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T Hachiya

Publications and source records attributed to T Hachiya.

At least 19 recordsLinked to original sources
PubMed1992

Purification and characterization of a low M(r) GTP-binding protein, c25KG, from human platelet membranes.

A low M(r) GTP-binding protein with a M(r) of 26,000 has been purified from a sodium cholate extract of human platelet membranes by using an antibody raised against a synthetic peptide of c25KG, which was previously purified from human platelet cytosol (Nagata, N., et al. (1989) J. Biol. Chem. 264, 17000-17005). The M(r) of membranous c25KG (m-c25KG) was slightly higher than that from cytosolic c25KG (M(r) 25,000) and calculated to be 26,000. It was suggested that m-c25KG contains an equimolar amount of GDP. The purified protein could bind approx. 1 mol of [35S]guanosine 5'-O-(thiotriphosphate)(GTP gamma S)/mol of protein, with a Kd value of 50 nM. [35S]GTP gamma S-binding to this protein was inhibited by GTP and GDP, but not by ATP and ADP, showing that the binding is specific for guanine. In the presence of 10 mM Mg2+, the dissociation of [8,5'-3H]GDP from the m-c25KG occurred with a rate of 0.01 min-1. The rate of release of Pi from [gamma-32P]GTP-bound m-c25KG was calculated to be 0.03 min-1. These results indicate that c25KG is also present in membrane fraction of human platelet which has very similar biochemical properties in those of the cytosolic type.

Antibody Specificity↗
PubMed1992

Plasminogen activators and plasminogen activator inhibitor 1 before and after venous occlusion of the upper limb in thromboangiitis obliterans (Buerger's disease).

Plasma levels of plasminogen activators (t-PA, u-PA) and their inhibitor (PAI-1) were studied in patients suffering from Buerger's disease and healthy volunteers before and after 15 minutes of venous occlusion test. The baseline levels of t-PA in group of patients did not differ from those of controls. On the contrary patients with Burger's disease showed a marked increase in u-PA antigen concentrations with concomitant decrease in PAI-1 antigen levels. During venous stasis t-PA antigen concentrations increased in all subjects, however it was much pronounced in controls. Venous occlusion resulted in significant decrease in free PAI-1 levels in the group of patients only. In conclusion, Buerger's disease is associated with the endothelial derangement with increased u-PA release and decreased PAI-1 release, which does not influence the function of fibrinolytic system. The fact that the reduced response of the endothelium to release t-PA after venous stasis goes in parallel with marked decrease in PAI-1 antigen levels seems to suggest that patients suffering from Buerger's disease are not at high risk of intravascular fibrin deposition.

Arm↗
PubMed1992

Acute aortic thrombosis associated with spinal cord infarction in nephrotic syndrome.

Acute aortic thrombosis associated with spinal cord infarction in a 47-year-old man with nephrotic syndrome is described. He was admitted to our hospital presenting with the nephrotic syndrome. Renal biopsy revealed mild mesangial proliferative glomerulonephritis. The urinary protein excretion rate transiently decreased after the start of treatment with prednisolone, but it increased again and was followed by the development of the signs and symptoms of spinal cord infarction, which was diagnosed by magnetic resonance signal abnormalities, and then symptoms of ischemia in the lower limbs. Digital subtraction angiography revealed an obstruction at the bifurcation of the abdominal aorta. Emergency thrombectomy was performed, and the arterial blood flow was reestablished. Laboratory data on the fibrinocoagulation system showed a hypercoagulable state. In this case, fibrinocoagulation abnormalities due to the nephrotic syndrome led to the hypercoagulable state, and dehydration might have triggered the thrombotic complication.

Acute Disease↗
PubMed1992

[Principle of treatment of intermittent claudication due to arteriosclerosis obliterans--reconstruction or conservative treatment].

