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101.
Funato Kouichi Yamashita Chikamasa Kamada Junko Tominaga Sachiko Kiwada Hiroshi 《Pharmaceutical research》1994,11(3):372-376
Several plasma components, such as complement (C) components, play a role in the clearance of liposomes from the circulation. The interactions between liposomes and the C system were investigated in this study. Multilamellar vesicle (MLV) liposomes, which were damaged by activation of the complement, became susceptible depending on the density of cetylmannoside (Man) on the liposome membrane, and activation proceeded through the alternative C pathway as observed for liposomes without Man (PC-MLV) (K. Funato et al, Biochim. Biophys. Acta 1103:198–204, 1992). In addition, the capacity of Man-modified liposomes (Man-MLV) to activate the alternative C pathway was abolished by preadsorption of plasma with Man-MLV but not with PC-MLV. The results suggest that a specific plasma factor adsorbed with Man-MLV was responsible for the augmentation of the C activation and, further, that the rapid clearance of Man-MLV from the circulation is caused by both enhanced C-mediated liposome permeability and enhanced C-mediated phagocytosis of liposomes. 相似文献
102.
A case of a melanotic schwannoma presenting as a soft tissue mass of the abductors of the hip is reported. The radiographic findings suggested myositis ossificans, but several subtle findings raised the concern for something else. A bilobed appearance, lack of classic zoning pattern of the ossification, and atypical pain pattern should alert the physician. Biopsy should be considered if the radiographic and clinical presentations are not classic for myositis ossificans. 相似文献
103.
Nishizaki T Matsuoka T Nomura T Matsuyama S Watabe S Shiotani T Yoshii M 《Brain research》1999,826(2):443-288
Nefiracetam, a nootropic agent, enhanced the slope of field excitatory postsynaptic potentials in the CA1 region of rat hippocampal slices to about 170% of basal levels, being evident still at 4-h washing-out of the drug. A similar sustained enhancement (>/=16 h after i.m. injection with nefiracetam) was observed in the population spikes recorded from the granular cell layer of the intact mouse hippocampus. Saturation of the enhancement in the synaptic strength occluded potentiation obtained with long-term potentiation (LTP) induced by high-frequency (tetanic) stimulation, and vice versa. Interestingly, the facilitatory action of nefiracetam was blocked by either the nicotinic acetylcholine (ACh) receptor antagonists, alpha-bungarotoxin and mecamylamine, or the selective protein kinase C (PKC) inhibitor, GF109203X, but in contrast, it was not affected by D-2-amino-5-phosphonovaleric acid (APV), a selective N-methyl-D-aspartate (NMDA) receptor antagonist. The results of the present study suggest that nefiracetam, whereas the action is independent of NMDA receptors, induces an 'LTP-like' facilitation of hippocampal synaptic transmission as a consequence of modulation of nicotinic ACh receptors and PKC. This may represent a likely mechanism underlying the cognition-enhancing actions of nefiracetam. 相似文献
104.
H. Ozaki MD H. Sato M. Hori T. Matsuyama K. Imai H. Yokoyama A. Kitabatake M. Inoue T. Kamadal 《European journal of clinical pharmacology》1992,43(5):455-461
Summary Xamoterol acts as a
1-adrenoceptor agonist at low sympathetic activity and as an antagonist at high activity. Although its long-term efficacy has been proven in patients with mild to moderate heart failure, it remains unclear which effect, agonism or antagonism, accounts for its long-term activity.To clarify the effect of xamoterol on cardiac sympathetic activity in daily life, 24-h R-R interval histograms were obtained during administration of xamoterol 100 mg b. d. for 1 week to 10 patients with mild to moderate heart failure. Eight normal subjects were also studied as controls. To examine the relation between the effect of xamoterol and sympathetic activity, plasma noradrenaline (NA) levels were measured under 5 graded conditions simulating daily living.Xamoterol administration significantly decreased the standard deviation of the R-R interval, both in patients with heart failure and in normal subjects. The mean R-R interval, however, was increased in patients with heart failure, relative to normal subjects.In both groups, the R-R interval histograms had two peaks, i. e. a short daytime peak and a long night-time peak. Xamoterol decreased the median of the night-time peak without changing the daytime peak in normal subjects. In contrast, it increased the median of the daytime peak without producing a significant change in the nighttime peak in patients with heart failure. Levels of plasma NA were significantly higher in patients than in normal subjects under all conditions.Thus, in normal subjects xamoterol predominantly increased the slower heart rate at night with only a minor effect on the higher heart rate in the daytime, whereas it predominantly attenuated the daytime tachycardia induced by sympathetic stimulation in patients with heart failure.It is concluded that xamoterol tends overall to act as a-adrenoceptor antagonist during the day, especially in the daytime in patients with mild to moderate heart failure. Its antagonist rather than its agonist effect may account for the long-term efficacy of xamoterol in patients with mild to moderate heart failure. 相似文献
105.
