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John ER, Ahn H, Prichep L, Trepetin M, Brown D, Kaye H. Developmental equations for the electroencephalogram. Science 1980; 210:1255-8. [PMID: 7434026 DOI: 10.1126/science.7434026] [Citation(s) in RCA: 341] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Thirty-two linear regression equations predict the frequency composition of the electroencephalogram within four frequency bands, for four bilateral regions of the brain, as a function of age. Equations based on such data from large groups of healthy children in the United States and Sweden are closely similar. These equations describe the development of the electrical activity of the normal human brain, independent of cultural, ethnic, socioeconomic, or sex factors.
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Wityk RJ, Lehman D, Klag M, Coresh J, Ahn H, Litt B. Race and sex differences in the distribution of cerebral atherosclerosis. Stroke 1996; 27:1974-80. [PMID: 8898801 DOI: 10.1161/01.str.27.11.1974] [Citation(s) in RCA: 309] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
BACKGROUND AND PURPOSE The purpose of this study was to assess the influence of race, sex, and other risk factors on the location of atherosclerotic occlusive lesions in cerebral vessels. Previous angiographic studies of patients with stroke or transient ischemic attack (TIA) suggest that extracranial atherosclerosis is more common in whites and intracranial disease is more common in blacks. Noninvasive techniques such as duplex ultrasound, transcranial Doppler (TCD), and magnetic resonance angiography (MRA) allow vascular assessment of a more representative proportion of patients than does conventional angiography alone. METHODS Consecutive patients evaluated at a community hospital for stroke or TIA over a 2-year period were reviewed. Lesions were defined as a 50% or greater atherosclerotic stenosis by angiography, duplex ultrasound, or TCD, or a moderate stenosis by MRA. RESULTS Whites were more likely than blacks to have extracranial carotid artery lesions (33% versus 15%, P = .001), but the proportion of patients with intracranial lesions was similar (24% versus 22%). Men were more likely to have intracranial lesions than women (29% versus 14%, P = .03). When multivariate logistic regression analysis was used, white race was the only predictor for extracranial carotid artery lesions, and male sex was the only predictor for intracranial lesions. The cause of stroke/TIA was extracranial carotid artery disease in 8% and intracranial disease in 8% of all patients in the study. CONCLUSIONS The distribution of cerebral atherosclerosis is influenced by race and sex but not by other vascular risk factors. In our patient population, intracranial disease is as common a cause of cerebral ischemia as extracranial carotid disease.
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309 |
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John ER, Karmel BZ, Corning WC, Easton P, Brown D, Ahn H, John M, Harmony T, Prichep L, Toro A, Gerson I, Bartlett F, Thatcher F, Kaye H, Valdes P, Schwartz E. Neurometrics. Science 1977; 196:1393-410. [PMID: 867036 DOI: 10.1126/science.867036] [Citation(s) in RCA: 259] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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259 |
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Yi ES, Kim H, Ahn H, Strother J, Morris T, Masliah E, Hansen LA, Park K, Friedman PJ. Distribution of obstructive intimal lesions and their cellular phenotypes in chronic pulmonary hypertension. A morphometric and immunohistochemical study. Am J Respir Crit Care Med 2000; 162:1577-86. [PMID: 11029379 DOI: 10.1164/ajrccm.162.4.9912131] [Citation(s) in RCA: 182] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
We investigated the distribution of pulmonary arteriopathy in chronic pulmonary hypertension (PH) in a quantitative histopathologic study, using computer-assisted image analysis. We also examined the histologic manifestations and cellular phenotypes of various obstructive intimal lesions in PH with an immunohistochemical method. A total of 53 lungs removed at autopsy or explantation were obtained for the study from 51 documented cases of moderate to severe PH (15 cases of primary pulmonary hypertension [PPH], eight cases of Eisenmenger's syndrome [EISEN], 22 cases of chronic major-vessel thromboembolic disease [CTED], and three cases of PH associated with other known causes), and two unused donor lungs served as normal controls. Intimal thickening in PPH was most prominent in small pulmonary arteries and arterioles less than 200 micrometer in diameter. Plexiform lesions in PPH were associated with significantly smaller arteries than in EISEN. Arteries larger than 400 micrometer showed a significant intimal thickening only in CTED. Obstructive intimal lesions in PH comprised a morphologic spectrum with frequent intermediate forms between plexiform and thrombotic lesions. Most cells within various intimal lesions showed an immunoprofile of myofibroblasts that were positive for vimentin and alpha-smooth muscle actin, but negative for desmin and endothelial markers including Factor VIII, clonal designator (CD)31, and CD34. Endothelial markers were positive only in the single layer of cells lining slitlike lumens, when the latter were present. In conclusion, major types of PH had characteristic distribution patterns of obstructive intimal lesions, showing mainly a myofibroblastic phenotype and variable endothelial/vascular differentiation.
