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This study addresses the need for inclusive AI education by focusing on marginalized female students who historically lack access to learning opportunities in computing. It applies the theoretical framework of intersectionality to understand how gender, race and ethnicity intersect to shape these students' learning experiences and outcomes. Specifically, this study investigated 27 high‐school students' cognitive engagement in machine learning practices. We conducted the Wilcoxon–Mann–Whitney test to explore differences in cognitive engagement between marginalized female students and their peers, employed comparative content analysis to delve into significant differences and analysed interview data thematically to gain deeper insights into students' machine learning model development processes. The findings indicated that, when engaging in machine learning practices requiring drawing diverse cultural perspectives, marginalized female students demonstrated significantly higher performance compared to their peers. In particular, marginalized female students exhibited strengths in holistic language analysis, paying attention to writers' intentions and recognizing cultural nuances in language. This study suggests that integrating language analysis and machine learning across subjects has the potential to empower marginalized female students and amplify their perspectives. Furthermore, it calls for a strengths‐based approach to reshape the narrative of underrepresentation and promote equitable participation in machine learning and AI. Practitioner notesWhat is already known about this topic Female students, particularly those from underrepresented groups such as African American and Latina students, often experience low levels of cognitive engagement in computing.Marginalized female students possess unique strengths that, when nurtured, have the potential to not only transform their own learning experiences but also contribute to the advancement of the computing field.It is critical to empower marginalized female students in K‐12 AI (ie, a subfield of computing) education, seeking to bridge the gender and racial disparity in AI.What this paper adds Marginalized female students outperformed their peers in responding to machine learning questions related to feature analysis and feature distribution interpretation.When responding to these questions, they demonstrated a holistic approach to analysing language by considering interactions between features and writers' intentions.They drew on knowledge about how language was used to convey meaning in different cultural contexts.Implications for practice and/or policy Educators should design learning environments that encourage students to draw upon their cultural backgrounds, linguistic insights and diverse experiences to enhance their engagement and performance in AI‐related activities.Educators should strategically integrate language analysis and machine learning across different subjects to create interdisciplinary learning experiences that support students' exploration of the interplay among language, culture and AI.Educational institutions and policy initiatives should adopt a strengths‐based approach that focuses on empowering marginalized female students by acknowledging their inherent abilities and diverse backgrounds. [ABSTRACT FROM AUTHOR]

The development of acute respiratory distress syndrome (ARDS) in sepsis is associated with substantial morbidity and mortality. However, the molecular pathogenesis underlying sepsis‐induced ARDS remains elusive. Neutrophil heterogeneity and dysfunction contribute to uncontrolled inflammation in patients with ARDS. A specific subset of neutrophils undergoing reverse transendothelial migration (rTEM), which is characterized by an activated phenotype, is implicated in the systemic dissemination of inflammation. Using single‐cell RNA sequencing (scRNA‐seq), it identified functionally activated neutrophils exhibiting the rTEM phenotype in the lung of a sepsis mouse model using cecal ligation and puncture. The prevalence of neutrophils with the rTEM phenotype is elevated in the blood of patients with sepsis‐associated ARDS and is positively correlated with disease severity. Mechanically, scRNA‐seq and proteomic analys revealed that inflamed endothelial cell (EC) released extracellular vesicles (EVs) enriched in karyopherin subunit beta‐1 (KPNB1), promoting abluminal‐to‐luminal neutrophil rTEM. Additionally, EC‐derived EVs are elevated and positively correlated with the proportion of rTEM neutrophils in clinical sepsis. Collectively, EC‐derived EV is identified as a critical regulator of neutrophil rTEM, providing insights into the contribution of rTEM neutrophils to sepsis‐associated lung injury. [ABSTRACT FROM AUTHOR]