Komai S Matsuyama T Matsumoto K Kato K Kobayashi M Imamura K Yoshida S Ugawa S Shiosaka S 《The European journal of neuroscience》2000,12(4):1479-1486
We found that neuropsin, an extracellular matrix serine protease, has a regulatory effect on Schaffer-collateral long-term potentiation (LTP) in the mouse hippocampus. Bath application of 1-170 nM recombinant neuropsin modulated early phase LTP in the Schaffer-collateral pathway with a 'bell-shape' dose-response curve. The maximum enhancing activity (134% of control LTP) was found at approximately 2.5 nM. Bath application of a neutralizing antibody against neuropsin in the hippocampal slice resulted in a marked inhibition of the tetanus-induced early phase of LTP. The in vivo continuous intraventricular infusion of an antisense oligonucleotide against neuropsin significantly reduced the amplitude of the tetanus-induced early phase of LTP in vitro. Neuropsin did not directly change the N-methyl D-aspartate (NMDA) current. Thus, neuropsin appears to act as a regulatory molecule in the early phase of LTP via its proteolytic function on extracellular matrix rather than affecting NMDA receptor-mediated calcium increase. 相似文献
106.
Peripheral nerve repair and grafting techniques: a review 总被引:3,自引:0,他引:3
In this review, various conventional nerve repair techniques including direct epineurial repair, grouped fascicular repair, fascicular repair, and nerve grafting are described. The indications for use, as well as the relative advantage and disadvantage, of each technique are discussed. The experimental and clinical evidence from a review of the pertinent literature does not demonstrate a significant difference in outcome of one method over the others. Surgical decisions should be made by a thorough evaluation of all aspects of the nerve injury and surgical methods. All nerve injuries cannot be repaired using only one type of nerve repair method. The surgeon should be familiar with all the techniques described and be prepared to use them under appropriate circumstances. 相似文献
107.
Haemodynamic effects of the crude venom from nematocysts of the box-jellyfish Chiropsalmus quadrigatus (Habu-kurage) in anaesthetized rabbits. 总被引:1,自引:0,他引:1
Tomoyuki Koyama Katsuhiko Noguchi Toshihiro Matsuzaki Mayuko Sakanashi Junko Nakasone Kanako Miyagi Makiko Sakanashi Matao Sakanashi 《Toxicon》2003,41(5):621-631
Haemodynamic effects of saline-extracted venom from nematocysts isolated from tentacles of the box-jellyfish Chiropsalmus quadrigatus (Habu-kurage) were investigated. In anaesthetized rabbits, i.v. injections of the venom produced hypotension following a transient hypertension. Mean femoral arterial blood flow markedly decreased immediately after the injection and femoral vascular resistance increased. Left ventricular dP/dt remarkably decreased after a transient and small increase, and heart rate decreased. Left ventricular end-diastolic pressure markedly elevated. All of the above changes by 0.2-5 microg/kg of the venom expressed as the amount of protein were seen dose-dependently and occurred without tachyphylaxis. In five of seven animals received an injection of the venom at 10 microg/kg, irreversible cardiac arrest occurred. Changes produced by 1 or 2 microg/kg of the venom were significantly attenuated either by heating the venom at 40 degrees C for 10min or by pretreatment with diltiazem. These results indicate that the venom from Habu-kurage has both vasoconstrictor and cardiodepressive effects, and suggest that these thermolabile actions may be due partly to activation of voltage-dependent calcium channels and probably subsequent calcium-overload. 相似文献
108.
