Search PubMed⌕ Search

Biomedical subjects

C Y Kim

Publications and source records attributed to C Y Kim.

At least 181 records · Page 10Linked to original sources
PubMed1988

Peripheral cholangiocarcinoma and clonorchiasis: CT findings.

Sixteen patients with peripheral cholangiocarcinoma of the liver were examined with computed tomography (CT). None of the 16 patients presented with jaundice or had documented cirrhosis. On scans obtained both before and after the injection of contrast material, the tumors were depicted as low-attenuation masses in all cases, with wide variations in homogeneity. The tumor margin was irregular in 12 cases, and there was minimal contrast enhancement of the tumor in 14 cases. In 11 (69%) patients, CT demonstrated masses of markedly low attenuation, which corresponded to areas of diffuse microcystic change seen at histologic examination of resected specimens. In ten (63%) patients, the results of stool or intradermal tests for Clonorchis sinensis were positive. In all ten cases of clonorchiasis, mild, diffuse dilatation of the intrahepatic bile ducts was seen in addition to the low-attenuation masses, but there was no dilatation of the extrahepatic biliary tree. In five of the ten patients with clonorchiasis, stippled or aggregated, powderlike areas of high attenuation were seen on precontrast CT scans; at pathologic examination, those areas were found to be mucin. Extrahepatic metastases were demonstrated in ten (63%) patients. Peripheral cholangiocarcinoma should be the primary diagnostic consideration when these characteristic CT findings are detected in a noncirrhotic patient.

Adenoma, Bile Duct↗
PubMed1988

Computerized quality control of radioimmunoassay in Korea.

Automated data processing and quality control of radioimmunoassays offer not only increased speed but also a more thorough and statistically rigorous analysis of results. An external quality assessment scheme for serum thyroxine, triiodothyronine and thyroid stimulating hormone (TSH) assays was performed in five nuclear medicine laboratories in Korea to compare with the assay performances of the World Health Organization Radioimmunoassay Program. The required radioimmunoassay kits were supplied through the International Atomic Energy Agency (IAEA). We have determined the weighted root mean squared error, and variance ratio as the indices of standard curve and also the average batch coefficient of variation (ABCV) as the parameters of response error relationship curve and precision profile. There was a good fit for the triiodothyronine assay, but 3 of 5 laboratories showed possible bad fit in the T4 and TSH assay systems. The ABCV was less than 5 percent for the T3 and T4 assay system, however for the TSH system, only 1 laboratory showed the ABCV value of less than 5 percent. We have also calculated the within batch variation (drift) and between laboratory variations.

Electronic Data Processing↗
PubMed1987

Studies on avian erythrocyte metabolism. XVI. Accumulation of 2,3-bisphosphoglycerate with shifts in oxygen affinity of chicken erythrocytes.

The ability of the chicken erythrocyte to accumulate 2,3-bisphosphoglycerate (2,3-P2-glycerate) and its effect upon the oxygen affinity (P50) of the cell suspensions have been determined. Erythrocytes from chick embryos, which contain 4-6 mM 2,3-P2-glycerate, and from chickens at various ages, which contain 3-4 mM inositol pentakisphosphate but no 2,3-P2-glycerate, were incubated with inosine, pyruvate, and inorganic phosphate. Red blood cells from 20-day chick embryos incubated in Krebs-Ringer, pH 7.45, containing 20 mM inosine and 20 mM pyruvate had an increase in 2,3-P2-glycerate from 4.3 to 11.9 mM after 4 h. Importantly, as 2,3-P2-glycerate concentration increased there was a corresponding increase in P50 of the cell suspension. Further, erythrocytes from 9- and 11-week, and 7-, 14-, 24-, and 28-month-old chickens when incubated similarly with inosine and pyruvate accumulated 2,3-P2-glycerate with corresponding increases in P50 of the cell suspensions. The ability of the red cell to accumulate this compound under the incubation conditions used apparently decreases with age of the bird (e.g., 11.9 mM in the 20-day embryo to 1.1 mM in the 28-month-old chicken after 4 h incubation). Despite the presence of significant amounts of inositol-P5, the accumulation of 2,3-P2-glycerate markedly decreases oxygen affinity of the cell suspensions. The delta P50/mumol increase in 2,3-P2-glycerate in the red cells of the 20-day chick embryo after 4 h incubation is 1.5 Torr; conversely, the delta P50/mumol decrease in 2,3-P2-glycerate in the red cells of the 17-day embryo after 6 h incubation in the presence of sodium bisulfite is 2.8 Torr. The demonstrated ability of the chicken erythrocyte to accumulate 2,3-P2-glycerate in response to certain substrates suggests that regulation of concentration of this compound could contribute significantly to regulation of blood oxygen affinity in birds.

