Australia and Japan collaboration in Antarctic Science: 2nd Phase

第3回極域科学シンポジウム/第34回極域生物シンポジウム 11月26日（月） 統計数理研究所 ３階セミナー

The comparison of real gas and ideal gas models for compressor design

project TK03030121 Conceptual Design of an Innovative Safety System for Gas-cooled Nuclear Reactor

Toll-like receptor 4-dependent upregulation of cytokines in a transgenic mouse model of Alzheimer's disease

<p>Abstract</p> <p>Background</p> <p>Aβ deposits in the brains of patients with Alzheimer's disease (AD) are closely associated with innate immune responses such as activated microglia and increased cytokines. Accumulating evidence supports the hypothesis that innate immune/inflammatory responses play a pivotal role in the pathogenesis of AD: either beneficial or harmful effects on the AD progression. The molecular mechanisms by which the innate immune system modulates the AD progression are not well understood. Toll-like receptors (TLRs) are first-line molecules for initiating the innate immune responses. When activated through TLR signaling, microglia respond to pathogens and damaged host cells by secreting chemokines and cytokines and express the co-stimulatory molecules needed for protective immune responses to pathogens and efficient clearance of damaged tissues. We previously demonstrated that an AD mouse model homozygous for a destructive mutation of TLR4 has increases in diffuse and fibrillar Aβ deposits as well as buffer-soluble and insoluble Aβ in the brain as compared with a TLR4 wild-type AD mouse model. Here, we investigated the roles of TLR4 in Aβ-induced upregulation of cytokines and chemokines, Aβ-induced activation of microglia and astrocytes and Aβ-induced immigration of leukocytes.</p> <p>Methods</p> <p>Using the same model, levels of cytokines and chemokines in the brain were determined by multiplex cytokine/chemokine array. Activation of microglia and astrocytes and immigration of leukocytes were determined by immunoblotting and immunohistochemistry followed by densitometry and morphometry, respectively.</p> <p>Results</p> <p>Levels of tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-10 and IL-17 in the brains of TLR4 wild-type AD mice were significantly higher than those in TLR4 wild-type non-transgenic littermates. Such increases in cytokines were not found in TLR4 mutant AD mice as compared with TLR4 mutant non-transgenic littermates. Although expression levels of CD11b (a microglia marker) and GFAP (a reactive astrocyte marker) in the brains of TLR4 mutant AD mice were higher than those in TLR4 wild type AD mice, no difference was found in levels of CD45 (common leukocyte antigen).</p> <p>Conclusion</p> <p>This is the first demonstration of TLR4-dependent upregulation of cytokines in an AD mouse model. Our results suggest that TLR4 signaling is involved in AD progression and that TLR4 signaling can be a new therapeutic target for AD.</p

Modeling of hysteretic Schottky diode-like conduction in Pt/BiFeO3/SrRuO3 switches

The hysteresis current-voltage (I-V) loops in Pt/BiFeO3/SrRuO3 structures are simulated using a Schottky diode-like conduction model with sigmoidally varying parameters, including series resistance correction and barrier lowering. The evolution of the system is represented by a vector in a 3D parameter space describing a closed trajectory with stationary states. It is shown that the hysteretic behavior is not only the result of a Schottky barrier height (SBH) variation arising from the BiFeO3 polarization reversal but also a consequence of the potential drop distribution across the device. The SBH modulation is found to be remarkably lower (0.5 eV). It is also shown that the p-type semiconducting nature of BiFeO3 can explain the large ideality factors (>6) required to simulate the I-V curves as well as the highly asymmetric set and reset voltages (4.7 V and 1.9 V) exhibited by our devices

Hypoparathyroidism in an Egyptian child with Hutchinson-Gilford progeria syndrome: a case report

