Rift Valley fever virus coordinates the assembly of a programmable E3 ligase to promote viral replication.

Viruses encode strategies to degrade cellular proteins to promote infection and pathogenesis. Here, we revealed that the non-structural protein NSs of Rift Valley fever virus forms a filamentous E3 ligase to trigger efficient degradation of targeted proteins. Reconstitution in vitro and cryoelectron microscopy analysis with the 2.9-Å resolution revealed that NSs forms right-handed helical fibrils. The NSs filamentous oligomers associate with the cellular FBXO3 to form a remodeled E3 ligase. The NSs-FBXO3 E3 ligase targets the cellular TFIIH complex through the NSs-P62 interaction, leading to ubiquitination and proteasome-dependent degradation of the TFIIH complex. NSs-FBXO3-triggered TFIIH complex degradation resulted in robust inhibition of antiviral immunity and promoted viral pathogenesis in vivo. Furthermore, it is demonstrated that NSs can be programmed to target additional proteins for proteasome-dependent degradation, serving as a versatile targeted protein degrader. These results showed that a virulence factor forms a filamentous and programmable degradation machinery to induce organized degradation of cellular proteins to promote viral infection.

Language proficiency is associated with neural representational dimensionality of semantic concepts.

Previous studies suggest that semantic concepts are characterized by high-dimensional neural representations and that language proficiency affects semantic processing. However, it is not clear whether language proficiency modulates the dimensional representations of semantic concepts at the neural level. To address this question, the present study adopted principal component analysis (PCA) and representational similarity analysis (RSA) to examine the differences in representational dimensionalities (RDs) and in semantic representations between words in highly proficient (Chinese) and less proficient (English) language. PCA results revealed that language proficiency increased the dimensions of lexical representations in the left inferior frontal gyrus, temporal pole, inferior temporal gyrus, supramarginal gyrus, angular gyrus, and fusiform gyrus. RSA results further showed that these regions represented semantic information and that higher semantic representations were observed in highly proficient language relative to less proficient language. These results suggest that language proficiency is associated with the neural representational dimensionality of semantic concepts.

Mechanistic insights into copper-mediated benzylic C(sp3)-H bond trifluoromethylation.

The mechanisms underlying copper-mediated trifluoromethylation of benzylic C(sp3)-H bonds were investigated using density functional theory (DFT) calculations. Two distinct pathways were identified: radical recombination/reductive elimination and single-electron transfer (SET). In the radical recombination/reductive elimination pathway, the CuII species recombines with benzyl radicals to generate a CuIII intermediate, which subsequently undergoes reductive elimination. Conversely, the SET pathway involves single-electron transfer from benzyl radicals to CuII species, forming a cationic benzylic intermediate and CuI species, followed by coupling with a CF3 group coordinated to Cu. DFT calculations revealed that the radical recombination/reductive elimination pathway is favoured for trifluoromethylation of primary and secondary benzylic C(sp3)-H bonds, with the reductive elimination step being rate-determining. In contrast, the SET pathway exhibits preference for trifluoromethylation of tertiary benzylic C(sp3)-H bonds. These mechanistic insights have significant implications for enhancing the selectivity of copper-mediated trifluoromethylation reactions.

Comprehensive Screening and Validation of Stable Internal Reference Genes for Accurate qRT-PCR Analysis in Holotrichia parallela under Diverse Biological Conditions and Environmental Stresses.

