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Biomedical subjects

H Wada

Publications and source records attributed to H Wada.

At least 541 records · Page 30Linked to original sources

Omentoplasty for postpneumonectomy bronchopleural fistulas.

Postpneumonectomy fistula is one of the most serious complications in general thoracic surgery and remains difficult to manage. From 1984 to 1991, we successfully used pedicled omentum for the treatment of postpneumonectomy bronchopleural fistulas (omentoplasty) in five patients, four of whom had thoracic empyema. For bronchopleural fistulas without early postoperative infection, single-stage closure was performed which was then covered with pedicled omentum. Omentoplasty was performed successfully in patients with thoracic empyema, after open or closed drainage. Open thoracotomy was useful when closed drainage was ineffective. Even after open thoracotomy, closure of the wound was achieved. All five patients could be discharged. Omentoplasty was useful in the therapy of postpneumonectomy bronchopleural fistula even in the presence of thoracic empyema.

Aged↗

Increased activated protein C-protein C inhibitor complex level in patients positive for lupus anticoagulant.

Activated protein C (APC)-protein C inhibitor (PCI) complex and APC-alpha 1antitrypsin (alpha 1AT) complex levels were measured in 29 patients positive for lupus anticoagulant (LA). LA was considered positive if two of the following three criteria were fulfilled: (1) prolongation of the activated partial thromboplastin time, (2) prolongation of the kaolin clotting time (KCT) and KCT mixing test, and (3) prolongation of the dilute Russell's viper venom time (DRVVT) and DRVVT/DRVVT with high lipid concentration. Plasma thrombin-antithrombin III (AT-III) complex and plasmin-alpha 2-antiplasmin inhibitor complex levels in patients positive for LA were increased slightly, but not significantly, and FDP-D-dimer and t-PA levels were not markedly increased. Plasma PAI-1 level in the LA-positive patients was significantly increased compared with normal volunteers. AT-III activity, protein C antigen, PCI antigen, and protein S antigen levels in the LA-positive patients were virtually normal, while protein C activity was slightly, but not significantly, decreased. APC-PCI complex level was increased in all LA-positive patients, and was not detectable in patients with systemic lupus erythematosus and normal volunteers. APC-alpha 1AT complex was increased slightly, in only two LA-positive patients; it was not detectable in the other patients or in the normal volunteers. These findings suggest that patients positive for LA are in a hypercoagulable state and that protein C activity in such patients is decreased, due to the activation of this protein.

Adult↗

Increased vascular endothelial cell markers in patients with chronic renal failure on maintenance haemodialysis.

Plasma levels of the vascular endothelial cell markers, thrombomodulin (TM), plasminogen activator inhibitor-1 (PAI-1), tissue type plasminogen activator (t-PA), and von Willebrand factor (vWF) were measured in 55 patients on maintenance haemodialysis (HD). TM, PAI-1 and vWF antigen levels were significantly increased in patients before HD, but t-PA antigen was not Compared with levels before HD, t-PA and vWF antigens were significantly increased 1 h after HD and at the end of HD. TM antigen was significantly increased 1 h after HD, and plasma PAI-1 antigen was decreased at the end of HD. TM and vWF antigen levels were negatively correlated with the time (years) on HD. It is concluded that HD may cause endothelial cell damage and that the increases in plasma TM, PAI-1 and vWF levels before HD, and the decrease in the release of TM and vWF antigens from vascular endothelial cells, might be caused by vascular endothelial cell damage from long-term HD.

Adult↗

Hereditary elliptocytosis associated with spectrin Le Puy in a Japanese family: ultrastructural aspect of the red cell skeleton.

A dominantly-inherited hereditary elliptocytosis of intermediate severity was recorded in a Japanese family from Yamagata. The condition was associated with a spectrin truncated beta-chain (MW: 214 kD; 31% of total beta-spectrin), and a defect of mutant spectrin as regards tetramerization and phosphorylation. cDNA analysis revealed skipping of exon X, the third-to-last exon of the spectrin beta-gene. At the gene level, a one-base substitution (A-->G) changed position +4 of the 5' donor splice site consensus sequence of intron X. This mutation has been described before in a French kindred, defining spectrin Le Puy. Electron micrographs following quick-freeze deep-etching showed that the skeletal network was disorganized.

Base Sequence↗

Immunocytochemical characterization and identification of SGE1, a rat glomerular epithelial cell line.

