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Biomedical subjects

T Taira

Publications and source records attributed to T Taira.

At least 163 records · Page 9Linked to original sources
PubMed1988

Genetics of an unstable white mutant in Drosophila simulans: reversion, suppression and somatic instability.

A spontaneous white mutation, white-milky (wmky) of Drosophila simulans is moderately unstable and is associated with a 16-kb long DNA insertion into the white gene. wmky, which is an unstable mutation found in D. simulans, has been genetically analyzed. Among nine spontaneous, partial reversions toward wild type, five were white locus mutations. They are phenotypically different from each other and three show eye color sexual dimorphism indicating a failure of the dosage compensation mechanism. Two w locus mutations whose eye color appeared identical between males and females were also isolated. Of the other back-mutants, three were associated with a recessive suppressor of wmky and one was a semidominant suppressor. These suppressor loci are located on the third chromosome at map positions about 90 and 120, respectively. The suppressor mutations demonstrate specific effects on w locus mutations derived from wmky which lack in the gene dosage compensation. Somatic instability was detected at the frequency of 5.6 X 10(-4) in wmky flies heterozygous for the recessive suppressor and the frequency was increased 10-fold when the suppressor mutation was placed in a different genetic background.

Alleles↗
PubMed1988

Neonatal treatment with monoamine uptake inhibitors alters later response in behavioural 'despair' test to beta and GABA-B receptor agonists.

The administration of monoamine uptake-inhibiting antidepressant drugs to rats during the early postnatal period was previously shown to lengthen the duration of subsequent immobility in Porsolt's swim test, hence suggesting increased behavioural 'despair' in these animals. Because the mechanism of the antidepressant action may be related to changes in the cerebral monoamine or gamma-aminobutyric acid (GABA) function, the present study was carried out to examine the response in the swim test to a beta-receptor agonist salbutamol, or to the GABA-B receptor agonists progabide and baclofen in rats treated with antidepressant drugs during the second and third postnatal week: either desipramine 5 mg/kg, nomifensine 10 mg/kg or zimeldine 25 mg/kg. When tested a month later i.e. at the age of two months these rats were immobile in water for a longer period than the controls. Salbutamol 10 mg/kg and progabide 100 mg/kg increased the immobility time in the control rats but neither drug affected the rats treated with desipramine, nomifensine or zimeldine. When the animals were 5 months of age, salbutamol 10 mg/kg and baclofen 10 mg/kg shortened the immobility time in the desipramine-treated rats. The control rats and those treated with zimeldine were not affected by the drugs. The results indicate that in the rats which were neonatally treated with antidepressants, the immobility time in water is lengthened in adulthood. Moreover, the response to beta-receptor and GABA-B receptor agonists is increased from the response observed in the control rats.

Albuterol↗
PubMed1988

Early postnatal deprivation of active sleep with desipramine or zimeldine impairs later behavioural reactivity to auditory stimuli in rats.

To examine the functional significance of early postnatal active sleep for the development of behavioural reactivity to auditory stimuli, rat pups were daily injected i.p. from the 7th to the 18th postnatal days with 5 mg kg-1 (6.6 mmol l-1) desipramine or 25 mg kg-1 (12.2 mmol l-1) zimeldine. Sleep-wake behaviour was recorded with a static-charge-sensitive bed (SCSB) method. Both desipramine and zimeldine suppressed the percentage of active sleep relative to the total recording time throughout the treatment period. In addition, these drugs increased the percentage of quiet state and waking. At the age of 38 days the zimeldine-treated rats showed more motor activity in the open field than the controls. At the age of 39 and 78 days all rat groups behaved similarly in the open field. Startle measures and motor activation, provoked by auditory stimulation, were determined by the SCSB method when the rats were 4 months of age. Auditory stimuli, consisting of a series of ten clicks, induced a greater number of startles as well as strong movement responses in the control rats than in the desipramine- or zimeldine-treated rats. The number of small movement responses did not differ between the rat groups. These findings indicate that early postnatal active sleep and the monoaminergic systems regulating it may be important for the normal development of neuronal circuitry associated with later reactivity to auditory stimuli.

