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1.
Angew Chem Int Ed Engl ; : e202410555, 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39251391

RESUMEN

Lattice-oxygen is highly oxidizable, ideal for electrocatalytic C-H oxidation but insufficient alone for C(O)-C bond cleavage due to the non-removable nature of lattice sites. Here, we present a visible light-assisted electrochemical method of in-situ formulating removable lattice-oxygen sites in a nickel-oxyhydroxide (ESE-NiOOH) electrocatalyst. This catalyst efficiently converts aromatic alcohols and carbonyls with C(O)-C fragments from lignin and plastics into benzoic acids (BAs) with high yields (83-99%). Without light irradiation, ESE-NiOOH's intrinsic lattice-oxygen is non-removable and inert for C(O)-C bond cleavage. In-situ characterizations show light-induced lattice-oxygen removal and regeneration via OH- refilling. Theoretical calculations identify the nucleophilic oxygen attack on ketone-derived carbanion as a rate-determining step, which can be remarkably facilitated by removable lattice-oxygen to activate α-C-H bonds. As a proof-of-concept, an "electrochemical funnel" strategy is developed for high-efficiency upgrading aromatic mixtures with C(O)-C moieties into BA with up to 94% yield. This in-situ removal-regeneration approach for lattice sites opens an avenue for the tailored design of interfacial electrocatalysts to selectively upcycle waste carbon sources into valuable products.

2.
Nat Commun ; 15(1): 7800, 2024 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-39242511

RESUMEN

Dynamic tracking of spinal instrumentation could facilitate real-time evaluation of hardware integrity and in so doing alert patients/clinicians of potential failure(s). Critically, no method yet exists to continually monitor the integrity of spinal hardware and by proxy the process of spinal arthrodesis; as such hardware failures are often not appreciated until clinical symptoms manifest. Accordingly, herein, we report on the development and engineering of a bio-adhesive metal detector array (BioMDA), a potential wearable solution for real-time, non-invasive positional analyses of osseous implants within the spine. The electromagnetic coupling mechanism and intimate interfacial adhesion enable the precise sensing of the metallic implants position without the use of radiation. The customized decoupling models developed facilitate the precise determination of the horizontal and vertical positions of the implants with incredible levels of accuracy (e.g., <0.5 mm). These data support the potential use of BioMDA in real-time/dynamic postoperative monitoring of spinal implants.


Asunto(s)
Metales , Prótesis e Implantes , Columna Vertebral , Dispositivos Electrónicos Vestibles , Humanos , Columna Vertebral/cirugía , Metales/química , Adhesivos , Fusión Vertebral/instrumentación , Fusión Vertebral/métodos
3.
Ecol Evol ; 14(9): e70268, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39263460

RESUMEN

Macropsini is a tribe of Eurymelinae in the family Cicadellidae that is widely distributed worldwide. Still, its taxonomic status has been unstable, and the classification of certain clades at the genus level has been controversial. The aim of this study is to address the patterns and processes that explain the structure and the evolution of the mitogenomes of Macropsini, while contributing to the resolution of systematic issues involving five of their genera. To this task, the mitogenomes of 26 species of the tribe were sequenced and characterized, and their phylogenetic relationships were reconstructed. The results revealed that the nucleotide composition of mitochondrial genes in these 26 species was significantly skewed toward A and T. Codons ending with T or A in relative synonymous codon usage were significantly more prevalent than those ending with C or G. The parity plot, neutrality plot, and correspondence analysis revealed that mutation and selective pressure affect codon usage patterns. In the phylogenetic relationships of the Macropsini, the monophyly of Pedionis and Macropsis was well-supported. Meanwhile, Oncopsis revealed paraphyletic regarding Pediopsoides. In conclusion, this research not only contributes the valuable data to the understanding of the mitogenome of the Macropsini but also provides a reference for future investigations on codon usage patterns, potential adaptive evolution, and the phylogeny of the mitogenome within the subfamily Eurymelinae.

