Biomedical subjects

M Takagi

Publications and source records attributed to M Takagi.

At least 667 records · Page 37Linked to original sources

PubMed1990

[Plasminogen activator in leukemic cell homogenate].

We examined fibrinolytic substances in homogenate of leukemic cells, normal granulocyte or mononuclear cells fraction. Plasminogen activators (PA) were significantly low in normal cells, but they were slightly increased in lymphoblastic leukemia cells and markedly increased in myeloblastic leukemia cells. In almost leukemic cells homogenate, the antigen ratio of tissue type PA (t-PA)/urokinase type PA (u-PA) was about 2.0. In especially AMMoL and AMoL, PA activity had discrepancy between euglobulin lysis time and amidolytic assay using chromogenic substrate. As PA inhibitor (PAI)-II was markedly increased in them. PAI might effect the PA assay. PA activity of leukemic cells homogenate was similar to that without t-PA stimulator and leukemic cells homogenate significantly stimulated t-PA. As both PA activity and antigen were statistically increased in leukemic cells homogenate of patient with disseminated intravascular coagulation (DIC), PA and PA stimulator in leukemic cell might play an important role in hypofibrinogenemia or DIC.

Afibrinogenemia↗

PubMed1990

A harvesting method of monocytes/macrophages derived from bone marrow and their characteristics--special reference to the effect of 1,25-dihydroxyvitamin D3 on monocytes/macrophages.

We have investigated the relationship between monocytes/macrophages and bone metabolism with the in vitro study. In the present study monocytes/macrophages derived from rat bone marrow were harvested and their phenotype was examined. Collected cells exhibited many characteristics of monocytes/macrophages at various points. In addition, 1,25-dihydroxyvitamin D3(D3), one of the osteotropic hormones was found to alter the activities of acid phosphatase (AcPase) and lysozyme in the media and also stimulate alkaline phosphatase (AlPase) positive cells to increase in number.

Acid Phosphatase↗

PubMed1990

[Availability of DDAVP in hemostasis control for the breast tumor resection in a patient with thrombasthenia (type II)].

We reported a 33-year-old woman with thrombasthenia (type II) in whom 1-deamino-8-D-arginine vasopressin (DDAVP) was available for the hemostasis control during breast tumor resection. She has had recurrent nasal bleeding and purpura since 2 years old. On the first admission to our hospital because of hematuria at 18 years old, she was diagnosed as thrombasthenia (type II) from hemostatic studies. At 20 years old, she had a healthy baby by the cesarean section with transfusion of fresh blood and platelet concentrates. On the 5th admission for the breast tumor resection, defect of glycoprotein II b-III a of her platelets was confirmed by using SDS gel electrophoresis. Recently, there are some reports on availability of DDAVP for hemostatic control in platelet dysfunction of various etiologies as well as mild hemophilia and von Willebrand disease. So, DDAVP (0.4 microgram/kg) was used for hemostasis control. After 1 hour, the bleeding time was shortened from over 10 to 4 min, platelet adhesiveness to glass beads increased from 1.8 to 37%. Furthermore, the levels of Ristocetin cofactor and von Willebrand factor antigen (especially large multimer) also increased. But platelet aggregation with various inducers remained unchanged before and after infusion. Breast tumor (fibroadenoma) resection.

Adult↗

PubMed1990

[Laboratory and clinical studies of norfloxacin in pediatric field].

We have carried out laboratory and clinical studies on norfloxacin (NFLX, AM-715). The results are summarized as follows. NFLX was given through oral administration to one child each at dose levels of 1.7 mg/kg, 2.4 mg/kg and 3.2 mg/kg. After administration, peak serum levels of NFLX obtained for the 3 dose levels were 0.16 micrograms/ml at 1 hour, 0.69 micrograms/ml at 2 hours, 0.81 micrograms/ml at 1 hour, respectively, and half-lives were 2.5 hours, 1.8 hours and 2.7 hours, respectively. NFLX was given through oral administration to 2 children at a dose level of 4.4 mg/kg and to another child at a dose level of 4.8 mg/kg. After administration, mean peak serum levels of NFLX obtained were 1.17 +/- 0.48 micrograms/ml and half-lives were 3.0 +/- 0.5 hours. Urinary excretion rates of NFLX were 14.5% and 28.4% in the first 8 hours after administration of 1.7 mg/kg and 3.2 mg/kg, respectively, and 29.1% in the first 6 hours after administration of 2.4 mg/kg. Mean urinary excretion rates of NFLX were 38.5 +/- 13.0% in the first 8 hours after administration of 4.4 mg/kg and 4.8 mg/kg. Treatment with NFLX was made in 33 cases of pediatric bacterial infections including 5 cases of tonsillitis, 14 cases of enteritis, 10 cases of UTI and 1 case each of bronchitis, balanoposthitis, impetigo and pustulosis. Results obtained were excellent in 14 cases, good in 15 cases. No significant side effect due to the drug was observed in any cases.

