Publications by authors named "Takashi Shirakawa"

Objective: The elasticity of the aortic wall varies depending on age, vessel location, and the presence of aortic diseases. Noninvasive measurement will be a powerful tool to understand the mechanical state of the aorta in a living human body. This study aimed to determine the elastic modulus of the aorta using computed tomography images.

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A 49-year-old man was admitted to our hospital because of intermittent claudication and refractory hypertension 10 years after surgery to Stanford type A acute aortic dissection. He underwent total arch replacement with an elephant trunk of 22 mm in diameter. Transesophageal echocardiography revealed that distal end of the elephant trunk was stenosed.

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, which causes varnish spots on lettuce and seriously damages lettuce production during the summer season in the highland areas of Japan (e.g., Nagano and Iwate prefectures) was isolated.

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Surgical simulation devices can be helpful and cost-effective adjuncts to on-the-job training. In this tutorial we present our method for creating an aortic stenosis model with realistically fragile and crushable calcifications, using modern 3D-printing techniques.  The model can be used for training and surgical simulation and is an effective aid to learning for young cardiovascular surgeons.

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Determining the complex geometry of mitral valve prolapse is often difficult. We constructed 3D models of six prolapsed mitral valves for surgical assessment, and evaluated how accurately the models could replicate individual valve dimensions. 3D polygon data were constructed based on an original segmentation method for computed tomography images.

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Stent grafting for complex aortic anatomy remains a challenge. In particular, stent graft collapse (i.e.

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Celiac artery compression syndrome(CACS)is a rare disorder characterized by postprandial intestinal angina caused by insufficient blood supply to the gastrointestinal organs. In this syndrome, the root of the celiac artery is compressed and narrowed by the median arcuate ligament of the diaphragm during expiration, sometimes causing difficulties in trans-arterial intervention. We report here a case that trans-hepatic arterial intervention was able to performed by splenic bypass.

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We present a case of a double-chambered right ventricle in adulthood, in which we tried a detailed morphological assessment and preoperative simulation using 3-dimensional (3D) heart models for improved surgical planning. Polygonal object data for the heart were constructed from computed tomography images of this patient, and transferred to a desktop 3D printer to print out models in actual size. Medical staff completed all of the work processes.

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Background: Small molecules classified as haptens are generally measured by competitive immunoassay, which is theoretically inferior to noncompetitive sandwich immunoassay in terms of sensitivity and specificity. We created a method for developing sandwich immunoassays to measure haptens on the basis of antimetatype antibodies.

Methods: We generated antimetatype monoclonal antibodies against a hapten-antibody immunocomplex using an ex vivo antibody development system, the Autonomously Diversifying Library (ADLib) system.

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Background: The factors regulating particle size of remnant lipoproteins (RLPs) in type 2 diabetes (T2DM) and metabolic syndrome (MetS) cases have not been well elucidated.

Methods: T2DM, MetS and healthy controls with and without a fatty liver were studied. Remnant lipoprotein (RLP)-cholesterol (RLP-C) and RLP-triglyceride (RLP-TG), small dense LDL-cholesterol (sdLDL-C), lipoprotein lipase (LPL), hepatic triglyceride lipase (HTGL) and adiponectin concentrations were measured in the fasting pre-heparin plasma.

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Background: A comparison of post-heparin and pre-heparin plasma lipoprotein lipase (LPL) and hepatic triglyceride lipase (HTGL) on the metabolism of remnant lipoproteins (RLPs) has not been reported yet.

Methods: Healthy volunteers were injected with heparin for LPL and HTGL determination in the fasting (8:00) and postprandial (20:00) plasma on the same day. Plasma total cholesterol (TC), triglycerides (TG), LDL-C, HDL-C, small dense LDL (sdLDL)-C, remnant lipoprotein (RLP)-C, RLP-TG, the RLP-TG/RLP-C ratio, adiponectin and apoCIII were measured.

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Chromeceptin is a synthetic small molecule that inhibits insulin-induced adipogenesis of 3T3-L1 cells and impairs the function of IGF2 (insulin-like growth factor 2). The molecular target of this benzochromene derivative is MFP-2 (multifunctional protein 2). The interaction between chromeceptin and MFP-2 activates STAT6 (signal transducer and activator of transcription 6), which subsequently induces IGF inhibitory genes.

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To evaluate the efficacy of S-1 for Stage IV gastric cancer, we retrospectively examined 124 patients with Stage IV gastric cancer. We classified patients into two groups based on the presence or absence of S-1 administration: the S-1 therapy group (n= 56) and the non-S-1 therapy group (n=68). Basically, patients received S-1 orally at 40 mg per square meter of body surface area twice daily for 4 weeks, followed by 2 weeks without chemotherapy.

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Fatostatin, a recently discovered small molecule that inhibits activation of sterol regulatory element-binding protein (SREBP), blocks biosynthesis and accumulation of fat in obese mice. We synthesized and evaluated a series of fatostatin derivatives. Our structure-activity relationships led to the identification of N-(4-(2-(2-propylpyridin-4-yl)thiazol-4-yl)phenyl)methanesulfonamide (24, FGH10019) as the most potent druglike molecule among the analogues tested.

