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Publications and source records attributed to Y Teranishi.
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Optimal laser control for ultrafast selection of closely lying excited states whose energy separation is smaller than the laser bandwidth is reported on the two-photon transition of atomic cesium; Cs(6S-->7D(J), J=5/2 and 3/2). Selective excitation was carried out by pulse shaping of ultrashort laser pulses which were adaptively modulated in a closed-loop learning system handling eight parameters representing the electric field. Two-color fluorescence from the respective excited states was monitored to measure the selectivity. The fitness used in the learning algorithm was evaluated from the ratio of the fluorescence yields. After fifty generations, a pair of nearly transform-limited pulses were obtained as an optimal pulse shape, proving the effectiveness of the "Ramsey fringes" mechanism. The contrast of the selection ratio was improved by approximately 30% from the simple "Ramsey fringes" experiment.
The upstream region of the isocitrate lyase gene (UPR-ICL) from the n-alkane-utilizing yeast Candida tropicalis serves as a useful promoter of gene expression in the yeast Saccharomyces cerevisiae. The production of rat metabotropic glutamate receptor 1alpha (mGluR1alpha), which belongs to the G-protein-coupled receptor (GPCR) family, was tested under the control of UPR-ICL. Expression of mGluR1alpha was found in recombinant clones and enhanced by replacing the signal sequence of mGluR1alpha with the corresponding region of the alpha-factor receptor (Ste2), which is a GPCR found in S. cerevisiae. Moreover, the membrane fraction from a recombinant clone associated with Vesl-1S/Homer-1a protein binds the mGluR1alpha in rat cerebellum. These results suggest that the UPR-ICL-controlled gene expression system is useful for heterologous GPCRs in S. cerevisiae.
To determine whether angiotensin type 2 (AT(2)) receptor stimulation induces apoptosis in cardiomyocytes in vivo, we developed transgenic mice overexpressing the AT(2) receptor in a cardiac-specific manner, using the alpha-myosin heavy-chain promoter. Ten- to 12-week-old male homozygous transgenic mice (n=44) and wild-type mice (n=44) were used. Both transgenic and wild-type mice were given either saline (control), a subpressor dose of angiotensin II (100 ng. kg(-1). min(-1)), a pressor dose of angiotensin II (1000 ng. kg(-1). min(-1)) for 14 days, a pressor dose of angiotensin II for 28 days to investigate the effects of stimulation on both angiotensin type 1 (AT(1)) and AT(2) receptors, the AT(1) antagonist L158809 alone, or a combination of angiotensin II (1000 ng. kg(-1). min(-1)) and L158809 for 14 days to investigate the effects of selective AT(2) receptor stimulation. Apoptosis was analyzed in paraffin-embedded ventricular sections by the terminal deoxynucleotidyl-transferase-mediated dUTP nick-end labeling (TUNEL) technique. In both transgenic and wild-type mice, administration of a subpressor dose of angiotensin II, L158809, or a combination of angiotensin II and L158809 did not significantly affect the tail-cuff blood pressure or heart-to-body weight ratio, whereas administration of a pressor dose of angiotensin II for 14 or 28 days significantly increased blood pressure and the heart-to-body weight ratio. However, there was no statistical difference between the effects of angiotensin II in transgenic and wild-type mice. The number of TUNEL-positive nuclei was approximately 0 to 10 per 100 000 cardiomyocytes, with no difference between transgenic and wild-type mice, regardless of saline infusion or any stimulation. In infarcted canine myocardial tissue sections for positive control, the number of TUNEL-positive nuclei was increased by 13.8 to 19.1 times compared with those in the noninfarcted myocardium. In conclusion, angiotensin II infusion for a period of 28 days failed to induce cardiomyocyte apoptosis regardless of the presence or absence of cardiac AT(2) receptor overexpression. It is unlikely that in mice the AT(2) receptor is a strong signal to induce cardiomyocyte apoptosis in vivo.
