in RCA: 249] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The temporal expression patterns of the critical Vibrio cholerae virulence genes, tcpA and ctxA, were determined during infection using a recombinase reporter. TcpA was induced biphasically in two temporally and spatially separable events in the small intestine, whereas ctxA was induced monophasically only after, and remarkably, dependent upon, tcpA expression; however, this dependence was not observed during in vitro growth. The requirements of the virulence regulators, ToxR, TcpP, and ToxT, for expression of tcpA and ctxA were determined and were found to differ significantly during infection versus during growth in vitro. These results illustrate the importance of examining virulence gene expression in the context of bona fide host-pathogen interactions.
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1190
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Abstract
Microglia, brain resident macrophages, are activated in brain injuries and several neurodegenerative diseases. However, microglial activators that are produced in the brain are not yet defined. In this study, we showed that gangliosides, sialic acid-containing glycosphingolipids, could be a microglial activator. Gangliosides induced production of nitric oxide (NO) and tumor necrosis factor-alpha (TNF-alpha) and expression of cyclooxygenase-2 (COX-2). The effect of gangliosides on NO release increased dose-dependently in the range of 10-100 microgram/ml; however, the effect decreased at concentrations higher than 200 microgram/ml. Specific types of gangliosides showed differential effects on microglial activation. Similar to gangliosides, GT1b induced production of NO and TNF-alpha and expression of COX-2. However, GM1 and GD1a induced expression of COX-2 but had little effect on NO and TNF-alpha release. The effect of gangliosides and GT1b on NO release was reduced in the presence of neuraminidase, which removes sialic acid residues from gangliosides and GT1b. Gangliosides activated extracellular signal-regulated kinase significantly but activated c-jun N-terminal kinase/stress-activated protein kinase and p38 relatively weakly. The inhibition of extracellular signal-regulated kinase by PD98059 reduced NO release from both gangliosides- and GT1b-treated microglia whereas inhibition of p38 by SB203580 increased it rather slightly. Gangliosides activated NF-kappaB, and N-acetyl cystein, an inhibitor of NF-kappaB, reduced NO release. These results suggest that gangliosides could be a microglial activator that functions via activation of mitogen-activated protein kinase and NF-kappaB.
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1191
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Hong ST, Lee M, Sung NJ, Cho SR, Chai JY, Lee SH. Usefulness of IgG4 subclass antibodies for diagnosis of human clonorchiasis. THE KOREAN JOURNAL OF PARASITOLOGY 1999; 37:243-8. [PMID: 10634040 PMCID: PMC2733201 DOI: 10.3347/kjp.1999.37.4.243] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The present study analyzed serum IgG subclass antibody reaction to major antigenic bands of Clonorchis sinensis to investigate improvement of its serodiagnosis. Of the four subclass antibodies, IgG1 and IgG2 antibodies were produced but not specific, IgG3 antibody was least produced, and IgG4 antibody was prominent and specific. The serum IgG antibody reaction to any of 43-50, 34-37, 26-28, and 8 kDa bands was found in 65.5% of 168 egg positive cases while IgG4 antibody reaction was found in 22.0% of them. The positive rates of IgG and IgG4 antibodies were directly correlated with the intensity of infection. All of the sera from heavily infected cases over EPG 5,000 showed positive reaction for specific IgG and IgG4 antibodies. The specific serum IgG4 antibody disappeared within 6 months after treatment. The bands of 35 kDa and 67 kDa cross-reacted with IgG antibodies but not with IgG4 antibodies in sera of other trematode infections. The present findings suggest that serum IgG4 antibody reaction to 8 kDa band is specific but not sensitive. Any method to increase its sensitivity is required for improved serodiagnosis.
