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In this study, an ecofriendly analytical method was developed for determining glutathione (GSH) levels in biomatrix samples. 9-(bromomethyl)acridine was used for the first time as a derivatization reagent in GSH analysis. Microwave-assisted derivatization reduced the reaction time to 1 min. After derivatization, coacervative extraction was employed to extract GSH derivative from the complex biomatrix and to increase sensitivity. Because the negatively charged group of the GSH derivative was neutralized by the extracting agent Aliquat 336, aggregates formed without any coacervating agents. Furthermore, capillary liquid chromatography coupled with ultraviolet detection was applied to decrease waste generation and increase selectivity. This method successfully quantified GSH levels in various biomatrices, including erythrocytes, HaCaT cells, BALB/3T3 cells, and 3T3-L1 fibroblasts. This method only required a low sample volume (≤10 μL). A standard addition method was utilized to spike the biomatrix samples with 0–4.8 nmol GSH to construct calibration curves. The proposed method performed well, with a determination coefficient of 0.999 and relative standard deviations of less than 6.59% for the slope and the intercept, as determined by linear regression analysis. The limit of detection of GSH in the standard solution was 800 nM or 0.4 pmol. Compared to non-derivatized GSH, the proposed method for detecting derivatized GSH provides 750-fold greater sensitivity.

Excess free fatty acid accumulation from abnormal lipid metabolism results in the insulin resistance in peripheral cells, subsequently causing hyperinsulinemia, hyperglycemia and/or hyperlipidemia in diabetes mellitus (DM) patients. Herein, we investigated the effect of phenolic acids on glucose uptake in an insulin-resistant cell-culture model and on hepatic insulin resistance and inflammation in rats fed a high-fat diet (HFD). The results show that vanillic acid (VA) demonstrated the highest glucose uptake ability among all tested phenolic acids in insulin-resistant FL83B mouse hepatocytes. Furthermore, rats fed HFD for 16 weeks were orally administered with VA daily (30 mg/kg body weight) at weeks 13–16. The results show that levels of serum insulin, glucose, triglyceride, and free fatty acid were significantly decreased in VA-treated HFD rats (p &lt, 0.05), indicating the protective effects of VA against hyperinsulinemia, hyperglycemia and hyperlipidemia in HFD rats. Moreover, VA significantly reduced values of area under the curve for glucose (AUCglucose) in oral glucose tolerance test and homeostasis model assessment-insulin resistance (HOMA-IR) index, suggesting the improving effect on glucose tolerance and insulin resistance in HFD rats. The Western blot analysis revealed that VA significantly up-regulated expression of hepatic insulin-signaling and lipid metabolism-related protein, including insulin receptor, phosphatidylinositol-3 kinase, glucose transporter 2, and phosphorylated acetyl CoA carboxylase in HFD rats. VA also significantly down-regulated hepatic inflammation-related proteins, including cyclooxygenase-2 and monocyte chemoattractant protein-1 expressions in HFD rats. These results indicate that VA might ameliorate insulin resistance via improving hepatic insulin signaling and alleviating inflammation pathways in HFD rats. These findings also suggest the potential of VA in preventing the progression of DM.

This study investigated the effect of phenolic acid on memory decline and cerebral carbohydrate metabolism in rats fed a high-fat diet (HFD), which induced hyperinsulinemia. First, among eleven tested phenolic acids, caffeic acid (CA) was demonstrated to induce the highest glucose uptake capacity in insulin-resistant Neuro 2a mouse neuroblastoma cells. Next, male rats fed a HFD were treated with daily oral CA (30 mg/kg body weight) for 30 weeks. Cognitive performance trials were conducted to investigate the effect of CA on ameliorating memory impairment. Cerebral tissues were analyzed to determine whether CA affected brain carbohydrate metabolism and/or alleviated insulin and leptin resistance. Our results suggested that CA significantly reduced plasma glucose and insulin levels, and it alleviated insulin resistance (HOMA-IR) in HFD-induced hyperinsulinemic rats. Concurrently, passive avoidance tests revealed that orally administered CA significantly improved memory impairments in HFD rats. Western blot analysis demonstrated that CA significantly increased the expression of insulin signaling-related proteins, including the insulin receptor, phosphatidylinositol-3-kinase, Akt/protein kinase B, and insulin degrading enzyme. CA also increased the expression of leptin signaling-related proteins, including leptin receptor and pJAK2Tyr813/JAK2 in the cortex of HFD rats. These findings demonstrated that CA showed promise as a drug or food supplement for preventing the progression of dementia.

This paper discusses the reaction of a manager to voluntary disclosure and the strategic decisions within social contexts concerning financial disclosure . Extensions of the base model examine the interaction of financial disclosure , investor relations, and managerial incentive to disclose, such as demonstrating a signaling game between a manager and investors for financial disclosure . This paper demonstrates how Rule 10b-5 of the 1934 Securities and Exchange Act fails to induce voluntary disclosure. While there is a link between the way in which companies raise external capital and the information that the companies disclose, the transformed reaction of disclosure is the signal for the company’s financing policy. With the reaction of investors to voluntary disclosure after information is disclosed, this paper analyzes why the disclosure of information has regulated results as noise for investment. The extra requirement for information shifts the positions of investors toward managers concerning the policy of financial disclosure .