<p>Abstract</p> <p>Introduction</p> <p>Hutchinson-Gilford progeria syndrome is a rare genetic disorder. It is reported to be present in one in eight million and is characterized by severe growth failure, early loss of hair, lipodystrophy, scleroderma, decreased joint mobility, osteolysis, early atherosclerosis and facial features that resemble those of an aged person. Apart from diabetes mellitus, there are no reported abnormalities of thyroid, parathyroid, pituitary or adrenal function. Here, we report the case of a 10-year-old Egyptian child with Hutchinson-Gilford progeria syndrome and hypoparathyroidism.</p> <p>Case presentation</p> <p>A 10-year-old Egyptian boy was referred to our institution for an evaluation of recurrent attacks of muscle cramps, paresthesia of his fingertips and perioral numbness of two months duration. On examination, we found dilated veins present over his scalp with alopecia and frontal bossing, a beaked nose, thin lips, protruding ears, a high pitched voice with sparse hair over his eyebrows and eyelashes and micrognathia but normal dentition. His eyes appeared prominent and our patient appeared to have poor sexual development. A provisional diagnosis of progeria was made, which was confirmed by molecular genetics study. Chvostek's and Trousseau's signs were positive. He had low total calcium (5.4 mg/dL), low ionized calcium (2.3 mg/dL), raised serum phosphate (7.2 mg/dL), raised alkaline phosphatase (118 U/L) and low intact parathyroid hormone (1.2 pg/mL) levels. He was started on oral calcium salt and vitamin D; his symptoms improved with the treatment and his serum calcium, urinary calcium and alkaline phosphates level were monitored every three months to ensure adequacy of therapy and to avoid hypercalcemia.</p> <p>Conclusion</p> <p>Routine checking of serum calcium, phosphorus and parathyroid hormone will help in the early detection of hypoparathyrodism among children with progeria.</p

ナンキョク ケンキュウ カガク イインカイ ノ レンゾク プランクトン サイシュウキ センモンカ グループ ワークショップ ホウコク

2010年11月22-26日に国立極地研究所にて「南極研究科学委員会(以下SCAR)連続プランクトン採集器(以下CPR)専門家グループワークショップ」を開催した.4カ国から12名が参加し,南大洋CPR観測実務担当者の間で,観測データの品質管理,種同定やデータ分析手法の再確認,及び今後の活動についての詳細な討議を行った.前半は文献資料及び顕微鏡観察を通して,動物プランクトンの分類群ごとに種同定の情報交換及び具体的な分類カテゴリーの統一を図った.まとめられた種同定基準を用いて新たにマニュアルを作成することとなった.後半はデータ分析手法とデータマネージメント,さらには将来的な観測計画を確認した.今後,定期的にワークショップを開催し,各国間で統一された試料処理及びデータ管理を維持していくことで合意した."Southern Ocean Continuous Plankton Recorder (SO-CPR) Standards Workshop: SCAR Expert Group on CPR Research" was held at the National Institute of Polar Research (NIPR) on 22-26 November 2011. Twelve participants from four countries attended. The purposes of the workshop were to ensure that consistent and high standards of species identification, methodology, and data quality were being maintained amongst all participants and laboratories in the SO-CPR survey, and to discuss future contributions of the SO-CPR program to a global CPR network. The first three and a half days of the workshop were focused on assessing the accuracy and consistency of species identifications. We concluded that our species identifications and procedures are accurate and uniform, and that the SO-CPR database is of the highest possible standard. Certain taxonomic criteria developed at the workshop will be described in a new laboratory procedures manual. Four major gaps in the database (spatial, temporal, taxonomic, and data analysis gaps) were identified and discussed. Participants concurred that there should be more regular workshops to ensure that the high standards of the SO-CPR program are maintained

Keratoconus associated with choroidal neovascularization: a case report

<p>Abstract</p> <p>Introduction</p> <p>Keratoconus and choroidal neovascularization can occur as a result of dysfunction of the epithelium and its basement membrane.</p> <p>Case presentation</p> <p>A 17-year-old Asian man, who was diagnosed with myopic choroidal neovascularization in both eyes and who subsequently underwent intravitreal injection of ranibizumab (Lucentis^®) five times over six months, presented with further vision decrease and pain in his right eye. Examination showed corneal steepening and stromal edema in the inferocentral cornea of his right eye, both of which were indicative of advanced keratoconus with acute hydrops. Corneal topography also showed features consistent with keratoconus in his left eye. Fluorescein angiography and optical coherence tomography revealed choroidal neovascularization-associated subretinal hemorrhages and lacquer cracks in both eyes.</p> <p>Conclusion</p> <p>Keratoconus and choroidal neovascularization, possibly resulting from dysfunction of the epithelium and its basement membrane, can occur together in the same individual. This would suggest a possible connection in pathogenesis between these two conditions.</p