Access to Spirocyclic Oxindoles via N-Heterocyclic Carbene-Catalyzed Reactions of Enals and Oxindole-Derived α,β-Unsaturated Imines

A diastereoselective access to <b>β</b>-lactam fused spirocyclic oxindoles and related compounds bearing all carbon spiro centers is described. This N-heterocyclic carbene-catalyzed process employed challenging <b>β,β</b>-disubstituted <b>α,β</b>-unsaturated imines to react with enals

Li Electrochemical Tuning of Metal Oxide for Highly Selective CO₂ Reduction

Engineering active grain boundaries (GBs) in oxide-derived (OD) electrocatalysts is critical to improve the selectivity in CO₂ reduction reaction (CO₂RR), which is becoming an increasingly important pathway for renewable energy storage and usage. Different from traditional <i>in situ</i> electrochemical reduction under CO₂RR conditions, where some metal oxides are converted into active metallic phases but with decreased GB densities, here we introduce the Li electrochemical tuning (LiET) method to controllably reduce the oxide precursors into interconnected ultrasmall metal nanoparticles with enriched GBs. By using ZnO as a case study, we demonstrate that the LiET-Zn with freshly exposed GBs exhibits a CO₂-to-CO partial current of ∼23 mA cm^–2 at an overpotential of −948 mV, representing a 5-fold improvement from the OD-Zn with GBs eliminated during the <i>in situ</i> electro-reduction process. A maximal CO Faradaic efficiency of ∼91.1% is obtained by LiET-Zn on glassy carbon substrate. The CO₂-to-CO mechanism and interfacial chemistry are further probed at the molecular level by advanced <i>in situ</i> spectroelectrochemical technique, where the reaction intermediate of carboxyl species adsorbed on LiET-Zn surface is revealed

B‑Doped Pd Catalyst: Boosting Room-Temperature Hydrogen Production from Formic Acid–Formate Solutions

Facile production of hydrogen at room temperature is an important process in many areas including alternative energy. In this Communication, a potent boron-doped Pd nanocatalyst (Pd-B/C) is reported for the first time to boost hydrogen generation at room temperature from aqueous formic acid–formate solutions at a record high rate. Real-time ATR-IR spectroscopy is applied to shed light on the enhanced catalytic activity of B-doping and reveals that the superior activity of Pd-B/C correlates well with an apparently impeded CO_ad accumulation on its surfaces. This work demonstrates that developing new anti-CO poisoning catalysts coupled with sensitive interfacial analysis is an effective way toward rational design of cost-effective catalysts for better hydrogen energy exploitation

One Step Encapsulation of Mesenchymal Stromal Cells in PEG Norbornene Microgels for Therapeutic Actions

Cell therapies require control over the cellular response under standardized conditions to ensure continuous delivery of therapeutic agents. Cell encapsulation in biomaterials can be particularly effective at providing cells with a uniformly supportive and permissive cell microenvironment. In this study, two microfluidic droplet device designs were used to successfully encapsulate equine mesenchymal stromal cells (MSCs) into photopolymerized polyethylene glycol norbornene (PEGNB) microscale (∼100–200 μm) hydrogel particles (microgels) in a single on-chip step. To overcome the slow cross-linking kinetics of thiol–ene reactions, long dithiol linkers were used in combination with a polymerization chamber customized to achieve precise retention time for microgels while maintaining cytocompatibility. Thus, homogeneous cell-laden microgels could be continuously fabricated in a high-throughput fashion. Varying linker length mediated both the gel formation rate and material physical properties (stiffness, mass transport, and mesh size) of fabricated microgels. Postencapsulation cell viability and therapeutic indicators of MSCs were evaluated over 14 days, during which the viability remained at least 90%. Gene expression of selected cytokines was not adversely affected by microencapsulation compared to monolayer MSCs. Notably, PEGNB-3.5k microgels rendered significant elevation in FGF-2 and TGF-β on the transcription level, and conditioned media collected from these cultures showed robust promotion in the migration and proliferation of fibroblasts. Collectively, standardized MSC on-chip encapsulation will lead to informed and precise translation to clinical studies, ultimately advancing a variety of tissue engineering and regenerative medicine practices

