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991.
Keita Kamata Hiroyuki Hao Toshiyuki Ishige Sayaka Shimodai-Yamada Akira Sezai Makoto Taoka Shunji Osaka Keito Suzuki Masashi Tanaka 《Pathology international》2021,71(4):267-271
Cardiac hemangioma is relatively rare, accounting for approximately 1–3% of all primary heart tumors. This benign tumor may be an incidental lesion, but can also cause arrhythmias, pericardial effusion, congestive heart failure or outflow obstruction. We report a rare case with exophytic cardiac hemangioma arising from the right ventricle. Echocardiography showed an approximately 40 mm round protruding mass on the anterior wall of the right ventricle. Cardiovascular magnetic resonance demonstrated isointense and hyperintense signals on T1- and T2-weighted images, respectively. These imaging studies suggested a pericardial cyst. Perioperative findings indicated a globular, exophytic mass, vascular in nature, arising from the right ventricle. The lesion was resected directly, and the space left by defect in the right ventricular wall was covered with a bovine pericardial patch. Cardiac hemangiomas are generally endoluminal tumors, but we must keep in mind that the differential diagnoses include various pericardial lesions by medical images. 相似文献
992.
Mitsuyoshi Hirokawa Ayana Suzuki Miyoko Higuchi Toshitetsu Hayashi Seiji Kuma Akihiro Miya Akira Miyauchi 《Pathology international》2021,71(6):400-405
This study aimed to clarify the histological alterations following fine-needle aspiration for parathyroid adenoma and discuss the occurrence of diagnostic problems. Among the 392 patients with parathyroid adenoma who underwent resection, fine-needle aspiration was performed for 21 (5.1%) parathyroid adenoma nodules. Histological findings that were significantly more frequent in cases that underwent fine-needle aspiration were considered histological alterations following fine-needle aspiration for parathyroid adenoma, including the following six findings: thick fibrous capsule (71.4%), multilayered fibrous capsules (14.3%), capsular pseudo-invasion (42.9%), fibrous bands (57.1%), hemosiderin deposition (14.3%), and tumor implantation (14.3%). Eighteen parathyroid adenoma nodules (85.7%) exhibited one or more of the six findings. Tumor cells and adipocytes entrapped within the thick fibrous capsule were occasionally observed. The fibrous bands were frequently connected to the thick fibrous capsule. The number of passes, duration between fine-needle aspiration and resection, tumor size, and purpose of fine-needle aspiration were not related to the incidence of histological findings. Because of the histological alterations following fine-needle aspiration for parathyroid adenoma that can be easily mistaken for signs of atypical adenoma or parathyroid carcinoma, we recommend that the six findings be excluded from pathological findings indicating atypical adenoma or parathyroid carcinoma in patients with preoperative fine-needle aspiration. 相似文献
993.
Takashi Ishizone Hiroshi Kato Daisuke Yamazaki Akira Hirao Seiichi Nakahama 《Macromolecular chemistry and physics.》2000,201(11):1077-1087
Anionic polymerizations of phenyl ( 2a ), 4‐methoxyphenyl ( 2b ), 2‐methylphenyl ( 2c ), 2‐tert‐butylphenyl ( 2d ), 3,5‐di‐tert‐butylphenyl ( 2e ), 2,6‐dimethylphenyl ( 1f ), 2,6‐diisopropylphenyl ( 2g ), 2,6‐di‐tert‐butyl‐4‐methylphenyl ( 2h ), and 2,6‐di‐tert‐butyl‐4‐methoxyphenyl ( 2i ) 4‐vinylbenzoates were carried out in THF at –78°C with diphenylmethylpotassium and oligo(α‐methylstyryl)lithium and ‐dipotassium. No apparent polymerizations of 2a – 2e occurred probably due to the inherent side reactions such as nucleophilic attack of the anionic initiators toward the ester carbonyl groups. On the other hand, the polymerizations of 2f – 2i , the monomers possessing bulky aryl ester substituents, certainly proceeded to afford the polymers in quantitative yields. The molecular weight distribution (MWD) of poly( 2f ) was broad (Mw/Mn = 1.3–1.8), indicating partial side reactions during the course of the polymerization. By contrast, the resulting poly( 2g – 2i ) possessed narrow MWDs (Mw/Mn = 1.1) and predicted molecular weights based on the molar ratios between monomers to initiators. It was thus demonstrated that the steric hindrance around the ester carbonyl group was essential to obtain polymers having well‐defined chain structures via controlled anionic polymerizations of aryl 4‐vinylbenzoates. Novel tailored block copolymers, polyisoprene‐block‐poly( 2h ), poly( 2h )‐block‐polystyrene‐block‐poly( 2h ), poly(tert‐butyl methacrylate)‐block‐poly( 2h ), and poly( 2h )‐block‐poly(2‐isopropenylbenzoxazole) were synthesized by the sequential copolymerization of 2h and the corresponding comonomers. It was elucidated from the results of block copolymerization that anionic polymerizability of 2h was apparently higher than that of styrene because of the electron‐withdrawing effect of the COOAr substituent. 相似文献
994.
