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1.  Assessment of visual space recognition of patients with unilateral spatial neglect and visual field defects using a head mounted display system 
[Purpose] The purpose of this study was the development of a method for presenting diverse visual information and assessing visual space recognition using a new head mounted display (HMD) system. [Subjects] Eight patients: four with unilateral spatial neglect (USN) and four with visual field defects (VFD). [Methods] A test sheet was placed on a desk, and its image was projected on the display of the HMD. Then, space recognition assessment was conducted using a cancellation test and motion analysis of the eyeballs and head under four conditions with images reduced in size and shifted. [Results] Leftward visual search was dominant in VFD patients, while rightward visual search was dominant in USN patients. The angular velocity of leftward eye movement during visual search of the right sheet decreased in both patient types. Motion analysis revealed a tendency of VFD patients to rotate the head in the affected direction under the left reduction condition, whereas USN patients rotated it in the opposite direction of the neglect. [Conclusion] A new HMD system was developed for presenting diverse visual information and assessing visual space recognition which identified the differences in the disturbance of visual space recognition of VFD and USN patients were indicated.
PMCID: PMC4792969  PMID: 27065515
Unilateral spatial neglect; Visual field defects; Visual space recognition
2.  The Possible Mechanism of Idiosyncratic Lapatinib-Induced Liver Injury in Patients Carrying Human Leukocyte Antigen-DRB1*07:01 
PLoS ONE  2015;10(6):e0130928.
Idiosyncratic lapatinib-induced liver injury has been reported to be associated with human leukocyte antigen (HLA)-DRB1*07:01. In order to investigate its mechanism, interaction of lapatinib with HLA-DRB1*07:01 and its ligand peptide derived from tetanus toxoid, has been evaluated in vitro. Here we show that lapatinib enhances binding of the ligand peptide to HLA-DRB1*07:01. Furthermore in silico molecular dynamics analysis revealed that lapatinib could change the β chain helix in the HLA-DRB1*07:01 specifically to form a tightly closed binding groove structure and modify a large part of the binding groove. These results indicate that lapatinib affects the ligand binding to HLA-DRB1*07:01 and idiosyncratic lapatinib-induced liver injury might be triggered by this mechanism. This is the first report showing that the clinically available drug can enhance the binding of ligand peptide to HLA class II molecules in vitro and in silico.
PMCID: PMC4476721  PMID: 26098642
3.  Identification of activating enzymes of a novel FBPase inhibitor prodrug, CS-917 
CS-917 (MB06322) is a selective small compound inhibitor of fructose 1,6-bisphosphatase (FBPase), which is expected to be a novel drug for the treatment of type 2 diabetes by inhibiting gluconeogenesis. CS-917 is a bisamidate prodrug and activation of CS-917 requires a two-step enzyme catalyzed reaction. The first-step enzyme, esterase, catalyzes the conversion of CS-917 into the intermediate form (R-134450) and the second-step enzyme, phosphoramidase, catalyzes the conversion of R-134450 into the active form (R-125338). In this study, we biochemically purified the CS-917 esterase activity in monkey small intestine and liver. We identified cathepsin A (CTSA) and elastase 3B (ELA3B) as CS-917 esterases in the small intestine by mass spectrometry, whereas we found CTSA and carboxylesterase 1 (CES1) in monkey liver. We also purified R-134450 phosphoramidase activity in monkey liver and identified sphingomyelin phosphodiesterase, acid-like 3A (SMPADL3A), as an R-134450 phosphoramidase, which has not been reported to have any enzyme activity. Recombinant human CTSA, ELA3B, and CES1 showed CS-917 esterase activity and recombinant human SMPDL3A showed R-134450 phosphoramidase activity, which confirmed the identification of those enzymes. Identification of metabolic enzymes responsible for the activation process is the requisite first step to understanding the activation process, pharmacodynamics and pharmacokinetics of CS-917 at the molecular level. This is the first identification of a phosphoramidase other than histidine triad nucleotide-binding protein (HINT) family enzymes and SMPDL3A might generally contribute to activation of the other bisamidate prodrugs.
PMCID: PMC4492754  PMID: 26171222
Biochemical purification; bisamidate prodrug; CS-917; drug metabolizing enzyme; FBPase inhibitor; phosphoramidase
4.  Results and Current Trends of Multimodality Treatment for Infectious Intracranial Aneurysms 
Neurologia Medico-Chirurgica  2015;55(2):155-162.
