Yasuhisa Kanematsu, Yuki Kanazawa, Kenji Shimada, Masaaki Korai, Takeshi Miyamoto, Shu Sogabe, Manabu Ishihara, Izumi Yamaguchi, Takeshi Oya, Nobuaki Yamamoto, Yuki Yamamoto, Miyoshi Mitsuharu, Masafumi Harada and Yasushi Takagi : Characterization of carotid plaques using chemical exchange saturation transfer imaging, Neuroradiology, Vol.66, No.9, 1617-1624, 2024.
(要約)
The preoperative assessment of carotid plaques is necessary to render revascularization safe and effective. The aim of this study is to evaluate the usefulness of chemical exchange saturation transfer (CEST)-MRI, particularly amide proton transfer (APT) imaging as a preoperative carotid plaque diagnostic tool. We recorded the APT signal intensity on concentration maps of 34 patients scheduled for carotid endarterectomy. Plaques were categorized into group A (APT signal intensity ≥ 1.90 E-04; n = 12) and group B (APT signal intensity < 1.90 E-04; n = 22). Excised plaques were subjected to histopathological assessment and, using the classification promulgated by the American Heart Association, they were classified as intraplaque hemorrhage-positive [type VI-positive (tVI)] and -negative [no intraplaque hemorrhage (tVI)]. Of the 34 patients, 22 (64.7%) harbored tVI- and 12 (35.3%) had tVI plaques. The median APT signals were significantly higher in tVI- than tIVI patients (2.43 E-04 (IQR = 0.98-4.00 E-04) vs 0.54 E-04 (IQR = 0.14-1.09 E-04), p < .001). Histopathologically, the number of patients with tVI plaques was significantly greater in group A (100%, n = 12) than group B (45%, n = 22) (p < .01). The number of symptomatic patients or asymptomatic patients with worsening stenosis was also significantly greater in group A than group B (75% vs 36%, p < .01). In unstable plaques with intraplaque hemorrhage and in patients with symptoms or progressive stenosis, the ATP signals were significantly elevated. CEST-MRI studies has the potential for the preoperative assessment of the plaques' characteristics.
Hiroshi Kagusa, Yamaguchi Izumi, Shono Kenji, Mizobuchi Yoshifumi, Shikata Eiji, Taku Matsuda, Takeshi Miyamoto, Keijiro Hara, Kitazato T Keiko, Yoshihiro Uto, Kanematsu Yasuhisa and Yasushi Takagi : Differences in amyloid-β and tau/p-tau deposition in blood-injected mouse brains using micro-syringe to mimic traumatic brain microhemorrhages, Journal of Chemical Neuroanatomy, Vol.130, 102258, 2023.
(要約)
Cerebral microbleeds (CMBs) due to traumatic brain injuries (TBI) have been shown to lead to cognitive decline and impairment. CMBs caused by TBI may be associated with pathophysiological mechanisms involving inflammation and the accumulation of amyloid-β (Aβ), tau, and phosphorylated tau (p-tau), contributing to cognitive abnormalities. However, their relationships remain unclear. To test our hypothesis that Aβ, tau, and p-tau are accumulated and regulated separately in mice with injuries imitating CMBs from TBI, we studied. Seven-week-old C57BL/6 male mice were injected with 15 μL of heparinized autologous blood or saline by micro-syringe into the front lobe. Expression profiles and regulation of Aβ, tau, and p-tau were assessed immunohistochemically over time. On day 7 after blood injection, Iba-1 and S100B cells in damaged cortex adjacent to the injection site were higher than saline injection group and non-injected sham. On days 3-14, Aβ deposition were gradually increased but normalized by day 28. In contrast, tau/p-tau deposition gradually increased during days 14-28 and dispersed along the corticomedullary junction adjacent to hem deposits, indicating different expression profiles from Aβ. Deposits of Aβ, but not tau/p-tau, were phagocytosed by CD163 macrophages increased by Gc-protein macrophage-activating factor during days 7-28, suggesting different mechanisms of deposition and regulation between Aβ and tau/p-tau. Deposition and regulation differ between Aβ and tau/p-tau in mice with injuries mimicking CMBs from TBI. Further clarification of relationships between the pathologies of cognitive impairment and their neurodegenerative consequences is needed.
Manabu Ishihara, Yasuhisa Kanematsu, Nobuaki Yamamoto, Kenji Shimada, Takeshi Miyamoto, Izumi Yamaguchi, Shu Sogabe, Yuki Yamamoto, Jun Oto and Yasushi Takagi : Prognostic factors for acute large vessel occlusion with NIHSS 5 or lower., The Journal of Medical Investigation : JMI, Vol.70, No.1.2, 22-27, 2023.
(要約)
MCA occlusion is associated with poor prognosis, even with NIHSS score ??5, and d-IAS may provide a predictor. J. Med. Invest. 70 : 22-27, February, 2023.
Cerebrovascular and cardiovascular disease are the main causes of death in Japan. The leading causes of the need for long-term care in Japan are also cerebrovascular and cardiovascular disease, which together account for more than one-fourth of the total. The Cerebrovascular and Cardiovascular Disease Control Act, of Japanese national law, was promulgated by a legislative act in 2018. On the basis of the Cerebrovascular and Cardiovascular Disease Control Act, the Ministry of Health, Labour and Welfare, Japan, published the Japanese National Plan for Promotion of Measures Against Cerebrovascular and Cardiovascular Disease (Japanese National Plan) in 2020. By the example of the Japanese National Plan, Tokushima prefecture established a cerebrovascular and cardiovascular disease countermeasure promotion plan to progress cerebrovascular and cardiovascular disease measures according to their own circumstances. One of the important measures of the plan is improving emergency transportation systems. Patients with intracranial large vessel occlusion strokes should be served by direct transfer to endovascular capable centers avoiding delays by misguided transfer to primary stroke centers. Considering the limited availability of endovascular capable centers, accurate identification of patients with high probability of having large vessel occlusion strokes in the prehospital setting is importance. To address this problem, we introduced prehospital scale called Field Assessment Stroke Triage for Emergency Destination (FAST-ED) on emergency transportation systems in Tokushima city.
(キーワード)
Cerebrovascular and cardiovascular disease / emergency transportation systems / prehospital scale
Yoshitaka Kurashiki, Hiroshi Kagusa, Kenji Yagi, Tomoya Kinouchi, Manabu Sumiyoshi, Takeshi Miyamoto, Kenji Shimada, Keiko T Kitazato, Yoshihiro Uto and Yasushi Takagi : Role of post-ischemic phase-dependent modulation of anti-inflammatory M2-type macrophages against rat brain damage, Journal of Cerebral Blood Flow and Metabolism, 2022.
(要約)
Cerebral ischemia triggers inflammatory changes, and early complications and unfavorable outcomes of endovascular thrombectomy for brain occlusion promote the recruitment of various cell types to the ischemic area. Although anti-inflammatory M2-type macrophages are thought to exert protective effects against cerebral ischemia, little has been clarified regarding the significance of post-ischemic phase-dependent modulation of M2-type macrophages. To test our hypothesis that post-ischemic phase-dependent modulation of macrophages represents a potential therapy against ischemic brain damage, the effects on rats of an M2-type macrophage-specific activator, Gc-protein macrophage-activating factor (GcMAF), were compared with vehicle-treated control rats in the acute (day 0-6) or subacute (day 7-13) phase after ischemia induction. Acute-phase GcMAF treatment augmented both anti-inflammatory CD163 M2-type- and pro-inflammatory CD16 M1-type macrophages, resulting in no beneficial effects. Conversely, subacute-phase GcMAF injection increased only CD163 M2-type macrophages accompanied by elevated mRNA levels of arginase-1 and interleukin-4. M2-type macrophages co-localized with CD36 phagocytic cells led to clearance of the infarct area, which were abrogated by clodronate-liposomes. Expression of survival-related molecules on day 28 at the infarct border was augmented by GcMAF. These data provide new and important insights into the significance of M2-type macrophage-specific activation as post-ischemic phase-dependent therapy.