We investigated whether a compensatory vasoconstrictor action would be induced by a hypotensive intervention in the hindquarter vascular region of conscious spontaneously hypertensive rats (SHRs). Mean arterial pressure and hindquarter blood flow were recorded. After hemorrhage (withdrawing blood, 0.3 ml/100 g body weight), hindquarter resistance (HQR) was increased significantly. The decrease in HQR induced by the administration of a ganglionic blocker (C6; 25 mg/kg, i.v.) was significantly greater in SHRs with hemorrhage than in those without hemorrhage. The present results suggest that a detectable hindquarter compensator tone occurs due to hemorrhage in SHRs, although an abnormal substantial vasoconstrictor tone already exists in the hindquarters.
The aim of this study was to compare the vasoconstrictor effect of sodium pentobarbital on the hindquarter resistance of intact control Wistar rats with the effect on lumbar-sympathectomized rats. For this purpose, mean arterial pressure (MAP) and hindquarter (supplied terminal aorta) flow (HQF) were simultaneously measured in these conscious rats with an arterial in dwelling cannula and electromagnetic flow probe implanted around the terminal aorta. Hindquarter resistance (HQR) was calculated as MAP divided by HQF. In the intact control conscious rats, subsequent pentobarbital anesthesia (30 mg/kg, i.v.) caused an increase in HQR (+43.5 +/- 7.4%, mean +/- S.E.M.) and a decrease in MAP (-17.0 +/- 3.2%). After pentobarbital anesthesia, subsequent ganglionic blockade with hexamethonium bromide (C6; 25 mg, i.v.) induced a significant decrease in HQR (-30.9 +/- 3.0%) with a further lowering of MAP (-20.9 +/- 1.6%). However, in rats not anesthetized with sodium pentobarbital, C6 alone induced almost no change in HQR (-3.4 +/- 5.3%), even when MAP was lowered (-24.2 +/- 2.5%). In the lumbar-sympathectomized rats, pentobarbital anesthesia produced almost no change in HQR (-11.7 +/- 4.4%), although MAP decreased significantly (-24.3 +/- 2.2%). These findings suggest that: (1) sodium pentobarbital anesthesia newly generates a compensatory vasoconstrictor tone in the hindquarters acting against the depressor effect, and (2) the vasocompensator tone is controlled by the efferent fibers, including those in the lumbar sympathetic nerves.
This study was conducted to examine the lymph node metastasis-related carbohydrate epitopes of cancer cells in primary lesions of gastric cancer with submucosal invasion (sm gastric cancer). A total of 118 formalin-fixed and paraffin-embedded surgical specimens were studied. Carbohydrate epitopes were detected histochemically using 17 kinds of biotin-labeled lectins and three kinds of monoclonal antibodies (mAbs) against Thomsen-Friedenreich antigen (HB-T1), Tn (HB-Tn1), and sialyl Tn antigens (HB-STn1). The node-positive group showed significantly lower reactivities with Ricinus communis I (RCA-I), Lotus tetragonolobus (Lotus), Triticum vulgaris (WGA), and Concanavalia ensiformis (ConA), and higher reactivities with HB-STn1. When sm gastric cancer was classified into differentiated and undifferentiated types, lower reactivities with RCA-I and ConA were observed in the differentiated type cancers, whereas lower reactivities with Lotus, WGA, and higher reactivity with HB-STn1 were observed in the undifferentiated type cancers. Nodal status was able to be predicted with high precision by a combination of these carbohydrates and histological subtypes. Since neuraminidase treatment rarely changed the reactivity of cancer cells with these lectins, we conclude that the loss of certain kinds of carbohydrates that are restricted by histological subtypes is related to lymph node metastasis in sm gastric cancer.
