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1.
Microb Cell Fact ; 23(1): 141, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38760782

RESUMO

BACKGROUND: The oleaginous yeast Rhodotorula toruloides is a promising chassis organism for the biomanufacturing of value-added bioproducts. It can accumulate lipids at a high fraction of biomass. However, metabolic engineering efforts in this organism have progressed at a slower pace than those in more extensively studied yeasts. Few studies have investigated the lipid accumulation phenotype exhibited by R. toruloides under nitrogen limitation conditions. Consequently, there have been only a few studies exploiting the lipid metabolism for higher product titers. RESULTS: We performed a multi-omic investigation of the lipid accumulation phenotype under nitrogen limitation. Specifically, we performed comparative transcriptomic and lipidomic analysis of the oleaginous yeast under nitrogen-sufficient and nitrogen deficient conditions. Clustering analysis of transcriptomic data was used to identify the growth phase where nitrogen-deficient cultures diverged from the baseline conditions. Independently, lipidomic data was used to identify that lipid fractions shifted from mostly phospholipids to mostly storage lipids under the nitrogen-deficient phenotype. Through an integrative lens of transcriptomic and lipidomic analysis, we discovered that R. toruloides undergoes lipid remodeling during nitrogen limitation, wherein the pool of phospholipids gets remodeled to mostly storage lipids. We identify specific mRNAs and pathways that are strongly correlated with an increase in lipid levels, thus identifying putative targets for engineering greater lipid accumulation in R. toruloides. One surprising pathway identified was related to inositol phosphate metabolism, suggesting further inquiry into its role in lipid accumulation. CONCLUSIONS: Integrative analysis identified the specific biosynthetic pathways that are differentially regulated during lipid remodeling. This insight into the mechanisms of lipid accumulation can lead to the success of future metabolic engineering strategies for overproduction of oleochemicals.


Assuntos
Metabolismo dos Lipídeos , Nitrogênio , Rhodotorula , Rhodotorula/metabolismo , Rhodotorula/genética , Nitrogênio/metabolismo , Transcriptoma , Engenharia Metabólica/métodos , Fosfolipídeos/metabolismo , Lipidômica , Lipídeos/biossíntese
2.
Nat Commun ; 15(1): 3823, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38714643

RESUMO

The CRISPR-Cas12a system is more advantageous than the widely used CRISPR-Cas9 system in terms of specificity and multiplexibility. However, its on-target editing efficiency is typically much lower than that of the CRISPR-Cas9 system. Here we improved its on-target editing efficiency by simply incorporating 2-aminoadenine (base Z, which alters canonical Watson-Crick base pairing) into the crRNA to increase the binding affinity between crRNA and its complementary DNA target. The resulting CRISPR-Cas12a (named zCRISPR-Cas12a thereafter) shows an on-target editing efficiency comparable to that of the CRISPR-Cas9 system but with much lower off-target effects than the CRISPR-Cas9 system in mammalian cells. In addition, zCRISPR-Cas12a can be used for precise gene knock-in and highly efficient multiplex genome editing. Overall, the zCRISPR-Cas12a system is superior to the CRISPR-Cas9 system, and our simple crRNA engineering strategy may be extended to other CRISPR-Cas family members as well as their derivatives.


Assuntos
Sistemas CRISPR-Cas , Edição de Genes , Edição de Genes/métodos , Humanos , Células HEK293 , RNA Guia de Sistemas CRISPR-Cas/genética , RNA Guia de Sistemas CRISPR-Cas/metabolismo , RNA/genética , RNA/metabolismo , Proteínas Associadas a CRISPR/metabolismo , Proteínas Associadas a CRISPR/genética , Proteínas de Bactérias , Endodesoxirribonucleases
3.
BMC Oral Health ; 24(1): 594, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38778380

RESUMO

BACKGROUND: Oral frailty has become a worldwide problem among older adults. Although researchers have conducted various studies on oral frailty, its definition remains controversial. PURPOSE: To clarify the concept of oral frailty. METHODS: Online databases PubMed, Web of Science, CINAHL, Cochrane Library, ProQuest, China National Knowledge Infrastructure (CNKI), China Science and Technology Journal Database (VIP), and Wanfang database were searched from inception to September 20, 2023. The reference lists of relevant studies were searched manually. Eligible articles, theses, and books were analyzed using Walker & Avant's concept analysis model. RESULTS: The attributes of oral frailty were abnormal oral structure and/or decline in multi-faceted oral function and coexisting decline in physical, cognitive and social functions. Its antecedents were aging, social frailty, and severe periodontitis, whereas its consequences were decline in physical health and mental health, social withdrawal, lower quality of life and systemic frailty. CONCLUSION: Oral frailty could result in worse conditions among older adults physically, psychologically and socially. Tools based on the concept analysis need to be developed to comprehensively assess oral frailty.


