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T Takeda

Publications and source records attributed to T Takeda.

At least 919 records · Page 51Linked to original sources
PubMed1989

Evidence for a second isoform of the catalytic subunit of calmodulin-dependent protein phosphatase (calcineurin A).

We have used a previously characterized rat cDNA clone for the catalytic (A) subunit of calmodulin-dependent protein phosphatase (calcineurin), which we designated A alpha, to isolate cDNA clones coding for a second isoform of the A subunit, A beta. The A beta cDNA encodes a protein of 525 amino acids that is 81% identical with A alpha. The N-terminal region is dissimilar and contains a characteristic proline-rich sequence. The region homologous to protein phosphatases 1 and 2A (region between residues 87 and 338, 91% identical) and the calmodulin binding domain (region between residues 401 and 424, 96% identical) are highly conserved. The presence of two genes coding for calcineurin A suggests the possibility of important functional differences in the two enzymes.

Amino Acid Sequence↗
PubMed1989

Structural organization of the gene encoding apolipoprotein A-II in an amyloidotic strain of senescence-accelerated mouse.

An inherited polymorphism occurring in the murine apolipoprotein A-II (ApoA-II) transcript seems to be related to the senile amyloidosis which occurs in accelerated-senescence-prone mice (SAM-P). Such being the case, we have determined the entire nucleotide (nt) sequence of the apoA-II gene. The length of the gene is about 1.3 kb and it is interrupted by three introns and the four exons aligned perfectly with the previously sequenced elements of an apoA-II cDNA. Two-nt substitutions [Pro-5(CCA)----Gln(CAG)] in the SAM-P genome were identified in the third exon, hence, we could use a restriction fragment length polymorphism to detect the apoA-II molecular type. Several possible regulatory signals were identified (i) in the 5'-flanking region, including CAAT and TATA boxes, the viral enhancer-like sequence, and the consensus sequences of estrogen response element, and (ii) in the 3'-flanking region, including sequences conserved in the immunoglobulin enhancer, glucocorticoid and estrogen response elements, and a B1 repetitive sequence.

Amino Acid Sequence↗
PubMed1989

Bioluminescent assay for serum adenosine deaminase with immobilized bacterial luciferase.

We describe a bioluminescence method for measuring adenosine deaminase activity in serum. The method involves use of batchwise enzyme reaction containing adenosine, alpha-ketoglutarate, glutamic dehydrogenase and NADH. The resulting solution is injected to the continuous-flow bioluminescence system. In the system, a bacterial luciferase and NAD(P)H:FMN oxidoreductase are covalently co-immobilized on Sepharose 4B. Carrier solution (pH 6.8) for bioluminescence reaction contains FMN and decanal. The continuous-flow light-emitting system, in which the reactor (flow cell packed with immobilized enzyme) is placed in front of a photomultiplier tube inside a photon counter, is versatile and simple. Concentration and response are linearly related from 1.2 to 92.5 pmol per injection of ammonia. The precision of the method is satisfactory (coefficient of variation 3.9-6.8%). We validated the technique by comparing results with conventional assay method (UV method). Normal values for adenosine deaminase activity of serum ranged from 7.0 to 22.0 U/l in agreement with those obtained by other method. The Sepharose 4B-immobilized enzymes are stable for more than one year. This assay system could be used as a routine clinical laboratory test in the diagnosis of liver damage.

Adenosine↗
PubMed1989

The complete primary structure of calcineurin A, a calmodulin binding protein homologous with protein phosphatases 1 and 2A.

A complementary DNA (cDNA) clone encoding the catalytic subunit of calcineurin (calcineurin A) has been isolated from a rat brain cDNA library. The primary structure of the cDNA consists of 2,337 nucleotides including the entire coding region for 521 amino acids, and the calculated molecular mass is 58,643 Da. The calcineurin A is strikingly homologous to protein phosphatases 1 and 2A, approximately 50% of the amino acids over an internal 250-residue region between residues 78 and 329 being identical. Twenty four amino acid-residue region between residues 391 and 414 shows the consensus structural features for a calmodulin-binding domain. These data suggest that the allosteric character of this chimeric enzyme is generated by gene fusion of two separate protein families.

Amino Acid Sequence↗
PubMed1989

Behavioral characteristics of the SAM-P/8 strain in Sidman active avoidance task.

