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Yoshikane H, Hidano H, Sakakibara A, Niwa Y, Goto H. Efficacy of a distal attachment in endoscopic resection of colorectal polyps situated behind semilunar folds. Endoscopy 2001; 33:440-2. [PMID: 11396764 DOI: 10.1055/s-2001-14261] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Abstract
BACKGROUND AND STUDY AIMS It is difficult, dangerous, and time consuming to resect colorectal polyps situated behind the semilunar folds. The aim of this study was to examine the efficacy of a distal attachment in the endoscopic resection of these polyps. PATIENTS AND METHODS The study group consisted of 11 patients, each with a colorectal polyp situated behind a semilunar fold, and of which the base was invisible without the use of a distal attachment. With the attachment fitted to the distal end of the endoscope, we pressed the semilunar fold situated at the anal side of the polyp so that the polyp, including its base, could be brought within the visual field. Maintaing the optimal position, we snared, ligated, and resected all polyps by electrocautery. RESULTS The polyps were of sessile type in eight patients and pendunculated type in three, with a diameter ranging from 7 to 18 mm (mean 11 mm). Although the base of the polyp was invisible under conventional observation, pressing the fold brought good visualization. The optimal position for snaring the polyp was secured by fine endoscopic adjustment, and the polyps were easily resected in all patients. CONCLUSION We conclude that the distal attachment is a simple but very valuable tool in the endoscopic resection of colorectal polyps situated behind the semilunar folds, and recommend its routine use in both diagnostic and therapeutic colonoscopy.
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102
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Mikawa K, Akamatsu H, Nishina K, Niwa Y. Effects of pirenzepine, omeprazole, lansoprazole, and rabeprazole on human neutrophil functions. Can J Anaesth 2001; 48:421-2. [PMID: 11339790 DOI: 10.1007/bf03014980] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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103
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Sakata T, Niwa Y, Goto H, Hirooka Y, Hayakawa T, Ohmiya N, Kobayashi S. Asymptomatic inflammatory bowel disease with special reference to ulcerative colitis in apparently healthy persons. Am J Gastroenterol 2001; 96:735-9. [PMID: 11280543 DOI: 10.1111/j.1572-0241.2001.03614.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
OBJECTIVE We examined cases of asymptomatic inflammatory bowel diseases, particularly asymptomatic ulcerative colitis, which were found in apparently healthy Japanese persons who underwent general health screening. METHODS Patients with positive immunological fecal occult blood test (IFOBT) among approximately 236,000 persons participating in the health screening program at the Aichi Prefectural Center for Health Care for the past 9 yr underwent total colonoscopy. In patients with ulcerative colitis, we investigated the sex and age distributions, extent of lesion, endoscopic activity, incidence rate, and clinical course. RESULTS In all, 35 cases of inflammatory bowel disease were detected, and 274 cases of colorectal cancer (not discussed here) were detected in the same population. The 35 cases of inflammatory bowel disease consisted of 19 cases of ulcerative colitis (12 of asymptomatic and minimally symptomatic ulcerative colitis, and seven of symptomatic or with past history of ulcerative colitis); five of intestinal tuberculosis; two of Crohn's disease; two of amebic colitis; and seven of endoscopic colitis. The 12 patients with asymptomatic and minimally symptomatic ulcerative colitis consisted of 11 men and one woman aged 36-63 yr (mean 46.2 yr). We classified these cases into three grades of severity according to endoscopic findings: four cases were mild, eight moderate, and none severe. Of these 12 cases, three were found endoscopically because of positive IFOBT, although barium enema was normal. Anatomic types of colitis cases included three of total colitis, three left-sided colitis, two proctitis, and four right-sided or segmental colitis. In one case, the disease extended proximally during the course of observation. CONCLUSIONS We found 35 cases of inflammatory bowel disease because of positive IFOBT performed as part of a general health screening. Of these, 19 cases were ulcerative colitis. These included many asymptomatic and minimally symptomatic cases, which could be very important in helping to elucidate the natural history of ulcerative colitis; thus, long-term follow up is necessary.
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Tomita G, Niwa Y, Shinohara H, Hayashi N, Yamamoto T, Kitazawa Y. Changes in optic nerve head blood flow and retrobular hemodynamics following calcium-channel blocker treatment of normal-tension glaucoma. Int Ophthalmol 2001; 23:3-10. [PMID: 11008892 DOI: 10.1023/a:1006423919238] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
BACKGROUND Because calcium channel blockers reduce vascular resistance, they may have a clinical application in the treatment of normal-tension glaucoma (NTG). This study investigates changes in both the optic disc blood flow and the hemodynamics of retrobulbar vessels in NTG patients after the systemic administration of a calcium channel blocker. METHODS Twelve eyes of 12 NTG patients (mean age 57.6 +/- 15.3 years) were examined before and after a 4-week treatment with 2 mg b.i.d. oral nilvadipine, an L-typc calcium channel blocker. By scanning laser-Doppler flowmetry (SLDF), we obtained the velocity, flow, and volume from within a 10 x 10 pixel window placed on the temporal rim region of the optic disc perfusion map. By ultrasound color Doppler imaging (CDI), we measured the peak systolic velocity (PSV) and the end diastolic velocity (EDV) of the ophthalmic artery (OA), central retinal artery (CRA), nasal posterior ciliary artery (NPCA), and temporal posterior ciliary artery (TPCA). We then calculated a resistance index (RI) for each vessel. RESULTS After treatment, the flow and velocity of the optic disc blood flow significantly increased (P < 0.05). Nilvadipine also significantly reduced RIs of the CRA, NPCA, and TPCA (P < 0.05), and increased both the PSV of the NPCA and the EDVs of the CRA, NPCA, and TPCA. The percent change in velocity correlated significantly with the percent changes of the CRA RI and NPCA RI. CONCLUSIONS Oral nilvadipine appears to reduce orbital vascular resistance, which consequently increases the optic disc blood flow.
