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The neuropeptide secretoneurin (SN) plays protective roles in myocardial ischemia. In the present study, the effect of SN in cardiac hypertrophy was investigated. We observed that, in isoproterenol (ISO) treatment induced cardiac or cardiomyocytes hypertrophy, a marked increase in the expression of endogenous SN in mouse plasma, myocardium and primary-cultured cardiomyocytes occurs. In hypertrophic mice, the heart size, heart weight/body weight (HW/BW) ratio, cardiomyocyte size, and atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) expression were significantly higher than those in controls but were effectively suppressed by SN gene therapy. Similarly, the protective effects of SN were also observed in cultured cardiomyocytes following ISO treatment. SN significantly increased the activity of catalase and superoxide dismutase (SOD) in parallel with the decrease in reactive oxygen species levels in cardiomyocytes. We observed that SN evoked the activation of all of the AMPK, P38/MAPK and ERK/MAPK pathways in cardiomyocytes, but pretreatment with only AMPK inhibitor (compound C) and ERK1/2/MAPK inhibitor (PD98059) counteracted the protective effects of SN against cardiomyocyte hypertrophy and the suppressive effects of SN on oxidant stress in cardiomyocytes. These results indicated that endogenous SN is induced in hypertrophic cardiomyocytes, and may play a protective role in the pathogenesis of cardiac hypertrophy. These results suggest that exogenous SN supplementation protects the cardiac hypertrophy induced by ISO treatment through the activation of AMPK and ERK/MAPK pathways, thus upregulating antioxidants and suppressing oxidative stress. [ABSTRACT FROM AUTHOR]

Abstract: Doxorubicin (DOX) is a wide spectrum antitumor drug, but its clinical application is limited by the cardiotoxicity. Ghrelin, a multi-functional peptide hormone with metabolic regulation in energy homeostasis, plays important roles in cardiovascular protection. Now, the underlying mechanisms of ghrelin against DOX-induced cardiomyocyte apoptosis and atrophy are still not clear. In the present study, we revealed an autophagy-dependent mechanism involved in ghrelin's protection against DOX-induced cardiomyocyte death and size decrease. We observed that DOX insult induced remarkable mortality and cardiac dysfunction in mice, and increase in LDH leakage, cardiomyocyte apoptosis and decrease in cell viability and size in mouse hearts and H9c2 cell cultures, which were effectively improved by ghrelin supplement. We further observed that the strong autophagy stirred by DOX exposure was paralleling with the serious apoptosis and size decrease in cardiomyocytes. Ghrelin, like an autophagy inhibitor, 3-MA, inhibited the DOX-induced autophagy and attenuated cardiomyocyte apoptosis and size decrease. Furthermore, ghrelin significantly reduced the intercellular oxidative stress level, a strong autophagy trigger, partly by augmenting the expression and activities of the endogenous anti-oxidative enzymes. After the further investigation in the post signaling pathways of ghrelin receptors in H9c2 cells, including ERK, p38/MAPK, JNK, AMPK and Akt, we observed that ghrelin supplement only reduced the DOX-activated AMPK and augmented the DOX-down regulated p38-MAPK and mTOR phosphorylation. Our results indicated that ghrelin effectively improved the cardiomyocyte survival and size maintenance by suppressing the excessive autophagy through both ROS inhibition and mTOR induction through suppressing AMPK activity and stimulating p38-MAPK activity. [Copyright &y& Elsevier]

With the power to find the best fit to arbitrarily complicated symmetry, machine-learning (ML)-enhanced quantum state tomography (QST) has demonstrated its advantages in extracting complete information about the quantum states. Instead of using the reconstruction model in training a truncated density matrix, we develop a high-performance, lightweight, and easy-to-install supervised characteristic model by generating the target parameters directly. Such a characteristic model-based ML-QST can avoid the problem of dealing with a large Hilbert space, but cab keep feature extractions with high precision, capturing the underlying symmetry in data. With the experimentally measured data generated from the balanced homodyne detectors, we compare the degradation information about quantum noise squeezed states predicted by the reconstruction and characteristic models; both are in agreement with the empirically fitting curves obtained from the covariance method. Such a ML-QST with direct parameter estimations illustrates a crucial diagnostic toolbox for applications with squeezed states, from quantum information process, quantum metrology, advanced gravitational wave detectors, to macroscopic quantum state generation. [ABSTRACT FROM AUTHOR]

