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Dive into the research topics where Tomohiro Takeda is active.

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Featured researches published by Tomohiro Takeda.


Allergy | 2011

Increase of coagulation potential in chronic spontaneous urticaria

Tomohiro Takeda; Yoshihiko Sakurai; Shunsuke Takahagi; Junko Kato; Koichi Yoshida; Akira Yoshioka; Michihiro Hide; Midori Shima

To cite this article: Takeda T, Sakurai Y, Takahagi S, Kato J, Yoshida K, Yoshioka A, Hide M, Shima M. Increase of coagulation potential in chronic spontaneous urticaria. Allergy 2011; 66: 428–433.


International Archives of Allergy and Immunology | 2008

Anaphylaxis to polyvinylpyrrolidone in povidone-iodine for impetigo contagiosum in a boy with atopic dermatitis.

Koichi Yoshida; Yoshihiko Sakurai; Shingo Kawahara; Tomohiro Takeda; Tomoaki Ishikawa; Tomohiko Murakami; Akira Yoshioka

Background: Povidone-iodine (PVP-I) is widely used in antiseptic agents. Immediate allergic reaction to PVP-I preparations is very rare and often overlooked, as it is difficult to diagnose. Polyvinylpyrrolidone (PVP) is thought to play a role in the underlying mechanism. We examined the usefulness of the histamine release test (HRT) for definite diagnosis of PVP allergy. Method: A 9-year-old boy with eosinophilia (1,500/µl) and elevated total IgE (1,376 IU/ml) was suspected clinically of having a PVP allergy, as he had anaphylaxis twice when he was administered a PVP-I solution for impetigo contagiosum. Skin prick tests (SPTs) were performed with a PVP-I solution, PVP (K30), gentamicin sulfate and 2 other medicines containing PVP. HRT was assessed using peripheral blood basophils. Results: SPTs to PVP-I solution, PVP-K30 and other medicines were all negative. Histamine release was observed on stimulation by PVP in the presence of autologous serum, although it was not observed in the absence of autologous serum. Conclusions: This observation was in line with the clinical findings that anaphylaxis had not developed despite the long use of PVP-I solution, but developed only when he received PVP-I solution treatment where basophils could contact PVP-I in the presence of serum, which was probably due to a broken skin and vessel condition. Furthermore, our results suggest the usefulness of HRT in the diagnosis of PVP allergy, and the possibility that negative SPT does not entirely rule out PVP allergy.


Blood Coagulation & Fibrinolysis | 2007

Heparin-induced inhibitory effects of a prothrombin complex concentrate on global tests of haemostasis

Masahiro Takeyama; Yoshihiko Sakurai; Midori Shima; Tomoko Matsumoto; Keiji Nogami; Ichiro Tanaka; Tomohiro Takeda; John C. Giddings; Akira Yoshioka

Prothrombin complex concentrates (PCC) have been used as bypassing agents for the treatment of haemophilia A patients with inhibitor as well as for replacement therapy in congenital and acquired deficiencies of vitamin-K-dependent clotting factors. The efficacy of PCC is variable, however, especially during long-term and high-dose use, and all currently available products of this nature contain heparin. We have examined the haemostatic properties of PCC using reconstituted whole blood made by mixing coagulation-factor-deficient plasma and washed blood cells. In rotation thromboelastometry (ROTEM), the recommended therapeutic dose of Proplex ST corrected the abnormal patterns. At higher concentrations, however, the ROTEM patterns regressed. In addition, specific assays of coagulation factors appeared unreliable in the presence of 2.5 U/ml Proplex ST; the abnormalities were corrected when protamine sulfate was added. The findings suggest that the presence of heparin in PCC might have a greater effect on global haemostasis. Careful attention to the anticoagulant effect as well as thrombogenicity of PCC is required. Monitoring therapy using such as ROTEM analysis could be highly informative.


