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1.
Nat Mater ; 23(6): 755-761, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38605195

RESUMO

The strength-ductility trade-off has long been a Gordian knot in conventional metallic structural materials and it is no exception in multi-principal element alloys. In particular, at ultrahigh yield strengths, plastic instability, that is, necking, happens prematurely, because of which ductility almost entirely disappears. This is due to the growing difficulty in the production and accumulation of dislocations from the very beginning of tensile deformation that renders the conventional dislocation hardening insufficient. Here we propose that premature necking can be harnessed for work hardening in a VCoNi multi-principal element alloy. Lüders banding as an initial tensile response induces the ongoing localized necking at the band front to produce both triaxial stress and strain gradient, which enables the rapid multiplication of dislocations. This leads to forest dislocation hardening, plus extra work hardening due to the interaction of dislocations with the local-chemical-order regions. The dual work hardening combines to restrain and stabilize the premature necking in reverse as well as to facilitate uniform deformation. Consequently, a superior strength-and-ductility synergy is achieved with a ductility of ~20% and yield strength of 2 GPa during room-temperature and cryogenic deformation. These findings offer an instability-control paradigm for synergistic work hardening to conquer the strength-ductility paradox at ultrahigh yield strengths.

2.
Plant Physiol ; 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38753366

RESUMO

Sclerotinia disease is one of the most devastating fungal diseases worldwide, as it reduces the yields of many economically important crops. Pathogen-secreted effectors play crucial roles in infection processes. However, key effectors of Ciboria shiraiana, the pathogen primarily responsible for sclerotinia disease in mulberry (Morus spp.), remain poorly understood. In this study, we identified and functionally characterized the effector Cs02526 in C. shiraiana and found that Cs02526 could induce cell deathin a variety of plants. Moreover, Cs02526-induced cell death was mediated by the central immune regulator BRASSINOSTEROID INSENSITIVE 1-associated receptor kinase 1 (BAK1), dependent on a 67-amino acid fragment. Notably, Cs02526 homologues were widely distributed in hemibiotrophic and necrotrophic phytopathogenic fungi, but the homologues failed to induce cell death in plants. Pre-treatment of plants with recombinant Cs02526 protein enhanced resistance against both C. shiraiana and Sclerotinia sclerotiorum. Furthermore, the pathogenicity of C. shiraiana was diminished upon spraying plants with synthetic dsRNA-Cs02526. In conclusion, our findings highlight the cell death-inducing effector Cs02526 as a potential target for future biological control strategies against plant diseases.

3.
Mol Genet Genomic Med ; 12(4): e2433, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38591167

RESUMO

BACKGROUND: Kenny-Caffey syndrome type 2 (KCS2) is an extremely rare inherited disorder characterized by proportionate short stature, skeletal defects, ocular and dental abnormalities, and transient hypocalcemia. It is caused by variants in FAM111A gene. Diagnosis of KCS2 can be challenging because of its similarities to other syndromes, the absence of clear hallmarks and the deficient number of genetically confirmed cases. Here, we aimed to further delineate and summarize the genotype and phenotype of KCS2, in order to get a better understanding of this rare disorder, and promote early diagnosis and intervention. METHODS: We present clinical and genetic characteristics of eight newly affected individuals with KCS2 from six families, including one family with three individuals found to be a father-to-daughter transmission, adding to the limited literature. Furthermore, we performed a review of genetically confirmed KCS2 cases in PubMed, MEDLINE and CNKI databases. RESULTS: There were six females and two males in our cohort. All the patients presented with short stature (100.0%). Clinical manifestations included ocular defects such as hypermetropia (5/8), dental problems such as defective dentition (3/8) and dental caries (3/8), skeletal and brain anomalies such as delayed closure of anterior fontanelle (6/8), cerebral calcification (3/8), cortical thickening (3/8) and medullary stenosis (4/8) of tubular bones. Endocrinologic abnormalities included hypoparathyroidism (5/8) and hypocalcemia (3/8). One male patient had micropenis and microorchidism. All cases harboured missense variants of FAM111A, and nucleotides c.1706 arose as a mutational hotspot, with seven individuals harbouring a c.1706G>A (p.Arg569His) variant, and one child harbouring a c.1531T>C (p.Tyr511His) variant. Literature review yielded a total of 46 patients from 20 papers. Data analysis showed that short stature, hypoparathyroidism and hypocalcemia, ocular and dental defects, skeletal features including cortical thickening and medullary stenosis of tubular bones, and seizures/spasms were present in more than 70% of the reported KCS2 cases. CONCLUSION: We provide detailed characteristics of the largest KCS2 group in China and present the first genetically confirmed instance of father-to-daughter transmission of KCS2. Our study confirms that Arg569His is the hot spot variant and summarizes the typical phenotypes of KCS2, which would help early diagnosis and intervention.


