Search PubMed⌕ Search

Biomedical subjects

T Yasuda

Publications and source records attributed to T Yasuda.

At least 523 records · Page 29Linked to original sources
PubMed1993

D-lactate metabolism in patients with chronic renal failure undergoing CAPD.

To clarify the D-lactate metabolism in patients with chronic renal failure undergoing CAPD, plasma levels, loaded doses and urinary excretion of D-lactate were measured. In addition, D-2-hydroxy acid dehydrogenase activities in resected and autopsied specimens were measured. The daily loaded dose of D-lactate by CAPD was 88.9 +/- 1.29 mmol and urinary excretion was negligible. There was no tendency for the plasma D-lactate to accumulate. The enzyme activity was detected in the liver, kidney and pancreas tissues both in the resected and autopsied specimens. The above findings indicate that the loaded D-lactate is catabolized in patients with chronic renal failure undergoing CAPD, and D-2-hydroxy acid dehydrogenase is responsible for the metabolism of D-lactate in humans.

Adolescent↗
PubMed1993

A chimeric murine/human antibody Fab fragment directed against the platelet GPIIb/IIIa receptor enhances and sustains arterial thrombolysis with recombinant tissue-type plasminogen activator in baboons.

Inhibition of the platelet glycoprotein (GP) IIb/IIIa receptor with the murine monoclonal antibody 7E3 abolishes ex vivo platelet aggregation, reduces thrombogenicity, and sustains arterial recanalization with recombinant tissue-type plasminogen activator (rt-PA). A chimeric murine/human Fab fragment of 7E3 (c7E3-Fab) has a markedly reduced immunogenicity, but its potency as an adjunct for thrombolysis with rt-PA has not been evaluated. The effects of a single intravenous bolus injection of aspirin (17 mg/kg) or c7E3-Fab (0.45 mg/kg) on thrombolysis and reocclusion induced with rt-PA were studied in groups of six baboons with femoral arterial thrombosis and superimposed high-grade stenosis. This dose of c7E3-Fab blocked 96 +/- 1% of the platelet GPIIb/IIIa receptors and abolished ADP-induced platelet aggregation. Bolus intravenous injections of rt-PA (0.25 mg/kg) were repeated at 15-minute intervals until reperfusion occurred (maximum of four injections). In the aspirin group, reperfusion was obtained within 51 +/- 16 minutes (mean +/- SD) but was rapidly followed by reocclusion within 6 +/- 9 minutes and by cyclic reflow and reocclusion. In the c7E3-Fab group, reperfusion was obtained within 25 +/- 8 minutes (P < .01 versus aspirin group) and was associated with a delayed reocclusion of 63 +/- 63 minutes (P < .05 versus aspirin group). Template bleeding times remained unchanged in the aspirin/rt-PA group but were markedly prolonged (to > 30 minutes) in the c7E3-Fab/rt-PA group.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1993

Intravenous and endobronchial administration of G4120, a cyclic Arg-Gly-Asp-containing platelet GPIIb/IIIa receptor-blocking pentapeptide, enhances and sustains coronary arterial thrombolysis with rt-PA in a canine preparation.

G4120, L-cysteine, N-(mercaptoacetyl)-D-tyrosyl-L-arginylglycyl-L-alpha- aspartyl-cyclic(1-->5)-sulfide, 5-oxide, a synthetic cyclic Arg-Gly-Asp-containing pentapeptide, has a high affinity (dissociation constant of 4 nM) for the platelet glycoprotein (GP) IIb/IIIa receptor. The effects of its intravenous or endobronchial administration on thrombolysis, reocclusion, and bleeding time prolongation induced with 0.45 mg/kg bolus injections of recombinant tissue-type plasminogen activator in combination with intravenous heparin (4,000-unit bolus and 1,000 units each hour) were studied in a canine model consisting of an erythrocyte-rich blood clot in the left anterior descending coronary artery. Coronary patency was monitored for 3 hours both by ultrasonic flow probe and by repeat coronary angiography. Four groups of six to 10 dogs were studied with intravenous infusions of 0, 0.1, 0.2, or 0.3 mg/kg G4120 over 60 minutes. G4120 at a dose of 0.3 mg/kg reduced the time to reflow from a mean control value of 45 to 8 minutes (p = 0.036) and delayed reocclusion (p = 0.001). Four groups of five or six dogs were studied with endobronchial instillation of G4120 in a randomized, blinded study design using 0, 0.13, 0.25, or 0.5 mg/kg G4120. Endobronchial G4120 at a dose of 0.5 mg/kg reduced the time to reflow from a mean control value of 52 to 7 minutes (p = 0.039) and abolished cyclic reocclusion and reflow (p = 0.008). G4120 induced a dose-related transient prolongation of the template bleeding time and inhibition of ADP-induced platelet aggregation. G4120, a synthetic low-molecular-weight GPIIb/IIIa inhibitor that may be produced by chemical synthesis, may be of clinical value as a conjunctive agent for thrombolysis in patients with ischemic coronary syndromes.

