Designing Degradable Polymers from Tricycloalkenes via Complete Cascade Metathesis Polymerization.

Cascade metathesis polymerization has been developed as a promising method to synthesize complex but well-defined polymers from monomers containing multiple reactive functional groups. However, this approach has been limited to the monomers involving simple alkene/alkyne moieties or produced mainly non-degradable polymers. In this study, we demonstrate a complete cascade ring-opening/ring-closing metathesis polymerization (RORCMP) using various tricycloalkenes and two strategies for the efficient degradation. Through rational design of tricycloalkene monomers, the structure and reactivity relationship was explored. For example, tricycloalkenes with trans configuration in the central ring enabled faster and better selective cascade RORCMP than the corresponding cis isomers. Also, a 4-substituted cyclopentene moiety in the monomers significantly enhanced the overall cascade RORCMP performance, with the maximum turnover number (TON) reaching almost 10,000 and molecular weight up to 170 kg/mol using an amide-containing monomer. Furthermore, we achieved one-shot cascade multiple olefin metathesis polymerization using tricycloalkenes and a diacrylate, to produce new highly A,B-alternating copolymers with full degradability. Lastly, we successfully designed xylose-based tricycloalkenes to give well-defined polymers that underwent ultra-fast and complete degradation under mild conditions.

Hypoxia-inducible factor 1 recruits FACT and RNF20/40 to mediate histone ubiquitination and transcriptional activation of target genes.

Hypoxia-inducible factor 1 (HIF-1) is a transcriptional activator that mediates cellular adaptation to decreased oxygen availability. HIF-1 recruits chromatin-modifying enzymes leading to changes in histone acetylation, citrullination, and methylation at target genes. Here, we demonstrate that hypoxia-inducible gene expression in estrogen receptor (ER)-positive MCF7 and ER-negative SUM159 human breast cancer cells requires the histone H2A/H2B chaperone facilitates chromatin transcription (FACT) and the H2B ubiquitin ligase RING finger protein 20/40 (RNF20/40). Knockdown of FACT or RNF20/40 expression leads to decreased transcription initiation and elongation at HIF-1 target genes. Mechanistically, FACT and RNF20/40 are recruited to hypoxia response elements (HREs) by HIF-1 and stabilize binding of HIF-1 (and each other) at HREs. Hypoxia induces the monoubiquitination of histone H2B at lysine 120 at HIF-1 target genes in an HIF-1-dependent manner. Together, these findings delineate a cooperative molecular mechanism by which FACT and RNF20/40 stabilize multiprotein complex formation at HREs and mediate histone ubiquitination to facilitate HIF-1 transcriptional activity.

Intestinal metabolite UroB alleviates cerebral ischemia/reperfusion injury by promoting competition between TRIM65 and TXNIP for binding to NLRP3 inflammasome in response to neuroinflammation.

Our previous research suggests that targeting NLRP3 inflammasomes holds promise for mitigating cerebral ischemia/reperfusion injury. The gut metabolite Urolithin B (UroB) has been shown to inhibit the neuroinflammation. However, the specific role of UroB in cerebral ischemia/reperfusion injury and its potential impact on NLRP3 inflammasome remain unclear. In this study, acute stroke was simulated using the MCAO model in male Sprague-Dawley rats. UroB was intraperitoneally administered after 1 h of reperfusion. The effects of UroB on brain tissue were evaluated, including infarct volume, brain edema, and neurobehavioral changes. Western blotting and immunofluorescence were performed to investigate the effect of UroB on inflammation-related proteins. Furthermore, TRIM65 knockdown and TXNIP overexpression experiments elucidated the role of UroB in NLRP3 inflammasome activation. The ( demonstrate the neuroprotective effect of UroB in acute stroke, reducing brain tissue damage and improving motor function. Mechanistically, UroB modulated neuroinflammation by influencing TXNIP and TRIM65 protein expression, as well as competitive binding to the NLRP3 inflammasome, attenuating cerebral ischemia/reperfusion injury. In conclusion, the potential of UroB as a protective agent against cerebral ischemia/reperfusion injury in acute stroke stands out as it regulates TRIM65 and TXNIP competitive binding to the NLRP3 inflammasome. These findings suggest that UroB is a promising drug candidate for the treatment of acute stroke.