Holotrichia parallela is among the world's most destructive pests. For accurate qPCR and gene expression studies, the selection of stable and appropriate reference genes is crucial. However, a thorough evaluation of potential reference genes for use in H. parallela research is lacking. In this study, 11 reference genes (GAPDH, RPL32, RPL7A, RPS18, RPL13a, RPL18, Actin, RPS7, RPS3, VATB,and EF1A) were evaluated under different biological conditions and environmental stresses. The stability of 11 potential reference gene transcripts was evaluated through various computational tools, including geNorm, BestKeeper, NormFinder, theΔCt method, and the RefFinder program. Under various developmental stages and RNAi conditions, RPL18 and RPL13a exhibited the greatest stability. RPL13a, RPL18, and RPL32 were the most stable genes in both male and female adults. Under differing tissue conditions, RPL13a and RPS3 stood out as the most reliable. Moreover, under varying photoperiod conditions, RPL13a, RPS3 and RPL32 were the most stable genes. Lastly, Actin and RPL13a were the most stable genes across different temperatures. These findings offer essential criteria for selecting suitable reference genes across diverse experimental settings, thereby establishing a solid basis for accurate gene expression studies in H. parallela using RT-qPCR.

Latent profile analysis of empathy ability and its relationship with professional quality of life among hospice nurses in China.

BACKGROUND: Empathy is important in hospice nursing clinics and may influence nurses' professional quality of life (ProQOL). However, present studies ignoring each empathic dimension, and few researches have explored the correlation between empathy and ProQOL in hospice nurses in Asia. To better understand hospice nurses' empathy abilities in China and its relationship with ProQOL, the aim of this study was to identify the latent profiles and its influencing factors of hospice nurses' empathy ability, as well as differences in ProQOL across each latent profile. METHODS: A cross-sectional study was conducted from October 2021 to September 2022, and a total of 725 hospice nurses were recruited from different geographic regions in China. Participants completed the Empathy Ability Scale for Hospice Nurses and the Brief Professional Quality of Life Scale. Latent profile analysis (LPA) was employed to identify latent profiles of empathy ability among hospice nurses in China. The predictors of hospice nurses' empathy ability in different latent profiles were assessed using multinomial logistic regression analysis. One-way ANOVA test and the Kruskal-Wallis test were used to compare the ProQOL scores in each latent profile of nurses' empathy ability. RESULTS: This study identified three latent profiles of hospice nurses' empathy ability, and those profiles labelled "poor empathy ability-high surface empathy expression" (n = 216, 29.8%), "moderate empathy ability" (n = 359, 49.5%) and "high empathy ability-high deep empathy expression" (n = 150, 20.7%). Multinomial logistic regression analysis suggested that age, hospital level, whether income meets expectations, interests in hospice care work, hospice work experience, and receiving psychological counselling were predictors of hospice nurses' profile membership of empathy ability. The scores of compassion satisfaction (CS) and burnout (BO) in ProQOL were significantly different across each profile (P < 0.001), while scores of secondary traumatic stress (STS) in ProQOL were not different across each profile (P = 0.294). CONCLUSIONS: Hospice nurses' empathy ability was divided into three latent profiles, and enhancing empathy ability may be conducive to improving hospice nurses' CS, while reducing BO, thus fostering their overall quality of life. Nursing managers should identify hospice nurses at higher risk of BO and implement targeted interventions focused on enhancing nurse's empathy abilities.

Genome-Wide Characterization and Analysis of the SPL Gene Family in Eucalyptus grandis.

SQUAMOSA promoter-binding protein-like (SPL) gene family, a group of plant-specific transcription factors, played crucial roles in regulating plant growth, development, signal transduction, and stress response. This study focuses on the SPL gene family in the fast-growing Eucalyptus grandis, employing bioinformatics approaches to identify and analyze the gene physiochemical characteristics, conserved domains, structural composition, chromosomal distribution, phylogenetic relationships, cis-acting elements, and their expression patterns in various tissues and stress treatments. Twenty-three SPL genes were identified in E. grandis, which uneven distributed across seven chromosomes and classified into five groups. Prediction of cis-acting elements revealed that these genes might be related to light, hormone, and stress responses. Furthermore, EgSPL9 and EgSPL23, mainly expressed in the stem apex and lateral branches, seem to be involved in hormone stress resistance. Our study provides insights into the potential functions of the EgSPL genes in plant growth, stress response, and hormone transduction, offering valuable perspectives for subsequent research into their biological roles.