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105
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Niwa Y, Akamatsu H, Niwa H, Sumi H, Ozaki Y, Abe A. Correlation of tissue and plasma RANTES levels with disease course in patients with breast or cervical cancer. Clin Cancer Res 2001; 7:285-9. [PMID: 11234881] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
The beta-chemokine RANTES was measured in plasma in 43 patients with breast cancer and in 23 patients with cervical cancer, and the RANTES content in primary tumors, tumor metastatic to lymph nodes, and clinically normal skin or pelvic mucosa was measured. In addition, plasma levels were determined in all of the patients for the platelet-derived chemokine beta-thromboglobulin (beta-TG) and for IFN-gamma, interleukin (IL)-2, IL-4, IL-5, and IL-10, along with serum IgE levels and blood eosinophils. Plasma RANTES levels were found to be higher in order of stages IV, III, II, and I of each cancer except for stage I. A marked increase in plasma RANTES level (> 10,000 pg/ml) was found in 27% of patients with progressive malignancy but in none of those in clinical remission. The platelet RANTES content was correspondingly decreased in those patients with increased plasma RANTES levels. Beta-TG showed a pattern similar to RANTES both in plasma and platelets, but with much less dramatic differences between patients with different stages of disease. Other allergic parameters, IgE, eosinophils and plasma IFN-gamma, IL-2, -5, and -10, were not elevated in the cancer patients. The RANTES content was markedly elevated in the primary tumor and metastatic lesions (lymph node or skin) from all of the patients with breast or cervical cancer, irrespective of the plasma RANTES level. In addition, in patients with progressive breast or cervical cancer, but not in patients thought to be cured of these tumors, the RANTES content was markedly increased in clinically normal tissue taken from near the operative site several months postoperatively, as well as in intact skin or mucosa taken perioperatively near the excised tumor. This study suggests an as-yet-undefined but important role played by RANTES in carcinogenesis, as well as the possibility that a RANTES assay in tissue surrounding a tumor or postoperative tumor site may help predict prognosis in these patients.
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Sitthithaworn W, Kojima N, Viroonchatapan E, Suh DY, Iwanami N, Hayashi T, Noji M, Saito K, Niwa Y, Sankawa U. Geranylgeranyl diphosphate synthase from Scoparia dulcis and Croton sublyratus. Plastid localization and conversion to a farnesyl diphosphate synthase by mutagenesis. Chem Pharm Bull (Tokyo) 2001; 49:197-202. [PMID: 11217109 DOI: 10.1248/cpb.49.197] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
cDNAs encoding geranylgeranyl diphosphate synthase (GGPPS) of two diterpene-producing plants, Scoparia dulcis and Croton sublyratus, have been isolated using the homology-based polymerase chain reaction (PCR) method. Both clones contained highly conserved aspartate-rich motifs (DDXX(XX)D) and their N-terminal residues exhibited the characteristics of chloroplast targeting sequence. When expressed in Escherichia coli, both the full-length and truncated proteins in which the putative targeting sequence was deleted catalyzed the condensation of farnesyl diphosphate and isopentenyl diphosphate to produce geranylgeranyl diphosphate (GGPP). The structural factors determining the product length in plant GGPPSs were investigated by constructing S. dulcis GGPPS mutants on the basis of sequence comparison with the first aspartate-rich motif (FARM) of plant farnesyl diphosphate synthase. The result indicated that in plant GGPPSs small amino acids, Met and Ser, at the fourth and fifth positions before FARM and Pro and Cys insertion in FARM play essential roles in determination of product length. Further, when a chimeric gene comprised of the putative transit peptide of the S. dulcis GGPPS gene and a green fluorescent protein was introduced into Arabidopsis leaves by particle gun bombardment, the chimeric protein was localized in chloroplasts, indicating that the cloned S. dulcis GGPPS is a chloroplast protein.