Eiji Shikata, Takeshi Miyamoto, Tadashi Yamaguchi, Izumi Yamaguchi, Hiroshi Kagusa, Daiki Gotoh, Kenji Shimada, Yoshiteru Tada, Kenji Yagi, 北里 慶子, Yasuhisa Kanematsu and Yasushi Takagi : An imbalance between RAGE/MR/HMGB1 and ATP1α3 is associated with infammatory changes in rat brain harboring cerebral aneurysms prone to rupture, Journal of Neuroinflammation, Vol.19, No.161, 161, 2022.
(要約)
An aneurysmal subarachnoid hemorrhage is a devastating event. To establish an effective therapeutic strategy, its pathogenesis must be clarified, particularly the pathophysiology of brain harboring intracranial aneurysms (IAs). To elucidate the pathology in brain harboring IAs, we examined the significance of the receptor for advanced glycation end-products (RAGE)/mineralocorticoid receptor (MR) pathway and Na/K-ATPase (ATP1α3). Ten-week-old female rats were subjected to oophorectomy as well as hypertension and hemodynamic changes to induce IAs, and were fed a high-salt diet. Brain damage in these rats was assessed by inflammatory changes in comparison to sham-operated rats fed a standard diet. Six weeks after IA induction (n = 30), irregular morphological changes, i.e., an enlarged vessel diameter and vascular wall, were observed in all of the left posterior cerebral arteries (Lt PCAs) prone to rupture. Approximately 20% of rats had ruptured IAs within 6 weeks. In brain harboring unruptured IAs at the PCA, the mRNA levels of RAGE and MR were higher, and that of ATP1α3 was lower than those in the sham-operated rats (p < 0.05, each). Immunohistochemically, elevated expression of RAGE and MR, and decreased expression of ATP1α3 were observed in the brain parenchyma adjacent to the Lt PCA, resulting in increased Iba-1 and S100B expression that reflected the inflammatory changes. There was no difference between the unruptured and ruptured aneurysm rat groups. Treatment with the MR antagonist esaxerenone abrogated these changes, and led to cerebral and vascular normalization and prolonged subarachnoid hemorrhage-free survival (p < 0.05). Regulation of the imbalance between the RAGE/MR pathway and ATP1α3 may help attenuate the damage in brain harboring IAs, and further studies are warranted to clarify the significance of the down-regulation of the MR/RAGE pathway and the up-regulation of ATP1α3 for attenuating the pathological changes in brain harboring IAs.
Kenji Shimada, Izumi Yamaguchi, Takeshi Miyamoto, Shu Sogabe, Kazuhisa Miyake, Yasuhisa Kanematsu and Yasushi Takagi : Efficacy of intraarterial indocyanine green videoangiography in surgery for arteriovenous fistula at the craniocervical junction in a hybrid operating room: illustrative cases, Journal of Neurosurgery. Case Lessons, Vol.3, No.23, 1-6, 2022.
(要約)
Sufficient understanding of the angioarchitecture of an arteriovenous fistula (AVF) at the craniocervical junction (CCJ) is crucial to surgical treatment but is often difficult because of the complex vascular anatomy. Intraarterial indocyanine green (ICG) videoangiography has emerged as a more useful option for understanding the vascular anatomy than intravenous ICG videoangiography. This report describes two cases of CCJ AVFs successfully treated by surgery using intraarterial ICG videoangiography and describes the efficacy of this technique. Case 1 involved a 71-year-old man presenting with tetraparesis after sudden onset of severe headache due to subarachnoid hemorrhage (SAH). Digital subtraction angiography (DSA) demonstrated CCJ epidural AVF. Intraarterial ICG videoangiography revealed the drainer, which had been difficult to identify. The AVF disappeared after disconnection of the drainer. Case 2 involved a 68-year-old man presenting with severe headache due to SAH. DSA showed multiple AVFs at the CCJ and cerebellar tentorium. Intraarterial ICG videoangiography demonstrated concomitant perimedullary AVF and dural AVF at the CCJ. All AVFs disappeared postoperatively. Intraarterial ICG videoangiography was useful for definitive diagnosis of CCJ AVF, facilitating identification of feeders and drainers with bright and high phase contrast and allowing repeated testing to confirm flow direction.
Izumi Yamaguchi, Yasuhisa Kanematsu, Kenji Shimada, Nobuaki Yamamoto, Kazuhisa Miyake, Takeshi Miyamoto, Shu Sogabe, Eiji Shikata, Manabu Ishihara, 山本 陽子, Kazutaka Kuroda and Yasushi Takagi : Single-session hematoma removal and transcortical venous approach for coil embolization of an isolated transverse-sigmoid sinus dural arteriovenous fistula in a hybrid operating room: illustrative case, Journal of Neurosurgery. Case Lessons, Vol.3, No.21, CASE2267, 2022.
(要約)
Dural arteriovenous fistula (DAVF) can present with massive hematoma, which sometimes requires emergent removal. Therefore, a surgical strategy for single-session hematoma removal and shunt occlusion in the same surgical field is important. A 73-year-old man was transferred to the authors' hospital with a headache. Brain computed tomography (CT) revealed an intracerebral hematoma in the right temporoparietal lobe (hematoma volume 12 ml). A cerebral angiogram revealed a right isolated transverse-sigmoid sinus (TSS)-DAVF fed by the occipital artery and middle meningeal artery. There was cortical venous reflux into the Labbé vein and posterior parietal vein. Percutaneous transarterial and transvenous embolization were unsuccessful. The following day, his consciousness level acutely declined with a headache, and brain CT showed hematoma expansion (hematoma volume 41 ml) with a midline shift. Therefore, the authors performed single-session hematoma removal and a transcortical venous approach for coil embolization of an isolated TSS-DAVF in a hybrid operating room. His postoperative course was uneventful. No recurrence was observed 3 months postoperatively on cerebral angiography. Single-session hematoma removal and a transcortical venous approach for coil embolization of an isolated TSS-DAVF is considered in cases with massive hematoma. This strategy is useful, considering recent developments in hybrid operating rooms.
Tadashi Yamaguchi, Takeshi Miyamoto, Eiji Shikata, Izumi Yamaguchi, Kenji Shimada, Kenji Yagi, Yoshiteru Tada, Masaaki Korai, Keiko T. Kitazato, Yasuhisa Kanematsu and Yasushi Takagi : Activation of the NLRP3/IL-1β/MMP-9 pathway and intracranial aneurysm rupture associated with the depletion of ERα and Sirt1 in oophorectomized rats, Journal of Neurosurgery, 1-8, 2022.
