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Biomedical subjects

A Uno

Publications and source records attributed to A Uno.

At least 55 records · Page 3Linked to original sources
PubMed1997

Lipopolysaccharide and interleukin-1beta augmented histidine decarboxylase activity in cultured cells of the rat embryonic brain.

We investigated the effect of lipopolysaccharide (LPS) and various inflammatory cytokines on the histidine decarboxylase (HDC) activity in cultured cells of the rat embryonic brain. Histaminergic neuronal cell bodies were supposed to exist in cultured cells of the diencephalon but not in those of the cortex. The HDC activity was elevated by adding LPS and interleukin-1 beta (IL-1beta) but not by tumor necrosis factor-alpha (TNF-alpha) and IL-6 to the mixed primary cultures of diencephalon. In the adherent cell fraction of the cultured diencephalon cells, HDC activity was also enhanced by LPS and IL-1beta. In a similar manner, LPS augmented HDC activity in the mixed primary culture of cerebral cortical cells and in its adherent cell fraction. The effects of IL-1beta but not LPS in the mixed primary culture of diencephalon were canceled by a prior exposure to cytosine-beta-D-arabinofuranoside. The changes in HDC activity after exposure to LPS for 12 h were not accompanied by increased mRNA levels. In these cell cultures, mast cells were not detected by Alcian Blue staining. These results indicated the presence of the third type of HDC-bearing cell besides neurons and mast cells in the brain. The increase of HDC activity by IL-1beta might be due to cell proliferation.

Animals↗
PubMed1997

Auditory evoked responses under total spinal anesthesia in rats.

In order to investigate the function of the auditory pathway from the cochlea to the brain stem under total spinal anesthesia, the auditory brain stem response (ABR), compound action potential of the cochlear nerve (CAP), and cochlear microphonics (CM) were simultaneously recorded in rats. Total spinal anesthesia was induced by infusion of 2% lidocaine hydrochloride at a constant rate of 0.10 mL/min into the cerebrospinal fluid through the rats' skulls. The ABR completely disappeared within 1.5 to 4 minutes. After cessation of the injection, the ABR reappeared, starting from wave I and progressing through waves II and III to wave IV. The latency change of the CAP throughout the recording period was quite similar to that of wave I of the ABR. A reduction in amplitude of the CM was observed, but the CM did not disappear during the recording period. Disappearance of the ABR was due, not to loss of cochlear function, but to anesthetic effects on the acoustic nerve and the brain stem. Monitoring of the ABR provided information on the level of neural activity in the brain stem under total spinal anesthesia.

Action Potentials↗
PubMed1997

Comparison of interaural time and intensity difference discrimination in patients with temporal lobe lesions.

We studied the sound lateralization in 15 patients with left (12 patients) or bilateral (3 patients) temporal lobe cerebrovascular lesions. The lesions included the auditory cortex. Interaural time difference (ITD) and interaural intensity difference (IID) discriminations were separately measured by using a self-recording apparatus. All 12 patients with left temporal lobe lesions could discriminate ITD, and their IID thresholds were significantly higher than those in healthy volunteers. None of the 3 patients with bilateral temporal lobe lesions could discriminate ITD. On the other hand, all patients with either unilateral or bilateral temporal lobe lesions could discriminate IID and their IID thresholds were significantly higher than those in healthy volunteers. The present findings indicate that the auditory cortex plays an important role in discriminating both cues, but that the role may not be essential for IID.

Auditory Cortex↗
PubMed1997

Single-photon emission CT and MR findings in Klüver-Bucy syndrome after Reye syndrome.

We present the MR and single-photon emission CT findings in a 3-year-old patient in whom Klüver-Bucy syndrome developed after Reye syndrome. MR images showed diffuse brain atrophy, which was predominant in the temporal lobes, and single-photon emission CT scans showed decreased cerebral perfusion in the bilateral temporal lobes and associated cortical areas.

Agnosia↗
PubMed1997

[Developmental dyslexia and dysgraphia--a case report].

We reported a 7-year-old, right-handed boy whose reading and writing of kana and kanji were impaired. He also showed a severe deficit in visuo-spatial perception skills. Nevertheless, his ability to read and write kana characters was facilitated by means of the Japanese Syllabaries. It is generally considered that the Syllabary involve two kinds of language modalities: auditory-verbal and visuo-verbal language systems. In spite of his intact auditory-verbal language system, his visuo-verbal language skills involved in writing kanji were severely impaired. It was suggested that a severe deficit of visuo-spatial perception skills influenced performance of visuo-verbal language systems. Accordingly, we inferred that the patient recalled a kana character by use of the Japanese Syllabaries based on his good auditory-verbal language system, and supposed that his reading and writing disorders were similar to alexia with agraphia in adult patients with angular lesions.

Agraphia↗
PubMed1997

[A semantic-pragmatic learning disabled child who showed a discrepancy between the abilities of verbal and non-verbal comprehension].