MATERIALS AND METHODS: Two hundred and one patients of arteriosclerosis obliterans (ASO) with intermittent claudication (IC) were studied. Improvement of IC, score of return to social life, change of life condition and prognosis were compared between the two groups of reconstructive and conservative treatment. RESULTS: Improvement of IC was seen in 88.0% of the patients in the group of reconstruction and only 30.4% in the conservative treatment group. In the reconstructive group, the score of return to social life improved from 2.10 to 1.31 and the score of life condition also improved from 2.71 to 1.66. However in the conservative treatment group these score showed no significant improvement. Moreover the long term mortality rate was lower in the treatment group of reconstruction. CONCLUSION: The arterial reconstruction for IC is significant for improving the quality of life and exerts a favorable effect on life prognosis.

Aged↗
PubMed1992

Antitumor activity of recombinant human tumor necrosis factor in combination with hyperthermia against heterotransplanted human prostatic carcinoma and its lymph node metastasis in nude mice.

The antitumor activity of recombinant human tumor necrosis factor (rhTNF) against heterotransplanted human prostatic carcinoma (PC-3) and spontaneous lymphatic tumor metastasis was studied in vivo. The spontaneous lymphatic metastasis of PC-3 tumor was found in approximately 50% of cases. Significant antitumor activity was observed with repeated intratumoral administration of a large dose of rhTNF, not only on the subcutaneous tumor xenografts but also on the lymph node metastases. Strong antitumor activity could be achieved even with the intratumoral administration of a small dose of rhTNF in combination with mild hyperthermia on either the transplanted tumors or on the metastatic tumors.

Acid Phosphatase↗
PubMed1991

Bleeding peptic ulcer after abdominal aortic aneurysm surgery.

A retrospective study of 112 patients with abdominal aortic aneurysm (AAA) and 232 with arteriosclerosis obliterans (ASO) demonstrated that 16.7% of those with AAA and 1.6% of those with ASO had a history of gastroduodenal ulcer; 83% of these lesions with AAA were gastric ulcers. Ulcer bleeding after vascular reconstruction developed in seven patients with AAA and one with ASO. Serum fibrinogen levels and platelet counts were significantly lower in patients with AAA than in those with ASO or controls. A prospective study showed that 25 (52.1%) of 48 patients with AAA and six (20.0%) of 30 patients with ASO had endoscopically proved gastroduodenal lesions before vascular reconstruction. None of them developed postoperative bleeding after treatment of both their gastroduodenal lesions and coagulopathy. Furthermore, the significant decrease in blood flow and prostaglandin content of gastric mucosa was demonstrated in patients with AAA.

Aged↗
PubMed1991

Identification and characterization of protein kinase C-related enzymes in frog retina.

We isolated two types of protein kinase C-related enzymes (fPKC) in frog (Rana catesbeiana) retina. Three sequential steps of column chromatography of DEAE-cellulose, butyl-Toyopearl, and hydroxylapatite were carried out and resulted in the separation of two types of distinct Ca2+/phospholipid-dependent protein kinase activities. These proteins reacted with antibodies raised against synthetic peptides based on the predicted amino acid sequences of rat protein kinase C delta or zeta subspecies, and showed molecular masses of 90 and 75 kDa on sodium dodecyl sulfate-polyacrylamide gel electrophoresis, respectively. Immunocytochemical analysis of 90 and 75K fPKC in frog retina revealed that the 75K fPKC was localized in the outer segment of cone cells and in the microvillar projections of Müller cells. These results suggested that fPKCs play differential roles on the photosignal transduction in frog retina.

Amino Acid Sequence↗
PubMed1991

Different binding of stimulatory-type and blocking-type TSH receptor antibody with guinea-pig testis membrane.

