67 results on '"Hideaki Imai"'
Search Results
2. Treating Pulsatile Exophthalmos in Child with Minimally Invasive Approach and Custom-made Titanium Mesh Plate
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Yuta Moriwaki, MD, Yoko Tomioka, PhD, Hideaki Imai, PhD, Takuya Iida, PhD, Shuji Yamashita, PhD, Koji Kanayama, PhD, Naoaki Iwamoto, MD, and Mutsumi Okazaki, PhD
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Surgery ,RD1-811 - Abstract
Summary:. Orbital roof fracture is a relatively rare trauma. In most cases, surgical intervention is not needed since the fracture is slight. However, invasive surgical procedures are inevitable once pulsatile exophthalmos occurs if vision impairment is to be avoided. We report our rare experience of orbital roof fracture in a child with pulsatile exophthalmos. Good reconstruction of the anterior cranial base was achieved using a custom-made titanium mesh and a minimally invasive approach. A 3-year-old girl who had been diagnosed with subdural hematoma, brain contusion, and fracture of the right orbital roof caused by facial bruising underwent emergent external decompression by coronal skin incision and a transcranial approach on the same day as the trauma. Cranioplasty using autologous frozen bone in the same approach was performed 103 days posttrauma, but this was followed by pulsatile exophthalmos. After recovering from critical stage, the girl was brought to our department for reconstruction of the anterior base. Risk of vision impairment was also one reason for reconstruction, but the neurosurgeon hesitated to approach the region using a coronal approach considering the possibility of infection in the frozen autologous bone. Through cross-team discussion, reconstruction using a subeyebrow incision was performed with a custom-made titanium mesh plate. Pulsatile exophthalmos completely disappeared. Pulsatile exophthalmos is a very rare but serious complication that carries a risk of vision impairment. By applying a custom-made titanium mesh plate, precise reconstruction was enabled with minimal invasiveness and low risk.
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- 2019
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3. Five-Year Stroke Risk and Its Predictors in Asymptomatic Moyamoya Disease: Asymptomatic Moyamoya Registry (AMORE)
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Satoshi Kuroda, Shusuke Yamamoto, Takeshi Funaki, Miki Fujimura, Hiroharu Kataoka, Tomohito Hishikawa, Jun Takahashi, Hidenori Endo, Tadashi Nariai, Toshiaki Osato, Nobuhito Saito, Norihiro Sato, Emiko Hori, Yoichi M. Ito, Susumu Miyamoto, Motoki Inaji, Kenichi Morita, Daisuke Maruyama, Jyoji Nakagawara, Naoki Hashimura, Eika Hamano, Koji Iihara, Nobuo Hashimoto, Kaori Honjo, Hirohiko Nakamura, Daina Kashiwazaki, Hideaki Imai, Satoru Miyawaki, Hiroki Hongo, Kazumichi Yoshida, Takayuki Kikuchi, Yohei Mineharu, Makoto Isozaki, Kenichiro Kikuta, Yoshio Araki, Fumiaki Kanamori, Isao Date, Junichi Ono, Toshio Machida, Mitsuhito Mase, Hiroyuki Katano, Koji Yamaguchi, Takakazu Kawamata, Teiji Tominaga, Haruto Uchino, Kikutaro Tokairin, Masaki Ito, Kiyohiro Houkin, Kohei Chida, Kuniaki Ogasawara, Izumi Nagata, Nobutaka Horie, Hidehiro Oka, Toshihiro Kumabe, Yoshiaki Itoh, Takato Abe, Koichi Oki, Shinichi Takahashi, and Norihiro Suzuki
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Advanced and Specialized Nursing ,Neurology (clinical) ,Cardiology and Cardiovascular Medicine - Abstract
Background: Long-term outcomes are unknown in patients with asymptomatic moyamoya disease. In this report, we aimed to clarify their 5-year risk of stroke and its predictors. Methods: We are conducting a multicenter, prospective cohort study (Asymptomatic Moyamoya Registry) in Japan. Participants were eligible if they were 20 to 70 years, had bilateral or unilateral moyamoya disease, experienced no episodes suggestive of TIA and stroke; and were functionally independent (modified Rankin Scale score 0–1). Demographic and radiological information was collected at enrollment. In this study, they are still followed up for 10 years. In this interim analysis, we defined the primary end point as a stroke occurring during a 5-year follow-up period. Independent predictors for stroke were also determined, using a stratification analysis method. Results: Between 2012 and 2015, we enrolled 109 patients, of whom 103 patients with 182 involved hemispheres completed the 5-year follow-up. According to the findings on DSA and MRA, 143 hemispheres were judged as moyamoya disease and 39 hemispheres as questionable manifestations (isolated middle cerebral artery stenosis). The patients with questionable hemispheres were significantly older, more often male, and more frequently had hypertension than those with moyamoya hemisphere. Moyamoya hemispheres developed 7 strokes, including 6 hemorrhagic and 1 ischemic stroke, during the first 5 years. The annual risk of stroke was 1.4% per person, 0.8% per hemisphere, and 1.0% per moyamoya hemisphere. Independent predictor for stroke was Grade-2 choroidal anastomosis (hazard ratio, 5.05 [95% CI, 1.24–20.6]; P =0.023). Furthermore, microbleeds (hazard ratio, 4.89 [95% CI, 1.13-21.3]; P =0.0342) and Grade-2 choroidal anastomosis (hazard ratio, 7.05 [95% CI, 1.62–30.7]; P =0.0093) significantly predicted hemorrhagic stroke. No questionable hemispheres developed any stroke. Conclusions: The hemispheres with asymptomatic moyamoya disease may carry a 1.0% annual risk of stroke during the first 5 years, the majority of which are hemorrhagic stroke. Grade-2 choroidal anastomosis may predict stroke, and the microbleeds and Grade-2 choroidal anastomosis may carry the risk for hemorrhagic stroke. Registration: URL: https://www.clinicaltrials.gov ; Unique identifier: UMIN000006640.
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- 2023
4. Multiple Spinal Syphilitic Gummas Diagnosed by Postoperative Histopathology and Antibiotic Responsiveness: A Case Report
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Manabu Niimura and Hideaki Imai
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Surgical resection ,medicine.medical_specialty ,medicine.drug_class ,business.industry ,spinal syphilitic gumma ,Antibiotics ,Case Report ,surgical resection ,medicine.disease ,Surgery ,Neurosyphilis ,differential diagnosis ,antibiotic treatment ,medicine ,neurosyphilis ,Histopathology ,Differential diagnosis ,business - Abstract
Neurosyphilis is an infection of the central nervous system by Treponema pallidum. Gummatous neurosyphilis, especially spinal syphilitic gumma, is an exceedingly rare manifestation and may be misdiagnosed as other tumors due to its rarity. A 42-year-old man with a medical history of treatment for syphilis presented with rapidly progressive leg paralysis, leg sensory disturbance, and bladder and rectal disturbance. Spinal MRI demonstrated an intradural extramedullary lesion strongly compressing the spinal cord at the T6/7 level, which was accompanied with dural tail sign and perilesional meningeal thickening at the T6–T8 levels. Small intradural extramedullary lesions were also detected at the T1 and T8 levels. Serological and cerebrospinal fluid examinations for syphilis were both positive. In the treatment of spinal syphilitic gumma, the decompression of the spinal cord by lesionectomy followed by postoperative antibiotic treatment is considered to be an optimal procedure in patients with rapid progression of neurological deterioration. In the present case, the symptomatic main lesion that was compressing the thoracic cord was excised by surgery and analyzed by histopathological examination, and another small asymptomatic lesion was resolved by postoperative antibiotic treatment. Spinal syphilitic gumma was diagnosed using both histopathological findings of the surgically resected lesion and another residual lesion that was resolved by postoperative antibiotic treatment.
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- 2021
5. Research on the Characteristic Evaluation of Electromagnetic Shielding Material for Aircraft Windows
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Masahiko Hinatase, Naruto Yonemoto, Hideaki Imai, Kazuyuki Oguri, and Tomohiro Isshiki
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Materials science ,Acoustics ,Electromagnetic shielding - Published
- 2021
6. EPEN-27. Epigenetic dissection of spinal ependymomas (SP-EPN) separates tumors with and withoutNF2 mutation
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Sina Neyazi, Erika Yamazawa, Catena Kresbach, Genta Nagae, Alicia Eckhardt, Takayoshi Umeda, Lara Pohl, Kenji Tatsuno, Ceren Saygi, Taijun Hana, Malik Alawi, Phyo Kim, Mario M Dorostkar, Fumi Higuchi, Abigail K Suwala, Toshihiro Takami, Annika Wefers, Yuta Nakanishi, Leonille Schweizer, Keisuke Takai, Lara Engertsberger, Takashi Komori, Theresa Mohme, Hirokazu Takami, Martin Mynarek, Masashi Nomura, Karin Lamszus, Akitake Mukasa, Lan Kluwe, Shunsaku Takayanagi, Andreas von Deimling, Kazuhiko Ishii, Martin Benesch, Hideaki Imai, Matija Snuderl, Stephan Frank, Koichi Ichimura, Christian Hagel, Viktor F Mautner, Stefan Rutkowski, Shota Tanaka, Hiroyuki Aburatani, Saito Nobuhito, and Ulrich Schüller
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Cancer Research ,Oncology ,Neurology (clinical) - Abstract
Ependymomas encompass multiple, clinically relevant tumor types based on localization, genetic alterations, and epigenetic and transcriptomic profiles. Tumors belonging to the methylation class of spinal ependymoma (SP-EPN) represent the most common intramedullary neoplasms in children and adults. However, molecular data of SP-EPN are scarce, and clear treatment recommendations are lacking. The only known recurrent genetic events in SP-EPN are loss of chromosome 22q and NF2 mutations. Yet, it remains unclear whether SP-EPN with germline or sporadic NF2 mutations or with NF2 wild type status differ clinically or molecularly. To provide a comprehensive molecular profile of SP-EPN, we integrated epigenetic, genomic, transcriptomic, and histological analyses of up to 237 cases. Clustering of methylation data revealed two distinct molecular SP-EPN subtypes. The distribution of NF2 mutated cases differed significantly across these subtypes (p
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- 2022
7. Differences in Clinical Features among Different Onset Patterns in Moyamoya Disease
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Kenta Ohara, Hirofumi Nakatomi, Yudai Hirano, Shogo Dofuku, Satoru Miyawaki, Satoshi Koizumi, Hideaki Imai, Daiichiro Ishigami, Hideaki Ono, Hiroki Hongo, Nobuhito Saito, and Yu Teranishi
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medicine.medical_specialty ,Carotid arteries ,Disease ,Review ,Asymptomatic ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,0302 clinical medicine ,Internal medicine ,medicine ,risk factors ,cerebrovascular events ,Severe stenosis ,Moyamoya disease ,hemorrhagic onset ,asymptomatic moyamoya disease ,medicine.diagnostic_test ,business.industry ,Magnetic resonance imaging ,General Medicine ,medicine.disease ,Collateral circulation ,Natural history ,onset pattern ,ischemic onset ,natural history ,Cardiology ,Medicine ,medicine.symptom ,business ,moyamoya disease ,030217 neurology & neurosurgery - Abstract
Moyamoya disease is characterized by severe stenosis at the ends of the bilateral internal carotid arteries and the development of collateral circulation. The disease is very diverse in terms of age at onset, onset patterns, radiological findings, and genetic phenotypes. The pattern of onset is mainly divided into ischemic and hemorrhagic onsets. Recently, the opportunity to identify asymptomatic moyamoya disease, which sometimes manifests as nonspecific symptoms such as headache and dizziness, through screening with magnetic resonance imaging has been increasing. Various recent reports have investigated the associations between the clinical features of different onset patterns of moyamoya disease and the corresponding imaging characteristics. In this article, we have reviewed the natural history, clinical features, and imaging features of each onset pattern of moyamoya disease.