Background: Uncontrolled inflammation caused by macrophages and monocytes plays a crucial role in worsening acute respiratory distress syndrome (ARDS). Previous studies have highlighted the importance of IFIH1 in regulating macrophage polarisation in ARDS triggered by pneumonia. However, the mechanisms by which IFIH1 is activated in ARDS remain unclear. Methods: In this study, we utilised multiomics sequencing and molecular interaction experiments to explore the molecular mechanisms underlying IFIH1 activation in ARDS. Through the use of conditional gene knockout mice and primary cells, we demonstrated the significant role of these mechanisms in the development of ARDS. Additionally, we validated the associations between these mechanisms and ARDS by quantitative PCR analysis of CD14+ cells obtained from the peripheral blood of 140 ARDS patients. Results: Our investigation revealed that lipopolysaccharide, a critical component derived from Gram‐negative bacteria, activated IFIH1 by upregulating a novel transcript known as IFIH1‐binding RNA1 (IBR1) in monocytes and macrophages. Specifically, as an endogenous double‐stranded RNA, IBR1 bind to the helicase domain of IFIH1 because of its unique double‐stranded structure. Deletion of IBR1 significantly reduced the activation of IFIH1, M1 polarisation of macrophages, and inflammatory lung injury in ARDS. Moreover, IBR1 directly induced M1 polarisation of macrophages and ARDS, whereas deletion of IFIH1 inhibited IBR1‐induced macrophage M1 polarisation and inflammatory lung injury. Importantly, we observed a notable increase in IBR1 expression in ARDS patients with pneumonia caused by Gram‐negative bacteria. Furthermore, we demonstrated that the delivery of IFIH1 mutants through exosomes effectively counteracted IBR1, thereby reducing pulmonary inflammation and alleviating lung injury. Conclusions: This study revealed a novel mechanism involving IBR1, an endogenous double‐stranded RNA (dsRNA) that binds to IFIH1, shedding light on the complex process of macrophage polarisation in ARDS. The administration of IFIH1 variants has the potential to eliminate pulmonary dsRNA and alleviate inflammatory lung injury in ARDS. Highlights: In monocytes and macrophages, the endogenous double‐stranded RNA, IFIH1‐binding RNA 1 (IBR1), binds to the helicase domain of IFIH1 because of its unique double‐stranded structure.IBR1 plays a significant role in macrophage polarisation and the development of acute respiratory distress syndrome (ARDS) induced by Gram‐negative bacteria or lipopolysaccharide (LPS).Administration of IFIH1 variants has potential for eliminating pulmonary IBR1 and reducing inflammatory lung injury in ARDS patients. [ABSTRACT FROM AUTHOR]

The cooperative diagnosis of non‐coding RNAs (ncRNAs) can accurately reflect the state of cell differentiation and classification, laying the foundation of precision medicine. However, there are still challenges in simultaneous analyses of multiple ncRNAs and the integration of biomarker data for cell typing. In this study, DNA framework‐based programmable atom‐like nanoparticles (PANs) are designed to develop molecular classifiers for intra‐cellular imaging of multiple ncRNAs associated with cell differentiation. The PANs‐based molecular classifier facilitates signal amplification through the catalytic hairpin assembly. The interaction between PAN reporters and ncRNAs enables high‐fidelity conversion of ncRNAs expression level into binding events, and the assessment of in situ ncRNAs levels via measurement of the fluorescent signal changes of PAN reporters. Compared to non‐amplified methods, the detection limits of PANs are reduced by four orders of magnitude. Using human gastric cancer cell lines as a model system, the PANs‐based molecular classifier demonstrates its capacity to measure multiple ncRNAs in living cells and assesses the degree of cell differentiation. This approach can serve as a universal strategy for the classification of cancer cells during malignant transformation and tumor progression. [ABSTRACT FROM AUTHOR]

High temperatures (>24°C) prevent the development of a yellow peel on bananas called green ripening, owing to the inhibition of chlorophyll degradation. This phenomenon greatly reduces the marketability of banana fruit, but the mechanisms underlining high temperature‐repressed chlorophyll catabolism need to be elucidated. Herein, we found that the protein accumulation of chlorophyll catabolic enzyme MaSGR1 (STAY‐GREEN 1) was reduced when bananas ripened at high temperature. Transiently expressing MaSGR1 in banana peel showed its positive involvement in promoting chlorophyll degradation under high temperature, thereby weakening green ripening phenotype. Using yeast two‐hybrid screening, we identified a RING‐type E3 ubiquitin ligase, MaRZF1 (RING Zinc Finger 1), as a putative MaSGR1‐interacting protein. MaRZF1 interacts with and targets MaSGR1 for ubiquitination and degradation via the proteasome pathway. Moreover, upregulating MaRZF1 inhibited chlorophyll degradation, and attenuated MaSGR1‐promoted chlorophyll degradation in bananas during green ripening, indicating that MaRZF1 negatively regulates chlorophyll catabolism via the degradation of MaSGR1. Taken together, MaRZF1 and MaSGR1 form a regulatory module to mediate chlorophyll degradation associated with high temperature‐induced green ripening in bananas. Therefore, our findings expand the understanding of posttranslational regulatory mechanisms of temperature stress‐caused fruit quality deterioration. Summary statement: RING‐type ubiquitin E3 ligase MaRZF1 interacts with chlorophyll catabolic enzyme MaSGR1, which promotes the ubiquitination and proteasomal degradation of MaSGR1, causing the green ripening of banana fruit under high temperature. [ABSTRACT FROM AUTHOR]

