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T Takao

Publications and source records attributed to T Takao.

At least 109 records · Page 6Linked to original sources
PubMed1997

[A case of recurrent IgA nephropathy following renal transplantation under tacrolimus (FK506)].

We report a case of recurrent IgA nephropathy following renal transplantation under tacrolimus (FK506). A 23-year-old female who had been diagnosed with IgA nephropathy was transplanted from her HLA two-mismatched mother under tacrolimus, prednisolone and azathioprine. Two years after transplantation, suddenly she noticed macroscopic hematuria. At that time, functional renal deterioration (serum creatinine: 2.3 mg/dl) and mild proteinuria were observed. Allograft biopsy disclosed acute cellular rejection. She was administered a bolus injection of methylprednisolone, 15-deoxyspergualin and anti-lymphocyte globulin. However, the response to the treatment was poor. A transplant biopsy revealed focal segmental glomerulosclerosis by PAS staining and granular IgA and C3 deposits on immunofluorescence examination. There was no sign of acute rejection and toxicity by tacrolimus. We diagnosed recurrent IgA nephropathy. At the present time, she has normal urinalysis and renal function is stable (serum creatinine: 1.9 mg/dl). No proteinuria was observed after total dosage of immunosuppressants was increased. Although recurrence of IgA nephropathy in renal allograft is frequent, allograft dysfunction is rare. However, IgA nephropathy has several types with different prognosis. For functional renal deterioration after renal transplantation, we should consider not only an acute rejection or the toxicity of immunosuppressants but also recurrent nephropathy.

Adult↗
PubMed1997

[The study of continuous infusion chemotherapy with low-dose cisplatin and 5-fluorouracil for patients with primary liver cancer].

Twelve patients with unresectable primary liver cancer (hepatocellular carcinoma and cholangiocarcinoma) and postoperative recurrence of primary liver cancer received continuous arterial or systemic infusion of low-dose CDDP/5-FU. This infusion chemotherapy was continued for five days, discontinued for two days, and repeated four weeks as one course basally. The partial response rate in patients with HCC or CCC treated with intra-arterial infusion was 20% and 33%, respectively. The rate in patients with HCC or CCC treated with systemic infusion was 0% and 33%, respectively. The response rate included decrease of tumor markers in all patients with HCC or CCC was 33% and 67%, respectively. These results suggest that low-dose CDDP/5-FU therapy may be effective in patients with CCC. Severe side effects such as gastro-duodenal ulcer (4 cases) and pseudomembranous colitis (1 case) were observed. The careful management of side effects should be required during this therapy.

Aged↗
PubMed1997

[A case of renal cell carcinoma found after skin metastasis].

A case of renal cell carcinoma, found after skin metastasis is presented. A 76-year-old woman came to our hospital complaining of two painless subcutaneous tumors in her left chest. Histopathological diagnosis was clear cell carcinoma. She underwent left nephrectomy and histopathological findings revealed renal cell carcinoma, alveolar type, clear cell subtype, grade 1. Lung metastasis was proved soon after the operation. We removed skin metastasis several times after the nephrectomy.

Aged↗
PubMed1997

[Current status and problems of home parenteral nutrition for terminal cancer patients from the viewpoint of indication].

Since June 1993, we have been performing home parenteral nutrition (HPN) for end-stage cancer patients. We studied how many patients could be treated with HPN, why they were not able to be treated with HPN in the terminal stage cancer patients, 158 cases, who admitted and died in our ward from June 1993 to April 1997. Eighty-six patients (54.4%) were considered to not be indicated for HPN, due to general weakness (28 cases), dyspnea (17 cases), need for medical care other than HPN (34 cases), and inability to understand this treatment (1 case). Fifty-six patients (35.4%) were considered to have been able to be treated with HPN and could have had returned home. Fifteen patients (26.8%) were given HPN. Four cases wanted to stay in the hospital after they knew the truth and the prognosis of their disease. Another four patients became weak while preparing for HPN and could not go home. Eighty percent of patients could not to be treated with HPN because of the factors of their family. Eight patients had no family to cared for them. Twelve patients were refused to the truth of their disease. The families of 13 cases refused to accept and care for them in their home. We may conclude that co-operation among patients, their family and the medical staff is the most important factor in providing HPN for end-stage cancer patients.

