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991.
Keishi Maruo Tetsu Nagata Satoshi Yamamoto Kaoru Nagai Yukio Yajima Soji Maruo Tomoyuki Nishizaki 《Brain research》2003,977(2):294
In a whole-cell patch-clamp configuration, currents through N-methyl-
-aspartate (NMDA) and α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) receptor channels were monitored in cultured rat hippocampal neurons, and those currents were depressed to 25 and 28% of basal levels, respectively, by 3-min treatment with tunicamycin (10 μM), an inhibitor of protein N-glycosylation. Tunicamycin (10 μM) reduced amplitude of population spikes elicited in the dentate gyrus of rat hippocampal slices, reaching 78% of basal levels 60 min after the beginning of treatment, and long-term potentiation (LTP) of the perforant path was never induced in the presence of tunicamycin. Tunicamycin, thus, appears to serve as a modulator for NMDA and AMPA receptors, regardless of N-glycosylation, thereby inhibiting neurotransmission and LTP in the dentate gyrus. 相似文献
992.
993.
A comprehensive analysis identifies BRAF hotspot mutations associated with gliomas with peculiar epithelial morphology 下载免费PDF全文
Ryusuke Hatae Nobuhiro Hata Satoshi O. Suzuki Koji Yoshimoto Daisuke Kuga Hideki Murata Yojiro Akagi Yuhei Sangatsuda Toru Iwaki Masahiro Mizoguchi Koji Iihara 《Neuropathology》2017,37(3):191-199
Brain tumors harbor various BRAF alterations, the vast majority of which are the BRAF kinase‐activating V600E mutation. BRAF mutations are most frequently detected in certain subtypes of low‐grade glioma, such as pilocytic astrocytoma (PA), pleomorphic xanthoastrocytoma (PXA), ganglioglioma (GG) and dysembryoplastic neuroepithelial tumor (DNT). However, it is unclear whether gliomas harboring BRAF mutations can be invariably regarded as these glioma subtypes or their derivatives. To address this question, we analyzed 274 gliomas in our institutional case series. We performed high‐resolution melting analyses and subsequent direct Sanger sequencing on DNA isolated from snap‐frozen tumor tissues. As expected, BRAF mutations were detected in the aforementioned low‐grade gliomas: in 4/27 PAs, 2/3 PXAs, 4/8 GGs, and 1/6 DNTs. In addition to these gliomas, 1/2 astroblastomas (ABs) and 2/122 glioblastomas (GBs) harbored BRAF mutations. Pathological investigation of the two GBs revealed that one was a GB displaying epithelial features that presumably arose from a precedent GG, whereas the other GB, which harbored a rare G596 A mutation, showed marked epithelial features, including astroblastic rosettes. Our results indicate that in addition to being present in established BRAF‐associated gliomas, BRAF mutations might be associated with epithelial features in high‐grade gliomas, including sheet‐like arrangement of polygonal tumor cells with a plump cytoplasm and astroblastic rosettes, and thus could potentially serve as a genetic marker for these features. 相似文献
994.
Takuya Sasaki Satoshi Kodama Naohiko Togashi Yuichiro Shirota Yusuke Sugiyama Shin-ichi Tokushige Satomi Inomata-Terada Yasuo Terao Yoshikazu Ugawa Masashi Hamada 《Brain stimulation》2018,11(2):400-410
Background
Responses to continuous theta burst stimulation (cTBS) applied to the human primary motor cortex are highly variable between individuals. However, little is known about how to improve the after-effects of cTBS by adjusting the protocol characteristics.Objective
We examined whether current directions adopted in the measurement of cortical motor excitability indexed as motor evoked potentials (MEPs) affect the responses to cTBS. We also tested whether the stimulus intensity of cTBS influences the after-effects.Methods
Thirty-one healthy volunteers participated. The after-effects of cTBS with the conventional intensity of 80% of individual active motor threshold (AMT) (cTBS80%) were tested by measuring MEP amplitudes induced by not only posterior-anterior (PA) but also anterior-posterior (AP) and biphasic (PA-AP) currents. We also investigated cTBS with 65% AMT (cTBS65%) and 100% AMT (cTBS100%) in subjects who showed depression of MEP amplitudes after cTBS80%, as well as cTBS65% in subjects in whom facilitation of MEPs was induced by cTBS80%.Results
Current directions in MEP measurement had no influence on the cTBS responses. In subjects whose MEPs were depressed by cTBS80%, cTBS100% partly induced MEP facilitation, while cTBS65% abolished the after-effects. In subjects who showed MEP facilitation by cTBS80%, cTBS65% partly induced MEP depression.Conclusions
Stimulus intensity of cTBS influenced the responses to cTBS, and lowering stimulus intensity induced the expected after-effects of cTBS in some subjects. 相似文献995.