2,3-Diphosphoglycerate↗
PubMed1983

19-Hydroxylation of 18-hydroxy-11-deoxycorticosterone catalyzed by cytochrome P-45011 beta of bovine adrenocortex.

When 18-hydroxy-11-deoxycorticosterone was incubated with adrenocortical mitochondria fortified by adding exogenously adrenodoxin reductase and adrenodoxin in the presence of an NADPH-generating system, the steroid was converted to two products which were separated by high performance liquid chromatography. The retention time of one product was identical with that of 18-hydroxycorticosterone, an expected product of 11 beta-hydroxylation, whereas the retention time of the other was not coincident with those of any other corticosteroids examined. Production of the unidentified substance was also shown when 18-hydroxy-11-deoxycorticosterone was incubated with purified cytochrome P-45011 beta and its electron transport system. The ratio of the two products was always constant, even when various incubation conditions were employed with regard to reaction time, the substrate concentration, and the cytochrome concentration. Structural determination of the unidentified product was conducted by mass spectrometry and 1H NMR spectrometry. The results of these analyses indicated that the substance was 18,19-dihydroxy-11-deoxycorticosterone, a hitherto unreported corticosteroid.

18-Hydroxydesoxycorticosterone↗
PubMed1983

Regulation of 18-hydroxycorticosterone formation in bovine adrenocortical mitochondria.

The conversion of deoxycorticosterone to 18-hydroxycorticosterone was examined by using sonicated mitochondrial suspension of bovine adrenocortex. The KM's of deoxycorticosterone for the 11 beta- and 18-hydroxylations were in the same range (1 microM), while the turnover number for the 11 beta-hydroxylation (50 nmol/min/nmol cytochrome P-450) was 6 times as great as that for the 18-hydroxylation (7.3). The KM and turnover number for the 18-hydroxylation of corticosterone were 6 microM and 0.4, respectively. Those for the 11 beta-hydroxylation of 18-hydroxy-11-deoxycorticosterone were 120 microM and 5. When products were analysed in the incubation of deoxycorticosterone with the mitochondrial suspension containing a larger amount of cytochrome P-450, the formation of 18-hydroxycorticosterone was observed in addition to the formation of corticosterone and 18-hydroxy-11-deoxycorticosterone. The kinetic interrelation between the two pathways was further examined together with consideration of the cytochrome P-450-linked hydroxylation system. The result suggests that the pathway via 18-hydroxy-11-deoxycorticosterone substantially participates in the formation of 18-hydroxycorticosterone from deoxycorticosterone. The perturbation of this network by an artificial means, such as the addition of Triton X-100, revealed that the detergent (0.02%) facilitated the production of 18-hydroxycorticosterone from deoxycorticosterone, regardless of its inhibitory effect on the production of corticosterone and 18-hydroxy-11-deoxycorticosterone from deoxycorticosterone. These studies provide an important insight into the regulation mechanism of 18-hydroxycorticosterone formation from the precursors on the mitochondrial level.

11-Hydroxycorticosteroids↗
PubMed1982

Hepatitis B virus and primary hepatocellular carcinoma: family studies in Korea.

