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Multiomic insights into fungal polylactic acid degradation: Metabolic adaptation and hydrolytic mechanisms of Sporobolomyces pararoseus.

Polylactic acid (PLA), a biodegradable polyester from renewable resources, is a sustainable alternative to petrochemical plastics. However, its environmental degradation is inefficient naturally, requiring specific microbial activities. While bacterial PLA-degrading mechanisms are well documented, fungal degrading systems-particularly their molecular mechanisms-are underexplored.We isolated Sporobolomyces pararoseus ZRQ01 from the gut microbiota of PLA-fed mealworms. This fungal strain noticeably degraded PLA in PLA-containing medium supplemented with 2% glucose. Biodegradation assays revealed 22.8% loss of the PLA film weight after 35 days of incubation, and scanning electron microscopy confirmed extensive surface erosion and pore formation. Integrated transcriptomic and proteomic analyses, together with the reference genome of S. pararoseus ZRQ01, revealed that S. pararoseus ZRQ01 upregulates hydrolytic enzymes at both transcript and protein levels to cleave PLA into lactic acid. After lactic acid is transferred into S. pararoseus ZRQ01 cells by monocarboxylate transporters with increased abundance, it is assimilated by pathways of pyruvate metabolism and the TCA cycle with increased protein abundance. Intriguingly, upregulation of genes in autophagy-related and MAPK signaling pathways underscores an adaptive stress response potentially supporting cellular homeostasis and degradation-related gene expression. Our results highlight S. pararoseus ZRQ01's metabolic potential for bioremediation and offer insights into fungal bioplastic degradation pathways.

Polyesters

Biological characterization of Candida parapsilosis haploids induced by voriconazole.

OBJECTIVES: Candida parapsilosis is an important opportunistic fungal pathogen causing serious human infections in nosocomial settings. It has long been thought that C. parapsilosis has a diploid genome with a high homozygosity between chromosome homologs. METHODS: In this study, we report the discovery of C. parapsilosis haploids induced by voriconazole, a triazole with broad antifungal activity against fungal pathogens, in an experimental evolutionary assay. RESULTS: The haploid strains were able to undergo auto-diploidization under in vitro culture conditions or during systemic infection at a low frequency. Compared to the progenitor diploid strain, C. parapsilosis haploid and auto-diploid strains exhibited a reduced ability of invasive growth and biofilm formation. Global transcriptional expression analysis indicated that haploid and auto-diploid strains had a similar transcriptomic profile, which showed a remarkable difference from the progenitor diploid strain perhaps due to the loss of chromosome heterozygosity. Moreover, the haploid and diploid strains had distinct fungal burdens in different animal tissues, suggesting the haploid state could have a colonization advantage over the diploids in certain tissues such as the brain and spleen. CONCLUSIONS: The discovery of C. parapsilosis haploids not only sheds lights on the biology of this important fungal pathogen, but also provides a tool for genetic modifications for the field.

Voriconazole

Transcriptomics reveals species-specific adaptive strategies to calorie restriction in two Argopecten scallops with distinct lifespans.

Calorie restriction (CR) is a well-established non-genetic intervention for lifespan extension in multiple model organisms. Seasonal food shortage in cold and temperate seas may mimic CR, inducing in bivalves a response similar to that in vertebrates and thereby prolonging life expectancy. However, the relationship and the mechanism underlying the food availability and lifespan in bivalves remain largely unexplored. Two closely related scallop species the short-lived warm-water Argopecten irradians (lifespan <2&#xa0;years) and the longer-lived cold-water Argopecten purpuratus (7-10&#xa0;years) provide an ideal comparative system to investigate species-specific adaptive strategies. In this study, we subjected both species to CR for 30 and 56&#xa0;days and performed comparative transcriptomic profiling, weighted gene co-expression network analysis (WGCNA), and physiological assays to elucidate their distinct molecular responses. Transcriptomic analysis revealed that A. purpuratus exhibited substantially more DEGs than A. irradians at both time points under CR, with both species showing downregulation of metabolic pathways but to different extents. A. irradians mounted an early nutrient-sensing response at 30&#xa0;days (IGF1R, PIK3R3, INSR suppression), indicating acute sensitivity to limitation; by contrast, A. purpuratus displayed delayed FoxO activation at 56&#xa0;days, along with its downstream effectors NFKBIA, CREB3L4, and SMAD4, suggesting a gradual adaptive program may link to its extended lifespan. WGCNA identified three negatively correlated modules in each species, with coral2 being the most prominent in A. irradians and darkolivegreen in A. purpuratus. The former was dominated by ciliary motility genes, whereas the latter featured coordinated repression of oxidative phosphorylation. Additionally, both species exhibited conserved suppression of mTOR/S6K growth signaling and activation of cellular maintenance programs. Collectively, these findings expand the understanding of CR-mediated longevity regulation in bivalves and provide candidate gene resources for future functional studies and breeding programs.

