Biomedical subjects

Y Tanimoto

Publications and source records attributed to Y Tanimoto.

At least 55 records · Page 3Linked to original sources

PubMed1995

[Clinical study of bronchial asthma in adult, intractable asthmatics after introduction of guideline therapy].

Introduction of Guideline for asthma treatment proposed by the committee of Japanese allergology have a tremendous impact on patients with bronchial asthma. Intractable asthmatics who have had to take some oral steroid to overcome disease severity, may have also some merit by this treatment, so that some of them might be no longer considered as intractable asthmatics. To clarify this, multicenter study was conducted. In this study, a case who have had more than 5 mg of prednisolone and/or 800 mu g of beclomethasone dipropionate throughout the year, was diagnosed as intractable asthmatics. In 845 case, 14.7%, 123 cases were diagnosed as intractable. These cases were significantly to be non-atopic and adult onset. Also, they have a significant tendency to be deteriorated by infection and careless drug administrations. Using the multiquantification method to examine the most powerful factor on intractable asthmatics, type of asthmatics was the most important and the past history of severe attack was the second. When intractable asthmatics diagnosed mainly by their BDP usage (BDP-intractable) were compared with intractable diagnosed by oral PSL (PSL-intractables), BDP-intractables were significantly atopic compared to PSL-intractables.

Asthma↗

PubMed1994

Sodium benzylideneascorbate induces apoptosis in HIV-replicating U1 cells.

U1 cells, a subclone of U937 cells chronically infected with human immunodeficiency virus type 1 (HIV-1), produced HIV-1 only in the presence of inducers such as 12-O-tetradecanoxylphorbol 13-acetate (TPA) or tumor necrosis factor (TNF)-alpha. The expression of HIV-antigen on U1 cells induced by TPA or TNF-alpha was found to be prevented by sodium 5,6-benzylidene-L-ascorbate (SBA) in a concentration-dependent manner. Treatment of U1 cells with SBA in the presence of inducers resulted in cell death with cell shrinkage, chromatin condensation and DNA fragmentation into nucleosomal oligomers, characteristics of apoptosis. In contrast, SBA had scarcely any apoptotic effect on U1 cells in the absence of inducers. SBA did not also induce apoptosis in parental U937 cells in the presence or absence of inducers. These results suggest that HIV-replicating U1 cells selectively undergo apoptosis on treatment with SBA.

Antiviral Agents↗

PubMed1994

Left ventricular motion after bypass operation for coronary artery disease with collaterals.

Left ventricular ejection changes obtained from left ventricle roentgenograms were analyzed before and after coronary artery bypass grafting in 22 consecutive patients with chronic obstructive left anterior descending coronary artery disease receiving collaterals before surgical revascularization. The collateral vessels all disappeared after surgical revascularization. After operation, ejection changes of anterobasal, anterolateral and apical walls supplied by the left anterior descending coronary artery improved from 43.6% +/- 9.7% to 48.5% +/- 8.6% (p < 0.05), from 35.2% +/- 10.9% to 39.4% +/- 9.5% (p < 0.05), and from 46.0% +/- 10.6% to 50.0% +/- 8.7% (p < 0.05), respectively. The improvement in left ventricular wall motion did not appear to be related to the extent of preoperative collateralization. Thus, left ventricular wall motion was impaired in the area supplied by collaterals and was improved by myocardial revascularization. These results suggest that coronary blood flow, even through well-developed collaterals, may not be sufficient, which may produce chronic active ischemia and impaired left ventricular wall motion.

Aged↗

PubMed1994

Anaerobic degradation of methylmercaptan and dimethyl sulfide by newly isolated thermophilic sulfate-reducing bacteria.

