Search PubMed⌕ Search

Biomedical subjects

H Maeda

Publications and source records attributed to H Maeda.

At least 1,225 records · Page 68Linked to original sources
PubMed1983

Application of the ammonia gas-sensing electrode: determination of drugs having a carbothionamido group by decomposition with acid.

A method to determine drugs having a carbothionamido group using an ammonia gas-sensing electrode is described. To obtain analytical accuracy, the effect of factors that influence the potential is also discussed. Ethionamide or prothionamide was refluxed with 20% HCl to give ammonium chloride, hydrogen sulfide, and a carboxylic acid. The ammonia, which evolved at pH greater than 11, was determined. A linear calibration plot was obtained within the drug concentration range of 2 X 10(-5)--1 X 10(-2) M.

Amides↗
PubMed1983

Identification of the MT3 molecule using two-dimensional gel electrophoresis and alloantisera.

The MT3 antigen is defined serologically as a DR supertypic specificity and is strongly associated with DR4, DR7, and DRw9. To determine whether the MT3 molecule is distinct from the DR molecule, DR4 and MT3 antigens were immunoprecipitated from 125I-labeled plasma membrane glycoproteins of a DR4-homozygous, MT3-homozygous B lymphoid cell line, Wa, and compared by two-dimensional (2-D) gel electrophoresis. The precipitates with two different anti-DR4 alloantisera and with three different mouse antibodies against human Ia monomorphic determinants gave the same 2-D gel pattern consisting of one heavy chain with a molecular weight of 34 000 and a set of light chains with a molecular weight of 30 000, indicating that these polypeptides are the components of the DR4 molecule. On the other hand, all three anti-MT3 alloantisera used precipitated an identical set of anti-MT3 alloantisera specific light chains with a molecular weight of 30 000, and one heavy chain with a molecular weight of 34 000. The pI of the MT3 light chain was more acidic than that of the DR4 light chain. The amount of MT3 light chains was much smaller than that of DR4 light chains in unlabeled plasma membrane glycoproteins. Thus, we have demonstrated directly using 2-D gel electrophoresis and anti-MT3 alloantisera that the MT3 antigen is a new human Ia molecule distinct from DR4.

Antibodies, Monoclonal↗
PubMed1983

Case report of neuroendocrine carcinoma of the skin, histochemical and electron microscopic study.

A rare case of neuroendocrine carcinoma of the skin in a 83-year-old male Japanese was reported. Histological, electron microscopical and cytological studies were performed on the surgically removed tumor tissue and the cultured tissue. The tumor occurred at the junction of the dermis and subcutaneous tissue of the right elbow, and spread to the right brachial region and axilla. Histologically, the tumor consisted mostly of small anaplastic cells, closely resembling lymphocytes. They showed a characteristic uniformity without rosette or trabecular formation in the usual histological sections, but an epithelial-like arrangement of tumor cells was readily observable both in the tissue culture and imprint preparations. Grimelius' stain was weakly positive in the periphery of the cytoplasm. Neuron Specific Enolase (NSE) activity was high both in the serum and in the tumor mass. No gastro-entero-pancreatic hormones were detected. Electron microscopically, membrane-bound granules of neurosecretory type, 90 to 170 nm in diameter were observed in the cytoplasm. These granules were characteristically distributed along the periphery of cytoplasm beneath the plasma membrane and in clusters in the cell processes. The tumor cells had sparse rudimentary desmosome-like junctions and a few cytoplasmic finger-like projections. Either a neurogenic or APUD cell origin of the tumor was suspected. The serum NSE value, suggesting to be a neurogenic origin before the histological examination in the present case, is considered to be a valuable marker substance for screening and therapeutic monitoring of neurogenic tumors.

Aged↗
PubMed1983

Lesions of the mediodorsal thalamic nucleus do not change thresholds for hypothalamic defensive attack in cats.

Electrolytic lesions of the mediodorsal thalamic nucleus (nMD) were made in 10 cats to evaluate their effects on thresholds for hypothalamic defensive attack and emotional reactivity to noxious stimuli. Only 2 cats showed minimal threshold changes after the lesions, one of which was accompanied by an increased emotional reactivity to noxious stimuli; however, this was attributed to damage to the fornical column. The nMD appeared not to be involved directly in the central mechanism of defensive attack.

Animals↗
PubMed1983

Physical fitness. Its contribution to serum high density lipoprotein.

