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Biomedical subjects

Y Seo

Publications and source records attributed to Y Seo.

At least 19 recordsLinked to original sources
PubMed1999

A sandwich enzyme immunoassay for human muscle-specific beta-enolase and its application for the determination of skeletal muscle injury.

A sensitive sandwich enzyme immunoassay for human beta-enolase was developed and used to examine beta-enolase in blood or bloodstains as a marker for the determination of skeletal muscle injury. Human beta-enolase was purified from human skeletal muscle, and then an antibody against it was prepared. Polystyrene balls coated with rabbit anti-human beta-enolase IgG were incubated with human beta-enolase and then with anti-human beta-enolase Fab'-peroxidase conjugate. Peroxidase activity bound to the polystyrene balls was assayed by fluorometry using 3-(4-hydroxyphenyl)propionic acid as a hydrogen donor. The detection limit for human beta-enolase was 2.6 pg (30 amol) per assay. The degree of cross-reaction of the sandwich enzyme immunoassay for other organs except for heart (1/10) was about 1/150 or less. Moreover, the localization of beta-enolase in various human tissues was examined by Northern blot analysis, and this confirmed that beta-enolase was expressed only in skeletal and cardiac muscle. Antigenic activity in bloodstains containing beta-enolase was recovered well after storage for 60 days at room temperature. The ratio of beta-enolase to total protein in bloodstains made from non-traumatic blood, nasal hemorrhage and menstrual blood, was within the normal range. In contrast, the ratio of beta-enolase in bloodstains from traumatic blood was obviously elevated (10-30 fold) in comparison with non-traumatic blood. Furthermore, the ratio of beta-enolase was proved to be higher in stains adhering to weapons that had passed through skeletal muscle, indicating that detection of beta-enolase in bloodstains could be used to distinguish crime weapons. These results suggest that beta-enolase is a useful marker for identification of skeletal muscle injury as well as for detecting the origin of bleeding.

Animals↗
PubMed1999

Intestinal energy metabolism during ischemia and reperfusion.

BACKGROUND: In order to evaluate acute ischemic damage in the small intestine induced by superior mesenteric artery occlusion (SMAO) and subsequent reperfusion, changes in ATP, ADP, and AMP were measured by high-performance liquid chromatography, and changes in tissue blood flow were measured (from the serosal surface) by the laser doppler flow meter in a rat model. MATERIALS AND METHODS: The superior mesenteric artery of the rat was occluded for 30, 60, 90, and 120 min and then reopened. Core temperature was maintained carefully at 37 +/- 0.3 degrees C. RESULTS: All rats that underwent 90 and 120 min of SMAO died within 2 days, but those with 30 and 60 min of SMAO survived. ATP (10.39 +/- 0.90 micromol/g dry weight), ADP (3.34 +/- 0.33), and total adenine nucleotides (TAN; 14.08 +/- 0. 86) decreased with longer SMAO times. After 30 and 60 min of SMAO followed by reperfusion, recoveries of ATP and TAN were relatively good and ADP levels remained fairly steady, but little or no recovery of these levels was observed after 90 and 120 min of SMAO followed by reperfusion. There were linear correlations between the levels of ATP and TAN after 30 min of reperfusion and the time of SMAO. Tissue blood flow levels were constant during SMAO. After reperfusion, those levels were recovered along with the SMAO periods. But recovery rates compared with control values were not related with those of ATP. CONCLUSIONs. ATP and TAN levels, particularly at 30 min after reperfusion, seemed to be in good agreement with the tissue damage and the viability of the small intestine. We propose that the measurement of these levels may be useful for the evaluation of intestinal damage and viability.

Adenosine Diphosphate↗
PubMed1999

New acetylenic enol ethers of glycerol from the sponge Petrosia sp.

Ten acetylenic enol ethers of glycerols, including six new compounds (1-6) and a linear acetylenic alcohol (7), have been isolated from a sponge of the genus Petrosia. The structures of the novel compounds were elucidated by spectroscopic methods. The absolute stereochemistry of 1-7 was determined by chemical transformations and the Mosher method. Some of these compounds exhibited weak cytotoxicity against a human leukemia cell-line (K-562).

