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1.
Chem Rev ; 123(16): 9915-9939, 2023 08 23.
Artículo en Inglés | MEDLINE | ID: mdl-37470246

RESUMEN

Environmental concerns over waste plastics' effect on the environment are leading to the creation of biodegradable plastics. Biodegradable plastics may serve as a promising approach to manage the issue of environmental accumulation of plastic waste in the ocean and soil. Biodegradable plastics are the type of polymers that can be degraded by microorganisms into small molecules (e.g., H2O, CO2, and CH4). However, there are misconceptions surrounding biodegradable plastics. For example, the term "biodegradable" on product labeling can be misconstrued by the public to imply that the product will degrade under any environmental conditions. Such misleading information leads to consumer encouragement of excessive consumption of certain goods and increased littering of products labeled as "biodegradable". This review not only provides a comprehensive overview of the state-of-the-art biodegradable plastics but also clarifies the definitions and various terms associated with biodegradable plastics, including oxo-degradable plastics, enzyme-mediated plastics, and biodegradation agents. Analytical techniques and standard test methods to evaluate the biodegradability of polymeric materials in alignment with international standards are summarized. The review summarizes the properties and industrial applications of previously developed biodegradable plastics and then discusses how biomass-derived monomers can create new types of biodegradable polymers by utilizing their unique chemical properties from oxygen-containing functional groups. The terminology and methodologies covered in the paper provide a perspective on directions for the design of new biodegradable polymers that possess not only advanced performance for practical applications but also environmental benefits.


Asunto(s)
Plásticos Biodegradables , Plásticos Biodegradables/química , Polímeros/química , Biodegradación Ambiental , Biomasa
2.
Nat Mater ; 22(1): 100-108, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36266572

RESUMEN

Iridium-based electrocatalysts remain the only practical anode catalysts for proton exchange membrane (PEM) water electrolysis, due to their excellent stability under acidic oxygen evolution reaction (OER), but are greatly limited by their high cost and low reserves. Here, we report a nickel-stabilized, ruthenium dioxide (Ni-RuO2) catalyst, a promising alternative to iridium, with high activity and durability in acidic OER for PEM water electrolysis. While pristine RuO2 showed poor acidic OER stability and degraded within a short period of continuous operation, the incorporation of Ni greatly stabilized the RuO2 lattice and extended its durability by more than one order of magnitude. When applied to the anode of a PEM water electrolyser, our Ni-RuO2 catalyst demonstrated >1,000 h stability under a water-splitting current of 200 mA cm-2, suggesting potential for practical applications. Density functional theory studies, coupled with operando differential electrochemical mass spectroscopy analysis, confirmed the adsorbate-evolving mechanism on Ni-RuO2, as well as the critical role of Ni dopants in stabilization of surface Ru and subsurface oxygen for improved OER durability.

3.
Opt Lett ; 49(10): 2625-2628, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38748121

RESUMEN

We present an encoding scheme of a single logical qubit with single-sided quantum dot (QD)-cavity systems, which is immune to the collective decoherence. By adjusting the Purcell factor to satisfy the balanced reflection condition, the detrimental effects of unbalanced reflection between the coupled and uncoupled QD-cavity systems can be effectively suppressed. Furthermore, the fidelity of each step can be increased to unity regardless of the strong coupling regime and the weak coupling regime of cavity quantum electrodynamics (QED) with the assistance of waveform correctors. The scheme requires QD-cavity systems and simple linear optical elements, which can be implemented with the currently experimental techniques.

4.
Chemphyschem ; : e202400413, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38747673

RESUMEN

In order to explore the unique physiological roles of gas signaling molecules and gasotransmitters in vivo, chemists have engineered a variety of gas-responsive polymers that can monitor their changes in cellular milieu, and gas-releasing polymers that can orchestrate the release of gases. These have advanced their potential applications in the field of bio-imaging, nanodelivery, and theranostics. Since these polymers are of different chain structures and properties, the morphology of their assemblies will manifest distinct transitions after responding to gas or releasing gas. In this review, we summarize the fundamental design rationale of gas-responsive and gas-releasing polymers in structure and their controlled transition in self-assembled morphology and function, as well as present some perspectives in this prosperous field. Emerging challenges faced for the future research are also discussed.