The complete oxidation of methylmercaptan (MSH) and dimethyl sulfide (DMS) with sulfate or nitrate as electron acceptors was observed in enrichment cultures and dilution series using thermophilic fermentor sludge as the inoculum. Three new strains of thermophilic sulfate reducers were isolated in pure culture (strains MTS5, TDS2, and SDN4). Strain MTS5 grew on MSH and strain TDS2 grew on DMS whereas strain SDN4 grew on either MSH or DMS. The cellular growth yields were 2.57 g (dry weight)/mol of MSH for strain MTS5 and 6.02 g (dry weight)/mol of DMS for strain TDS2. All strains used sulfate, sulfite, or thiosulfate as electron acceptors, but only strain SDN4 used nitrate. DMS and MSH were oxidized to CO2 and sulfide with either sulfate or nitrate as the electron acceptor. Sulfate was stoichiometrically reduced to sulfide while nitrate was reduced to ammonium. All strains were motile rods, required biotin for growth, lacked desulfoviridin, had DNA with G+C contents of 48 to 57 mol% and probably belonged to the genus Desulfotomaculum. This is the first report of the oxidation of MSH and DMS by pure cultures of sulfate-reducing bacteria.

Anaerobiosis↗

PubMed1993

Benzylideneascorbate induces apoptosis in L929 tumor cells.

Sodium 5,6-benzylideneascorbate (SBA), which is known to be an antitumor substance, was found to induce apoptotic cell death of L929 tumor cells directly in a concentration- and time-dependent manner. The dying cells exhibited cell shrinkage, disappearance of cell surface microvilli, chromatin condensation and DNA fragmentation into nucleosomal oligomers characteristic of apoptosis. These results indicate a possible mechanism by which SBA induces tumor regression in vivo.

Animals↗

PubMed1993

New flow cytometric method for surface phenotyping basophils from peripheral blood.

To clarify the role of basophils in the pathogenesis of allergic disease, we developed a new method for performing surface phenotyping of these cells in centrifugation-enriched mononuclear cell fraction. This method identified basophils on the basic of a negative reactivity with mixed FITC-conjugated monoclonal anti-bodies (mAbs) (anti-CD2, -CD14, -CD16, and -CD19) with analysis performed by flow cytometry. The validity of this approach was confirmed by sorting experiments. Various PE-conjugated mAbs were also used to examine binding to FITC-negative basophils. Basophils from asthmatic patients (n = 14) as well as from normal subjects (n = 6) were shown to express CDw32 (Fc gamma RII), CD25 (IL-2R), but not CD64 (Fc gamma RI). We also detected binding of IgG1 and IgG4 to basophils. This method of phenotyping was very rapid and simple. It thus appears to be useful in the study of allergic disease, as well as of the biology of the basophil.

Antibodies, Monoclonal↗

PubMed1993

[Flow cytometry study on purification of human eosinophils and cell function].

The eosinophil is a well-known leukocyte acting as an effector cell in the allergic reaction mechanism. The application of appropriate materials has led to more exact results from allergic examinations. In an effort to further improve analysis, we established a novel purification method for eosinophils using the flow cytometry (PCM) of peripheral blood and bronchoalveolar lavage fluid (BALF) leucocytes from healthy and allergic subjects. We examined the function of these cells in chemotaxis by platelet activating factor (PAF) and recombinant human (rh) IL-5. We obtained following results. First, we were able to separate human eosinophils containing autofluorescence substance, which was detectable by FCM employing a 450 nm argon ion laser. Second, the purity and recovery rate of the eosinophils were 90.1 +/- 4.2% and 32.1 +/- 7.6% in the healthy subjects who had no peripheral eosinophilia (< 6%) and 93.7 +/- 4.4% and 37.2 +/- 7.5% in the allergic subjects who had eosinophila (> 6%). A relationship was readily apparent between the peripheral and purified eosinophil counts in the healthy subjects (r = 0.62). Autofluorescence of the eosinophil fraction on PCM was further found to be decreased in patients with marked eosinophilia because of an increase in hypodense eosinophils. Third, highly purified eosinophils (76%) were also obtained from the 6.5% eosinophils present in the bronchoalveolar lavage fluid of one bronchial asthma patient. Fourth, the maximal chemotaxis of these eosinophils was shown at 10(-6) M of platelet activating factor (PAF) and at 1 micrograms/ml of IL-5 in a dose-dependent manner. This activity in allergic patients was accelerated compared with that in healthy subjects.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1992

Purification of human blood basophils using negative selection by flow cytometry.