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Ahn H, Lindhagen J, Nilsson GE, Salerud EG, Jodal M, Lundgren O. Evaluation of laser Doppler flowmetry in the assessment of intestinal blood flow in cat. Gastroenterology 1985; 88:951-7. [PMID: 3156061 DOI: 10.1016/s0016-5085(85)80013-5] [Citation(s) in RCA: 158] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Laser Doppler flowmetry with a differential detector system has been used in the assessment of blood flow in the feline small intestine. Simultaneous mucosal and serosal laser Doppler flowmeter recordings were compared with total blood flow of a bowel segment measured by an optical drop-recorder unit in 6 cats. Blood flow through the muscularis layer was estimated using the 85Kr washout technique. A correlation coefficient of r = 0.96 (mucosal recordings = 90, serosal recordings = 80, p less than 0.001) was obtained between laser Doppler flowmeter output signals and total blood flow at different levels of vascular tone, regardless of whether the flowmeter recordings were made from the mucosal or the serosal side of the bowel wall. At intense vasodilation, the flowmeters showed a tendency to underestimate blood flow. The flowmeter signals were at variance with the muscularis blood flow but were clearly correlated to the calculated mucosal-submucosal blood flow. The uneven blood flow distribution in the intestinal wall did not affect the ability of the flowmeters to reflect total blood flow from either side of the bowel wall. A calibration curve could be constructed for approximate interpretation of the laser Doppler signals in absolute flow units. However, further experiments in humans and further development of the technique must be performed to elucidate clinical applications of the method.
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Wilson JR, Singh A, Craven C, Verrier MC, Drew B, Ahn H, Ford M, Fehlings MG. Early versus late surgery for traumatic spinal cord injury: the results of a prospective Canadian cohort study. Spinal Cord 2012; 50:840-3. [DOI: 10.1038/sc.2012.59] [Citation(s) in RCA: 138] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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138 |
7
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John ER, Prichep L, Ahn H, Easton P, Fridman J, Kaye H. Neurometric evaluation of cognitive dysfunctions and neurological disorders in children. Prog Neurobiol 1983; 21:239-90. [PMID: 6665163 DOI: 10.1016/0301-0082(83)90014-x] [Citation(s) in RCA: 130] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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42 |
130 |
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Ahn H, Prichep L, John ER, Baird H, Trepetin M, Kaye H. Developmental equations reflect brain dysfunctions. Science 1980; 210:1259-62. [PMID: 7434027 DOI: 10.1126/science.7434027] [Citation(s) in RCA: 120] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Developmental equations, which predict 32 parameters of the electroencephalogram recorded from the healthy human as a function of age, were tested in diverse groups of children. Few significant deviations were found in normal children, even in a culture different from the one on which the equations were based. A high incidence of significant deviations was found in children with learning disabilities and those at risk for various neurological disorders.