A receptor assay using [125I]bTSH-binding to guinea-pig testis membrane was developed. Unlabelled hCG and FSH inhibited [125I]bTSH binding. In patients with Graves' disease and in untreated hyperthyroid patients, almost all long-acting thyroid stimulators and thyroid-stimulating antibodies, respectively did not inhibit [125I]bTSH binding, which on the other hand was inhibited by thyroid stimulation blocking antibodies in patients with primary hypothyroidism. When the inhibitory effect on the binding of [125I]hCG and 125I-synthetic alpha-subunit peptide (alpha 26-46) of hCG to testis membrane was examined, bTSH resulted in a significant inhibition. However, all three kinds of TSH receptor antibodies had no inhibitory effect. This study demonstrated 1. interaction of alpha-subunit of TSH and hCG with the testicular receptor; 2. binding of thyroid stimulation-blocking antibody and lack of binding of thyroid-stimulating antibody to the testicular TSH receptor in spite of binding of these TSH receptor antibodies to the thyroidal TSH receptor, and 3. lack of binding of thyroid-stimulating antibody and thyroid stimulation-blocking antibody to the testicular gonadotropin receptor.

Amino Acid Sequence↗
PubMed1991

[Occlusion of the right pulmonary artery due to acute dissecting aortic aneurysm].

A 58-year-old female was admitted with an abrupt onset of chest and back pain. The CT scan of the chest showed aortic dissection of the ascending aorta and proximal aortic arch, but the false lumen of the aortic dissection had already been occluded by a blood clot. After admission, she complained of chest pain with hemoptysis and presented facial edema and the distention of the neck veins. The pulmonary angiogram showed complete occlusion of the right pulmonary artery at the proximal segment. These findings were interpreted as pulmonary embolism. She was treated with intravenous heparin and urokinase, but these treatments did not demonstrate any improvement. She underwent a surgical exploration on the fourth hospital day. During surgery, the right pulmonary artery was discovered to be compressed and occluded by the large dissecting aneurysm of the ascending aorta. In addition, hematoma was seen between the right pulmonary artery. The ascending aorta and pulmonary trunk, which was injured in the operative procedure, were replaced with an artificial graft successfully. Postoperative pulmonary angiogram showed no stenosis of right pulmonary artery. The occlusion of the pulmonary artery by an acute dissecting aneurysm is an extremely rare complication and it is often wrongly diagnosed as pulmonary embolism. In such cases, the correct diagnosis and prompt surgical treatment is essential and antithrombolytic and anticoagulant therapy should be avoided.

Acute Disease↗
PubMed1990

Assessment of protein kinase C isozymes by enzyme immunoassay and overexpression of type II in thyroid adenocarcinoma.

A two site enzyme immunoassay which quantitatively identifies types I, II, and III of protein kinase C isozymes has been designed. The soluble protein kinase C isozymes were selectively immobilized by type-specific monoclonal antibodies, MC-1a, -2a, and -3a (H. Hidaka et al., J Biol. Chem., 263: 4523-4526, 1988) which bind to the regulatory domain (NH2-terminal side) of protein kinase C. The amount of each isozyme was then determined using a horseradish peroxidase-conjugated polyclonal antibody raised against the COOH-terminal peptide of protein kinase C. By adding increasing concentrations of the antigen, the range of the assay proved to be 0.51-51, 0.081-8.1, and 0.31-31 nM for types I, II, and III, respectively. This sandwich method was used to determine the level of protein kinase C isozymes in rabbit tissues. Type I was mainly present in the cerebrum and cerebellum; the highest amount of type II isozyme was present in blood platelets [26.0 +/- 3.8 (SE) micrograms/g wet tissue]. We compared the protein kinase C isozyme levels in human normal thyroid gland and thyroid cancer tissues and found that type II protein kinase C specifically increased in thyroid cancer tissues. Immunocytochemical examination using MC-2a revealed that the cytoplasm of the cancer cells showed prominent immunoreactivity for type II isozyme.

Adenocarcinoma↗
PubMed1990

Immunoaffinity purification of type I protein kinase C.

