研究者業績

草鹿 元

クサカ ゲン  (Gen Kusaka)

基本情報

所属
自治医科大学 医学部 総合医学第2講座  教授

J-GLOBAL ID
201401089608786952
researchmap会員ID
B000239152

外部リンク

論文

 17
  • Kamochi H, Kusaka G, Ishikawa M, Ishikawa S, Tanaka Y
    Neurologia medico-chirurgica 53 217-220 2013年  査読有り
  • Takeharu Kanazawa, Yusuke Watanabe, Mariko Hara, Akihiro Shinnabe, Gen Kusaka, Takanori Murayama, Yukiko Iino
    AMERICAN JOURNAL OF OTOLARYNGOLOGY 33(3) 303-307 2012年5月  査読有り
    Purpose: Laryngeal framework surgery is usually performed under local anesthesia but cannot be tolerated by some patients. To develop a new procedure for these patients, we evaluated voice outcomes after arytenoid adduction combined with medialization laryngoplasty under general anesthesia using a laryngeal mask airway (LMA) for unilateral vocal cord paralysis. Materials and Methods: Eleven consecutive patients with severe unilateral vocal cord paralysis, with a maximum phonation time of less than 5 seconds, underwent arytenoid adduction combined with medialization laryngoplasty under general anesthesia using an LMA. Each paralyzed vocal cord was observed by intraoperative videolaryngoscopy. The vocal cord was moved to the position where the best vocal outcome could be expected, according to 3 parameters obtained from glottal images. Results: All patients achieved a maximum phonation time of more than 11 seconds. The mean airflow rate, which ranged from 550 to 1000 mL/s before surgery, improved to less than 390 mL/s. Perceptual evaluation using the grade, roughness, breathiness, asthenia and strain scale also improved significantly. Conclusions: These results were equivalent to those of previous reports of surgeries performed under local anesthesia. Intraoperative endoscopic vocal cord observation through the LMA may have contributed to the positive results. (C) 2012 Elsevier Inc. All rights reserved.
  • Kanazawa T, Sarukawa S, Fukushima H, Takeoda S, Kusaka G, Ichimura K
    Annals of vascular diseases 4 189-195 2011年  査読有り
  • Mami Ishikawa, Gen Kusaka, Kouichi Takashima, Haruna Kamochi, Soji Shinoda
    JOURNAL OF CLINICAL NEUROSCIENCE 17(8) 1053-1056 2010年8月  査読有り
    A 54-year-old man presented with an intracranial schwannoma of the hypoglossal nerve between the medulla and the left hypoglossal canal. The condylar fossa approach was used with intra-operative electromyography (EMG) monitoring of the lower cranial nerves. The tumor was then removed carefully without decreasing the tongue EMG responses. EMG monitoring enabled us to remove the tumor while maintaining the function of the hypoglossal nerve. Tongue EMG was easily recorded by stimulating the hypoglossal nerve fibers, which was useful in identifying the hypoglossal nerve and evaluating its function. This suggests that tongue EMG is a useful monitoring tool to enhance neurological outcome following removal of tumors in this region. (C) 2009 Elsevier Ltd. All rights reserved.
  • Mami Ishikawa, Koichi Takashima, Haruna Kamochi, Gen Kusaka, Sohji Shinoda, Eiju Watanabe
    NEUROLOGICAL RESEARCH 32(6) 656-660 2010年7月  査読有り
    Botulinum toxin type A (BTX) injection into the orbicularis oculi muscle is an effective treatment for patients with hemifacial spasm (HFS). The objectives of this study were to investigate the effect of this treatment on HFS, in particular the associated hyperexcitability of the facial motor nucleus, and to discuss the potential mechanism of HFS. F waves in the mentalis muscle were examined before, 2 and 6 weeks after the BTX treatment of only the orbicularis oculi muscle in ten patients with HFS. F/M ratio, duration of F waves and frequency of F waves decreased significantly after the BTX treatment compared with those before the BTX treatment. These findings demonstrate that the excitability of the facial motonucleus decreases after BTX treatment of the orbicularis oculi muscle. From these results, we hypothesize that the trigeminal afferent input and the cortical control contribute to the hyperexcitability of the facial motor nucleus in patients with HFS. This warrants further investigation into the pathophysiology of HFS.
  • Mami Ishikawa, Gen Kusaka, Kouichi Takashima, Haruna Kamochi, Soji Shinoda
    CLINICAL NEUROLOGY AND NEUROSURGERY 112(5) 450-453 2010年6月  査読有り