Pectinidae

Accurate quantification of canine mitochondrial DNA copy number from canine blood and brain samples.

Acute brain injury is difficult to evaluate in veterinary medicine and tools to investigate the potential involvement of mitochondrial involvement are limited. The brain is highly enriched in mitochondria and contains thousands of copies of mitochondrial DNA (mtDNA) per cell, but robust methods for quantifying mitochondrial DNA copy number (mtDNA-CN) in canine tissues are lacking. We describe the development of a quantitative real-time PCR assay for absolute measurement of mtDNA-CN which was validated in canine blood and brain tissue. To minimize amplification of nuclear mitochondrial insertion sequences (NumtS) and repetitive regions, species-specific oligonucleotide primers were designed following in silico genomic filtering. The assay was applied to a small pilot cohort comprising blood samples from dogs with and without acute brain injury (n&#xa0;=&#xa0;4-6 per group) and cerebral cortex samples (n&#xa0;=&#xa0;1 per group) to assess feasibility and biological plausibility. In non-brain injury dogs, blood mtDNA-CN ranged from 98 to 288 copies per nuclear genome (mean 193&#xa0;&#xb1;&#xa0;72), while values in brain-injured cases ranged from 163 to 228 copies per genome (mean 200&#xa0;&#xb1;&#xa0;33). Cerebral cortex samples exhibited higher mtDNA-CN than blood, consistent with known tissue-specific mitochondrial enrichment. In a single brain-injured case with serial sampling, mtDNA-CN increased over five days. This study presents a validated assay and pilot data for mtDNA-CN quantification in canine samples. While not powered for biomarker evaluation, this method may enable future studies of mitochondrial dynamics in canine brain injury and metabolic disease.

Animals

Identification of the BrSK gene family in flowering Chinese cabbage and functional characterization of BrSK2 subfamily involvement in heat stress.

Glycogen synthase kinase 3 (GSK3) kinases are evolutionarily conserved regulators of plant development and stress signaling, yet their contributions to thermotolerance in cool-adapted Brassica crops remain poorly understood. Here, we identified 16 BrSK genes in the Caixin (Brassica rapa ssp. chinensis var. parachinensis) genome, all harboring intact catalytic motifs indicative of functional kinase activity. Spatiotemporal expression profiling revealed preferential accumulation of BrSK transcripts in stem apices and floral organs during reproductive transition, while promoter analysis identified abundant heat- and abiotic stress-responsive cis-elements. Under heat stress, BrSK21, BrSK22, and BrSK23 displayed striking genotype-specific expression dynamics. BrSK21/22/23 transcripts were stably suppressed in the heat-tolerant cultivar '49-19' but transiently declined before rapidly rebounding in the heat-sensitive 'Liuye 50', mirroring RNA-seq profiles. Protein-protein interaction assays (Y2H, BiFC, and LCI) demonstrated specific associations between BrSK kinases and BrHSFA1. Functional validation via VIGS revealed that silencing of BrSK21 significantly enhanced thermotolerance, with triple silencing of BrSK21/22/23 conferring additive protection, indicating functional redundancy within the BrSK2 subfamily. Collectively, these findings establish the BrSK2 subfamily as negative regulators of heat tolerance in Caixin, likely via modulation of BrHSFA1 expression. This work identifies high-priority targets for molecular breeding of climate-resilient Brassica vegetables.

Plant Proteins

Genome-wide identification and functional validation of asparagine synthetase genes (NtASNs) in Nicotiana tabacum.

