Endurance exercise accelerates myocardial tissue oxygenation recovery and reduces ischemia reperfusion injury in mice

Exercise training offers cardioprotection against ischemia and reperfusion (I/R) injury. However, few essential signals have been identified to underscore the protection from injury. In the present study, we hypothesized that exercise-induced acceleration of myocardial tissue oxygenation recovery contributes to this protection. C57BL/6 mice (4 weeks old) were trained on treadmills for 45 min/day at a treading rate of 15 m/min for 8 weeks. At the end of 8-week exercise training, mice underwent 30-min left anterior descending coronary artery occlusion followed by 60-min or 24-h reperfusion. Electron paramagnetic resonance oximetry was performed to measure myocardial tissue oxygenation. Western immunoblotting analyses, gene transfection, and myography were examined. The oximetry study demonstrated that exercise markedly shortened myocardial tissue oxygenation recovery time following reperfusion. Exercise training up-regulated Kir6.1 protein expression (a subunit of ATP-sensitive K(+)channel on vascular smooth muscle cells, VSMC sarc-K(ATP)) and protected the heart from I/R injury. In vivo gene transfer of dominant negative Kir6.1AAA prolonged the recovery time and enlarged infarct size. In addition, transfection of Kir6.1AAA increased the stiffness and reduced the relaxation capacity in the vasculature. Together, our study demonstrated that exercise training up-regulated Kir6.1, improved tissue oxygenation recovery, and protected the heart against I/R injury. This exercise-induced cardioprotective mechanism may provide a potential therapeutic intervention targeting VSMC sarc-K(ATP) channels and reperfusion recovery

Precise Measurements of Branching Fractions for Ds+D_s^+ Meson Decays to Two Pseudoscalar Mesons

We measure the branching fractions for seven $D_{s}^{+}$ two-body decays to pseudo-scalar mesons, by analyzing data collected at $\sqrt{s}=4.178\sim4.226$ GeV with the BESIII detector at the BEPCII collider. The branching fractions are determined to be $\mathcal{B}(D_s^+\to K^+\eta^{\prime})=(2.68\pm0.17\pm0.17\pm0.08)\times10^{-3}$, $\mathcal{B}(D_s^+\to\eta^{\prime}\pi^+)=(37.8\pm0.4\pm2.1\pm1.2)\times10^{-3}$, $\mathcal{B}(D_s^+\to K^+\eta)=(1.62\pm0.10\pm0.03\pm0.05)\times10^{-3}$, $\mathcal{B}(D_s^+\to\eta\pi^+)=(17.41\pm0.18\pm0.27\pm0.54)\times10^{-3}$, $\mathcal{B}(D_s^+\to K^+K_S^0)=(15.02\pm0.10\pm0.27\pm0.47)\times10^{-3}$, $\mathcal{B}(D_s^+\to K_S^0\pi^+)=(1.109\pm0.034\pm0.023\pm0.035)\times10^{-3}$, $\mathcal{B}(D_s^+\to K^+\pi^0)=(0.748\pm0.049\pm0.018\pm0.023)\times10^{-3}$, where the first uncertainties are statistical, the second are systematic, and the third are from external input branching fraction of the normalization mode $D_s^+\to K^+K^-\pi^+$. Precision of our measurements is significantly improved compared with that of the current world average values

Repression of the genome organizer SATB1 in regulatory T cells is required for suppressive function and inhibition of effector differentiation

Regulatory T cells (T(reg) cells) are essential for self-tolerance and immune homeostasis. Lack of effector T cell (T(eff) cell) function and gain of suppressive activity by T(reg) cells are dependent on the transcriptional program induced by Foxp3. Here we report that repression of SATB1, a genome organizer that regulates chromatin structure and gene expression, was crucial for the phenotype and function of T(reg) cells. Foxp3, acting as a transcriptional repressor, directly suppressed the SATB1 locus and indirectly suppressed it through the induction of microRNAs that bound the SATB1 3' untranslated region. Release of SATB1 from the control of Foxp3 in T(reg) cells caused loss of suppressive function, establishment of transcriptional T(eff) cell programs and induction of T(eff) cell cytokines. Our data support the proposal that inhibition of SATB1-mediated modulation of global chromatin remodeling is pivotal for maintaining T(reg) cell functionality.Marc Beyer... Timothy Sadlon...Simon C Barry... et al

Synthesis and antibacterial activity of modified ε-polylysine

In this paper, Ugi reaction was used to synthesize the modified polylysine (M-ε-PL) in two steps, and OD value was measured by ultraviolet spectrophotometer to determine the inhibitory rate of M-ε-PL in different concentrations of Escherichia coli and Staphylococcus aureus. The results showed that the antibacterial effect was better with the increase of concentration of M-ε-PL. Among them, 20 mg/mL M-εPL had better bacteriostatic effect on E. coli and S. aureus. The antibacterial rate was 70% and 44%

The Effects of Heteroatoms Si and S on Tuning the Optical Properties of Rhodamine- and Fluorescein-Based Fluorescence Probes: A Theoretical Analysis

