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Biomedical subjects

K Kurata

Publications and source records attributed to K Kurata.

At least 109 records · Page 6Linked to original sources

A case of localization-related epilepsies suspected of panic disorder.

Some localization-related epilepsies have autonomic symptoms as well as psychic symptoms. As these symptoms are similar to those of panic disorder, it is important to discriminate between the two disorders. In such cases, VTR-polygraphic examination is necessary for the correct diagnosis.

Amygdala↗

Experimental study of the potential for contact sensitization and cross-reaction of imidazole antifungals.

We examined the potential for contact sensitization of miconazole nitrate and croconazole hydrochloride and the cross-reaction between them in guinea pigs by the maximization test of Magnusson and Kligman. Contact sensitivity was induced by croconazole hydrochloride in 5 out of 7 animals which, after being injected with 5% croconazole hydrochloride, underwent a closed patch with 25% croconazole hydrochloride. Contact sensitivity was not induced by miconazole nitrate. The 5 animals sensitized to croconazole hydrochloride were tested with 8 other imidazole antifungals and positive reactions were observed to oxiconazole nitrate in 2 of the 5 animals. This response may be a cross-reaction.

Animals↗

Differential effect of haloperidol on dopamine release and metabolism in caudate putamen and anteromedial frontal cortex using intracerebral dialysis.

The differential effects of haloperidol on dopamine release and its metabolism were investigated in the anteromedial frontal cortex and the caudate putamen using the intracerebral dialysis method in anesthetized rats after single intraperitoneal injections of 0.01, 0.125 and 2 mg/kg haloperidol. The basal levels of dopamine, 3,4-dihydroxyphenylacetic acid and homovanillic acid, collected every 20 min from the caudate putamen, were 22, 7.7 x 10(3) and 5.5 x 10(3) pg/30 microliters, respectively, and were much higher than those from the anteromedial frontal cortex, which were 1.8, 2.6 x 10(2) and 4.6 x 10(2) pg/30 microliters, respectively. There was a clear difference in the time-response curve of dopamine release between the two brain regions after the injection of 0.125 mg/kg haloperidol, but no difference after the administration of the other doses. The measurements of 3,4-dihydroxyphenylacetic acid and homovanillic acid showed a difference between the two brain structures after injection of the other doses. These findings suggest that there is a difference between the anteromedial frontal cortex and the caudate putamen with respect to the regulating mechanism of dopamine release and its metabolism.

3,4-Dihydroxyphenylacetic Acid↗

Middle ear pressures of children with otitis media with effusion.

Middle ear (ME) pressures were measured in 30 children with chronic otitis media with effusion (OME) transtubally with the use of a catheter pressure transducer (Mikro-tip, PC-330F). They were found to range from 40 to -185 mm H2O, the average being mildly negative (-54.33 +/- 59.04 mm H2O). About two thirds of these children had pulsating changes of ME pressure; the range of the pressure change was between 10 and 50 mm H2O. The ME pressure tended to be lower in ears with serous effusion than in those with mucoid effusion, but there was no significant difference between them.

Child↗

The beginning of Menière's disease.

Sudden deafness and low-tone hearing loss were treated by steroid therapy. Of the 106 cases of sudden deafness, 23 (21.7%) showed complete recovery, 36 (34.0%) remarkable improvement and 13 (12.3%) no change, while the results for the 56 cases of low-tone hearing loss were 32 (57.1%), 1 (1.8%), 16 (28.6%) and 7 (12.5%), respectively. Of all patients, 37 had onset of vertigo within 2 to 24 months after steroid therapy, and 17 patients, including 4 with horizontal type, 2 with deaf type and 11 with low-tone hearing loss, were diagnosed with Menière's disease. The final hearing gain for 4 cases of horizontal type and 2 cases of deaf type sudden deafness was very great. The 17 patients diagnosed with Menière's disease had hydrops of the inner ear.

Adolescent↗

[Cerebro-oculo-hepato-renal syndrome (Arima's syndrome) with slowly progressive renal insufficiency and epilepsy].