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- 2021
8. Stem cell implants show promise in chronic traumatic brain injury
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Laroslav Zinkevych, Dai Chida, Alan Weintraub, Yasuaki Karasawa, Bijan Nejadnik, Daniel C. Lu, Hajime Nakamura, David O. Okonkwo, Masahito Kawabori, Takehiko Kaneko, Neil E. Schwartz, Susan Paadre, Jefferson W. Chen, Achal S. Achrol, Benjamin M. Frishberg, Steven C. Cramer, Takao Yasuhara, Douglas Kondziolka, Jun Suenaga, Peter McAllister, Anthony H. Stonehouse, Gary K. Steinberg, Damien Bates, Ihor Semeniv, Hideaki Imai, and R. Mark Richardson
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0301 basic medicine ,Randomization ,Physical Injury - Accidents and Adverse Effects ,Traumatic brain injury ,Population ,Clinical Trials and Supportive Activities ,Clinical Sciences ,MEDLINE ,Traumatic Brain Injury (TBI) ,Bioinformatics ,Mean difference ,Article ,Cell therapy ,03 medical and health sciences ,Cellular and Molecular Neuroscience ,0302 clinical medicine ,Injury - Trauma - (Head and Spine) ,Clinical Research ,Medicine ,In patient ,Adverse effect ,education ,Traumatic Head and Spine Injury ,education.field_of_study ,Neurology & Neurosurgery ,business.industry ,Neurosciences ,Interim analysis ,medicine.disease ,Brain Disorders ,030104 developmental biology ,Anesthesia ,Injury (total) Accidents/Adverse Effects ,Cognitive Sciences ,Neurology (clinical) ,Patient Safety ,Stem cell ,Injury - Traumatic brain injury ,business ,030217 neurology & neurosurgery - Abstract
ObjectiveTo determine whether chronic motor deficits secondary to traumatic brain injury (TBI) can be improved by implantation of allogeneic modified bone marrow–derived mesenchymal stromal/stem cells (SB623).MethodsThis 6-month interim analysis of the 1-year double-blind, randomized, surgical sham–controlled, phase 2 Stem Cell Therapy for Traumatic Brain Injury (STEMTRA) trial (NCT02416492) evaluated safety and efficacy of the stereotactic intracranial implantation of SB623 in patients with stable chronic motor deficits secondary to TBI. Patients in this multicenter trial (n = 63) underwent randomization in a 1:1:1:1 ratio to 2.5 × 106, 5.0 × 106, or 10 × 106 SB623 cells or control. Safety was assessed in patients who underwent surgery (n = 61), and efficacy was assessed in the modified intent-to-treat population of randomized patients who underwent surgery (n = 61; SB623 = 46, control = 15).ResultsThe primary efficacy endpoint of significant improvement from baseline of Fugl-Meyer Motor Scale score at 6 months for SB623-treated patients was achieved. SB623-treated patients improved by (least square [LS] mean) 8.3 (standard error 1.4) vs 2.3 (standard error 2.5) for control at 6 months, the LS mean difference was 6.0 (95% confidence interval 0.3–11.8, p = 0.040). Secondary efficacy endpoints improved from baseline but were not statistically significant vs control at 6 months. There were no dose-limiting toxicities or deaths, and 100% of SB623-treated patients experienced treatment-emergent adverse events vs 93.3% of control patients (p = 0.25).ConclusionsSB623 cell implantation appeared to be safe and well tolerated, and patients implanted with SB623 experienced significant improvement from baseline motor status at 6 months compared to controls.ClinicalTrials.gov Identifier:NCT02416492.Classification of EvidenceThis study provides Class I evidence that implantation of SB623 was well tolerated and associated with improvement in motor status.
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- 2021
9. Association Between the Onset Pattern of Adult Moyamoya Disease and Risk Factors for Stroke
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Yudai Hirano, Kenta Ohara, Satoru Miyawaki, Hirofumi Nakatomi, Yu Teranishi, Hiroki Hongo, Nobuhito Saito, Hideaki Imai, and Shogo Dofuku
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Adult ,Male ,Pediatrics ,medicine.medical_specialty ,03 medical and health sciences ,0302 clinical medicine ,Risk Factors ,0502 economics and business ,medicine ,Humans ,Moyamoya disease ,Stroke ,Retrospective Studies ,Advanced and Specialized Nursing ,medicine.diagnostic_test ,business.industry ,05 social sciences ,Brain ,Magnetic resonance imaging ,Cerebral Arteries ,Middle Aged ,medicine.disease ,Magnetic Resonance Imaging ,Natural history ,050211 marketing ,Female ,Neurology (clinical) ,Moyamoya Disease ,Cardiology and Cardiovascular Medicine ,business ,030217 neurology & neurosurgery ,Magnetic Resonance Angiography - Abstract
Background and Purpose: Few previous studies have comprehensively explored the relationship between the onset pattern of adult moyamoya disease and risk factors for stroke. We performed a retrospective analysis focusing on risk factors for stroke and related findings on magnetic resonance imaging/angiography with respect to the pattern of disease onset. We also examined whether risk factors for stroke were associated with an increased risk for symptomization in asymptomatic patients. Methods: A total of 178 adult patients with moyamoya disease (asymptomatic, n=84; ischemic, n=71; hemorrhagic, n=23) at the University of Tokyo Hospital from 2000 to 2018 were included in this study. Data pertaining to patient background and magnetic resonance imaging findings were analyzed retrospectively. In the asymptomatic group, the effects of stroke-associated risk factors on symptom onset were analyzed. Results: Comparisons among the 3 groups revealed no significant difference in the frequency of risk factors for stroke. The proportion of patients with magnetic resonance imaging/angiography findings indicating anterior choroidal artery anastomosis or microbleeds was significantly higher in the hemorrhagic group than in the asymptomatic or ischemic group. Among asymptomatic patients, the hazard ratios for symptomization with hypertension and dyslipidemia were 6.69 ([95% CI, 1.23–36.4] P =0.028) and 8.14 ([95% CI, 1.46–45.2] P =0.017), respectively. Conclusions: The development of anterior choroidal artery anastomosis and microbleeds on magnetic resonance imaging/angiography was significantly associated with hemorrhagic onset. Hypertension and dyslipidemia may increase the risk of cerebrovascular events in asymptomatic patients, and thus, early intervention to these factors may be important.
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- 2020
10. Comprehensive investigation of RNF213 nonsynonymous variants associated with intracranial artery stenosis
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Yu Teranishi, Hiroyuki Ishiura, Masahiro Shimizu, Shinichi Yagi, Wei Qu, Hideaki Imai, Jun Yoshimura, Tsuneo Shimizu, Shoji Tsuji, Jun Mitsui, Shinichi Morishita, Koichiro Doi, Hiroki Hongo, Nobuhito Saito, Atsushi Okano, Hirofumi Nakatomi, Satoru Miyawaki, and Hideaki Ono
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Adult ,Male ,Nonsynonymous substitution ,medicine.medical_specialty ,dbSNP ,Adolescent ,Genotype ,Ubiquitin-Protein Ligases ,Mutation, Missense ,lcsh:Medicine ,Constriction, Pathologic ,030204 cardiovascular system & hematology ,Polymorphism, Single Nucleotide ,Gastroenterology ,Article ,Young Adult ,03 medical and health sciences ,0302 clinical medicine ,Polymorphism (computer science) ,Internal medicine ,medicine ,Humans ,Missense mutation ,Genetic Predisposition to Disease ,Moyamoya disease ,lcsh:Science ,Alleles ,Genetic Association Studies ,Aged ,Adenosine Triphosphatases ,Aged, 80 and over ,Multidisciplinary ,Molecular medicine ,business.industry ,lcsh:R ,Genetic Variation ,Intracranial Artery ,Sequence Analysis, DNA ,Middle Aged ,medicine.disease ,Stenosis ,Amino Acid Substitution ,Risk factors ,Female ,lcsh:Q ,Intracranial Arterial Diseases ,business ,030217 neurology & neurosurgery - Abstract
Intracranial artery stenosis (ICAS) is the most common cause of ischemic stroke worldwide. RNF213 single nucleotide variant c.14429G > A (p.Arg4810Lys, rs112735431) was recently reported to be associated with ICAS in East Asians. However, the disease susceptibility of other RNF213 variants has not been clarified. This study comprehensively investigated ICAS-associated RNF213 variants in a pool of 168 Japanese ICAS patients and 1,194 control subjects. We found 138 nonsynonymous germline variants by target resequencing of all coding exons in RNF213. Association study between ICAS patients and control subjects revealed that only p.Arg4810Lys had significant association with ICAS (P = 1.5 × 10–28, odds ratio = 29.3, 95% confidence interval 15.31–56.2 [dominant model]). Fourteen of 138 variants were rare variants detected in ICAS patients not harboring p.Arg4810Lys variant. Two of these rare variants (p.Cys118Arg and p.Leu2356Phe) consistent with variants previously reported in moyamoya disease patients characterized by stenosis of intracranial artery and association with RNF213, and three rare variants (p.Ser193Gly, p.Val1817Leu, and p.Asp3329Tyr) were found neither in control subjects and Single Nucleotide Polymorphism Database. The present findings may improve our understanding of the genetic background of intracranial artery stenosis.
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- 2020
11. Precision Medicine for Ischemic Cerebrovascular Diseases
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Nobuhito Saito, Satoru Miyawaki, and Hideaki Imai
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medicine.medical_specialty ,business.industry ,Medicine ,Surgery ,Neurology (clinical) ,business ,Intensive care medicine ,Precision medicine - Published
- 2018
12. Correction to: RNF213 p.Arg4810Lys Heterozygosity in Moyamoya Disease Indicates Early Onset and Bilateral Cerebrovascular Events
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Masahiro Shimizu, Yu Teranishi, Hirofumi Nakatomi, Yudai Hirano, Daisuke Shimada, Hiroki Hongo, Nobuhito Saito, Hideaki Imai, Hideaki Ono, Shogo Dofuku, Kenta Ohara, Daiichiro Ishigami, Satoru Miyawaki, Masafumi Segawa, and Satoshi Koizumi
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Loss of heterozygosity ,Pediatrics ,medicine.medical_specialty ,business.industry ,General Neuroscience ,MEDLINE ,Medicine ,Neurology (clinical) ,Moyamoya disease ,Cardiology and Cardiovascular Medicine ,business ,medicine.disease ,Early onset - Published
- 2021
13. EPCO-01. MOLECULAR PROFILING OF SPINAL CORD EPENDYMOMA
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Fumi Higuchi, Erika Yamazawa, Kazuha Kugasawa, Hideaki Imai, Tsukasa Koike, Yoshihiro Kushihara, Taijun Hana, Reiko Matsuura, Toshihiro Takami, Shohei Nambu, Kazuhiko Ishii, Hirokazu Takami, Hiroyuki Aburatani, Phyo Kim, Nobuhito Saito, Shota Tanaka, Yuta Nakanishi, Genta Nagae, Akitake Mukasa, Takashi Komori, Shunsaku Takayanagi, Takayoshi Umeda, Keisuke Takai, and Masashi Nomura
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Ependymoma ,Cancer Research ,Spinal Cord Ependymoma ,Methylation ,26th Annual Meeting & Education Day of the Society for Neuro-Oncology ,Ribosomal RNA ,Biology ,Spinal cord ,medicine.disease ,medicine.anatomical_structure ,Oncology ,DNA methylation ,Cancer research ,medicine ,Neurology (clinical) ,Epigenetics ,Epigenomics - Abstract
BACKGROUND Ependymomas are currently classified into 9 subgroups by DNA methylation profiles. Although spinal cord ependymoma (SP-EPN) is distinct from other tumors, diversity within SP-EPN is still unclear. Here, we used transcriptomic and epigenomic profiles to investigate the diversity among Japanese SP-EPN cases. MATERIALS AND METHODS We analyzed 57 SP-EPN patients (32 males and 25 females, aged from 18 to 78 years, median: 52), including two cases of neurofibromatosis type 2, five cases of grade 3 (WHO grade). We obtained transcriptome (RNA-seq) and DNA methylation (Infinium Methylation EPIC array) data from fresh frozen specimens of SP-EPN resected at the University of Tokyo Hospital and our collaborative groups. RESULTS Three cases had a previous intracranial ependymoma operation. Hierarchical clustering of the DNA methylation data showed that these three cases of intracranial origin as a different cluster from spinal origin. The 45 grade 2 spinal ependymoma showed a relatively homogenous methylation pattern. However, the methylation status of HOX gene cluster regions is compatible with the segment of origin, which reflects the cells of origins are derived after the determination of segment identity. RNA sequencing of 57 cases revealed two subgroups within grade 2. Gene ontology analysis of differentially expressed genes suggested the difference in metabolic state such as rRNA translation and mitochondrial respiration between the two expression subgroups. CONCLUSION Epigenetic analysis indicated the accurate body segment origin of SP-EPN. We observed that metabolic states could divide grade 2 spinal cord ependymoma into 2 subgroups and will present the relationship to clinicopathological information.
