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K Sasamoto

Publications and source records attributed to K Sasamoto.

At least 37 records · Page 2Linked to original sources
PubMed1993

Appearance of calretinin-immunoreactive neurons in the upper layers of the rat superior colliculus after eye enucleation.

The effects of retinal deafferentation on a calcium-binding protein, calretinin, in the upper layers (superficial gray layer and optic nerve layer) of the rat superior colliculus were examined. In intact rats and on the ipsilateral side of unilaterally eye-enucleated rats, the superficial gray layer and optic nerve layer contained a few dispersed calretinin-immunoreactive cells. On the contralateral side to the enucleation, the number of immunostained cells in the superficial gray layer and optic nerve layer was increased. These findings suggest that retinal deafferentation results in an increase in contents of calretinin in some cell bodies within the upper layers of the superior colliculus.

Afferent Pathways↗
PubMed1993

Antagonistic action of imidazolineoxyl N-oxides against endothelium-derived relaxing factor/.NO through a radical reaction.

A labile inorganic free radical, nitric oxide (.NO), is produced by nitric oxide synthase from the substrate L-arginine in various cells and tissues. It acts as an endothelium-derived relaxing factor (EDRF) or as a neurotransmitter in vivo. We investigated the reactivity of stable radical compounds, imidazolineoxyl N-oxides such as 2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl 3-oxide (PTIO), carboxy-PTIO, and carboxymethoxy-PTIO against .NO/EDRF in both chemical and biological systems. By using electron spin resonance (ESR) spectroscopy, imidazolineoxyl N-oxides were found to react with .NO in a stoichiometric manner (PTIO/.NO = 1.0) in a neutral solution (sodium phosphate buffer, pH 7.4) with rate constants of approximately 10(4) M-1 s-1, resulting in the generation of NO2-/NO3- and imidazolineoxyls such as 2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl (PTI), carboxy-PTI, or carboxymethoxy-PTI. Furthermore, the effects of imidazolineoxyl N-oxides on acetylcholine- or ATP-induced relaxation of the smooth muscle of rabbit aorta were tested. The vasorelaxations were inhibited by all three imidazolineoxyl N-oxides markedly. The inhibitory effects of carboxy-PTIO was almost 2-fold stronger than those of .NO synthesis inhibitors, N omega-nitro-L-arginine and N omega-monomethyl-L-arginine. Generation of EDRF/.NO was identified by reacting the PTIO in aortic strips and quantitating the reaction product with ESR spectroscopy. Thus, it was clarified that imidazolineoxyl N-oxide antagonize EDRF/.NO via a unique radical-radical reaction with .NO.

Acetylcholine↗
PubMed1993

[Specific IgE antibody titers to hen's egg white lysozyme in allergic children to egg].

Hen's egg white lysozyme (HEL) is one of the minor allergen in hen's egg white. HEL is commonly used to treat disease of respiratory tract, because it have the effect to dissolve mucopolysaccharide and anti-inflammatory action. We examined specific IgE antibody titers (IgE-HEL) in patients with egg allergy and allergic patients to other antigen than egg. Results indicated that 16.37 +/- 29.56 (PRU/ml) (mean +/- SD) of IgE-HEL was found in 30 out of the 39 allergic patients to egg, and 23 (66.7%) out of the 39 patients studied showed RAST scores of more than 2. On the other hand, 1.08 +/- 0.92 (PRU/ml) of IgE-HEL in 12 out of the 44 allergic patients to other antigen than egg, and 5 (11.4%) out of the 44 patients studied showed RAST scores of more than 2. Moreover, we treated a patient who developed anaphylaxis after taking HEL. 1.0 (PRU/ml) of HEL-IgE was found in this patient. These results suggest that we should be careful in treating allergic patients with HEL.

Adolescent↗
PubMed1991

Chemiluminescence assay of N-acetyl-beta-D-glucosaminidase in urine using o-aminophthalylhydrazido-N-acetyl-beta-D-glucosaminide.