Adolescent↗

PubMed1989

Tropomyosin-caldesmon/actomyosin systems in platelets and arterial smooth muscle: results from exchange experiments.

Tropomyosin and caldesomon reciprocally control the actomyosin system in smooth muscle and some non-muscle cells. To compare this mechanism between arterial smooth muscle and platelets, we carried out extensive exchange experiments. Actin, myosin, tropomyosin from arterial smooth muscle cells and platelets were recombined and the effects of two species of caldesmon ('caldesmon77' and 'caldesmon140') on the ATPase activities of both systems were examined and analyzed by the method of analysis of variance. (a) The actomyosin system itself is different between artery and platelets, the difference being determined by myosin (P less than 0.05) and not by actin. (b) Platelet tropomyosin differentiates platelet actin from arterial actin (P less than 0.01), while arterial tropomyosin does not. Neither does tropomyosin differentiate myosin. (c) The effect of caldesmon77 differentiates the origins of myosin (P less than 0.01), actin (P less than 0.05) and tropomyosin (P less than 0.05). The effect of caldesmon140 differentiates the origin of myosin (P less than 0.05) and the actin-myosin 'interaction' (combination) (P less than 0.01), but not the origin of tropomyosin (P greater than 0.1). (1) It is concluded that actomyosin/tropomyosin-caldesmon system is distinguishable between platelets and artery. (2) It is suggested that caldesmon is an actomyosin inhibitor which may interact with myosin, in addition to actin and tropomyosin.

Actins↗

PubMed1989

Addition of a methyl group changes both the catalytic velocity and thermostability of the neutral protease from Bacillus stearothermophilus.

Specific activity was compared between wild-type (WT) neutral protease from Bacillus stearothermophilus and mutant protease (M1; Gly144 replaced by Ala144) with enhanced thermostability. When casein was used as a substrate, M1 showed 1.5-times higher specific activity than that of WT. In contrast, the specific activities of M1 for soluble reduced lysozyme and insulin B chain were lower than those of WT by 17.2 and 13.2%, respectively. After digestion of the insulin A chain by these enzymes, the peptide products were purified and the N-terminal amino acid sequences were determined. WT enzyme cleaved insulin A chain at three sites, whereas no digestion was observed with M1. Using Z-Gly-Leu-NH2 as a substrate, the kinetic parameters were determined. The Km values are nearly equal for both enzymes, whereas the kcat of M1 (240 min-1) was much smaller compared to the WT (830 min-1). The data indicate that the mutation (addition of a methyl group) exerts an effect by changing both the catalytic velocity and thermostability.

Amino Acid Sequence↗

PubMed1989

Stimulation of connective tissue-type mast cell proliferation by crosslinking of cell-bound IgE.

Crosslinking of cell-bound IgE on mouse connective tissue-type mast cells (CTMC) by multivalent antigen or anti-IgE antibody induced clonal growth of CTMC in methylcellulose culture containing IL-3. Continuous presence of antigen, IgE antibody, and IL-3 in culture was required for extensive proliferation of CTMC. Optimal concentrations of antigen and anti-IgE antibody for proliferation of sensitized CTMC approximately corresponded to those for maximal histamine release from the cells, and it was observed that most dividing cells stimulated by antigen had pericellular degranulation halos in culture. Experiments of both single cell culture and serum free culture provided evidence for a direct effect of antigen stimulation on proliferation of CTMC. Neither accessory cells nor some factors in FCS were required for the clonal growth of CTMC in our culture condition. Compound 48/80, a direct stimulator of CTMC, also triggered histamine release from CTMC but failed to support their proliferation. These results suggest that stimulation of CTMC via IgE receptors not only triggers the release of chemical mediators from the cells but induces clonal growth of CTMC in the presence of IL-3. Our data indicate the possibility that antigen stimulation may play another role in the proliferation of CTMC.