The behavior of the senescence-accelerated mouse (SAM-P/8) at the age of 1, 2, 4 and 10-11 months in Sidman active avoidance learning was analyzed, and compared to findings in the controls (SAM-R/1). At the age of 1 and 2 months, learning was comparable in these two strains. At the age of 4 and 10-11 months, SAM-P/8 but not SAM-R/1 learned active avoidance. We propose that SAM-P/8 can serve as a valid model of deficits in learning and memory.

Aging↗
PubMed1989

Activation of type I cyclic AMP-dependent protein kinases is impaired by a point mutation in cyclic AMP binding sites.

The type I regulatory (R-I) subunit of cyclic AMP-dependent protein kinase (A-kinase) was expressed in E. coli, and a single amino acid substitution in cyclic AMP binding sites A or B was introduced by site-directed mutagenesis. The cyclic AMP binding activity and cyclic AMP-stimulated phosphotransferase activity of the holoenzymes formed by wild-type or mutant R-Is and the purified bovine catalytic subunit of A-kinase were then examined. The wild-type holoenzyme was activated by low concentrations of cyclic AMP, a finding in accord with its high-affinity binding to cyclic AMP. In contrast, although the two mutant holoenzymes showed high-affinity cyclic AMP binding at their non-mutated sites, both holoenzymes were resistant to activation by cyclic AMP. Thus, binding of cyclic AMP to the non-mutated cyclic AMP binding site is not sufficient to dissociate the catalytic subunit from the mutant R-Is upon cyclic AMP binding. These results suggest that both A and B cyclic AMP binding sites are required for efficient coupling between cyclic AMP binding and activation of the enzyme.

8-Bromo Cyclic Adenosine Monophosphate↗
PubMed1989

Mastoparan, a wasp venom, stimulates insulin release by pancreatic islets through pertussis toxin sensitive GTP-binding protein.

A wasp venom, mastoparan, rapidly stimulated insulin release by rat pancreatic islets in a dose-related manner. The amount of insulin released in response to 58 microM mastoparan far exceeded that induced by 27.8 mM glucose. Mastoparan stimulated insulin release to similar degrees at ambient glucose concentrations of 1.7 mM and 5.6 mM. The islets obtained from pertussis toxin-treated rats showed unequivocally less response to mastoparan. Pretreatment of islets with bromophenacyl bromide, a phospholipase A2 inhibitor, abolished their responsiveness to mastoparan. Pretreatment of islets with nifedipine, a Ca2+ channel blocker, was without effect. Mastoparan is a unique stimulator of insulin release by the pancreatic islets, which acts through GTP-binding protein(s) and phospholipase A2.

Acetophenones↗
PubMed1989

The clinical significance of iC3b neoantigen expression in plasma from patients with systemic lupus erythematosus.

We studied the expression of an iC3b neoantigen (iC3b-NEO) in plasma from patients with systemic lupus erythematosus (SLE), by using a monoclonal antibody specific for iC3b/C3dg/C3d, to investigate the activation of the third component of complement in SLE. The plasma iC3b-NEO level in 40 untreated patients with active SLE was significantly higher than that in 36 normal subjects (mean +/- SD 31.5 +/- 13.9 micrograms/ml versus 12.3 +/- 3.3 micrograms/ml; P less than 0.001). The plasma iC3b-NEO level was highly correlated with clinical disease activity (tau = 0.62, P less than 0.0001), and it was the parameter most closely correlated with renal histologic activity in lupus nephritis (tau = 0.52, P less than 0.0001). Also, patients with diffuse proliferative lupus nephritis had the highest levels of plasma iC3b-NEO among all World Health Organization classes of lupus nephritis (P less than 0.01). We conclude that the plasma iC3b-NEO level is strongly associated with clinical disease activity and renal histologic activity in patients with SLE, and that plasma iC3b-NEO may be a sensitive and useful measure of complement activation in SLE.

Antibodies, Monoclonal↗
PubMed1989

Relationship of the effects of interferon on chronic hepatitis B and the induction of 2',5'-oligoadenylate synthetase.