Sinapic acid (SA) is renowned for its many pharmacological activities as a polyphenolic compound. The cause of polycystic ovary syndrome (PCOS), a commonly encountered array of metabolic and hormonal abnormalities in females, has yet to be determined. The present experiment was performed to evaluate the antifibrotic properties of SA in rats with letrozole‐induced PCOS‐related ovarian fibrosis. SA treatment successfully mitigated the changes induced by letrozole in body weight (BW) (p <.01) and relative ovary weight (p <.05). Histological observation revealed that SA reduced the number of atretic and cystic follicles (AFs) and (CFs) (p <.01), as well as ovarian fibrosis, in PCOS rats. Additionally, SA treatment impacted the serum levels of sex hormones in PCOS rats. Luteinizing hormone (LH) and testosterone (T) levels were decreased (p <.01, p <.05), and follicle‐stimulating hormone (FSH) levels were increased (p <.05). SA administration also decreased triglyceride (TG) (p <.01) and total cholesterol (TC) levels (p <.05) and increased high‐density lipoprotein cholesterol (HDL‐C) levels (p <.01), thereby alleviating letrozole‐induced metabolic dysfunction in PCOS rats. Furthermore, SA treatment targeted insulin resistance (IR) and increased the messenger RNA (mRNA) levels of antioxidant enzymes in the ovaries of PCOS rats. Finally, SA treatment enhanced the activity of peroxisome proliferator‐activated receptor‐γ (PPAR‐γ), reduced the activation of transforming growth factor‐β1 (TGF‐β1)/Smads, and decreased collagen I, α‐smooth muscle actin (α‐SMA), and connective tissue growth factor (CTGF) levels in the ovaries of PCOS rats. These observations suggest that SA significantly ameliorates metabolic dysfunction and oxidative stress and ultimately reduces ovarian fibrosis in rats with letrozole‐induced PCOS. [ABSTRACT FROM AUTHOR]

Acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) is a common life‐threatening syndrome with no effective pharmacotherapy. Sepsis‐related ARDS is the main type of ARDS and is more fatal than other types. Extracellular vesicles (EVs) are considered novel mediators in the development of inflammatory diseases. Our previous research suggested that endothelial cell‐derived EVs (EC‐EVs) play a crucial role in ALI/ARDS development, but the mechanism remains largely unknown. Here, we demonstrated that the number of circulating EC‐EVs was increased in sepsis, exacerbating lung injury by targeting monocytes and reprogramming them towards proinflammatory macrophages. Bioinformatics analysis and further mechanistic studies revealed that vascular cell adhesion molecule 1 (VCAM1), overexpressed on EC‐EVs during sepsis, activated the NF‐κB pathway by interacting with integrin subunit alpha 4 (ITGA4) on the monocyte surface, rather than the tissue resident macrophage surface, thereby regulating monocyte differentiation. This effect could be attenuated by decreasing VCAM1 levels in EC‐EVs or blocking ITGA4 on monocytes. Furthermore, the number of VCAM1+ EC‐EVs was significantly increased in patients with sepsis‐related ARDS. These findings not only shed light on a previously unidentified mechanism underling sepsis‐related ALI/ARDS, but also provide potential novel targets and strategies for its precise treatment. [ABSTRACT FROM AUTHOR]

Background: Hypertrophic cardiomyopathy (HCM) is a common cardiac genetic disorder that clinically manifests with sudden death and progressive heart failure. Moreover, thyroid dysfunction is associated with increased cardiovascular morbidity and mortality risks. Therefore, this study aimed to clarify whether thyroid hormones could serve as an independent predictor of adverse events in patients with HCM. Methods: The cohort consisted of 782 patients with HCM who had thyroid hormones baseline data and were admitted to the Affiliated Hospital of Jiaxing University. Patients were divided into two groups according to serum levels of free triiodothyronine (fT3): the normal fT3 and low triiodothyronine (T3) syndrome groups. Low T3 syndrome was defined as fT3 < 2.43 pmol/L with a normal thyroid‐stimulating hormone (TSH) level. Patients whose TSH levels were abnormally high or abnormally low were excluded from this study. The primary endpoint was the occurrence of sudden cardiac death (SCD) events, and the secondary endpoint was a composite of worsening heart failure (WHF) events, including heart failure death, cardiac decompensation, hospitalization for heart failure, and HCM‐related stroke. The Kaplan–Meier and Cox regression were performed for the survival analysis. Results: After a median follow‐up of 52 months, 75 SCD events and 134 WHF events were recorded. The Kaplan–Meier survival curves showed that the cumulative incidence of SCD events and WHF events were significantly higher in patients with low T3 syndrome (log‐rank p =.02 and log‐rank p =.001, respectively). Furthermore, multivariate Cox regression analysis demonstrated that low T3 syndrome is a strong predictor of SCD events and WHF events (adjusted hazard ratio [HR: 1.53, 95% confidence interval [CI]: 1.13–2.24, p <.01; HR: 3.87, 95% CI: 2.91–4.98, p <.001, respectively). Conclusions: Low T3 syndrome is highly prevalent among patients with HCM and was independently associated with an increased risk of SCD events and WHF events. The routine assessment of serum fT3 levels may provide risk stratification in this population. [ABSTRACT FROM AUTHOR]

