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Biomedical subjects

H Maeda

Publications and source records attributed to H Maeda.

At least 847 records · Page 47Linked to original sources
PubMed1990

Activation of the plasma kallikrein-kinin system by Candida albicans proteinase.

An extracellular carboxyl proteinase produced by the yeast Candida albicans enhanced vascular permeability when injected into the dorsal skin of guinea pigs. The character and mechanism of the permeability-enhancing reaction were studied in vivo and in vitro. Permeability was not enhanced when the C. albicans proteinase was heat treated (100 degrees C, 5 min) or when it was treated with pepstatin, a specific carboxyl proteinase inhibitor. The permeability reaction induced by the C. albicans proteinase was not affected by pretreatment with antihistamine but was greatly augmented by simultaneous injection of a kinin potentiator, carboxypeptidase N inhibitor. However, the simultaneous injection of a kinin-degrading enzyme, carboxypeptidase B, interfered with the reaction. Furthermore, in vitro conversion of plasma prekallikrein to kallikrein by the C. albicans proteinase was observed, and the reaction was inhibited by corn trypsin inhibitor, an inhibitor of activated Hageman factor, and soybean trypsin inhibitor, a well-known inhibitor of plasma kallikrein. These results indicate that C. albicans proteinase enhances vascular permeability through activation of the plasma kallikrein-kinin system, which generates bradykinin.

Animals↗
PubMed1990

Establishment and characterization of a human ovarian serous cystadenocarcinoma cell line that produces the tumor markers CA-125 and tissue polypeptide antigen.

A cultured cell line (SHIN-3) derived from a human ovarian serous cystadenocarcinoma which consistently produces two tumor markers, CA-125 and tissue polypeptide antigen (TPA) was established. After 1 week of culture of 1 x 10(5) cells, high levels of tumor marker were observed (the total CA-125 release was 1,500 U and the total TPA release was 37.5 U). Expression of CA-125 and TPA was also demonstrated in cultured cells immunohistochemically. The volume of CA-125 release per cell was highest just before the start of the logarithmic growth phase. TPA production was increased in the logarithmic growth phase, but its relationship to the total number of cells was not clear.

Animals↗
PubMed1990

Ultrasonic evaluation of early carotid atherosclerosis.

We investigated the prevalence of carotid atherosclerosis, including mild early lesions, and its association with cervical bruits and various risk factors (age, male sex, hypertension, hyperlipidemia, diabetes mellitus, obesity, and cigarette smoking) in 232 consecutive Japanese patients. High-resolution real-time B-mode ultrasonography was performed to determine the extent of atherosclerosis, and it was quantified by using a scoring system. The prevalence of carotid atherosclerosis was 49%, 59%, and 41% in all 232 patients, the 100 symptomatic patients, and the 132 asymptomatic patients, respectively. Although carotid lesions were detected frequently (87%) in the 30 patients with cervical bruits, bruits were noted in only 30% of the 88 examined patients with carotid atherosclerosis. Independent risk factors for carotid atherosclerosis in these patients were found to be age, male sex, and hyperlipidemia; diabetes mellitus was a possible risk factor for carotid atherosclerosis. Our study did not show a close association between hypertension and carotid atherosclerosis, and this might be caused by the high prevalence of hypertension in our patients. Our findings suggest an increasing prevalence of carotid atherosclerosis in the Japanese, though this should be confirmed in a population-based study. Our study demonstrates the clinical usefulness of high-resolution B-mode ultrasonography for the evaluation of early carotid atherosclerosis.

Adult↗
PubMed1990

Analysis of HLA antigens in patients with diffuse panbronchiolitis.