Two years or more after 35 patients (29 men and six women) with chronic hepatitis B were treated by interferon, we studied relationships of age, ALT activity, activity of serum DNA polymerase associated with the hepatitis B virus, serum levels of hepatitis B e antigen and activity of 2',5'-oligoadenylate synthetase in peripheral blood mononuclear cells when treatment started in comparison with treatment results. Seventeen patients were given human lymphoblastoid interferon-alpha; the other 18 patients were given interferon-beta. We measured the activity of 2',5'-oligoadenylate synthetase in these mononuclear cells and found the rate of increase in vivo and in vitro; the correlation between the two was r = 0.68. This enzyme activity in the patients who became negative for DNA polymerase after interferon treatment increased more both in vivo and in vitro than in patients who did not became negative. Also, both the in vivo and in vitro activity increased more in patients who became negative for the e antigen after interferon therapy than in those who remained positive. In the first group, interferon was considered to be effective; in the second, ineffective. Of the patients who became negative, some developed e antibodies and some did not; the increase in this enzyme activity in the two groups was not significantly different. The increase in the activity of 2',5'-oligoadenylate synthetase activity could be used to predict the results of interferon treatment and is an index that can be used before treatment to predict the response.

2',5'-Oligoadenylate Synthetase↗
PubMed1989

Detection of the ras p21 gene product in human leukemias by flow cytometry.

To date, the detection of oncogene products in human neoplasms has relied primarily upon immunoblot analysis of specimen homogenates. Herein are reported the results of a study using flow cytometry to evaluate the expression of the ras p21 gene product in both fresh and cryopreserved specimens of human acute leukemias. Cell lines known to express ras p21 were used as positive controls and normal peripheral blood was used as a negative control. Intensity of staining for ras p21 (Ip21) was expressed as the ratio of the peak channel numbers of the peak generated by staining with anti-ras p21 to the peak obtained by staining with an isotype control. Using this method, 21 out of 32 clinical specimens of acute leukemia were found to express ras p21 in elevated amounts compared to normal peripheral blood. Flow cytometry appears to be a practical method for routine screening of clinical specimens for the expression of oncogene products on individual cells rather than cell homogenates.

Flow Cytometry↗
PubMed1989

Japanese experience of screening.

In Sapporo City, the mass-screening for neuroblastoma concerning the urine of infants at about 6 months of age, started in 1981. After 1984, the quantitative determination of VMA, HVA in the urine was carried out using high performance liquid chromatography from the first step. About 104,000 babies have received the screening during the last 7 years, and 19 patients were found (incidence of detection 1:5,500). Except for one, who died of the duodenal perforation shortly after the surgery, all other patients are surviving free from disease. Among 10,000 neonates, we determined urinary concentration of VMA, HVA, and no positive cases were found. However, from this group, 2 patients we detected by the mass-screening at 6 months of age (1:5,000). After the start of mass-screening, the number of the patients with this tumor in much earlier stages and younger ages increased, clarifying that the main cause for improvement of the survival rates of neuroblastoma in Sapporo.

Chromatography, High Pressure Liquid↗
PubMed1989

Olivary branching projections to the flocculus, nodulus and uvula in the rabbit. II. Retrograde double labeling study with fluorescent dyes.

The previous electrophysiological study reported that some of the Purkinje cells in the vestibulocerebellum were innervated by branching climbing fibers. To identify the cells of origin of these branching climbing fibers, a pair of retrograde fluorescent tracers, propidium iodide in combination with 4', 6-diamidino-2-phenylindole or diamidino yellow, were injected into two sites in the flocculus, nodulus and uvula. Proportions of double labeled neurons out of all labeled neurons in each subdivision of the contralateral inferior olive were studied. In cases of injections into the flocculus and nodulus, 13% (maximum 27%) of all the labeled neurons in the dorsal cap and 6% (maximum 12%) in the ventrolateral outgrowth were double labeled. In cases of injections into the nodulus and uvula, 20% neurons (maximum 34%) of the labeled neurons in the dorsal cap and 8% of those in the nucleus beta were double labeled. The present retrograde labeling study revealed that some dorsal cap neurons project to the uvula, which has not been reported previously in the rabbit. Injections into the flocculus and uvula caused only slight double labeling (0.4%) in the inferior olive.

Amidines↗
PubMed1989

Olivary branching projections to the flocculus, nodulus and uvula in the rabbit. I. An electrophysiological study.