This paper discusses and explores three situations under asymmetric information. First, companies with a higher level of corporate governance provisions compensate the owner–manager with a higher managerial reward for information disclosed. Second, there are significant and positive relationships between information disclosed and corporate governance provisions, as well as between company value and corporate governance provisions. The higher proportion of a firm held by the largest owner(s) has negative impacts on information disclosed and shareholder rights as outside investors underestimate the companies' performance caused by insufficient effort of the owner–manager or by other factors. Third, audits improve moral hazard when outside investors are informed of bad company performance by underestimating the stock price.

Parabens are common preservatives and environmental hormones. As such, possible detrimental health effects could be amplified through their widespread use in foods, cosmetics, and pharmaceutical products. Thus, the determination of parabens in such products is of particular importance. This study explored vortex-assisted dispersive liquid-liquid microextraction techniques based on the solidification of a floating organic drop (VA-DLLME-SFO) and salt-assisted cloud point extraction (SA-CPE) for paraben extraction. Microanalysis was performed using a capillary liquid chromatography-ultraviolet detection system. These techniques were modified successfully to determine four parabens in 19 commercial products. The regression equations of these parabens exhibited good linearity (r2=0.998, 0.1-10μg/mL), good precision (RSD

This article demonstrates how Rule 10b-5 of the 1934 Securities and Exchange Act fails to induce voluntary disclosure. We show that company owners may deter the disclosure policy for their financing decisions. While there is a link between the way in which firms raise external capital and the information which their firms disclose, we show that the transformed reaction of disclosure is the signal for the company's financing policy.

This paper examines the determinants of very low birth weight infant (or neonatal) mortality using the Taiwan National Health Insurance Research database from 1997 to 2009. After infants are discharged from hospital, it is not possible to track their mortality, so the Cox proportional hazard model is used to analyze the very low birth weight infant mortality rate. In order to clarify treatment responsibility and to avoid selective referral effects, we use the number of infants treated in the preceding five years to observe the effect of a physician’s and hospital’s medical experience on the mortality rate of hospitalized minimal birth weight infants. The empirical results show that, given disease control variables, a higher infant weight, higher quality hospitals, increased hospital medical experience, and higher investment in pediatrics can reduce the mortality rate significantly. However, an increased physician’s medical experience does not seem to influence significantly the very low birth weight infant mortality rate.

Activated microglia exerts both beneficial and deleterious effects on neurons, but the signaling mechanism controlling these distinct responses remain unclear. We demonstrated that treatment of microglial cultures with the PAR-2 agonist, 2-Furoyl-LIGRLO-NH2, evoked early transient release of BDNF, while sustained PAR-2 stimulation evoked the delayed release of inflammatory cytokines (IL-1β and TNF-α) and nitric oxide. Culture medium harvested during the early phase (at 1 h) of microglial activation induced by 2-Furoyl-LIGRLO-NH2 (microglial conditioned medium, MCM) had no deleterious effects on cultured neurons, while MCM harvested during the late phase (at 72 h) promoted DNA fragmentation and apoptosis as indicated by TUNEL and annexin/PI staining. Blockade of PAR-1 during the early phase of PAR-2 stimulation enhanced BDNF release (by 11%, small but significant) while a PAR-1 agonist added during the late phase (24 h after 2-Furoyl-LIGRLO-NH2 addition) suppressed the release of cytokines and NO. The neuroprotective and neurotoxic effects of activated microglial exhibit distinct temporal profiles that are regulated by PAR-1 and PAR-2 stimulation. It may be possible to facilitate neuronal recovery and repair by appropriately timed stimulation and inhibition of microglial PAR-1 and PAR-2 receptors.

A broadband microstrip bandpass filter (BPF) with compact size, sharp skirt and wide upper-stopband performance is proposed using the triple-mode stub-loaded resonator. The resonator can generate one odd mode and two even modes in the desired passband. Due to the main path signal counteraction, two transmission zeros T z1 , T z2 can be created near the passband edge to achieve sharp skirt. Two transmission zeros T z4 , T z5 are created between two harmonic frequencies h m2 , h m3 by the folded open stub and the interdigital coupling feeding lines, respectively. Owing to the source-load coupling, one zero T z3 is introduced to deepen the stopband. Meanwhile, the zero T z1 is shifted to the lower cut-off frequency and the other three ones T z2 , T z4 , T z5 can be slightly turned to suppress three harmonic frequencies h m1 , h m2 , h m3 . O ne filter prototype with the fractional bandwidth 34% is designed , fabricated and measured .

Calculating of June 5, 2010 occurred in the east longitude 112.7 °, latitude 38.2 ° TaiYuan’s YangQu, ShanXi Province of the tidal force of celestial bodies Ms4.6 earthquake cycle process, and according to the cycle of integrated multi-source to analysis of temperature data to get the process of extracting earthquake images of the abnormal temperature. The result indicates that the tidal force of celestial bodies has a triggering effect on the activity of the tectonic. The temperature abnormal increase can clearly reflect the procession of the seismic fault activity: initial temperature rise →Abnormally warming →return to baseline. Microseism of this study show that the temperature anomalies in the micro-earthquakes are also a clear reflection of the process of gravitational effect microseism obviously. It is not only the abnormal warming, it is an earthquake-strong evidence of thermal anomalies, also for the use of remotesensing of earthquake prediction methods.