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Biomedical subjects

Y Seo

Publications and source records attributed to Y Seo.

At least 37 records · Page 2Linked to original sources

Conservative treatment of hemolytic complication following coil embolization in two adult cases of patent ductus arteriosus.

Two adult cases of relatively large patent ductus arteriosus (PDA) were treated by coil embolization, but were complicated by hemolysis that was successfully managed by medical treatment. Case 1 was a 67-year-old woman and Case 2 was a 71-year-old woman with a PDA of minimal diameter of 5.3 mm and 5.5 mm, respectively. The approach was via the pulmonary artery and 2 coils were delivered simultaneously into the ductus, known as the 'kissing coil technique'. Although immediately after the procedure only a small residual shunt was revealed by aortogram, hemolysis occurred for several hours after the procedure in both cases. A hemolytic complication usually needs additional coil embolization or surgical treatment, but in these 2 cases it was successfully treated by haptoglobin infusion to prevent nephropathy and by antiplasmin infusion to promote thrombus formation. Hemolytic complications of coil embolization of PDA can managed by medication when the residual shunt is minimal and the degree of hemolysis is mild.

Aged↗

Effects of pCO(2) on the CSF turnover rate in T(1)-weighted magnetic resonance imaging.

The cerebrospinal fluid (CSF) secretion of rat was monitored by longitudinal relaxation time-weighted magnetic resonance imaging (T(1)-weighted MRI) in combination with a ventricular injection of a T(1)-relaxation reagent: gadolinium-diethylene triamine-N,N,N',N",N"-pentaacetic acid (Gd-DTPA). A cannula was inserted in the left lateral ventricle, and 5 microl of 8.5 mM Gd-DTPA was injected as a CSF marker. Changes in the image intensity of the CSF were measured every 30 s, and the turnover rate of CSF (k) in the left lateral ventricle was obtained from the dilution of Gd-DTPA, based on the assumption of a single compartment model. In the control conditions, k was 0.158 +/- 0.009 min(-1) at an arterial blood CO(2) tension (pCO(2)) of 38.6 +/- 2.2 mmHg (n = 10), which corresponds to the CSF secretion rate of 3.6 microl min(-1). The k value was decreased (0.078 +/- 0.010 min(-1), n = 4) by a carbonic-anhydrase inhibitor (acetazolamide). The turnover rate was decreased by hypocapnia (0.094 +/- 0.019 min(-1), pCO(2) = 24.7 +/- 2.9 mmHg, n = 4), and it increased gradually and reached a plateau level as a result of hypercapnia (0.194 +/- 0.011 min(-1), pCO(2) = 104.5 +/- 7.1 mmHg, n = 10). These results suggested that CO(2) upregulates the secretion of CSF in the rat.

Animals↗

A sandwich enzyme immunoassay for human pancreatic elastase III.

To develop a method for the determination of pancreas injuries using a pancreas-specific antigen as a marker, human elastase III was purified from the pancreas by chromatographic methods. A rabbit anti-human elastase III antibody was prepared, and this antibody was confirmed using immunoblotting to react only with elastase III among proteins from the pancreas. A sensitive sandwich enzyme immunoassay for human elastase III was developed. The detection limit for human elastase III was 0.3 pg (10 amol) per assay. Proteins extracted from the pancreas showed the strongest response, whereas reactions of the other organs were less than the detection limit. These results suggest that a sandwich enzyme immunoassay for human elastase III is useful for the determination of pancreas injury.

Animals↗

High expression of vascular endothelial growth factor is associated with liver metastasis and a poor prognosis for patients with ductal pancreatic adenocarcinoma.