A learning disabled (LD) child with disorder of verbal semantic comprehension was reported. This case showed normal ability of non-verbal semantic comprehension. He was not able to understand the meaning of what he read aloud and/or repeated, which he did well. The focus of his brain dysfunction in the left temporal lobe was revealed by SPECT in spite of MRI findings of no particular lesions. Neuropsychological and cognitive-psychological findings were similar to those reported of adult sensory aphasias with localized lesions.

Child↗
PubMed1997

[A child showing memory disorders].

We report a girl with memory disorders. Her memory remained disturbed regardless of input or output modalities. She could recognize items and recall them randomly, but she could not recall them in the correct order. She showed memory impairment with regard to temporal context. We could clearly demonstrate this by cognitive psychological and neuropsychological tests and by analyzing the results of ordinary intelligence tests by input and output modalities. These results suggest that subjects who show memory disorders should undergo further resting to clarify the qualitative aspects of these disorders and the possibility that learning disabilities caused by memory disorders should be considered a specific type of learning disability.

Child↗
PubMed1997

Thioperamide, a histamine H3 receptor antagonist, increases GABA release from the rat hypothalamus.

Using a microdialysis method and a new high performance liquid chromatography (HPLC)-fluorometric method for the detection of gamma-aminobutyric acid (GABA), we investigated the effect of thioperamide, an H3 receptor antagonist, on the GABA content in the dialysate from the anterior hypothalamic area of rats anesthetized with urethane. The addition of thioperamide to the perfusion fluid increased the release of GABA and histamine. Depleting neuronal histamine with alpha-fluoromethylhistidine, a specific inhibitor of histidine decarboxylase, and the administration of immepip, an H3 agonist, had no effect on basal- and thioperamide-induced GABA release. In addition, an infusion of clobenpropit, the most specific H3 receptor antagonist available, did not alter the basal release of GABA. On the other hand, histamine release was decreased by immepip and increased by thioperamide and clobenpropit. Removing Ca2+ from the perfusion fluid did not alter the effect of thioperamide on the GABA release, whereas that on histamine release was abrogated. These results suggest that the effect of thioperamide on GABA release is not mediated by histamine H3 receptors and that thioperamide acts on the transporter to cause an efflux of GABA from neurons and/or glia. Thioperamide is a popular H3 receptor antagonist which has been used applied to many studies. However, results using this compound should be interpreted in consideration of its effects on GABA release.

Animals↗
PubMed1997

Malignant lymphoma of the transverse colon associated with macroglobulinemia.

We present an unusual case of a malignant lymphoma of the transverse colon associated with macroglobulinemia. A 73-yr-old man was incidentally discovered to have high serum gamma-globulin on a regular check-up. Serum immunoquantitation revealed an IgM level of 3490 mg/dl. Kappa-type Bence-Jones protein was positive in the urine. Immunoelectrophoresis identified the abnormal protein as IgM-kappa. After hospitalization an abdominal tumor was detected with barium and CT, identified as a tumor of the transverse colon. Partial resection of the transverse colon was carried out. Histopathologically the tumor were confirmed as small lymphocytic non-Hodgkin lymphoma of B-cell origin, based on the Working Formulation. According to flowcytometric analysis, the tumor cells were positive for IgM-kappa. The lymphoma cells produced monoclonal IgM, giving rise to macroglobulinemia.

Aged↗
PubMed1996

Sound lateralization in patients with lesions including the auditory cortex: comparison of interaural time difference (ITD) discrimination and interaural intensity difference (IID) discrimination.

We examined sound lateralization using dichotic presentation of noises in 15 patients with left unilateral (12 patients) or bilateral (3 patients) temporal lobe lesions, that included the auditory cortex, and evaluated their abilities to discriminate interaural time and intensity difference (ITD, IID) separately. On the ITD discrimination test, discrimination thresholds in patients with left unilateral lesions were significantly higher than those in normal subjects, but all patients with left unilateral lesions could detect ITD. However, none of 3 patients with bilateral lesions could detect ITD. On the IID discrimination test, all patients with either unilateral or bilateral lesions could detect IID. IID discrimination thresholds in these patients were significantly higher than those in normal subjects. The auditory cortex plays an important role in discriminating both cues, but appears to be necessary for discriminating ITD.

Adolescent↗
PubMed1996

Auditory plasticity in cochlear implant patients.

Dynamic range (DR) of cochlear implant electrodes and speech recognition scores (SRS) were chronologically studied in 23 post-lingually deaf subjects over a period of one year. DR significantly increased over one year (ANOVA, p = 0.03). When DR was compared among three groups of electrodes which were located in the inferior, ascending and superior segments of the cochlear basal turn, that in the superior segment showed the largest increase (p = 0.001), followed by those in the ascending and inferior segments. Vowel and consonant recognition scores with auditory cue were best 6 months after operation and were maintained at the level for one year. Although the time course of improvement differed between DR and SRS, a significant positive correlation was observed at 12 months after operation. Improvement of SRS could be a result of a DR increase in the superior segment of the cochlea, which should convey pitch information over the mid-frequency region.