Asparagine (Asn) is pivotal for plant nitrogen (N) metabolism and plays indispensable roles in plant growth, development, and stress tolerance. However, the systematic characteristics and core functions of asparagine synthetase genes (NtASNs) in tobacco remain unclear. Through a comprehensive genome-wide investigation, nine members of the NtASN gene family were identified. Subsequent CRISPR/Cas9-mediated knockout and overexpression assays of these NtASN genes revealed that NtASN1e, NtASN2a, and NtASN2b are the core genes responsible for Asn biosynthesis in tobacco. Their knockout reduced asparagine synthetase activity and Asn content, delayed seed germination by 2-3 days, and displayed elevated oxidative injury when exposed to salinity conditions. In contrast, overexpression of these genes elevated Asn accumulation. Subcellular localization analysis indicated that NtASN1e was localized to both the cytoplasm and chloroplasts, whereas NtASN2a exhibited dual localization in the cytoplasm and endoplasmic reticulum, and NtASN2b was mainly localized in the cytoplasm. This study systematically clarifies the evolutionary characteristics and core functions of the NtASN gene family and provides candidate genes for optimizing nitrogen metabolism and improving salt-stress adaptation in tobacco. These findings hold important practical significance for molecular breeding and product quality improvement in industrial crops.

Nicotiana

Feasibility of routine clinical liquid-based cytology for lung cancer compact panel testing.

BACKGROUND: The Lung Cancer Compact Panel (cPANEL) is a recently approved highly sensitive multiplex gene panel in Japan that supports both DNA- and RNA-based next-generation sequencing. Although cytological specimens are acceptable for cPANEL, unfixed cell pellets or dedicated preservation tubes are typically recommended. However, evidence remains limited regarding whether residual liquid-based cytology (LBC) cell suspensions prepared for routine cytological diagnosis can be used directly for cPANEL testing without dedicated molecular preservation or additional preanalytical processing. In this study, we evaluated the feasibility of applying LBC specimens that are widely used in contemporary clinical practice to cPANEL. METHODS: We analyzed DNA and RNA quality in 69 clinical LBC specimens. Among these, 51 specimens containing non-small cell lung cancer cells with previously determined driver alteration status were subjected to cPANEL testing to evaluate assay concordance with clinical companion diagnostic results. RESULTS: DNA integrity was generally well preserved (DNA Integrity Number [DIN]: 6.2&#xa0;&#xb1;&#xa0;1.5). In contrast, RNA integrity showed greater variability (DV200: 16.4&#xa0;&#xb1;&#xa0;12.1%). ThinPrep-fixed specimens demonstrated lower DIN and DV200 values compared with CytoRich Red-fixed specimens. Although all samples successfully passed the DNA-based cPANEL assay, six cases (11.8%) failed the RNA-based assay, with RNA yield being a major contributing factor. Among the 46 evaluable specimens, concordance was 95.7% and sensitivity was 92.3%, or 88.9% including RNA module failures as cPANEL-negative. CONCLUSIONS: With appropriate fixative selection and adequate cellularity, cPANEL using clinical LBC specimens may serve as a practical diagnostic platform. We demonstrated that routine LBC specimens can be directly applied to cPANEL without special preanalytical processing.

Humans

Optimizing eco-engineering pedogenesis of bauxite residues: Synergistic effects of humus and FeSO4/sulfur on microbial community and function.

Eco-engineered pedogenesis represents a promising approach for soil amelioration of bauxite residues (BRs) through exogenous organic matter. However, the role of humus in mediating this process remains poorly understood, significantly impeding the eco-engineering rehabilitation of BRs. In this study, we conducted pot experiments and subsequent microbial analysis to evaluate the individual improvement of humic acid (HA), fulvic acid (FA), and corn straw (SWZ) on the BRs' pedogenesis. High-throughput sequencing analysis revealed that both FA and SWZ were more effective than HA in steering microbial community assembly, as community diversity, dominant taxa enrichment, and species' interaction were all significantly higher (p < 0.05) in the FA/SWZ treatments than in HA treatments. Notably, the combination of FA with FeSO4 specifically enriched halophilic taxa, while FA coupled with sulfur (S) significantly improved the connectivity and complexity of the microbial network, as the average connection degree increasing from 1.008 to 1.113. Hydrolytic enzyme activity assays further indicated that FA, especially when combined with S, was the most effective treatment in restoring microbial function during BR pedogenesis. These findings highlight FA as a critical driver of microbial restructuring and functional recovery in BRs. Moreover, its efficacy can be enhanced by co-amendment with FeSO4 or S. This study provides important theoretical and practical insights for optimizing organic-inorganic amendment strategies to accelerate the eco-engineering pedogenesis of bauxite residues.

Humic Substances

An Update on Inborn Errors of V(D)J Recombination.