Animals↗
PubMed1993

[A simultaneous determination of daidzin and puerarin and determination of daidzein in Oriental pharmaceutical decoctions containing puerariae radix by ion-pair high-performance liquid chromatography].

A simple and precise method was established for the simultaneous determination of daidzin and puerarin and the determination of daidzein in oriental pharmaceutical decoctions containing Puerariae Radix using high-performance liquid chromatography with tetra-n-heptylammonium bromide (THA) as an ion-pair reagent. Daidzin and puerarin were eluted within 45 min without interference with co-existing components using an ODS column and a mixture of 10 mM phosphate buffer (pH 6.5)-methanol (68:32) containing 5 mM THA as a mobile phase. Daidzein was eluted within 35 min without interference with co-existing components using an ODS column and a mixture of 10 mM phosphate buffer (pH 6.5)-acetonitrile (72:28 or 68:32) containing 5 mM THA as a mobile phase.

Chromatography, High Pressure Liquid↗
PubMed1993

[A simultaneous determination of honokiol and mangolol in Oriental pharmaceutical decoctions containing magnolia bark by ion-pair high-performance liquid chromatography. II].

A simple method using ion-pair high-performance liquid chromatography was established for the rapid and precise determination of honokiol(3',5-di-2-propenyl-1,1'-biphenyl-2,4'-diol) and magnolol(5,5'-di-2-propenyl-1,1'-biphenyl-2,2'-diol) in eighteen species of oriental pharmaceutical decoctions containing Magnolia bark. An ODS column and a mixed solvent system of water involving 10 mM tetra-n-amyl-ammonium bromide (TAA) and acetonitrile (4:6) as a mobile phase were used for the separation. Honokiol and magnolol were eluted without interference of other coexisting components within 12 min.

Biphenyl Compounds↗
PubMed1993

[Determination of synephrine in Oriental pharmaceutical decoctions containing aurantii nobilis pericarpium by ion-pair high-performance liquid chromatography. II].

A simple method using ion-pair high-performance liquid chromatography was established for the rapid and precise determination of synephrine in thirty three species of oriental pharmaceutical decoctions containing Aurantii Nobilis Pericarpium. An ODS column and a mixed solvent system of water, acetonitrile, sodium dodecyl sulfate and phosphoric acid as a mobile phase were used for the separation. Synephrine was eluted without interference of other coexisting components within 15 min.

Chromatography, High Pressure Liquid↗
PubMed1993

Inhibitory effects of insulin-like growth factor (IGF)-binding proteins-1 and -3 on IGF-activated glucose consumption in mouse BALB/c 3T3 fibroblasts.

