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Electrocatalytic CO2 reduction reaction (CO2RR) conducted in a flow‐based device exhibits a substantial enhancement in Faradaic efficiency and catalytic current density compared to a conventional H‐type configuration. This highlights the distinct catalytic environment and behavior inherent in flow cells as opposed to H cells. To investigate the authentic properties of a catalyst within a flow‐based device, customized flow cells have been specifically devised for operando techniques during CO2RR and CORR, rather than resorting to an in‐situ three‐electrode H‐type configuration with its disparate catalytic environment and performance. This approach ensures a catalytic environment identical to that employed in electrochemical measurements. This review delineates the disparities between H‐type and flow‐based cells as well as the operando techniques tailored for flow‐based devices, including X‐ray absorption spectroscopy and Raman spectroscopy, preserving a consistent catalytic environment. It also compiles recent findings on copper‐based systems using operando flow‐based devices. The operando insights reveal a significant augmentation in catalytic current density, impacting both chemical properties and crystal structures. Furthermore, the observation of various catalytic intermediates enriches our comprehension. In essence, the application of operando techniques to flow‐based devices furnishes a comprehensive understanding of the catalytic behavior exhibited by diverse systems, propelling progress toward achieving Net Zero emissions. [ABSTRACT FROM AUTHOR]

Developing ruthenium‐based heterogeneous catalysts with an efficient and stable interface is essential for enhanced acidic oxygen evolution reaction (OER). Herein, we report a defect‐rich ultrathin boron nitride nanosheet support with relatively independent electron donor and acceptor sites, which serves as an electron reservoir and receiving station for RuO2, realizing the rapid supply and reception of electrons. Through precisely controlling the reaction interface, a low OER overpotential of only 180 mV (at 10 mA cm−2) and long‐term operational stability (350 h) are achieved, suggesting potential practical applications. In situ characterization and theoretical calculations have validated the existence of a localized electronic recycling between RuO2 and ultrathin BN nanosheets (BNNS). The electron‐rich Ru sites accelerate the adsorption of water molecules and the dissociation of intermediates, while the interconnection between the O‐terminal and B‐terminal edge establishes electronic back‐donation, effectively suppressing the over‐oxidation of lattice oxygen. This study provides a new perspective for constructing a stable and highly active catalytic interface. [ABSTRACT FROM AUTHOR]

Breast cancer is now the most frequently diagnosed malignancy, and metastasis remains the leading cause of death in breast cancer. However, little is known about the dynamic changes during the evolvement of dissemination. In this study, 65 968 cells from four patients with breast cancer and paired metastatic axillary lymph nodes are profiled using single‐cell RNA sequencing (scRNA‐seq) and spatial transcriptomics. A disseminated cancer cell cluster with high levels of oxidative phosphorylation (OXPHOS), including the upregulation of cytochrome C oxidase subunit 6C and dehydrogenase/reductase 2, is identified. The transition between glycolysis and OXPHOS when dissemination initiates is noticed. Furthermore, this distinct cell cluster is distributed along the tumor's leading edge. The findings here are verified in three different cohorts of breast cancer patients and an external scRNA‐seq dataset, which includes eight patients with breast cancer and paired metastatic axillary lymph nodes. This work describes the dynamic metabolic evolvement of early disseminated breast cancer and reveals a switch between glycolysis and OXPHOS in breast cancer cells as the early event during lymph node metastasis. [ABSTRACT FROM AUTHOR]

Objective Target-controlled infusion (TCI) of propofol is an effective way of delivering propofol during endoscopy. However, the ideal effect-site concentration ( Ce) of propofol has not yet been defined in an Asian population. This study aimed to determine the ideal Ce of propofol in painless gastrointestinal endoscopy in a Taiwanese population. Methods A total of 121 consecutive patients undergoing diagnostic endoscopy were recruited for this study. The endoscopic procedure was carried out within 1 h. TCI of propofol was utilized during the procedure. All patients received the same regimen to induce conscious sedation, including a bolus of midazolam (0.04 mg/kg) and fentanyl (0.5 μg/kg). The Ce of propofol was calculated using the Schneider model. Patients were randomly assigned to either the low Ce group (1.5-2.5 μg/mL) or high Ce group (3.0-4.0 μg/m L). Their cardiovascular and respiratory events were monitored during the procedure and the patients' post-procedure satisfaction was evaluated. Results The mean requirement for propofol was 232.02 mg in the low Ce group and 329.56 mg in the high Ce group, respectively ( P < 0.0001). No unexpected event was observed in either group. However, more episodes of hypotension were observed in the high Ce group ( P = 0.026). The post-procedure satisfaction rate between the two groups was comparable. Conclusion A low Ce of propofol TCI (1.5-2.5 μg/m L) achieved adequate anesthesia, reduced the risk of hypotension, and attained a high satisfaction rate in a Taiwanese population undergoing diagnostic painless endoscopy. [ABSTRACT FROM AUTHOR]

Abstract: The role of glutamate 398 in the autocatalytic processing of Bacillus licheniformis γ-glutamyltranspeptidase (BlGGT) was explored by site-directed mutagenesis. This glutamate was substituted by either alanine, aspartate, arginine or glutamine and the expressed mutant enzymes were purified to apparent homogeneity with metal-affinity chromatography. SDS–PAGE analysis showed that E398A, E398D and E398K were unable to process themselves into a large and a small subunit. However, E398Q was not only able to process itself, but also had a catalytic activity comparable to that of BlGGT. As compared with the wild-type enzyme, no significant change in circular dichroism spectra was observed for the mutant proteins. Thermal unfolding of BlGGT, E398A, E398D, E398K and E398Q followed the two-state unfolding process with a transition point (T m) of 47.7–69.4 °C. Tryptophan fluorescence spectra of the mutant enzymes were different from the wild-type protein in terms of fluorescence intensity. Native BlGGT started to unfold beyond ∼1.92 M guanidine hydrochloride (GdnHCl) and reached an unfolded intermediate, [GdnHCl]0.5, N–U, at 3.07 M equivalent to free energy change () of 14.53 kcal/mol for the N → U process, whereas the denaturation midpoints for the mutant enzymes were 1.31–2.99 M equivalent to of 3.29–12.05 kcal/mol. Taken together, these results strongly suggest that the explored glutamate residue is indeed important for the autocatalytic processing of BlGGT. [Copyright &y& Elsevier]