Search PubMed⌕ Search

Biomedical subjects

K Okuda

Publications and source records attributed to K Okuda.

At least 559 records · Page 31Linked to original sources
PubMed1991

Therapy with mitoxantrone, ifosfamide, vindesine, and prednisolone for malignant lymphoma with adjustable doses and timing of courses.

Thirty-seven patients with malignant lymphoma were treated with mitoxantrone, ifosfamide, vindesine, and prednisolone. The time among courses was not fixed, being decided by the time for recovery from the leukopenia caused by the treatment. The drug dose was adjusted after the initial course. Of the 12 patients treated for the first time, eight had a complete remission and two had a partial response. Of the 18 patients who relapsed after another drug regimen, six had a complete remission and seven had a partial response. The SD of the leukocyte nadirs decreased after the first course, and time needed for recovery from leukopenia tended to shorten during treatment. Side effects seemed mild, and we can use many drugs safely in a short term without long drug-free intervals. Response rates were satisfactory, compared with other report, so this method of timing the start of courses with adjustment of the dose seems useful.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1991

Lactate analyzer with continuous blood sampling for monitoring blood lactate during physical exercise.

To monitor changes in the concentration of blood lactate during physical exercise, we used an automated lactate analyzer based on an electro-enzymatic method with continuous blood sampling through a catheter. The lactate concentration was measured every 2 min; between measurements, the instrument was calibrated with a lactate standard. Ascorbic acid, bilirubin, hemoglobin, creatinine, uric acid, and glucose did not interfere with the measurements. The lactate concentrations in blood samples from apparently healthy subjects before and after exercise correlated well (r = 0.993) with results by the conventional enzymatic method. We measured the blood lactate concentrations in nine apparently healthy volunteers during exercise on a treadmill with an increasing workload. The point at which lactate concentrations started to increase was detected easily. Thus, the lactate analyzer is suitable for monitoring changes in blood lactate concentrations during exercise.

Autoanalysis↗
PubMed1991

[Multiple discriminant analysis for prognosis of refractory anemia].

Forty-eight patients with refractory anemia (RA) were retrospectively analyzed for their prognosis and subclassified into three groups: 12 patients with hematological improvement (A), 23 patients with no changes (B), and 13 patients with progression to RAEB or acute leukemia (C). For all patients, the median survival were 49.2 months, and the rate of leukemic transformation was 16%. The median survivals were 60.6, 32.1, and 17.9 months, respectively, for groups A, B and C. The factors indicating poor prognosis were low reticulocyte counts, low neutrophil alkaline phosphatase activity, low% red cell utilization, high M/E ratio, high blast percentage in the bone marrow and cytological abnormalities in the granulocyte and megakaryocyte series. By using multiple discriminant analysis, we obtained a formula for the prognostic estimation with a discrimination probability of 62.5%. This formula could predict either the patients with good (Y greater than 0.85) or poor (Y less than 0.59) prognosis, and might be useful to select the treatment for this intractable anemia at the time of diagnosis.

Adolescent↗
PubMed1991

Pancreatic pseudocyst in the left hepatic lobe: a report of two cases.

The ultrasound and computed tomographic imaging features in a rare pancreatic pseudocyst of the liver are described in two patients. The pseudocysts occurred in the left lobe in both cases, one after a traumatic injury and the other after alcoholic pancreatitis. The possible topographical sequences with which pancreatic secretions entered the left hepatic lobe to form a cyst are discussed.

Adult↗
PubMed1990

Unique property of liver mitochondrial P450 to catalyze the two physiologically important reactions involved in both cholesterol catabolism and vitamin D activation.

The cDNA for vitamin D 25-hydroxylase in rat liver mitochondria was transfected in COS cells in order to confirm our previous postulation that both 5 beta-cholestane-3 alpha, 7 alpha, 12 alpha-triol 27-hydroxylation and vitamin D 25-hydroxylation are catalyzed by a common enzyme. As a result it was found that both enzyme activities could be reconstituted from the solubilized extract of mitochondria of these cells, NADPH, NADPH-adrenodoxin reductase and adrenodoxin, giving unequivocal evidence that the two enzyme activities are catalyzed by a common enzyme.

