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Biomedical subjects

K Okuda

Publications and source records attributed to K Okuda.

At least 505 records · Page 28Linked to original sources
PubMed1992

Monoclonal antibody to human plasma gelsolin.

Human plasma gelsolin was purified by column chromatography. The method yielded a protein of high purity and activity. Using this protein, we produced monoclonal antibody (Mab H6B11) against human plasma gelsolin by somatic cell fusion. This monoclonal antibody reacted in a dose-dependent manner with gelsolin derived from human plasma and platelets and neutralized depolymerizing activity to F-actin. It differed from the commercially available substance (Mab G4896; Sigma) in that the time required for the reaction between the antigen and antibody in the enzyme-linked immunosorbent assay could be shortened by one-third. The antibody was judged to be useful in assays for elucidating the physiological role of plasma gelsolin.

Animals↗
PubMed1992

[Clinical effects of six-month short time biofiltration].

The clinical effects of six-month short time biofiltration (SBF) were evaluated using a B-A-B' study (B, B': conventional bicarbonate hemodialysis; CBHD, A:SBF) in ten patients maintained on CBHD three times a week. An F80 hemodiafilter (1.9 m2, polysulfone, Fresenius) was used. In addition to routine clinical parameters for a patient on regular dialysis treatment, plasma von Willebrand factor antigen (vWF) (an index of stimulation of vascular endothelium), and the methylguanidine/creatinine ratio (MG/Cr) and malondialdehide (MDA) (indices of the levels of oxygen radicals), were evaluated. Nine patients completed the study, one patient dropping out at the 12th week of A because of muscle cramps during SBF. The treatment time was 2 hours in six cases and 2.5 hours in three cases. The mean blood flow rate was 280 +/- 42 (SD) minutes. Using the urea kinetics model, the mean KT/V was 1.26 +/- 0.28, and the mean protein catabolic rate was 1.22 +/- 0.18 g/kg body weight/day at the end of A. No change in ultrafiltration, blood pressure, cardiac function (assessed by echocardiography), CTR, human atrial natriuretic peptide, total protein, albumin, uric acid, serum creatinine, sodium, calcium, inorganic phosphorus, vWF, or MDA was found between each period. Blood urea nitrogen, c-PTH, and MG/Cr increased during the A period. Serum magnesium and beta-2 microglobulin decreased during the A period. Blood gas results, on the whole, did not change. In a patients, however, acidosis gradually developed. An increase in substitution fluid from 5 L/session to 7.5 L/session improved the acid-base balance in that patient. In conclusion, SBF is as effective as CBHD in removing small molecules and maintaining cardiocirculatory status, and is superior to CBHD in removing beta 2-microglobulin and is less stimulative to the endothelium than CBHD.

Adult↗
PubMed1992

[Historical aspects of clinical enzymology].

The field of clinical enzymology has markedly progressed in recent years. Diagnostic enzymology, therapeutic enzymology and enzymes as analytical reagents continue to contribute to the progress of health care. However, there are many aspects of the historical changes that have taken place in this field that are surprisingly unknown. The presentation I am about to give attempts to provide an overview of the history of the development of clinical enzymology and clinical chemistry. I hope it will be of reference to you.

Chemistry, Clinical↗
PubMed1992

[A device for hepatic arterial catheterization using saphenous vein graft].

We performed regional arterial infusion chemotherapy for hepatocellular carcinoma by retaining a hepatic arterial reservoir. The catheters were placed via gastroduodenal artery and positioned at the junction with common hepatic artery during operation. But we encountered many complications and did not perform regional arterial infusion chemotherapy. This time we cannulated through the saphenous vein graft by which hepatic perfusion was maintained by the superior mesenteric artery; we did not cannulate through the common femoral artery using a subcutaneously implanted reservoir. Venous arterial anastomosis is performed with interrupted (7-0 Prolene) vascular suture. Postoperative angiography by the reservoir showed total hepatic perfusion. There have been no instances of hemorrhage, thrombosis, or catheter dislodgement with this technique. Duration of follow-up varied from 2 to 7 months.

Carcinoma, Hepatocellular↗
PubMed1992

The relationship between polysaccharide antigen and interleukin-1 beta producing activity in Porphyromonas gingivalis.

Strains of Porphyromonas gingivalis were serologically classified into three groups (a, b, and c) by immunodiffusion test using the autoclave extracted antigens. All tested strains had proteolytic activity, but the activity differed from strain to strain, regardless of serogroup. It was found that serogroup a strains had more collagenolytic activity than did serogroup b (p < 0.05), but that the three groups have no remarkable differences in trypsin activity. All autoclave extracted serogroup-specific antigens induced the release of interleukin-1 beta (IL-1 beta) from human peripheral monocytes. Serogroup-specific antigen of an invasive strain designated 16-1 (serogroup b) induced the highest release of IL-1 beta among all samples. The results of immunoblotting tests and IL-1 beta production indicated that there are serogroup-specific polysaccharide other than lipopolysaccharide in P. gingivalis.

