Exploration of high‐efficiency, economical, and ultrastable electrocatalysts for the oxygen reduction reaction (ORR) to substitute precious Pt is of great significance in electrochemical energy conversion devices. Single‐atom catalysts (SACs) have sparked tremendous interest for their maximum atom‐utilization efficiency and fascinating properties. Therefore, the development of effective synthetic methodology toward SACs becomes highly imperative yet still remains greatly challenging. Herein, a reliable SiO2‐templated strategy is elaborately designed to synthesize atomically dispersed Fe atoms anchored on N‐doped carbon nanospheres (denoted as Fe–N–C HNSs) using the cheap and sustainable biomaterial of histidine (His) as the N and C precursor. By virtue of the numerous atomically dispersed Fe–N4 moieties and unique spherical hollow architecture, the as‐fabricated Fe–N–C HNSs exhibit excellent ORR performance in alkaline medium with outstanding activity, high long‐term stability, and superior tolerance to methanol crossover, exceeding the commercial Pt/C catalyst and most previously reported non‐precious‐metal catalysts. This present synthetic strategy will provide new inspiration to the fabrication of various high‐efficiency single‐atom catalysts for diverse applications.
Mesenchymal stem cells (MSCs) have been reported to hold promise to accelerate the wound-healing process in diabetic foot ulcer (DFU) due to the multilineage differentiation potential. Hence, this study intended to explore the wound healing role of MSC-derived exosomes containing long noncoding RNA (lncRNA) H19 in DFU. lncRNA H19 was predicated to bind to microRNA-152-3p (miR-152-3p), which targeted phosphatase and tensin homolog (PTEN) deleted on chromosome ten. Fibroblasts in DFU samples exhibited highly expressed miR-152-3p and poorly expressed lncRNA H19 and PTEN, along with an activated phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K)/protein kinase B (Akt1) signaling pathway. The fibroblasts were cocultured with lncRNA H19-transfected MSCs and MSC-derived exosomes to assess the effect of the lncRNA H19/miR-152-3p/PTEN axis on the biological activities and inflammation in fibroblasts. Mouse models of DFU were developed by streptozotocin, which was injected with MSC-derived exosomes overexpressing lncRNA H19. lncRNA H19 in MSCs was transferred through exosomes to fibroblasts, the mechanism of which improved wound healing in DFU, corresponded to promoted fibroblast proliferation and migration, as well as suppressed apoptosis and inflammation. Wound healing in mice with DFU was facilitated following the injection of MSC-derived exosomes overexpressing lncRNA H19. Taken together, MSC-derived exosomal lncRNA H19 prevented the apoptosis and inflammation of fibroblasts by impairing miR-152-3p-mediated PTEN inhibition, leading to the stimulated wound-healing process in DFU.
The electrochromic property and device construction of a triphenylamine-based oriented two-dimensional covalent organic framework (2D COF) film on indium tin oxide (ITO) coated glass was reported. The characterization of the 2D COF3PA‑TT film revealed that the film was uniform, with good crystallinity, and oriented with its 2D plane parallel to the substrate. For the first time, the electrochromic properties of 2D COF3PA‑TT film were studied. 2D COF3PA‑TT film on ITO exhibited reversible color transition between deep red and dark brown during redox process. Spectroelectrochemical experiments revealed color changes in the absorption spectra of 2D COF3PA‑TT film in the visible and near-infrared regions and showed the characteristics of intervalence charge transfer. The quasi-solid-state electrochromic device was prepared based on the COF3PA‑TT film, and it exhibited moderate performance and stability in the near-infrared region.
A Kagome structure covalent organic framework (COF) film with three‐state NIR electrochromic properties was designed and synthesized. The COFTPDA‐PDA film is composed of hexagonal nanosheets with high crystallinity and has three reversible color states at different applied potentials. It has high absorption spectra changes in the NIR region, ascribed to the strong intervalence charge transfer (IVCT) interaction of the Class III mixed‐valence systems of the conjugated triphenylamine species. The film showed sub‐second response time (1.3 s for coloring and 0.7 s for bleaching at 1050 nm) and long retention time in the NIR region. COFTPDA‐PDA film shows superior NIR electrochromic properties in term of response time and stability, attributed to the highly ordered porous structure and the π–π stacking structure of the COFTPDA‐PDA architecture. The COFTPDA‐PDA film was applied in mimicking a flip‐flop logic gate with optical memory function.
