Hokkaido University Collection of Scholarly and Academic Papers
(65.354 recursos)
HUSCAP (Hokkaido University Collection of Scholarly and Academic Papers) contains peer-reviewed journal articles, proceedings, educational resources and any kind of scholarly works of Hokkaido University.
Mostrando recursos 1 - 20 de 23
1.
5-HT1A receptor agonist affects fear conditioning through stimulations of the postsynaptic 5-HT1A receptors in the hippocampus and amygdala - Li, XiaoBai; Inoue, Takeshi; Abekawa, Tomohiro; Weng, ShiMin; Nakagawa, Shin; Izumi, Takeshi; Koyama, Tsukasa
Evidence from preclinical and clinical studies has shown that 5-HT1A receptor
agonists have anxiolytic actions. The anxiolytic actions of 5-HT1A receptor agonists
have been tested by our previous studies using fear conditioning. However, little is
known about the brain regions of anxiolytic actions of 5-HT1A receptor agonists in this
paradigm. In the present study, we investigated the effects of bilateral microinjections
of flesinoxan, a selective 5-HT1A receptor agonist, into the hippocampus, amygdala and
medial prefrontal cortex on the expression of contextual conditioned freezing and the
defecation induced by conditioned fear stress in rats. These results reveal that both
intrahippocampal and...
7.
Caveolin-3 gene mutation in Japanese with rippling muscle disease - Yabe, Ichiro; Kawashima, A; Kikuchi, S; Higashi, T; Fukazawa, T; Hamada, T; Sasaki, H; Tashiro, K
Objectives: Rippling muscle disease (RMD) is a rare myopathy characterized by percussion-induced rapid muscle contractions, muscle mounding, and rippling. Recently a caveolin-3 gene (CAV3) mutation was identified in patients with autosomal dominant RMD. The objective of this study was to determine whether a similar mutation was present in two Japanese families with this condition.
Patients and methods: Clinical examination, mutational analysis, and muscle immunohistochemistry were carried out in six patients from two Japanese RMD pedigrees.
Results: Apart from the atrophy of the intrinsic muscles in their hands and a slight muscle weakness in their fingers, the clinical features of our patients were...
8.
Four mutations of the spastin gene in Japanese families with spastic paraplegia - Basri, Rehana; Yabe, Ichiro; Soma, Hiroyuki; Takei, Asako; Nishimura, Hiroyuki; Machino, Yuka; Kokubo, Yasumasa; Kosugi, Masafumi; Okada, Ryuichirou; Yukitake, Motohiro; Tachibana, Hisao; Kuroda, Yasuo; Kuzuhara, Shigeki; Sasaki, Hidenao
Hereditary spastic paraplegia (HSP) is a group of genetically heterogeneous neurodegenerative disorders characterized by slowly progressive spasticity and weakness of the lower limbs. HSP is caused by failure of development or selective degeneration of the corticospinal tracts, which contain the longest axons in humans. The most common form of HSP is caused by mutations of the spastin gene (SPAST), located on chromosome 2p21-p22, which encodes spastin, one of the ATPases associated with diverse cellular activities (AAA). In this study, we detected four causative mutations of SPAST among 14 unrelated patients with spastic paraplegia. Two missense mutations (1447A-->G, 1207C-->G) and two...
9.
MSA-C is the predominant clinical phenotype of MSA in Japan : Analysis of 142 patients with probable MSA - Yabe, Ichiro; Soma, Hiroyuki; Takei, Asako; Fujiki, Naoto; Yanagihara, Tetsuro; Sasaki, Hidenao
We investigated the clinical features and mode of disease progression in 142 patients with probable multiple system atrophy (MSA) according to the Consensus Criteria. The subjects included 84 men and 58 women with a mean age at onset of 58.2 ± 7.1 years (range: 38–79 years). Cerebellar signs were detected in 87.3% of these patients at the time of initial examination, and were found in 95.1% of them at latest follow-up. MSA-C was diagnosed in 83.8% of the patients at their first examination. Parkinsonism was initially detected in 28.9% of the patients, increasing to 51.4% at the latest follow-up. Among...
10.
