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Biomedical subjects

T Shida

Publications and source records attributed to T Shida.

At least 145 records · Page 8Linked to original sources
PubMed1989

A case of postnephrectomy arteriovenous fistula.

A rare case of a postnephrectomy arteriovenous fistula involving the major renal vessels is presented herein. This type of postnephrectomy arteriovenous fistula is very unusual; in fact, since first documented in 1934, only 65 cases have been reported in the world literature, including 2 cases from Japan. Even though postoperative arteriovenous fistulae are rare, one should bear this complication in mind when unknown causes of bruit or heart failure develop following surgery.

Aorta, Abdominal↗
PubMed1989

Quantitation of platelet-activating factor by high-performance liquid chromatography with fluorescent detection.

Platelet-activating factors, 1-O-hexadecyl- and 1-O-octadecyl-2-acetyl-sn-glycero-3-phosphocholine (C16-AGEPC and C18AGEPC), were measured by reverse-phase high-performance liquid chromatography with fluorescent detection. C16AGEPC, C18AGEPC, and 1-O-hexadecyl-2-propionyl-sn-glycero-3-phosphocholine, which was suitable for use as an internal standard, were hydrolyzed with phospholipase C, and then the resulting hydrolyzed products were derivatized with 7-methoxycoumarin-3-carbonyl chloride or 7-methoxy-coumarin-4-acetic acid to form 7-methoxycoumarin ester derivatives which permit a fluorometric detection. The lower limit of detection of the derivatives was about 100 pg at a signal-to-noise ratio of 5:1. A commercial platelet-activating factor was demonstrated to contain C16AGEPC (70%) and C18AGEPC (12.8%) by the present method. The present method was also applicable to the measurement of acetyl-CoA:1-alkyl-2-lyso-sn-glycero-3-phosphocholine acetyltransferase activity in a lysate of human polymorphonuclear leukocytes.

Acetyltransferases↗
PubMed1989

Comparative analysis of physicochemical and immunochemical properties of the two major allergens from Dermatophagoides pteronyssinus and the corresponding allergens from Dermatophagoides farinae.

Two major allergens, DP1 (Der p I) and DP2 (Der p II), were isolated from the whole culture extract of Dermatophagoides pteronyssinus, and the physicochemical and immunochemical properties of these allergens were compared with those of the corresponding allergens from Dermatophagoides farinae, DF1 (Der fI) and DF2 (Der fII). On sodium dodecyl sulfate-polyacrylamide gel electrophoresis, polyacrylamide gel isoelectric focusing and amino acid analysis, both DP1 and DP2 were demonstrated to have close physicochemical similarity with DF1 and DF2, respectively. On immunodiffusion with the use of rabbit antisera, the two Der I allergens showed the reaction of typical partial identity, while the two Der II allergens showed the reaction of almost complete identity. Radioallergosorbent test (RAST) and RAST absorption experiments with the use of sera from mite-allergic patients showed that human IgE antibody response to the Der I allergens was directed against both cross-reactive and species-specific determinants. In contrast, IgE antibodies to the Der II allergens were demonstrated to react almost completely to cross-reactive determinants.

Allergens↗
PubMed1989

Measurement of allergens associated with dust mite allergy. I. Development of sensitive radioimmunoassays for the two groups of Dermatophagoides mite allergens, Der I and Der II.

Sensitive radioimmunoassays were developed to measure the two groups of major allergens (Der I and Der II) of Dermatophagoides pteronyssinus and Dermatophagoides farinae, in which radiolabeled protein A served as a general tracer. Glass rods covalently coupled with F(ab')2 fragments of rabbit antiserum IgG were incubated first with mite or house dust extracts, and then with affinity-purified rabbit antibodies. The bound allergen-antibody complex was detected with a 125I-labeled protein A. The two Der I allergens, Der p I and Der f I, were measured separately with the use of immunoabsorbed rabbit antibodies directed against species-specific determinants, while the two Der II allergens, Der p II and Der f II, were measured as 'Der II' with the use of antibodies directed against common determinants on both allergens. Each assay demonstrated consistently parallel dilution curves with mite and house dust extracts. The mean intraassay and interassay coefficient of variation for each assay ranged from 4.3 to 7.7% and from 3.6 to 9.0%, respectively. The Der p I and Der f I assays were shown to be highly species-specific so that the ratio of Der p I: Der f I would provide a good index of the distribution of the two mite species in a dust sample. The concentrations of the Der I and Der II allergens in different types of mite extract and dust samples from houses were compared using these assays.(ABSTRACT TRUNCATED AT 250 WORDS)

