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Biomedical subjects

M Okada

Publications and source records attributed to M Okada.

At least 991 records · Page 55Linked to original sources
PubMed1993

Effects of indeloxazine hydrochloride, a cerebral activator, on passive avoidance learning impaired by disruption of cholinergic transmission in rats.

The effect of indeloxazine [(+/-)-2-[(inden-7-yloxy)methyl]morpholine hydrochloride, YM-08054], a cerebral activator, on passive avoidance learning by disruption of cholinergic transmission was investigated in rats. Indeloxazine prolonged the latency for stepping out of an illuminated compartment into a dark compartment, in both mature and aged rats. Disruption of cholinergic transmission was induced by injection of scopolamine, ethylcholine, treatment with aridinium ion (AF64A) and by lesioning the nucleus basalis magnocellularis. The shortened latency in these models was prolonged when indeloxazine was administered before training in doses which did not affect spontaneous movement or the response to pain in mature rats and administration of indeloxazine, immediately after training, also had an ameliorating effect on passive avoidance in the lesioned rats. In biochemical studies, indeloxazine increased the extracellular concentration of acetylcholine in the frontal cortex of mature rats. These results suggest that indeloxazine possesses facilitatory effects on cerebral function, in part due to activation of the central cholinergic system.

Acetylcholine↗
PubMed1993

The lung in polyarteritis nodosa: a pathologic study of 10 cases.

Polyarteritis nodosa (PAN) is characterized by necrotizing arteritis of medium-sized and small arteries in various organs. Pulmonary artery involvement in PAN has been considered rare. Previously, it also has been thought that patients with PAN do not have interstitial pneumonitis and fibrosis. A detailed pathologic analysis of pulmonary diseases associated with PAN was made in 10 autopsy cases of PAN. Arteritis affecting bronchial arteries was present in seven patients (70%). The data obtained suggest that arteritis in the lung in patients with PAN is more common than has been recognized previously. Diffuse alveolar damage (DAD) involving all lobes bilaterally was present in five patients; it was acute in two patients and organizing in three. In the patients with organizing DAD the degree of fibrosis in the interstitium differed among the lobes, and the fibrosis was more severe in the lower lobe than in the other lobes. Two patients presented with interstitial fibrosis with honeycomb lung of the posterior and lateral basal segments of the lower lobes of both lungs; in one of these patients interstitial fibrosis was present in an area of organizing DAD. Five patients died of respiratory failure resulting from DAD. In conclusion, it is important to consider DAD and interstitial fibrosis as complications of PAN.

Adolescent↗
PubMed1993

Functional properties of the allotypes of mouse complement regulatory protein, factor H: difference of compatibility of each allotype with human factor I.

Three allotypes of mouse factor H, H.1, H.2, and H.3 were purified from the sera of mice with different factor H allotypes, and their functional properties were investigated. The three allotypes all bound to heparin, DNA, Con A, and methylamine-treated mouse C3 (C3(MA)mo) with similar affinities for each protein immobilized, showed identical mobilities on SDS-PAGE, and were reacted well with rabbit polyclonal antibody against H.1 and H.2. Factor I-cofactor activity of these factor H allotypes was measured using highly purified material of mouse, guinea-pig, and human origin. In a homologous system, these allotypes expressed indistinguishable mouse factor I (Imo)-cofactor activity for the cleavage of C3(MA)mo. Imo-cofactor activity was again indistinguishable in these allotypes when methylamine-treated human C3 (C3(MA)hu) or methylamine-treated guinea-pig C3 (C3(MA)gp) was substituted for the C3(MA)mo substrate. The cofactor activity of these factor H allotypes, however, was augmented 4-5 times if C3(MA)hu) was used instead of C3(MA)mo, and was barely detected if C3(MA)gp was employed. In contrast, differences in the potency of the cofactor activity for the three allotypes were revealed if human factor 1 (Ihu) was substituted for Imo: the order of the efficiency for the cleavage of C3(MA)hu was H.2 > H.1 = H.3. These results, taken together with the finding that the homologous combinations of mouse and human factors H and I expressed greater activity for the cleavage of C3(MA)hu than did the heterologous combinations of factor H and factor I, suggest that mouse factor H allotypes discriminate species of protease factor I but not those of substrate (C3(MA), and H.2 possesses the best compatibility for Ihu in C3(MA)hu inactivation.