    Under an operative view, an aneurysm of the vertebral artery is located behind the lower cranial nerves. To prevent neurological deficits we employed electrophysiological monitoring while clipping an aneurysm of the vertebral artery. A 64-year-old woman had suffered a sudden severe headache in the morning. Computed tomography (CT) revealed a subarachnoid hemorrhage (SAH) and CT angiography revealed an aneurysm at a branching point of the left vertebral artery. The condylar fossa approach was taken while recording electromyography (EMG) of the lower cranial nerves. The aneurysm was located just behind the hypoglossal nerve and could not be clipped without strong traction of the hypoglossal nerve. Therefore, the hypoglossal nerve was divided to separate the lower two bundles of the hypoglossal nerve from the other bundles, and the clip was applied to the aneurysm between the nerve bundles without any change of the tongue EMG. The patient went home 10 days after operation with no neurological deficit. In conclusion, we report a case of a ruptured aneurysm of a vertebral artery, which was clipped while monitoring the lower cranial nerves. Tongue EMG monitoring enabled us to clip the aneurysm without nerve injury and revealed that the hypoglossal nerve near the hypoglossal canal can be divided into several bands without neurological deficit. (C) 2010 Elsevier B.V. All rights reserved.
  • Mami Ishikawa, Gen Kusaka, Noriyuki Yamaguchi, Eiichi Sekizuka, Hiromichi Nakadate, Haruyuki Minamitani, Soji Shinoda, Eiju Watanabe
    NEUROSURGERY 64(3) 546-553 2009年3月  査読有り
    OBJECTIVE: Pathophysiology after subarachnoid hemorrhage (SAH) caused by aneurysmal rupture has not been well examined. The purpose of this study was to observe platelet-leukocyte-endothelial cell interactions as indexes of inflammatory and prothrombogenic responses in the acute phase of SAH, using an in vivo cranial window method. METHODS: Subarachnoid hemorrhage was induced in C57Bl/6j mice by using the endovascular perforation method. Intravital microscopy was used to monitor the rolling and adhesion of platelets and leukocytes that were labeled with different fluorochromes. Regional cerebral blood flow was measured with laser Doppler flowmetry. The platelet-leukocyte-endothelial cell interactions were observed 30 minutes, 2 hours, and 8 hours after SAH. The effect of P-selectin antibody and apocynin, an inhibitor of nicotinamide adenine dinucleotide phosphate oxidase, on these responses was examined at 2 hours after SAH, and compared with a different SAH model in which autologous blood was injected into the foramen magna. RESULTS: SAH was accompanied by a 60% decrease in regional cerebral blood flow, whereas no changes in regional cerebral blood flow were observed on the contralateral side. SAH elicited time- and size-dependent increases in rolling and adherent platelets and leukocytes in cerebral venules. All of these interactions were attenuated by treatment with a P-selectin antibody or apocynin. There was no significant blood cell recruitment observed in the blood-injected SAH model. CONCLUSION: SAH at the skull base induced P-selectin- and oxygen radical-mediated platelet-leukocyte-endothelial cell interactions in venules at the cerebral surface. These early inflammatory and prothrombogenic responses may cause a whole-brain injury immediately after SAH.
  • Takashima K, Takahashi M, Yubune N, Inaba N, Omoto K, Kawano M, Sakurabayashi I, Ishikawa M, Kusaka G, Shinoda S
    Rinsho byori. The Japanese journal of clinical pathology 56 475-485 2008年6月  査読有り
  • Tomoyuki Saito, Yasutaka Watanabe, Miho Yuzawa, Takako Saito, Hiroyuki Tamemoto, Hisashi Suzuki, Gen Kusaka, Yoshio Omori, Soji Shinoda, Masanobu Kawakami, San-e Ishikawa
    INTERNAL MEDICINE 46(10) 653-656 2007年  査読有り
    A 50-year-old man was admitted to determine the pathogenesis of hyponatremia. He had a poor appetite and was easily fatigued. Physical findings showed that he was conscious and alert. He had neither dry skin or tongue, nor pretibial edema. Laboratory data revealed that the serum sodium level was 110 mmol/l; plasma osmolality, 238 mmol/kg; and urinary osmolality, 417 mmol/kg. Plasma arginine vasopressin was 0.5 pg/ml despite plasma osmolality of 242 mmol/ kg. An acute water load showed impaired water excretion, as percent excretion of water load was 30% and minimal urinary osmolality was 642 mmol/kg. Serum prolactin was 254 ng/ml, and anterior pituitary hormones of ACTH, TSH and GH were in the normal ranges. Brain magnetic resonance imaging (MRI) showed a pituitary tumor with a size of 20 x 22 x 21 mm and it pushed a pituitary stalk upward. Immunohistochemistry revealed prolactinoma. After the adenomectomy, serum sodium level has been kept normal with free access to water intake. The present study indicates that syndrome of inappropriate secretion of antidiuretic hormone (SIADH) is manifested in association with pituitary macroadenoma of prolactinoma.