A new clinicopathologic entity, diffuse panbronchiolitis, was recently reported in Japan. This disorder is characterized by recurrent sinopulmonary infection and respiratory bronchiolitis. We identified cases of familial diffuse panbronchiolitis and found that many siblings of the patients had paranasal sinusitis. Because of this, we performed HLA analysis of the patients with diffuse panbronchiolitis. In HLA Class I and Class II antigens, Bw54 significantly increased (frequency: 63.2%; RR = 13.30; corrected p value less than 1.08 x 10(-10], whereas Cw1 and MC1 (a new HLA-DR-related antigen) slightly increased. These increases might be explained by the fact that these two antigens, Cw1 and MC1, formed a haplotype with Bw54, which suggests that one or some of the genes controlling the susceptibility and/or immune responsiveness of diffuse panbronchiolitis might be located near HLA loci. In addition, Bw54, or its related haplotype, exists only in Japanese, Chinese, and Korean populations. This may explain why a similar disease had not been reported in the English literature.

Asian People↗
PubMed1990

Dependence on O2- generation by xanthine oxidase of pathogenesis of influenza virus infection in mice.

We evaluated various biochemical parameters in influenza virus-infected mice and focused on adenosine catabolism in the supernatant of bronchoalveolar lavage fluid (s-BALF), lung tissue, and serum (plasma). The activities of adenosine deaminase (ADA) and xanthine oxidase (XO), which generates O2-, were elevated in the s-BALF, lung tissue homogenate, and serum (plasma). The elevations were most remarkable in s-BALF and in lung tissue: We found a 170-fold increase in ADA activity and a 400-fold increase in XO activity as measured per volume of alveolar lavage fluid. The ratio of activity of XO to activity of xanthine dehydrogenase in s-BALF increased from 0.15 +/- 0.05 (control; no infection) to 1.06 +/- 0.13 on day 6 after viral infection. Increased levels of various adenosine catabolites (i.e., inosine, hypoxanthine, xanthine, and uric acid) in serum and s-BALF were confirmed. We also identified O2- generation from XO in s-BALF obtained on days 6 and 8 after infection, and the generation of O2- was enhanced remarkably in the presence of adenosine. Lastly, treatment with allopurinol (an inhibitor of XO) and with chemically modified superoxide dismutase (a scavenger of O2-) improved the survival rate of influenza virus-infected mice. These results indicate that generation of oxygen-free radicals by XO, coupled with catabolic supply of hypoxanthine from adenosine catabolism, is a pathogenic principle in influenza virus infection in mice and that a therapeutic approach by elimination of oxygen radicals thus seems possible.

Adenosine↗
PubMed1990

HLA antigens in Japanese patients with myasthenia gravis.

HLA antigens in 104 Japanese patients and 41 families with myasthenia gravis (MG) were investigated. The frequencies of DR9 and DRw13 were significantly increased in the patients who developed MG before 3 yr of age. The DQw3 antigen was positive for all the patients that developed MG before 15 yr with only one exception. All the examined cases that developed MG before 3 yr (including this DQw3 negative patient) had the same DQA and DQB DNA restriction fragments. These HLA frequencies decreased as the age of onset increased, and no significant association was observed in adult-onset MG. No patients had B8, DR3, and DQw2. The relative risk was higher for the DR9/DRw13 heterozygotes (37.4) than for DR9 (16.4) or DRw13 (7.1) in the childhood-onset MG. Statistical analysis suggested that DR9 and DRw13 (or DQw1 and DQw3) act synergistically in the disease development. Family study revealed diverse DR9 haplotypes. The most frequent DRw13 haplotype was Bw44-BFF-C4A3B1-DRw13-DQw1, which may be evolutionarily related to the caucasian B8-DR3-DQw2 haplotype. These results showed that MG in early childhood in Japanese individuals is genetically different from that in adulthood and that in caucasians.

Age Factors↗
PubMed1990

Relationship between liver degeneration and the production of dark firm dry meat in slaughtered pigs.

Sixty-five of 77 slaughtered pigs with liver degeneration produced dark firm dry (DFD) meat. The biochemical properties of blood, liver and muscle of those pigs were examined. In the blood, the NEFA level was higher, which indicated the mobilization of lipids from adipose tissues. The serum CPK and LDH5 levels were higher, the enzymes being derived from muscle. In the degenerative liver with yellowish discoloration, the TG level was higher and the glycogen level was lower than in a normal liver. In the DFD muscle with the final pH above 6.0, both the glycogen level immediately after slaughter and the lactic acid level 24 hr after slaughter were lower than in a normal muscle with the final pH below 6.0. Five pigs exhausted experimentally by 53-hr fasting and hard exercise showed the same changes in the blood and liver as the pigs with liver degeneration. Four of the 5 exhausted pigs showed the same changes in the muscle as in DFD meat. From these data, it was confirmed that exhaustion before slaughter led to lipid accumulation in the liver and to a decrease in muscle glycogen, and consequently caused both liver degeneration and DFD meat in the same pig.

