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81.
Akagawa H Takano Y Ishii A Mizuno S Izui R Sameshima T Kawamura N Dobashi K Yoshioka T 《The Journal of antibiotics》1999,52(11):960-970
Stresgenin B was isolated as an inhibitor of heat-induced heat shock protein (HSP) gene expression from a culture broth of Streptomyces sp. AS-9 by silica gel chromatography and HPLC. The molecular formula of the novel compound was determined as C11H13NO5 by high resolution FAB-MS analysis, and the structure was determined by UV, 1H NMR, 13C NMR, HMQC, HMBC, and NOESY spectra. Stresgenin B inhibited heat-induced luciferase reporter-gene expression directed by the human hsp70B promoter in Chinese hamster ovary (CHO) cells at concentrations lower than the concentrations for inhibition of dexamethasone-induced luciferase reporter-gene expression directed by the mouse mammary tumor virus (MMTV)-LTR promoter. The inhibition of heat-induced reporter gene expression was evident even when cells were exposed to stresgenin B only during heat stress treatment. Moreover, the compound inhibited heat-induced syntheses of hsp72/73, hsp90, and hsp110 and thereby suppressed the induction of thermotolerance. Stresgenin B showed moderate cytotoxic activities against several neoplastic cell lines and also showed antibacterial activities against Micrococcus luteus, Bacillus subtilis and Staphylococcus aureus strains. 相似文献
82.
Matsumoto H Ikeda K Nagata N Takayanagi H Mizuno Y Tanaka M Sasaki T 《Journal of medicinal chemistry》1999,42(9):1661-1666
Seventeen 1,2,3,4-tetrahydroimidazo[1,5-a]pyrimidine derivatives bearing electron-withdrawing substituents were designed and synthesized by novel ring closure as potential antitumor agents. They were screened for their activities against mouse leukemia L1210 and human oral epidermoid carcinoma KB cell lines, and relationships of structure and antitumor activity in vitro are discussed. It was found that 8-thiocarbamoyl-1,2,3,4-tetrahydroimidazo[1, 5-a]pyrimidin-2(1H)-thione (8c) exhibited activity comparable to that of 5-fluorouracil against both L1210 and KB cells. The existence of both 2-thioxo and 8-substituent with a thioxo group in the molecule is crucial for the cytotoxicity against L1210 and KB cells. A novel procedure for introduction of a double bond between C-3 and C-4 in 8c was developed. Introduction of the 3,4-double bond increased the activity against L1210, but against KB cells the activity decreased by 4-fold. Cytotoxicity of compounds 8c and 8-thiocarbamoyl-1,2-dihydroimidazo[1,5-a]pyrimidin-2(1H)-thione (11c) against human solid tumor and leukemia cell lines was further evaluated. The saturation of the 3,4-double bond led to a significant increase in cytotoxicity against tumor cell lines tested. 相似文献
83.
Horiguchi J Yamashita H Mizuno S Kuramoto Y Kagaya A Yamawaki S Inami Y 《International clinical psychopharmacology》1999,14(1):33-36
Nocturnal eating/drinking syndrome secondary to neuroleptic-induced restless legs syndrome (RLS) occurred under treatment with low-dose haloperidol in a 51-year-old female schizophrenic patient. Polysomnographic investigation showed a low level of sleep efficacy, periodic leg movements, and a strict relationship between nocturnal eating episodes and non-rapid eye movement sleep. Her nocturnal eating and RLS were completely inhibited by clonazepam treatment. To our knowledge, this is the first published case of nocturnal eating/drinking syndrome secondary to neuroleptic-induced RLS. 相似文献
84.
We report five patients with atypical parkinsonism characterized by freezing phenomenon, akinesia and axial rigidity without limb rigidity or tremor. These patients were selected from 252 patients with parkinsonism who were referred to our clinic from 1986 to 1993. They have common clinical features consisting of freezing phenomena involving all four extremities, especially in the initiation of walking, and marked axial rigidity; otherwise, neither supranuclear ophthalmoparesis nor nuchal dystonia was noted. Their clinical features did not change over several years except in one patient who later developed typical manifestations of progressive supranuclear palsy (PSP). Levodopa was of no effect on their symptoms. After excluding other possibilities, it is our conclusion that they represent an atypical form of PSP lying between the pure akinesia of Imai and Narabayashi and the typical form of PSP. 相似文献
85.