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120 |
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Kim JH, Kim HY, Kim NY, Kim SW, Kim JG, Kim JJ, Roe IH, Seo JK, Sim JG, Ahn H, Yoon BC, Lee SW, Lee YC, Chung IS, Jung HY, Hong WS, Choi KW. Seroepidemiological study of Helicobacter pylori infection in asymptomatic people in South Korea. J Gastroenterol Hepatol 2001; 16:969-75. [PMID: 11595059 DOI: 10.1046/j.1440-1746.2001.02568.x] [Citation(s) in RCA: 109] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
BACKGROUND Helicobacter pylori infection occurs throughout the world and causes gastroduodenal diseases in all age groups. The prevalence of H. pylori infection varies between countries and races. The aim of this study was to evaluate the seroprevalence of H. pylori infection in asymptomatic healthy people in South Korea. METHODS From March 1998 to October 1998, 5732 asymptomatic subjects who responded to the self-assessment questionnaires from 54 hospitals in South Korea were enrolled in this study. The serum levels of antibodies for H. pylori immunoglobulinG were measured by using an ELISA test. RESULTS The overall seroprevalence of H. pylori infection was 46.6% and there was no statistical difference between males (47.2%) and females (45.9%). In adults, a significant difference was observed between genders. According to the geographic areas, the high prevalent provinces were Kangwon (53.4%), Cheju (52.9%) and Cholla province (50.6%); Seoul (41.9%) was the lowest prevalent area. The seroprevalence increased with age and was highest when patients were aged in their 40s (78.5%). The characteristic feature of our study was that the infection rate was steeply increased in three age groups (10-12 year olds, 16-19 year olds and those aged in their 20s). In Seoul, there was no difference in the prevalence rate among the districts studied. CONCLUSIONS This nation-wide seroprevalence of H. pylori infection in South Korea was 46.6%, which showed the transition from a developing country to a developed country. More studies on the epidemiological factors and the route of transmission of H. pylori infection should be warranted.
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Review |
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109 |
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Ahn H, Bronge A, Johansson K, Ygge H, Lindhagen J. Effect of continuous postoperative epidural analgesia on intestinal motility. Br J Surg 1988; 75:1176-8. [PMID: 3233467 DOI: 10.1002/bjs.1800751210] [Citation(s) in RCA: 85] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The effect of postoperative epidural bupivacaine on intestinal motility was studied by measuring the transit time of barium contrast through the intestines in 16 patients after resection of the left colon and/or rectum. Fourteen patients served as controls and received postoperative injections of pentazocine. Mean transit time through the intestinal tract was 35 h in the epidural group and 150 h in the control group, a difference that is significant at the 0.1 per cent level. The average time before passage of flatus and faeces was different between the two groups at the 0.1 per cent level. We conclude that postoperative epidural bupivacaine constitutes an effective means of analgesia after colorectal surgery and is associated with a short duration of intestinal paralysis.
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Comparative Study |
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85 |
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Lee JL, Kim MK, Park I, Ahn JH, Lee DH, Ryoo HM, Song C, Hong B, Hong JH, Ahn H. RandomizEd phase II trial of Sunitinib four weeks on and two weeks off versus Two weeks on and One week off in metastatic clear-cell type REnal cell carcinoma: RESTORE trial. Ann Oncol 2015; 26:2300-5. [PMID: 26347107 DOI: 10.1093/annonc/mdv357] [Citation(s) in RCA: 83] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2015] [Accepted: 08/19/2015] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND The standard sunitinib schedule, 4 weeks on, followed by 2 weeks off (4/2 schedule), is associated with troublesome toxicities, and maintenance of adequate sunitinib dosing and drug levels, which are essential for achieving an optimal treatment outcome, is challenging. The objective of this study was to investigate the efficacy and safety of an alternative sunitinib dosing schedule of 2 weeks on and 1 week off (2/1 schedule) compared with the standard sunitinib schedule of 4 weeks on and 2 weeks off (4/2 schedule). PATIENTS AND METHODS In this multicenter, randomized, open-label, phase II trial, treatment-naïve patients with clear-cell type metastatic renal cell carcinoma (mRCC) were randomly assigned to 4/2 or 2/1 schedules after stratification by Memorial Sloan Kettering Cancer Center risk group and the presence or absence of measurable lesions. The primary end point was the 6-month failure-free survival (FFS) rate, determined by intention-to-treat analysis. RESULTS From November 2007 to February 2014, 76 patients were accrued, and 74 were eligible. FFS rates at 6 months were 44% with the 4/2 schedule (N = 36) and 63% with the 2/1 schedule (N = 38). Neutropenia (all grades, 61% versus 37%; grade 3-4, 28% versus 11%) and fatigue (all grades, 83% versus 58%) were more frequently observed with schedule 4/2. There was a strong tendency toward a lower incidence of stomatitis, hand-foot syndrome, and rash with schedule 2/1. Objective response rates (ORRs) were 47% in schedule 2/1 and 36% in schedule 4/2. With a median follow-up of 30.0 months, the median time to progression (TTP) was 12.1 months in schedule 2/1 and 10.1 months in schedule 4/2. CONCLUSION Sunitinib administered with a 2/1 schedule is associated with less toxicity and higher FFS at 6 months than a 4/2 schedule, without compromising the efficacy in terms of ORR and TTP (NCT00570882).
