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Yamamoto D, Koizumi H, Ishima D, Kuroda H, Shibahara I, Niki J, Miyasaka K, Watanabe T, Kondo R, Kumabe T. Angiographic Characterization of the External Carotid Artery: Special Attention to Variations in Branching Patterns. TOHOKU J EXP MED 2019; 249:185-192. [DOI: 10.1620/tjem.249.185] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Koizumi H, Ogawa T. Rapid and Sensitive Method to Measure Premature Yeast Flocculation Activity in Malt. JOURNAL OF THE AMERICAN SOCIETY OF BREWING CHEMISTS 2018. [DOI: 10.1094/asbcj-63-0147] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Koizumi H, Kato Y, Ogawa T. Structural Features of Barley Malt Polysaccharides Inducing Premature Yeast Flocculation. JOURNAL OF THE AMERICAN SOCIETY OF BREWING CHEMISTS 2018. [DOI: 10.1094/asbcj-2009-0422-01] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Koizumi H, Kato Y, Ogawa T. Barley Malt Polysaccharides Inducing Premature Yeast Flocculation and Their Possible Mechanism. JOURNAL OF THE AMERICAN SOCIETY OF BREWING CHEMISTS 2018. [DOI: 10.1094/asbcj-2008-0614-01] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Yamamoto R, Suzuki S, Sugawara R, isito J, Koizumi H, Momoo T, Tanaka F. Abstract WP328: Suppression of Tachycardia and Cost Effectiveness of Bisoprolol Transdermal Patch Addition to Intravenous Nicardipine in Antihypertensive Treatment for Acute Intracerebral Hemorrhage. Stroke 2018. [DOI: 10.1161/str.49.suppl_1.wp328] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Introduction:
In patients with hypertensive intracerebral hemorrhage (ICH), intravenous (i.v.) Nicardipine is often used to lower the blood pressure. However, reflex tachycardia is a well-known side effect. Bisoprolol transdermal patch, a beta-blocker to be percutaneously absorbed, recently became commercially available in Japan. It can be used for patients with acute ICH with vomiting or dysphagia. The aim of this study is to evaluate suppressing effect of tachycardia and cost effectiveness of adding Bisoprolol transdermal patch to i.v. Nicardipine in patients with hypertensive ICH.
Methods:
We randomly assigned patients who were admitted to our department from January 2015 through April 2017 because of acute ICH to single antihypertensive treatment group (i.v. Nicardipine only) or combination treatment group (Bisoprolol transdermal patch and i.v. Nicardipine). The primary outcome was heart rate during 24 hours after admission. Key secondary outcomes were dose of Nicardipine (drug costs), neurological prognosis as defined by modified Rankin scale 0 to 2, and adverse drug reactions.
Results:
A total of 59 patients were randomized into two groups; 35 patients were assigned to single antihypertensive treatment group and 24 patients were assigned to combination treatment group. There were no significant differences between two groups in baseline characteristics on admission (age, body weight, hematoma volume, NIHSS, systolic blood pressure, heart rate). Mean heart rate during 24 hours after admission were significantly lower in combination treatment group (78.10±11.43 vs. 86.13±12.46, P=0.021). Hourly heart rate of combination treatment group was significantly lower in 5 to 24 hours later from start of treatment. Dose of Nicardipine was tended to be lower in combination treatment group (80.54±65.93 vs. 119.7±96.80mg, P=0.10), and costs of antihypertensive drug was tended to be lower in combination treatment group (5708±4569 vs. 8292±6708 yen, P=0.13). Neurological prognosis showed no difference (P=0.72), and bradycardia occurred in three patients of combination treatment group.
Conclusions:
Adding Bisoprolol transdermal patch to Nicardipine can decrease heart rate and may reduce drug costs in antihypertensive treatment for acute ICH.