We designed a simple procedure for the purification of type I protein kinase C, using immunoaffinity chromatography with a monoclonal antibody, MC-1b, obtained by rescreening hybridoma cells available for an affinity ligand. Western blotting demonstrated that MC-1b specifically reacted with type I protein kinase C, and the enzyme molecule dissociated from MC-1b-coupled Sepharose 4B with mild eluants such as thiocyanate retained the kinase activity. A 1148-fold purification was achieved and 210 micrograms of type I protein kinase C was obtained from three rabbit brains, by means of a two-step procedure, using DEAE-cellulose and immunoaffinity chromatography. The resultant preparation was homogeneous, as indicated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis hydroxylapatite chromatography, and immunological analysis using MC-1a, MC-2a, and MC-3a.

Animals↗
PubMed1990

Type-specific expression of protein kinase C isozymes in CNS tumor cells.

We examined specific expression of protein kinase C (PK-C) isozymes in cultured human glial and neuronal cell lines, using type-specific monoclonal antibodies MC-1a, -2a, and -3a (Hidaka H. et al., J. Biol. Chem., 263 (1988) 4523-4526). Immunoblotting experiments revealed that a 80 kDa band of three kinds of glioblastoma cells (A-172, SK-MG-1, SK-MG-4) was stained with MC-3a, whereas that of neuroblastoma cells (SK-N-MC) reacted with MC-2a. Immunoenzymetric assay showed that glioblastoma cells (A-172, SK-MG-1, SK-MG-4) contained 127.6 +/- 14.4, 248.8 +/- and 148.5 +/- 35.8 ng/mg protein of type III. respectively, while neuroblastoma cells (SK-N-MC) contained 389.5 +/- 20.7 ng/mg protein of type II. These results suggest that PK-C isozymes may be specifically expressed, depending on types of central nervous system (CNS) tumor cells.

Cell Line↗
PubMed1990

Expression of protein kinase C isozyme in epidermal Langerhans cells of the mouse.

Protein kinase C (PKC) is encoded by a complex of a gene family, and its multiple isozymes are expressed in various mammalian tissues. We examined whether PKC is expressed in epidermal Langerhans cells (LC) of the mouse by using monoclonal antibodies specific to PKC I, PKC II, and PKC III isozymes (respective products of PKC genes gamma, beta, and alpha). Immunohistochemical and immunoblotting studies revealed that LC of adult C57BL/6 mice express PKC II, while PKC I and PKC III were not detected. In keratinocytes, none of the isozymes were detected. These results suggest that PKC II is a novel marker of LC and that it possibly plays a regulatory role in epidermal LC of the mouse in vivo.

Animals↗
PubMed1990

Different expression of protein kinase C isozymes in pancreatic islet cells.

To elucidate differential roles of protein kinase C isozymes in pancreatic islet cells, the precise localization of the isozymes in rabbit and rat islet endocrine cells was investigated using monoclonal antibodies specific for three types of the enzyme. We detected strong immunoreactivity for the type III protein kinase C in B cells. Immunoreactivity for the type II enzyme was seen in A cells, and no apparent immunoreactivity for type I was observed in the islet cells. The expression of the type III protein kinase C in B cells was confirmed using rat insulinoma cells. The predominant expression of the type III enzyme in these cells was shown by immunoblotting. Moreover, on the basis of an enzyme-linked sandwich immunoassay, the levels of protein kinase C isozymes were determined in these cells. The significant amounts of the type III enzyme was detected, but the contents of the type I and II enzyme were under detectable level. These results suggest that the type III protein kinase C is involved in the regulation of insulin release in pancreatic B cells.

Adenoma, Islet Cell↗
PubMed1990

Coexistence of autoantibody to human thyrotropin (TSH) and autoanti-idiotypic antibody to antihuman TSH antibody in a case with simple goiter.