[Display omitted] • The gas diffusion in the mesoporous channels of the MMMs followed the Knudsen mechanism. • The good affinity between the IL and CO 2 improved the CO 2 adsorption selectivity of MMMs. • IL immobilization caused the transformation from Knudsen diffusion in channels to CO 2 -facilitated diffusion. • The gas solubility coefficients of the MMMs were positively proportional to their maximum gas adsorption. • The gas diffusion coefficients in the MMMs were determined by the confined mass transfer channels. Incorporation of porous materials in a polymeric membrane is an effective strategy for improving the gas permeability of the resulting mixed matrix membranes (MMMs). However, effective improvement of selectivity of membrane toward CO 2 separation is still a significant challenge due to the insufficient CO 2 capture performance of porous materials. In this study, polyimide (PI)-based MMMs with enhanced CO 2 capture performance were prepared for CO 2 separation. First, an ionic liquid (IL) with a high affinity for CO 2 was immobilized in the inner pore structures of two types of mesoporous silica (SiO 2) molecules to form IL@SiO 2 composites. These composites were used as nanofillers to construct the MMMs. The stable immobilization of IL inside the pores of the mesoporous SiO 2 indicated that the IL@SiO 2 and MMMs both exhibited higher adsorption selectivity for CO 2. The gas solubility coefficient of the MMMs was positively proportional to their maximum gas adsorption capacity, which was determined by the gas adsorption capacity of the PI polymer and nanofillers. More interestingly, the diffusion coefficients of different gases in the MMMs were closely related to the confined mass transfer channels introduced by the nanofillers. The diffusion of CO 2 in the confined mass transfer channels of MMMs was facilitated and N 2 diffusion was slightly inhibited, which increased the diffusion selectivity of the resulting MMMs for CO 2. Combined with Maxwell–Wagner–Sillar model calculations for gas permeation, it was confirmed that IL immobilization transformed the diffusion mode of CO 2 in the confined mass transfer channels of the MMMs from Knudsen diffusion to facilitated diffusion. However, the immobilization of excessive ILs in the mesopores blocked the mass transfer channels of the MMMs, resulting in lower gas permeability and decreased CO 2 separation selectivity. [ABSTRACT FROM AUTHOR]

Targeted identification of potentially bioactive molecules from herbal medicines is often stymied by the insufficient chromatographic separation, ubiquitous matrix interference, and pervasive isomerism. An enhanced targeted identification strategy is presented and validated by the selective identification of flavonoid O -glycosides (FOGs) from Carthamus tinctorius . It consists of four steps: (i) enhanced separation and detection by offline two-dimensional liquid chromatography/LTQ-Orbitrap MS (offline 2D-LC/LTQ-Orbitrap MS) using collision-induced dissociation (CID) and high-energy C -trap dissociation (HCD); (ii) improved identification of the major aglycones by acid hydrolysis and LC-SPE-NMR; (iii) simplified spectral elucidation by high-resolution diagnostic product ions/neutral loss filtering; and (iv) more convincing structural identification by matching an in-house library. An offline 2D-LC system configuring an Acchrom XAmide column and a BEH Shield RP-18 UPLC ® column enabled much better separation of the easily co-eluting components. Combined use of CID and HCD could produce complementary fragmentation information. The intensity ratios of the aglycone ion species ([Y 0 -H] − /Y 0 − and [Y 0 -2H] − /Y 0 − ) in the HCD-MS 2 spectra were found diagnostic for discriminating the aglycone subtypes and characterizing the glycosylation patterns. Five aglycone structures (kaempferol, 6-hydroxykaempferol, 6-methoxykaempferol, carthamidin, and isocarthamidin) were identified based on the 1 H-NMR data recorded by LC-SPE-NMR. Of the 107 characterized flavonoids, 80 FOGs were first reported from C. tinctorius . Unknown aglycones, pentose, and novel acyl substituents were discovered. A new compound thereof was isolated and fully identified, which could partially validate the MS-oriented identification. This integral strategy can improve the potency, efficiency, and accuracy in the detection of new compounds from medicinal herbs and other natural sources. [ABSTRACT FROM AUTHOR]