Acetylene↗
PubMed1999

New Bis(Indole) alkaloids of the topsentin class from the sponge spongosorites genitrix

Four bis(indole) alkaloids of the topsentin class, including two new brominated compounds (1 and 2), have been isolated from the sponge Spongosorites genitrix collected from Jaeju Island, Korea. The structures of the novel compounds were determined by spectroscopic methods. These compounds exhibited moderate cytotoxicity against a human leukemia cell-line (K-562).

Journal Article↗
PubMed1999

Improvement of molar ratio of branched-chain amino acids to tyrosine (BTR) associated with liver fibrosis in chronic hepatitis C patients treated with interferon-alpha.

The molar ratio of branched-chain amino acids (BCAA) to tyrosine (BTR), which has recently been possible to easily determine by an enzymatic method, can be clinically used as a substitute for that of BCAA to aromatic amino acids (AAA). We used this method to investigate the diagnostic implications of serum BTR in patients with chronic hepatitis C treated with interferon-alpha. There was a good correlation between BTR and staging (fibrosis) scores both before and after treatment. BTR increased significantly at 24 months after treatment in the responder group (P < 0.01). Moreover, a significant increase in BTR was observed in patients with improved staging (P = 0.015), but not grading (necroinflammatory), scores. BTR in chronic hepatitis C patients seems to be reflected by the extent of liver fibrosis, and, in the responder group, it can be improved, together with liver fibrosis, by interferon-alpha treatment.

Adult↗
PubMed1998

Outcomes of stent-graft treatment of false lumen in aortic dissection.

BACKGROUND: Stent-graft treatment for aortic disease promises to lead to a less invasive therapy than conventional surgical therapy. However, this treatment has not been established as a therapy for aortic dissection. The aim of this study was to examine the effect of stent-graft treatment of aortic dissection, as measured by follow-up data on entry site closure, clotting in the false lumen, and the outcome of the false lumen from the acute to chronic phase after operation. METHODS AND RESULTS: We used a stent-graft of our own design to close the entry site of aortic dissection in 21 cases: 9 were acute (< 14 days), 8 subacute (< 6 months), and 4 chronic (> 6 months). Nine were type A and 12 were type B. In 15 cases, the stent-graft was inserted through the transverse arch, which had been surgically opened under median sternotomy. In the other 6 cases, the stent-graft was inserted by means of a transcatheter through a femoral artery. Using computed tomographic scans, we followed and examined clot formation in the false lumen and reduction in size of the false lumen at 3 levels: at the level of maximum aortic diameter, at the distal end of the stent-graft, and 50 mm distal to the stent-graft. The entry sites were successfully closed in 19 cases (90.4%); in the remaining 2 (both treated with a transcatheter) there was perigraft leakage into the false lumen. The hospital mortality rate of these stent-graft treatments was 14.3% (3 of 21). At 2 weeks after operation, the false lumen had completely clotted, respectively, in 100%, 77%, and 38% of cases at the 3 measurement levels. Substantial shrinkage (> 50% in diameter) of the false lumen at 6 months after the operation was observed in 72%, 60%, and 38% of cases at the respective levels. Shrinkage of the false lumen was particularly enhanced in patients treated within 6 months from the onset of dissection: The false lumen shrank by > 50% in 93%, 75%, and 50% of patients. CONCLUSIONS: In cases of aortic dissection, the stent-graft is an effective tool for closing the entry site and promoting clot formation in the false lumen and for reducing the size of the false lumen within 6 months of the onset of dissection if the entry site has been closed.

Adult↗
PubMed1998

Sequence polymorphism of mitochondrial DNA control region in Japanese.