Clinical & Developmental Immunology | 2014

Acquired Hemophilia A: A Frequently Overlooked Autoimmune Hemorrhagic Disorder

Yoshihiko Sakurai; Tomohiro Takeda

Acquired hemophilia A (AHA) is a rare hemorrhagic disease in which autoantibodies against coagulation factor VIII- (FVIII-) neutralizing antibodies (inhibitors) impair the intrinsic coagulation system. As the inhibitors developed in AHA are autoantibodies, the disease may have an autoimmune cause and is often associated with autoimmune disease. Although acute hemorrhage associated with AHA may be fatal and is costly to treat, AHA is often unrecognized or misdiagnosed. AHA should thus be considered in the differential diagnosis particularly in postpartum women and the elderly with bleeding tendency or prolonged activated partial thromboplastin time. Cross-mixing tests and measurement of FVIII-binding antibodies are useful to confirm AHA diagnosis. For treatment of acute hemorrhage, hemostatic therapy with bypassing agents should be provided. Unlike in congenital hemophilia A with inhibitors, in which immune tolerance induction therapy using repetitive infusions of high-dose FVIII concentrates is effective for inhibitor eradication, immune tolerance induction therapy has shown poor efficacy in treating AHA. Immunosuppressive treatment should thus be initiated to eradicate inhibitors as soon as the diagnosis of AHA is confirmed.


Blood Coagulation & Fibrinolysis | 2011

Expression of coagulation factors from murine induced pluripotent stem cell-derived liver cells

Shogo Kasuda; Kohei Tatsumi; Yoshihiko Sakurai; Junko Kato; Sanae Taminishi; Tomohiro Takeda; Kazuo Ohashi; Teruo Okano; Katsuhiko Hatake; Midori Shima

A protocol to differentiate liver cells from induced pluripotent stem (iPS) cells is being established. However, the ability of these differentiated iPS cells to express liver-specific proteins, such as coagulation cascade and related factors, has yet to be assessed. This study evaluated whether liver-like populations differentiated from murine iPS cells gain the ability to produce coagulation-related factors. Following differentiation of murine iPS cells into hematopoietic-like and liver-like embryoid bodies, we assessed gene expression profiles for coagulation-related markers, including fibrinogen, factors II, V, VII, VIII, IX, X, XI, XII, and XIIIβ, protein C, protein S, antithrombin, plasminogen, von Willebrand factor, and ADAMTS13 by real-time reverse transcription PCR. Liver-like embryoid bodies demonstrated strong expression levels of nearly all the coagulation-related genes assessed, compared with undifferentiated iPS cells and hematopoietic-like embryoid bodies. We also confirmed efficient translation and secretion of fibrinogen and albumin (hepatocyte-specific marker proteins) into the conditioned medium by these differentiated cells, suggesting successful differentiation of iPS cells into the liver lineage. These findings suggest that iPS cells can be differentiated into liver-like populations that express coagulation-related factors. Liver-like embryoid bodies may provide a source for cell-based therapies directed toward liver diseases, including coagulation factor deficiencies in the future.


International Journal of Hematology | 2007

Factor VIII-mediated global hemostasis in the absence of von Willebrand factor

Masahiro Takeyama; Shogo Kasuda; Yoshihiko Sakurai; Midori Shima; Tomohiro Takeda; Shoko Omura; Hiroyuki Naka; Akira Yoshioka

Although the efficacy of recombinant factor VIII (rFVIII) in the treatment of type 3 von Willebrand disease (VWD) has been reported, the mechanisms by which FVIII concentrates devoid of von Willebrand factor (VWF) induce improvements in hemostasis are poorly understood. To address the role of FVIII or intrinsic coagulation in the absence of VWF, we performed a hemostatic analysis. Blood samples were obtained before and after the administration of rFVIII to 2 patients with type 3 VWD. A rotating thromboelastometry assay was performed to examine global interactions in hemostasis. Studies of thrombin-and shear-induced platelet aggregation were also conducted to elucidate the effect on platelet activation. Furthermore, we assessed the rise in the thrombin-induced intracellular concentration of free calcium ([Ca2+]i). Addition of rFVIII to preinfusion blood in vitro corrected thromboelastometric parameters and thrombin-induced aggregation. In ex vivo studies, thromboelastometry analysis showed that rFVIII shortened the onset and progression of the coagulation process. Furthermore, rFVIII corrected low shear-induced and thrombin-induced platelet aggregation in platelet-rich plasma. In addition, rFVIII improved thrombin-induced [Ca2+]i flux in washed platelets. Our observations suggested that FVIII is incorporated into platelets to activate them, as well as to act directly in intrinsic coagulation in the absence of VWF. FVIII may play a critical role even in the absence of VWF.