The authors retrospectively reviewed their cases of infectious intracranial aneurysms and discuss results and trends of current treatment modalities including medical, neurosurgical, and endovascular. Twenty patients (10 males and 10 females; mean age 46 years) with 23 infectious aneurysms were treated by various treatment modalities during a 15-year period. Fifteen cases (75.0%) were caused by infective endocarditis. Eleven aneurysms (47.8%) were ruptured. Two aneurysms (8.7%) presented a mass effect and 7 (30.4%) were unruptured and asymptomatic. The average aneurysm size was 6.5 ± 4.8 mm (range 1–22 mm). The aneurysms were located in proximal cerebral circulation in 7 (30.4%) and distal in 16 (69.6%). Six (26.1%) aneurysms were treated surgically (5: trapping, 1: neck clipping), 10 (43.5%) endovascularly (7: trapping, 2: proximal occlusion, 1: saccular coiling), and the remaining 7 (30.4%) medically. Endovascular treatment was gradually increased with time. Medical and surgical treatments were continuously performed during the study period. Surgery was preferred for the patient with intraparenchymal hematoma or treated by bypass surgery. Three periprocedural minor complications occurred in endovascular treatment. There was one postoperative infarction with permanent deficit developed from surgical treatment. During the follow-up period (mean 28.8 months), none of the aneurysms presented a recurrence or rebleeding. Thirteen patients (65.0%) had favorable clinical outcomes (modified Rankin Scale: 0–2), although four (20.0%) had poor outcomes (modified Rankin Score: 5–6). A multimodal approach for the management of infectious aneurysms achieved satisfactory results. Endovascular intervention is a feasible and efficacious treatment option and surgical intervention is still an indispensable procedure.
PMCID: PMC4533411  PMID: 25746310
infectious aneurysm; intracranial; surgery; endovascular treatment; medical treatment
5.  Spinal Cord Infarction Is an Unusual Complication of Intracranial Neuroendovascular Intervention 
Interventional Neuroradiology  null;19(4):500-505.
Spinal cord infarction is an unusual complication of intracranial neuroendovascular intervention. The authors report on two cases involving spinal cord infarction after endovascular coil embolization for large basilar-tip aneurysms. Each aneurysm was sufficiently embolized by the stent/balloon combination-assisted technique or double catheter technique. However, postoperatively, patients presented neurological symptoms without cranial nerve manifestation. MRI revealed multiple infarctions at the cervical spinal cord. In both cases, larger-sized guiding catheters were used for an adjunctive technique. Therefore, guiding catheters had been wedged in the vertebral artery (VA). The wedge of the VA and flow restriction may have caused thromboemboli and/or hemodynamic insufficiency of the spinal branches from the VA (radiculomedullary artery), resulting in spinal cord infarction. Spinal cord infarction should be taken into consideration as a complication of endovascular intervention for lesions of the posterior circulation.
PMCID: PMC3902752  PMID: 24355157
spinal cord infarction; intracranial aneurysm; neuroendovascular intervention; complication
6.  Stent/Balloon Combination Assist Technique for Wide-Necked Basilar Terminal Aneurysms 
Interventional Neuroradiology  2013;19(3):299-305.
We describe an enhanced endovascular procedure for the coiling of broad-necked basilar terminal aneurysms with a combined balloon/stent assist technique. A balloon-assisted catheter is inserted in the origin of one posterior cerebral artery (PCA) and an assisted stent is deployed from the opposite PCA to the basilar artery. A microcatheter for coiling is inserted through the stent strut (trans-cell approach), and the aneurysm is coiled under stent support and assisted balloon inflation to keep the patency of both PCAs. This technique is more beneficial for reducing the risk of stent deformity than Y-stenting, and it provides a simpler procedure than other advanced stent techniques. Additionally, it enables an easy approach when retreatment is necessary for aneurysm recurrence. This technique may be one of the useful procedures for embolizing broad-necked basilar terminal aneurysms safely and effectively.
PMCID: PMC3806004  PMID: 24070078
intracranial aneurysm, embolization, stent, balloon
7.  Angioplasty and Stenting for Intracranial Stenosis 
Neurologia Medico-Chirurgica  2013;54(1):46-53.
