Biomedical subjects
H Takeuchi
Publications and source records attributed to H Takeuchi.
[Prevalence of upper urinary tract stones in Tajima, north Hyogo, Japan].
Toyooka Hospital is a central hospital in Tajima, a rural area in the northern part of Hyogo Prefecture. Because we possess the sole lithotripter in this area, almost all urolithiasis patients requiring treatment have been referred to our department. Based on the number of urolithiasis patients treated in our institution, we estimated the annual prevalence and incidence of upper urinary tract stones in the Tajima area. The mean annual prevalence of urolithiasis and incidence during the 1991-1993 period were 141 and 93 per 100,000, respectively. The male to female ratio was 2.0 to 1 in prevalence and 2.2 to 1.0 in incidence. Prevalence was highest in the sixties (245) and fifties (235), followed by the forties (205), seventies (162) and thirties (160). The incidence was highest in the fifties (169), followed by the forties (147), sixties (145) and thirties (118). In consideration of sex, the incidence was highest in males in the fifties and the forties. Of the patients with upper urinary calculi, 23.1% were treated by extracorporeal shock wave lithotripsy, while in 23.8% stones passed spontaneously and 50.9% were followed up without treatment. On stone analysis, calcium oxalate and/or calcium phosphate was present in 75.6%, uric acid in 16.4%, struvite and/or carbonate apatite in 5.6% and cystine in 1.4%. In summary, the prevalence and incidence of upper urinary tract calculi in the Tajima area were considerably higher than those in the nationwide survey on urolithiasis in Japan conducted in 1985.
[Bilateral breast metastases from prostatic carcinoma: a case report].
We report a case of bilateral breast metastases from prostatic carcinoma. A 49-year-old man with stage D2 prostate cancer, who had been treated by chemoendocrine therapy and radiotherapy for 2 years, complained of bilateral enlarged breasts. Oral administration of diethylstilbestrol diphosphate was started 2 months before the onset of this symptom. A firm mass that was not tender was palpable beneath the skin without fixation on each side. A needle biopsy of the masses showed poorly differentiated adenocarcinoma with positive immunohistopathological staining for prostate-specific antigen. The masses were diagnosed as metastatic adenocarcinoma of prostate gland origin. The patient died 3 months after the diagnosis of breast metastases. Autopsy revealed diffuse lymphogenous metastatic disease. Metastatic prostatic carcinoma to the breast is uncommon. Breast metastases in this patient might be associated with diffuse lymphogenous metastases as well as increased local blood and lymphatic supply caused by extrinsic estrogens.
Effects of thromboxane synthetase inhibitor (RS-5186) on experimentally-induced cerebral vasospasm.
RS-5186, which inhibits thromboxane A2 (TXA2) synthetase activity, ameliorated delayed cerebral vasospasm in a canine two-hemorrhage model. Subarachnoid hemorrhage was induced in 15 dogs, which were divided into two groups. In the RS-5186-treated group (9 dogs), 50 mg kg-1 of RS-5186 was administered twice a day for seven days. The remaining six dogs without administration of RS-5186 were used as a control group. In the RS-5186-treated group, the angiographic diameter of the basilar artery on Day 7 after subarachnoid hemorrhage was constricted to 60.9% +/- 11.6% (n = 9, mean +/- SD) of that on Day 0, before subarachnoid hemorrhage. The corresponding value was 42.8% +/- 6.1% (n = 6) in the control group. There was a statistically significant difference between these percentages. In the RS-5186-treated group, plasma thromboxane B2 level on Day 7 was 144.3 +/- 28.1 pg ml-1 (n = 4), which was lower than the 815.5 +/- 162.0 pg ml-1 (n = 4) in the control group (p < 0.0005). The plasma 6-keto-prostaglandin F1 alpha level on Day 7 was 180.5 +/- 66.5 pg ml-1 (n = 4) in the RS-5186-treated group, and higher than 107.3 +/- 12.4 pg ml-1 (n = 4) in the control group (p = 0.0734). Thus, administration of RS-5186 reduced TXA2 plasma level and had a beneficial effect on angiographically-detected delayed vasospasm.
Social environmental factors in Japan affecting the development of proper eating behaviors.
This article summarizes issues related to myofunctional disorders/dysphagia and focuses upon social and economic changes within Japanese culture affecting eating habits and behaviors in children. The authors suggest that unfavorable environmental factors negatively impact upon the acquisition of mastication and swallowing behaviors. The article includes discussion of prior research. Studies indicate that decreased observation of early childhood eating habits, dietary changes with regard to higher consumption of fast food and changes within the family, i.e. busy work schedules, decrease in family mealtimes, combine to incur negative change with regard to orofacial function.