Assuntos
Cárie Dentária , Nanismo , Hiperostose Cortical Congênita , Hipocalcemia , Hipoparatireoidismo , Criança , Feminino , Humanos , Masculino , Hipocalcemia/genética , Constrição Patológica , Fenótipo , Genótipo , Hipoparatireoidismo/genética
4.
Plant Sci ; 348: 112209, 2024 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-39098395

RESUMO

Transformation of plants using wild strains of agrobacteria is termed natural transformation and is not covered by GMO legislation in e.g. European Union and Japan. In the current study, offspring lines (A11 and B3) of Rhizobium rhizogenes naturally transformed oilseed rape (Brassica napus) were randomly selected to characterize the morphological traits, and analyze the implications of such morphological changes on plant drought resilience. It was found that the introduction of Ri-genes altered the biomass partitioning to above- and under-ground parts of oilseed rape plants. Compared to the wild type (WT), the A11 and B3 lines exhibited 1.2-4.0 folds lower leaf and stem dry weight, leaf area and plant height, but had 1.3-5.8 folds greater root dry weight, root length and root surface area, resulting in a significantly enhanced root: shoot dry mass ratio and root surface area: leaf area ratio. In addition, the introduction of Ri-genes conferred reduced stomatal pore aperture and increased stomatal density in the B3 line, and increased leaf thickness in A11 line, which could benefit plant drought resilience. Finally, the modulations in morphological traits as a consequence of transformation with Ri-genes are discussed concerning resilience in water-limited conditions. These findings reveal the potential of natural transformation with R. rhizogenes for drought-targeted breeding in crops.

5.
J Physiol Biochem ; 80(2): 303-315, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38175499

RESUMO

Lactate, an important exercise metabolite, induces white adipose tissue browning by upregulated uncoupling protein 1 (UCP1) expression. However, the function of lactate during browning of inguinal white adipose tissue (iWAT) caused by exercise is unclear. Here, we considered lactate as an exercise supplement and investigated the effects of chronic pre-exercise lactate administration on energy metabolism and adipose tissue browning. C57B/L6 male mice (5 weeks of age) were divided into six groups. We evaluated the changes in blood lactate levels in each group of mice after the intervention. Energy expenditure was measured after the intervention immediately by indirect calorimetry. The marker protein levels and gene expressions were determined by western-blot and quantitative real-time PCR. HIIT significantly decreased adipose tissue weight while increased energy expenditure and the expression of UCP1 in iWAT; however, these regulations were inhibited in the DCA+HIIT group. Compared with the MICT and LAC groups, long-term lactate injection before MICT led to lower WAT weight to body weight ratios and higher energy expenditure in mice. Furthermore, the marker genes of browning in iWAT, such as Ucp1 and Pparγ, were significantly increased in the LAC+MICT group than in the other groups, and the expression of monocarboxylate transporter-1 (Mct1) mRNA was also significantly increased. Lactate was involved in exercise-mediated browning of iWAT, and its mechanism might be the increased of lactate transport through MCT1 or PPARγ upregulation induced by exercise. These findings suggest exogenous lactate may be a new exercise supplement to regulate metabolism.


Assuntos
Tecido Adiposo Marrom , Tecido Adiposo Branco , Metabolismo Energético , Ácido Láctico , Camundongos Endogâmicos C57BL , Condicionamento Físico Animal , Simportadores , Proteína Desacopladora 1 , Animais , Masculino , Tecido Adiposo Branco/metabolismo , Ácido Láctico/metabolismo , Ácido Láctico/sangue , Tecido Adiposo Marrom/metabolismo , Proteína Desacopladora 1/metabolismo , Proteína Desacopladora 1/genética , Camundongos , Transportadores de Ácidos Monocarboxílicos/metabolismo , Transportadores de Ácidos Monocarboxílicos/genética , PPAR gama/metabolismo , PPAR gama/genética
6.
Nat Commun ; 15(1): 4036, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38740750

