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Biomedical subjects

K Sunami

Publications and source records attributed to K Sunami.

At least 91 records · Page 5Linked to original sources

Study of regional cerebral blood flow in experimental head injury: changes following cerebral contusion and during spreading depression.

Changes in regional cerebral blood flow (rCBF) following fluid-percussion brain injury (cerebral contusion) were studied in rats using the autoradiographic method. The direct current potential was monitored to identify spreading depression (SD). The rCBF was measured during SD and 2, 4, and 24 hours after injury. rCBF was almost nil in the contused area and decreased considerably in the cortices of the injured side for 4 hours after insult, then recovered by 24 hours. Focal relative rCBF increase occurred in the parietal cortex during SD, and was probably hyperperfusion due to SD. However, the rCBF did not increase over the sham-operated control. The injury probably caused hypoperfusion within 4 hours of insult and abolished the vascular response to SD.

Animals↗

[Hemorrhagic type of moyamoya disease].

Clinical picture of Moya Moya Disease was analyzed in 18 cases. In 16 cases whose CT scan were available at the time of the first bleeding, hematoma at the basal ganglia was noted in 43.8%, primary ventricular hemorrhage in 37.5%, thalamic hemorrhage with ventricular rupture in 12.5% and subcortical hemorrhage in 6.3%. The frequencies shown above were well correlated to previous reports. In MRI performed 1 year or more after primary ventricular hemorrhage, the primary bleeding site was demonstrated at the lateral wall of the lateral ventricle, in proton weighted and T2 weighted images. MRI can detect the site of old bleeding points and its chronological change if the study is repeated. In a follow-up period of 5.4 years, 27.8% of the cases had rebleeding one or more times. As a result, good outcome was noted in 72.2% after the 1st bleeding, and in 55.6% after re-bleedings. Death occurred in 5.6% of patients after the 1st bleeding and in 22.2% after further rebleeding. Rebleeding worsened the outcome. Therefore, prevention of rebleeding is important. From a therapeutic viewpoint, although a direct relation between rebleeding and untreated hypertension could not be established, blood pressure control is critical at both the acute and the chronic stages. Reconstructive vascular surgery is a recommendable method for properly selected patients.

Adult↗

[Intravenous DSA as a screening method for cerebral aneurysms].

Intravenous DSA (IVDSA) was evaluated as a screening method for cerebral aneurysms. It was performed 390 times in 372 cases. Clinically useful images were obtained in 94.1% in all examinations. Nineteen aneurysms were visualized in cerebral angiography among 21 cases with SAH or 3rd nerve palsy, whereas in IVDSA 15 aneurysms were noted. Aneurysms not visualized in IVDSA were all 4 mm or less in size. Therefore, aneurysms, more than 4 mm in size, which have higher risks for rupture, were detectable in IVDSA. Based on these findings, IVDSA is considered to be clinically useful in screening for aneurysms. In all 372 cases, 33 aneurysms were suspected in IVDSA findings, whereas in cerebral angiography 21 of them turned to be aneurysms. Such 12 false positive cases were distributed mainly at anterior communicating and middle cerebral arteries. Improvement of image resolution, avoidance of vessel overlapping and proper selection of screened cases should be investigated for further development of this screening method.

Angiography, Digital Subtraction↗

Changes of local cerebral glucose utilization, DC potential and extracellular potassium concentration in experimental head injury of varying severity.

The negative shift of DC potential was associated with an increase of extracellular potassium and energy metabolism. Therefore this dramatic phenomenon following the trauma to the brain was thought to be identical to spreading depression. 1. Spreading depression was most frequently observed between one and two hours after injury. 2. Spreading depression can be elicited in the deep structures as well as in the cortex. The more severe the injury, the more frequently the negative shifts were observed. The DC index seems to correlate well with the severity of the experimental model. It is concluded that the energy metabolism after the brain contusion was different from structure to structure and was changing continuously in the course of time.

Animals↗

Hypermetabolic state following experimental head injury.

Local cerebral glucose utilization (LCGU) was studied in 35 conscious rats after a fluid percussion injury (cerebral contusion). The experiments were divided into two parts. (I) Natural course: LCGU was quantitatively measured in 17 rats by the 14C-deoxyglucose autoradiographic method (Sokoloff et al. 1977) at 1, 2, 4 and 24 hours after injury. Sham operation was made in six rats. (II) DC-potential and LCGU: LCGU was studied with DC-potential and EEG monitoring in 12 rats. Results were as follows: (I) i) Glucose uptake was reduced at the center of the contusion in all cases. ii) Two different effects were observed in LCGU change two hours after injury: normal or slight increase in four of six rats (type A) and a remarkable increase in the cortex of the injured hemisphere in two of six rats (type B). iii) The pattern of increase in LCGU (type B) resembles that of cortical spreading depression. (II) i) Negative shift of DC-potential concomitant with EEG suppression in the injured hemisphere was observed frequently one to two hours after injury. ii) The increased LCGU pattern during DC-potential negative shift was identical with that of type B. iii) LCGU pattern without DC-potential change resembles that of type A. We concluded that the hypermetabolism occurring in the damaged cortex was due to a spreading depression. The findings obtained here should yield very important information concerning pathogenesis and treatment of human head injury.