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Koizumi H, Hoshi K, Yamamoto D, Asari Y, Kumabe T. Relationship between Stroke Events during Pachinko Play and Prognosis. J Stroke Cerebrovasc Dis 2017; 26:2971-2975. [PMID: 28939050 DOI: 10.1016/j.jstrokecerebrovasdis.2017.07.022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2017] [Revised: 07/08/2017] [Accepted: 07/23/2017] [Indexed: 10/18/2022] Open
Abstract
BACKGROUND This study investigated whether pachinko play influences the outcome of stroke events, and identified the significant variables affecting outcomes. METHODS We reviewed the medical and imaging records of 2075 consecutive patients with stroke from January 2003 through June 2012. The remaining patients were divided into 2 groups, the pachinko players group (PP) and the non-pachinko players group (NPP). Background factors were recorded on admission. Multivariate logistic regression analysis was used to identify the factors significantly correlated with Glasgow Outcome Scale (GOS) score and risk of death at the time of discharge. RESULTS The PP group exhibited higher prevalence of hypertension and current smoking compared with the NPP group. However, no difference was found in outcomes between the PP and NPP groups. Multivariate analysis identified the dependent predictive variables for GOS as age (adjusted β = -.18, 95% confidence interval [CI]: -.22 to -.14, P <.001), Glasgow Coma Scale (GCS) score on admission (adjusted β = .64, 95% CI: .60 to .68, P <.001), and history of hypertension (adjusted β = -.06, 95% CI: -.10 to -.02, P = .007). Logistic regression analysis showed that age (odds ratio = 1.02, 95% CI: 1.01 to 1.04, P <.001) and GCS score on admission (odds ratio = .72, 95% CI: .69 to .75, P <.001) were significantly associated with death at the time of discharge. CONCLUSIONS Patients with stroke during playing pachinko have higher prevalence of hypertension and higher smoking rate, but pachinko play itself was not a critical factor determining the outcome of patients with stroke in our emergency center.
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Sato S, Kawamura S, Ando M, Nakamura T, Tsubono K, Araya A, Funaki I, Ioka K, Kanda N, Moriwaki S, Musha M, Nakazawa K, Numata K, Sakai SI, Seto N, Takashima T, Tanaka T, Agatsuma K, Aoyanagi KS, Arai K, Asada H, Aso Y, Chiba T, Ebisuzaki T, Ejiri Y, Enoki M, Eriguchi Y, Fujimoto MK, Fujita R, Fukushima M, Futamase T, Ganzu K, Harada T, Hashimoto T, Hayama K, Hikida W, Himemoto Y, Hirabayashi H, Hiramatsu T, Hong FL, Horisawa H, Hosokawa M, Ichiki K, Ikegami T, Inoue KT, Ishidoshiro K, Ishihara H, Ishikawa T, Ishizaki H, Ito H, Itoh Y, Kawashima N, Kawazoe F, Kishimoto N, Kiuchi K, Kobayashi S, Kohri K, Koizumi H, Kojima Y, Kokeyama K, Kokuyama W, Kotake K, Kozai Y, Kudoh H, Kunimori H, Kuninaka H, Kuroda K, Maeda KI, Matsuhara H, Mino Y, Miyakawa O, Miyoki S, Morimoto MY, Morioka T, Morisawa T, Mukohyama S, Nagano S, Naito I, Nakamura K, Nakano H, Nakao K, Nakasuka S, Nakayama Y, Nishida E, Nishiyama K, Nishizawa A, Niwa Y, Noumi T, Obuchi Y, Ohashi M, Ohishi N, Ohkawa M, Okada N, Onozato K, Oohara K, Sago N, Saijo M, Sakagami M, Sakata S, Sasaki M, Sato T, Shibata M, Shinkai H, Somiya K, Sotani H, Sugiyama N, Suwa Y, Suzuki R, Tagoshi H, Takahashi F, Takahashi K, Takahashi K, Takahashi R, Takahashi R, Takahashi T, Takahashi H, Akiteru T, Takano T, Taniguchi K, Taruya A, Tashiro H, Torii Y, Toyoshima M, Tsujikawa S, Tsunesada Y, Ueda A, Ueda KI, Utashima