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- 2021
14. Genetic analysis of intracranial major artery stenosis: Analysis of moyamoya disease associated gene RNF213
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Nobuhito Saito, Satoru Miyawaki, and Hideaki Imai
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medicine.medical_specialty ,Stenosis ,Major artery ,business.industry ,Internal medicine ,medicine ,Cardiology ,General Medicine ,Moyamoya disease ,medicine.disease ,business ,Genetic analysis ,Gene - Published
- 2017
15. Wall-to-lumen ratio of intracranial arteries measured by indocyanine green angiography
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Nobuhito Saito, Hiroshi Oyama, Toki Saito, Daichi Nakagawa, Hideaki Imai, Masaaki Shojima, Taichi Kin, Masanori Yoshino, Seiji Nomura, and Hirofumi Nakatomi
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medicine.medical_specialty ,vascular wall ,medicine.medical_treatment ,Lumen (anatomy) ,030204 cardiovascular system & hematology ,intracranial artery ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,In vivo ,Medical imaging ,Medicine ,medicine.diagnostic_test ,business.industry ,Intracranial Artery ,General Medicine ,wall-to-lumen ratio ,Microsurgery ,medicine.disease ,normal ,Stenosis ,chemistry ,Angiography ,Original Article ,Radiology ,business ,Operating microscope ,Indocyanine green ,indocyanine green angiography ,030217 neurology & neurosurgery - Abstract
Background: The wall-to-lumen ratio (WLR) is an important parameter in vascular medicine because it indicates the character of vascular wall as well as the degree of stenosis. Despite the advances in medical imaging technologies, it is still difficult to measure the thin-walled normal intracranial arteries, and the reports on the WLR of normal intracranial artery are limited. It might be possible to calculate the WLR using the indocyanine green (ICG) angiography, which is used to observe intracranial vessels during microsurgery. Purpose: To evaluate the WLR of normal intracranial arteries using ICG angiography. Materials and Methods: From the three cases in which ICG angiography was recorded with a ruler during microsurgery, 20 measurement points were chosen for the analysis. The ICG was injected intravenously with a dose of 0.2 mg/kg, and the vessels were inspected at high magnification using an operating microscope equipped with near-infrared illumination system. The vessel outer diameter and the luminal diameter were measured using the images before and after the ICG arrival based on the pixel ratio method using a ruler as reference, respectively. The WLR was calculated as 0.5 × (vessel outer diameter − vessel luminal diameter). Results: The WLR (mean ± standard deviation) of normal intracranial arteries was 0.086 ± 0.022. The WLR tended to be high in small arteries. Conclusion: The WLR of normal intracranial arteries calculated using ICG angiography was consistent with the WLR reported in the previous reports based on human autopsy.
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- 2016
16. Treatment of ischemic neuronal death by introducing brain-derived neurotrophic factor mRNA using polyplex nanomicelle
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Keiji Itaka, Nobuhito Saito, Hirofumi Nakatomi, Kazunori Kataoka, Satoshi Uchida, Hideaki Imai, and Yuta Fukushima
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Biophysics ,Ischemia ,Hippocampus ,Bioengineering ,02 engineering and technology ,Pharmacology ,Hippocampal formation ,Biomaterials ,03 medical and health sciences ,Neurotrophic factors ,medicine ,Animals ,RNA, Messenger ,030304 developmental biology ,Brain-derived neurotrophic factor ,0303 health sciences ,Messenger RNA ,Cell Death ,business.industry ,Brain-Derived Neurotrophic Factor ,021001 nanoscience & nanotechnology ,medicine.disease ,Rats ,medicine.anatomical_structure ,nervous system ,Mechanism of action ,Mechanics of Materials ,Ceramics and Composites ,medicine.symptom ,0210 nano-technology ,business ,Astrocyte - Abstract
Ischemic neuronal death causes serious lifelong neurological deficits; however, there is no proven effective treatment that can prevent neuronal death after the ischemia. We investigated the feasibility of mRNA therapeutics for preventing the neuronal death in a rat model of transient global ischemia (TGI). By intraventricular administration of mRNA encoding brain-derived neurotrophic factor (BDNF) using a polymer-based carrier, polyplex nanomicelle, the mRNA significantly increased the survival rate of hippocampal neurons after TGI, with a rapid rise of BDNF in the hippocampus. Interestingly, mRNA administration on Day 2 after TGI provided significantly better survival rate than the administration immediately after TGI. Eventually, dosing twice on Day 2 and 5 exerted long-term therapeutic effects, which were confirmed by a Y-maze behavioral test demonstrating improved spatial memory compared with untreated rats on Day 20. Immunohistochemical analysis showed that astrocytes were chief targets of the BDNF mRNA-loaded nanomicelles, suggesting that the augmented BDNF secretion from astrocytes creates a supportive microenvironment for the neurons to tolerate changes caused by ischemic stresses, and terminate the process of progressive neuronal death after the ischemic attack. Overall, the unique mechanism of action of mRNA therapeutics provide a promising approach for preventing ischemic neuronal death.
- Published
- 2021
17. The outcome of a surgical protocol based on ischemia overprotection in large and giant aneurysms of the anterior cerebral circulation
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Katsushige Watanabe, Takaaki Miyagishima, Taichi Kin, Hirofumi Nakatomi, Nobuhito Saito, Yuhei Yoshimoto, and Hideaki Imai
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Adult ,Carotid Artery Diseases ,Male ,medicine.medical_specialty ,Microsurgery ,Middle Cerebral Artery ,Anterior Cerebral Artery ,Decompression ,medicine.medical_treatment ,Bypass ,Ischemia ,Clinical Neurology ,Neurosurgical Procedures ,030218 nuclear medicine & medical imaging ,Brain Ischemia ,03 medical and health sciences ,Cerebral circulation ,0302 clinical medicine ,medicine.artery ,Occlusion ,medicine ,Humans ,Perforating artery ,Motor evoked potential ,Aged ,Intracavernous aneurysm ,business.industry ,Glasgow Outcome Scale ,Intracranial Aneurysm ,General Medicine ,Clipping (medicine) ,Giant/large cerebral aneurysm ,Middle Aged ,medicine.disease ,Surgical Instruments ,Surgery ,Cerebral Angiography ,Treatment Outcome ,Bypass surgery ,Anesthesia ,Cerebrovascular Circulation ,Original Article ,Female ,Neurology (clinical) ,Internal carotid artery ,business ,030217 neurology & neurosurgery - Abstract
Aiming to define the optimal treatment of large and giant aneurysms (LGAs) in the anterior circulation, we present our surgical protocol and patient outcome. A series of 42 patients with intracavernous LGAs (n = 16), paraclinoid (C2) LGAs (n = 17), and peripheral (middle cerebral artery—MCA or anterior cerebral artery—ACA) LGAs (n = 9) were treated after bypass under motor evoked potential (MEP) monitoring. Preoperatively, three categories of ischemic tolerance during internal carotid artery (ICA) occlusion were defined on conventional angiography: optimal, suboptimal, and insufficient collaterals. Accordingly, three types of bypass: low flow (LFB), middle flow (MFB) and high flow (HFB) were applied for the cases with optimal, suboptimal, and insufficient collaterals, respectively. Outcome was evaluated by the Glasgow Outcome Scale (GOS). All patients had excellent GOS score except one, who suffered a major ischemic stroke immediately after surgery for a paraclinoid lesion. Forty-one patients were followed up for 87.1 ± 40.1 months (range 13–144 months). Intracavernous LGAs were all treated by proximal occlusion with bypass surgery. Of paraclinoid LGA patients, 15 patients had direct clipping under suction decompression and other 2 patients with recurrent aneurysms had ICA (C2) proximal clipping with HFB. MEP monitoring guided for temporary clipping time and clip repositioning, observing significant MEP changes for up to 6 min duration. Of 9 peripheral LGAs patients 7 MCA LGAs had reconstructive clipping (n = 4) or trapping (n = 3) with bypass including LFB in 3 cases, MFB in 1 and HFB in 1. Two ACA LGAs had clipping (n = 1) or trapping (n = 1) with A3-A3 bypass. The applied protocol provided excellent results in intracavernous, paraclinoid, and peripheral thrombosed LGAs of the anterior circulation.
- Published
- 2016
18. Dorsal Forebrain-Specific Deficiency of Reelin-Dab1 Signal Causes Behavioral Abnormalities Related to Psychiatric Disorders
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Kenji Sakimura, Toshio Terashima, Masaki Ogata, Yu Katsuyama, Hideaki Imai, Hirotaka Shoji, Tsuyoshi Miyakawa, Yoshiteru Kagawa, and Yuji Owada
- Subjects
Male ,0301 basic medicine ,Reflex, Startle ,medicine.medical_specialty ,Cell Adhesion Molecules, Neuronal ,Cognitive Neuroscience ,Hippocampus ,Nerve Tissue Proteins ,Motor Activity ,Mice ,03 medical and health sciences ,Cellular and Molecular Neuroscience ,0302 clinical medicine ,Conditional gene knockout ,medicine ,Animals ,Reelin ,Maze Learning ,Psychiatry ,Mice, Knockout ,Extracellular Matrix Proteins ,Memory Disorders ,Behavior, Animal ,biology ,Cerebellar ataxia ,business.industry ,Mental Disorders ,Serine Endopeptidases ,Immobility Response, Tonic ,Fear ,medicine.disease ,DAB1 ,Adaptation, Physiological ,Mice, Inbred C57BL ,Disease Models, Animal ,Reelin Protein ,030104 developmental biology ,nervous system ,Schizophrenia ,Forebrain ,Exploratory Behavior ,biology.protein ,Cerebellar atrophy ,medicine.symptom ,business ,030217 neurology & neurosurgery ,Signal Transduction - Abstract
Reelin-Dab1 signaling is involved in brain development and neuronal functions. The abnormalities in the signaling through either reduction of Reelin and Dab1 gene expressions or the genomic mutations in the brain have been reported to be associated with psychiatric disorders. However, it has not been clear if the deficiency in Reelin-Dab1 signaling is responsible for symptoms of the disorders. Here, to examine the function of Reelin-Dab1 signaling in the forebrain, we generated dorsal forebrain-specific Dab1 conditional knockout mouse (Dab1 cKO) and performed a behavioral test battery on the Dab1 cKO mice. Although conventional Dab1 null mutant mice exhibit cerebellar atrophy and cerebellar ataxia, the Dab1 cKO mice had normal cerebellum and showed no motor dysfunction. Dab1 cKO mice exhibited behavioral abnormalities, including hyperactivity, decreased anxiety-like behavior, and impairment of working memory, which are reminiscent of symptoms observed in patients with psychiatric disorders such as schizophrenia and bipolar disorder. These results suggest that deficiency of Reelin-Dab1 signal in the dorsal forebrain is involved in the pathogenesis of some symptoms of human psychiatric disorders.