V(D)J recombination is the fundamental process by which developing T and B lymphocytes generate diverse antigen receptors, enabling adaptive immunity. This tightly regulated program operates exclusively in lymphoid precursors during G1 phase and depends on the lymphocyte-specific RAG1-RAG2 recombinase to introduce programmed DNA double-strand breaks at recombination signal sequences, followed by repair through the classical nonhomologous end joining (c-NHEJ) pathway. Disruption of any step in this molecular choreography compromises antigen receptor diversity and underlies a spectrum of inborn errors of immunity (IEIs), ranging from severe combined immunodeficiency (SCID) to immune dysregulation with autoimmunity and granulomatous disease. In this review, we place disorders of V(D)J recombination within the broader framework of T-cell development, detailing the temporal waves of recombinase activity, chromatin accessibility, and DNA damage responses that guide thymocyte differentiation. We discuss pathogenic variants affecting the cleavage phase [RAG1, RAG2, and the recently identified RAG cochaperone NudC domain-containing 3 (NUDCD3)], end processing (ARTEMIS), ligation and repair (LIG4, XLF, XRCC4, PRKDC), and genome surveillance pathways (ATM, MRN complex, RNF168), highlighting genotype-phenotype correlations and mechanisms driving immune deficiency and dysregulation. We briefly review recent diagnostic advances, including newborn screening using T-cell receptor excision circles, repertoire sequencing, and functional assays, alongside current therapeutic strategies. Finally, we outline key unanswered questions and argue that continued integration of clinical observation with molecular discovery is essential to improve outcomes and deepen understanding of adaptive immune development.

Humans

From bioactive compounds to volatile profiles: a multidimensional characterization of Indonesian stingless bee honeys.

BACKGROUND: Stingless bee honeys are drawing increasing attention as ingredients for functional foods and health-oriented products because of their distinctive sensory characteristics and bioactive potential. In this study, honeys collected from nine stingless bee species reared in West Sumatra, Indonesia, were comprehensively characterized using physicochemical indices, antioxidant assays [DPPH (i.e. 2,2-diphenyl-1-picrylhydrazyl) and ferric reducing antioxidant power], microbiological screening, volatile profiling [gas chromatography-mass spectrometry (GC-MS)] and Fourier transform infrared (FTIR) fingerprinting. RESULTS: Marked between-sample variability was observed across key quality attributes, including pH (2.80-3.68), Brix (49.83-61.25), viscosity (23.36-175.22&#x2009;cP) and color parameters. FTIR spectra were consistent with carbohydrate-rich matrices and exhibited carbonyl-related bands. GC-MS profiling identified linalool oxide isomers and junenol among the predominant volatiles. To the best of our knowledge, junenol has not previously been reported in stingless bee honey and may represent a potential regional chemical marker for Indonesian stingless bee honeys. Lactic acid bacteria were detected in selected samples, whereas yeast and mold were not detected. Antioxidant activities were comparatively low, which may reflect local environmental and ecosystem-related factors. CONCLUSION: The results provide a multi-parameter baseline for stingless bee honeys produced within a shared ecosystem in West Sumatra and demonstrate the value of integrating conventional chemical indices with FTIR and volatile fingerprints for quality assessment. This combined approach may also support future authentication and origin-tracing frameworks for Indonesian stingless bee honeys. &#xa9; 2026 Society of Chemical Industry.

Animals

Advances in cereal protein applications for infant and Young child nutrition.

BACKGROUND: The increasing use of plant-derived proteins in infant and young child nutrition necessitates tailored amino acid profiles, high digestibility and strict safety controls. Cereal proteins, such as rice, oat, maize, millet, barley, and wheat, are widely used in complementary foods but face intrinsic limitations, notably lysine and tryptophan deficits, antinutritional factors that reduce bioavailability, gluten immunogenicity in wheat/barley, and inorganic arsenic risks in rice. SCOPE AND APPROACH: This review synthesizes recent advances in processing and formulation strategies, including enzymatic hydrolysis, fermentation, germination, extrusion, cereal-legume complementation, and micronutrient fortification. Their impacts on digestibility, techno-functionality, iron and zinc bioavailability, and protein quality, including Protein Digestibility-Corrected Amino Acid Score (PDCAAS) and Digestible Indispensable Amino Acid Score (DIAAS) are critically reviewed using data from in vitro assays, product development, and clinical trials. KEY FINDINGS AND CONCLUSIONS: Processing and blending approaches can substantially improve protein digestibility, amino acid balance and micronutrient availability, and hydrolyzed rice protein holds clinical promise for cow's milk protein allergy (CMPA). However, most evidence is preclinical, reporting of protein quality is inconsistent, and industrial translation is constrained by sensory, shelf-life, contaminant and cost issues. We recommend standardized DIAAS-based reporting, large-scale feeding trials, sensory /stability optimization, and targeted exploration of underutilized grains (e.g., oat, millet) with active allergen monitoring. Prioritizing amino acid-focused formulation coupled with strategies to enhance micronutrient bioavailability will accelerate safe adoption of cereal proteins in early-life nutrition.