(要約)
Subarachnoid hemorrhage (SAH) due to intracranial aneurysm (IA) rupture is often a devastating event. Since the incidence of SAH increases especially in menopause, it is crucial to clarify the detailed pathogenesis of these events. The activation of vascular nucleotide-binding oligomerization domain-like receptor family pyrin domain-containing 3 (NLRP3) inflammasomes has been studied in ischemic stroke and cardiovascular disease. However, the role of NLRP3 in IA rupture still needs to be explained. The authors sought to test their hypothesis that, under estrogen-deficient conditions, activation of NLRP3 inflammasomes via downregulation of the estrogen receptor (ER) facilitates IA rupture. Ten-week-old female Sprague Dawley rats with and without oophorectomy were subjected to hemodynamic changes and hypertension (OVX+/HT and OVX-/HT, respectively) and fed a high-salt diet. Separately, using human brain endothelial cells (HBECs) and human brain smooth muscle cells (HBSMCs), the authors tested the effect of NLRP3 under estrogen-free conditions and in the presence of estradiol or of ER agonists. In OVX+/HT rats, the frequency of IA rupture was significantly higher than in OVX-/HT rats (p = 0.03). In the left posterior cerebral artery prone to rupture in OVX+/HT rats, the levels of the mRNAs encoding ERα and Sirt1, but not of that encoding ERβ, were decreased, and the levels of the mRNAs encoding NLRP3, interleukin-1β (IL-1β), and matrix metalloproteinase 9 (MMP-9) were elevated. Immunohistochemical analysis demonstrated that the expression profiles of these proteins correlated with their mRNA levels. Treatment with an ER modulator, bazedoxifene, normalized the expression profiles of these proteins and improved SAH-free survival. In HBECs and HBSMCs under estrogen-free conditions, the depletion of ERα and Sirt1 and the accumulation of NLRP3 were counteracted by exposure to estradiol or to an ERα agonist but not to an ERβ agonist. To the authors' knowledge, this work represents the first demonstration that, in an aneurysm model under estrogen-deficient conditions, the depletion of ERα and Sirt1 may contribute to activation of the NLRP3/IL-1β/MMP-9 pathway, facilitating the rupture of IAs in the estrogen-deficient rat IA rupture model.
Yuki Yamamoto, Nobuaki Yamamoto, Yasuhisa Kanematsu, Izumi Yamaguchi, Manabu Ishihara, Takeshi Miyamoto, Shu Sogabe, Kenji Shimada, Yasushi Takagi and Yuishin Izumi : The claw sign predicts first-pass effect in mechanical thrombectomy for cerebral large vessel occlusion in the anterior circulation, Surgical Neurology International, Vol.13, No.72, 1-7, 2022.
(要約)
Mechanical thrombectomy (MT) is an effective treatment for acute cerebral large vessel occlusion (LVO). Complete recanalization of vessels in a single procedure is defined as the first-pass effect (FPE) and is associated with good prognosis. In this study, angiographic clot protruding sign termed the "claw sign," was examined as candidate preoperative imaging factor for predicting the FPE. We retrospectively analyzed data from 91 consecutive patients treated for acute LVO in the anterior circulation by MT between January 2014 and December 2019. The claw sign was defined as a thrombus that protruded proximally by more than half of the diameter of the parent artery. Radiological findings such as claw sign, clinical and etiological features, and outcomes were compared between groups with and without successful FPE. Multivariate analysis was conducted to evaluate perioperative factors associated with FPE. FPE was achieved in 26 of 91 (28.6%) patients and the claw sign was observed in 34 of 91 (37.4%) patients. The claw sign was significantly more frequent in the successful FPE group than in the failed FPE group (53.8% vs. 30.8%; = 0.040). After the multivariate analysis, the claw sign was the only pretreatment parameter that could predict FPE (odds ratio, 2.67; 95% confidence interval, 1.01-7.06; = 0.047). The claw sign is an angiographic imaging factor that might predict FPE after MT for anterior circulation acute ischemic stroke.
Kenji Shimada, Izumi Yamaguchi, Manabu Ishihara, Takeshi Miyamoto, Shu Sogabe, Kazuhisa Miyake, Yoshiteru Tada, 北里 慶子, Yasuhisa Kanematsu and Yasushi Takagi : Involvement of Neutrophil Extracellular Traps in Cerebral Arteriovenous Malformations, World Neurosurgery, E1-E7, 2021.
(要約)
Cerebral arteriovenous malformations (cAVMs) represent tangles of abnormal vasculature without intervening capillaries. High-pressure vascular channels due to abnormal arterial and venous shunts can lead to rupture. Multiple pathways are involved in the pathobiology of cAVMs including inflammation and genetic factors such as KRAS mutations. Neutrophil release of nuclear chromatin, known as neutrophil extracellular traps (NETs), plays a multifunctional role in infection, inflammation, thrombosis, intracranial aneurysms, and tumor progression. However, the relationship between NETs and the pathobiology of cAVMs remains unknown. We tested whether NETs play a role in the pathobiology of cAVMs. We analyzed samples from patients who had undergone surgery for cAVM and immunohistochemically investigated expression of citrullinated histone H3 (CitH3) as a marker of NETs. CitH3 expression was compared among samples from cAVM patients, epilepsy patients, and normal human brain tissue. Expressions of thrombotic and inflammatory markers were also examined immunohistochemically in samples from cAVM patients. Expression of CitH3 derived from neutrophils was observed intravascularly in all cAVM samples but not other samples. Nidi of AVMs showed migration of many Iba-I-positive cells adjacent to the endothelium and endothelial COX2 expression, accompanied by expression of IL-6 and IL-8 in the endothelium and intravascular neutrophils. Unexpectedly, expression of CitH3 was not necessarily localized to the vascular wall and thrombus. Our results offer the first evidence of intravascular expression of NETs, which might be associated with vascular inflammation in cAVMs.
Masaaki Korai, Yasuhisa Kanematsu, Izumi Yamaguchi, Tadashi Yamaguchi, Yuki Yamamoto, Nobuaki Yamamoto, Takeshi Miyamoto, Kenji Shimada, Junichiro Satomi, Mami Hanaoka, Kazuhito Matsuzaki, Koichi Satoh and Yasushi Takagi : Subarachnoid Hemorrhage Due to Rupture of Vertebral Artery Dissecting Aneurysms: Treatments, Outcomes, and Prognostic Factors, World Neurosurgery, Vol.152, e86-e93, 2021.
(要約)
Mortality rate after subarachnoid hemorrhage due to rupture of vertebral artery dissecting aneurysms (VADAs) is high; endovascular coil trapping is the first-line therapy to prevent rerupture. To select optimal treatments, the positional relationship between the VADA and posterior inferior cerebellar artery (PICA) and the morphology of the contralateral vertebral artery must be considered, and outcome predictors of different treatment methods and their possible complications must be identified. We retrospectively studied 44 patients with ruptured VADAs who had undergone endovascular or surgical treatment. VADA morphology was assessed on conventional preoperative angiograms, and VADAs were categorized based on their site in relation to the PICA. VADA site, treatment method, and complications were used to identify prognostic factors. The sites of the 44 VADAs were PICA-proximal (n = 3), PICA-distal (n = 22), PICA-absent (n = 7), and PICA-involved (n = 12). Treatments included internal coil trapping (n = 30), proximal coil occlusion (n = 5), and stent placement (n = 3); surgical flow alteration via an occipital artery-PICA bypass and ligation at the proximal vertebral artery and the PICA origin was performed in 6 patients. Periprocedural rebleeding was associated with a poor outcome. Internal coil trapping prevented the rerupture of PICA-proximal and PICA-absent VADAs, and flow alteration prevented rerupture of PICA-involved VADAs; there were no complications directly attributable to these procedures. Periprocedural rebleeding was a poor prognostic factor. Internal trapping of PICA-proximal and PICA-absent VADAs and flow alteration in PICA-involved VADAs prevented rerupture.
Yasuhisa Kanematsu, Kenji Shimada, Yoshiteru Tada, Masaaki Korai, Takeshi Miyamoto, Shu Sogabe, Izumi Yamaguchi, Yoko Ymamoto, Nobuaki Yamamoto, Yuki Yamamoto, Koichi Satoh and Yasushi Takagi : Coil embolization with overlapping horizontal low-profile stents to treat a giant thrombosed fetal posterior cerebral aneurysm using contralateral approach through anterior communicating artery: Case report., Surgical Neurology International, Vol.12, No.347, 2021.