Chronic infection with hepatitis B virus (HBV) is closely associated with the etio-pathogenesis of primary hepatocellular carcinoma (PHC). It has been proposed that infection with HBV early in life, frequently transmitted by an HBV-carrier mother, leads to persistent infection with HBV, which in turn is associated with the development of chronic active hepatitis (CAH), post-necrotic cirrhosis and PHC. If this view is correct, then there should be clustering of chronic carriers of HBV in families of patients with chronic liver disease. We tested this hypothesis in Korea by collecting serum from 132 patients with these chronic liver diseases admitted to the Seoul National University Hospital and 664 of their first-degree relatives. Controls (636) were members of two churches in Seoul and a rural village population; 261 of the controls were between the ages of 30 and 59, the age range that included 95% of the cases of chronic liver disease. Sera were assayed for hepatitis B surface antigen (HBsAg), antibody to HBsAg (anti-HBs) and antibody to hepatitis B core antigen (anti-HBc). Almost all cases showed evidence of present or past infection with HBV; 80% were HBsAg(+) and 14% were anti-HBs(+); 100% of 47 cases of PHC, 100% of 35 cases of cirrhosis, and 94% of 50 cases of CAH were anti-HBc(+); 6% of males and 4% of females in control population (30-59 years of age) were HBsAg(+), 71% were anti-HBc(+), and 51% were anti-HBs(+). HBsAg(+) patients with chronic liver disease tended to be younger than HBsAg(-) patients with anti-HBs or anti-HBc antibodies. Mothers of patients with more frequently (HBsAg(+) (9 of 33) than age-matched women in the control population (0 of 34) or wives of patients (5 of 68). Five of 23 fathers were also HBsAg(+) compared with 1 of 25 age-matched controls. As first observed in Africa, there was a deficit of anti-HBs in the fathers of cases compared with the controls. Siblings of patients were frequently HBsAg(+) (45% of 154), with the highest prevalence in brothers (53%). Family history shows that five fathers, two mothers and five brothers of cases have died of PHC. These data are compatible with the hypothesis tested and lend further support to the view that prevention of infection with HBV will lead to a marked decrease in the incidence of CAH, cirrhosis and PHC in areas where these diseases are endemic. Members of the families of patients with these diseases are at high risk of developing persistent infection with HBV and chronic liver disease. It would be appropriate to focus preventive strategies on infants and children in such families.

Africa↗
PubMed1982

Studies on avian erythrocyte metabolism. XII. The synthesis and degradation of inositol pentakis (dihydrogen phosphate).

The pathway(s) of synthesis and degradation of inositol 1, 3, 4, 5, 6 pentakis (dihydrogen phosphate) (inositol-P5), found predominantly in the avian erythrocyte, are unknown. Myo-inositol (inositol), D-glucose, inosine, and phosphate have been studied as potential precursors of inositol-P5 synthesis in chicken erythrocytes. Whole blood from chickens at several ages has been incubated for prolonged periods and the concentration of inositol-P5 measured to determine the ability of the avian erythrocyte to catabolize inositol-P5. Incubation of erythrocyte suspensions from 5-day chicks with [U-14 C]myo-inositol (inositol) for 17 hr lead to the appearance of 19.8% of the radioactivity in the aqueous acid-soluble extract of the erythrocytes (RBC). Fractionation of this extract on an anion exchange column yielded five major radioactive peaks, three of which represent 1) free myo-inositol, accounting for 63.5% of the radioactivity; 2) myo-inositol monokis (dihydrogen phosphate) (inositol-P), representing 1.6% of the radioactivity; and 3) inositol 1, 3, 4, 5, 6 pentakis (dihydrogen phosphate) (inositol-P5), representing 27.0% of the label in the erythrocyte. Sodium fluoride did not inhibit the incorporation of [U-14 C]myo-inositol into inositol-P5. Similar incubations with D-[U-14 C]-glucose and [U-14 C]-inosine yielded no incorporation of radioactivity into inositol-P5. These data are consistent with the interpretation that inositol is the major precursor for synthesis of inositol-P5 in chick red cells. Incubation of whole blood from 1-, 5-, and 42-day chicks and mature birds at 40 C for as long as 72 hr resulted in increases in RBC inorganic phosphate (Pi) thought due primarily to depletion of adenosine triphosphate (ATP). Inositol-P5 content of RBC of 5- and 42-day birds decreased 28 and 20%, respectively, after 72 hr, but no change was noted in inositol-P5 levels of RBC from mature birds. The red cells of the mature bird appear to be unable to catabolize inositol-P5 at significant rates. The apparent inability of the chicken erythrocyte to alter readily its concentration of inositol-P5 suggests that the hemoglobin oxygen delivery system of birds may be less adaptable to changing oxygen requirements by regulating the concentration of hemoglobin modulator than is that of the mammals.

