Shape transformations of lipid vesicles by insertion of bulky-head lipids

Lipid vesicles, in particular Giant Unilamellar Vesicles (GUVs), have been increasingly important as compartments of artificial cells to reconstruct living cell-like systems in a bottom-up fashion. Here, we report shape transformations of lipid vesicles induced by polyethylene glycol-lipid conjugate (PEG lipids). Statistical analysis of deformed vesicle shapes revealed that shapes vesicles tend to deform into depended on the concentration of the PEG lipids. When compared with theoretically simulated vesicle shapes, those shapes were found to be more energetically favorable, with lower membrane bending energies than other shapes. This result suggests that the vesicle shape transformations can be controlled by externally added membrane molecules, which can serve as a potential method to control the replications of artificial cells

Psychological Variables Underlying Cooperative Behavior for Local Communities: The Case of Regional Charismas in Japan

Many empirical findings have shown that local communities can be improved if at least one altruistic person engages in cooperative behavior for the benefit of the community as in the case of The 100 charisma ambassadors of tourism in Japan This paper conducted a multilevel analysis to elucidate the psychological variables underlying such cooperative behavior CB A questionnaire survey was conducted using items previously proposed for measuring determinant factors of CB The respondents were the 100 charisma ambassadors of tourism n 95 residents living in the same region as the charismas n 400 and residents living in other regions n 500 By comparing different groups personality and environmental factors promoting CB were examined The results indicate that Schwartz s norm-activation factors contribute to the personality characteristics of the charismas and that feelings of sympathy among residents contribute to the environmental characteristics of the locality of the charisma

ラット ソクザカク ノ IPSP ニ タイスル アデノシン ト カンナビノイド ニヨル ダツブンキョク ユウドウ ヨクセイ ノ ユウドウ

A short period of depolarization evokes transient suppression of neurotransmitter release (Depolarization-induced Suppression of IPSP: DSI). Recent studies suggest that cannabinoids are candidates for the retrograde messenger required to induce DSI in the hippocampal CA1 area. A G protein-coupled process and inhibition of N-type calcium channels at the presynaptic terminals are believed to be involved in the induction mechanism. We examined DSI induction in the nucleus accumbens in which inputs from multiple sites in the telencephalon, including the hippocampus and basolateral amygdala, converge. Using whole-cell recording from a horizontal slice preparation of nucleus accumbens from the rat brain, we monitored the effect of endogenous cannabinoids on DSI induction and found that 300 nM AM281, a selective cannabinoid CB1 receptor antagonist, resulted in blockade of DSI. Adenosine is reported to suppress neurotransmitter release by inhibiting N-type calcium channels, which is a similar mechanism to that reported for cannabinoid-induced DSI. We therefore examined the effect of endogenous adenosine on DSI induction using DPCPX, a selective A1 receptor antagonist, and found that DSI induction was blocked in the presence of 100 nM DPCPX. These results suggest that cooperative activation of CB1 and A1 receptors contributes to DSI induction in the rat nucleus accumbens.　Key words: Nucleus accumbens, DSI, Cannabinoid, Adenosine, Whole-cell recording短時間の脱分極は一過性に伝達物質の放出を抑制する（脱分極誘導 IPSP 抑制：DSI）。最近の研究によればカンナビノイドは海馬 CA1 領域における DSI 誘導に関わる逆行性伝達物質であることが示されている。誘導のメカニズムとしてはＧ蛋白に結合した過程やＮ型のカルシウムチャンネルが関与していると考えられている。我々は、海馬・基底外側扁桃体などを含んだ終脳における多くの部位からの入力を統合している場所である側座核において、DSI の誘導を検討した。側座核の水平断薄切標本を用いて whole cell recording を行い、DSI誘導に関する内因性カンナビノイドの影響を調べたところ、選択的 CB1 カンナビノイド受容体阻害薬である 300nM の AM281 が DSI の誘導を阻害した。アデノシンはＮ型カルシウムチャンネルを阻害することによって伝達物質の放出を抑制することが報告されているが、この効果はカンナビノイドの効果と類似している。それ故我々は選択的な A1 アデノシン受容体の阻害薬である DPCPX を用いて、DSI 誘導に関する内因性アデノシンの効果を調べてみた。その結果、100nM の DPCPX が DSI の誘導を阻害することがわかった。これらの結果から CB1 と A1 受容体活性が側座核における DSI の誘導に関わっていることが示された。　キーワード：側座核、DSI 、カンナビノイド、アデノシン、whole-cell recordin

Scavenger Receptor B2 as a Receptor for Hand, Foot, and Mouth Disease and Severe Neurological Diseases

Enterovirus 71 (EV71) is one of the major causative agents of hand, foot, and mouth disease (HFMD). Infection with EV71 is occasionally associated with severe neurological diseases such as acute encephalitis, acute flaccid paralysis, and cardiopulmonary failure. Because cellular receptors for viruses play an important role in cell, tissue, and species tropism, it is important to identify and characterize the receptor molecule. Recently, cellular receptors and host factors that stimulate EV71 infection have been identified. Several lines of evidence suggest that scavenger receptor class B, member 2 (SCARB2) plays critical roles in efficient EV71 infection and the development of disease in humans. In this review, we will summarize the findings of recent studies on EV71 infection and on the roles of SCARB2