5.
Nanotechnology ; 35(36)2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38865974

RESUMEN

Significant efforts have been dedicated to designing porous organic cage compounds with geometric complexity and topological diversity. However, the use of these cage molecules as premade building units for constructing infinite cage-based superstructures remains unexplored. Here, we report the use of a panel-decorated phosphine organic cage as a special monomer to achieve supramolecular polymerization, resulting in cage-by-cage noncovalent polymers through the synergy of metal-coordination and intercageπ-πdimerization. At a monomer concentration of 122 mM, the average degree of polymerization reaches 17, corresponding to a molecular weight of 26 kDa. The obtained cage-based supramolecular polymers can further hierarchically self-assemble into vesicular morphologies or one-dimensional nanofiber architectures. Selective control over the cosolvents can regulate their structural hierarchy and assembled morphology. This approach paves a new way for the construction of cage-based hierarchical assemblies and materials.

6.
Kidney Blood Press Res ; 49(1): 430-442, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38797171

RESUMEN

BACKGROUND: N-glycosylation is one of the most common posttranslational modifications in humans, and these alterations are associated with kidney diseases. METHODS: A novel technological approach, single-cell N-acetyllactosamine sequencing (scLacNAc-seq), was applied to simultaneously detect N-glycosylation expression and the transcriptome at single-cell resolution in three human kidney tissues from zero-time biopsy. Cell clusters, glycation abundance in each cell cluster, functional enrichment analysis, cell-cell crosstalk, and pseudotime analysis were applied. RESULTS: Using scLacNAc-seq, 24,247 cells and 22 cell clusters were identified, and N-glycan abundance in each cell was obtained. Transcriptome analysis revealed a close connection between capillary endothelial cells (CapECs) and parietal epithelial cells (PECs). PECs and CapECs communicate with each other through several pairs of ligand receptors (e.g., TGFB1-EGFR, GRN-EGFR, TIMP1-FGFR2, VEGFB-FLT1, ANGPT2-TEK, and GRN-TNFRSF1A). Finally, a regulatory network of cell-cell crosstalk between PECs and CapECs was constructed, which is involved in cell development. CONCLUSIONS: We here, for the first time, constructed the glycosylation profile of 22 cell clusters in the human kidney from zero-time biopsy. Moreover, cell-cell communication between PECs and CapECs through the ligand-receptor system may play a crucial regulatory role in cell proliferation.


Asunto(s)
Comunicación Celular , Células Endoteliales , Células Epiteliales , Riñón , Humanos , Glicosilación , Células Endoteliales/metabolismo , Células Epiteliales/metabolismo , Riñón/metabolismo , Riñón/citología , Análisis de la Célula Individual
7.
BMC Anesthesiol ; 24(1): 12, 2024 01 03.
Artículo en Inglés | MEDLINE | ID: mdl-38172695