Melatonin ( N -acetyl-5-methoxytryptamine) is documented as a hormone involved in the circadian regulation of physiological and neuroendocrine function in mammals. Herein, the effects of melatonin on the functions of porcine granulosa cells in vitro were investigated. Porcine granulosa cells were cultivated with variable concentrations of melatonin (0, 0.001, 0.01, 0.1, 1.0, and 10 ng/mL) for 48 h. Melatonin receptor agonist (IIK7) and antagonist (Luzindole, 4P-PDOT) were used to further examine the action of melatonin. The results showed optimum cell viability and colony-forming efficiency of porcine granulosa cells at 0.01 ng/mL melatonin for 48-h incubation period. The percentage of apoptotic granulosa cells was significantly reduced by 0.01 and 0.1 ng/mL melatonin within the 48-h incubation period as compared with the rest of the treatments. Estradiol biosynthesis was significantly stimulated by melatonin supplementation and suppressed for the progesterone secretion; the minimum ratio of progesterone to estradiol was 1.82 in 0.01 ng/mL melatonin treatment after 48 h of cultivation. Moreover, the expression of BCL-2, CYP17A1 , CYP19A1 , SOD1 , and GPX4 were up-regulated by 0.01 ng/mL melatonin or combined with IIK7, but decreased for the mRNA levels of BAX , P53 , and CASPASE-3 , as compared with control or groups treated with Luzindole or 4P-PDOT in the presence of melatonin. In conclusion, the study demonstrated that melatonin mediated proliferation, apoptosis, and steroidogenesis in porcine granulosa cells predominantly through the activation of melatonin receptor MT2 in vitro , which provided evidence of the beneficial role of melatonin as well as its functional mechanism in porcine granulosa cells in vitro . [ABSTRACT FROM AUTHOR]

To improve the flux, anti-fouling and dye separation performance of PES-based membranes, PES mixed-matrix membranes (MMMs) blended with ZIF-8@Ti 3 C 2 T x composites were fabricated via a facile one-pot microemulsion strategy. The introduction of hydrophilic components in the microemulsion into the PES matrix enhanced the pore structures and surface polarity of the resulting MMMs, causing them to exhibit high permeation and anti-fouling performance compared to both neat PES and MMMs with ZIF-8. The optimal membrane flux and anti-fouling performance were found to be 280 L·m−2·h−1 and 91 % (bovine serum albumin rejection), respectively, at 3 % microemulsion content. The well-distributed ZIF-8@Ti 3 C 2 T x composites in the MMMs interact with dye molecules, which strengthens the dye retention from high-salinity wastewater. Further, the pore size of the MMMs was positively correlated with the flux but negatively correlated with dye retention. In particular, the M-3 membrane exhibited high flux (140 L·m−2·h−1) and up to 98 % dye rejection in high-salinity wastewater, but its rejection of salt ions was <5 %. In addition, the dye rejection recovery rate of M-3 after each washing exceeded 93 % over 5 fouling/backwashing cycles. These results strongly suggest that MMMs incorporated with ZIF-8@Ti 3 C 2 T x composites have promising application prospects for removing trace dye pollutants from high-salinity wastewater. • ZIF-8@Ti 3 C 2 T x composites were prepared by reverse microemulsion as a nanoreactor. • Ti 3 C 2 T x could improve the dispersion of ZIF-8 in PES MMMs. • Blending with ZIF-8@Ti 3 C 2 T x enhanced the antifouling property of PES MMMs. • PES MMMs incorporating ZIF-8@Ti 3 C 2 T x have high flux in high salinity wastewater. • ZIF-8@Ti 3 C 2 T x /PES MMMs could effectively remove dye from high salinity wastewater. [ABSTRACT FROM AUTHOR]

Abstract: Ghrelin is a multifunctional peptide that actively protects against cardiovascular ischemic diseases, but the underlying mechanisms are unclear. We used CoCl2 to mimic hypoxic conditions in cardiac H9c2 cells in order to study the mechanism by which ghrelin protects cardiac myocytes against hypoxic injury by regulating the content of intracellular ROS and autophagy levels. Cell apoptosis and necrosis were evaluated by the flow cytometry assay, Hoechst staining, and LDH activity. Cell viability was detected by the WST-1 assay; ROS levels were assessed using DCFH2-DA; and Nox1, catalase and Mn-SOD were assayed by real-time PCR and activity assays. LC3II was measured by Western blot analysis. We observed that CoCl2 induced apoptosis and death of H9c2 cells in a dose- and time-dependent manner. This was characterized by an increase in cell apoptosis, LDH activity, ROS content, Nox1 expression, and autophagy levels and a decrease in cell viability, catalase, and Mn-SOD activities. Ghrelin treatment significantly attenuated CoCl2-induced hypoxic injury by decreasing cell apoptosis, LDH activity, ROS content, and Nox1 expression and increasing cell viability, autophagy levels, catalase, and Mn-SOD mRNA levels and activities. Further experiments revealed that inhibiting autophagy using 3-MA or AMPK pathway with compound C almost abrogated the induction of ghrelin in autophagy. This was associated with a decrease in cell viability and an increase in LDH activity. Our results indicate that ghrelin protected cardiac myocytes against CoCl2-induced hypoxic injury by decreasing Nox1 expression, increasing the expression and activity of endogenous antioxidant enzymes, and inducing protective autophagy in an AMPK-dependent manner. [Copyright &y& Elsevier]