M, Wakabayashi Y, Yamakawa H, Yamamoto K, Yamazaki T, Yokoyama J, Yoo CM, Yoshida S, Yoshino T. The status of DECIGO. ACTA ACUST UNITED AC 2017. [DOI: 10.1088/1742-6596/840/1/012010] [Citation(s) in RCA: 102] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Koizumi H, Fujioka H, Togashi K, Thompson J, Yates JR, Gleeson JG, Emoto K. DCLK1 phosphorylates the microtubule-associated protein MAP7D1 to promote axon elongation in cortical neurons. Dev Neurobiol 2017; 77:493-510. [PMID: 27503845 DOI: 10.1002/dneu.22428] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2016] [Revised: 08/03/2016] [Accepted: 08/05/2016] [Indexed: 12/14/2022]
Abstract
Doublecortin-like kinase 1 (DCLK1) is a member of the neuronal microtubule-associated doublecortin (DCX) family and functions in multiple stages of neural development including radial migration and axon growth of cortical neurons. DCLK1 is suggested to play the roles in part through its protein kinase activity, yet the kinase substrates of DCLK1 remain largely unknown. Here we have identified MAP7D1 (microtubule-associated protein 7 domain containing 1) as a novel substrate of DCLK1 by using proteomic analysis. MAP7D1 is expressed in developing cortical neurons, and knockdown of MAP7D1 in layer 2/3 cortical neurons results in a significant impairment of callosal axon elongation, but not of radial migration, in corticogenesis. We have further defined the serine 315 (Ser 315) of MAP7D1 as a DCLK1-induced phosphorylation site and shown that overexpression of a phosphomimetic MAP7D1 mutant in which Ser 315 is substituted with glutamic acid (MAP7D1 S315E), but not wild-type MAP7D1, fully rescues the axon elongation defects in Dclk1 knockdown neurons. These data demonstrate that DCLK1 phosphorylates MAP7D1 on Ser 315 to facilitate axon elongation of cortical neurons. © 2016 Wiley Periodicals, Inc. Develop Neurobiol 77: 419-437, 2017.
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Koizumi H, Nomura K, Ishihama K, Yamanishi T, Enomoto A, Kogo M. Inhibition of Trigeminal Respiratory Activity by Suckling. J Dent Res 2016; 86:1073-7. [DOI: 10.1177/154405910708601110] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
The trigeminal motor system is involved in many rhythmic oral-motor behaviors, such as suckling, mastication, swallowing, and breathing. Despite the obvious importance of functional coordination among these rhythmic activities, the system is not well-understood. In the present study, we examined the hypothesis that an interaction between suckling and breathing exists in the brainstem, by studying the respiratory activity in trigeminal motoneurons (TMNs) during fictive suckling using a neonatal rat in vitro brainstem preparation. The results showed that fictive suckling, which was neurochemically induced by bath application of N-methyl-D,L-aspartate and bicuculline-methiodide, or by local micro-injection of the same drugs to the trigeminal motor nucleus, inhibited the inspiratory activities in both respiration TMNs and respiratory rhythm-generating neurons. Under patch-clamp recording, fictive suckling caused membrane potential hyperpolarization of respiration TMNs. We conclude that the brainstem preparation contains an inhibitory circuit for respiratory activity in the trigeminal motor system via the rhythm-generating network for suckling. Abbreviations: BIC, bicuculline methiodide; GABA, gamma aminobutyric acid; NMA, N-methyl-D,L-aspartate; NMDA, N-methyl-D-aspartate; and TMN, trigeminal motoneuron.