Efficacy and safety of switching from basal insulin to once‐daily insulin degludec/insulin aspart in Japanese patients with inadequately controlled type 2 diabetes: A 4‐week,randomized, open‐label,treat‐to‐target study 下载免费PDF全文
Yoshio Nagai Ami Nishine Eriko Hashimoto Taiga Nakayama Yosuke Sasaki Mariko Murakami Satoshi Ishii Hiroyuki Kato Yasushi Tanaka 《Journal of diabetes investigation.》2018,9(3):567-572
Aims/Introduction
A prospective, 4‐week, single‐center, randomized, open‐label, parallel‐group, treat‐to‐target study was carried out to develop an algorithm for safe and effective switching from basal insulin to once‐daily insulin degludec/insulin aspart (IDegAsp) in patients with inadequately controlled type 2 diabetes.Materials and Methods
Patients were randomly assigned to continue their current basal insulin therapy (n = 10) or to switch to IDegAsp on a 1:1 unit basis (n = 10). The insulin dose could be titrated once weekly, targeting a self‐measured blood glucose of 80–100 mg/dL before breakfast. A mixed meal test was carried out at baseline and after 4 weeks.Results
After 4 weeks, the mean daily dose of insulin was similarly increased by 60% in both groups, and there was a significant decrease of mean plasma glucose and glucose area under the glucose concentration vs time curve for 2 h in the meal test. The mean estimated treatment difference (IDegAsp group ? basal insulin group) of the mean plasma glucose level was ?28 mg/dL (95% confidence interval ?47 to ?8, P = 0.008) after 4 weeks and that of the area under the glucose concentration vs time curve for 2 h was ?2,800 mg/min/dL (95% confidence interval ?5,300 to ?350, P = 0.028), confirming the superiority of IDegAsp to basal insulin. In the IDegAsp group, the 2‐h postprandial plasma glucose level was significantly decreased to the fasting plasma glucose range. There were no confirmed hypoglycemic episodes in either group during the 4‐week study period.Conclusions
After switching from basal insulin, the IDegAsp dose can be uptitrated by 60% based on fasting plasma glucose data. However, monitoring of postprandial glucose should be considered before further uptitration of IDegAsp.996.
Older Korean adults have lower physical function despite longer exercise times compared to their Japanese counterparts: A Japan‐Korea comparative study 下载免费PDF全文
997.
Analysis of antigen‐antibody cross‐reactivity among lineages and sublineages of Babesia microti parasites using human babesiosis specimens 下载免费PDF全文
998.
Satoshi Nozaki Aya Mawatari Yuka Nakatani Emi Hayashinaka Yasuhiro Wada Yukihiro Nomura Takahito Kitayoshi Kouji Akimoto Shinji Ninomiya Hisashi Doi Yasuyoshi Watanabe 《Molecular imaging and biology》2018,20(6):1001-1007
Purpose
Thiamine is an essential component of glucose metabolism and energy production. The disulfide derivative, thiamine tetrahydrofurfuryl disulfide (TTFD), is better absorbed than readily-available water-soluble thiamine salts because it does not require the rate-limiting transport system required for thiamine absorption. However, the detailed pharmacokinetics of thiamine and TTFD under normal and pathological conditions have not yet been clarified. C-11-labeled thiamine and TTFD were recently synthesized by our group. In this study, to clarify the differences in pharmacokinetics and metabolism of these probes, a quantitative PET imaging study and radiometabolite analysis of C-11-labeled thiamine and TTFD were performed in the rat heart.Procedures
Positron emission tomography (PET) imaging with [11C]thiamine and [11C]TTFD was performed in normal rats to determine the pharmacokinetics of these probes, and the radiometabolites of both probes from the blood and heart tissue were analyzed by thin-layer chromatography.Results
Accumulation of [11C]TTFD was significantly higher than that of [11C]thiamine in the rat heart. Moreover, as a result of the radiometabolite analysis of heart tissue at 15 min after the injection of [11C]TTFD, thiamine pyrophosphate, which serves as a cofactor for the enzymes involved in glucose metabolism, was found as the major radiometabolite and at a significantly higher level than in the [11C]thiamine-injected group.Conclusions
PET imaging techniques for visualizing the kinetics and metabolism of thiamine using [11C]thiamine and [11C]TTFD were developed in this study. Consequently, noninvasive PET imaging for the pathophysiology of thiamine-related cardiac function may provide novel information about heart failure and related disorders.999.
