2251
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Abstract
In vitro clonal analyses were performed to gain insight into the mechanisms that control development of neural crest-derived cardiac outflow tract mesenchyme of quail embryos. The cardiac neural crest originates from the posterior rhombencephalic neural tube. The cells leave the neural tube and migrate through the posterior visceral arches to the outflow tract of the heart, where they form the conotruncal ridges. Mesenchyme cells derived from the neural tube from somitic levels 1-3 contained 5 types of clone-forming cells. One class of clones contained up to 6 phenotypes; smooth muscle cells, connective tissue cells, chondrocytes, sensory neuron precursors, serotonergic (putative enteric) neurons, and pigment cells. Another type of clone was totally pigmented, containing melanocytes only, whereas a third type consisted entirely of smooth muscle cells. The remaining classes of clones contained 3 and 4 phenotypes, respectively. Subsequently, mesenchymal cells obtained from posterior visceral arches were cloned in vitro. The major observations from these experiments are the following. 1) The cells have lost the capacity to form sensory neurons. 2) The capacity to form pigment cells is lost as well. 3) Four types of morphologically distinguishable clones were found. The frequency of one type of clone that contains ectomesenchymal cells only (smooth muscle cells, connective tissue cells, and chondrocytes) increased from zero at Hamburger and Hamilton stage 19+/20 to 67% at stage 24, possibly giving rise to visceral arch-derived structures. The frequency of the other 3 types of clones decreased with progressing embryonic development, indicating that these clone-forming cells either pass through the visceral arches, and/or are being converted to cells with fewer developmental potentials.(ABSTRACT TRUNCATED AT 250 WORDS)
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2252
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Seto M, Shindo K, Ito K, Sasaki Y. Selective inhibition of myosin phosphorylation and tension of hyperplastic arteries by the kinase inhibitor HA1077. Eur J Pharmacol 1995; 276:27-33. [PMID: 7781692 DOI: 10.1016/0014-2999(94)00786-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
To examine possible alterations in myosin light chain phosphorylation in hyperplastic arteries, rabbit strips from right hyperplastic and left normal control carotid arteries were used for experiments 6 weeks after the ballooning procedure. When the hyperplastic artery was stimulated with various concentrations of K+ (10, 20, 30, 40 and 60 mM), the maximal tension in response to each concentration was significantly higher (P < 0.05) than that in the control artery. The maximal extent of myosin light chain phosphorylation induced by 60 mM K+ in the hyperplastic artery was also significantly higher than that in the control (55.1 +/- 4.1 vs. 45.1 +/- 3.2%, mean +/- S.D.). However, the [Ca2+]i response to elevated K+ in hyperplastic arteries was much the same as that in control arteries, when measured with fura-PE3. HA1077 (1-5-(isoquinolinesulfonyl)-homopiperazine), a protein kinase inhibitor, was about 3-5 times more effective in inhibiting the tension and myosin light chain phosphorylation induced by 60 mM K+ in the hyperplastic artery than in the control artery. Nifedipine inhibited the tension and myosin light chain phosphorylation to the same extent in control and hyperplastic arteries. Thus, an alteration of the myosin light chain phosphorylation system, but not an alteration of Ca2+ mobilization, may be involved in the enhanced contraction of the hyperplastic artery. The enhanced phosphorylation of myosin light chain may be sensitive to HA1077.
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2253
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Nagai S, Kitani S, Hirai K, Takaishi T, Nakajima K, Kihara H, Nonomura Y, Ito K, Morita Y. Pharmacological study of stem-cell-factor-induced mast cell histamine release with kinase inhibitors. Biochem Biophys Res Commun 1995; 208:576-81. [PMID: 7535052 DOI: 10.1006/bbrc.1995.1377] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Stem cell factor (SCF) is a ligand for c-kit receptor and has a critical role in the development of mast cells. In this study, we investigated the effect of a panel of kinase inhibitors on SCF-induced histamine release from rat peritoneal mast cells. Genistein, an inhibitor of tyrosine kinases, inhibited SCF-induced histamine release with IC50 of 1.6 x 10(-5) M. Wortmannin, an inhibitor of phosphatidylinositol 3'-kinase (PI3 kinase), inhibited histamine release stimulated with SCF dose-dependently with IC50 of 4 x 10(-9) M. KT5926, an inhibitor of myosin light chain (MLC) kinase, reduced histamine release with IC50 of 1.8 x 10(-7) M. Staurosporine, an inhibitor of protein kinases, also inhibited SCF-induced histamine release with IC50 of 6.5 x 10(-8) M. These results show the early involvement of tyrosine kinase and PI3 kinase and the possible role of MLC kinase in the late secretory phase in the signaling pathway used by SCF.