Localization of a novel inositol 1,4,5-trisphosphate binding protein, p130 in rat brain.
We have isolated a novel inositol 1,4,5-trisphosphate binding protein with molecular mass of 130 kDa (p130), homologous to phospholipase C-delta1 in amino acid sequence but with no catalytic activity. Here we report the expression and localization of p130 at the mRNA level in rat brain. Northern blotting showed that gene expression encoding p130 was most abundant in brain. Brain localization of p130-mRNA using an in situ hybridization technique revealed that in the cerebellum, the mRNA was detected in the granular cell and Purkinje cell layers, and cerebellar nuclei. In the cerebrum, the mRNA was localized in hippocampal pyramidal cells, dentate granule cells and pyramidal and/or granule cells of the cerebral cortex. The brain localization of p130-mRNA was similar to that of the beta-subtype of phospholipase C, indicating that p130 may be mainly involved in phospholipase Cbeta-mediated signaling.
Structural characteristics of bullfrog (Rana catesbeiana) transthyretin and its cDNA--comparison of its pattern of expression during metamorphosis with that of lipocalin.
Transthyretin, an extracellular thyroid-hormone-binding protein (THBP) in higher vertebrates, is synthesized and secreted by the choroid plexus of all classes of vertebrates, except fish and amphibians, and synthesized in the liver of endothermic animals. Here, we report the nucleotide sequence of the cDNA for a THBP found in plasma of bullfrog (Rana catesbeiana) tadpoles before the climax of metamorphosis. The amino acid sequence clearly shows this protein to be an amphibian transthyretin. The three-dimensional structure of bullfrog transthyretin was derived using homology modeling. Compared with transthyretins from other vertebrate species, bullfrog transthyretin is highly conserved at the thyroid hormone-binding sites and other important structural regions of the subunits. Bullfrog transthyretin mRNA was found in tadpole liver, but not in tadpole choroid plexus. Thus, during evolution, synthesis of transthyretin in the liver of metamorphosing amphibians preceded that in the choroid plexus of reptiles, birds and mammals. It was previously observed that the protein most abundantly synthesized and secreted by the choroid plexus in adult amphibians is a lipocalin [Achen, M. G., Harms, P. J., Thomas, T., Richardson, S. J., Wettenhall, R. E. H. & Schreiber, G. (1992) J. Biol. Chem. 267, 23170-23174], in contrast to transthyretin being the most abundantly synthesized and secreted protein in the choroid plexus of mammals, birds and reptiles. Lipocalin mRNA was found in large amounts in tadpole choroid plexus, but not livers.
PTB domain of insulin receptor substrate-1 binds inositol compounds.
We examined whether a phosphotyrosine binding (PTB) domain from the human insulin receptor substrate-1 (hIRS-1) is capable of binding inositol phosphates/phosphoinositides. The binding specificity was compared with that of the pleckstrin homology (PH) domain derived from the same protein because the three dimensional structure was found to be very similar to that of the PH domain, despite the lack of sequence similarity. We also attempted to locate the site of binding of the inositol compounds. The PTB domain bound [3H]Ins(1,4, 5)P3, which was displaced most strongly by Ins(1,3,4,5,6)P5 and InsP6, indicating that these inositol polyphosphates show the highest affinity. The PTB domain bound to liposomes containing PtdIns(4,5)P2, PtdIns(3,4,5)P3 and PtdIns(3,4)P2, but not phosphatidylinositol. In contrast, the PH domain showed a preference for Ins(1,4,5)P3, the polar head of PtdIns(4,5)P2. Site-directed mutagenesis studies were performed to map the binding site for inositol phosphates in the PTB domain. Mutation of K169Q, K171Q or K177Q, located in the loop connecting the beta1 and beta2 strands, which is partially responsible for binding inositol phosphates/phosphoinositides in the PH domains of several other proteins, reduced binding activity, probably because of a reduction in affinity. Mutation of R212Q or R227Q, shown to be involved in the binding of a phosphotyrosine, had little effect on the binding capacity. These results indicate that the PTB domain of hIRS-1 can bind inositol phosphates/phosphoinositides. Therefore signalling through the PTB domain could be regulated by the binding not only of proteins with phosphotyrosine but also of inositol phosphates/phosphoinositides, implying that PTB domains could be involved in a myriad of interconnections between intracellular signalling pathways.
Involvement of proteasomes in migration and matrix metalloproteinase-9 production of oral squamous cell carcinoma.