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1192
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Lee DS, Lee SH, Noh JG, Hong SD. Antibacterial activities of cryptotanshinone and dihydrotanshinone I from a medicinal herb, Salvia miltiorrhiza Bunge. Biosci Biotechnol Biochem 1999; 63:2236-9. [PMID: 10664860 DOI: 10.1271/bbb.63.2236] [Citation(s) in RCA: 101] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Cryptotanshinone and dihydrotanshinone I, constituents of a medicinal plant, Salvia miltiorrhiza Bunge, had antibacterial activity against a broad range of Gram positive bacteria. These compounds generated superoxide radicals in Bacillus subtilis lysates. A recombination-deficient mutant strain of B. subtilis was 2- to 8-fold more sensitive than a wild strain, and this hypersensitivity was reduced in the presence of dithiothreitol as an antioxidant. DNA, RNA, and protein syntheses in B. subtilis were non-selectively inhibited by these compounds. These results suggest that superoxide radicals are important in the antibacterial actions of the agents.
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1193
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Kim JA, Kang YS, Jung MW, Lee SH, Lee YS. Involvement of Ca2+ influx in the mechanism of tamoxifen-induced apoptosis in HepG2 human hepatoblastoma cells. Cancer Lett 1999; 147:115-23. [PMID: 10660097 DOI: 10.1016/s0304-3835(99)00284-0] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The signaling mechanism of tamoxifen (TAM)-induced apoptosis was investigated in HepG2 human hepatoblastoma cells which do not express the estrogen receptor (ER). TAM induced cytotoxicity and DNA fragmentation, a hallmark of apoptosis, in a dose-dependent manner. TAM increased the intracellular concentration of Ca2+. This effect was completely inhibited by the extracellular Ca2+ chelation with EGTA. TAM also induced a Mn2+ influx, indicating that TAM activated Ca2+ influx pathways. This action of TAM was significantly inhibited by flufenamic acid (FA), a known non-selective cation channel blocker. Quantitative analysis of apoptosis by flow cytometry revealed that treatment with either FA or BAPTA, an intracellular Ca2+ chelator, significantly inhibited TAM-induced apoptosis. These results suggest that intracellular Ca2+ signals may play a central role in the mechanism of the TAM-induced apoptotic cell death in ER-negative HepG2 cells.
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1194
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Kim TH, Choi EH, Ahn SK, Lee SH. Vascular tumors arising in port-wine stains: two cases of pyogenic granuloma and a case of acquired tufted angioma. J Dermatol 1999; 26:813-6. [PMID: 10659503 DOI: 10.1111/j.1346-8138.1999.tb02098.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Three female patients affected by intradermal vascular tumors were presented. The lesions were acquired and developed from preexisting port-wine stains (PWS). Among the three patients observed, two had a pyogenic granuloma (PG) and the third patients had tufted angiomas. As reported earlier, formation of a PG within the lesion of a PWS supports the assumption that arteriovenous anastomoses are associated with its pathogenesis. Occurrence of tufted angioma from a PWS, as well as coexisting but separate PWS has been reported. However, the tufted angiomas of our patient were located in different sites, one in the PWS and others separate from the PWS. This has never previously been reported.
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Hwang SM, Lee SH, Ahn SK. Pincer nail deformity and pseudo-Kaposi's sarcoma: complications of an artificial arteriovenous fistula for haemodialysis. Br J Dermatol 1999; 141:1129-32. [PMID: 10606867 DOI: 10.1046/j.1365-2133.1999.03219.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Pseudo-Kaposi's sarcoma which develops due to arteriovenous fistulae for haemodialysis is relatively well known. In contrast, nail changes associated with pseudo-Kaposi's sarcoma or venous hypertension are rare. We report a novel case of pincer nail deformity associated with pseudo-Kaposi's sarcoma and venous hypertension, complications of an arteriovenous fistula for haemodialysis, and review eight similar cases reported in the literature. Most of the subjects presented with similar findings, having circulatory disturbance due to an arteriovenous fistula and/or increased venous pressure, and swelling, discoloration and papules/nodules of the skin distal to the shunt. Of the nine patients, three had overcurvature of the nails, in which the lateral edge of the nail pressed deeply into the lateral nail fold. Pincer nail deformity associated with pseudo-Kaposi's sarcoma after placement of an arteriovenous fistula may be relatively common and should be recognized as a specific sign of circulatory disturbance due to the arteriovenous fistula.