BACKGROUND: Vascular endothelial growth factor (VEGF), a recently identified growth factor with significant angiogenic properties, is a multifunctional angiogenic cytokine that is expressed in many tumors. High VEGF expression has been shown to correlate with the incidence of metastasis and poor prognosis in various cancers. In this study, the authors investigated VEGF expression and microvessel density (MVD) in ductal pancreatic adenocarcinoma and examined the correlations among VEGF expression, clinicopathologic factors, and clinical outcome. The authors especially focused on the correlation between VEGF expression and liver metastasis. METHODS: Paraffin embedded tumor specimens of 142 surgically resected pancreas carcinoma were immunohistochemically stained for VEGF and MVD. The correlations among VEGF expression and MVD, clinicopathologic factors, and clinical outcome were then statistically analyzed. RESULTS: One hundred thirty-two (93%) of 142 ductal pancreatic adenocarcinomas were positive for VEGF protein by immunohistochemistry. A significant correlation was observed between VEGF positivity and MVD (P < 0.0001). Multivariate logistic regression analysis indicated a significant association between high VEGF expression and liver metastasis (P = 0.010) but no other factors, such as age, tumor size, histologic type, lymph node metastasis, venous invasion, neural invasion, peritoneal metastasis, or local recurrence. Patients with tumors that showed moderate or high VEGF expression had significantly shorter survival than patients with low VEGF expression or none at all in their tumors (P < 0.05). CONCLUSIONS: These results indicate that VEGF expression is closely correlated with MVD and seems to be an important predictor for both liver metastasis and poor prognosis in ductal pancreatic adenocarcinoma.

Adult↗

A sandwich enzyme immunoassay for pulmonary surfactant protein D and measurement of its blood levels in drowning victims.

A sensitive sandwich enzyme immunoassay for human pulmonary surfactant protein D (SP-D) was developed and used to examine the blood SP-D levels of drowning victims. Human SP-D was purified from amniotic fluid by chromatographic methods, and an antibody against human SP-D was prepared. A polystyrene ball coated with anti-SP-D IgG was incubated with purified human SP-D, and then with anti-SP-D Fab'-peroxidase conjugate. Peroxidase activity bound to the polystyrene ball was assayed by fluorometry using 3-(4-hydroxyphenyl)propionic acid as the hydrogen donor. The detection limit of human SP-D was 5.2 pg per assay tube. Examination of cross-reactions of this sandwich enzyme immunoassay with proteins from other human organs showed it to be highly specific for lung, and Northern blot analysis detected specific SP-D mRNA expression only in lung. The SP-D concentration of normal human serum was 6.4+/-2.7 (mean+/-S.D.) ng ml(-1) (n=20). The recovery rates of 0.52 ng and 5.2 ng SP-D added to 5 microl normal human serum were 93.6+/-2.7% and 93.6+/-6.1%, respectively. Blood SP-D levels of victims from the saltwater drowning group (n=14) revealed higher concentrations (105.8+/-53.7 ng ml(-1)), while freshwater drowning victims (n=12) were estimated to be 74.1+/-43.9 ng ml(-1). The SP-D levels of 15 subjects who died of hemorrhage (n=5), heart failure (n=8), traumatic shock (n=1), and electrocution (n=1) were lower (22.0+/-8.5 ng ml(-1)), and those of asphyxia victims (n=10) were slightly higher (36.2+/-17.1 ng ml(-1)) than those of other causes of death, except for drowning. These results suggest that in drowning victims, SP-D flowed into the systemic circulation by physiological and physical mechanisms, and the differences of blood SP-D levels between saltwater drowning and freshwater drowning victims are presumed to be influenced by the type of agony and/or the length of survival time in water.

Adolescent↗

Slice-selective proton double quantum filtered MRI of joint connective tissues.

1H double quantum filtered (DQF) imaging has been shown to highlight tendons. In this work the DQF magnetic resonance imaging pulse sequence is extended to include slice selection. The short transverse relaxation time of the 1H nuclear magnetic resonance in connective tissues, presents a stringent demand on the application of gradients and soft radiofrequency pulse lengths needed for slice selection. In the present work a slice selection pulse sequence is implemented by postponing the application of the slice refocusing gradient to the period after the last pulse just before the acquisition. Slice-selective DQF images of rat lower leg and knee are given to demonstrate the efficacy of the technique.