Alanine Transaminase↗
PubMed1990

Bronchial hyperreactivity in patients with mitral valve disease.

To elicit the mechanism of bronchial hyperreactivity (BHR) in chronic heart failure (CHF), a methacholine inhalation test, pulmonary function test, and cardiac catheterization were performed in 19 patients with mitral valve disease (MVD), and the change of severity of BHR before and after mitral valve replacement (MVR) was also examined in seven of 19 patients with MVD. Sixteen of 19 patients with MVD showed significant increase in respiratory resistance in methacholine inhalation test, while all normal subjects did not. The maximal expiratory flow at 25 percent of vital capacity (Vmax25), a parameter of small airway disease, correlated significantly with log cumulative dose producing a 35 percent decrease in respiratory conductance (PD35Grs) (r = 0.536) and the duration of symptoms (r = -0.682). There was a significant correlation between log PD35Grs and mean pulmonary artery wedge pressure (r = -0.466). After MVR, log PD35Grs was significantly improved in all seven operated-on patients, although six patients retained BHR. We conclude that patients with long-term MVD have marked BHR and that BHR in long-term MVD is related to peripheral airway narrowing with organic remodeling, which was not ameliorated with MVR procedure, in addition to pulmonary congestion.

Bronchial Provocation Tests↗
PubMed1990

Enzymatic removal of bilirubin toxicity by bilirubin oxidase in vitro and excretion of degradation products in vivo.

The toxic effects of the degradation products of bilirubin that were formed by reaction with bilirubin oxidase were investigated with the C 1300 mouse neuroblastoma cell line by examining the following parameters: growth inhibition, morphologic characteristics, membrane transport, DNA synthesis, and protein synthesis. The addition of bilirubin to the cells resulted in definite cytotoxic effects on all of these parameters in a dose-dependent fashion; the addition of bilirubin oxidase reversed the toxic effects on the C 1300 cells in vitro. Furthermore, we found that most of these enzymatic degradation products of bilirubin were excreted by the kidney into the urine in a few hours after intravenous injection of the degradation products; in contrast, no intact bilirubin was excreted. Thus, these findings suggest that hyperbilirubinemia in newborn infants (kernicterus) may be prevented by administering polyethylene glycol-conjugated bilirubin oxidase, with a longer plasma half-life which has been reported previously to oxidize bilirubin to its nontoxic components in the bloodstream.

Animals↗
PubMed1990

CP-84,657, a potent polyether anticoccidial related to portmicin and produced by Actinomadura sp.

A new polyether antibiotic CP-84,657 (C45H78O14) was isolated by solvent extraction from the fermentation broth of Actinomadura sp. (ATCC 53708). Following purification by column chromatography and crystallization, the structure of CP-84,657 was elucidated by spectroscopic (NMR and MS) methods. The absolute stereochemistry was determined by a single crystal X-ray analysis of the corresponding rubidium salt. CP-84,657 is among the most potent anticoccidal agents known, effectively controlling the Eimeria species that are the major causative agents of chicken coccidiosis at doses of 5 mg/kg or less in feed. It is also active in vitro against certain Gram-positive bacteria, as well as the spirochete, Treponema hyodysenteriae.

Actinomycetales↗
PubMed1990

[A new monoclonal antibody (SH-9) recognizes the low molecular mass of ovarian cancer antigen CA125].

