465 research outputs found

    Roosting ecology of endangered plant‐roosting bats on Okinawa Island: Implications for bat‐friendly forestry practices

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    Roosting information is crucial to guiding bat conservation and bat-friendly forestry practices. The Ryukyu tube-nosed bat Murina ryukyuana (Endangered) and Yanbaru whiskered bat Myotis yanbarensis (Critically Endangered) are forest-dwelling bats endemic to the central Ryukyu Archipelago, Japan. Despite their threatened status, little is known about the roosting ecology of these species and the characteristics of natural maternity roosts are unknown. To inform sustainable forestry practices and conservation management, we radio-tracked day roosts of both species in the subtropical forests of Okinawa's Kunigami Village District. We compared roost and roost site characteristics statistically between M. ryukyuana nonmaternity roosts (males or nonreproductive females), maternity roosts, and all M. yanbarensis roosts. Generalized linear models were used to investigate roost site selection by M. ryukyuana irrespective of sex and age class. Lastly, we compiled data on phenology from this and prior studies. Nonreproductive M. ryukyuana roosted alone and primarily in understory foliage. Murina ryukyuana maternity roosts were limited to stands >50 years old, and ~60% were in foliage. Myotis yanbarensis roosted almost entirely in cavities along gulch bottoms and only in stands >70 years old (~1/3 of Kunigami's total forest area). Murina ryukyuana maternity roosts were higher (4.3 ± 0.6 m) than conspecific nonmaternity roosts (2.3 ± 0.5 m; p <.001) and M. yanbarensis roosts (2.7 ± 0.5 m; not significant). Model results were inconclusive. Both species appear to be obligate plant roosters throughout their life cycle, but the less flexible roosting preferences of M. yanbarensis may explain its striking rarity. To conserve these threatened bats, we recommend the following forestry practices: (a) reduce clearing of understory vegetation, (b) refrain from removing trees along streams, (c) promote greater tree cavity densities by protecting old-growth forests and retaining snags, and (d) refrain from removing trees or understory between April and July, while bats are pupping.コウモリのねぐらに関する生態学的な情報はコウモリの保全とそれを考慮する森林の施業のために重要である。リュウキュウテングコウモリMurina ryukyuana(絶滅危惧)とヤンバルホオヒゲコウモリMyotis yanbarensis(絶滅寸前)は森林性コウモリで、日本の琉球列島中部における固有種である。絶滅の恐れがある種にもかかわらず、これらの種のねぐらに関する生態については情報が不足しており、自然条件下における母子集団のねぐらの特徴は明らかになっていない。持続可能な森林施業と保全に関わる情報を提供するために、沖縄島国頭村における亜熱帯林で両種の昼間のねぐらの場所や特徴を、ラジオテレメトリー法によって個体を追跡することによって調査した。リュウキュウテングコウモリの非母子集団ねぐら(雄または非繁殖雌)、母子集団ねぐら、及び全てのヤンバルホオヒゲコウモリのねぐらの間で、ねぐらとねぐらの場所の特徴を統計的に比較した。一般化線形モデルを用いて、性別や年齢階級を考慮しない条件でリュウキュウテングコウモリによるねぐら場所の選好性を調査した。最後に、本研究と先行研究から、ねぐらに関わるフェノロジーに関するデータを収集・整理した。非生殖のリュウキュウテングコウモリは単独で、主に下層植生の葉をねぐらとして利用した。リュウキュウテングコウモリの母子集団のねぐらとしての利用は林齢50年以上の林分に限定され、約60%が葉であった。ヤンバルホオヒゲコウモリはほぼ完全に谷底の樹洞をねぐらとして利用し、ねぐらの形成は林齢70年以上の林分に限られていた(国頭村における森林面積の約1/3)。リュウキュウテングコウモリの母子集団ねぐらは同種の非母子集団ねぐら(2.3 ± 0.5 m; p < .001)とヤンバルホオヒゲコウモリのねぐら(2.7 ± 0.5 m; not significant)より高い位置にあった(4.3 ± 0.6 m)。モデルによる推定結果は決定的ではなかった。両種はライフサイクルの間ずっと偏性的な植物性コウモリであるようだが、ヤンバルホオヒゲコウモリの選好は柔軟性が低く、このことが本種の際だった希少性を説明する可能性がある。これらの絶滅危惧種であるコウモリを保全するためには、以下の森林施業が提案できる:(a)下層植生の除去を少なくすること、(b)渓流沿いの樹木の伐採を控えること、(c)高林齢の森林を保存し、枯死木も除去せず、樹洞の密度を確保すること、(d)コウモリが子育てしている時期である4月〜7月の間に、樹木と下層植生の除去を控えることである