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Research Support, Non-U.S. Gov't |
10 |
83 |
12
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Abstract
The present study was conducted to isolate and to characterize stromal cells from the human prostate and to study the effects of androgen and different growth factors in this model system. Benign prostatic hyperplasia (BPH) tissue samples were obtained from transurethral resection of the prostate (TURP). Tissue specimens were mechanically and enzymatically dissociated by treatment with DNAse and collagenase. Epithelial cells were separated from stromal cells by discontinuous Percoll gradient centrifugation. The stromal cells obtained were cultured in phenol red-free RPMI-1640 supplemented with 10% fetal bovine serum. Immunocytochemical analysis revealed that the stromal cell cultures were composed of both smooth muscle cells and fibroblasts. The short and broad, smooth muscle cells wee identified by using an antibody directed against alpha-smooth muscle actin. The thin and elongated fibroblasts stained positively for prolyl 4-hydroxylase. Smooth muscle cells were the predominant cell type in the present investigation. Typical cultures contained up to 99% of cells staining positively for alpha-smooth muscle actin. The prostate smooth muscle cultures were treated with dihydrotestosterone (DHT), bovine pituitary extract (BPE), basic fibroblast growth factor (bFGF) and transforming growth factor-beta (TGF-beta). When cells were cultured in serum free RPMI-1640 supplemented with ITS+ (insulin, transferrin, and selenious acid) no significant (P > 0.05) mitogenic effect in medium supplemented with ITS+. In the presence of 10% charcoal-stripped fetal bovine serum (cFBS) DHT, at a concentration of 0.1 nM, was able to cause a slight but significant (P < 0.05) mitogenic effect on BPH smooth muscle cells growth. Basic FGF was able to stimulate BPH smooth muscle cells in a concentration-dependent fashion. The combination of DHT and 0.1 ng/ml bFGF was able to increase the proliferation of prostate smooth muscle cells above either agents alone. Addition of BPE to serum free RPMI-1640 caused a significant (P < 0.05) stimulation of cell proliferation in a concentration-dependent fashion. Addition to TGF-beta to serum or BPE containing RPMI-1640 caused a significant (P < 0.05) inhibition to cell proliferation in a concentration-dependent fashion. TGF-beta was cytostatic to the benign prostatic smooth muscle cells only in the presence of media containing growth stimulating factors found in charcoal-stripped serum or in bovine pituitary extract. These results demonstrated that stromal fraction isolated from BPH specimens was composed of both fibroblasts and smooth muscle cells. These cells could be cultured and were able to respond to various growth stimulatory and inhibitory agents.