Animals↗

PubMed1989

Ultrastructural cytochemistry of aortic microfibrils in the Arctic lamprey, Lampetra japonica.

In the ventral aorta of lamprey, microfibrils are major components of the extracellular matrix. With special reference to these microfibrils, we have cytochemically examined the lamprey ventral aorta, utilizing the tannic acid (pH 7.0)-uranyl acetate (TA-UA) method, elastase en bloc digestion, Thiéry's periodic acid-thiocarbohydrazide-silver proteinate (PA-TCH-SP) method, and ferritin- or horseradish peroxidase-labeled concanavalin A (Con A) methods. The lamprey microfibrils were strongly stained with PA-TCH-SP and both Con A methods, but did not show TA-UA staining nor elastase sensitivity. These cytochemical properties of lamprey microfibrils are identical with those of mammalian elastin-associated microfibrils. On the other hand, in spite of extensive examination, TA-UA positive and elastase-sensitive extracellular components were not found, so that lamprey ventral aorta does not appear to contain elastin. These results indicate that lamprey aortic connective tissue contains microfibrils as elastic components, but deposition of amorphous elastin does not occur.

Actin Cytoskeleton↗

PubMed1989

Differential distribution and ultrastructural staining of oxytalan and elastic fibers in the periodontal ligament of Alligator mississippiensis.

We have investigated ultrastructural cytochemical properties of elastic elements in Alligator periodontal ligaments decalcified with EDTA and stained with 1) the tannic acid-uranyl acetate (TA-UA) method for elastin in combination with elastase digestion; 2) the high iron diamine-thiocarbohydrazide-silver proteinate (HID-TCH-SP) method with prior treatment of specimens with either monopersulphate or cupric-sulphite reagent for the localization of disulphide- and/or sulphydryl-containing material (i.e., oxytalan fibers); and 3) HID-TCH-SP alone for sulphated complex carbohydrates. Many microfibrils accumulated to form either large or small bundles. Large bundles having a diameter of 2.50 +/- 1.10 microns (mean +/- SD; n = 50) each showed an apico-occlusal distribution, although small bundles measuring 0.63 +/- 0.13 microns (mean +/- SD; n = 50) in diameter each were exclusively localized in interstitial areas rich in vessels and nerves. The former bundles always lacked TA-UA reactivity and represented oxytalan fibers; the latter bundles frequently contained TA-UA-reactive elastase digestible components and were similar in appearance to immature elastic fibers or elaunin fibers. HID-TCH-SP after oxidation strongly stained both the oxytalan and elastic fiber microfibrils but stained the amorphous elastin very weakly or not all. In nonoxidized specimens, there was no definite HID-TCH-SP staining of microfibrils and the amorphous elastin, although adjacent matrix proteoglycans stained consistently. These results indicate that although there is a marked difference in the distribution and size of oxytalan and elastic fibers in Alligator periodontal ligaments, their associated microfibrils lack stainable sulphate groups but are enriched with disulphide and/or sulphydryl groups, as has been described in mammals.

Alligators and Crocodiles↗

PubMed1989

Cross-reactivity of an antineurofilament antibody with a troponin-T isoform.

Histochemical examination has revealed that a monoclonal antibody raised against the 200-kilodalton (kd) subunit of neurofilament reacts not only with neural tissue but with type 1 and type 2C fibers of skeletal muscle. To identify the cross-reactive substance(s), rat soleus muscle, which includes type 1 and type 2C fibers, was separated into a soluble fraction and an insoluble myofibrillar fraction. Western blot analysis demonstrated that the antibody reacted with 30-kd and 36-kd polypeptides in the soluble fraction and with a 38-kd polypeptide in the insoluble fraction. We isolated a fraction that contained the 38-kd polypeptide from the insoluble fraction. The material in this fraction bound to F-actin. Two-dimensional electrophoresis of the fraction showed that the 38-kd polypeptide was part of the group of isoforms of troponin-T, which was identified by a monoclonal antibody developed against troponin-T. Thus, we conclude that this antineurofilament antibody recognizes one of the isoforms of troponin-T in type 1 and type 2C fibers.