Bimodal DNA self-origami material with nucleic acid function enhancement.

BACKGROUND: The design of DNA materials with specific nanostructures for biomedical tissue engineering applications remains a challenge. High-dimensional DNA nanomaterials are difficult to prepare and are unstable; moreover, their synthesis relies on heavy metal ions. Herein, we developed a bimodal DNA self-origami material with good biocompatibility and differing functions using a simple synthesis method. We simulated and characterized this material using a combination of oxDNA, freeze-fracture electron microscopy, and atomic force microscopy. Subsequently, we optimized the synthesis procedure to fix the morphology of this material. RESULTS: Using molecular dynamics simulation, we found that the bimodal DNA self-origami material exhibited properties of spontaneous stretching and curling and could be fixed in a single morphology via synthesis control. The application of different functional nucleic acids enabled the achievement of various biological functions, and the performance of functional nucleic acids was significantly enhanced in the material. Consequently, leveraging the various functional nucleic acids enhanced by this material will facilitate the attainment of diverse biological functions. CONCLUSION: The developed design can comprehensively reveal the morphology and dynamics of DNA materials. We thus report a novel strategy for the construction of high-dimensional DNA materials and the application of functional nucleic acid-enhancing materials.

Combination of a human articular cartilage-derived extracellular matrix scaffold and microfracture techniques for cartilage regeneration: A proof of concept in a sheep model.

Background: The utilization of decellularized extracellular matrix has gained considerable attention across numerous areas in regenerative research. Of particular interest is the human articular cartilage-derived extracellular matrix (hACECM), which presents as a promising facilitator for cartilage regeneration. Concurrently, the microfracture (MF) â€‹technique, a well-established marrow stimulation method, has proven efficacious in the repair of cartilage defects. However, as of the current literature review, no investigations have explored the potential of a combined application of hACECM and the microfracture technique in the repair of cartilage defects within a sheep model. Hypothesis: The combination of hACECM scaffold and microfracture will result in improved repair of full-thickness femoral condyle articular cartilage defects compared to the use of either technique alone. Study design: Controlled laboratory study. Methods: Full-thickness femoral condyle articular cartilage defect (diameter, 7.0 â€‹mm; debrided down to the subchondral bone plate) were created in the weight-bearing area of the femoral medial and lateral condyles (n â€‹= â€‹24). All of defected sheep were randomly divided into four groups: control, microfracture, hACECM scaffold, and hACECM scaffold â€‹+ â€‹microfracture. After 3, 6 and 12 months, the chondral repair was assessed for standardized (semi-) quantitative macroscopic, imaging, histological, immunohistochemical, mechanics, and biochemical analyses in each group. Result: At 3, 6 and 12 months after implantation, the gross view and pathological staining of regenerative tissues were better in the hACECM scaffold and hACECM scaffold â€‹+ â€‹microfracture groups than in the microfracture and control groups; Micro-CT result showed that the parameters about the calcified layer of cartilage and subchondral bone were better in the hACECM scaffold and hACECM scaffold â€‹+ â€‹microfracture groups than the others, and excessive subchondral bone proliferation in the microfracture group. The results demonstrate that human cartilage extracellular matrix scaffold alone is an efficient, safe and simple way to repair cartilage defects. Conclusion: hACECM scaffolds combined with/without microfracture facilitate chondral defect repair. The translational potential of this article: Preclinical large animal models represent an important adjunct and surrogate for studies on articular cartilage repair, while the sheep stifle joint reflects many key features of the human knee and are therefore optimal experimental model for future clinical application in human. In this study, we developed a human articular cartilage-derived extracellular matrix scaffold and to verify the viability of its use in sheep animal models. Clinical studies are warranted to further quantify the effects of hACECM scaffolds in similar settings.

Experience of rehabilitation specialist nurses in providing bowel care for stroke patients: A qualitative study.