We have examined the biological effects of insulin-like growth factor-binding proteins (IGFBPs) on insulin-like growth factor (IGF)-activated glucose consumption in a BALB/c 3T3 subline. The method employed was a colorimetric measurement of glucose consumption, allowing the detection of changes from the initial glucose concentration in conditioned medium, following the addition of IGFs and IGFBPs. Human IGFBP-1, purified from amniotic fluid, inhibited IGF-activated glucose consumption, although it had no effect on insulin-activated glucose consumption. The median effective dose (ED50) of IGFBP-1 to cause inhibitory effects on IGF-activated glucose consumption was 100-200 micrograms/l and was similar for both IGF-I and IGF-II at a concentration of 1.0 microgram IGF/l. Therefore, at IGF concentrations of comparable activity, the inhibitory effects of IGFBP-1 were greater for IGF-I than for IGF-II, because of the higher activity of IGF-I in this assay. Recombinant human IGFBP-3 also inhibited IGF-activated glucose consumption, without affecting insulin-stimulated glucose consumption. The inhibitory effects of IGFBP-3 were greater for IGF-II than for IGF-I when IGFBP-3 was coincubated with either of the IGFs, at both IGF concentrations of comparable activity and equivalent molar concentrations. Thus, it became clear that the inhibitory effects of these IGFBPs on IGF biological action depended primarily upon their affinity for the specific IGF ligand and molar ratio of IGFBP/IGF peptide. Interestingly, when cells were pretreated with IGFBP-3, prior to the simultaneous addition of IGFs and IGFBP-3, the inhibitory effect was higher for IGF-I than for IGF-II. Either no effect or a minor inhibitory effect on IGF-activated glucose consumption was detected with IGFBP pretreatment alone. When the ED50 for inhibition of IGF action by IGFBPs in this in-vitro assay was compared with the physiological concentrations of IGFs and IGFBPs in normal human serum and in amniotic fluid, it was estimated that the IGFBP-1 concentration present in serum was not sufficient to modulate IGF action effectively while the concentration in amniotic fluid was enough for effective suppression. IGFBP-3 exhibited an ED50 low enough to suppress IGF-II and possibly IGF-I action when cells were pretreated with IGFBP-3. Thus, our data suggested that IGFBP-1 in amniotic fluid and IGFBP-3 in serum could be a potent inhibitor for IGF action. IGFBP-1 in serum, however, may not be able to function as a direct inhibitor under physiological conditions but, rather, may modulate IGF action together with other IGFBPs.

Animals↗
PubMed1993

Sleep apnea and palatal myoclonus in a patient with neuro-Behçet syndrome.

A 50-year-old man with neuro-Behçet syndrome showed truncal imbalance, dementia, palatal myoclonus, snoring and rhythmic inspiration synchronized with palatal myoclonus. Magnetic resonance imaging showed hypertrophy of the bilateral inferior olivary nuclei with slight pontine atrophy. A polysomnographic recording disclosed sleep apnea during non-REM sleep: 6% central type, 46% mixed type, and 48% obstructive type. We speculate that lesions of the respiratory center or related structures in the brainstem resulted in sleep apnea and that laryngeal myoclonus also affected the apnea.

Behcet Syndrome↗
PubMed1993

Kidney diseases among the elderly--a clinicopathological analysis of 247 elderly patients.

We describe the clinicopathological features of 247 patients over the age of 60 with renal disorders. We acceded the histological classification of WHO recommendation, except for IgA nephropathy as primary glomerulonephritis. All nephrotic patients other than those with diabetic glomerulosclerosis (DGS) or amyloidosis were treated with steroids and/or immunosuppressants. Clinical data showed 88 patients with nephrotic syndrome. The histological study revealed that 142 patients had primary renal diseases and 105 patients had secondary renal diseases. Of 88 nephrotic patients, 35 were membranous nephropathy (MN) and 9 were minimal change nephrotic syndrome (MCNS). In secondary nephrosis, amyloidosis and DGS were diagnosed in 9 and 7 patients, respectively. A good response to therapy was obtained in MN (89%) and MCNS (78%). However, nephrotic patients with mesangial proliferative glomerulonephritis, amyloidosis, or DGS had unfavorable outcomes. Histological observations are useful aids in estimating the prognosis and therapy selection for renal disorders even in elderly patients.

Age Factors↗
PubMed1993

Immune complex type crescentic glomerulonephritis accompanied with perinuclear anti-neutrophil cytoplasmic antibodies.

A 70-year-old male developed rapidly progressive glomerulonephritis syndrome with serum perinuclear anti-neutrophil cytoplasmic antibodies (P-ANCA). A renal biopsy showed diffuse crescentic glomerulonephritis. Immunofluorescence microscopy revealed 2+ granular staining of IgG over the mesangial area and along glomerular capillary walls. Electron microscopy showed scattered deposits in the paramesangial area. These morphologic findings were consistent with those of immune complex type crescentic glomerulonephritis (IC-CGN). Serum C3, C4, and CH50 were within normal limits, and circulating immune complexes were not detected by C1q-binding assay, but both P-ANCA and anti-myeloperoxidase antibodies were positive. A possible relation of P-ANCA to IC-CGN is discussed.

