129 research outputs found
Online Automated Micro Sample Preparation for High-Performance Liquid Chromatography
Sample preparation is one of the most labor-intensive and time-consuming operations in sample analysis. Sample preparation strategies include the exhaustive or non-exhaustive extraction of analytes from matrices. Online coupling of sample preparation with the separation system is regarded as an important goal. In-tube solid-phase microextraction (SPME) is an effective sample preparation technique that uses an open tubular fused-silica capillary column as an extraction device. In-tube SPME is useful for trace enrichment, automated sample cleanup, and rapid online analysis. Moreover, this method can be used to determine the analytes in complex matrices by direct sample injection or merely by simple sample treatment such as filtration. In-tube SPME is frequently combined with high-performance liquid chromatography (HPLC) using online column-switching techniques. Various operating systems and new sorbent materials have been reported to improve extraction efficiency, such as sorption capacity and selectivity. This chapter discusses efficient micro sample preparation techniques for HPLC, especially online automated in-tube SPME
Well-designed bone-seeking radiolabeled compounds for diagnosis and therapy of bone metastases
Bone-seeking radiopharmaceuticals are frequently used as diagnostic agents in nuclear medicine, because they can detect bone disorders before anatomical changes occur. Furthermore, their effectiveness in the palliation of metastatic bone cancer pain has been demonstrated in the clinical setting. With the aim of developing superior bone-seeking radiopharmaceuticals, many compounds have been designed, prepared, and evaluated. Here, several well-designed bone-seeking compounds used for diagnostic and therapeutic use, having the concept of radiometal complexes conjugated to carrier molecules to bone, are reviewed. © 2015 Kazuma Ogawa and Atsushi Ishizaki
骨指向性輸送担体としてアスパラギン酸ペプチドを用いた放射標識化合物の基礎的検討
13301甲第4893号博士(創薬科学)金沢大学博士論文要旨Abstract 以下に掲載:1. Annals of Nuclear Medicine Japanese Society of Nuclear Medicine. 共著者:Atsushi Ishizaki, Kenji Mishiro, Kazuhiro Shiba, Hirofumi Hanaoka, Seigo Kinuya, Akira Odani, Kazuma Ogawa 2. Scientific Reports 7(1) pp.13971 2017. Nature Publishing Group. 共著者:Kazuma Ogawa, Atsushi Ishizaki, Kenichiro Takai, Yoji Kitamura, Akira Makino, Takashi Kozaka, Yasushi Kiyono, Kazuhiro Shiba, Akira Odan
Immunogenicity and Antigenicity of Allogeneic Amniotic Epithelial Transplants Grafted to the Cornea, Conjunctiva, and Anterior Chamber
PURPOSE. To determine the immunogenic characterization of amniotic epithelium (AE), by examining the fate of allogeneic AE grafts heterotopically transplanted in the eye. METHODS. Intact AE from enhanced green fluorescence protein (EGFP) transgenic mice (C57BL/6 background) and wild-type C57BL/6 mice were transplanted onto cornea or conjunctiva, or inserted into the anterior chamber (AC) of normal BALB/c mice, C57BL/6 mice, or BALB/c mice presensitized to donor antigens. For repeated AE transplantation experiments, AE was grafted in the other eye 7 days after the first grafting. Graft fate was assessed clinically and histologically at selected intervals after grafting. Infiltrating inflammatory cells were examined immunohistochemically. Sensitization