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Koizumi H, Kawaguchi R, Ohkubo JI, Ikezaki S, Kitamura T, Hohchi N, Hashida K, Suzuki H. Expressions of isopeptide bonds and corneodesmosin in middle ear cholesteatoma. Clin Otolaryngol 2016; 42:252-262. [PMID: 27390311 DOI: 10.1111/coa.12703] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/02/2016] [Indexed: 01/23/2023]
Abstract
OBJECTIVE Isopeptide bonds form cross-links between constituent proteins in the horny layer of the epidermis. Corneodesmosin (CDSN) is a major component of corneodesmosomes, which bind corneocytes together. Both play important roles in maintaining epidermal barrier functions. In the present study, we investigated the expressions of isopeptide bonds, CDSN, and related enzymes in middle ear cholesteatoma in comparison with the skin. DESIGN Prospective case series of patients with middle ear cholesteatoma. SETTING Tertiary medical institute. PARTICIPANTS Cholesteatoma and normal postauricular skin were collected from patients with acquired middle ear cholesteatoma during tympanomastoidectomy. MAIN OUTCOME MEASURES Expression of e-(g-glutamyl)lysine isopeptide bonds was examined by immunohistochemistry; Expressions of transglutaminase (TGase)1, TGase2, TGase3, and TGase5 by immunohistochemistry and quantitative RT-PCR (qRT-PCR); expression of CDSN by immunohistochemistry, qRT-PCR, and Western blot; and expressions of tissue kallikrein-related peptidase (KLK)5, KLK7, KLK14, and serine peptidase inhibitor Kazal type 5 (SPINK5) by qRT-PCR. RESULTS TGase2 was higher (P=0.0046) and TGase5 was lower (P=0.0008) in cholesteatoma than in the postauricular skin. Immunoreactivity for isopeptide bonds was localized in the granular and horny layers, and was not different between the two tissues. Immunoreactivity for CDSN was localized in the granular layer, and was lower in cholesteatoma than in the skin (P=0.0090). Western blot and qRT-PCR confirmed that the expression of CDSN was lower in cholesteatoma than in the skin. Expressions of KLK5, KLK7, KLK14, or SPINK5 were not different between the two tissues. CONCLUSIONS These results indicate that the production of CDSN is likely to be suppressed in cholesteatoma, which would account, at least in part, for the mechanical fragility and increased permeability of the cholesteatoma epithelium.
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Watanabe M, Nomura G, Hirata M, Imai K, Koizumi H. Studies on the validity of urinary enzyme assay in the diagnosis of drug-induced renal lesions in rats. Toxicol Pathol 2016. [DOI: 10.1177/019262338000800202] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The validity of urinary enzyme assays in the diagnosis of renal lesions was studied in rats for evaluation in comparison with other tests such as urinalysis and serum biochemical assay. Tubular damages of slight or severe degree were induced by daily intramuscular administration of 500 mg/kg or 1,000 mg/kg of kanamycin (KM) for 7 and 6 days respectively. Glomerular lesions were induced subcutaneous injection of 30 mg/kg of puromycin (PM) for 6 days. The enzymes, assayed daily before and after the onset of administration, were lactic dehydrogenase (LDH), aspartate aminotransferase (GOT), alkaline phosphatase (AI-P), acid phosphatase (Ac-P), leucin aminopeptidase (LAP) and γ-glutamyl transpeptidase (γ-GT). The distribution of these enzymic activities in the kidneys was histochemically examined. Assays of LDH and GOT on the kidney tissue homogenate were also conducted. Histological alterations of the kidneys were examined in the rats sacrificed after termination of administration. Significant elevation of the LDH and GOT urine levels were observed within 24 hours in rats treated with 500 mg/kg of KM with the high enzyme levels being maintained throughout the administration period, while the other enzymes remained within pretreatment levels or were only slightly elevated. Serum urea nitrogen (BUN) and creatinine levels remained unchanged with no abnormality being found in the urinalysis of this group. In the group treated with 1,000 mg/ kg of KM, concomitant rising of all urine enzyme levels was observed, with elevation of the LDH and GOT levels being extreme while the BUN and serum creatinine levels rose only at the termination of the administration period. The BUN level rose earlier than did most of the urinary enzymes in puromycin-treated rats. Depletion of LDH activity was histochemically demonstrated in the kidneys where no histological alteration was observable, while the activities of AI-P, γ-GT, and LAP showed no distinct changes until the tabular destruction became severe. Upon termination of both KM and PM administration, the depletion of LDH and GOT activities was noted in a kidney homogenate assay for the enzymes. These results clearly showed that among the enzymes studied, the LDH and GOT urine levels are the most sensitive indicators for detecting proximal tubular lesions induced by KM. It was further demonstrated that the urinary enzyme assay in combination with serum BUN measurement is an effective examination for distinguishing tubular from glomerular lesions.