We investigated whether proteasomes were involved in the invasiveness of oral squamous cell carcinoma (SCC) cells. The migration of SCC cells through a gelatin-coated membrane was enhanced with tumor necrosis factor alpha (TNF alpha), which was strongly inhibited by a peptide aldehyde, N-acetyl-Leu-Leu-norleucinal (ALLN), but not by its structurally related compound, N-acetyl-Leu-Leu-methioninal (ALLM). Since ALLN is a more potent inhibitor against proteasomal proteolysis than ALLM, cell migration inhibited by ALLN may thus likely depend on proteasomes. The TNF alpha-induced migration through gelatin appeared to be associated with the gelatinolytic activity from the cells, since TNF alpha strongly enhanced the production of matrix metalloproteinase (MMP)-9/gelatinase B in the SCC cells, as detected by gelatin zymography. The production of MMP-9 was also inhibited by pretreatment with ALLN, but not ALLM, in a dose-dependent manner. Moreover, ALLN could block the activation and nuclear translocation of a transcription-activating factor, NF-kappaB, which is known to regulate MMP-9 expression in TNF alpha-stimulated SCC cells. The TNF alpha-induced degradation of IkappaB alpha was also suppressed by ALLN treatment, thus implying that the molecule linking proteasome to MMP-9 production should be IkappaB alpha. We finally reconfirmed the involvement of proteasomes in the invasive behavior of oral SCC using lactacystin, a specific proteasome inhibitor, which could prevent TNF alpha from enhancing MMP-9 production, NF-kappaB activation, induction of MMP-9 mRNA and cell migration.
Reversal of tolerance to human MUC1 antigen in MUC1 transgenic mice immunized with fusions of dendritic and carcinoma cells.
Immunological unresponsiveness established by the elimination or anergy of self-reactive lymphocyte clones is of importance to immunization against tumor-associated antigens. In this study, we have investigated induction of immunity against the human MUC1 carcinoma-associated antigen in MUC1 transgenic mice unresponsive to MUC1 antigen. Immunization of adult MUC1 transgenic mice with irradiated MUC1-positive tumor cells was unsuccessful in reversing unresponsiveness to MUC1. By contrast, fusions of dendritic cells with MUC1-positive tumor cells induced cellular and humoral immunity against MUC1. Immunization with the dendritic cell fusions that express MUC1 resulted in the rejection of established metastases and no apparent autoimmunity against normal tissues. These findings demonstrate that unresponsiveness to the MUC1 tumor-associated antigen is reversible by immunization with heterokaryons of dendritic cells and MUC1-positive carcinoma cells.
Role of metal-ligand coordination in the folding pathway of zinc finger peptides.
In the zinc fingers of TFIIIA family, two cysteines near the N-terminus and two histidines near the C-terminus are conserved for each finger unit. A cooperative binding of these residues to a Zn(II) ion is essential for the formation of the finger structure consisting of an anti-parallel beta-sheet and an alpha-helix. In order to reveal the folding pathway of the zinc finger, we have investigated, by Raman spectroscopy, the relationship between Zn(II)-ligand binding and conformational change of a 27-mer peptide representing the third finger of mouse transcription factor Zif268. In the absence of Zn(II), the peptide assumes a beta-sheet-rich structure. Upon addition of Zn(II), cysteines preferentially bind to Zn(II) prior to the metal coordination of histidines. Both the Zn(II)-cysteine and Zn(II)-histidine binding induce a partial secondary structure transition from beta-sheet to alpha-helix. Exchange of the ligand amino acid residues, i.e., cysteines to histidines and vice versa, produces a striking effect on the folding of the peptide. The beta-sheet-->alpha-helix transition is induced only by the Zn(II)-cysteine binding and the ligand exchanged peptide is not capable of folding into the finger structure. The present results demonstrate the importance of the ligand arrangement in the folding of zinc finger.
Preferential expression of the gene for a putative inositol 1,4,5-trisphosphate receptor homologue in the mushroom bodies of the brain of the worker honeybee Apis mellifera L.
A gene expressed preferentially in the mushroom bodies of the brain of the worker honeybee Apis mellifera L. was identified by the differential display method and its cDNA was isolated. The cDNA fragment of 534 bp (clone A1) contained an open reading frame encoding 177 amino acid residues having 78, 72, 70, 59 and 55% sequence identities with the inositol 1,4,5-trisphosphate (IP3) receptors of Drosophila melanogaster, Xenopus laevis and humans (types 1, 2 and 3), respectively, suggesting that it encodes a putative IP3 receptor homologue of the honeybee. In situ hybridization revealed that the gene encoding clone A1 was expressed preferentially in the mushroom bodies and not in the optic lobes, antennal lobes and central bodies; in the mushroom body, it was expressed strongly in the large type Kenyon cells and weakly in the small type Kenyon cells. Reverse transcription polymerase chain reaction analysis showed that the gene was expressed strongly in the head and weakly in the antennae, legs, thorax, and abdomen. These results suggest that the A1 gene product plays a crucial role in neural transmission in the mushroom bodies of the worker bee brain.