Animals↗
PubMed1993

Increased levels of tumor necrosis factor and interleukin 1 in bronchoalveolar lavage fluids from pigs infected with Mycoplasma hyopneumoniae.

We examined the levels of tumor necrosis factor (TNF)-alpha and interleukin-1 (IL-1) in bronchoalveolar lavage fluids (BALF) from pigs experimentally infected with Mycoplasma hyopneumoniae using biological assays with WEHI-164 cells and D10.G4.1 cells, respectively. Increased TNF-alpha and IL-1 in BALF were found in infected pigs with gross and/or microscopic lesions. A time-course study suggested TNF-alpha and IL-1 to be persistently elevated in infected pigs. Their presence in BALF would thus appear to be associated with the development of pneumonic lesions in M. hyopneumoniae infected pigs.

Animals↗
PubMed1993

Evaluation of tumor markers in patients with squamous cell carcinoma in the oral cavity.

Serum levels of six tumor markers (carcinoembryonic antigen (CEA), squamous cell carcinoma antigen (SCCA), immunosuppressive acidic protein (IAP), alpha-fetoprotein (AFP), ferritin (FER), and carbohydrate antigen 19-9 (CA 19-9)) were simultaneously measured in 29 patients with primary squamous cell carcinoma (SCC) of the oral cavity to determine their significance. The positive rates were 34.5% for CEA, 41.4% for SCCA, 51.7% for IAP, 0% for AFP, 10.3% for FER, and 6.9% for CA 19-9 in patients with oral SCC. Therefore, CEA, SCCA, and IAP levels, of which the positive rates were significantly different (P < 0.01) from those of control patients without oral cancer, were considered to be of diagnostic value. The sensitivity (69.0%) and accuracy (90.3%) of the combination assay with these three tumor markers proved to be higher than those obtained with individual markers. A combination assay with CEA, SCCA, and IAP could be useful for the screening of patients with oral cancer.

Adult↗
PubMed1993

In situ expression of cytokines in IgA nephritis.

We studied mRNA and protein expression of interleukins (IL) and tumor necrosis factor (TNF) in renal tissues biopsied from 40 patients with IgA nephritis. Immunofluorescent staining with antibodies to IL-1 alpha, IL-1 beta, IL-6, IL-8, TNF-alpha, and TNF-beta was intense in the cytoplasm of cells in glomeruli, which were dual-stained with an anti-monocyte-macrophage antibody. In addition, moderate immunofluorescence for TNF-alpha, and weak staining for IL-1 alpha and IL-6 were occasionally found in resident glomerular cells. Immunoperoxidase-in situ hybridization dual-labeling revealed that IL-1 alpha, IL-6, and TNF-alpha mRNA signals were present in intraglomerular cells reactive with anti-monocyte-macrophage antibody, which further supported the immunofluorescent findings. Cells expressing IL-1 alpha, IL-1 beta, IL-6, IL-8, TNF-alpha, and TNF-beta were also observed in the interstitium. Most of these cells were also labeled with the anti-monocyte-macrophage antibody. The number of IL-1 alpha, IL-6, and TNF-alpha-positive cells infiltrating the glomerulus significantly correlated with mesangial hypercellularity. IL-8 and TNF-alpha-positive intraglomerular cells were correlated with the magnitude of proteinuria. The population of interstitial cells positive for IL-1 alpha, IL-6, IL-8, and TNF-alpha was associated with the grade of tubulointerstitial changes and proteinuria. There was no correlation between local IL-1 alpha, IL-6, and TNF-alpha expression in glomeruli or interstitium and serum or urinary levels of the respective cytokines.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1993

Prediction of plasma concentrations of mianserin and desmethylmianserin at steady state from those after an initial dose of mianserin.

