Efficient Electron Transfer from Electron-Sponge Polyoxometalate to Single-Metal Site Metal-Organic Frameworks for Highly Selective Electroreduction of Carbon Dioxide.

In this work, by combining the superiority of polyoxometalates (POMs) and catalytic single-metal site Co of metalloporphyrin, a series of mixed-valence POM-based metal-organic frameworks (MOFs) composites is synthesized by a post-modification method. The electron-transfer property of POM@PCN-222(Co) composite is significantly enhanced owing to the directional electron-transfer from POM to single-metal site Co in PCN-222(Co). In particular, H-POM@PCN-222(Co) gives a high Faradaic efficiency of 96.2% for electroreduction of CO2 into CO and good stability over 10 h. DFT calculations confirm that the directional electron transfer, which accelerates the multi-electron transfer from the electrode to active single-metal site Co, enriches the electron density of the Co center, and ultimately reduces the energy of the rate-determining step, thus increasing the catalytic activity of CO2 reduction reaction (CO2 RR). This work therefore suggests some new insight for the design of efficient electrocatalysts for CO2 RR.

Efficacy of acupuncture based on acupoint combination theory for irritable bowel syndrome: a study protocol for a multicenter randomized controlled trial.

BACKGROUND: Irritable bowel syndrome (IBS) is a chronic gastrointestinal disorder characterized by abdominal pain, diarrhea or constipation, and changes in defecation patterns. No organic disease is found to explain these symptoms by routine clinical examination. This study aims to investigate the efficacy and safety of acupuncture therapy for IBS patients compared with those of conventional treatments. We also aim to identify the optimal acupoint combination recommended for IBS and to clarify the clinical advantage of the "multiacupoint co-effect and synergistic effect." METHODS AND ANALYSIS: A total of 204 eligible patients who meet the Rome IV criteria for IBS will be randomly stratified into acupuncture group A, acupuncture group B, or the control group in a 1:1:1 ratio with a central web-based randomization system. The prespecified acupoints used in the control group will include bilateral Tianshu (ST25), Shangjuxu (ST37), Neiguan (PC6), and Zusanli (ST36). The prespecified acupoints used in experimental group A will include bilateral Tianshu (ST25), Shangjuxu (ST37), and Neiguan (PC6). The prespecified acupoints used in experimental group B will include bilateral Tianshu (ST25), Shangjuxu (ST37), and Zusanli (ST36). Each patient will receive 12 acupuncture treatments over 4 weeks and will be followed up for 4 weeks. The primary outcome is the IBS-Symptom Severity Scale (IBS-SSS) score. The secondary outcomes include the Bristol Stool Form Scale (BSFS), Work and Social Adjustment Score (WSAS), IBS-Quality of Life (IBS-QOL), Self-Rating Anxiety Scale (SAS), and Self-Rating Depression Scale (SDS) scores. Both the primary outcome and the secondary outcome measures will be collected at baseline, at 2 and 4 weeks during the intervention, and at 6 weeks and 8 weeks after the intervention. ETHICS AND DISSEMINATION: The entire project has been approved by the ethics committee of the Beijing University of Chinese Medicine (2020BZYLL0903). DISCUSSION: This is a multicenter randomized controlled trial for IBS in China. The findings may shed light on the efficacy of acupuncture as an alternative to conventional IBS treatment. The results of the trial will be disseminated in peer-reviewed publications. TRIAL REGISTRATION: Chinese Clinical Trials Register ChiCTR2000041215 . First registered on 12 December 2020. http://www.chictr.org.cn/ .

Superhydrophobic SERS chip based on a Ag coated natural taro-leaf.

Surface-enhanced Raman spectroscopy (SERS) substrates based on plasmonic nanostructures allow for label-free and fingerprinting molecular detection with ultrahigh sensitivity and selectivity, but their complicated and high-cost fabrication remains a challenge for practical applications and commercialization of SERS technology. Herein, we developed a facile and low-cost natural SERS substrate based on silver coated taro leaf (Taro-leaf@Ag) that exhibits ordered micro-papillae and secondary crossed nanoplates. The micro-papillae exhibited superior superhydrophobicity for analyte enrichment and the secondary crossed nanoplates provided rich SERS hot spots, which together lead to highly sensitive SERS detection with a detection limit as low as 10(-8) M. Moreover, the crossed nanoplates were uniformly distributed such that reproducible SERS measurements with a 9.7% variation over 1274 spectra was achieved. The high SERS sensitivity and reproducibility as well as the facile and low-cost fabrication make the Taro-leaf@Ag a promising natural SERS substrate for future practical biochemical detection methods.

Effect of heparin on production of transforming growth factor (TGF)-beta1 and TGF-beta1 mRNA expression by human normal skin and hyperplastic scar fibroblasts.

Heparin affects both dermal fibroblast proliferation and collagen and may mediate these effects by altering the levels of transforming growth factor-beta1 (TGF-beta1) production and TGF-beta1 mRNA expression as a wound healing modulator. The purpose of this study is to probe the effect of heparin on TGF-beta1 and TGF-beta1 mRNA production by human normal skin and hyperplastic scar fibroblasts. This research investigates the effect of heparin on TGF-beta1 and TGF-beta1 mRNA production by human normal skin and hyperplastic scar fibroblasts with exposure to 0 microg/mL, 100 microg/mL, 300 microg/mL, or 600 microg/mL heparin for 24, 48, 72, or 96 hours in a serum-free in vitro model. Levels of TGF-beta1 in the supernatants and TGF-beta1 mRNA expression of fibroblasts were determined by enzyme-linked immunosorbent assay (ELISA) and real time RT-PCR, respectively. Heparin (300 microg/mL and 600 microg/mL) stimulated TGF-beta1 production by normal skin (26% to 83%) and hyperplastic scar fibroblasts (63% to 85%), with statistical significance (P < 0.05) at various time points. Heparin (300 microg/mL and 600 microg/mL) also stimulated TGF-beta1 mRNA expression by normal skin (12% to 53%) and hyperplastic scar fibroblasts (33% to 52%), with statistical significance (P < 0.05) at various time points. These effects of heparin on normal skin and hyperplastic scar fibroblasts may have implications for hyperplastic scar formation and wound healing in vivo.