- Published
- 2016
19. Rat white matter injury model induced by endothelin-1 injection: technical modification and pathological evaluation
- Author
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Hideaki Imai, Nobuhito Saito, Hideaki Ono, Satoru Miyawaki, and Hirofumi Nakatomi
- Subjects
0301 basic medicine ,Pathology ,medicine.medical_specialty ,Time Factors ,Internal capsule ,Stilbamidines ,Ischemia ,Poison control ,Functional Laterality ,Rats, Sprague-Dawley ,White matter ,Lesion ,Amyloid beta-Protein Precursor ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,lacunar infarction ,Internal Capsule ,Leukoencephalopathies ,Glial Fibrillary Acidic Protein ,medicine ,Animals ,Swimming ,Neurologic Examination ,Hydroxystilbamidine ,Endothelin-1 ,medicine.diagnostic_test ,business.industry ,rat model ,General Neuroscience ,Magnetic resonance imaging ,General Medicine ,Ectodysplasins ,medicine.disease ,Magnetic Resonance Imaging ,Rats ,Disease Models, Animal ,030104 developmental biology ,medicine.anatomical_structure ,chemistry ,Gliosis ,white matter injury ,histopathology ,retrograde tracing ,medicine.symptom ,business ,Locomotion ,Psychomotor Performance ,030217 neurology & neurosurgery - Abstract
White matter injury is an important cause of functional disability of the brain. We comprehensively analyzed a modified endothelin-1 (ET-1) injection-induced white matter injury model in the rat which is very valuable for investigating the underlying mechanisms of subcortical ischemic stroke. ET-1 was stereotactically injected into the internal capsule of the rat. To avoid complications with leakage of ET-1 into the lateral ventricle, the safest trajectory angle to the target was established. Rats with white matter injury were extensively evaluated for structural changes and functional sequelae, using motor function tests, magnetic resonance (MR) imaging, histopathology evolution, volume estimation of the lesion, and neuroanatomical identification of affected neurons using the retrograde tracer hydroxystilbamidine. Optimization of the trajectory of the ET-1 injection needle provided excellent survival rate. MR imaging visualized the white matter injury 2 days after surgery. Motor function deficit appeared temporarily after the operation. Histological studies confirmed damage of axons and myelin sheaths followed by inflammatory reaction and gliosis similar to lacunar infarction, with lesion volume of less than 1% of the whole brain. Hydroxystilbamidine injected into the lesion revealed wide spatial distribution of the affected neuronal population. Compared with prior ET 1 injection models, this method induced standardized amount of white matter damage and temporary motor function deficit in a reproducible and safe manner. The present model is valuable for studying the pathophysiology of not only ischemia, but a broader set of white matter damage conditions in the lissencephalic brain.
- Published
- 2016
20. Surgical management for a huge presacral teratoma and a meningocele in an adult with Currarino triad: a case report
- Author
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Kazushige Kawai, Tetsuo Ushiku, Keisuke Hata, Toshiaki Tanaka, Manabu Kaneko, Koji Murono, Sakae Tanaka, Hideaki Imai, Kazuhito Sasaki, Nobuhito Saito, Takeshi Nishikawa, Hiroshi Kobayashi, Kensuke Otani, Shigenobu Emoto, Hiroaki Nozawa, and Masako Ikemura
- Subjects
medicine.medical_specialty ,business.industry ,Presacral teratoma ,lcsh:Surgery ,Currarino triad ,Case Report ,lcsh:RD1-811 ,Meningocele ,Posterior approach ,Surgery ,03 medical and health sciences ,Triad (sociology) ,0302 clinical medicine ,030220 oncology & carcinogenesis ,medicine ,Presacral mass ,030211 gastroenterology & hepatology ,business - Abstract
Background The Currarino triad is a rare hereditary syndrome comprising anorectal malformation, sacral bony defect, and presacral mass. Most of the patients are diagnosed during infancy. Case presentation A 44-year-old man was diagnosed with Currarino triad, with a huge presacral teratoma and meningocele. One-stage surgery via posterior approach was successful. Conclusions Treatment of the presacral mass in the Currarino triad, diagnosed in adulthood, is challenging. Multidisciplinary management and detailed planning before surgery are important for a satisfactory outcome.
- Published
- 2017
21. Smaller outer diameter of atherosclerotic middle cerebral artery associated with RNF213 c.14576G>A Variant (rs112735431)
- Author
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Akira Kunimatsu, Harushi Mori, Hideaki Imai, Satoru Miyawaki, Yuki Shinya, Hideaki Ono, Hiroki Hongo, Nobuhito Saito, and Hirofumi Nakatomi
- Subjects
medicine.medical_specialty ,Outer diameter ,magnetic resonance imaging (MRI) ,030204 cardiovascular system & hematology ,Neurovascular: Original Article ,03 medical and health sciences ,0302 clinical medicine ,Internal medicine ,medicine.artery ,Occlusion ,medicine ,genetics ,intracranial artery stenosis ,remodeling ,medicine.diagnostic_test ,RNF213 ,Variant type ,business.industry ,Magnetic resonance imaging ,medicine.disease ,Atherosclerosis ,Stenosis ,Middle cerebral artery ,Cardiology ,Surgery ,Neurology (clinical) ,Intracranial Atherosclerosis ,business ,030217 neurology & neurosurgery ,Ring Finger Protein 213 - Abstract
Background Intracranial atherosclerosis (ICAS) involves diverse histologies and several remodeling patterns. Ring finger protein 213 (RNF213) c.14576G>A variant (rs112735431), recently reported to be associated with ICAS, may be linked with negative remodeling (outer diameter - reducing morphological alteration) of intracranial arteries. This study investigated the outer diameter of atherosclerotic middle cerebral artery (MCA). Methods Patients with unilateral atherosclerotic MCA stenosis/occlusion were enrolled in this single-hospital-based case-control study at The University of Tokyo Hospital. The patients were divided into two groups by the presence of RNF213 c.14576G>A (variant group and wild-type group) and the outer diameter of the MCA was measured with high-resolution magnetic resonance imaging. Results Twenty-eight patients with the wild type and 19 patients with the variant type were included. The outer diameter of the stenotic side MCA was smaller in the variant group than in the wild-type group (P = 8.3 × 10-6). The outer diameter of the normal side MCA was also smaller in the variant group than in the wild-type group (P = 5.2 × 10-3). The ratio of stenotic side to normal side was also smaller in the variant group than in the wild-type group (P = 1.5 × 10-5). Conclusions This study indicates that RNF213 c.14576G>A is associated with negative remodeling of ICAS.
- Published
- 2017
22. Pre- and Intraoperative Brain Functional Mapping in Brain Tumor Surgery
- Author
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Hirofumi Nakatomi, Akira Kunimatsu, Nobuhito Saito, Akitake Mukasa, Toki Saito, Masahiro Shin, Taichi Kin, Masanori Yoshino, Hideaki Imai, Masaaki Shojima, Daichi Nakagawa, and Hiroshi Oyama
- Subjects
medicine.medical_specialty ,Functional mapping ,business.industry ,Medicine ,Surgery ,Neurology (clinical) ,Radiology ,business ,Brain tumor surgery - Published
- 2014
23. Treating Pulsatile Exophthalmos in Child with Minimally Invasive Approach and Custom-made Titanium Mesh Plate
- Author
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Naoaki Iwamoto, Mutsumi Okazaki, Shuji Yamashita, Yuta Moriwaki, Hideaki Imai, Yoko Tomioka, Takuya Iida, and Koji Kanayama
- Subjects
medicine.medical_specialty ,Exophthalmos ,business.industry ,medicine.medical_treatment ,lcsh:Surgery ,Pulsatile flow ,Brain Contusion ,Case Report ,lcsh:RD1-811 ,030230 surgery ,medicine.disease ,Cranioplasty ,Surgery ,03 medical and health sciences ,0302 clinical medicine ,Hematoma ,030220 oncology & carcinogenesis ,Coronal plane ,medicine ,Neurosurgery ,medicine.symptom ,business ,Complication - Abstract
Summary:. Orbital roof fracture is a relatively rare trauma. In most cases, surgical intervention is not needed since the fracture is slight. However, invasive surgical procedures are inevitable once pulsatile exophthalmos occurs if vision impairment is to be avoided. We report our rare experience of orbital roof fracture in a child with pulsatile exophthalmos. Good reconstruction of the anterior cranial base was achieved using a custom-made titanium mesh and a minimally invasive approach. A 3-year-old girl who had been diagnosed with subdural hematoma, brain contusion, and fracture of the right orbital roof caused by facial bruising underwent emergent external decompression by coronal skin incision and a transcranial approach on the same day as the trauma. Cranioplasty using autologous frozen bone in the same approach was performed 103 days posttrauma, but this was followed by pulsatile exophthalmos. After recovering from critical stage, the girl was brought to our department for reconstruction of the anterior base. Risk of vision impairment was also one reason for reconstruction, but the neurosurgeon hesitated to approach the region using a coronal approach considering the possibility of infection in the frozen autologous bone. Through cross-team discussion, reconstruction using a subeyebrow incision was performed with a custom-made titanium mesh plate. Pulsatile exophthalmos completely disappeared. Pulsatile exophthalmos is a very rare but serious complication that carries a risk of vision impairment. By applying a custom-made titanium mesh plate, precise reconstruction was enabled with minimal invasiveness and low risk.
- Published
- 2019
24. Genetic Variant RNF213 c.14576G>A in Various Phenotypes of Intracranial Major Artery Stenosis/Occlusion
- Author
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Masahiro Shimizu, Akitake Mukasa, Shinichi Yagi, Hideaki Imai, Nobuhito Saito, Hideaki Ono, Satoru Miyawaki, Tsuneo Shimizu, and Hirofumi Nakatomi
- Subjects
Male ,medicine.medical_specialty ,Ubiquitin-Protein Ligases ,Population ,Aneurysm ,Asian People ,Japan ,Risk Factors ,Internal medicine ,Occlusion ,medicine ,Humans ,Moyamoya disease ,education ,Alleles ,Adenosine Triphosphatases ,Advanced and Specialized Nursing ,Intracerebral hemorrhage ,education.field_of_study ,business.industry ,Incidence ,Case-control study ,Genetic Variation ,Odds ratio ,medicine.disease ,Surgery ,Stenosis ,Case-Control Studies ,Cardiology ,Female ,Neurology (clinical) ,Moyamoya Disease ,Cardiology and Cardiovascular Medicine ,business - Abstract
Background and Purpose— Recently, we reported a common genetic variant, ring finger protein 213 ( RNF213 ) c.14576G>A variant, a susceptibility gene for moyamoya disease (MMD), among patients with intracranial major artery stenosis/occlusion (ICASO) in a selected Japanese population. The aim of this 2-center–based case–control study was to confirm our previous finding in a larger population. Methods— Study participants were recruited from The University of Tokyo Hospital and Kanto Neurosurgical Hospital. The occurrence rate of c.14576G>A variant was investigated in 323 patients, 22 with definite MMD, 8 with unilateral MMD, 84 with ICASO in the absence of MMD (non-MMD ICASO), 34 with extracranial carotid atherosclerosis, 44 with cerebral aneurysm, 21 with intracerebral hemorrhage, and 110 control subjects. Results— RNF213 c.14576G>A variant was found in 1.8% (2/110) of the normal control group and had significant associations with definite MMD ( P P =0.0001; odds ratio, 54.0; 95% confidence interval, 7.5–386.8), and non-MMD ICASO ( P Conclusions— A particular subset of patients with various phenotypes of ICASO has a common genetic variant, RNF213 c.14576G>A, indicating that RNF213 c.14576G>A variant is a high-risk allele for ICASO.