Of the patients enrolled in the Japanese Registry of Neuroendovascular Therapy (JR-NET), a surveillance study in Japanese, 1133 patients who underwent intracranial percutaneous transluminal angioplasty (PTA)/stenting for intracranial stenosis during the period from 2005 to 2009 were investigated. A technical success was achieved in 98.3% of the patients, and 70.5% and 7.5% had a residual stenosis of < 30% and ≥ 50%, respectively. The incidence of ischemic complications and hemorrhagic complications was as low as 7.7% and 2.5%, respectively, but tended to increase in patients who underwent stenting. While a significant correlation with ischemic complications was observed in previously untreated patients and patients who underwent stenting followed by post-dilatation, a significant correlation with hemorrhagic complications was observed in patients who received emergency treatment and those treated between 24 hours and 14 days of the onset. Flexible intracranial stents are expected to contribute to improvement in the treatment outcome.
PMCID: PMC4508692  PMID: 24390191
intracranial stenosis; angioplasty; stenting
8.  A Study of Upper Extremity Training for Patients with Stroke Using a Virtual Environment System 
[Purpose] A virtual environment (VE) system was designed to facilitate the retraining of motor control by feedback of movement trajectory to patients with neurological impairments, such as stroke victims or those with an acquired brain injury. In this study, we quantitatively assessed motion trajectory of the upper extremity during VE in order to further understand the effect of paralyzed upper extremity movement in VE for each patient as well as the functional clinical evaluations. [Subjects and Methods] Six patients with stroke were participated in this study. The VE system consisted of a computer, an electromagnetic motion tracking device, which monitored and displayed patient movement on the computer, and the VE software, which provided the tools for creating training scenes. This system was used to facilitate motor relearning of the upper extremity for six patients with stroke. [Results] The results showed there were improvements in variability and accuracy of the arm movement in motion trajectory. In addition, the scores of clinical evaluations improved, and VE did not hinder motor relearning of the upper extremity, which is necessary for activities of daily living. [Conclusion] This VE system might be effective at facilitating motor relearning of the upper extremity for stroke patients.
PMCID: PMC3804986  PMID: 24259805
Hemiplegia; Upper extremity function; Virtual reality technology
9.  A Unique Type of Dural Arteriovenous Fistula at Confluence of Sinuses Treated with Endovascular Embolization: A Case Report 
Neurointervention  2013;8(1):34-40.
Dural arteriovenous fistula (DAVF) is classically defined as abnormal arteriovenous connections located within the dural leaflets. Though the exact etiology is still not clear, they are generally accepted as acquired lesions. However, some DAVFs formed as the congenital disorders are called dural arteriovenous malformations and these lesions with a marked cortical venous reflux are considered to be aggressive and warrant an early intervention. The authors describe a case of 35-year-old man presented with unique type of DAVF. The fistula was located adjacent to the confluence of venous sinuses with multiple feeders. The feeders drained into a large venous pouch just anterior to the confluence which had a bilateral venous drainage. This was associated with multiple cerebellar venous ectasia along the draining cortical vein. It was managed by staged endovascular procedures and complete cure could be achieved. The pathogenesis and technique of embolization of this complex fistula/malformation are also discussed.
PMCID: PMC3601279  PMID: 23515562
Dural arteriovenous fistula; Confluence of sinuses; Embolization; Cortical reflux; Varix
10.  Discovery of CS-0777: A Potent, Selective, and Orally Active S1P1 Agonist 
ACS Medicinal Chemistry Letters  2011;2(5):368-372.
CS-0777 (3) is phosphorylated in vivo, and the phosphate of CS-0777 (CS-0777-P) (4) acts as a selective S1P receptor-1 (S1P1) modulator. We report herein the synthesis of CS-0777 and CS-0777-P, pharmacological effects such as S1P1 and S1P3 agonist activity in vitro, peripheral blood lymphocyte lowering effects and the suppressive effect on experimental autoimmune encephalomyelitis (EAE), and also the pharmacokinetics in rats. CS-0777-P had ∼320-fold greater agonist activity for human S1P1 (EC50; 1.1 nM) relative to S1P3 (EC50; 350 nM). Following administration of single oral doses of 0.1 and 1 mg/kg of CS-0777 in rats, lymphocyte counts decreased significantly, with a nadir at 12 h postdose and recovery to vehicle control levels by 5 days postdose. In the EAE model compared to the vehicle-treated group, significant decreases in the cumulative EAE scores were observed for the 0.1 and 1 mg/kg CS-0777 groups in rats. CS-0777 is currently in clinical trials for the treatment of multiple sclerosis (MS).