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2254
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Shimoike T, Taura T, Kihara A, Yoshihisa T, Akiyama Y, Cannon K, Ito K. Product of a new gene, syd, functionally interacts with SecY when overproduced in Escherichia coli. J Biol Chem 1995; 270:5519-26. [PMID: 7890670 DOI: 10.1074/jbc.270.10.5519] [Citation(s) in RCA: 54] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
A mutant form of SecY, SecY-d1, was previously suggested to sequester a component(s) of the protein translocator complex. Its synthesis from a plasmid leads to interference with protein export in Escherichia coli. SecE is a target of this sequestration, and its overproduction cancels the export interference. We now report that overexpression of another gene, termed syd, also suppresses secY-d1. The nucleotide sequence of syd predicted that it encodes a protein of 181 amino acid residues, which has been identified by overproduction, purification, and determination of the amino-terminal sequence. Cell fractionation experiments suggested that Syd is loosely associated with the cytoplasmic surface of the cytoplasmic membrane. SecY may be involved in the membrane association of Syd since the association is saturable, the extent of which depends on the overproduction of SecY. SecY is rapidly degraded in vivo unless its primary partner, SecE, is sufficiently available. Overproduction of Syd was found to stabilize oversynthesized SecY. However, Syd cannot stabilize the SecY-d1 form of SecY. Thus, in the presence of both secY+ and secY-d1, Syd increases the effective SecY+/SecY-d1 ratio in the cell and cancels the dominant interference by the latter. We also found that overproduction of Syd dramatically inhibits protein export in the secY24 mutant cell in which SecY-SecE interaction has been weakened. These results indicate that Syd, especially when it is overproduced, has abilities to interact with SecY. Possible significance of such interactions is discussed in conjunction with the apparent lack of phenotypic consequences of genetic disruption of syd.
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2255
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Fujii S, Ito K, Osada H, Hamaguchi T, Kuroda Y, Kato H. Extracellular phosphorylation of membrane protein modifies theta burst-induced long-term potentiation in CA1 neurons of guinea-pig hippocampal slices. Neurosci Lett 1995; 187:133-6. [PMID: 7783960 DOI: 10.1016/0304-3940(95)11342-8] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The involvement of ecto-protein kinase activity in activity-dependent long-term potentiation (LTP) was studied in CA1 neurons of guinea-pig hippocampal slices. Application of 5 microM K-252b, an ecto-protein kinase inhibitor, blocked LTP induced by a theta-burst stimulation (3 bursts composed of 5 pulses at 100 Hz with inter-burst intervals of 200 ms). On the other hand, under 10 microM RK682, an ecto-phosphatase inhibitor, a robust LTP was induced by a weak theta-burst stimulation (3 bursts composed of 3 pulses) which was just at the threshold for the induction of LTP in the control perfusate. These findings suggest that ATP released from presynaptic terminals during the burst stimulation plays an important role in the induction of LTP through phosphorylation of extracellular domains of synaptic membrane proteins, as the substrate for ecto-protein kinase.
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2256
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Fujii S, Kato H, Furuse H, Ito K, Osada H, Hamaguchi T, Kuroda Y. The mechanism of ATP-induced long-term potentiation involves extracellular phosphorylation of membrane proteins in guinea-pig hippocampal CA1 neurons. Neurosci Lett 1995; 187:130-2. [PMID: 7783959 DOI: 10.1016/0304-3940(95)11347-9] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The mechanism of ATP-induced long-term potentiation was studied pharmacologically using guinea-pig hippocampal slices. Application of 1-10 microM ATP for 10 min transiently depressed and then slowly augmented the synaptic transmission in CA1 neurons leading to long-term potentiation (LTP). This ATP-induced LTP was blocked by the addition of K-252b, an ecto-protein kinase inhibitor, but was enhanced by the addition of RK682, an ecto-phosphatase inhibitor, both of which do not permeate the cell membrane. These results suggest that ATP applied to the perfusate provides enough substrate for ecto-protein kinase to induce LTP through phosphorylation of extracellular domains of membrane proteins in CA1 neurons.