RESUMO

Microbial Ni2+ homeostasis underpins the virulence of several clinical pathogens. Ni2+ is an essential cofactor in urease and [NiFe]-hydrogenases involved in colonization and persistence. Many microbes produce metallophores to sequester metals necessary for their metabolism and starve competing neighboring organisms. The fungal metallophore aspergillomarasmine A (AMA) shows narrow specificity for Zn2+, Ni2+, and Co2+. Here, we show that this specificity allows AMA to block the uptake of Ni2+ and attenuate bacterial Ni-dependent enzymes, offering a potential strategy for reducing virulence. Bacterial exposure to AMA perturbs H2 metabolism, ureolysis, struvite crystallization, and biofilm formation and shows efficacy in a Galleria mellonella animal infection model. The inhibition of Ni-dependent enzymes was aided by Zn2+, which complexes with AMA and competes with the native nickelophore for the uptake of Ni2+. Biochemical analyses demonstrated high-affinity binding of AMA-metal complexes to NikA, the periplasmic substrate-binding protein of the Ni2+ uptake system. Structural examination of NikA in complex with Ni-AMA revealed that the coordination geometry of Ni-AMA mimics the native ligand, Ni-(L-His)2, providing a structural basis for binding AMA-metal complexes. Structure-activity relationship studies of AMA identified regions of the molecule that improve NikA affinity and offer potential routes for further developing this compound as an anti-virulence agent.


Assuntos
Proteínas de Bactérias , Níquel , Níquel/metabolismo , Níquel/química , Animais , Virulência/efeitos dos fármacos , Proteínas de Bactérias/metabolismo , Biofilmes/efeitos dos fármacos , Zinco/metabolismo , Zinco/química , Mariposas/microbiologia , Urease/metabolismo , Urease/antagonistas & inibidores , Transporte Biológico
7.
J Dent ; 146: 105041, 2024 07.
Artigo em Inglês | MEDLINE | ID: mdl-38762076

RESUMO

OBJECTIVES: This study aimed to measure the distribution of silver ion (Ag+), mineral recovery, and nanohardness in carious lesions and comprehensively evaluate the degree of dentin restoration. METHODS: Sixty human teeth with root caries were randomly assigned to the control, silver diammine fluoride (SDF) [Safo], and SDF+Glass ionomer cement (GIC) treatment [Safo+Fuji] groups. Micro-computed tomography (micro-CT) was performed at five time points for each sample before/after treatment to evaluate mineral density within and around carious lesions. Three months following treatment, 12 samples were selected for synchrotron radiation X-ray fluorescence analysis to evaluate Ag+ distribution, while 15 samples were selected for nanoindentation. Data were analyzed using Dunnett's T3 test for micro-CT and Wilcoxon rank sum test with Bonferroni correction (p = 0.017) for nanoindentation. The correlation between hardness and mineral change was analyzed using the Spearman rank correlation coefficient. RESULTS: The Safo and Safo+Fuji groups showed significantly higher mineral recovery rates than did the control group (p < 0.001). In the Safo group, Ag+ accumulated in the deeper layers rather than the superficial layer of caries. In the Safo+Fuji group, Ag+ was found evenly distributed throughout caries, with only a few Ag+ detected in the GIC layer. Hardness in the Safo+Fuji group was significantly higher compared with the Safo group at depths in the range of 10-50 µm. CONCLUSION: In the presence of GICs, SDF exhibited high remineralization capacity when diffusing throughout carious lesions over time. Combined treatment with SDF and GIC could strengthen root dentin even in the presence of caries. CLINICAL SIGNIFICANCE: We found that combination treatment with SDF and GIC could increase mineral density in caries and improve the hardness of the tooth structure compared with fluoride-based agents alone. These findings might pave the way for future clinical trials to determine the therapeutic potential of nanotechnology-based restorative materials.


Assuntos
Cariostáticos , Dentina , Cimentos de Ionômeros de Vidro , Dureza , Compostos de Amônio Quaternário , Cárie Radicular , Compostos de Prata , Prata , Microtomografia por Raio-X , Humanos , Cárie Radicular/tratamento farmacológico , Cimentos de Ionômeros de Vidro/química , Cimentos de Ionômeros de Vidro/uso terapêutico , Compostos de Prata/uso terapêutico , Microtomografia por Raio-X/métodos , Dentina/efeitos dos fármacos , Dentina/diagnóstico por imagem , Prata/uso terapêutico , Prata/química , Compostos de Amônio Quaternário/uso terapêutico , Cariostáticos/uso terapêutico , Fluoretos Tópicos/uso terapêutico , Remineralização Dentária/métodos , Restauração Dentária Permanente/métodos , Espectrometria por Raios X
8.
Int J Biol Macromol ; 271(Pt 2): 132467, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38763249