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Fuse T, Niwa Y, Umezu M, Yamada K. Growth of occult arteriovenous malformation after cerebral hemorrhage demonstrated by serial magnetic resonance imaging--case report. Neurol Med Chir (Tokyo) 2001; 41:83-6. [PMID: 11255632 DOI: 10.2176/nmc.41.83] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A 19-year-old male presented with sudden onset of right hemiparesis caused by left cerebral hemorrhage. Cerebral angiography demonstrated no vascular abnormality, and the hematoma was removed surgically. At operation, no abnormal vascular lesion was found in the brain adjoining the hematoma. Two years later, magnetic resonance (MR) imaging demonstrated a few foci of flow voids adjacent to the hematoma cavity. Four years after the hemorrhage, MR imaging showed more extensive flow-void abnormalities that indicated growth of an occult arteriovenous malformation (AVM). Cerebral angiography indicated a definite AVM supplied mainly by branches of the middle cerebral artery. Total resection of this lesion was performed. The histological diagnosis was typical AVM. Immunohistochemistry with vascular endothelial growth factor showed staining in the walls of the abnormal vessels. Serial MR imaging is very useful for the diagnosis and management of occult AVMs.
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Odori T, Goto H, Arisawa T, Niwa Y, Ohmiya N, Hayakawa T. Clinical results and development of variable-stiffness video colonoscopes. Endoscopy 2001; 33:65-9. [PMID: 11204990 DOI: 10.1055/s-2001-11174] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Abstract
BACKGROUND AND STUDY AIMS This study was designed to assess the usefulness of variable-stiffness video colonoscopes, compared with conventional videoscopes. PATIENTS AND METHODS The first prototype XCF-QAY1 and the latter prototype XCF-Q240A1 used in this study can be varied to 4 levels of stiffness of tube insertion during examination. In 352 consecutive colonoscopic examinations performed using these and two conventional scopes, the following data were recorded: time for intubation to the cecum, frequency of changes in the patients' posture, frequency of abdominal pressure attempts, and pain score. The degree of stiffness of the insertion tube and the examiners' impressions score were recorded only in procedures where the variable-stiffness scopes were used. RESULTS There was no significant difference between colonoscopes in the pain score. Total colonoscopy rate was 97.4%. The frequency of usage of the varying stiffness control in the colon according to site was as follows: descending colon, 57.3%; transverse colon, 32.8%, sigmoid colon, 7.6%; and ascending colon, 2.3%. A significant difference in the mean time for intubation to the cecum between the XCF-Q240A1 and conventional scopes was observed. Moreover, there were significant differences in the frequency of abdominal pressure attempts and changes in the patient's posture between conventional scopes and the new scopes. CONCLUSIONS These results suggest that only one scope, the XCF-Q240A1, is needed for any colonic examination by any examiner.
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Hosoi T, Goto H, Arisawa T, Niwa Y, Okada N, Ohmiya N, Hayakawa T. Role of nitric oxide synthase inhibitor in experimental colitis induced by 2,4,6-trinitrobenzene sulphonic acid in rats. Clin Exp Pharmacol Physiol 2001; 28:9-12. [PMID: 11153546 DOI: 10.1046/j.1440-1681.2001.03388.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
1. The present study was designed to investigate the role of nitric oxide (NO) in modulating 2,4,6-trinitrobenzene sulphonic acid (TNBS)-induced colitis in rats. 2. Damage scores and NO synthase (NOS) activity were measured. 3. The damage scores and NOS activity reached a peak on the 4th day after administration of TNBS solution (day 0), thereafter gradually decreasing, and were significantly higher than in the group treated with saline throughout the experimental period. 4. Subsequently, we divided the stage of colitis into two groups, one from day 0 to day 3 after induction of colitis, and the other from day 4 onwards. We evaluated the effects of the NOS inhibitor N(G)-monomethyl-L-arginine (L-NMMA), on TNBS-hapten-induced colitis and colonic mucosal blood flow. Two different methods of L-NMMA administration, from day 0 to day 3, and from day 4 onwards, were undertaken. 5. The damage score in the early L-NMMA treatment group was significantly higher than in the group without L-NMMA on day 14. In contrast, the damage score in the late L-NMMA treatment group was not significantly different from the group without L-NMMA. Colonic mucosal blood flow in the early L-NMMA treatment group was not significantly different from that in the late L-NMMA treatment group. 6. These data suggest that NO is important for inhibiting inflammation during the early stages.
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110
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Li Z, Chen X, Niwa Y, Sakamoto S, Nakaya Y. Involvement of Ca2+ -activated K+ channels in ginsenosides-induced aortic relaxation in rats. J Cardiovasc Pharmacol 2001; 37:41-7. [PMID: 11152372 DOI: 10.1097/00005344-200101000-00005] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Ginsenosides (GS), an extract of Panax ginseng, have been reported to be effective in inducing vascular relaxation mediated by nitric oxide (NO) release. The present experiments were designed to determine whether this GS-induced vasorelaxation also involves Ca2+ -activated K+ (KCa) channels in vascular smooth muscle cells (VSMC) in addition to endothelium-derived NO. GS induced vasorelaxation in rat aortic rings, which had been precontracted with phenylephrine, in a concentration-dependent manner. This GS-induced relaxation was partially reversed by tetraethylammonium (TEA), an inhibitor of KCa channels; methylene blue (MB), an inhibitor of soluble guanylate cyclase; as well as Nomega-nitro-L-arginine (L-NNA), but not by glybenclamide. In cultured VSMC and endothelial cells, KCa channels were activated by GS. This action was abolished by TEA, but was not blocked by glybenclamide. In addition, the GS-induced activity of KCa channels was partially inhibited by MB or H-8. These results indicate that the activation of KCa channels involved, at least in part, the GS-induced vasorelaxation of rat aorta.