(要約)
The treatment of internal carotid artery (ICA) - posterior communicating artery aneurysms (ICPC aneurysms) is challenging when a fetal posterior cerebral artery (PCA) arises from the saccular neck. This complex angioarchitecture renders endovascular approaches difficult. Giant thrombosed IC-PC aneurysms are also hard to treat by endovascular coiling because its flow-diversion effect is insufficient. We report the first case of a ruptured giant thrombosed IC-PC aneurysm associated with a fetal PCA that was successfully treated by coil embolization with retrograde overlap horizontal stenting using low-profile stents introduced through the contralateral ICA. The aneurysm was completely occluded and follow-up MRI scans demonstrated the reduction of the aneurysmal size. Our technique is advantageous because low-profile stents can be used to treat lesions not accessible with flow-diverter stents due their presence in complex angioarchitectures, and overlap stenting may have flow-diversion effects that can result in the complete occlusion of giant thrombosed aneurysms.
Kenji Shimada, Yoko Yamamoto, Takeshi Miyamoto, Shu Sogabe, Toshitaka Fujihara, Kohhei Nakajima, Yoshifumi Mizobuchi, Yasuhisa Kanematsu and Yasushi Takagi : Efficacy of Intra-arterial Indocyanine Green Videoangiography in Hemangioblastoma Surgery: A Case Report., NMC Case Report Journal, Vol.8, No.1, 295-300, 2021.
(要約)
Intravenous indocyanine green (ICG) videoangiography is reportedly useful for vascular neurosurgery, and for treating hemangioblastoma due to its high vascularity. Videoangiography obtained after intra-arterial ICG injection has emerged as a more useful option than that after intravenous injection. This report offers the first description of a case of hemangioblastoma successfully treated using intra-arterial ICG videoangiography, and describes the efficacy of this technique. A 20-year-old man presented with progressive cerebellar ataxia and dysphagia. Magnetic resonance imaging (MRI) revealed an enhanced solid tumor in the medulla oblongata. Digital subtraction angiography (DSA) showed a highly vascularized tumor. Surgery was performed to remove the tumor in a hybrid operating room. A catheter was introduced into the vertebral artery (VA) for intra-arterial ICG videoangiography. Superficial feeders and drainers were identified and flow dynamic changes in the tumor were assessed by intra-arterial ICG videoangiography. The tumor was removed after confirming lack of flow in the drainer. Intra-arterial ICG videoangiography was more useful than intravenous ICG videoangiography in hemangioblastoma surgery for identifying feeders and drainers and assessing flow dynamics in the tumor. Use of Flow 800 made these findings simpler and easier to evaluate.
Nobuaki Yamamoto, Yuki Yamamoto, Izumi Yamaguchi, Shu Sogabe, Takeshi Miyamoto, Kenji Shimada, Yasuhisa Kanematsu, Ryoma Morigaki, Yuishin Izumi and Yasushi Takagi : Percutaneous Transluminal Angioplasty and Stenting Using an Aspiration Catheter, Journal of Neuroendovascular Therapy, Vol.16, No.5, 277-282, 2021.
(要約)
<p><b>Objective</b>: During percutaneous transluminal angioplasty (PTA) for the vertebral artery, occlusion of the subclavian artery using a balloon guiding catheter may be useful to prevent embolism of clots and/or debris distal to an atherosclerotic lesion. However, when placing a balloon guiding catheter at the intended vessels is difficult, it may be useful to use an aspiration catheter (AC) for mechanical thrombectomy as an intermediate catheter to suction way clots and/or debris. We report two cases in which PTA was performed for an atherosclerotic lesion at the intracranial vertebral artery using an AC, which ended without complications.</p><p><b>Case Presentations</b>: Case 1: A 74-year-old man presented with dysarthria and was admitted to our hospital. MRI revealed severe left vertebral artery stenosis and diffuse cerebral infarct areas at the territory of the posterior circulation. The patient had an abdominal aortic aneurysm and abnormally shaped left tortuous subclavian artery. Therefore, we performed PTA and stenting via the left brachial artery. We guided a 6-Fr long sheath to the left subclavian artery, and a 6-Fr AC for thrombectomy was guided through the long sheath to the V4 portion of the left vertebral artery. Thereafter, PTA was carried out under manual aspiration from the AC. As restenosis at the atherosclerotic lesion occurred after PTA, we performed stenting using a coronary stent system for this lesion under manual aspiration from the AC. No new infarct areas were observed on post-procedural MRI. Case 2: A 74-year-old woman presented with dysarthria and was admitted to our hospital. MRI demonstrated basilar artery occlusion and diffuse cerebral infarct areas at the territory of the posterior circulation. As her symptom worsened after admission, we performed urgent mechanical thrombectomy. We first performed thrombectomy using a stent retriever and then performed PTA and stenting (PTAS) for residual basilar artery stenosis via the AC under manual aspiration.</p><p><b>Conclusion</b>: When it is difficult to place a guiding catheter at the intended vessels during PTA, an AC may be useful to prevent distal embolization.</p>
Nobuaki Yamamoto, Yuishin Izumi, Yuki Yamamoto, K Kuroda, Izumi Yamaguchi, Shu Sogabe, Takeshi Miyamoto, Kenji Shimada, Yasuhisa Kanematsu, Ryoma Morigaki and Yasushi Takagi : Factors associated with DWI-ASPECTS score in patients with acute ischemic stroke due to cerebral large vessel occlusion, Clinical Neurology and Neurosurgery, Vol.199, 106316, 2020.
(要約)
The Alberta Stroke Program Early CT score (ASPECTS) of patients with acute ischemic stroke at the time of admission varies. It is crucial to select appropriate methods of treatment, such as recombinant tissue-plasminogen activator, and/or endovascular thrombectomy. According to the recent guidelines, endovascular thrombectomy for patients with large vessel occlusion (LVO) and lesion of ischemic tissue that was not yet infarcted is effective. This result demonstrates the importance of patient selection based on neuroradiological imaging. However, there are many patients who are judged as ineligibility for recanalization therapy because of presence of large ischemic core, indicating unfavorable ASPECTS, at the time of admission. We investigated the factors associated with favorable diffusion-weighted image (DWI)-ASPECTS score at the time of admission. We studies patients with LVO within 24 h from onset who were admitted into our hospital. We divided them into two groups, with favorable DWI-ASPECTS (≥6), and unfavorable DWI-ASPECTS (<6) at the time of admission. We investigated factors associated with favorable DWI-ASPECTS by evaluation of our patients' severity of clinical symptom, etiology, and radiological findings. This study showed that mild white matter lesion (Fazekas scale ≤1), absence of internal carotid artery (ICA) occlusion and cardioembolic stroke were independent factor of favorable DWI-ASPECTS at the time of admission. (odds ratio 12.92, p < 0.001, odds ratio 0.31, p = 0.001, odds ratio 0.16, p = 0.001, respectively) CONCLUSIONS: Absence of severe white matter lesion, cardioembolic stroke, and ICA occlusion might be associated with favorable DWI-ASPECTS at the time of admission.
(キーワード)
Aged / Aged, 80 and over / Brain Ischemia / Cerebrovascular Disorders / Diffusion Magnetic Resonance Imaging / Female / Humans / Ischemic Stroke / Male / Middle Aged / Patient Admission / Prospective Studies / Retrospective Studies / Severity of Illness Index
Nobuaki Yamamoto, Yuki Yamamoto, Izumi Yamaguchi, Manabu Ishihara, Takeshi Miyamoto, Masaaki Korai, Kenji Shimada, Yasuhisa Kanematsu, Yuishin Izumi and Yasushi Takagi : Cone beam-computed tomography angiography by intravenous contrast injection is reliable to evaluate patients with large vessel occlusion, Journal of Clinical Neuroscience, Vol.70, 67-71, 2019.
