Publications by authors named "Tatsuya Uchida"

52 Publications

Catalytic Highly Regioselective C-H Oxygenation Using Water as the Oxygen Source: Preparation of O/O-Isotope-Labeled Compounds.

Org Lett 2021 Sep 8;23(18):7301-7305. Epub 2021 Sep 8.

Department of Chemistry, Graduate School of Science, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan.

We found that the oxygen atom of water is activated to iodosylbenzene derivatives via reversible hydrolysis of PhI(OOCR) and can be used to the oxygen source for ruthenium(bpga)-catalyzed site-selective C-H oxygenation. Ru(bpga)/PhI(OOCR)/HO system, sterically less bulky methinic and methylenic C-H bonds in various compounds can be converted to desired oxygen functional groups in a site-selective manner. Using this method, oxygen-isotope labeled compounds such as d-[3-O/O]-mannose can be prepared in a multigram scale.
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http://dx.doi.org/10.1021/acs.orglett.1c02812DOI Listing
September 2021

Primary diffuse large B-cell lymphoma of the cranial vault with Trousseau syndrome: a case report.

J Med Case Rep 2021 Aug 18;15(1):431. Epub 2021 Aug 18.

Department of Neurosurgery, Mitsui Memorial Hospital, 1 Kandaizumicho, Chiyoda-ku, Tokyo, Japan.

Background: It is extremely rare for primary non-Hodgkin's lymphomas to occur singly in the cranial vault. One case diagnosed as primary diffuse large B-cell lymphoma is reported, initially misdiagnosed as metastatic skull tumor, complicated with Trousseau syndrome.

Case Description: The patient was a 60-year-old Japanese woman with no particular previous medical history. In a head computed tomography examination for vertigo, bone destructive skull tumor covering the right frontal, parietal, and temporal bones was incidentally discovered. As positron emission tomography indicated an abnormal accumulation in the large intestine and multiple cerebral infarctions suspicious of Trousseau syndrome were observed on magnetic resonance images, a metastatic skull tumor due to colorectal cancer was first considered. However, various tumor markers were negative, and colonoscopic biopsy indicated no colorectal abnormality. After pathological examination of the resected tumor, it was diagnosed as diffuse large B-cell lymphoma. The tumor affected muscles and skin but did not develop in the brain or the dura mater. As further general examination revealed no other abnormalities, we considered that it was primary diffuse large B-cell lymphoma in the cranial vault associated with Trousseau syndrome. Treatment with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisolone and high-dose methotrexate reduced the residual lesion; coagulation abnormalities, which are frequently associated with Trousseau syndrome, also improved.

Conclusions: Skull tumors can result from a variety of malignancies, and their diagnosis may be complicated with Trousseau syndrome. However, even in cases of a single lesion in the cranial vault without invasion of the central nervous system, diffuse large B-cell lymphoma should be considered as a differential diagnosis.
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http://dx.doi.org/10.1186/s13256-021-02979-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8371799PMC
August 2021

Neurofibromatosis type 1 with subarachnoid hemorrhage due to multiple and de novo aneurysms: a case report.

J Med Case Rep 2021 Jul 30;15(1):411. Epub 2021 Jul 30.

Department of Neurosurgery, Mitsui Memorial Hospital, 1 Kandaizumicho, Chiyoda-ku, Tokyo, 101-8643, Japan.

Background: Neurofibromatosis type 1 causes various lesions in many organs including the skin, and the incidence of complications with intracranial aneurysms is 9-11%. Here we report a case of neurofibromatosis type 1 with subarachnoid hemorrhage due to multiple and de novo aneurysms.

Case Presentation: The patient was a 49-year-old Japanese woman with a history of neurofibromatosis type 1. She was transported to our hospital owing to disturbance of consciousness and was diagnosed with subarachnoid hemorrhage by computed tomography. Computed tomography angiography revealed multiple, small intracranial aneurysms, and we suspected that one of them in the peripheral branch of the left middle cerebral artery was the source of hemorrhage based on the distribution of hematoma. The patient underwent emergency surgery. Because it was difficult to identify an aneurysm in the most peripheral part of the left middle cerebral artery in the initial surgery, only one aneurysm was clipped. Later, a peripheral aneurysm was clipped using the navigation system. Because both aneurysms were small intracranial aneurysms (< 2 mm), either of them could be the source of hemorrhage. The postoperative course was good, and the patient was discharged in healthy condition. Because brain magnetic resonance imaging performed in the previous year did not find aneurysms at the same site, she was diagnosed with rupture of a de novo aneurysm. Neurofibromatosis type 1 might have caused the rupture of multiple intracranial aneurysms in a short period in this patient.

Conclusion: Neurofibromatosis type 1 may be complicated by the formation of multiple intracranial aneurysms in a short period.
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http://dx.doi.org/10.1186/s13256-021-02967-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8323238PMC
July 2021

Identification of the Facial Colliculus in Two-dimensional and Three-dimensional Images.

Neurol Med Chir (Tokyo) 2021 Jun 11;61(6):376-384. Epub 2021 May 11.

Department of Neurosurgery, The University of Tokyo.