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MESH Headings
- Analgesics/pharmacology
- Animals
- Aorta/drug effects
- Aorta/physiology
- Arginine/pharmacology
- Calcium/metabolism
- Cells, Cultured
- Endothelium, Vascular/cytology
- Endothelium, Vascular/drug effects
- Endothelium, Vascular/physiology
- Enzyme Inhibitors/pharmacology
- Ginsenosides
- Male
- Methylene Blue/pharmacology
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/physiology
- Nitric Oxide/antagonists & inhibitors
- Nitric Oxide/metabolism
- Nitroarginine/pharmacology
- Potassium Channels/drug effects
- Potassium Channels/physiology
- Rats
- Rats, Wistar
- Saponins/pharmacology
- Tetraethylammonium/pharmacology
- Vasodilation/physiology
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111
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Fuse T, Niwa Y, Harada S. Local intraarterial fibrinolytic therapy for embolic stroke associated with vascular anomalies--two case reports. Neurol Med Chir (Tokyo) 2000; 40:641-4. [PMID: 11153196 DOI: 10.2176/nmc.40.641] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Two cases of embolic stroke associated with vascular anomalies were treated by intraarterial fibrinolytic therapy. A 78-year-old male had embolic stroke associated with fenestration of the middle cerebral artery (MCA). The embolus lodged in the terminal portion of the right internal carotid artery (ICA) and in the M2 portion of the right MCA. The fenestration was not detected before local fibrinolytic therapy, but was identified by postinterventional angiography. An 82-year-old female had a left-sided persistent primitive trigeminal artery (PPTA), and the embolus lodged in the terminal portion of the left ICA. Left internal carotid angiography also showed rich collateral circulation via the abundant leptomeningeal anastomosis. The PPTA involved the left ICA, so the anomalous anatomy had to be considered in performing local thrombolysis. However, the rich collateral circulation allowed recanalization of the occluded ICA without inducing bleeding. Dissolution of persistently adherent emboli must be performed with great care because of the possibility of such rare vascular anomalies.
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112
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Li Z, Niwa Y, Sakamoto S, Shono M, Chen X, Nakaya Y. Induction of inducible nitric oxide synthase by ginsenosides in cultured porcine endothelial cells. Life Sci 2000; 67:2983-9. [PMID: 11133010 DOI: 10.1016/s0024-3205(00)00880-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Mechanism of Nitric oxide (NO) production by ginsenosides was investigated in cultured porcine endothelial cells. Beta-nicotinamide adenine dinucleotide phosphate (beta-NADPH) staining showed that the NO production was significantly enhanced by the presence of 40 microg/ml ginsenosides with 10 microM L-arginine after 12 h incubation. NO production was suppressed by addition of 0.5 microM Nomega-Nitro-L-arginine (L-NNA), an inhibitor of NO synthases (NOSs), to the incubation medium. In addition, the immunoreactive signals of inducible NOS (iNOS) were appeared in endothelial cells after 12-h incubation of ginsenosides, whereas the signals were not observed in non-treated cells. Our findings suggest that ginsenosides can enhance NO production by induction of iNOS in addition to its direct effect on endothelial cells by increasing intracellular Ca2+ concentration.
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113
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Kondo Y, Niwa Y, Yamamoto T, Sawada A, Harris A, Kitazawa Y. Retrobulbar hemodynamics in normal-tension glaucoma with asymmetric visual field change and asymmetric ocular perfusion pressure. Am J Ophthalmol 2000; 130:454-60. [PMID: 11024417 DOI: 10.1016/s0002-9394(00)00521-3] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
PURPOSE To investigate retrobulbar hemodynamics by means of color Doppler imaging in normal-tension glaucoma with asymmetric visual field change and asymmetric ocular perfusion pressure. METHODS Forty-nine consecutive patients who met the enrollment criteria were enrolled in a prospective study. We measured intraocular pressure at 2-hour intervals for 24 hours and performed color Doppler imaging of the orbital arteries, 48-hour ambulatory blood pressure monitoring, and visual field testing. Color Doppler parameters were compared between subjects with higher ocular perfusion pressure in the eye that had a better mean deviation (concordant group) and worse mean deviation (discordant group). RESULTS In the eyes with the better mean deviation, the end-diastolic velocity of the ophthalmic artery was significantly slower in the discordant group (P=.0145), while in the eyes with the worse mean deviation, the peak systolic and end-diastolic velocities of the ophthalmic artery were significantly slower and the resistance index of the ophthalmic artery was significantly higher in the discordant group (P=.0395, P=.0088, and P=.0324, respectively). In the concordant group, the end-diastolic velocity of the central retinal artery was slower in eyes with a worse mean deviation. CONCLUSION Retrobulbar hemodynamics are significantly altered in patients with normal-tension glaucoma who have better ocular perfusion pressure in the eye that has a worse mean deviation.