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2257
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Ito K, Kodama R, Maeda M, Tsuji A. Highly Sensitive Non-Isotopic Immunoassays for Cholecystokinin Using Various Detection Methods. ANAL LETT 1995. [DOI: 10.1080/00032719508001425] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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2258
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Kyotani H, Shimomura M, Ito K, Tanabe Y, Zhang YX, Akagi K, Shirakawa H. Isothermal cis-trans isomerization behavior of polyacetylene films. ACTA ACUST UNITED AC 1995. [DOI: 10.1002/polb.1995.090330407] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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2259
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Ozaki O, Sugino K, Mimura T, Ito K. Surgery for patients with thyroid carcinoma invading the trachea: circumferential sleeve resection followed by end-to-end anastomosis. Surgery 1995; 117:268-71. [PMID: 7878531 DOI: 10.1016/s0039-6060(05)80200-4] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
BACKGROUND Curative surgery can be accomplished by tracheal resection in patients with thyroid carcinoma invading the trachea; however, there is controversy regarding the extent of the tracheal resection. In this study we investigated by means of histologic examination the mode of tracheal invasion by thyroid carcinoma. METHODS Twenty-one patients with thyroid carcinoma invading the trachea underwent circumferential sleeve resection of the involved trachea. The extent of invasion of the tracheal wall on the adventitial and mucosal sides was compared on histologic examination. RESULTS Three to nine tracheal rings were resected. Assessment of longitudinal spread showed that one to six rings (mean; 3.1 rings) were invaded on the adventitial side but only zero to four rings (mean; 1.9 rings) on the mucosal side, with invasion on the mucosal side never exceeding invasion on the adventitial side. In contrast, examination of circumferential spread showed invasion on the mucosal side exceeding invasion on the adventitial side in five cases. CONCLUSIONS Our results suggest that when the extent of invasion of the adventitia is considered, carcinoma tissue may be left behind on the mucosal side of the trachea when partial wedge resection is performed and that, whenever feasible, circumferential sleeve resection should be performed in patients with thyroid carcinoma invading the trachea.
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2260
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Suzuki K, Ito K, Ichinose Y, Kurokawa K, Suzuki T, Imai K, Yamanaka H, Honma S. Endocrine environment of benign prostatic hyperplasia: prostate size and volume are correlated with serum estrogen concentration. SCANDINAVIAN JOURNAL OF UROLOGY AND NEPHROLOGY 1995; 29:65-8. [PMID: 7542400 DOI: 10.3109/00365599509180541] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Estrogen plays an important role in the development of benign prostatic hyperplasia (BPH), as has been shown in both experimental and clinical studies. T determine the endocrine environment of BPH, serum total testosterone (Total-T), free testosterone (Free-T), and estradiol (E2) conceptions were measured, and the relationship between these levels and prostate size and volume was analyzed. Blood samples were collected from subjects who attended the mass screening for prostate disease performed by our institute. No significant correlations were found between Total-T levels, Free-T levels, and prostate size, as determined by digital rectal examination. However, E2 levels and the ratios for E2 levels and the ratios for E2/Total-T and E2/Free-T were significantly correlated with prostate size. To confirm these relationships, prostate volume was calculated from transrectal ultrasonographic images. E2 levels and these two ratios were, indeed, highly correlated with prostate volume. These results suggest that an estrogen-dominant environment plays an important role in the development of BPH.