AIMS: This study aims to explore the experiences of rehabilitation specialist nurses in providing bowel care to stroke patients and to identify the factors that either facilitate or hinder their practice. DESIGN: This was a descriptive qualitative design study. METHODS: Between May 2022 and October 2022, we conducted in-depth and semi-structured interviews with 12 rehabilitation specialist nurses from two tertiary hospitals in Changsha, China. Thematic analysis was employed to analyse the interview transcripts. FINDINGS: Three key themes were revealed from our analysis: (1) acceptance of bowel care as a process, (2) high level of recognition improves the experience and (3) challenges stemming from limited knowledge and rights. Acceptance of bowel care as a dynamic process, coupled with a high level of recognition, enabled nurses to prioritize the health and safety of patients over personal feelings and achieve professional accomplishments. However, they encountered challenges in terms of professional development and restricted prescribing rights for bowel care. CONCLUSION: The experiences of rehabilitation specialist nurses in providing bowel care are dynamic. These findings have important implications for healthcare improvement, including the need for collaboration with healthcare professionals and nurturing nurses' self-identity, comprehensive training plans, innovative programs and expanding the scope of rehabilitation specialist nurses' rights. IMPACT: This study enhances our understanding of the challenges faced by rehabilitation specialist nurses caring for stroke patients with neurogenic bowel dysfunction. The findings provide insights into how to enhance bowel care experience and develop further in this field. REPORTING METHOD: This study adhered to the EQUATOR guideline and utilized the COREQ checklist. PATIENT OR PUBLIC CONTRIBUTIONS: This study involved participants who were registered nurses, and there were no contributions from patients or public.

Causal associations of thyroid function and sudden sensorineural hearing loss: a bidirectional and multivariable Mendelian randomization study.

Background: Observational studies have indicated a potential association between thyroid dysfunction and the risk of sudden sensorineural hearing loss (SSNHL). However, the precise causal relationship between the two remains uncertain. The objective of our study was to assess the causal influence of thyroid function on SSNHL by employing a bidirectional and multivariable Mendelian randomization (MR) approach. Methods: Single-nucleotide polymorphisms (SNPs) associated with free thyroid (FT4) and thyroid stimulating hormone (TSH) were selected from the summary data of a large genome-wide association study (GWAS) conducted on European individuals. The summary-level data of SSNHL were also obtained from a GWAS, which included 196,592 participants (1,491 cases and 195,101 controls). The MR analysis primarily utilized the inverse variance weighted (IVW) method, with sensitivity analyses performed using the weighted median, MR-Egger, and MR-PRESSO approaches. Results: In the IVW method, an elevated genetically predicted FT4 level was found to effectively reduce the risk of SSNHL (OR = 0.747, 95% CI = 0.565-0.987, P = 0.04). These findings were consistent when conducting multivariate MR analysis, which adjusted for TSH levels (OR = 0.929, 95% CI = 0.867-0.995, P = 0.036). However, genetically predicted TSH levels did not emerge as a risk factor for SSNHL (OR = 1.409, 95% CI = 0.895-1.230, P = 0.547). Furthermore, even after adjusting for FT4 levels in the multivariate MR analysis, no evidence of a direct causal relationship between TSH levels and the risk of SSNHL was observed (OR = 1.011, 95% CI = 0.880-1.161, P = 0.867). The reverse MR analysis showed that there was no evidence of a direct causal relationship between SSNHL and the risk of FT4 level (OR = 1.026, 95% CI = 0.999-1.054, P = 0.056) or TSH level (OR = 1.002, 95% CI = 0.989-1.015, P = 0.702). Conclusion: Within the normal range, genetic variants associated with higher FT4 levels demonstrate a potential protective effect against SSNHL, whereas there is no direct causal relationship between TSH levels and the risk of SSNHL.

Decreased serum soluble programmed cell death ligand-1 level as a potential biomarker for missed miscarriage.