The relationships between the plasma concentrations of mianserin and desmethylmianserin at 18 h after initial dosing and those at steady state were studied in 19 depressed patients receiving 30 mg of mianserin at bedtime. Significant linear relationships were observed for mianserin, desmethylmianserin, and mianserin plus desmethylmianserin. The present study thus suggests that the plasma concentrations of these compounds after an initial dose of mianserin can be used for the prediction of an optimal dose.

Adult↗
PubMed1993

Surgical treatment for aneurysms of the descending aorta using temporary perfusion by a centrifugal pump: clinical analysis of 33 cases.

Since 1987, 33 patients have undergone surgery at Kobe University Hospital for aneurysm of the descending aorta using left heart bypass with a heparin-coated centrifugal pump and heparin-coated tubes. Sixteen patients had true aneurysms of the descending thoracic aorta, 7 had thoracoabdominal aneurysms, and 10 had aortic dissection (DeBakey's Type III). Heat exchangers and oxygenators were not included in the bypass circuit in any of the cases. Perfusion time was from 42 to 205 min (average 90 min). Left heart bypass was established with 1 mg/kg of systemic heparinization in 5 cases, 0.5 mg/kg in 5 cases, and 0 mg/kg in 23 cases. There were no complications such as perioperative embolism, acidosis, or hypothermia. During aortic cross-clamping, the arterial pressure of the lower extremity was maintained above 70 mm Hg, but there was no relationship between the distal perfusion pressure and bypass flow. The urine output during left heart bypass was related to the distal perfusion flow by centrifugal pump. Of 23 patients who underwent bypass with less than 40 ml/kg/min of distal perfusion flow, 7 showed transient renal dysfunction postoperatively, and 1 developed postoperative renal failure. The other patients who were bypassed with over 40 ml/kg/min of pump flow stayed in the normal range of renal function. Postoperative paresis occurred in 2 patients, who were also perfused with less than 40 ml/kg/min of bypass flow. It could be concluded that left heart bypass by centrifugal pump is safe and acceptable as a circulatory support in the surgical treatment of aneurysm of the descending aorta.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

Beneficial circulatory support by left heart bypass with a centrifugal (BioMedicus) pump for aneurysms of the descending thoracic aorta.

A comparative study between left heart bypass with a centrifugal (BioMedicus) pump and with a temporary external shunt was performed to assess the efficacy of distal organ perfusion in the surgical treatment of 31 patients with aneurysm of the descending thoracic aorta. Eighteen patients were supported with a centrifugal pump, and the remaining 13 were supported by temporary shunt with either a Gott shunt or a Dacron graft. Heparinless bypass with a centrifugal pump provided a significant decrease of intraoperative blood loss and blood transfusion by the combined application of Cell-Saver. The pressure difference between upper and lower extremities decreased (p < 0.05) in the centrifugal pump group even with aortic cross-clamping, and the urine output increased during operation. Among 13 patients supported with the temporary shunt, 3 had postoperative renal failure, and 2 died of it. All patients with a centrifugal pump survived without any complications. It could be concluded that the left heart bypass with a centrifugal (BioMedicus) pump was safe and was favorable for support of the distal circulation during aortic cross-clamping and to prevent ischemic complications such as renal failure and spinal cord injury.

Adult↗
PubMed1993

[Rapid diagnosis of cytomegalovirus interstitial pneumonitis by the polymerase chain reaction method--comparison of four diagnostic procedures].

The authors conducted a comparative study on the rapid diagnosis of cytomegalovirus (CMV) interstitial pneumonitis by 4 different methods. Among them, the polymerase chain reaction (PCR) method was found to achieve the most rapid diagnosis of CMV infection. The clinical usefulness of making a diagnosis from the serum antibody titer and viral isolation was questionable as compared with the PCR method. Therefore, early diagnosis of CMV infection by PCR may be promising especially for the compromised patients with hematological diseases.