25-Hydroxyvitamin D3 1-alpha-Hydroxylase↗
PubMed1990

The effect of non-insulin-dependent diabetes on serum concentrations of tumor-associated carbohydrate antigens of CA19-9, CA-50, and sialyl SSEA-1 in association with the Lewis blood phenotype.

Serum concentrations of the tumor-associated carbohydrate antigens CA19-9, CA-50, and sialyl SSEA-1 were measured in non-insulin-dependent diabetic patients without diseases causing the elevation of those antigens, and the relationship to diabetic conditions was studied. The patients of the Lewis blood group phenotype of Lea (23%) had higher serum CA19-9, CA-50, and sialyl SSEA-1 than those of Leb (67%) and Le(-) (10%). Lea patients with high HbA1c (greater than 10%) had significantly higher serum CA19-9 and CA-50 than those with low HbA1c (less than or equal to 7%). Leb patients with high HbA1c also had elevated CA19-9 and sialyl SSEA-1. In Leb patients, diabetic nephropathy was associated with increased CA19-9 levels. Diabetic retinopathy was also accompanied by high carbohydrate antigens in Leb patients, but the difference was not significant. Leb patients treated with sulfonylurea or insulin had increased CA19-9 and CA-50. The changes in serum concentrations of these carbohydrate antigens might have some relationship not only to the Lewis blood phenotype, but also to diabetes.

Aged↗
PubMed1990

Molecular cloning and sequence analysis of cDNA encoding human cholesterol 7 alpha-hydroxylase.

A complete cDNA clone encoding human cholesterol 7 alpha-hydroxylase has been isolated using a rat P-450ch7 alpha cDNA insert [(1989) FEBS Lett. 257, 97-100] as a probe and totally sequenced. The cDNA contained 1512-base pair open reading frame encoding 504 amino acid residues (Mr 57,630), 39-base pair 5'-untranslated region 1322-base pair 3'-ultranslated region including 20 nucleotides of poly A tail in the total length of 2873 base pairs. The deduced amino acid sequence showed 82% similarity to rat P-450ch7 alpha. Unique amino acid residues were observed in putative binding domains for heme and steroid which are highly conserved in most steroidogenic P-450s.

Amino Acid Sequence↗
PubMed1990

Rat liver cholesterol 7 alpha-hydroxylase. Pretranslational regulation for circadian rhythm.

A complete cDNA encoding cholesterol 7 alpha-monooxygenase (EC 1.14.13.17) which had been isolated from rat liver cDNA libraries by using specific antibodies to the enzyme (Noshiro, M., Nishimoto, M., and Okuda, K. (1989) FEBS Lett. 257, 97-100) was totally sequenced. The cDNA contained a 1,509-base pair open reading frame encoding 503 amino acid residues (Mr = 56,880) and an unusually long 3'-untranslated region rich in AT sequence in the total length of 3,545 base pairs. The predicted amino acid sequence displays less than 30% similarity to other sequenced cytochrome P-450s indicating that the 7 alpha-hydroxylase constitutes a novel family of cytochrome P-450. The AT-rich region often contained ATTTA motifs, 5'-AAT-3' or 5'-TAA-3' trinucleotides which were reported to be involved in rapidly degrading mRNA. Employing the specific antibodies and the cDNA as probes, a diurnal variation of the levels of the three factors, i.e. enzyme protein, mRNA, and enzyme activity, was studied on rat livers prepared at various times of the day. In normal animals, all three factors exhibited maximum level at 10:00 p.m. and minimum at 10:00 a.m. No significant sexual difference was observed. Cholestyramine feeding increased all three factors at 10:00 a.m. close to the maximum levels of the normal rats, but did not show a significant increase at 10:00 p.m. On the contrary, starvation markedly decreased all three factors either at 10:00 a.m. or at 10:00 p.m., while maintaining still the diurnal variation. A good correlation of the levels of mRNA to the enzyme activities and the protein levels demonstrates that pretranslational regulation is most likely a mechanism for the circadian rhythm of 7 alpha-hydroxylase. The marked diurnal fluctuation of the amount of protein and the level of mRNA also indicates their rapid turnover. The short half-life of mRNA could be correlated with the structure of the 3'-untranslated region of the mRNA characteristic of rapidly degrading mRNA, i.e. abundance of motif, AUUUA, and existence of 5'-AAU-3' or 5'-UAA-3' trinucleotides in single-stranded regions of the secondary structure.

