コンバラトキシンによる凝固亢進における単球由来組織因子陽性細胞外小胞の関与

Objectives: Convallatoxin (CNT) is a natural cardiac glycoside extracted from lily of the valley (Convallaria majalis). Although it is empirically known to cause blood coagulation disorders, the underlying mechanism remains unclear. CNT exerts cytotoxicity and increases tissue factor (TF) expression in endothelial cells. However, the direct action of CNT on blood coagulation remains unclear. Therefore, herein, we investigated the effects of CNT on whole blood coagulation system and TF expression in monocytes. Methods: Blood samples were collected from healthy volunteers to measure plasma thrombin–antithrombin complex (TAT) concentration using ELISA and to perform rotational thromboelastometry (ROTEM) and whole-blood extracellular vesicle (EV)-associated TF (EV-TF) analysis. The effects of CNT were also investigated using the monocytic human cell line THP-1. Quantitative real-time PCR and western blotting were performed, and PD98059, a mitogen-activated protein kinase (MAPK) inhibitor, was used to elucidate the action mechanism of CNT-mediated TF production. Results: CNT treatment increased EV-TF activity, shortened the whole blood clotting time in rotational thromboelastometry analysis, and increased TAT levels, which is an index of thrombin generation. Furthermore, CNT increased TF mRNA expression in THP-1 cells and EV-TF activity in the cell culture supernatant. Therefore, CNT may induce a hypercoagulable state with thrombin generation, in which elevated EV-TF activity derived from monocytes might be involved. These procoagulant effects of CNT were reversed by PD98059, suggesting that CNT-induced TF production in monocytes might be mediated by the MAPK pathway. Conclusions: The findings of the present study have further clarified the procoagulant properties of CNT.本文は発行元が定める公開猶予期間終了後に公開

トクシマ コウエン トクシマ チュウオウ コウエン ノ ゾウエン セッケイ ニツイテ : ヒビヤ コウエン オヨビ ザイファースドルフジョウ トノ ヒカク

Tokushima Park (originally named Tokushima Central Park) is the Japan’s second western-style park that was opened in 1906. We investigated landscape architecture of Tokushima Park based on a blueprint made in 1905 to understand its purpose and function of the park, and compared with Hibiya Park that is the Japan’s first western-style park. Tokushima Park consisted of five areas. The central area included Mt. Shiroyama (Castle Mountain), and primeval forest was protected without allowing to make a big building within the area. A commercial museum, an athletic field, and a botanical garden and a library were placed in the southern, western and eastern areas respectively, so that each area was designed to exhibit each function. Tokushima Park and Hibiya Park were designed by the same two persons Seiroku Honda and Takanori Hongo. The two parks were equipped with a wide road, an athletic field, a botanical garden and so on, and these facilities were adopted to the park made since them. Because Seiroku Honda adopted three design drawings of German parks from the book Gärtnerisches Planzeichnen into a blueprint of Hibiya Park, we investigated the book to ascertain whether any design drawing was also used in Tokushima Park. We found that Seifersdorf Castle, the castle of count Brühl that was built at Seifersdorf in Germany in 13th century, is similar to the southern area of Tokushima Park

Development of new optical imaging systems of oxygen metabolism and simultaneous measurement in hemodynamic changes using awake mice.

Background:PET allows the measurement of CBF, CBV and CMRO2 in human and plays an important role in the diagnosis of pathologic conditions and clinical research. On the other hand, in animal studies, there is no optical imaging system for evaluating changes in CBF and CBV, and oxygen metabolism, from the same brain area under awake condition.New method:In the present study, we developed a simultaneous measurement system of LSI and IOSI, which was verified by LDF. Moreover, to evaluate oxygen metabolism, FAI was performed from the same brain area as LSI and IOSI measurements.Results:The change in CBF according to LSI was correlated with that by LDF. Similarly, the change in CBV obtained by IOSI was also correlated with RBC concentration change measured by LDF. The change in oxygen metabolism by FAI was associated with that in CBF obtained by LSI, although the change in CBF was greater than that in oxygen metabolism.Comparison with existing method(s): We revealed that the relationship between oxygen metabolism and CBF as measured by our system was in good agreement with the relationship between CMRO2 and CBF in human PET studies.Conclusions:Our measurement system of CBF, CBV and oxygen metabolism is not only useful for studying neurovascular coupling, but also easily corroborates human PET studies