- Published
- 2013
25. Virtual Reality Neurosurgical Simulation using Computer Graphics
- Author
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Masaaki Shojima, Hirofumi Nakatomi, Taichi Kin, Nobuhito Saito, Akitake Mukasa, Masanori Yoshino, Hideaki Imai, Daichi Nakagawa, Masahiro Shin, Hiroshi Oyama, and Shunya Hanakita
- Subjects
Computer graphics ,business.industry ,Computer graphics (images) ,Medicine ,Surgery ,Neurology (clinical) ,Virtual reality ,business - Published
- 2013
26. Symptomatic Recurrence of Intracranial Arterial Dissections
- Author
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Akira Teraoka, Hirofumi Nakatomi, Takafumi Ide, Kazuo Tsutsumi, Nobuhito Saito, Hideaki Ono, Chifumi Kitanaka, Keisuke Ueki, Tomohiro Inoue, Hideaki Imai, and Yuhei Yoshimoto
- Subjects
Adult ,Male ,medicine.medical_specialty ,Subarachnoid hemorrhage ,Adolescent ,Infarction ,Cohort Studies ,Young Adult ,Aneurysm ,Secondary Prevention ,medicine ,Humans ,Young adult ,Child ,Pathological ,Aged ,Aged, 80 and over ,Advanced and Specialized Nursing ,Arterial dissection ,business.industry ,Intracranial Aneurysm ,Middle Aged ,medicine.disease ,Surgery ,Radiography ,Aortic Dissection ,Treatment Outcome ,Female ,Histopathology ,Neurology (clinical) ,Cardiology and Cardiovascular Medicine ,business ,Follow-Up Studies ,Cohort study - Abstract
Background and Purpose— The frequency and pattern of symptomatic recurrence of spontaneous intracranial arterial dissection (IAD) are unknown. Methods— A follow-up study of 143 patients (85 men, 58 women; mean age, 50.7 [7–83] years) with spontaneous IADs at The University of Tokyo and affiliated hospitals from 1980 to 2000 was conducted. Tissue samples of IAD vessels obtained from 13 patients at various intervals from onset were also examined histologically. Results— With a mean follow-up of 8.2 years, symptomatic recurrence occurred in 47 patients (33%). Of 37 cases initially presenting with hemorrhage, 35 developed hemorrhagic recurrence with a mean interval of 4.8 days, and 2 developed nonhemorrhagic recurrences after 21 and 85 months, respectively. Of 10 patients initially presenting with nonhemorrhagic symptoms, 1 developed hemorrhagic recurrence 4 days later, and 9 developed nonhemorrhagic recurrences with a mean interval of 8.6 months. Histopathologically, the affected vessels in the acute stage of hemorrhage (days 0–6) demonstrated insufficient granulation formation within the pseudolumen, followed by marked intimal thickening around the pseudolumen and recanalizing vessel formation in the late stage (>day 30). In the late stage of brain ischemia, subintimal and subadventitial hemorrhage accompanied with intimal thickening was observed. Conclusions— These data indicate that IAD is a disease carrying a relatively high risk of symptomatic recurrence, apparently occurring in 3 phases and patterns: early hemorrhagic recurrence, late nonhemorrhagic recurrence, and chronic fusiform aneurysm transformation. Knowledge of this triphasic recurrence and corresponding histopathological characteristics help determine the treatment and follow-up strategy for IAD patients.
- Published
- 2013
27. Identification of a Genetic Variant Common to Moyamoya Disease and Intracranial Major Artery Stenosis/Occlusion
- Author
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Satoru Miyawaki, Akitake Mukasa, Hirofumi Nakatomi, Nobuhito Saito, Hideaki Imai, and Shunsaku Takayanagi
- Subjects
Adult ,Male ,medicine.medical_specialty ,Ubiquitin-Protein Ligases ,Central nervous system disease ,Aneurysm ,Asian People ,Japan ,Risk Factors ,Internal medicine ,Occlusion ,medicine ,Humans ,Genetic Predisposition to Disease ,Moyamoya disease ,Stroke ,Aged ,Adenosine Triphosphatases ,Advanced and Specialized Nursing ,Vascular disease ,business.industry ,Genetic Variation ,Middle Aged ,medicine.disease ,Surgery ,Stenosis ,Case-Control Studies ,Cardiology ,Female ,Cerebral Arterial Diseases ,Neurology (clinical) ,Neurosurgery ,Moyamoya Disease ,Cardiology and Cardiovascular Medicine ,business - Abstract
Background and Purpose— The c.14576G>A variant in ring finger protein 213 (RNF213) was recently identified as a susceptibility gene variant for moyamoya disease (MMD). The occurrence of c.14576G>A variant was evaluated in patients with intracranial major artery stenosis/occlusion (ICASO) without signs of MMD (non-MMD ICASO), as well as in patients with MMD and other cerebrovascular diseases as controls. Methods— This single-hospital–based case-control study was completed in 7 months (from October 2011–April 2012) at Department of Neurosurgery, The University of Tokyo Hospital. The occurrence of c.14576G>A variant was analyzed in 41 patients with non-MMD ICASO, in 48 with MMD, in 21 with cervical disease, in 61 with cerebral aneurysm, and in 25 normal subjects. Results— Nine of 41 patients (21.9%) with non-MMD ICASO and 41 of 48 (85.4%) with MMD had the c.14576G>A variant. One of 61 patients (1.6%) with cerebral aneurysm and no patients with cervical disease or normal subjects had the variant. Comparison of each phenotype group with the normal subjects showed that presence of c.14576G>A variant had significant associations with MMD (odds ratio [OR], 292.8; 95% confidence interval [CI], 15.4–5153.0; P Conclusions— The present study indicates that a particular subset of Japanese patients with non-MMD ICASO has a genetic variant associated with MMD. Therefore, we propose the existence of a new entity of ICASO caused by the c.14576G>A variant in RNF213.
- Published
- 2012
28. Successful surgical strategy for a cervical hemangioblastoma: Case report
- Author
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Hideaki Imai, Daichi Nakagawa, Hirofumi Nakatomi, Tomomasa Kondo, Nobuhito Saito, Masanori Yoshino, Seiji Nomura, Kazuhiko Ishii, Junichi Ohya, Taichi Kin, Hirotaka Chikuda, and Satoru Miyawaki
- Subjects
medicine.medical_specialty ,indocyanine green ,hemangioblastoma ,three-dimensional computer graphics ,temporary arterial occlusion ,medicine.medical_treatment ,Dura mater ,Anterior spinal artery ,03 medical and health sciences ,0302 clinical medicine ,Hemangioblastoma ,medicine.artery ,medicine ,Syrinx (medicine) ,Corpectomy ,business.industry ,spinal cord ,medicine.disease ,Spinal cord ,Surgical Neurology International: Spine ,Spinal hemangioblastoma ,Surgery ,medicine.anatomical_structure ,030220 oncology & carcinogenesis ,Thyrocervical trunk ,Anterior approach ,Neurology (clinical) ,business ,030217 neurology & neurosurgery - Abstract
Background Hemangioblastomas are hypervascular lesions and hence their surgical management is challenging. In particular, if complete resection is to be attained, all feeding and draining vessels must be occluded. Although most intramedullary spinal cord tumors are treated utilizing a posterior approach, we describe an anterior surgical strategy for resection of an intramedullary cervical hemangioblastoma. Case description A 36-year-old female with a spinal hemangioblastoma located in the anterior cervical spinal cord presented with a long-standing history of motor weakness of the right upper extremity. Magnetic resonance imaging revealed a large multilevel extensive syrinx and a focal intramedullary enhanced tumor at the C6 level. Angiography showed that the main feeder to the tumor was the left radicular artery (C8), which originated from the thyrocervical trunk, penetrated the dura mater, and branched both rostrally and caudally into the anterior spinal artery (ASA). Three-dimensional computer graphic images showed the tumor was located in the anterior part of the spinal cord, adjacent to and supplied by the ASA. The planned anterior surgical approach involved a total corpectomy of C6 and partial corpectomies of C5 and C7. The tumor was entirely removed despite multiple adhesions, and was successfully freed from the ASA. Patency of the ASA was confirmed utilizing intraoperative indocyanine green videoangiography. Intraoperatively, no monitoring changes were encountered. The pathological diagnosis was of a hemangioblastoma. No postoperative deficit occurred. Conclusions An anterior approach for the resection of an anteriorly located intramedullary spinal hemangioblastomas was successfully accomplished in this case.
- Published
- 2016
29. Dynamic changes in the gene expression of zebrafish Reelin receptors during embryogenesis and hatching period
- Author
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Hideaki Imai, Toshio Terashima, Wataru Shoji, Yu Katsuyama, Masahiko Hibi, Satoshi Kikkawa, and Yoshihiro Oomiya
- Subjects
biology ,Cell Biology ,Anatomy ,DAB1 ,biology.organism_classification ,Cell biology ,Laminar organization ,nervous system ,biology.protein ,Reelin ,Signal transduction ,Tectum ,Receptor ,Brain morphogenesis ,Zebrafish ,Developmental Biology - Abstract
The brain morphology of vertebrates exhibits huge evolutionary diversity, but one of the shared morphological features unique to vertebrate brain is laminar organization of neurons. Because the Reelin signal plays important roles in the development of the laminar structures in mammalian brain, investigation of Reelin signal in lower vertebrates will give some insights into evolution of vertebrate brain morphogenesis. Although zebrafish homologues of Reelin, the ligand, and Dab1, a cytoplasmic component of the signaling pathway, have been reported, the Reelin receptor molecules of zebrafish are not reported yet. Here, we sought cDNA sequence of zebrafish homologue of the receptors, vldlr and apoer2, and examined their expression patterns by in situ hybridization. Developmental gene expression pattern of reelin, dab1, vldlr, and apoer2 in the central nervous system of zebrafish was compared, and their remarkable expression was detected in the developing laminar structures, such as the tectum and the cerebellum, and also non-laminated structures, such as the pallium. The Reelin receptors exhibited different spatial and temporal gene expression. These results suggest a possibility that duplication and subsequent functional diversity of Reelin receptors contributed to the morphological and functional evolution of vertebrate brain.