Sequence polymorphisms of the mitochondrial DNA (mtDNA) control region, hypervariable regions I and II, from 100 unrelated Japanese were determined by PCR amplification and direct sequencing. Sequences of 404 nucleotides for hypervariable region I and 379 nucleotides for region II were obtained. Variable sites (85 and 45) were revealed in region I and region II, respectively, as compared to the reference sequence, and a total of 96 different genetic patterns from both regions I and II were determined. A point mutation heteroplasmy was observed at the ratio of approximately 50:50 from one individual at the sequence position 151 showing a nucleotide transition from C to T. The probability of identity was estimated as 2.3% for region I, 3.9% for region II, and 1.1% combined for both regions. These results suggest that sequence polymorphism of mtDNA control region would be very useful in forensic practice as a marker for individual identification.

Base Sequence↗
PubMed1998

Tandem repeat structure of the duplicated Y-chromosomal STR locus DYS385 and frequency studies in the German and three Asian populations.

The Y-chromosomal short tandem repeat (STR) locus DYS385 can be typed using PCR amplification and separation of the resulting polymorphic fragments by non-denaturing high resolution polyacrylamide gel electrophoresis followed by silver staining. The PCR primers amplify a duplicated repeat sequence on the Y chromosome revealing a two-band pattern in male individuals. To determine the internal repeat structure as a basis for a consensus nomenclature, DNA sequence analysis was carried out after subcloning of PCR-amplified fragments revealing the uniform 4-bp repeat structure 'GAAA'. The shortest allele observed consisted of 10 repeat units thus providing the basis for the designation 'allele 10'. Except for isolated point mutations, no systematic differences could be observed either in the repeat sequence or in the flanking regions between the two fragments of a given individual. Thus it was not possible to discriminate between the two loci of the DYS385 system. Four population samples of German (n = 146), Chinese (n = 100), Japanese (n = 100), and Thai (n = 95) origin were studied. In the four groups, alleles 10 to 24 could be observed and genotype frequencies differed significantly. In Germans only one common genotype was present (11-14; 33.8% frequency). In the Asian populations, the frequencies were more evenly distributed with the 13-13 genotype (9%) in Chinese, the 13-17 genotype (14%) in Japanese and the 14-18 genotype (7%) in Thai being the most common. Overall, 69 different genotypes were found, of these 36 were observed in Germans, 36 in Chinese, 33 in Japanese and 44 in Thai. No mutations were detected in 62 father-son pairs. Thus DYS385 is a highly polymorphic STR system with population-specific genotype distributions.

Asia, Southeastern↗
PubMed1998

Magnetic resonance imaging of experimental subacute spinal cord compression.

STUDY DESIGN: Subacute compression of the spinal cord was applied to rats. The animals were chronologically observed using magnetic resonance imaging for more than 8 weeks after surgery and were killed for histopathologic examination. OBJECTIVES: To investigate the correlation of changes in signal intensity on magnetic resonance images with those observed in histopathologic study and with the degree of spinal cord compression and paralysis. SUMMARY OF BACKGROUND DATA: No consensus has been reached concerning the correlation of magnetic resonance images to clinical symptoms of compressive myelopathy. Few reports are available in which magnetic resonance imaging findings are compared with histopathologic features in chronic or subacute experiments. METHODS: In rats under general anesthesia, the T11 lamina was thinned and a slow increase in volume was applied. Hind limb paralysis appeared 1 week after the procedure and spontaneously subsided thereafter. The degree of spinal compression and signal intensity was observed chronologically using magnetic resonance imaging. The signal intensity on the final MR images was rated on a four-point scale and compared with histopathologic findings. RESULTS: As spinal compression increased, the incidence of high signal intensity on long spin-echo images became higher. Low signal intensities on short spin-echo images were visible in animals in which compression and paralysis were the most severe. In these animals, cavitation and a dilated central canal were visible. High signal intensities on long spin-echo images reflected various pathologic changes. CONCLUSIONS: Changes in signal intensity on MR images are visible after the induction of myelopathy by high-pressure compression. These signal intensities may be useful in predicting the outcome of compressive myelopathy.

Animals↗
PubMed1998

Mapping strain exerted on blood vessel walls using deuterium double-quantum-filtered MRI.