Characterization of Lomofungin Gene Cluster Enables the Biosynthesis of Related Phenazine Derivatives.

Phenazine-based small molecules are nitrogen-containing heterocyclic compounds with diverse bioactivities and electron transfer properties that exhibit promising applications in pharmaceutical and electrochemical industries. However, the biosynthetic mechanism of highly substituted natural phenazines remains poorly understood. In this study, we report the direct cloning and heterologous expression of the lomofungin biosynthetic gene cluster (BGC) from Streptomyces lomondensis S015. Reconstruction and overexpression of the BGCs in Streptomyces coelicolor M1152 resulted in eight phenazine derivatives including two novel hybrid phenazine metabolites, and the biosynthetic pathway of lomofungin was proposed. Furthermore, gene deletion suggested that NAD(P)H-dependent oxidoreductase gene lomo14 is a nonessential gene in the biosynthesis of lomofungin. Cytotoxicity evaluation of the isolated phenazines and lomofungin was performed. Specifically, lomofungin shows substantial inhibition against two human cancer cells, HCT116 and 5637. These results provide insights into the biosynthetic mechanism of lomofungin, which will be useful for the directed biosynthesis of natural phenazine derivatives.

Overexpression of PRDM16 attenuates acute kidney injury progression: genetic and pharmacological approaches.

Acute kidney injury (AKI) presents as a condition marked by a sudden and rapid decrease in kidney function over a short timeframe, resulting from diverse causes. As a transcription factor, PR domain-containing 16 (PRDM16), has recently been implicated in brown fat biogenesis and heart diseases. Our recent works indicated that PRDM16 could suppress the occurrence of renal interstitial fibrosis in diabetic kidney disorder. Nonetheless, the effect and regulatory mechanism of PRDM16 in AKI remain elusive. Our study demonstrated that PRDM16 inhibited apoptosis induced by ischemic/reperfusion (I/R) in BUMPT (Boston University mouse kidney proximal tubular) cells and HK-2(Human Kidney-2) cells. Mechanistically, PRDM16 not only bound to the promoter region of S100 Calcium Binding Protein A6 (S100A6)and upregulated its expression but also interacted with its amino acids 945-949, 957-960, and 981-984 to suppress the p38MAPK and JNK axes via inhibition of PKC-η activity and mitochondrial reactive oxygen species (ROS) production. Furthermore, cisplatin- and I/R-stimulated AKI progression were ameliorated in PRDM16 proximal-tubule-specific knockin mice, whereas exacerbated in PRDM16 knockout proximal-tubule-specific mice). Moreover, we observed that formononetin ameliorated I/R- and cisplatin-triggered AKI progression in mice. Taken together, these findings reveal a novel self-protective mechanism in AKI, whereby PRDM16 regulates the S100A6/PKC-η/ROS/p38MAPK and JNK pathways to inhibit AKI progression.

RVFV virulence factor NSs triggers the mitochondrial MCL-1-BAK axis to activate pathogenic NLRP3 pyroptosis.

Infection of Rift Valley fever virus (RVFV), a highly pathogenic mosquito-borne zoonotic virus, triggers severe inflammatory pathogenesis but the underlying mechanism of inflammation activation is currently unclear. Here, we report that the non-structural protein NSs of RVFV triggers mitochondrial damage to activate the NLRP3 inflammasome leading to viral pathogenesis in vivo. It is found that the host transcription inhibition effect of NSs causes rapid down-regulation of myeloid cell leukemia-1(MCL-1), a pro-survival member of the Bcl-2 (B-cell lymphoma protein 2) protein family. MCL-1 down-regulation led to BAK activation in the mitochondria, which triggered mtROS production and release of oxidized mitochondrial DNA (ox-mtDNA) into the cytosol. Cytosolic ox-mtDNA binds and activates the NLRP3 inflammasome triggering NLRP3-GSDMD pyroptosis in RVFV infected cells. A NSs mutant virus (RVFV-NSsRM) that is compromised in inducing transcription inhibition did not trigger MCL-1 down-regulation nor NLRP3-GSDMD pyroptosis. RVFV infection of the Nlrp3-/- mouse model demonstrated that the RVFV-triggered NLRP3 pyroptosis contributed to RVFV inflammatory pathogenesis and fatal infection in vivo. Infection with the RVFV-NSsRM mutant virus similarly showed alleviated inflammatory pathogenesis and reduced fatality rate. Taken together, these results revealed a mechanism by which a virulence factor activates the mitochondrial MCL-1-BAK axis through inducing host transcription inhibition to trigger NLRP3-dependent inflammatory pathogenesis.