Text provides a compelling example of unstructured data that can be used to motivate and explore classification problems. Challenges arise regarding the representation of features of text and student linkage between text representations as character strings and identification of features that embed connections with underlying phenomena. In order to observe how students reason with text data in scenarios designed to elicit certain aspects of the domain, we employed a task‐based interview method using a structured protocol with six pairs of undergraduate students. Our goal was to shed light on students' understanding of text as data using a motivating task to classify headlines as "clickbait" or "news." Three types of features (function, content, and form) surfaced, the majority from the first scenario. Our analysis of the interviews indicates that this sequence of activities engaged the participants in thinking at both the human‐perception level and the computer‐extraction level and conceptualizing connections between them. [ABSTRACT FROM AUTHOR]

To date, many AI initiatives (eg, AI4K12, CS for All) developed standards and frameworks as guidance for educators to create accessible and engaging Artificial Intelligence (AI) learning experiences for K‐12 students. These efforts revealed a significant need to prepare youth to gain a fundamental understanding of how intelligence is created, applied, and its potential to perpetuate bias and unfairness. This study contributes to the growing interest in K‐12 AI education by examining student learning of modelling real‐world text data. Four students from an Advanced Placement computer science classroom at a public high school participated in this study. Our qualitative analysis reveals that the students developed nuanced and in‐depth understandings of how text classification models—a type of AI application—are trained. Specifically, we found that in modelling texts, students: (1) drew on their social experiences and cultural knowledge to create predictive features, (2) engineered predictive features to address model errors, (3) described model learning patterns from training data and (4) reasoned about noisy features when comparing models. This study contributes to an initial understanding of student learning of modelling unstructured data and offers implications for scaffolding in‐depth reasoning about model decision making. Practitioner notes: What is already known about this topic Scholarly attention has turned to examining Artificial Intelligence (AI) literacy in K‐12 to help students understand the working mechanism of AI technologies and critically evaluate automated decisions made by computer models.While efforts have been made to engage students in understanding AI through building machine learning models with data, few of them go in‐depth into teaching and learning of feature engineering, a critical concept in modelling data.There is a need for research to examine students' data modelling processes, particularly in the little‐researched realm of unstructured data. What this paper adds Results show that students developed nuanced understandings of models learning patterns in data for automated decision making.Results demonstrate that students drew on prior experience and knowledge in creating features from unstructured data in the learning task of building text classification models.Students needed support in performing feature engineering practices, reasoning about noisy features and exploring features in rich social contexts that the data set is situated in. Implications for practice and/or policy It is important for schools to provide hands‐on model building experiences for students to understand and evaluate automated decisions from AI technologies.Students should be empowered to draw on their cultural and social backgrounds as they create models and evaluate data sources.To extend this work, educators should consider opportunities to integrate AI learning in other disciplinary subjects (ie, outside of computer science classes). [ABSTRACT FROM AUTHOR]

SUMMARY: Fruit ripening is a complex developmental process, which is modulated by both transcriptional and post‐translational events. Control of fruit ripening is important in maintaining moderate quality traits and minimizing postharvest deterioration. In this study, we discovered that the transcription factor MaMYB4 acts as a negative regulator of fruit ripening in banana. The protein levels of MaMYB4 decreased gradually with banana fruit ripening, paralleling ethylene production, and decline in firmness. DNA affinity purification sequencing combined with RNA‐sequencing analyses showed that MaMYB4 preferentially binds to the promoters of various ripening‐associated genes including ethylene biosynthetic and cell wall modifying genes. Furthermore, ectopic expression of MaMYB4 in tomato delayed tomato fruit ripening, which was accompanied by downregulation of ethylene biosynthetic and cell wall modifying genes. Importantly, two RING finger E3 ligases MaBRG2/3, whose protein accumulation increased progressively with fruit ripening, were found to interact with and ubiquitinate MaMYB4, contributing to decreased accumulation of MaMYB4 during fruit ripening. Transient overexpression of MaMYB4 and MaBRG2/3 in banana fruit ripening delayed or promoted fruit ripening by inhibiting or stimulating ethylene biosynthesis, respectively. Taken together, we demonstrate that MaMYB4 negatively modulates banana fruit ripening, and that MaMYB4 abundance could be regulated by protein ubiquitination, thus providing insights into the role of MaMYB4 in controlling fruit ripening at both transcriptional and post‐translational levels. [ABSTRACT FROM AUTHOR]