The facial colliculus (FC), an important landmark for planning a surgical approach to brainstem cavernous malformation (BCM), is a microstructure; therefore, it may be difficult to identify on magnetic resonance imaging (MRI). Three-dimensional (3D) images may improve the FC-identification certainty; hence, this study attempted to validate the FC-identification certainty between two-dimensional (2D) and 3D images of patients with a normal brainstem and those with BCM. In this retrospective study, we included 10 patients with a normal brainstem and 10 patients who underwent surgery for BCM. The region of the FC in 2D and 3D images was independently identified by three neurosurgeons, three times in each case, using the method for continuously distributed test results (0-100). The intra- and inter-rater reliability of the identification certainty were confirmed using the intraclass correlation coefficient (ICC). The FC-identification certainty for 2D and 3D images was compared using the Wilcoxon signed-rank test. The ICC (1,3) and ICC (3,3) in both groups ranged from 0.88 to 0.99; therefore, the intra- and inter-rater reliability were good. In both groups, the FC-identification certainty was significantly higher for 3D images than for 2D images (normal brainstem group; 82.4 vs. 61.5, P = .0020, BCM group; 40.2 vs. 24.6, P = .0059 for the unaffected side, 29.3 vs. 17.3, P = .0020 for the affected side). In the normal brainstem and BCM groups, 3D images had better FC-identification certainty. 3D images are effective for the identification of the FC.
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http://dx.doi.org/10.2176/nmc.oa.2020-0417DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8258009PMC
June 2021

Microvascular Decompression Surgery for Elderly Patients: A Study Based on Proposals from the Joint Committee of the Japan Gerontological Society and the Japan Geriatrics Society.

Neurol Med Chir (Tokyo) 2020 Sep 15;60(9):468-474. Epub 2020 Aug 15.

Department of Neurosurgery, Mitsui Memorial Hospital.

The present study evaluated the indications for microvascular decompression (MVD) in elderly patients based on the new classification of the elderly population proposed by the joint committee of the Japan Gerontological Society and the Japan Geriatrics Society in 2017.Retrospective analysis of 171 patients with hemifacial spasm (HFS), trigeminal neuralgia (TN), and glossopharyngeal neuralgia (GPN) who underwent MVD in 2018. Patients were divided into three groups based on the proposal: old group, 75-89 years; pre-old group, 65-74 years; and not-old group, 64 years or younger. Preoperative comorbidities were divided into five types and the American Society of Anesthesiologists Physical Status (ASA-PS) was recorded. Outcome of the surgery and neurological complications were evaluated in June 2019.No decrease in activity of daily living occurred in any patient and surgical results showed no difference among the three groups. Rate of preoperative cardiovascular diseases was higher in both the pre-old and old groups compared with the not-old group (p <0.001 and Cramer V = 0.429). In terms of ASA-PS classification, only ASA-PS I and II were found, and rate of ASA-PS II was higher in the pre-old and old groups compared with the not-old group (p <0.001 and Cramer V = 0.407). Some patients suffered from elevated blood pressure after surgery, but were successfully managed.In conclusion, MVD for elderly patients can be achieved safely with careful patient selection and perioperative management. Data should be continuously accumulated for the future development of decision-making algorithm for MVD in the elderly.
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http://dx.doi.org/10.2176/nmc.oa.2020-0075DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7490598PMC
September 2020

Ruthenium-Catalyzed Asymmetric -Acyl Nitrene Transfer Reaction: Imidation of Sulfide.

Org Lett 2020 May 1;22(10):4021-4025. Epub 2020 May 1.

Faculty of Arts and Science, Kyushu University, Nishi-ku, Fukuoka 819-0395, Japan.

The asymmetric nitrene transfer reaction is a useful and strong tool for the construction of nitrogen functional groups such as sulfonyl amide and carbamic ester in a highly enantioselective manner. On the other hand, there is a substantial limitation in this filed: the transfer of -acyl amide via the corresponding nitrene intermediates is still difficult because -acyl nitrenes undergo undesired nitrene dimerization or Curtius rearrangement. Herein, we achieved highly enantioselective imidation of sulfides via catalytic acyl nitrene transfer with (OC)ruthenium-salen complex as the catalyst and 3-substituted 1,4,2-dioxazol-5-ones as the nitrene source. Complex can decompose dioxazolones to the desired -acyl nitrene intermediates without any activation via heating or UV irradiation, or transfer generating nitrene intermediates to the sulfur atom of sulfides with good to excellent enantioselectivities (≤98% ee) without diazene and isocyanate contamination.
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http://dx.doi.org/10.1021/acs.orglett.0c01373DOI Listing
May 2020

Non-Heme-Type Ruthenium Catalyzed Chemo- and Site-Selective C-H Oxidation.

Chem Asian J 2020 Mar 27;15(6):762-765. Epub 2020 Feb 27.

Faculty of Arts and Science, Kyushu University, 744, Motooka, Nishi-ku, Fukuoka, 819-0395, Japan.

Herein, we developed a Ru(II)(BPGA) complex that could be used to catalyze chemo- and site-selective C-H oxidation. The described ruthenium complex was designed by replacing one pyridyl group on tris(2-pyridylmethyl)amine with an electron-donating amide ligand that was critical for promoting this type of reaction. More importantly, higher reactivities and better chemo-, and site-selectivities were observed for reactions using the cis-ruthenium complex rather than the trans-one. This reaction could be used to convert sterically less hindered methyne and/or methylene C-H bonds of a various organic substrates, including natural products, into valuable alcohol or ketone products.
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http://dx.doi.org/10.1002/asia.202000134DOI Listing
March 2020

Ruthenium-Catalyzed Cross-Selective Asymmetric Oxidative Coupling of Arenols.

Org Lett 2020 Feb 27;22(4):1469-1474. Epub 2020 Jan 27.

Faculty of Arts and Science , Kyushu University , 744 Motooka, Nishi-ku , Fukuoka 819-0395 , Japan.