A technique is described for displaying distinct tissue layers of large blood vessel walls as well as measuring their mechanical strain. The technique is based on deuterium double-quantum-filtered (DQF) spectroscopic imaging. The effectiveness of the double-quantum filtration in suppressing the signal of bulk water is demonstrated on a phantom consisting of rat tail tendon fibers. Only intrafibrillar water is displayed, excluding all other signals of water molecules that reorient isotropically. One- and two-dimensional spectroscopic imaging of bovine aorta and coronary arteries show the characteristic DQF spectrum of each of the tissue layers. This property is used to obtain separate images of the outer layer, the tunica adventitia, or the intermediate layer, the tunica media, or both. To visualize the effect of elongation, the average residual quadrupole splitting is calculated for each pixel. Two-dimensional deuterium quadrupolar splitting images are obtained for a fully relaxed and a 55% elongated sample of bovine coronary artery. These images indicate that the strong effect of strain is associated with water molecules in the tunica adventitia whereas the DQF NMR signal of water in the tunica media is apparently strain-insensitive. After appropriate calibration, these average quadrupolar splitting images can be interpreted as strain maps.

Animals↗
PubMed1998

Submucosal gastric cancer with lymph node metastasis.

BACKGROUND AND OBJECTIVES: The intraoperative assessment of lymph node metastasis of gastric cancer remains difficult and the characteristics of recurrence after gastrectomy are not well known regarding submucosal cancer. METHODS: We examined 452 patients with submucosal gastric cancer and compared the clinicopathologic features as well as recurrence patterns between the 71 cases with lymph node metastasis (group I) and the 381 without it (group II). RESULTS: The mean tumor sizes were 44.8 and 33.5 mm, respectively (P < 0.01). The incidences of lymphatic invasion and vascular invasion were 91.5% (65/71) and 45.1% (32/71) in group I, which were significantly higher than those in group II (36.7 and 14.2%, 140/381 and 54/381, respectively, P < 0.01). A total of 21 patients (4.6%, 21/452) experienced recurrence after undergoing a gastrectomy and hematogenic recurrence was the most frequent type of recurrence (2.0%, 9/452). However, in group I, lymphatic recurrence was most frequently observed (7.0%, 5/71), and it was more frequent than in group II (0.3%, 1/381, P < 0.01). The median intervals between gastrectomy and recurrence were 34.5 and 64.0 months in groups I and II, respectively (P < 0.05). CONCLUSIONS: The submucosal cancer with larger size, lymphatic invasion, and vascular invasion has high risks for lymph node metastasis. Furthermore, a strict follow-up for lymphatic as well as hematogenic recurrence is important for the patients with node positive submucosal cancer, especially within 5 years after operation.

Female↗
PubMed1998

Proton double-quantum filtered MRI--a new method for imaging ordered tissues.

The imaging of connective tissues such as cartilage and tendons using standard MRI techniques is hampered by their low signal relative to the surrounding tissues. 1H double-quantum filtered (DQF) MRI is an imaging method that detects molecules associated with ordered structures, while the signal from isotropic fluids is filtered out, thus creating a new type of contrast. The technique is demonstrated on an intact rat tail, where the image of the tendons is highlighted. Although the signal-to-noise ratio is inferior to that in gradient-echo MRI, the contrast between the tendons and the surrounding tissues is significantly better in the DQF MRI. It is demonstrated how, by adjusting the parameters of the DQF imaging pulse sequence, one can modify the contrast and enhance the images of specific compartments within an organ. A comparison with 2H DQF imaging of the same tissue is also given.

Animals↗
PubMed1998

Selective detection of biexponential relaxation in isotropic solutions by mixed coherence filtering NMR.

This is a trial to simplize sequences to get the relaxation function f31(t), which is usually detected by the double- or triple-quantum filtered (DQF or TQF) NMR in an isotropic phase. The results indicate that only two phase cycling is needed to get the f31(t) function, which shows the advantage of S/N (signal-to-noise ratio) in a minimum acquisition time. The filtering of coherence levels in the creation time need not be limited to double- or triple-quantum coherences. An 87Rb signal from a 4% (w/w) agar powder in 500-mM RbCl solution is recorded at 130.9 MHz as a Larmor frequency using a Bruker MSL 400 spectrometer.