STUDY QUESTION: Can maternal serum levels of soluble programmed cell death-1 (sPD-1) and its ligand (sPD-L1) serve as biomarkers for missed miscarriage (MM)? SUMMARY ANSWER: Serum sPD-L1 levels are significantly decreased in MM patients and may serve as a potential predictive biomarker for miscarriage. WHAT IS KNOWN ALREADY: Programmed cell death-1 (PD-1) and its ligand (PD-L1) comprise important immune inhibitory checkpoint signaling to maintain pregnancy. Their soluble forms are detectable in human circulation and are associated with immunosuppression. STUDY DESIGN, SIZE, DURATION: Three independent cohorts attending tertiary referral hospitals were studied. The first (discovery) cohort was cross-sectional and included MM patients and healthy pregnant (HP) women matched on BMI. The second validation cohort contained MM patients and women with legally induced abortion (IA). The third prospective observational study recruited subjects requiring IVF treatment. PARTICIPANTS/MATERIALS, SETTING, METHODS: In the discovery cohort, we enrolled 108 MM patients and 115 HP women who had a full-term pregnancy at 6-14 weeks of gestation. In the validation cohort, we recruited 25 MM patients and 25 women with IA. Blood samples were collected at the first prenatal visit for HP women or on the day of dilatation and curettage surgery (D&C) for MM and IA subjects to determine serum sPD-1 and sPD-L1 levels. Placenta samples were harvested during the D&C within the validation cohort to measure gene and protein expression. The prospective cohort collected serial blood samples weekly from 75 volunteers with embryo transfer (ET) after IVF. MAIN RESULTS AND THE ROLE OF CHANCE: Circulating sPD-L1 levels were reduced by 50% in patients with MM (55.7 ± 16.04 pg/ml) compared to HP controls (106.7 ± 58.46 pg/ml, P < 0.001) and the difference remained significant after adjusting for maternal age and gestational age, whereas no significant differences in sPD-1 level were observed. Likewise, serum sPD-L1 was lower in MM patients than in IA subjects and accompanied by downregulated PD-L1-related gene expression levels in the placenta. In the IVF cohort, applying the changing rate of sPD-L1 level after ET achieved a predictive performance for miscarriage with receiver operating characteristics = 0.73 (95% CI: 0.57-0.88, P < 0.01). LIMITATIONS, REASONS FOR CAUTION: The study was mainly confined to East Asian pregnant women. Further large prospective pregnancy cohorts are required to validate the predictive performance of sPD-L1 on miscarriage. WIDER IMPLICATIONS OF THE FINDINGS: Reduced circulating sPD-L1 level and downregulated placental PD-L1 expression in miscarriage indicate that dysfunction in PD-L1 signals is a potential underlying mechanism for pregnancy loss. Our findings further extend the importance of the PD-L1 axis in pregnancy maintenance in early pregnancy. STUDY FUNDING/COMPETING INTEREST(S): This study was financially supported by grants from the Subject Innovation Team of Shaanxi University of Chinese Medicine (2019-Y502), General Research Fund (14122021), and Key Laboratory of Model Animal Phenotyping and Basic Research in Metabolic Diseases (2018KSYS003). The authors declare that they have no competing interests to be disclosed. TRIAL REGISTRATION NUMBER: N/A.

Enhanced Mechanical Properties of Al2O3 Nanoceramics via Low Temperature Spark Plasma Sintering of Amorphous Powders.

In this work, Al2O3 nanoceramics were prepared by spark plasma sintering of amorphous powders and polycrystalline powders with similar particle sizes. Effective comparisons of sintering processes and ultimate products depending on starting powder conditions were explored. To ensure near-full density higher than 98% of the Al2O3 nanoceramics, the threshold temperature in SPS is 1450 °C for polycrystalline Al2O3 powders and 1300 °C for amorphous powders. The low SPS temperature for amorphous powders is attributed to the metastable state with high free energy of amorphous powders. The Al2O3 nanoceramics prepared by amorphous powders display a mean grain size of 170 nm, and superior mechanical properties, including high bending strength of 870 MPa, Vickers hardness of 20.5 GPa and fracture toughness of 4.3 MPa∙m1/2. Furthermore, the Al2O3 nanoceramics prepared by amorphous powders showed a larger dynamic strength and dynamic strain. The toughening mechanism with predominant transgranular fracture is explained based on the separation of quasi-boundaries.