(Aqua)ruthenium(salen) complex achieved good to high chemo- and enantioselective oxidative cross-coupling of arenols. The catalytic system can be used to selectively produce -symmetric bis(arenol)s from the combination of C3- and C7-substituted 2-naphthols or phenols even when there is no significant difference in oxidation potential between the cross-coupling partners. This unique cross-selectivity is dominated by steric rather than electronic effects of the arenols and can be controlled by chemoselective single-electron oxidation and oxidative carbon-carbon bond formation.
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http://dx.doi.org/10.1021/acs.orglett.0c00048DOI Listing
February 2020

Involvement of Acidic Polysaccharide Ph-PS-2 and Protein in Initiation of Coccolith Mineralization, as Demonstrated by In Vitro Calcification on the Base Plate.

Mar Biotechnol (NY) 2018 Jun 4;20(3):304-312. Epub 2018 Apr 4.

School of Life Sciences, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo, 192-0392, Japan.

Coccolithophorids, unicellular marine microalgae, have calcified scales with elaborate structures, called coccoliths, on the cell surface. Coccoliths generally comprise a base plate, CaCO, and a crystal coat consisting of acidic polysaccharides. In this study, the in vitro calcification conditions on the base plate of Pleurochrysis haptonemofera were examined to determine the functions of the base plate and acidic polysaccharides (Ph-PS-1, -2, and -3). When EDTA-treated coccoliths (acidic polysaccharide-free base plates) or low pH-treated coccoliths (whole acidic polysaccharide-containing base plates) were used, mineralization was not detected on the base plate. In contrast, in the case of coccoliths which were decalcified by lowering of the pH and then treated with urea (Ph-PS-2-containing base plates), distinct aggregates, probably containing CaCO, were observed only on the rim of the base plates. Energy dispersive X-ray spectroscopy (EDS) confirmed that the aggregates contained Ca and O, although X-ray diffraction analysis did not reveal any evidence of crystalline materials. Also, in vitro mineralization experiments performed on EDTA-treated coccoliths using isolated acidic polysaccharides demonstrated that the Ca-containing aggregates were markedly formed only in the presence of Ph-PS-2. Furthermore, in vitro mineralization experiments conducted on protein-extracted base plates suggested that the coccolith-associated protein(s) are involved in the Ca deposition. These findings suggest that Ph-PS-2 associated with the protein(s) on the base plate rim initiates Ca binding at the beginning of coccolith formation, and some other factors are required for subsequent calcite formation.
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http://dx.doi.org/10.1007/s10126-018-9818-4DOI Listing
June 2018

Ruthenium-Catalyzed Chemo- and Enantioselective Hydrogenation of Isoquinoline Carbocycles.

J Org Chem 2018 04 26;83(7):3829-3839. Epub 2018 Mar 26.

Department of Chemistry, Faculty of Science , Kyushu University , 744 Motooka , Nishi-ku, Fukuoka 819-0395 , Japan.

A chemoselective hydrogenation of isoquinoline carbocycles was achieved by using the catalyst prepared from Ru(methallyl)(cod) and trans-chelate chiral ligand PhTRAP. The unique chemoselectivity achieved in this hydrogenation could be ascribed to the trans-chelation of the chiral ligand. The procedure for preparing the catalyst strongly affects the reproducibility of the carbocycle hydrogenation. Various 5-, 6-, 7-, and 8-substituted isoquinolines were selectively hydrogenated at their carbocycles to afford 5,6,7,8-tetrahydroisoquinolines as major products in high yields with moderate or good enantioselectivities. Some mechanistic studies suggested that the stereogenic center was created during the initial addition of H to the aromatic ring in the hydrogenation of 5-substituted isoquinolines. In other words, the stereochemical control was accompanied by the dearomatization.
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http://dx.doi.org/10.1021/acs.joc.8b00190DOI Listing
April 2018

Selection of a platinum-binding sequence in a loop of a four-helix bundle protein.

J Biosci Bioeng 2018 Feb 17;125(2):192-198. Epub 2017 Oct 17.

Department of Applied Life Science, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan. Electronic address:

Protein-metal hybrids are functional materials with various industrial applications. For example, a redox enzyme immobilized on a platinum electrode is a key component of some biofuel cells and biosensors. To create these hybrid materials, protein molecules are bound to metal surfaces. Here, we report the selection of a novel platinum-binding sequence in a loop of a four-helix bundle protein, the Lac repressor four-helix protein (LARFH), an artificial protein in which four identical α-helices are connected via three identical loops. We created a genetic library in which the Ser-Gly-Gln-Gly-Gly-Ser sequence within the first inter-helical loop of LARFH was semi-randomly mutated. The library was then subjected to selection for platinum-binding affinity by using the T7 phage display method. The majority of the selected variants contained the Tyr-Lys-Arg-Gly-Tyr-Lys (YKRGYK) sequence in their randomized segment. We characterized the platinum-binding properties of mutant LARFH by using quartz crystal microbalance analysis. Mutant LARFH seemed to interact with platinum through its loop containing the YKRGYK sequence, as judged by the estimated exclusive area occupied by a single molecule. Furthermore, a 10-residue peptide containing the YKRGYK sequence bound to platinum with reasonably high affinity and basic side chains in the peptide were crucial in mediating this interaction. In conclusion, we have identified an amino acid sequence, YKRGYK, in the loop of a helix-loop-helix motif that shows high platinum-binding affinity. This sequence could be grafted into loops of other polypeptides as an approach to immobilize proteins on platinum electrodes for use as biosensors among other applications.
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http://dx.doi.org/10.1016/j.jbiosc.2017.09.006DOI Listing
February 2018

Isolation of ESBL-producing Bacteria from Sputum in Community-acquired Pneumonia or Healthcare-associated Pneumonia Does Not Indicate the Need for Antibiotics with Activity against This Class.