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Lee JL, Ahn JH, Lim HY, Park SH, Lee SH, Kim TM, Lee DH, Cho YM, Song C, Hong JH, Kim CS, Ahn H. Multicenter phase II study of sunitinib in patients with non-clear cell renal cell carcinoma. Ann Oncol 2012; 23:2108-2114. [PMID: 22228449 DOI: 10.1093/annonc/mdr586] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/06/2023] Open
Abstract
BACKGROUND Retrospective and molecular biologic data suggest that sunitinib may be effective in patients with non-clear cell renal cell carcinoma (nccRCC). PATIENTS AND METHODS Eligibility criteria included advanced nccRCC except for collecting duct carcinoma and sarcomatoid carcinoma without identifiable renal cell carcinoma subtypes. Patients were treated with 50 mg/day oral sunitinib for 4 weeks, followed by 2 weeks of rest. The primary end point was overall response rate (RR). RESULTS Thirty-one eligible patients were enrolled. Twenty-four patients (77%) had prior nephrectomy. By Memorial Sloan-Kettering Cancer Center criteria, 8 patients (26%) had poor risk and 14 (45%) had intermediate risk. Twenty-two patients had papillary renal cell carcinoma (RCC), and three had chromophobe RCC. Eleven patients had partial response with a RR of 36% (95% confidence interval (CI) 19% to 52%) and an additional 17 patients (55%) had stable disease. Median duration of response was 12.7 months (95% CI 6.3-19.1 months), and median progression-free survival was 6.4 months (95% CI 4.2-8.6 months). At a median follow-up duration of 18.7 months (95% CI 13.7-23.7 months), 13 patients (42%) had died, resulting in an estimated median survival of 25.6 months (95% CI 8.4-42.9 months). Toxicity profiles were commensurate with prior reports. CONCLUSIONS Sunitinib has promising activity in patients with nccRCC (NCT01219751).
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Clinical Trial, Phase II |
13 |
74 |
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Reitze DH, Ahn H, Downer MC. Optical properties of liquid carbon measured by femtosecond spectroscopy. PHYSICAL REVIEW. B, CONDENSED MATTER 1992; 45:2677-2693. [PMID: 10001814 DOI: 10.1103/physrevb.45.2677] [Citation(s) in RCA: 64] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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33 |
64 |
15
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Sachinidis A, Seul C, Seewald S, Ahn H, Ko Y, Vetter H. Green tea compounds inhibit tyrosine phosphorylation of PDGF beta-receptor and transformation of A172 human glioblastoma. FEBS Lett 2000; 471:51-5. [PMID: 10760511 DOI: 10.1016/s0014-5793(00)01360-0] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The effect of the green tea compounds 2-(3,4-dihydroxyphenyl)-3, 4-dihydro-2H-1-benzopyran-3,5,7-triol (catechin), epicathechin (EC), epigallocathechin-3 gallate (EGCG), epicathechin-3 gallate (ECG) and catechin-3 gallate (CG) on the tyrosine phosphorylation of PDGF beta-receptor (PDGF-Rbeta) and on the anchorage-independent growth of A172 glioblastoma cells in semisolid agar has been investigated. Treatment of A172 glioblastoma with 50 microM CG, ECG, EGCG and 25 microM Tyrphostin 1296 resulted in an 82+/-17%, 77+/-21%, 75+/-8% and 55+/-11%, respectively (mean+/-S.D., n=3) inhibition of the PDGF-BB-induced tyrosine phosphorylation of PDGF-Rbeta. The PDGF-Rbeta downstream intracellular transduction pathway including tyrosine phosphorylation of phospholipase C-gamma1 (PLC-gamma1) and phosphatidylinositol 3'-kinase (PI 3'-K) was also inhibited. Spheroid formation was completely inhibited by 50 microM ECG, CG, EGCG and by 25 microM Tyrphostin 1296. We conclude that catechins of the green tea possessing the gallate group in their chemical structure act as anticancer agents probably partly via their ability to suppress the tyrosine kinase activity of the PDGF-Rbeta.
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Ahn H, Johansson K, Lundgren O, Nilsson GE. In vivo evaluation of signal processors for laser Doppler tissue flowmeters. Med Biol Eng Comput 1987; 25:207-11. [PMID: 2961959 DOI: 10.1007/bf02442852] [Citation(s) in RCA: 62] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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Johansson K, Ahn H, Lindhagen J, Lundgren O. Tissue penetration and measuring depth of laser Doppler flowmetry in the gastrointestinal application. Scand J Gastroenterol 1987; 22:1081-8. [PMID: 2962271 DOI: 10.3109/00365528708991962] [Citation(s) in RCA: 60] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Tissue penetration of laser light and measuring depth (depth sensitivity) for laser Doppler flowmetry in the gastrointestinal application were studied in the feline and human bowel and stomach with a wall thickness of from 2.1 to 7.0 mm. Mucosal and serosal recordings from corresponding sites in the gastrointestinal tract were comparable and in the intestine correlated to total blood flow. Laser light was reflected by a mirror placed on the opposite side of the bowel wall, and hyperemic reactions were similarly recorded from both sides of the bowel with wall thickness up to 6 mm. Placing layers of unperfused feline small intestine (average thickness, 2.1 mm) between the probe and the perfused feline gastric wall attenuated the laser Doppler signal in an exponential manner. We conclude that with this instrument, the tissue penetration and measuring depth of laser Doppler flowmetry are at least 6 mm in the gastrointestinal application.