Adult↗
PubMed1996

Molecular identification and characterization of cytosolic isoforms of glutamine synthetase in maize roots.

In maize, a small multigene family encodes the cytosolic isoforms of glutamine synthetase (GS), and five cDNAs, designated pGS1a, pGS1b, pGS1c, pGS1d, and pGS1e, have been cloned (Sakakibara, H., Kawabata, S., Takahashi, H., Hase, T., and Sugiyama, T. (1992) Plant Cell Physiol. 33, 49-58; Li, M., Villemur, R., Hussey, P. J., Silflow, C. D., Gantt, J. S., and Snustad, D. P. (1993) Plant Mol. Biol. 23, 401-407). This report describes the identification and enzymatic characterization of the cytosolic isoforms of GS in maize roots, namely GS1 and GSr. The purified isoforms, as well as recombinant enzymes that had been overexpressed in Escherichia coli, were analyzed by capillary liquid chromatography/electrospray ionization-mass spectrometry, and GS1 and GSr were identified as the products of the GS1a/GS1b and GS1c/GS1d genes, respectively. Upon the addition of ammonia to the culture medium, significant amounts of GSr accumulated and a preferential increase in GS synthetase activity, as compared to GS transferase activity, was found in the root extract. Assays with the purified recombinant enzymes confirmed that the specific biosynthetic and synthetase activities of GSr were 1.6-fold higher than those of GS1. Marked differences in stability were also found between the two isoforms: GSr was more sensitive to heat than GS1 and octameric aggregates of the subunits of GSr were easily dissociated to monomers than those of GS1 at low concentrations of Mn2+ and Mg2+ ions. These characteristics of the ammonia-induced isoform of GS seem to be physiologically important for the primary assimilation of external ammonia by roots.

Ammonia↗
PubMed1996

Identification of the functional region on the superantigen Yersinia pseudotuberculosis-derived mitogen responsible for induction of lymphocyte proliferation by using synthetic peptides.

Yersinia pseudotuberculosis-derived mitogen (YPM) is the unique Gram-negative bacillary superantigen known. In order to identify the regions on the YPM molecule involved in its superantigenic activity, seven overlapping peptides of the entire YPM molecule were synthesized and tested to evaluate their effects on the YPM-induced proliferation of human peripheral blood lymphocytes. A peptide corresponding to the N-terminal amino acid sequence (1-23) was found to inhibit YPM-induced lymphocyte proliferation in a concentration-dependent manner. The N-terminal peptide was found to show no inhibition of the proliferation induced by the other superantigen (staphylococcal enterotoxin B) or the other T-cell mitogen pertussis toxin, indicating that the inhibition is specific to YPM-induced proliferation. Thus, we have identified the N-terminal region (1-23) of the YPM as one of the functional regions responsible for its superantigenic activity.

Amino Acid Sequence↗
PubMed1996

Suicide inactivation of porcine leukocyte 12-lipoxygenase associated with its incorporation of 15-hydroperoxy-5,8,11,13-eicosatetraenoic acid derivative.