Glomerular epithelial cells (GEC) in culture facilitate the study of glomerular physiology and pathology. However, characterization and identification of GECs in culture have been difficult due to the absence of markers specific to them. We compared the immunocytochemical characteristics of a rat normal GEC line (SGE1) and glomerular cells from rat kidney sections using a lectin and commercially available and newly raised monoclonal and polyclonal antibodies. Antivimentin, anti-dipeptidyl-peptidase-IV (gp 108) and monoclonal antibody 5-1-6 antibodies and Limax flavus lectin bound to visceral GECs, anticytokeratin antibody and antibody against common acute lymphocytic leukemia antigen bound to parietal GECs, and anti-SGE1 cell membrane and monoclonal antibody PHM 5 antibodies bound to both visceral GECs and parietal GECs in normal rat kidney sections, and all of these antibodies and L. flavus lectin consistently bound to SGE1 cells in culture. The pattern of antigenic expression on SGE1 cells indicates that SGE1 cells possess phenotypic characteristics of visceral GECs and parietal GECs, and it further suggests that SGE1 cells may be stem cells or cells undergoing differentiation.

Animals↗

Retinoic acid enhances the number of epidermal growth factor receptors in rat glomerular epithelial cells in vitro.

The renal epithelium appears to be an important target tissue for retinoic acid and epidermal growth factor (EGF). We report here that retinoic acid enhances the proliferative effect of EGF on glomerular epithelial cells (GEC) in vitro and also increases EGF binding to GEC. When GEC were exposed to EGF (> or = 1 ng/ml), cellular DNA synthesis was markedly increased. Moreover, the stimulating effect of EGF was synergistically increased by retinoic acid at 5 micrograms/ml. 125I-EGF binding to cultured GEC was increased approximately 3-fold after addition of retinoic acid to cultures for 48 h. Analysis of 125I-EGF binding revealed 8.1 x 10(4) receptors per control (untreated) cell, while retinoic acid-treated cells demonstrated an increase to 14.3 x 10(4) receptors per cell with no detectable change in receptor affinity. These findings suggest that interactions between retinoic acid and EGF may play an important role in the regulation of GEC growth.

Animals↗

Amino-terminal deletion of 53% of dystrophin results in an intermediate Duchenne-Becker muscular dystrophy phenotype.

We report a Japanese boy with muscular dystrophy whose clinical symptoms were intermediate between those usually considered typical of Duchenne and Becker muscular dystrophies. The patient had a large inframe deletion extending from exons 3 to 41 of the dystrophin gene, which would be expected to cause the production of a dystrophin protein composing only 53% of the normal polypeptide chain. Such an inframe deletion would be expected to cause Becker muscular dystrophy. We did not obtain evidence for alternative splicing or for RNA editing. Immunocytochemical analysis of skeletal muscle showed that a dystrophin-related polypeptide was detectable with antibody directed against the carboxyl-terminal part of the polypeptide but not with antibodies directed against the amino-terminal part, although labeling by antibody against the carboxyl-terminal was faint and patchy. The severity of the disease in this case may be due to the lack of the amino-terminal, actin-binding domain of dystrophin.

Adolescent↗

EFFECT OF MECHANICAL VIBRATION ON ACTIVE TENSION IN THE LONGITUDINAL RETRACTOR MUSCLE OF A SEA CUCUMBER STICHOPUS JAPONICUS

1. The effect of mechanical vibration on active tension in an echinoderm somatic smooth muscle was studied using the longitudinal retractor muscle (LRM) of a sea cucumber Stichopus japonicus. 2. The steady contracture tension in LRM fibres maximally activated with 10(-3) mol l-1 acetylcholine (ACh) was reduced by vibrations (peak-to-peak amplitude, 0.5­2.5 % of l0, where l0 is the slack length of the muscle; frequency, 5­100 Hz). The extent of reduction of active contracture tension increased with increasing amplitude of vibration, but it did not change appreciably with increasing frequency of vibration. 3. The steady contracture tension in LRM fibres submaximally activated with 10(-5) mol l-1 ACh was more markedly reduced by vibrations than was that in maximally activated fibres. 4. The vibration-induced reduction of active contracture tension disappeared when temperature was lowered from 20­23 to 0 °C. 5. The development of contracture tension in LRM fibres activated with ACh was not affected by mechanical vibration. 6. These results are discussed in connection with the vibration-induced decrease in the rate of breakage of the actin­myosin linkages responsible for isometric force generation.

Journal Article↗

[Chemical and chemotaxonomical studies of ferns. LXXXV. Constituent variation of Microlepia marginata (2)].

A new chemotype of Microlepia marginata, P-type strain, was found in the Central districts of Japan. The two main constituents were characterized to be 2 beta,15(R),16-trihydroxy-ent-pimar-7-en-3-one (fumotoshidin A) and 3 alpha-alpha-L-arabinofuranosyloxy-15(R),16-dihydroxy-ent-pimar+ ++-7-ene (fumotoshidin arabinoside). The young fronds of this strain have reddish stripes, which is a common feature to Y-type strains also containing ent-pimarane-type glycosides.

Arabinose↗

Variant type of congenital stomatocytosis.