Intern Med 2018 Feb 11;57(4):487-495. Epub 2017 Oct 11.

Departments of Medicine, Sugita Genpaku Memorial Obama Municipal Hospital, Japan.

Objective In the past decade, extended-spectrum β-lactamase (ESBL)-producing bacteria have increasingly frequently been isolated from various kinds of clinical specimens. However, the appropriate treatment of pneumonia in which ESBL-producing bacteria are isolated from sputum culture is poorly understood. To investigate whether or not ESBL-producing bacteria isolated from sputum in pneumonia cases should be treated as the causative bacteria. Methods and Patients In this retrospective study, we screened for patients, admitted between January 2009 and December 2015 in whom pneumonia was suspected and for whom sputum cultures yielded Escherichia coli or Klebsiella spp. isolates. We identified patients with community-acquired pneumonia (CAP) or healthcare-associated pneumonia (HCAP) from whom ESBL-producing bacteria had been isolated from sputum culture and to whom antibiotic treatment had been given with a diagnosis of pneumonia. We analyzed the patients' backgrounds and the effect of the antibiotic treatment for the initial 3-5 days. Results From 400 patients initially screened, 27 with ESBL-producing bacteria were secondarily screened. In this subset of patients, 15 were diagnosed with pneumonia, including 7 with CAP (5 E. coli and 2 K. pneumoniae) and 8 with HCAP (8 E. coli). These patients exhibited an average age of 84.1 years old, and 9 of 15 were men. No patients were initially treated with antimicrobials that are effective against isolated ESBL-producing bacteria. However, 13 of 15 patients showed improvement of pneumonia following the initial antibiotic treatment. Conclusion ESBL-producing bacteria isolated from sputum are not likely to be the actual causative organisms of pneumonia.
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http://dx.doi.org/10.2169/internalmedicine.8867-17DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5849542PMC
February 2018

Anastomotic Aneurysm Formation after High Flow Bypass Surgery: A Case Report with Histopathological Study.

NMC Case Rep J 2017 Oct 24;4(4):111-113. Epub 2017 Aug 24.

Department of Neurosurgery, Toranomon Hospital, Tokyo, Japan.

Bypass surgery is often used in the treatment of large and giant aneurysms. Major complications that often arise during the perioperative period include cranial nerve palsy, ischemic complications, and hyperperfusion. However, there have been a few reports about late onset complications such as anastomotic aneurysms. In particular, anastomotic aneurysm after high flow bypasses has never been reported. A 57-year-old woman who had been suffering from left eye pain was diagnosed with a large aneurysm of the left internal carotid artery (ICA) in the cavernous portion. She was treated with high flow bypass surgery using radial artery graft and proximal ICA ligation. One and a half year after surgery, a de novo aneurysm (7.5 mm in maximum diameter) was detected in the anastomotic site. To prevent rupture, the aneurysm was resected and the middle cerebral artery (MCA) was reconstructed via superficial temporal artery (STA)-MCA bypass. Postoperative course was uneventful and the anastomotic aneurysm did not recur until 2 years after second surgery. Histological evaluation of the anastomotic aneurysm demonstrated loss of smooth muscle cells and proliferation of neointima, features consistent with a true aneurysm. Interestingly, the above changes were prominent in the radial artery graft while the MCA was almost histologically intact. As such, intraoperative intimal damage and postoperative hemodynamic stress to the radial artery graft may be a cause of aneurysm formation. Anastomotic aneurysm may occur after high flow bypass, necessitating careful postoperative follow-up.
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http://dx.doi.org/10.2176/nmccrj.cr.2017-0037DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5629355PMC
October 2017

Leucocyte protein Trojan, a possible regulator of apoptosis.

APMIS 2017 Feb 28;125(2):106-113. Epub 2016 Dec 28.

Research Unit of Biomedicine, Department of Medical Microbiology and Immunology, University of Oulu, Oulu, Finland.

Trojan is a leucocyte-specific protein, cloned from chicken embryonic thymocyte cDNA library. The molecule is a type I transmembrane protein with an extracellular CCP domain, followed by two FN3 domains. Its cytoplasmic tail is predicted to possess a MAPK docking and a PKA phosphorylation sites. Trojan has been proposed to have an anti-apoptotic role based on its differential expression on developing thymocyte subpopulations. Using a chicken cell line, our in vitro studies showed that upon apoptosis induction, Trojan expression rises dramatically on the surface of surviving cells and gradually decreases towards its normal levels as cells recover. When sorted based on their expression levels of Trojan, cells with high expression appeared less susceptible to apoptotic induction than those bearing no or low levels of Trojan on their surface. The mechanism by which the molecule exerts its function is yet to be discovered. We found that cells overexpressing Trojan from a cDNA plasmid show elevated steady-state levels of intracellular calcium, suggesting the molecule is able to transmit cytoplasmic signals. The mechanistic nature of Trojan-induced signalling is a target of future investigation. In this article, we conducted a series of experiments that suggest Trojan as an anti-apoptotic regulator.
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http://dx.doi.org/10.1111/apm.12641DOI Listing
February 2017

Bypass Surgeries in the Treatment of Cerebral Aneurysms.