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Shimizu S, Mochizuki T, Osawa S, Sekiguchi T, Koizumi H, Kumabe T. [Extendable Cords to Prevent Tumbling of a Suction Device during Craniotomy]. NO SHINKEI GEKA. NEUROLOGICAL SURGERY 2016; 44:111-3. [PMID: 26856263 DOI: 10.11477/mf.1436203240] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
OBJECTIVE Suction is necessary during craniotomy, and intraoperative tumbling of the suction device interrupts operative procedures. To avoid this, we developed a technique that would fasten the device to an extendable cord as is used to secure cell phones. SURGICAL TECHNIQUE We used this technique in more than 300 craniotomies at the specific point of time when the suction device tends to tumble, i. e., during the opening and closure of a wound, which requires frequent instrument exchanges. Extendable cords fastened to the tip of the suction hose using a gift tie were attached to the drapes to secure the suction device next to the operative field. During the operation, the extendable cord followed the suction device manipulations. Consequently, although there was some tension in the cord during its extension, the maneuverability of the suction device was maintained. As the hanging suction device was closer to the operative field than devices stored in conventional pockets, its manipulation was easier and quicker. Upon release, the suction device automatically returned to its original position without distracting the surgeon. Tumbling of the device was prevented, and there were no procedure-related complications. CONCLUSIONS Our simple modification using extendable cords prevented tumbling, avoided unnecessary replacements, and eased the manipulation of a suction device.
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Koizumi H, Suzuki H, Ohbuchi T, Kitamura T, Hashida K, Nakamura M. Increased permeability of the epithelium of middle ear cholesteatoma. Clin Otolaryngol 2016; 40:106-14. [PMID: 25319490 DOI: 10.1111/coa.12332] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/05/2014] [Indexed: 12/23/2022]
Abstract
OBJECTIVE We investigated the electrical impedance of and the expressions of tight junction molecules in the cholesteatoma epithelium to provide supporting evidence for the acid lysis theory of bone resorption in middle ear cholesteatoma. METHODS Study subjects were patients with primary acquired middle ear cholesteatoma and those with non-cholesteatomatous chronic otitis media who underwent tympanomastoidectomy. The electrical impedance of the cholesteatoma epithelium was measured during tympanomastoidectomy by loading alternating currents of 320 Hz and 30.7 kHz. The expressions of tricellulin (MARVELD2), claudin-1 (CLDN1) and claudin-3 (CLDN3) were examined by fluorescence immunohistochemistry and quantitative reverse transcription-polymerase chain reaction. RESULTS The electrical impedance of the cholesteatoma epithelium was significantly lower than that of the post-auricular skin and external auditory canal skin at both 320 Hz and 30.7 kHz. Immunoreactivity for MARVELD2, CLDN1 and CLDN3 was localised mainly in the granular layer, and to lesser degree, in the horny and spinous layers in both the cholesteatoma tissue and post-auricular skin. Fluorescence intensity was moderate for MARVELD2, weak for CLDN1 and strong for CLDN3. The expressions of MARVELD2, CLDN1 and CLDN3 mRNA were significantly lower in the cholesteatoma tissue than in the post-auricular skin. CONCLUSIONS These results indicate the increased permeability of the cholesteatoma epithelium and suggest that this change is, at least partially, dependent on the decrease in the expressions of the tight junction molecules. This evidence supports the acid lysis hypothesis of bone resorption in cholesteatoma.