4.
Polymers (Basel) ; 16(17)2024 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-39274021

RESUMEN

As the only natural source of aromatic biopolymers, lignin can be converted into value-added chemicals and biofuels, showing great potential in realizing the development of green chemistry. At present, lignin is predominantly used for combustion to generate energy, and the real value of lignin is difficult to maximize. Accordingly, the depolymerization of lignin is of great significance for its high-value utilization. This review discusses the latest progress in the field of lignin depolymerization, including catalytic conversion systems using various thermochemical, chemocatalytic, photocatalytic, electrocatalytic, and biological depolymerization methods, as well as the involved reaction mechanisms and obtained products of various protocols, focusing on green and efficient lignin depolymerization strategies. In addition, the challenges faced by lignin depolymerization are also expounded, putting forward possible directions of developing lignin depolymerization strategies in the future.

5.
Cell Discov ; 10(1): 94, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39251577

RESUMEN

Adult skeletal muscle stem cells, also known satellite cells (SCs), are quiescent and activate in response to injury. However, the activation mechanisms of quiescent SCs (QSCs) remain largely unknown. Here, we investigated the metabolic regulation of SC activation by identifying regulatory metabolites that promote SC activation. Using targeted metabolomics, we found that spermidine acts as a regulatory metabolite to promote SC activation and muscle regeneration in mice. Mechanistically, spermidine activates SCs via generating hypusinated eIF5A. Using SC-specific eIF5A-knockout (KO) and Myod-KO mice, we further found that eIF5A is required for spermidine-mediated SC activation by controlling MyoD translation. More significantly, depletion of eIF5A in SCs results in impaired muscle regeneration in mice. Together, the findings of our study define a novel mechanism that is essential for SC activation and acts via spermidine-eIF5A-mediated MyoD translation. Our findings suggest that the spermidine-eIF5A axis represents a promising pharmacological target in efforts to activate endogenous SCs for the treatment of muscular disease.

7.
J Agric Food Chem ; 72(36): 20101-20113, 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39223077

RESUMEN

The green peach aphid, Myzus persicae, is a worldwide agricultural pest. Chlorpyrifos has been widely used to control M. persicae for decades, thus leading to a high resistance to chlorpyrifos. Recent studies have found that insect odorant binding proteins (OBPs) play essential roles in insecticide resistance. However, the potential resistance mechanism underlying the cross-link between aphid OBPs and chlorpyrifos remains unclear. In this study, two OBPs (MperOBP3 and MperOBP7) were found overexpressed in M. persicae chlorpyrifos-resistant strains (CRR) compared to chlorpyrifos-sensitive strains (CSS); furthermore, chlorpyrifos can significantly induce the expression of both OBPs. An in vitro binding assay indicated that both OBPs strongly bind with chlorpyrifos; an in vivo RNAi and toxicity bioassay confirmed silencing either of the two OBPs can increase the susceptibility of aphids to chlorpyrifos, suggesting that overexpression of MperOBP3 and MperOBP7 contributes to the development of resistance of M. persicae to chlorpyrifos. Our findings provide novel insights into insect OBPs-mediated resistance mechanisms.


Asunto(s)
Áfidos , Cloropirifos , Proteínas de Insectos , Resistencia a los Insecticidas , Insecticidas , Receptores Odorantes , Animales , Áfidos/genética , Áfidos/efectos de los fármacos , Áfidos/metabolismo , Cloropirifos/metabolismo , Cloropirifos/farmacología , Receptores Odorantes/genética , Receptores Odorantes/metabolismo , Receptores Odorantes/química , Resistencia a los Insecticidas/genética , Proteínas de Insectos/genética , Proteínas de Insectos/metabolismo , Proteínas de Insectos/química , Insecticidas/farmacología , Insecticidas/metabolismo , Prunus persica/genética , Prunus persica/parasitología , Prunus persica/metabolismo , Prunus persica/química
8.
J Hazard Mater ; 479: 135762, 2024 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-39255666