Animals↗

PubMed1989

An improved host-vector system for Candida maltosa using a gene isolated from its genome that complements the his5 mutation of Saccharomyces cerevisiae.

The host-vector system of an n-alkane-assimilating-yeast, Candida maltosa, which we previously constructed using an autonomously replicating sequence (ARS) region isolated from the genome of this yeast, utilizes C. maltosa J288 (leu2-) as a host. As this host had a serious growth defect on n-alkane, we developed an improved host-vector system using C. maltosa CH1 (his-) as host. The vectors were constructed with the Candida ARS region and a DNA fragment isolated from the genome of C. maltosa. Since this DNA fragment could complement histidine auxotrophy of both C. maltosa CH1 and S. cerevisiae (his5-), we termed the gene contained in this DNA fragment C-HIS5. The vectors were characterized in terms of transformation frequency and stability, and the nucleotide sequence of C-HIS5 was determined. The deduced amino acid sequence (389 residues) shared 51% homology with that of HIS5 of S. cerevisiae (384 residues; Nishiwaki et al. 1987).

Base Sequence↗

PubMed1989

Resection of carcinoma in the cervical esophagus following prior removal of a thoracic esophageal carcinoma--a case report.

We report herein, a rare case of a patient who, having undergone resection of a thoracic esophageal cancer, underwent removal of a cervical esophageal cancer, for which a free jejunal graft with microvascular anastomoses was utilized. The tumor in the cervical esophagus had originated from a second primary squamous cell cancer, which had occurred synchronously but had unfortunately escaped detection before the first operation. Due to the high incidence of other multicentric neoplasma or metastatic skip lesions accompanying esophageal carcinoma, careful evaluation during preoperative examinations in order to avoid overlooking another lesion, especially in the cervical portion of the esophagus is imperative.

Carcinoma, Squamous Cell↗

PubMed1989

Magnesium ion: a possible physiological regulator of aldosterone production.

We examined the direct effect of magnesium ion on aldosterone production by adrenal cells using collagenase-dispersed zona-glomerulosa cells in rats. The effects of magnesium on aldosterone production stimulated by angiotensin II or ACTH were also investigated. Both magnesium sulphate (MgSO4) and magnesium chloride (MgCl2) (0 to 2 mM) decreased aldosterone production in a dose-dependent manner. In comparison with magnesium-free medium, 2 mM MgSO4 inhibited aldosterone production by 73% and MgCl2 by 65%. In addition, MgSO4 showed an inhibitory effect on aldosterone production stimulated by angiotensin II (10pM to 10nM), whereas it had no significant effect on aldosterone production due to ACTH stimulation (10pM to 10nM). These data suggest that magnesium has an inhibitory action on aldosterone production in vitro and may be a physiological regulator of aldosterone production.

Adrenocorticotropic Hormone↗

PubMed1989

Cloning and sequencing of two tandem genes involved in degradation of 2,3-dihydroxybiphenyl to benzoic acid in the polychlorinated biphenyl-degrading soil bacterium Pseudomonas sp. strain KKS102.

Two genes involved in the degradation of biphenyl were isolated from a gene library of a polychlorinated biphenyl-degrading soil bacterium, Pseudomonas sp. strain KKS102, by using a broad-host-range cosmid vector, pKS13. When a 3.2-kilobase (kb) PstI fragment of a 29-kb cosmid DNA insert was subcloned into pUC18 at the PstI site downstream of the lacZ promoter, Escherichia coli cells carrying this recombinant plasmid expressed 2,3-dihydroxybiphenyl dioxygenase activity. Nucleotide sequencing of the 3.2-kb PstI fragment revealed that there were two open reading frames (ORFI [882 base pairs] and ORFII [834 base pairs], in this gene order). Results of analysis of Tn5 insertion mutants and unidirectional deletion mutants suggested that the ORFI coded for 2,3-dihydroxybiphenyl dioxygenase. When the sequence of ORFI was compared with that of bphC of Pseudomonas pseudoalcaligenes KF707 (K. Furukawa, N. Arima, and T. Miyazaki, J. Bacteriol. 169:427-429, 1987), the homology was 68%, with both strains having the same Shine-Dalgarno sequence. The result of gas chromatography-mass spectrometry analysis of the metabolic product suggested that the ORFII had meta cleavage compound hydrolase activity to produce benzoic acid. DNA sequencing suggested that these two genes were contained in one operon.

