Synthesis and functionality of dendrimer with finely controlled metal assembly

AbstractIntegrated research on the synthesis and functionality of macromolecular metal complexes has suggested that dendritic structures exhibiting a geometrical density gradient also impart a potential gradient within the constituent molecules. Focusing on dendritic π-conjugated macromolecules containing azomethine (imine) as a metal assembly site, the stepwise radial complexation of metal ions in a dendritic phenylazomethine structure has been identified for the first time. Using this discovery, the first macromolecules with precision control of the number and position of metal molecules have been synthesized. A series of new physicochemical discoveries have followed from this success, related to stepwise radial complexation, one-step multi-electron transfer, and potential gradients. The usefulness of these new macromolecules as a nano-material has also been demonstrated through application to (1) polymer electroluminescent devices, (2) organic solar cells with high energy conversion efficiency, and (3) the storage and release of metals in a manner similar to ferritin protein

Oocyte-granulosa-theca cell interactions during preantral follicular development

The preantral-early antral follicle transition is the penultimate stage of follicular development in terms of gonadotropin dependence and follicle destiny (growth versus atresia). Follicular growth during this period is tightly regulated by oocyte-granulosa-theca cell interactions. Formation of the theca cell layer is a key event that occurs during this transitional stage. Granulosal factor(s) stimulates the recruitment of theca cells from cortical stromal cells, while oocyte-derived growth differentiation factor-9 (GDF-9) is involved in the differentiation of theca cells during this early stage of follicular development. The preantral to early antral transition is most susceptible to follicular atresia. GDF-9 promotes follicular survival and growth during transition from preantral stage to early antral stage by suppressing granulosa cell apoptosis and follicular atresia. GDF-9 also enhances preantral follicle growth by up-regulating theca cell androgen production. Thecal factor(s) promotes granulosa cell proliferation and suppress granulosa cell apoptosis. Understanding the intraovarian mechanisms in the regulation of follicular growth and atresia during this stage may be of clinical significance in the selection of the best quality germ cells for assisted reproduction. In addition, since certain ovarian dysfunctions, such as polycystic ovarian syndrome and gonadotropin poor-responsiveness, are consequences of dysregulated follicle growth at this transitional stage, understanding the molecular and cellular mechanisms in the control of follicular development during the preantral-early antral transition may provide important insight into the pathophysiology and rational treatment of these conditions

Characterization of the role of the tumor marker Nup88 in mitosis

Nuclear pore complexes are massive multiprotein channels responsible for traffic between the nucleus and cytoplasm, and are composed of approximately 30 proteins, termed nucleoporins (Nup). Our recent studies indicated that the nucleoporins Rae1 and Tpr play critical roles in maintaining the spindle bipolarity during cell division. In the present study, we found that another nucleoporin, Nup88, was localized on the spindles together with Nup214 during mitosis. Nup88 expression is linked to the progression of carcinogenesis, Nup88 has been proposed as a tumor marker. Overexpression of Nup88 enhanced multinucleated cell formation. RNAi-mediated knockdown of Nup88 disrupted Nup214 expression and localization and caused multipolar spindle phenotypes. Our data indicate that proper expression of Nup88 is critical for preventing aneuploidy formation and tumorigenesis

Luteinizing hormone-induced Akt phosphorylation and androgen production are modulated by MAP Kinase in bovine theca cells

<p>Abstract</p> <p>Background</p> <p>Theca cells play an important role in controlling ovarian steroidogenesis by providing aromatizable androgens for granulosa cell estrogen biosynthesis. Although it is well established that the steroidogenic activity of theca cells is mainly regulated by LH, the intracellular signal transduction mechanisms that regulate thecal proliferation and/or steroidogenesis remain obscure. In this study, we examined whether and how LH controls the PI3K/Akt signaling pathway and androgen production in bovine theca cells. We also explored whether this LH-induced PI3K/Akt activation is modulated with other signaling pathways (i.e. PKA and MAPK).</p> <p>Methods</p> <p>Ovarian theca cells were isolated from bovine small antral follicles and were incubated with LH for various durations. Phospho-Akt and total-Akt content in the cultured theca cells were examined using Western blotting. Androstenedione levels in the spent media were determined using EIA. Semi-quantitative RT-PCR analyses were conducted to analyze the mRNA levels of CYP17A1 and StAR in the theca cells. To examine whether Akt activity is involved in theca cell androgen production, the PI3K inhibitors wortmannin and LY294002 were also added to the cells.</p> <p>Results</p> <p>Akt is constitutively expressed, but is gradually phosphorylated in cultured bovine theca cells through exposure to LH. LH significantly increased androstenedione production in bovine theca cells, whereas addition of the wortmannin and LY294002 significantly decreased LH-induced androstenedione production. LH significantly increased CYP17A1 mRNA level in theca cells, whereas addition of LY294002 significantly decreased LH-induced CYP17A1 expression. Neither LH nor PI3K inhibitors alter the mRNA levels of StAR in theca cells. Although H89 (a selective inhibitor of PKA) does not affect LH-mediated changes in Akt, U0126 (a potent MEK inhibitor) suppressed LH-induced Akt phosphorylation, CYP17A1 expression, and androgen production in theca cells.</p> <p>Conclusion</p> <p>These results indicate that LH stimulates CYP17 mRNA expression and androgen production in theca cells via activation of the PI3K/Akt pathway. The LH-induced Akt phosphorylation and androgen production are modulated by the MAPK signaling in bovine theca cells.</p

非営利組織の経営改革 -社会福祉協議会の事例から-

本稿では、社会的課題の解決を担う組織の一つとして、非営利組織の経営改革に着目する。具体的には、大阪府A 市の社会福祉協議会(以下「当法人」という)を事例とし、地域福祉の推進という「社会的」ミッションを元来有する当法人が、「事業性(自立経営)」の確立を目指す改革プロセスについて、ソーシャル・マネジメントの視点から分析する。まず、企業のマネジメント手法の導入という側面を検討し、その現状と課題を整理する。次に、本稿で構築した「企業と社会」論の枠組みを援用し、「地域に開かれた社会福祉協議会の閉鎖性」ともいうべき、ステイクホルダーとの関わりの弱さを明らかにし、今後の社会福祉協議会に必要な取り組みを考える

ピクロトキシンの作用を通しての興奮収縮連関機構の解明

金沢大学医学部研究課題/領域番号:X46095-----34605, 研究期間(年度): 1971出典：研究課題「ピクロトキシンの作用を通しての興奮収縮連関機構の解明」課題番号 X46095-----34605（KAKEN：科学研究費助成事業データベース（国立情報学研究所）） （https://kaken.nii.ac.jp/ja/grant/KAKENHI-PROJECT-X46095-----34605/）を加工して作