Acta Neurochir Suppl 2016 ;123:57-64

Department of Neurosurgery, Toranomon Hospital, 2-2-2 Toranomon, Minato-ku, Tokyo, 105-8470, Japan.

Background: During surgery for cerebral aneurysm, revascularization techniques are occasionally needed to (1) treat an aneurysm (trapping or flow alteration); (2) preserve blood flow during temporary parent artery occlusion (insurance); and (3) repair accidentally injured vessels (troubleshooting). Herein we present our surgical case experiences.

Methods: Revascularization modalities were employed in 33 (7.6 %) of 452 cases of surgically treated aneurysms. The aneurysm locations and associated required bypass procedures were: (1) 7 middle cerebral artery (MCA) aneurysms with 7 superficial temporal artery (STA)-MCA bypass procedures; (2) 10 internal carotid artery (ICA) aneurysms with 9 high-flow and 1 STA-MCA procedures; (3) 10 vertebro-basilar artery aneurysms with 2 high-flow, 6 occipital artery (OA)-posterior ICA, and 1 STA-superior cerebellar artery (SCA) procedures; (4) 1 posterior cerebral artery (PCA) aneurysm with OA-PCA bypass; and (5) 5 anterior cerebral artery aneurysms with 4 A3-A3 and 1 A3-STA-A3 procedure. Curative bypasses for aneurysmal treatment, temporary bypasses, and troubleshooting procedures were performed in 25, 3, and 5 cases, respectively.

Results: Among the 26 aneurysms treated via curative bypass, 16 aneurysms that were trapped or clipped using revascularization techniques had better outcomes (no aneurysmal rupture and 1 perforator infarction), whereas among the 10 aneurysms that could not be trapped or clipped and were thereby treated via flow alteration (e.g., bypass plus proximal artery clipping), 2 developed symptomatic infarction and 2 exhibited aneurysmal rupture after partial thrombosis. Patients whose bypass procedures were used for temporary parent artery occlusion (insurance) or troubleshooting had no complications.

Conclusion: Complex aneurysm clipping or trapping using bypass techniques yielded good results. In particular, perforator vessel ischemia still requires resolution. Flow alteration techniques leading to aneurismal thrombosis carried the risks of ischemic and hemorrhagic complications when applied to intracranial aneurysms. Bypasses for temporary use or troubleshooting were quite effective.
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http://dx.doi.org/10.1007/978-3-319-29887-0_8DOI Listing
October 2017

Expression of Glucocorticoid Receptors GRα and GRβ in Bullous Pemphigoid.

Acta Derm Venereol 2016 Nov;96(7):922-926

Department of Dermatology, University of Oulu, FIN-90029 Oulu, Finland.

First-line treatments of bullous pemphigoid (BP) are topical and systemic glucocorticoids (GC). The actions of GC are mediated by glucocorticoid receptors (GR), which exist in several isoforms, of which GRα and GRβ are the most important. In many inflammatory diseases, up-regulation of GRβ is associated with GC insensitivity. The aims of this study were to determine the expression of GRα and GRβ in patients with BP and to investigate the effect of prednisolone treatment on the expression of GR isoforms in BP. Quantitative real-time PCR (qPCR) analysis demonstrated that GR isoform mRNAs are expressed in peripheral blood mononuclear cells (PBMC) from patients with BP. Expression of GRα and GRβ protein was confirmed by immunohistochemical staining of BP skin biopsies and by Western blot analysis and flow cytometric analysis of PBMCs. During prednisolone treatment, GRα and GRβ expression varied markedly, but changes were not suitable as a clinical marker of GC sensitivity in patients with BP.
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http://dx.doi.org/10.2340/00015555-2443DOI Listing
November 2016

De novo design of protein-protein interactions through modification of inter-molecular helix-helix interface residues.

Biochim Biophys Acta 2016 May 9;1864(5):479-87. Epub 2016 Feb 9.

Department of Applied Sciences, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan. Electronic address:

For de novo design of protein-protein interactions (PPIs), information on the shape and chemical complementarity of their interfaces is generally required. Recent advances in computational PPI design have allowed for de novo design of protein complexes, and several successful examples have been reported. In addition, a simple and easy-to-use approach has also been reported that arranges leucines on a solvent-accessible region of an α-helix and places charged residues around the leucine patch to induce interactions between the two helical peptides. For this study, we adopted this approach to de novo design a new PPI between the helical bundle proteins sulerythrin and LARFH. A non-polar patch was created on an α-helix of LARFH around which arginine residues were introduced to retain its solubility. The strongest interaction found was for the LARFH variant cysLARFH-IV-3L3R and the sulerythrin mutant 6L6D (KD=0.16 μM). This artificial protein complex is maintained by hydrophobic and ionic interactions formed by the inter-molecular helical bundle structure. Therefore, by the simple and easy-to-use approach to create de novo interfaces on the α-helices, we successfully generated an artificial PPI. We also created a second LARFH variant with the non-polar patch surrounded by positively charged residues at each end. Upon mixing this LARFH variant with 6L6D, mesh-like fibrous nanostructures were observed by atomic force microscopy. Our method may, therefore, also be applicable to the de novo design of protein nanostructures.
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http://dx.doi.org/10.1016/j.bbapap.2016.02.008DOI Listing
May 2016

Abnormal discharges from the temporal neocortex after selective amygdalohippocampectomy and seizure outcomes.

J Clin Neurosci 2015 Nov 6;22(11):1797-801. Epub 2015 Aug 6.

Department of Neurosurgery, Tokyo Metropolitan Neurological Hospital, Tokyo, Japan.