Assuntos
Fragilidade , Saúde Bucal , Humanos , Fragilidade/complicações , Idoso , Qualidade de Vida , Idoso Fragilizado , Envelhecimento/psicologia , Envelhecimento/fisiologia
4.
Plants (Basel) ; 13(9)2024 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-38732430

RESUMO

Salt stress is one of the major abiotic stresses that damage the structure and composition of cell walls. Alginate oligosaccharides (AOS) have been advocated to significantly improve plant stress tolerance. The metabolic mechanism by which AOS induces salt tolerance in rice cell walls remains unclear. Here, we report the impact of AOS foliar application on the cell wall composition of rice seedlings using the salt-tolerant rice variety FL478 and the salt-sensitive variety IR29. Data revealed that salt stress decreased biomass, stem basal width, stem breaking strength, and lodging resistance; however, it increased cell wall thickness. In leaves, exogenous AOS up-regulated the expression level of OSCESA8, increased abscisic acid (ABA) and brassinosteroids (BR) content, and increased ß-galacturonic activity, polygalacturonase activity, xylanase activity, laccase activity, biomass, and cellulose content. Moreover, AOS down-regulated the expression levels of OSMYB46 and OSIRX10 and decreased cell wall hemicellulose, pectin, and lignin content to maintain cell wall stability under salt stress. In stems, AOS increased phenylalamine ammonia-lyase and tyrosine ammonia-lyase activities, while decreasing cellulase, laccase, and ß-glucanase activities. Furthermore, AOS improved the biomass and stem basal width and also enhanced the cellulose, pectin, and lignin content of the stem, As a result, increased resistance to stem breakage strength and alleviated salt stress-induced damage, thus enhancing the lodging resistance. Under salt stress, AOS regulates phytohormones and modifies cellulose, hemicellulose, lignin, and pectin metabolism to maintain cell wall structure and improve stem resistance to lodging. This study aims to alleviate salt stress damage to rice cell walls, enhance resistance to lodging, and improve salt tolerance in rice by exogenous application of AOS.

5.
Sci Total Environ ; 927: 172168, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38582120

RESUMO

Many cities face unprecedented high temperatures with increasing extreme events. Heatwaves pose significant health risks, including cardiovascular diseases, heatstroke, and dehydration. Mapping urban near-surface air temperature (Tair) is crucial for understanding thermal exposure and addressing climate change. Previous studies relied on satellite-derived land surface temperature (LST) and stationary monitoring, but high spaio-temporal Tair mapping is still a challenge. This study optimized a mobile sensing scheme using an electric bicycle platform with environmental and image sensors, and deep learning captured local-scale urban factors. A spatio-temporal data fusion model that consisted of three parts, temporal trend extraction, locality analysis, and neighborhood effect analysis, generated hyperlocal Tair maps. The Results from Beijing demonstrated the effectiveness of the framework, achieving the lowest MAE of 0.02 °C. Optimized data collection and the new model achieved accurate temperature predictions and thermal exposure assessment. Efficiency enhanced sensing strategy was also proposed. The study highlights local-scale factors and spatio-temporal dependencies in addressing heatwaves and climate change impacts in urban areas.