RESUMEN

Spread of antibiotic resistance genes (ARGs) in aquatic ecosystems poses a significant global challenge to public health. The potential effects of water temperature perturbation induced by specific water environment changes on ARGs transmission are still unclear. The conjugate transfer of plasmid-mediated ARGs under water temperature perturbation was investigated in this study. The conjugate transfer frequency (CTF) was only 7.16 × 10-7 at a constant water temperature of 5 °C, and it reached 2.18 × 10-5 at 30 °C. Interestingly, compared to the constant 5 °C, the water temperature perturbations (cooling and warming models between 5-30 °C) significantly promoted the CTF. Intracellular reactive oxygen species was a dominant factor, which not only directly affected the CTF of ARGs, but also functioned indirectly via influencing the cell membrane permeability and cell adhesion. Compared to the constant 5 °C, water temperature perturbations significantly elevated the gene expression associated with intercellular contact, cell membrane permeability, oxidative stress responses, and energy driven force for CTF. Furthermore, based on the mathematical model predictions, the stabilization times of acquiring plasmid maintenance were shortened to 184 h and 190 h under cooling and warming model, respectively, thus the water temperature perturbations promoted the ARGs transmission in natural conditions compared with the constant low temperature conditions.

9.
RNA Biol ; 21(1): 29-45, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-39256954

RESUMEN

Adar-mediated adenosine-to-inosine (A-to-I) mRNA editing is a conserved mechanism that exerts diverse regulatory functions during the development, evolution, and adaptation of metazoans. The accurate detection of RNA editing sites helps us understand their biological significance. In this work, with an improved genome assembly of honeybee (Apis mellifera), we used a new orthology-based methodology to complement the traditional pipeline of (de novo) RNA editing detection. Compared to the outcome of traditional pipeline, we retrieved many novel editing sites in CDS that are deeply conserved between honeybee and other distantly related insects. The newly retrieved sites were missed by the traditional de novo identification due to the stringent criteria for controlling false-positive rate. Caste-specific editing sites are identified, including an Ile>Met auto-recoding site in Adar. This recoding was even conserved between honeybee and bumblebee, suggesting its putative regulatory role in shaping the phenotypic plasticity of eusocial Hymenoptera. In summary, we proposed a complementary approach to the traditional pipeline and retrieved several previously unnoticed CDS editing sites. From both technical and biological aspects, our works facilitate future researches on finding the functional editing sites and advance our understanding on the connection between RNA editing and the great phenotypic diversity of organisms.


Asunto(s)
Adenosina , Evolución Molecular , Inosina , Edición de ARN , Animales , Inosina/genética , Inosina/metabolismo , Abejas/genética , Adenosina/metabolismo , Adenosina/genética , Secuencia Conservada , Adenosina Desaminasa/genética , Adenosina Desaminasa/metabolismo
10.
Bioresour Technol ; 410: 131306, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39155020

RESUMEN

Livestock manure harbors antibiotic resistance genes (ARGs), and aerobic composting (AC) is widely adopted for waste management. However, mitigating ARG resurgence in later stages remains challenging. This work aims to curb ARGs rebounding through a Fenton-like reaction during food waste and swine manure co-composting. Results revealed that 0.025 % zerovalent iron (ZVI) + 0.5 % hydrogen peroxide (H2O2) facilitated maximum ARG, mobile genetic elements (MGEs), and 16 s rRNA removal with reductions of 2.68, 2.69, and 1.4 logs. Spectroscopic analysis confirmed Fenton-like reaction and cell apoptosis analysis indicated that 0.025 % ZVI and 0.5 % H2O2 treatment had the maximum early apoptosis, least observed, and normal cells on day 30. Redundancy analysis highlighted the influence of bacterial communities and physicochemical properties on ARGs, with MGEs playing a crucial role in Fenton treatments. Our findings suggest incorporating ZVI and H2O2 in composting can significantly reduce ARGs and enhance waste management practices.