Adenosine Triphosphate↗
PubMed1981

Effect of ether, ethanol and aqueous extracts of ginseng on cardiovascular function in dogs.

Ether, ethanol and aqueous extracts of ginseng were serially prepared from Korean ginseng plants. Each extract in the dose of 40 mg/kg was administered intravenously to ten dogs under light halothane anesthesia while 11 cardiovascular variables were compared during the ensuing two hours. The variable included cardiac output, stroke volume, heart rate, mean arterial pressure, pulse pressure, central venous pressure, total peripheral resistance, pH, PaCO2, PaO2 and base deficit. Following the administration of the ether extract (40 mg/kg) the heart rate and the central venous pressure decreased significantly. The administration of ethanol extract (40 mg/kg) caused a significant decrease in the heart rate and the mean arterial pressure. After the administration of the aqueous extract (40 mg/kg) the cardiac output, stroke volume and central venous pressure were significantly decreased, while the total peripheral resistance was significantly increased.

Animals↗
PubMed1979

Effects of the second (ethanol) extract of ginseng on the cardiovascular dynamics of dogs during halothane anesthesia.

An electromagnetic flowmeter probe was chronically implanted around the ascending aorta in a group of dogs. Subsequently, ten dogs were lightly anesthetized with halothane (0.75%), and a second (ethanol) extract of ginseng (40 mg/kg) was administered intravenously. Five dogs were anesthetized without the administration of ginseng. Eleven cardiovascular variables including cardiac output, stroke volume, heart rate, mean arterial pressure, pulse pressure, central venous pressure, total peripheral resistance, pH, PaCO2, PaO2, and base deficit were compared for two hours. The heart rate and mean arterial pressure were significantly decreased following ginseng. There were no other meaningful changes in either group.

Anesthesia, Inhalation↗
PubMed1979

Effects of the third (aqueous) extract of ginseng on the cardiovascular dynamics of dogs during halothane anesthesia.

An electromagnetic flowmeter probe was chronically implanted around the ascending aorta in a group of dogs. Subsequently, ten dogs were lightly anesthetized with halothane (0.75%) and the third (aqueous) extract of ginseng (40 mg/kg) was administered intravenously. Five dogs were anesthetized without the administration of ginseng. Eleven cardiovascular variables including cardiac output, stroke volume, heart rate, mean arterial pressure, pulse pressure, central venous pressure, total peripheral resistance, pH, PaCO2, PaO2, and base deficit were compared. The cardiac output, stroke volume, and central venous pressure were decreased significantly, while total peripheral resistance was increased significantly following ginseng.

Anesthesia, Inhalation↗
PubMed1979

Can an extract of deer antlers alter cardiovascular dynamics?

Ten (10) dogs were maintained under 0.75% halothane anesthesia while 11 cardiovascular parameters were studied before and following intravenous administration of an extract prepared from deer antlers. The eleven variables including cardiac output, stroke volume, heart rate, mean arterial pressure, pulse pressure, central venous pressure, total peripheral resistance, pH, PaCO2, PaO2 and base line deficit were studied. Stroke volume was consistently elevated during the period of observation and significantly elevated at two time intervals. Other values were not altered significantly. Extract from deer antlers does not appear to have a great acute effect on the cardiovascular system of this animal model.

Animals↗