Basophils were purified from peripheral blood of normal donors using Percoll discontinuous gradients and negative selection by flow cytometry. The mean purity of basophils obtained was 84.7 +/- 4.1 (s.d.)% (range 77.3-90.0%, n = 13). The overall yield of these procedures was 16.0 +/- 2.6% (range 11.0-19.9%, n = 13), and cell viability of purified basophils exceeded 90%. Properties of highly purified basophils obtained by flow cytometry did not differ from those of partially enriched basophil preparations from Percoll discontinuous gradients in respect of: (i) intracellular histamine content; (ii) percentage of spontaneous histamine release in buffer; and (iii) percentage of histamine release triggered by ionophore A 23187 or anti-IgE. Moreover, purified basophils responded chemotactically to complement C5a in a dose-dependent manner. These findings suggest that our procedure for purification of human basophils does not affect the functions of basophils and may be useful for in vitro studies on the role of basophils in hypersensitivity reactions such as bronchial asthma.

Basophils↗

PubMed1992

Effects of cytokines on human basophil chemotaxis.

Basophil chemotactic activity (BCA) of eight recombinant human (rh) cytokines was examined. Highly purified basophils were obtained by Percoll discontinuous gradients, followed by negative selection using flow cytometry. Then BCA was measured by means of modified Boyden chamber method. Both interleukin (IL)-3 and granulocyte-macrophage colony-stimulating factor (GM-CSF) had much more potent BCA than complement C5a, leukotriene B4 and platelet activating factor, well known as granulocyte chemotactic factors. Chemotaxis rather than chemokinesis was shown in chequerboard analysis of basophil migration induced by IL-3 and GM-CSF. Relatively high concentrations of IL-5 also induced basophil migration, although predominantly chemokinetic. IL-8 had apparent BCA, which was not so high as that of C5a. In contrast, IL-2, IL-4, interferon(IFN)-gamma and granulocyte colony-stimulating factor (G-CSF) had no significant BCA. These findings suggest that IL-3, IL-5, GM-CSF and, perhaps, IL-8 have an effect on basophil migration as well as modulation of basophil mediator release and may provide some insight into the basophil accumulation observed in late-phase allergic responses.

Basophils↗

PubMed1992

[The influence of serum separators on biochemical values in experimental animals].

The influence of three serum separators, A, B and C, on biochemical values was examined. With A or B, changes in the values of ChE, LAP, UN, K, P, Cl and Ca in rat serum; ChE, UN, Cl and Ca in dog serum; and K and P in monkey serum took place over a period of 20 min after blood collection. Therefore, the biochemical values of whole blood were considered to be stable after 20 min. Thus, biochemical tests were conducted on serum from the three serum separators after allowing the blood to stand 20 min. The values obtained for each separator were not markedly different from those of the control. These results suggest that a serum separator is useful for separation of serum of experimental animals under the proper conditions.

Animals↗

PubMed1992

[The reactivity of dispersed human lung mast cells and peripheral blood basophils to acetylcholine].

To clarify the relation between human lung mast cells and parasympathetic nerve function as well as IgE mediated allergic reactions, highly purified dispersed human lung mast cells were obtained by using the techniques of scissors dispersion, enzymatic treatment, percoll centrifugation and exclusion of adherent cells. The reactivity to acetylcholine was examined by observing the histamine release of purified mast cells. Moreover, peripheral blood basophils, which have many functional similarities with mast cells, were also examined in the same manner. The following results were obtained; 1) Histamine was significantly released from dispersed human lung mast cells at a final concentration of 10(-5) M acetylcholine (p less than 0.05); the peak of histamine release was 10(-4) M of acetylcholine. Acetylcholine had the additional effect of releasing histamine in response to anti-IgE. Histamine release was partially inhibited by 10(-5) M atropine. 2) Basophils had no response to acetylcholine. These results suggest that human lung mast cells play an important role in the defensive mechanism as an effector cell of acetylcholine-mediated autonomic nerve system as well as IgE-mediated allergic reaction.

Acetylcholine↗

PubMed1992

[Left ventricular approach for muscular ventricular septal defects in infant].

