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101.
Yoshie Sugiura Andreas Woppmann George P. Miljanich Chien -Ping Ko 《Journal of neurocytology》1995,24(1):15-27
Summary Voltage-sensitive Ca2+ channels are essential to transmitter release at the chemical synapse. To demonstrate the localization of voltage-sensitive Ca2+ channels in relation to the site of transmitter release, mouse neuromuscular junctions were double-labelled with -bungarotoxin and a novel voltage-sensitive Ca2+ channel probe, SNX-260, a synthetic analog of -conopeptide MVIIC. Similar to -conopeptide MVIIC, biotinylated SNX-260 blocked nerve-stimulated transmitter release at the mouse neuromuscular junction. Fluorescently-tagged biotinylated SNX-260 labelled the nerve terminal which appeared thinner than and was outlined by acetylcholine receptor clusters as seen inen face view. This SNX-260 labelling was inhibited by preincubation with unconjugated SNX-260. Side-views of the neuromuscular junction indicated that the SNX-260 labelling was on the synaptic side facing the acetylcholine receptor rather than on the nonsynaptic side of the nerve terminal. This presynaptic binding was confirmed by the absence of SNX-260 labelling in denervated muscles following a nerve cut or disjunction after collagenase treatment. Confocal microscopy revealed spots of SNX-260 labelling that may correlate with active zones. The SNX-260 labelling pattern was not affected by preincubation with unconjugated SNX-111 (-conopeptide MVIIA), an N-type voltage-sensitive Ca2+ channel blocker. These findings suggest that SNX-260 is a novel probe for localizing non-N type voltage-sensitive Ca2+ channels and that these voltage-sensitive Ca2+ channels are localized near the transmitter release sites at the mammalian motor nerve terminal membrane. The results are consistent with the suggestion that non-N, probably P/Q type voltage-sensitive Ca2+ channels mediate evoked transmitter release at the mammalian neuromuscular junction. 相似文献
102.
PCNA immunostaining combined with AgNOR staining in esophageal squamous cell carcinoma to identify patients with a poor prognosis 总被引:6,自引:0,他引:6
Yoshihisa Morisaki Shingo Shima Yutaka Yoshizumi Yoshiaki Sugiura Susumu Tanaka Seiichi Tamai 《Surgery today》1995,25(5):389-395
Immunostaining of the proliferating cell nuclear antigen (PCNA) provides important information about cell kinetics and is easily performed on routinely obtained formalin-fixed, paraffin-embedded materials. We report herein the results of a retrospective study on PCNA staining in esophageal cancer undertaken to determine its significance. As this study indicated that immunoreactivity was preserved in specimens fixed within 24 h, only 31 specimens from surgical patients were available for this investigation. The mean PCNA index of the patients without invasion to the adventitia (35.7±17.9) was significantly lower than that of those with invasion to the adventitia or neighboring structures (49.7±14.5), while the PCNA index did not correlate with other clinicopathologic parameters such as histologic type, lymph node metastases, or prognosis. However, when an analysis of PCNA staining was combined with an analysis of argyrophilic nucleolar organizer region (AgNOR) staining, a correlation with prognosis was found. In fact, seven patients with a high PCNA index (44) and AgNOR count (6) had a significantly poorer prognosis than the remaining 22 (P=0.0014), and six of these seven patients died within 2 years. These results indicate that this combined evaluation may be useful for the identification of patients with a poor prognosis among those undergoing surgery for esophageal squamous cell carcinoma. 相似文献
103.
An 18-year-old Japanese boy and a 10-year-old Chinese boy both had nearly complete cutaneous syndactyly of the fingers and toes, six diphalangeal fingers on each hand, six toes on each foot (except the right foot of patient 2), and short, deformed, and on occasion partially fused metacarpals and metatarsals. Neither had other malformations and were of normal intelligence. The accessory toes in patient 1 were mesoaxial, each situated between the hallux and the third toe, whereas those in patient 2 were postaxial. In view of these findings, the disorder in 2 individuals is likely to represent a hitherto undescribed type of nonsyndromic synpolydactyly. 相似文献
104.