  • M Yamaguchi, JW Calvert, G Kusaka, JH Zhang
    STROKE 36(10) 2212-2214 2005年10月  査読有り
    Background and Purpose-We report a modified 4-vessel occlusion (4VO) rat model. Method-We used a 1-stage anterior approach for making bilateral hemispheric ischemia. Results-Modified 4VO method decreased cerebral blood flow to 12% to 14% of baseline levels. Conclusion-This modified 4VO method is a minimally invasive, quick, reliable procedure for producing ischemic changes.
  • Patwardhan RV, Calvert JW, Besio W, Kusaka G, Kusaka I, Zhang J, Nanda A
    Frontiers in bioscience : a journal and virtual library 10 3009-3012 2005年9月  査読有り
  • Patwardhan RV, Besio W, Calvert JW, Kusaka G, Kusaka I, Zhang J, Nanda A
    Frontiers in bioscience : a journal and virtual library 10 3013-3019 2005年9月  査読有り
  • G Kusaka, T Ishikawa, A Nanda, TN Granger, JH Zhang
    JOURNAL OF CEREBRAL BLOOD FLOW AND METABOLISM 24(8) 916-925 2004年8月  査読有り
    Few studies have examined the signaling pathways that contribute to early brain injury after subarachnoid hemorrhage (SAH). Using a rat SAH model, the authors explored the role of vascular endothelial growth factor (VEGF) and mitogen-activation protein kinase (MAPK) in early brain injury. Male Sprague-Dawley rats (n = 172) weighing 300 to 350 g were used for the experimental SAH model, which was induced by puncturing the bifurcation of the left anterior cerebral and middle cerebral arteries. The blood-brain barrier (BBB), brain edema, intracranial pressure, and mortality were evaluated at 24 hours after SAH. The phosphorylation of VEGF and different MAPK subgroups (ERK 1/2, p3 8, and JNK) were examined in both the cortex and the major cerebral arteries. Experimental SAH increased intracranial pressure, BBB permeability, and brain edema and produced high mortality. SAH induced phosphorylation of VEGF and MAPKs in the cerebral arteries and, to a lesser degree, in the cortex. PPI, an Src-family kinase inhibitor, reduced BBB permeability, brain edema, and mortality and decreased the phosphorylation of VEGF and MAPKs. The authors conclude that VEGF contributes to early brain injury after SAH by enhancing the activation of the MAPK pathways, and that the inhibition of these pathways might offer new treatment strategies for SAH.
  • Kusaka, I, G Kusaka, C Zhou, M Ishikawa, A Nanda, DN Granger, JH Zhang, JP Tang
    AMERICAN JOURNAL OF PHYSIOLOGY-HEART AND CIRCULATORY PHYSIOLOGY 286(6) H2442-H2451 2004年6月  査読有り
    The objective of the present study was to examine the role of the angiotensin II type 1 receptor (AT(1)-R) in the diabetes-aggravated oxidative stress and brain injury observed in a rat model of combined diabetes and focal cerebral ischemia. Diabetes was induced by an injection of streptozotoxin (STZ; 55 mg/kg iv) at 8 wk of age. Two weeks after the induction of diabetes, some animals received continuous subcutaneous infusion of the AT(1)-R antagonist candesartan (0.5 mg.kg(-1).day(-1)) for 14 days. Focal cerebral ischemia, induced by middle cerebral artery occlusion/reperfusion (MCAO), was conducted at 4 wk after STZ injection. Male Sprague-Dawley rats (n = 189) were divided into five groups: normal control, diabetes, MCAO, diabetes + MCAO, and diabetes + MCAO + candesartan. The major observations were that 1) MCAO produced typical cerebral infarction and neurological deficits at 24 h that were accompanied by elevation of NAD(P)H oxidase gp91(phox) and p22(phox) mRNAs, and lipid hydroperoxide production in the ipsilateral hemisphere; 2) diabetes enhanced NAD( P) H oxidase gp91phox and p22phox mRNA expression, potentiated lipid peroxidation, aggravated neurological deficits, and enlarged cerebral infarction; and 3) candesartan reduced the expression of gp91phox and p22phox, decreased lipid peroxidation, lessened cerebral infarction, and improved the neurological outcome. We conclude that diabetes exaggerates the oxidative stress, NAD( P) H oxidase induction, and brain injury induced by focal cerebral ischemia. The diabetes-aggravated brain injury involves AT(1)-Rs. We have shown for the first time that candesartan reduces brain injury in a combined model of diabetes and cerebral ischemia.
  • G Kusaka, JW Calvert, C Smelley, A Nanda, JH Zhang
    JOURNAL OF NEUROSCIENCE METHODS 135(1-2) 121-127 2004年5月  査読有り