Base Sequence↗
PubMed1993

Chemotaxis of leptospires to hemoglobin in relation to virulence.

A guinea pig-lethal line of Leptospira interrogans serovar copenhageni strain Shibaura, but not an avirulent line of the same strain, moved in larger numbers toward hemoglobin than toward distilled water (control) in a U-shaped polypropylene tube. L. interrogans serovar lai strains 017 and KH-1, which were also guinea pig lethal, showed a similar move to hemoglobin. No such move toward hemoglobin was shown by 14 avirulent strains of L. interrogans (with one exception) or any of the 8 strains of L. biflexa tested.

Animals↗
PubMed1993

Serum amyloid A protein in acute viral infections.

Concentrations of serum amyloid A protein (SAA) were measured in 254 children with viral diseases, including measles, varicella, rubella, mumps, echo-30 meningitis, chronic hepatitis B and C, and in eight with Kawasaki disease. Latex agglutination nephelometric immunoassay was used for assaying SAA. In 191 out of 195 patients (98%), SAA concentrations became markedly raised in the acute phase of the viral disease: measles (97%), varicella (100%), mumps (95%), and echo-30 meningitis (99%) with mean titres of 82.4, 80.5, 60.2, 75.2, and 101.1 micrograms/ml respectively. This increase in SAA was followed by a rapid return to normal concentrations (< 5 micrograms/ml) during convalescence. Remarkably higher concentrations of SAA (mean 1630 micrograms/ml) were detected in the acute phase of patients with Kawasaki disease, but in most of the children with chronic hepatitis B or C, the titres of SAA remained normal. There was no close correlation between SAA and serum concentrations for alpha 1-acid glycoprotein, beta 2-microglobulin, transferrin, and IgG. There was a clear correlation between SAA and C reactive protein concentrations, although SAA showed a greater incremental change than C reactive protein in the acute phase. In the acute phase of these viral diseases, 56% of the patients had raised SAA concentrations (> or = 5 micrograms/ml) with normal C reactive protein concentrations (< 5 micrograms/ml). These results indicate that SAA could be useful as an inflammatory marker in children with acute viral infections.

Acute Disease↗
PubMed1993

Transient hyperopia with lens swelling at initial therapy in diabetes.

The clinical courses of 10 eyes of five diabetic patients who exhibited bilateral transient hyperopia (maximum: 1:1-4.9 dioptres, spherical equivalent) after initiation of strict control of diabetes with or without insulin are reported. The hyperopia occurred within a few days after abrupt decrease in plasma glucose, progressed to maximum at days 7-14, and regressed gradually over 1 month thereafter. Transient cycloplegia had no effect on refractive error. During hyperopia, there were no significant changes in axial length or corneal curvature. However, thickened lens, decreased anterior chamber depth, and transient cataract were observed to significant degrees. It is suggested that the transient hyperopia, with lens swelling and opacity, was caused by decreased lens refractive index following water influx.

Adult↗
PubMed1993

Intestinal Behçet disease: serial changes at radiography.

To clarify the characteristic radiographic findings and serial radiographic changes in nonsurgical cases of intestinal Behçet disease (BD), seven patients were followed up for an average of 4 1/2 years (range, 8 months to 11 years 4 months). They underwent repeated examination with barium meal studies and double-contrast barium enema meal studies and double-contrast barium enema radiography. Initial radiography revealed one to three deep ulcers in the terminal ileum or ileocecal region in five patients. The ulcers healed while patients were treated with medical therapy but recurred during the follow-up period. In four of these five patients, follow-up radiography demonstrated various changes within each case: At each examination, an enlarged ulcer or a newly developed ulcer was often found in conjunction with a healed ulcer. In the other two patients, multiple shallow ulcers or innumerable aphthoid ulcers were seen throughout the entire colon, and these ulcers showed a good response to medical treatment. These results indicate that serial radiographic changes in patients with intestinal BD may mimic those in patients with Crohn disease, with findings in the terminal ileum and colon that wax and wane with medical treatment.

