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Biomedical subjects

N Yasui

Publications and source records attributed to N Yasui.

At least 253 records · Page 14Linked to original sources
PubMed1985

[Angiographic analysis of the middle cerebral artery in cerebral aneurysms--its branching pattern and so-called vascular anomalies].

UNLABELLED: Branching patterns of middle cerebral artery (MCA) were angiographically analyzed in 704 cases with cerebral aneurysms. The mean age was 53 years old and the men-to-women ratio was 1.1. In addition, 13 vascular anomalies of MCA were reported and their correlation with the occurrence of cerebral aneurysm was studied. RESULTS: MCA branching patterns were classified in 6 types. Each type was further studied by dividing into 2 subgroups, namely one with MCA aneurysms at their side and the other without MCA aneurysms. There were no differences statistically between each two groups. Vascular anomalies were consisted of 5 duplications of MCA, 4 fenestrations, 3 accessories and one case of combination of duplication and accessory in the same side. Duplications and accessories did not have any evidence of developing aneurysm more frequently at their bifurcation than any one of normal MCA branching patterns. So we concluded that duplications and accessories should be thought to have similar meanings with the ordinary branching patterns of MCA in the occurrence of aneurysms. A postmortem case of accessory MCA without aneurysm revealed that the origin of the anomaly was pathologically normal. We suggested that the origin of accessory MCA could both be an enlarged Heubner artery and a rare branching pattern of MCA. The fenestration should be a true anomaly but at this point we do not have any suggestive clue for that. Finally, we thought that the combination of duplication and accessory in a single MCA was very rare morphologically, and worthwhile to report.

Adult↗
PubMed1985

[Angiographic analysis of the internal carotid-vertebrobasilar system with cerebral aneurysms--with special interest in the morphological aspect including so-called vascular anomalies].

In a series of 704 aneurysm patients who were admitted to the Research Institute for Brain and Blood Vessels-AKITA during the last 9.5 years (from October, 1974 to March, 1983), angiographic features of the internal carotid-vertebrobasilar system and related vascular anomalies were analyzed with reference to the site of aneurysms. The age distribution was from 20 to 78 years (mean age 53 years) and the men to women ratio was 1:1.1. The total number of the aneurysms was 866. The site distribution of aneurysms consisted of 230 (27%) anterior communicating, 269 (31%) middle cerebral, 282 (38%) internal carotid, 54 (6%) anterior cerebral, 45 (5%) vertebrobasilar and 6 other arteries. More than one aneurysm were found out in 137 cases. The total number of performed cerebral angiograms was 1840, in which right carotid arterial angiograms were 652, left carotid 644 and vertebral 544. Angiographic features of the posterior communicating arteries (Pcom) with or without internal carotid-Pcom aneurysm were compared one side with the other, statistically revealing that the morphological factor of the Pcom did not play an important role in the development of the cerebral aneurysm at this portion. Anomalies of the posterior cerebral artery directly originated from the internal carotid artery were found in 9 cases, and three of them had the aneurysm at their origin. Anomalous carotid-basilar anastomoses were seen in 7 cases, namely 6 persistent primitive trigeminal arteries (2 of them were PTA variants) and one persistent primitive hypoglossal artery.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1985

[Angiographic analysis of the anterior cerebral arteries with cerebral aneurysms--with special interest in the morphological aspect including so-called vascular anomalies].