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Three anti-H5 influenza virus monoclonal antibody (mAb) clones, IFH5-26, IFH5-115 and IFH5-136, were obtained by immunising a BALB/C mouse with inactivated A/duck/Hokkaido/Vac-1/04 (H5N1). These mAbs were found to recognise specifically the haemagglutinin (HA) epitope of the influenza H5 subtypes by western blotting with recombinant HAs; however, these mAbs have no neutralising activity for A/duck/Hokkaido/84/02 (H5N3) or A/Puerto Ric/8/34 (H1N1). Each epitope of these mAbs was a conformational epitope that was formed from the regions located between 46 to 60 amino acids (aa) and 312 to 322 aa for IFH5-115, from 101 to 113 aa and 268 to 273 aa for IFH5-136 and from 61 to 80 aa and 290 to 300 aa for IFH5-26.

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Aurilide is a potent cytotoxic marine natural product that induces apoptosis in cultured human cells at the picomolar to nanomolar range; however, its mechanism of action has been unknown. Results of the present study showed that aurilide selectively binds to prohibitin 1 (PHB1) in the mitochondria, activating the proteolytic processing of optic atrophy 1 (OPA1) and resulting in mitochondria-induced apoptosis. The mechanism of aurilide cytotoxicity suggests that PHB1 is an apoptosis-regulating protein amenable to modulation by small molecules.

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Signal transducer and activator of transcription 6 (STAT6), which plays a critical role in immune responses, is activated by interleukin-4 (IL-4). Activity of STAT family members is regulated primarily by tyrosine phosphorylations and possibly also by serine phosphorylations. Here, we report a previously undescribed serine phosphorylation of STAT6, which is activated by cell stress or by the pro-inflammatory cytokine, interleukin-1β (IL-1β).

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A 21-year-old woman developed psychiatric symptoms, progressive unresponsiveness, generalized seizures, severe dyskinesia, marked fluctuation of blood pressure, and hypersalivation after a flu-like episode. Anti-glutamate receptor (GluR)ε2 and anti-N-methyl-D-aspartate receptor (NMDAR) antibodies were positive in both her serum and CSF. After she recovered five months later she underwent surgery to remove a right ovarian teratoma.

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We report on a patient with obstructive jaundice caused by recurrence of gastric carcinoma in the wall of an extrahepatic bile duct more than 5 years after gastrectomy who was treated with pancreaticoduodenectomy. Histopathologic examination of the surgically resected specimen revealed a poorly differentiated adenocarcinoma with focal signet ring cells in the wall of the common bile duct which was histologically similar to the primary gastric carcinoma. To confirm the diagnosis, immunohistochemical staining was performed with antibodies against cytokeratins (CK7, CK20) and mucin peptide core antigens (MUC5AC, MUC6, MUC2).

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Although a number of genomic and biochemical technologies are now used to elucidate the mechanisms of action of bioactive small molecules, affinity-based isolation of molecular targets is a classic, but still powerful, approach. This review highlights recent cases where biochemical isolation of target proteins of bioactive small molecules highlighted general strategies for a successful isolation and identification of molecular targets. This review is intended to be both an update on the most recent findings for those already active in the field of forward chemical genetics and a guide for scientists entering this burgeoning field.

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Paclitaxel (PTX), which is used for ovarian cancer, lung cancer, breast cancer and gastric cancer, is administered at a dose of 210 mg/m(2) once every three weeks. However, WHO grade 3-4 hematological and non-hematological toxicity occurred frequently in this manner. In recent studies about ovarian cancer and lung cancer, a schedule in which PTX was given weekly could have the same or better efficacy, with fewer side effects.

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Object: Boron neutron capture therapy (BNCT) requires selective delivery of a high concentration of boron-10 ((10)B) to tumor tissue. To improve a drug delivery in BNCT, we devised transferrin-conjugated polyethylene-glycol liposome encapsulating sodium borocaptate (TF-PEG-BSH).

Methods: (10)B concentrations of U87Delta human glioma cells from three boron delivery systems (BDS) (bare BSH, PEG-BSH, and TF-PEG-BSH) were analyzed in vitro by use of inductively coupled plasma-atomic emission spectrometry (ICP-AES).

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Background: Gastric cancers in young adults are thought to be associated with risk factors that include Helicobacter pylori infection and genetic polymorphism. The objective of this study was to elucidate the roles of these risk factors in patients younger than 40 years by analyzing clinicopathological data and H. pylori infection, and using molecular epidemiologic techniques.

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Background: Cytotoxic drug-induced emesis is the side effect most feared by cancer patients. The Acute emesis has become well controlled by the emergence appearance of 5-HT3 receptor antagonist, but control of delayed emesis (DE) is insufficient. The mechanism of DE is different from acute emesis,and the existence of a mediator different from serotonin is contemplated.

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