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K Koshu

Publications and source records attributed to K Koshu.

At least 55 records · Page 3Linked to original sources
PubMed1983

[Simplified microdetermination of cerebral phospholipase A1, A2 and lysophopholipase].

The purpose of our study was to examine the ischemia induced enzymatic changes of decaylation-reacylation cycle of membrane phospholipids in dog brain. In this study, we developed new modified method for assay of phospholipase A1, A2 and lysophospholipase which is simpler and needs only a smaller amount of materials. For the first report, we introduced this new method and demonstrated some properties of phospholipase A1, A2 and lysophospholipase in dog brain. Crude enzyme solution for assays of phospholipase A1, A2 and lysophospholipase was gained from extraction of frozen brain with aceton, butanol and saline. The level of phosphorus in the enzyme extract was determined and only those extracts which had a level of phosphorus within a certain range were used. The substrates for assays were L-alpha-[beta-palmitoyl-1-14C] phosphatidylcholine, dipalmitoyl for phospholipase A1 and A2 and L-lysophosphatidylcholine-1-[1-14C] palmitoyl for lysophospolipase respectively. Each radioactive substrates was diluted with cold carrier lipid to give the proper specific activity. Reaction system including substrate, buffer [pH 7.0] and enzyme extract was incubated for 10 hours at 38 degrees C. But for the assay of phospholipase A1 and A2, enzyme solution was pre-incubated at 70 degrees C for 5 minutes. In our new method, reaction mixture was directly separated by TLC without extracting lipids. Enzyme activities were calculated from radio thin-layer chromatograms. Furthermore, we made a comparison between our method and the former one. The value of each enzyme activity was slightly higher in our method than in the former one. However, it was revealed that the results were reproducible in both methods.

Animals↗
PubMed1983

[Activities of phospholipase A1, A2, lysophospholipase and acylCoA: lysophospholipid acyltransferase in ischemic brain of the dog].

In this report, the sequential changes of phospholipase A1, A2, lysophospholipase and acylCoA: lysophospholipid acyltransferase activities in ischemic dog brain were investigated. The purpose of this study was to examine the enzymic changes of deacylation-reacylation cycle of biomembrane phospholipid in ischemia. Hemispheric non-blood supply models were produced by occlusion of main intracranial trunk arteries in dogs according to Suzuki's method. The sample was spooned out and frozen immediately with liquid nitrogen at the predetermined time. The assay of phospholipase A1, A2 and lysophospholipase activities was done by our method and acylCoA: lysophospholipid acyltransferase activity was according to Corbin and Sun's method. The activities of phospholipase A1, A2 and lysophospholipase did not show significant changes within 60 minutes after arterial occlusion. However these activities showed significant high value at 120 minutes and decreased gradually after then. On the other hand, acylCoA: lysophospholipid acyltransferase activity showed gradual decrease. These findings show that enzymic degradiation of acyl group of phospholipid in the brain is highest at about 120 minutes after complete ischemia. The importance of acyl groups of phospholipids for biomembrane structure and the function is well recognized. The turnover of these acyl groups in normal brain biomembrane is also well known. Some types of enzymic system related to this turnover has been investigated. Phospholipase A1, A2, lysophospholipase and acylCoA: lysophospholipid acyltransferase belong to these enzymic systems. There have been some reports that the content of free fatty acids in the ischemic brain increases in early stage.(ABSTRACT TRUNCATED AT 250 WORDS)

1-Acylglycerophosphocholine O-Acyltransferase↗
PubMed1982

[A case of the occlusion of the right middle cerebral artery due to congenital anti-thrombin III (AT III) deficiency (author's transl)].

The authors describe and discuss a case of the occlusion of the right middle cerebral artery due to congenital AT III deficiency. The patient, 23 years old, female, was admitted to our service with episodes of convulsive attacks, disturbance of consciousness and left hemiparesis on the fifth postoperative (laparotomy)day. She had been suffering from recurrent thromnbophlebitis of both legs. Right carotid angiogram revealed the occlusion of the trunk of the right middle cerebral artery about 13mm distal to its bifurcation. Routine laboratory findings on admission, including hematological tests, chemical tests of blood, liver function tests, kidney function tests, chest x-ray film and electrocardiogram, were within normal limits except leukocytosis. But examinations of coagulation and fibrinolysis showed decreased AT III activity and increased AT III antigen concentration. When examined her eight family members on the same examination, six individuals were affected with the decreased AT III activity. On about fourth hospital month, her neurological symptoms took a sudden turn for the worse again. But AT III concentrates transfusion and prescription of warfarin led to her striking clinical improvement. Eight cases of cerebral vessel disease due to congenital AT III deficiency were reported in literature. It is now concluded that AT III deficiency should be considered with one of the etiology of cerebral infarction and cerebral sinus thrombosis in young adults.