Two isozymes of arachidonate 12-lipoxygenase, platelet-type and leukocyte-type, which were distinguished by their substrate specificities and primary structures, were investigated with reference to 'suicide' inactivation. Upon reaction with arachidonic acid the leukocyte-type enzyme was inactivated rapidly during the catalysis, whereas the platelet-type enzyme did not show such a rapid inactivation. The two 12-lipoxygenase isozymes were incubated with various hydroperoxy and hydroxy products from arachidonic acid. (15S)-Hydroperoxy-5,8,11,13-eicosatetraenoic acid (15-HPETE) was found to be a unique substrate of the leukocyte-type 12-lipoxygenase as follows. (1) 15-HPETE was an active substrate for porcine leukocyte 12-lipoxygenase, and converted anaerobically to a 14,15-epoxy compound (14,15-leukotriene A4). (2) A rapid inactivation of the enzyme was observed within 2 min upon aerobic and anaerobic incubations with 15-HPETE. (3) 15-HPETE was rapidly incorporated into the enzyme in a nearly equimolar amount under both aerobic and anaerobic conditions. (4) Several findings suggested a covalent binding of 15-HPETE or its derivative to the enzyme. (5) Such a rapid and stoichiometric incorporation of 15-HPETE was not observed with the platelet-type 12-lipoxygenase. On the basis of these findings we presumed that 15-HPETE was transformed to 14,15-leukotriene A4, which was covalently bound to the leukocyte-type 12-lipoxygenase leading to the suicide inactivation of the enzyme.

Animals↗
PubMed1996

Effect of the position of a basic amino acid on C-terminal rearrangement of protonated peptides upon collision-induced dissociation.

Internal rearrangement involving the loss of the C-terminal amino acid residue upon collision-induced dissociation (CID) or metastable decomposition was studied for protonated peptides. To investigate the structural characteristics of peptides responsible for this rearrangement, a series of synthetic peptides were prepared and subjected to B/E-linked scan or tandem mass spectrometric analyses using a four-sector instrument. The results showed that the position of a basic amino acid in the peptide sequence and its basicity have a significant influence on the rearrangement. Arginine (Arg) located at the n-1 position facilitates the rearrangement with about twice as many rearrangement ions as is observed for the other Arg-containing peptides. This can be attributed to the interaction of a positively charged guanidino group of Arg with its own carbonyl group via a salt bridge which is tightly formed in vacuo between a guanidino and carboxylate groups, the mechanism of which is analogous to that previously proposed for the formation of similar rearrangement ions observed in the spectra of metal-cationized peptides. This association would result in the facile attack of the C-terminal hydroxyl group on the penultimate carbonyl group, leading to the rearrangement. In addition, the rearrangement ion was observed both in metastable decomposition and high-energy CID spectra obtained by B/E-linked scan analyses without or with gas, respectively, but in a sequence dependent manner.

Amino Acid Sequence↗
PubMed1996

Preparation and characterization of monoclonal antibodies specific for lauroylated isoform of bovine transducin alpha-subunit: immunohistochemical analysis of bovine retinas.

The photoreceptor G protein transducin [alpha- and beta gamma-subunits (T alpha/T beta gamma)] plays a central role in the visual transduction process. The amino-terminus of bovine T alpha is modified by one of four distinct fatty acids-laurate (C12:0), myristate (C14:0), C14:1 (5-cis), and C14:2 (5-cis, 8-cis)-but the biological significance and the localization of the four isoforms of T alpha are poorly understood. To investigate the cellular distribution of each isoform, we prepared monoclonal antibodies against a synthetic C12:0-, C14:0-, C14:1-, or C14:2-nonapeptide corresponding to the N-terminal region of T alpha. Among several types of antibodies isolated, only one type, represented by LA4, reacted specifically with the C12:0-peptide as well as purified T alpha but not with the other proteins in bovine retinal homogenate, including recoverin, indicating that the epitope comprises both C12:0 and the N-terminal amino acids of T alpha. Immunohistochemical analyses of bovine retinal sections by LA4 showed the uniform distribution of C12:0-T alpha in almost all the rod outer segments. Hence, it seemed unlikely that each isoform of T alpha was localized in specific cells. This observation, together with evidence for a possible functional diversity among the isoforms, suggests that the four isoforms of T alpha in a single rod cell may contribute simultaneously to a fine tuning of the photon-signal transduction process.