    Functional Effects of Endogenous Bradykinin in Congestive Heart Failure

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    AbstractObjectives. The purpose of this study was to determine the level and functional effects of endogenous bradykinin in congestive heart failure (CHF).Background. There is experimental evidence that bradykinin is increased in several cardiac disease states. However, it is unknown whether plasma levels of bradykinin are elevated in CHF. Further, the cardiac and vascular responses to bradykinin in CHF are unclear.Methods. The circulating levels of bradykinin and the effects of endogenous bradykinin were assessed in eight instrumented, conscious dogs both before and after pacing-induced CHF.Results. Before CHF, the plasma bradykinin level was 53.1 ± 12.4 pg/ml. Blocking endogenous bradykinin with HOE-140 (0.3 mg/kg), a specific bradykinin B2-receptor antagonist, produced no significant alterations in heart rate, left ventricular (LV) end-systolic pressure (Pes), total systemic resistance (TSR), the time constant of LV relaxation (tau) or the maximal rate of LV filling (dV/dtmax). However, coronary blood flow was significantly reduced (p < 0.05). LV contractile performance measured by the slopes of pressure–volume relations was unaffected. After induction of CHF, the plasma bradykinin level increased to 234.2 ± 19.4 pg/ml (p < 0.05). Blocking endogenous bradykinin with HOE-140 reduced coronary blood flow and produced significant increases in Pesand TSR, prolonged tau, decreased dV/dtmaxand elevated minimal LV pressure and mean left atrial pressure. Furthermore, the slopes of pressure–volume relations (p < 0.05) were decreased, indicating depressed contractility with HOE-140 after CHF.Conclusions. Before CHF, endogenous bradykinin results in coronary dilation but has no effect on systemic arterial vasodilation or cardiac performance. After CHF, endogenous bradykinin is significantly increased and, acting through B2-receptors, produces coronary and arterial vasodilation and improves LV relaxation and contractile performance. Thus, endogenous bradykinin may play an important role in preserving cardiovascular function in CHF

    Prognostic Value of Left Ventricular Diastolic Dysfunction in Patients Undergoing Cardiac Catheterization for Coronary Artery Disease

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    We hypothesized that left ventricular (LV) diastolic dysfunction assessed by cardiac catheterization may be associated with increased risk for cardiovascular events. To test the hypothesis, we assessed diastolic function by cardiac catheterization (relaxation time constant (Tau) and end-diastolic pressure (EDP)) as well as Doppler echocardiography (early diastolic mitral annular velocity (e′) and a ratio of early diastolic mitral inflow to annular velocities (E/e′)) in 222 consecutive patients undergoing cardiac catheterization for coronary artery disease (CAD). During a followup of 1364 ± 628 days, 5 cardiac deaths and 20 unscheduled cardiovascular hospitalizations were observed. Among LV diastolic function indices, Tau > 48 ms and e′ < 5.8 cm/s were each significantly associated with lower rate of survival free of cardiovascular hospitalization. Even after adjustment for potential confounders (traditional cardiovascular risk factors, the severity of CAD, and cardiovascular medications), the predictive value of Tau > 48 ms and e′ < 5.8 cm/s remained significant. No predictive value was observed in EDP, E/e′, or LV ejection fraction. In conclusion, LV diastolic dysfunction, particularly impaired LV relaxation assessed by both cardiac catheterization and Doppler echocardiography, is independently associated with increased risk for cardiac death or cardiovascular hospitalization in patients with known or suspected CAD