Adult↗
PubMed1981

CT findings in a case of neonatal acute subdural hematoma.

The CT findings in a case of neonatal acute subdural hematoma are presented. CT demonstrated a crescentic high density area in the subdural space over the left cerebral hemisphere and an oval high density area in the left occipital region. The latter was suspected of being an intracerebral hematoma. Emergency craniotomy revealed that the high density area was due to a subdural hematoma between the occipital lobe and the tentorium cerebelli.

Cerebral Hemorrhage↗
PubMed1981

Experimental hemorrhagic thalamic infarction in the dog.

As we have previously reported, a focus of cerebral infarction confined to the anterior half of the thalamus can be produced in the dog by simultaneously occluding four main arteries at the base of the brain. This knowledge was the basis of an investigation of hemorrhagic infarction following recirculation. In the animals after 6- to 12-hour occlusion, a high incidence of hemorrhagic infarction was found following recirculation. In brains autopsied 1 hour after recirculation, hemorrhagic infarction was seen in all of the dogs. The changes in regional cerebral blood flow and in computerized tomographic scans in this hemorrhagic infarction focus were also investigated.

Animals↗
PubMed1981

[The protective effect of mannitol and artificial blood (perfluorochemicals) on hemorrhagic infarction -- experimental study (author's transl)].

It has previously been thought difficult to produce hemorrhagic infarction in animals. Using the thalamic infarction model in the dog, the production of hemorrhagic infarction can be achieved consistently. In this study, the protective effect of mannitol and/or artificial blood (perfluorochemicals) on the hemorrhagic infarction was investigated. Adult mongrel dogs weighing about 10 kg each were used. Following temporal craniotomy, thalamic ischemia was produced by occluding four trunk arteries (the internal carotid, anterior cerebral, middle cerebral and posterior communicating arteries). Dogs which showed EEG changes indicative of thalamic ischemia were used in further experiments. The dogs were divided into 4 groups: (I) non-treated, (II) mannitol-treated, (III) fluorochemical-treated and (IV) mannitol and fluorochemical-treated. All dogs in each group underwent 6 hours of vascular occlusion followed by 1 hour recirculation. In order to evaluate the degree of hemorrhagic infarction, classification into 4 grades was done. Grade O: pale infarction without microscopical bleeding; Grade I: pale infarction wit microscopical bleeding; Grade II: a few sites of macroscopical petecheal bleeding; and Grade III: diffuse macroscopital petecheal bleeding. In the non-treated animals, autopsied brains showed hemorrhagic infarction in all cases. In mannitol-treated animals, some protective effect was found, especially in cases in which mannitol was administered within 60 minutes following occlusion. Hemorrhagic infarction was not suppressed in any of the fluorochemical-treated animals, but there was no hemorrhagic infarction in any of the animals treated with both mannitol and fluorochemicals. The present results are thought to indicate that these drugs administered together are effective in the treatment of hemorrhagic cerebral infarction.

Animals↗
PubMed1981

[Traumatic middle meningeal arterio-venous fistula--a case of bilateral occurrence (author's transl)].

A case of traumatic middle meningeal arterio-venous fistula was reported. The present case reported here appears to be unique because of its bilateral occurrence. As for traumatic middle meningeal arterio-venous fistula, we could not find any case with bilateral occurrence in the literature. Bilateral carotid angiograms revealed extravasation in the extradural spaces. Draining veins were found pouring into the superior sagittal sinus and also into the transverse sinus. This was also thought to be rare. We discussed to some extent on the etiology, diagnosis, angiographical findings and treatment of this disease.

Adult↗
PubMed1981

[A case of acute subdural hematoma in one-day-old baby--with special reference to its CT findings (author's transl)].

The authors describe and discuss a case of acute subdural hematoma originating from the lacerated tentorium of 22 hour-old newborn. CT scan revealed crescent high density area in the subdural space between the left frontal area and the occipital area. Another high density area was seen in the left occipital area which was suspected as intracerebral hematoma preoperatively because of its rather intramedullar location. Large craniotomy was performed 22 hours after delivery, evacuating 70 gm subdural hematoma. Bleeding point was determined as lacerated tentarium about 1 cm length. No intracerebral hematoma was found. Postoperative course was uneventful and he is showing normal development. It is now concluded that supratentorial subdural hematoma originating from tentorial laceration at delivery could be misdiagnosed as intracerebral hematoma on CT scan. Anatomical structure should be always compared when CT scan study is performed.