Clinical study of growing up aneurysms: report of 25 cases 总被引:1,自引:0,他引:1
T Sampei M Mizuno S Nakajima A Suzuki H Hadeishi T Ishikawa N Yasui 《No shinkei geka. Neurological surgery》1991,19(9):825-830
Twenty-five cases of patients with growing up aneurysms are reported. Growth of the aneurysm was confirmed by repeated angiography within 1 month in 11 cases (short-term group), and for over 1 month in the other 14 cases (long-term group) following the initial angiography. Clinical history, shape and growth pattern of aneurysms, as well as hemodynamic factors that effect the growth were investigated in each group. The aneurysms were classified according to the shape into dome-type (smooth contour) and bleb-type (irregular contour). In all cases of the short-term group, the first angiography was performed because of rupture of the aneurysm. In this group, 4 cases bled again because of enlargement or the development of an aneurysmal bleb. Growth rate and the initial size of the aneurysm did not effect the potential of re-rupture. In the long-term group, 9 cases out of 14 (64.3%) had "non-ruptured aneurysm" at the time of first angiography. In the follow up, 5 cases were ruptured (two because of re-bleeding and three for the first time). In 3 out of these 5 cases, a bleb was demonstrated on initial angiography, and in another case, a bleb was demonstrated in follow-up angiography. Only one case ruptured because of the growth of the aneurysmal dome. Most of the aneurysms that rupture, in the follow-up survey, showed a larger growth rate in comparison with aneurysms that did not rupture. Many cases of this long-term group were associated with hypertension or vascular abnormalities which would effect the aneurysmal growth.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
86.
The maturation of cortical circuitry critically depends on experience. Recently, a model of silent synapse has been proposed as a mechanism of activity-mediated transition of immature synapse to mature synapse. It is not clear, however, how activity could regulate this transition. Here, we show the evidence that endogenous brain-derived neurotrophic factor (BDNF) is required for the maturation of glutamatergic synapse in developing mouse somatosensory cortex. Field potential recordings of thalamocortical glutamatergic synaptic activity with brain slices from the BDNF mutant mice showed that AMPA receptor responses are low, but NMDA receptor responses remain high in layer 4, thus, the relative contribution of AMPA receptor response is significantly lower compared to the age-matched wild-type mouse. Furthermore, optical images of development of thalamocortical connectivity with a voltage-sensitive dye showed that NMDA receptor-dominant synapse is established first in layer 4 and layer 5/6 then AMPA receptor response appears later in concomitant with reduction of NMDA receptor response in layer 4 and that the maturation of the silent synapse is impaired in the BDNF mutant mice. In layer 5/6, NMDA receptor response was suppressed without upregulation of AMPA receptor response. This process also required BDNF function. Interestingly, whisker-trimming of the wild-type mouse from just after birth showed quite similar results with the homozygous mutant of their whiskers left intact. Therefore, we would propose that BDNF is a critical mediator for the maturation of glutamatergic synapse in developing mouse somatosensory cortex. 相似文献
87.
Hatori K Miwa H Sugano K Komine M Tanaka S Mizuno Y 《Parkinsonism & related disorders》2000,6(4):201-203
We report a patient with hemiparkinsonism associated with unilateral striatal necrosis of the contralateral side. The patient was an 18-year-old woman who had a two-month-history of difficulty in executing skilled movements with her right upper extremity. Neurological examination revealed that she had cogwheel rigidity and bradykinesia in her right upper and lower extremities. MRI revealed a well-delineated low signal intensity in T1-weighted and high signal intensity in T2-weighted images in the region of the putamen on the left side. Her laboratory data were unremarkable and mitochondrial gene mutation studies revealed no abnormality. It is extremely rare to encounter a case of parkinsonism associated with unilateral striatal necrosis. 相似文献
88.
A new fibular osteotomy in association with high tibial osteotomy (a comparative study with conventional mid-third fibular osteotomy) 总被引:2,自引:1,他引:1
A new technique for dividing the fibula when performing a high tibial osteotomy is described. The head of the fibula is enucleated
and morselized. The technique is simple and safe with a low complication rate.
Accepted: 17 March 2000 相似文献
Résumé En cas d’ostéotomie supérieure du tibia, nous décrivons une nouvelle technique d’ostéotomie péronière avec énucléation et morcellement de la tête du péroné. On peut employer pour ce faire la même incision cutanée que pour l’ostéotomie du tibia. L’incidence de complications est faible.
Accepted: 17 March 2000 相似文献
89.
A patient presented 4 months after sustaining a fracture of the hook of hamate. X-rays and computed tomography scanning of the carpal tunnel confirmed the presence of an ununited fracture. Low-intensity ultrasound was applied to the fracture site. After 4.5 months of exposure to ultrasound, union was confirmed by both x-rays and computed tomography scanning of the carpal tunnel. (J Hand Surg 2000; 25A:77-79. 相似文献
90.
A 71-year-old man was transferred to our institution with suspected of impending rupture of the abdominal aorta. The clinical manifestations included abdominal pain, pulsatile mass, and abdominal bruit. We made on early diagnosis of aortocaval fistula based on enhanced computed tomography and color Doppler flow imaging. Surgical repair was performed 24 hours after the onset of symptoms. At the introduction of anesthesia, cardiac arrest with high central venous pressure occurred. After resuscitation and rapid clamping of the proximal aorta, surgical closure of the fistula with graft replacement was performed successfully. 相似文献