115 research outputs found
FSH modulates PKAI and GPR3 activities in mouse oocyte of COC in a gap junctional communication (GJC)-dependent manner to initiate meiotic resumption.
No full textMany studies have shown that cyclic adenosine-5'-monophosphate (cAMP)-dependent protein kinase A (PKA) and G-protein-coupled receptor 3 (GPR3) are crucial for controlling meiotic arrest in oocytes. However, it is unclear how gonadotropins modulate these factors to regulate oocyte maturation, especially by gap junctional communication (GJC). Using an in vitro meiosis-arrested mouse cumulus-oocyte complex (COC) culture model, we showed that there is a close relationship between follicle-stimulating hormone (FSH) and the PKA type I (PKAI) and GPR3. The effect of FSH on oocyte maturation was biphasic, initially inhibitory and then stimulatory. During FSH-induced maturation, rapid cAMP surges were observed in both cumulus cells and oocyte. Most GJC between cumulus cells and oocyte ceased immediately after FSH stimulation and recommenced after the cAMP surge. FSH-induced maturation was blocked by PKAI activator 8-AHA-cAMP. Levels of PKAI regulatory subunits and GPR3 decreased and increased, respectively, after FSH stimulation. In the presence of the GJC inhibitor carbenoxolone (CBX), FSH failed to induce the meiotic resumption and the changes in PKAI, GPR3 and cAMP surge in oocyte were no longer detected. Furthermore, GPR3 was upregulated by high cAMP levels, but not by PKAI activation. When applied after FSH stimulation, the specific phosphodiesterase 3A (PDE3A) inhibitor cilostamide immediately blocked meiotic induction, regardless of when it was administered. PKAI activation inhibited mitogen-activated protein kinase (MAPK) phosphorylation in the oocytes of COCs, which participated in the initiation of FSH-induced meiotic maturation in vitro. Just before FSH-induced meiotic maturation, cAMP, PKAI, and GPR3 returned to basal levels, and PDE3A activity and MAPK phosphorylation increased markedly. These experiments show that FSH induces a transient increase in cAMP levels and regulates GJC to control PKAI and GPR3 activities, thereby creating an inhibitory phase. After PDE3A and MAPK activities increase, meiosis resumes
Research on Financing Cost of SMB in P2P Lending Platform
No full textabstract: How to play the advantages of network loan platform to reduce the financing costs of net loan platform both in theory and practice has important significance. In this paper, we use the method of qualitative and quantitative combination. First of all, through the interview of the net loan platform practitioners, the financing cost of the net loan platform comes from the internal and external parts. Part of the network loan platform should be righteous, but counterproductive human and material costs, credit costs, information efficiency, transaction costs and matching costs; part of the emerging industry as a challenge, compliance costs, technical costs and safety costs and other cost. And put forward the top design credit system, promote the credit system; build a unified development of regulatory policies to reduce compliance risks; increase investment in technology, share the improvement of technological progress bonuses. Through the establishment of the regression model, the paper analyzes the influence of various indexes of network loan platform on the cost of network reception. It is found that the background of net loan platform with shareholder and executive team as the proxy variable has significant influence on the cost of network loan platform. The effect is not significant. Risk control indicators on the net loan platform cost has a significant negative effect. The impact of operating capacity on the cost of net loan platform differentiation, the acquisition of the cost of positive relations, the other is negative relations. Policy compliance indicators of financial security on the net loan platform cost significantly, the other did not significantly affect the role of liquidity indicators of differentiation, the average borrowing period will significantly affect the net loan platform costs, liquidity is a negative impact. And finally put forward the policy and recommendations and research limitations and future direction.Dissertation/ThesisDoctoral Dissertation Business Administration 201
Study on Solid Fermentation and Antioxidant Function of Natto
No full text[Objectives] To study the optimum conditions of solid fermentation of natto with antioxidant function as an index. [Methods] Single factor experiment and orthogonal experiment were designed to study the effects of temperature, time, initial pH and inoculum amount on the antioxidant activity of natto solid fermentation. The optimum conditions of natto solid fermentation were determined and the antioxidant activity of natto extract was compared. [Results] The optimal fermentation conditions were as follows: temperature 32 ℃, initial pH 7.0, inoculation amount 8%, fermentation time 32 h. The hydroxyl radical scavenging rate of natto solid fermentation crude extract was the highest, which was 82.7%. The optimized natto fermentation extract showed stronger scavenging ability for ·OH and and showed obvious dose-effect relationship. IC50 was 3.63 and 4.24 mg/mL, respectively, and the scavenging efficiency was 1.3 and 1.9 times higher than that of the unoptimized fermentation extract, respectively. [Conclusions] Natto is rich in nattokinase and other functional factors, and its antioxidant activity can be improved by optimizing fermentation technology, so that natto products can be widely used, including cosmetic raw materials, natto skin care soap, health food and medicine, etc., and have a broader development prospect