Adam19 Deficiency Impacts Pulmonary Function: Human GWAS Follow-up in a Mouse Knockout Model.

PURPOSE: Over 550 loci have been associated with human pulmonary function in genome-wide association studies (GWAS); however, the causal role of most remains uncertain. Single nucleotide polymorphisms in a disintegrin and metalloprotease domain 19 (ADAM19) are consistently related to pulmonary function in GWAS. Thus, we used a mouse model to investigate the causal link between Adam19 and pulmonary function. METHODS: We created an Adam19 knockout (KO) mouse model and validated the gene targeting using RNA-Seq and RT-qPCR. Mouse body composition was assessed using dual-energy X-ray absorptiometry. Mouse lung function was measured using flexiVent. RESULTS: Contrary to prior publications, the KO was not neonatal lethal. KO mice had lower body weight and shorter tibial length than wild-type (WT) mice. Their body composition revealed lower soft weight, fat weight, and bone mineral content. Adam19 KO had decreased baseline respiratory system elastance, minute work of breathing, tissue damping, tissue elastance, and forced expiratory flow at 50% forced vital capacity but higher FEV0.1 and FVC. Adam19 KO had attenuated tissue damping and tissue elastance in response to methacholine following LPS exposure. Adam19 KO also exhibited attenuated neutrophil extravasation into the airway after LPS administration compared to WT. RNA-Seq analysis of KO and WT lungs identified several differentially expressed genes (Cd300lg, Kpna2, and Pttg1) implicated in lung biology and pathogenesis. Gene set enrichment analysis identified negative enrichment for TNF pathways. CONCLUSION: Our murine findings support a causal role of ADAM19, implicated in human GWAS, in regulating pulmonary function.

Genome-wide analysis and identification of the TBL gene family in Eucalyptus grandis.

The TRICHOME BIREFRINGENCE-LIKE (TBL) gene encodes a class of proteins related to xylan acetylation, which has been shown to play an important role in plant response to environmental stresses. This gene family has been meticulously investigated in Arabidopsis thaliana, whereas there have been no related reports in Eucalyptus grandis. In this study, we identified 49 TBL genes in E. grandis. A conserved amino acid motif was identified, which plays an important role in the execution of the function of TBL gene family members. The expression of TBL genes was generally upregulated in jasmonic acid-treated experiments, whereas it has been found that jasmonic acid activates the expression of genes involved in the defense functions of the plant body, suggesting that TBL genes play an important function in the response of the plant to stress. The principle of the action of TBL genes is supported by the finding that the xylan acetylation process increases the rigidity of the cell wall of the plant body and thus improves the plant's resistance to stress. The results of this study provide new information about the TBL gene family in E. grandis and will help in the study of the evolution, inheritance, and function of TBL genes in E. grandis, while confirming their functions.

Genome-Wide Identification and Functional Analysis of the GUX Gene Family in Eucalyptus grandis.