Acoustic Stimulation↗
PubMed1988

Functionally polarized layers formed by epidermal cells on a permeable transparent collagen film.

Rat epidermal cells were cultured on a transparent collagen film, which was permeable to low Mr substances. Then the cells were bathed in both media (apical and basal), which were separated by the collagen membrane. The cells formed a multi-layered epidermal sheet with well-developed structures of desmosomes. This sheet on a permeable support was found to be an effective permeability barrier for glucose and amino acids. The epidermal layer showed functional polarity for the uptake and excretion of nutrients, metabolites and newly synthesized proteins: glucose and amino acids were taken up exclusively from the basal medium and lactate was secreted selectively into the same medium, whereas ammonia was secreted into the apical medium. The apical media became more acidic than the basal ones, presumably due to the preferential distribution of H+ transport systems on the apical side of the epidermal layer. The epidermal cells that expressed functional polarities in vitro as described above were able to proliferate and differentiate, and remained healthy for as long as at least 40 days even using a conventional culture medium with foetal calf serum, but without any special growth factors and feeder cells.

Amino Acids↗
PubMed1988

[Identification of location of electrode tip during percutaneous retrogasserian glycerol injection (PRGI) with blink reflexes elicited by direct stimulation of trigeminal complex (DBR)].

In order to identify the location of the electrode tip during percutaneous retrogasserian glycerol injection (PRGI), the blink reflex (DBR) following direct stimulation of the trigeminal complex (the gasserian ganglion, trigeminal rootlets, or the 3rd division of the trigeminal nerve) was obtained from 6 patients with trigeminal neuralgia. 1) The waveform of the DBR was very similar to that of the blink reflex (BR) elicited by percutaneous stimulation of the 1st division of the trigeminal nerve. However, the latency of early reflex (R1) as well as late reflex (R2) of the DBR was approximately 2 msec shorter than that of the conventional BR. 2) When the electrode tip was introduced into the gasserian ganglion, the DBR showed the largest response under the same recording condition, whereas the DBR was not recorded when the tip of the electrode was placed into either the arachnoid space or the subdural space. The each DBR response, however, showed the same configuration when the electrode tip was situated at the territory of the 1st, 2nd or 3rd division of the trigeminal nerve within the gasserian ganglion or the trigeminal cistern. 3) The DBR always appeared under the anesthesia with the intravenous administration of 10 mg diazepam and 30 mg pentazocine. 4) Based on the present study, the DBR proved to be an usuful parameter in determining whether the electrode tip is introduced into the trigeminal complex or not, particularly in the case of patients having no reliable sensory response to electrical stimulation.

Aged↗
PubMed1987

Surgical treatment of hypertensive intracerebral haematoma by CT-guided stereotactic surgery.

Ninety consecutive cases of hypertensive intracerebral haematoma were treated with CT guided stereotactic evacuation. The patients were composed of 61 males and 29 females, ranging from 42 to 87 years old. The location of haematoma was either in the putamen (59 cases) or in the thalamus (31 cases). The average volume of the evacuated haematoma was 21.4 ml in the putaminal haematoma and 14.0 ml in the thalamic haematoma. Postoperative follow-up study in 46 patients showed good recovery of neurological deficits both in putaminal and thalamic group. Criteria of surgical indication of CT-guided stereotactic evaluation of intracerebral haematoma were advocated based on the author's clinical experience.

Adult↗
PubMed1987

Short latency somatosensory-evoked potentials--direct recording from the human midbrain and thalamus.