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60 |
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Johansson K, Ahn H, Lindhagen J, Tryselius U. Effect of epidural anaesthesia on intestinal blood flow. Br J Surg 1988; 75:73-6. [PMID: 2962690 DOI: 10.1002/bjs.1800750127] [Citation(s) in RCA: 59] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The effect of epidural bupivacaine (5 mg/ml) on intestinal blood flow was studied with laser Doppler flowmetry in 15 patients during operations including various types of large bowel resection. In the colon, blood flow increased in 13 out of 15 patients, which was significant at the 1 per cent level. The average increase was 41 per cent. In the ileum an increase was found in eight out of eleven patients who could be studied, which was significant at the 5 per cent level. Bowel function was restored satisfactorily in all patients. It is concluded that epidural bupivacaine has a favourable effect on intestinal blood flow during colorectal surgery.
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37 |
59 |
19
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Ku YH, Han KA, Ahn H, Kwon H, Koo BK, Kim HC, Min KW. Resistance Exercise Did Not Alter Intramuscular Adipose Tissue but Reduced Retinol-binding Protein-4 Concentration in Individuals with Type 2 Diabetes Mellitus. J Int Med Res 2010; 38:782-91. [PMID: 20819415 DOI: 10.1177/147323001003800305] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Lipid accumulation in muscle is associated with diminished insulin sensitivity. It was hypothesized that resistance exercise decreases muscular adipose tissue and reduces the level of retinol-binding protein-4 (RBP4), which is linked to adipose tissue and insulin sensitivity in diabetics. Forty-four women with type 2 diabetes were randomly assigned to three groups for a period of 12 weeks: control (asked to maintain a sedentary lifestyle); resistance exercise (elastic band exercise at moderate intensity five times per week); and aerobic exercise (walking for 60 min at moderate intensity five times per week). Subcutaneous (SCAT), subfascial (SFAT) and intramuscular (IMAT) adipose tissues at mid-thigh level were assessed using computed tomography, and RBP4 level and insulin sensitivity (fractional disappearance rate of insulin, kITT) were assessed before and after intervention. Changes in SCAT, SFAT, IMAT, RBP4 and kITT were similar among the three groups. Within-group analysis revealed that body mass index and waist circumference decreased significantly in both exercise groups, but RBP4 decreased significantly only with resistance exercise. Resistance exercise did not alter muscular adipose tissue or improve insulin sensitivity.
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15 |
58 |
20
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Seibert K, Cho GC, Kütt W, Kurz H, Reitze DH, Dadap JI, Ahn H, Downer MC, Malvezzi AM. Femtosecond carrier dynamics in graphite. PHYSICAL REVIEW. B, CONDENSED MATTER 1990; 42:2842-2851. [PMID: 9995773 DOI: 10.1103/physrevb.42.2842] [Citation(s) in RCA: 58] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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35 |
58 |
21
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Ahn H, Lindhagen J, Nilsson GE, Oberg PA, Lundgren O. Assessment of blood flow in the small intestine with laser Doppler flowmetry. Scand J Gastroenterol 1986; 21:863-70. [PMID: 2946070 DOI: 10.3109/00365528609011131] [Citation(s) in RCA: 57] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Blood flow in the small intestine was assessed in 48 patients by laser Doppler flowmetry. Mucosal and serosal flowmeter signals were compared during 'resting' conditions, vascular occlusion, and reactive hyperemia. Serosal flowmeter recordings were compared with the total blood flow of a bowel segment as measured by venous collection. The magnitudes of the mucosal (n = 49) and serosal (n = 49) flowmeter signals were comparable throughout the whole range of flowmeter signals (r = 0.97; p less than 0.001). A correlation coefficient of 0.95 (n = 51; p less than 0.001) was obtained between serosal flowmeter signals and total blood flow during 'resting' and reduced blood flows. During vasodilatation after a vascular occlusion, blood flow was underestimated by the flowmeter. A calibration curve could be constructed for approximate interpretation of the flowmeter signals in absolute flow units. The present study underlines the potential of laser Doppler flowmetry in the assessment of blood flow in the human small intestine.