Animals↗

Time-course magnetic resonance imaging of rat pancreatic cyst after experimental pancreatitis.

Fast magnetic resonance (MR) imaging of the rat pancreas was carried out using a snapshot method to observe three-dimensional (3D) and temporal development of the pancreatic cyst after experimental pancreatitis. Acute pancreatitis was induced by a retrograde infusion of the trypsin-taurocholate solution into the pancreatic duct in 23 rats, of which seven survived for one month. Under 2% enflurane anesthesia, (1)H images of the rat abdomen were taken by a 4.7 T magnetic resonance spectrometer under spontaneous breathing. 3D images of the pancreas and cyst were reconstructed from the axial, sagittal and coronal images taken before, 24 h, 7 days, 14 days, 21 days and 28 days after the induction of pancreatitis. The 3D images reconstructed from different slice orientations at each time point showed good agreement with each other. The calculated volumes of the cyst on 7th, 14th, 21st, and 28th day were 0.3 +/- 0.1, 0.8 +/- 0.3, 2.1 +/- 0.6, 6.5 +/- 1.3 mL, respectively. The cystic fluid volume on 28th day was 6.4 +/- 1.4 mL, which confirmed reliability of volume measurement by MR imaging. Fast MR imaging (snapshot) together with 3D reconstruction allows us to understand the detailed chronological and spatial development of pancreatic cyst after acute pancreatitis in rats.

Acute Disease↗

A novel method of species identification using human muscle-specific beta-enolase.

A novel method of species identification using a sensitive sandwich enzyme immunoassay for human muscle-specific beta-enolase was used to analyze bloodstains and skeletal muscle. Human beta-enolase is detectable in human blood at dilutions up to 3 x 10(3) and human muscle extract (0.1 g/ml) at dilutions up to 5 x 10(6) using a sandwich enzyme immunoassay. The cross-reactivities of both blood and skeletal muscle extracts from other species were 0.01 or less. When human skeletal muscle extract was added in a final concentration of 10 mg/ml, the ratio of beta-enolase to total protein in bloodstains was approximately 1000, whereas the addition of skeletal muscle extract of other species resulted in a ratio of less than 10. Application of this method in a practical case proved that human muscle-specific beta-enolase as a marker for species identification is very effective in forensic practice.

Journal Article↗

Determination of pancreas injury from bloodstains using human pancreatic elastase III as a marker.

A sensitive sandwich enzyme immunoassay for human pancreatic elastase III as a method to identify pancreas injuries from blood or bloodstains was evaluated. The serum levels of human elastase III from healthy adults (n=24) were estimated to be 1.15 +/- 0.6 (+/- SD) ng/ml. The recovery rates of elastase III added to normal human serum were estimated to be 96.3%. Elastase III levels in contents of various digestive organs were assayed and found to be high in the contents of the large intestine. For detection of human elastase III on weapons, samples were prepared from disposable scalpels that had been used to cut skin and skeletal muscle, and then to cut various organs. The mean ratio of elastase III to total protein (ng elastase III/mg protein) on scalpels that had been cut the pancreas (n=11) was 4956+/-3067 (+/- SD), whereas the ratios from other organs were much lower except, in case of several digestive organs. The higher elastase III levels detected in these digestive organs seemed to stem from the amount of intestinal contents adhering to the scalpels. These results suggest that determination of pancreatic elastase III in blood or bloodstains using a sandwich enzyme immunoassay is a very useful and effective tool for identification of pancreas injury in forensic practice.

Journal Article↗

Changes in mRNA expression levels of synaptic- and target tissue-specific proteins after organophosphate exposure.