6.
Anal Chem ; 96(15): 6037-6044, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38560885

RESUMO

Dopamine (DA), an essential neurotransmitter, is closely associated with various neurological disorders, whose real-time dynamic monitoring is significant for evaluating the physiological activities of neurons. Electrochemical sensing methods are commonly used to determine DA, but they mostly rely on the redox reaction of its o-phenolic hydroxyl group, which makes it difficult to distinguish it from substances with this group. Here, we design a biomimetic nanozyme inspired by the coordination structure of the copper-based active site of dopamine ß-hydroxylase, which was successfully synthesized via a urea-mediated MOF pyrolysis reconstruction strategy. Experimental studies and theoretical calculations revealed that the nanozyme with Cu-N3 coordination could hydroxylate the carbon atom of the DA ß-site at a suitable potential and that the active sites of this Cu-N3 structure have the lowest binding energy for the DA ß-site. With this property, the new oxidation peak achieves the specific detection of DA rather than the traditional electrochemical signal of o-phenol hydroxyl redox, which would effectively differentiate it from neurotransmitters, such as norepinephrine and epinephrine. The sensor exhibited good monitoring capability in DA concentrations from 0.05 to 16.7 µM, and its limit of detection was 0.03 µM. Finally, the sensor enables the monitoring of DA released from living cells and can be used to quantitatively analyze the effect of polystyrene microplastics on the amount of DA released. The research provides a method for highly specific monitoring of DA and technical support for initial screening for neurocytotoxicity of pollutants.


Assuntos
Dopamina , Oxigenases de Função Mista , Dopamina/química , Fenol , Biomimética , Cobre , Plásticos , Pirólise , Eletrodos , Neurotransmissores , Técnicas Eletroquímicas/métodos
7.
J Am Chem Soc ; 146(15): 10716-10722, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38579164

RESUMO

Chiral alkyl amines are common structural motifs in pharmaceuticals, natural products, synthetic intermediates, and bioactive molecules. An attractive method to prepare these molecules is the asymmetric radical hydroamination; however, this approach has not been explored with dialkyl amine-derived nitrogen-centered radicals since designing a catalytic system to generate the aminium radical cation, to suppress deleterious side reactions such as α-deprotonation and H atom abstraction, and to facilitate enantioselective hydrogen atom transfer is a formidable task. Herein, we describe the application of photoenzymatic catalysis to generate and harness the aminium radical cation for asymmetric intermolecular hydroamination. In this reaction, the flavin-dependent ene-reductase photocatalytically generates the aminium radical cation from the corresponding hydroxylamine and catalyzes the asymmetric intermolecular hydroamination to furnish the enantioenriched tertiary amine, whereby enantioinduction occurs through enzyme-mediated hydrogen atom transfer. This work highlights the use of photoenzymatic catalysis to generate and control highly reactive radical intermediates for asymmetric synthesis, addressing a long-standing challenge in chemical synthesis.

8.
Chembiochem ; : e202400212, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38648232

RESUMO

The ß-hemolytic factor streptolysin S (SLS) is an important linear azol(in)e-containing peptide (LAP) that contributes significantly to the virulence of Streptococcus pyogenes. Despite its discovery 85 years ago, SLS has evaded structural characterizing owing to its notoriously problematic physicochemical properties. Here, we report the discovery and characterization of a structurally analogous hemolytic peptide from Enterococcus caccae, termed enterolysin S (ELS). Through heterologous expression, site-directed mutagenesis, chemoselective modification, and high-resolution mass spectrometry, we found that ELS contains an intriguing contiguous octathiazole moiety. The discovery of ELS expands our knowledge of hemolytic LAPs by adding a new member to this virulence-promoting family of modified peptides.

9.
Bioresour Technol ; 399: 130641, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38552861

RESUMO

This study presents a cost-effective strategy for producing organic acids from glucose and xylose using the acid-tolerant yeast, Issatchenkia orientalis. I. orientalis was engineered to produce lactic acid from xylose, and the resulting strain, SD108XL, successfully converted sorghum hydrolysates into lactic acid. In order to enable low-pH fermentation, a self-buffering strategy, where the lactic acid generated by the SD108XL strain during fermentation served as a buffer, was developed. As a result, the SD108 strain produced 67 g/L of lactic acid from 73 g/L of glucose and 40 g/L of xylose, simulating a sugar composition of sorghum biomass hydrolysates. Moreover, techno-economic analysis underscored the efficiency of the self-buffering strategy in streamlining the downstream process, thereby reducing production costs. These results demonstrate the potential of I. orientalis as a platform strain for the cost-effective production of organic acids from cellulosic hydrolysates.