Low-Dose Staphylococcal Enterotoxin C2 Mutant Maintains Bone Homeostasis via Regulating Crosstalk between Bone Formation and Host T-Cell Effector Immunity.

Studies in recent years have highlighted an elaborate crosstalk between T cells and bone cells, suggesting that T cells may be alternative therapeutic targets for the maintenance of bone homeostasis. Here, it is reported that systemic administration of low-dose staphylococcal enterotoxin C2 (SEC2) 2M-118, a form of mutant superantigen, dramatically alleviates ovariectomy (OVX)-induced bone loss via modulating T cells. Specially, SEC2 2M-118 treatment increases trabecular bone mass significantly via promoting bone formation in OVX mice. These beneficial effects are largely diminished in T-cell-deficient nude mice and can be rescued by T-cell reconstruction. Neutralizing assays determine interferon gamma (IFN-γ) as the key factor that mediates the beneficial effects of SEC2 2M-118 on bone. Mechanistic studies demonstrate that IFN-γ stimulates Janus kinase/signal transducer and activator of transcription (JAK-STAT) signaling, leading to enhanced production of nitric oxide, which further activates p38 mitogen-activated protein kinase (MAPK) and Runt-related transcription factor 2 (Runx2) signaling and promotes osteogenic differentiation. IFN-γ also directly inhibits osteoclast differentiation, but this effect is counteracted by proabsorptive factors tumor necrosis factor alpha (TNF-α) and interleukin 1 beta (IL-1ß) secreted from IFN-γ-stimulated macrophages. Taken together, this work provides clues for developing innovative approaches which target T cells for the prevention and treatment of osteoporosis.

Arthritic Microenvironment-Dictated Fate Decisions for Stem Cells in Cartilage Repair.

The microenvironment and stem cell fate guidance of post-traumatic articular cartilage regeneration is primarily the focus of cartilage tissue engineering. In articular cartilage, stem cells are characterized by overlapping lineages and uneven effectiveness. Within the first 12 weeks after trauma, the articular inflammatory microenvironment (AIME) plays a decisive role in determining the fate of stem cells and cartilage. The development of fibrocartilage and osteophyte hyperplasia is an adverse outcome of chronic inflammation, which results from an imbalance in the AIME during the cartilage tissue repair process. In this review, the sources for the different types of stem cells and their fate are summarized. The main pathophysiological events that occur within the AIME as well as their protagonists are also discussed. Additionally, regulatory strategies that may guide the fate of stem cells within the AIME are proposed. Finally, strategies that provide insight into AIME pathophysiology are discussed and the design of new materials that match the post-traumatic progress of AIME pathophysiology in a spatial and temporal manner is guided. Thus, by regulating an appropriately modified inflammatory microenvironment, efficient stem cell-mediated tissue repair may be achieved.

Plexin-B3 expression stimulates MET signaling, breast cancer stem cell specification, and lung metastasis.

Intratumoral hypoxia is a microenvironmental feature that promotes breast cancer progression and is associated with cancer mortality. Plexin B3 (PLXNB3) is highly expressed in estrogen receptor-negative breast cancer, but the underlying mechanisms and consequences have not been thoroughly investigated. Here, we report that PLXNB3 expression is increased in response to hypoxia and that PLXNB3 is a direct target gene of hypoxia-inducible factor 1 (HIF-1) in human breast cancer cells. PLXNB3 expression is correlated with HIF-1α immunohistochemistry, breast cancer grade and stage, and patient mortality. Mechanistically, PLXNB3 is required for hypoxia-induced MET/SRC/focal adhesion kinase (FAK) and MET/SRC/STAT3/NANOG signaling as well as hypoxia-induced breast cancer cell migration, invasion, and cancer stem cell specification. PLXNB3 knockdown impairs tumor formation and lung metastasis in orthotopic breast cancer mouse models.

Chromosome-scale de novo genome assembly and annotation of three representative Casuarina species: C. equisetifolia, C. glauca, and C. cunninghamiana.