RESUMEN

BACKGROUND: The alteration of the prognostic nutritional index (PNI) or the utilization of distinct anesthesia strategies has been linked to the prognosis of various cancer types, but the existing evidence is limited and inconclusive, particularly for colorectal cancer (CRC). Our objective was to evaluate the association between PNI change and progression free survival (PFS) and overall survival (OS) in patients treated with CRC surgery after propofol-based or sevoflurane-based anesthesia. METHODS: We conducted a retrospective analysis of 414 patients with CRC who underwent surgical resection. Among them, 165 patients received propofol-based total intravenous anesthesia (TIVA-P), while 249 patients received sevoflurane-based inhalation anesthesia (IA-S). The PNI change (ΔPNI) was calculated by subtracting the pre-surgery PNI from the post-surgery PNI, and patients were categorized into high (≥ -2.25) and low (< -2.25) ΔPNI groups. Univariate and multivariate analyses were employed to evaluate the effects of the two anesthesia methods, ΔPNI, and their potential interaction on PFS and OS. RESULTS: The median duration of follow-up was 35.9 months (interquartile range: 18-60 months). The five-year OS rates were 63.0% in the TIVA-P group and 59.8% in the IA-S group (hazard ratio [HR]: 0.96; 95% confidence interval [CI]: 0.70-1.35; p = 0.864), while the five-year PFS rates were 55.8% and 51.0% (HR: 0.92; 95% CI: 0.68-1.26; p = 0.614), respectively. In comparison to patients in the low ΔPNI group, those in the high ΔPNI group exhibited a favorable association with both OS (HR: 0.57; 95% CI: 0.40-0.76; p < 0.001) and PFS (HR: 0.58; 95% CI: 0.43-0.79; p < 0.001). Stratified analysis based on ΔPNI revealed significant protective effects in the propofol-treated participants within the high ΔPNI group, whereas such effects were not observed in the low ΔPNI group, for both OS (p for interaction = 0.004) and PFS (p for interaction = 0.024). CONCLUSIONS: Our data revealed that among patients who underwent CRC surgery, those treated with TIVA-P exhibited superior survival outcomes compared to those who received IA-S, particularly among individuals with a high degree of PNI change.


Asunto(s)
Neoplasias Colorrectales , Propofol , Humanos , Pronóstico , Sevoflurano , Evaluación Nutricional , Estudios Retrospectivos , Resultado del Tratamiento , Anestesia por Inhalación/métodos , Neoplasias Colorrectales/cirugía
8.
Biotechnol Lett ; 46(3): 373-383, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38493279

RESUMEN

OBJECTIVE: Currently, there is lack of a consistent and highly enriched source for docosapentaenoic acid (n-3 DPA, C22:5), and this work report the isolation of microorganism that naturally produces n-3 DPA. RESULTS: In this work, we screened microorganisms in our culture collections with the goal to isolate a strain with high levels of n-3 DPA. We isolated a strain of Sphaeroforma arctica that produces up to 11% n-3 DPA in total fatty acid and has a high n-3 DPA to DHA/EPA ratio. The cell growth of the isolated strain was characterized using microscopy imaging and flow cytometer technologies to confirm the coenocytic pattern of cell divisions previously described in S. arctica. Our novel isolate of S. arctica grew more robustly and produced significantly more n-3 DPA compared to previously isolated and described strains indicating the uniqueness of the discovered strain. CONCLUSION: Overall, this work reports a first isolate n-3 DPA producing microorganism and establishes the foundation for future strain improvement and elucidation of the physiological function of this LC-PUFA for human nutrition and health.


Asunto(s)
Ácidos Grasos Insaturados , Ácidos Grasos Insaturados/metabolismo , Estramenopilos/metabolismo , Estramenopilos/aislamiento & purificación
9.
Altern Ther Health Med ; 30(4): 113-117, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38330561

RESUMEN

Objective: To examine the therapeutic effects of vitamin E combined with recombinant human epidermal growth factor on recurrent oral ulcers as well as on the levels of serum superoxide dismutase (SOD), interleukin-10 (IL-10), and tumor necrosis factor- (TNF-α), to provide evidence to facilitate medical management. Method: From June 2021 to May 2022, 84 patients with recurrent oral ulcers assessed and treated in our hospital were assigned to the control group and observation group with 42 cases in each group. Vitamin E was administered to the control group, while recombinant human epidermal growth factor and vitamin E were administered to the observation group. The clinical efficacy, serum SOD level, inflammatory factor level (IL-10, TNF-α), immune function index, clinical symptom improvement, pain disappearance time, healing time of ulcer surface, and adverse reactions were examined. Results: Clinical efficacy of the observation group (92.86%) was considerably greater than the control group (73.81%), (P < .05). Following treatment, the observation group had comparatively higher levels of serum SOD and significantly decreased TNF-α and IL-10 concentrations compared to the control group (P < .05). Similarly, post-treatment, the observation group had substantially higher CD3+, CD4+, and CD4+/CD8+ concentrations and lower CD8+ concentrations compared to the normal control (P < .05). In contrast to the control group, the observation group's pain degree score, ulcer diameter, duration for pain relief, and ulcer surface healing time duration were reduced substantially (P < .05). Notably, the incidence of adverse reactions was fairly similar in both groups (P > .05). Conclusion: Vitamin E combined with recombinant human epidermal growth factor has a significant clinical effect on recurrent oral ulcers, can achieve rapid improvement of symptoms in patients, and is relatively safe to be used as a clinical therapy.