Asunto(s)
Compostaje , Farmacorresistencia Microbiana , Peróxido de Hidrógeno , Hierro , Estiércol , Compostaje/métodos , Farmacorresistencia Microbiana/genética , Animales , Porcinos , Secuencias Repetitivas Esparcidas , ARN Ribosómico 16S/genética , Genes Bacterianos , Antibacterianos/farmacología
11.
Gels ; 10(8)2024 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-39195071

RESUMEN

In order to explore the formation mechanism of the emulsion gel induced by high pressure processing (HPP) and its encapsulation and protection of functional ingredients, a curcumin-loaded whey protein isolate (WPI)/κ-carrageenan (κ-CG) composite emulsion gel induced by HPP was prepared. The effect of pressure (400, 500 and 600 MPa), holding time (10, 20 and 30 min) and concentration of κ-CG (0.8%, 1.0% and 1.2%, w/v) on the swelling rate, gel strength, the stability of curcumin in the emulsion gel, water distribution and its mobility, as well as the contents of interface protein were characterized. The results showed that the addition of κ-CG significantly reduced the protein concentration required for the formation of emulsion gel induced by HPP and greatly reduced the swelling rate of the emulsion gel. The gel strength and storage stability of the composite emulsion gels increased with the increase in pressure (400-600 MPa) and holding time (10-30 min). When the pressure increased to 500 MPa, the stability of curcumin in the emulsion gel significantly improved. When the ratio of WPI to κ-CG was 12:1 (the κ-CG concentration was 1.0%), both the photochemical and thermal stability of curcumin were higher than those of the other two ratios. The HPP significantly increased the mobility of monolayer water in the system, while the mobility of multilayer water and immobilized water was significantly reduced. Increasing the holding time and the concentration of κ-CG both can result in an increase in the interfacial protein content in the oil/water system, and the HPP treatment had a significant effect on the composition of the interfacial protein of the emulsion gel.

12.
Front Endocrinol (Lausanne) ; 15: 1392533, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39114294

RESUMEN

Background: Previous observational studies have reported a possible association between circulating lipids and lipid-lowering drugs and male infertility (MIF), as well as the mediating role of circulating vitamin D. Then, due to issues such as bias, reverse causality, and residual confounding, inferring causal relationships from these studies may be challenging. Therefore, this study aims to explore the effects of circulating lipids and lipid-lowering drugs on MIF through Mendelian randomization (MR) analysis and evaluate the mediating role of vitamin D. Method: Genetic variations related to lipid traits and the lipid-lowering effect of lipid modification targets are extracted from the Global Alliance for Lipid Genetics Genome-Wide Association Study. The summary statistics for MIF are from the FinnGen 9th edition. Using quantitative expression feature loci data from relevant organizations to obtain genetic variations related to gene expression level, further to explore the relationship between these target gene expression levels and MIF risk. Two-step MR analysis is used to explore the mediating role of vitamin D. Multiple sensitivity analysis methods (co-localization analysis, Egger intercept test, Cochrane's Q test, pleiotropy residuals and outliers (MR-PRESSO), and the leave-one-out method) are used to demonstrate the reliability of our results. Result: In our study, we observed that lipid modification of four lipid-lowering drug targets was associated with MIF risk, the LDLR activator (equivalent to a 1-SD decrease in LDL-C) (OR=1.94, 95% CI 1.14-3.28, FDR=0.040), LPL activator (equivalent to a 1-SD decrease in TG) (OR=1.86, 95% CI 1.25-2.76, FDR=0.022), and CETP inhibitor (equivalent to a 1-SD increase in HDL-C) (OR=1.28, 95% CI 1.07-1.53, FDR=0.035) were associated with a higher risk of MIF. The HMGCR inhibitor (equivalent to a 1-SD decrease in LDL-C) was associated with a lower risk of MIF (OR=0.38, 95% CI 0.17-0.83, FDR=0.39). Lipid-modifying effects of three targets were partially mediated by serum vitamin D levels. Mediation was 0.035 (LDLR activator), 0.012 (LPL activator), and 0.030 (CETP inhibitor), with mediation ratios of 5.34% (LDLR activator), 1.94% (LPL activator), and 12.2% (CETP inhibitor), respectively. In addition, there was no evidence that lipid properties and lipid modification effects of six other lipid-lowering drug targets were associated with MIF risk. Multiple sensitivity analysis methods revealed insignificant evidence of bias arising from pleiotropy or genetic confounding. Conclusion: This study did not support lipid traits (LDL-C, HDL-C, TG, Apo-A1, and Apo-B) as pathogenic risk factors for MIF. It emphasized that LPL, LDLR, CETP, and HMGCR were promising drug targets for improving male fertility.