Xylan, one of the most important structures and polysaccharides, plays critical roles in plant development, growth, and defense responses to pathogens. Glucuronic acid substitution of xylan (GUX) functions in xylan sidechain decoration, which is involved in a wide range of physiological processes in plants. However, the specifics of GUXs in trees remain unclear. In this study, the characterization and evolution of the GUX family genes in E. grandis, a fast-growing forest tree belonging to the Myrtaceae family, were performed. A total of 23 EgGUXs were identified from the E. grandis genome, of which all members contained motif 2, 3, 5, and 7. All GUX genes were phylogeneticly clustered into five distinct groups. Among them, EgGUX01~EgGUX05 genes were clustered into group III and IV, which were more closely related to the AtGUX1, AtGUX2, and AtGUX4 members of Arabidopsis thaliana known to possess glucuronyltransferase activity, while most other members were clustered into group I. The light-responsive elements, hormone-responsive elements, growth and development-responsive elements, and stress-responsive elements were found in the promoter cis-acting elements, suggesting the expression of GUX might also be regulated by abiotic factors. RNA-Seq data confirmed that EgGUX02, EgGUX03, and EgGUX10 are highly expressed in xylem, and EgGUX09, EgGUX10, and EgGUX14 were obviously responses to abiotic stresses. The results of this paper will provide a comprehensive determination of the functions of the EgGUX family members, which will further contribute to understanding E. grandis xylan formation.

Remimazolam in General Anesthesia: A Comprehensive Review of Its Applications and Clinical Efficacy.

Remimazolam is a novel ultra-short-acting benzodiazepine with a unique pharmacokinetic profile that makes it an attractive option for use in general anesthesia. This review paper provides an in-depth analysis of remimazolam's applications in the field of general anesthesia, focusing on its pharmacological properties, clinical efficacy, safety profile, and potential advantages compared to other anesthetic agents. Remimazolam acts on GABAa receptors, offering rapid onset and recovery times due to its unique metabolic pathway involving tissue esterases. Clinical trials have demonstrated its efficacy in procedural sedation and general anesthesia, showing a favorable safety profile with minimal cardiovascular and respiratory depression. Compared to traditional anesthetics such as propofol, remimazolam presents distinct advantages, including predictable pharmacokinetics, reduced risk of prolonged sedation, and a reliable safety margin. These attributes position remimazolam as a promising agent in various clinical settings. The purpose of this review is to synthesize current evidence on remimazolam and discuss its potential to improve clinical outcomes in anesthesia practice.

Construction of H-Doped PdB Nanocrystals as Electrocatalysts to Modulate Formic Acid Oxidation.

The strong ligand effect in B-doped Pd-based (PdB) catalysts renders them a promising anode for constructing formic acid fuel cells (FAFCs) exhibiting high power density and outstanding stability. However, the enhancement of the oxidation barrier is unavoidable in this alloy system owing to the electron transfer (ET) from B to Pd. In this study, a hydrogen doping strategy is employed to open charge freedom in PdB compounds and boost their formic acid oxidation reaction (FAOR) activity by suppressing the ET process. The resulting hydrogen-doped PdB (PdBH) exhibits an ultrahigh mass activity of up to 1.2A mg-1 Pd, which is 3.23 times that of the PdB catalyst and 9.55 times that of Pd black. Detailed experimental and theoretical studies show that the interstitial hydrogen leads to enhanced orbital hybridization and reduced electron density around Pd. This optimized ligand effect weakens the carbon monoxide adsorption and increases the direct pathway preference of PdBH, resulting in its outstanding catalytic activity for the FAOR. The development of this high-performance hydrogen-doped PdB catalyst is an important step toward the construction of advanced light element co-doped metal catalysts.

Triiodothyronine (T3) suppresses hepatic tumorigenesis and development by inhibiting the phosphorylation of ERK.