Focal fractionated radiotherapy for intramedullary spinal arteriovenous malformations: 10-year experience. - Hida, Kazutoshi; Shirato, Hiroki; Isu, Toyohiko; Seki, Toshitaka; Onimaru, Rikiya; Aoyama, Hidefumi; Ushikoshi, Satoshi; Miyasaka, Kazuo; Iwasaki, Yoshinobu
Object. Radiosurgical treatment of spinal arteriovenous malformations (AVMs) is becoming a practical therapeutic
option as methodology improves, but no comparative study has yet been published on focal fractionated radiotherapy. The
authors report their experience with conventional and hypofractionated radiotherapy for spinal AVM.
Methods. Candidates for this study were patients who experienced symptoms due to an intramedullary AVM but were
ineligible for embolization or surgery. Of 21 patients with spinal AVMs, 10 cases in a 10-year period met this criterion.
Angiography and contrast-enhanced computerized tomography scanning were used for treatment planning in all cases.
Fractionated radiotherapy was performed using a linear accelerator, extracranial immobilization system, and frequent
orthogonal...
11.
Effect of carbamazepine on the single oral dose pharmacokinetics of perospirone and its active metabolite - Masui, Takuya; Kusumi, Ichiro; Takahashi, Yoshito; Koyama, Tsukasa
Perospirone is a serotonin 5-HT2A and dopamine D2 receptor antagonist which originated in Japan. It has been shown that perospirone is metabolized to ID-15036 mainly by CYP3A4 based on an in vitro study. To investigate the metabolism of perospirone in humans, the authors measured the concentration of perospirone and ID-15036 after a single oral dose of perospirone (8 mg) in 10 healthy male subjects, before and during coadministration of carbamazepine, known as a potent inducer of CYP3A4. Before carbamazepine coadministration, the peak plasma concentrations ± SD of perospirone and ID-15036 were 4.0 ± 4.3 and 11.7 ± 7.1 ng/ml, respectively....
12.
Heredity in Multiple System Atrophy - Soma, Hiroyuki; Yabe, Ichiro; Takei, Asako; Fujiki, Naoto; Yanagihara, Tetsuro; Sasaki, Hidenao
We investigated the family histories of 157 Japanese patients with probable or
possible multiple system atrophy (MSA). A family history of neurodegenerative
disorders was only detected in three MSA patients (1.9%). We evaluated these patients
by careful neurological examination, neuroimaging studies, and genetic studies to
exclude hereditary spinocerebellar ataxia with a similar clinical phenotype to MSA. The
results indicated that one of them had a family history of MSA. Although the familial
presence of neurodegenerative disorders is rare in MSA patients, the existence of such
cases suggests that MSA may have a genetic background.
13.
Nonsuture dural repair using polyglycolic acid mesh and fibrin glue: clinical application to spinal surgery - Hida, Kazutoshi; Yamaguchi, Satoshi; Seki, Toshitaka; Yano, Shunsuke; Akino, Minoru; Terasaka, Shunsuke; Uchida, Takanori; Iwasaki, Yoshinobu
Background: In spinal surgery, repair of the dura is difficult when it is torn, fragile, or is ossified
as in cases with OPLL. We report our experience with a non-suture dural repair technique in
patients undergoing spinal surgery; it employs a dura substitute composed of polyglycolic acid
(PGA) mesh and fibrin glue. Here we report the efficacy and safety of non-suture duroplasty
using PGA mesh and fibrin glue (PGA-fibrin sheet).
Methods: The artificial dura mater is composed of a PGA-fibrin sheet. The dural defect is
covered with a patch sprayed with fibrin glue without suturing to the dura mater. We first
evaluated this technique in an experimental...
14.
Developmental localization of potassium chloride co-transporter 2 in granule cells of the early postnatal mouse cerebellum with special reference to the synapse formation - Takayama, C.; Inoue, Y.
In the adult CNS, GABA is the predominant inhibitory neurotransmitter, mediating the hyperpolarization of membrane potential and regulating the glutamatergic activity. In the immature CNS, on the other hand, GABA mediates depolarization and is involved in controlling morphogenesis. This developmental shift in GABA actions from depolarization to hyperpolarization occurs as a result of decreasing the intracellular chloride ion (Cl−) concentration ([Cl−]i) which is regulated by the potassium (K+)-Cl− co-transporter 2 (KCC2). To clarify the time-course of changes in the GABA actions during development, we examined the developmental localization of the KCC2 in the granule cells of the postnatal mouse cerebellum...
15.