Assuntos
Ácido Láctico , Pichia , Xilose , Glucose , Análise Custo-Benefício , Fermentação , Saccharomyces cerevisiae
10.
Nat Chem ; 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38528101

RESUMO

Recent efforts in genome mining of ribosomally synthesized and post-translationally modified peptides (RiPPs) have expanded the diversity of post-translational modification chemistries. However, RiPPs are rarely reported as hybrid molecules incorporating biosynthetic machinery from other natural product families. Here we report lipoavitides, a class of RiPP/fatty-acid hybrid lipopeptides that display a unique, putatively membrane-targeting 4-hydroxy-2,4-dimethylpentanoyl (HMP)-modified N terminus. The HMP is formed via condensation of isobutyryl-coenzyme A (isobutyryl-CoA) and methylmalonyl-CoA catalysed by a 3-ketoacyl-(acyl carrier protein) synthase III enzyme, followed by successive tailoring reactions in the fatty acid biosynthetic pathway. The HMP and RiPP substructures are then connected by an acyltransferase exhibiting promiscuous activity towards the fatty acyl and RiPP substrates. Overall, the discovery of lipoavitides contributes a prototype of RiPP/fatty-acid hybrids and provides possible enzymatic tools for lipopeptide bioengineering.

11.
Nat Chem Biol ; 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38448734

RESUMO

Metabolic efficiency profoundly influences organismal fitness. Nonphotosynthetic organisms, from yeast to mammals, derive usable energy primarily through glycolysis and respiration. Although respiration is more energy efficient, some cells favor glycolysis even when oxygen is available (aerobic glycolysis, Warburg effect). A leading explanation is that glycolysis is more efficient in terms of ATP production per unit mass of protein (that is, faster). Through quantitative flux analysis and proteomics, we find, however, that mitochondrial respiration is actually more proteome efficient than aerobic glycolysis. This is shown across yeast strains, T cells, cancer cells, and tissues and tumors in vivo. Instead of aerobic glycolysis being valuable for fast ATP production, it correlates with high glycolytic protein expression, which promotes hypoxic growth. Aerobic glycolytic yeasts do not excel at aerobic growth but outgrow respiratory cells during oxygen limitation. We accordingly propose that aerobic glycolysis emerges from cells maintaining a proteome conducive to both aerobic and hypoxic growth.

12.
PeerJ ; 12: e17068, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38495756

RESUMO

The aim of this experiment was to investigate the effects of exogenous sprays of 5-aminolevulinic acid (5-ALA) and 2-Diethylaminoethyl hexanoate (DTA-6) on the growth and salt tolerance of rice (Oryza sativa L.) seedlings. This study was conducted in a solar greenhouse at Guangdong Ocean University, where 'Huanghuazhan' was selected as the test material, and 40 mg/L 5-ALA and 30 mg/L DTA-6 were applied as foliar sprays at the three-leaf-one-heart stage of rice, followed by treatment with 0.3% NaCl (W/W) 24 h later. A total of six treatments were set up as follows: (1) CK: control, (2) A: 40 mg⋅ L-1 5-ALA, (3) D: 30 mg⋅ L-1 DTA-6, (4) S: 0.3% NaCl, (5) AS: 40 mg⋅ L-1 5-ALA + 0.3% NaCl, and (6) DS: 30 mg⋅ L-1 DTA-6+0.3% NaCl. Samples were taken at 1, 4, 7, 10, and 13 d after NaCl treatment to determine the morphology and physiological and biochemical indices of rice roots. The results showed that NaCl stress significantly inhibited rice growth; disrupted the antioxidant system; increased the rates of malondialdehyde, hydrogen peroxide, and superoxide anion production; and affected the content of related hormones. Malondialdehyde content, hydrogen peroxide content, and superoxide anion production rate significantly increased from 12.57% to 21.82%, 18.12% to 63.10%, and 7.17% to 56.20%, respectively, in the S treatment group compared to the CK group. Under salt stress, foliar sprays of both 5-ALA and DTA-6 increased antioxidant enzyme activities and osmoregulatory substance content; expanded non-enzymatic antioxidant AsA and GSH content; reduced reactive oxygen species (ROS) accumulation; lowered malondialdehyde content; increased endogenous hormones GA3, JA, IAA, SA, and ZR content; and lowered ABA content in the rice root system. The MDA, H2O2, and O2- contents were reduced from 35.64% to 56.92%, 22.30% to 53.47%, and 7.06% to 20.01%, respectively, in the AS treatment group compared with the S treatment group. In the DS treatment group, the MDA, H2O2, and O2- contents were reduced from 24.60% to 51.09%, 12.14% to 59.05%, and 12.70% to 45.20%. In summary, NaCl stress exerted an inhibitory effect on the rice root system, both foliar sprays of 5-ALA and DTA-6 alleviated damage from NaCl stress on the rice root system, and the effect of 5-ALA was better than that of DTA-6.