The effect of triiodothyronine (T3) on the phosphorylation of ERK and the occurrence and development of hepatocellular carcinoma (HCC) is controversial and remains to be clarified. In the present study, both in vitro (hepatoma cell lines) and in vivo (wild-type mice [WT] and mouse models of HCC [HrasG12Vand KrasG12Dtransgenic mice (Hras-Tg and Kras-Tg)]) systems were used to investigate the effect of T3 on p-ERK and hepatocarcinogenesis. The results showed that, in vitro, T3 treatment elevated the levels of p-ERK in hepatoma cells within 30 min. However, p-ERK levels returned to normal after 1 h with no significant effects on cellular proliferation or apoptosis. Interestingly, in vivo, T3 induced early rapid and transient activation of ERK and later persistent downregulation of p-ERK in liver tissues of WT. In Hras-Tg, liver weight, liver/body weight ratio, hepatic tumor numbers and sizes were significantly reduced withT3treatment compared with the untreated group. Furthermore, the levels of albumin, HrasG12V, and p-ERK in hepatic precancerous and tumor tissues were all significantly downregulated with T3 treatment; however, the levels of endogenous Hras were not affected. In WT, T3 also induced downregulation of Albumin in liver tissues, but without influence on the expression of endogenous Hras and p-MEK. Especially, the inhibitory effect of T3 on p-ERK and hepatic tumorigenesis and development without influence on the levels of KrasG12D and p-MEK was further confirmed in Kras-Tg. In conclusion, T3 suppresses hepatic tumorigenesis and development by independently and substantially inhibiting the phosphorylation of ERK in vivo.

A fluorescence aptamer sensor utilizing WS2 nanosheets for sensitive detection of patulin: enhanced specificity and wide applicability.

A tungsten disulfide (WS2) nanosheet-based aptamer sensor was developed to detect patulin (PAT). The 5'-end of the PAT aptamer was modified with a cyanine 3 (Cy3) fluorophore, which self-assembled on WS2 nanosheets. The interaction between the Cy3 fluorophore at the 5'-end of the PAT aptamer and the WS2 nanosheets resulted in reduced fluorescence (FL) intensity due to fluorescence resonance energy transfer (FRET). The introduction of PAT into this sensing system led to hybridization with the PAT aptamer, forming a G-quadruplex/PAT complex with low affinity for the WS2 nanosheet surface. This hybridization increased the distance between the Cy3 fluorophore and the WS2 nanosheets, inhibiting FRET and producing a strong FL signal. Under optimal experimental conditions, the FL intensity of the sensing system demonstrated an excellent linear correlation with PAT concentrations ranging from 0.5 to 40.0 ng mL-1, and it achieved a detection limit (S/N = 3) of 0.23 ng mL-1. This sensing system offers enhanced specificity for PAT detection and has the potential for broad application in detecting other toxins by substituting the sequence of the recognition aptamer.

Symptom Clusters in Children With Leukemia Receiving Chemotherapy: A Scoping Review.

BACKGROUND: Leukemia represents the most prevalent childhood malignancy. Understanding the symptom clusters (SCs) associated with leukemia may help develop an effective care plan for affected children. OBJECTIVES: The aims of this study were to summarize the methods of identifying SCs; ascertain the types, attributes, and changing patterns of SCs during different chemotherapy phases; and provide a point of reference for the subsequent improvement of symptom management in pediatric leukemia. METHODS: The methodological framework employed was the Joanna Briggs Institute Scoping Review Guide. A comprehensive search was conducted across various databases, including PubMed, EMBASE, CINAHL, Web of Science, MEDLINE, Scopus, and China National Knowledge Infrastructure from inception until July 15, 2023. RESULTS: A total of 14 articles were included in this review, 6 in English and 8 in Chinese. The Memorial Symptom Assessment Scale 10-18 is the most commonly used instrument, whereas factor analysis is the most common statistical method for SC identification. The SCs were classified into 12 categories. The most severe SCs varied across different phases. Specifically, the emotional cluster dominated the prechemotherapy phase, the gastrointestinal cluster surfaced during postinduction therapy, and the consolidation and maintenance therapy phases revealed the self-image disorder cluster. CONCLUSION: Various consistent and dynamic SCs manifest among pediatric patients with leukemia undergoing chemotherapy. IMPLICATIONS FOR PRACTICE: Future research endeavors should formulate clear criteria to determine the stability and consistency of SCs, validate SC composition and characteristics, and devise precise symptom management protocols based on SC characteristics in the distinct chemotherapy phases.