A 52-year-old female with congenital stomatocytosis showed hemolytic anemia, an increased mean corpuscular volume (MCV), and mean corpuscular hemoglobin concentration (MCHC), reticulocytosis and an increased osmotic fragility. Lipid and protein content of membranes, the activities of membrane-associated enzymes in erythrocytes and the elution pattern of hemoglobin were normal. Erythrocyte Na+ influx was moderately increased and Na+ efflux, particularly ouabain-insensitive Na+ "leak-out" was also increased. K+ concentration of erythrocytes was abnormally low with a slightly increased Na+ content. These phenotypes are very rare, and should be classified as a variant type.

Anemia, Hemolytic, Congenital↗

[Development of a three-dimensional impedance meter and its clinical applicability to diagnosing middle ear diseases].

An impedance meter (IM) is well known to be a valuable apparatus for the diagnosis of secretory otitis media (SOM). However, it is insufficient for the diagnosis of ossicular chain disorders, because the probe tone is limited to one or two frequencies. Therefore, we developed a new IM, with sweeping functions for both frequency and pressure which can display measurement results in a three-dimensional format. In this study, the middle ear dynamic characteristics of normal subjects and patients were measured, and the effects of various kinds of middle ear diseases on these dynamic characteristics were examined. The measurement results of the patients with ossicular chain separation, ossicular chain fixation, SOM, tympanic membrane perforation and tympanic membrane atelectasis showed their own distinctive patterns, and were also clearly different from those of normal subjects. Therefore, it is concluded that this apparatus has a high degree of clinical applicability to the diagnosis of these diseases.

Acoustic Impedance Tests↗

[The effect of aging on middle ear dynamic characteristics].

The effect of aging on middle ear function has not been investigated thoroughly, as there is no simple measuring apparatus except for the conventional impedance meter (IM). However, the reliability of the IM is insufficient, because the stimulus frequency is fixed and the information provided by the IM is minimal. We have developed a sweep frequency middle ear analyzer (MEA), which provides much more information on middle ear dynamic characteristics than a conventional IM, and have obtained various measurements with this device. In this paper, middle ear dynamic characteristics of 187 normal subjects (309 ears) ranging from a 4-year-old child to an elderly person, 79 years old, were measured with the MEA in the middle ear resonance frequency region where dynamic characteristics can be seen clearly, and the effect of aging on middle ear dynamic characteristics was examined. The main results obtained were as follows: Middle ear mobilities tend to increase up to the twenties, then decrease up to the forties. Subsequently, a clear difference between those of males and females is observed. The middle ear mobilities of males decrease gradually with an increase in age. In contrast, although the standard deviation values are large, those for females tend to rise with increasing age.

Adolescent↗

Increased activated protein C-protein C inhibitor complex levels in patients with pulmonary embolism.

Activated protein C (APC)-protein C inhibitor (PCI) complex level was examined in 35 patients with acute pulmonary embolism (PE) and in 20 healthy volunteers. Thrombin-antithrombin III complex, plasmin alpha 2 plasmin inhibitor complex, and fibrin-D-dimer levels were significantly increased in the patients with PE compared to levels in healthy volunteers. Levels of plasminogen activator inhibitor-I, tissue type plasminogen activator, and von Willebrand factor antigens were also significantly increased in patients with PE. Plasma level of APC-PCI complex was increased in most patients with PE and APC-alpha 1 antitrypsin complex level was increased in 13 patients. These complexes were not detected in healthy volunteers. These findings suggested that plasma protein C was activated in patients with PE, and that PCI was the major inhibitor of APC generated in this condition. Thus, regulation of the protein C pathway might play an important role in the pathogenesis of PE.

Adult↗

Generation of self HLA-DR-specific CD3+CD4-CD8+ cytotoxic T cells in chronic graft-versus-host disease.

To analyze the mechanism of chronic graft-versus-host disease (GVHD) characteristic of autoimmune disease, we used a cell-mediated lympholysis assay to study the autoreactivity of PBL from two patients after MHC-matched BMT. Our data indicate the induction of CD3+CD4-CD8+ autoreactive cytotoxic T lymphocytes (CTL) in the one patient with chronic GVHD and an important role for allo-non-MHC (minor histocompatibility) antigen-specific CD3+CD4+CD8- helper T cells in this induction. Experiments using HLA-DR gene-transfected mouse L cells as target cells and blocking assays with anti-HLA class I and class II antibodies provided evidence that autoreactive CTL recognized HLA-DR antigen on autologous cells. Analysis of antigen-specific T cell proliferative responses in these patients to examine the effect of self HLA-DR-specific CTL on the antigen presenting cell (APC)-T cell interaction suggested that donor bone marrow-derived self HLA-DR-specific CTL are responsible for the decreased antigen-presenting ability of the patient's APC. These results suggest a new interpretation of the induction mechanism of chronic GVHD and its associated immunosuppression after MHC-matched BMT based on diminished APC function.

Antibodies, Monoclonal↗