Toshihiro Yoshitake Akira Takeda Kensaku Ohki Yuko Inoue Takanori Yamawaki Saori Otsuka Minekatsu Akimoto Mitsuru Nemoto Yasuhito Shimakura Akio Sato 《The Journal of dermatology》2015,42(7):735-738
Finasteride is standard medical treatment for androgenetic alopecia; however, no large studies with 5 years or more of follow up have been performed in Japan. The authors followed Japanese men with androgenetic alopecia treated with finasteride for 5 years to evaluate long‐term treatment efficacy. Of 903 men treated with finasteride (1 mg/day), 801 patients were evaluated over 5 years by modified global photographic assessment. Although the proportion of improvement was high (99.4%), modified global photographic assessment scores after 5 years of treatment were lower in patients with more advanced disease as measured by the modified Norwood–Hamilton scale. After separating patients into “sufficient” and “insufficient” efficacy groups according to the modified global photographic assessment score after 5 years (scores ≥6 and <6, respectively), multivariate analysis showed that independent risk factors of insufficient efficacy were age at start of treatment of 40 years or more (P = 0.021) and classification on the modified Norwood–Hamilton scale (P < 0.001), whereas presence of stress at start of treatment was a negative predictor (P = 0.025). In conclusion, continuous finasteride treatment for 5 years improved androgenetic alopecia with sustained effect among Japanese. Younger age and less advanced disease at start of treatment were the key predictors of higher finasteride efficacy. 相似文献
995.
Yoshiko Ariji D.D.S. Ph.D. Jin-ichi Takahashi D.D.S. Osamu Matsui D.D.S. Ph.D. Tsuneichi Okano Ph.D. Munetaka Naitoh D.D.S. Ph.D. Hidemichi Yuasa D.D.S. Ph.D. Hiroto Iida D.D.S. Jiro Hasegawa D.D.S. Ph.D. Akira Senda D.D.S. Ph.D. Eiichiro Ariji D.D.S. Ph.D. 《Oral Radiology》1998,14(2):75-83
The aim of this study was to evaluate observer performance with a charge coupled device-based intraoral X-ray imaging system,
Pana Digital system, in comparison with conventional film-based radiography (Ektaspeed Plus). A total of 118 teeth mounted
in plaster were radiographed using both the Pana Digital system and conventional film. The occlusal and approximal surfaces
of the resultant images were evaluated by six observers in relation to the caries depth. For the verification of the caries
depth, the teeth surfaces were rated histologically by two examiners according to the same rating scores used for the X-ray
imaging assessment. The sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy
of the two image modalities were calculated together with Cohen's kappa values. No significant difference was found in any
diagnostic parameters at any thresholds between the two modalities. The Kappa values for the Pana Digital system showed relatively
lower levels than those of conventional film in occlusal caries assessment, whereas no apparent differences were found between
the two modalities in any scores of depth for approximal caries assessment. The results of the present study, in which there
was no discrepancy in diagnostic abilities, suggested that the Pana Digital system could play a useful role in clinical caries
diagnosis. 相似文献
996.