Anzai H Saijo T Nakajima R Tezuka N Takagi T Tsunoda T Kobayashi N Nakamura S Yamaguchi T 《Journal of cardiology》2000,36(1):17-27
OBJECTIVES: The presence of microvascluar impairment was evaluated in 154 patients with vasospastic angina identified by the acetylcholine provocation test. METHODS: Coronary flow reserve was evaluated with a Doppler flow guidewire in 128 vessels of 72 patients with chest pain, but no significant coronary stenosis(less than 50% stenosis) and no clinical factors that affect coronary flow reserve. Coronary flow reserve was obtained from the ratio of adenosine triphosphate-induced maximum/baseline averaged peak velocity. These vessels were classified into 2 categories according to whether acetylcholine-induced vasospasm was positive or negative. Vasospasm positive was defined as more than 90% stenosis provoked with chest pain and/or ischemic ST change. Positive vessels were subdivided according to focal or diffuse vasospasm. These vessels were also classified into 2 other categories according to whether vasospasm in the distal artery was positive or negative. RESULTS: Coronary flow reserve was significantly lower in vessels with vasospasm than in vessels without vasospasm in patients without vasospasm(2.9 +/- 0.8 vs 3.6 +/- 1.0, p = 0.0005). Coronary flow reserve was significantly lower in vessels without vasospasm in patients with vasospasm than in vessels without vasospasm in patients without vasospasm(3.0 +/- 0.8 vs 3.6 +/- 1.0, p = 0.03). There was no significant difference in coronary flow reserve between vessels with vasospasm and vessels without vasospasm in patients with vasospasm(2.9 +/- 0.8 vs 3.0 +/- 0.8, p = 0.8). There was no significant difference in coronary flow reserve between focal and diffuse vasospasm(3.2 +/- 0.8 vs 2.9 +/- 0.8, p = 0.3). Coronary flow reserve was significantly lower in vessels with vasospasm in the distal artery than in vessels without vasospasm in the distal artery (2.8 +/- 0.8 vs 3.4 +/- 1.0, p = 0.004). CONCLUSIONS: Patients with vasospastic angina have microvascular impairment in both vessels with vasospasm, and vessels without vasospasm. Microvascular impairment is prominent in vessels with vasospasm in the distal artery. 相似文献
1000.
Electroretinogram analysis of relative spectral sensitivity in genetically identified dichromatic macaques 下载免费PDF全文
Akitoshi Hanazawa Akichika Mikami Puti Sulistyo Angelika Osamu Takenaka Shunji Goto Akishi Onishi Satoshi Koike Tetsuo Yamamori Keichiro Kato Aya Kondo Bambang Suryobroto Achmad Farajallah Hidehiko Komatsu 《Proceedings of the National Academy of Sciences of the United States of America》2001,98(14):8124-8127
The retinas of macaque monkeys usually contain three types of photopigment, providing them with trichromatic color vision homologous to that of humans. However, we recently used molecular genetic analysis to identify several macaques with a dichromatic genotype. The affected X chromosome of these animals contains a hybrid gene of long-wavelength-sensitive (L) and middle-wavelength-sensitive (M) photopigments instead of separate genes encoding L and M photopigments. The product of the hybrid gene exhibits a spectral sensitivity close to that of M photopigment; consequently, male monkeys carrying the hybrid gene are genetic protanopes, effectively lacking L photopigment. In the present study, we assessed retinal expression of L photopigment in monkeys carrying the hybrid gene. The relative sensitivities to middle-wavelength (green) and long-wavelength (red) light were measured by electroretinogram flicker photometry. We found the sensitivity to red light to be extremely low in protanopic male monkeys compared with monkeys with the normal genotype. In female heterozygotes, sensitivity to red light was intermediate between the genetic protanopes and normal monkeys. Decreased sensitivity to long wavelengths was thus consistent with genetic loss of L photopigment. 相似文献