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1.
Chem Rev ; 2024 Sep 11.
Article in English | MEDLINE | ID: mdl-39259040

ABSTRACT

Gas bubbles generated by the hydrogen evolution reaction and oxygen evolution reaction during water electrolysis influence the energy conversion efficiency of hydrogen production. Here, we survey what is known about the interaction of gas bubbles and electrode surfaces and the influence of gas evolution on practicable devices used for water electrolysis. We outline the physical processes occurring during the life cycle of a bubble, summarize techniques used to characterize gas evolution phenomena in situ and in practical device environments, and discuss ways that electrodes can be tailored to facilitate gas removal at high current densities. Lastly, we review efforts to model the behavior of individual gas bubbles and multiphase flows produced at gas-evolving electrodes. We conclude our review with a short summary of outstanding questions that could be answered by future efforts to characterize gas evolution in electrochemical device environments or by improved simulations of multiphase flows.

2.
Int J Mol Sci ; 25(17)2024 Sep 02.
Article in English | MEDLINE | ID: mdl-39273495

ABSTRACT

Plants encounter numerous adversities during growth, necessitating the identification of common stress activators to bolster their resistance. However, the current understanding of these activators' mechanisms remains limited. This study identified three anti-stress activators applicable to apple trees, all of which elevate plant proline content to enhance resistance against various adversities. The results showed that the application of these sugar substitutes increased apple proline content by two to three times compared to the untreated group. Even at a lower concentration, these activators triggered plant stress resistance without compromising apple fruit quality. Therefore, these three sugar substitutes can be exogenously sprayed on apple trees to augment proline content and fortify stress resistance. Given their effectiveness and low production cost, these activators possess significant application value. Since they have been widely used in the food industry, they hold potential for broader application in plants, fostering apple industry development.


Subject(s)
Malus , Proline , Stress, Physiological , Sugars , Malus/metabolism , Malus/physiology , Proline/metabolism , Sugars/metabolism , Fruit/metabolism , Gene Expression Regulation, Plant
3.
Int J Mol Sci ; 25(16)2024 Aug 15.
Article in English | MEDLINE | ID: mdl-39201563

ABSTRACT

Nitric oxide (NO) has been firmly established as a key signaling molecule in plants, playing a significant role in regulating growth, development and stress responses. Given the imperative of sustainable agriculture and the urgent need to meet the escalating global demand for food, it is imperative to safeguard crop plants from the effects of climate fluctuations. Plants respond to environmental challenges by producing redox molecules, including reactive oxygen species (ROS) and reactive nitrogen species (RNS), which regulate cellular, physiological, and molecular processes. Nitric oxide (NO) plays a crucial role in plant stress tolerance, acting as a signaling molecule or free radical. NO is involved in various developmental processes in plants through diverse mechanisms. Exogenous NO supplementation can alleviate the toxicity of abiotic stresses and enhance plant resistance. In this review we summarize the studies regarding the production of NO in peroxisomes, and how its molecule and its derived products, (ONOO-) and S-nitrosoglutathione (GSNO) affect ROS metabolism in peroxisomes. Peroxisomal antioxidant enzymes including catalase (CAT), are key targets of NO-mediated post-translational modification (PTM) highlighting the dynamic metabolism of ROS and RNS in peroxisomes.


Subject(s)
Nitric Oxide , Peroxisomes , Protein Processing, Post-Translational , Reactive Nitrogen Species , Reactive Oxygen Species , Peroxisomes/metabolism , Reactive Oxygen Species/metabolism , Nitric Oxide/metabolism , Reactive Nitrogen Species/metabolism , Plants/metabolism
4.
Angew Chem Int Ed Engl ; 63(37): e202403186, 2024 Sep 09.
Article in English | MEDLINE | ID: mdl-38900647

ABSTRACT

Here, we report CdS quantum dot (QD) gels, a three-dimensional network of interconnected CdS QDs, as a new type of direct hydrogen atom transfer (d-HAT) photocatalyst for C-H activation. We discovered that the photoexcited CdS QD gel could generate various neutral radicals, including α-amido, heterocyclic, acyl, and benzylic radicals, from their corresponding stable molecular substrates, including amides, thio/ethers, aldehydes, and benzylic compounds. Its C-H activation ability imparts a broad substrate and reaction scope. The mechanistic study reveals that this reactivity is intrinsic to CdS materials, and the neutral radical generation did not proceed via the conventional sequential electron transfer and proton transfer pathway. Instead, the C-H bonds are activated by the photoexcited CdS QD gel via a d-HAT mechanism. This d-HAT mechanism is supported by the linear correlation between the logarithm of the C-H bond activation rate constant and the C-H bond dissociation energy (BDE) with a Brønsted slope α=0.5. Our findings expand the currently limited direct hydrogen atom transfer photocatalysis toolbox and provide new possibilities for photocatalytic C-H activation.

