Biomedical subjects

T Yasuda

Publications and source records attributed to T Yasuda.

At least 559 records · Page 31Linked to original sources

PubMed1992

Human urine deoxyribonuclease II (DNase II) isoenzymes: a novel immunoaffinity purification, biochemical multiplicity, genetic heterogeneity and broad distribution among tissues and body fluids.

Deoxyribonuclease II (DNase II) was purified from the urine of a 48-year-old male (a single individual) using a column chromatography series, including concanavalin A-agarose and an immunoaffinity column utilizing anti-human spleen DNase II antibody, and was then characterized. Based on the catalytic properties of the purified enzyme, we have devised a technique of isoelectric focusing by thin-layer polyacrylamide gel electrophoresis (IEF-PAGE) combined with a specific zymogram method, for investigating the possible molecular heterogeneity of human DNase II. DNase II in urine as well as the purified form was found to exist in multiple forms with different pI values separable by IEF-PAGE within a pH range of 5-7. Since sialidase treatment of the urine sample induced simplification of the isoenzyme patterns with diminishment of anodal bands, it was clear that the multiplicity of the enzyme was in part due to differences in the sialic acid content. On screening of DNase II isoenzyme patterns in urine samples from more than 200 Japanese individuals, only the common isoenzyme pattern was observed and no electrophoretic variations were detected. However, genetic studies of urinary enzyme activity and comparative studies on the activity in urine, semen and leukocytes from the same individuals suggest that the enzyme activity level of DNase II may be under genetic control. The enzyme was widely distributed in human tissues and showed high activities in secretory body fluids such as breast milk, saliva, semen and urine, and leukocyte lysates.

Body Fluids↗

PubMed1992

Fluorescence quenching measurements of the membrane bound lipid haptens with different length spacers.

Dansyl lipid haptens with three different length (short, intermediate and long) spacers have been incorporated into DMPC or DPPC liposomes. Anti-DNS-IgG bound most efficiently to these liposomes containing lipid haptens with an intermediate length spacer, although the binding efficiency became more increased when liposomes were made of a mixture of phospholipid (DMPC or DPPC) and cholesterol. To explain these results we have measured the accessibility of dansyl lipid haptens in liposomal membranes by the fluorescence quenching method. It was found that the dansyl haptens located on the surfaces of DMPC (or DPPC) membranes and fluorescence quenchers (iodide ions) possessed almost similar accessibility for the dansyl haptens with different length spacers. However, in the DMPC (or DPPC) membranes with 50% cholesterol, a part of the dansyl haptens became buried into the interior of the liposomal membranes depending on the length of the spacer and another part removed into the aqueous solution with greater affinity for antibody. These results were explained well by our recent model for antibody binding to the membrane-bound lipid haptens.

1,2-Dipalmitoylphosphatidylcholine↗

PubMed1992

Severity of X-linked recessive bulbospinal neuronopathy correlates with size of the tandem CAG repeat in androgen receptor gene.

The genetic mutation of X-linked recessive bulbospinal neuronopathy is amplification of a polymorphic tandem CAG repeat in the androgen receptor gene. We studied this CAG repeat in 26 Japanese patients from 21 families with X-linked recessive bulbospinal neuronopathy. The number of CAG repeats was significantly correlated with the age at onset of limb muscular weakness (r = -0.596, p < 0.001) and age-adjusted scored disability (r = 0.446, p < 0.03). The length of the CAG repeat therefore seems to be a determinant factor of clinical severity.

Adult↗

PubMed1992

Discovery of a genetic polymorphism of human plasma protein C inhibitor (PCI): genetic survey utilizing isoelectric focusing followed by immunoblotting, immunological and biochemical characterization.