(要約)
Mechanical thrombectomy (MT) for acute ischemic stroke (AIS) patients due to emergent large vessel occlusion (ELVO) is standard treatment, the benefits, however, are highly time-sensitive. After patient eligibility for reperfusion therapy is determined by conventional radiological examinations, the time to be transferred from the department of radiological examination to angiography-suites is critical. We speculated that the time required for the diagnosis of AIS might be reduced if we could determine MT eligibility in patients with ELVO at angiography-suites. Modern angiography-suites with flat panel detectors can perform cone beam (CB)-CT. We performed CB-CTA using intravenous injection of contrast agent to evaluate occlusion sites, collateral score, and construction of vessels distal to occlusion sites and determined if CB-CTA could be useful to evaluate patients with ELVO. We included 15 patients with ELVO diagnosed by conventional MRI or CT/CTA, and investigated whether CB-CTA was reliable to diagnose occlusion sites. We also studied if collateral score on CB-CTA was associated with prognosis after successful reperfusion by MT by comparison between favorable (modified Rankin scale (mRS) 0-2), and unfavorable outcome group (mRS 3-6). There was strong agreement of occlusion sites between CB-CTA and conventional radiological examination (κ = 0.80). Collateral score determined by CB-CTA was significantly different between favorable outcome and unfavorable outcome group (median collateral score 2.3 v.s. 1.3, p = 0.040). Although prospective study of AIS patients at a radiography department is indispensable, CB-CTA performed in an angiography-suite might be useful to evaluate patients with ELVO.
Izumi Yamaguchi, Yasuhisa Kanematsu, Kenji Shimada, Masaaki Korai, Takeshi Miyamoto, Eiji Shikata, Tadashi Yamaguchi, Nobuaki Yamamoto, Yuki Yamamoto, Keiko Kitazato, Yoshihiro Okayama and Yasushi Takagi : Active Cancer and Elevated D-Dimer Are Risk Factors for In-Hospital Ischemic Stroke, Cerebrovascular Diseases Extra, Vol.9, No.3, 129-138, 2019.
(要約)
Little attention has been paid to the pathogenesis of in-hospital stroke, despite poor outcomes and a longer time from stroke onset to treatment. We studied the pathophysiology and biomarkers for detecting patients who progress to in-hospital ischemic stroke (IHS). Seventy-nine patients with IHS were sequentially recruited in the period 2011-2017. Their characteristics, care, and outcomes were compared with 933 patients who had an out-of-hospital ischemic stroke (OHS) using a prospectively collected database of the Tokushima University Stroke Registry. Active cancer and coronary artery disease were more prevalent in patients with IHS than in those with OHS (53.2 and 27.8% vs. 2.0 and 10.9%, respectively; p < 0.001), the median onset-to-evaluation time was longer (300 vs. 240 min; p = 0.015), and the undetermined etiology was significantly higher (36.7 vs. 2.4%; p < 0.001). Although there was no significant difference in stroke severity at onset between the groups, patients with IHS had higher modified Rankin Scale (mRS) scores (3-6) at discharge (67.1 vs. 50.3%; p = 0.004) and rates of death during hospitalization (16.5 vs. 2.9%; p < 0.001). D-dimer (5.8 vs. 0.8 µg/mL; p < 0.001) and fibrinogen (532 vs. 430 mg/dL; p = 0.014) plasma levels at the time of onset were significantly higher in patients with IHS after propensity score matching. Multivariate logistic regression analysis revealed that active cancer (odds ratio [OR] 2.30; 95% confidence interval [CI] 1.26-4.20), prestroke mRS scores 3-5 (OR 6.78; 95% CI 3.96-11.61), female sex (OR 1.57; 95% CI 1.19-2.08), and age ≥75 years (OR 2.36; 95% CI 1.80-3.08) were associated with poor outcomes. Patients with IHS had poorer outcomes than those with OHS because of a higher prevalence of active cancer and functional dependence before stroke onset. Elevated plasma levels of D-dimer and fibrinogen, especially with active cancer, can help identify patients who are at a higher risk of progression to IHS.
Tadashi Yamaguchi, Takeshi Miyamoto, keiko Kitazato, Eiji Shikata, Izumi Yamaguchi, Masaaki Korai, Kenji Shimada, Kenji Yagi, Yoshiteru Tada, Yoshihito Matsuzaki, Yasuhisa Kanematsu and Yasushi Takagi : Time-dependent and site-dependent morphological changes in rupture-prone arteries: ovariectomized rat intracranial aneurysm model, Journal of Neurosurgery, 2019.
(要約)
The pathogenesis of intracranial aneurysm rupture remains unclear. Because it is difficult to study the time course of human aneurysms and most unruptured aneurysms are stable, animal models are used to investigate the characteristics of intracranial aneurysms. The authors have newly established a rat intracranial aneurysm rupture model that features site-specific ruptured and unruptured aneurysms. In the present study the authors examined the time course of changes in the vascular morphology to clarify the mechanisms leading to rupture. Ten-week-old female Sprague-Dawley rats were subjected to hemodynamic changes, hypertension, and ovariectomy. Morphological changes in rupture-prone intracranial arteries were examined under a scanning electron microscope and the association with vascular degradation molecules was investigated. At 2-6 weeks after aneurysm induction, morphological changes and rupture were mainly observed at the posterior cerebral artery; at 7-12 weeks they were seen at the anterior Willis circle including the anterior communicating artery. No aneurysms at the anterior cerebral artery-olfactory artery bifurcation ruptured, suggesting that the inception of morphological changes is site dependent. On week 6, the messenger RNA level of matrix metalloproteinase-9, interleukin-1β, and the ratio of matrix metalloproteinase-9 to the tissue inhibitor of metalloproteinase-2 was significantly higher at the posterior cerebral artery, but not at the anterior communicating artery, of rats with aneurysms than in sham-operated rats. These findings suggest that aneurysm rupture is attributable to significant morphological changes and an increase in degradation molecules. Time-dependent and site-dependent morphological changes and the level of degradation molecules may be indicative of the vulnerability of aneurysms to rupture.
Y Kamio, Takeshi Miyamoto, T Kimura, H Furukkawa, D Zhang, K Yokosuka, M Korai, D Kudo, RJ Lukas, MT Lawton and T Hashimoto : Roles of Nicotine in the Development of Intracranial Aneurysm Rupture., Stroke, Vol.49, No.10, 2445-2452, 2018.
(要約)
Background and Purpose- Tobacco cigarette smoking is considered to be a strong risk factor for intracranial aneurysmal rupture. Nicotine is a major biologically active constituent of tobacco products. Nicotine's interactions with vascular cell nicotinic acetylcholine receptors containing α7 subunits (α7*-nAChR) are thought to promote local inflammation and sustained angiogenesis. In this study, using a mouse intracranial aneurysm model, we assessed potential contributions of nicotine exposure and activation of α7*-nAChR to the development of aneurysmal rupture. Methods- Intracranial aneurysms were induced by a combination of deoxycorticosterone-salt induced hypertension and a single-dose elastase injection into cerebrospinal fluid in mice. Results- Exposure to nicotine or an α7*-nAChR-selective agonist significantly increased aneurysm rupture rate. Coexposure to an α7*-nAChR antagonist abolished nicotine's deleterious effect. In addition, nicotine's promotion of aneurysm rupture was absent in smooth muscle cell-specific α7*-nAChR subunit knockout mice but not in mice lacking α7*-nAChR on endothelial cells or macrophages. Nicotine treatment increased the mRNA levels of vascular endothelial growth factor, platelet-derived growth factor-B, and inflammatory cytokines. α7*-nAChR antagonist reversed nicotine-induced upregulation of these growth factors and cytokines. Conclusions- Our findings indicate that nicotine exposure promotes aneurysmal rupture through actions on vascular smooth muscle cell α7*-nAChR.