    Specification of osteoblast cell fate by canonical Wnt signaling requires Bmp2

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    Enhanced BMP or canonical Wnt (cWnt) signaling are therapeutic strategies employed to enhance bone formation and fracture repair, but the mechanisms each pathway utilizes to specify cell fate of bone-forming osteoblasts remain poorly understood. Among all BMPs expressed in bone, we find that singular deficiency of Bmp2 blocks the ability of cWnt signaling to specify osteoblasts from limb bud or bone marrow progenitors. When exposed to cWnts, Bmp2-deficient cells fail to progress through the Runx2/Osx1 checkpoint and thus do not upregulate multiple genes controlling mineral metabolism in osteoblasts. Cells lacking Bmp2 after induction of Osx1 differentiate normally in response to cWnts, suggesting that pre-Osx1(+) osteoprogenitors are an essential source and a target of BMP2. Our analysis furthermore reveals Grainyhead-like 3 (Grhl3) as a transcription factor in the osteoblast gene regulatory network induced during bone development and bone repair, which acts upstream of Osx1 in a BMP2-dependent manner. The Runx2/Osx1 transition therefore receives crucial regulatory inputs from BMP2 that are not compensated for by cWnt signaling, and this is mediated at least in part by induction and activation of Grhl3.National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIH-NIAMS)Harvard Sch Dent Med, Dept Dev Biol, 188 Longwood Ave, Boston, MA 02115 USASaitama Med Univ, Res Ctr Genom Med, Div Pathophysiol, 1397-1 Yamane, Hidaka, Saitama 3501241, JapanUniv Fed Sao Paulo, Inst Ciencia & Tecnol, Rua Talim 330, BR-12231280 Sao Jose Dos Campos, SP, BrazilUniversidade Federal de São Paulo, Rua Talim, 330, São José dos Campos, São Paulo, CEP 12231-280, BrazilNIH-NIAMS: R01 AR055904Web of Scienc

    哺乳類プロテアソームの細胞内局在を制御する新規因子の探索と動作機構の解明

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    学位の種別: 課程博士審査委員会委員 : (主査)東京大学教授 村田 茂穂, 東京大学教授 後藤 由季子, 東京大学教授 一條 秀憲, 東京大学教授 楠原 洋之, 東京大学講師 福山 征光University of Tokyo(東京大学

    Pulmonary venous occlusion and death in pulmonary arterial hypertension: survival analyses using radiographic surrogates

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    BACKGROUND: Recent studies find that a considerable number of patients with pulmonary arterial hypertension (PAH) develop fibrous obstruction of the pulmonary veins. Such obstruction more commonly accompanies connective tissue disorder (CTD)-associated PAH than idiopathic PAH. However, few researchers have gauged the risk of death involving obstruction of the pulmonary veins. METHODS: Thirty-seven patients with PAH were enrolled (18 patients, idiopathic PAH; 19 patients, CTD-associated PAH). The patients were 49 ± 18 years and had a World Health Organization functional class of 3.2 ± 0.6. Thickening of the interlobular septa, centrilobular ground-glass attenuation, and mediastinal adenopathy were surrogates for obstruction of the pulmonary veins, and were detected by a 16-row multidetector computed tomography scanner. RESULTS: The follow-up period was 714 ± 552 days. Fifteen deaths occurred. Thickening of the interlobular septa, centrilobular ground-glass attenuation, and mediastinal adenopathy were found in 37.8%, 24.3%, and 16.2% of patients, respectively. Cox proportional hazard analysis revealed an increased risk of death with each radiographic surrogate (mediastinal adenopathy: p < 0.0001, hazard ratio = 13.9; thickening of interlobular septa: p < 0.001, hazard ratio = 12.0; ground-glass attenuation: p = 0.02, hazard ratio = 3.7). The statistical significance of these relationships was independent of the cause of PAH and plasma concentration of brain natriuretic peptide. CONCLUSIONS: The results of this study imply that obstruction of the pulmonary veins is associated with an increased risk of death in patients with PAH