Australian pine (Casuarina spp.) is extensively planted in tropical and subtropical regions for wood production, shelterbelts, environmental protection, and ecological restoration due to their superior biological characteristics, such as rapid growth, wind and salt tolerance, and nitrogen fixation. To analyze the genomic diversity of Casuarina, we sequenced the genomes and constructed de novo genome assemblies of the three most widely planted Casuarina species: C. equisetifolia, C. glauca, and C. cunninghamiana. We generated chromosome-scale genome sequences using both Pacific Biosciences (PacBio) Sequel sequencing and chromosome conformation capture technology (Hi-C). The total genome sizes for C. equisetifolia, C. glauca, and C. cunninghamiana are 268 942 579 bp, 296 631 783 bp, and 293 483 606 bp, respectively, of which 25.91, 27.15, and 27.74% were annotated as repetitive sequences. We annotated 23 162, 24 673, and 24 674 protein-coding genes in C. equisetifolia, C. glauca, and C. cunninghamiana, respectively. We then collected branchlets from male and female individuals for whole-genome bisulfite sequencing (BS-seq) to explore the epigenetic regulation of sex determination in these three species. Transcriptome sequencing (RNA-seq) revealed differential expression of phytohormone-related genes between male and female plants. In summary, we generated three chromosome-level genome assemblies and comprehensive DNA methylation and transcriptome datasets from both male and female material for three Casuarina species, providing a basis for the comprehensive investigation of genomic diversity and functional gene discovery of Casuarina in the future.

Human fetal mesenchymal stem cells secretome promotes scarless diabetic wound healing through heat-shock protein family.

The high mortality rate of patients with diabetic foot ulcers is urging the appearance of an effective biomedical drug. Senescence is one of the major reasons of aging-induced decline in the diabetic wound. Our previous studies have demonstrated the anti-senescence effect of secretomes derived from human fetal mesenchymal stem cells (hfMSC). The present study tends to explore the potential role of hfMSC secretome (HFS) in wound healing through anti-aging. Meanwhile, we try to overcome several obstacles in the clinical application of stem cell secretome. A verticle bioreactor and microcarriers are employed to expand hfMSC and produce the HFS on a large scale. The HFS was then subjected to lyophilization (L-HFS). The PLGA (poly lactic-co-glycolic acid) particles were used to encapsulate and protect L-HFS from degradation in the streptozotocin (STZ)-induced diabetic rat model. Results showed that HFS-PLGA significantly enhanced wound healing by promoting vascularization and inhibiting inflammation in the skin wound bed. We further analyzed the contents of HFS. Isobaric tag for relative and absolute quantitation (ITRAQ) and label-free methods were used to identify peptides in the secretome. Bioinformatics analysis indicated that exosome production-related singling pathways and heat-shock protein family could be used as bio-functional markers and quality control for stem cell secretome production.

Enhancing cartilage repair with optimized supramolecular hydrogel-based scaffold and pulsed electromagnetic field.

Functional tissue engineering strategies provide innovative approach for the repair and regeneration of damaged cartilage. Hydrogel is widely used because it could provide rapid defect filling and proper structure support, and is biocompatible for cell aggregation and matrix deposition. Efforts have been made to seek suitable scaffolds for cartilage tissue engineering. Here Alg-DA/Ac-ß-CD/gelatin hydrogel was designed with the features of physical and chemical multiple crosslinking and self-healing properties. Gelation time, swelling ratio, biodegradability and biocompatibility of the hydrogels were systematically characterized, and the injectable self-healing adhesive hydrogel were demonstrated to exhibit ideal properties for cartilage repair. Furthermore, the new hydrogel design introduces a pre-gel state before photo-crosslinking, where increased viscosity and decreased fluidity allow the gel to remain in a semi-solid condition. This granted multiple administration routes to the hydrogels, which brings hydrogels the ability to adapt to complex clinical situations. Pulsed electromagnetic fields (PEMF) have been recognized as a promising solution to various health problems owing to their noninvasive properties and therapeutic potentials. PEMF treatment offers a better clinical outcome with fewer, if any, side effects, and wildly used in musculoskeletal tissue repair. Thereby we propose PEMF as an effective biophysical stimulation to be 4th key element in cartilage tissue engineering. In this study, the as-prepared Alg-DA/Ac-ß-CD/gelatin hydrogels were utilized in the rat osteochondral defect model, and the potential application of PEMF in cartilage tissue engineering were investigated. PEMF treatment were proven to enhance the quality of engineered chondrogenic constructs in vitro, and facilitate chondrogenesis and cartilage repair in vivo. All of the results suggested that with the injectable self-healing adhesive hydrogel and PEMF treatment, this newly proposed tissue engineering strategy revealed superior clinical potential for cartilage defect treatment.