The development of DNA nanotechnology has attracted tremendous attention in biotechnological and biomedical fields involving biosensing, bioimaging and disease therapy. In particular, precise control over size and shape, easy modification, excellent programmability and inherent homology make the sophisticated DNA nanostructures vital for constructing intelligent drug carriers. Recent advances in the design of multifunctional DNA‐based drug delivery systems (DDSs) have demonstrated the effectiveness and advantages of DNA nanostructures, showing the unique benefits and great potential in enhancing the delivery of pharmaceutical compounds and reducing systemic toxicity. This Review aims to overview the latest researches on DNA nanotechnology‐enabled nanomedicine and give a perspective on their future opportunities. [ABSTRACT FROM AUTHOR]

Major depressive disorder (MDD) is the most prevalent psychiatric disorder worldwide and severely limits psychosocial function and quality of life, but no effective medication is currently available. Circular RNAs (circRNAs) have been revealed to participate in the MDD pathological process. Targeted delivery of circRNAs without blood‐brain barrier (BBB) restriction for remission of MDD represents a promising approach for antidepressant therapy. In this study, RVG‐circDYM‐extracellular vesicles (RVG‐circDYM‐EVs) were engineered to target and preferentially transfer circDYM to the brain, and the effect on the pathological process in a chronic unpredictable stress (CUS) mouse model of depression was investigated. The results showed that RVG‐circDYM‐EVs were successfully purified by ultracentrifugation from overexpressed circDYM HEK 293T cells, and the characterization of RVG‐circDYM‐EVs was successfully demonstrated in terms of size, morphology and specific markers. Beyond demonstrating proof‐of‐concept for an RNA drug delivery technology, we observed that systemic administration of RVG‐circDYM‐EVs efficiently delivered circDYM to the brain, and alleviated CUS‐induced depressive‐like behaviours, and we discovered that RVG‐circDYM‐EVs notably inhibited microglial activation, BBB leakiness and peripheral immune cells infiltration, and attenuated astrocyte disfunction induced by CUS. CircDYM can bind mechanistically to the transcription factor TAF1 (TATA‐box binding protein associated factor 1), resulting in the decreased expression of its downstream target genes with consequently suppressed neuroinflammation. Taken together, our findings suggest that extracellular vesicle‐mediated delivery of circDYM is effective for MDD treatment and promising for clinical applications. [ABSTRACT FROM AUTHOR]

Background: Glioma stem‐like cells (GSCs) are greatly responsible for the progression of glioma. Long noncoding RNAs (lncRNAs) play an important role in glioma tumor progression. This study aims to explore the role and underlying mechanism of lncRNA SNHG9 in regulating GSC cell growth. Methods: GSCs were obtained from glioma cells (U87 and U251) and referred to as GSC‐87 and GSC‐251, respectively. The interactions between miR‐326 and SNHG9 or SOX9 were analyzed using luciferase reporter assay. Cell growth of GSCs was evaluated by EdU assay and sphere formation assay. Results: SNHG9 expression was significantly higher in GSC‐87 and GSC‐251 cells than in U87 and U251 cells. SNHG9 overexpression promoted GSC cell growth, whereas SNHG9 knockdown inhibited GSC cell growth. Mechanistically, SNHG9 acted as a competitive endogenous RNA of miR‐326 to elevate the expression of SOX9, a direct target of miR‐326. Moreover, transfection with miR‐326 inhibitor counteracted SNHG9 knockdown‐mediated inhibition of GSC cell growth. Conclusions: SNHG9 facilitates growth of GSCs via the miR‐326/SOX9 axis. This study provides a promising therapeutic target for glioma treatment. [ABSTRACT FROM AUTHOR]

