Near-Infrared Luciferin Analogs for <em>In Vivo</em> Optical Imaging

The firefly bioluminescence reaction has been exploited for in vivo optical imaging in life sciences. To develop highly sensitive bioluminescence imaging technology, many researchers have synthesized luciferin analogs and luciferase mutants. This chapter first discusses synthetic luciferin analogs and their structure–activity relationships at the luminescence wavelength of the firefly bioluminescence reaction. We then discuss the development of luciferin analogs that produce near-infrared (NIR) light. Since NIR light is highly permeable for biological tissues, NIR luciferin analogs might sensitively detect signals from deep biological tissues such as the brain and lungs. Finally, we introduce two NIR luciferin analogs (TokeOni and seMpai) and a newly developed bioluminescence imaging system (AkaBLI). TokeOni can detect single-cell signals in mouse tissue and luminescence signals from marmoset brain, whereas seMpai can detect breast cancer micro-metastasis. Both reagents are valid for in vivo bioluminescence imaging with high sensitivity

Optogenetic Stimulation of 5-HT Neurons in the Median Raphe Nucleus Affects Anxiety and Respiration

Anxiety affects respiration, and in turn perturbs the internal environment, although the neuronal systems controlling anxiety-related respiration remain unclear. Recent reports indicate that serotonin（5-HT）neurons in the median raphe nucleus（MRN）enhance anxiety. In the present study, we aimed to clarify the contribution of 5-HT neurons in the MRN to anxiety and respiratory control using mice expressing a channelrhodopsin-2 variant-enhanced yellow fluorescent protein（ChR2 ［C128S］-EYFP; a step-function opsin）in the central 5-HT neurons. We applied an optogenetic method to bigenic mice expressing ChR2［C128S］-EYFP in 5-HT neurons and to monogenic mice without such expression. Photostimulation of free-moving mice was performed using a wireless system through an optical fiber pre-inserted above the MRN, and respiratory variables were measured using whole-body plethysmography. Anxiety was evaluated using an elevated-plus maze test. In the bigenic mice, we confirmed ChR2［C128S］-EYFP expression in tryptophan hydroxylase 2（a brain 5-HT synthase）-positive neurons in the raphe nuclei of the mesopontine, such as the MRN and the dorsal raphe nucleus. Blue light illumination to the MRN of the bigenic mice significantly increased respiratory rate and minute ventilation without affecting tidal volume, and significantly decreased the time spent in the open arms of the elevated plus maze without changing distance traveled, compared with monogenic mice. These results suggest that 5-HT neuron activity in the MRN increases anxiety-like behavior without affecting locomotor activity, enhances respiratory rhythm and minute ventilation without changing tidal volume, and can mimic anxiety-related respiratory responses in humans

Effects of calcium salts of long-chain fatty acids and rumen-protected methionine on plasma concentrations of ghrelin, glucagon-like peptide-1 (7 to 36) amide and pancreatic hormones in lactating cows

Our objective was to determine the effects of calcium salts of long-chain fatty acids (CLFAs) and rumen-protected methionine (RPM) on plasma concentrations of ghrelin, glucagon-like peptide-1 (7 to 36) amide, and pancreatic hormones in lactating cows. Four Holstein cows in midlactation were used in a 4 by 4 Latin square experiment in each 2-wk period. Cows were fed corn silage-based diets with supplements of CLFAs (1.5% added on dry matter basis), RPM (20 g/d), CLFAs plus RPM, and without supplement. Jugular blood samples were taken from 1 h before to 2 h after morning feeding at 10-min intervals on day 12 of each period. CLFAs decreased dry matter intake, but RPM did not affect dry matter intake. Both supplements of CLFAs and RPM did not affect metabolizable energy intake and milk yield and composition. Plasma concentrations of NEFAs, triglyceride (TG), and total cholesterol (T-Cho) were increased with CLFAs alone, but increases of plasma concentrations of TO and T-Cho were moderated by CLFAs plus RPM. Calcium salts of long-chain fatty acids increased plasma ghrelin concentration, and the ghrelin concentration with CLFAs plus RPM was the highest among the treatments. Plasma concentrations of glucagon-like peptide-1, glucagon, and insulin were decreased with CLFAs, whereas adding RPM moderated the decrease of plasma glucagon concentration by CLFAs. These results indicate that the addition of methionine to cows given CLFAs increases plasma concentrations of ghrelin and glucagon associated with the decrease in plasma concentrations of TO and T-Cho

領域別臨地実習に向けた模擬患者演習による看護系大学生の学習意欲への影響 : 演習実施者と観察者での教育効果の違い

本研究の目的は、模擬患者演習における演習実施者と観察者での学習意欲に対する教育効果がどのように異なるのかについて明らかにし、今後の演習における課題を検討することである。2011年9月にA大学看護学部3年生86名を対象とし模擬患者演習を実施し、その前後に質問紙調査を行った。その結果、観察者では看護師を目指す学習意欲が向上していた。演習実施者の学習意欲では、看護へのイメージ化とともに「学習」に関する項目に有意な変化があったことから、自分の学習に対する具体的な課題を見出し、演習において現場に近い感覚が得られたことが窺えた

看護系大学生の学習意欲とコミュニケーション能力に関する研究

本研究の目的は、1)模擬患者との演習を通して、看護系大学生の学習意欲およびコミュニケーション能力の変化を明らかにする、2)1)以外の模擬患者との演習を通した学生の学びを明らかにすることである。領域別実習前の3回生81名に対して、模擬患者による演習の前後に質問紙調査を実施した。演習前の看護系大学生は、看護師の仕事の内容に関連する学習意欲が低く、また相手の背景に踏みこんだコミュニケーションへの自己評価が低い実態が明らかとなった。そして、模擬患者による演習によって、学習そのものへの意欲、看護師へのあこがれが増していた。その反面コミュニケーション能力に対して自己評価が下がっていたが、これは自らを客観視していると考えられた。この演習によって、「生きた患者」への看護を体験することができ、領域別実習に向けて有効な準備段階となった

How to Select Firefly Luciferin Analogues for In Vivo Imaging

Bioluminescence reactions are widely applied in optical in vivo imaging in the life science and medical fields. Such reactions produce light upon the oxidation of a luciferin (substrate) catalyzed by a luciferase (enzyme), and this bioluminescence enables the quantification of tumor cells and gene expression in animal models. Many researchers have developed single-color or multicolor bioluminescence systems based on artificial luciferin analogues and/or luciferase mutants, for application in vivo bioluminescence imaging (BLI). In the current review, we focus on the characteristics of firefly BLI technology and discuss the development of luciferin analogues for high-resolution in vivo BLI. In addition, we discuss the novel luciferin analogues TokeOni and seMpai, which show potential as high-sensitivity in vivo BLI reagents