Animals↗

Spreading depression following experimental head injury in the rat.

The direct current (DC) potential and electroencephalographic (EEG) changes were continuously monitored following fluid percussion head injury (brain contusion) in 10 conscious rats. Local cerebral glucose utilization (LCGU) was measured by the autoradiographic [14C]deoxyglucose method. Measurement of LCGU was started at the lowest point of the first or second DC potential negative shift when it occurred, and 2 hours after contusion if no DC potential changes were observed. The DC potential did not change in four rats (Group A), whereas DC potential negative shifts together with marked suppression of EEG activity occurred at 54 +/- 6.9 minutes after injury in six rats (Group B). In Group A, LCGU was decreased nonsignificantly in both the right and left cortices. In Group B, however, LCGU in the lesioned cortex rose to 160-190% of the level observed in the contralateral cortex (p less than 0.05). The autoradiographic pattern in Group B was identical to that seen in spreading depression. These findings can contribute to the effort to better understand the pathophysiology of head injury.

Animals↗

[A case of bronchial asthma and PIE Syndrome induced by disodium cromoglycate].

A 54-year-old female with bronchial asthma and PIE syndrome induced by disodium cromoglycate (DSCG) was reported. She was referred to our hospital for further examination of the abnormal chest shadows and eosinophilia. She had been treated with DSCG, Cefaclor. Bromhexine and bronchodilator for bronchial asthma and bronchitis. Withdrawal of the drugs except for the bronchodilators alleviated her symptoms. Therefore, drug induced lymphocytes stimulation tests (DLST) were performed for those three drugs. Only DLST for DSCG showed a positive result. She had been asthmatic for ten years and treated by the drug for 18 months prior to admission. The skin test for the drug was negative and a precipitating antibody for the drug could not be found. To obtain a definite diagnosis, bronchial challenge by DSCG was performed, after her symptoms were under control. Severe asthmatic responses were provoked in 6 and 24 hours after the inhalation of DSCG. Bronchoalveolar lavage, performed 8 days after the provocation, revealed increased eosinophils and lymphocytes in BAL fluid. Although several cases of PIE syndrome induced by DSCG have been reported, this seems to be the first report of late and delayed type bronchial response and pulmonary infiltration with eosinophilia provoked by DSCG. The bronchial response to the drug was a late and delayed type reaction and sustained for a long period. This might indicate that PIE syndrome induced by the drug may be caused by a same mechanism as the provoked asthmatic response.

Asthma↗

[Changes in local cerebral glucose utilization, DC potential and extracellular potassium in various degree of experimental cerebral contusion].

UNLABELLED: Pathophysiology of the traumatized brain, especially that of cerebral contusion, is very complex and has not been well understood. In recent years, changes in extracellular ion concentration have been known in various pathological conditions such as cerebral concussion, spinal contusion, ischemia, hypoglycemia, epilepsy and spreading depression as one of the triggers to lead to secondary brain damage. To know the metabolic and ionic changes following cerebral contusion, the authors made various degree of cerebral contusion by fluid percussion method, and observed successive changes in EEG, DC potential, extracellular potassium concentration and local cerebral glucose utilization (LCGU). MATERIALS AND METHODS: Using 42 male Wistar rats, mild (0.2 kg/cm2), moderate (0.4 kg/cm2) and severe contusion (0.6 kg/cm2) were made in the left lower parietal region of the rats. EEG, DC potential and extracellular potassium concentration (using potassium sensitive glass microelectrode) were monitored for four to five hours after making the contusions. LCGU (by 14C-2-deoxyglucose method) was studied at the time of the negative shift of DC potential. RESULTS: The negative shift of DC potential with EEG suppression was observed at 30 min. to 3 hours after injury. The severer the injury was, the earlier and the more frequent negative shifts appeared. LCGU showed no significant changes in the mild injury group. In the moderate injury group, frequent negative shifts of DC potential associated with EEG suppression were observed. A 20% increase of glucose utilization in the cortex of the lesion side was observed whereas 50% decreases in the subcortical structures were found. In the severe injury group, EEG was suppressed immediately after contusion and had never recovered. DC potential fluctuated and was unstable. The increase of LCGU was noted not only in the cortex of the lesion side but also in some of the subcortical structures (hippocampus, caudate nucleus, dentate nucleus and thalamus). The extracellular potassium concentration rose to 30 mM, being correlated closely with DC potential. DISCUSSION: Increase of LCGU associated with EEG suppression, negative shift of DC potential and elevation in extracellular potassium concentration was thought to be due to spreading depression. It was postulated that spreading depression following cerebral contusion causes energy failure and can lead to secondary brain damage.