Aged↗
PubMed1993

Tautomeric phenomenon of a novel potent immunosuppressant (FK506) in solution. I. Isolation and structure determination of tautomeric compounds.

Tautomeric phenomenon was observed in the HPLC chromatogram obtained from a novel potent immunosuppressant, FK506, in ethanol solution. Two tautomeric compounds derived from FK506 were isolated and purified by HPLC. Their structures were elucidated by spectral analyses. The mechanisms for this tautomerization were also established based on the results of structure analysis.

Isomerism↗
PubMed1993

An abdominal wall-lift method of laparoscopic cholecystectomy without peritoneal insufflation.

Laparoscopic cholecystectomy is unusually performed with peritoneal insufflation of carbon dioxide gas, which limits the free use of conventional surgical techniques and is accompanied by operative risks resulting from trocar insertion, hypercapnia, and increased intraabdominal pressure. We have improved the laparoscopic cholecystectomy procedure by using an abdominal wall-lift technique that does not utilize peritoneal insufflation. The operative field is almost the same as in the pneumoperitoneum method with the exception of morbidly obese patients. Because airtightness between manipulating instruments and the abdominal wall is not required, we are able to use conventional surgical instruments and techniques in addition to those specifically designed for laparoscopic surgery. The abdominal wall-lift method enables us to perform laparoscopic surgery with greater ease than the pneumoperitoneum method. It can also be extended to other kinds of abdominal surgery in addition to cholecystectomy.

Abdominal Muscles↗
PubMed1993

Increase in cell responses and protein phosphorylation of neutrophils induced by synthetic diacylglycerols.

Diacylglycerols (DG) induced various stimulation-coupled responses of guinea pig peritoneal neutrophils (GPPMN), such as superoxide (O2-.) generation, luminol chemiluminescence response (LCL) and membrane depolarization. These activities induced by L-alpha-1,2-dioctanoyl glycerol (diC8) are quite similar to those induced by phorbol 12-myristate 13-acetate (PMA). The effects of diC8 were much stronger than those of L-alpha-1-oleoyl-2-acetylglycerol (OAG) and no effect was produced by L-alpha-1,2-dioleoyl glycerol (DO). Concentrations of diC8 and OAG for maximal O2-. generation were 1 and 10 microM, respectively. However, rat brain Ca(2+)- and phospholipid-dependent protein kinase (PKC) was activated by all DGs used, and the concentrations of OAG, DO and diC8 for half maximum stimulation were 0.2, 1.0 and 2.0 microM, respectively. Discrepancies between the concentrations of DGs required for O2-. release and PKC activation might be due to differences in their affinity for and permeability in the membrane. The generation of active oxygen and the PKC activity were both sensitive to PKC inhibitors, such as 1-(5-isoquinolinesulfonyl)-2-methyl-piperazine (H-7) and staurosporine. ID50 of H-7 and staurosporine for the inhibition of diC8-induced O2-. release were 150 nM and 10 nM, respectively. By contrast, staurosporine does not inhibit diC8 induced membrane depolarization. Phosphorylation of cytoplasmic proteins, such as the 47 kDa protein, was increased by DGs and this phosphorylation was also inhibited by H-7 or staurosporine. The capacities of stimulating the rates of 47 kDa protein phosphorylation were in the order diC8 > OAG > DO. These results suggest the involvement of protein phosphorylation in DG-induced O2-. generation. However, a part of the O2-. generation induced by high concentration of DG might have occurred via a PKC-independent pathway.

1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine↗
PubMed1993

Deoxyribonuclease I (DNase I) typing from semen stains: low enzyme activity in vaginal fluids does not interfere with seminal DNase I typing from mixture stains.