    プラスチック ソイル コンクリート ノ ケンキュウ 3 タイキュウセイ ニ ツイテ リンガク ブモン

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    プラスチック・ソイルコノクリートの耐久性を検討するに当って, 治山砂防の現場における環境を考慮すれば気象作用に対する抵抗性が一番大きな要因となることが考えられ, 本研究ではこの点から凍結融解試験を行なうことによって, 所要の目的を果せるように努めた。その結果以下の事項が認められた。すなわち, 1) 凍結融解試験の方法によって, 供試体の耐久性にちがった型の結果が生じること。本実験では, 空気中での凍結融解試験と, 水中でのそれとでは, 後者の方がはるかに条件がきびしく, 動弾性係数の低下率が大きかった。2) 動弾性係数は, 供試体の使用水量が多い程低下率が大きく, セメント使用量が小なほど低下率が大となった。(図-5. 6. 7)3) 土の種類によっても動弾性低下率に明らかに差が認められ, ひいては, 耐久性指数にもその影響がおよび, 北白川の方が布志名よりも耐久性では優れているといえる。4) 耐久性指数は, 使用セメント量が大なほど増大し, 使用水量が大なほど減少する(図-8)5) 動弾性係数と圧縮強度との関係は, 供試材料ごとにある曲線関係が成り立つことが認められる。(図-9)The auther have done several investigation for durability of plastic soil concrete, by making use of soil, as shown in Fig. 1 and Table 1,that is, the granite origin soil from Shigaraki in Shiga prefecture and Kitashirakawa in Kyoto prefecture, the lower Pleistcene origin soil from Kamigamo in Kyoto prefecture and the Tertiary origin soil from Fushina in Shimane prefecture. The results are summerized as follows; 1) Within the range of this report, the reduction rate of dynamic modulus of elasticity by the freezing and thawing test for the specimens in the water are greater than by the freezing and thawing test in the air. 2) For the dynamic modulus of elasticity, the more water content in specimens, the more reduction rate of dynamic modulus, and the more cement content in specimens, the less reduction rate of dynamic modulus of elasticity. (Fig. 5,6,and 7) 3) It is recognized that the reduction rate of dynamic modulus are distinctly difference by the soil type. Consequently, it is recognized that the durability of Kitashirakawa specimens are superior to that of Fushina specimens. 4) The more cement content in specimens, the more increase the durability factor, and the more water content in specimens, the more decrease the durability factor. (Fig. 8) 5) It is recognized that, within the range this report, some semi-logarithmic curves are drawn with each soil types for the relation between the dynamic modulus of elasticity and compressive strength of plastic soil concrete. (Fig. 9

    Thymoproteasomes produce unique peptide motifs for positive selection of CD8+ T cells

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    Positive selection in the thymus provides low-affinity T-cell receptor (TCR) engagement to support the development of potentially useful self-major histocompatibility complex class I (MHC-I)-restricted T cells. Optimal positive selection of CD8+ T cells requires cortical thymic epithelial cells that express β5t-containing thymoproteasomes (tCPs). However, how tCPs govern positive selection is unclear. Here we show that the tCPs produce unique cleavage motifs in digested peptides and in MHC-I-associated peptides. Interestingly, MHC-I-associated peptides carrying these tCP-dependent motifs are enriched with low-affinity TCR ligands that efficiently induce the positive selection of functionally competent CD8+ T cells in antigen-specific TCR-transgenic models. These results suggest that tCPs contribute to the positive selection of CD8+ T cells by preferentially producing low-affinity TCR ligand peptides