Animals↗

[The clinical significance of Creola body in the sputum of asthmatic patients].

In order to clarify the relationship between agglomerated bronchial epithelial cells, i.e. Creola body (CrB), in the sputum and each pathogenetic factor of bronchial asthma, the incidence of CrB in sputum stained by Papanicolaou's method and observed under a light microscope was evaluated in 45 cases of bronchial asthma and 9 cases of obstructive pulmonary diseases. The following results were obtained: 1) CrB was observed specifically in the sputum of patients with bronchial asthma. In comparison with CrB-negative cases, CrB-positive cases had a greater number of days with attacks and a higher incidence of eosinophils in the sputum. 2) The presence of CrB in the sputum tended to be at a high rate in non-atopic cases with low serum IgE values, but had no obvious correlation with either the incidence of neutrophils in the sputum, the present age of the patient, the severity of the disease or bronchial hyperresponsiveness to methacholine. These results suggest that the involvement of histolesionable factors such as persistent bronchial contraction and release of major basic protein from eosinophils in the airway may lead to the formation of CrB.

Adult↗

A twin study of febrile convulsions in the general population.

Seven monozygotic (MZ) and six dizygotic (DZ) twin pairs with febrile convulsions (FC) in the general population were studied. The pairwise concordance rate for FC in MZ 85.7% (6/7) was higher than that in DZ 16.7% (1/6). In a discordant MZ pair, the unaffected co-twin was attacked by epileptic seizures later. Between the concordant DZ twins, the clinical symptoms and EEGs differed in quality. According to the ratio of concordance rate in MZ to that in DZ 5.1, a multifactorial mode of inheritance for FC was suspected.

Child↗

Spike EEG abnormalities in patients without epileptic seizures: a clinical and long-term follow-up study.

A study was conducted on a total of 850 patients who had not previously manifested any epileptic seizures but exhibited at least one spike EEG abnormality. They accounted for 7.2% of the total number of patients without epileptic seizures (850/11,773). Among the 850 patients, 564 were followed up for 1-24 years. Nine boys and one girl, i.e. 1.8% of the 564 patients, had manifested epileptic seizures during the observation period. They expressed the following six characteristics: males, first EEG examination at 0-4 years of age, onset of initial chief complaints at 0-6 years of age, mental retardation, spike and wave EEG abnormalities and past history of perinatal birth injuries. These factors are considered to be efficient in detecting patients liable to manifest epileptic seizures later.

Adolescent↗

[Three cases of involuntary movements following pontine hemorrhage].

We reported three cases with involuntary movements following pontine hemorrhage. All cases had various symptoms indicating brain-stem lesions, but the consciousness and motor functions were not severely disturbed. CT scans showed a small hematoma localized in unilateral pontine tegmentum in all cases. Intention tremor developed six to ten months after the hemorrhage when the initial neurological symptoms were almost relieved. Electromyogram (EMG) showed a rhythmic 3-4 Hz alternating or synchronized tremor pattern which was induced by finger-nose test and arm stretching. In one case which had showed bilateral horizontal gaze palsy indicating bilateral PPRF involvement in the acute stage, spontaneous vertical nystagmus was observed when the tremor developed. Electronystagmogram (ENG) and its differential calculus showed a pendular nature of the eye movement. This abnormal eye movement did not disappear while the patient was asleep. This case also developed a palatal myoclonus in the chronic stage. Magnetic resonance images (MRI's) obtained one to three years after the hemorrhage revealed a lesion localized in hemipontine tegmentum. The responsible lesion of these involuntary movements was thought to be located in pontine tegmentum from the MRI findings. The functional Prognosis of small hemorrhage in unilateral pontine tegmentum is generally good, but care should be taken for the possibility of late development of various types of involuntary movement.

Cerebral Hemorrhage↗

The effects of mazindol on local cerebral glucose utilization in rats.

The effects of mazindol (1 mg or 10 mg/animal, p.o.) on local cerebral utilization of glucose were studied by the quantitative autoradiographic [14C]2-deoxyglucose method in conscious adult male rats. Significant increases in local cerebral utilization of glucose were observed 2 hr after administration of 10 mg of mazindol in 10 out of 37 anatomically discrete regions examined. These 10 areas included regions rich in dopaminergic receptors (substantia nigra, globus pallidus), and also regions with few dopaminergic receptors (cerebral cortex, thalamus, cerebellum). Only the habenular nucleus showed a significant decrease in utilization of glucose induced by the administration of 10 mg of mazindol. No significant changes in local cerebral utilization of glucose were observed following the administration of 1 mg of mazindol. The fact that the pattern of utilization of glucose observed in this study resembled that produced by apomorphine, a putative dopaminergic agonist, indicates that the pharmacological effects of mazindol are related to the dopaminergic system.

Animals↗