The cellular localization of the AT(2) receptor and the regulation of its expression in hypertrophied left ventricle are not well known. We compared the expression of the cardiac AT(1) and AT(2) receptor in spontaneously hypertensive rats/Izumo strain (SHR/Izm) and Wistar Kyoto rats/Izumo strain (WKY/Izm), ages 4, 12, and 20 wk, by means of immunohistochemistry and Western blot analysis. In SHR/Izm, compared with WKY/Izm, blood pressure (161 +/- 2 vs. 120 +/- 2 mmHg at 12 wk, P </= 0.01, and 199 +/- 3 vs. 123 +/- 3 mmHg at 20 wk, P </= 0.01) and heart-to-body weight ratio (3.76 +/- 0.07 vs. 3.06 +/- 0.06 mg/g at 12 wk, P </= 0.01, and 3.90 +/- 0.08 vs. 3.01 +/- 0.12 mg/g at 20 wk, P </= 0.01) were significantly elevated. There was no difference in these values between the two strains at 4 wk of age. Histologically, 20-wk-old SHR/Izm demonstrated myocardial hypertrophy, a thickening of the smooth muscle layer of the intracardiac arteries, and perivascular fibrosis. By immunohistochemistry, the AT(2) receptor was localized to cardiomyocytes and vascular endothelial cells, but not in the vascular smooth muscle cells. No major AT(2) receptor signal was observed in perivascular fibrosis at any age in either strain of rats. No difference was detected in this localization between the two strains. By Western blotting, a single 44-kDa band for the AT(2) receptor and a single 60-kDa band for the AT(1) receptor were detected in ventricles from both strains of rats at all ages. Densitometric analysis demonstrated that the AT(2) receptor 44-kDa band was decreased by 20% at 12 wk and 32% at 20 wk (P < 0.01) in SHR/Izm compared with WKY/Izm. The intensity of the AT(1) receptor 60-kDa band was increased by 57% in 20-wk-old SHR/Izm compared with WKY/Izm (P < 0.05). There was no significant difference in the intensity of the 44- or 60-kDa bands in 4-wk-old animals of either strain. We demonstrated a decrease in the AT(2) receptor and an increase in the AT(1) receptor protein with no change in their localizations in hypertrophied left ventricular myocytes of SHR/Izm.
One of two Ca antagonists, benidipine (3-30 microg/kg) or nifedipine (30-600 g/kg), was administered in a bolus injection through the jugular vein, and the changes in mean arterial pressure (MAP), renal flow (RF), and hindquarter flow (HQF) in conscious spontaneously hypertensive rats (SHRs) and normotensive control rats (NCRs). Renal vascular resistance (RR) and hindquarter resistance (HQR) were calculated as MAP divided by RF and HQF, respectively. When a high dose was administered to decrease the blood pressure by about 20%, the RR was significantly lower with benidipine than with nifedipine. The decrease in HQR was not significantly different between benidipine and nifedipine. When a low dose was administered to decrease the blood pressure by about 7%, the decrease in RR was not significantly different between benidipine and nifedipine, but the HQR was significantly lower with benidipine than with nifedipine. In the NCRs, no pharmacological properties were significantly different between these two Ca antagonists.
The interaction between [Arg8]-vasopressin and a vasopressin receptor antagonist, [d(CH2)5(1), O-Me-Tyr2, Arg8]-vasopressin, was examined in Hiroshima rats and normotensive control rats under pentobarbital anesthesia. [Arg8]-vasopressin dose-dependently increased the arterial pressure in both the Hiroshima and control rats, the pressor effect being greater in the Hiroshima rats. After the administration of a vasopressin antagonist (0.01 mg/kg), which by itself decreased arterial pressure only in the Hiroshima rats, the dose-response curve for [Arg8]-vasopressin was much more greatly shifted to the right in the control rats. These results indicate that with or without a vasopressin antagonist, the exogenous [Arg8]-vasopressin induced more powerful pressor actions in the Hiroshima rats compared to the control rats.
It has been suggested that some mitochondrial genes are important in cellular senescence. In order to identify the mitochondrial genes that are involved in cellular senescence, we have constructed a cDNA library from senescent human vascular endothelial cells and isolated 86 senescence-specific cDNA clones by differential screening. Among the clones, we identified four distinct mitochondrial genes including NADH dehydrogenase subunit 2 (ND2), ND3, ATPase 6 and 16S ribosomal RNA. We then compared the levels of expression of these genes in young and senescent cells by using two endothelial and two fibroblast cell strains. Northern blot and slot blot hybridization confirmed that the expression levels of ND3, ATPase 6 and 16S rRNA were elevated in senescent cells of all four strains. The expression level of ND2 was also elevated during cellular senescence in three of the four strains. Because mitochondria are actively involved in oxidative phosphorylation and respiratory functions, the altered expression levels of these genes may participate in aging processes.