Yasuo Murai Takayuki Mizunari Ryo Takagi Yasuo Amano Sunao Mizumura Yuichi Komaba Seiji Okubo Shiro Kobayashi Akira Teramoto 《Clinical neurology and neurosurgery》2013
Background
Cerebral revascularization surgery (CRS) is increasingly recognized as an important component in the treatment of complex cerebral vascular disease and tumors. CRS requires that the incidence of perioperative neurological complications should be minimized, because CRS for ischemic disease is often not the goal of treatment, but rather a prophylactic surgery. CRS carries the risk of focal postoperative neurological deficits. Little has been established concerning mechanisms of post-CRS ischemia. We used 3.0-T diffusion-weighted magnetic resonance imaging (DWI) and magnetic resonance angiography (MRA) to analyze the incidence and mechanism of ischemic lesions.Methods
We studied the anterior circulation territory after 20 CRS procedures involving 33 vascular anastomosis procedures (13 double anastomoses and 7 single anastomoses) in 12 men and 8 women between June 2007 and October 2011. The operations included single or double superficial temporal artery–middle cerebral artery (STA–MCA) anastomosis to treat internal carotid artery/MCA occlusions or severe MCA stenosis. A combined STA–MCA anastomosis and indirect bypass were performed for moyamoya disease. Postoperative DWI and MRA were obtained in all patients between 24 and 96 h after surgery to detect thromboembolism, hypoperfusion, or procedural ischemic complications and vasospasms of the donor STA.Results
Follow-up DWI and MRA were carried out 1.8 ± 0.6 days after CRS (range, 1–4 days). Temporary occlusion time for anastomoses averaged 18.9 min (range, 16–32 min). Asymptomatic new hyperintensities occurred in the ipsilateral hemisphere of 2 patients on postoperative DWI (10% patients/6.0% anastomoses), and 1 moyamoya patient (5.0% patients/3.0% anastomoses) developed a symptomatic hyperintensity in the ipsilateral occipital lobe in response to the operation. Two abnormal small (<5 mm) cortical DWI lesions were caused by sacrifices of a small branch of the recipient MCA.Conclusion
This study is the first postoperative 3.0-T DWI study of CRS and related clinical events. The incidence of symptomatic postoperative DWI abnormalities was restricted to 1 moyamoya patient representing 5.0% of total patients and 3.0% anastomoses. Although some postoperative DWI abnormalities occurred, CRS was found to be safe with a low risk of symptomatic ischemia. 相似文献997.
Yukie Hirahara Ken Ichi Matsuda Hisao Yamada Akira Saitou Shinsuke Morisaki Keiko Takanami Joan M. Boggs Mitsuhiro Kawata 《Glia》2013,61(3):420-431
Estrogen exerts neuroprotective and promyelinating actions. The therapeutic effect has been shown in animal models of multiple sclerosis, in which the myelin sheath is specifically destroyed in the central nervous system. However, it remains unproven whether estrogen is directly involved in remyelination via the myelin producing cells, oligodendrocytes, or which estrogen receptors are involved. In this study, we found that the membrane‐associated estrogen receptor, the G protein‐coupled receptor 30 (GPR30), also known as GPER, was expressed in oligodendrocytes in rat spinal cord and corpus callosum. Moreover, GPR30 was expressed throughout oligodendrocyte differentiation and promyelinating stages in primary oligodendrocyte cultures derived from rat spinal cords and brains. To evaluate the role of signaling via GPR30 in promyelination, a specific agonist for GPR30, G1, was administered to a rat model of demyelination induced by cuprizone treatment. Histological examination of the corpus callosum with oligodendrocyte differentiation stage‐specific markers showed that G1 enhanced oligodendrocyte maturation in corpus callosum of cuprizone‐treated animals. It also enhanced oligodendrocyte ensheathment of dorsal root ganglion (DRG) neurons in co‐culture and myelination in cuprizone‐treated animals. This study is the first evidence that GPR30 signaling promotes remyelination by oligodendrocytes after demyelination. GPR30 ligands may provide a novel therapy for the treatment of multiple sclerosis. © 2012 Wiley Periodicals, Inc. 相似文献
998.