Short latency somatosensory-evoked potentials were recorded from the human thalamus and the midbrain during stereotactic operations. Several subcomponents were recognized on the peak of N18. These were recorded with maximal amplitude at the border between the caudal portion of the thalamus and the rostral midbrain. Two positive-negative responses, not previously shown, were observed between P14 and N18. These responses were prominent in the rostral midbrain. These findings indicate that the ascending phase of N18, and the N18 itself, are the compound potential generated in the mesodiencephalic junction.

Brain Mapping↗
PubMed1987

In vitro maturation of collagen fibrils modulates spreading, DNA synthesis, and collagenolysis of epidermal cells and fibroblasts.

Collagen fibrils were maturated in vitro by incubating them in a serum-containing culture medium at 37 degrees C for varied lengths of time. Epidermal cells and fibroblasts were cultured on these maturated collagen gels to see the effects of maturation on cellular morphology and physiology. The spreading and DNA synthesis of both types of cells on the maturated collagen gels were significantly enhanced compared to those on fresh gels. The maturation did not affect the cellular adhesiveness to the substrate. The secretion of collagenase by epidermal cells was suppressed on the maturated collagen gels, the extent of the suppression being related to the length of maturation of the gels. These maturation-related effects of collagen were also observed when collagen was incubated in the medium without serum, indicating that the effects are not due to deposition of serum proteins to collagen gels during maturation. Physical and chemical characterizations of the maturated collagen were performed: the mechanical strength of collagen gels increased in maturated collagen gels, the amounts of insoluble collagen increased with the maturation. These changes in the chemical and physical nature of the maturated collagen gel strongly suggested that there was an increase in intermolecular crosslinks during the process of maturation. These maturation-induced changes in collagen were marked when collagen gels were incubated in the presence of glucose, indicating that a glucose-protein reaction such as the Maillard reaction is involved in this phenomenon.

Animals↗
PubMed1987

Isolation and genetic analysis of operator-constitutive mutants of the H1 operon in Salmonella typhimurium.

In phase-2 cells of diphasic Salmonella strains, expression of H1 is repressor, coded for by the rh1 gene. A procedure for the isolation of operator-constitutive (H1-Oc) mutants of the H1 operon is described. Using three-factor crosses between an H1-Oc H1 strain and H1-O+ H1 strains, where motility recovery via H1-phase (or phase 1) flagellation was used as the selected marker and the H1-O character was the unselected marker, the relative position of the H1-Oc site to the H1 gene was determined. A diphasic H1-Oc strain produced, in phase 2, copolymer filaments composed of H1 and H2 flagellin.

Flagella↗
PubMed1987

[Intracerebral granuloma with serum anti-human ascaris antibody: case report].

A 1.5-year-old girl with a convulsion attack due to intracerebral granuloma in the right frontal lobe is reported. Her serum was positive with anti-human ascaris antibody, although no ova of the parasites were detected in the feces. She had grown up intimately with several cats in the home. These findings suggested that the granuloma was due to larva migrans of toxocara, which cross-reacts immunologically with human ascaris. Histological examination of the granuloma revealed no eosinophilic infiltration. No systemic reactions such as eosinophilia and hepatomegaly were found except for elevation of protein in cerebrospinal fluid. These were similar to those of ocular type of toxocara larva migrans.

Animals↗
PubMed1987

[CT-guided stereotactic brachytherapy in deep-seated malignant gliomas--interstitial irradiation by double-catheter after-loading method].

