Showing papers by "Osamu Sato published in 1998"
TL;DR: The development of anastomotic aneurysm is not influenced by any factor specific to this disease except the presence of an aneurYSmal lesion, and can occur anytime after operations for Takayasu's arteritis.
78 citations
78 citations
TL;DR: It is emphasized that postnatal prognosis is not simply a function of the form of the diagnosis but is also dependent on the progression of hydrocephalus and the degree to which that process affects neuronal development.
Abstract: Object. It is possible to diagnose hydrocephalus prenatally based on the morphological appearance of the fetus on neurodiagnostic images; however, the prognosis of this disease shows wide variation. The authors previously proposed a classification system for the prediction of postnatal outcome based on progression of hydrocephalus and affected brain development, known as the “Perspective Classification of Congenital Hydrocephalus (PCCH).” In this study the authors have used their classification system to analyze long-term follow-up results obtained in each clinicoembryological stage of fetal hydrocephalus. Methods. Sixty-one fetuses with hydrocephalus were examined to predict postnatal outcome by using this newly developed classification. The authors' recently developed method of using heavily T2-weighted imaging with a superconducting magnet clearly delineated the cerebrospinal fluid (CSF) space and the malformed brain and spinal cord. Imaging was achieved in less than 1 second per slice and required no ...
69 citations
TL;DR: In this article, the authors applied peripheral pulse gating, which had been optimized to reduce artifacts in the cisterns attributable to cerebrospinal fluid (CSF) flow, and determined the delays as a function of the time elapsed between two consecutive peaks of pulse wave.
Abstract: Object. To assess its usefulness in demonstrating cisternal anatomy, the authors investigated magnetic resonance (MR) cisternography in which a heavily T2-weighted turbo spin—echo method was used to visualize normal anatomical fine structures and lesions in the basal cisterns in 20 healthy volunteers and 43 patients. The authors applied peripheral pulse gating, which had been optimized to reduce artifacts in the cisterns attributable to cerebrospinal fluid (CSF) flow. Methods. The detectability of each cranial nerve was determined in healthy volunteers. The first, second, and third nerves and the seventh—eighth nerve complex were clearly visualized in all participants; the fifth nerve was clearly seen in 80% and the sixth cranial nerve in 50%. The fourth nerve and the ninth through 12th nerves were difficult to identify individually, except in some volunteers. To reduce artifacts caused by fast CSF flow, we determined the delays as a function of the time elapsed between two consecutive peaks of pulse wave...
51 citations
TL;DR: It is demonstrated that the lateral circumflex femoral artery can provide a suitable midway outflow for aortopopliteal bypass in patients with extensive thrombosis of the iliofemoral arteries.
Abstract: We describe herein the case of a patient who presented with total occlusion of all the major arteries in the unilateral iliofemoral region, including the distal deep femoral artery, on whom an aortolateral circumflex femoral-popliteal artery sequential bypass was successfully performed. This case report serves to demonstrate that the lateral circumflex femoral artery can provide a suitable midway outflow for aortopopliteal bypass in patients with extensive thrombosis of the iliofemoral arteries.
22 citations
TL;DR: In this article, the external magnetic field effects on the photoinduced magnetization of a cobalt iron cyanide, K 0.4Co1.3[Fe(CN)6]·5H2O was studied.
Abstract: We studied the external magnetic field effects on the photoinduced magnetization of a cobalt iron cyanide, K0.4Co1.3[Fe(CN)6]·5H2O. Photoinduced magnetization value was increased ca. 20 % at maximum under the magnetic field of 50000 G at 5 K. In addition, in the ferrimagnetic region (T < Tc = 26 K), the external magnetic field accelerated the rate of photoinduced spin generation. Those data suggest that external magnetic field increases magnetic interaction between the excited state and spin clusters.
16 citations
Journal Article•
TL;DR: The restricted TCR gene usage suggests that a certain autoimmune mechanism was involved in the pathogenesis of this case similar to Takayasu's arteritis, in which massive infiltration of delta T lymphocytes and strong expression of HSP-65 in the aortic tissue are characteristic.
Abstract: We report a rare case of an atherosclerotic aortic aneurysm with lymphocyte infiltration in which T-cell receptor (TCR) Valpha as well as Vbeta gene usage was restricted. Immunohistochemical studies showed that the infiltrating cells mainly consisted of macrophages, natural killer (NK) cells, cytotoxic T lymphocytes (CTLs) and T-helper (Th) cells, and that there were almost no infiltrating delta T lymphocytes, and human leukocyte antigen (HLA) class I and 65-kD heat-shock protein (HSP-65) was not strongly expressed in the aortic tissue. Although the immunohistochemical data were consistent with an ordinary atherosclerotic aortic aneurysm, in which TCR Valpha-Vbeta gene usage is known to be polyclonal, the restricted TCR gene usage suggests that a certain autoimmune mechanism was involved in the pathogenesis of this case similar to Takayasu's arteritis, in which massive infiltration of delta T lymphocytes and strong expression of HSP-65 in the aortic tissue are characteristic.