Assuntos
Antioxidantes , Oryza , Humanos , Antioxidantes/metabolismo , Plântula , Reguladores de Crescimento de Plantas/farmacologia , Peróxido de Hidrogênio/farmacologia , Cloreto de Sódio/farmacologia , Superóxidos/farmacologia , Estresse Oxidativo , Oxigênio/farmacologia , Hormônios/farmacologia , Malondialdeído/farmacologia
13.
Nucleic Acids Res ; 52(6): e30, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38346683

RESUMO

The CRISPR/Cas system has emerged as a powerful tool for genome editing in metabolic engineering and human gene therapy. However, locating the optimal site on the chromosome to integrate heterologous genes using the CRISPR/Cas system remains an open question. Selecting a suitable site for gene integration involves considering multiple complex criteria, including factors related to CRISPR/Cas-mediated integration, genetic stability, and gene expression. Consequently, identifying such sites on specific or different chromosomal locations typically requires extensive characterization efforts. To address these challenges, we have developed CRISPR-COPIES, a COmputational Pipeline for the Identification of CRISPR/Cas-facilitated intEgration Sites. This tool leverages ScaNN, a state-of-the-art model on the embedding-based nearest neighbor search for fast and accurate off-target search, and can identify genome-wide intergenic sites for most bacterial and fungal genomes within minutes. As a proof of concept, we utilized CRISPR-COPIES to characterize neutral integration sites in three diverse species: Saccharomyces cerevisiae, Cupriavidus necator, and HEK293T cells. In addition, we developed a user-friendly web interface for CRISPR-COPIES (https://biofoundry.web.illinois.edu/copies/). We anticipate that CRISPR-COPIES will serve as a valuable tool for targeted DNA integration and aid in the characterization of synthetic biology toolkits, enable rapid strain construction to produce valuable biochemicals, and support human gene and cell therapy applications.


Assuntos
Sistemas CRISPR-Cas , Biologia Computacional , Simulação por Computador , Edição de Genes , Humanos , Sistemas CRISPR-Cas/genética , Células HEK293 , Saccharomyces cerevisiae/genética , Biologia Computacional/métodos , Betaproteobacteria/genética , Interface Usuário-Computador
14.
Exp Lung Res ; 50(1): 25-41, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38419581

RESUMO

BACKGROUND: The transcriptional repressor B-cell lymphoma 6 (BCL6) has been reported to inhibit inflammation. So far, experimental evidence for the role of BCL6 in bronchopulmonary dysplasia (BPD) is lacking. Our study investigated the roles of BCL6 in the progression of BPD and its downstream mechanisms. METHODS: Hyperoxia or lipopolysaccharide (LPS) was used to mimic the BPD mouse model. To investigate the effects of BCL6 on BPD, recombination adeno-associated virus serotype 9 expressing BCL6 (rAAV9-BCL6) and BCL6 inhibitor FX1 were administered in mice. The pulmonary pathological changes, inflammatory chemokines and NLRP3-related protein were observed. Meanwhile, BCL6 overexpression plasmid was used in human pulmonary microvascular endothelial cells (HPMECs). Cell proliferation, apoptosis, and NLRP3-related protein were detected. RESULTS: Either hyperoxia or LPS suppressed pulmonary BCL6 mRNA expression. rAAV9-BCL6 administration significantly inhibited hyperoxia-induced NLRP3 upregulation and inflammation, attenuated alveolar simplification and dysregulated angiogenesis in BPD mice, which were characterized by decreased mean linear intercept, increased radical alveolar count and alveoli numbers, and the upregulated CD31 expression. Meanwhile, BCL6 overexpression promoted proliferation and angiogenesis, inhibited apoptosis and inflammation in hyperoxia-stimulated HPMECs. Moreover, administration of BCL6 inhibitor FX1 arrested growth and development. FX1-treated BPD mice exhibited exacerbation of alveolar pathological changes and pulmonary vessel permeability, with upregulated mRNA levels of pro-inflammatory cytokines and pro-fibrogenic factors. Furthermore, both rAAV9-BCL6 and FX1 administration exerted a long-lasting effect on hyperoxia-induced lung injury (≥4 wk). CONCLUSIONS: BCL6 inhibits NLRP3-mediated inflammation, attenuates alveolar simplification and dysregulated pulmonary vessel development in hyperoxia-induced BPD mice. Hence, BCL6 may be a target in treating BPD and neonatal diseases.