We reported an additional case of Arima's syndrome with slowly progressive renal insufficiency and epilepsy. The patient is a 20-year-old man whose parents are consanguineous. He had a history of mild asphyxia at birth, and unexplained tachypnea developed during the neonatal period. But it disappeared later, and he have had no respiratory problem since then. Physical examination on admission at the age of 19 years revealed bilateral blephaloptosis, narrow palate, searching nystagmoid movement, absence of light reflex, muscle hypotonia and wasting of extremities. Funduscopic study showed optic hypoplasia, choroid coloboma and narrowing of vessels. Head CT scan showed agenesis of cerebellar vermis and hypoplasia of brainstem. CT scan and echography of the kidney disclosed the bilateral multiple cysts. Liver was hyperechoic in echographic study; this finding is consistent with fatty change. EEG showed dysrhythmic slow wave activity with sporadic spike and wave complex. Compared with previously reported cases, the present case has the following features: (1) slowly progressive renal insufficiency, (2) generalized tonic clonic convulsion developing from the age of 11 months, (3) ABR abnormalities including the right-sided shortening of wave I-II interpeak latency and bilateral ill-defined wave V. Slow progress of renal failure in our case may reflect the mild pathological process of the kidney with sparing functional nephrons. It shows the diversity of the kidney pathology in Arima's syndrome. Epilepsy is a less common association in the syndrome, whereas EEG abnormalities were reported. ABR abnormalities may reflect the morphological alteration of the brainstem structure including auditory pathway. In our case it is uncertain whether the neonatal tachypnea was due to birth asphyxia or brainstem malformation responsible for abnormal respiration as suggested in Joubert's syndrome.

Adult↗

[Sodium regulation disorder, hypothermia, and circadian rhythm disturbances of the body temperature and sleep-wakefulness as sequelae of acute subdural hematoma].

We reported an 11-year-old boy who suffered from transient hypernatremia, hypothermia, and circadian rhythm disturbances of sleep-wakefulness and body temperature from the age of 4 years, as sequelae of acute subdural hematoma. T1-weighted magnetic resonance imaging (MRI) of the brain revealed low intensity consistent with necrotic change in the whole left cerebral hemisphere, hypothalamic region, and the right-sided brain stem including tegmentum, while the pituitary structure was well preserved. Anterior pituitary function was almost normal. ADH (antidiuretic hormone) was neither stimulated by hyperosmolality nor suppressed by hyposmolality but continued to be secreted at almost constant level approximating the normal basal state. This pattern seemed to be due to complete destruction of the osmoreceptor located in the anterior hypothalamus. He exhibited a dispersed-type sleep with differentiated stages of NREM (non-rapid eye movement), although the percentage of sleep was higher at night than in the daytime. It is suggested that circadian rhythm of sleep-wakefulness and differentiation of NREM sleep stages are regulated by different neuromechanisms. Brain stem lesion on MRI may be connected with the pathogenesis of the dispersed-type sleep with special respect to amplitude reduction of sleep-waking circadian rhythm. Circadian rhythm of body temperature (BT) was irregular in amplitude, phase, and period without synchronization with sleep-wakefulness rhythm. Hypothermia was also demonstrated at the basal state, while BT increased when he suffered from respiratory infection. It is likely that hypothermia in our case is caused by the BT shift to the lower side due to malfunction of BT integrating system including preoptic area and anterior hypothalamus.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute Disease↗

Biphasic effect of locally applied apomorphine and 2,3,4,5-tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine on the release of striatal dopamine investigated by means of brain dialysis.

The effects of 3 kinds of dopamine (DA) agonists, apomorphine (APO), 2,3,4,5-tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine (SKF-38393) and quinpirole (QPL), on DA release were examined in the caudate-putamen of the freely moving rat by means of microdialysis during local administration of various concentrations of these DA agonists. Infusion of 10(-4) M and 10(-5) M concentrations of APO and 10(-5) M and 10(-6) M of SKF-38393 induced a brief increase in DA release followed by a marked decrease. This phenomenon was sensitive to tetrodotoxin (10(-6) M) infusion. On the other hand, all the tested doses of QPL, 10(-4) M, 10(-5) M, 10(-6) M and 10(-7) M, reduced DA release without showing transient increase.