9 citations
TL;DR: The experience of this case suggests that primary closure for defects in both the aorta and the esophagus is the best option when the defects are small, and that the possibility of an AEF must be considered in patients with midthoracic pain or hematemesis, even if there is no history of thoracic aortic aneurysm, foreign body ingestion, trauma, or esophageal disease.
Abstract: We report herein the case of a patient with an aortoesophageal fistula (AEF) who was managed successfully by surgery. A 5-mm oval, well circumscribed aortic perforation just above the orifice of the celiac axis and a 4-mm defect in the esophagus were primarily closed, and an omental flap was placed between the aorta and the esophagus. No definite etiology could be determined. Our experience of this case suggests that primary closure for defects in both the aorta and the esophagus is the best option when the defects are small, and that the possibility of an AEF must be considered in patients with midthoracic pain or hematemesis, even if there is no history of thoracic aortic aneurysm, foreign body ingestion, trauma, or esophageal disease.
6 citations
TL;DR: In this paper, the electronic states of Fe atoms in Co[Fe(CN)5NH3\(\cdot x \)H2O were studied by means of 57Fe Mossbauer spectroscopy.
Abstract: The electronic states of Fe atoms in Co[Fe(CN)5NH3\(\cdot x \)H2O were studied by means of 57Fe Mossbauer spectroscopy. The Mossbauer spectra of Co[Fe(CN)5NH3\(\cdot \)6H2O show the coexistence of mixed valences for the Fe atoms and a magnetic relaxation at 4 K. When water molecules were removed, electron transfer from Co to Fe occurred.
3 citations
Journal Article•
TL;DR: Popliteal-distal bypass is a reliable procedure in selected patients with OPA and no occlusive progression in the inflow artery is revealed, and the background of the patients and the surgical results, including long-term patency and postoperative arteriographic findings are studied.
Abstract: OBJECTIVE To clarify the clinical features of chronic arterial occlusive disease in which the main lesion occurs in the popliteal artery (OPA). EXPERIMENTAL DESIGN This was a retrospective study with a follow-up of 1 to 163 months. SETTING A department of surgery in a university hospital. PATIENTS Fifty-six patient who underwent tibioperoneal bypasses: 31 patients with OPA, and 25 with an extensive occlusive lesion from the femoral to popliteal artery (OFPA). INTERVENTION All bypasses were performed using reversed saphenous veins under tourniquet ischemia. MEASUREMENTS The background of the patients and the surgical results, including long-term patency and postoperative arteriographic findings. RESULTS Buerger's disease occurred most commonly in the OPA group (49%) and arteriosclerosis obliterans occurred most commonly in the OFPA group (64%). The 3-year primary and secondary cumulative patency rates of the grafts for OPA were 72% and 85% respectively, and were comparable with those of OFPA. Arteriographic analyses carried out in the follow-up period revealed no occlusive progression in the inflow artery. CONCLUSIONS Popliteal-distal bypass is a reliable procedure in selected patients with OPA.
2 citations
TL;DR: In this article, a vanadyl phthalocyanine (VOPc) film (phase I) was prepared and photo-induced phase transition of VOPc was tried.
Abstract: A vanadyl phthalocyanine (VOPc) film (Phase I) on a mica substrate was prepared and photoinduced phase transition of VOPc was tried. Changes in absorption spectra show that Phase I structure is converted to Phase II structure by the irradiation with He-Ne laser. The surface structural changes of VOPc were also observed by using atomic force microscopy (AFM). Experimental results suggest that the phase transition was induced by photo-thermal processes.
TL;DR: Postreconstructive flowmetry reflected the severity of intraluminal defects of runoff arteries; however, the fates of these changes could not be predicted by use of completion arteriography or intraoperative magnetic flowmetry.
Abstract: Intraluminal filling defects of the runoff arteries, which were transient in most cases, are frequently observed on completion arteriograms after crural arterial reconstructive procedures. However, the incidence, fate, and significance of these changes have yet to be clarified. Completion arteriograms of 108 bypasses were evaluated retrospectively. The incidence of intraluminal defects of runoff arteries was examined by measuring the internal diameter on completion arteriograms and its relationship to the distal anastomotic site, underlying disease, and time the artery was ischemic, and the results of intraoperative magnetic flowmetry were analyzed. These changes were compared with those revealed by subsequent postoperative arteriography. The incidence of arterial defects was 46% (50/108) and was higher in bypasses to more distal arteries (P<0.0001) and Buerger's disease patients (P<0.0001). Ninety percent (45/50) were transient. Postreconstructive flowmetry reflected the severity of intraluminal defects of runoff arteries; however, the fates of these changes could not be predicted by use of completion arteriography or intraoperative magnetic flowmetry.