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2261
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Ogawa M, Ueda S, Anzai N, Ito K, Akikusa B. Pauci-immune crescentic glomerulonephritis and cutaneous vasculitis associated with anti-proteinase 3 antibody. Clin Nephrol 1995; 43:209-10. [PMID: 7774085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
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2262
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Ito K. [Marsilio Ficino's theory on health]. NIHON ISHIGAKU ZASSHI. [JOURNAL OF JAPANESE HISTORY OF MEDICINE] 1995; 41:29-40. [PMID: 11639607] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Abstract
Marsilio Ficino, the most important philosopher of the Italian Renaissance, wrote a medical book "De vita". Its first part deals with the health of those who devote themselves to literary studies. On the basis of Galenian humoralism, Ficino argues that learned people or scholars are prone to phlegm and black bile. The excesses of them bring sickness, and particularly the excesses of black bile make scholars melancholic. Therefore they must be careful about the balance of humors. Ficino states that the insanity brought by black bile is 'divine madness', necessary to genial works. He finds the elements, which make 'sacred madness' different in quality from general madness, under the influence of the celestial world. We can find the truth by the guidance of Saturn. Black bile participates in the Saturnian quality: cold and dry, and transmits the characteristic of Saturn to us. We can understand the 'divine things' only by the Saturnian melancholy. Therefore the influence of planets is very important for the activity of scholars. Through "De vita", astrological medicine - which attributes the causes of disease to the celestial world - had a great influence on Renaissance thought, and made an important contribution to the theoretical explanation of epidemic diseases like pestilence and sphilis. Ficino's theory certified the nobility and divinity of the duties of intellectuals, and was the main theoretical source of the Renaissance characteristic view of genius.
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2263
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Mori A, Suko M, Nishizaki Y, Kaminuma O, Kobayashi S, Matsuzaki G, Yamamoto K, Ito K, Tsuruoka N, Okudaira H. IL-5 production by CD4+ T cells of asthmatic patients is suppressed by glucocorticoids and the immunosuppressants FK506 and cyclosporin A. Int Immunol 1995; 7:449-57. [PMID: 7540862 DOI: 10.1093/intimm/7.3.449] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
IL-5 was produced in vitro by peripheral blood mononuclear cells (PBMC) of mite-sensitive atopic patients upon challenge with specific allergen, while PBMC of healthy controls produced essentially no IL-5. Stimuli delivered by the combination of phorbol ester and Ca2+ ionophore induced marked IL-5 production by PBMC obtained from atopic and non-atopic asthmatics, suggesting that both protein kinase C and Ca2+ influx are required for IL-5 production. CD2- or CD4-bearing cell depletion almost completely removed IL-5-producing cells while CD8-bearing cell depletion rather enriched them. These findings indicate that CD4+ T cells are the principal source of IL-5 in PBMC. The capacity of PBMC of atopic asthmatics, non-atopic asthmatics and healthy controls to produce IL-2, IL-4, IL-5 and IFN-gamma was compared, to find that cytokine-producing capacities other than that of IL-5 (IL-2, IL-4 and IFN-gamma) were not significantly different among the three groups. Dexamethasone, FK506 and cyclosporin A suppressed IL-5 production in vitro in a dose-dependent manner. Clear dose-dependent suppression of IL-5 gene expression by FK506 was also observed. Treatment of asthmatic patients with inhaled glucocorticoid (beclomethasone dipropionate) ameliorated clinical symptoms, improved lung function and markedly suppressed IL-5 production by PBMC, suggesting the essential role of IL-5 in the pathogenesis of bronchial asthma and the clinical importance of its regulation.
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2264
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Ito K, Honjo K, Fujita T, Matsui M, Awaya H, Matsumoto T, Matsunaga N, Nakanishi T. Therapeutic efficacy of transcatheter arterial chemoembolization for hepatocellular carcinoma: MRI and pathology. J Comput Assist Tomogr 1995; 19:198-203. [PMID: 7890841 DOI: 10.1097/00004728-199503000-00006] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
OBJECTIVE Our goal was to evaluate the usefulness of multisection dynamic MRI with gadopentetate dimeglumine in the assessment of the therapeutic efficacy of transcatheter arterial chemoembolization (TAE) with iodized oil for hepatocellular carcinomas (HCCs). MATERIALS AND METHODS Findings on multisection dynamic MRI images were compared with gross appearance and histologic findings in 13 patients with HCCs after TAE with iodized oil. Arterial dominant phase images of the entire liver were obtained 20 s after the start of administration of gadopentetate dimeglumine. RESULTS In 3 of the 13 patients, no enhancing areas within the tumors were detected. In the remaining 10 patients, enhancing portions were detected within the tumor on arterial dominant phase images. Histologically, viable tumor cells were present in the rapidly enhancing portions, while necrotic tissues were present in nonenhancing areas, irrespective of the accumulation of iodized oil on CT scans. However, in one patient in whom no enhancing portion was seen in the tumor, a small number of viable tumor cells within the capsule were identified on pathologic examination. CONCLUSION Multisection dynamic MRI is helpful for evaluating the therapeutic efficacy of TAE with iodized oil for HCCs by revealing the hemodynamics of the tumor irrespective of accumulation of iodized oil.