Amino Acid Sequence↗

PubMed1989

Cloning and sequencing of the gene encoding the 72-kilodalton dehydrogenase subunit of alcohol dehydrogenase from Acetobacter aceti.

A genomic library of Acetobacter aceti DNA was constructed by using a broad-host-range cosmid vector. Complementation of a spontaneous alcohol dehydrogenase-deficient mutant resulted in the isolation of a plasmid designated pAA701. Subcloning and deletion analysis of pAA701 limited the region that complemented the deficiency in alcohol dehydrogenase activity of the mutant. The nucleotide sequence of this region was determined and showed that this region contained the full structural gene for the 72-kilodalton dehydrogenase subunit of the alcohol dehydrogenase enzyme complex. The predicted amino acid sequence of the gene showed homology with sequences of methanol dehydrogenase structural genes of Paracoccus denitrificans and Methylobacterium organophilum.

Acetobacter↗

PubMed1989

Inhibitory effect of endothelin on renin release in vitro.

We previously reported that endothelin inhibits renin release in a dynamic superfusion system of collagenase-dispersed rat renal cortical cells. In the present report we investigated cellular mechanisms by which endothelin inhibits renin release from juxtaglomerular (JG) cells. In a superfusion system of dispersed rat renal cortical cells, 10(-10) M endothelin inhibited renin release stimulated by 5 x 10(-8) M isoproterenol or 5 x 10(-5) M 8-(N,N-diethylamino)octyl-3,4,5-trimethoxybenzoate (TMB-8, a putative intracellular Ca antagonist). Endothelin showed a slight but significant inhibitory effect on renin release stimulated by isoproterenol or TMB-8 even in the absence of extracellular Ca. Endothelin also inhibited renin release in the presence of 10(-4) M nicardipine. In a superfusion system of renal cortical slices, both 10(-8) M endothelin and a high concentration (60 mM) of K inhibited renin release, and 10(-6) M nicardipine attenuated the inhibition of renin release by high K but did not affect the inhibition by endothelin. These results suggest that endothelin inhibits renin release from JG cells not only by the promotion of Ca influx into the cells through dihydropyridine-insensitive Ca channels but also by other mechanism(s) independent of extracellular Ca.

Animals↗

PubMed1989

Recanalization of intracranial carotid occlusion detected by duplex carotid sonography.

We studied three patients with internal carotid artery occlusion at the siphon who had recanalization during 1 month of close observation. Angiography and duplex carotid sonography (DCS) were repeated serially in each patient. Blood flow patterns detected by DCS were classified into three patterns by specific angiographic changes. The distal occlusive flow pattern on DCS corresponds to internal carotid artery occlusion at the siphon angiographically, the median flow pattern on DCS corresponds to partial recanalization, and a normal flow pattern on DCS indicates almost complete recanalization. Since DCS can be easily repeated, the exact time of recanalization can be determined noninvasively. In all three patients, hemorrhagic infarction observed on computed tomograms occurred at the time of recanalization detected by DCS. DCS demonstrates that recanalization is one of the mechanisms of hemorrhagic infarction.

Aged↗

PubMed1989

Ultrastructural demonstration of increased sulfated proteoglycans and calcium associated with chondrocyte cytoplasmic processes and matrix vesicles in rat growth plate cartilage.

A monoclonal antibody (3-B-3) to chondroitin 6-sulfated proteoglycan was used with immunoperoxidase electron microscopy to study the relationship of chondrocyte cytoplasmic processes and matrix vesicles in rat epiphyseal growth plate cartilage. Immunoperoxidase staining of the chondrocyte plasmalemma was found at all levels in the growth plate and was most prominent in the hypertrophic zone. The plasmalemma and matrix of the cytoplasmic process often demonstrated stronger reactivity than the remainder of the cell surface. Matrix vesicles showed weak to strong surface or internal reactivity. The majority of them stained very similarly to the cytoplasmic process. X-ray microanalysis of specimens processed by rapid freezing and freeze substitution confirmed that both sulfur and calcium were localized within or in close association with both the cytoplasmic process and the matrix vesicle, suggesting a chemical combination of calcium with sulfated proteoglycans at both sites. These results indicate that there is a selective increase in the concentration of membrane-associated sulfated proteoglycan and calcium in the cell process, from which matrix vesicles may be released into the extracellular matrix.

Animals↗