The facial vein in several species has been shown to have unusual properties, including exhibition of spontaneous myogenic tone and relaxation to norepinephrine (NE). The present study was undertaken to characterize the relaxant effect of 5-hydroxytryptamine (5-HT) on the rabbit facial vein. An isolated ring preparation of the rabbit facial vein exhibited intrinsic tone when it was stretched and the spontaneous contraction continued for hours. 5-HT concentration-dependently relaxed facial veins exhibiting spontaneous contraction. The relaxation was not inhibited by rubbing the endothelium or by NG-nitro-L-arginine (10(-4) M), a nitric oxide (NO) synthase inhibitor. The 5-HT-induced relaxation was also unaffected by pretreatment with indomethacin (10(-5) M), a cyclooxygenase inhibitor, and propranolol (10(-6) M), a both beta-adrenoceptor and 5-HT18-receptor antagonist. In contrast, 5-HT-induced relaxation of the facial vein was concentration-dependently antagonized by methysergide (10(-7) M and 10(-6) M), a non-selective 5-HT1- and 5-HT2-receptor antagonist, but not by NAN-190 (10(-6) M) and SDZ-205,557 (10(-6) M), antagonists for 5-HT1A- and 5-HT4-receptors, respectively. A higher (10(-6) M), but not lower (3 x 10(-7) M) concentration of ketanserin, a 5-HT2-receptor antagonist, slightly inhibited the 5-HT-induced relaxation. These results indicate that 5-HT-induced relaxation is not due to indirect mechanisms mediated by NE released from the sympathetic nerve terminals, or by endogenous prostanoid and endothelium-derived relaxing factor (EDRF = NO) released from the vascular tissues, but due to a direct effect on the 5-HT receptors located on vascular smooth muscle cells. However, the subtype of 5-HT receptor that produces relaxation of the rabbit facial vein remains to be clarified.
The unidentified cell-surface antigen recognized by monoclonal antibody M7412 is distributed along motoneuron axonal outgrowth pathways in chicken embryos. To better characterize its role in motoneuron development, the M7412 antigen was purified from chicken embryos by immunoaffinity chromatography. Its N-terminal amino acid sequence corresponded to that predicted for chicken low-affinity nerve growth factor receptor (LNGFR). Experiments were performed to confirm that LNGFR was indeed the antigen recognized by M7412. First, M7412 bound to recombinant chicken LNGFR expressed in mammalian cells. Second, a rabbit serum raised to the purified antigen showed the same staining pattern in chicken embryos as did M7412. Lastly, a novel method for direct detection of nerve growth factor (NGF) bound to its receptors was used to show that in mixed spinal cord cultures, only neurons that expressed M7412 antigen had low-affinity binding sites for NGF. Furthermore, at the subcellular level, M7412 labeling was co-localized with bound NGF. The M7412 antigen is thus chicken LNGFR, whose role in motoneuron outgrowth pathways is discussed.
A truncated fragment of the cycloinulo-oligosaccharide fructanotransferase (CFTase) gene of Bacillus circulans MCI-2554 was fused to the prepro secretion sequence of the alpha-factor and expressed in Saccharomyces cerevisiae under the control of the 5' upstream region of the isocitrate lyase gene of Candida tropicalis (UPR-ICL). Efficiently secreted recombinant CFTase protein (yeast CFTase) was purified. Yeast CFTase consisted of three protein molecules, each of which had CFTase activity (yeast CFTase 1 [116 kDa], yeast CFTase 2 [117 kDa], and yeast CFTase 3 [116 kDa]). Yeast CFTase 2 was the major product of the expression system employed and was shown to be N glycosylated by endoglycosidase H treatment. Yeast CFTase 1 was N glycosylated but had a short truncation at its N terminus, while yeast CFTase 3 did not contain an N-glycosylated carbohydrate chain(s). Yeast CFTase 2 showed an optimum pH, an optimum temperature, and a pH stability similar to those of CFTase purified from B. circulans but exhibited a significant increase in thermostability. Production of yeast CFTase by the strain which had two copies of the CFTase gene integrated into its chromosomes reached 391 U per liter of culture at 120 h, which corresponded to 8.40 mg of protein per liter, by shake-flask cultivation.