- Published
- 2012
30. CyberKnife Radiosurgery for Spinal Cord Arteriovenous Malformations
- Author
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Hiroshi K. Inoue, Masanori Yoshino, Nobuhito Saito, Taichi Kin, Keisuke Takai, Hideaki Imai, and Kazuhiko Ishii
- Subjects
medicine.medical_specialty ,medicine.anatomical_structure ,business.industry ,medicine ,CyberKnife Radiosurgery ,Radiology ,business ,Spinal cord - Published
- 2012
31. Constitutive Reactive Oxygen Species Generation from Autophagosome/Lysosome in Neuronal Oxidative Toxicity
- Author
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Hideaki Imai, Ni Hou, Toshiyuki Takeuchi, Nobuhito Saito, Chisato Kubota, Yuhei Yoshimoto, and Seiji Torii
- Subjects
Male ,Mitochondrial ROS ,Autophagosome ,Programmed cell death ,Neurotoxins ,Intracellular Space ,Glutamic Acid ,Mitochondrion ,Biology ,Biochemistry ,Cell Line ,Rats, Sprague-Dawley ,Mice ,Molecular Basis of Cell and Developmental Biology ,Phagosomes ,Lysosome ,Autophagy ,medicine ,Animals ,Molecular Biology ,Phagosome ,Neurons ,chemistry.chemical_classification ,Reactive oxygen species ,Cell Biology ,Rats ,Cell biology ,medicine.anatomical_structure ,chemistry ,Molecular Probes ,Lysosomes ,Reactive Oxygen Species ,Oxidation-Reduction - Abstract
Reactive oxygen species (ROS) are involved in several cell death processes, including cerebral ischemic injury. We found that glutamate-induced ROS accumulation and the associated cell death in mouse hippocampal cell lines were delayed by pharmacological inhibition of autophagy or lysosomal activity. Glutamate, however, did not stimulate autophagy, which was assessed by a protein marker, LC3, and neither changes in organization of mitochondria nor lysosomal membrane permeabilization were observed. Fluorescent analyses by a redox probe PF-H(2)TMRos revealed that autophagosomes and/or lysosomes are the major sites for basal ROS generation in addition to mitochondria. Treatments with inhibitors for autophagy and lysosomes decreased their basal ROS production and caused a burst of mitochondrial ROS to be delayed. On the other hand, attenuation of mitochondrial activity by serum depletion or by high cell density culture resulted in the loss of both constitutive ROS production and an ROS burst in mitochondria. Thus, constitutive ROS production within mitochondria and lysosomes enables cells to be susceptible to glutamate-induced oxidative cytotoxicity. Likewise, inhibitors for autophagy and lysosomes reduced neural cell death in an ischemia model in rats. We suggest that cell injury during periods of ischemia is regulated by ROS-generating activity in autophagosomes and/or lysosomes as well as in mitochondria.
- Published
- 2010
32. A case of cerebral amyloid angiopathy mimicking a brain tumor
- Author
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Yuhei Yoshimoto, Kenichi Sugawara, Shogo Ishiuchi, Hideaki Imai, Kaie Kagoshima, and Youichi Nakazato
- Subjects
Pathology ,medicine.medical_specialty ,business.industry ,Brain tumor ,Medicine ,Cerebral amyloid angiopathy ,business ,medicine.disease - Published
- 2009
33. Experimental Model of Lacunar Infarction in the Gyrencephalic Brain of the Miniature Pig
- Author
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Kenjiro Konno, Hidekazu Hata, Yuhei Yoshimoto, Nobuhito Saito, Takeo Aoki, Kuniaki Takata, Yukitaka Tanaka, Takaaki Miyagishima, Chisato Kubota, Sandra Puentes, and Hideaki Imai
- Subjects
Brain Infarction ,medicine.medical_specialty ,Pathology ,Internal capsule ,Neurology ,Miniature pig ,Swine ,Pyramidal Tracts ,Infarction ,Occlusion ,medicine ,Animals ,Advanced and Specialized Nursing ,biology ,business.industry ,Brain ,Evoked Potentials, Motor ,biology.organism_classification ,medicine.disease ,Magnetic Resonance Imaging ,Pathophysiology ,Anterior choroidal artery ,Disease Models, Animal ,Corticospinal tract ,Swine, Miniature ,Neurology (clinical) ,Cardiology and Cardiovascular Medicine ,business - Abstract
Background and Purpose— Lacunar infarction accounts for 25% of ischemic strokes, but the pathological characteristics have not been investigated systematically. A new experimental model of lacunar infarction in the miniature pig was developed to investigate the pathophysiological changes in the corticospinal tract from the acute to chronic phases. Methods— Thirty-five miniature pigs underwent transcranial surgery for permanent anterior choroidal artery occlusion. Animals recovered for 24 hours (n=7), 2 (n=5), 3 (n=2), 4 (n=2), 6 (n=1), 7 (n=7), 8 (n=2), and 9 days (n=1), 2 weeks (n=2), 4 weeks (n=3), and more than 4 weeks (n=3). Neurology, electrophysiology, histology, and MRI were performed. Seven additional miniature pigs underwent transient anterior choroidal artery occlusion to study muscle motor-evoked potentials and evaluate corticospinal tract function during transient anterior choroidal artery occlusion. Results— The protocol had a 91.4% success rate in induction of internal capsule infarction 286±153 mm 3 (mean±SD). Motor-evoked potentials revealed the presence of penumbral tissue in the internal capsule after 6 to 15 minutes anterior choroidal artery occlusion. Total neurological deficit scores of 15.0 (95% CI, 13.5 to 16.4) and 3.4 (0.3 to 6.4) were recorded for permanent anterior choroidal artery occlusion and sham groups, respectively ( P P Conclusions— This new model of lacunar infarction induces a reproducible infarct in subcortical white matter with a measurable functional deficit and evidence of penumbral tissue acutely.
- Published
- 2008
34. Recurrent cerebral aneurysm formation and rupture within a short period due to invasive aspergillosis of the nasal sinus; pathological analysis of the catastrophic clinical course
- Author
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Yuki, Shinya, Satoru, Miyawaki, Hirofumi, Nakatomi, Atsushi, Okano, Hideaki, Imai, Masahiro, Shin, Kazuya, Sato, Takeyuki, Tsuchida, Toshihiro, Hayashi, Yasuo, Terao, Satoe, Numakura, Teppei, Morikawa, Junji, Shibahara, Shu, Kikuta, Kenji, Kondo, Keita, Tatsuno, Harushi, Mori, Akira, Kunimatsu, Shoji, Tsuji, and Nobuhito, Saito
- Subjects
Male ,Antifungal Agents ,Recurrence ,Aspergillosis ,Humans ,Intracranial Aneurysm ,Case Report ,Aneurysm, Ruptured ,Sinusitis ,Aged - Abstract
Destructive infiltration of invasive fungal sinusitis can easily occur into the central nervous system (CNS). Cerebral aneurysms associated with fungal infection are highly vulnerable to rupture, and can frequently and rapidly take a serious clinical course. We experienced a patient who twice developed cerebral aneurysm followed by rupture due to invasive fugal sinusitis. This 77-year-old man was admitted for progressive bilateral visual disturbance, which was initially treated as idiopathic hypertrophic pachymeningitis. The patient subsequently suffered subarachnoid hemorrhage (SAH) twice in only 12 days. Both SAH originated from different newly formed cerebral aneurysms. Trapping was performed for both ruptured aneurysms. Pathological examination of the resected aneurysms indicated the presence of fungi determined to be Aspergillus. This Aspergillus infection was also discovered inside the frontal sinus by endoscopic biopsy, so a regimen of antifungal agents was instituted. Prolonged antifungal therapy caused renal impairment, which ultimately led to the patient’s death. Autopsy detected no mycotic infiltration of the major cerebral arteries, except for the 2 ruptured cerebral aneurysms. However, prolonged mycosis of the CNS, such as in the deep part in the falx cerebri and in the small veins proximal to the tentorium cerebelli, was observed, indicating that mycosis invading the cranium is refractory even to long-term administration of antifungal agents. The present case strongly suggests that urgent and proactive definitive diagnosis is essential to successfully treat invasive paranasal sinus aspergillosis. If infiltration of the CNS is suspected, early surgical resection and antifungal therapy must be initiated immediately.
- Published
- 2015
35. Transplanted microvascular endothelial cells promote oligodendrocyte precursor cell survival in ischemic demyelinating lesions
- Author
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Sandra Puentes, Masahiko Mikuni, Yuhei Yoshimoto, Masae Naruse, Keiya Iijima, Koji Shibasaki, Masashi Kurachi, Hideaki Imai, and Yasuki Ishizaki
- Subjects
Male ,endocrine system ,Pathology ,medicine.medical_specialty ,Internal capsule ,Cell Survival ,Biochemistry ,Brain Ischemia ,White matter ,Rats, Sprague-Dawley ,Cellular and Molecular Neuroscience ,In vivo ,Precursor cell ,Medicine ,Animals ,Remyelination ,business.industry ,Stem Cells ,Endothelial Cells ,Oligodendrocyte ,Rats ,Transplantation ,Oligodendroglia ,medicine.anatomical_structure ,Apoptosis ,Immunology ,Microvessels ,cardiovascular system ,business ,Demyelinating Diseases - Abstract
We previously showed that transplantation of brain microvascular endothelial cells (MVECs) greatly stimulated remyelination in the white matter infarct of the internal capsule (IC) induced by endothelin-1 injection and improved the behavioral outcome. In the present study, we examined the effect of MVEC transplantation on the infarct volume using intermittent magnetic resonance image and on the behavior of oligodendrocyte lineage cells histochemically. Our results in vivo show that MVEC transplantation reduced the infarct volume in IC and apoptotic death of oligodendrocyte precursor cells (OPCs). These results indicate that MVECs have a survival effect on OPCs, and this effect might contribute to the recovery of the white matter infarct. The conditioned-medium from cultured MVECs reduced apoptosis of cultured OPCs, while the conditioned medium from cultured fibroblasts did not show such effect. These results suggest a possibility that transplanted MVECs increased the number of OPCs through the release of humoral factors that prevent their apoptotic death. Identification of such humoral factors may lead to the new therapeutic strategy against ischemic demyelinating diseases.
- Published
- 2015
36. Repeated de novo aneurysm formation after anastomotic surgery: Potential risk of genetic variant RNF213 c.14576G>A
- Author
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Satoru Miyawaki, Tomohiro Inoue, Gakushi Yoshikawa, Yuta Fukushima, Seiichiro Shimizu, Hideaki Imai, Kazuo Tsutsumi, and Nobuhito Saito
- Subjects
medicine.medical_specialty ,RNF213 ,Potential risk ,business.industry ,Genetic variants ,Case Report ,De novo aneurysm ,Anastomosis ,medicine.disease ,internal carotid artery occlusion ,Surgery ,de novo aneurysm ,external carotid artery-internal carotid artery anastomosis ,medicine ,cardiovascular system ,Neurology (clinical) ,Internal carotid artery occlusion ,Moyamoya disease ,cardiovascular diseases ,business ,Complication ,moyamoya disease - Abstract
Background: De novo aneurysm formation after intracranial anastomotic surgery is a relatively rare complication with fewer than 20 reported cases, and the mechanism is still unclear. Case Description: A 63-year-old male treated for symptomatic internal carotid artery occlusion developed de novo aneurysms twice after anastomoses first of the superficial temporal artery-middle cerebral artery and second of the external carotid artery-radial artery-middle cerebral artery over a 10-year period. The first de novo aneurysm was successfully resected with pathological diagnosis of true aneurysm. The second de novo aneurysm thrombosed naturally after gradual growth. Genetic testing of the patient revealed the c.14576G>A (p.R4859K) variant in ring finger protein 213, which is a susceptibility gene for moyamoya disease. Conclusions: This genetic variant was probably involved in the repeated de novo aneurysm formation, and this case represents a rare phenotype of the genetic variant.