The chemiluminescence assay of urinary N-acetyl-beta-D-glucosaminidase using o-aminophthalylhydrazido-N-acetyl-beta-D-glucosaminide as the substrate was examined. Under optimized conditions, a linear chemiluminescence response to the standard N-acetyl-beta-D-glucosaminidase (NAGase) of different concentrations was observed with a correlation coefficient of 0.999 over the range of 0.3 to 20 I.U./l. The present method was compared with the prevalent method using p-nitrophenyl-N-acetyl-beta-D-glucosaminide in the assay of 20 urine samples from healthy subjects, and the correlation coefficient of 0.891 was obtained.

Acetylglucosamine↗
PubMed1990

Projections of two separate cortical areas for rhythmical jaw movements in the rat.

The cortico-bulbar projection from two separate cortical areas which induce different types of rhythmical jaw movements (RJM), and the relationship between these cortical areas were studied with horseradish peroxidase tracing method. One area (A-area) corresponded to the primary jaw motor area and the other (P-area) was located in the agranular insular cortex. Separate descending pathways from two areas passed through the pyramidal tract and projected to the supratrigeminal nucleus, the intertrigeminal region, the dorsal part of the trigeminal sensory complex, and the reticular formation. In the reticular formation, the A-area projected more medially than the P-area did, and the ipsilateral projection from the P-area was more prominent than that from the A-area, although contralateral projections were dominant in the majority of regions. The two areas had only a sparse reciprocal connection. We suppose that the difference in patterns of RJM induced by the two cortical RJM areas may be due to the different projection patterns from these two areas.

Animals↗
PubMed1990

Effects of a medicinal herbal liqueur, "yomeishu", on post-operative gynecological patients.

We administered 20 ml of Yomeishu (YMS) twice a day before meals for 12 weeks to 50 post-operative patients in gynecology and then inquired into their subjective 20 symptoms (sense of fatigue, insomnia, headache and heavy headedness, appetite, stomach-ache, abdominal inflation, vertigo, lumbago, etc.) The YMS group showed a significant improvement on 14 items compared with the control group. On the whole, a great improvement was observed in the YMS group with serious subjective symptoms as well, and there were significant differences for general condition, sense of fatigue, and coldness in extremities.

Alcoholic Beverages↗
PubMed1990

A chemiluminogenic substrate for N-acetyl-beta-D-glucosaminidase, o-aminophthalylhydrazido-N-acetyl-beta-D-glucosaminide.

A new type of chemiluminogenic substrate for N-acetyl-beta-D-glucosaminidase, o-aminophthalylhydrazido-N-acetyl-beta-D-glucosaminide, was prepared by incorporating an enzyme-removable substituent, N-acetyl-D-glucosaminide group, into the hydrazide moiety of luminol. This substrate releases luminol upon enzymatic hydrolysis. The enzyme was detected chemiluminescently using this substrate.

Acetylglucosamine↗
PubMed1990

Two types of rhythmical jaw movements evoked by stimulation of the rat cortex.

Two different patterns of rhythmical jaw movements (RJM) resembling masticatory movements were evoked by stimulation of the cerebral cortex in the rat. The first type of RJM was evoked from the primary jaw motor area, and it always began with a sustained jaw-opening and consisted of high frequency (5-7 Hz) simple opening-closing movements of the jaw. The anterior digastric electromyographic (EMG) activity showed discharges apparently time-locked to each stimulus pulse. The second type of RJM was evoked from the ventral part of the insular cortex. In contrast to the first type of RJM, the second type started with a jaw closing movement in many cases. This type of RJM had large and complex lateral and sagittal movements and the frequency of RJM was low (3-4 Hz). The digastric EMG activity did not show the stimulus-locked component. The pattern of these RJM did not depend on the intensity or frequency of stimulation, but on the site stimulated. These two cortical RJM areas appeared to work independently from each other, because ablation of one area did not affect the pattern of the RJM evoked from the other cortical area.

Animals↗
PubMed1990

A multipurpose dye laser photocoagulation system.