Shinji Nagahiro, Yoshiteru Tada, Junichiro Satomi, Tomoya Kinouchi, Kazuyuki Kuwayama, Kenji Yagi, Kohhei Nakajima, Nobuhisa Matsushita, Takeshi Miyamoto, Tadashi Yamaguchi, Kenji Shimada, Masaaki Korai, Hideo Mure, Y Okayama, Takashi Abe, Masafumi Harada, Keiko T. Kitazato and Yasuhisa Kanematsu : Treatment of Unruptured Cerebral Aneurysms with the Mineralocorticoid Receptor Blocker Eplerenone-Pilot Study., Journal of Stroke & Cerebrovascular Diseases, Vol.27, No.8, 2134-2140, 2018.
(要約)
Currently there are no pharmacological therapies for patients with unruptured cerebral aneurysms. Elsewhere we showed that the mineralocorticoid receptor antagonist eplerenone prevented the formation of cerebral aneurysms in our ovariectomized hypertensive aneurysm rat model. The current pilot study evaluated whether it can be used to prevent the growth and rupture of cerebral aneurysms in hypertensive patients. Between August 2011 and May 2014, we enrolled 82 patients with 90 aneurysms in an open-label uncontrolled clinical trial. All provided prior informed consent for inclusion in this study, and all were treated with eplerenone (25-100 mg/d). The primary end points of our study were the rupture and enlargement of the cerebral aneurysms. Of the 82 patients, 80 (88 unruptured aneurysms) were followed for a mean of 21.3 months (153.4 aneurysm-years); 12 patients (15.0%) permanently discontinued taking the drug. One month after the start of eplerenone administration and throughout the follow-up period, eplerenone kept the blood pressure within the normal range. Most notably, no aneurysms smaller than 9 mm ruptured or enlarged. However, of 2 large thrombosed aneurysms, 1 enlarged and the other ruptured. The overall annual rupture rate was .65%; it was 13.16% for aneurysms larger than 10 mm; the overall annual rate for reaching the primary end points was 1.30%. Our observations suggest that eplerenone may help to prevent the growth and rupture of unruptured cerebral aneurysms smaller than 9 mm. To assess its potential long-term clinical benefits, large clinical trials are needed.
Masakazu Kotoda, Hajime Furukawa, Takeshi Miyamoto, Masaaki Korai, Fumiaki Shikata, Atsushi Kuwabara, Xiaoxing Xiong, Caleb Rutledge, Rona G. Giffard and Tomoki Hashimoto : Role of myeloid lineage cell autophagy in ischemic brain injury., Stroke, Vol.49, 1488-1495, 2018.
(要約)
Inflammatory cells play a significant role in secondary injury after ischemic stroke. Recent studies have suggested that a lack of autophagy in myeloid cells causes augmented proinflammatory cytokine release and prolonged inflammation after tissue injury. In this study, we investigated the roles of myeloid cell autophagy in ischemic brain injury. Focal cerebral ischemia was induced via transient middle cerebral artery occlusion in mice with autophagy-deficient myeloid lineage cells (Atg5flox/flox LysMCre+) and in their littermate controls (Atg5flox/flox). Infarct volume, neurological function, inflammatory cell infiltration, and proinflammatory cytokine expression levels were evaluated. Mice lacking autophagy in myeloid lineage cells had a lower survival rate for 14 days than control mice (20% versus 70%; <0.05). Although there was no difference in infarct volume at 12 hours between the 2 groups, mice lacking autophagy in myeloid lineage cells had larger infarct volumes at later time points (3 and 7 days after reperfusion) with worse neurological deficit scores and lower grip test scores. There were a higher number of ionized calcium binding adaptor molecule 1-positive cells and cells expressing M1 marker CD16/32 in mice lacking autophagy in myeloid cells at the later time points. Moreover, these mice had higher expression levels of proinflammatory cytokines at later time points; however, there was no difference in ionized calcium binding adaptor molecule 1-positive cells or mRNA levels of proinflammatory cytokines at the earlier time point (12 hours after reperfusion). These data suggest that the lack of myeloid cell autophagy aggravates secondary injury by augmenting and prolonging inflammation after ischemic stroke without affecting the initial injury.
Hidetsugu Maekawa, Yoshiteru Tada, Kenji Yagi, Takeshi Miyamoto, Kitazato T. Keiko, Masaaki Korai, Junichiro Satomi, Tomoki Hashimoto and Shinji Nagahiro : Bazedoxifene, a selective estrogen receptor modulator, reduces cerebral aneurysm rupture in Ovariectomized rats., Journal of Neuroinflammation, Vol.2, No.14, 197, 2017.
(要約)
Estrogen deficiency is thought to be responsible for the higher frequency of aneurysmal subarachnoid hemorrhage in post- than premenopausal women. Estrogen replacement therapy appears to reduce this risk but is associated with significant side effects. We tested our hypothesis that bazedoxifene, a clinically used selective estrogen receptor (ER) modulator with fewer estrogenic side effects, reduces cerebral aneurysm rupture in a new model of ovariectomized rats. Ten-week-old female Sprague-Dawley rats were subjected to ovariectomy, hemodynamic changes, and hypertension to induce aneurysms (ovariectomized aneurysm rats) and treated with vehicle or with 0.3 or 1.0 mg/kg/day bazedoxifene. They were compared with sham-ovariectomized rats subjected to hypertension and hemodynamic changes (HT rats). The vasoprotective effects of bazedoxifene and the mechanisms underlying its efficacy were analyzed. During 12 weeks of observation, the incidence of aneurysm rupture was 52% in ovariectomized rats. With no effect on the blood pressure, treatment with 0.3 or 1.0 mg/kg/day bazedoxifene lowered this rate to 11 and 17%, almost the same as in HT rats (17%). In ovariectomized rats, the mRNA level of ERα, ERβ, and the tissue inhibitor of metalloproteinase-2 was downregulated in the cerebral artery prone to rupture at 5 weeks after aneurysm induction; the mRNA level of interleukin-1β and the matrix metalloproteinase-9 was upregulated. In HT rats, bazedoxifene restored the mRNA level of ERα and ERβ and decreased the level of interleukin-1β and matrix metalloproteinase-9. These findings suggest that bazedoxifene was protective against aneurysmal rupture by alleviating the vascular inflammation and degradation exacerbated by the decrease in ERα and ERβ. Our observation that bazedoxifene decreased the incidence of aneurysmal rupture in ovariectomized rats warrants further studies to validate this response in humans.
Teruyoshi Kageji, Takeshi Miyamoto, Yumiko Kotani, Tuyoshi Kaji, Yoshimi Bando, Yoshifumi Mizobuchi, Kohhei Nakajima and Shinji Nagahiro : Congenital craniopharyngioma treated by radical surgery: case report and review of the literature, Child's Nervous System, Vol.33, No.2, 357-362, 2016.