Amino Acid Sequence↗
PubMed1990

Molecular cloning of cDNA for vitamin D3 25-hydroxylase from rat liver mitochondria.

A cDNA clone encoding mitochondrial vitamin D3 25-hydroxylase was isolated from a rat liver cDNA library by the use of specific antibodies to the enzyme. The isolated cDNA clone was 1.9 kbp long and contained a 1599 bp open reading frame encoding 533 amino acid residues. The deduced primary structure contained a presequence typical for mitochondrial enzymes in the N-terminal region. The N-terminal sequence of the mature enzyme was determined to be Ala-Ile-Pro-Ala-Ala, which agrees perfectly with a portion of the deduced sequence, establishing the cleavage point of the precursor.

Amino Acid Sequence↗
PubMed1990

Membrane expression of decay-accelerating factor on neutrophils from normal individuals and patients with paroxysmal nocturnal hemoglobinuria.

Decay-accelerating factor (DAF), a complement-regulating glycoprotein, was found to be a maturational protein for normal neutrophils, and a remarkable correlation was found between the DAF level and alkaline phosphatase activity in neutrophils. We studied the relationship between the amount of DAF on the membrane and cell maturity in total nucleated bone marrow (BM) cells, mature BM and peripheral blood (PB) neutrophils from normal subjects, and patients with paroxysmal nocturnal hemoglobinuria (PNH) using a fluorescence-activated cell sorter with anti-DAF monoclonal antibodies. Percentage distributions of differentiating neutrophils from normal total nucleated BM cells showed that the proportion of immature cells (myeloblasts plus promyelocytes) decreased, while that of mature ones (bands plus segmented forms) increased as the fluorescence intensity increased. For PB neutrophils, no apparent correlation was found between DAF expression and cell maturity. This may have resulted from margination of the fully matured neutrophils with a high amount of DAF. In PNH patients who have low levels of DAF, this study showed that DAF expression in their neutrophils differs from that in normal subjects, and abnormalities occur in PNH cells from a very early stem-cell stage.

Alkaline Phosphatase↗
PubMed1990

Extrahepatic replication of duck hepatitis B virus: more than expected.

Replication of duck hepatitis B virus in extrahepatic tissue such as pancreas, kidney and spleen has been well documented. To assess whether there is more widespread extrahepatic virus replication, we assayed brain, heart, lung, thymus, pancreas, kidney, spleen and intestine of 1- to 16-wk-old ducklings for the presence of duck hepatitis B virus DNA and mRNA by blotting and in situ methods. Replicative intermediates and single-stranded duck hepatitis B virus DNA and RNA transcripts were detected in the brain, lung, heart, intestine, kidney, pancreas and spleen. In situ hybridization showed evidence of viral replication in the lung epithelium, germinal center of spleen, acinar cell of pancreas and tubular epithelium of kidney. These data suggest that extrahepatic duck hepatitis B virus replication is more widespread than previously thought. It is yet to be determined whether widespread extrahepatic replication is unique to duck hepatitis B virus infection or is a common feature of other mammalian hepatitis B-like viruses.

Animals↗
PubMed1990

Histological features and clinical course of large regenerative nodules: evaluation of their precancerous potentiality.

Seventeen patients with cirrhosis and histologically defined, ultrasonically detected, large regenerative nodules of the liver were followed without treatment for more than 1 yr (range = 13 to 51 mo). During the follow-up period, none of the nodules were demonstrated sonographically to have enlarged. Computed tomography and/or hepatic angiography were also performed in 14 patients, but there was no evidence of malignant transformation in these lesions. None of the 17 patients showed acute elevation of serum alpha-fetoprotein levels. Furthermore, four nodules became undetectable by these imaging procedures. Follow-up biopsy performed in seven patients revealed no significant histological changes from the first biopsy sample. However, HCCs developed apart from these large regenerative nodules in four patients. These HCCs suddenly appeared and did not seem to have been derived from preexisting large regenerative nodules. From these observations, it was not possible to regard a large regenerative nodule having no cytological atypia as a high-potential premalignant lesion. Their precancerous potentiality needs to be compared with that of ordinary pseudolobules.