to alloantigens by AE was assessed by the delayed hypersensitivity (DH) response. RESULTS. In normal recipients, GFP ϩ cells were absent in EGFP donor-derived AE grafts by day 21 on cornea and by day 7 on conjunctiva. AE grafts implanted in the AC survived for Ͼ8 weeks. In presensitized recipients and recipients that underwent repeated AE implantation, graft survival was markedly shorter than in normal recipients. DH was induced at 2 weeks, but failed to be induced at 4 weeks after grafting on cornea or at 8 weeks after grafting on conjunctiva and in the AC of normal recipients. CONCLUSIONS. Fresh allogeneic AE expressed immunogenicity when placed on the ocular surface, although no memory of allospecific DH was acquired. Allogeneic AE is clearly vulnerable to immune rejection in specifically sensitized recipients
JARE-43 ジンコウ ジシン タンサ ニ オケル スチームドリル ニ ヨル ハッパコウ クッサク
第43次日本南極地域観測隊(JARE-43)は,JARE-41に引き続いてみずほ高原にて人工地震探査実験を実施した.JARE-41と同様に,7ケ所の発破孔の掘削にはスチーム噴出式氷床掘削ドリルを用いた.掘削作業時間は,直径35-40 cm,深さ23.5-28.7 mの発破孔を掘削するのに,7-8時間であった.平均掘削速度は3.25 m/hrであった.A seismic exploration was accomplished in the austral summer of 2001-2002 by the 43rd Japanese Antarctic Research Expedition (JARE-43) along a profile oblique to that held by JARE-41 on the Mizuho Plateau, East Antarctica. We used a steam type drilling system to obtain seven blasting boreholes. We spent 7 to 8 hours to make an enough depth of the hole for one shot point. The holes were 35 to 40 cm in diameter and 23.5 to 28.7 m in depth. The average drilling speed was 3.25 m/hr
Development of novel radiogallium-labeled bone imaging agents using oligo-aspartic acid peptides as carriers
金沢大学疾患モデル総合研究センター68Ga (T1/2 = 68 min, a generator-produced nuclide) has great potential as a radionuclide for clinical positron emission tomography (PET). Because poly-glutamic and poly-aspartic acids have high affinity for hydroxyapatite, to develop new bone targeting 68Ga-labeled bone imaging agents for PET, we used 1,4,7,10-tetraazacyclododecane-1,4,7,10- tetraacetic acid (DOTA) as a chelating site and conjugated aspartic acid peptides of varying lengths. Subsequently, we compared Ga complexes, Ga-DOTA-(Asp)n (n = 2, 5, 8, 11, or 14) with easy-to-handle 67Ga, with the previously described 67Ga-DOTA complex conjugated bisphosphonate, 67Ga-DOTA-Bn-SCN-HBP. After synthesizing DOTA-(Asp)n by a Fmoc-based solid-phase method, complexes were formed with 67Ga, resulting in 67Ga-DOTA-(Asp)n with a radiochemical purity of over 95% after HPLC purification. In hydroxyapatite binding assays, the binding rate of 67Ga-DOTA-(Asp)n increased with the increase in the length of the conjugated aspartate peptide. Moreover, in biodistribution experiments, 67Ga-DOTA-(Asp) 8, 67Ga-DOTA-(Asp)11, and 67Ga-DOTA- (Asp)14 showed high accumulation in bone (10.5±1.5, 15.1±2.6, and 12.8±1.7% ID/g, respectively) but were barely observed in other tissues at 60 min after injection. Although bone accumulation of 67Ga-DOTA-(Asp)n was lower than that of 67Ga-DOTA-Bn-SCN-HBP, blood clearance of 67Ga-DOTA-(Asp)n was more rapid. Accordingly, the bone/blood ratios of 67Ga-DOTA-(Asp) 11 and 67Ga-DOTA-(Asp)14 were comparable with those of 67Ga-DOTA-Bn-SCN-HBP. In conclusion, these data provide useful insights into the drug design of 68Ga-PET tracers for the diagnosis of bone disorders, such as bone metastases. © 2013 Ogawa et al.CC-BY 4.