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39 |
57 |
22
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Biancone L, Andres G, Ahn H, Lim A, Dai C, Noelle R, Yagita H, De Martino C, Stamenkovic I. Distinct regulatory roles of lymphocyte costimulatory pathways on T helper type-2 mediated autoimmune disease. J Exp Med 1996; 183:1473-81. [PMID: 8666905 PMCID: PMC2192532 DOI: 10.1084/jem.183.4.1473] [Citation(s) in RCA: 55] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
We assessed the role of CD40-CD40L, cytotoxic T lymphocyte (CTL)A4/CD28-B7s, and CD2-CD48/CD58 lymphocyte costimulatory pathways in the development of mercury chloride (HgCl2)-induced autoimmune disease in mice, which is believed to be mediated by T helper (Th) subset Th2. Inhibition of CD40-CD40-L and CTLA4/CD28-B7s interactions by anti-CD40-L antibody and soluble CTLA4-immunoglobulin (Ig) fusion protein, respectively, abrogated the autoimmune disease without affecting interleukin 4 (IL-4) production, showing the importance of physical contact between T and B lymphocytes in the Th2-mediated process. In contrast, two anti-CD2 antibodies that have been shown to induce immunosuppression of Th1-mediated events exacerbated the autoantibody response and augmented IgG1, IgE, and IL-4 production, transforming a mild mesangial glomerulopathy into a severe systemic immune complex disease. These observations demonstrate that manipulation of lymphocyte accessory counterreceptor interactions may affect the course of Th2-associated autoimmune disease and suggest that signals resulting from CD2 engagement play an essential role in the regulation of the Th1-Th2 effector equilibrium.
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research-article |
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55 |
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Abstract
Computed tomographic (CT) angiography is a new minimally invasive vascular imaging modality. FOr its clinical use to increase, the advantages and potential applications of this modality must be understood. The clinical applications of CT angiography in the thoracic aorta and its branches include evaluation of congenital aortic anomalies, aortic aneurysm, aortic dissection, Takayasu arteritis, penetrating aortic atherosclerotic ulcer, traumatic aortic injury, the postoperative aorta, arch vessels, and pulmonary sequestration. The advantages of CT angiography over conventional angiography are as follows: (a) high-quality, thin axial sections that demonstrate mural changes, extraluminal pathologic conditions, and spatial relationships with adjacent organs; (b) high contrast resolution and high sensitivity for detecting calcified lesions; (c) angiographic or three-dimensional display of vascular structures and adjacent organs in any projection with a single spiral acquisition; and (d) demonstration of extrinsic causes of vascular compromise. CT angiography has the potential to replace conventional catheter angiography in the diagnosis of many pathologic conditions of the thoracic aorta.