Asunto(s)
Estudio de Asociación del Genoma Completo , Infertilidad Masculina , Análisis de la Aleatorización Mendeliana , Humanos , Masculino , Infertilidad Masculina/genética , Lípidos/sangre , Vitamina D/sangre , Polimorfismo de Nucleótido Simple , Proteínas de Transferencia de Ésteres de Colesterol/genética , Hipolipemiantes/uso terapéutico , Receptores de LDL/genética , Hidroximetilglutaril-CoA Reductasas/genética
13.
Sci Total Environ ; 951: 175443, 2024 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-39134273

RESUMEN

To reveal the outstanding high-emission problems that occur when heavy-duty diesel vehicles (HDDV) pass uphill and downhill, this study proposes a method to depict the nitrogen oxides (NOx) and carbon dioxide (CO2) high-emission driving behaviors caused by slopes from the perspective of engine principles. By calculating emission and grade data of HDDV based on on-board diagnostic (OBD) data and digital elevation model (DEM) data, the 262 short trips including uphill, flat-road and downhill are firstly obtained through the rule-based short trip segmentation method, and the significant correlation between the road grade and emissions of the short trips is verified by Kendall's Tau and K-means clustering. Secondly, by comparing the distribution changes of three speed categories (acceleration state, constant speed state and deceleration state), the differences in HDDV operating states under different grade levels are discussed. Finally, the machine learning models (Random Forest, XGBoost and Elastic Net), are used to develop the NOx and CO2 emission estimation model, identifying high-emission driving behaviors, particularly during uphill driving, which showed the highest proportion of high-emission. Explained by the feature importance and SHapley Additive exPlanations (SHAP) model that large accelerator pedal opening, frequent aggressive acceleration, and high engine load have positive effects both on NOx and CO2 emissions. The difference is in the air-fuel ratio that the engine in the rich or slightly lean burning state will increase CO2 emissions and the lean burning state will increase NOx emissions. In addition, due to the uncertainty of the actual uphill, drivers often undergo a rapid "deceleration-uniform-acceleration" process, which significantly contributes to high NOx and CO2 emissions from the engine perspective. The findings provide insights for designing driving strategies in slope scenarios and offer a novel perspective on depicting driving behaviors.

14.
World J Diabetes ; 15(8): 1692-1703, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-39192861

RESUMEN

Diabetes mellitus (DM) and obesity have become public issues of global concern. Bariatric surgery for the treatment of obesity combined with type 2 DM has been shown to be a safe and effective approach; however, there are limited studies that have systematically addressed the challenges of surgical treatment of obesity combined with DM. In this review, we summarize and answer the most pressing questions in the field of surgical treatment of obesity-associated DM. I believe that our insights will be of great help to clinicians in their daily practice.