The present study examined the relationship between residual discharges from the temporal neocortex postoperatively and seizure outcomes, in mesial temporal lobe epilepsy (MTLE) patients with hippocampal sclerosis (HS) who were treated with selective amygdalohippocampectomy (SelAH). Abnormal discharges from the temporal neocortex are often observed and remain postoperatively. However, no recommendations have been made regarding whether additional procedures to eliminate these discharges should be performed for seizure relief. We retrospectively analyzed 28 patients with unilateral MTLE and HS, who underwent transsylvian SelAH. The mean follow-up period was 29 months (range: 16-49). In the pre- and postresection states, electrocorticography (ECoG) was recorded for the temporal base and lateral temporal cortex. The extent of resection was not influenced by the results of the preresection ECoG. Even if residual abnormal discharges were identified on the temporal neocortex, no additional procedures were undertaken to eliminate these abnormalities. The postresection spike counts were examined to determine the postresective alterations in spike count, and the frequency of residual spike count. The seizure outcomes were evaluated in all patients using the Engel classification. The postoperative seizure-free rate was 92.9%. No significant correlations were seen between a decreasing spike count and seizure outcomes (p=0.9259), or between the absence of residual spikes and seizure outcomes (p=1.000). Residual spikes at the temporal neocortex do not appear to influence seizure outcomes. Only mesial temporal structures should be removed, and additional procedures to eliminate residual spikes are not required.
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http://dx.doi.org/10.1016/j.jocn.2015.03.063DOI Listing
November 2015

Characterization of the avian Trojan gene family reveals contrasting evolutionary constraints.

PLoS One 2015 24;10(3):e0121672. Epub 2015 Mar 24.

Division of Genetics and Genomics, The Roslin Institute and R(D)SVS, University of Edinburgh, Roslin, United Kingdom.

"Trojan" is a leukocyte-specific, cell surface protein originally identified in the chicken. Its molecular function has been hypothesized to be related to anti-apoptosis and the proliferation of immune cells. The Trojan gene has been localized onto the Z sex chromosome. The adjacent two genes also show significant homology to Trojan, suggesting the existence of a novel gene/protein family. Here, we characterize this Trojan family, identify homologues in other species and predict evolutionary constraints on these genes. The two Trojan-related proteins in chicken were predicted as a receptor-type tyrosine phosphatase and a transmembrane protein, bearing a cytoplasmic immuno-receptor tyrosine-based activation motif. We identified the Trojan gene family in ten other bird species and found related genes in three reptiles and a fish species. The phylogenetic analysis of the homologues revealed a gradual diversification among the family members. Evolutionary analyzes of the avian genes predicted that the extracellular regions of the proteins have been subjected to positive selection. Such selection was possibly a response to evolving interacting partners or to pathogen challenges. We also observed an almost complete lack of intracellular positively selected sites, suggesting a conserved signaling mechanism of the molecules. Therefore, the contrasting patterns of selection likely correlate with the interaction and signaling potential of the molecules.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0121672PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4372362PMC
February 2016

Unprecedented cell-selection using ultra-quick freezing combined with aquaporin expression.

PLoS One 2014 18;9(2):e87644. Epub 2014 Feb 18.

Department of Pharmacology, School of Medicine, Keio University, Tokyo, Japan.

Freezing is usually used for preservation and storage of biological samples; however, this process may have some adverse effects such as cell membrane damage. Aquaporin (AQP), a water channel protein, has been suggested to play some roles for cryopreservation although its molecular mechanism remains unclear. Here we show that membrane damage caused by ultra-quick freezing is rescued by the expression of AQP4. We next examine if the expression of AQP combined with ultra-quick freezing can be used to select cells efficiently under freezing conditions where most cells are died. CHO cells stably expressing AQP4 were exclusively selected from mixed cell cultures. Having identified the increased expression of AQP4 during ES cell differentiation into neuro-ectoderm using bioinformatics, we confirmed the improved survival of differentiated ES cells with AQP4 expression. Finally we show that CHO cells transiently transfected with Endothelin receptor A and Aqp4 were also selected and concentrated by multiple cycles of freezing/thawing, which was confirmed with calcium imaging in response to endothelin. Furthermore, we found that the expression of AQP enables a reduction in the amount of cryoprotectants for freezing, thereby decreasing osmotic stress and cellular toxicity. Taken together, we propose that this simple but efficient and safe method may be applicable to the selection of mammalian cells for applications in regenerative medicine as well as cell-based functional assays or drug screening protocols.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0087644PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3928110PMC
January 2015

Ruthenium-catalyzed oxidative kinetic resolution of unactivated and activated secondary alcohols with air as the hydrogen acceptor at room temperature.

Angew Chem Int Ed Engl 2014 Mar 12;53(12):3178-82. Epub 2014 Feb 12.

Department of Chemistry, Graduate School of Science, Kyushu University, Hakozaki, Higashi-ku, Fukuoka 812-8581 (Japan).