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114
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Niwa Y, Nagata N, Oka M, Toyoshima T, Akiyoshi H, Wada T, Nakaya Y. Production of nitric oxide from endothelial cells by 31-amino-acid-length endothelin-1, a novel vasoconstrictive product by human chymase. Life Sci 2000; 67:1103-9. [PMID: 10954044 DOI: 10.1016/s0024-3205(00)00700-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Human chymase selectively converts big endothelin (ET)-1 to 31-amino-acid-length ET-1 [ET-1(1-31)]. In this study we examined effect of ET-1(1-31) on endothelial function. ET-1(1-31) evoked contraction in a concentration-dependent manner at > 10(-8) M, which was about 10 times weaker than that of conventional ET-1 [ET-1(1-21)]. BQ485, an ETA receptor antagonist, completely abolished ET-1(1-31)-induced contraction, but BQ788, an ETB receptor antagonist, slightly enhanced it, suggesting that ET-1(1-31) relaxes artery via endothelium. On endothelial cells, ET-1(1-21) and ET-1(1-31) increased [Ca2+]i and produced NO, both of which were significantly inhibited by BQ788 and not by BQ485. These results indicate that ET-1(1-31) increased [Ca2+]i and produced NO in endothelial cells through ETB receptor similarly with ET-1(1-21), although slight difference in effect on smooth muscle cells.
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115
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Nagata N, Niwa Y, Nakaya Y. A novel 31-amino-acid-length endothelin, ET-1(1-31), can act as a biologically active peptide for vascular smooth muscle cells. Biochem Biophys Res Commun 2000; 275:595-600. [PMID: 10964709 DOI: 10.1006/bbrc.2000.3292] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Human chymase produces a novel endothelin-1 with 31 amino-acid length ¿ET-1(1-31)¿, which is longer than conventional ET-1, ¿ET-1(1-21)¿. The aim of our study was to investigate the role of ET-1(1-31) on porcine coronary vascular smooth muscle cell (VSMC). Although the increase in [Ca(2+)](i) by ET-1(1-31) was 10 times weaker than that of ET-1(1-21), ET-1(1-31) showed equivalent potency in VSMC proliferation, c-fos/c-myc mRNA expression and cell cycle analysis with ET-1(1-21). ET-1(1-31) significantly induced expression of cyclin D1 but not those of cyclin D2 or D3. These effects were specifically inhibited by BQ485, an ET(A) receptor antagonist, although that of ET-1(1-21) was not specific to BQ485, suggesting different receptor specificity from ET-1(1-21). These results indicate that ET-1(1-31) also can involve a VSMC proliferation process such as atherosclerosis, although it has weaker vasoconstricting potency and different receptor subtypes on VSMC from those of ET-1(1-21).
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116
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Nakaya Y, Ohnaka M, Sakamoto S, Niwa Y, Okada K, Nomura M, Hara T, Kusonoki M. Respiratory quotient in patients with non-insulin-dependent diabetes mellitus treated with insulin and oral hypoglycemic agents. ANNALS OF NUTRITION & METABOLISM 2000; 42:333-40. [PMID: 9895421 DOI: 10.1159/000012753] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The respiratory quotient (RQ) reflects the amount of energy derived from carbohydrate as apposed to fat metabolism. To assess the metabolic state of patients with non-insulin-dependent diabetes mellitus, the RQ was measured five times a day (at 09.00, 11.00, 13. 00, 14.00, and 17.00 h) in 20 healthy subjects and 60 diabetic patients. Diabetic patients treated with insulin or sulfonylurea showed significantly higher RQ values than normal subjects and nontreated diabetic patients. Diabetic patients without treatment showed higher glucose levels, and their RQ values were significantly lower than those of treated patients. There was a significant inverse correlation between RQ and blood glucose levels at 11.00 h (r = -0.361, p < 0.01) in diabetic patients, but no significant relation with HbA1c. Treated diabetic patients with a higher body mass index tended to show a higher RQ than those with a lower one (r = -0.269, p = 0.083). Within 1 year, 7 of 13 patients, who had RQ > 1.0, gained more than 3 kg, while only 5 of the remaining 32 treated diabetic patients gained more than 3 kg (p < 0.05). This demonstrates that diabetic patients with a higher RQ tended to gain weight despite the use of insulin or oral hypoglycemia agents. The RQ increased by infusing both insulin and glucose in normal subjects. These results suggest that a high RQ results from excess insulin and excess food. The RQ is a good predictor of weight gain in diabetic patients treated with either insulin or oral hypoglycemic agents.