Olivocerebellar branching projections to the flocculus, nodulus and uvula were studied electrophysiologically in pigmented rabbits anesthetized with pentobarbital and halothane. Neurons in the dorsal cap of the inferior olive were antidromically activated by stimulation of the contralateral flocculus, nodulus and uvula. The antidromic responses in the dorsal cap from the flocculus, nodulus and uvula partially occluded with each other. Electrical stimulation of the nodulus (or uvula) evoked early and late climbing fiber responses in the flocculus with latencies of 4.0 ms and 10.0 ms, respectively. The early response was resistant to repetitive stimulation and not affected by interruption of the olivocerebellar fibers at the lower medulla, while the late response was abolished by these two procedures. This indicated that the early response was evoked through climbing fiber branches to the flocculus and nodulus (or uvula) as an axon reflex, while the late response was evoked via the inferior olive. Of 76 Purkinje cells in the flocculus, 35.6% showed climbing fiber activation through branches to the nodulus and/or uvula, 70% of which were orthodromically activated through climbing fibers from the contralateral optic tract. Electrical stimulation of the flocculus or uvula evoked the early and late climbing fiber responses in the nodulus. Of 60 Purkinje cells in the nodulus, 63.4% showed axon reflex activation from the flocculus and/or uvula, 42% of which were activated through climbing fibers from the contralateral optic tract. These findings demonstrated that the flocculus, nodulus and uvula receive branching climbing fiber projection from the inferior olive, a part of which conveys visual information.

Action Potentials↗
PubMed1989

Plasminogen activation in plasma of patients with systemic lupus erythematosus.

We measured alpha 2-plasmin inhibitor-plasmin complexes (PI-PC) in plasma of patients with systemic lupus erythematosus (SLE) to examine the plasminogen activation in SLE. The plasma PI-PC level in 23 patients with SLE was significantly higher than that in 18 normal subjects (P less than 0.001) and the SLE patients with nephrotic syndrome had higher plasma PI-PC levels than those without nephrotic syndrome (P less than 0.01). In addition, the plasma PI-PC level was significantly correlated with the level of plasma C3 breakdown products (iC3b/C3dg) in the patients with SLE (r = 0.53, P less than 0.01). These results suggest that plasminogen is activated in plasma of patients with SLE and that the plasminogen activation may be associated with the activation of complement in SLE.

Adult↗
PubMed1989

Long-term follow-up study of children with chronic ITP.

A total of 126 children with chronic idiopathic thrombocytopenic purpura, including 35 splenectomized cases, were investigated in a long-term follow-up study, with regard to residual hematologic and immunologic abnormalities, complications and physical growth. Such hemorrhagic symptoms as petechiae, ecchymosis and epistaxis were still observed in about 22%-28% of the patients with a period of morbidity ranging from 3 to 15 years after onset. Residual thrombocytopenia below 150,000/microliters was found in 62% of patients within 5 years, 59% within 5 to 9 years and 57% within 10-14 years after onset. Other abnormalities were mild anemia, low serum level of IgA or IgM, positive antinuclear antibody, rheumatoid factor, and positive Coombs test in a small number of patients. Increased platelet-associated IgG was still obtained in patients with subnormal platelet counts whose morbid periods were 6 to 27 years after onset. Investigation of the patients by questionnaire revealed such complications as obesity, striae atrophicae, abdominal pain, headache, cataract, Perthes' disease, and cardiac complication in some patients. No apparent disturbances except for obesity were observed in their physical growth.

Autoimmune Diseases↗
PubMed1989

Intense accumulation of indium-111 leukocytes in peritonitis carcinomatosa.

In order to detect the infectious foci in a case of terminal recurrent cancer of the sigmoid colon with intense inflammation, In-111 oxine leukocyte scintigraphy was performed. Leukocytes labeled with In-111 oxine quickly localized within the region of peritonitis carcinomatosa and could be imaged after 4 hours. With time, high activity appeared in this area. And 48 hours after injection, the large intestine was clearly seen. However, no activity was seen in the main recurrent tumor. This suggested that the labeled leukocytes had accumulated in regions of inflammation rather than in malignant tissue. When performing In-111 leukocyte scintigraphy for diseases in which tumor cells and inflammation are mixed, distinguishing the two components is particularly important, and time-sequential scanning is very useful.

Adenocarcinoma, Papillary↗
PubMed1989

Ga-67 scintigraphy in chromomycosis.

We examined an interesting case of chromomycosis that had a characteristic Ga-67 accumulation. This patient had had widespread chromomycosis skin lesions for 8 years. We performed Ga-67 scintigraphy in an attempt to obtain additional information on the site and extent of the lesion. Ga-67 scintigraphy revealed not only all subcutaneous nodules but also an unsuspected enlarged lymphnode and a visceral lesion. This case indicates that Ga-67 scintigraphy is a very useful method to use in detecting the site and extension of chromomycosis, especially in the nodal and the visceral lesions, and sometimes might help in differential diagnosis.

Chromoblastomycosis↗