RESUMO

ß-Elemene, an important component of the volatile oil of Atractylodis macrocephala, has been widely utilized as an antitumor drug for over 20 years. However, the germacrene A synthase (GAS) genes responsible for the biosynthesis of ß-elemene in A. macrocephala were previously unidentified. In this study, two new AmGASs were identified from the A. macrocephala transcriptome, demonstrating their capability to convert farnesyl pyrophosphate into germacrene A, which subsequently synthesizes ß-elemene through Cope rearrangement. Additionally, two highly catalytic AmGAS1 mutations, I307A and E392A, resulted in a 2.23-fold and 1.57-fold increase in ß-elemene synthesis, respectively. Furthermore, precursor supply and fed-batch strategies were employed to enhance the precursor supply, resulting in ß-elemene yields of 7.3 mg/L and 33.3 mg/L, respectively. These findings identify a promising candidate GAS for ß-elemene biosynthesis and lay the foundation for further functional studies on terpene synthases in A. macrocephala.


Assuntos
Sesquiterpenos de Germacrano , Sesquiterpenos , Sesquiterpenos/metabolismo , Sesquiterpenos/química , Sesquiterpenos de Germacrano/metabolismo , Alquil e Aril Transferases/metabolismo , Alquil e Aril Transferases/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fosfatos de Poli-Isoprenil/metabolismo , Atractylodes/metabolismo , Atractylodes/química , Atractylodes/genética , Vias Biossintéticas , Transcriptoma
9.
Int J Biol Macromol ; 278(Pt 2): 134618, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39151851

RESUMO

Biomass-based slow-release fertilizers (SRFs) are a sustainable solution for addressing food scarcity, improving fertilizer efficiency, and reducing pollution, whereas they still face complex preparation, high costs, and low release characteristics. This study introduces a simple and innovative approach to producing bifunctional green SRFs with controlled release and conditioning properties for saline soils and harsh environments. The method involves a one-pot preparation of microsphere-structured amine-modified lignin slow-release fertilizer (L-UX) using biomass lignin as the starting material. The L-UX demonstrates an exceptional fertilizer loading rate (66.2 %) and extended slow-release performance (288 h), effectively enhancing the fertilizer's release ability. Compared to traditional fertilizers, the bifunctional L-UX significantly improves soil water retention capacity (824.3 %), plant growth, and germination percentage in challenging soil conditions (133 %). These findings highlight the potential of L-UX as a large-scale controlled-release fertilizer in harsh environments. A life cycle assessment (LCA) was also conducted to evaluate the environmental impact of L-UX from its production to disposal. This revealed that L-UX has a minimal environmental footprint compared to conventional inorganic fertilizers. This study further supports the widespread application of L-UX as an environmentally friendly alternative.

10.
Int J Biol Macromol ; 276(Pt 1): 133799, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39019367

RESUMO

The performance of cellulose-based materials is highly dependent on the choice of solvent systems. Exceptionally, cellulose dissolution and derivatization by efficient solvent have been considered as a key factor for large-scale industrial applications of cellulose. However, cellulose dissolution and derivatization often requires harsh reaction conditions, high energy consumption, and complex solubilizing, resulting in environmental impacts and low practical value. Here we address these limitations by using a low-temperature oxalic acid/sulfuric acid solvent to enable cellulose dissolution and derivatization for high-performance cellulose films. The dissolution and derivatization mechanism of the mixed acid is studied, demonstrating that cellulose is firstly socked by oxalic acid, then more hydrogen bonds ionized by sulfuric acid break cellulose chain, and finally the esterification reaction between oxalic acid and cellulose is catalyzed by sulfuric acid. Solutions containing 8 %-10 % cellulose are obtained and can be stored for a long time at -18 °C without significant degradation. Moreover, the cellulose film exhibits a higher tensile strength of up to 66.1 MPa, thermal stability, and degree of polymerization compared to that fabricated by sulfuric acid. These unique advantages provide new paths to utilize renewable resources for alternative food packaging materials at an industrial scale.


Assuntos
Celulose , Embalagem de Alimentos , Ácido Oxálico , Ácidos Sulfúricos , Ácidos Sulfúricos/química , Celulose/química , Embalagem de Alimentos/métodos , Ácido Oxálico/química , Resistência à Tração , Solubilidade , Solventes/química
11.
ACS Nano ; 18(9): 7011-7023, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38390865