Acylation↗
PubMed1996

Hypothalamic-pituitary-adrenal axis in WBN/Kob rats with non-insulin dependent diabetes mellitus.

In an attempt to define the hypothalamic-pituitary-adrenal (HPA) axis in non-insulin dependent diabetic rats (WBN/Kob), we measured plasma corticotropin releasing factor (CRF), as well as arginine vasopressin (AVP), ACTH, and corticosterone (B), CRF concentrations in the median eminence (ME), the remainder of the hypothalamus (rHY) and the neurointermediate lobe of the pituitary (NIL). We also measured Iodine-125-labeled ovine CRF ([125I]oCRF) binding in the brain and peripheral tissues. Body and thymus weight in WBN/Kob rats were significantly lower than in control Wistar rats, but adrenal weight was higher in WBN/Kob rats. Plasma ACTH levels were significantly higher in WBN/Kob rats than in the control rats. However, plasma CRF, AVP and B levels in WBN/Kob rats were not different from those in the control rats. The CRF concentration was significantly decreased in the ME of the diabetic rats, compared with control rats, but CRF concentrations in the rHY and NIL were unchanged in the two groups. A significant reduction in [125I]oCRF binding in the anterior pituitary was demonstrated in WBN/Kob rats, but no significant difference between the diabetic and control rats in CRF binding was observed in the frontal cortex, spleen or adrenal gland. These findings suggest that the HPA axis is chronically stimulated in the non-insulin dependent diabetic rats.

Adrenal Glands↗
PubMed1996

Differential changes of corticotropin releasing hormone (CRH) concentrations in plasma and synovial fluids of patients with rheumatoid arthritis (RA).

Corticotropin releasing hormone (CRH) and ACTH concentrations in plasma and CRH and IL-6 concentrations in synovial fluid in patients with rheumatoid arthritis (RA) were examined to clarify the relationship between cytokines and the hypothalamic-pituitary-adrenal axis (HPA axis). Concentrations of serum amyloid A protein (SAA), one of the acute phase proteins, were also measured as an indicator of inflammation. CRH and IL-6 concentrations in synovial fluid were higher in RA patients than in control patients (osteoarthritis, OA). Plasma ACTH and CRH levels were significantly lower in RA patients than in OA patients. This suggests that CRH secretion in synovial fluid is regulated differently from plasma CRH secretion, as CRH levels in synovial fluid and plasma showed opposite changes in RA patients. SAA levels were positively correlated with the levels of CRH or IL-6 in synovial fluid, whereas there was no correlation between CRH and IL-6 levels. The results suggest that CRH and IL-6 play important independent roles in producing SAA in synovial fluid.

Adrenocorticotropic Hormone↗
PubMed1996

Secretion of anterior pituitary hormones in patients with insulin-dependent diabetes mellitus and polyglandular autoimmune syndrome.

We extracted gammaglobulins from the serum of 10 patients with insulin-dependent diabetes mellitus (IDDM) to investigate their effect on anterior pituitary hormone secretion using cultures of rat anterior pituitary cells. Three of the 10 patients also had the polyglandular autoimmune syndrome (PGA) type III with an isolated failure of anterior pituitary hormone secretion. The gammaglobulin from each of the 3 patients with PGA and an isolated failure of secretion of adrenocorticotropic hormone (ACTH), thyroid stimulating hormone (TSH) or gonadotropin inhibited the secretion of ACTH, TSH or gonadotropin in cultures of rat anterior pituitary cells. The gammaglobulins obtained from the other 7 patients with IDDM also showed an inhibitory or stimulatory effect on anterior pituitary hormone secretion in vitro. We postulate that some patients with IDDM, especially those with other endocrine autoimmune diseases, may have substances in their gammaglobulin fraction that can affect the secretion of anterior pituitary hormones.