The effects of exercise conditioning on serum high density lipoprotein cholesterol (HDL-C) were studied using 20 members of a regular joggers club and other healthy non-member subjects of varying degrees of habitual physical activity (253 males and 391 females). Both the HDL-C and HDL-C/serum total cholesterol (TC) levels were significantly higher with the 20 regular joggers than with the sedentary controls matched for age, TC, serum triglycerides (TG) and weight index (WI). A significant correlation was found between HDL-C/TC and the exercise conditioning value obtained by using the results of the 12-min performance test as an index among the non-member subjects. In order to ascertain the relative significance of exercise conditioning in influencing HDL-C/TC, a multiple regression analysis was conducted using HDL-C/TC as the variable criterion. The results showed that TG affected HDL-C/TC the most among both males and females, while exercise conditioning affected it second among males and fourth among females.

Adult↗
PubMed1983

Intestinal absorption and urinary excretion of antitumor peptidomannan KS-2 after oral administration in rats.

A peptidomannan fraction designated as KS-2 was subjected for distribution study after oral administration. KS-2, exhibiting antitumor- and interferon-inducing action, was isolated from hot water extracts of mycelia of Basidiomycetes. For this purpose, KS-2 was labelled with fluorescein isothiocyanate. The amount and location of the labelled KS-2 (F-KS) was determined quantitatively by fluorescence intensity, and the molecular sizes were estimated by the fluorescence polarization method. The present data indicated that F-KS, when given orally, was absorbed partially via portal vein and intestinal lymphatics into the general circulation with intact molecular size. Moreover, F-KS was recovered in urine with concomitant breakdown in molecular weight. Histological evaluation revealed that F-KS was accumulated in the mesenteric lymph nodes, Peyer's patches, spleen, liver, and kidneys. These findings provide evidence that the polysaccharide KS-2 becomes accessible to the immune tissues and the vascular system; thus it may exert potentiating activity of defense system.

Administration, Oral↗
PubMed1983

The micronucleus test with mouse spleen cells.

The results of this study show that the micronucleus test can be carried out with mouse spleen cells as well as with cells from bone marrow. Polychromatic erythrocytes occurred in the spleen at a frequency of about 9% of the whole spleen cells compared with about 13% in the bone marrow. 3 test compounds were used to compare the frequency of micronuclei in cells from the 2 tissues. Mitomycin C and cyclophosphamide induced micronucleated polychromatic erythrocytes in both spleen and bone marrow. Fosfomycin, an antibiotic having a broad spectrum of antimicrobial activities, did not induce micronucleated erythrocytes in either organ.

Animals↗
PubMed1983

Effect of arterial administration of high-molecular-weight anticancer agent SMANCS with lipid lymphographic agent on hepatoma: a preliminary report.

A clinical evaluation of arterial infusion of high-molecular-weight antitumor agent SMANCS dissolved in lipid lymphographic agent (thiodol) in 44 patients with mostly unresectable hepatoma is described. The treatment regimen demonstrated significant merits both therapeutically and diagnostically. Marked antitumor effects were shown in the decreased serum alpha-fetoprotein levels (86% of cases) and tumor size (95% of cases), and in survival period and histological findings. Furthermore, there was increased diagnostic sensitivity using CT scan, plain X-rays or ultrasound. The procedure of selective arterial administration of 3-4 mg of SMANCS in 3-4 ml of ethiodol per dose was simple to perform and was required only once every 3-4 weeks. Both ethiodol and the drug accumulated more selectively in tumor than in any other tissues and their activity remained for more than 3 weeks. Only minimal side-effects were associated with SMANCS and ethiodol during this study.

Adult↗
PubMed1983

Isolation and characterization of nucleases from a clinical isolate of Serratia marcescens kums 3958.

Two new extracellular nucleases, nucleases SM1 and SM2, were purified from the culture fluid of S. marcescens kums 3958, a fresh clinical isolate. The purification was carried out by the following steps; ammonium sulfate precipitation, and DEAE-cellulose and Sephadex G-100 column chromatography. At the final step, nucleases SM1 and SM2 were purified about 3,700- and 1,000-fold, respectively. They were free from phosphomonoesterase and phosphodiesterase activities. The pIs were 8.1 and 7.5 for nucleases SM1 and SM2, respectively. The molecular weight was estimated to be 35,000 for both enzymes by SDS-polyacrylamide disc gel electrophoresis. The results of amino acid analyses showed that both the threonine and serine contents were higher in nuclease SM2 than in SM1. Furthermore, nuclease SM1 was more stable than nuclease SM2 at 4 degrees C. The other properties of the two enzymes were similar; pH optimum (8.0), Mg2+ or Mn2+ for activation, and inhibition by chemical reagents such as EDTA and pyrophosphate. No significant difference was found in base specificity between nucleases SM1 and SM2. Both enzymes specifically degraded double-stranded homopolymers, especially poly(I). poly(C), as well as yeast RNA and calf thymus DNA. They hardly degraded, however, single-stranded homopolymers such as poly(dA), poly(G), and poly(U).