(要約)
Craniopharyngiomas are 5-10 % of all pediatric tumors, but are seldomly encountered in the perinatal period. Only seven instances of a truly antenatal diagnosis of a congenital craniopharyngioma that subsequently underwent radical surgery have been reported. We present the case of a patient who received the diagnosis of a suprasellar tumor during the prenatal period and received radical surgery. We report a case of a neonatal craniopharyngioma treated surgically. The pregnancy progressed uneventfully until a routine ultrasound at 37 weeks of gestation showed a 15 × 15 mm high echoic mass in the center of the fetal head. Neonatal Gd-enhanced T1-weighted MRI at 5 days of life showed a homogenously enhanced mass (16×22×15 mm) in the sellar and suprasellar lesion. As the tumor showed rapid growth at the 3rd month of life, the patient underwent a surgical treatment and the mass was totally removed. Three years later, the physical and mental development of the patient was normal, and Gd-MRI studies showed no tumor recurrence. The present case is the eighth case of a truly antenatal diagnosis of a craniopharyngioma that underwent successful radical surgery. Craniopharyngioma is a benign tumor and thought to be a slow growing tumor in childhood. The results of radical surgery were very poor, and the mortality and morbidity rates were high in the previous reports due to the huge size of tumor at operation. The present case demonstrated the rapid growth in short interval of Gd-MRI. This is the first report of tumor kinetics of congenital craniopharyngioma with previous reports. The calculated tumor doubling time in our case was 37 days.
Masaaki Korai, 北里 慶子, Yoshiteru Tada, Takeshi Miyamoto, Kenji Shimada, Nobuhisa Matsushita, Yasuhisa Kanematsu, Junichiro Satomi, 橋本 友紀 and Shinji Nagahiro : Hyperhomocysteinemia induced by excessive methionine intake promotes rupture of cerebral aneurysms in ovariectomized rats, Journal of Neuroinflammation, Vol.13, No.1, 165, 2016.
(要約)
Hyperhomocysteinemia (HHcy) is associated with inflammation and a rise in the expression of matrix metalloproteinase-9 (MMP-9) in the vascular wall. However, the role of HHcy in the growth and rupture of cerebral aneurysms remains unclear. Thirteen-week-old female Sprague-Dawley rats were subject to bilateral ovariectomy and ligation of the right common carotid artery and fed an 8 % high-salt diet to induce cerebral aneurysms. Two weeks later, they underwent ligation of the bilateral posterior renal arteries. They were divided into two groups and methionine (MET) was or was not added to their drinking water. In another set of experiments, the role of folic acid (FA) against cerebral aneurysms was assessed. During a 12-week observation period, subarachnoid hemorrhage due to aneurysm rupture was observed at the anterior communicating artery (AcomA) or the posterior half of the circle of Willis. HHcy induced by excessive MET intake significantly increased the incidence of ruptured aneurysms at 6-8 weeks. At the AcomA of rats treated with MET, we observed the promotion of aneurysmal growth and infiltration by M1 macrophages. Furthermore, the mRNA level of MMP-9, the ratio of MMP-9 to the tissue inhibitor of metalloproteinase-2, and the level of interleukin-6 were higher in these rats. Treatment with FA abolished the effect of MET, suggesting that the inflammatory response and vascular degradation at the AcomA is attributable to HHcy due to excessive MET intake. We first demonstrate that in hypertensive ovariectomized rats, HHcy induced by excessive MET intake may be associated with the propensity of the aneurysm wall to rupture.
Takeshi Miyamoto, DK Kung, KT Kitazato, Kenji Yagi, Kenji Shimada, Yoshiteru Tada, Masaaki Korai, Yoshitaka Kurashiki, Tomoya Kinouchi, Yasuhisa Kanematsu, Junichiro Satomi, T Hashimoto and Shinji Nagahiro : Site-specific elevation of interleukin-1β and matrix metalloproteinase-9 in the Willis circle by hemodynamic changes is associated with rupture in a novel rat cerebral aneurysm model, Journal of Cerebral Blood Flow and Metabolism, Vol.37, No.8, 2795-2805, 2016.
(要約)
The pathogenesis of subarachnoid hemorrhage remains unclear. No models of cerebral aneurysms elicited solely by surgical procedures and diet have been established. Elsewhere we reported that only few rats in our original rat aneurysm model manifested rupture at the anterior and posterior Willis circle and that many harbored unruptured aneurysms at the anterior cerebral artery-olfactory artery bifurcation. This suggests that rupture was site-specific. To test our hypothesis that a site-specific response to hemodynamic changes is associated with aneurysmal rupture, we modified our original aneurysm model by altering the hemodynamics. During 90-day observation, the incidence of ruptured aneurysms at the anterior and posterior Willis circle was significantly increased and the high incidence of unruptured aneurysms at the anterior cerebral artery-olfactory artery persisted. This phenomenon was associated with an increase in the blood flow volume. Notably, the level of matrix metalloproteinase-9 associated with interleukin-1β was augmented by the increase in the blood flow volume, suggesting that these molecules exacerbated the vulnerability of the aneurysmal wall. The current study first demonstrates that a site-specific increase in interleukin-1β and matrix metalloproteinase-9 elicited by hemodynamic changes is associated with rupture. Our novel rat model of rupture may help to develop pharmaceutical approaches to prevent rupture.
Manabu Sumiyoshi, T Keiko Kitazato, Kenji Yagi, Takeshi Miyamoto, Yoshitaka Kurashiki, Nobuhisa Matsushita, Tomoya Kinouchi, Kazuyuki Kuwayama, Junichiro Satomi and Shinji Nagahiro : The accumulation of brain water-free sodium is associated with ischemic damage independent of the blood pressure in female rats, Brain Research, Vol.1616, 37-44, 2015.
(要約)
Estrogen deficiency worsens ischemic stroke outcomes. In ovariectomized (OVX(+)) rats fed a high-salt diet (HSD), an increase in the body Na(+)/water ratio, which characterizes water-free Na(+) accumulation, was associated with detrimental vascular effects independent of the blood pressure (BP). We hypothesized that an increase in brain water-free Na(+) accumulation is associated with ischemic brain damage in OVX(+)/HSD rats. To test our hypothesis we divided female Wistar rats into 4 groups, OVX(+) and OVX(-) rats fed HSD or a normal diet (ND), and subjected them to transient cerebral ischemia. The brain Na(+)/water ratio was increased even in OVX(+)/ND rats and augmented in OVX(+)/HSD rats. The increase in the brain Na(+)/water ratio was positively correlated with expansion of the cortical infarct volume without affecting the BP. Interestingly, OVX(+) was associated with the decreased expression of ATP1α3, a subtype of the Na(+) efflux pump. HSD increased the expression of brain Na(+) influx-related molecules and the mineralocorticoid receptor (MR). The pretreatment of OVX(+)/HSD rats with the MR antagonist eplerenone reduced brain water-free Na(+) accumulation, up-regulated ATP1α3, down-regulated MR, and reduced the cortical infarct volume. Our findings show that the increase in the brain Na(+)/water ratio elicited by estrogen deficiency or HSD is associated with ischemic brain damage BP-independently, suggesting the importance of regulating the accumulation of brain water-free Na(+). The up-regulation of ATP1α3 and the down-regulation of MR may provide a promising therapeutic strategy to attenuate ischemic brain damage in postmenopausal women.
Manabu Sumiyoshi, Junichiro Satomi, KT Kitazato, Kenji Yagi, Yoshitaka Kurashiki, Masaaki Korai, Takeshi Miyamoto, Kazuyuki Kuwayama and Shinji Nagahiro : PPAR-dependent- and -independent inhibition of the HMGB1/TLR9 Pathway by EPA attenuates ischemic brain damage in ovariectomized rats, Journal of Stroke & Cerebrovascular Diseases, Vol.24, No.6, 1187-1195, 2015.