Two infants less than 4 months of age underwent repair of apical muscular VSD with left ventriculotomy. First case was 3 months old boy who had already undergone enlargement of the hypoplastic aortic arch with subclavian flap aortoplasty and pulmonary artery banding because of the associated aortic coarctation. Second case was 4 months old Down syndrome girl who associated with ASD and PDA. Both infants were diagnosed the apical muscular VSD with echocardiography and left ventriculography. We performed short longitudinal left ventriculotomy which was parallel to the left anterior descending coronary artery between the diagonal branch and left circumflex artery. VSD was closed with Gore-Tex patch using 6-0 prolene buttress stitches. Post operative echocardiography showed good LV contractile function (Ejection Fraction = 71%, 80%), and no residual interventricular shunt. Left ventriculotomy for the apical VSD closure allowed good exposure and did not reduce the LV function even in infants. Therefore, we concluded that left ventriculotomy was an useful procedure for the apical muscular VSD in infants.

Cardiac Surgical Procedures↗

PubMed1992

[Studies of lymphocyte activation on late asthmatic response in adult asthma].

Late asthmatic response (LAR) as well as delayed asthmatic response (DeAR) is an important clinical characteristic in adult severe asthma. These responses might be based on cell to cell interaction following lymphocyte activation. Therefore, to clarify the pathogenesis of LAR, we studied the lymphocyte functions of adult asthmatics with LAR provoked by inhalation of house dust and Candida antigen. The results revealed that mite antigen-specific lymphocyte blastogenesis, IL-2 and ECF production were significantly higher in asthmatics with LAR provoked by house dust antigen than in normal subjects and asthmatics with IAR by house dust and LAR by Candida, though there was no significant difference in NCF. Candida antigen-specific lymphocyte blastogenesis, IL-2, ECF and NCF production were significantly higher in asthmatics with LAR provoked by Candida antigen than in normal subjects and asthmatics with IAR or LAR provoked by house dust. There was a positive correlation between Candida antigen-specific IL-2 and NCF production in asthmatics with LAR provoked by Candida antigen. These results suggest that antigen-specific lymphocyte activation may play an important role in the pathogenesis of LAR, especially in asthmatics with LAR provoked by Candida antigen, and that LAR and DeAR should be considered inclusively as cell-mediated allergy.

Adolescent↗

PubMed1992

[Purification and reactivity of human lung mast cells].

To clarify the pathogenesis of allergic pulmonary diseases by analysis of the reactivity of human lung mast cells, we established a method of dispersion and purification of mast cells from human lung tissue. This method consisted of 4 steps; 1) mincing by scissors, 2) enzymatic treatment by a pronase-chymopapain and collagenase-elastase mixture, 3) percoll centrifugation and 4) exclusion of adherent cells. Using this method, dispersed human lung mast cells were obtained with 38.8% purity and more than 95% viability. These mast cells contained 4.1 pg of histamine per cell, which showed these cells had mild spontaneous histamine release after treatment. The mast cells released histamine in a dose-dependent manner after treatment with calcium ionophore A 23187 and anti-IgE, and these phenomena were dependent on extracellular calcium ions. However, the cells did not release histamine with less than 100 micrograms/ml of compound 48/80. These results indicate that the human lung mast cells obtained by this method are useful to make immunological and pharmacological analyses in allergic lung diseases.

Humans↗

PubMed1991

A constitutive form of guinea pig liver cytochrome P450 closely related to phenobarbital inducible P450b(e).

In order to provide evidence that a cytochrome P450 belonging to the IIB subfamily is expressed as a constitutive form in the guinea pig, we tried to purify an isozyme from liver microsomes of untreated guinea pigs by assessing its reactivity with anti-P450b antibody in the present study. One form of cytochrome P450, named P450GP-1, was obtained. The minimum molecular weight of this isozyme was estimated to be 52,000 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The amino terminal sequence up to the 33rd amino acid of P450GP-1 was determined. As expected, comparison of the amino acid sequence with those of cytochrome P450 isozymes from other species reported so far indicated that P450GP-1 was highly homologous to P450s categorized in the IIB subfamily; that is, 67% similarity to rat P450b, 82% to rabbit LM2, 76% to dog PBD-2, 70% to mouse pf 3/46, and 73% to human IIB1. On the other hand, P450GP-1 showed only low similarity, less than 41%, to other cytochrome P450s of the II subfamily and those of the I, III, and IV families. Affinity of P450GP-1 to anti-P450b immunoglobulin G was confirmed to be comparable with that of a principal antigen, P450b. Immunoblot analysis revealed that P450GP-1 in the guinea pig liver microsomes was induced by phenobarbital treatment, but the increase was not as large as in the rat. P450GP-1 efficiently catalyzed benzphetamine N-demethylation, strychnine 2-hydroxylation, and testosterone 16 beta-hydroxylation, all of which are also catalyzed by P450b. Based on these results, it was strongly suggested that the IIB-type of cytochrome P450 in guinea pigs, at least one of them, is a constitutive form which is moderately induced by phenobarbital.