CT-guided stereotactic brachytherapy has been performed for the deep-seated malignant gliomas using the double-catheter after-loading method. The catheter system consists of two coaxial polyethylene tubes with closed tips. The outer catheter is 3.0 mm in outer diameter and 2.4 mm in inner diameter. The inner catheter is 2.0 mm in outside diameter and 1.4 mm in inside diameter, and contains the radioactive sources. Localization of the target volume is determined by the preoperative findings of computed tomography (CT), magnetic resonance imaging (MRI), and cerebral angiography. Dosimetry and dose planning are so finalized for the target volume as to be irradiated interstitially more than tumoricidal dose. After stereotactic biopsy of the deep-seated brain tumors, stereotactic implantation of the outer catheters is performed using Iseki Stereotactic System in the CT room. Burr holes had been previously opened in the operating room. The inner catheters containing nonradioactive sources (dummy sources) are inserted, and skull X-p is taken to confirm the position of the dummy sources, and to calculate the dosimetry by computer. The inner catheters are replaced with catheters containing radioactive sources (226Ra) in the irradiation room. 226Ra sources deliver at least 500 rads/day (approximately 20 rads/hr) to the target volume as interstitial irradiation. Two patients of malignant gliomas treated with this procedure were shown as representative cases. These patients underwent CT-guided stereotactic brachytherapy as "boost" combined with conventional external irradiation.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1987

[EEG topographic changes of brain abscesses in children].

EEG topography was investigated before and after surgical treatment in 4 patients with brain abscess aged from 5 to 13 years. According to the recording technique designed by Matsuoka and Ueno, the recorded EEG for each 5 seconds was analyzed to obtain square roots of power spectra for each band of delta (2-3.8 Hz), theta (4-7.8 Hz) and alpha (8-12.8 Hz) which were then added for the 60-seconds duration of each trial. After that, numerical matrix presenting the topographic distribution of spectral energy of each band were constructed and displayed as color images. In addition, the EEG topographies of brain abscesses were compared with the CT scans simultaneously obtained. In all of four cases before surgical treatment of the brain abscess, the location of the focal delta wave on the EEG topography was more closely related to the site of brain abscess comparing with its correlation between the location of the delta focus on the conventional EEG and the site of brain abscess. In contrast, as for the theta wave, there was no prominent correlation to the site of the brain abscess. In the early stage of 10-15 days after aspiration of the brain abscess, the most characteristic change of the EEG topography was an approximately 25% reduction of the maximum equivalent voltage of delta band with associated disappearance of the sharply located focal delta wave being noted before aspiration.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1986

Neurilemmoma of the larynx: (a case report).

The authors have treated a 61-year-old woman with neurilemmoma of the larynx. The tumour was located in the submucosal region of the arytenoid on the right side of the larynx. Surgical resection of the tumour had to be done by external neck excision instead of endoscopically.

Female↗
PubMed1986

Surgical techniques for a deep concha, a pseudomeatus, and high projection in congenital microtia.

Some modified surgical techniques are described for constructing a deep conchal cavity and pseudomeatus and obtaining high auricular projection in congenital microtia. At the primary operation, a rather small portion of the microtic vestige is utilized for the lobule by switching, sparing the skin for the concha, with no free skin graft used. For higher projection of the auricle, three-dimensional transposition of a retroinfraauricular flap together with cartilage pieces underneath is applied to the cephaloauricular sulcus. A deep conchal cavity is constructed by further removal of the soft tissue there, transplantation of a cartilage for building a high posterior wall of the concha. The external meatus is successfully imitated by transplantation of a cone-shaped composite graft taken from the cymba of the opposite ear. The retroinfraauricular flap, the reconstruction of a deep concha, and the composite graft technique were successfully used in 55, 16, and 11 ears, respectively.

Cartilage↗
PubMed1986

Long-term follow-up study of rostral mesencephalic reticulotomy for pain relief--report of 34 cases.

A long-term follow-up study of rostral mesencephalic reticulotomy (RMR) for pain relief is presented. 34 patients (24 males and 10 females) were operated. Ages ranged from 18 to 65 years. The follow-up period was 1-70 months. The overall effectiveness of RMR showed good relief of pain in 23 patients (67%). The study of effectiveness of RMR according to type of pain showed good relief of pain in 5 out of 6 patients (83%) with nondenervation pain, whereas satisfactory pain relief was obtained in 18 out of 28 patients (64%) with denervation pain.

Adolescent↗