PMCID: PMC4017972  PMID: 24900318
S1P1; agonist; CS-0777; lymphocyte; EAE; MS
11.  A System Utilizing Metal Hydride Actuators to Achieve Passive Motion of Toe Joints for Prevention of Pressure Ulcers: A Pilot Study 
This paper describes the influence of human toe movement on blood flow and the design of a toe joint passive motion system for preventing pressure ulcers. First, we measured lower extremity blood flow in the foot during active and passive motion of the toe to facilitate the design of new rehabilitation equipment. Also, the flexion and extension angles and the force of the toe joints were measured to determine appropriate specifications for the system. Increases in blood flow were observed at the external malleolus during movement. Flexion and extension angles and the force of the toe joints were found to differ significantly among participants. It is shown that a toe joint passive motion system can be effective in preventing pressure ulcers. On the basis of these results, a device using alloys of metal hydride (MH) as an actuator that is suitable for the system to initiate toe motion, was developed.
PMCID: PMC3350992  PMID: 22619724
12.  Genomic and proteomic characterization of the large Myoviridae bacteriophage ϕTMA of the extreme thermophile Thermus thermophilus 
Bacteriophage  2011;1(3):152-164.
A lytic phage, designated as ϕTMA, was isolated from a Japanese hot spring using Thermus thermophilus HB27 as an indicator strain. Electron microscopic examination showed that ϕTMA had an icosahedral head and a contractile tail. The circular double-stranded DNA sequence of ϕTMA was 151,483 bp in length, and its organization was essentially same as that of ϕYS40 except that the ϕTMA genome contained genes for a pair of transposase and resolvase, and a gene for a serine to asparagine substituted ortholog of the protein involved in the initiation of the ϕYS40 genomic DNA synthesis. The different host specificities of ϕTMA and ϕYS40 could be explained by the sequence differences in the C-terminal regions of their distal tail fiber proteins. The ΔpilA knockout strains of T. thermophilus showed simultaneous loss of sensitivity to their cognate phages, pilus structure, twitching motility and competence for natural transformation, thus suggesting that the phage infection required the intact host pili. Pulsed-field gel electrophoresis analysis of the ϕTMA and ϕYS40 genomes revealed that the length of their DNA exceeded 200 kb, indicating that the terminal redundancy is more than 30% of the closed circular form. Proteomic analysis of the ϕTMA virion using a combination of N-terminal sequencing and mass spectrometric analysis of peptide fragments suggested that the maturation of several proteins involved in the phage assembly process was mediated by a trypsin-like protease. The gene order of the phage structural proteins was also discussed.
PMCID: PMC3225780  PMID: 22164349
Thermus thermophilus; myovirus; genomics; antagonistic coevolution; proteomics
13.  A case study of new assessment and training of unilateral spatial neglect in stroke patients: effect of visual image transformation and visual stimulation by using a head mounted display system (HMD) 
Unilateral spatial neglect (USN) is most damaging to an older stroke patient who also has a lower performance in their activities of daily living or those elderly who are still working. The purpose of this study was to understand more accurately pathology of USN using a new HMD system.
Two stroke patients (Subject A and B) participated in this study after gaining their informed consent and they all had Left USN as determined by clinical tests. Assessments of USN were performed by using the common clinical test (the line cancellation test) and six special tests by using HMD system in the object-centered coordinates (OC) condition and the egocentric coordinates (EC) condition. OC condition focused the test sheet only by a CCD. EC condition was that CCD can always follow the subject's movement. Moreover, the study focused on the effect of the reduced image condition of real image and the arrows.
In Patient A who performed the common test and special tests of OC and EC conditions, the results showed that for the line cancellation test under the common condition, both of the percentage of the correct answers at the right and left sides in the test sheet was 100 percent. However, in the OC condition, the percentage of the correct answers at the left side in the test sheet was 44 percent and the right side was 94 percent. In the EC condition, the left side was 61 percent and the right side was 67 percent. In Patient B, according to the result of the use of reduced image condition and the arrows condition by HMD system, these line cancellation scores more increased than the score of the common test.