BACKGROUND: Glyphosate has been used for weed control in South China in various situations for four decades, and most Eleusine indica populations are suspected to have evolved resistance to glyphosate. This research investigated underling target‐site glyphosate resistance mechanisms in six field‐collected, putative glyphosate‐resistant (R) E. indica populations. RESULTS: The six R E. indica populations were confirmed to be low (1.8 to 2.6‐fold) to moderately (5.6‐ to 8.4‐fold) resistant to glyphosate relative to the susceptible (S) population. Sixty‐seven glyphosate‐surviving plants from the six R populations were used to examine target‐site resistance mechanisms. Target‐site 5‐enolpyruvylshikimate3‐phosphate synthase (EPSPS) overexpression (OE) (plus further induction by glyphosate treatment) and gene copy number variation (CNV) occurred in 94% R plants, and among them, 16% had the P106A mutation and 49% had the heterozygous double TIPS (T102I + P106S) mutation (plus P381L). In addition, a low number of R plants (6%) only had the homologous TIPS (plus P381L) mutation. The (CT)6 insertion mutation in the EPSPS 5†‐UTR always associates with EPSPS OE and CNV. Progeny plants possessing EPSPS OE/CNV (and P106A) displayed low level (up to 4.5‐fold) glyphosate resistance. In contrast, plants homozygous for the TIPS mutation displayed higher (25‐fold) resistance to glyphosate and followed by plants heterozygous for this mutation plus EPSPS OE/CNV (12‐fold). CONCLUSIONS: Target‐site glyphosate resistance in E. indica populations from South China is common with prevalence of EPSPS OE/induction/CNV conferring low level resistance. Individual plants acquiring both the TIPS mutation and EPSPS OE/CNV are favored due to evolutionary advantages. The role of (CT)6 insertion mutation in EPSPS CNV is worth further investigation. © 2021 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Tetrahedral framework nucleic acids (tFNAs) are renowned for their controllable self‐assembly, exceptional programmability, and excellent biocompatibility, which have led to their widespread application in the biomedical field. Beyond these features, tFNAs demonstrate unique chemical and biological properties including high cellular uptake efficiency, structural bio‐stability, and tissue permeability, which are derived from their distinctive 3D structure. To date, an extensive range of tFNA‐based nanostructures are intelligently designed and developed for various biomedical applications such as drug delivery, gene therapy, biosensing, and tissue engineering, among other emerging fields. In addition to their role in drug delivery systems, tFNAs also possess intrinsic properties that render them highly effective as therapeutic agents in the treatment of complex diseases, including arthritis, neurodegenerative disorders, and cardiovascular diseases. This dual functionality significantly enhances the utility of tFNAs in biomedical research, presenting valuable opportunities for the development of next‐generation medical technologies across diverse therapeutic and diagnostic platforms. Consequently, this review comprehensively introduces the latest advancements of tFNAs in the biomedical field, with a focus on their benefits and applications as drug delivery nanoplatforms, and their inherent capabilities as therapeutic agents. Furthermore, the current limitations, challenges, and future perspectives of tFNAs are explored. [ABSTRACT FROM AUTHOR]

Because multifunctional ceramics are widely used in the electronics, manipulating composition and structure of the electronic ceramics aim at improving the performance of the target material for appropriate applications. However, the composite materials with multiphases and multicomponents could be achieved by mixing the nanomaterials with various preparing methods or technologies, which generally require a bunch of experimental design to obtain the target products. For achieving the goals, a novel electrochemical approach for preparing functional ceramic materials is demonstrated via ion extraction from the A site of perovskite BiFeO3 (BFO) ceramic particles, and whereby a single‐phase perovskite BFO could be evolved into multiphase and multicrystalline homogeneous composites. With gradual changes in material particle size, composition, structure, and morphology upon electrochemical Bi3+ ion extraction, the magnetic and electromagnetic properties of the decomposed BFO along with the generated multiphase and multicrystalline composites would present pronounced evolutionary behaviors, compared with original BFO. Apparently, such titration method upon electrochemical ion extraction could be employed to manipulate the properties of the functional ceramics. The simple strategy of electrochemical manipulation BFO would be applied to certain materials with electrochemical activity to achieve the target performance. [ABSTRACT FROM AUTHOR]

Metallic nanocube ensembles exhibit tunable localized surface plasmon resonance to induce the light manipulation at the subwavelength scale. Nevertheless, precisely control anisotropic metallic nanocube ensembles with relative spatial directionality remains a challenge. Here, we report a DNA origami based nanoprinting (DOBNP) strategy to transfer the essential DNA strands with predefined sequences and positions to the surface of the gold nanocubes (AuNCs). These DNA strands ensured the specific linkages between AuNCs and gold nanoparticles (AuNPs) that generating the stereo‐controlled AuNC‐AuNP nanostructures (AANs) with controlled geometry and composition. By anchoring the single dye molecule in hot spot regions, the dramatic enhanced electromagnetic field aroused stronger surface enhanced Raman scattering (SERS) signal amplification. Our approach opens the opportunity for the fabrication of stereo‐controlled metal nanostructures for designing highly sensitive photonic devices. [ABSTRACT FROM AUTHOR]

Main observation and conclusion: The investigation of Morinda officinalis led to the isolation of twelve compounds (1—12), including three new iridoid glycosides morindalins A—C (1—3) and nine known compounds (4—12). Their structural identifications were conducted using HRMS, 1D and 2D NMR, and electronic circular dichroism (ECD) spectra as well as quantum chemical computations. Compound 6 displayed the most significantly agonistic activity against farnesoid X receptor (FXR) with an EC50 value of 7.18 μM, and its agonistic effect was verified through the investigation of FXR downstream target genes including small heterodimer partner 1 (SHP1), bile salt export pump (BSEP), and organic solute transporter subunit alpha and beta (OSTα and OSTβ). The potential interaction of compound 6 with FXR was analyzed by molecular docking and molecular dynamics stimulation, revealing that amino acid residues Leu287, Thr288, and Ser332 played a crucial role in the activation of compound 6 towards FXR. These findings suggested that compound 6 could be regarded as a potential candidate for the development of FXR agonists. [ABSTRACT FROM AUTHOR]