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2265
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Ito K, Maruyama H, Hirose H, Kido K, Koyama K, Kataoka K, Saruta T. Exogenous insulin dose-dependently suppresses glucopenia-induced glucagon secretion from perfused rat pancreas. Metabolism 1995; 44:358-62. [PMID: 7885281 DOI: 10.1016/0026-0495(95)90166-3] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
To clarify the role of insulin in modulating the glucagon response to glucose concentration changes, we investigated the effects of exogenous insulin (10 mU/mL, 100 mU/mL, and 3.3 U/mL) on responses to high glucose (5.6-->16.7 mmol/L), low glucose (5.6-->1.4 mmol/L), and arginine (10 mmol/L) stimulation using the perfused rat pancreas. Although glucagon levels were slightly suppressed by all of the exogenous insulin concentrations tested for the initial few minutes at 5.6 mmol/L glucose, baseline levels were maintained thereafter. Glucagon responses to high or normal glucose concentrations were not altered, but glucopenia-induced glucagon secretion was significantly suppressed as compared with that of controls (0.77 +/- 0.14 ng/min [10 mU/mL, n = 5], 0.55 +/- 0.14 ng/min [100 mU/mL, n = 5], 0.27 +/- 0.13 ng/min [3.3 U/mL, n = 5] v 1.38 +/- 0.20 ng/min [controls, n = 9], P < 0.05, respectively). The first phase of the glucagon response to arginine was potentiated (2.03 +/- 0.24 v 1.17 +/- 0.22 ng/min, P < .05) by 10 mU/mL exogenous insulin. The second phase of the glucagon response to arginine was significantly suppressed in the presence of higher concentrations of exogenous insulin (1.16 +/- 0.23 ng/min [100 mU/mL], 0.96 +/- 0.08 ng/min [3.3 U/mL] v 1.57 +/- 0.17 ng/min, P < .05, respectively). These results suggest that glucagon secretion is modified by the combined suppressive effects of glucose and insulin, although it is mainly glucose that mediates glucagon secretion in the physiological glucose range. Glucopenia- or arginine-induced glucagon secretion is suppressed by insulin.
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2266
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Toyama H, Ito K, Komori Y, Sugioka A, Shibata K, Komai S, Fujiwara T, Ishikawa E, Tomita K, Fujii N. [Evaluation of the residual functional reserve and the early regeneration after the hepatic resection using asialoglycoprotein receptor imaging agent]. KAKU IGAKU. THE JAPANESE JOURNAL OF NUCLEAR MEDICINE 1995; 32:323-9. [PMID: 7739162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
99mTc-DTPA-galactosyl human serum albumin (99mTc-GSA) is a newly developed liver imaging ligand which specifically binds to asialoglycoprotein receptor on the hepatic cell surface. We investigated whether 99mTc-GSA scintigraphy was able to be used as indexes for the residual functional reserve and the early regeneration of the hepatocyte after the hepatic resection. Four patients with metastatic liver cancer, 3 patients with hepatocellular carcinoma, and 1 patient with cholangiocellular carcinoma were studied. Basically, each patient was examined 4 times (before, 3, 10, 20 days after the operation). Immediately after i.v. injection of 185 MBq (3 mg) of 99mTc-GSA, serial images and dynamic data were obtained. Serial changes of HH15, as an index of blood clearance of the tracer calculated from the uptake ratio of heart at 15 minutes to that at 3 minutes, and LHL15, as an index of hepatic accumulation calculated from the uptake ratio of liver to liver plus heart at 15 minutes after the injection were analyzed before and after hepatectomy. Three out of 4 lobectomy patients which showed increased HH15, and decreased LHL15 as compared with the preoperative data were considered to be decreased residual hepatic functional reserve. The remaining one lobectomy patient showed increased HH15, but increased LHL15 inversely. One patient of two partial resections of hepatocellular carcinoma with liver cirrhosis demonstrated transiently decreased HH15, and increased LHL15. Two patients with metastatic liver cancer (one partial resection, six partial resections) showed decreased HH15, and increased LHL15. Postoperatively increased hepatic accumulation was presumed to be increased functioning hepatocyte or transiently increased asialoglycoprotein receptor on the cell surface by up-regulation. 99mTc-GSA scintigraphy might be helpful for non-invasive method to detect the residual functional reserve and the early regeneration of the hepatocyte after the hepatic resection.