Early detection of the no-reflow phenomenon in reperfused acute myocardial infarction using technetium-99m tetrofosmin imaging 总被引:1,自引:0,他引:1
Hamada S Nakamura S Sugiura T Murakami T Fujimoto T Watanabe J Baden M Hatada K Iwasaka T 《European journal of nuclear medicine》1999,26(3):208-214
Evaluation of myocardial perfusion in the early stage of acute myocardial infarction (MI) is clinically important for adjunctive therapies to minimize infarct size. To determine the role of early scintigraphic detection of impaired myocardial reperfusion after primary coronary angioplasty (PTCA) in patients with acute MI, semiquantitative technetium-99m tetrofosmin single-photon emission tomographic (SPET) imaging was performed before primary PTCA (before; area at risk), 60 min after PTCA (after) and at 1 month (1 M; final infarct) in 35 patients with acute MI. The left ventricle was divided into 13 segments and the defect score was calculated as the sum of the perfusion defect of each segment, from 3 (complete defect) to 0 (normal perfusion). A significant myocardial perfusion change after PTCA was defined as a change in the defect score (before minus after PTCA) of >/=4. The echocardiographic asynergic score was defined as the number of asynergic (severe hypokinetic or akinetic) segments corresponding to the analogous segments on SPET images, and recovery of wall motion was calculated as absolute change in the asynergic score (before PTCA minus 1 M). Among the 35 patients, 15 (43%) had a change in the defect score of <4 (no reflow: group 1) while 20 had a change in the defect score of >/=4 (reflow: group 2). There were no significant differences between the two groups with respect to the time between admission to PTCA, revascularization time, collateral grade or Thrombolysis in Myocardial Infarction (TIMI) flow grade before PTCA. Despite the lack of a difference in area at risk between the two groups (group 1 = 12.8+/-4.3 and group 2 = 15.1+/-4.7), final infarct size in group 1 was significantly larger compared with that in group 2 (8.1+/-4.3 vs 4.9+/-3.0, P<0.001). Recovery of wall motion was significantly smaller in group 1 than in group 2 (4.3+/-1.7 to 3.5+/-1.5 vs 4. 1+/-2.1 to 1.6+/-1.6, P<0.001). In conclusion, a small change (<4) in defect score (scintigraphic no-reflow phenomenon) after primary PTCA indicates persisting impaired myocardial perfusion or irreversible cellular damage just after PTCA which is associated with poor recovery of wall motion, as compared with that observed in cases of reflow (>/=4 in defect score). 相似文献
105.
Sato N Nakamura K Nakamura A Sugiura M Ito K Fukuda H Kawashima R 《Neuroreport》1999,10(17):3633-3637
Using magnetoencephalography (MEG), the neural response to scenes was recorded and compared with that to faces. The prominent MEG signals in response to scenes appeared 200-300 ms after the stimulus presentation while those in response to faces appeared between 150 and 200 ms. Source locations of the signals were estimated in the right parahippocampal and parieto-occipital regions with a latency of 300 ms for the scene response, whereas those were estimated in the lingual or fusiform gyri bilaterally with a latency of 160 ms for the face response. These data suggest that both the temporal and parietal regions process scenes, while the occipito-temporal regions process faces, and that scene processing takes a longer time than face processing. 相似文献
106.
Sugiura Y Hiramatsu H Miyamoto T Takehara S Akamine S Sumiya K Shinohara Y Ohishi H Hinokuma K 《No shinkei geka. Neurological surgery》1999,27(2):147-154
Endovascular treatment of intracranial aneurysms using plantinum coils was performed in 10 patients over 80 years of age. The patients ranged in age from 81 to 96 years. Preoperative Hunt and Kosnik grading revealed one patient in grade I, 4 in grade II, 3 in grade III, and 2 in grade IV. The aneurysms were located in the internal carotid artery in 6 patients, in the anterior communicating artery in 1, and in the middle cerebral artery in 3 respectively. Intra-aneurysmal occlusion was accomplished in 8 patients with total or subtotal occlusion in 6 and partial occlusion in 2. In one patient with a peripheral middle cerebral artery aneurysm, the parent artery was occluded just proximal to the aneurysm. In the remaining one patient in grade III, an aneurysm associated with wide neck could not be occluded because of coil protrusion into the parent artery. In 9 patients who were successfully treated, all five patients in grade I or II and one in grade III resulted in good outcome, but the other three patients in grade III and IV showed poor outcome. No evidence of recurrent hemorrhage was noted during the follow-up period ranging from 2 months to 4 years. Endovascular coil embolization is a useful therapeutic alternative for treating ruptured intracranial aneurysms in patients over 80 years of age, especially those in Grade I or II. 相似文献
107.