Asunto(s)
Factor de Crecimiento Epidérmico , Interleucina-10 , Úlceras Bucales , Superóxido Dismutasa , Factor de Necrosis Tumoral alfa , Vitamina E , Humanos , Interleucina-10/sangre , Femenino , Masculino , Vitamina E/uso terapéutico , Vitamina E/farmacología , Factor de Necrosis Tumoral alfa/sangre , Superóxido Dismutasa/sangre , Superóxido Dismutasa/uso terapéutico , Persona de Mediana Edad , Úlceras Bucales/tratamiento farmacológico , Adulto , Factor de Crecimiento Epidérmico/uso terapéutico , Factor de Crecimiento Epidérmico/sangre , Proteínas Recombinantes/uso terapéutico , Proteínas Recombinantes/administración & dosificación , Anciano , Quimioterapia Combinada , Recurrencia
10.
J Environ Manage ; 350: 119652, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38016235

RESUMEN

Renewable energy (RE) plays a crucial role in global energy transformation, and a thorough study of the potential impact of RE on regional carbon emissions is of great significance. This is particularly relevant to China, which needs to clarify its path to carbon reduction. Using the sample data of 30 provinces in China from 2000 to 2021, this paper uses the Granger causality test to verify the causal relationship between carbon emission intensity (CEI) and other factors. It builds a mediation effect model on this basis to explore the direct impact effect and indirect transmission path of renewable energy utilization (REU) on CEI. The results show that REU has a one-way causal relationship with CEI. REU can directly and indirectly reduce CEI by improving social wealth and changing the direction of energy investment. In addition, REU indirectly increases CEI through the transmission paths of investment in the energy industry - social affluence and industrial level-social affluence. The CEI is indirectly reduced through the conduction paths of (social affluence-Urbanization rate), (Investment in the energy industry-Urbanization rate), (Industrial level-Urbanization rate), and (Industrial level-Investment in the energy industry). These conclusions will assist policymakers in exploring targeted pathways for low-carbon power development, providing a reference for strategic and sustainable carbon reduction policies.


Asunto(s)
Dióxido de Carbono , Carbono , Carbono/análisis , Dióxido de Carbono/análisis , Urbanización , Energía Renovable , China , Desarrollo Económico
11.
Molecules ; 29(4)2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38398519

RESUMEN

To enhance the bioavailability and antihypertensive effect of the anti-depressant drug citalopram hydrobromide (CTH) we developed a sustained-release transdermal delivery system containing CTH. A transdermal diffusion meter was first used to determine the optimal formulation of the CTH transdermal drug delivery system (TDDS). Then, based on the determined formulation, a sustained-release patch was prepared; its physical characteristics, including quality, stickiness, and appearance, were evaluated, and its pharmacokinetics and irritation to the skin were evaluated by applying it to rabbits and rats. The optimal formulation of the CTH TDDS was 49.2% hydroxypropyl methyl cellulose K100M, 32.8% polyvinylpyrrolidone K30, 16% oleic acid-azone, and 2% polyacrylic acid resin II. The system continuously released an effective dose of CTH for 24 h and significantly enhanced its bioavailability, with a higher area under the curve, good stability, and no skin irritation. The developed CTH TDDS possessed a sustained-release effect and good characteristics and pharmacokinetics; therefore, it has the potential for clinical application as an antidepressant.