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2267
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Hirose H, Maruyama H, Seto Y, Ito K, Fujita T, Dan K, Kanda N, Saruta T, Kato R. Effects of D-phenylalanine-derivative hypoglycemic agent A-4166 on pancreatic alpha- and beta-cells: comparative study with glibenclamide. Pharmacology 1995; 50:175-81. [PMID: 7746834 DOI: 10.1159/000139280] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
We have reported that N-[(trans-4-isopropyl-cyclohexyl)-carbonyl]-D-phenylalanine (A-4166) stimulates insulin secretion in animal studies. To further elucidate the mechanisms underlying the actions of this agent, we investigated the effects of A-4166 on insulin and glucagon secretion with or without diazoxide, an ATP-sensitive potassium channel opener, using isolated perfused rat pancreas preparations, and compared the results with those of glibenclamide. Both 30 mumol/l A-4166 and 3 mumol/l glibenclamide significantly stimulated insulin secretion and reduced glucagon secretion to similar levels at a glucose concentration of 5.6 mmol/l (p < 0.01 for both vs. basal levels). After infusion of A-4166 was stopped, insulin levels promptly returned to the basal values, while insulin levels increased further even after discontinuation of glibenclamide. Furthermore, 100 mumol/l diazoxide significantly inhibited the insulin-stimulatory effects of both 30 mumol/l A-4166 and 3 mumol/l glibenclamide (p < 0.05 and p < 0.01, respectively). However, the effects of diazoxide on glucagon secretion differed between the two groups; 30 mumol/l A-4166 produced a transient increase in glucagon secretion (p < 0.05 vs. basal levels) but 3 mumol/l glibenclamide suppressed glucagon secretion further (p < 0.01 vs. without diazoxide) with concomitant administration of 100 mumol/l diazoxide. These findings suggest that A-4166 directly stimulates insulin secretion, at least in part, through mechanisms resembling those of sulfonylurea, but exerts different effect on glucagon secretion in isolated perfused rat pancreas.
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2268
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Saegusa T, Ito K, Oba N, Matsuda M, Kojima K, Tohyama K, Matsumoto M, Miura K, Suzuki H. Enlargement of multiple cavernous hemangioma of the liver in association with pregnancy. Intern Med 1995; 34:207-11. [PMID: 7787330 DOI: 10.2169/internalmedicine.34.207] [Citation(s) in RCA: 53] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Four cavernous hemangiomas were found in a 34-year-old woman after the first delivery. All four hemangiomas became enlarged after the second delivery. Due to complaints of symptoms of compression, and to rule out malignancy, surgical intervention was employed. Histologically, the tumors were typical cavernous hemangiomas. Although a relationship between enlargement of hemangiomas and estrogen was suggested, estrogen receptors were not detected in the tumors.
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2269
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Suzuki K, Ito K, Suzuki T, Honma S, Yamanaka H. Synergistic effects of estrogen and androgen on the prostate: effects of estrogen on androgen- and estrogen-receptors, BrdU uptake, immunohistochemical study of AR, and responses to antiandrogens. Prostate 1995; 26:151-63. [PMID: 7534918 DOI: 10.1002/pros.2990260307] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
To investigate the synergistic effects of estradiol (E2) and testosterone (T) on prostate growth, castrated Wistar rats were treated with 1 mg/day of T or with 1 mg/day of T and 0.01 mg/day of E2 for 6 weeks. The weight of the prostate in T + E2-treated rats was significantly higher than that in T-treated and normal rats, parallel with the bromodeoxy-uridine (BrdU) labeling index (LI). Nuclear androgen receptor (AR) content in the T + E2 group was significantly higher than that in the T group. But they were lower than that in normal rats. And there were no significant differences between the groups in nuclear estrogen receptor (ER) content. Immunohistochemical studies with the AR antibody revealed positive staining in the prostatic epithelium and stromal cells in the normal, T-treated, and T + E2-treated animals. However, castration led to loss of staining. Response to steroidal antiandrogens was also determined. Antiandrogen treatment abrogated the increases in nuclear AR content and BrdU LI, and prevented immunohistochemical staining. These results suggest that AR and ER, which were measured in this study, were not indicators of prostatic proliferation. We further need to investigate other factors, including other types of receptors, growth factors involved in epithelial-stromal interaction, and so on.
