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Biomedical subjects

Y Maki

Publications and source records attributed to Y Maki.

At least 235 records · Page 13Linked to original sources
PubMed1980

Injuries of basal ganglia following head trauma in children.

7 pediatric patients with injuries of basal ganglia following head trauma were reported. They ranged in age from 10 months to 10 years. 5 boys and 2 girls comprised the patients. Cases 1--4 are mild cases in which the children fell down backward while playing, followed by a minimum loss of consciousness. In every case there was hemiparesis, but all of them showed remarkable recovery. CT findings are that of unilateral basal ganglia infarction. In cases 5--7, patients suffered from symptoms of brain contusion after running out in front of an oncoming car, and they developed hemiparesis. CT findings in cases 5 and 6 showed unilateral infarction. CT of case 7 showed a massive unilateral hemorrhage of the basal ganglia. All 7 cases sustained only slight scalp wounds and no skull fracture in spite of the severity of injuries signs and CT findings. This discrepancy seems to be explained only by the so-called shearing strain theory. But we have hypothesized that anterior stretch of the lateral branch of the perforator of the middle cerebral artery plays a major role in its pathogenesis.

Basal Ganglia↗
PubMed1980

Interaction of the antiallergic agent AA-344 with biogenic amines and prostaglandins in production of cyclic AMP in rat mast cells.

AA-344, which has been evidenced to inhibit selectively IgE-mediated allergic reactions, exhibited an inhibitory effect on cyclic AMP phosphodiesterase (PDase) in the homogenates of purified rat peritoneal mast cells (RMC). AA-344 showed synergistic effects with epinephrine, isoproterenol or prostaglandin E2 and F2 alpha in increasing cyclic AMP level in RMC: the combinations caused an increase in cyclic AMP 30-160 times as much as that caused by the respective agent alone. In the latter effect, AA-344 was at least 1,000 times as potent as theophylline. On the other hand, histamine or serotonin with or without AA-344 had no effect on the RMC cyclic AMP. These results obtained in vitro suggest that AA-344 may exert antiallergic action by increasing cyclic AMP via an interaction with epinephrine or prostaglandins which might be endogenously involved in regulation of a function of RMC in allergic reactions.

Amines↗
PubMed1980

[A procedure for recording electroretinogram (ERG) in conscious monkeys, and effects of some drugs (author's transl)].

Stable ERG was successfully recorded using a contact lens-type electrode in conscious cynomolgus monkeys restrained in a monkey-chair with a specially devised head-holder. After adaptation to darkness, single photostimulation evoked ERG consisting of an initial negative wave (a-wave), followed by a positive wave superimposed with oscillatory potentials (b-wave), and a late positive (c-wave). The former two waves were clearly recorded but c-wave was often mixed with artifacts probably due to eye movements. Amplitudes and peak latencies of a- and b-waves increased in progression of dark adaptation and attained to maximum within 20 min. The optimal intensity of photostimulus and time-constant for recording stable a- and b-waves with intermediate amplitudes were found to be 2 joule and 0.1 sec, respectively. The amplitudes and peak latencies (mean +/- s.d.) of a- and b-waves obtained by these conditions were 163.3 +/- 44.9 and 437.0 +/-37.9 microV, and 17.3 +/- 0.5 and 53.5 +/- 3.2 msec, respectively. These waves were reproducible within 25% variations change in a-wave: pentobarbital increased the amplitude of b-wave, whereas ketamine reduced this amplitude. A 3-day treatment with 1,5-di(p-aminophenoxy)pentane (200 mg/kg/day, p.o.), a retinal toxic and behavioral signs of visual dysfunction. Histological abnormality of the retina was also detected. The results indicate that this technique is useful for recording ERG in order to evaluate the effect of chronically treated drugs on visual perception in conscious monkeys.

Adaptation, Ocular↗
PubMed1980

[Chronic subdural hematoma--changed its density from low to high on follow-up CT (author's transl)].