Asunto(s)
Citalopram , Absorción Cutánea , Ratas , Conejos , Animales , Citalopram/farmacología , Citalopram/metabolismo , Preparaciones de Acción Retardada/farmacología , Administración Cutánea , Piel , Sistemas de Liberación de Medicamentos , Parche Transdérmico
12.
Metab Eng ; 76: 18-28, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36626963

RESUMEN

Plants produce many high-value oleochemical molecules. While oil-crop agriculture is performed at industrial scales, suitable land is not available to meet global oleochemical demand. Worse, establishing new oil-crop farms often comes with the environmental cost of tropical deforestation. The field of metabolic engineering offers tools to transplant oleochemical metabolism into tractable hosts while simultaneously providing access to molecules produced by non-agricultural plants. Here, we evaluate strategies for rewiring metabolism in the oleaginous yeast Yarrowia lipolytica to synthesize a foreign lipid, 3-acetyl-1,2-diacyl-sn-glycerol (acTAG). Oils made up of acTAG have a reduced viscosity and melting point relative to traditional triacylglycerol oils making them attractive as low-grade diesels, lubricants, and emulsifiers. This manuscript describes a metabolic engineering study that established acTAG production at g/L scale, exploration of the impact of lipid bodies on acTAG titer, and a techno-economic analysis that establishes the performance benchmarks required for microbial acTAG production to be economically feasible.


Asunto(s)
Yarrowia , Triglicéridos/metabolismo , Yarrowia/genética , Yarrowia/metabolismo , Ingeniería Metabólica , Metabolismo de los Lípidos , Aceites/metabolismo
13.
Inorg Chem ; 62(13): 5262-5269, 2023 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-36947415

RESUMEN

Porous carbon-supported atomically ordered intermetallic compounds (IMCs) are promising electrocatalysts in boosting oxygen reduction reaction (ORR) for fuel cell applications. However, the formation mechanism of IMC structures under high temperatures is poorly understood, which hampers the synthesis of highly ordered IMC catalysts with promoted ORR performance. Here, we employ high-temperature X-ray diffraction and energy-dispersive spectroscopic elemental mapping techniques to study the formation process of IMCs, by taking PtCo for example, in an industry-relevant impregnation synthesis. We find that high-temperature annealing is crucial in promoting the formation of alloy particles with a stoichiometric Co/Pt ratio, which in turn is the precondition for transforming the disordered alloys to ordered intermetallic structures at a relatively low temperature. Based on the findings, we accordingly synthesize highly ordered L10-type PtCo catalysts with a remarkable ORR performance in fuel cells.

14.
Org Biomol Chem ; 21(7): 1450-1456, 2023 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-36651476

RESUMEN

The Ru(dppbsa)-catalyzed reductive amination of ketones with nitroarenes and nitriles using H2 as the environmentally benign hydrogen surrogate is developed in this study. Cross-experiments demonstrated that both reactions are initiated by the reduction of nitroarenes or nitriles to the corresponding amines, followed by condensation with ketones to give imines and thereafter hydrogenation. However, the route to the formation of an amino-ligated Ru complex during the reduction of nitroarenes or nitriles, followed by in situ nucleophilic C-N coupling, cannot be completely excluded. This newly developed versatile method features good functional group tolerance, which provides a novel design platform for homogeneous catalysts in constructing motifs of secondary amines.

15.
Nanotechnology ; 34(23)2023 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-36848663

RESUMEN

Developing new membranes with both high selectivity and permeability is critical in membrane science since conventional membranes are often limited by the trade-off between selectivity and permeability. In recent years, the emergence of advanced materials with accurate structures at atomic or molecular scale, such as metal organic framework, covalent organic framework, graphene, has accelerated the development of membranes, which benefits the precision of membrane structures. In this review, current state-of-the-art membranes are first reviewed and classified into three different types according to the structures of their building blocks, including laminar structured membranes, framework structured membranes and channel structured membranes, followed by the performance and applications for representative separations (liquid separation and gas separation) of these precisely designed membranes. Last, the challenges and opportunities of these advanced membranes are also discussed.