Antigens, Bacterial↗
PubMed1992

Corroding characteristics of Eikenella corrodens.

Fourteen strains of Eikenella corrodens isolated from human oral cavity were studied to determine corroding characteristics. Nine out of the 14 strains produced corroding colonies under anaerobic culture condition. One of them produced corrosion even in an aerobic culture. No morphological differences in surface structures were observed between corroding and non-corroding strains of E. corrodens by transmission electron microscopy. The morphology of corroding colonies of E. corrodens was then examined by scanning electron microscopy. The surface of the corroding-colony center was smoothly convex. A boundary line was clear between the smooth center and the surrounding corrosion region. Double or triple frill-like structures surrounded the center portion with small convexities. Spreading bacterial masses were observed in the outer portion of the colony. Morphological observations of the corroding colony edge indicated that a surface translocation termed "twitching motility" or "gliding motility" occurs in the outer portion and plays a role in its colonization of periodontal regions.

Bacterial Adhesion↗
PubMed1992

Effects of cobalamin, cobalamin analogues and cobalamin binding proteins on P388D1 mouse leukemic cells in culture.

Cobalamin-deficient P388D1 mouse leukemic cells were created by propagation in a cyanocobalamin-free medium in which the original fetal bovine serum was replaced by bovine serum albumin. These cobalamin-deficient cells gradually ceased to multiply when the medium contained 5-methyltetrahydrofolate. The growth of cells that had been cultured with this coenzyme was recovered following the addition of cyanocobalamin (CNCbl), at concentrations above 37 pM. In contrast to the effect of CNCbl, cobinamide, and cobalamin analogues prepared from hydroxy cobalamin by reaction with ascorbic acid, did not have a growth-inducing effect on these cells, nor did these analogues inhibit CNCbl-dependent growth. Transcobalamin II-cobalamin complex had a remarkably stimulating effect on cell growth. The growth inducing effect became apparent with a cobalamin concentration of only 0.37 pM. This was about 1/100th the level of free cobalamin required for cell growth. However, no growth-inducing effect was seen at an R protein-bound cobalamin concentration of 37 pM, indicating that once cobalamin has been bound to R protein, it loses its growth-promoting effect on these cells in culture.

Animals↗
PubMed1992

[Development of automated lactate analyzer with continuous blood sampling for monitoring blood lactate and its application for the testing of physical exercise].

The anaerobic threshold is useful for estimating the intensity of physical exercise. It is shown as either an increase in blood concentrations of lactate or a disproportionate increase in ventilation. We developed a lactate analyzer based on an electroenzymatic method with a continuous blood sampling system through a double-lumen catheter. Ascorbic acid, bilirubin, hemoglobin, creatinine, uric acid, and glucose did not interfere the results. The lactate concentrations in blood samples from healthy subjects during physical exercise correlated well (r = 0.993) with results measured by the conventional enzymatic method. We measured the concentrations of blood lactate with a use of this lactate analyzer to see the anaerobic threshold in nine healthy volunteers during exercise on a treadmill with an increasing workload. The point at which lactate concentrations started to increase was detected easily. The anaerobic threshold identified as a disproportionate increase in ventilation was seen at almost the same time. We conclude that the lactate analyzer, with a continuous blood sampling system, can measure precisely concentrations of lactate in blood and can detect the anaerobic threshold during physical exercise.

Adult↗
PubMed1992

Danazol therapy in idiopathic thrombocytopenic purpura: the efficacy of low-medium dose therapy.

To examine the effects and optimal dose of danazol on idiopathic thrombocytopenic purpura (ITP), we administered a low-medium dose to 14 patients with this disease. A low-medium dose of danazol was effective in maintaining the platelet count at a high level, even after the dose of prednisolone was reduced. A low-medium dose of danazol without other therapy was effective in 3 of 6 patients even after they had been refractory to other treatment. A low dose of danazol was also effective in some patients for whom the other regimes were not indicated. It is concluded that a low-medium dose of danazol instead of a high dose is worth trying in ITP when the patient has become refractory to other therapeutic approaches or when these are not indicated.

Adult↗
PubMed1992

[An epidemiological study of methicillin-resistant Staphylococcus aureus (MRSA) isolated from medical staffs, inpatients and hospital environments at our hospital].