In a series of 704 aneurysm patients who were admitted to the Research Institute for Brain and Blood Vessels-AKITA for the last 9.5 years (from October, 1974 to March, 1983), angiographic features of the anterior cerebral arteries and related vascular anomalies were analyzed with reference to the site of aneurysms. The age distribution was from 20 to 78 years (mean age 53 years), and the men to women ratio was 1:1.1. The total number of aneurysms was 866. The site distribution of aneurysms consisted of 230 (27%) anterior communicating, 269 (31%) middle cerebral, 282 (38%) internal carotid, 54 (6%) anterior cerebral, 45 (5%) vertebrobasilar and 6 other arteries. More than one aneurysm were found out in 137 cases. The total number of performed cerebral angiograms was 1840, in these right carotid arterial angiograms were 652, left carotid 644 and vertebral 544. Cases were divided into two groups, namely one who had the anterior communicating artery (Acom) aneurysm and the other who had not. Angiographic calibers of A1 portion (proximal portion of the anterior cerebral artery) were compared statistically between these two groups. As a result, three points as below were clarified in this series. 1) The Acom aneurysm group showed the significant asymmetry of A1 (p less than 0.005) compared to the other cases. 2) The left A1 portions were significantly dominant (p less than 0.05) to the right in the Acom aneurysm group. 3) Angiographic hypoplasias and aplasias of A1 were found in the Acom aneurysm group more frequently than in the other with statistical significance (p less than 0.005).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1984

Identification of a large interrupted helical domain of disulfide-bonded cartilage collagen.

In order to characterize a larger form of disulfide-bonded cartilage collagen, explants of 17-day embryonic chick sterna were cultured in the presence of [3H] proline. Radioactive collagen chains and fragments that were synthesized and secreted into the culture medium were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and fluorography. After limited pepsin digestion of the medium, two discrete disulfide-bonded collagen fragments were detected with Mr = 210,000 and 153,000. These fragments contained 28 and 17.5%, respectively, of the radioactivity in the alpha 1(II)-chains. The smaller fragment (called M) produced three components upon reduction (Mr = 104,000, 51,000, and 31,000) and seemed to represent the previously reported collagens, HMW and M1. The larger fragment (called N) has not been previously described and gave rise to three components upon reduction (Mr = 140,000, 69,000, and 49,000). Prolonged pepsin treatment resulted in the gradual decrease of N with a corresponding increase of M, suggesting the conversion of N to M. CNBr peptide mapping demonstrated that all M-derived peptides were present in N and that N contained extra peptides that account for its larger size. These observations suggest that N represents a larger more intact form of cartilage-derived disulfide-bonded collagen.

Animals↗
PubMed1984

Melorheostosis of the upper limb: a report of two cases.

The etiology, diagnosis, and treatment of two cases of melorheostosis are reported. The hyperostotic lesion corresponded well with both C7 and C8 segments of a sclerotome. The accompanying subcutaneous tumors in case 1 originated from the medical cutaneous nerve of the forearm, whose axons were coming mainly from the C8 dorsal root ganglion. These findings strongly suggest that the primary disorder exists in sensory nerves. Pain originating from the hyperostosis could be suppressed by the disodium salt of (1-hydroxyethylidene) diphosphonic acid.

Adult↗
PubMed1984

Intraoperative topical nimodipine after aneurysm clipping.

The lipophilic calcium antagonist Nimodipine (Bayer Pharma , Wuppertal ) was administered during aneurysm operations in 40 patients with ruptured intracranial aneurysm. Immediately after clipping of the aneurysm, a 2.4 X 10(-5) M solution of Nimodipine in 18 ml of Ringer's solution was injected into the subarachnoid space near the site of aneurysm clipping. Arterial vessels regularly dilated and spastic portions resumed their normal diameters. Since it is known from experimental work, that Nimodipine has stronger dilator capacity than papaverine and acts at least for several hours, two conclusions are drawn from the present preliminary study: Pre-operative vasospasm seen on angiograms is no longer a contraindication to early operation because spasm detected intraoperatively can be effectively treated. The long-lasting effect of Nimodipine prevents ischaemic complications in the first few days after operation and thereby seems to exert a protective effect against the onset of severe symptomatic vasospasm.

Administration, Topical↗
PubMed1984

Transitions in collagen types during endochondral ossification in human growth cartilage.

Immunohistochemical staining for Types I and II collagen in human growth cartilage showed that cartilage matrix consists of Type II collagen, whereas bone matrix contains Type I collagen. Endochondral ossification began with the deposition of Type I collagen by cells derived from bone marrow on the surface of the eroded cartilage. However, territorial matrix of the last hypertrophic chondrocytes contained both Types I and II collagen, thereby indicating that the degenerating chondrocytes initiate the synthesis of Type I collagen. This matrix, consisting of Types I and II collagen, is then replaced by newly formed osteoid.