2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-ben↗

Accumulation of gangliosides with N-acetylneuraminosyl(alpha 2-6)lactosamine structure in primary human hepatoma.

Gangliosides of hepatomas have been analyzed by using a monoclonal antibody directed to N-acetylneuraminosyl(alpha 2-6)lactoneotetraosylceramide (sialyl(alpha 2-6)paragloboside), which was prepared by injecting the monosialoganglioside fraction of human meconium into BALB/c mice. The monoclonal antibody, named MSG-15, was found to bind sialyl(alpha 2-6)paragloboside, but it failed to react with other gangliosides, including N-acetylneuraminosyl(alpha 2-3)lactoneotetraosylceramide (sialyl (alpha 2-3)paragloboside) and "Ii"-type gangliosides. MSG-15 was found to recognize NeuAc alpha 2-6Gal beta structure of the ganglioside. Gangliosides obtained from human hepatomas were analyzed by immunostaining on high-performance thin-layer chromatography plates using the monoclonal antibody MSG-15. All primary hepatoma samples used in this study (nine samples) were found to contain sialyl(alpha 2-6)paragloboside, which accounted for 13-31% of the monosialoganglioside fractions in the hepatomas. Furthermore, MSG-15 recognized several monosialogangliosides in addition to sialyl(alpha 2-6)paragloboside. These gangliosides apparently also contain a terminal NeuAc alpha 2-6Gal beta structure. Other ganglioside fractions obtained from hepatoma and meconium were immunostained on thin layer chromatography plates with MSG-15. Additionally, another monoclonal antibody (H-11), which recognizes terminal lactosamine structure, was used to immunostain these fractions after sialidase treatment. Bands stained with both monoclonal antibodies showed similar mobilities to each other in the di- and trisialoganglioside fractions as well as monosialoganglioside fraction. In control liver, GM3 ganglioside accounted for 92% of monosialoganglioside fraction, and sialyl(alpha 2-6)paragloboside accounted for less than 1% of the fraction. Immunohistochemical study by using MSG-15 in tissue sections from hepatocellular carcinoma and normal liver tissues demonstrated that only hepatocellular carcinoma cells gave a positive reaction. These results suggest that the biosynthetic pathway of gangliosides containing NeuAc alpha 2-6Gal beta 1-4GlcNAc beta structure is activated in hepatoma cells.

Animals↗

Transtympanic endoscopic findings in patients with otitis media with effusion.

Using a fine, rigid endoscope (Olympus, SES-1711K), we examined the middle ear, including the tympanic orifice of the eustachian tube, of children with otitis media with effusion (OME) in its active stage (26 ears), in the convalescent stage (13 ears), and during treatment with ventilation tubes for 10 days to 6 months (five ears) through myringotomy with the patients under general anesthesia. Several color photographs of representative ears are shown. In the active stage of OME, edema (73.1%) and hyperemia (23.1%) were characteristic features of the middle ear mucosa, and normal mucosa was seen in only one ear (3.1%). The tympanic orifice of the eustachian tube, which could be examined in 12 ears, were stenosed with edema in four ears (33.3%) or plugged with effusion in three ears (25.0%) in this group. In the convalescent stage of OME, dilated vessels were most often seen (69.2%), but the rest of the patients had normal mucosa (30.8%) in the middle ear, and none of them had edema nor hyperemia. The tympanic orifice of the eustachian tube, which could be examined in five ears, was clearly patent in all the patients in this group. One ear that was treated with a ventilation tube for 1 month showed dilated vessels and less severe inflammation than did ears that were in the active stage of OME, and three ears that were treated for more than 3 months showed almost normal middle ear mucosa.

Child↗

Viscosity of effusion in the middle ear and eustachian tube in patients with otitis media with effusion.