Adolescent↗
PubMed1996

[A specific disorder in Kanji writing in a learning disabled child with a visual cognition disorder--a cognitive-neuropsychological and electrophysiological analysis].

We reported a learning disabled child with a specific disorder involving Kanji writing. The patient was a 13-year-old boy. Although he manifested generally normal intellectual ability and his performance on WISC-R indicated that VIQ was 101 and PIQ 84, he could only write approximately 20% of Kanji, which he learned at age 6 to 7. On cognitive-psychological tests, he showed a visual cognition disorder that was different from that in a previously reported case during information processing. Electrophysiologically, he showed a disorder in visual task-relevant potentials. The mechanism underlying this patient appears to be a retrieval disorder for complex graphic forms in addition to a visual cognition disorder because of two reasons. One is that he could distinguish Kanji from similar graphic forms. The other is that he could read Kanji aloud.

Adolescent↗
PubMed1996

[Auditory perception in patients with multiple and severe handicaps: study of mismatch negativity to speech sounds].

We have found that the mismatch negativity (MMN) of event-related potentials (ERPs) to the tone burst sound is generated passively in some multiple and severe handicapped patients. This study investigated whether 10 patients with severe handicaps, whose auditory perception is hard to be evaluated clinically, exhibited MMN to the speech sound (SS). The stimuli included tone bursts of 700 and 1000 Hz in frequency, and 4 patterns of SS (1 phoneme: [a, ae], [a, o]; and 2 phonemes: [amo, ano], [ao, aka]) presented at an 85: 15 occurrence with 75 dBSPL. In the tone burst paradigm, 7 patients had a definite MMN wave followed by an N1 wave. However, a few patients showed MMN to some patterns of SS. The latency of MMN to SS was almost within normal limits. These results suggest that these patients could discriminate subtle differences of frequency in some speech sounds, although their auditory response to actual speech sounds were poor.

Adolescent↗
PubMed1995

[A specific disorder of Kanji writing observed in a learning-disabled child--cognitive-psychological and neuropsychological analysis].

We reported a learning-disabled child who demonstrated a specific disorder of Kanji writing. A right-handed 13-year-old boy had showed no abnormality in general intelligence (VIQ114 and PIQ 100 in WISC-R), but could write only 35% of Kanji, which he should have learned six years before. It was necessary to develop a new test battery to detect the symptom which had not been detected using current existing test batteries. In cognitive-psychology, this patient had a retrieval disorder of graphic forms of Kanji. In addition, he showed a disorder in reproduction of complex graphic forms which he was asked to remember. Therefore, it is likely that he had a disorder for both Kanji and complex graphic forms, which is similar to the syndrome of pure agraphia of Kanji in adults.

Adolescent↗
PubMed1995

Neuropharmacological mechanisms of emesis. I. Effects of antiemetic drugs on motion- and apomorphine-induced pica in rats.

The effects of diphenhydramine, domperidone, ondansetron, and diphenidol on motion- and apomorphine-induced pica (i.e., kaolin ingestion) in rats as the measure analogous to emesis in other species were examined. Diphenhydramine (10 and 20 mg/kg) and diphenidol (30 mg/kg) inhibited kaolin intake induced by 60-min double rotation, while domperidone and ondansetron did not. Kaolin intake induced by apomorphine (10 mg/kg) was inhibited by domperidone (2 mg/kg) and diphenidol (30 mg/kg), but not by diphenhydramine or ondansetron. These findings suggest that the emetic pathways through the inner ear (double rotation) and the chemoreceptor trigger zone (apomorphine) are pharmacologically independent and are mediated by histamine H1 receptors and dopamine D2 receptors, respectively. Diphenidol may inhibit a common locus of emesis.

Animals↗
PubMed1995

Neuropharmacological mechanisms of emesis. II. Effects of antiemetic drugs on cisplatin-induced pica in rats.

The effects of diphenhydramine, domperidone, ondansetron, and diphenidol on cisplatin-induced pica (i.e., kaolin ingestion) in rats as the measure analogous to emesis in other species were examined. Ondansetron (2 mg/kg) and diphenidol (30 mg/kg) inhibited kaolin intake induced by cisplatin (10 mg/kg), but diphenhydramine and domperidone did not. Diphenhydramine and diphenidol have been shown to inhibit kaolin intake induced by double rotation, while domperidone and ondansetron did not, and kaolin intake induced by apomorphine was inhibited by domperidone and diphenidol, but not by diphenhydramine or ondansetron. These observations, together with the present findings, suggest that the emetic pathways through the inner ear (double rotation), chemoreceptor trigger zone (apomorphine) and visceral afferent (cisplatin), are pharmacologically independent and are mediated by histamine H1 receptors, dopamine D2 receptors and serotonin 5-HT3 receptors, respectively. It is conceivable that diphenidol may inhibit the emetic center itself, although the receptor on which it acts is not known.

Animal Feed↗