Generation of functional liver sinusoidal endothelial-like cells from human bone marrow-derived mesenchymal stem cells

Introduction: Liver sinusoidal endothelial cells (LSECs) are specialized vascular endothelial cells that play an important role in the maintenance of biological homeostasis. However, the lack of versatile human LSECs has hindered research on LSECs and development of medical technologies for liver diseases including hemophilia A. In this study, we developed a technique to induce LSEC differentiation from human bone marrow-derived mesenchymal stem cells (BM-MSCs). Methods: To induce LSECs from human BM-MSCs, cytokines and chemical compounds associated with signaling implicated in LSEC differentiation and liver development were screened. Then LSEC-related genes and proteins expression in the differentiated cells were analyzed by qPCR and flow cytometry analysis, respectively. LSEC-related functions of the differentiated cells were also examined. Results: We found that the gene expression of LSEC markers, such as LYVE1, was considerably increased by culturing human BM-MSCs with bone morphogenetic protein 4, fibroblast growth factor 8b, transforming growth factor-β signal inhibitor, and cyclic AMP. Furthermore, the differentiated cells expressed LSEC marker proteins and clearly demonstrated LSEC-specific functions, such as the uptake of hyaluronic acid. Conclusions: Our result indicate that the functional LSEC-like cells were successfully generated from human BM-MSCs using our established protocol

Inhibitory effects of caffeine on gustatory plasticity in the nematode Caenorhabditis elegans.

The effects of caffeine on salt chemotaxis learning were investigated using the nematode Caenorhabditis elegans. To estimate the degree of salt chemotaxis learning, nematodes were placed in a mixed solution of NaCl and caffeine, and then the chemotaxis index of NaCl was obtained from the nematodes placed on agar medium after pre-exposure to caffeine concentrations of 0.01, 0.1, 0.3, and 1.0%. Locomotor activity and preference behavior for caffeine were also estimated under these caffeine conditions. Nematodes pre-exposed to 0.3% caffeine showed inhibition of salt chemotaxis learning. Additional experiments indicated that nematodes showed a preference response to the middle concentration of caffeine (0.1%), with preference behavior declining in the 0.3% caffeine condition. Stable locomotor activity was observed under 0.01-0.3% caffeine conditions. These results suggest that salt chemotaxis learning with 0.3% caffeine is useful for investigating the effects of caffeine on learning in nematodes

Hemostatic function to regulate perioperative bleeding in patients undergoing spinal surgery: A prospective observational study.

Although bleeding is a common complication of surgery, routine laboratory tests have been demonstrated to have a low ability to predict perioperative bleeding. Better understanding of hemostatic function during surgery would lead to identification of high-risk patients for bleeding. Here, we aimed to elucidate hemostatic mechanisms to determine perioperative bleeding. We prospectively enrolled 104 patients undergoing cervical spinal surgery without bleeding diathesis. Blood sampling was performed just before the operation. Volumes of perioperative blood loss were compared with the results of detailed laboratory tests assessing primary hemostasis, secondary hemostasis, and fibrinolysis. Platelet aggregations induced by several agonists correlated with each other, and only two latent factors determined inter-individual difference. Platelet aggregability independently determined perioperative bleeding. We also identified low levels of plasminogen-activator inhibitor-1 (PAI-1) and α2-plasmin inhibitor to be independent risk factors for intraoperative and postoperative bleeding, respectively. Most important independent factor to determine postoperative bleeding was body weight. Of note, obese patients with low levels of PAI-1 became high-risk patients for bleeding during surgery. Our data suggest that bleeding after surgical procedure may be influenced by inter-individual differences of hemostatic function including platelet function and fibrinolysis, even in the patients without bleeding diathesis