The viscosity of middle ear effusion (MEE) in the tympanic cavity and in the bony portion of the eustachian tube (ET) was compared in 11 specimens (10 patients) with otitis media with effusion (OME). Twenty microliters of effusion from the bony portion of the ET was sampled through myringotomy on the anterosuperior quadrant of the tympanic membrane with a micro-syringe with a curved needle. MEE in the hypotympanum was also sampled by separately puncturing the posteroinferior quadrant of the tympanic membrane. Using the microviscometer developed by one of the authors, the relative viscosity of these effusions were measured, and their natural logarithmic values were compared between the two sites mentioned above in each patient by obtaining their ratios (ET/ME). Effusion was found to have a significantly higher viscosity in the bony portion of the ET than in the hypotympanum (paired t-test: t = 3.859, p less than 0.01). In two patients with OME (serous mastoiditis) due to radiation to the temporal region, the ratios of the viscosity were comparatively small. On the other hand, excluding these two patients with serous mastoiditis mentioned above, the ratios were highest in two patients with a history of more than 60 days of hearing loss. These results were considered to be a clue to the possibility that viscous effusion aggravates ET function as a result of OME.

Adult↗

[The development of a highly sensitive IgE immunoradiometric assay using monoclonal antibodies].

We have developed two-site immunoradiometric assay (IRMA) for quantitation of human serum IgE, using two different anti-IgE monoclonal antibodies which recognize different epitopes on IgE molecule. We obtained 25 different monoclonal antibodies classified seven groups, and then two different monoclonal antibodies were selected for bead coater and tracer after checking the titer and specificity of each antibody. IgE IRMA we developed here showed good performance in terms of specificity, sensitivity and reproducibility. No cross-reactivity to IgG, IgM and albumin in the level of normal range was observed. The sensitivity for IgE assay was 0.6 x 10(-3) IU/tube and measurable range was 0.01-20.0 IU/tube (0.5-10(3) IU/ml). Coefficient of variations of Intra assay were 2.2-4.3% and average recovery yield was 92.5-108%. Good correlations with Phadebas IgE PRIST and Pharmacia IgE RIA were obtained i.e., y = 1.12x-0.19 (r = 0.96) and y = 0.97x-5.9 (r = 9.7), respectively. These results indicate that the assay system will contribute much to the routine diagnosis for atopic allergy disease and parasitic infections.

Antibodies, Monoclonal↗

[A clinical study of death in profound mental retardation with motor disturbance].

Among 848 cases of profound mental retardation with motor disturbance admitted to Metropolitan Medical Center of Severely Handicapped in the last 20 years, 98 died. The 94 cases whose cause of death was determined were clinically investigated. There was no difference in sex, and 72% of the patients died before the age of 15 years. Half of the patients died of pneumonia; sudden death occurred in 9, and ileus in 8. These three were thought to be the most important and characteristic causes of death in severely handicapped patients. In recent years, deaths due to pneumonia have decreased and those due to ileus have disappeared, but deaths due to malignant neoplasm have begun to be recognized. There were also some deaths from intracranial hemorrhage in young children, and some deaths from tracheal bleeding in those who had tracheal tubes. These two were also important causes of death in the patients. Sudden death had certain characteristics: most cases were adolescent or young patients with mixed quadriplegia who were sensitive to environmental changes and often showed marked hypertonia by athetosis, and in addition, all of their acute changes occurred between 5 and 8 a.m. or between 6 and 9 p.m.

Adolescent↗

Distribution of neurons with set- and movement-related activity before hand and foot movements in the premotor cortex of rhesus monkeys.