We examined the effects of organophosphate exposure on mRNA expression levels of synaptic- and target tissue-specific proteins in rats. We treated rats with a single dose of Disulfoton (O,O-diethyl S-2-ethylthioethyl phosphorodithioate) and used quantitative reverse transcription-polymerase chain reaction (RT-PCR) to measure the time course of changes in the levels of mRNAs encoding acetylcholinesterase (AChE), nicotinic acetylcholine receptor (nAChR), beta-enolase (MSE), and gamma-enolase (NSE) in soleus muscles and sciatic nerves. The expression levels of synaptic genes encoding AChE in both tissues were significantly decreased, with a nadir at 12h after the administration, and this down-regulation lasted for up to 30 days after administration. Similarly, the level of nAChR mRNA in soleus muscle also decreased, with a nadir at 48 h after administration and a return to 95% of that of the control levels by 30 days after administration. These results indicate that administration of organophosphate can decrease AChE and nAChR expression in the neuromuscular junction, and are suggestive of multiple mechanisms of down-regulation of both AChE and nAChR, some of which might involve alterations at the transcriptional level. The transcript level of the target tissue-specific gene encoding MSE in soleus muscle was slightly decreased, with a nadir at 48 h after administration, and was still lower than that of the control level after 30 days. In contrast, the level of the NSE transcript in sciatic nerve significantly increased within 2 h, and this up-regulation was sustained until 30 days after administration. Although the functions of either of these enolases are not completely established, up-regulation of NSE mRNA may be a marker for the nervous system abnormality following organophosphate exposure. All of these phenomena may contribute to the long-lasting neurotoxic effects observed after developmental exposure to organophosphates.

Journal Article↗

New xenicane diterpenoids from the gorgonian Acalycigorgia inermis.

Acalycixeniolides D-G [corrected] (1-4), four new diterpenoids of the xenicane class, have been isolated from the gorgonian Acalycigorgia inermis. The structures of these compounds have been determined by combined spectroscopic methods. These compounds exhibited cytotoxicity against a human leukemia cell-line.

Animals↗

New triterpenoid saponins from the sponge Melophlus isis.

Four new triterpenoid saponins were isolated, along with two known 30-norlanostane-type saponins- sarasinosides A(1) (1) and A(3) (2)-from the sponge Melophlus isis collected from Guam. The structures of these new compounds (3-6) proved to be 30-norlanosta-8(14),24-dien-23-ones bearing two hydroxyl groups or the corresponding methoxy groups at the 9alpha,15alpha- and 9alpha, 15beta-positions and the pentasaccharide portion identical with those of 1 and 2 at the 3beta position, by spectral, chemical, and GC analyses.

Animals↗

Identification of remains by sequencing of mitochondrial DNA control region.

The maternity of two newborns who were murdered and abandoned >5 and 10 years were analyzed by amplification and direct sequencing of mitochondrial DNA (mtDNA) control regions. Sequences of two hypervariable segments from each femur bone sample and the blood of the putative mother showed four mutations in hypervariable region I and two mutations in addition to two nucleotide insertions in hypervariable region II compared with the reference sequence, and all sequences were identical. The genotype of these individuals is found to be relatively rare in the Japanese population, and it was strongly suggested that both sets of newborn remains really were children of the putative mother. Sexes of the remains were determined to be female and male by amplifying a segment of the X-Y homologous gene, amelogenin. These results demonstrate that sequencing of mtDNA is a useful tool for genetic identification of aged and decomposed materials.

Amelogenin↗

In vivo NMR micro-imaging of kidney and liver of mouse at 9.4 T.

NMR micro-images of the kidney and liver were measured at 9.4 T in intact mouse, schistosoma Mansoni-infected mouse, and lupus nephritis in an MRL/lpr mouse. High-field NMR imaging has the advantages of sensitivity, spatial resolution, and tissue contrasts based on longitudinal and transverse relaxations, magnetic susceptibility differences and blood flow.

Animals↗

Characteristics of proton NMR T(2) relaxation of water in the normal and regenerating tendon.