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Yasunaga KI, Tezuka A, Ishikawa N, Dairyo Y, Togashi K, Koizumi H, Emoto K. Adult Drosophila sensory neurons specify dendritic territories independently of dendritic contacts through the Wnt5-Drl signaling pathway. Genes Dev 2015; 29:1763-75. [PMID: 26302791 PMCID: PMC4561484 DOI: 10.1101/gad.262592.115] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Here, Yasunaga et al. use Drosophila class IV dendrite arborization (C4da) sensory neurons as a system to investigate how neurons specify dendritic territories during neuronal development. They show that, unlike the larval dendrites, adult C4da dendrites define the dendritic boundary independently of dendritic contacts and that Wnt5 derived from sternites is required for specification of the ventral boundaries of C4da dendrites. These findings provide novel insights into how dendritic territories of neurons develop and the role of the Wnt5–Drl signaling pathway in the contact-independent dendritic boundary specification. Sensory neurons with common functions are often nonrandomly arranged and form dendritic territories in stereotypic spatial patterns throughout the nervous system, yet molecular mechanisms of how neurons specify dendritic territories remain largely unknown. In Drosophila larvae, dendrites of class IV sensory (C4da) neurons completely but nonredundantly cover the whole epidermis, and the boundaries of these tiled dendritic fields are specified through repulsive interactions between homotypic dendrites. Here we report that, unlike the larval C4da neurons, adult C4da neurons rely on both dendritic repulsive interactions and external positional cues to delimit the boundaries of their dendritic fields. We identify Wnt5 derived from sternites, the ventral-most part of the adult abdominal epidermis, as the critical determinant for the ventral boundaries. Further genetic data indicate that Wnt5 promotes dendrite termination on the periphery of sternites through the Ryk receptor family kinase Derailed (Drl) and the Rho GTPase guanine nucleotide exchange factor Trio in C4da neurons. Our findings thus uncover the dendritic contact-independent mechanism that is required for dendritic boundary specification and suggest that combinatory actions of the dendritic contact-dependent and -independent mechanisms may ensure appropriate dendritic territories of a given neuron.
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Koizumi H, Uda S, Fujiwara K, Tachibana M, Kojima K, Nozawa J. Crystallization of high-quality protein crystals using an external electric field. J Appl Crystallogr 2015. [DOI: 10.1107/s1600576715015885] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
The effect of a 20 kHz external electric field on the quality of tetragonal hen egg white (HEW) lysozyme crystals was investigated using X-ray diffraction rocking-curve measurements. The full width at half-maximum was found to be larger for high-order reflections but smaller for low-order reflections. In particular, it was revealed that a large amount of local strain is accumulated in tetragonal HEW lysozyme crystals grown under an applied field at 20 kHz. Comparison with previous results obtained for crystals grown with an applied field at 1 MHz [Koizumi, Uda, Fujiwara, Tachibana, Kojima & Nozawa (2013).J. Appl. Cryst.46, 25–29] indicated that improvement of the protein crystal quality could be achieved by selection of an appropriate frequency for the applied electric field, which has a significant effect on the growth of the solid.
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Kuwabara K, Higuchi Y, Ogasawara T, Koizumi H, Haga T. Wearable blood flowmeter appcessory with low-power laser Doppler signal processing for daily-life healthcare monitoring. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2015; 2014:6274-7. [PMID: 25571431 DOI: 10.1109/embc.2014.6945063] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
A new appcessory for monitoring peripheral blood flow in daily life consists of a wearable laser Doppler sensor device and a cooperating smart phone application. Bluetooth Low Energy connects them wirelessly. The sensor device features ultralight weight of 15 g and an intermittent signal processing technique that reduces power consumption to only 7 mW at measurement intervals of 0.1 s. These features enable more than 24-h continuous monitoring of peripheral blood flow in daily life, which can provide valuable vital-sign information for healthcare services.
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Kanamori T, Togashi K, Koizumi H, Emoto K. Dendritic Remodeling. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2015; 318:1-25. [DOI: 10.1016/bs.ircmb.2015.05.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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Kitajima N, Tsukashima S, Fujii D, Tachibana M, Koizumi H, Wako K, Kojima K. Elastic constants in orthorhombic hen egg-white lysozyme crystals. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2014; 89:012714. [PMID: 24580264 DOI: 10.1103/physreve.89.012714] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2013] [Indexed: 06/03/2023]
Abstract
The ultrasonic sound velocities of cross-linked orthorhombic hen egg-white lysozyme (HEWL) crystals, including a large amount of water in the crystal, were measured using an ultrasonic pulse-echo method. As a result, seven elastic constants of orthorhombic crystals were observed to be C11 = 5.24 GPa, C22 = 4.87 GPa, C12 = 4.02 GPa, C33 = 5.23 GPa, C44 = 0.30 GPa, C55 = 0.40 GPa, and C66 = 0.43 GPa, respectively. However, C13 and C23 could not be observed because the suitable crystal planes could not be cut from bulk crystals. We conclude that the observed elastic constants of the cross-linked crystals are coincident with those of the intrinsic crystals without cross-linking. Moreover, the characteristics of the elastic constants in orthorhombic HEWL crystals are due to the fact that the shear elastic constants, C44, C55, and C66, are softer than in tetragonal crystals. That is, the shear components, C44, C55, and C66, are one half of those of the tetragonal crystals.