Adult↗
PubMed1993

Endogenous sulfhydryls in healing gastric mucosal injury induced by HCl in the rat.

The role of endogenous sulfhydryls (SH) in the healing of HCl-induced gastric injury was investigated in the rat. The animals fasted for 18 h were given 1 ml of 0.6 N HCl by gavage, and they were fed normally from 1 h later and killed various days after HCl treatment. Gastric lesions induced by HCl healed to quiescent states within 7 days both macroscopically and histologically. Mucosal SH levels were markedly reduced after induction of damage by HCl, but recovered gradually to or above normal values within 5 days. Gastric acidity was also significantly reduced after administration of 0.6 N HCl (induction of lesions), followed by a return to normal values within 5 days, although the volume of gastric contents remained unchanged before and after HCl treatment. The healing of HCl-induced gastric lesions was significantly impaired by diethylmaleate (DEM 0.3 ml/kg x 2) when this drug was given subcutaneously for 5 days. Glutathione (GSH: 100 mg/kg x 2) alone did not affect the healing of gastric lesions, but the combined administration of GSH with DEM significantly antagonized the delayed healing caused by DEM. Administration of DEM caused a marked and persistent reduction in the mucosal SH contents, while GSH by itself significantly increased the mucosal SH levels and partially reversed the reduced SH contents caused by DEM. Gastric acid secretion was not significantly altered by either DEM or GHS. These results suggest that endogenous SH may play some roles in the healing process of gastric mucosal lesions. DEM caused a deleterious effect on the healing of gastric lesions, probably by reducing the mucosal SH.

Animals↗
PubMed1993

Purification of a trypsin-type protease from human umbilical vein endothelial cells which is highly sensitive to the Kunitz inhibitor domain peptide of Alzheimer's disease amyloid protein precursor.

A trypsin-type protease was purified to enzymatic homogeneity from human umbilical vein endothelial cells by sequential affinity chromatographies. The enzyme specifically hydrolyzed dibasic substrates with leucine at the P3 positions, but scarcely hydrolyzed the other substrates tested. The enzyme was strongly inhibited by the Kunitz inhibitor domain peptide of Alzheimer's disease amyloid protein precursor (Ki value, 0.35 nM) and by the microbial inhibitors leupeptin and anti-pain. These results, together with a previous finding of a significant increase in the expression of Alzheimer's amyloid protein precursors (beta APPs) with the Kunitz inhibitor domain in Alzheimer's disease, suggest that the activity of the trypsin-type protease is suppressed by an increase of beta APPs with inhibitor activity in Alzheimer's disease, resulting in aberrant intracellular protein catabolism including degradation of beta APPs and beta-protein deposition.

Amino Acid Sequence↗
PubMed1993

Epiretinal membrane of proliferative diabetic retinopathy: an immunohistochemical study.

Nineteen cases of epiretinal membrane (ERM) in proliferative diabetic retinopathy were studied using immunohistochemical methods. Antibodies against type I-IV collagen, fibronectin (FN), glial fibrillary acidic protein (GFAP), vimentin and the monoclonal antibody (MAB) against human Müller cells were used to examine the membranes. Type II collagen was found on one side of the ERMs in 95% of the cases. The other types of collagen, FN and vimentin were also identified in most cases. Müller cells (GFAP- and MAB-positive) were found in 2/19 cases (11%), and astrocytes (GFAP-positive but MAB-negative) were found in 10/19 cases (53%). These results suggest that type II collagen (vitreal collagen) may act as a scaffolding in the formation of ERMs and that glial elements of the ERMs consist mainly of astrocytes.

Adult↗