Aberrant expression of long noncoding RNA (lncRNA) H19 and microRNA (miR)-29b has been implicated in the complications of diabetes mellitus (DM). As a common and important complication of DM, diabetic foot ulcer (DFU) is characterized by high incidence and poor prognosis. Herein, we explored the role of lncRNA H19 in wound healing of DFU. Differentially expressed DM-related lncRNAs were initially screened by microarray data analysis. DFU models were then induced in DM mouse models. The functional role and interaction of lncRNA H19, miR-29b and FBN1 in DFU were subsequently determined by examining the proliferation, migration, and apoptosis of fibroblasts after silencing H19, inhibiting or overexpressing miR-29b and FBN1. According to microarray-based analysis, lncRNA H19 was upregulated in DM. In the ulcerative edge tissues of DFU, high expression of lncRNA H19 and FBN1 and low expression of miR-29b were observed. FBN1 was identified to be a target gene of miR-29b. LncRNA H19 could competitively bind to miR-29b, and then, inhibited its expression, which consequently upregulating FBN1. Silencing of lncRNA H19 led to inhibited proliferation, migration, and enhanced apoptosis of fibroblasts, accompanied by downregulated FBN1 but upregulated miR-29b, which diminished the expression of TGF-β1, Smad3, FN, and Col-1 and reduced extracellular matrix accumulation. Altogether, upregulation of lncRNA H19 can elevate the expression of FBN1 through competitively binding to miR-29b, which enhances the proliferation, migration, and inhibits apoptosis of fibroblasts, thus facilitating the wound healing of DFU.
This study aimed to quantitatively evaluate the predictive value of brachial pulse pressure and cardiovascular or all-cause mortality in the general population based on prospective observational studies by conducting a meta-analysis. Only prospective observational studies investigating baseline brachial pulse pressure and cardiovascular or all-cause mortality risk were selected from PubMed and Embase databases until July 2013. Fourteen studies involving 510,456 participants were analyzed. Pooled risk ratio (RR) of cardiovascular and all-cause mortality for the highest vs lowest brachial pulse pressure category was 1.80 (95% confidence interval [CI], 1.49-2.17) and 1.32 (95% CI, 1.23-1.41), respectively. Pooled RR of cardiovascular and all-cause mortality per 10 mm Hg pulse pressure increment was 1.13 (95% CI, 1.10-1.17) and 1.09 (95% CI, 1.07-1.11), respectively. Wide brachial pulse pressure is associated with greater risk of cardiovascular and all-cause mortality. However , more well-designed studies specifically on age and sex are needed to further confirm these findings. J Clin Hyper-tens (Greenwich). 2014;16:678-685. ª 2014 Wiley Periodicals , Inc. Cardiovascular disease (CVD) is the leading cause of mortality and a primary contributor to the burden of disease worldwide. 1 Hypertension is one of the modi-fiable risk factors for CVD mortality and accounts for up to 30% of deaths in the world. 2 Brachial pulse pressure (PP) is defined as the difference between systolic blood pressure (SBP) and diastolic blood pressure (DBP) at the brachial level. Increasing attention has focused on the role of different blood pressure (BP) components as predictors for CVD and death. 3,4 Some evidence suggests that wide PP is a risk factor for cardiovascular (CV) or all-cause mortality. 5-16 However, conflicting reports still exist. 17-19 These inconsistent results could be partly explained by PP simply being associated with mortality, not a causative factor. PP is higher after age 50 mainly because the trend of DBP gets lower and SBP gets higher with age. 20,21 Moreover, there is a lack of accurate information concerning the real risk of mortality in the various study populations. Apart from PP, other BP components such as SBP, DBP, and mean arterial pressure (MAP) were also used to predict mortality in the same studies. 6,8-10,12,14,16,17 Large artery stiffness contributes to wide PP. 22 Wide PP is linked to higher levels of the inflammatory state. 23 These findings suggest that both wide PP and inflammatory state share the common risk factor for CVD and thereby increase the risk of mortality. To the best of our knowledge, no previous meta-analysis has been performed to estimate the magnitude between brachial PP and CV or all-cause mortality risk in the general population. Therefore, we conducted this meta-analysis using prospective observational studies to quantitatively assess the baseline brachial PP and risk of CV or all-cause mortality in the general population. MATERIALS AND METHODS Search Strategy This study was carrie...
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