Descriptions of self-treatment for the middle-aged and elderly in Shanxi, China

<div><p>Objectives</p><p>Self-treatment is a widespread practice among patients with common symptoms and ailments; it is necessary to explore multiple aspects of it. Notably, there is little research into self-treatment among middle-aged and elderly people, who are more likely to fall ill. Our goals are to provide a comprehensive description of self-treatment and explore associated factors with insurance utilization and expenditures among the middle-aged and elderly populations in China.</p><p>Methods</p><p>A survey was conducted in July 2016 in Shanxi, China. A stratified sampling scheme was applied to achieve representativeness. A total of 972 subjects were surveyed. Descriptive statistics, t- and Chi-squared tests, multivariate logistic regression, and multivariate linear regression were utilized.</p><p>Results</p><p>In our study, 772 (79.4%) of the surveyed subjects self-treated during the previous twelve months. Among them, 253 (32.8%) used health insurance. Subjects’ characteristics were associated with insurance utilization and expenditures for self-treatment. Total cost was positively associated with insurance utilization. The subjects with a junior high education (<i>p</i>-value < 0.001, aOR = 0.049) and senior high education (<i>p</i>-value = 0.020, aOR = 0.146) had a lower probability of using insurance. For both total costs and out-of-pocket costs, subjects who were 51 to 60 years old had lower costs. The subjects who were seriously sick and had a primary school education, as well as enterprise occupations, had higher costs. Self-treatment times were also positively associated with costs. Finally, it was found that subjects who didn’t use insurance had lower total costs.</p><p>Conclusions</p><p>The prevalence of self-treatment was high (79.4%). Some characteristics were associated with insurance utilization and expenditures in self-treatment. Our results may be helpful for policy interventions, which are needed to further improve the effectiveness of health insurance in China.</p></div

Survey locations map.

<p>Note: a. Map of China. The red area is Shanxi Province; b. Map of Shanxi Province. Taiyuan, Shuozhou, Jincheng, Jinzhong, Datong, Linfen, Lvliang, Yuncheng, and Xinzhou are presented. R V3.3.3 software, “maptools” and “ggplot2” packages were used to create this map. The relevant geographic data was downloaded from National Geomatics Center of China <a href="http://ngcc.cn/article//sjcg/mndxt/" target="_blank">http://ngcc.cn/article//sjcg/mndxt/</a> freely.</p

Logistic regression model for characteristics and insurance utilization (n = 772).

<p>Logistic regression model for characteristics and insurance utilization (n = 772).</p

One Step Encapsulation of Mesenchymal Stromal Cells in PEG Norbornene Microgels for Therapeutic Actions

Cell therapies require control over the cellular response under standardized conditions to ensure continuous delivery of therapeutic agents. Cell encapsulation in biomaterials can be particularly effective at providing cells with a uniformly supportive and permissive cell microenvironment. In this study, two microfluidic droplet device designs were used to successfully encapsulate equine mesenchymal stromal cells (MSCs) into photopolymerized polyethylene glycol norbornene (PEGNB) microscale (∼100–200 μm) hydrogel particles (microgels) in a single on-chip step. To overcome the slow cross-linking kinetics of thiol–ene reactions, long dithiol linkers were used in combination with a polymerization chamber customized to achieve precise retention time for microgels while maintaining cytocompatibility. Thus, homogeneous cell-laden microgels could be continuously fabricated in a high-throughput fashion. Varying linker length mediated both the gel formation rate and material physical properties (stiffness, mass transport, and mesh size) of fabricated microgels. Postencapsulation cell viability and therapeutic indicators of MSCs were evaluated over 14 days, during which the viability remained at least 90%. Gene expression of selected cytokines was not adversely affected by microencapsulation compared to monolayer MSCs. Notably, PEGNB-3.5k microgels rendered significant elevation in FGF-2 and TGF-β on the transcription level, and conditioned media collected from these cultures showed robust promotion in the migration and proliferation of fibroblasts. Collectively, standardized MSC on-chip encapsulation will lead to informed and precise translation to clinical studies, ultimately advancing a variety of tissue engineering and regenerative medicine practices

Multivariate linear regression of expenditure (in RMB).

<p>Multivariate linear regression of expenditure (in RMB).</p