RESUMEN
To reach a carbon-neutral future, electrochemical CO2 reduction reaction (eCO2RR) has proven to be a strong candidate for the next-generation energy system. Among potential materials, single-atom catalysts (SACs) serve as a model to study the mechanism behind the reduction of CO2 to CO, given their well-defined active metal centers and structural simplicity. Moreover, using metal-organic frameworks (MOFs) as supports to anchor and stabilize central metal atoms, the common concern, metal aggregation, for SACs can be addressed well. Furthermore, with their turnability and designability, MOF-derived SACs can also extend the scope of research on SACs for the eCO2RR. Herein, we synthesize sulfurized MOF-derived Mn SACs to study effects of the S dopant on the eCO2RR. Using complementary characterization techniques, the metal moiety of the sulfurized MOF-derived Mn SACs (MnSA/SNC) is identified as MnN3S1. Compared with its non-sulfur-modified counterpart (MnSA/NC), the MnSA/SNC provides uniformly superior activity to produce CO. Specifically, a nearly 30% enhancement of Faradaic efficiency (F.E.) in CO production is observed, and the highest F.E. of approximately 70% is identified at -0.45 V. Through operando spectroscopic characterization, the probing results reveal that the overall enhancement of CO production on the MnSA/SNC is possibly caused by the S atom in the local MnN3S1 moiety, as the sulfur atom may induce the formation of S-O bonding to stabilize the critical intermediate, *COOH, for CO2-to-CO. Our results provide novel design insights into the field of SACs for the eCO2RR.
RESUMEN
BACKGROUND: The portosystemic shunt is the pathway between the portal vein (PV) and systemic circulation. A spontaneous intrahepatic portosystemic shunt (SPISS) is a rare portosystemic shunt type. Here we report an extremely rare type of SPISS, a spontaneous intrahepatic PV-inferior vena cava shunt (SPIVCS). CASE SUMMARY: A 66-year-old woman was admitted to our hospital with the complaint of abdominal distention and a decreased appetite for 1 mo. The patient had a 20-year history of hepatitis B surface antigen positivity and a 5-year history of cirrhosis. She had been treated with Chinese herbal medicine for a long time. Liver function tests showed: alanine aminotransferase, 35 U/L; aspartate aminotransferase, 42 U/L; serum albumin (ALB) 32.2 g/L; and serum ascites ALB gradient, 25.2 g/L. Abdominal ultrasonography and enhanced computed tomography showed that the left branch of the PV was thin and occluded; the right branch of the PV was thick and showed a vermicular dilatation vein cluster in the upper pole of the right kidney that branched out and converged into the inferior vena cava from the bare area of the lower right posterior lobe of the liver. We diagnosed her with an extremely rare SPIVCS caused by portal hypertension and provided symptomatic treatment after admission. One week later, her symptoms disappeared and she was discharged. CONCLUSION: SPIVCS is a rare portosystemic shunt with a clear history of cirrhosis and portal hypertension. Clarifying the type PV shunt has important clinical significance.
RESUMEN
ETHNOPHARMACOLOGICAL RELEVANCE: Cynanchum bungei Decne. (CB) (Asclepiadaceae) and its two related species Cynanchum auriculatum Royle ex Wight. (CA) and Cynanchum wilfordii (Maxim.) Hemsl. (CW) are well known Chinese herbal medicines known by the name Baishouwu. Among them, CB has long been used for nourishing the kidney and liver, strengthening the bones and muscles, and regulating stomachache. However, to date, no comprehensive review on Baishouwu has been published. AIM OF THE REVIEW: This review aims to provide a comprehensive summary on traditional uses, phytochemistry, pharmacology, and toxicology of the three herbal components of Baishouwu with the ultimate objective of providing a guide for future scientific and therapeutic potential use of Baishouwu. MATERIAL AND METHODS: A literature search was undertaken on CB, CA and CW by analyzing the information from scientific databases (SciFinder, Pubmed, Elsevier, Google Scholar, Web of Science, and Baidu Scholar). Information was also gathered from local classic herbal literatures and conference papers on ethnopharmacology and the information provided in this review has been obtained from peer-reviewed papers. RESULTS: Comparative analysis of literature search indicate that ethnopharmacological use of CB was recorded in China, however, CA and CW have been used in China, Korea and Japan. To date, 151 chemical compounds have been isolated from these species, and the major chemical constituents have been revealed to be acetophenones, C21-steroids, terpenoids, and alkaloids. These compounds and extracts have been proven to exhibit significant pharmacological activities, including anti-tumor, anti-inflammatory, immunomodulatory, hypolipidemic, anti-obesity, hepatoprotective, antifungal, antiviral, anti-depressant, vasodilating and estrogenic activities. CONCLUSIONS: CB, CA and CW collectively known as Baishouwu are valuable medicinal herbs with multiple pharmacological activities. The traditional use for nourishing liver is closely associated with the hepatoprotective activity. The available literature performs that various of the activity of Baishouwu can be attributed to acetophenones and C21-steroids. It is high time that more efforts should be focused on the underlying mechanisms of their beneficial bioactivities and the structure activity relationship of the constituents, as well as their potential synergistic and antagonistic effects. The proper toxicology evaluation is crucial to guarantee the safety, efficacy, and eligibility for medical use. Further research on the comprehensive evaluation of medicinal quality and the understanding of multi-target network pharmacology of Baishouwu is in great request.