We modified a single argon/dye laser photocoagulator by adding two optical fibers so that it could be used with a slit-lamp microscope, an operating microscope, and with an endophotocoagulation probe. One fiber is attached to a nearby slit-lamp microscope; the other extends approximately 70 m and can be connected to either an operating microscope or an endophotocoagulation probe. An electrically-operated mirror inside the machine controls which of the two fibers the laser beam passes through. Separate control boxes for each fiber permit direct regulation of the photocoagulation process in all situations.

Argon↗
PubMed1988

Studies on the chromosome by scanning electron microscope--a new trial with long-term Giemsa staining.

Chromosomes, which can be seen under a light microscope (LM) as bands, are too thin to see with a scanning electron microscope (SEM). We noticed that chromosomes increase in thickness with Giemsa staining, so that scanning microscopic specimens could be prepared by long-time Giemsa staining for SEM observation, and in the present study the following results were obtained. 1) When the duration of the trypsin treatment was kept constant, and the Giemsa staining was performed from 30-min to 24-h, it was found that the thickness of the chromosomes increased with the length of treatment time, and the fibrous structures were clearly seen. 2) While a sufficient thickness of the chromosomes was obtained with the long-time Giemsa staining, the bands became unclear as the time of staining was extended. 3) A long-time Giemsa staining without trypsin treatment showed more "highly packed" fibers, so that the trypsin treatment was felt to be related to the dispersion of the fibers.

Azure Stains↗
PubMed1987

Prenatal diagnosis of partial trisomy 22 derived from a maternal t(11; 22) (q23; q11).

A fetus with partial trisomy 22 was detected by amniocentesis in a pregnant woman with balanced translocation, 46, XX, t(11; 22) (q23; q11). The aborted fetus had multiple congenital anomalies consisting of microcephaly, cleft lip and palate. The extra acrocentric chromosome was identified as der (22), t(11; 22) (q23; q11). The aborted fetus is compared with other trisomic cases described in literatures, and perinatal diagnosis of this case was discussed.

Adult↗
PubMed1986

Modulation of transmission in rostral trigeminal sensory nuclei during chewing.

Eighty-one sensory neurons in the rostral trigeminal sensory nuclei (main sensory nucleus, nucleus oralis, and the lateral border zone of the motor nucleus) were recorded in urethan-anesthetized rabbits before and during mastication. Receptive-field characteristics were described, and responses evoked by electrical stimulation of the inferior alveolar and infraorbital nerves, sensorimotor cortex, and thalamus were recorded. Forty-four percent of neurons were stimulated by the movements of mastication; nevertheless, evidence is presented that the excitability of the 49 neurons that receive low-threshold mechanoreceptor inputs is depressed during mastication for the following reasons: The spontaneous activity of seven cells was inhibited during movement. The probability of firing in response to stimulation of the peripheral nerve on sensorimotor cortex was decreased during mastication. There was usually a corresponding increase in the latency of the action potentials. Injections of local anesthetic (prilocaine hydrochloride, 4%) into the receptive field of the neuron did not prevent the decrease in excitability during mastication. Fourteen neurons that received inputs from periodontal pressoreceptors were recorded medial to most of the low-threshold group. The excitability of six of these was reduced during jaw closure and during the occlusal phase of movement, that is, within the period in which they would be activated by pressure on the teeth. The rest were tonically suppressed. Eighteen neurons recorded in the lateral border zone of the motor nucleus had receptive fields that were of high threshold or were undefined. They responded to stimulation of the peripheral nerve at high threshold. The excitability of most of these neurons was strongly phase modulated during mastication. They were most excitable during jaw closure or during the occlusal phase of movement and inexcitable during opening. The excitability of the others was tonically depressed. In most cases, the changes in excitability described did not seem to be due to the patterns of activity of the neurons that were generated by the movements. We conclude that the pattern elaborated by the central pattern generator includes selective modifications of sensory transmission. One reason for this is to suppress reflex responses to low-threshold inputs while maintaining the protective response to tissue damage.