15.
bioRxiv ; 2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39149248

RESUMEN

Ovarian clear cell carcinoma (CCC) has an East Asian preponderance. It is associated with endometriosis, a benign condition where endometrial (inner lining of the uterus) tissue is found outside the uterus and on the peritoneal surface, in the abdominal or pelvic space. CCC is relatively more resistant to conventional chemotherapy compared to other ovarian cancer subtypes and is associated with a poorer prognosis. In this study, we recruited and obtained tumour tissues from seven patients across the four stages of CCC. The tumour and the tumour microenvironment (TME) from 7 CCC patients spanning clinical stages 1-4 were transcriptionally profiled using high-resolution scRNA-seq to gain insight into CCC's biological mechanisms. Firstly, we built a scRNA-seq resource for the CCC tumour microenvironment (TME). Secondly, we identified the different cell type proportions and found high levels of immune infiltration in CCC. Thirdly, since CCC is associated with endometriosis, we compared CCC with two publicly available endometriosis scRNA-seq datasets. The CCC malignant cells showed similarities with glandular secretory and ciliated epithelial cells found in endometriosis. Finally, we determined the differences in cell-cell communication between various cell types present in CCC TME and endometriosis conditions to gain insights into the transformations in CCC.

16.
Adv Mater ; : e2404534, 2024 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-39183503

RESUMEN

Large skin wounds, with extensive surface area and deep vertical full-thickness involvement, can pose significant challenges in clinical settings. Traditional routes for repairing skin wounds encompass three hallmarks: 1) scab formation for hemostasis; 2) proliferation and migration of epidermal cells for wound closure; 3) proliferation, migration, and functionalization of fibroblasts and endothelial cells for dermal remodeling. However, this route face remarkable challenges to healing large wounds, usually leading to disordered structures and loss of functions in the regenerated skin, due to limited control on the transition among the three stages. In this work, an implantable bioelectronics is developed that enables the synchronization of the three stages, offering accelerated and high-quality healing of large skin wounds. The system efficiently electro-transfect local cells near the wounds, forcing cellular proliferation, while providing a 3D porous environments for synchronized migration of epidermal and dermal cells. In vivo experiments demonstrated that the system achieved synchronous progression of multiple layers within the wounds, leading to the reconstruction of a complete skin structure similar to healthy skin, which presents a new avenue for the clinical translation of large wound healing.

17.
Ann Intensive Care ; 14(1): 127, 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39162882

RESUMEN

BACKGROUND: A combination of prone positioning (PP) and venovenous extracorporeal membrane oxygenation (VV-ECMO) is safe, feasible, and associated with potentially improved survival for severe acute respiratory distress syndrome (ARDS). However, whether ARDS patients, especially non-COVID-19 patients, placed in PP before VV-ECMO should continue PP after a VV-ECMO connection is unknown. This study aimed to test the hypothesis that early use of PP during VV-ECMO could increase the proportion of patients successfully weaned from ECMO support in severe ARDS patients who received PP before ECMO. METHODS: In this prospective observational study, patients with severe ARDS who were treated with VV-ECMO were divided into two groups: the prone group and the supine group, based on whether early PP was combined with VV-ECMO. The proportion of patients successfully weaned from VV-ECMO and 60-day mortality were analyzed before and after propensity score matching. RESULTS: A total of 165 patients were enrolled, 50 in the prone and 115 in the supine group. Thirty-two (64%) and 61 (53%) patients were successfully weaned from ECMO in the prone and the supine groups, respectively. The proportion of patients successfully weaned from VV-ECMO in the prone group tended to be higher, albeit not statistically significant. During PP, there was a significant increase in partial pressure of arterial oxygen (PaO2) without a change in ventilator or ECMO settings. Tidal impedance shifted significantly to the dorsal region, and lung ultrasound scores significantly decreased in the anterior and posterior regions. Forty-five propensity score-matched patients were included in each group. In this matched sample, the prone group had a higher proportion of patients successfully weaned from VV-ECMO (64.4% vs. 42.2%; P = 0.035) and lower 60-day mortality (37.8% vs. 60.0%; P = 0.035). CONCLUSIONS: Patients with severe ARDS placed in PP before VV-ECMO should continue PP after VV-ECMO support. This approach could increase the probability of successful weaning from VV-ECMO. TRIAL REGISTRATION: ClinicalTrials.Gov: NCT04139733. Registered 23 October 2019.