Acute Disease↗
PubMed1981

[An anterior communicating artery aneurysm complicated by chronic subdural hematoma--a case report (author's transl)].

A 53-year-old housewife was admitted to the Department of Neurosurgery, Toyama Medical and Pharmaceutical University on June 6, 1980, because of disorientation, urinary incontinence and left hemiparesis. She had experienced "a fit of severe headache" many times for five years. On May 12, 1980, she experienced an abrupt, severe headache in a lavatory and was immediately brought to a nearby hospital. Her symptom was recovered gradually for a week but she experienced sudden onset of severe headache again on May 20. Subsequently, her state of consciousness gradually worsened and left sided hemiparesis arose. On admission, cerebral angiograms revealed an aneurysm of an anterior communicating artery and a subdural hematoma over the right hemisphere. On the third hospital day, radical operation was performed by bifrontal craniotomy. Neck of aneurysm was ligated and clipped successfully and dark brownish semiliquid contents of chronic subdural hematoma was evacuated. The lacerated portion of arachnoid with some distance from the aneurysm was observed and subarachnoid hemorrhage was thought to enter subdural space through this portion. Post-operative course was uneventful. Nine cases of intracranial aneurysms complicated by chronic subdural hematoma were reported previously, but an anterior communicating artery aneurysm case was not in these cases. We have some discussion about cerebral aneurysms complicated by chronic subdural hematoma, especially about the pathogenesis of chronic subdural hematoma.

Chronic Disease↗
PubMed1981

[Measurement of regional blood flow using hydrogen gas generated by electrolysis (author's transl)].

Electrolytically generated hydrogen gas used to measure local blood flow by Stosseck et al. The data obtained by their method, however, did not correlated well with that obtained by original Aukland's method, hydrogen clearance method. We have tried to record the concentration of hydrogen gas after electrolytic generation of hydrogen gas at the white matter of the mongrel dogs. As a result, we found that its curves could be approximated to monoexponential curves during the first several minutes. This fact was also noticed in the experiment, in which circulation had been stopped due to cardiac arrest. A simple equation to calculate the regional blood flow was brought out through the approximation mentioned above. The values calculated by this new equation correlated well with that obtained by original hydrogen clearance method. This new method to detect the regional blood flow is simple and easy. Therefore it may contribute to some experiments, especially to the experiments with small animals.

Animals↗
PubMed1979

Spontaneous regression of posterior fossa dural arteriovenous malformation.

The authors report a case of infratentorial arteriovenous malformation that regressed spontaneously within 25 months without bleeding episodes or surgical intervention. The patient's clinical symptoms, left-sided tinnitus, cranial bruit, and right homonymous hemianopsia, disappeared completely over the same period.

Adult↗
PubMed1979

[Surgical treatment of the internal carotid-posterior communicating artery aneurysm--from the experience of 213 cases (author's transl)].

213 cases of so-called posterior communicating artery aneurysm submitted to surgical operation without using microscope were reviewed from the technical point of view. Aneurysm project boradly to two directions, i.e. postero-inferior and lateral directions. We have treated these anuerysms with two very distinct operative approaches in order to reach the aneurysmal neck from the right angle. Frontal approach is used for the aneurysms projecting laterally. In contrast, the aneurysms projecting postero-inferior are reached laterally by mobilizing the tip of the temporal lobe. Of 213 patients, 15 died (mortality rate 7.0%) and 19 were poor (8.9%). The operative result of the cases in which the aneurysm ruptured during the exposure of the aneurysmal neck was poor. Therefore, intensive care is emphasized to avoid the aneurysm rupture during surgery. Other important technical points which affect the operative results were discussed.

Adolescent↗
PubMed1979

[Spontaneous regression of a posterior fossa dural arteriovenous malformation (author's transl)].

A 29-year-old woman was admitted to our hospital because of dizziness, nausea and convulsive seizure. She complained of left sided tinnitus. Neurological examination revealed right homonymous hemianopsia, and systolic murmur on the left retroauricular area. Angiograms revealed a dural AVM in the left posterior fossa. Feeders of AVM were enlarged left occipital artery and middle meningeal artery. Since then she was treated only conservatively, but angiograms performed two years and one month later showed disappearance of the dural AVM. She experienced no head trauma, and no subarachnoidal hemorrhage. She has never been treated by irradiation nor contraceptives. We could find no clear mechanism for the spontaneous regression of the AVM.

Adult↗