Allergens↗
PubMed1989

Measurement of allergens associated with dust mite allergy. II. Concentrations of airborne mite allergens (Der I and Der II) in the house.

Assays of mite allergens (Der p I, Der f I and Der II) in the air of houses became feasible with the use of a low-noise air sampler and a sensitive radioimmunoassay described previously. The levels of the airborne allergens Der I (Der p I + Der f I) and Der II in the living room of 10 houses during usual domestic life were very low, 29.5 and 6.3 pg/m3, respectively, with a Der I: Der II ratio of 4.7:1. At the time of bedmaking, they greatly increased, about 1,000-fold, to 30,900 and 12,600 pg/m3, respectively, with a Der I: Der II ratio of 2.5:1. The amounts of Der I and Der II in the floor dust of the living room were 2,040 and 2,690 ng/g of fine dust, respectively, with a Der I: Der II ratio of 0.8:1. Der I seemed more prone to become airborne than Der II.

Air↗
PubMed1989

[The role of prostaglandin I2 in heart transplantation under deep hypothermia].

The role of Prostaglandin I2 (PGI2) on heart transplantation under deep hypothermia were investigated using 25 weighing an average of 5 kg. They were put to deep hypothermia by surface cooling with either anesthesia until rectal temperature reached 18 degrees C. Then the heart was arrested with cardioplegic solution, removed and re-transplanted. They were divided into 2 groups according to the usage of PGI2, i.e., non PGI2 group (n = 12) and PGI2-treated group (n = 13). In PGI2-treated group, PGI2 was administered intravenously 1 micrograms/kg/min during cooling and rewarming periods, and was added 500 ng/ml into cardioplegic solution. In the last 13 dogs (7 dogs in non PGI2 group and 6 dogs in PGI2 group) about which left ventricular functions were mainly examined, topical cooling of the myocardium was omitted. Results were as follows; compared with non PGI2 group, PGI2-treated group showed significantly higher cooling and rewarming rates, more rapid recovery of cardiac output after transplantation, and lower systemic vascular resistance throughout the experimental period. Left ventricular functions after resumption of heart beats were better in PGI2-treated group than in non PGI2 group. Microscopic examinations of the heart revealed that ischemic changes of myocardial cells were less prominent in PGI2-treated group than in non PGI2 group. It is concluded that PGI2 is useful additive for heart transplantation under deep hypothermia in that it could shorten operative time due to quicker control of the body temperature with rather stable haemodynamics and also it might protect myocardium during ischemia.

Animals↗
PubMed1989

Self-assembly of synthetic deoxyoligonucleotides containing d-G clusters.

Deoxyoligonucleotides containing d-G cluster were synthesized to elucidate exact structures and properties of the parallel-four stranded complexes of oligo(dG). Among these oligomers, d-TTGGGGTT and d-TTGGGGGGTT formed stable complexes which were able to interact with ethidium bromide known as an intercalator.

Electrophoresis, Polyacrylamide Gel↗
PubMed1989

[Measurement of IgE, IgG1 and IgG4 antibodies against mite Sephadex fractions and purified allergens by means of enzyme-linked immunosorbent assay].