Recently much attention has been paid once again to etiology of chronic subdural hematoma since the appearance of computed tomography (CT). Authors examined 1824 head injury cases by CT from January 1977 to September 1979. Among them, there are 40 cases (they were all over 16 years old) whose CT showed frontal extracerebral low density area. The low density area which is considered to be so-called fluid collection could be classified into four types (type I to IV). In two cases of those 40 cases (5%), the low density area changed into high density area which seemed to be hemorrhage. The 2 cases were diagnosed to be chronic subdural hematoma and proved surgery. The change of density on CT developed only from type I (the brain surface looks smooth and sulci are not recognized beneath the low density area). The change of density, occurred in 2 cases among 24 cases of type I (8.3%), was recognized about 2 months after the head injury. This fact is compatible with the report by Yamada et al. (1979). Thus, when CT after the head injury shows frontal extracerebral low density area of type I, the case may develop to chronic subdural hematoma about 2 months after the head injury. Therefore, careful observation should be needed especially during this period after the head injury.

Adult↗
PubMed1980

[Spontaneous spinal epidural hematoma--report of a case (author's transl)].

A typical case of spontaneous spinal epidural hematoma was reported. The patient was a 52 year-old male. He suddenly developed severe high back pain followed by complete paraplegia and rectovesical insufficiency. Myelography disclosed epidural mass extending fro Th2 t0 Th4. Laminectomy and removal of hematoma were carried out 4 days after the onset. Post-operative course was uneventful. Four months later he began to walk with the aids and 7 months later he was fully ambulatory and discharged. We analysed 110 cases already reported including our own and obtained the following conclusions. Spontaneous spinal epidural hematoma was 67% and secondary one 33%. The most frequent precipitating factor was usage of anticoagulant followed by trauma and vascular anomaly. There were relatively many case below the age of 15. The level of lesion predominated in thoracic region. Early operation was imperative but even in delayed cases good result could be expected especially in younger patient and those with lumbal lesion.

Age Factors↗
PubMed1980

[Computed tomography in diagnosis and management of acute head injury--correlation between clinical symptoms and CT findings (author's transl)].

A series of 202 patients with acute head injuries was investigated in correlation with clinical signs and computed tomographical findings. Clinical signs were classified into four types according to ARAKI's grading. Ninety three cases of type I, 61 cases of type II, 41 cases of type III and 7 cases of type IV were included in this series. The youngest patient was 40 days old and the oldest was 83 years old and average age was 31.3 years old. Initial C.T. was carried out in 70.80% of this series within 2 days after injury. Conclusions were obtained as follows: 1) Intracranial hemorrhages were recognized in 5.4% of type I, 18.0% of type II, 68.3% of type III and 100% of type IV on C.T. 2) All of intracranial hemorrhage in type I and type II were small and limited ones and showed no mass effect on C.T. 3) In all of severe cases with deep coma, their C.T. demonstrated poor visualization of so-called pentagone, ambient cistern and quadrigeminal cistern. These findings especially that of quadrigeminal cistern image were considered to be signs of poor prognosis. 4) Incidence of visualization of Sylvian fissure decreased in order of type I, type II, type III and type IV on C.T. Poor visualization of Sylvian fissure may reflect of small lesion in or out of cortex near Sylvian fissure such as small intracerebral hemorrhage, localized brain edema, small epidural hematoma etc. 5) Incidence of visualization of sulci decreased in order of type I, type II, type III, and type IV. Poor visualization of sulci may reflect existence of small lesion in or out of cortex in vertex area. 6) False negative of false positive finding on C.T. can result from slice level or time of C.T. and/or age of patient. Repeated C.T. may be recommended when the patient has conflicting neurological signs for these C.T. findings.

Adolescent↗
PubMed1979

A case of tuberous sclerosis with calcification of angiomatous change in the white matter.