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Kim KB, Lim C, Ahn H, Yang JK. Intraaortic balloon pump therapy facilitates posterior vessel off-pump coronary artery bypass grafting in high-risk patients. Ann Thorac Surg 2001; 71:1964-8. [PMID: 11426775 DOI: 10.1016/s0003-4975(01)02638-8] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
BACKGROUND Displacement of the heart to expose posterior vessels during coronary artery bypass grafting (CABG) without cardiopulmonary bypass (off-pump CABG, or OPCAB) may impair cardiac function. We used the intraaortic balloon pump (IABP) preoperatively to reduce operative risk and to facilitate posterior vessel OPCAB in high-risk patients with left main coronary artery disease (> 75% stenosis), intractable resting angina, postinfarction angina, left ventricular dysfunction (ejection fraction < 35%), or unstable angina. METHODS One hundred and forty-two consecutive patients who underwent multivessel OPCAB including posterior vessel revascularization were studied prospectively. The patients were divided into group I (n = 57), which received preoperative or intraoperative IABP, and group II (n = 85), which did not receive IABP. In group I, there were 34 patients with left main coronary artery disease, 24 patients with intractable resting angina, 8 patients with left ventricular dysfunction, 5 patients with postinfarction angina, and 40 patients with unstable angina. Seven patients received intraoperative IABP support owing to hemodynamic instability during OPCAB. RESULTS There was no operative mortality in group I and 1 death in group II. The average number of distal anastomoses was not different between group I and group II (3.4 +/- 0.9 versus 3.5 +/- 0.9, p = not significant). There were no significant differences in the number of posterior vessel anastomoses per patient. There were no differences in ventilator support time, length of stay in the intensive care unit, hospital stay, and morbidity between the two groups. There was one IABP-related complication in group I. CONCLUSIONS IABP therapy facilitates posterior vessel OPCAB in high-risk patients, and surgical results are comparable with those in lower-risk patients.
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Park SK, Yang WS, Lee SK, Ahn H, Park JS, Hwang O, Lee JD. TGF-beta(1) down-regulates inflammatory cytokine-induced VCAM-1 expression in cultured human glomerular endothelial cells. Nephrol Dial Transplant 2000; 15:596-604. [PMID: 10809798 DOI: 10.1093/ndt/15.5.596] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Endothelial cells are active participants in the processes controlling coagulation, inflammation and the immune response. Variations are recognized between endothelia isolated from different vascular beds as well as from different species. Though transforming growth factor-beta(1) (TGF-beta(1)) has been known to have an anti-inflammatory action, little is known about its effect on expression of cellular adhesion molecules during the inflammatory process in human glomerular endothelial cells. The aim of this study was to determine the effect of TGF-beta(1) on the inflammatory cytokine-induced expression of vascular cell adhesion molecule-1 (VCAM-1) in cultured human glomerular endothelial cells. METHODS The culture of human glomerular endothelial cells was established using the normal portion of nephrectomized renal tissues and identified by factor VIII staining and cellular uptake of fluorescent-labelled acetylated low-density lipoprotein (LDL). The endothelial cells were stimulated by interleukin-1beta (IL-1beta), tumour necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma) with or without TGF-beta(1). Cellular expression of VCAM-1 was measured by enzyme-linked immunosorbent assay (ELISA) and flow cytometry, and VCAM-1 mRNA was measured by Northern blot analysis. RESULTS TGF-beta(1) (1, 10 and 25 ng/ml) blunted IL-1beta- (5 ng/ml) induced VCAM-1 expression significantly (OD=1.08+/-0.14, 1. 10+/-1.16 and 1.05+/-0.14 vs IL-1beta=1.97+/-0.29, n=6, P<0.05) in ELISA. The addition of TGF-beta(1) (1, 10 and 25 ng/ml) also suppressed TNF-alpha- (10 ng/ml) induced VCAM-1 expression (OD=1. 14+/-0.15, 1.17+/-0.17 and 1.18+/-0.16 vs TNF-alpha=1.96+/-0.26, n=6, P<0.05). The same results were obtained by flow cytometry. TGF-beta(1) (10 ng/ml) inhibited both IL-1beta- (5 ng/ml) and TNF-alpha-(10 ng/ml) induced expression of VCAM-1 (MFI: IL-1beta=90. 8+/- 17.6, IL-1beta+TGF-beta(1)=37.8+/-14.9, TNF-alpha=113.6+/- 12.4, TNF-alpha+TGF-beta(1)=64.3+/-13.8, mean+/-SD, n=3, P<0.05). By Northern blot analysis, TGF-beta(1) (10 ng/ml) significantly suppressed the stimulatory effect of IL-1beta and TNF-alpha. CONCLUSIONS These results show that TGF-beta(1) down-regulates the inflammatory cytokine-induced expression of VCAM-1 in human glomerular endothelial cells, which could be a novel mechanism for the anti-inflammatory action of TGF-beta(1) during the inflammatory processes in human glomerular diseases.
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