The interaction between 20-hydroxyecdysone and AMPK through PI3K activation in Chinese mitten crab, Eriocheir sinensis.

In crustaceans, the steroid hormone 20-hydroxyecdysone (20E) initiates molting, and the molting process is also regulated by energy metabolism. AMPK is an energy sensor and plays a critical role in systemic energy balance. Here, the regulatory mechanism in the interaction between 20E and AMPK was investigated in Chinese mitten crab, Eriocheir sinensis. The results showed that the 20E concentration and the mRNA expression levels of 20E receptors in hepatopancreas were down-regulated post AMPK activator (AICAR) treatment, and were up-regulated after AMPK inhibitor (Compound C) injection in crabs. Besides, the molt-inhibiting hormone (MIH) gene expression in eyestalk showed the opposite patterns in response to the AICAR and Compound C treatment, respectively. Further investigation found that there was a significant reduction in 20E concentration post PI3K inhibitor (LY294002) treatment, and the phosphorylation level of PI3K was increased in hepatopancreas after AMPK inhibitor injection. On the other hand, the positive regulation of PI3K-mediated activation of AMPK was also observed, the phosphorylation levels of AMPKα, AMPKß and PI3K in hepatopancreas were significantly increased post 20E injection. In addition, the phosphorylation levels of AMPKα and AMPKß induced by 20E were decreased after the injection of PI3K inhibitor. Taken together, these results suggest that the regulatory cross-talk between 20E and AMPK is likely to act through PI3K pathway in E. sinensis, which appeared to be helpful for a better understanding in molting regulation.

"Have to do" or "willing to do": Examining the relationship between self-control and academic emotions using experience sampling method.

The purpose of this study was to examine the antecedents of academic emotions among university students through real-time and multilevel analyses. We explored the link between state self-control and academic emotions, the influence of self-determination on the relationship between them, and the moderating role of trait self-control. The data was collected over seven consecutive days during which university students (N = 155) completed smartphone questionnaires. Data was organized into hierarchical two-level structures, where situations (Level 1) nested within individuals (Level 2). The results showed that positive emotions were negatively predicted by state self-control while negative emotions were positively predicted by state self-control. Moreover, state self-control under low self-determination was a significant negative predictor of positive emotions, whereas high self-determination had no predictive effect on positive emotions. The relationship between self-determination and negative emotions was further moderated by trait self-control. The limitations of this study and future research directions are also discussed.

Detecting explosive molecules from nanoliter solution: A new paradigm of SERS sensing on hydrophilic photonic crystal biosilica.

We demonstrate a photonic crystal biosilica surface-enhanced Raman scattering (SERS) substrate based on a diatom frustule with in-situ synthesized silver nanoparticles (Ag NPs) to detect explosive molecules from nanoliter (nL) solution. By integrating high density Ag NPs inside the nanopores of diatom biosilica, which is not achievable by traditional self-assembly techniques, we obtained ultra-high SERS sensitivity due to dual enhancement mechanisms. First, the hybrid plasmonic-photonic crystal biosilica with three dimensional morphologies was obtained by electroless-deposited Ag seeds at nanometer sized diatom frustule surface, which provides high density hot spots as well as strongly coupled optical resonances with the photonic crystal structure of diatom frustules. Second, we discovered that the evaporation-driven microscopic flow combined with the strong hydrophilic surface of diatom frustules is capable of concentrating the analyte molecules, which offers a simple yet effective mechanism to accelerate the mass transport into the SERS substrate. Using the inkjet printing technology, we are able to deliver multiple 100pico-liter (pL) volume droplets with pinpoint accuracy into a single diatom frustule with dimension around 30µm×7µm×5µm, which allows for label-free detection of explosive molecules such as trinitrotoluene (TNT) down to 10-10M in concentration and 2.7×10-15g in mass from 120nL solution. Our research illustrates a new paradigm of SERS sensing to detect trace level of chemical compounds from minimum volume of analyte using nature created photonic crystal biosilica materials.

Optofluidic sensing from inkjet-printed droplets: the enormous enhancement by evaporation-induced spontaneous flow on photonic crystal biosilica.

Novel transducers for detecting an ultra-small volume of an analyte solution play pivotal roles in many applications such as chemical analysis, environmental protection and biomedical diagnosis. Recent advances in optofluidics offer tremendous opportunities for analyzing miniature amounts of samples with high detection sensitivity. In this work, we demonstrate enormous enhancement factors (106-107) of the detection limit for optofluidic analysis from inkjet-printed droplets by evaporation-induced spontaneous flow on photonic crystal biosilica when compared with conventional surface-enhanced Raman scattering (SERS) sensing using the pipette dispensing technology. Our computational fluid dynamics simulation has shown a strong recirculation flow inside the 100 picoliter droplet during the evaporation process due to the thermal Marangoni effect. The combination of the evaporation-induced spontaneous flow in micron-sized droplets and the highly hydrophilic photonic crystal biosilica is capable of providing a strong convection flow to combat the reverse diffusion force, resulting in a higher concentration of the analyte molecules at the diatom surface. In the meanwhile, high density hot-spots provided by the strongly coupled plasmonic nanoparticles with photonic crystal biosilica under a 1.5 µm laser spot are verified by finite-difference time domain simulation, which is crucial for SERS sensing. Using a drop-on-demand inkjet device to dispense multiple 100 picoliter analyte droplets with pinpoint accuracy, we achieved the single molecule detection of Rhodamine 6G and label-free sensing of 4.5 × 10-17 g trinitrotoluene from only 200 nanoliter solution.

Gastrodin ameliorates spinal cord injury via antioxidant and anti-inflammatory effects.

Spinal cord injury (SCI) is one of the most severe traumatic injuries that results in dysfunction of limbs and trunk below the damaged section. Recent studies have shown that gastrodin (GAS) could improve the recovery of SCI. In the current study, we aimed to examine the possible mechanism underlying the effect of GAS on recovery of SCI in rats. In rats with SCI, GAS improved locomotor functions and decreased permeability of blood-spinal cord barrier, as illustrated by increase of Basso-Beattie-Bresnahan scores and decrease of Evans blue leakage. In addition, GAS inhibited inflammation, as evidenced by decrease of proinflammatory cytokines, including tumor necrosis factor α (TNFα) and interleukin-1ß (IL-1ß) in rats following SCI. Moreover, increase of TBARS content and decrease of glutathione (GSH) content and superoxide dismutase (SOD) activities in SCI rats were inhibited by GAS. Furthermore, GAS enhanced mRNA expression of nuclear factor (erythroid-derived 2)-like 2 (Nrf2), catalytic subunit of γ-glutamylcysteine ligase (GCLc) and modified subunit of γ-glutamylcysteine ligase (GCLm). The data suggested that GAS may promote the recovery of SCI through the enhancement of Nrf2-GCLc/GCLm signaling pathway, and subsequent improvement of oxidative stress and inflammation, resulting in decrease of permeability of BSCB and improved recovery of locomotor function in rats with SCI. The results have provided novel insights into GAS-related therapy of SCI and associated neurodegenerative diseases.