6.
Environ Technol ; : 1-13, 2024 May 21.
Article in English | MEDLINE | ID: mdl-38773903

ABSTRACT

The increasing concentrations of heavy metals in livestock wastewater pose a serious threat to the environmental safety and human health, limiting its resource utilisation. In the present study, microalgae and nanoscale zero-valent iron were selected to construct a coupled system for copper-containing wastewater treatment. The addition of 50 mg·L-1 nanoscale zero-valent iron (50 nm) was the optimal value for the experiment, which could significantly increase the biomass of microalgae. In addition, nanoscale zero-valent iron stimulated microalgal secretion of extracellular polymeric substances, increasing the contents of binding sites, organic ligands, and functional groups on the microalgal surfaces and ultimately promoting the settling of microalgae and binding of heavy metals. The coupled system could quickly adapt to copper-containing wastewater of 10 mg·L-1, and the copper removal rate reached 94.99%. Adsorption and uptake by organisms, together with the contribution of zero-valent iron nanoparticles, are the major copper removal pathways. Overall, this work offers a novel technical solution for enhanced treatment of copper-containing livestock wastewater, which will help improve the efficiency and quality of wastewater treatment.

7.
J Org Chem ; 89(9): 6389-6394, 2024 May 03.
Article in English | MEDLINE | ID: mdl-38607957

ABSTRACT

This report benchmarks a tris(amino)cyclopropenium (TAC) salt as an electron-transfer mediator for anodic oxidation reactions in comparison to two known mediators: a triarylamine and a triarylimidazole derivative. The three mediators have redox potentials, diffusion coefficients, and heterogeneous electron transfer rates similar to those of glassy carbon electrodes in acetonitrile/KPF6. However, they differ significantly in their performance in two electro-organic reactions: anodic fluorination of a dithiane and anodic oxidation of 4-methoxybenzyl alcohol. These differences are rationalized based on variable stability in the presence of reaction components (e.g., NEt3·3HF, lutidine, and Cs2CO3) as well as very different rates of electron transfer with the organic substrate. Overall, this work highlights the advantages and disadvantages of each mediator and provides a foundation for expanding the applications of TACs in electro-organic synthesis moving forward.

8.
Analyst ; 149(11): 3108-3114, 2024 May 28.
Article in English | MEDLINE | ID: mdl-38639050

ABSTRACT

Here, we report a proof-of-concept resistive pulse method for analyzing chiral amino acids utilizing metal-amino acid crystallization differences. This method involves introducing an amino acid sample solution into a micropipette through a pressure-driven flow. The sample then mixes with a metal ion solution inside the pipette, forming metal-amino acid crystals. The crystal size depends on the enantiomeric excess (x) of chiral amino acid samples. Large x values lead to large crystals. The crystal size difference is then reflected in the resistive pulse size as they block the ionic transport in a micropipette to different extents. We used Cd-cystine crystallization as a model system and found approximately five times the mean current pulse size difference for racemic (x = 0) and L-only (x = +1) cystine samples. A similar result was observed for aspartate. Our discovery opens up new opportunities for micro/nanoscopic chiral amino acid analysis, which can potentially be used in single-cell analysis.


Subject(s)
Amino Acids , Crystallization , Stereoisomerism , Amino Acids/chemistry , Cystine/chemistry , Cadmium/chemistry , Aspartic Acid/chemistry , Metals/chemistry
9.
Nat Commun ; 15(1): 2061, 2024 Mar 07.
Article in English | MEDLINE | ID: mdl-38448433

ABSTRACT

Plants are capable of altering root growth direction to curtail exposure to a saline environment (termed halotropism). The root cap that surrounds root tip meristematic stem cells plays crucial roles in perceiving and responding to environmental stimuli. However, how the root cap mediates root halotropism remains undetermined. Here, we identified a root cap-localized NAC transcription factor, SOMBRERO (SMB), that is required for root halotropism. Its effect on root halotropism is attributable to the establishment of asymmetric auxin distribution in the lateral root cap (LRC) rather than to the alteration of cellular sodium equilibrium or amyloplast statoliths. Furthermore, SMB is essential for basal expression of the auxin influx carrier gene AUX1 in LRC and for auxin redistribution in a spatiotemporally-regulated manner, thereby leading to directional bending of roots away from higher salinity. Our findings uncover an SMB-AUX1-auxin module linking the role of the root cap to the activation of root halotropism.