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2270
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Yoshimoto T, Tabira J, Kabashima T, Inoue S, Ito K. Protease II from Moraxella lacunata: cloning, sequencing, and expression of the enzyme gene, and crystallization of the expressed enzyme. J Biochem 1995; 117:654-60. [PMID: 7629037 DOI: 10.1093/oxfordjournals.jbchem.a124759] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
A gene coding for protease II (basic amino acid specific oligoendopeptidase) from Moraxella lacunata was cloned and expressed in Escherichia coli DH1. The transformant harboring a hybrid plasmid, pMPROII-12, with a 3.0-kbp insert at the PvuII-SacI site in pUC19, showed 23-fold higher enzyme activity than M. lacunata. The expressed enzyme from E. coli DH1/pMPROII-12 was purified by 40-80% ammonium sulfate fractionation, chromatography on DEAE-Toyopearl, and Sephadex G-150 gel filtration. The enzyme was most active at pH 6.5 and stable at pH 6.5-9.5. It had an optimum temperature of 35 degrees C for 5 min of reaction and was stable to up to 35 degrees C for 30 min at pH 7.0. Its molecular weight was estimated to be 80,000 by SDS-PAGE and gel-filtration analyses. It enzyme was inhibited by diisopropyl fluorophosphate (DFP) and classified as a serine endoprotease. Its amino acid sequence was 38% homologous to that of the E. coli protease II. By alignment with other members of the prolyl endopeptidase family, the amino acid residues involved in the catalytic triad were deduced to be Ser-534, Asp-619, and His-654. The enzyme was crystallized by the hanging drop vapor diffusion method using PEG 4000 as precipitant.
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2271
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Ito K, Kawaguchi H, Shizume K, Hibi I. [The effects of recombinant human growth hormone (r-hGH, SM-9500, genotropin) on growth disturbance in children after renal transplantation. Japanese Multi-Center Study (Genotropin) Group on Children with Renal Disease]. NIHON JINZO GAKKAI SHI 1995; 37:194-200. [PMID: 7731108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
We treated 27 children with renal transplantation who showed growth failure due to deteriorated graft function and/or corticosteroids therapy with recombinant growth hormone (r-hGH) to improve their growth disturbance. The dose of rhGH was either 0.5 or 1.0 IU/kg/week. After 12 months treatment of r-hGH, growth velocity was significantly increased in both groups. Growth velocity was improved from 5.0 +/- 2.9 cm/year to 7.7 +/- 2.3 cm/year, P < 0.05, in 0.51U group and 3.7 +/- 2.4 cm/year to 6.3 +/- 3.3 cm/year, P < 0.05, in 1.01U group. The most important side effect of r-hGH was relevant to graft function. 7 out of all 27 children showed deterioration of graft function. However only 2 children showed significant decreases in their graft function during r-hGH therapy. Thus we conclude that r-hGH therapy was effective to improve growth failure in uremic children even after renal transplantation due to poor graft function and/or corticosteroids therapy.
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2272
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Ito K, Kawaguchi H, Shizume K, Hibi I. [The effects of recombinant human growth hormone (r-hGH, SM-9500, genotropin) on growth failure in children with uremia. Japanese Multi-Center Study (Genotropin) Group on Children with Renal Disease]. NIHON JINZO GAKKAI SHI 1995; 37:186-93. [PMID: 7731107] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
We treated 90 pediatric patients with chronic renal failure with recombinant growth hormone (r-hGH) for 12 months to improve their growth retardation due to uremia. They were divided into two groups, non-dialyzed and dialyzed children. The dose of r-hGH was 0.5 or 1.0 IU/kg/week in dialyzed children. After 12 months of the treatment using r-hGH, growth velocity was significantly increased in any group of children. Growth velocity was stimulated to about twice as much as before treatment (that were: in non-dialyzed group, 4.2 +/- 2.6cm/year vs. 6.2 +/- 2.0cm/year, P < 0.05, in dialyzed children treated with 0.51U of r-hGH: 2.7 +/- 1.8cm/year vs. 5.2 +/- 2.6cm/year, P < 0.001, and in dialyzed children treated with 1.01U of r-hGH: 3.0 +/- 1.5cm/year vs. 6.3 +/- 2.2cm/year, P < 0.001). No severe side effects was noted and no disturbance of renal function. Our results were consistent with those reported from Europe and USA. We conclude that r-hGH treatment is very effective in improving retarded growth in children with renal disease.