Angiography↗
PubMed1990

Relative frequencies of portosystemic pathways and renal shunt formation through the "posterior" gastric vein: portographic study in 460 patients.

Percutaneous transhepatic portography was carried out in 460 patients with portal hypertension to study various collateral routes. Besides the left gastric vein, which was the most frequent collateral route and feeder of esophageal varices, a distinct vein located between the left gastric vein and the short gastric vein constituted a major collateral route in 191 patients (42%). In terms of frequency, this vein was more significant than the short gastric (34%) and the paraumbilical vein (24%) as a collateral route. We propose that this previously anonymous vein be called the "posterior gastric" vein because it runs posterior to the stomach. This vein also formed a renal shunt, a common cause of encephalopathy, in 43 (23%) of the 191 patients; the relative frequency of renal shunt formation by this vein was significantly greater than that by the left gastric vein (12%) and the short gastric vein (18%).

Collateral Circulation↗
PubMed1990

Automated measurement of trypsin inhibitor in urine with a centrifugal analyzer: comparison with other acute phase reactants.

Automated measurement of trypsin inhibitor in urine was performed with good precision using the COBAS FARA. Elevated levels of both trypsin inhibitor in urine and acute phase proteins in serum were shown in most cases of major abdominal surgery. We suggest that the automated assay of urinary trypsin inhibitor might be useful for the clinical diagnosis of acute phase response.

Acute-Phase Proteins↗
PubMed1990

Assessment of bull fertility using a mucus penetration test and a human chorionic gonadotrophin stimulation test.

The relative predictive abilities of an in vitro mucus penetration test and a human chorionic gonadotrophin (hCG) stimulation test were compared for assessing bull fertility. Cervical mucus was collected from 22 Holstein cows and then stored in liquid nitrogen. Semen was collected from 13 Holstein bulls and evaluated for standard semen parameters. The mucus penetration test was performed with fresh ejaculates, and the results were expressed as the distance traveled by the vanguard spermatozoa during incubation at 38 degrees C for 10 min. Increases in plasma testosterone levels were determined by a ratio of testosterone concentration before and after hCG injection. Sperm motility and mucus penetration were significantly correlated with the conception rate. However, no significant correlation was confirmed between the increased plasma testosterone levels and conception rate. The results indicate that the mucus penetration test is an effective method for predicting the fertility of bulls.

Journal Article↗
PubMed1990

Serum concentrations of the carboxyterminal cross-linking domain of procollagen type IV (NC1) and the aminoterminal propeptide of procollagen type III (PIIIP) in chronic liver disease.

Serum concentrations of both the carboxyterminal cross-linking domain (NC1) of procollagen type IV and the aminoterminal propeptide of procollagen type III (PIIIP) were measured by specific radioimmunoassays in 60 patients with chronic liver disease and 50 healthy controls. Compared with controls (5.3 +/- 1.3 ng/ml, mean +/- S.D.), NC1 concentrations were significantly elevated in patients with chronic active hepatitis (10.2 +/- 2.0 ng/ml) and liver cirrhosis (13.5 +/- 3.0 ng/ml), but not in chronic persistent hepatitis (6.0 +/- 0.9 ng/ml). The concentrations in patients with active liver cirrhosis were significantly higher than those in patients with inactive cirrhosis. Serum concentrations of PIIIP in controls, parients with chronic persistent hepatitis, chronic active hepatitis and cirrhosis were 5.8 (4.3-7.9), 5.3 (3.5-7.9), 17.5 (10.6-28.9), 16.7 (10.4-26.7) ng/ml, respectively (logarithmic mean and range of mean +/- S.D. after retransformation). Patients with liver cirrhosis had significantly higher concentrations of NC1 in serum than those with chronic active hepatitis, but there was no difference in serum PIIIP concentrations between the two groups. These data suggest an alteration of type IV collagen metabolism in chronic liver disease. In liver cirrhosis, the metabolism of collagen IV is apparently different from that of collagen type III; serum NC1 determinations may therefore provide additional information on chronic liver disease, particularly in patients with cirrhosis with a normal level of serum PIIIP. Further follow-up studies as well as investigations related to the basic mechanism of the elevation of these peptides in serum are needed in order to understand their clinical significance fully.

Chemical Phenomena↗