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991.
992.
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
993.
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994.
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.995.
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
996.
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.997.
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
998.
Mitsuru Osada Satoshi Takeda Ryuji Ogawa Takashi Iida Ken Umetani Takao Sawanobori Hiroshi Ijiri Sadayoshi Komori Kohji Tamura Kiyotaka Kugiyama 《Experimental & Clinical Cardiology》2001,6(4):211-213
BACKGROUND:
Angiocardiography is an important diagnostic modality for evaluation of heart disease. It is well known that the concentration of plasma atrial natriuretic peptide (ANP) increases after injection of contrast medium. On the other hand, some patients with hypertension, heart failure or cardiac hypertrophy have an increased plasma ANP concentration at baseline; however, whether ANP increases after angiography in these patients is unknown.OBJECTIVES:
To investigate changes in plasma ANP concentrations after angiocardiography in patients with high ANP concentrations at baseline.PATIENTS AND METHODS:
Plasma ANP concentrations of 32 patients with angina pectoris were measured before and after angiocardiography. They were then classified into two groups according to their ANP concentration before examination.RESULTS:
ANP concentration after the injection of contrast medium increased significantly in patients with normal ANP concentrations before angiography but did not change in patients with high ANP concentrations at rest.CONCLUSIONS:
These results suggest that the absence of an increase in ANP after angiography may in part be due to reduced sensitivity to the angiography stimulus or to an already maximal activation of ANP secretion at baseline. 相似文献999.
1000.
Takahiro Tsuchikawa Satoshi Hirano Toru Nakamura Keisuke Okamura Eiji Tamoto Toshiaki Shichinohe 《Postgraduate medicine》2015,127(3):273-276
Increasing evidence has contraindicated extended radical dissection of pancreatic adenocarcinoma (PC). With the recent improvement of perioperative management techniques and multimodal treatment strategy for PC, concomitant major vessel resection and reconstruction has thus been aggressively attempted in association with comparatively better pathologically negative surgical margins and postoperative survival. We have discussed the clinical relevance of concomitant major vessel resection mainly focusing on indications for such resection with borderline resectable tumor associated with chemoradiotherapy, distal pancreatectomy with en bloc celiac axis resection for pancreatic body and tail cancer, and adjuvant surgery for initially unresectable pancreatic cancer. 相似文献