Subject(s)
Arabidopsis , Transcription Factors , Transcription Factors/genetics , Arabidopsis/genetics , Gene Expression Regulation , Salt Stress/genetics , Indoleacetic Acids
10.
Article in English | MEDLINE | ID: mdl-38450312

ABSTRACT

This review summarizes the recent advancements in alternating current (AC)-driven electroorganic synthesis since 2021 and discusses the reactivities AC electrolysis provides to achieve new and unique organic transformations.

11.
Arch Gynecol Obstet ; 309(5): 2167-2173, 2024 May.
Article in English | MEDLINE | ID: mdl-38503849

ABSTRACT

OBJECTIVE: The purpose of this study is to compare the clinical efficacy of oral dydrogesterone and micronized vaginal progesterone (MVP) gel during the first HRT-FET cycle. METHODS: A retrospective cohort study based on a total of 344 women undergoing their first HRT-FET cycles without Gonadotropin-Releasing Hormone agonist (GnRH-a) pretreatment was conducted. All the cycles were allocated to two groups in the reproductive medical center at the University of Hong Kong-Shenzhen Hospital. One group (n = 193) received oral dydrogesterone 30 mg/d before embryo transfer, while the other group (n = 151) received MVP gel 180 mg/d. RESULTS: The demographics and baseline characteristics of two groups were comparable. We found no statistically significant difference in live birth rate (24.35% vs. 31.13%, P = 0.16), clinical pregnancy rate (34.72% vs. 36.42%, P = 0.74), embryo implantation rate (25.09% vs. 28.36%, P = 0.43), positive pregnancy rate (42.49% vs 38.41%, P = 0.45), miscarriage rate (9.33% vs 3.97%, P = 0.05), or ectopic pregnancy rate (0.52% vs. 0.66%, P = 0.86) between the oral dydrogesterone group and MVP gel group. In the multivariate logistic regression analysis for covariates, medication used for luteal support was not associated with live birth rate (OR = 0.73, 95% CI: 0.32-1.57, P = 0.45). And the different luteal support medication did not have a significant positive association with the live birth rate in the cycles with day 2 embryo transferred (OR = 1.39, 95% CI:0.66-2.39, P = 0.39) and blastocyst transferred (OR = 1.31 95% CI:0.64-2.69, P = 0.46). CONCLUSION: 30 mg/d oral dydrogesterone and 180 mg/d MVP gel revealed similar reproductive outcomes in HRT-FET cycles in the study.


Subject(s)
Dydrogesterone , Progesterone , Pregnancy , Female , Humans , Progesterone/therapeutic use , Retrospective Studies , Pregnancy Rate , Embryo Transfer , Lutein
12.
J Am Chem Soc ; 146(7): 4489-4499, 2024 Feb 21.
Article in English | MEDLINE | ID: mdl-38327095

ABSTRACT

Two-dimensional covalent organic frameworks (COFs) are an emerging class of photocatalytic materials for solar energy conversion. In this work, we report a pair of structurally isomeric COFs with reversed imine bond directions, which leads to drastic differences in their physical properties, photophysical behaviors, and photocatalytic CO2 reduction performance after incorporating a Re(bpy)(CO)3Cl molecular catalyst through bipyridyl units on the COF backbone (Re-COF). Using the combination of ultrafast spectroscopy and theory, we attributed these differences to the polarized nature of the imine bond that imparts a preferential direction to intramolecular charge transfer (ICT) upon photoexcitation, where the bipyridyl unit acts as an electron acceptor in the forward imine case (f-COF) and as an electron donor in the reverse imine case (r-COF). These interactions ultimately lead the Re-f-COF isomer to function as an efficient CO2 reduction photocatalyst, while the Re-r-COF isomer shows minimal photocatalytic activity. These findings not only reveal the essential role linker chemistry plays in COF photophysical and photocatalytic properties but also offer a unique opportunity to design photosensitizers that can selectively direct charges.