Assuntos
Displasia Broncopulmonar , Hiperóxia , Lesão Pulmonar , Animais , Humanos , Recém-Nascido , Camundongos , Animais Recém-Nascidos , Displasia Broncopulmonar/etiologia , Displasia Broncopulmonar/metabolismo , Modelos Animais de Doenças , Células Endoteliais/patologia , Hiperóxia/metabolismo , Inflamação/metabolismo , Lipopolissacarídeos/farmacologia , Pulmão/metabolismo , Lesão Pulmonar/tratamento farmacológico , Lesão Pulmonar/etiologia , Lesão Pulmonar/prevenção & controle , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Proteínas Proto-Oncogênicas c-bcl-6/metabolismo , RNA Mensageiro/metabolismo
15.
J Colloid Interface Sci ; 661: 943-956, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38330666

RESUMO

The step-scheme (S-scheme) heterojunction has excellent redox capability, effectively degrading organic pollutants in wastewater. Combining S-scheme heterojunction with activated persulfate advanced oxidation process reasonably can further enhance the degradation of Emerging Contaminants. Herein, a novel zero-dimensional/one-dimensional (0D/1D) CoO-CuBi2O4 (CoO-CBO) photocatalyst with S-scheme heterojunction was designed by hydrothermal and solvothermal methods. The band structure and electron and hole transfer pathway of CoO-CBO were analyzed using the ex-situ and in-situ X-ray photoelectron spectroscopy (XPS), Ultraviolet and Visible Spectrophotometer (UV-Vis) and optical radiation Kelvin probe force microscope (KPFM), and the formation of S-scheme heterojunction was demonstrated. The photocatalytic activity of ·S-scheme CoO-CBO heterojunction was carried out by degrading tetracycline (TC) with activating potassium monopersulfate triple salt under visible light. Compared with pure CuBi2O4 and pure CoO, 30%CoO/CuBi2O4 catalyst exhibited the highest TC degradation performance after activating persulfate, degrading 89.5% of TC within 90 min. On the one hand, the S-scheme heterojunction formed between CoO and CBO had a high redox potential. On the other hand, the activation of persulfate by Co and Cu could accelerate redox cycles and facilitate the generation of active radicals such as SO4-, O2- and OH, promoting the separation of the photogenerated e- and h+ in the composite, enhancing the peroxydisulfate (PDS) activation performance and improving the degradation effect of TC. Then, a gradual decrease in the toxicity of the intermediates in the TC degradation process was detected by ECOCER. In all, this study provided an S-scheme CoO/CuBi2O4 heterojunction that can activate PDS to degrade TC efficiently, which provided a new idea for the study of novel pollutant degradation and environmental toxicology.

17.
BMC Geriatr ; 24(1): 189, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38409011

RESUMO

BACKGROUND: There are a variety of determinants that are key to functional disability of older adults. However, little is known regarding the relationship between cognitive frailty and disability among older people. The aims of this study were to examine the associations between cognitive frailty and its six components with instrumental activities of daily living (IADL) functioning in community-dwelling older adults. METHODS: A total of 313 community-dwelling older adults (aged ≥ 65 years) were recruited from eight community centers in central China. Cognitive frailty was operationalized using the Mini-Mental State Examination for the evaluation of cognitive status and the Fried criteria for the evaluation of physical frailty. The outcome was functional disability assessed by the IADL scale. The association between cognitive frailty, as well as its components, and IADL limitations was identified by conducting binary logistic regression analysis. RESULTS: The prevalence of cognitive frailty was 8.9% in this study. The results showed that cognitive frailty (OR = 22.86) and frailty without cognitive impairment (OR = 8.15) were associated with IADL limitations. Subdimensions of cognitive frailty, exhaustion, weakness, low physical activity and cognitive impairment components were independently associated with IADL limitations. CONCLUSION: Cognitive frailty was associated with a higher prevalence of disability. Interventions for improving cognitive frailty should be developed to prevent IADL disability among community-dwelling older adults in China.