We describe the use of deoxyribonuclease I (DNase I) polymorphism for individualization of semen in body fluid stain mixtures, as a means of providing new and more useful information to practicing forensic biologists as a genetic marker. We have already reported that human DNase I isozyme patterns from different subjects are classifiable into ten groups. Isoelectric focusing of DNase I isozymes on polyacrylamide gel (IEF-PAGE, pH 3.5 to 5) was accomplished using a 0.5 mm thick gel. Pretreatment of semen samples with neuraminidase enhanced the isozyme band resolution and sensitivity. Activity detection using the dried agarose film overlay (DAFO) procedure was reliable, sensitive and simple, with high resolution, and the phenotypes of DNase I were determined in semen stains of about 0.3 microL stored at room temperature for up to a year in most of the samples tested. The DNase I types in semen stains were correlated with the types found in the corresponding blood and urine samples, although most of the vaginal fluid samples had no typable DNase I activity. This is considerably advantageous for seminal individualization from body fluid mixture stains in criminal cases. An evaluation of DNase I typing by IEF-PAGE and DAFO was also performed on casework samples submitted to our laboratory, and the results showed that DNase I was expected to be one of the most useful individualization marker of semen in practical application.

Body Fluids↗
PubMed1993

[Clinical diagnosis of movement disorders--evoked potentials].

As a clinical diagnostic approach, the evoked potential has been used to differentiate movement disorders, especially myoclonic movements, Giant somatosensory evoked potentials (SEPs) and long-loop reflex to electrical stimulation of the peripheral nerve are commonly employed in the evaluation of patients with myoclonus. Recently, abnormality in a specific component of SEP frontal N30 has been reported in focal dystonia. Jerk locked back averaging has been applied to cortical reflex myoclonus, minipolymyoclonus, cortical tremor, simple tics, chorea-acanthocytosis, Huntington's chorea, etc. Silent period locked averaging is also used for asterixis. With these new electrophysiological techniques, evaluation of functional mechanisms in movement disorders may be expected, with fruitful results.

Diagnosis, Differential↗
PubMed1993

Inhibitory effects of cholera toxin on in vitro growth of human lung cancer cell lines.

Cholera toxin (CT) inhibited the growth of three out of 10 small cell lung cancer (SCLC) cell lines and two out of seven non-small cell lung cancer (NSCLC) cell lines when tested by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay. These CT-sensitive as well as CT-resistant cell lines bound well to the non-toxic CT-B subunit-fluorescein isothiocyanate conjugate (FITC-CTB) when assayed by flow cytometry. Using the reaction of horseradish peroxidase-conjugated CT-B (HRP-CTB) on thin-layer chromatography (TLC), we analyzed gangliosides extracted from SCLC cell lines, CT-resistant SBC-1, minimally CT-sensitive SBC-3 and CT-sensitive SBC-5. HRP-CTB was found to react not only with GM1, but also with Fuc-GM1, GD1b and other gangliosides on TLC. Although CT-resistant SBC-1 cells bound well to FITC-CTB, the binding of gangliosides extracted from SBC-1 cells to HRP-CTB was markedly decreased when compared to those from CT-sensitive SBC-5 cells. The CT resistance of the minimally CT-sensitive SBC-3 cell lines, which binds weakly FITC-CTB and HRP-CTB, was partially reversed by exogenous GM1 pretreatment. These observations suggest that the amount of gangliosides, such as GM1, Fuc-GM1 and GD1b, on the cells, rather than the CT-binding ability to the cells, plays a major role in cytotoxicity by CT.

Carcinoma, Non-Small-Cell Lung↗
PubMed1993

The antiseptic effect of a quick drying rubbing type povidone-iodine alcoholic disinfectant solution.

A quick drying rubbing type disinfectant of non-water non-towel type is an antiseptic method suitable for practical use in intensive care units where emergency situations are common. We determined the antiseptic efficacy and safety of a quick drying rubbing type povidone-iodine alcoholic disinfectant solution (HAD Hand Wash) in comparison with benzalkonium chloride alcoholic lotion. The bacterial reduction rate obtained by hand washing with a single 3 ml application was 93.8% for HAD Hand Wash and 94.1% for benzalkonium chloride alcoholic lotion. Thus, excellent antiseptic efficacy was obtained with both disinfectants. Roughening of hand skin which appeared in association with HAD Hand Wash solution was transient and mild in nature in all of the cases, indicating the high safety of this disinfectant. It is justified to say from these findings that HAD Hand Wash is useful as a hand and finger disinfectant.

Antisepsis↗