A 5-year-old Japanese boy had had infantile spasms at 5 months of age, and had intractable seizures, adenoma sebaceum and prominent tramtrack-like calcification in the left occipital pole at five years. A neurosurgical operation was performed for the resection of the left occipital focus. Pathological examination showed patchy glial fiber nets on the cortical surface, scattered dysgenetic giant cells both in the cortex and white matter, and calcified angiomatosis in the white matter. These findings correspond to those of tuberous sclerosis and calcified angiomatosis in the white matter.

Angiomatosis↗
PubMed1979

A new nonsteroidal analgesic-antiinflammatory agent. Synthesis and activity of 4-ethoxy-2-methyl-5-morpholino-3(2H)-pyridazinone and related compounds.

In order to examine analgesic and antinflammatory activities, various 2-alkyl- or 2-alkenyl-4-alkoxy-5-(substituted amino)-3(2H)-pyridazinones were prepared. Among the compounds prepared, 4-ethoxy-2-methyl-5-morpholino-3(2H)-pyridazinone (8) was evaluated to be the most attractive compound as an analgesic-antiinflammatory agent. Compound 8 was shown to be more potent in analgesic and antiinflammatory activities and less potent in toxicity than aminopyrine and phenylbutazone. Some pyridazinone derivatives in which possible active sites of 8 are eliminated and altered were prepared, and their activities were evaluated by means of analogous assays. On the basis of available data, the structure-activity relationship in a series of 4-alkoxy-2-substituted-5-(substituted amino)-3(2H)-pyridazinones was also discussed.

Acetates↗
PubMed1979

Studies on antianaphylactic agents. 6. Synthesis of some metabolites of 6-ethyl-3-(1H-tetrazol-5-yl)chromone and their analogues.

The metabolites of 6-ethyl-3-(1H-tetrazol-5-yl)chromone (AA-344) (1), an orally effective antiallergic agent, and their analogues were synthesized to confirm the proposed structures and to determine their activity in the rat passive cutaneous anaphylaxis (PCA) test. A glucuronic acid metabolite (6) was assigned the structure 24b, 1-deoxy-1-[5-(6-ethylchromon-3-yl)tetrazol-1-yl]-beta-D-glucopyranuronate, by the comparison of 13C NMR, mass spectra, and TLC of isomeric compounds. In 13C NMR spectra, the shift difference of the tetrazole ring carbons between a pair of isomers was more remarkable than that of the glycosidic carbons. Therefore, the former is a useful criterion for distinguishing between such isomers. Some of the metabolities and analogues were active when administered intravenously, and two metabolites (2 and 3) were also effective upon oral administration.

Animals↗
PubMed1979

Familial occurrence of moya-moya disease: report of three Japanese families.

Three Japanese families with moya-moya disease in six patients are presented. These six patients were among 49 cases of confirmed moya-moya disease in our experience, and the familial incidence was more than 12%. A relatively high familial incidence (7%) was found in the total Japanese series emphasising the important hereditary components in the pathogenesis of the disease.

Adolescent↗
PubMed1979

Giant aneurysm of the distal portion of the posterior inferior cerebellar artery.

The authors report a case of a giant aneurysm of the distal portion of the posterior inferior cerebellar artery presenting the classical picture of a tumor of the posterior fossa. CT scan of a giant aneurysm reveals the clear margin and high density area of aneurysm wall, and the homogeneous and high density area of the organized thrombus in a cavity of the aneurysm.

Aged↗
PubMed1979

Computed tomography of Sturge-Weber disease.

Findings in computed tomography (CT) with or without contrast infusion were analyzed in 8 patients with Sturge-Weber disease. From the extent of calcification in the CT, Sturge-Weber disease can be classified into two types, localized and diffuse. The extent of calcification or cortical atrophy is predictable, if it can be shown that enhanced areas in contrast infusion CT truly represent leptomeningeal angiomatosis. Thus, using enhanced CT, the capacity of prediciton as to whether the patient will have a localized or diffuse type of disease will be possible with further observations.

Adult↗