The objectives of this study were to determine the genetic basis of the electrophoretic differences of human plasma protein C inhibitors (PCI) from 977 individuals. Three discrete antibodies were produced against the PCI purified from human plasma and peptides that corresponded to the N-terminal 15 amino acid residues and the C-terminal 15 residues of human PCI, the chemical structures of which were determined by cDNA sequence analysis. The combined techniques of polyacrylamide gel isoelectric focusing and immunoblotting with these three different antibodies resolved the plasma PCI into several isoprotein bands, with a pH range of 6-7. These PCI isoproteins, however, were not stained by anti-human kallikrein, anti-human protein C or anti-human urokinase antibodies. Therefore, each of the PCI bands, which were detected by immunoblotting with the anti-PCI antibody and the two different anti-peptide antibodies, were derived from free PCI, and not an inactive PCI species. Two common phenotypes, designated PCI 1 and 1-2, were recognized, and family studies showed that they represented homozygosity or heterozygosity for two autosomal codominant alleles, PCI*1 and PCI*2. A population study of plasma samples collected from 977 Japanese individuals indicated that the frequencies of the PCI*1 and PCI*2 alleles were 0.988 and 0.012, respectively.

Alleles↗

PubMed1992

Significance of fibrils in the formation of the Kimmelstiel-Wilson nodule.

The pathogenesis of the nodular lesion in diabetic glomerulosclerosis is described in association with fibrils. Thirteen diabetic patients with glomerular nodular lesions and 9 diabetics without the nodules were examined by electron microscopy using periodic acid-thiocarbohydrazide-silver proteinate staining. In cases of nodular glomerulosclerosis, abundant fibrillar structures mixed with electron-dense material were detected within the nodule and the mesangial matrix. They were also occasionally observed along the subendothelial space of the glomerular capillary walls. On the cross-section, these fibrils, including the lucent periphery, were 34 nm wide. Immunohistologically, collagen V and collagen VI were detected in nodular lesions. In contrast, in cases of the diffuse type of glomerulosclerosis, the widened mesangium was composed of dense material, which resembled the original mesangial matrix. The above fibrils were not detected in the mesangium. These findings suggest that the accumulation of the peculiar fibrils in the glomerular mesangium is a major pathogenic factor in the formation of Kimmelstiel-Wilson nodules.

Adult↗

PubMed1992

Radical laser segmentectomy for T1 N0 lung cancer.

Over the last 40 months, 18 lung cancer patients with T1 N0 non-small cell lung carcinoma have been treated with radical laser segmentectomy. This innovative operative method consists of a combination of anatomical or nonanatomical segmentectomy by neodymium:yttrium-aluminum garnet laser parenchyma sparing with complete hilar lymph node dissection. Although the median follow-up period is too short, there is no local recurrence and no cancer deaths. There have been no major complications. Even deep-seated tumors can be resected with a clear safety margin using this method. Radical laser segmentectomy may be a useful adjunct to preserve normal lung tissue and to perform very radical resection.

Aged↗

PubMed1992

A new individualization marker of semen: deoxyribonuclease I (DNase I) polymorphism.

We describe a method for obtaining specific and reproducible deoxyribonuclease I (DNase I) typing from liquid semen. Isoelectric focusing of the enzymes on polyacrylamide gel (IEF-PAGE, pH 3.5-5) was accomplished using a 0.5-mm thick gel. The separated isozymes were visualized by a new activity staining method, dried agarose film-overlay (DAFO). Pretreatment of semen samples with neuraminidase markedly enhanced the isozyme-band resolution and sensitivity. The method was simple and reliable, with high resolution and sensitivity. The DNase I types in semen samples were correlated with the types found in corresponding blood and urine samples. DNase I typing could therefore provide an additional discriminant characteristic in the forensic examination of semen.

Deoxyribonuclease I↗

PubMed1992

Circulating interleukin 6 as a useful marker for predicting postoperative complications.

We examined postoperative serial changes in the levels of serum interleukin 6 (IL-6), serum acute phase reactants (APRs) and plasma neutrophil elastase (NE) in patients with various cancers and reviewed these changes in patients who did, and did not, show postoperative complications. Serum IL-6 level was elevated after surgery, peaking on the first postoperative day. Elevation of serum APRs and plasma NE levels also followed. There was a significant correlation between the serum peak level of IL-6 and those of APRs and NE (P less than 0.01). Moreover, there was a significant difference in the serum IL-6 level in patients with and without complications. The relationship between the serum IL-6 greater than 400 pg/ml and the incidence of postoperative complications was also marked. These results suggest that circulating IL-6 is a clinically useful marker for the earliest detection and prediction of postoperative complications.