Summary: Fruit ripening is a critical phase in the production and marketing of fruits. Previous studies have indicated that fruit ripening is a highly coordinated process, mainly regulated at the transcriptional level, in which transcription factors play essential roles. Thus, identifying key transcription factors regulating fruit ripening as well as their associated regulatory networks promises to contribute to a better understanding of fruit ripening. In this study, temporal gene expression analyses were performed to investigate banana fruit ripening with the aim to discern the global architecture of gene regulatory networks underlying fruit ripening. Eight time points were profiled covering dynamic changes of phenotypes, the associated physiology and levels of known ripening marker genes. Combining results from a weighted gene co‐expression network analysis (WGCNA) as well as cis‐motif analysis and supported by EMSA, Y1H, tobacco‐, banana‐transactivation experimental results, the regulatory network of banana fruit ripening was constructed, from which 25 transcription factors were identified as prime candidates to regulate the ripening process by modulating different ripening‐related pathways. Our study presents the first global view of the gene regulatory network involved in banana fruit ripening, which may provide the basis for a targeted manipulation of fruit ripening to attain higher banana and loss‐reduced banana commercialization. [ABSTRACT FROM AUTHOR]

High‐mobility group protein A2 (HMGA2) is highly expressed in hepatocellular carcinoma (HCC) cells and contributes to tumor metastasis and poor patient survival. However, the molecular mechanism through which HMGA2 is transcriptionally regulated in HCC cells remains largely unclear. Here, we showed that the expression HMGA2 was upregulated in HCC, and that elevated HMGA2 could promote tumor metastasis. Incubation of HCC cells with epidermal growth factor (EGF) could promote the expression of HMGA2 mRNA and protein. Mechanistic studies suggested that EGF can phosphorylate p300 at Ser1834 residue through the PI3K/Akt signaling pathway in HCC cells. Knockdown of p300 can reverse EGF‐induced HMGA2 expression and histone H3‐K9 acetylation, whereas a phosphorylation‐mimic p300 S1834D mutant can stimulate HMGA2 expression as well as H3‐K9 acetylation in HCC cells. Furthermore, we identified that p300‐mediated H3‐K9 acetylation participates in EGF‐induced HMGA2 expression in HCC. In addition, the levels of H3‐K9 acetylation positively correlated with the expression levels of HMGA2 in a chemically induced HCC model in rats and human HCC specimens. [ABSTRACT FROM AUTHOR]

Background: H7N9 avian influenza is an infection of public health concern, in part because of its high mortality rate and pandemic potential. Aims: To describe the clinical features of H7N9 avian influenza and the response to treatment. Methods: Clinical, radiological and histopathological data, and treatment‐related of H7N9‐infected patients hospitalised during 2014–2017 were extracted and analysed. Results: A total of 17 H7N9 patients (three females; mean age, 58.4 ± 13.7 years) was identified; of these six died. All patients presented with fever and productive cough; four patients had haemoptysis and 13 had chest distress and/or shortness of breath. Early subnormal white blood cell count and elevation of serum liver enzymes were common. Multilobar patchy shadows, rapid progression to ground‐glass opacities, air bronchograms and consolidation were the most common imaging findings. Histopathological examination of lung tissue of three patients who died showed severe alveolar epithelial cell damage, with inflammatory exudation into the alveolar space and hyaline membrane formation; widened alveolar septae, prominent inflammatory cell infiltration; and hyperplasia of pneumocytes. Viral inclusions were found in the lung tissue of two patients. All patients received antiviral drugs (oseltamivir ± peramivir). Four patients carried the rs12252‐C/C interferon‐induced transmembrane protein‐3 (IFITM3) genotype, while the others had the C/T genotype. Conclusions: H7N9 virus infection causes human influenza‐like symptoms, but may rapidly progress to severe pneumonia and even death. Clinicians should be alert to the possibility of H7N9 infection in high‐risk patients. The presence of the IFITM3 rs12252‐C genotype may predict severe illness. [ABSTRACT FROM AUTHOR]