Humans

In vitro EVALUATION OF Beauveria bassiana ISOLATES AGAINST GASTROINTESTINAL NEMATODES FROM GOATS.

Biological control has emerged as a promising alternative for the control of gastrointestinal nematodes in small ruminants. However, additional information is still needed on the nematicidal portencial of Beauveria bassiana and on the early interaction between fungal conidia and infective larvae. In this study, six B. bassiana isolates (LCMS19-LCMS24) were evaluated in vitro using a coproculture assay with fecal samples from naturally infected goats. Larval recovery was compared with that of an untreated control to estimate the percentage reduction in third-stage larvae (L3). The most effective isolate was subsequently examined by scanning electron microscopy (SEM) to characterize its interaction with L3. All isolates reduced L3 recovery compared with the control, although their efficacy differed. LCMS21 showed the greatest reduction in L3 recovery and differed significantly from the other treatments. SEM revealed extensive adhesion of LCMS21 conidia to the L3 cuticle, in the anterior and median regions. However, no clear evidence of conidial germination, germ tube formation, cuticle penetration, or hyphal development was observed after 48 or 72 h. These results indicate that B. bassiana isolates differ in their in vitro activity against gastrointestinal nematodes and identify LCMS21 as the most promising isolate among those tested. The ultrastructural observations support an early fungus-larva interaction, but they do not allow the nematicidal effect to be attributed to adhesion. Further studies are needed to clarify the mechanisms involved and to evaluate the potencial application of this isolate in integrated parasite control programs.

Beauveria bassiana

A horizontally acquired gene mediates insect cocoon pigmentation in the eri silkmoth, Samia ricini.

Holometabolous insects make cocoons during larval-pupal metamorphosis to protect the pupal phase. The materials used for cocoon construction vary widely. Lepidopteran insects typically secrete silk to form cocoons, which display diverse colors. The eri silkworm, Samia cynthia ricini, is an economically important domesticated species that mostly produces white cocoons, with some varieties producing red cocoons. The enzyme kynureninase (KYNU), acquired from bacteria by horizontal gene transfer, has previously been implicated in insect coloration, while the tryptophan metabolite 3-hydroxyanthranilic acid (3-HAA) has been identified as a red pigment. However, exactly how KYNU is involved in cocoon pigmentation remains unclear. Here, we report that a horizontally transferred bacterial gene encoding KYNU regulates red cocoon formation. Metabolomic analysis revealed a high accumulation of 3-HAA in red cocoons, confirming its role as the primary pigment and associating the coloration with tryptophan metabolism. Quantitative real-time polymerase chain reaction (qPCR) analysis indicated that SrKYNU is highly expressed in the silk glands and significantly downregulated in the red cocoon strain compared to the white cocoon strain. Genomic sequencing identified a 141 bp deletion in the upstream regulatory region of KYNU in the red cocoon strain compared to the white cocoon strain. Dual-luciferase assays confirmed that this deletion significantly reduced promoter activity. CRISPR/Cas9 knockout of SrKYNU in the white-cocoon strain resulted in mutants producing red cocoons with elevated 3-HAA content. These findings reveal that the horizontally transferred gene SrKYNU exhibits tissue-specific expression and regulates cocoon coloration in S. ricini, illustrating that horizontal gene transfer can play an important role in regulating an insect physiological process.

Animals

Alternative End Joining Dependency Imposed by miR-21-5p Defines Radiation Resistance and a Targetable Vulnerability in Oral Squamous Cell Carcinoma.