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1196
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Abstract
The ability of estrogen to modulate the expression of ventral and dorsal striatal dopamine receptors D(1), D(2,) and D(3) was examined in vivo using semi-quantitative in situ hybridization and ligand binding autoradiography. Two-week treatment with subcutaneous pellets of 17beta-estradiol (25 mg) downregulated D(2) dopamine receptor mRNA in both dorsal and ventral striatum (shell and core regions of nucleus accumbens). No significant changes in D(1) or D(3) mRNA expression were detected. Ligand binding autoradiography did not reveal changes in D(1), D(2,) or D(3) receptor protein expression. We also assessed the ability of 17beta-estradiol to regulate D(2) gene promoter activity in NB41A3 neuroblastoma cells that express this gene endogenously using co-transfections with an estrogen receptor expression vector. While a small fragment of the D(2) promoter could be activated 2.5-fold by estrogen, a larger portion of the D(2) gene was not regulated by this treatment. Estrogens do not appear to have a net effect on striatal dopamine receptor expression. The observed downregulation of D(2) receptor mRNA in the dorsal and ventral striatum in vivo could be secondary to the increased striatal dopamine release induced by estrogen. Synapse 34:222-227, 1999. Published 1999 Wiley-Liss, Inc.
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1197
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Chen YJ, Tai CT, Chiou CW, Wen ZC, Chan P, Lee SH, Chen SA. Inducibility of atrial fibrillation during atrioventricular pacing with varying intervals: role of atrial electrophysiology and the autonomic nervous system. J Cardiovasc Electrophysiol 1999; 10:1578-85. [PMID: 10636188 DOI: 10.1111/j.1540-8167.1999.tb00222.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
INTRODUCTION Patients receiving VVI pacemakers have a higher incidence of paroxysmal atrial fibrillation (AF) than those receiving DDD pacemakers. However, the mechanism behind the difference is not clear. The purpose of this study was to investigate whether atrial electrophysiology and the autonomic nervous system play a role in the occurrence of AF during AV pacing. METHODS AND RESULTS The study population consisted of 28 patients who had (group I, n = 15) or did not have (group II, n = 13) AF induced by a single extrastimulus during pacing with different AV intervals. Atrial pressure, atrial size, atrial effective refractory periods, and atrial dispersion were evaluated during pacing with different AV intervals. Twenty-four-hour heart rate variability and baroreflex sensitivity also were examined. Atrial pressure, atrial size, effective refractory periods in the right posterolateral atrium and distal coronary sinus, and atrial dispersion increased as the AV interval shortened from 160 to 0 msec. During AV pacing, group I patients had greater minimal (52+/-17 vs 25+/-7 msec; P < 0.005) and maximal (76+/-16 vs 36+/-9 msec; P < 0.005) atrial dispersion than group II patients. The differences in atrial size and atrial dispersion among different AV intervals were greater in patients with AF than in those without AF. Baroreflex sensitivity (6.6+/-1.7 vs 3.9+/-1.0; P < 0.00005), but not heart rate variability, was higher in patients with AF than in those without AF. CONCLUSION Abnormal atrial electrophysiology and higher vagal reflex activity can play important roles in the genesis of AF in patients receiving pacemakers.