Formation of GABAergic synapses in the cerebellum - Takayama, Chitoshi
In the adult central nervous system (CNS), γ‐amino butyric acid (GABA) is a predominant inhibitory neurotransmitter, and is involved in the expression of various higher brain functions. In the cerebellum, formation of GABAergic synapses is crucial for cerebellar functions. However, it is not fully understood how GABAergic synapses and networks are formed. We are morphologically investigating the developmental changes in GABAergic signaling and the mechanisms underlying the assembly of GABAergic synapses using the cerebellum, which provides an ideal system for the investigation of brain development. The anatomy and development of GABAergic synapses and networks in the cerebellar cortex are reviewed,...
16.
Developmental expression of GABA transporter-1 and 3 during formation of the GABAergic synapses in the mouse cerebellar cortex. - Takayama, Chitoshi; Inoue, Yoshiro
In the brain, γ-amino butyric acid (GABA), released extrasynaptically and synaptically from GABAergic neurons, plays important roles in morphogenesis, expression of higher functions and so on. In the GABAergic transmission system, plasma membrane GABA transporters (GATs) mediate GABA-uptake from the synaptic cleft in the mature brain and are thought to mediate diacrine of cytosolic GABA in the immature brain. In the present study, we focused on two GATs (GAT-1 and GAT-3) in the mouse cerebellar cortex, which are widely localized in neural and glial cells. Firstly, we examined the localization of GATs in the dendrites and cell bodies of developing...
17.
Extrasynaptic localization of GABA in the developing mouse cerebellum - Takayama, Chitoshi; Inoue, Yoshiro
In the adult brain, γ-amino butyric acid (GABA) is synaptically released and mediates inhibitory transmission. Recent studies have revealed that GABA is a trophic factor for brain development. To reveal the distribution of GABA and its secretion mechanisms during brain development, we investigated the immunohistochemical localization of two molecules, GABA and vesicular GABA transporter (VGAT), which is a GABAergic vesicle protein, in the developing mouse cerebellum by means of newly developed antibodies. Furthermore, we tested the relationship between developmental changes in distribution of above two molecules in the presynapses and ontogeny of GABAergic synapses. GABAergic synapses were detected by immunohistochemistry...
18.
Morphological development and maturation of the GABAergic synapses in the mouse cerebellar granular layer - Takayama, Chitoshi; Inoue, Yoshiro
In the adult central nervous system (CNS), γ-amino butyric acid (GABA) is a predominant inhibitory neurotransmitter, which regulates glutamatergic activity. Recent studies have revealed that GABA serves as an excitatory transmitter in the immature CNS, and is involved in brain morphogenesis. To elucidate how GABA exerts its effect on immature neurons and how GABAergic synapses are formed, we examined both development of pre- and post-synaptic elements of the GABAergic synapses formed between granule and Golgi cells in the mouse cerebellar granular layer. Immunohistochemistry for glutamic acid decarboxylase (GAD) demonstrated that GABA was localized throughout the Golgi cells before postnatal day...
19.
Transient expression of GABAA receptor α2 and α3 subunits in differentiating cerebellar neurons - Takayama, Chitoshi; Inoue, Yoshiro
In the adult mammalian brain, synaptic transmission mediated by γ-amino butyric acid (GABA) plays a role in inhibition of excitatory synaptic transmission. During brain development, GABA is involved in brain morphogenesis. To clarify how GABA exerts its effect on immature neurons, we examined the expression of the GABAA receptor α2 and α3 subunits, which are abundantly expressed before α1 and α6 subunits appear, in the developing mouse cerebellum using in situ hybridization. Proliferating neuronal precursors in the ventricular zone and external granular layer expressed neither α2 nor α3 subunits. Hybridization signals for the α2 and α3 subunit mRNAs first appeared...
20.
Normal formation of the postsynaptic elements of GABAergic synapses in the reeler cerebellum - Takayama, Chitoshi; Inoue, Yoshiro
Synaptic transmission mediated by γ-amino butyric acid (GABA) plays an important role in inhibition of glutamatergic excitatory transmission and expression of higher brain functions, such as memory, learning and anxiety. To elucidate mechanisms underlying formation of the postsynaptic elements for GABAergic transmission, we employed the reeler mutant mice in this study. In the reeler cerebellum, abnormal cytoarchitecture and an aberrant environment affect the formation of neural networks and maturation of neurons. We examined the expression and localization of GABAA receptor α subunits in the reeler cerebellum and determined whether various abnormalities in the reeler mice affected formation of the postsynaptic...
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