PURPOSE: Clinical control of oral squamous cell carcinoma (OSCC) is constrained by heterogeneous radiosensitivity driven by divergent DNA damage response programs. The architecture and functional contribution of alternative end joining (Alt-EJ), an error-prone DNA double-strand break (DSB) repair pathway frequently upregulated in cancer, to radiation resistance remains poorly defined. METHODS AND MATERIALS: We profiled microRNAs in radioresistant OSCC clones and performed multiomic integration across an institutional OSCC cohort, an external OSCC cohort from the Gene Expression Omnibus, The Cancer Genome Atlas pan-cancer tumors, and cell lines characterized by Sanger Genomics of Drug Sensitivity in Cancer to infer DNA damage response characteristics, genomic scar features, drug sensitivity, and radiation therapy outcomes. DSB repair capacity and pathway usage were validated using functional assays, including Alt-EJ reporters and droplet digital PCR quantification of microhomology-mediated repair events. Core Alt-EJ effectors such as PARP1 and POLQ were perturbed genetically and pharmacologically. Therapeutic efficacy of PARP or POLQ inhibition with or without irradiation was tested in a syngeneic OSCC model, followed by bulk tumor transcriptomics to assess pathway engagement. RESULTS: Upregulation of miR-21-5p was not only selectively detected in radioresistant OSCC, but also modulated radiosensitivity in vitro and in vivo, and was associated with inferior postradiation therapy survival. A calibrated miR-21-5p target-gene signature tracked Alt-EJ activity across patient and mouse tumors and cancer cell lines, correlated with microhomology-mediated indels and broader genomic scarring, and predicted sensitivity to clinically available PARP inhibitors. Functionally, enforced miR-21-5p expression increased Alt-EJ usage and accelerated DSB repair, whereas inhibition or depletion of key Alt-EJ effectors reduced repair efficiency and restored radiosensitivity. In vivo, Alt-EJ targeting with PARP or POLQ inhibitor abrogated miR-21-5p-driven radiation resistance; transcriptomic profiling supported suppression of Alt-EJ programs as the operative mechanism. CONCLUSIONS: These findings establish a mechanistic link between miR-21-5p activity and Alt-EJ dependence, provide a clinically deployable signature to identify Alt-EJ-dependent OSCC, and support rational combinations of Alt-EJ targeting agents with radiation therapy to overcome treatment failure and advance precision radiation oncology.

MicroRNAs

Functional characterization of the MdFLZ2 gene in drought and salt stress tolerance in apple.

Drought and salt stress are significant environmental limitations that severely constrain plant growth and productivity, therefore, enhancing stress tolerance is a key goal in crop improvement. The plant-specific FCS-like zinc finger (FLZ) proteins have been identified as important regulators of stress adaptation. In this study, we conducted a genome-wide characterization of the FLZ gene family in apple and functionally characterized MdFLZ2. qRT-PCR analysis revealed that MdFLZ2 was differentially expressed across various tissues and transcriptionally induced by both drought and salt stress. Subcellular localization assays demonstrated that the MdFLZ2 protein is localized to both the nucleus and the cytoplasm. The overexpression of MdFLZ2 in apple calli, Arabidopsis and tomato conferred increased resistance to drought and salt stress. In addition, yeast two-hybrid (Y2H) assays confirmed that MdFLZ2 interacted with MdSnRK1.1, and similar interactions were also detected between other MdFLZ family members and MdSnRK1.1. Collectively, our findings suggest MdFLZ2 as a positive regulator of drought and salt tolerance and highlight its potential to serve as a genetic resource for abiotic stress improvement.

Malus

Effects of umbilical cord mesenchymal stem cell-derived exosomes on periodontal ligament stem cells: An exploratory study.

OBJECTIVE: To investigate whether exosomes derived from human umbilical cord mesenchymal stem cells (UCMSCs) at two osteogenic induction stages (undifferentiated and late-stage) differentially affect periodontal ligament stem cells (PDLSCs), and to explore the potential molecular basis. DESIGN: UCMSCs and PDLSCs were isolated and cultured. Exosomes were harvested from undifferentiated UCMSCs (Exo-D0) and UCMSCs after 14 days of osteogenic induction (Exo-D14). PDLSCs were treated with both exosome types. Proliferation and migration were analyzed using EdU and scratch assays, the latter under serum-free conditions. Early osteogenic differentiation was assessed by alkaline phosphatase staining and quantitative reverse transcription PCR (qRT-PCR). Differentially expressed miRNAs were identified by high-throughput sequencing and further analyzed through Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses. RESULTS: Both exosome types promoted PDLSC migration. Exo-D0 enhanced early osteogenic differentiation, whereas Exo-D14 enhanced proliferation but reduced early osteogenic marker expression. Sequencing identified 21 differentially expressed miRNAs (13 upregulated, 8 downregulated). Bioinformatic prediction suggested that the putative target genes were enriched in Ras signal transduction, regulation of kinase activity, and focal adhesion, and further predicted significant enrichment in the MAPK, Ras, and PI3K-Akt signaling pathways, which are central to cell proliferation and osteogenic differentiation. CONCLUSIONS: Exosomes from undifferentiated and osteogenically induced UCMSCs exerted distinct effects on PDLSCs, potentially associated with differentially packaged miRNAs. These findings offer a basis for hypotheses about exosome-mediated mechanisms and support matching exosome sources to the intended therapeutic outcome as potential cell-free strategies for periodontal tissue regeneration and alveolar bone repair.