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117
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Ohnaka M, Iwamoto M, Sakamoto S, Niwa Y, Matoba H, Nakayasu K, Nakaya Y. Does prolonged exercise alter diet-induced thermogenesis? ANNALS OF NUTRITION & METABOLISM 2000; 42:311-8. [PMID: 9895418 DOI: 10.1159/000012750] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Diet-induced thermogenesis (DIT) is mainly an insulin-mediated response and the result of fat and glycogen synthesis. We investigated DIT at rest and after exercise to clarify the mechanism of exercise-induced changes in DIT in 6 healthy men (mean age 36 +/- 16 years). Subjects exercised for 1 h at 58% of maximal O2 consumption on a bicycle ergometer and then rested for 8 h sitting in a comfortable chair (exercise experiment). On a different day, subjects rested for 8 h without preceding exercising (non-exercise experiment). At 12.30 h, the subjects were given their second meal. DIT to individual meal did not differ significantly between the exercise and non-exercise days. Increased insulin sensitivity and increased free fatty acid oxidation by exercise may facilitate the conversion of glucose to glycogen in muscle. On the other hand, insulin secretion expressed as the ratio of plasma levels of insulin to glucose after the meal was significantly decreased in the exercise experiment (p < 0.05). Study of heart rate variability showed that sympathetic tone, a primary hormonal determinant of glucose metabolism during exercise, was increased and parasympathetic tone was decreased during the recovery period in the exercise experiment (p < 0.05). These findings suggest that changes in DIT are affected by many factors and may be related to the balance between these counteracting factors.
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118
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Niwa Y, Akamatsu H, Sumi H, Ozaki Y, Abe A. Evidence for degradation of cytokines in the serum of patients with atopic dermatitis by calcium-dependent protease. Arch Dermatol Res 2000; 292:391-6. [PMID: 10994773 DOI: 10.1007/s004030000148] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Changes in the levels of cytokines in the circulating blood and skin have been reported in patients with atopic dermatitis (AD). We determined IFN-gamma, IL-2, IL-4, IL-5 and IL-10 in both the serum and plasma of 45 AD patients and 20 healthy donors. Since differences in the levels of these cytokines between serum and plasma were found, the roles of Ca2+ and proteolytic enzymes were examined. Levels of IL-2 and IL-10 were measured in citrated plasma to which various amounts of CaCl2, protease inhibitors, and proteases had been added. All cytokine determinations were carried out using a standard ELISA. The plasma levels of IFN-gamma, IL-2, and IL-5 were significantly elevated, but the serum levels of these cytokines were not significantly changed. The levels of IL-2 in the plasma of the AD patients averaged 4.25-fold higher than in the serum of the AD patients, and 2.5-fold higher than in the plasma of healthy controls (P < 0.001). CaCl2 produced a dose-dependent decrease in IL-2 and IL-10 in citrated plasma. The protease inhibitors PMSF, aprotinin and leupeptin produced a dose-dependent increase in measurable levels of IL-2 and IL-10 in plasma. A decrease in IL-2 levels was also seen in CaCl2-supplemented serum-free medium, and this was accentuated by the addition of the proteases thrombin, trypsin, chymotrypsin and elastase. These findings suggest that although significant changes in cytokine levels have been reported not to occur in circulating blood but have been reported to occur in the skin of AD patients both in vivo and in vitro, cytokines can indeed also be found to be elevated in circulating blood when assessed carefully by statistically valid methods. Further, it is suggested that during the preparation of serum, some circulating cytokines are degraded by calcium-dependent proteases, and that Ca2+ itself can also affect the measurement of cytokines. The measurement of circulating cytokines needs to be carefully reassessed.
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Sakamoto S, Muto T, Yokota M, Ishimura N, Niwa Y, Harada N, Okada K, Nakaya Y. Comparison between short-term food restriction and exercise on whole body glucose disposal in high-fat rats. THE JOURNAL OF MEDICAL INVESTIGATION 2000; 47:138-44. [PMID: 11019493] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
High-fat diets induce whole-body insulin resistance. The aim of this study was to compare effect of two interventions: 3-day food restriction (66% of ad libitum fed) and 3-day exercise training (voluntary running wheels), on decreased insulin-mediated whole body glucose uptake in high-fat fed rats (5 mo old) using the hyperinsulinemic euglycemic clamp procedure. The control group was maintained on rat chow alone. After high-fat feeding for 2 wk, insulin-stimulated whole body glucose utilization was significantly decreased by 26%. The exercise training was more effective than food restriction in lowering plasma concentrations of insulin and triacylglycerol and tissue concentrations of triacylglycerol in soleus muscles. Diminished whole-body glucose uptake resulting from high-fat feeding was reversed completely by exercise training, but only partially by food restriction. The time course of starvation on insulin-stimulated glucose uptake was also observed in high-fat fed rats. Although the extension of starvation time to 48 h resulted in decreased plasma glucose, insulin and triacylglycerol concentrations, whole body glucose uptake did not increase further. These findings suggest that short-term exercise has a higher restorative effect on insulin sensitivity in high-fat fed rats than food restriction, in spite of the same loss in body weight, presumably due in part to improved local lipid availability.