PURPOSE: The role of Epstein-Barr virus (EBV) reactivation in the pathogenesis of Vogt-Koyanagi-Harada (VKH) disease was examined. MATERIAL AND METHODS: Using B lymphocytes obtained from 8 patients with VKH disease and 10 patients with other types of uveitis, immortarized lymphoblast lines were established and infected with EBV. The degree of EBV activation in each lymphoblast line, in the presence and absence of various stimuli, was assessed by measuring the expression of 3 different antigens involved in replication by immunofluorescent staining and western blot analysis. Quantification of EBV DNA in cell culture supernatants was done by polymerase chain reaction. RESULT: Cell lines established from VKH patients expressed more viral antigens that those established from patients with other types of uveitis. There were greater amounts of EBV DNA in the VKH cell lines. CONCLUSION: B lymphocytes from VKH patients may be more susceptible to EBV activation, and the reactivation of EBV may be involved in the pathogenesis of VKH. 相似文献
108.
Long-term administration of atrial natriuretic peptide in patients with acute heart failure. 总被引:4,自引:0,他引:4
S Kitashiro T Sugiura Y Takayama Y Tsuka T Izuoka S Tokunaga T Iwasaka 《Journal of cardiovascular pharmacology》1999,33(6):948-952
A short-term treatment of atrial natriuretic peptide (ANP), a circulating hormone of cardiac origin, is reported to improve cardiac performance in patients with chronic heart failure. However, clinical usefulness of long-term administration of ANP in patients with congestive heart failure has not been reported. We studied 36 patients with severe acute heart failure who resisted various therapy. Hemodynamic parameters were measured before and 48 h after initiating ANP infusion (n = 18) or normal saline (n = 18). Mean pulmonary capillary wedge pressure (23-->13 mm Hg), mean right atrial pressure (10-->5 mm Hg), systemic vascular resistance (2,169-->1,307 dyn x s x cm(-5)) and pulmonary vascular resistance (318-->136 dyn x s x cm(-5)) decreased significantly, whereas cardiac index (1.9-->2.6 L/min/m2) and urine volume (1,692-->2,560 ml/day) increased during long-term ANP infusion (before-->48 h). Moreover, in eight patients with long-term ANP infusion, these hemodynamic effects were maintained at 7 days after initiating ANP infusion. Vasodilating, pulmonary vasorelaxant, and diuretic activities of ANP are maintained without tolerance, and thus long-term ANP infusion is clinically useful in patients with severe acute heart failure. 相似文献
109.
Yoko Okumura MSc Yoshihisa Nasa PhD Atsushi Sanbe PhD Wakako Toga BSc Satoshi Takeo PhD 《Journal of cardiac failure》1996,2(4):301-310
Background:
Despite the clinical relevance of angiotensin I-converting enzyme (ACE)inhibitors, their effects on impaired vascular function in patients and animals with chronic heart failure (CHF) have not been fully understood. This study was undertaken to determine whether long-term treatment with an ACE inhibitor improved the altered contractile properties of vessels from rats with CHF.Methods and Results:
Twelve weeks after coronary artery ligation, the rats were sacrificed and the isometric tension development of thoracic aorta, pulmonary artery, and mesenteric artery with and without endothelium was examined. Contractile responses to norepinephrine and prostaglandin F2α were augmented in endothelium-intact, but not in endothelium-denuded, thoracic aorta and pulmonary artery segments of the rat with CHF. The contractile response to angiotensin II was augmented in endothelium-denuded mesenteric artery segments of the rat with CHF, which was attenuated by indomethacin or diclofenac sodium but not by bunazosin. Trandolapril (3 mg/kg/d) was administered orally from the 2nd to 12th week after the operation. Treatment with trandolapril reversed the augmented contractile response of the rat with CHF to norepinephrine, prostaglandin F2α, and angiotensin II almost to the levels in the sham-operated rat.Conclusions:
The results demonstrate that an ACE inhibitor is capable of reversing altered vascular function in the rat with CHF, suggesting that vascular beds are possible sites of action for ACE inhibitors in the therapy for CHF. 相似文献110.
The change of the cerebrospinal pressure wave from during the continuous monitoring of intracranial pressure is often experienced. We supposed that this phenomenon would be the result of the change of transmission of spinal fluid pulse through the cerebrospinal fluid (CSF) system. Our study was performed to determine the change of auto power spectrum of CSF pulse when CSF pressure was increased by the slow infusion of lactate linger solution. The spectrum of CSF pulse was found to be composed of four main waves; wave derived from the respiratory movement, fundamental wave of cardiac origin and its 2nd and 3rd harmonic waves. The power of waves derived from the cardiac beats were increased when CSF pressure was elevated by the slow infusion, but the degree of increment was larger in the fundamental wave than harmonic waves. Elevation of CSF pressure caused relative attenuation of the harmonic waves included in CSF pulse. From the result of this study we found that CSF system would have the function of "high-cut filter" and its cut-off frequency was lowered by the slow infusion of lactate linger solution. 相似文献