13.
Phytochem Anal ; 35(2): 336-349, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37787024

ABSTRACT

INTRODUCTION: The root of Bupleurum scorzonerifolium Willd. (BS) is officially recognized in the Chinese Pharmacopoeia. In contrast, the aerial part of BS (ABS), accounting for 80% of BS, is typically discarded, causing potential waste of medicinal resources. ABS has shown benefits in the treatment of inflammation-related diseases in China and Spain, and the material basis underlying its anti-inflammatory effects must be systematically elucidated for the rational use of ABS. OBJECTIVE: We aimed to screen and validate the anti-inflammatory quality markers (Q-markers) of ABS and to confirm the ideal time for ABS harvesting. METHODS: The chemical components and anti-inflammatory effects of ABS from 10 extracted parts were analyzed by UPLC-Q-TOF-MS/MS and in a lipopolysaccharide (LPS)-induced cell model. Anti-inflammatory substances were screened by Pearson bivariate analysis and gray correlation analysis, and the anti-inflammatory effects were verified in a zebrafish tail-cutting inflammation model. HPLC was applied to measure the Q-marker contents of ABS in different harvesting periods. RESULTS: Ten ABS extracts effectively alleviated the increase in LPS-induced proinflammatory cytokines in RAW 264.7 cells. Forty components were identified from them, among which 27 were common components. Eight components were correlated with anti-inflammatory effects, which were confirmed to reverse the expression of proinflammatory and anti-inflammatory factors in a zebrafish model. Chlorogenic acid, hypericin, rutin, quercetin, and isorhamnetin can be detected by HPLC, and the maximum contents of these five Q-markers were obtained in the sample harvested in August. CONCLUSION: The anti-inflammatory Q-markers of ABS were elucidated by chromatographic-pharmacodynamic-stoichiometric analysis, which served as a crucial basis for ABS quality control.


Subject(s)
Bupleurum , Tandem Mass Spectrometry , Mice , Animals , Zebrafish , Chromatography, High Pressure Liquid , Bupleurum/chemistry , RAW 264.7 Cells , Lipopolysaccharides/pharmacology , Anti-Inflammatory Agents/pharmacology , Anti-Inflammatory Agents/analysis , Inflammation/drug therapy , Plant Components, Aerial/chemistry
14.
Adv Mater ; 36(13): e2303869, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37632843

ABSTRACT

High-performance perovskite solar cells (PSCs) typically require interfacial passivation, yet this is challenging for the buried interface, owing to the dissolution of passivation agents during the deposition of perovskites. Here, this limitation is overcome with in situ buried-interface passivation-achieved via directly adding a cyanoacrylic-acid-based molecular additive, namely BT-T, into the perovskite precursor solution. Classical and ab initio molecular dynamics simulations reveal that BT-T spontaneously may self-assemble at the buried interface during the formation of the perovskite layer on a nickel oxide hole-transporting layer. The preferential buried-interface passivation results in facilitated hole transfer and suppressed charge recombination. In addition, residual BT-T molecules in the perovskite layer enhance its stability and homogeneity. A power-conversion efficiency (PCE) of 23.48% for 1.0 cm2 inverted-structure PSCs is reported. The encapsulated PSC retains 95.4% of its initial PCE following 1960 h maximum-power-point tracking under continuous light illumination at 65 °C (i.e., ISOS-L-2I protocol). The demonstration of operating-stable PSCs under accelerated ageing conditions represents a step closer to the commercialization of this emerging technology.

17.
Front Neurol ; 14: 1240526, 2023.
Article in English | MEDLINE | ID: mdl-37780713

ABSTRACT

Eperisone hydrochloride is a central muscle relaxant used to treat osteoporosis. Seizures are rare side effects of eperisone hydrochloride and have been previously reported in the medical literature in overdose situations but not at regular doses. This case report describes a 42-year-old male painter who developed severe bilateral tonic seizures after the initiation of eperisone hydrochloride at regular doses for low back pain. Symptoms gradually eased in the days following the discontinuation of eperisone hydrochloride and antiepileptic treatment, with no recurrence. This rare adverse drug reaction warrants clinical awareness; however, the mechanisms underlying these adverse reactions remain to be clarified.