Amino Acids↗
PubMed1983

Immunohistochemical demonstration of proteoglycans in the skin of patients with systemic sclerosis.

Skin proteoglycan was demonstrated by an immunofluorescent technique using an antibody against bovine cartilage proteoglycan, after the cross-reactivity of human proteoglycan with the antiserum had been confirmed. Normal skin exhibited specific fluorescence mainly in the blood vessels as well as in the subepidermal area. The clinically uninvolved skin of systemic sclerosis (SS) revealed no features different from those of normal skin. However, the vascular proteoglycan deposition of early systemic sclerosis was later replaced by deposition between the collagen fibres, which appeared to progress centrifugally in parallel to the increase in the skin sclerosis, suggesting a vascular initiation of the skin lesion. Sclerotic skin was characterized by random deposition between the collagen fibres. Immunoelectron microscopic studies suggested that the random proteoglycan deposition reflected uncontrolled local accumulation of proteoglycan in the interfibrillar matrix around irregularly arranged collagen fibrils.

Adult↗
PubMed1983

Early stage of development of transplacentally induced glioma with ethylnitrosourea in rats. Sequential historadioautographic and electron microscopic studies.

Proliferative activity of possible preneoplastic cells (subependymal cells and glioblasts), early neoplastic cells and glioma cells induced by transplacental ethylnitrosourea (ENU) treatment in the rat was analysed by historadioautography and electron microscopy. Labeling index of 3H-thymidine in subependymal cells was the highest in the cerebrum of postnatal age, but no difference was observed between the normal and ENU treated groups. Thus, preneoplastic cells could not be distinguished from normal cells by morphology and proliferative activity. Focus of early neoplastic proliferation was composed of rather heterogenous and less differentiated cells, such as oligodendroblast-, glioblast- and subependymal cell-like cells, and preferentially located around the periventricular areas. Labeling index of early neoplastic proliferation was very low although the value gradually increased with age. Proliferative activity of glioma cells was higher than that of the early neoplastic cells and lower than subependymal cells, and further differed according to the degree of differentiation and morphological type. Finally, it is suggested that glioma might develop mainly through the differentiation from the focus of early neoplastic proliferation.

Animals↗
PubMed1983

Pulmonary blood flow distribution measured by radionuclide-computed tomography.

Distributions of pulmonary blood flow per unit lung volume were measured with subjects in the prone, supine, and sitting positions by means of radionuclide-computed tomography of intravenously administered 99mTc-labeled macroaggregates of human serum albumin. The blood flow was greater in the direction of gravity in all 31 subjects except one with severe mitral valve stenosis. With the subject in a sitting position, four different types of distribution were distinguished. One type had a three-zonal blood flow distribution as previously reported by West and co-workers (J. Appl. Physiol. 19: 713-724, 1964). Pulmonary arterial pressure and venous pressure estimated from this model showed reasonable agreement with pulmonary arterial pressure and capillary wedge pressure measured by Swan-Ganz catheter in 17 supine patients and in 2 sitting patients. The method makes possible noninvasive assessment of pulmonary vascular pressures.

Adult↗
PubMed1983

Mechanism of hematuria in glomerular disease. An electron microscopic study in a case of diffuse membranous glomerulonephritis.

From an electron-microscopic study in a case of diffuse membranous glomerulonephritis, we would like to propose a possible mechanism of hematuria in glomerular disease. There are several factors we should consider: (1) the deforming force of the red blood cell (RBC); (2) the deformability of the RBC; (3) the size of the gaps in the glomerular basement membrane (GBM), and (4) the thickness of the GBM. The deforming force is due to increased capillary pressure in the glomerulus that alters the contour of the RBCs. If these gaps are larger than 0.25 micron, the stretching and retracting force of the internal chamber of the GBM, combined with the capillary pulse, cause the deformed RBCs to pass through the gaps and proceed to the urinary space.

Adult↗
PubMed1983

[Intra-arterial injection of an oily antineoplastic agent in hepatic cancer].

A lymphographic agent, Ethiodol, injected via the hepatic artery was found to remain selectively in the tumor vessels of hepatoma for a long time in our clinic. Taking advantage of this selective continuous peripheral embolization, a lipophilic high molecular anticancer agent, SMANCS (Copolymer of styrene maleic acid conjugated to Neocarzinostatin) dissolved in Ethiodol was administered via the celiac axis or the hepatic artery with Seldinger's method. Anticancer effect was examined by histological findings of specimens removed using hepatic resection (13 cases) and autopsy (1 case) in 14 patients receiving this treatment. Anticancer effect of this treatment became clear through histological findings. In the patients administered SMANCS more than 0.26 mg per 1 cm2 of maximum cut-surface area, complete or widespread necrosis of the tumor occurred, whereas non-cancerous liver tissue remained unaffected.

Adult↗