Thrombosis and Haemostasis | 2009

Elevation of B cell-activating factor belonging to the tumour necrosis family family (BAFF) in haemophilia A patients with inhibitor

Tomohiro Takeda; Yoshihiko Sakurai; Kohei Tatsumi; Junko Kato; Shogo Kasuda; Akira Yoshioka; Midori Shima

Elevation of B cell-activating factor belonging to the tumour necrosis family family (BAFF) in haemophilia A patients with inhibitor -


Hematology Reviews | 2013

Repression of Factor VIII Inhibitor Development with Apoptotic Factor VIII-expressing Embryonic Stem Cells.

Yoshihiko Sakurai; Shogo Kasuda; Kohei Tatsumi; Tomohiro Takeda; Junko Kato; Atsushi Kubo; Midori Shima

Development of factor VIII (fVIII)-neutralizing antibodies, called inhibitors, is a challenging problem in the management of hemophilia A patients. We explored the possibility of pretreatment with apoptotic fVIII-expressing embryonic stem (ES) cells to prevent the development of fVIII inhibitors. Murine ES cells integrated with the human F8 gene were differentiated into embryoid bodies, dissociated to a single cell suspension, subjected to hypo-osmotic shock to induce apoptosis, and intraperitoneally injected into hemophilia A mice. Inhibitors were induced by periodic intraperitoneal injections of recombinant human fVIII (rhfVIII). In the groups in which intraperitoneal injections of rhfVIII began at 1-3 weeks after pretreatment, the titers of inhibitors were significantly lower after the third administration of rhfVIII compared with that in the control group in which apoptotic Ainv18 ES cells (without the human F8 gene) were used for pretreatment, and continued to show lower levels until the sixth administration of rhfVIII. These results suggest that pretreatment with apoptotic hfVIII-expressing ES cells might be promising for the prevention of fVIII inhibitor development in hemophilia A patients.


Case reports in pediatrics | 2012

Early-onset chronic inflammatory disease associated with maternal microchimerism.

Tomoaki Ishikawa; Yoshihiko Sakurai; Tomohiro Takeda; Hiroshi Suzuki

Maternal microchimerism (mMc) refers to the presence of a small population of cells originating from the mother. Whether mMc leads to autoimmune responses in children remains controversial. We describe here an 11-year-old boy with persistent fever and elevated levels of C-reactive protein from infancy onward. During infancy, the patient presented with high fever, skin rashes, and hepatic dysfunction. Careful examination including a liver biopsy failed to reveal the cause. At 4 years old, petechiae developed associated with thrombocytopenia and positive anti-dsDNA autoantibodies. Steroid pulse therapy was effective, but the effect of low-dose prednisone was insufficient. At age 9, an extensive differential diagnosis was considered especially for infantile onset autoinflammatory disorders but failed to make a definitive diagnosis. On admission, the patient exhibited short stature, hepatosplenomegaly, generalized superficial lymphadenopathy, and rashes. Laboratory findings revealed anemia, elevated levels of inflammation markers, and hypergammaglobulinemia. Serum complement levels were normal. Serum levels of IL-6 and B-cell activating factor were elevated. Viral infections were not identified. Although HLA typing revealed no noninherited maternal antigens in lymphocytes, female cells were demonstrated in the patients skin and lymph nodes, suggesting that maternal microchimerism might be involved in the pathogenesis of fever without source in infants.


Alcoholism: Clinical and Experimental Research | 2006

Inhibition of PAR4 Signaling Mediates Ethanol‐Induced Attenuation of Platelet Function In Vitro

Shogo Kasuda; Yoshihiko Sakurai; Midori Shima; Yoshifumi Morimura; Risa Kudo; Tomohiro Takeda; Akiko Ishitani; Akira Yoshioka; Katsuhiko Hatake

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Midori Shima

Nara Medical University

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Shogo Kasuda

Nara Medical University

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Junko Kato

Nara Medical University

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Atsushi Kubo

Nara Medical University

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