The results showed that the assessment of USN using an HMD system may clarify the left neglect area which cannot be easily observed in the clinical evaluation for USN. HMD may be able to produce an artificially versatile environment as compared to the common clinical evaluation and treatment.
PMCID: PMC2893202  PMID: 20470434
14.  Human Carboxymethylenebutenolidase as a Bioactivating Hydrolase of Olmesartan Medoxomil in Liver and Intestine 
The Journal of Biological Chemistry  2010;285(16):11892-11902.
Olmesartan medoxomil (OM) is a prodrug type angiotensin II type 1 receptor antagonist widely prescribed as an antihypertensive agent. Herein, we describe the identification and characterization of the OM bioactivating enzyme that hydrolyzes the prodrug and converts to its pharmacologically active metabolite olmesartan in human liver and intestine. The protein was purified from human liver cytosol by successive column chromatography and was identified by mass spectrometry to be a carboxymethylenebutenolidase (CMBL) homolog. Human CMBL, whose endogenous function has still not been reported, is a human homolog of Pseudomonas dienelactone hydrolase involved in the bacterial halocatechol degradation pathway. The ubiquitous expression of human CMBL gene transcript in various tissues was observed. The recombinant human CMBL expressed in mammalian cells was clearly shown to activate OM. By comparing the enzyme kinetics and chemical inhibition properties between the recombinant protein and human tissue preparations, CMBL was demonstrated to be the primary OM bioactivating enzyme in the liver and intestine. The recombinant CMBL also converted other prodrugs having the same ester structure as OM, faropenem medoxomil and lenampicillin, to their active metabolites. CMBL exhibited a unique sensitivity to chemical inhibitors, thus, being distinguishable from other known esterases. Site-directed mutagenesis on the putative active residue Cys132 of the recombinant CMBL caused a drastic reduction of the OM-hydrolyzing activity. We report for the first time that CMBL serves as a key enzyme in the bioactivation of OM, hydrolyzing the ester bond of the prodrug type xenobiotics.
PMCID: PMC2852926  PMID: 20177059
Enzymes; Metabolism/Drug; Protein/Purification; Site-directed Mutagenesis; Xenobiotics; CMBL; Activation; Esterase; Identification; Prodrug
15.  Proteomic analysis identifies proteins that continue to grow hepatic stem-like cells without differentiation 
Cytotechnology  2008;57(2):137-143.
To understand the molecular mechanism underlying vigorous proliferative activity of hepatic stem-like (HSL) cells, we performed two-dimensional electrophoresis to identify the proteins statistically more abundant in rapidly growing undifferentiated HSL cells than in sodium butyrate-treated differentiated HSL cells. Matrix-assisted laser desorption/ionization-time of flight mass spectrometry and Mascot search identified 6 proteins including prohibitin, vimentin, ezrin, annexin A3, acidic ribosomal phosphoprotein P0 and Grp75. Prohibitin and vimentin control the mitogen-activated protein (MAP) kinase pathway. Ezrin is phosphorylated by various protein-tyrosine kinases and modulates interactions between cytoskeletal and membrane proteins. Annexin A3 has a role in DNA synthesis. Acidic ribosomal phosphoprotein P0 and Grp75 play in protein synthesis. These results suggest that the proteins related to the MAP kinase cascade had some role in continuous proliferation of HSL cells without differentiation.