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Shinkai M, Niwa Y, Arisawa T, Ohmiya N, Goto H, Hayakawa T. Evaluation of prognosis of squamous cell carcinoma of the oesophagus by endoscopic ultrasonography. Gut 2000; 47:120-5. [PMID: 10861273 PMCID: PMC1727960 DOI: 10.1136/gut.47.1.120] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
BACKGROUND/AIMS For pretherapeutic staging of squamous cell carcinoma of the oesophagus, endoscopic ultrasonography (EUS) is considered the most profitable modality because it can provide cross sectional imaging of the tumour. The aim of this study was to evaluate the relation between prognosis and EUS findings, especially tumour area, in squamous cell carcinoma of the oesophagus. PATIENTS/METHODS A total of 113 patients with squamous cell carcinoma of the oesophagus underwent EUS for pretherapeutic examination at Nagoya University Hospital. We compared EUS findings, histological results, and outcome. In addition, we measured the area of the tumour on EUS images (n=113) and evaluated if EUS area correlated with volume of the tumour on histological findings (n=50). RESULTS The overall accuracy rate of EUS was 83.2% (94/113) for depth of tumour invasion and 67.6% (69/102) for perioesophageal lymph node metastasis. The EUS area increased in proportion to the development of tumour infiltration, and patients with lymph node metastasis had a larger EUS area than patients without lymph node metastasis. There was a close correlation between EUS area and volume of the tumour on histological findings. If EUS area of the tumour was less than 50 mm(2), the five year survival rate was 100%. As EUS area increased, the survival rate decreased. CONCLUSIONS Measurement of EUS area of the tumour is reliable for quantification of the tumour and prediction of prognosis in patients with squamous cell carcinoma of the oesophagus.
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Fukuoka H, Ogawa T, Mitsuhara I, Iwai T, Isuzugawa K, Nishizawa Y, Gotoh Y, Nishizawa Y, Tagiri A, Ugaki M, Ohshima M, Yano H, Murai N, Niwa Y, Hibi T, Ohashi Y. Agrobacterium-mediated transformation of monocot and dicot plants using the NCR promoter derived from soybean chlorotic mottle virus. PLANT CELL REPORTS 2000; 19:815-820. [PMID: 30754875 DOI: 10.1007/s002990000191] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The NCR promoter (PNCR) from soybean chlorotic mottle virus (SoyCMV) was used to express the selectable marker, neomycin phosphotransferase (nptII) gene, in Agrobacterium-mediated transformation of both monocot (rice) and dicot (tobacco) plants. A multi-cloning site for insertion of a gene of interest into the binary vector pTN is located proximal to the right border region of T-DNA. When chimeric genes under the control of other strong promoters were located in a head-to-head orientation to the PNCR-nptII gene, kanamycin-resistant tobacco shoots were generated more efficiently than when using the original pTN vectors. This suggests that the enhancer-like sequences in the promoters adjacent to PNCR may promote expression of the PNCR-nptII gene.
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Yoshikane H, Hidano H, Sakakibara A, Niwa Y, Goto H. Feasibility study on endoscopic suture with the combination of a distal attachment and a rotatable clip for complications of endoscopic resection in the large intestine. Endoscopy 2000; 32:477-80. [PMID: 10863916 DOI: 10.1055/s-2000-648] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
BACKGROUND AND STUDY AIMS Endoscopic resection has been more frequently performed for increasingly larger intramucosal tumors of the large intestine in recent years. It is reasonable to expect that the larger the resected mucosal surface, the greater is the likelihood of complications such as bleeding or perforation. The aim of this study was to explore the feasibility of endoscopic suture with a distal attachment and a rotatable clip-fixing device for complications of endoscopic resection in the large intestine. PATIENTS AND METHODS The study population consisted of 15 patients who underwent endoscopic clipping therapy following endoscopic resection for intramucosal tumors of the large intestine. With a distal attachment fitted to the distal end of the endoscope, the optimal position for clipping was ensured by pressing the intestinal wall and deflating the intraluminal air little by little. With a rotatable clip-fixing device, the resection site was endoscopically sutured clip by clip. RESULTS Tumors were of the laterally spreading tumor type in six patients, small sessile polyps in three, and pedunculated polyps in six. The complications consisted of bleeding in 12 patients, overt perforation in one, and latent perforation in two; 14 of the 15 patients underwent successful suturing by this method. The number of clips used ranged from two to seven (mean 4.4). No patients had further complications after the treatment. CONCLUSION We conclude that endoscopic suture with the combination of a distal attachment and a rotatable clip-fixing device is very useful for complications of endoscopic resection in the large intestine.