16.
BMC Surg ; 23(1): 226, 2023 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-37559030

RESUMEN

BACKGROUND: There are few widely accepted and operationally feasible models for predicting the mortality risk of patients in surgical intensive care unit (SICU). Although serum anion gap (AG) is known to be correlated with severe metabolic acidosis, no investigations have been reported about the association between AG level and the outcome during hospitalization in SICU. This study aimed to explore the predictive power of AG for 90-day all-cause mortality in SICU. METHODS: Data of the eligible patients in SICU from 2008 to 2019 was obtained from the Medical Information Mart for Intensive Care IV version 2.0 (MIMIC-IV v2.0) database. Baseline clinical data of the selected patients was compared in different groups stratified by the outcome during their admission via univariate analysis. Restricted cubic spline (RCS) was drawn to confirm the relationship of AG and the short-term mortality. Kaplan-Meier survival curve was plotted in different AG level groups. Univariate and multivariate Cox analyses were performed, and Cox proportional-hazards models were built to investigate an independent role of AG to predict 90-day all-cause mortality risk in SICU. Receiver operating characteristics (ROC) curves analysis was performed to evaluate the predictive value of AG on the 90-day prognosis of patients. RESULTS: A total of 6,395 patients were enrolled in this study and the 90-day all-cause mortality rate was 18.17%. Univariate analysis showed that elevated serum AG was associated with higher mortality (P < 0.001). RCS analysis indicated a positively linear relationship between serum AG and the risk of 90-day all-cause mortality in SICU (χ2 = 4.730, P = 0.193). Kaplan-Meier survival analysis demonstrated that low-AG group (with a cutoff value of 14.10 mmol/L) had a significantly higher cumulative survival rate than the counterpart of high-AG group (χ2 = 96.370, P < 0.001). Cox proportional-hazards models were constructed and confirmed the independent predictive role of AG in 90-day all-cause mortality risk in SICU after adjusting for 23 confounding factors gradually (HR 1.423, 1.246-1.625, P < 0.001). In the further subgroup analyses, a significant interaction was confirmed between AG and sepsis as well as surgery on the risk for the 90-day mortality. The ROC curve showed that the optimal cut-off value of AG for predicting 90-day mortality was 14.89 with sensitivity of 60.7% and specificity of 54.8%. The area under curve (AUC) was 0.602. When combined with SOFA score, the AUC of AG for predicting 90-day prognosis was 0.710, with a sensitivity and specificity of 70% and 62.5% respectively. CONCLUSIONS: Elevated AG (≥ 14.10 mmol/L) is an independent risk factor for predicting severe conditions and poor prognosis of critical ill surgical patients.


Asunto(s)
Equilibrio Ácido-Base , Enfermedad Crítica , Humanos , Estudios Retrospectivos , Sensibilidad y Especificidad , Curva ROC , Pronóstico , Unidades de Cuidados Intensivos
17.
Int J Mol Sci ; 24(2)2023 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-36675117

RESUMEN

YUCCA, belonging to the class B flavin-dependent monooxygenases, catalyzes the rate-limiting step for endogenous auxin synthesis and is implicated in plant-growth regulation and stress response. Systematic analysis of the YUCCA gene family and its stress response benefits the dissection of regulation mechanisms and breeding applications. In this study, 12 YUCCA genes were identified from the mungbean (Vigna radiata L.) genome and were named based on their similarity to AtYUCCAs. Phylogenetic analysis revealed that the 12 VrYUCCAs could be divided into 4 subfamilies. The evidence from enzymatic assays in vitro and transgenetic Arabidopsis in vivo indicated that all the isolated VrYUCCAs had biological activity in response to IAA synthesis. Expression pattern analysis showed that functional redundancy and divergence existed in the VrYUCCA gene family. Four VrYUCCAs were expressed in most tissues, and five VrYUCCAs were specifically highly expressed in the floral organs. The response toward five stresses, namely, auxin (indole-3-acetic acid, IAA), salinity, drought, high temperatures, and cold, was also investigated here. Five VrYUCCAs responded to IAA in the root, while only VrYUCCA8a was induced in the leaf. VrYUCCA2a, VrYUCCA6a, VrYUCCA8a, VrYUCCA8b, and VrYUCCA10 seemed to dominate under abiotic stresses, due to their sensitivity to the other four treatments. However, the response modes of the VrYUCCAs varied, indicating that they may regulate different stresses in distinct ways to finely adjust IAA content. The comprehensive analysis of the VrYUCCAs in this study lays a solid foundation for further investigation of VrYUCCA genes' mechanisms and applications in breeding.