    Objective: Monitoring cerebrospinal fluid pressure or intracranial pressure (ICP) is crucial in the study of neurosurgical disorders. In the present study. we report a new lumbar method for monitoring ICP in rats. Methods: A PE10 catheter connected to a pressure transducer was placed into the subarachnoid space of L5 through the duramater after laminectomy to record lumbar cerebrospinal fluid pressure (lumbar-ICP). ICP at the cisterna magna (cistema-ICP) was recorded simultaneously via a catheter in the subarachnoid space at the cisterna magna. Eighteen anesthetized adult male S-D rats were subjected to baseline recording followed by either experimental subarachnoid hemorrhage (SAH) induced by intravascular puncture method or experimental intracerebral hemorrhage (ICH) induced by blood injection with a stereotaxic system. Results.. Baseline lurnbar-ICP and cisterna-ICP varied between 6 and 8 mmHg, and respiratory variation could be detected. A similar acute response to SAH was recorded in both the lumbar-ICP and cisterna-ICP in all rats. In rats Subjected to SAH, the lumbar catheter continuously and accurately monitored lumbar-ICP and reliable pressure tracings were obtained for up to 24 It after SAH. However, continued cistema-ICP monitoring was abandoned in two rats in the cisterna magna method due to obstruction of the catheter by blood clots (hematoma). Conclusion: This new lumbar-ICP method is simple, safe, easy. and reliable in rats. Continued lumbar-ICP measurements provided monitoring, for up to 24 h after experimental manipulation. (C) 2003 Elsevier B.V. All rights reserved.
  • CM Zhou, M Yamaguchi, G Kusaka, C Schonholz, A Nanda, JH Zhang
    JOURNAL OF CEREBRAL BLOOD FLOW AND METABOLISM 24(4) 419-431 2004年4月  査読有り
    Apoptosis in the endothelium of major cerebral arteries may play a role in the initiation and maintenance of cerebral vasospasm after subarachnoid hemorrhage (SAH). We tested the therapeutic effect of caspase inhibitors on endothelial apoptosis and on cerebral vasospasm in an established dog double-hemorrhage model. Thirty-one mongrel dogs were divided into five groups: control; SAH; SAH treated with vehicle [DMSO]; SAH treated with Ac-DEVD-CHO [a specific caspase-3 inhibitor] and SAH treated with Z-VAD-FMK [a broad caspase inhibitor]. The inhibitors (100 muM) were injected into the cisterna magna daily front Day 0 through Day 3. Angiography was performed on Day 0 and Day 7. Histology, TUNEL staining, and immunohistochemistry were conducted on basilar arteries collected on Day 7 after SAH. Positive staining of TUNEL, poly(ADP)-ribose polymerase (PARP), caspase-3, and caspase-8 was observed in the endothelial cells of the spastic arteries. Double fluorescence labeling demonstrated colocalization of TUNEL with caspase-3 and TNFalpha-receptor-1 (TNFR I). Ac-DEVD-CHO and Z-VAD-FMK prevented endothelial apoptosis and reduced angiographic vasospasm. The mechanism of apoptosis in endothelial cells involves TNFR1 and the caspase-8 and caspase-3 pathways. Caspase inhibitors may have potential in the treatment of cerebral vasospasm..
  • G Kusaka, H Kimura, Kusaka, I, E Perkins, A Nanda, JH Zhang
    JOURNAL OF NEUROSURGERY 99(2) 383-390 2003年8月  査読有り
    Object. Mitogen-activated protein kinase (MAPK) has been implicated in cerebral vasospasm after subarachnoid hemorrhage (SAH). This study was conducted to investigate whether Src tyrosine kinase, an upstream regulator of MAPK, is involved in cerebral vasospasm. Methods. An established canine double-hemorrhage model was used. Twenty-four dogs were divided into four groups: control, vehicle-treated, Src inhibitor PP2-treated, and Src inhibitor damnacanthal-treated groups. Vehicle (dimethyl sulfoxide), PP2, or damnacanthal was injected daily into the cisterna magna of IS dogs at 3 to 6 days after induction of SAH. Angiography was performed on Day 0 (the day on which the first blood injection was administered to induce SAH) and on Day 7. Western blot analysis of Src and MAPK activation in basilar arteries (BAs) collected on Day 7 post-SAH was performed. Severe vasospasm was observed in the BAs of vehicle-treated dogs. Mild vasospasm was observed in all dogs treated with Src inhibitors. Phosphorylated Src and MAPK were increased after SAH and activation of these kinases in the BAs was abolished by PP2 and damnacanthal. Conclusions. The tyrosine kinase Src is an important upstream regulator of MAPK, and inhibition of Src might offer a new therapy in the management of cerebral vasospasm.