NARF is a hypoxia-induced coactivator for OCT4-mediated breast cancer stem cell specification.

Hypoxia is a key characteristic of the breast cancer microenvironment that promotes expression of the transcriptional activator hypoxia-inducible factor 1 (HIF-1) and is associated with poor patient outcome. HIF-1 increases the expression or activity of stem cell pluripotency factors, which control breast cancer stem cell (BCSC) specification and are required for cancer metastasis. Here, we identify nuclear prelamin A recognition factor (NARF) as a hypoxia-inducible, HIF-1 target gene in human breast cancer cells. NARF functions as an essential coactivator by recruiting the histone demethylase KDM6A to OCT4 bound to genes encoding the pluripotency factors NANOG, KLF4, and SOX2, leading to demethylation of histone H3 trimethylated at lysine-27 (H3K27me3), thereby increasing the expression of NANOG, KLF4, and SOX2, which, together with OCT4, mediate BCSC specification. Knockdown of NARF significantly decreased the BCSC population in vitro and markedly impaired tumor initiation capacity and lung metastasis in orthotopic mouse models.

Transcriptome Profiling of Stem-Differentiating Xylem in Response to Abiotic Stresses Based on Hybrid Sequencing in Cunninghamia lanceolata.

Cunninghamia lanceolata (C. lanceolata) belongs to Gymnospermae, which are fast-growing and have desirable wood properties. However, C. lanceolata's stress resistance is little understood. To unravel the physiological and molecular regulation mechanisms under environmental stresses in the typical gymnosperm species of C. lanceolata, three-year-old plants were exposed to simulated drought stress (polyethylene glycol 8000), salicylic acid, and cold treatment at 4 °C for 8 h, 32 h, and 56 h, respectively. Regarding the physiological traits, we observed a decreased protein content and increased peroxidase upon salicylic acid and polyethylene glycol treatment. Superoxide dismutase activity either decreased or increased at first and then returned to normal under the stresses. Regarding the molecular regulation, we used both nanopore direct RNA sequencing and short-read sequencing to reveal a total of 5646 differentially expressed genes in response to different stresses, of which most had functions in lignin catabolism, pectin catabolism, and xylan metabolism, indicating that the development of stem-differentiating xylem was affected upon stress treatment. Finally, we identified a total of 51 AP2/ERF, 29 NAC, and 37 WRKY transcript factors in C. lanceolata. The expression of most of the NAC TFs increased under cold stress, and the expression of most of the WRKY TFs increased under cold and SA stress. These results revealed the transcriptomics responses in C. lanceolata to short-term stresses under this study's experimental conditions and provide preliminary clues about stem-differentiating xylem changes associated with different stresses.

Dietary Se-Enriched Cardamine enshiensis Supplementation Alleviates Transport-Stress-Induced Body Weight Loss, Anti-Oxidative Capacity and Meat Quality Impairments of Broilers.