Raman linear intensity difference of membrane-bound peptides: indole ring orientations of tryptophans 11 and 13 in the gramicidin A transmembrane channel.
A Raman linear intensity difference (RLID) method has been developed to determine orientations of chromophores in membrane-bound peptides and proteins. The method involves orientation of the peptide or protein in lipid bilayer membranes and measurement of intensity differences between Raman spectra excited with two orthogonal laser polarizations. Analysis of the RLID spectrum is simplified when the chromophore exhibits a vibrational mode for which the Raman band is enhanced through resonance with a single molecular electronic transition. To examine the indole ring orientations of Trp residues in the gramicidin A transmembrane channel, we have prepared analogues of gramicidin A, in which one of four Trp residues is replaced by deuterated Trp (Trp-2,4,5,6,7-d5). Two vibrational Raman bands omega(d)3 and omega(d)2 of deuterated Trp have been shown to gain intensity predominantly through resonance with the Bb and La electronic transitions, respectively, when excited at 244 and 257 nm. By examining the RLID spectra of the omega(d)3 and omega(d)2 bands of gramicidin A channels oriented in phospholipid bilayer membranes, we have determined the inclination angles of the Bb and La transition moments with respect to the channel axis in the absence and presence of Na+. The orientations of the Trp-11 and Trp-13 indole rings in the gramicidin channel structure have been derived from the inclination angles of the transition moments. The indole rings of Trp-11 and Trp-13, which are known to shift along the channel axis upon binding of Na+, do not reorient during their positional shifts.
Paclitaxel/carboplatin administration along with antiangiogenic therapy in non-small-cell lung and breast carcinoma models.
INTRODUCTION: With the introduction of new drugs, the efficacy of chemotherapy in non-small-cell lung cancer has been improving. The combination of paclitaxel and carboplatin has shown activity in this disease but is far from curative. METHODS: The antiangiogenic agent regimen of TNP-470/minocycline was added to treatment with paclitaxel and carboplatin alone and in combination in animals bearing the Lewis lung carcinoma. RESULTS: Administration of the antiangiogenic regimen prior to, during and after the cytotoxic therapy increased the tumor growth delay 1.6-fold and decreased the number of lung metastases to 20% of the number observed in the control animals. [14C]Paclitaxel, platinum from carboplatin and [14C]albumin levels were determined over a 24-h time course in tumors and normal tissues of animals bearing the Lewis lung carcinoma and pretreated with TNP-470/minocycline or not pretreated. There were higher levels of [14C]paclitaxel, platinum from carboplatin and [14C]albumin in the tumors and some normal tissues of the animals that had received TNP-470/minocycline compared with those that had not received TNP-470/minocycline, especially at the earlier time points. Administration of TNP-470/minocycline to animals bearing the EMT-6 mammary carcinoma increased the cytotoxicity of high-dose paclitaxel toward EMT-6 tumor cells and toward bone marrow CFU-GM. Administration of TNP-470/minocycline to animals bearing the EMT-6 mammary carcinoma also increased the cytotoxicity of carboplatin toward the EMT-6 tumor cells but did not affect the toxicity of carboplatin toward the bone marrow CFU-GM. CONCLUSIONS: The addition of TNP-470/minocycline to treatment with paclitaxel and carboplatin resulted in increased antitumor activity and efficacy and further investigation of this combination is warranted.
Allosteric effectors of hemoglobin as modulators of chemotherapy and radiation therapy in vitro and in vivo.
INTRODUCTION: A series of molecules designed to be allosteric effectors of hemoglobin were examined for their potential as radiation sensitizers in vitro and in vivo and for their potential as chemosensitizers in vivo as well as for their antimetastatic effect. RESULTS: At a concentration of 100 microM for 1 h prior to, during and for 1.5 h after radiation exposure, the allosteric effectors decreased the shoulder of the radiation survival curve of normally oxygenated EMT-6 cells and increased the slope of the radiation survival curves of hypoxic EMT-6 cells resulting in dose-modifying factors of 1.8 to 2.1. In vivo the allosteric effectors had antitumor activity against the Lewis lung carcinoma and produced primarily additive tumor growth delay when administered along with fractionated radiation therapy. When administered on days 4 through 18 after tumor implantation, the allosteric effectors, especially JP-7, RSR-13 and RSR-4, were highly effective antimetastatic agents in animals bearing Lewis lung carcinoma. In cell culture, simultaneous exposure to the allosteric effectors (at 100 microM) effectively sensitized EMT-6 cells to the effects of 4-hydroperoxycyclophosphamide, thiotepa and carboplatin. The allosteric effectors were not very cytotoxic toward EMT-6 tumor cells from tumors treated in vivo with single doses of each molecule nor were these agents very cytotoxic toward bone marrow CFU-GM taken from the same animals. CONCLUSIONS: It is likely that the allosteric effectors have a molecular target in addition to hemoglobin. Other possible targets include hydroxymethyl-glutaryl-CoA reductase or microsomal cytochrome b5.