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Shin E, Kashiwagi Y, Kuriu T, Iwasaki H, Tanaka T, Koizumi H, Gleeson JG, Okabe S. Doublecortin-like kinase enhances dendritic remodelling and negatively regulates synapse maturation. Nat Commun 2013; 4:1440. [PMID: 23385585 PMCID: PMC4017031 DOI: 10.1038/ncomms2443] [Citation(s) in RCA: 71] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2012] [Accepted: 01/03/2013] [Indexed: 11/09/2022] Open
Abstract
Dendritic morphogenesis and formation of synapses at appropriate dendritic locations are essential for the establishment of proper neuronal connectivity. Recent imaging studies provide evidence for stabilization of dynamic distal branches of dendrites by the addition of new synapses. However, molecules involved in both dendritic growth and suppression of synapse maturation remain to be identified. Here we report two distinct functions of doublecortin-like kinases, chimeric proteins containing both a microtubule-binding domain and a kinase domain in postmitotic neurons. First, doublecortin-like kinases localize to the distal dendrites and promote their growth by enhancing microtubule bundling. Second, doublecortin-like kinases suppress maturation of synapses through multiple pathways, including reduction of PSD-95 by the kinase domain and suppression of spine structural maturation by the microtubule-binding domain. Thus, doublecortin-like kinases are critical regulators of dendritic development by means of their specific targeting to the distal dendrites, and their local control of dendritic growth and synapse maturation.
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Yoneda H, Nakamura T, Shirao S, Tanaka N, Ishihara H, Suehiro E, Koizumi H, Isotani E, Suzuki M. Multicenter Prospective Cohort Study on Volume Management After Subarachnoid Hemorrhage: Hemodynamic Changes According to Severity of Subarachnoid Hemorrhage and Cerebral Vasospasm. Stroke 2013; 44:2155-61. [DOI: 10.1161/strokeaha.113.001015] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Shimizu S, Kondo K, Yamazaki T, Koizumi H, Miyazaki T, Osawa S, Sagiuchi T, Nakayama K, Yamamoto I, Fujii K. Hanging foot switch for bipolar forceps: a device for surgeons operating in the standing position: technical note. Neurol Med Chir (Tokyo) 2013; 53:53-5. [PMID: 23358172 DOI: 10.2176/nmc.53.53] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
For surgeons operating in the standing position, the manipulation of foot switches involves shifting of the weight to the pivoting leg and the possible loss of contact between the switch and the foot. We solved this problem by changing the position of the switch that operates bipolar forceps. Our novel device is made of aluminum plates. The base plate features a foot strap and a height-adjustable overhang over the switch-operating foot. A commercially-available disc type foot switch is attached to the underside of the overhang in upside-down position, so the switch is operable with the toe. To turn on the switch, the toe is flexed dorsally to push the switch pedal, so the action is limited to the part distal to the metatarsophalangeal joints. Our switch was used in more than 100 consecutive microsurgeries performed by surgeons operating in the standing position. The switch manipulation required no shifting of the weight and was easier and quicker than manipulation of conventionally-placed switches. The surgeons were able to change the foot position freely with the modified switch, thereby avoiding loss of contact with the switch. The modified switch placement reduced physical fatigue in the lower extremities, annoyance related to the manipulation of conventionally-placed switches, and increased the comfort of surgeons operating in the standing position.