The aim of this experiment was to explore the effects of a new selenium (Se) source from Se-enriched Cardamine enshiensis (SeCe) on body weight loss, anti-oxidative capacity and meat quality of broilers under transport stress. A total of 240 one-day-old ROSS 308 broilers were allotted into four treatments with six replicate cages and 10 birds per cage using a 2 × 2 factorial design. The four groups were as follows: (1) Na2SeO3-NTS group, dietary 0.3 mg/kg Se from Na2SeO3 without transport stress, (2) SeCe-NTS group, dietary 0.3 mg/kg Se from SeCe without transport stress, (3) Na2SeO3-TS group, dietary 0.3 mg/kg Se from Na2SeO3 with transport stress, and (4) SeCe-TS group, dietary 0.3 mg/kg Se from SeCe with transport stress. After a 42 d feeding period, the broilers were transported by a lorry or kept in the original cages for 3 h, respectively. The results showed that dietary SeCe supplementation alleviated transport-stress-induced body weight loss and hepatomegaly of the broilers compared with the broilers fed Na2SeO3 diets (p < 0.05). Furthermore, dietary SeCe supplementation increased the concentrations of plasma total protein and glucose, and decreased the activities of aspartate aminotransferase and alanine aminotransferase of the broilers under transport stress (p < 0.05). Dietary SeCe supplementation also enhanced the anti-oxidative capacity and meat quality in the breast and thigh muscles of the broilers under transport stress (p < 0.05). In summary, compared with Na2SeO3, dietary SeCe supplementation alleviates transport-stress-induced body weight loss, anti-oxidative capacity and meat quality impairments of broilers.

Development and validation of a nomogram to predict anastomotic leakage in colorectal cancer based on CT body composition.

Background: Anastomotic leakage (AL) is one of the most serious postoperative complications. This study aimed to investigate the predictive value of preoperative body composition for AL in patients with colorectal cancer (CRC). Methods: We first reviewed data from 3,681 patients who underwent radical CRC resection 2013-2021 in our hospital, and 60 patients were diagnosed with AL after surgery. We designed a nested case-control study and two controls were randomly selected for each case according to the time and position of surgery. Body composition was measured at the level of the third lumbar vertebra based on computed tomography (CT) images. The risk factors of AL were analyzed by univariate and multivariate analysis. Nomogram was built using binary regression analysis and assessed for clinical usefulness, calibration, and discrimination. Results: In the multivariate analysis, gender, blood glucose, nutrition risk screening (NRS), skeletal muscle area (SMA) and visceral fat area (VFA) were independent risk factors for developing anastomotic leakage after surgery. The prognostic model had an area under the receiver operating characteristic curve of 0.848 (95% CI, 0.781-0.914). The calibration curve showed good consistency between the predicted and observed outcomes. Decision curve analysis indicated that patients with colorectal cancer can benefit from the prediction model. Conclusions: The nomogram that combined with gender, blood glucose, NRS, SMA, and VFA had good predictive accuracy and reliability to AL. It may be conveniently for clinicians to predict AL preoperatively and be useful for guiding treatment decisions.

Development of Enzyme-Free DNA Amplifier Based on Chain Reaction Principle.

Enzyme-free DNA amplifiers can amplify the signal of nucleic acid molecules. They can be applied to DNA molecular operation and nucleic acid detection. The reaction speed is the core index to evaluate DNA amplifiers. In this study, we designed a DNA amplifier based on an enzyme-free chain reaction. This DNA amplifier can release one more signal molecule in each round of reaction and trigger the next round, which significantly improved reaction speed. Moreover, because the amplifier used a stable DNA structure, the reaction can occur at room temperature. To integrate the amplifier into other DNA molecular operations, we performed the amplification reaction in a microfluidic chip module. The results showed that the amplifier can realize real-time signal feedback at a proper input molecule concentration and reach the endpoint in 40 s, even at a low relative concentration. To apply the amplifier for nucleic acid detection, we also used a conventional fluorescent polymerase chain reaction instrument for the reaction. The results showed that the amplifier specifically detected trace DNA single-stranded molecules. To solve the leakage problem of existing amplifiers, we designed a DNA molecule as the chain reaction's inhibitor, which was crucial in controlling the reaction speed and preventing leakage. STATEMENT OF SIGNIFICANCE: Traditional amplifier strategies of enzyme-free DNA amplifiers relied on a constant number of cycling molecules to catalyze the amplifier molecules' changing structure and release fluorescent signals, which lead low reaction speed. Based on an enzyme-free chain reaction, we designed a DNA amplifier which can release one more cycling molecule in each loop and trigger the next loop and significantly improve reaction speed in this study. Our analysis on microfluidic chip module and PCR instrument verifies high sensitivity and selectivity. And this strategy of DNA amplifier realizes the control of reaction and prevents leakage. We believe that this automated amplification strategy could have great applications in vivo signal detection, imaging, and signal molecule translation.