- Published
- 2015
37. Cilostazol Attenuates Gray and White Matter Damage in a Rodent Model of Focal Cerebral Ischemia
- Author
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Chisato Kubota, Fumiaki Honda, Hideaki Imai, Tatsuya Shimizu, Mari Fukunaga, Makoto Ishikawa, and Nobuhito Saito
- Subjects
Male ,medicine.medical_specialty ,Time Factors ,Ischemia ,Tetrazoles ,Infarction ,Brain Ischemia ,Rats, Sprague-Dawley ,White matter ,Internal medicine ,Animals ,Medicine ,Stroke ,Advanced and Specialized Nursing ,Models, Statistical ,business.industry ,Brain ,medicine.disease ,Immunohistochemistry ,Magnetic Resonance Imaging ,Axons ,Cilostazol ,Rats ,Perfusion ,Disease Models, Animal ,Neuroprotective Agents ,medicine.anatomical_structure ,Cerebral blood flow ,Cerebrovascular Circulation ,Anesthesia ,Cerebral hemisphere ,Cardiology ,Neurology (clinical) ,Cardiology and Cardiovascular Medicine ,business ,Platelet Aggregation Inhibitors ,medicine.drug - Abstract
Background and Purpose— To evaluate whether delayed treatment with the antiplatelet agent cilostazol reduces the volume of infarction in the gray and white matter in a rodent model of permanent focal cerebral ischemia and to explore the mechanism of the neuroprotective effect in vivo. Methods— Cilostazol (30 or 50 mg/kg) or vehicle was administered by gavage 30 minutes and 4 hours after the induction of cerebral ischemia by permanent occlusion of the left middle cerebral artery (MCA). Animals were euthanized 24 hours after MCA occlusion, and the volume of gray matter damage was evaluated by quantitative histopathology. Axonal damage was determined with amyloid precursor protein immunohistochemistry. Dynamic susceptibility contrast MRI was used to assess regional cerebral blood volume (CBV) and cerebral blood flow (CBF). Results— Treatment with the higher dose of cilostazol (50 mg/kg) significantly reduced the volume of gray matter damage and axonal damage in the cerebral hemisphere by 45.0% ( P P P Conclusions— Treatment with cilostazol significantly reduced the gray and white matter damage associated with permanent focal ischemia. Cilostazol improved CBV and CBF in the peri-infarct area. The major action of cilostazol is to increase perfusion in the ischemic penumbra.
- Published
- 2006
38. Ebselen Protects Both Gray and White Matter in a Rodent Model of Focal Cerebral Ischemia
- Author
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Hideaki Imai, H. Masayasu, D. I. Graham, Deborah Dewar, and I.M. Macrae
- Subjects
Azoles ,Male ,Pathology ,medicine.medical_specialty ,Ischemia ,Isoindoles ,medicine.disease_cause ,Neuroprotection ,Antioxidants ,Brain Ischemia ,Rats, Sprague-Dawley ,Central nervous system disease ,White matter ,chemistry.chemical_compound ,Organoselenium Compounds ,medicine ,Animals ,Infusions, Intravenous ,Neurons ,Advanced and Specialized Nursing ,business.industry ,Ebselen ,Brain ,Infarction, Middle Cerebral Artery ,medicine.disease ,Axons ,Oligodendrocyte ,Rats ,Disease Models, Animal ,Oligodendroglia ,Oxidative Stress ,Neuroprotective Agents ,medicine.anatomical_structure ,chemistry ,Immunohistochemistry ,Lipid Peroxidation ,Neurology (clinical) ,Cardiology and Cardiovascular Medicine ,business ,Oxidative stress ,DNA Damage - Abstract
Background and Purpose — The neuroprotective efficacy of an intravenous formulation of the antioxidant ebselen has been comprehensively assessed with specific regard to conventional quantitative histopathology, subcortical axonal damage, neurological deficit, and principal mechanism of action. Methods — Transient focal ischemia (2 hours of intraluminal thread-induced ischemia with 22 hours of reperfusion) was induced in the rat. Ebselen (1 mg/kg bolus plus 1 mg/kg per hour IV) or vehicle was administered at the start of reperfusion and continued to 24 hours. Neurological deficit was assessed 24 hours after ischemia. Gray matter damage was evaluated by quantitative histopathology. Axonal damage was determined with amyloid precursor protein immunohistochemistry used as a marker of disrupted axonal flow and Tau-1 immunohistochemistry to identify oligodendrocyte pathology. Oxidative damage was determined by 8-hydroxy-2′-deoxyguanosine (8-OHdG) and 4-hydroxynonenal (4-HNE) immunohistochemistry. Results — Ebselen significantly reduced the volume of gray matter damage in the cerebral hemisphere (by 53.6% compared with vehicle, P P P P P P Conclusions — Delayed (2-hour) treatment with intravenous ebselen significantly reduced gray and white matter damage and neurological deficit associated with transient ischemia. The reduction in tissue displaying evidence of oxidative stress suggests that the major mechanism of action is attenuation of free radical damage.
- Published
- 2001
39. Phosphatidylinositol Synthase(PIS) mRNA Distribution in the Rat Central Nervous System and its Sequential Change during Postnatal Development Determined by Quantitative RT-PCR
- Author
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Hideaki Imai
- Subjects
Messenger RNA ,Real-time polymerase chain reaction ,medicine.anatomical_structure ,Central nervous system ,Phosphatidylinositol synthase ,medicine ,Distribution (pharmacology) ,General Medicine ,In situ hybridization ,Biology ,Molecular biology - Published
- 1999
40. Olfactory Neuroblastoma with Nasal and Suprasellar Extension: A Case Report
- Author
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Masaru Tamura, Hideaki Imai, Hideaki Kohga, Akira Zama, and Yoichi Nakazato
- Subjects
Nasal cavity ,Visual acuity ,medicine.diagnostic_test ,Olfactory Neuroblastoma ,business.industry ,Neural crest ,Magnetic resonance imaging ,General Medicine ,Anatomy ,Olfactory neuroepithelium ,medicine.anatomical_structure ,otorhinolaryngologic diseases ,Medicine ,Suprasellar extension ,medicine.symptom ,business ,Sinus (anatomy) - Abstract
We report the case of a patient with an olfactory neuroblastoma which occupied the sphenoid sinus with nasal and suprasellar extension. Presenting symptoms included diminished visual acuity in the right eye. Computed tomography (CT) and magnetic resonance (MR) imaging demonstrated a tumor that had destroyed most of the sphenoid sinus, extending to the nasal cavity and suprasellar region. The patient underwent surgery via a fronto-temporal approach. An extensive review of the literature revealed approximately 300 cases of olfactory neuroblastoma, however, only two of these cases involved the sphenoidal region. This tumor is not thought to be derived from the olfactory neuroepithelium, but rather from neural crest tissue surrounding the sphenoid sinus.
- Published
- 1998
41. Ptosis as partial oculomotor nerve palsy due to compression by infundibular dilatation of posterior communicating artery, visualized with three-dimensional computer graphics: case report
- Author
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Megumi Takasago, Nobuhito Saito, Hirofumi Nakatomi, Kuniaki Saito, Masanori Yoshino, Yuta Fukushima, Hideaki Imai, and Taichi Kin
- Subjects
Progressive ptosis ,Communicating Artery ,Microsurgery ,Case Report ,Imaging, Three-Dimensional ,Ptosis ,medicine.artery ,medicine ,Oculomotor Nerve Diseases ,ptosis ,Blepharoptosis ,Humans ,Computer Simulation ,Posterior communicating artery ,Oculomotor nerve palsy ,posterior communicating artery ,medicine.diagnostic_test ,business.industry ,Oculomotor nerve ,Nerve Compression Syndromes ,Angiography, Digital Subtraction ,Intracranial Aneurysm ,Anatomy ,Middle Aged ,medicine.disease ,Image Enhancement ,Surgical Instruments ,Nerve compression syndrome ,Cerebral Angiography ,Pituitary Gland ,computer graphics ,oculomotor nerve palsy ,Surgery ,Female ,infundibular dilatation ,Neurology (clinical) ,medicine.symptom ,business ,Magnetic Resonance Angiography ,Cerebral angiography ,Dilatation, Pathologic - Abstract
Oculomotor nerve palsy (ONP) due to internal carotid-posterior communicating artery (PcomA) aneurysm generally manifests as partial nerve palsy including pupillary dysfunction. In contrast, infundibular dilatation (ID) of the PcomA has no pathogenic significance, and mechanical compression of the cranial nerve is extremely rare. We describe a 60-year-old woman who presented with progressive ptosis due to mechanical compression of the oculomotor nerve by an ID of the PcomA. Three-dimensional computer graphics (3DCG) accurately visualized the mechanical compression by the ID, and her ptosis was improved after clipping of the ID. ID of the PcomA may cause ONP by mechanical compression and is treatable surgically. 3DCG are effective for the diagnosis and preoperative simulation.
- Published
- 2013
42. Novel modified method for injection into the cerebrospinal fluid via the cerebellomedullary cistern in mice
- Author
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Yili, Chen, Hideaki, Imai, Akihiro, Ito, and Nobuhito, Saito
- Subjects
Male ,Methylene Blue ,Mice, Inbred C57BL ,Mice ,Time Factors ,Dose-Response Relationship, Drug ,Endothelin-1 ,Microinjections ,Cerebrovascular Circulation ,Cisterna Magna ,Animals ,Brain - Abstract
A modified method of injection into the cerebellomedullary (CM) cistern of mice was developed based on fixation of the mouse with a special mask under inhalation anesthesia, and exposure of the sagittal suture of the cranium and midline of the nape to allow us to visualize injection point directly. The accuracy of the modified method was evaluated using the temporal and spatial intracranial distribution of dye by intracisternal injection of 6- microliter methylene blue aqueous solution. A high concentration of dye was found in the CM cistern, the ventral cisterns, and intracranial proximal portion of the main cranial nerves at 1 hour after injection. The color of the dye in the CM cistern and the ventral cisterns was lighter, and the dye had reached the intracranial distal portion of the main cranial nerves at 6 hours after injection. The dye was completely eliminated by cerebrospinal fluid (CSF) circulation at 24 hours after injection. No severe brain injury was found in any of the 20 mice. Intracisternal injection was successful in all 14 mice sacrificed 1 hour or 6 hours after injection according to the confirmation of dye distribution. The effects of central administration of endothelin-1 (ET1) were evaluated on cerebral blood supply, constriction of cerebral arteries, and change of respiration in mice. Three doses of ET1 were studied: 2 micrograms (0.8 nmol), 4 micrograms (1.6 nmol), and 6 micrograms (2.4 nmol). Cerebral blood flow (CBF) was monitored for 60 minutes following injection using a laser Doppler probe. Intracisternal ET1 injection induced dose-dependent reduction of CBF, constriction of cerebral arteries, and respiratory depression in mice. This modified method of injection into the CM cistern under direct visualization provides accurate and reproducible injection into the CSF, and can be used to investigate the effects of various chemical substances on the central nervous system in mice.
- Published
- 2013
43. Molecular cloning of rat phosphatidylinositol synthase cDNA by functional complementation of the yeastSaccharomyces cerevisiae pismutation
- Author
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Kohei Hosaka, Jun-ichi Nikawa, Susumu Tanaka, Satoshi Yamashita, and Hideaki Imai
- Subjects
DNA, Complementary ,Molecular Sequence Data ,Saccharomyces cerevisiae ,Biophysics ,Transferases (Other Substituted Phosphate Groups) ,Rat brain ,Molecular cloning ,Biochemistry ,chemistry.chemical_compound ,Structural Biology ,Complementary DNA ,Phosphatidylinositol synthesis ,Genetics ,Animals ,Tissue Distribution ,Inositol ,Amino Acid Sequence ,RNA, Messenger ,Phosphatidylinositol ,Cloning, Molecular ,Molecular Biology ,Base Sequence ,biology ,Molecular mass ,Genetic Complementation Test ,Brain ,Membrane Proteins ,Cell Biology ,Functional cloning ,CDP-Diacylglycerol-Inositol 3-Phosphatidyltransferase ,biology.organism_classification ,Molecular biology ,Yeast ,Rats ,carbohydrates (lipids) ,Complementation ,chemistry ,Mutation ,lipids (amino acids, peptides, and proteins) - Abstract
Phosphatidylinositol synthase (CDP-1,2-diacyl-sn-glycerol: 3-phosphatidyltransferase, EC 2.7.8.11) catalyzes the formation of phosphatidylinositol and CMP from CDP-diacyl-glycerol and myo-inositol. We have cloned a phosphatidylinositol synthase cDNA from rat brain by functional complementation of the yeast pis mutation, which is defective in phosphatidylinositol synthase. The deduced protein comprised 213 amino acids with a calculated molecular mass of 23 613 Da. The predicted protein sequence is highly homologous to the previously determined yeast phosphatidylinositol synthase sequence. The cDNA hybridized to a 1.7-kb mRNA that was abundantly expressed in rat brain and kidney.