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Koizumi H, Uda S, Fujiwara K, Tachibana M, Kojima K, Nozawa J. Improvement of crystal quality for tetragonal hen egg white lysozyme crystals under application of an external alternating current electric field. J Appl Crystallogr 2013. [DOI: 10.1107/s0021889812048716] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
X-ray diffraction rocking-curve measurements were performed on tetragonal hen egg white lysozyme (HEWL) crystals grown with and without application of an external alternating current (AC) electric field, and then the crystal quality was assessed by the FWHMs of each rocking-curve profile. The FWHMs for HEWL crystals grown with an external electric field were smaller than those for crystals grown without. In particular, the average FWHM for the 12 12 0 reflection with an external electric field (0.0034°) was significantly smaller than that without (0.0061°). This indicates that the crystal quality of HEWL crystals was improved by application of the external AC electric field. This crystallization technique can be expected to enhance the resolution of protein molecule structure analysis by X-ray diffraction.
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Ise T, Tsukizaki R, Togo H, Koizumi H, Kuninaka H. Electric field measurement in microwave discharge ion thruster with electro-optic probe. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2012; 83:124702. [PMID: 23278009 DOI: 10.1063/1.4770116] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
In order to understand the internal phenomena in a microwave discharge ion thruster, it is important to measure the distribution of the microwave electric field inside the discharge chamber, which is directly related to the plasma production. In this study, we proposed a novel method of measuring a microwave electric field with an electro-optic (EO) probe based on the Pockels effect. The probe, including a cooling system, contains no metal and can be accessed in the discharge chamber with less disruption to the microwave distribution. This method enables measurement of the electric field profile under ion beam acceleration. We first verified the measurement with the EO probe by a comparison with a finite-difference time domain numerical simulation of the microwave electric field in atmosphere. Second, we showed that the deviations of the reflected microwave power and the beam current were less than 8% due to inserting the EO probe into the ion thruster under ion beam acceleration. Finally, we successfully demonstrated the measurement of the electric-field profile in the ion thruster under ion beam acceleration. These measurements show that the electric field distribution in the thruster dramatically changes in the ion thruster under ion beam acceleration as the propellant mass flow rate increases. These results indicate that this new method using an EO probe can provide a useful guide for improving the propulsion of microwave discharge ion thrusters.
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Tomita Y, Koizumi H, Uda S, Fujiwara K, Nozawa J. Control of Gibbs free energy relationship between hen egg white lysozyme polymorphs under application of an external alternating current electric field. J Appl Crystallogr 2012. [DOI: 10.1107/s002188981200249x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
The distribution of phases between bulk (tetragonal structure) and spherulitic crystals for hen egg white lysozyme was controlled under application of an external alternating current electric field. The distribution of phases differed depending on differences in the magnitude of the electrostatic energy contribution to the respective chemical potentials of the two solid phases. Therefore, the Gibbs free energy relationship between the two solid phases could be controlled by changing the frequency of the applied external electric field. Such a method of controlling the Gibbs free energy relationship among polymorphs would be adaptable to many kinds of protein.
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Okita S, Morigaki R, Koizumi H, Kaji R, Nagahiro S, Goto S. Cell type-specific localization of optineurin in the striatal neurons of mice: implications for neuronal vulnerability in Huntington's disease. Neuroscience 2011; 202:363-70. [PMID: 22155493 DOI: 10.1016/j.neuroscience.2011.11.059] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2011] [Revised: 11/21/2011] [Accepted: 11/24/2011] [Indexed: 11/26/2022]
Abstract
Striatal neuropathology of Huntington's disease (HD) involves primary and progressive degeneration of the medium-sized projection neurons, with relative sparing of the local circuit interneurons. The mechanism for such a patterned cell loss in the HD striatum continues to remain unclear. Optineurin (OPTN) is one of the proteins interacting with huntingtin and plays a protective role in several neurodegenerative disorders. To determine the cellular localization pattern of OPTN in the mouse striatum, we employed a highly sensitive immunohistochemistry with the tyramide signal amplification system. In this study, we show that OPTN appeared as a cytoplasmic protein within the subsets of the striatal neurons. Of particular interest was that OPTN was abundantly expressed in the interneurons, whereas low levels of OPTN were observed in the medium projection neurons. This cell type-specific distribution of OPTN in the striatum is strikingly complementary to the pattern of neuronal loss typically observed in the striatum of patients with HD. We suggest that OPTN abundance is an important cellular factor in considering the cell type-specific vulnerability of striatal neurons in HD.
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