PMCID: PMC2553666  PMID: 19003158
Proteomics; Hepatic stem-like cells; Two-dimensional electrophoresis; Butyrate; Differentiation
16.  Cell-Specific Transcriptional Regulation of Human Leukotriene B4 Receptor Gene 
Leukotriene B4 (LTB4) is a lipid mediator that activates leukocytes and is involved in host defense and inflammation. BLT1, a high-affinity receptor for LTB4 (originally termed BLT), is expressed exclusively in inflammatory cells and is inducible in macrophages upon activation. The mechanisms of tissue-specific expression and induction of BLT1 are important for the understanding of mechanism of onset and the potential treatment of inflammatory disorders. Here, we report the genomic structure and a promoter analysis of the human BLT1 gene, with an emphasis on the mechanism of cell-specific transcription. No TATA or CAAT elements exist around the transcription initiation sites, but a GC-rich sequence is observed in this region. A reporter gene assay revealed that a region ∼80 basepair upstream from the initiator sequence is required for the basal transcription of the BLT1 gene. Sp1 was found to be a major activator of basal transcription by electrophoretic mobility shift assays and site-directed mutagenesis. The CpG sites of the BLT1 promoter region were highly methylated in BLT1-nonexpressing cells, but not methylated in BLT1-expressing cells. Further, methylation of this region in vitro inhibited the promoter activity to ∼15% of the control. Thus, methylation at CpG sites in the promoter region is important for cell-specific transcription of the BLT1 gene. The promoter region of the BLT1 gene is localized within the open reading frame (ORF) of the BLT2 gene, which encodes a low-affinity receptor for LTB4 (Yokomizo, T., K. Kato, K. Terawaki, T. Izumi, and T. Shimizu. 2000. J. Exp. Med. 192:421–431). To our knowledge, this is the first example of “promoter in ORF” in higher eukaryotes.
PMCID: PMC2193224  PMID: 10934229
leukotriene B4 receptor; inflammation; methylation; Sp1; THP-1 cell
17.  A Second Leukotriene B4 Receptor, Blt2 
Leukotriene B4 (LTB4) is a potent chemoattractant and activator of both granulocytes and macrophages. The actions of LTB4 appear to be mediated by a specific G protein–coupled receptor (GPCR) BLT1, originally termed BLT (Yokomizo, T., T. Izumi, K. Chang, Y. Takuwa, and T. Shimizu. 1997. Nature. 387:620–624). Here, we report the molecular cloning of a novel GPCR for LTB4, designated BLT2, which binds LTB4 with a Kd value of 23 nM compared with 1.1 nM for BLT1, but still efficiently transduces intracellular signaling. BLT2 is highly homologous to BLT1, with an amino acid identity of 45.2%, and its open reading frame is located in the promoter region of the BLT1 gene. BLT2 is expressed ubiquitously, in contrast to BLT1, which is expressed predominantly in leukocytes. Chinese hamster ovary cells expressing BLT2 exhibit LTB4-induced chemotaxis, calcium mobilization, and pertussis toxin–insensitive inhibition of adenylyl cyclase. Several BLT1 antagonists, including U 75302, failed to inhibit LTB4 binding to BLT2. Thus, BLT2 is a pharmacologically distinct receptor for LTB4, and may mediate cellular functions in tissues other than leukocytes. BLT2 provides a novel target for antiinflammatory therapy and promises to expand our knowledge of LTB4 function. The location of the gene suggests shared transcriptional regulation of these two receptors.
PMCID: PMC2193217  PMID: 10934230
BLT; cloning; gene cluster; leukotriene; low-affinity receptor
18.  Platelet-activating factor mediates acid-induced lung injury in genetically engineered mice 
Journal of Clinical Investigation  1999;104(8):1071-1076.
Adult respiratory distress syndrome (ARDS) is an acute lung injury of high mortality rate, and the molecular mechanisms underlying it are poorly understood. Acid aspiration–induced lung injury is one of the most common causes of ARDS, characterized by an increase in lung permeability, enhanced polymorphonuclear neutrophil (PMN) sequestration, and respiratory failure. Here, we investigated the role of platelet-activating factor (PAF) and the PAF receptor (PAFR) gene in a murine model of acid aspiration–induced lung injury. Overexpression of the PAFR gene in transgenic mice enhanced lung injury, pulmonary edema, and deterioration of gas exchange caused by HCl aspiration. Conversely, mice carrying a targeted disruption of the PAFR gene experienced significantly less acid-induced injury, edema, and respiratory failure. Nevertheless, the efficiency of PMN sequestration in response to acid aspiration was unaffected by differences in PAFR expression level. The current observations suggest that PAF is involved in the pathogenesis of acute lung injury caused by acid aspiration. Thus, inhibition of this pathway might provide a novel therapeutic approach to acute lung injury, for which no specific pharmaceutical agents are currently available.
PMCID: PMC481051  PMID: 10525045

Results 1-18 (18)