- Published
- 1996
44. Diagnosis and Treatment of Brainstem Abscess Using Magnetic Resonance Imaging and Microsurgical Aspiration
- Author
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Akira Zama, Nobuo Ono, Hideaki Imai, and Masaru Tamura
- Subjects
medicine.medical_specialty ,Respiratory distress ,medicine.diagnostic_test ,business.industry ,medicine.medical_treatment ,Magnetic resonance imaging ,Microsurgery ,medicine.disease ,Lesion ,Brainstem glioma ,medicine ,Surgery ,Neurology (clinical) ,Radiology ,Brainstem ,medicine.symptom ,business ,Abscess ,Brain abscess - Abstract
A 6-year-old boy presented with a pontine abscess initially misdiagnosed as brainstem glioma, but he deteriorated rapidly and developed new symptoms of respiratory distress. Magnetic resonance (MR) imaging revealed a rapidly growing mass lesion in the pons. Microsurgical evacuation of the abscess via a suboccipital retromastoid approach resulted in neurological improvement and resolution of the lesion on MR images. Brainstem abscess can be successfully treated with early, accurate diagnosis based on MR imaging and appropriate microsurgical and antibiotic management.
- Published
- 1995
45. Subcortically and callosally projecting neurons are distinct neuronal pools in the motor cortex of the reeler mouse
- Author
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Hideaki, Imai, Tatsuro, Yamamoto, Yu, Katsuyama, Satoshi, Kikkawa, and Toshio, Terashima
- Subjects
Male ,Neurons ,Mice ,Mice, Neurologic Mutants ,Reelin Protein ,Spinal Cord ,Thalamus ,Amidines ,Motor Cortex ,Animals ,Female ,Fluorescent Dyes ,Injections - Abstract
Subcortically projecting neurons and callosally projecting ones are distinct neuronal pools in the cerebral cortex of the rodents. However, cortical efferent neurons are known to project multiple targets transiently by plural collateral axons. These plural axons are eliminated during prenatal and postnatal development. In the cerebral cortex of the Reelin-deficient mouse, reeler, which is caused by mutation of the reelin gene, cortical efferent neurons are ectopically distributed. However, it is still unknown whether cortical efferent neurons in the reeler mouse lose surplus collateral axons or maintain them during developmental periods. If surplus collaterals of malpositioned cortical neurons are not eliminated, neurons projecting subcortically may project their axons to the contralateral hemisphere. To test this plausible hypothesis, we made double injections of two fluorescent dyes, Fast Blue and Diamidino yellow dihydrochloride into two of three regions, i.e., upper cervical cord, ventral lateral thalamic nucleus, and contralateral motor cortex of the normal and reeler mice, to label corticospinal, corticothalamic and callosal commissure neurons in the motor cortex, retrogradely. No double labeled neurons were identified in the motor cortex of the normal and reeler mice, although the distribution patterns of these cortical efferent neurons were completely different between normal and reeler mice. These findings strongly suggest that collateral elimination of cortical efferent neurons during developing periods are not affected in this mutant mouse.
- Published
- 2012
46. Dorsal Forebrain-Specific Deficiency of Reelin-Dab1 Signal Causes Behavioral Abnormalities Related to Psychiatric Disorders.
- Author
-
Hideaki Imai, Hirotaka Shoji, Masaki Ogata, Yoshiteru Kagawa, Yuji Owada, Tsuyoshi Miyakawa, Kenji Sakimura, Toshio Terashima, and Yu Katsuyama
- Published
- 2017
- Full Text
- View/download PDF
47. Cyclophilin C-associated protein and cyclophilin C mRNA are upregulated in penumbral neurons and microglia after focal cerebral ischemia
- Author
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Nobutaka Kawahara, Fumiaki Honda, Tatsuya Shimizu, Mitsunobu Nakamura, Nobuhito Saito, Shinichiro Tomizawa, Hideaki Imai, and Koji Seki
- Subjects
Male ,Pathology ,medicine.medical_specialty ,Nerve Tissue Proteins ,In situ hybridization ,Brain Ischemia ,Rats, Sprague-Dawley ,Cyclophilins ,Cyclosporin a ,medicine ,Animals ,RNA, Messenger ,Cyclophilin ,In Situ Hybridization ,Glycoproteins ,Peptidylprolyl isomerase ,Neurons ,Extracellular Matrix Proteins ,biology ,Blotting, Northern ,Molecular biology ,Immunohistochemistry ,Cyclophilin C ,Rats ,Up-Regulation ,Neurology ,Cis-trans-Isomerases ,biology.protein ,Neurology (clinical) ,Microglia ,NeuN ,Cardiology and Cardiovascular Medicine ,Carrier Proteins ,Immunostaining - Abstract
Immunophilin ligands, such as cyclosporin A and FK506, have neuroprotective effects in experimental stroke models, although the precise mechanism is unclear. Cyclophilin C-associated protein (CyCAP) is a natural cellular ligand for the immunophilin, cyclophilin C, and has a protective effect against endotoxins by downmodulating the proinflammatory response. Expressions of CyCAP and cyclophilin C mRNA in a rat middle cerebral artery (MCA) occlusion ischemia model were investigated by Northern blotting and in situ hybridization. Both CyCAP and cyclophilin C mRNAs were ubiquitously distributed in the neurons of the normal brain. Expression increased in neurons of the periinfarct zone up to 7 days after MCA occlusion. The neuronal distribution was confirmed by counterimmunostaining of NeuN. Both mRNAs were predominantly expressed in microglia of the ischemic core at 7 days, confirmed by immunostaining with the microglial marker, ED1. The quantification of CyCAP and cyclophilin C mRNAs at 7 days by Northern blot analysis showed the 8.5-fold increase ( P
- Published
- 2005
48. New method for the quantitative assessment of axonal damage in focal cerebral ischemia
- Author
-
David I. Graham, Hideaki Imai, Hiroyuki Masayasu, I. Mhairi Macrae, and James McCulloch
- Subjects
Male ,Pathology ,medicine.medical_specialty ,Middle Cerebral Artery ,Ischemia ,Corpus callosum ,030218 nuclear medicine & medical imaging ,Central nervous system disease ,White matter ,Rats, Sprague-Dawley ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Reference Values ,medicine.artery ,medicine ,Amyloid precursor protein ,Animals ,Axon ,Neurons ,biology ,business.industry ,Ebselen ,medicine.disease ,Axons ,Rats ,medicine.anatomical_structure ,Neurology ,chemistry ,Ischemic Attack, Transient ,Middle cerebral artery ,biology.protein ,Neurology (clinical) ,Cardiology and Cardiovascular Medicine ,business ,030217 neurology & neurosurgery - Abstract
Quantification of damage in both grey and white matter is required for comprehensive assessment of neuroprotective drug efficacy. Although methods for quantification of neuronal perikaryal damage after ischemia are well established, assessment of axonal damage has been limited. This article describes a new method for quantitation of axonal injury after middle cerebral artery (MCA) occlusion in rats and its application to the study of the antioxidant ebselen. The methodology is based on immunohistochemical detection of amyloid precursor protein (APP) accumulation in deformed, swollen axons in zones of ischemia. Sixty-five axon-rich sites throughout the MCA territory are assessed for the presence (scored 1) or absence (scored 0) of accumulated APP in axonal swellings. Scores for individual sites are summated in predefined neuroanatomic regions (e.g. corpus callosum), stereotaxic levels, or for a total hemisphere APP score. Both intra-rater and inter-rater reproducibility were high ( r = 0.87 and 0.80, respectively). Ebselen (1 mg kg−1 hr−1, intravenously) significantly reduced the volume of neuronal perikaryal damage (24%, P < 0.01) and axonal damage (total APP score reduced from 27 [23.9 to 35.1, 95% CI] to 21.5 [18.2 to 23.3], P = 0.002 with ebselen treatment). In conclusion, a robust and generally applicable method is described for assessing pathologic features in myelinated fiber tracts that is sensitive for detection of drug effects on axonal damage.
- Published
- 2002
49. Wall-to-lumen ratio of intracranial arteries measured by indocyanine green angiography.
- Author
-
Daichi Nakagawa, Masaaki Shojima, Masanori Yoshino, Taichi Kin, Hideaki Imai, Seiji Nomura, Toki Saito, Hirofumi Nakatomi, Hiroshi Oyama, and Nobuhito Saito
- Subjects
INDOCYANINE green ,ANGIOGRAPHY ,VASCULAR medicine ,MICROSURGERY ,NEAR infrared radiation ,AUTOPSY ,IN vivo studies - Abstract
Background: The wall-to-lumen ratio (WLR) is an important parameter in vascular medicine because it indicates the character of vascular wall as well as the degree of stenosis. Despite the advances in medical imaging technologies, it is still difficult to measure the thin-walled normal intracranial arteries, and the reports on the WLR of normal intracranial artery are limited. It might be possible to calculate the WLR using the indocyanine green (ICG) angiography, which is used to observe intracranial vessels during microsurgery. Purpose: To evaluate the WLR of normal intracranial arteries using ICG angiography. Materials and Methods: From the three cases in which ICG angiography was recorded with a ruler during microsurgery, 20 measurement points were chosen for the analysis. The ICG was injected intravenously with a dose of 0.2 mg/kg, and the vessels were inspected at high magnification using an operating microscope equipped with near-infrared illumination system. The vessel outer diameter and the luminal diameter were measured using the images before and after the ICG arrival based on the pixel ratio method using a ruler as reference, respectively. The WLR was calculated as 0.5 × (vessel outer diameter - vessel luminal diameter). Results: The WLR (mean ± standard deviation) of normal intracranial arteries was 0.086 ± 0.022. The WLR tended to be high in small arteries. Conclusion: The WLR of normal intracranial arteries calculated using ICG angiography was consistent with the WLR reported in the previous reports based on human autopsy. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
50. Nonlinear spectrum estimation using a new neural network with a level estimator
- Author
-
Yoshikazu Miyanaga, Hideaki Imai, and Koji Tochinai
- Subjects
Signal processing ,Theoretical computer science ,Acoustics and Ultrasonics ,Artificial neural network ,Computer science ,Node (networking) ,Supervised learning ,Estimator ,Perceptron ,Nonlinear system ,Arts and Humanities (miscellaneous) ,Multilayer perceptron ,Cluster analysis ,Algorithm - Abstract
This paper proposes a new nonlinear signal processing by using a three‐layered network which is trained with self‐organized clustering and supervised learning. The network consists of three layers, i.e., a self‐organized layer, an evaluation layer, and an output layer. Since the evaluation layer is designed as a simple perceptron network and the output layer is designed as the fixed weight linear nodes, the training complexity is the same as the self‐organized clustering and a simple perceptron network. In other words, quite high speed training can be realized. Generally speaking, since the data range usually used in signal processing is arbitrarily large, the network output should also cover this range. However, it may be difficult for only one node in the network to output these data. Instead of this technique, if this dynamic range is covered by using several nodes, the complexity of each node is reduced and the associated range is also quite limited. This results in a higher performance of this network than the conventional ones. As one of the objectives, this paper introduces the spectrum envelope estimation of speech waveforms. It is shown that accurate spectrum envelopes can be obtained.
- Published
- 1996
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