Jasplakinolide: interaction with radiation and hyperthermia in human prostate carcinoma and Lewis lung carcinoma.
PURPOSE: Jasplakinolide is a novel natural product anticancer agent which acts by inducing overpolymerization of actin. The aim of the current study was to explore the activity of jasplakinolide with hyperthermia and radiation. METHODS: The response of human PC-3 and DU-145 prostate carcinoma cells and DU-145 xenografts and the response of the Lewis lung carcinoma to jasplakinolide were studied. RESULTS: Jasplakinolide was cytotoxic toward human prostate carcinoma cells, DU-145, PC-3 and LNCaP in culture, killing 1 log of cells with 0.8, 0.3 and 0.07 microM of drug in 24 h, respectively. The combination of jasplakinolide and hyperthermia resulted in primarily additive cell killing by the two modalities in the three prostate carcinoma lines. In combination with radiation, jasplakinolide produced some diminution in the shoulder of the survival curve of normally oxygenated PC-3 cells and was a radiation sensitizer of hypoxic DU-145 cells and hypoxic PC-3 cells. In vivo, jasplakinolide was an active antitumor agent against the Lewis lung carcinoma and the DU-145 prostate carcinoma xenograft. Jasplakinolide was a radiation sensitizer in the Lewis lung carcinoma. Jasplakinolide was also effective against the systemic Lewis lung carcinoma, decreasing lung metastases. Lung metastases were further decreased when jasplakinolide was administered along with radiation to the subcutaneous primary tumor. In the DU-145 tumor, the effects of jasplakinolide and fractionated radiation for 1 or 2 weeks appeared to be primarily additive. CONCLUSION: Jasplakinolide is an interesting new anticancer agent for which further study both as an anticancer agent and in combined modality regimens is warranted.
Simplified hepatic resection utilizing absorbable polyglycolic acid-based tape and other ligature apparatus.
Hepatic resection has been increasing in frequency in the management of metastatic or primary neoplasms of the liver. Although mortality for this procedure has steadily decreased, the associated morbidity remains high. Morbidity is mainly associated with operative time and blood loss, especially in jaundiced and cirrhotic patients. During hepatic resection, control of bleeding from various sources is the most important problem faced by surgeons. During conventional lobectomy, despite prior control of hepatic artery and portal vein to that lobe, bleeding still occurs from the opposite lobe or back flow from hepatic veins. We usually apply Pringle's maneuver for hemostasis, but consequently there is postoperative hepatic dysfunction. We have previously investigated methods for vascular occlusion at the site of liver resection. We developed a new absorbable polyglycolic acid-based tape (breadth, 3 mm; length, 70 cm) for use in hepatic mass ligation, as well as two types of ligature apparatus. Hemostasis was achieved with these devices, and all lobar, segmental, and non-anatomic resections were performed without prior control of the portal venous system, hepatic arterial inflow, and hepatic venous outflow before parenchymal resection. This significantly shortened the operative time, as well as decreasing the blood loss during hepatic resection, with consequent reduction of postoperative morbidity. The use of this absorbable tape may reduce the incidence of local infection, abscess formation, and septicemia.
Detection of Epstein-Barr virus infection in the epithelial cells and lymphocytes of non-neoplastic tonsils by in situ hybridization and in situ PCR.
Non-neoplastic tonsils were analyzed for detection of Epstein-Barr virus (EBV)-positive cells by in situ hybridization and in situ PCR. EBV-encoded small nuclear RNA 1(EBER1)-positive cells were found in 28.2% of the tonsils and were evenly localized in the extrafollicular area and within germinal centers. Latent membrane protein 1 (LMP1)-positive cells were also dispersed in the extrafollicular and germinal center. Using in situ DNA-DNA hybridization, the EBV-positive signals were observed in the upper epithelial cell layers of the tonsils. In addition, in situ PCR detected EBV DNA-positive cells in the lower epithelial cell layers and lymphoid cells.