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Cardiac tissue engineering using biomaterials with or without combination of stem cell therapy offers a new option for repairing infarcted heart. However, the bioactivity of biomaterials remains to be optimized because currently available biomaterials do not mimic the biochemical components as well as the structural properties of native myocardial extracellular matrix. Here we hypothesized that human heart valve-derived scaffold (hHVS), as a clinically relevant novel biomaterial, may provide the proper microenvironment of native myocardial extracellular matrix for cardiac repair. In this study, human heart valve tissue was sliced into 100 μm tissue sheet by frozen-sectioning and then decellularized to form the hHVS. Upon anchoring onto the hHVS, post-infarct murine BM c-kit+ cells exhibited an increased capacity for proliferation and cardiomyogenic differentiation in vitro. When used to patch infarcted heart in a murine model of myocardial infarction, either implantation of the hHVS alone or c-kit+ cell-seeded hHVS significantly improved cardiac function and reduced infarct size; while c-kit+ cell-seeded hHVS was even superior to the hHVS alone. Thus, we have successfully developed a hHVS for cardiac repair. Our in vitro and in vivo observations provide the first clinically relevant evidence for translating the hHVS-based biomaterials into clinical strategies to treat myocardial infarction. [ABSTRACT FROM AUTHOR]

From January 2010 to December 2016, 1616 consecutive patients who underwent isolated coronary artery bypass grafting (CABG) were evaluated for their predicted mortality according to the online Sino System for Coronary Operative Risk Evaluation (SinoSCORE), European System for Cardiac Operative Risk Evaluation II (EuroSCORE II) and Society of Thoracic Surgeons (STS) risk evaluation system. The calibration and discrimination in the total and in the subsets were assessed by the Hosmer-Lemeshow (H-L) statistics and by the C statistics respectively, to evaluate the efficiency of the three risk evaluation systems. The realized mortality was 1.92% (31/1616). The predictive mortality of SinoSCORE, EuroSCORE II and STS risk evaluation system were 1.35%, 1.74% and 1.05%, respectively. SinoSCORE achieved best discrimination. When grouping by risk, SinoSCORE also achieved the best discrimination in high-risk group, followed by STS risk evaluation system and EuroSCORE II while SinoSCORE and EuroSCORE II had excellent performance in low-risk group. In terms of calibration, SinoSCORE, EuroSCORE II and STS risk evaluation system all achieved positive calibrations (H-L: P > 0.05) in the overall population and grouped subsets. SinoSCORE achieved good predictive efficiency in East China patients undergoing isolated CABG and showed no compromise when compared with EuroSCORE II and STS risk evaluation system.

We here study explosive synchronization transitions and network activity propagation in networks of coupled neurons to provide a new understanding of the relationship between network topology and explosive dynamical transitions as in epileptic seizures and their propagations in the brain. We model local network motifs and configurations of coupled neurons and analyze the activity propagations between a group of active neurons to their inactive neuron neighbors in a variety of network configurations. We find that neuronal activity propagation is limited to local regions when network is highly clustered with modular structures as in the normal brain networks. When the network cluster structure is slightly changed, the activity propagates to the entire network, which is reminiscent of epileptic seizure propagation in the brain. Finally, we analyze intracranial electroencephalography (IEEG) recordings of a seizure episode from a epilepsy patient and uncover that explosive synchronization-like transition occurs around the clinically defined onset of seizure. These findings may provide a possible mechanism for the recurrence of epileptic seizures, which are known to be the results of aberrant neuronal network structure and/or function in the brain.

Gradient Mn-La-Pt catalysts with three-layered structure of manganese dioxide (MnO 2 ), lanthanum oxide (La 2 O 3 ), and Platinum (Pt) for Li-O 2 battery are prepared in this study. The mass ratio of the catalysts is respectively 5:2:3, 4:2:4, and 3:2:5 (MnO 2 : La 2 O 3 : Pt) which is start from the side of the electrolyte. The relationship between morphology structure and electrochemical performance of gradient catalyst is investigated by energy dispersive spectrometry and constant current charge/discharge test. The Li-O 2 battery based on gradient Mn-La-Pt catalysts shows high discharge specific capacity (2707 mAh g -1 ), specific energy density (8400 Wh kg -1 ) and long cycle life (56 cycles). The improvement of the Li-O 2 battery discharge capacity is attributed to the gradient distribution of MnO 2 and Pt and the involvement of La 2 O 3 that can improve the energy density of the battery. More important, this work will also provide new ideas and methods for the research of other metal-air battery.

Deep sub-wavelength ripples (DSRs) and near sub-wavelength ripples (NSRs) with uniform periods of ~160 nm and ~660 nm generated at the MoS2-vacuum interface is reported for the first time by the processing of femtosecond laser (800 nm, 120 fs, 1 kHz) in this paper. The DSRs and NSRs formation fluence thresholds are experimentally determined as 160 mJ/cm(2) and 192 mJ/cm(2), respectively. In addition, the ripple period is insensitive to the pulse number. Moreover, Raman analyses show that the MoS2 lattice in the irradiated area does not exhibit oxidation at room environment and the crystalline representation is well preserved in NSRs region. We attribute our result to the joint interactions of the spallation and sublimation of layered MoS2 together with the laser induced surface plasmon polaritons and propose an explanation to the threshold dependence of the ripple period. Our study provides some insights for ultrafast laser-matter interactions and indicates a simple effective method for future nano-fabrication of MoS2.

Although it is well known that there are mutation hot spots in mtDNA, whether there are damage hot spots remain elusive. In this study, the regional DNA damage of mitochondrial genome after ionizing radiation was determined by real-time quantitative PCR. The mtDNA damage level was found to be dose-dependent and regional unequal. The control region was the most susceptible region to oxidative damage. GGG, as an typical hole trap during charge transport, was found to be disproportionally enriched in the control region. A total of 107 vertebrate mitochondrial genomes were then analyzed to testify whether the GGG enrichment in control region was evolutionary conserved. Surprisingly, the triple G enrichment can be observed in most of the homeothermal animals, while the majority of heterothermic animals showed no triple G enrichment. These results indicated that the triple G enrichment in control region was related to the mitochondrial metabolism during evolution.