MISC

 6
  • 石川 眞実, 草鹿 元, 篠田 宗次, 山口 則之, 渡辺 英寿
    脳卒中の外科 = Surgery for cerebral stroke 37(2) 93-99 2009年3月31日  
    Pathophysiology after subarachnoid hemorrhage (SAH) has not been well examined. We observed platelet-leukocyte-endothelial cell interactions as indexes of inflammatory and prothrombogenic responses in the acute phase of SAH, using an in vivo cranial window method. <br> Subarachnoid hemorrhage was induced in C57Bl/6J mice by the endovascular perforation method. Regional cerebral blood flow (rCBF) was measured with laser-doppler flowmetry. The platelet-leukocyte-endothelial cell interactions were observed with an intravital microscopy 30 minutes, 2 hours, and 8 hours after SAH. The effect of P-selectin antibody and apocynin on these responses was examined, and compared with a different SAH model, in which autologous blood was injected into the foramen magnum. <br> SAH was accompanied by a 60% decrease in rCBF, whereas no changes in rCBF were observed on the contralateral side. SAH elicited time- and size-dependent increases in rolling and adherent platelets and leukocytes in cerebral venules, attenuated by a P-selectin antibody, or apocynin. There was no significant blood cell recruitment in the blood-injected SAH model. <br> SAH at the skull base induced P-selectin- and oxygen radical-mediated platelet-leukocyte-endothelial cell interactions in venules at the cerebral surface. These early inflammatory and prothrombogenic responses may cause a whole brain injury immediately after SAH.<br>
  • 高嶋 浩一, 高橋 真由美, 湯舟 憲雄, 稲葉 信夫, 尾本 きよか, 河野 幹彦, 櫻林 郁之介, 石川 眞実, 草鹿 元, 篠田 宗次
    臨床病理 56(6) 475-485 2008年6月25日  
  • 鈴木 尚, 草鹿 元, 大森 義男, 篠田 宗次
    自治医科大学紀要 29 181-186 2006年12月1日  
    ラトケ嚢胞に伴って発症する下垂体卒中は極めて稀である。今回我々は,ラトケ嚢胞に伴った下垂体卒中の2症例を経験した。症例は次の通りである。症例1:28歳男性で突然の頭痛と嘔気,めまいにて発症。MRIでトルコ鞍内から鞍上部に混合信号域を認め,出血を伴った嚢胞性病変が疑われた。経蝶形骨洞的腫瘍摘出術施行し,術後症状は消失した。症例2:32歳女性。鎮痛剤無効の頭痛のためMRI施行し,同様にトルコ鞍内に出血が疑われたため,経蝶形骨洞的腫瘍摘出術施行した。術後症状は消失し,病理所見はいずれも出血を伴ったラトケ嚢胞であった。下垂体卒中は主に下垂体腺腫に伴って生じることが多く,ラトケ嚢胞に伴った下垂体卒中の報告は,これまで渉猟しえた文献では,本2症例を含め9症例のみであった。ラトケ嚢胞からの出血の機序や治療方法など,我々の経験も含め若干の文献学的考察を加え報告する。
  • 鈴木 尚, 神田 大, 草鹿 元, 大森 義男, 石川 三衛, 篠田 宗次
    日本内分泌学会雑誌 81 164-165 2005年9月20日  
  • 宮脇 貴裕, 草鹿 元, 篠田 宗次, 増澤 紀男
    脳神経外科ジャーナル 10(6) 409-413 2001年  
    悪性リンパ腫が脊髄髄内に原発することはきわめて稀といわれている.われわれは41歳, 男性で, 両下肢の温痛覚障害, 両下肢の筋力低下, 膀胱直腸障害で発症した1例を報告する.MRIを含む画像所見では, Th7〜9に及ぶGd-DTPAにて増強される腫瘍を認め, 脊髄髄内腫瘍の診断で同部位の椎弓切除と生検術を施行した.病理組織所見はB-cell type diffuse large non-Hodgkin malignant lymphomaであった.発症から緩徐な経過をとり, ステロイドが効果のなかったことが診断まで時間を要した原因と思われた稀な脊髄悪性リンパ腫を経験した.