The molecular behavior of water in normal and regenerating tendons was analyzed using the transverse relaxation time (T(2)) measured by spin-echo proton nuclear magnetic resonance ((1)H-NMR) spectroscopy at 2.34 T (25 degrees C). A section of the Achilles tendon was dissected from an anesthetized Japanese white rabbit, and its longitudinal axis was oriented at 0, 35, 54.7, 75, and 90 degrees to the static magnetic field. In the normal tendon, the T(2) relaxation of water presented biexponential relaxation and anisotropy in both the long T(2) (5.41 to 6.21 ms) and short T(2) (0.41 to 1.43 ms) components, in which the greatest values were obtained at 54.7 degrees. However, the range of the anisotropy was much narrower than we expected from the (1)H dipolar interaction of water bound to the collagen fibers in the tendon. The apparent fractions of water proton density also varied with orientation: the fraction of the longer T(2) components was at its maximum at 54.7 degrees. These results suggest that a simple two-compartment model could not be applicable to orientational dependency of the T(2) value of the tendon, and the well ordered water in the short T(2) relaxation component may show an elongated T(2) relaxation time that falls in the range of the long T(2) relaxation component at 54.7 degrees. This hypothesis can explain both the narrower range of the T(2) relaxation time and the orientational dependency on the apparent fraction of (1)H density. Regenerating processes of the Achilles tendon were followed for 18 weeks by analyzing the T(2) relaxation time. There is only a long T(2) relaxation time component (21.8 to 28.0 ms) up to 3 weeks after transection. Biexponential relaxation is revealed at 6 weeks and thereafter, whereby (i) the T(2) relaxation times become shorter, (ii) there is anisotropy in the short and long T(2) values, and (iii) the orientational dependency of the apparent fraction of water proton density becomes evident with maturation of the regenerating tendon. From these results, the (1)H T(2) relaxation time of water might be used to monitor the healing process of collagen structures of the tendon non-invasively.

Animals↗

Cavernous sinus hemangioma treated with gamma knife radiosurgery: usefulness of SPECT for diagnosis--case report.

A 79-year-old female presented with cavernous sinus hemangioma manifesting as double vision due to right oculomotor and trochlear nerve pareses. Computed tomography and magnetic resonance imaging revealed bony erosion and a right cavernous sinus tumor with "tail sign" after contrast medium administration. Thallium-201 (201Tl) single photon emission computed tomography (SPECT) showed low uptake within the tumor, and technetium-99m-human serum albumin-diethylenetriaminepenta-acetic acid SPECT disclosed high uptake within the tumor. 201Tl SPECT usually shows very high uptake in meningiomas and malignant tumors, so the tumor was considered to be an unrelated benign tumor. The patient underwent partial resection of the tumor. Histological examination of the specimen confirmed cavernous hemangioma. The oculomotor nerve paresis partially improved. Gamma knife radiosurgery was carried out 4 months after the operation. The tumor markedly shrank with full recovery of extraocular movement 6 months after radiosurgery. SPECT is useful for distinguishing cavernous sinus hemangiomas from other cavernous tumors. Radiosurgery should be performed after partial resection or biopsy for cavernous sinus hemangiomas and may be the initial treatment for patients with small cavernous sinus hemangioma if the diagnosis can be established based on neuroimaging.

Aged↗

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↗

Anisotropic and restricted diffusion of water in the sciatic nerve: A (2)H double-quantum-filtered NMR study.

The signals of water in the different compartments of rat sciatic nerve are resolved in the (2)H double-quantum-filtered NMR spectrum, due to their different quadrupolar splittings and relaxation rates. This resolution allowed the independent measurement of the water diffusion coefficients in the different compartments. The water diffusion in all three compartments, the endoneurium, the epineurium and the axon was found to be anisotropic. Parallel to the nerve fiber the average intraxonal water diffusion coefficient was 1.11 x 10(-5) cm(2)/sec, while in the perpendicular direction the diffusion is heavily restricted. The average perpendicular diffusion coefficient ranged from 0.29 x 10(-5) cm(2)/sec to 0.05 x 10(-5) cm(2)/sec for diffusion times of 7 msec and 50 msec, respectively. Assuming restricted diffusion in nonpermeable cylinders, intra-axonal mean diameters of 6.0, 7.4 and 9.0 microm were obtained for nerves taken from three different rats. Magn Reson Med 42:461-466, 1999.

Animals↗