MBF Measurements Using 82Rb PET

82Rb PET has high diagnostic accuracy however, relative perfusion imaging has its limitations, especially in multivessel disease 13 . Parkash et al. 31 reported reduced MBF in segments without obvious perfusion defects by relative perfusion image in patients with multivessel coronary disease. Yoshinaga et al. 21 reported that coronary flow reserve was reduced in remote segments without coronary artery stenosis in patients with coronary artery disease. These two studies established the clinical...

Efficacy of S5751 in Allergic Diseases in Animal Models

First of all, we evaluated the effect of S-5751 on PGD2-induced increase in intranasal pressure in a guinea-pig model. Similar to reports in humans, in guinea pigs nasal airway resistance was immediately increased by PGD2 application to the nose, and this was almost completely suppressed by orally administered S-5751 at 1 mg kg, suggesting that PGD2-induced nasal blockage is mediated via DP1 10 . To clarify the role of PGD2 in the onset of allergic rhinitis and the potential of a DP1 antagonist...

Drug Discovery from the

Marine ecosystems in particular have been demonstrated to be a wide source of biological and chemical biodiversity 18 (Fig. 3). Such chemical diversity will inevitably lead to new potential drug candidates 19, 20 . The reasons for this chemical diversity can be partially found in the following points 21 (i) two-thirds of the planet is covered by the sea (ii) life started in the sea 3.500 million years ago (on earth, only 600 million years ago) (iii) sea-water life conditions (pH, salinity,...

Research and Education in Molecular and Functional Imaging at Tohoku University

In 1977, the Cyclotron and Radioisotope Center (CYRIC) was founded at Tohoku University for the multipurpose use of a cyclotron, including nuclear physics, nuclear chemistry, solid-state physics, and radioisotope production for biology and medicine. Clinical studies were started at CYRIC in 1982 following the first installation of a PET scanner in 1981. In 1976, the production of 18F FDG had already been successfully done, initially for brain research at CYRIC, and the use of 18F FDG was later...

Imaging for Pathophysiological Evaluation and Early Diagnosis of Alzheimers Disease AD

In recent years, the number of patients with dementia has been increasing. The deposition of senile plaques SPs in the brain has been demonstrated to represent the neuropathological characteristics of AD 13 . The progressive accumulation of SPs has been considered to be fundamental to the initial development of AD. The deposition of SPs in the brain is present even in very mild AD and precedes the initiation of cognitive impairment at the clinical level 43, 44 . That is why noninvasive imaging...

Summary

Prostaglandin D2 PGD2 is a major lipid mediator produced by mast cells in response to IgE-dependent stimuli. In patients with allergic diseases such as allergic rhinitis and asthma, the level of PGD2 is known to increase in nasal and bronchial lavage fluids after allergen challenge. Although PGD2 has been reported to exert a variety of inflammatory effects such as increases in nasal airway resistance and vascular permeability and eosinophil infiltration, there are few reports on the efficacy of...

Development of Second Generation DPI Antagonist

Based on nonclinical and clinical studies with S-5751, we concluded that the failure to obtain clear efficacy with S-5751 was due to its inadequate DP1 antagonistic action, particularly in the presence of albumin, and insufficient plasma concentration to show a maximum effect in humans even at the highest dose used in clinical studies. To overcome the shortcomings of S-5751, a second-generation DP1 antagonist, S-555739, was successfully produced at Shionogi Research Laboratories through...