Asunto(s)
Arabidopsis , Vigna , Yucca , Vigna/genética , Vigna/metabolismo , Yucca/metabolismo , Filogenia , Fitomejoramiento , Ácidos Indolacéticos/metabolismo , Arabidopsis/genética , Estrés Fisiológico/genética , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
18.
Angew Chem Int Ed Engl ; 62(14): e202217001, 2023 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-36738302

RESUMEN

Here we present a "breathing" nanogel that is fueled by CO2 gas to perform temporally programmable catalytic polymerization. The nanogel is composed of common frustrated Lewis pair polymers (FLPs). Dynamic CO2 -FLP gas-bridging bonds endow the nanogel with a transient volume contraction, and the resulting proximal effect of bound FLPs unlocks its catalytic capacity toward CO2 . Reverse gas depletion via a CO2 -participated polymerization can induce a reverse nanogel expansion, which shuts down the catalytic activity. Control of external factors (fuel level, temperature or additives) can regulate the breathing period, amplitude and lifecycle, so as to affect the catalytic polymerization. Moreover, editing the nanogel breathing procedure can sequentially evoke the copolymerization of CO2 with different epoxide monomers preloaded therein, which allows to obtain block-tunable copolycarbonates that are unachievable by other methods. This synthetic dissipative system would be function as a prototype of gas-driven nanosynthesizer.

19.
Angew Chem Int Ed Engl ; 62(28): e202305290, 2023 07 10.
Artículo en Inglés | MEDLINE | ID: mdl-37189000

RESUMEN

Fabricating nanoscale assemblies that can respond to gas signaling molecules has emerged as a field of growing interest owing to their unique biomedical applications in gas-guided delivery and gas therapeutics. Yet, among a variety of endogenous gaseous biosignals, exploiting sulfur dioxide (SO2 ) as a cue for controllable self-assembly remains elusive, despite its crucial two-sided roles both in physiology and pathology. Here we show a SO2 -responsive polymersome system assembled from a novel class of cyanine-containing block copolymers. By intake of SO2 gas, the tautomerism of cyanine drives such vesicles to continuously deform, and change into long nanotubes through axial stretching and anisotropic extrusion of the membranes. Unexpectedly, during this order-to-order phase transition, their membranes manifest well SO2 -dose-dependent permselectivity, which allows the cargos of different sizes loaded therein to be selectively transferred across the bilayers. This study would inspire us to better understand and mimic the function of gas signaling molecules in shifting biomembrane shape and managing transmembrane traffic.


Asunto(s)
Polímeros , Dióxido de Azufre
20.
Angew Chem Int Ed Engl ; 62(24): e202302819, 2023 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-36972030

RESUMEN

In supported metal catalysts, the supports would strongly interact with the metal components instead of just acting as a carrier, which greatly affects both of their synthesis and catalytic activity, selectivity, and stability. Carbon is considered as very important but inert support and thus hard to induce strong metal-support interaction (SMSI). This mini-review highlights that sulfur-a documented poison reagent for metal catalysts-when doped in a carbon supports can induce diverse SMSI phenomenon, including electronic metal-support interaction (EMSI), classic SMSI, and reactive metal-support interaction (RMSI). These SMSI between metal and sulfur-doped carbon (S-C) supports enables the catalysts with extraordinary resistance to sintering at high temperatures of up to 1100 °C, which allows the general synthesis of single-atom, alloy cluster, and intermetallic compound catalysts with high dispersion and metal loading for a variety of applications.

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