We have designated the hindquarter (or terminal aortic) vascular resistance (HQR) of the rat as hindquarter compensator (HC) because it increases after such hypotensive interventions as pentobarbital anesthesia and nitrate administration, presumably due to reflex excitation of regional vasoconstrictor fibers. The aim of the present study was to observe whether the HC mechanism is also mobilized in response to hemorrhage. Rats were implanted with a 1.5 or 2 mm diameter electromagnetic flow probe at the terminal aorta for measurement of hindquarter flow (HQF). An indwelling catheter was placed in the right common carotid artery to measure arterial pressure (AP) and withdraw blood. Experiments were performed in conscious rats two or three days after implantation. HQR was calculated by dividing AP by HQF. About 10 min after withdrawing blood (0.3 ml/100 g body weight), ganglionic blockade with hexamethonium bromide significantly decreased HQR, which indicated a mobilization of the HC mechanism, a change not observed with superior mesenteric resistance. A quantitatively similar change was observed in HQR after withdrawing double the amount of blood, i.e., 0.6 ml/100 g body weight, suggesting that the HC mechanism is activated almost fully by the relatively small amount of blood loss of 0.3 ml/100 g body weight.
We have found that the upstream region of the isocitrate lyase gene (UPR-ICL) from the n-alkane-utilizing yeast Candida tropicalis was functional in Saccharomyces cerevisiae as a novel promoter with nonfermentable carbon sources, such as oleic acid, acetate, ethanol, and glycerol/lactate. The expression of two foreign genes coding for beta-galactosidase from Escherichia coli (LacZ) and glutamate decarboxylase from rat brain was carried out under the control of UPR-ICL. Expression of LacZ was repressed by glucose and enhanced over 300-fold by acetate. When an expression vector pWI3 containing multicloning sites between UPR-ICL and the transcriptional terminator of the isocitrate lyase gene (TERM-ICL) was used, the smaller isoform of glutamate decarboxylase (GAD65) was highly produced in a soluble and active form. These results demonstrate that the novel expression system using UPR-ICL and TERM-ICL from C. tropicalis is useful for the production of heterologous proteins in S. cerevisiae.
The upstream region of the isocitrate lyase gene (UPR-ICL, 1530bp) of an n-alkane-utilizable yeast, Candida tropicalis, induced gene expression in another yeast, Saccharomyces cerevisiae, when the yeasts were grown on acetate. Surprisingly, UPR-ICL displayed the same regulatory function in the bacterium Escherichia coli when grown on acetate. We determined the interesting nucleotide sequence of UPR-ICL. The deletion analysis of UPR-ICL in both cells revealed the presence of two distinct promoters: one was localized at -394 to -379 and regulated gene expression in S. cerevisiae; the other was located near the initiation codon and regulated gene expression in E. coli. The two promoter sequences were similar, but not identical to regulatory elements that have been previously reported in S. cerevisiae and E. coli, respectively. Accordingly, the possibility of novel regulatory mechanisms could not be excluded. This is an interesting example of the presence of distinct cis-acting regulatory elements responsible for the induction of gene expression in one gene by acetate in both S. cerevisiae and E. coli. Preservation of such promoters through evolution is also discussed.
To evaluate the contribution of peripheral blood monocytes (PBMC) to epidermotropic inflammatory reactions in psoriasis, using an enzyme-linked immunosorbent assay we measured spontaneous interleukin-8 (IL-8) production in PBMC obtained from patients with psoriasis. IL-8 production in the psoriatic PBMC was significantly higher than that in normal control PBMC. Plasma IL-8 levels in psoriatic patients were also moderately increased compared to normal control levels. IL-8 production in PBMC was closely related to the clinical severity of psoriasis and to the response to treatment, including systemic methotrexate (MTX) treatment and tonsillectomy. IL-8 production in PBMC was also positively related to the production of interleukin-1 beta (IL-1 beta), interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha) in these cells. We speculate that the chemotactic cytokine IL-8 contributes to the development of psoriatic skin lesions, and mediates inflammatory reactions from the inflammatory focus to the psoriatic lesions.