Mite antigens (Dermatophagoides farinae) were fractionated by a Sephadex G-200 column and their reactivities with IgE, IgG1 and IgG4 antibodies were investigated with enzyme-linked immunosorbent assay (ELISA). High IgE antibody values were observed in fractions with low molecular weight (allergenic part), while high IgG1 and IgG4 antibody values were observed in fractions with high molecular weight. High IgG4 antibody values to crude mite extract and fractions with high molecular weight were detected in individuals who had received immunotherapy. However, IgG4 antibodies directed to allergenic part were found in only one out of 12 sera tested. IgG4-ELISA using DF1 (major allergen of Dermatophagoides farinae) as antigen was also performed. In the group treated with mite, significant IgG4 antibody levels were detected in only one out of 13 sera tested. In the group treated with house dust, significant IgG4 antibodies were detected in only one out of 12 sera tested. Patients who showed high IgG4 antibody responses to crude mite extract and to high molecular weight did not show responses to allergenic part and DF1. The only case who showed positive IgG4 responses to allergenic part also reacted with DF1. Those results suggest that IgG1 and IgG4 antibody values in ELISA using crude mite extract as antigen do not reflect major allergen-specific antibody values. The importance of the use of partially purified antigens in measuring major allergen-specific IgG4 antibodies was also suggested.

Allergens↗
PubMed1989

The causes and value of hyperphosphatemia in experimental strangulation obstruction.

In model experiments with mongrel dogs, intestinal strangulation obstruction was induced by occluding the superior mesenteric veins, and a rise in the inorganic phosphate value of the blood was observed. The high inorganic phosphate values of the fluid exuding from the strangulated bowel suggest that intestinal factors associated with the strangulated bowel may be partly responsible for this elevated phosphatemia. However, hyperphosphatemia was also found in a model experiment in which the route through which the fluid was absorbed into the blood from the peritoneal cavity was interrupted by keeping the strangulated bowel in an intestinal bag. After this, in the model experiments in which a systemic blood pressure depression curve with a percentage reduction similar to that of the decreasing arterial blood pressure resulting from strangulation was produced (by exsanguination, and even by exsanguination with adequate perfusion of the gut), plasma inorganic phosphate values also increased. Therefore it is undeniable that systemic factors other than the above-mentioned local factors are related to the rise in plasma inorganic phosphate values in experimental strangulation obstruction. Because it is not possible to assert that phosphatemia is specific to intestinal strangulation, the importance of a rise in inorganic phosphate values in the early diagnosis of intestinal strangulation cannot be considered very great.

Animals↗
PubMed1988

Isocratic determination of arachidonic acid 5-lipoxygenase products in human neutrophils by high-performance liquid chromatography.

A high-performance liquid chromatographic method was developed to determine arachidonic 5-lipoxygenase products in calcium ionophore-stimulated neutrophils. This procedure allows the simultaneous measurement of leukotriene B4 (LTB4) and its omega-oxidation products without using a gradient elution system. 20-Carboxy-LTB4, 20-hydroxy-LTB4, 6-trans-LTB4, 12-epi-6-trans-LTB4, LTB4 and 5s,12s-dihydroxyeicosatetraenoic acid can be separated and quantitated by reversed-phase chromatography using isocratic elution. The generation and degradation of 5-lipoxygenase products by human neutrophils following stimulation with calcium ionophore have been examined by this method.

12-Hydroxy-5,8,10,14-eicosatetraenoic Acid↗
PubMed1988

Effect of deuterium oxide on leukotriene C4 generation in immunologically stimulated human leukocytes.

Addition of deuterium oxide (D2O), 6-36%, resulted in a dose-dependent increase in allergen- or anti-IgE-induced leukotriene C4 (LTC4) generation from human basophils. In the presence of 36% D2O, the enhancement was 260 +/- 135% for allergen stimulation and 480 +/- 152% for anti-IgE stimulation as compared with the control incubated in normal buffer. The increasing effect of D2O on LTC4 generation from basophils was completely reversed by washing the cells before incubation with allergen. Vinblastine as well as colchicine, at a concentration of 100 microM, counteracted the effect of D2O. The enhanced release of histamine and LTC4 from basophils challenged with allergen was suppressed by Dimaprit, a histamine H2 receptor agonist, at a concentration required to inhibit the release by 50% of 5 X 10(-5) M for histamine and 10(-5) M for LTC4. These observations suggest that microtubules may be involved in LTC4 generation from immunologically stimulated basophils.