Adult↗

PubMed1992

The zymogram method for detection of ribonucleases after isoelectric focusing: analysis of multiple forms of human, bovine, and microbial enzymes.

A zymogram method for detection of in situ ribonuclease (RNase) activity, combined with isoelectric focusing in a thin layer of polyacrylamide gel (IEF-PAGE), has been developed. After incubation with a dried agarose film containing substrate RNA, ethidium bromide, and an appropriate reaction buffer, which was placed tightly on the top of the focused gel, sharp and distinct dark bands corresponding to RNase isoenzymes on a fluorescent background appeared under uv light. Addition of urea to the IEF-PAGE gel at a final concentration of 4.8 M permitted optimal focusing of the RNases. This method had not only a high sensitivity of less than 0.1 ng purified RNase A, but also a high band resolution compared with the immunostaining method. It was also useful for analysis of purified enzymes, including bovine pancreatic RNases and two types of human urine RNase as mammalian enzymes, and RNases T1 and T2 as microbial enzymes, as well as for detection of RNases present in crude tissue extracts, resulting in more detailed elucidation of the multiplicity of these enzymes.

Acrylic Resins↗

PubMed1992

Kinetic study of the transformation from tetrahydrate to monohydrate of a new antiallergic, sodium 5-(4-oxo-phenoxy-4H-quinolizine-3-carboxamide)-tetrazolate.

Two hydrates (tetrahydrate, I, and monohydrate, II) of a new antiallergic, sodium 5-(4-oxo-phenoxy-4H-quinolizine-3-carboxamide)-tetrazolate (FR71021), were prepared and characterized by means of infrared spectrometry, thermal analysis, and power X-ray diffraction spectrometry. While I was confirmed to dehydrate readily resulting in an anhydrate form (noncrystalline form) below its critical relative humidity for dehydration, I was also transformed into II under humid conditions. The transformation kinetics from I to II were investigated under varying temperature and humidity conditions by a powder X-ray diffraction technique. The transformation mechanism followed a zero-order reaction, and the apparent transformation rate constant (k) could be described as a function of water vapor pressure (P), temperature (T), and the interaction orders between water vapor pressure and the samples (s): k = A.exp(-Ea/RT).Ps, where Ea is the activation energy and R is the gas constant.

Biotransformation↗

PubMed1992

Growth hormone-binding protein in patients with anorexia nervosa determined in two assay systems.

To learn the mechanism of low plasma insulin-like growth factor-I (IGF-I) despite high growth hormone (GH) secretion in patients with anorexia nervosa, we assessed human serum GH-binding protein (BP) (GH-BP), which has been shown to be identical to the extracellular domain of GH receptor, and therefore might reflect peripheral GH receptor expression (i.e. there is a significant linear correlation between GH-BP and IGF-I at less than 2.0 U/ml in healthy children). The serum GH-BP level was determined by gel filtration and confirmed by immunoassay using GH receptor monoclonal antibody. Furthermore, we analyzed serum IGF-binding proteins (IGFBPs) by the affinity cross-linking method to determine the GH-IGF-I axis in this condition. Measurement of GH-BP by the two assays gave identical results, suggesting that serum GH-BP corresponds to the extracellular domain of GH receptor. The low GH-BP and high IGFBP levels in patients with anorexia nervosa shown in this study, which were normalized by an improved nutritional state, would indicate resistance to GH as well as to IGFs in this condition, in which the former is in part compensated by high GH levels while the latter is not.

Adolescent↗

PubMed1992

1H-NMR assignment and secondary structure of human insulin-like growth factor-I (IGF-I) in solution.