An ultrasensitive solid-state electrochemiluminescence sensor based on Ni-MOF@Ru(bpy)32+ and Au NPs@TiO2 for determination of permethrin.

The novel TiO2 and Ni-MOF materials were synthesized and utilized for the detection of permethrin (PET). A highly sensitive solid-state electrochemiluminescence (ECL) sensor was developed based on Ni-MOF@Ru(bpy)32+ and Au NPs@TiO2. In this sensing platform, Ru(bpy)32+-Tripropyl Amine (TPrA) was used as a luminescent signal, Ni-MOF acted as a carrier to carry more luminescent reagents Ru(bpy)32+. Au NPs acted as promoters facilitated electron transport and TiO2 could further enhance the luminescence intensity of the system by synergistical interaction with Au NPs. The possible mechanisms of signal amplification were investigated. The ECL intensity decreased significantly with increasing PET concentration, enabling the determination of PET amount through the observation of the change in ECL signal intensity (ΔI). Under optimal experimental conditions, the linear range of PET concentration from 1.0 × 10-11 mol L-1 to 1.0 × 10-6 mol L-1, with a detection limit of 3.3 × 10-12 mol L-1 (3S/N). This method was successfully applied to determine PET in various vegetable samples.

Understanding the dynamic evolution of hemicellulose during Pinus taeda L. growth.

Pinus taeda L. is a fast-growing softwood with significant commercial value. Understanding structural changes in hemicellulose during growth is essential to understanding the biosynthesis processes occurring in the cell walls of this tree. In this study, alkaline extraction is applied to isolate hemicellulose from Pinus taeda L. stem segments of different ages (1, 2, 3, and 4 years old). The results show that the extracted hemicellulose is mainly comprised of O-acetylgalactoglucomannan (GGM) and 4-O-methylglucuronoarabinoxylan (GAX), with the molecular weights and ratios (i.e., GGM:GAX) of GGM and GAX increasing alongside Pinus taeda L. age. Mature Pinus taeda L. hemicellulose is mainly composed of GGM, and the ratio of (mannose:glucose) in the GGM main chain gradually increases from 2.45 to 3.60 with growth, while the galactose substitution of GGM decreases gradually from 21.36% to 14.65%. The acetylation of GGM gradually increases from 0.33 to 0.45 with the acetyl groups mainly substituting into the O-3 position in the mannan. Furthermore, the contents of arabinose and glucuronic acid in GAX gradually decrease with growth. This study can provide useful information to the research in genetic breeding and high-value utilization of Pinus taeda L.

A reliable fluorescence "turn-on" aptasensor based on dual-emitting europium metal-organic frameworks for ultrasensitive and selective detection of sulfamethazine.

A high-performance fluorescent "turn-on" aptasensor (Eu-MOFs@SMZ-Apt) for sulfamethazine (SMZ) determination was designed using dual-emitting europium metal-organic frameworks (Eu-MOFs) as a signal transducer and an amplifier. Eu-MOFs featuring dual emission peaks (430 nm and 620 nm) were first prepared via a facile self-assembly strategy employing Eu (III) ions and 2-aminoterephthalic acid as precursors. The high-affinity aptamer was bonded with Eu-MOFs to form Eu-MOFs@SMZ-Apt through the amidation reaction. Benefiting from the integration of inherent virtues from Eu-MOFs and aptamer, the Eu-MOFs@SMZ-Apt-based sensor allowed sensitive and selective determination of SMZ with good linear relationships in a range of 1.4-40 ng mL-1 and a low detection line (0.379 ng mL-1). This sensor was successfully applied to the determination of trace SMZ in real samples with satisfactory recoveries (86.47-113.52%) and a relative standard deviation (<6.51). Consequently, the Eu-MOFs@SMZ-Apt ratiometric fluorescence sensor furnishes new possibilities for the accurate detection of various pollutants in food.