Neuronal activity was studied in the premotor cortex (PM) of two rhesus monkeys, each of which performed both forelimb and hindlimb movements. On each trial, the monkey received a visual instruction stimulus (IS) that indicated whether a foot or a hand movement would be rewarded on that trial. After a delay period, during which the monkey withheld an overt movement, a visual trigger stimulus (TS) was presented to indicate that the monkey should execute a movement. Of 572 task-related neurons recorded in PM, 149 neurons showed set-related activity, defined as a significant increase or decrease in discharge rate throughout most of the instructed delay period, and 299 neurons showed movement-related activity, defined as a significant change in discharge rate between the TS and movement onset. Both set- and movement-related activity were subdivided into three patterns: activity modulation 1) before a foot movement only ("foot" neurons); 2) before a hand movement only ("hand" neurons); and 3) before both foot and hand movements ("mixed" neurons). The distribution of set-related neurons mostly overlapped with that of movement-related neurons, although set-related neurons were located in more restricted regions than movement-related neurons. "Foot" neurons with set- and movement-related activity were distributed near the superior precentral sulcus. "Hand" neurons were mainly located lateral to the "foot" neurons with some overlap. The results indicate that most PM set- and movement-related neurons contribute, respectively, to the preparation for and execution of specific limb movements, as opposed to movement per se. Further, the differential distribution of neurons with activity related to hindlimb vs. forelimb movement supports previous indications that PM is topographically organized.

Animals↗

The asymptotic transectional/circumferential homogeneity of the solutions of reaction-diffusion systems in/on cylinder-like domains.

It is often reported that an animal with spotty coat markings on its body has a tail with stripe-shaped pattern. In other various biological and chemical phenomena in/on cylinder-like domains, longitudinally periodic band patterns are observed much more often than the other non-uniform patterns. This paper mathematically explains these observations by proving that, in/on a long and narrow cylinder-like domain, any solution of reaction-diffusion system asymptotically loses its spatial dependence in the transectional/circumferential direction.

Animals↗

Structural evaluation of glucose analogues on feeding elicitation in rat.

The effects of 12-mumol doses of the glucose analogues glucosamine, 2-fluoroglucose, 2-chloroglucose, 2-deoxyglucose (which were modified at carbon 2 of the glucopyranose ring), 1-aminoglucose and 1-deoxyglucose (modified at carbon 1), on feeding behavior and plasma glucose, insulin, and glycerol were examined after infusion into the rat third cerebroventricle. Plasma glucose and glycerol levels were elevated by glucosamine or 1-aminoglucose. Plasma insulin levels were unchanged by these analogues. Feeding was induced in 62% to 87% of the rats tested after infusion of glucosamine, 2-fluoroglucose, 2-chloroglucose, 2-deoxyglucose, 1-aminoglucose, or 1-deoxyglucose (mean meal size in responding rats, 43.9, 25.8, 22.7, 16.0, 42.3, and 3.8 pellets, respectively). The order of potency to induce feeding was amino, halogen, and hydrogen groups. These data reinforced the concept that the potency of glucose analogues to induce feeding depends on substituents at carbon 1 and carbon 2 of the glucopyranose ring.

Animals↗

Characteristics of psychomotor performance and time cognition in moderately obese patients.

To clarify adherence of obese subjects to external food-relevant stimuli, we examined time cognition and psychomotor functioning of the obese under noneating conditions in the present study. Matched on the basis of age, sex, height, intelligence quotient and education, 13 moderately, but adult-onset obese (mean obesity index +/- SEM, 53.9 +/- 5.0% by Matsuki's method) and 13 normal weight subjects (-6.3 +/- 2.3%) were tested. Obese females were slower than normal weight control subjects in alternate tapping of two metal plates (p less than 0.01) and in transfer of a dowel (p less than 0.05). Normal subjects were slightly but significantly (p less than 0.05) more efficient in a self-cued traverse movement test, whereas the obese subjects were very much less efficient in the self-cued than in the externally-cued test. These findings suggest that evaluation of deficits of the obese must consider other factors in addition to simple physical slowness due to fattening. In time cognition tests, cognitive levels of the obese were more accurate when initiated by time cues than when they were self-cued (p less than 0.01). The results indicate that obese (even after adult-onset) may exhibit impairment in internal time cognition when deprived of external modulating time cues.

Adult↗

Changing concepts of motor areas of the cerebral cortex.

Recent development of studies on cerebral cortex of primates provides evidence that there exist multiple motor representation areas in the frontal lobe. By analyzing the activity of single cells in association with performance of a variety of motor behavior, new concepts on the functional role of each area are developing.

Humans↗