18.
J Am Chem Soc ; 145(40): 21851-21859, 2023 Oct 11.
Article in English | MEDLINE | ID: mdl-37747918

ABSTRACT

The functional group compatibility of an electrosynthetic method is typically limited by its potential reaction window. Here, we report that alternating current (AC) electrolysis can overcome such potential window-limited functional group compatibility. Using alkene heterodifunctionalization as a model system, we design and demonstrate a series of AC-driven reactions that add two functional groups sequentially and separately under the cathodic and anodic pulses, including chloro- and bromotrilfuoromethylation as well as chlorosulfonylation. We discovered that the oscillating redox environment during AC electrolysis allows the regeneration of the redox-active functional groups after their oxidation or reduction in the preceding step. As a result, even though redox labile functional groups such as pyrrole, quinone, and aryl thioether fall in the reaction potential window, they are tolerated under AC electrolysis conditions, leading to synthetically useful yields. The cyclic voltammetric study has confirmed that the product yield is limited by the extent of starting material regeneration during the redox cycling. Our findings open a new avenue for improving functional group compatibility in electrosynthesis and show the possibility of predicting the product yield under AC electrolysis from voltammogram features.

19.
Chin Med ; 18(1): 98, 2023 Aug 11.
Article in English | MEDLINE | ID: mdl-37568235

ABSTRACT

BACKGROUND: Ulcerative colitis (UC) is an inflammatory disease of the colon that is characterized by mucosal ulcers. Given its increasing prevalence worldwide, it is imperative to develop safe and effective drugs for treating UC. Emodin, a natural anthraquinone derivative present in various medicinal herbs, has demonstrated therapeutic effects against UC. However, low bioavailability due to poor water solubility limits its clinical applications. METHODS: Emodin-borate nanoparticles (EmB) were synthesized to improve drug solubility, and they modified with oligomeric mannitol into microgels (EmB-MO) for targeted delivery to intestinal macrophages that express mannose receptors. UC was induced in a mouse model using dextran sulfate sodium (DSS), and different drug formulations were administered to the mice via drinking water. The levels of inflammation-related factors in the colon tissues and fecal matter were measured using enzyme-linked immunosorbent assay. Intestinal permeability was evaluated using fluorescein isothiocyanate dextran. HE staining, in vivo imaging, real-time PCR, and western blotting were performed to assess intestinal barrier dysfunction. RESULTS: Both EmB and EmB-MO markedly alleviated the symptoms of UC, including body weight loss, stool inconsistency, and bloody stools and restored the levels of pro- and anti-inflammatory cytokines. However, the therapeutic effects of EmB-MO on the macroscopic and immunological indices were stronger than those of EmB and similar to those of 5-aminosalicylic acid. Furthermore, EmB-MO selectively accumulated in the inflamed colon epithelium and restored the levels of the gut barrier proteins such as ZO-1 and Occludin. CONCLUSIONS: EmB-MO encapsulation significantly improved water solubility, which translated to greater therapeutic effects on the immune balance and gut barrier function in mice with DSS-induced UC. Our findings provide novel insights into developing emodin-derived drugs for the management of UC.

20.
Nat Plants ; 9(9): 1514-1529, 2023 09.
Article in English | MEDLINE | ID: mdl-37604972

ABSTRACT

Ammonium toxicity affecting plant metabolism and development is a worldwide problem impeding crop production. Remarkably, rice (Oryza sativa L.) favours ammonium as its major nitrogen source in paddy fields. We set up a forward-genetic screen to decipher the molecular mechanisms conferring rice ammonium tolerance and identified rohan showing root hypersensitivity to ammonium due to a missense mutation in an argininosuccinate lyase (ASL)-encoding gene. ASL localizes to plastids and its expression is induced by ammonium. ASL alleviates ammonium-inhibited root elongation by converting the excessive glutamine to arginine. Consequently, arginine leads to auxin accumulation in the root meristem, thereby stimulating root elongation under high ammonium. Furthermore, we identified natural variation in the ASL allele between japonica and indica subspecies explaining their different root sensitivity towards ammonium. Finally, we show that ASL expression positively correlates with root ammonium tolerance and that nitrogen use efficiency and yield can be improved through a gain-of-function approach.


Subject(s)
Oryza , Oryza/genetics , Alleles , Arginine , Nitrogen , Plastids/genetics
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