The Analysis of China\u27s Marketing Consultant Work from the Perspective of Knowledge
No full textWith the continuous development and improvement of China\u27s market economic system, the traditional common marketing mode has been impacted and deconstructed. In the process of resisting the extrusion of competitive companies and adapting to the selection of consumer audiences, enterprises have gradually built a new consulting marketing mode. Based on the author\u27s past real work experience and later field research, this paper expounds the differences between the consultant analysis and the traditional sales in the modern Chinese market from four aspects: market dimensionality, information service value, communication subjectivity and work composition, and it comes to a series of conclusions that, compared with traditional sales, the consultant demand analyst mainly faces the oriented market and semi non oriented market, can provide customers with professional information services that form a knowledge system, gives the customer a sense of subjectivity in the communication on the surface but actually holds the dominant power in the dialogue, and its work content is mainly to maintain the stickiness between users and enterprise products; Then, it discusses the practical path for consultants to better carry out business from two aspects of personal skills and platform activities, and points out that consultants can increase the transaction rate of products by amplifying the customer\u27s demand points, strengthening the customer\u27s anxiety, and taking advantage of the limited time and discount during the platform activity period; Finally, it reveals the essence of the work of consultants and demand analysts and the development trend of the allocation and reconstruction of the functions of modern posts
Effect of PKAI on the FSH-induced resumption of meiosis in COC.
No full text<p>(A) The PKAI activator 8-AHA-cAMP (8-AHA) dose-dependently inhibited the FSH-induced resumption of meiosis in COC. (B) Cumulus expansion. Cumulus expansion was detected at the end of 22 h culture. HX, control; FSH, 50 IU/L FSH; 50 µM 8-AHA-cAMP; 100 µM 8-AHA-cAMP. <i>Scale bar</i>, approximately 50 µm. (C) The crucial period for the effect of PKAI on FSH stimulation. When 8-AHA-cAMP was added to cultures 3 or 4 h after the start of culture, meiotic induction was significantly reduced. Administration of 8-AHA-cAMP 5 h after the start of culture did not inhibit the induction of meiosis. Columns with different superscripts are significantly different (<i>P</i><0.05).</p
Correlations between FSH and PDE3A.
No full text<p>(A) Inhibiting PDE3A blocked the effect of FSH on maturation. COCs were cultured in HX medium containing 50 IU/L FSH. Cilostamide (cilo) was added to one set of cultures 3, 4, 5, 6, 7, or 8 h after the start of culture. GVBD was assessed at 22 h (gray bars). The other set of cultures was examined at different intervals up to 8 h (black bars). Cilostamide blocked further meiotic maturation at each time point at which it was administered. GVBD percentage of the controls is indicated by the box. (B) Inhibiting PDE3A didn't affect cumulus expansion induced by FSH. Cumulus expansion was detected at the end of 22 h culture. HX, control; FSH, 50 IU/L FSH; FSH 3 h+Cilo, Cilostamide (cilo) was added to culture 3 h after the start of FSH treatment. FSH 8 h+Cilo, Cilostamide (cilo) was added to culture 8 h after the start of FSH treatment. <i>Scale bar</i>, approximately 50 µm. (C) After stimulation with FSH for 6 h, oocyte PDE3A activity significantly increased. Means marked with asterisks are significantly different (*<i>P</i><0.05, **<i>P</i><0.01).</p
Effects of FSH on PKAI, and decrease in PKAI regulatory subunit (RIα) levels after activation of PKAI.
No full text<p>(A) FSH reduced PKAI regulatory subunit RIα levels, but not levels of the catalytic subunit (C) of PKAI, in oocytes of COCs (DOs), but not cumulus cells (CCs), 2 h after the start of culture. DOs and CCs from 200 COCs treated/not treated with FSH were collected at various time points and analyzed by Western blotting. (B) PKAI activation resulted in a decrease in RIα levels in oocytes. COCs were incubated in HX medium supplemented with increasing concentrations of 8-AHA-cAMP (0–250 µM) for 2 h. Oocytes of COCs were collected at 2 h for Western blotting analysis of PKAI RIα and C levels. 8-AHA-cAMP reduced oocyte RI levels in a dose-dependent fashion, but had no obvious effect on PKAI C levels. Western blotting experiments were performed at least three times with similar results. The blot shown is representative of three experiments.</p
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