Enantiopure alcohols are versatile building blocks for asymmetric synthesis and the kinetic resolution (KR) of racemic alcohols is a reliable method for preparing them. Although many KR methods have been developed, oxidative kinetic resolution (OKR), in which dioxygen is used as the hydrogen acceptor, is the most atom-efficient. Dioxygen is ubiquitous in air, which is abundant and safe to handle. Therefore, OKR with air has been intensively investigated and the OKR of benzylic alcohols was recently achieved by using an Ir catalyst without any adjuvant. However, the OKR of unactivated alcohols remains a challenge. An [(aqua)Ru(salen)] catalyzed OKR with air as the hydrogen acceptor was developed, in which the aqua ligand is exchanged with alcohol and the Ru complex undergoes single electron transfer to dioxygen and subsequent alcohol oxidation. This OKR can be applied without any adjuvant to activated and unactivated alcohols with good to high enantioselectivity. The unique influence of substrate inhibition on the enantioselectivity of the OKR is also described.
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http://dx.doi.org/10.1002/anie.201310426DOI Listing
March 2014

Asymmetric nitrene transfer reactions: sulfimidation, aziridination and C-H amination using azide compounds as nitrene precursors.

Chem Rec 2014 Feb 22;14(1):117-29. Epub 2014 Jan 22.

Faculty of Arts and Science, Kyushu University, Hakozaki, Higashi-ku, Fukuoka, 812-8581, Japan; International Institute for Carbon-Neutral Energy Research (WPI-I2CNER), Kyushu University, Hakozaki, Higashi-ku, Fukuoka, 812-8581, Japan.

Nitrogen functional groups are found in many biologically active compounds and their stereochemistry has a profound effect on biological activity. Nitrene transfer reactions such as aziridination, C-H bond amination, and sulfimidation are useful methods for introducing nitrogen functional groups, and the enantiocontrol of the reactions has been extensively investigated. Although high enantioselectivity has been achieved, most of the reactions use (N-arylsulfonylimino)phenyliodinane, which co-produces iodobenzene, as a nitrene precursor and have a low atom economy. Azide compounds, which give nitrene species by releasing nitrogen, are ideal precursors but rather stable. Their decomposition needs UV irradiation, heating in the presence of a metal complex, or Lewis acid treatment. The examples of previous azide decomposition prompted us to examine Lewis acid and low-valent transition-metal complexes as catalysts for azide decomposition. Thus, we designed new ruthenium complexes that are composed of a low-valent Ru(II) ion, apical CO ligand, and an asymmetry-inducing salen ligand. With these ruthenium complexes and azides, we have achieved highly enantioselective nitrene transfer reactions under mild conditions. Recently, iridium-salen complexes were added to our toolbox.
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http://dx.doi.org/10.1002/tcr.201300027DOI Listing
February 2014

A surgical case of frontal lobe epilepsy due to focal cortical dysplasia accompanied by olfactory nerve enlargement: case report.

Neurol Med Chir (Tokyo) 2014 27;54(7):593-7. Epub 2013 Dec 27.

Department of Neurosurgery, Tokyo Metropolitan Neurological Hospital.

A 45-year-old man came to our clinic due to refractory general tonic seizure and an attack of unintended yelling. Magnetic resonance imaging (MRI) demonstrated mild cortical hyperintensity on fluid attenuated inversion recovery (FLAIR) image in the left basal frontal area. Enlargement of the left olfactory nerve was also detected below the affected gyrus. Subtotal resection of the MRI-visible epileptogenic lesion was performed without any neurological deficit. The final pathological diagnosis was focal cortical dysplasia (FCD) type IIa. Seizures and yelling attacks subsided after surgery. Extracerebral abnormalities, including cranial nerve enlargement, are common in patients with hemimegalencephaly. However, such abnormalities are rare with FCD.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4533458PMC
http://dx.doi.org/10.2176/nmc.cr.2013-0173DOI Listing
October 2016

TIM-family molecules in embryonic hematopoiesis: fetal liver TIM-4(lo) cells have myeloid potential.

Exp Hematol 2014 Mar 4;42(3):230-40. Epub 2013 Dec 4.

Institute of Diagnostics, Department of Medical Microbiology and Immunology, University of Oulu, Oulu, Finland.

Trans-membrane (or T cell) immunoglobulin and mucin (TIM) molecules are known regulators of immune response whose function in hematopoiesis is unknown. Earlier, we found that tim-1 and tim-4 are expressed by CD45(+) cells in the para-aortic region of chicken embryo. Because the para-aortic region is a known site for hematopoietic stem cell (HSC) and hematopoietic progenitor cell (HPC) differentiation and expansion, we hypothesize that TIM molecules have a role in hematopoiesis. To study this role further, we analyzed TIM expression more precisely in chicken para-aortic region and mouse fetal liver hematopoietic cells. Additionally, we examined the hematopoietic potential of TIM-4(+) mouse fetal liver cells with a colony-forming assay. tim-1 gene expression was detected in chicken and mouse embryos in the aorta-gonads-mesonephros-region at the time of HSC emergence, whereas tim-3 mRNA was widely expressed in different tissues. tim-4 expression was restricted to fetal liver CD45(+)F4/80(+) cells. Moreover, two TIM-4(+) populations were distinguished: F4/80(hi)TIM-4(hi) and F4/80(lo)TIM-4(lo). F4/80(hi)TIM-4(hi) cells had no hematopoietic potential and were morphologically similar to mature macrophages, suggesting that they are yolk sac-derived macrophages. Instead, many of the F4/80(lo)TIM-4(lo) cells were c-kit(+) and Sca-1(+) and had primitive morphology and multilineage colony-forming ability. In addition, F4/80(lo)TIM-4(lo) cells included a considerable population expressing ER-MP12, a known marker for macrophage colony-forming cells and other myeloid progenitors. We conclude that TIM molecules are expressed in embryonic hematopoietic tissues in chicken and mouse and that in fetal liver, TIM-4 is expressed by myeloid progenitor cells.
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http://dx.doi.org/10.1016/j.exphem.2013.11.014DOI Listing
March 2014

Enantio- and regioselective intermolecular benzylic and allylic C-H bond amination.