A 70-yr-old woman with simple goiter showed normal serum levels of T4, T3, free T4, TSH receptor antibody (TRAb) and increased TBG. Discrepancy in serum hTSH level was observed by different assay methods. Coexistence of both autoantibodies for hTSH and for anti-hTSH antibody were demonstrated by the reaction of the patient's antibody with both 125I-hTSH and 125I-anti-hTSH (monoclonal antibody; mAb). These two autoantibodies belong to the polyclonal immunoglobulin G (IgG). The autoantibody for hTSH recognized only beta-subunit of hTSH. Neither stimulating type of TRAb in Graves' disease nor blocking type of TRAb in primary hypothyroidism interfered with the binding of the patient's antibody to 125I-hTSH or 125I-anti-hTSH. Anti-idiotypic antibody (anti-ID antibody) for anti-hTSH antibody was purified by anti-hTSH antibody affinity chromatography. The binding reaction of 125I-anti-hTSH (mAb) with this anti-ID antibody could be inhibited by the unlabeled hTSH. This anti-ID antibody might represent the internal image of the nonbiological active site of TSH molecule, because of absence of thyroid stimulating activity. Goiter in this patient may have occurred by the unbound TSH with IgG (free TSH) and the bound TSH with IgG, because TSH levels in both the whole serum and the IgG free serum (the unbound TSH with IgG) were decreased significantly by T4 treatment. Coexistence of these antibodies may participate in the autoimmune mechanism of an idiotype-anti-idiotype network.

Aged↗
PubMed1990

The inhibition by calmodulin of thyroid-stimulating hormone binding to epididymal fat, testis and thyroid membranes in the guinea-pig.

Calmodulin inhibited 125I-labelled TSH binding to the membranes of various target tissues for TSH (thyroid, epididymal fat and testis) of the guinea-pig. This inhibition was abolished by adding EGTA (1 mmol/l). Calmodulin did not inhibit the binding of 125I-labelled epidermal growth factor (EGF) to these membranes. It is suggested that the inhibitory effect of calmodulin on the binding of TSH to the receptor is specific and that this mechanism is due to the direct binding of calmodulin to receptor membranes. The ability of calmodulin to bind to the membranes was calcium-sensitive while that of TSH was not. The binding of 125I-labelled calmodulin to these membranes increased significantly when the endogenous calmodulin in the membranes was removed by EGTA. It was not inhibited by a pure preparation of TSH, but it was inhibited by contaminated calmodulin in a crude TSH preparation. On the other hand, 125I-labelled TSH binding to these membranes did not change after the removal of endogenous calmodulin. In conclusion, exogenous calmodulin has an inhibitory effect on the binding of TSH but not of EGF to the membranes of guinea-pig thyroid, epididymal fat and testis.

Animals↗
PubMed1990

Binding of bovine and porcine pituitary glycoprotein hormone alpha-subunit to TSH antibody in serum of patients with Graves' disease.

The characteristics of autoantibodies reactive with bovine (b) TSH were examined in the sera of six patients with Graves' disease selected on the basis of highly negative values in the TSH receptor assay. Test sera were incubated with other 125I-labeled pituitary glycoprotein hormones and their isolated subunits (alpha and beta) [human (h) TSH, bTSH, porcine (p) TSH, pFSH, bFSH, bLH and equine (e) chorionic gonadotropin (CG)] (purity was confirmed by gel-filtration on Sephadex G-100 and SDS-PAGE), and the antibody bound fraction was precipitated by the addition of anti-human gamma-globulin (goat). Almost all sera showed detectable binding to bTSH, pTSH, pFSH, pTSH-alpha, bFSH-alpha, bLH-alpha, but not to hTSH, hTSH-alpha, hTSH-beta, hFSH, hLH, hCG, pTSH-beta, bLH-beta, eCG-alpha. Exceptions were very low binding to bLH-beta by one serum and to pTSH-beta, by two sera. The level of binding (B/T%) of the patients' sera to pTSH-alpha, bFSH-alpha and bLH-alpha was 3.0-27.7%, 2.6-45.3% and 2.2-39.0%, respectively; that of sera from normal healthy adults was 1.9 +/- 0.3%, 0.8 +/- 0.2% and 0.9 +/- 0.2% (mean +/- SD), respectively. These results indicate that the TSH antibodies recognize mainly an epitope in the alpha subunit of bovine and porcine pituitary glycoprotein hormones (TSH, FSH, LH).

Animals↗