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1198
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Zhao A, Lee SH, Mojena M, Jenkins RG, Patrick DR, Huber HE, Goetz MA, Hensens OD, Zink DL, Vilella D, Dombrowski AW, Lingham RB, Huang L. Resorcylic acid lactones: naturally occurring potent and selective inhibitors of MEK. J Antibiot (Tokyo) 1999; 52:1086-94. [PMID: 10695671 DOI: 10.7164/antibiotics.52.1086] [Citation(s) in RCA: 98] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A resorcylic acid lactone, L-783,277, isolated from a Phoma sp. (ATCC 74403) which came from the fruitbody of Helvella acetabulum, is a potent and specific inhibitor of MEK (Map kinase kinase). L-783,277 inhibits MEK with an IC50 value of 4 nM. It weakly inhibits Lck and is inactive against Raf, PKA and PKC. L-783,277 is an irreversible inhibitor of MEK and is competitive with respect to ATP. L-783,290, the trans-isomer of L-783,277, was isolated from the same culture and evaluated together with several semi-synthetic resorcylic acid lactone analogs. A preliminary structure-activity relationship is presented. Several independent cell-based assays have been carried out to study the biological activities of these resorcylic acid lactone compounds and a brief result summary from these studies is presented.
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1199
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Cho SR, Park YG, Moon HN, Lee SH, Hong ST. Karyotypes of Pneumocystis carinii derived from several mammals. THE KOREAN JOURNAL OF PARASITOLOGY 1999; 37:271-5. [PMID: 10634044 PMCID: PMC2733205 DOI: 10.3347/kjp.1999.37.4.271] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Pneumocystis carinii is the most important opportunistic pathogen of humans in the world. Pneumocystis carinii is experimentally detected in the lungs of rats, mice, rabbits, and monkeys, however, the organisms from different mammals are identical in microscopic morphology. The present study tried to find out more mammalian hosts of P. carinii and also to differentiate the organisms from different mammals by karyotyping. Rats, mice, hamsters, rabbits, cats, and dogs were successfully infected by P. carinii, but guinea pigs and pigs were not. Karyotype of P. carinii from rabbits showed similar size range of chromosomes with that of the prototype, but in different pattern. The patterns from cats and dogs were also different from that of rats. The present study confirms that cats and dogs are infected by P. carinii and at least total three karyotype strains of P. carinii are proven in Korea.
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1200
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Lee SH, Shin MS, Park WS, Kim SY, Kim HS, Lee JH, Han SY, Lee HK, Park JY, Oh RR, Jang JJ, Lee JY, Yoo NJ. Immunohistochemical localization of FAP-1, an inhibitor of Fas-mediated apoptosis, in normal and neoplastic human tissues. APMIS 1999; 107:1101-8. [PMID: 10660140 DOI: 10.1111/j.1699-0463.1999.tb01515.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Fas, a death receptor, is widely expressed in human tissue, but its expression, although a prerequisite for the induction of apoptosis, does not predict its biological function. To understand the mechanisms of Fas resistance in human tissues in vivo, we performed immunohistochemistry using an antibody against Fas-associated phosphatase-1 (FAP-1), which interacts with the cytosolic domain of Fas and inhibits Fas-mediated apoptosis. In normal human tissues, FAP-1 immunostaining was easily detected, for example, in renal tubules, skeletal muscle, myocardiocytes, pituitary gland, parathyroid gland, pancreatic islets, hepatocytes, testicular germ cells, prostatic glands, neurons, epithelium of fallopian tube, endometrial glands, trophoblasts, bronchial epithelial cells, and some types of gastrointestinal epithelial cells. In 123 (78%) of 158 cancers of various origins, including breast carcinomas, stomach carcinomas, colon carcinomas, lung carcinomas and several types of sarcomas, variable intensities of FAP-1 expression were evident. Taken together, these findings demonstrated that FAP-1 is widely expressed in normal human tissues and partly overlapped with Fas expression described in earlier reports, suggesting that FAP-1 may have an important role in the regulation of apoptosis in vivo. In addition, FAP-1 expression in cancers suggests that many cancers may be resistant to Fas-mediated apoptosis through the action of FAP-1 in vivo.
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