Alveolar Process↗
PubMed1986

Spontaneous and MMC induced SCE in lymphocytes from patients with cervical cancer.

The frequencies of spontaneous and mitomycin C (MMC) induced sister chromatid exchanges (SCEs) were investigated in lymphocytes of the peripheral blood of women in different stages (O-III) of cervical cancer. Average generation time (AGT) was also examined by the replicative index (R.I.) method. The following results were obtained: The spontaneous SCE frequency was found to be significantly higher in the cancer group than in the control group; 8.21 +/- 1.42 (mean +/- S.D.) against 5.62 +/- 0.55. The SCE frequency gradually increased with the progression of the cervical cancer. The SCE frequency in patients with carcinoma in situ (CIS), the lowest stage of cervical cancer, was significantly higher than that of the controls. The frequency of MMC induced SCE was higher than that of spontaneous SCE in all groups, and the difference in frequency between MMC induced and spontaneous SCEs of cervical cancer group of the stages I-III was significant by different from that of the control group. The AGT of the cervical cancer group was shorter than that of the control group, but it was not statistically significant.

DNA Damage↗
PubMed1984

Analysis of rhythmical jaw movements produced by electrical stimulation of motor-sensory cortex of rabbits.

The anterolateral regions of the cerebral cortex of rabbits anesthetized with urethan were stimulated with either short trains of electrical pulses at high-frequency (3 pulses, 500 Hz) or 10-s trains of shocks at 50 Hz. The movements of the mandible and the electromyographic (EMG) activity from the muscles of mastication were recorded on magnetic tape and later analyzed by computer. Two basic types of responses are reported: twitches of the digastric muscles that followed the stimulus at short-latency (4-6.7 ms) and rhythmical masticatory movements that could only be evoked by prolonged stimulation. The cortical representations of the short-latency twitch contractions and mastication overlap. Different masticatory patterns are represented in separate areas of the cortex. The movements represented in the anteromedial half of the masticatory area are made mainly in the vertical plane, whereas stimulation of the posterolateral part produces movements in which the jaw swings to the contralateral side during closure. Increases in stimulus intensity usually increase the frequency of the movements, but other changes in the pattern depend on the site of stimulation. The rhythmical bursts of EMG activity often contain stimulus-bound short-latency responses but, since these are not always present, we conclude that they are not essential components of the masticatory pattern. We suggest that the basic patterns of mastication are elaborated by brain stem circuits that are themselves controlled by specific regions of the motor-sensory cortex.

Animals↗
PubMed1984

Corneal endothelial changes caused by ophthalmic drugs.

Morphological changes were examined in the corneal endothelium of rabbits after administration of several drugs widely used in ophthalmology. After administration of epinephrine and dipivalyl epinephrine eye drops, swelling of corneal endothelial cells developed; however, these changes were reversible. No pathological changes were observed in the corneal endothelial layer following the administration of timolol, betamethasone, and gentamicin eye drops. Morphological changes were observed in the corneal endothelial layer after the subconjunctival injection of timolol, betamethasone, and gentamicin.

Animals↗
PubMed1982

Amygdaloid-induced jaw opening and facilitation or inhibition of the trigeminal motoneurons in the rat.

1. Repetitive stimulation of the rat'se central amygdaloid (CAm) nucleus induced rhythmic masticatory jaw movements or continuous jaw opening. Both types of jaw movements were accompanied by coincidental activities of the mylohyoid (Myl) nerve. 2. The effects of CAm stimulation were examined on activities of bilateral Myl and masseteric (Mass) nerves or their motoneurons (Myl-Dig and Mass, respectively). 3. CAm stimulation induced contralaterally dominant facilitation of the Myl nerve activity as well as Myl-Dig motoneurons. These facilitatory effects were caused by EPSPs seen in Myl-Dig motoneurons. 4. One third of the Mass motoneurons were inhibited or hyperpolarized by contralateral CAm stimulation, while a few were facilitated and the majority unaffected.

Action Potentials↗