Oxidative stress induces serious tissue injury in cardiovascular diseases. Salidroside, with its strong antioxidative and cytoprotective actions, is of particular interest in the development of antioxidative therapies for oxidative injury in cardiac diseases. We examined the pharmacological effects of salidroside on H9c2 rat cardiomyoblast cells under conditions of oxidative stress induced by hydrogen peroxide (H2O2) challenge. Salidroside attenuated H2O2-impaired cell viability in a concentration-dependent manner, and effectively inhibited cellular malondialdehyde production, lethal sarcolemmal disruption, cell necrosis, and apoptosis induced by H2O2 insult. Salidroside significantly augmented Akt phosphorylation at Serine 473 in the absence or presence of H2O2 stimulation; wortmannin, a specific inhibitor of PI3K, abrogated salidroside protection. Salidroside increased the intracellular mRNA expression and activities of catalase and Mn-superoxide dismutases in a PI3K-dependent manner. Our results indicated that salidroside protected cardiomyocytes against oxidative injury through activating the PI3K/Akt pathway and increasing the expression and activities of endogenous PI3K dependent antioxidant enzymes. [ABSTRACT FROM AUTHOR]

Narrow-mesoporous SiO 2 with ordered helical channels (pore size less than 10 nm) was prepared via a soft template method. Thereafter, the polyimide (PI) mixed matrix membranes (MMMs) incorporated with helical-mesoporous SiO 2 were used for CO 2 separation. Characterization results show that the formation of asymmetric helical channel structures in narrow-mesoporous SiO 2 increased the defect structures and the hydroxyl groups on the pore surface, thus enhancing the affinity between CO 2 molecules and SiO 2. Due to the stronger CO 2 capture ability, the addition of helical-mesoporous SiO 2 introduced confined mass transfer channels into the polymer matrix for facilitated transport of CO 2 , thus significantly enhancing the CO 2 separation ability of MMMs. Increasing the loading content of helical-mesoporous SiO 2 not only increased the confined channels to facilitate CO 2 transport, but also improved the CO 2 capture ability of MMMs, thus enhancing their CO 2 selectivity. The gas permeability and CO 2 /N 2 ideal selectivity calculated using the Maxwell-Wagner-Sillar model, assuming the helical-mesoporous SiO 2 as a collection of parallel helical channels, agreed well with the experimental data of MMMs at low loading content of SiO 2. When the loading content exceeded 15 wt%, the SiO 2 aggregations caused the formation of non-selective voids in membranes, significantly lowering the CO 2 /N 2 ideal selectivity. [Display omitted] • PI membranes incorporated with mesoporous SiO 2 with helical channels were fabricated. • The confined channels for CO 2 facilitated transport of were introduced into the membranes. • Increase in the confined channels in the membranes enhanced their CO 2 selectivity. • SiO 2 aggregations caused the non-selective voids and depressed the membrane performance. • The calculated gas permeation results by the MWS model agreed with the experimental data. [ABSTRACT FROM AUTHOR]

• A novel chiral-arranged TiO 2 -SiO 2 with high visible-light performance was prepared. • The relationship between chiral structure and photocatalytic activity was explore. • The asymmetric microstructures caused numerous oxygen vacancies and Ti-N bonds. • Both oxygen vacancies and Ti-N bonds promoting photocatalytic performance. • No chiral structure formed in the materials while reacting at high temperature. Aiming at exploring the relationship between photocatalysts with nanoscale chiral structures and their photocatalytic activity, we fabricated a novel chiral-arranged TiO 2 -SiO 2 mesoporous material with high visible-light absorption and photocatalytic performance. Through a soft template route using a chiral surfactant and a co-structure-directing agent, the mesoporous materials with helical-spherical depositions could form in under low reaction temperature (≤10 °C). The asymmetric helical microstructures introduced numerous oxygen vacancies and Ti-N bonds into the materials, thus significantly promoting their visible-light response and photocatalytic performance. The chiral-arranged TiO 2 -SiO 2 mesoporous material had high substantial visible-light-driven photocatalytic performance, including the degradation for rhodamine B in water and the production of hydrogen with a sacrificial reagent. The optimal removal rate of chiral-arranged TiO 2 -SiO 2 materials for rhodamine B exceeded 97% irradiated by visible light. With increasing reaction temperature, the formation of TiO 2 agglomerations could not deposit with the silica chiral frames and no chiral structure formed in the materials, thus exhibiting no visible-light response of TiO 2 -SiO 2 materials. [ABSTRACT FROM AUTHOR]