Human insulin-like growth factor-I (IGF-I) was studied by two-dimensional 1H-NMR spectroscopy. Resonance assignments were obtained for all the backbone protons and almost all of the sidechain protons of the total 70 amino acid residues, using sequence-specific assignment procedures. The secondary structure elements of human IGF-I were identified by investigation of the sequential and medium range NOEs as a preliminary step in determining the three-dimensional structure of this protein by means of distance geometry calculations. The typical NOEs of d alpha beta(i,i + 3) and d alpha N(i,i + 3), as well as the successive strong NOEs of dNN connectivities and slowly exchanging amide protons confirmed the presence of three helical segments corresponding to the sequence regions, Ala8-Cys18, Gly42-Cys48, and Leu54-Cys61, and the existence of a beta-turn in the Gly19-Gly22 region. Our results definitely indicate that the secondary structure of human IGF-I in solution is consistent with that of insulin in the crystalline state.

Amino Acid Sequence↗

PubMed1992

Case report: nephrotic syndrome associated with a total hydatidiform mole.

The authors describe a 51-year-old Japanese woman who developed nephrotic syndrome in association with a total hydatidiform mole. The nephrotic syndrome remitted completely following hysterectomy. A renal biopsy performed before the operation showed diffuse mesangial cell proliferation of a moderate degree, and thickened capillary walls with focal and segmental subendothelial deposits, as well as circumferential mesangial interposition. Occasional foci of the mesangiolysis were also observed. Immunofluorescence microscopy revealed granular staining of IgM along the glomerular capillary walls in a fringe pattern. A review of the literature revealed that this patient appears to be the first case of nephrotic syndrome associated with a total mole, although there have been two cases of nephrotic syndrome due to preeclamptic nephropathy associated with a partial or transitional mole.

Female↗

PubMed1992

Kappa light chain nodular glomerulosclerosis with conspicuous crescent formation and tubulointerstitial injury. Report of a case.

We describe a 39-year-old man who developed kappa light chain nodular glomerulosclerosis with superimposed conspicuous crescent formation and extensive tubulointerstitial injury. The clinical picture was characterized by nephrotic syndrome and rapidly progressive glomerulonephritis. Incessantly progressive loss of renal function culminated in irreversible renal failure 7 weeks after initial manifestations of renal insufficiency. The patient has since been maintained on thrice weekly hemodialysis with chemotherapy for five years. At the time of pathologic diagnosis by renal biopsy, there was no evidence of multiple myeloma, and no serum M-component or Bence-Jones proteinuria was detected. An initial bone marrow aspirate revealed the presence of 0.6% atypical lymphocytes as the sole abnormality, although these were later identified as atypical plasma cells. These cells had also infiltrated the renal interstitium. Crescentic kappa light chain nodular glomerulosclerosis lacking evidence of plasma cell dyscrasia should be included in the differential diagnosis of rapidly progressive glomerulonephritis.

Adult↗

PubMed1992

Genetic polymorphism of human deoxyribonuclease II (DNase II): low activity levels in urine and leukocytes are due to an autosomal recessive allele.

The objectives of this study were to elucidate the genetic basis of human deoxyribonuclease II (DNase II) and to evaluate its usefulness as a genetic and/or diagnostic marker. We have devised a novel, specific and highly sensitive assay method for the urinary and leukocytic enzymes (Yasuda et al. 1991). The distribution of the activities of both enzymes displayed clear-cut bimodality and the Japanese study population could be classified into two distinct types, namely low-activity (DNASE2 L) and high-activity (DNASE2 H), which indicates the existence of a genetic polymorphism in the activity levels of urinary and leukocytic DNase IIs. Close correlations between the leukocytic and urinary enzyme activity levels from the same individuals were observed and the types in the leukocyte samples agreed with the types found in the corresponding urine samples. In a population study of 528 unrelated Japanese individuals, the gene frequencies of the low activity (DNASE2*L) and the high activity (DNASE2*H) alleles were calculated to be 0.632 and 0.368, respectively. The sex and age of individuals did not affect the distribution of DNase II activity levels. The family study results were compatible with the model that the low activity type is due to an autosomal recessive gene, which indicates that DNASE2 L represents homozygosity for DNASE2*L and DNASE2 H corresponds to homozygosity for DNASE2*H and heterozygosity for DNASE2*L and DNASE2*H.