The SHIN-3 cell line producing CA125 was established from an ovarian cancer patient. Using the SHIN-3 cell line, we found that the low-molecular-mass antigen (about 50 KDa) might be the main antigenic determinant in CA125-immunoreactive species. A new monoclonal antibody to this low-molecular-mass was raised to examine a new cancer associated antigen by a hybridoma technique. Using enzyme linked immuno sorbent assay, ten clones were selected from among 398 clones. Two clones were IgG1 and eight were IgM. By immunostaining (ABC assay), a new antibody (named SH-9) reacted with normal pulmonary bronchus and uterine cervical glands. No positivity, however, was observed in endometriosis (adenomyosis). In tumorous lesions of ovary, SH-9 antibody reacted specifically with mucinous cystadenoma-benign, borderline or malignant. However, no positivity was found in serous cystadenocarcinoma. In any other carcinomas, only lung cancer (adenocarcinoma, squamous cell carcinoma) showed a clear positivity. Immuno blotting analysis showed that SH-9 antibody recognized a low molecular mass. Therefore, SH-9 is seen to be an extremely unique antibody when compared with OC125 biochemically and histochemically.

Antibodies, Monoclonal↗
PubMed1990

[An experimental study of the orthodontic force effect on internal remodeling of mandibular bone].

The role of mechanical stress in determining bone structure by influencing its cellular processes during remodeling has been discussed. But previous studies have not provided an adequate background of knowledge to explain the effect of orthodontic force in internal remodeling of the bones. This study was performed to determine the relationship between stress distribution induced by orthodontic force and alteration of internal remodeling in mandibular bone. Seven young adult mongrel dogs of unknown age were used as experimental animals. The bilateral lower 4th premolars were extracted. After 106 days, the 3rd premolars on the right side were moved distally by coil springs for 106 days. Twice pulse labels of tetracycline and calcein were performed to obtain histomorphometric parameters of cortical bones prior and posterior to tooth movement. With the use of microscopic plotting tool and minicomputer, the direction of haversian systems was reconstructed three-dimensionally. To make a comparison with the alteration of histomorphometric parameters and direction of Haversian systems, the principal stress distribution of mandibular bone caused by orthodontic force was obtained by means of 3-D finite element method analysis. Experimental results indicate as follows. 1. The osteoid seams number per unit area (OsAf) and the labeled surface per unit area (TcAf) increased significantly at both alveolar and basal bone region compared with control side. 2. The resorption cavities number per unit area, (Ar) increased significantly at alveolar bone region. But no significant changes were noted at basal bone region. 3. No significant differentiations were noted in mineral appositional rate (Mo) between any bone regions nor label timings. 4. There is large variance between the direction of Haversian systems and the maximal principal stress vector. But a significant alteration of the direction of Haversian systems was found in highly stressed and younger bone areas. From these findings, it can be speculated that, as a primary reaction of bone against stress, the optimum microscopic structural change took place in areas of bone which bore tension or pressure due to excess stress, at the same time the internal remodeling of bone was accelerated by increase of activation frequency (mu), accompanied with no increase of remodeling periods (sigma).

Animals↗
PubMed1990

Safety of cordocentesis under ultrasound guidance for fetal blood sampling.

In the present study, we attempted to assess the safety and the risk of cordocentesis under ultrasound guidance for fetal blood sampling. Forty-five cordocenteses in 43 cases were carried out. These forty-three cases included 23 nonimmunologic hydrops fetalis, 12 congenital fetal malformations, 3 chromosome aberrations, 3 Rh isoimmunization, and 2 idiopathic thrombocytopenic purpura. Gestational age when cordocentesis was performed ranged from 17 to 39 weeks of gestation. In 42 (93.3%) out of 45 procedures, pure fetal blood was obtained. Postpuncture bleeding was observed in 17 cases (37.8%). In 12 (70.6%) out of 17 cases, bleeding stopped within 2 minutes. In only one case, bleeding continued for 11 minutes and cesarean section was performed due to fetal distress. Cardiotocogram obtained after cordocentesis revealed no ominous signs in the other 44 procedures. The other complications, including premature rupture of the membranes, premature labor, and intrauterine infection, did not occur during or after this procedure. There were no cases in which any kind of injury to the placenta or umbilical cord was observed.

Blood Specimen Collection↗