(要約)
High mobility group box 1 (HMGB1) elevation after cerebral ischemia activates inflammatory pathways via receptors such as the receptor for advanced glycation end products (RAGE) and toll-like receptors (TLRs) and leads to brain damage. Eicosapentaenoic acid (EPA), a peroxisome proliferator-activated receptor gamma (PPARγ) agonist, attenuates postischemic inflammation and brain damage in male animals. However, postischemic HMGB1 signaling and the effects of EPA on ovariectomized (OVX(+)) rats remain unclear. We hypothesized that EPA attenuates brain damage in OVX(+) rats via the inhibition of HMGB1 signaling in a PPARγ-dependent manner. Seven-week-old female Sprague-Dawley rats were divided into 3 groups; nonovariectomized (OVX(-)) rats and EPA-treated and EPA-untreated OVX(+) rats before cerebral ischemia induction. Another set of EPA-treated OVX(+) rats was injected with the PPARγ inhibitor GW9662. OVX(+) decreased the messenger RNA level of PPARγ and increased that of HMGB1, RAGE, TLR9, and tumor necrosis factor alpha (TNFα) in parallel with ischemic brain damage. EPA restored the PPARγ expression, downregulated the HMGB1 signal-related molecules, and attenuated the ischemic brain damage. Neither OVX(+) nor EPA affected the expression of TLR2 or TLR4. Interestingly, GW9662 partially abrogated the EPA-induced neuroprotection and the downregulation of RAGE and TLR9. In contrast, GW9662 did not affect HMGB1 or TNFα. These results suggest that EPA exerts PPARγ-dependent and PPARγ-independent effects on postischemic HMGB1/TLR9 pathway. The cortical infarct volume exacerbated by OVX(+) is associated with the upregulation of the HMGB1/TLR9 pathway. Suppression of this pathway may help to limit ischemic brain damage in postmenopausal women.
Izumi Yamaguchi, Yasuhisa Kanematsu, Kenji Shimada, Nobuaki Yamamoto, Masaaki Korai, Kazuhisa Miyake, Takeshi Miyamoto, Shu Sogabe, Eiji Shikata, Manabu Ishihara, Yuki Yamamoto, Kazutaka KURODA and Yasushi Takagi : Evaluation of Serial Intra-Arterial Indocyanine Green Videoangiography in the Surgical Treatment of Cranial and Craniocervical Junction Arteriovenous Fistulae: A Case Series, Operative Neurosurgery, Vol.25, No.3, 292-300, 2023.
(要約)
Intravenous indocyanine green (IV-ICG) videoangiography is commonly performed to detect blood flow in the microscopic view. However, intra-arterial ICG (IA-ICG) videoangiography provides high-contrast imaging, repeatability within a short period of time, and clear-cut separation of the arterial and venous phases compared with IV-ICG. These features are useful for detecting retrograde venous drainage (RVD) and shunt occlusion in arteriovenous fistulae (AVF) surgery. This study aimed to investigate whether IA-ICG videoangiography can be repeatable within a short period of time and be useful for detecting RVD and shunt occlusion in cranial- and craniocervical junction (CCJ)-AVF surgery. Between January 2012 and December 2022, 50 patients were treated with endovascular or surgical intervention for cranial- and CCJ-AVF at Tokushima University Hospital. Of these, 5 patients (6 lesions) underwent open surgery with IA-ICG videoangiography in a hybrid operating room. We analyzed the data of these 5 patients (6 lesions). There were 4/patient (median, range 2-12) and 3.5/lesion (median, range 2-10) intraoperative IA-ICG runs. IA-ICG videoangiography detected RVD in all patients. Clearance of IA-ICG-induced fluorescence was achieved within 30 seconds in all patients at each region of interest. After the disconnection of the fistulae, IA-ICG videoangiography and intraoperative digital subtraction angiography (DSA) confirmed the disappearance of RVD in all patients. There were no complications associated with IA-ICG videoangiography. This study showed that IA-ICG videoangiography is repeatable within a short period of time before and after obliteration and can be useful for detecting RVD and shunt occlusion in cranial- and CCJ-AVF surgery. IA-ICG videoangiography also allows intraoperative DSA studies in a hybrid operating room. Considering the recent advancements in hybrid operating rooms, combining IA-ICG videoangiography with intraoperative DSA is a useful strategy for cranial- and CCJ-AVF surgery.
Tadashi Yamaguchi, Keiko T Kitazato, Eiji Shikata, Idumi Yamaguchi, Takeshi Miyamoto, Masaaki Korai, Kenji Shimada, Yoshiteru Tada, Yasuhisa Kanematsu and Yasushi Takagi : Pro-inflammatory response promoted by Porphyromonas gingivalis lipopolysaccharide enhances the rupture of experimental intracranial aneurysms., Brain and Brain PET2019, Yokohama, Jul. 2019.
2.
Tadashi Yamaguchi, Takeshi Miyamoto, Masaaki Korai, Kenji Shimada, Yoshiteru Tada, Yasuhisa Kanematsu, Junichiro Satomi, Shinji Nagahiro and Yasushi Takagi : Estrogen deficiency activates inflammasome in a rat model of intracranial aneurysms, 11th World Stroke Congress 2018, Montreal, Oct. 2018.
3.
Takeshi Miyamoto, Yoshiteru Tada, Kenji Shimada, Kenji Yagi, Masaaki Korai, Hidetsugu Maekawa, Tadashi Yamaguchi, Syotaro Soshioka, Tomoya Kinouchi, Yasuhisa Kanematsu, Junichiro Satomi and Shinji Nagahiro : Pro-inflammatory Response Elicited by Porphyromonas Gingivalis Lipopolysaccharide Exacerbates the Rupture of Experimental Cerebral Aneurysms, International Stroke Conference 2017, Houston, Feb. 2017.
4.
Takeshi Miyamoto, Keiko Kitazato, Hidetsugu Maekawa, Tadashi Yamaguchi, Kenji Shimada, Kenji Yagi, Yoshiteru Tada, Yoshitaka Kurashiki, syotaro Yoshioka, Yasuhisa Kanematsu, Junichiro Satomi and Shinji Nagahiro : Porphyromonas gingivalis lipopolysaccharide enhances the rupture of intracranial aneurysms in rats, 25th European Stroke Conference, Apr. 2016.
5.
Yoshitaka Kurashiki, Keiko Kitazato, Kenji Shimada, Kenji Yagi, Yoshiteru Tada, Tomoya Kinouchi, Manabu Sumiyoshi, Takeshi Miyamoto, Tadashi Yamaguchi, Junichiro Satomi, Yoshihiro Uto and Shinji Nagahiro : Activation of M2 macrophages in the late phase of cerebral ischemia may contribute to phagocytosis of infarct area and neurogenesis, 25th European Stroke Conference, Apr. 2016.
6.
Syotaro Yoshioka, Yoshiteru Tada, Junichiro Satomi, Kenji Yagi, Koji Naruishi, Kazuyuki Kuwayama, Keiko Kitazato, Takeshi Miyamoto, Yasuhisa Kanematsu, Masafumi Harada, Toshihiko Nagata and Shinji Nagahiro : Impact of Periodontal Disease and Bacteria on Intracranial Aneurysms, International Stroke Conference 2016, Los Angeles, Feb. 2016.
7.
Junichiro Satomi, Yoshiteru Tada, Yasuhisa Kanematsu, Kazuyuki Kuwayama, Kenji Yagi, Tomoya Kinouchi, Kohhei Nakajima, Nobuhisa Matsushita, Takeshi Miyamoto, Tadashi Yamaguchi, Masaaki Korai, Hideo Mure, Keiko Kitazato and Shinji Nagahiro : A Pilot Study of the Mineralocorticoid Receptor Blocker Eplerenone in Hypertensive Patients with Unruptured Cerebral Aneurysms, International Stroke Conference 2016, Los Angeles, Feb. 2016.
8.
Hidetsugu Maekawa, Takeshi Miyamoto, Keiko T Kitazato and Shinji Nagahiro : 3D structure of vasa vasorum in thrombosed rat cerebral aneurysms, ABCWIN Seminar, Paris, Jan. 2016.