Nagata T Matsuyama M Kiriike N Iketani T Oshima J 《The Journal of nervous and mental disease》2000,188(5):280-286
Although maladaptive coping strategies in eating disorder patients have been reported, the relationship between impulsivity and coping strategy has not previously been studied. Subjects consisted of 43 patients with anorexia nervosa restricting type (AN-R), 42 patients with anorexia nervosa binge eating/purging type (AN-BP), 71 patients with bulimia nervosa purging type (BN), and 97 controls. The Coping Inventory for Stressful Situations was used to evaluate coping strategies. Only AN-BP patients had a significantly lower task oriented-coping score than controls, and AN-R and BN patient groups used significantly less social diversion-avoidance coping strategies than controls. Emotion-oriented coping scores of AN-BP and BN patients were significantly higher than those of controls. In addition, impulsive BN patients had significantly higher emotional coping scores than less impulsive BN patients. These results suggest that maladaptive coping strategies may be a perpetuating factor even for impulsive patients and emphasizing a change in maladaptive coping strategies may be a useful treatment strategy even for highly impulsive patients. 相似文献
109.
Junko Miyamoto Hiroshi Asanuma Hideo Nakai Tomonobu Hasegawa Hajime Nawata Yukihiro Hasegawa 《Clinical Pediatric Endocrinology》2006,15(4):151-162
The prevalence of abnormalities in androgen receptor gene (AR) among patients with
ambiguous genitalia is unknown. Moreover, endocrinological data from prepubertal patients
with AR mutation are very limited. Thus, the aim of this study was to examine the
prevalence of abnormalities in AR among patients with both ambiguous genitalia, which was
defined as a combination of two or more genital abnormalities (i.e. hypospadias,
microphallus (penile length < 25 mm), hypoplastic scrotum, bifid scrotum, undescended
testis) in this study, and normal to elevated T levels. We also compared the
endocrinological data of prepubertal patients with AR mutation and ambiguous genitalia
with that of those without the AR mutation. We screened 26 Japanese prepubertal 46,XY
patients (five from three families were included) with both ambiguous genitalia and normal
to elevated T levels. Mutations in AR were found in three (two of the three were related).
Among the 23 patients without mutation in AR, the steroid 5-alpha-reductase 2 gene
(SRD5A2) was also examined in eight patients with elevated T/dehydrotestosterone ratio
after the hCG (>10) or with undervirilized family members. No mutation in SRD5A2 was
found. Characteristics of the three patients with mutation in AR were compared with the 23
patients without mutation. In two patients, basal T levels (0.3, 0.2 ng/ml) and peak T
levels after the hCG tests (8.3, 8.5 ng/ml) tended to be higher, and the peak LH/ peak FSH
ratios after the GnRH tests (4.6, 4.0) were higher than in patients without mutation, at
the ages of 1 yr and 9 mo and 3 yr and 8 mo, respectively. In conclusion, an abnormality
in either AR or SRD5A2 was not common among patients with ambiguous genitalia and normal
testosterone secretion. Elevated peak LH/peak FSH ratio (≥4) after the GnRH test in
addition to detectable basal T levels and elevated peak T levels after the hCG test may
infer AR abnormality in prepubertal patients with ambiguous genitalia at the age of one
and over, although further study is needed, because our data were limited. 相似文献
110.
Up-regulation of glial cell line-derived neurotrophic factor (GDNF) following traumatic spinal cord injury 总被引:10,自引:0,他引:10
Satake K Matsuyama Y Kamiya M Kawakami H Iwata H Adachi K Kiuchi K 《Neuroreport》2000,11(17):3877-3881