Adult↗

PubMed1992

In vitro antibacterial activities of tosufloxacin against and uptake of tosufloxacin by outer membrane mutants of Escherichia coli, Proteus mirabilis, and Salmonella typhimurium.

The antibacterial activities of tosufloxacin and other quinolones against and apparent uptakes of tosufloxacin and other quinolones by outer membrane mutants of Escherichia coli, Proteus mirabilis, and Salmonella typhimurium were studied. The hydrophobicity of tosufloxacin was nearly equal to that of ofloxacin or lower than those of sparfloxacin and nalidixic acid. OmpF- and OmpC-deficient E. coli and 40-kDa porin-deficient P. mirabilis mutants were twofold more susceptible to tosufloxacin and sparfloxacin but two- to fourfold less susceptible to other quinolones than their parent strains. In S. typhimurium lipopolysaccharide-deficient (rough) mutants, the differences in susceptibility to tosufloxacin were similar to those to sparfloxacin and nalidixic acid. The apparent uptake of tosufloxacin by intact cells was increased in porin-deficient mutants compared with that by their parent strain. These results suggest that the permeation route of tosufloxacin across the outer membrane is different from that of other fluoroquinolones and that tosufloxacin may permeate mainly through the nonporin pathway, presumably phospholipid bilayers. However, this characteristic is independent of the hydrophobicity of the molecule.

4-Quinolones↗

PubMed1992

Stroke volume and cardiac output decrease at termination of obstructive apneas.

Patients with obstructive sleep apnea (OSA) experience repetitive nocturnal oscillations of systemic arterial pressure that occur in association with changes in respiration and changes in sleep state. To investigate cardiac function during the cycle of obstruction (apnea) and resumption of ventilation (recovery), we continuously measured left ventricular stroke volume (LVSV) and mean arterial blood pressure (MAP) during non-rapid-eye-movement sleep in six males with severe OSA (apnea/hypopnea index > or = 30 events/h associated with oxygen saturation < 82%). LVSV was assessed continuously using an ambulatory ventricular function monitor (VEST; Capintec). The apnea-recovery cycle was divided into three phases: 1) early apnea (EA), 2) late apnea (LA), and 3) recovery (Rec). In all subjects recovery was associated with an abrupt decrease in LVSV [54.0 +/- 14.5 (SD) ml] compared with either EA (91.4 +/- 14.7 ml; P < 0.001) or LA (77.1 +/- 15.2 ml; P < 0.005). Although heart rate increased with recovery, the increase was not sufficient to compensate for the decrease in LVSV so that cardiac output (CO) fell (EA: 6,247 +/- 739 ml/min; LA: 5,741 +/- 1,094 ml/min; Rec: 4,601 +/- 1,249 ml/min; EA vs. Rec, P < 0.01; LA vs. Rec, P < 0.025). Recovery was also associated with a significant increase in MAP. We speculate that such abrupt decreases in LVSV and CO at apnea termination, occurring coincident with the nadir of oxygen saturation, may further compromise tissue oxygen delivery.

Adult↗

PubMed1992

Secretion of beta-2-microglobulin from human hepatoblastoma and hepatoma cells on stimulation with interleukin-6.

beta 2-microglobulin (beta 2-M) was secreted in a dose- and time-dependent manner after interleukin-6 (IL-6) treatment of human hepatoblastoma (HuH-6) and hepatoma cells (HuH-7). Pancreatic secretory trypsin inhibitor, which is one of the acute phase proteins secreted in these cells, was also secreted dose- and time-dependently in HuH-6 cells and dose-dependently in HuH-7 cells. It is conceivable that IL-6 induces the production of beta 2-M as an acute phase protein in the liver.

Carcinoma, Hepatocellular↗