Chlorides↗
PubMed1998

[Transcatheter stent-graft implantation for the treatment of acute aortic dissection--rupture of aneurysm because of perigraft leakage].

An 82-year-old woman was diagnosed as having acute type B aortic dissection. At bed rest, her systolic blood pressure was kept less than 120 mmHg. Four days later the aneurysm threatened to rupture. Because she presented a high operative risk for open-chest surgery, a stent-graft was implanted across the dissection site via transcatheter. The entry site to the aneurysm was closed by the stent-graft, and postoperative aortograph demonstrated that contrast medium did not enter the false lumen except for a trivial projection. A CT scan 6 days after the stent-graft implantation unexpectedly demonstrated the false lumen not only had not thrombosed, but had expanded. As a result, 8 days after the operation the aneurysm ruptured into the left pleural cavity, and the patient died. An autopsy revealed the stent-graft was exactly implanted across the entry site, but that the diameter of the graft was slightly larger than that of the aorta. Consequently, a portion of the rim of the graft had been wraped after implantation, causing perigraft leakage. Leakage is one of the gravest complications of the stent-graft implantation, to prevent it, a new design for stent-graft device is essential.

Acute Disease↗
PubMed1998

Five new polyacetylenes from a sponge of the genus petrosia

Petrocortynes D-H, novel C46 polyacetylenes, were isolated from a sponge of the genus Petrosia collected from Keomun Island, Korea. Petrocortyne D (2) is a 4,5-dihydro derivative of a diastereomer of petrocortyne A (1), and petrocortynes E-H (3-6) possess an additional allylic-hydroxyl group. The structures of these compounds were determined by combined chemical and spectral methods, and absolute configurations of most of the asymmetric carbon centers were determined by the modified Mosher's method. Limitations on the application of Mosher's method to allylic alcohols is discussed. Petrocortynes D-H exhibited moderate cytotoxicity and inhibitory activity against PLA2.

Journal Article↗
PubMed1998

New secosteroids from a gorgonian of the genus Muricella.

Calicoferols F-I (2-5), four new 9,10-secosteroids, have been isolated from a gorgonian of the genus Muricella collected from Jaeju Island, Korea. The structures of these compounds have been determined by combined spectroscopic methods. Calicoferols exhibited significant cytotoxicity and inhibitory activity against PLA2.

Animals↗
PubMed1998

Clinical significance of serum hyaluronic acid as a fibrosis marker in chronic hepatitis C patients treated with interferon-alpha: histological evaluation by a modified histological activity index scoring system.

The aim of the present study was to investigate the histological changes effected by interferon (IFN) treatment and to evaluate the clinical significance of serum hyaluronic acid (HA) as a marker of fibrosis. Forty-nine patients with chronic hepatitis C treated with IFN-alpha were divided into three groups according to the existence of viraemia: sustained complete responders (CR), complete responders with relapse (PR) and non-responders (NR). Needle biopsy sections of the liver taken before and at the end of IFN treatment were assessed according to the modified histological activity index (HAI) scoring system. Serum fibrosis markers, including HA, were measured at needle biopsies. Biopsies of CR at the end of treatment showed a significant improvement in fibrosis and necroinflammatory scores. More significant correlation was observed between fibrosis scores and serum levels of HA before IFN treatment (r = 0.607, P < 0.0001) than those between fibrosis scores, on the one hand, and peptide of type III procollagen (PIIIP; r = 0.531, P = 0.0004) or type IV collagen 7S domain (type IV-C; r = 0.241, P = 0.1062) on the other. Moreover, serum HA levels fell significantly in patients in whom fibrosis improved (P = 0.011). This is the first paper describing the advantages of the modified HAI scoring system over others in estimating the effect of IFN-alpha; the results also indicate that serum HA can be useful in monitoring liver fibrosis in chronic hepatitis C patients treated with IFN-alpha.

Adult↗