Humans

Antagonistic regulation by mango MiSPL9a and MiSPL9b regulates flowering time, drought and salt stress in Arabidopsis.

SQUAMOSA PROMOTER BINDING PROTEIN-LIKE (SPL) transcription factors, which are unique to plants, contain a highly conserved SBP domain that regulates gene expression by binding to downstream targets. They play critical roles in various biological processes, especially in the regulation of flowering in plants. In this study, two SPL-like genes (MiSPL9a and MiSPL9b) were identified from mango genomic and transcriptomic data, and their sequence, expression and function were further analyzed. Sequence analysis revealed that MiSPL9a and MiSPL9b have open reading frames of 1173&#xa0;bp and 1158&#xa0;bp, respectively, with slight differences in the number of cis-regulatory elements within their promoter regions. Expression analysis under stress conditions revealed distinct patterns: MiSPL9a expression significantly differed under drought stress but did not significantly differ under salt stress, whereas MiSPL9b expression responded significantly to salt stress but changed minimally under drought stress. Phenotypic analysis of the transgenic Arabidopsis lines revealed that MiSPL9a overexpression delayed flowering, whereas MiSPL9b overexpression promoted early flowering. Under stress conditions, compared with wild-type plants, MiSPL9a-overexpressing plants presented increased drought tolerance but did not significantly differ. In contrast, MiSPL9b-overexpressing plants were sensitive to salt stress, with no notable phenotypic differences observed under drought conditions. Physiological assays revealed that under drought stress, MiSPL9a transgenic plants presented significantly reduced levels of malondialdehyde (MDA) and hydrogen peroxide (H2O2) and increased proline (Pro) content and superoxide dismutase (SOD) activity. Under salt stress, MiSPL9b transgenic plants presented opposite trends in terms of these physiological markers. In summary, both MiSPL9a and MiSPL9b are involved in the regulation of plant flowering time and stress responses, but their functions differ.

Arabidopsis

A homogeneous immunoassay based on AlphaLICA technology for detecting florfenicol residues in animal-derived foods.

Florfenicol (FF), a broad-spectrum amide antibiotic widely used in livestock, poultry, and aquaculture, poses potential threats to food safety and public health due to its residual accumulation. In this study, a novel homogeneous immunoassay based on Amplified Luminescent Proximity Homogeneous Assay (AlphaLICA) technology was developed for the first time for rapid screening of FF residues in milk and egg matrices. By covalently immobilizing the FF-BSA conjugate and goat anti-mouse IgG onto luminescent and photosensitive microspheres, respectively, the method achieved wash-free, homogeneous quantitative detection through a competitive immunoreaction. Under optimized conditions, the assay exhibited a linear range of 0.2-16.2 ng mL-1, with a limit of detection of 9.7 pg mL-1 and a limit of quantification of 183 pg mL-1. The intra- and inter-batch coefficients of variation ranged from 3.08% to 5.70% and 2.44% to 7.09%, respectively. Spike recovery rates in milk and egg matrices ranged from 93.18% to 107.17% (RSD &#x2264; 5.57%). Cross-reactivity with 11 other common antibiotics, including chloramphenicol and thiamphenicol, was below 0.1%, demonstrating excellent specificity. Comparative analysis with a commercial ELISA kit showed high consistency (r2 = 0.9332, p < 0.001). With high sensitivity, strong specificity, simple operation, and a detection time of only 10 min, this method provides a reliable technical platform for high-throughput, rapid monitoring of FF residues in milk and egg matrices.

Journal Article