Adrenocorticotropic Hormone↗
PubMed1996

[A case report--congenital esophago-bronchial fistula with esophageal diverticulum].

Congenital esophago-bronchial fistula with diverticulum is rare, and in Japan only 29 cases have been reported. A 59-year-old man had suffered from recurrent pulmonary infections and often complained of coughing while drinking water during the previous two years. An UGI series for follow-up of gastric ulcer revealed an esophago-bronchial fistula, located between the mid-esophagus and B10 of the right lung. We resected the diverticulum and the fistulous tract with a partial excision of S10. Histological examination revealed that the squamous epithelium with the muscularis mucosa of the esophagus was smoothly connected to the columnar epithelium of the bronchus. Thus, we diagnosed this fistula as congenital, not acquired. Comparison of the previous UGI series before presenting symptoms with that performed at this admission showed the lengthening and thickening of this congenital fistula during the three-years period. We suspected that the influence of acquired factors may cause a congenital fistula to manifest various clinical symptoms.

Adult↗
PubMed1996

[Effects of intra-hepatic arterial injection of mitoxantrone for hepatocellular carcinoma].

Twenty patients with unresectable hepatoma, recurrent hepatoma or metastatic liver cancer were treated by intra-hepatic arterial injection of mitoxantrone, and its effectiveness and side effects were studied. In 35.5% of the patients, complete or partial responses were seen. The survival intervals after the beginning of therapy were from one to 21 months (mean, 9.4 months) and one-year survival ratio was 56.3%. Red blood cell, leukocyte, and platelet counts diminished significantly one week later after administration of mitoxantrone compared with the pre-administration levels. Severe hepatic dysfunction has not been experienced.

Adult↗
PubMed1995

Interleukin-1 receptors in the brain-endocrine-immune axis. Modulation by stress and infection.

In the present study, we examined the in vitro and in vivo modulation of IL-1 receptors by stress and endotoxin treatment. The treatment of AtT-20 mouse pituitary adenoma cells for 24 h with neuroendocrine mediators of stress such as CRF and catecholamines produced dose-dependent increases in cAMP production and [125I]IL-1 alpha binding. In contrast, somatostatin and dexamethasone significantly inhibited CRF-stimulated cAMP production and decreased both basal and CRF-mediated increases in [125I]IL-1 alpha binding. Furthermore, in keeping with the effects of stress mediators to up-regulate IL-1 receptors in AtT-20 cells, ether-laparotomy stress in mice resulted in a significant increase in [125I]IL-1 alpha binding in the pituitary with no significant alterations observed in the brain; in contrast, [125I]oCRF binding in the pituitary was significantly decreased after the ether-laparotomy stress. Next, we investigated the modulation of IL-1 beta levels and [125I]IL-1 alpha binding following endotoxin treatment. IL-1 beta levels were dramatically increased in the peripheral tissues (pituitary, testis, and spleen) at 2-6 h after a single LPS injection (30 micrograms LPS/mouse); however, no significant changes were observed in brain (hippocampus and hypothalamus). [125I]IL-1 alpha binding in the pituitary gland, liver, spleen, and testis was significantly decreased at 2 h following a single administration of both low (30 micrograms LPS/mouse) and high (300 micrograms LPS/mouse) doses of endotoxin. [125I]IL-1 alpha binding in the hippocampus was not significantly altered at 2 h by low dose of LPS and was significantly decreased by high-dose administration of LPS (300 micrograms/mouse). Following two LPS injections (at 0 and 12 h), dramatic increases in IL-1 beta concentrations in the hypothalamus, hippocampus, spleen, and testis were observed at 2 h after the second LPS injection; a small but statistically nonsignificant change was evident in the pituitary. Moreover, dramatic decreases in [125I]IL-1 alpha binding were seen after two injections of 30 micrograms LPS/mouse in both central and peripheral tissues. These data provide further support for a role for IL-1 in coordinating brain-endocrine-immune responses to stress and infection.

Animals↗