Transmesocolic Hernia of the Ascending Colon with Intestinal Obstruction
An internal hernia may be either congenital or acquired. The reported incidence of such hernias is 1–2%. In rare cases, internal hernias are the cause of small bowel obstruction, with a reported incidence of 0.2–0.9%. Transmesocolic hernia of the ascending colon is especially rare. We report a case of transmesocolic hernia of the ascending colon with intestinal obstruction diagnosed preoperatively. A 91-year-old Japanese female was admitted to our hospital with abdominal distention and vomiting of 3 days duration. She had no past history of any abdominal surgery. Abdominal examination revealed distention and tenderness in the right iliac fossa. Abdominal computed tomography revealed ileus in the sac at the left side of the ascending colon and dilatation of the oral side of the intestine. We diagnosed a transmesocolic hernia of the ascending colon with intestinal obstruction and performed emergency surgery. At the time of operation, there was internal herniation of ileal loops through a defect in the ascending mesocolon, without any strangulation of the small bowel. The contents were reduced and the tear in the ascending mesocolon was closed. The postoperative course was uneventful and the patient was discharged 14 days after surgery. In conclusion, preoperative diagnosis of bowel obstruction caused by a congenital mesocolic hernia remains difficult despite the techniques currently available, so it is important to consider the possibility of a transmesocolic hernia when diagnosing a patient with ileus with no past history of abdominal surgery
The Japanese space gravitational wave antenna; DECIGO
DECi-hertz Interferometer Gravitational wave Observatory (DECIGO) is the future
Japanese space gravitational wave antenna. DECIGO is expected to open a new window of
observation for gravitational wave astronomy especially between 0.1 Hz and 10 Hz, revealing
various mysteries of the universe such as dark energy, formation mechanism of supermassive
black holes, and inflation of the universe. The pre-conceptual design of DECIGO consists of
three drag-free spacecraft, whose relative displacements are measured by a differential Fabry–
Perot Michelson interferometer. We plan to launch two missions, DECIGO pathfinder and pre-
DECIGO first and finally DECIGO in 2024
DECIGO pathfinder
DECIGO pathfinder (DPF) is a milestone satellite mission for DECIGO (DECi-hertz Interferometer Gravitational wave Observatory) which is a future space gravitational wave antenna. DECIGO is expected to provide us fruitful insights into the universe, in particular about dark energy, a formation mechanism of supermassive black holes, and the inflation of the universe. Since DECIGO will be an extremely large mission which will formed by three drag-free spacecraft with 1000m separation, it is significant to gain the technical feasibility of DECIGO before its planned launch in 2024. Thus, we are planning to launch two milestone missions: DPF and pre-DECIGO. The conceptual design and current status of the first milestone mission, DPF, are reviewed in this article
Evaluation of Ga-DOTA-(D-Asp)n as bone imaging agents: D-aspartic acid peptides as carriers to bone
金沢大学新学術創成研究機構67Ga-DOTA-(L-Asp)11 and 67Ga-DOTA-(L-Asp)14, which have been developed as bone imaging agents, showed a high accumulation in bone and a rapid blood clearance in mice. However, peptides composed of D-amino acids are more stable in vivo than those composed of their L-equivalents. In this study, 67Ga-DOTA-(D-Asp)n (n = 2, 5, 8, 11, or 14) were synthesized using the Fmoc-based solid-phase methodology and evaluated. In hydroxyapatite binding assay, binding of 67Ga-DOTA-(D-Asp)n tended to increase with increasing length of the amino acid chain. 67Ga-DOTA-(D-Asp)11 and 67Ga-DOTA-(D-Asp)14 caused a high accumulation of radioactivity in the bones of the mice. However, the results for 67Ga-DOTA-(D-Asp)n and 67Ga-DOTA-(L-Asp)n were comparable. In urine analyses, the proportion of intact complex after injection of 67Ga-DOTA-(D-Asp)14 was significantly higher than that of 67Ga-DOTA-(L-Asp)14. Although 67Ga-DOTA-(D-Asp)14 was more stable than 67Ga-DOTA-(L-Asp)14, the properties of 67Ga-DOTA-(D-Asp)n and 67Ga-DOTA-(L-Asp)n as bone imaging agents may be comparable. © 2017 The Author(s)
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