    Comparison of Hemorrhagic Risk between Prasugrel and Clopidogrel : a Retrospective Study using Adverse Drug Event Reporting Databases

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    Background: Prasugrel inhibits platelet aggregation more potently and exerts therapeutic action faster than clopidogrel. In the global phase III trial conducted in Western and South American countries that excluded Asian countries, prasugrel reduced ischemic events but increased hemorrhagic risk compared with clopidogrel in patients with acute coronary syndrome scheduled for percutaneous coronary intervention. In the Japanese phase III trial for similar patients, the efficacy of prasugrel compared with clopidogrel was comparable to the global trial, but the safety could not be confirmed because of an insufficient number of patients. Furthermore, given the strict enrollment criteria, the results of these trials may not be applicable to routine clinical practice. Accordingly, we compared the hemorrhagic risk of prasugrel and clopidogrel in real-world settings by analyzing adverse drug event reports in post-marketing stages provided by the Japanese regulatory authorities and the U.S. Food and Drug Administration (FDA). Methods: We analyzed a total of 3,970 reports for prasugrel (n = 518) or clopidogrel (n = 3,452) between 2014 and 2017 in the Japanese Adverse Drug Event Report (JADER) and a total of 91,914 reports for either prasugrel (n = 5,992) or clopidogrel (n = 85,922) between 2009 and 2019 in the FDA Adverse Event Reporting System (FAERS). Results: In JADER and FAERS, prasugrel was more frequently and significantly associated with hemorrhagic event reports than clopidogrel. After adjustment for known confounders including age, sex, and concomitant medications (aspirin, anticoagulants, and proton pump inhibitors), the hemorrhagic risk of prasugrel compared with clopidogrel remained significant (adjusted reporting odds ratios [95% CI] for total, intracranial, and gastrointestinal hemorrhagic events = 2.42 [1.97-2.96], 2.45 [1.85-3.24], and 2.27 [1.73-2.97] in JADER, and 2.21 [2.09-2.34], 1.21 [1.09-1.33], and 1.41 [1.29-1.54] in FAERS). Conclusions: The hemorrhagic risk was found to be greater with prasugrel than clopidogrel in real-world patients, including Japanese patients

    Lack of Inertia Force of Late Systolic Aortic Flow Is a Cause of Left Ventricular Isolated Diastolic Dysfunction in Patients With Coronary Artery Disease

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    ObjectivesWe investigated whether a lack of inertia force of late systolic aortic flow and/or apical asynergy provoke early diastolic dysfunction in patients with coronary artery disease (CAD).BackgroundLeft ventricular (LV) isolated diastolic dysfunction is a well-recognized cause of heart failure.MethodsWe evaluated LV apical wall motion and obtained left ventricular ejection fraction (LVEF) by left ventriculography in 101 patients who underwent cardiac catheterization to assess CAD. We also computed the LV relaxation time constant (Tp) and the inertia force of late systolic aortic flow from the LV pressure (P)–first derivative of left ventricular pressure (dP/dt) relation. Using color Doppler echocardiography, we measured the propagation velocity of LV early diastolic filling flow (Vp). Patients with LVEF ≥50% (preserved systolic function [PSF], n = 83) were divided into 2 subgroups: patients with inertia force (n = 53) and without inertia force (n = 30). No patient with systolic dysfunction (SDF) (LVEF <50%) had inertia force (n = 18).ResultsThe Tp was significantly longer in patients with SDF (85.7 ± 21.0 ms) and with PSF without inertia force (81.1 ± 23.6 ms) than in those with PSF with inertia force (66.3 ± 12.8 ms) (p< 0.001). The Vp was significantly less in the former 2 groups than in the last group. In patients with PSF, LV apical wall motion abnormality was less frequently observed in those with inertia force than in those without (p < 0.0001).ConclusionsAn absence of inertia force in patients with PSF is one of the causes of isolated diastolic dysfunction in patients with CAD. Normal LV apical wall motion is substantial enough to give inertia to late systolic aortic flow
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