Basophils↗
PubMed1988

Augmentation of leukotriene C4 production by gamma interferon in leukocytes challenged with an allergen.

Leukocytes from mite-sensitive asthmatic patients were challenged with an allergen and the supernatant assayed for histamine, immunoreactive leukotriene C4 (i-LTC4), and gamma-interferon (gamma-IFN). In addition, the concentration of gamma-IFN in the plasma of patients with bronchial asthma was assayed. Significantly higher concentrations (p less than 0.01) of gamma-IFN were detected in patients' plasma (0.27 +/- 0.32 U/ml, n = 61) than in that of healthy controls (0.04 +/- 0.06 U/ml, n = 19). The leukocytes produced 7.3 +/- 6.7 ng of i-LTC4/10(6) basophils (n = 32), and histamine release was 41.1 +/- 37.1% of total histamine. There was a significant correlation (p less than 0.01) between the capacity of leukocytes to release i-LTC4 and gamma-IFN. The capacity of leukocytes to release histamine and to produce gamma-IFN was not significantly correlated (r = 0.263). About twice as much i-LTC4 was generated from leukocytes pretreated for 24 h with 0.1-1.0 U/ml of recombinant human gamma-IFN, but histamine release was not changed. Another type of IFN, alpha-IFN, did not alter the capacity of leukocytes to release histamine as well as gamma-IFN upon preincubation for 24 h at 1-1,000 U/ml. Pretreatment with 1-10 U/ml of beta-IFN slightly enhanced the capacity upon challenge with 10 ng/ml of mite allergen. The enhancing effect of gamma-IFN on i-LTC4 generation was decreased by treatment with H-7, a nonspecific inhibitor of protein kinase C activity.(ABSTRACT TRUNCATED AT 250 WORDS)

Adjuvants, Immunologic↗
PubMed1988

[Antiallergic effects of mequitazine. 1. In vitro experiments].

The antiallergic effects of 10-(3-quinuclidinylmethyl)phenothiazine (mequitazine) were investigated in vitro. The results obtained were as follows: 1) In the isolated trachea and lung parenchyma of guinea pigs, mequitazine showed a fairly potent antagonistic action against contractions induced by both histamine (Hi) and acetylcholine (ACh). Mequitazine was much less potent in antihistaminic action and slightly more potent in anticholinergic action than ketotifen. The contractions of the preparation by leukotriene (LT) D4 were antagonized by mequitazine, although the potency was moderate, showing an IC50 value of 2.3 x 10(-5) g/ml in the trachea and 5.1 x 10(-5)g/ml in the lung parenchyma. Mequitazine had no effect on the contraction of the trachea by PGF2 alpha, but inhibited that of the lung parenchyma with pA2 = 7.0. 2) Mequitazine (10(-6) g/ml) slightly inhibited the Schultz-Dale reaction of the isolated guinea pig trachea, while ketotifen at the same concentration did not show any effect. 3) The contraction of the isolated guinea pig trachea by Ca2+ influx was slightly inhibited by mequitazine (10(-5) g/ml). 4) Mequitazine competitively inhibited the cyclic AMP-dependent phosphodiesterase activity from the rat lung with a potency of 10 times and 5 times more than those of ketotifen and theophylline, respectively. 5) Mequitazine (10(-6) to 10(-5) M) suppressed both the anaphylactic and phospholipase A2-induced histamine release from the peritoneal cells of rats. 6) Mequitazine (10(-5) g/ml) also inhibited the anaphylactic and Ca ionophore-induced histamine release from the leukocytes of the atopic patients and normal subjects. 7) The anaphylactic releases of histamine, LTB4 and peptide LT from the human lung fragments were dose-dependently inhibited by mequitazine (10(-7) approximately 10(-5) g/ml).

Acetylcholine↗
PubMed1988

[Antiallergic effects of mequitazine. 2. In vivo experiments].