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Niwa Y, Yamamoto T, Harris A, Kagemann L, Kawakami H, Kitazawa Y. Relationship between the effect of carbon dioxide inhalation or nilvadipine on orbital blood flow in normal-tension glaucoma. J Glaucoma 2000; 9:262-7. [PMID: 10877378 DOI: 10.1097/00061198-200006000-00010] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PURPOSE To investigate the relationship between the effect of carbon dioxide (CO2) inhalation or oral nilvadipine, a calcium-channel blocker, on orbital blood flow in patients with normal-tension glaucoma, as determined by color Doppler imaging. PATIENTS AND METHODS Sixteen patients with normal-tension glaucoma (mean age, 55.6+/-9.8 years; male:female ratio, 3:13) underwent color Doppler imaging to measure the resistance index, and peak systolic and end-diastolic blood flow velocities of the ophthalmic artery, central retinal artery, and nasal and temporal short posterior ciliary arteries. Measurements were taken before and during CO2 supplementation sufficient to increase the end-tidal CO2 partial pressure by 10%. The color Doppler imaging measurements were repeated after 2 to 4 weeks of treatment with 2 mg oral nilvadipine, and comparisons were made between the effects of the two treatments. RESULTS Both CO2 inhalation and nilvadipine treatment significantly reduced the resistance index in the central retinal artery, nasal short posterior ciliary artery, and temporal short posterior ciliary artery. There was a significant correlation between the effects of the two treatments on the difference in the resistance indexes of the ophthalmic artery and central retinal artery, but not on those of the nasal or temporal short posterior ciliary artery. CONCLUSIONS Both CO2 inhalation and oral nilvadipine significantly reduce the resistance index measured by color Doppler imaging in orbital vessels. The effect of oral nilvadipine might be predicted by CO2 inhalation in patients with normal-tension glaucoma.
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Tsukamura H, Thompson RC, Tsukahara S, Ohkura S, Maekawa F, Moriyama R, Niwa Y, Foster DL, Maeda K. Intracerebroventricular administration of melanin-concentrating hormone suppresses pulsatile luteinizing hormone release in the female rat. J Neuroendocrinol 2000; 12:529-34. [PMID: 10844581 DOI: 10.1046/j.1365-2826.2000.00482.x] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Melanin-concentrating hormone (MCH) has been reported to be involved in the regulation of feeding behaviour in rats and mice. Because many neuropeptides that influence ingestive behaviour also regulate reproductive function, the present study was designed to determine if central administration of MCH changes pulsatile secretion of luteinizing hormone (LH) in the rats. Wistar-Imamichi strain female rats were ovariectomized and implanted with oestradiol to produce a moderate inhibitory feedback effect on LH release. The effects of i. c.v. injections of MCH on LH release were examined in freely moving animals. Blood samples were collected every 6 min for 3 h through an indwelling cannula. After 1 h of sampling, MCH (0.1, 1 or 10 microg/animal) or vehicle (saline) was injected into the third cerebroventricle. Because MCH is also reported to affect the hypothalamo-pituitary-adrenal (HPA) axis, which in turn, can influence reproductive function, plasma corticosterone concentrations were determined in the same animals at 30-min intervals during the first and last hours and every 12 min during the second hour of the 3-h sampling period. When expressed as per cent changes, mean plasma LH concentrations after MCH administration were significantly lower in the animals injected with all doses of the peptide compared with vehicle-treated animals; LH pulse frequency was significantly lowered by 1 microg of MCH. Per cent changes in mean plasma corticosterone levels were not significantly affected by MCH administration. These results in oestradiol-treated ovariectomized rats indicate that central MCH is capable of inhibiting pulsatile LH secretion. We have previously shown that 48-h fasting suppresses pulsatile LH release in the presence of oestrogen. Take together, these results raise the possibility that MCH could play a role in mediating the suppression of LH secretion during periods of reduced nutrition.
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Kanai H, Niwa Y, Koide K. [Hypertensive putaminal hemorrhage with extensive subarachnoid hemorrhage presenting extravasation of contrast material during angiography: case report]. NO SHINKEI GEKA. NEUROLOGICAL SURGERY 2000; 28:465-9. [PMID: 10806632] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
The authors describe a case of hypertensive putaminal hemorrhage with extensive subarachnoid hemorrhage. On admission, the patient aged 71 presented right-sided motor weakness. CT scan on admission revealed left putaminal hemorrhage with extension into the ipsilateral thalamus and lateral ventricle as well as into the subarachnoid space of the suprasellar, ambient, interhemispheric and contralateral sylvian cisterns. To exclude vascular lesions, left carotid angiography was performed just after admission. The lateral view was unremarkable, but the anterior-posterior view demonstrated extravasation of contrast material from the left lateral lenticulostriate artery. The angiographic sylvian point was shifted to the lateral side. No abnormal vessels were revealed. CT scan after angiography showed exacerbation of both intracerebral and subarachnoid hemorrhages, but the consciousness level was unchanged. CT-guided stereotactic aspiration of the hematoma was performed 4 days after the onset, but failed to remove much hemtoma. The patient died of aspiration pneumonia 9 days after onset. The authors emphasize that extensive subarachnoid hemorrhage in cases with hypertensive putaminal hemorrhage may be an important finding which indicates high risk of rebleeding.
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