Angew Chem Int Ed Engl 2013 Feb 10;52(6):1739-42. Epub 2013 Jan 10.

Department of Chemistry, Faculty of Science, Graduate School, and International Institute for Carbon-Neutral Energy Research, Kyushu University, Hakozaki, Higashi-ku, Fukuoka 812-8581, Japan.

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http://dx.doi.org/10.1002/anie.201208906DOI Listing
February 2013

Ru(CO)-salen-catalyzed synthesis of enantiopure aziridinyl ketones and formal asymmetric synthesis of (+)-PD 128907.

Org Lett 2012 Sep 28;14(17):4658-61. Epub 2012 Aug 28.

Department of Chemistry, Faculty of Science, Graduate School, Kyushu University, Hakozaki, Fukuoka 812-8581, Japan.

Aziridination of vinyl ketones using SESN(3) in the presence Ru(CO)-salen complex 1 provides the enantiopure aziridinyl ketones that can serve as useful chiral building blocks. A formal asymmetric synthesis of (+)-PD 128907 was achieved in an eight-step sequence via aziridination.
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http://dx.doi.org/10.1021/ol302095rDOI Listing
September 2012

Asymmetric epoxidation of conjugated olefins with dioxygen.

Angew Chem Int Ed Engl 2012 Aug 23;51(33):8243-6. Epub 2012 Jul 23.

Department of Chemistry, Faculty of Science, Graduate School, and International Institute for Carbon-Neutral Energy Research (WPI-I2CNER), Kyushu University, Hakozaki, Higashi-ku, Fukuoka 812-8581, Japan.

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http://dx.doi.org/10.1002/anie.201201848DOI Listing
August 2012

Asymmetric olefin aziridination using a newly designed Ru(CO)(salen) complex as the catalyst.

Chem Commun (Camb) 2012 Jul 11;48(57):7188-90. Epub 2012 Jun 11.

Department of Chemistry, Faculty of Science, Graduate School, Kyushu University, Hakozaki, Higashi-ku Fukuoka 812-8581, Japan.

Highly enantioselective and good to high-yielding aziridination of conjugated and non-conjugated terminal olefins and cyclic olefins was achieved using a newly designed Ru(CO)(salen) complex as the catalyst in the presence of SESN(3) under mild conditions.
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http://dx.doi.org/10.1039/c2cc32997bDOI Listing
July 2012

Matrix metalloproteinase levels in peritoneal effluents were increased in a patient with appendicitis undergoing continuous ambulatory peritoneal dialysis.

Clin Exp Nephrol 2012 Jun 21;16(3):501-4. Epub 2011 Dec 21.

Department of Urology, Isesaki Municipal Hospital, Isesaki, Gunma, Japan.

A differential diagnosis of common bacterial peritonitis and appendicitis is difficult in continuous ambulatory peritoneal dialysis (CAPD) patients, and thus the definite diagnosis of appendicitis is often delayed. In this case, a 60-year-old man undergoing CAPD was at first diagnosed with bacterial peritonitis but not appendicitis, and antibiotics were administered. The number of leukocytes in the peritoneal effluent decreased mildly, but the level of C-reactive protein continued to be high and the pain aggravated. When the catheter was removed, suppurative appendicitis was confirmed for the first time. Levels of matrix metalloproteinase (MMP)-2 and -9 in peritoneal effluents were markedly high. Appendicitis should be diagnosed as early as possible because MMPs directly injure the peritoneum via degradation of extracellular matrix proteins. Future studies in a greater numbers of cases of appendicitis are required.
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http://dx.doi.org/10.1007/s10157-011-0576-0DOI Listing
June 2012

Evaluation of hydrogenated resin acids as molecular markers for tire-wear debris in urban environments.

Environ Sci Technol 2011 Dec 2;45(23):9990-7. Epub 2011 Nov 2.

Faculty of Life Sciences, Tokyo University of Pharmacy and Life Sciences, Hachioji, Tokyo 192-0392, Japan.

To propose new molecular markers for tire-wear emissions, four dihydroresin acids, that is, 8-isopimaren-18-oic acid (I), 8-pimaren-18-oic acid (II), 13β(H)-abieten-18-oic acid (III), and 13α(H)-abiet-8-en-18-oic acid (IV), were identified and investigated for source specificities, distributions, and environmental stabilities. The absence of I-IV in natural sources and the linear correlations between dihydroresin acids with different skeletons in tires and in environmental samples demonstrated that I-IV are specific markers for synthetic rubbers. The ratio of III + IV to the sum of III + IV plus abietic acid showed the resin acids distribution between different environmental compartments receiving contributions from traffic and natural sources. The physicochemical properties and results of photolysis experiments suggested that I-IV can set lower limits for tire-wear contributions to environmental loads of particulate matter (PM) and polycyclic aromatic hydrocarbons with molecular weight ≥202. By comparing III + IV concentrations or (III+IV)/pyrene or (III+IV)/benzo[a]pyrene ratios in tires and those in environmental matrices, the contributions of tire-wear emissions to PM, pyrene, and benzo[a]pyrene were estimated to be 0.68 ± 0.54%, 6.9 ± 4.8%, and 0.37 ± 0.18% in roadside PM and 0.83 ± 0.21%, 0.88 ± 0.52%, and 0.08 ± 0.06% in rooftop PM.
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http://dx.doi.org/10.1021/es202156fDOI Listing
December 2011
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