Antiallergic effects of mequitazine were investigated in vivo and compared with those of ketotifen and disodium cromoglycate (DSCG). The results obtained were as follows: 1) Mequitazine in doses of 2 and 5 mg/kg given, p.o., 1 hr prior to antigen challenge inhibited dose-dependently the 48-hr passive cutaneous anaphylaxis in rats. Five mg/kg of mequitazine showed almost the same extent of inhibitory activity as that of 1 mg/kg of ketotifen. An i.v. administration of 1 mg/kg DSCG 1 min before antigen challenge also showed a marked inhibition. 2) The experimental asthma induced by challenge with an i.v. injection of antigen in passively sensitized guinea pigs was fairly inhibited by the pretreatment with 5 mg/kg of mequitazine administered p.o., although 2 mg/kg of this drug showed only a slight inhibition. 3) The experimental asthma induced by aerosolized antigen was also fairly inhibited by the pretreatment with 5 mg/kg of mequitazine given p.o.

Administration, Oral↗
PubMed1988

Immunopharmacological studies on TBX, a new antiallergic drug (2). Inhibitory effects on histamine release from peritoneal mast cells and lung fragments of rats.

The ability of 9-methyl-3-(1H-tetrazol-5-yl)-4H-pyrido[1,2-a]pyrimidin-4-one potassium salt (TBX) to inhibit histamine release from both peritoneal exudate cells (PEC) containing mast cells and lung fragments of rats was investigated in vitro. Low concentrations of TBX dose-dependently inhibited IgE-mediated histamine release from PEC of passively sensitized animals; its IC50 was 5.1 x 10(-9) g/ml. When TBX was added simultaneously with the antigen challenge, the highest inhibition was obtained. In contrast, extension of preincubation time with the agent resulted in a marked decrease in the inhibition of histamine release. The potent inhibition of histamine release by TBX was observed equally in glucose-free as well as complete Tyrode's solution, whereas TBX reduced its inhibitory action in Ca2+-free or D2O-supplemented medium. In addition, TBX inhibited compound 48/80- but not calcium ionophore A23187-induced histamine release from normal PEC. With regard to the intracellular cyclic AMP level in normal PEC, it was significantly enhanced by a high concentration of TBX (10(-3) g/ml). TBX also inhibited antigen-induced histamine release from lung fragments of actively immunized animals. Interestingly, TBX displayed non-competitive inhibition of cyclic AMP-dependent phosphodiesterase derived from lung homogenates; its K1 value was 8.70 x 10(-4) M.

3',5'-Cyclic-AMP Phosphodiesterases↗
PubMed1988

Immunopharmacological studies on TBX, a new antiallergic drug (1). Inhibitory effects on passive cutaneous anaphylaxis in rats and guinea pigs.

The effects of 9-methyl-3-(1H-tetrazol-5-yl)-4H-pyrido[1,2-a]pyrimidin-4-one potassium salt (TBX), a new antiallergic drug, on passive cutaneous anaphylaxis (PCA) mediated by homologous IgE or IgG antibody were investigated in rats and guinea pigs. TBX (i.v. and p.o.) clearly inhibited IgE- and IgGa-mediated homologous PCAs in rats, without showing any inhibition of the skin reactions caused by histamine, serotonin and bradykinin in contrast to the inhibition of prostaglandin E1-induced skin reaction. Neither adrenalectomy nor propranolol treatment modified TBX's inhibition of the former PCA. With regard to tachyphylaxis to TBX, it was demonstrable in IgE-mediated homologous PCA in rats when they were pretreated with TBX (0.5 mg/kg, i.v.), followed 60 min later by a second dose of the drug (0.05 mg/kg, i.v.). There was no cross-tachyphylaxis between disodium cromoglycate (DSCG) and TBX. Homologous PCA caused by guinea pig IgE was also inhibited in a dose-dependent fashion by i.v. and p.o. administrations of TBX, although higher doses of TBX were needed to inhibit guinea pig PCA than the rat one. Interestingly, TBX showed more potent inhibition of both rat and guinea pig homologous PCAs than DSCG or tranilast. The results obtained indicate that TBX is an orally effective antiallergic agent displaying no antagonistic actions on the chemical mediators released.

Animals↗