RESUMO

Ferroptotic cancer therapy has been extensively investigated since the genesis of the ferroptosis concept. However, the therapeutic efficacy of ferroptosis induction in heterogeneous and plastic melanoma has been compromised, because the melanocytic and transitory cell subpopulation is resistant to iron-dependent oxidative stress. Here, we report a phenotype-altering liposomal nanomedicine to enable the ferroptosis-resistant subtypes of melanoma cells vulnerable to lipid peroxidation via senescence induction. The strategy involves the ratiometric coencapsulation of a cyclin-dependent kinase 4 and 6 (CDK4/6) inhibitor (palbociclib) and a ferroptosis inducer (auranofin) within cRGD peptide-modified targeted liposomes. The two drugs showed a synergistic anticancer effect in the model B16F10 melanoma cells, as evidenced by the combination index analysis (<1). The liposomes could efficiently deliver both drugs into B16F10 cells in a targeted manner. Afterward, the liposomes potently induced the intracellular redox imbalance and lipid peroxidation. Palbociclib significantly provoked cell cycle arrest at the G0/G1 phase, which sensitized auranofin-caused ferroptosis through senescence induction. Meanwhile, palbociclib depleted intracellular glutathione (GSH) and reduced nicotinamide adenine dinucleotide phosphate (NADPH), further boosting ferroptosis. The proof-of-concept was also demonstrated in the B16F10 tumor-bearing mice model. The current work offers a promising ferroptosis-targeting strategy for effectively treating heterogeneous melanoma by manipulating the cellular plasticity.


Assuntos
Ferroptose , Melanoma , Animais , Camundongos , Melanoma/tratamento farmacológico , Lipossomos/farmacologia , Coenzimas/farmacologia , Auranofina/farmacologia , Peroxidação de Lipídeos
12.
Front Genet ; 15: 1398240, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38988837

RESUMO

Background: Schizophrenia (SCZ) is a severe neurodevelopmental disorder with brain dysfunction. This study aimed to use bioinformatic analysis to identify candidate blood biomarkers for SCZ. Methods: The study collected peripheral blood leukocyte samples of 9 SCZ patients and 20 healthy controls for RNA sequencing analysis. Bioinformatic analyses included differentially expressed genes (DEGs) analysis, pathway enrichment analysis, and weighted gene co-expression network analysis (WGCNA). Results: This study identified 1,205 statistically significant DEGs, of which 623 genes were upregulated and 582 genes were downregulated. Functional enrichment analysis showed that DEGs were mainly enriched in cell chemotaxis, cell surface, and serine peptidase activity, as well as involved in Natural killer cell-mediated cytotoxicity. WGCNA identified 16 gene co-expression modules, and five modules were significantly correlated with SCZ (p < 0.05). There were 106 upregulated genes and 90 downregulated genes in the five modules. The top ten genes sorted by the Degree algorithm were RPS28, BRD4, FUS, PABPC1, PCBP1, PCBP2, RPL27A, RPS21, RAG1, and RPL27. RAG1 and the other nine genes belonged to the turquoise and pink module respectively. Pathway enrichment analysis indicated that these 10 genes were mainly involved in processes such as Ribosome, cytoplasmic translation, RNA binding, and protein binding. Conclusion: This study finds that the gene functions in key modules and related enrichment pathways may help to elucidate the molecular pathogenesis of SCZ, and the potential of key genes to become blood biomarkers for SCZ warrants further validation.

13.
Hortic Res ; 11(6): uhae120, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38919559

RESUMO

Understanding the intricate regulatory mechanisms underlying the anthocyanin content (AC) in fruits and vegetables is crucial for advanced biotechnological customization. In this study, we generated high-quality haplotype-resolved genome assemblies for two mulberry cultivars: the high-AC 'Zhongsang5801' (ZS5801) and the low-AC 'Zhenzhubai' (ZZB). Additionally, we conducted a comprehensive analysis of genes associated with AC production. Through genome-wide association studies (GWAS) on 112 mulberry fruits, we identified MaVHAG3, which encodes a vacuolar-type H+-ATPase G3 subunit, as a key gene linked to purple pigmentation. To gain deeper insights into the genetic and molecular processes underlying high AC, we compared the genomes of ZS5801 and ZZB, along with fruit transcriptome data across five developmental stages, and quantified the accumulation of metabolic substances. Compared to ZZB, ZS5801 exhibited significantly more differentially expressed genes (DEGs) related to anthocyanin metabolism and higher levels of anthocyanins and flavonoids. Comparative analyses revealed expansions and contractions in the flavonol synthase (FLS) and dihydroflavonol 4-reductase (DFR) genes, resulting in altered carbon flow. Co-expression analysis demonstrated that ZS5801 displayed more significant alterations in genes involved in late-stage AC regulation compared to ZZB, particularly during the phase stage. In summary, our findings provide valuable insights into the regulation of mulberry fruit AC, offering genetic resources to enhance cultivars with higher AC traits.

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