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2273
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Haida M, Nomura Y, Ito K, Makino S, Miyamoto T. [Psychological profiles of patients with bronchial asthma (II). Analysis according to the modes of attack in severe asthmatics and in those with fatal asthma]. ARERUGI = [ALLERGY] 1995; 44:143-59. [PMID: 7646371] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
When the rise of asthma death became a world-wide problem, background factors proposed were the poor patient education and compliance with psychological factors which hindered these accomplishments. Analysis were made on the psychological test scales recorded by the severe asthmatics and found that the result for the acute type resembled the controls, while those with chronic attacks had depressive/neurotic tendencies with decreased activity. Result of those with acute on chronic attacks show more active attitude in life. Fatal asthmatics had high level for thinking extroversion signifying more optimistic attitude which may have lead them to their under-estimation of asthma. Other scales in fatal asthma suggest problems in their life styles and maladaptation.
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2274
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Ito K, Shiomi M, Kito G. Effects of the non-peptide angiotensin II receptor antagonist TCV-116 on systemic and renal hemodynamics in dogs with renal hypertension. Hypertens Res 1995; 18:69-75. [PMID: 7584913 DOI: 10.1291/hypres.18.69] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The effects of TCV-116, a new non-peptide angiotensin II receptor antagonist, on systemic and renal hemodynamics were studied in conscious normotensive and renal hypertensive (2-kidney, 1-clip Gold-blatt type) dogs. When orally administered at 0.03 to 1.0 mg/kg, TCV-116 inhibited the pressor response to angiotensin II in conscious normotensive dogs in a dose-dependent fashion. The IC50 and IC100 values were 0.06 mg/kg and 0.86 mg/kg, respectively. TCV-116 at doses of 0.3 mg/kg and 1.0 mg/kg dose-dependently and persistently decreased systolic and diastolic blood pressure in both dogs with acute renal (hyperreninemic) and those with chronic renal (normoreninemic) hypertension. Even a high dose of TCV-116 (10 mg/kg, p.o.) increased effective renal plasma flow without affecting blood pressure or glomerular filtration rate in normotensive dogs. Furthermore, even at this high dose, TCV-116 did not reduce effective renal plasma flow or glomerular filtration rate in dogs with renal hypertension despite marked reduction in systemic blood pressure. The angiotensin converting enzyme inhibitor enalapril (10 mg/kg, p.o.) had renal hemodynamic effects similar to those of TCV-116. These findings indicate that TCV-116 has potent hypotensive effects not only in dogs with acute renal hypertension but also in those with chronic renal hypertension, but does not appear to adversely affect renal hemodynamics.
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2275
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Kimura T, Yoshida S, Sato K, Kurokawa I, Nasu S, Ito K, Neriai Y, Fukuda M, Kondou M. [Relationship between left atrial spontaneous contrast echo and coagulofibrinolytic findings]. RINSHO BYORI. THE JAPANESE JOURNAL OF CLINICAL PATHOLOGY 1995; 43:275-80. [PMID: 7745834] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Transesophageal echocardiography (TEE) has been used to identify patients with left atrial thrombi (LAT) and spontaneous contrast echo (SCE). Patients with LAT or SCE are at high risk for cerebral embolism. The aim of this study was to examine the relationship between SCE detected with TEE [5MHz] and coagulation and fibrinolysis factors. We took blood samples from 83 patients to measure plasma levels of TAT, PIC, D-dimer, fibrinogen and thrombomodulin (TM) just before TEE examination. The patients were classified into four groups according to SCE grade based on echo density and area of the left atrium occupied by SCE. Plasma TAT and D-dimer were higher in the high grade SCE group than in the lower SCE group. Plasma TM was lower in the high grade SCE group. From these results, high grade SCE detected by TEE correlates with activation of coagulation and fibrinolysis.
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