Assuntos
Fragilidade , Idoso , Humanos , Fragilidade/diagnóstico , Fragilidade/epidemiologia , Idoso Fragilizado/psicologia , Vida Independente/psicologia , Estudos Transversais , Atividades Cotidianas , China/epidemiologia , Cognição , Avaliação Geriátrica/métodos
18.
Colloids Surf B Biointerfaces ; 236: 113800, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38382226

RESUMO

The physicochemical characteristics of fatty acid (FA) vesicles and their ion sensitivity as drug delivery vehicles in an ion-competitive environment have received much attention. Here, we show that in a Na+/K+ competitive ionic environment, FA vesicles undergo a cascade of periodic expansion and selective ion retention in response to osmotic attack. When the Na+/K+ ratio is altered, the expansion and volume of vesicles are affected and the ions in vesicles mix with the hyperosmotic fluid to produce a stable transmembrane potential, consistent with the Donnan effect and iontophoresis theory. Furthermore, osmotic swelling experiments suggest that FA vesicles are more easily maintained in a single Na+ or K+ solution than in a multicomponent ion competition system. As a theoretical basis for the utilization of FA vesicles in multicomponent ionic environments, we developed a core theoretical model to characterize the basic features of the volume fluctuations of FA vesicles in ion-competing environments.


Assuntos
Ácidos Graxos , Modelos Teóricos , Osmose , Sódio , Íons
19.
Phytochemistry ; 220: 114012, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38311151

RESUMO

Penigrines A-E (1-5), five undescribed azepine-indole alkaloids, were isolated from the fungus Penicillium griseofulvum. Their structures with absolute configurations were determined by NMR, HRESIMS, ECD calculation, and X-ray diffraction experiments. Penigrine C (3) possesses an undescribed 6-oxa-8-azabicyclo[3.2.2]nonane-7,9-dione moiety that fused to an indole core, and penigrines D and E (4 and 5) are a pair of epimers. The plausible biosynthetic pathways of 1-5 are proposed. Penigrine A (1) shows the potential for heart failure treatment.


Assuntos
Alcaloides Indólicos , Penicillium , Alcaloides Indólicos/química , Penicillium/química , Espectroscopia de Ressonância Magnética , Fungos , Estrutura Molecular
20.
Metab Eng ; 82: 100-109, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38325640

RESUMO

Odd-numbered fatty acids (FAs) have been widely used in nutrition, agriculture, and chemical industries. Recently, some studies showed that they could be produced from bacteria or yeast, but the products are almost exclusively odd-numbered long-chain FAs. Here we report the design and construction of two biosynthetic pathways in Saccharomyces cerevisiae for de novo production of odd-numbered medium-chain fatty acids (OMFAs) via ricinoleic acid and 10-hydroxystearic acid, respectively. The production of OMFAs was enabled by introducing a hydroxy fatty acid cleavage pathway, including an alcohol dehydrogenase from Micrococcus luteus, a Baeyer-Villiger monooxygenase from Pseudomonas putida, and a lipase from Pseudomonas fluorescens. These OMFA biosynthetic pathways were optimized by eliminating the rate-limiting step, generating heptanoic acid, 11-hydroxyundec-9-enoic acid, nonanoic acid, and 9-hydroxynonanoic acid at 7.83 mg/L, 9.68 mg/L, 9.43 mg/L and 13.48 mg/L, respectively. This work demonstrates the biological production of OMFAs in a sustainable manner in S. cerevisiae.


Assuntos
Engenharia Metabólica , Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Ácidos Graxos , Oxigenases de Função Mista/metabolismo , Álcool Desidrogenase/metabolismo
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