The effects of the incorporated heteroatoms Si and S on tuning the optical properties of rhodamine-and fluorescein-based fluorescence probes is investigated using DFT and time-dependent DFT with four different functionals. As previously proposed, the large redshift (90 nm) produced by a Si atom in both the absorption and emission spectra can be attributed to the sigma*-pi* conjugation between the sigma* orbital of the Si atom and the pi* orbital of the adjacent carbon atoms. However, the presence of a Si atom does not alter the fluorescence quenching mechanism of the nonfluorescent forms of the investigated compounds. For the first time, these theoretical results indicate that the n orbital of the S atom plays an important role in determining the optical properties of the nonfluorescent form of rhodamine-based fluorescence probes. It alters the fluorescence quenching mechanism by lowering the energy of the dark n pi* state, which is due to breakage of the C10-S52 bond upon photoexcitation

Ultrafast Charge Separation for Full Solar Spectrum-Activated Photocatalytic H-2 Generation in a Black Phosphorus-Au-CdS Heterostructure

Two-dimensional layered black phosphorus (BP) with a tunable band gap of 0.3-2.0 eV has received great interest in broad-spectrum-active photocatalysis, but rapid charge recombination limits its potential applications. Herein, we report that BP quantum dots (QDs) work as active photosensitizer in a ternary heterostructure consisting of BP QDs, Au nanorods (NRs), and CdS nanowires (NWs), which efficiently photocatalytically generates H-2 at full solar spectrum, especially in the near-infrared (NIR) region. The superior performance of the BP-Au-CdS heterostructure arises from the overall photoabsorption contribution, the dual role (electron relay and plasmonic electron donor) of Au NRs, as well as the appropriate band alignment and strong coupling between the three components. Tracking the electron and hole transfers via femtosecond transient absorption spectroscopy shows a unidirectional electron flow from BP to Au and then to CdS, which has been achieved by the high conduction band level of BP, the well-harnessed work function match in BP-Au, and the well-established Schottky barrier in Au-CdS heterojunction

Black phosphorus-CdS-La2Ti2O7 ternary composite: Effective noble metal-free photocatalyst for full solar spectrum activated H-2 production

Wide-bandgap semiconductor photocatalysts such as La2Ti2O7 (LTO) are stable but can only work under ultraviolet (UV) light, while narrow-bandgap semiconductor photocatalysts such as CdS and black phosphorus (BP) with broad-wavelength range absorption generally have low stability and high electron-hole pairs recombination rate. In this work, ternary heterostructure composing of BP quantum dots (QDs), CdS nanoparticles (NPs) and LTO nanosteps (NSP) is developed for the first time to make full use of their respective advantages, which offers a promising approach to achieving desired stability and solar energy harvesting. As an effective noble metal-free photocatalyst, BP-CdS-LTO composite generates H-2 from Na2S/Na2SO3 aqueous solution with a rate of 0.96 mmol g(-1) h(-1) under solar light irradiation, and 0.26 mmol g(-1) h(-1) in the near-infrared (NIR) range. In this system, BP serves as a NIR photosensitizer; CdS not only contributes to visible light absorption but also bonds with BP to promote the transmission of photogenerated charge carriers; LTO absorbs UV light as well as provides reaction sites for photoinduced electrons. Femtosecond transient absorption spectroscopy is used to elucidate the kinetics of the injection of photogenerated electrons from BP QDs to CdS NPs and finally to LTO. This work provides deep insight into charge transfer between semiconductors with different band alignments, which can open a new avenue for more rationally designing heterostuctured photocatalysts for H-2 production

Structural Hawkes Processes for Learning Causal Structure from Discrete-Time Event Sequences

Learning causal structure among event types from discrete-time event sequences is a particularly important but challenging task. Existing methods, such as the multivariate Hawkes processes based methods, mostly boil down to learning the so-called Granger causality which assumes that the cause event happens strictly prior to its effect event. Such an assumption is often untenable beyond applications, especially when dealing with discrete-time event sequences in low-resolution; and typical discrete Hawkes processes mainly suffer from identifiability issues raised by the instantaneous effect, i.e., the causal relationship that occurred simultaneously due to the low-resolution data will not be captured by Granger causality. In this work, we propose Structure Hawkes Processes (SHPs) that leverage the instantaneous effect for learning the causal structure among events type in discrete-time event sequence. The proposed method is featured with the minorization-maximization of the likelihood function and a sparse optimization scheme. Theoretical results show that the instantaneous effect is a blessing rather than a curse, and the causal structure is identifiable under the existence of the instantaneous effect. Experiments on synthetic and real-world data verify the effectiveness of the proposed method.Comment: Accepted by IJCAI 202

Autotutor 2013: Conversation-based online intelligent tutoring system with rich media (interactive event)

AutoTuto 2013 is an advanced version of the intelligent tutoring system, proven to be effective in empirical tests. AutoTutor 2013 is an agent-based online system with rich media among multiple agents and learners. AutoTutor delivers knowledge by means of multi-turns of conversions with the assist of the comprehensive media technology, including images, diagrams, audios, videos and other interactive presentations developed by Media Semantics Character Builder program. © 2013 Springer-Verlag Berlin Heidelberg