Bone Development↗
PubMed1984

[Visual disturbances following right cerebral lesion: a case report].

A 49-year-old right handed male, who showed three types of visual disturbance, e. g. hemianopsia, obscuration phenomena and unilateral visuospatial agnosia at different times, was reported. At first, he had hemiparesis, hemisensory disturbance and homonymous hemianopsia on the left side because of multiple stenoses of posterior branches of the right middle cerebral artery. His motor and visual field disturbances improved for several days after onset, but there appeared transient obscuration phenomena on the left visual field. CT scan revealed an abnormal low density area in the right temporo-parietal region. At about 4.5 years after the first attack, he again had hemiparesis and homonymous hemianopsia on the left side. Cerebral angiography showed an occlusion of the right middle cerebral artery. Since his paresis was progressive, STA-MCA anastomoses was performed. Hemiparesis was improved, but homonymous hemianopsia remained. Moreover, at about one year after the second attack, left visuospatial agnosia participated in his hemianopsia. Cerebral angiography showed an additional occlusion in the crural segment of the right posterior cerebral artery. CT scan showed a lesion in the right basal ganglia and temporo-parietal lobe. In most cases, unilateral visuospatial agnosia occurs with hemianopsia. But, in this case, these symptoms occurred at different times. This may indicate the differentiation between unilateral visuospatial agnosia and hemianopsia.

Agnosia↗
PubMed1984

Chondrocytes embedded in collagen gels maintain cartilage phenotype during long-term cultures.

Chondrocytes isolated from sterna of 13-day-old chick embryos were cultured in vitro within collagen gels for six weeks. Under these culture conditions, chondrocytes assumed a rounded morphology, accumulated metachromatic matrix, and took on the cytological characteristics of in vivo cartilage cells. Most of the glycosaminoglycans synthesized were deposited within the collagen gels, and the rate of glycosaminoglycan synthesis was maintained over five weeks. Throughout the study, the major collagen synthesized was Type II. This cell-culture system, using collagen gels, provides chondrocytes with a suitable environment in which to accumulate synthesized matrix macromolecules and preserve their differentiated phenotype in vitro.

Animals↗
PubMed1984

[Angiographical extravasation in the intracranial hemorrhage due to cerebrovascular moyamoya disease--autopsy study].

A 53-year-old, non-hypertensive farmer, who had sudden attack of severe headache, was transferred to our clinic. He presented comatous state and tetraparesis without extraocular movements nor reactive pupils to light. CT scan, 7 hours after the ictus showed intracerebral hematoma in the right temporo-parietal region with ventricular extension. The following bilateral carotid angiograms established the diagnosis of the intracerebral hemorrhage due to cerebrovascular moyamoya disease. In angiograms of the affected side, irregular spotty stains spread from the periphei of the right posterior choroidal artery was delineated. The repeated CT scan after that indicated increment of hematoma. Fifty-three hours from the ictus, the patient died and an autopsy study was performed. After the fixation, the coronal brain section was made, and the careful observation of them elucidated the formation of an organized dissecting aneurysm in the angiographically extravasated vessel. About seven hundreds of serial specimen, 4 micron in thickness, was then investigated adjacent to the aneurysm. The organized dissecting aneurysm seemed to initiate from the branch of it, where marked fraying and undulation of the fibroelastic intima and internal elastic laminae were observed. The concavity toward the true lumen was completely disrupted and communicated to the extravascular space. As a result, the continuous part of it obstructed the lumen of the branch. These findings suggested the newly-developed dissection and it seemed to correspond to the angiographical extravasated points.

Arsenic↗
PubMed1983

Immunohistochemical localization of types I, II, and III collagens in the ossified posterior longitudinal ligament of the human cervical spine.