Amino Acid Sequence↗

PubMed1991

Analysis of two-dimensional electrophoretic patterns of proteins obtained from the sera of normal and tumor-bearing nude rats.

To classify two-dimensional electrophoresis (2-DE) patterns of normal and abnormal samples, a new parameter, named shift value, is introduced. The shift value is defined by the product of three indices; differences in density, differences in area, and the Euclid distance between peaks of matched glycoprotein spots in the 2-DE patterns. Shift values obtained from the differences between the 2-DE patterns of tumor-bearing and normal sera (control) were always found to be larger than those obtained from two control patterns. The shift value obtained from glycoprotein spots could be more effectively used to distinguish normal and abnormal patterns than that obtained from simple proteins. In our earlier attempts to compare serum proteins of normal and tumor patients, we could not discriminate differences caused by genetic background. In order to circumvent this difficulty, we employed an inbred strain of nude rats into which various types of human cancer had been implanted. Reliability of the analysis is enhanced by using a polyacrylamide gel backed with a silanized glass support and an automatic 2-DE apparatus.

Animals↗

PubMed1991

Site-selective oxidation of strychnine by phenobarbital inducible cytochrome P-450.

The metabolism of strychnine was studied using liver microsomes of rats treated with phenobarbital or 3-methylcholanthrene (MC). The phenobarbital-treatment resulted in 7.9-fold and 4.8-fold increases in 2-hydroxylation and N-oxidation of strychnine, respectively. The formation of 16-hydroxystrychnine, strychnine 21,22-epoxide and 22-hydroxystrychnine was induced about 2-fold. MC-treatment resulted in only 1.4-fold induction of each oxidation activity. In addition, strychnine 2-hydroxylation activity was markedly induced in liver microsomes of phenobarbital-treated mice, guinea pigs, rabbits and dogs (2.5-10.5-fold). Induction of N-oxidation activity was also higher than that of the three other oxidation activities. A reconstituted system of strychnine metabolism using cytochrome P-450 isozymes, P-450I (P450IIB1) and P-450II (P450IIB2), purified from liver microsomes of phenobarbital-treated rats showed significantly high and selective activities towards 2-hydroxylation and N-oxidation of strychnine. This characteristic metabolism of strychnine appears to occur in common with interspecies P450IIB gene subfamily. The pH Optima of 2-hydroxylation and N-oxidation of strychnine were between 8.4 and 8.6 in the microsomes of phenobarbital-treated rats, while that of N-demethylation of benzphetamine, a typical substrate of phenobarbital-inducible cytochrome P-450, was between 7.4 and 7.6. In a reconstituted system with P-450I, strychnine oxidation was little affected by pH change, while benzphetamine N-demethylation activity was decreased in the alkaline side. Among several oxidations tested, only ethylmorphine N-demethylation underwent the same pH effect as did strychnine oxidation with the microsomes and reconstituted system.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1991

A novel metabolite of strychnine, 22-hydroxystrychnine.

1. An unknown metabolite of strychnine termed M-5 was isolated, from an incubation mixture using guinea pig liver microsomes, by repeated preparative t.l.c. 2. The structure of M-5 was shown to be 22-hydroxystrychnine by mass, n.m.r. and i.r. spectrometry. 3. 22-Hydroxystrychnine is a stable enol, a unique metabolite possessing a hydroxyl group on the double bond of the alicylic moiety.

Animals↗