18.
Angew Chem Int Ed Engl ; : e202414392, 2024 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-39180230

RESUMEN

The thermodynamically and kinetically sluggish electrocatalytic C-N coupling from CO2 and NO3- is inert to initially take place while typically occurring after CO2 protonation, which severely dwindles urea efficiency and carbon atom economy. Herein, we report a single O-philic adsorption strategy to facilitate initial C-N coupling of *OCO and subsequent protonation over dual-metal hetero-single-atoms in N2-Fe-(N-B)2-Cu-N2 coordination mode (FeN4/B2CuN2@NC), which greatly inhibits the formation of C-containing byproducts and facilitates urea electrosynthesis in an unprecedented C-selectivity of 97.1% with urea yield of 2072.5 µg h-1 mgcat.-1 and 71.9% faradaic efficiency, outperforming state-of-the-art electrodes. The carbon-directed antibonding interaction with Cu-B is elaborated to benefit single O-philic adsorption of CO2 rather than conventional C-end or bridging O,O-end adsorption modes, which can accelerate the kinetics of initiated C-N coupling and protonation. Theoretical results indicate that the O- monodentate adsorption pathway benefits the thermodynamics of the C-N coupling of *OCO with *NO2 and the protonation rate-determining step, which markedly inhibits CO2 direct protonation. This oriented strategy of manipulating reactant adsorption patterns to initiate a specific step is universal to moderate oxophilic transition metals and offers a kinetic-enhanced path for multiple conversion processes.

19.
J Cell Sci ; 2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-39155850

RESUMEN

His Domain Protein Tyrosine Phosphatase (HD-PTP) facilitates function of the endosomal sorting complexes required for transport (ESCRTs) during multivesicular body (MVB) formation. To uncover its role in physiological homeostasis, embryonic lethality caused by a complete lack of HD-PTP was bypassed through generation of hypomorphic mice expressing reduced protein, resulting in animals that are viable into adulthood. These mice exhibited marked lipodystrophy and decreased receptor-mediated signaling within white adipose tissue (WAT), involving multiple prominent pathways including RAS/MAPK, PI3K/AKT and RTKs such as EGFR. EGFR signaling was dissected in vitro to assess the nature of defective signaling, revealing decreased trans-autophosphorylation and downstream effector activation, despite normal EGF binding. This corresponds to decreased plasma membrane cholesterol and increased lysosomal cholesterol, likely resulting from defective endosomal maturation necessary for cholesterol trafficking and homeostasis. ESCRT components Vps4 and HRS have previously been implicated in cholesterol homeostasis, thus these findings expand knowledge on which ESCRT subunits are involved in cholesterol homeostasis and highlight a non-canonical role for HD-PTP in signal regulation and adipose tissue homeostasis.

20.
ChemSusChem ; : e202401416, 2024 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-39177006

RESUMEN

The synthesis of biofuel γ-valerolactone (GVL) from accessible biomass is an attractive and challenging goal. Here, we report an efficient, one-pot, and mild strategy for the efficient production of GVL from various biomass saccharides without using any homogeneous acid as a co-catalyst and molecular hydrogen as a hydrogen donor. A versatile porous tin-containing material (Sn(M)-S) was designed as an individual heterogeneous catalyst. As high as 68.4% yield of GVL form glucose was achieved in the presence of ammonia borane as a solid hydrogen donor under mild conditions, with GVL yields of 76.2%, 68.9%, 62.5%, and 52.2% being obtained from fructose, sucrose, cellobiose, and cellulose, respectively. The synergistic effect of Sn and sulfonic acid group in Sn(M)-S not only provides appropriate Lewis acid sites to promote the isomerization of glucose into fructose but also affords abundant Brønsted sites for the following conversion steps. Moreover, Sn(M)-S(1) showed good stability and reusability during consecutive recycles.

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