Immunohistochemical localization of types I, II, and III collagen in the ossified posterior longitudinal ligament of the cervical spine was studied using type-specific anticollagen antibodies. In contrast to the normal ligament which contains both types I and III collagens, the ossified matrix, composed of lamellar bone, contains only type I collagen, except for Haversian canals where type III is located in the inner wall. In the transitional region of preossifying ligaments, types III and I are both present. Type II collagen is present in the hyperplastic matrix of the ligament, and cartilage-like cells surrounded by type II collagen are aligned along nonossified ligaments adjacent to the preossifying region. A possible mechanism of matrix transition during the ossification process is given attention.

Adult↗
PubMed1983

Sarcoid disease of the wrist joint.

A case of destructive lesion due to sarcoidosis in the wrist joint is presented. The rarity of this site of occurrence and the rapid progress of this lesion are discussed.

Aged↗
PubMed1983

[Case of Moyamoya disease with agraphia caused by a frontal lesion].

A 45-year-old woman showed agraphia and decreasing spontaneity. She was diagnosed as Moyamoya disease by cerebral angiography. CT scans revealed the abnormal low density area in the left frontal lobe, and the regional cerebral blood flow study showed low perfusion in the bilateral frontal lobe and the left high convexity area. She could copy specimens of the author's writing, but her spontaneous writing and dictation were impaired with either hand. The form of each letter she wrote was not so distorted, but wrong letters were substituted for the correct ones. Errors in Kana-writing were more common than in Kanji. Although her spontaneous speech was diminished, auditory comprehension, reading and constructional abilities were unaffected. She exhibited no agnosia and apraxia. Agraphia in this case was caused by a disconnection between the visual image and auditory image and/or between the visual image and kinesthetic image. Inner speech (Luria, AR et al, 1968) in this case might be disturbed, and decreasing spontaneity and delay of response resulted from the frontal lesion. The writing process may be constituted of many factors; images of visual, auditory and kinesthetic as well as primary functions of sensory and motor. Furthermore, it may be necessary for normal writing that one's inner speech, activities and intention of writing behavior are intact.

Agraphia↗
PubMed1983

[The mechanism of unilateral spatial neglect].

We investigated a test for unilateral spatial neglect and discussed the mechanism of this symptom. Seventy eight patients with lesions on the right cerebral hemisphere were examined on line bisection, line cancellation, figure copying, clock drawing and location on the map. The statistical analysis revealed (1) there were no correlations between line bisection and clock drawing or between line bisection and location; (2) those with abnormal results on line bisection were apt to indicate normal results on line cancellation and figure copying, while in line cancellation, figure copying, clock drawing and location, normal results on one task meant normal results on the other. These results indicated clock drawing and location might include different factors from other tasks, line bisection was the most sensitive task for unilateral spatial neglect, and abnormality on line cancellation might be similar to that figure copying. Unilateral spatial neglect may be based on several disorders, and it may be assumed to have several aspects. One of these disorders may be defective searching. Unilateral spatial neglect may be more severe when there is sensory disturbance (hemianopsia) with a searching deficit. Other disorders, such as cognitive disturbance, memory disturbance and so on, may also be associated with unilateral spatial neglect, and it is necessary to consider the versatility of this symptom.

Adolescent↗
PubMed1982

Uptake and localization of 99mTc-methylene diphosphonate in mouse osteosarcoma.

The localization of 99mTc-methylene diphosphonate (99mTc-MDP) in mouse osteosarcoma was studied using a skeletal scintigraphic method and macro- and microautoradiographic methods. On the skeletal scintigraph, the tumor showed a high uptake of 99mTc-MDP and its concentration was about 20 times as high as the value seen in the muscular tissue. The macroautoradiography showed high activity in the tumor bone region and little activity in the nonossified region. On the microautoradiography, the activity of 99mTc-MDP was localized in the mineralized matrix of tumor bone and was almost nil in the nonmineralized matrix (osteoid) and the tumor cells. These findings indicate that the mineralization of the tumor bone matrix plays an important role in 99mTc-MDP uptake in osteosarcoma.

Animals↗