Masato Asahina David A. Low Christopher J. Mathias Yoshikatsu Fujinuma Akira Katagiri Yoshitaka Yamanaka Junichiro Shimada Anupama Poudel Satoshi Kuwabara 《Parkinsonism & related disorders》2013,19(5):560-562
AimA previous study on a small number of patients showed that low skin temperature of the hands, the so called “cold hands sign”, may be useful for distinguishing multiple system atrophy (MSA) from Parkinson's disease (PD). We have further investigated skin temperature of the hand in a larger number of patients.MethodsSkin temperature on the palm was measured in 50 MSA (11 MSA-P and 39 MSA-C patients) and 50 PD patients, and 25 normal healthy subjects.ResultsPalm skin temperature was significantly lower in MSA patients (32.0 ± 2.7 °C) than in controls (34.1 ± 0.9 °C, p = 0.0002), but was not different compared with the PD group (32.9 ± 1.8 °C, p = 0.06). Temperatures of <28 °C were observed in 3 MSA patients (6%) and none of the PD patients and controls. There was no significant difference in palm skin temperature between patients with and without orthostatic hypotension for each patient group, or between MSA-P and MSA-C patients.ConclusionThe cold hand (<28 °C) is a useful marker for distinguishing MSA from PD, but it is not common in MSA patients, and its sensitivity may be low for differentiating between MSA and PD. 相似文献
999.
Hirokazu Doi Takashi X. Fujisawa Chieko Kanai Haruhisa Ohta Hideki Yokoi Akira Iwanami Nobumasa Kato Kazuyuki Shinohara 《Journal of autism and developmental disorders》2013,43(9):2099-2113
This study investigated the ability of adults with Asperger syndrome to recognize emotional categories of facial expressions and emotional prosodies with graded emotional intensities. The individuals with Asperger syndrome showed poorer recognition performance for angry and sad expressions from both facial and vocal information. The group difference in facial expression recognition was prominent for stimuli with low or intermediate emotional intensities. In contrast to this, the individuals with Asperger syndrome exhibited lower recognition accuracy than typically-developed controls mainly for emotional prosody with high emotional intensity. In facial expression recognition, Asperger and control groups showed an inversion effect for all categories. The magnitude of this effect was less in the Asperger group for angry and sad expressions, presumably attributable to reduced recruitment of the configural mode of face processing. The individuals with Asperger syndrome outperformed the control participants in recognizing inverted sad expressions, indicating enhanced processing of local facial information representing sad emotion. These results suggest that the adults with Asperger syndrome rely on modality-specific strategies in emotion recognition from facial expression and prosodic information. 相似文献
1000.
Akira Nakashima Akira Ota Yoko S. Kaneko Keiji Mori Hiroshi Nagasaki Toshiharu Nagatsu 《Journal of neural transmission (Vienna, Austria : 1996)》2013,120(1):49-54
Postmortem brain biochemistry has revealed that the main symptom of movement disorder in Parkinson’s disease (PD) is caused by a deficiency in dopamine (DA) at the nerve terminals of degenerating nigro-striatal DA neurons in the striatum. Since tyrosine hydroxylase (TH) is the rate-limiting enzyme for the biosynthesis of DA, TH may play an important role in the disease process of PD. DA regulated by TH activity is thought to interact with α-synuclein protein, which results in intracellular aggregates called Lewy bodies and causes apoptotic cell death during the aging process. Human TH has several isoforms produced by alternative mRNA splicing, which may affect activation by phosphorylation of serine residues in the N-terminus of TH. The activity and protein level of TH are decreased to cause DA deficiency in the striatum in PD. However, the homo-specific activity (activity/enzyme protein) of TH is increased. This increase in TH homo-specific activity suggests activation by increased phosphorylation at the N-terminus of the TH protein for a compensatory increase in DA synthesis. We recently found that phosphorylation of the N-terminal portion of TH triggers proteasomal degradation of the enzyme to increase TH turnover. We propose a hypothesis that this compensatory activation of TH by phosphorylation in the remaining DA neurons may contribute to a further decrease in TH protein and activity in DA neurons in PD, causing a vicious circle of decreasing TH activity, protein level and DA contents. Furthermore, increased TH homo-specific activity leading to an increase in DA may cause toxic reactive oxygen species in the neurons to promote neurodegeneration. 相似文献