Methicillin-resistant Staphylococcus aureus (MRSA) is one of the most important microorganisms which is causative of the nosocomial infections. Recently the incidence of isolation of MRSA is increasing from year to year in Japan. Especially MRSA isolated from inpatients are much higher than from outpatients. Therefore we have done epidemiological studies about MRSA isolated from medical staffs, inpatients and hospital environments in our hospital. Thereafter we examined phage typing and coagulase typing of those MRSA. MRSA were isolated more frequently from anterior nares of inpatients in compare with doctors and nurses. MRSA were isolated more frequently from the environments of MRSA carriers. Coagulase type II and phage type N.T. (not typable) were dominant type of MRSA in our hospital (69% and 61%). Our studies have revealed that the isolation frequency of MRSA is very high in our hospital. It seems to suggest that inpatients who are carrying MRSA are spreading MRSA out hospital environments and medical staffs.

Cross Infection↗
PubMed1992

[Urinary trypsin inhibitor as an acute phase reactant].

Early in this century, trypsin inhibiting activity has already been recognized in patients with acute infection or renal disease. In addition to these, conditions such as coronary thrombosis, surgical operation, artificial fever by heat-killed bacilli, malignancy, leukemia, later stage of normal pregnancy, etc. have been known to cause the elevated excretion of UTI in urine. Typically, maximal excretion of UTI has been observed within one or two days after the onset. It appears that recent studies have overcome the complexity of UTI molecule. Automated measurement of urinary trypsin inhibitor (UTI) in urine sample was carried out by either enzymic or immunologic method. UTI as well as erythrocyte sedimentation rate and C-reactive protein enables us to monitor acute phase response, being confirmed in cases of abdominal surgery.

Abdomen↗
PubMed1992

Angiography in portal hypertension.

In this article, various angiographic techniques that may be useful in the assessment of portal hemodynamics are described with illustrative angiograms, providing examples of celiac arteriography; arterial venography; transsplenic, umbilical, operative, and transhepatic portography; hepatic venography; and other techniques. When they are combined with other imaging modalities, the information gained increases. Interventional and therapeutic angiography, such as angiographic occlusion of a large shunt causing encephalopathy or of an arterioportal shunt, widening of a narrowed shunt, and perforation of membranous obstruction of the inferior vena cava, is discussed.

Catheterization↗
PubMed1992

[MELAS associated with diabetes mellitus and point mutation in mitochondrial DNA].

Point mutation of mitochondrial DNA has been described in the blood from a MELAS patient. The 39-year-old patient developed progressive dementia, stroke-like episodes, heart conduction defect (Lown-Ganong-Levin syndrome) and cortical blindness. CT scan revealed brain atrophy and low density areas in the bilateral occipital lobes. Laboratory tests showed hyperglycemia and lactic acidosis. Muscle biopsy showed ragged red fibers on Gomori trichrome staining. He was clinically diagnosed as having MELAS and insulin-dependent diabetes mellitus. Onset of diabetes mellitus and MELAS was almost same. Family history showed his mother's brother and sisters had also insulin-dependent diabetes mellitus. We amplified the leucine (UUR) tRNA gene from the patient's blood with polymerase chain reaction (PCR) and analysed it by restriction enzyme analysis and sequencing. Genetic analysis showed A-to-G substitution at the nucleotide position 3243 in the leucine (UUR) tRNA gene. This substitution made a new restriction site Apa I. Mutant DNA coexisted with wild type DNA (heteroplasmy). It is shown that in some types of mitochondrial encephalomyopathies, especially patients of Kearns-Sayre syndrome (KSS), diabetes mellitus is often complicated. And in KSS patients insulin receptor in normal, but insulin secretion from beta cells of pancreas is decreased. In MELAS patients, however, has diabetes mellitus been reported to be rarely complicated and relationship between MELAS and diabetes mellitus is not done. As far as we know, two cases, including ours, with genetically diagnosed MELAS have been reported to have diabetes mellitus.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

Functional expression of the alpha 1 subunit of the AMPA-selective glutamate receptor channel, using a baculovirus system.

Using a baculovirus expression vector system, the alpha 1 subunit of the mouse AMPA (alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionate)-selective glutamate receptor channel was expressed in insect Spdoptera frugiperda cells. Binding studies using [3H]AMPA showed that insect cells infected with the recombinant virus expressed approximately 1.8 x 10(5) binding sites per cell on their surface. The ligand binding characteristics of the receptors expressed in insect cells were examined. The baculovirus-insect cell expression system affords high-efficiency expression of the receptor in sufficient amounts to permit structural and functional analyses.

Animals↗