Synthetic aperture radar (SAR) multi‐target interactive motion recognition classifies the type of interactive motion and generates descriptions of the interactive motions at the semantic level by considering the relevance of multi‐target motions. A method for SAR multi‐target interactive motion recognition is proposed, which includes moving target detection, target type recognition, interactive motion feature extraction, and multi‐target interactive motion type recognition. Wavelet thresholding denoising combined with a convolutional neural network (CNN) is proposed for target type recognition. The method performs wavelet thresholding denoising on SAR target images and then uses an eight‐layer CNN named EilNet to achieve target recognition. After target type recognition, a multi‐target interactive motion type recognition method is proposed. A motion feature matrix is constructed for recognition and a four‐layer CNN named FolNet is designed to perform interactive motion type recognition. A motion simulation dataset based on the MSTAR dataset is built, which includes four kinds of interactive motions by two moving targets. The experimental results show that the recognition performance of the authors' Wavelet + EilNet method for target type recognition and FolNet for multi‐target interactive motion type recognition are both better than other methods. Thus, the proposed method is an effective method for SAR multi‐target interactive motion recognition. [ABSTRACT FROM AUTHOR]

Kaempferol (kaem) is a dietary flavonoid found in a variety of fruits and vegetables. The inhibitory effects of kaem on primary tumour growth have been extensively investigated; however, its effects on tumour metastasis are largely unknown. In the present study, we found that kaem significantly suppresses both primary tumour growth and lung metastasis in mouse breast tumour model. Furthermore, decreased expression of citrullinated histone H3 (H3‐cit), a biomarker of neutrophil extracellular traps (NETs), had been founded in metastatic lung upon treated with kaem. The reduction of H3‐cit is not, however, due to the cytotoxicity of kaem on neutrophils since the frequency of CD11b+Ly6G+ neutrophils did not change in lung, tumour or blood in the presence of kaem. We then confirm the anti‐NETs effects of kaem in vitro by co‐culturing mouse neutrophils and kaem. Supplementing the neutrophils with GSK484, a potent NET inhibitor, totally abrogated the inhibitory effects of kaem on tumour metastasis while having little or no impact on primary tumour growth, indicating the specificity of kaem acting on NET formation and tumour metastasis. We also found that kaem suppressed ROS production in mouse bone‐marrow derived neutrophils. Supplementing with the ROS scavenger DPI abrogated kaem's effects on NET formation, suggesting the involvement of kaempferol in NADPH/ROS‐NETs signalling. Finally, we applied the kaem on NET‐deficient PAD4‐/‐ mice and found decreased primary tumour volume and weight but similar lung metastatic tumour with kaempferol treatment. Therefore, our findings reveal a novel mechanism of kaem in breast cancer development by targeting NETs induced tumour metastasis. [ABSTRACT FROM AUTHOR]

Summary Transcriptional regulation mechanisms underlying chilling injury (CI) development have been widely investigated in model plants and cold‐sensitive fruits, such as banana (Musa acuminata). However, unlike the well‐known NAC and WRKY transcription factors (TFs), the function and deciphering mechanism of heat shock factors (HSFs) involving in cold response are still fragmented. Here, we showed that hot water treatment (HWT) alleviated CI in harvested banana fruits accomplishing with reduced reactive oxygen species (ROS) accumulation and increased antioxidant enzyme activities. A cold‐inducible but HWT‐inhibited HSF, MaHsf24, was identified. Using DNA affinity purification sequencing (DAP‐seq) combined with RNA‐seq analyses, we found three heat shock protein (HSP) genes (MaHSP23.6, MaHSP70‐1.1 and MaHSP70‐1.2) and three antioxidant enzyme genes (MaAPX1, MaMDAR4 and MaGSTZ1) were the potential targets of MaHsf24. Subsequent electrophoretic mobility shift assay (EMSA), chromatin immunoprecipitation coupled with quantitative PCR (ChIP‐qPCR) and dual‐luciferase reporter (DLR) analyses demonstrated that MaHsf24 repressed the transcription of these six targets via directly binding to their promoters. Moreover, stably overexpressing MaHsf24 in tomatoes increased cold sensitivity by suppressing the expressions of HSPs and antioxidant enzyme genes, while HWT could recover cold tolerance, maintaining higher levels of HSPs and antioxidant enzyme genes, and activities of antioxidant enzymes. In contrast, transiently silencing MaHsf24 by virus‐induced gene silencing (VIGS) in banana peels conferred cold resistance with the upregulation of MaHSPs and antioxidant enzyme genes. Collectively, our findings support the negative role of MaHsf24 in cold tolerance, and unravel a novel regulatory network controlling bananas CI occurrence, concerning MaHsf24‐exerted inhibition of MaHSPs and antioxidant enzyme genes. [ABSTRACT FROM AUTHOR]

Banana fruit (Musa acuminate L.) ripening is a complex genetical process affected by multiple phytohormones and expression of various genes. However, whether plant hormone brassinosteroid (BR) is involved in this process remains obscure. In this work, three genes that encode BR core signaling components brassinazole resistant (BZR) proteins, namely MaBZR1 to MaBZR3, were characterized from banana fruit. MaBZR1‐MaBZR3 exhibited both nuclear and cytoplasmic localization and behaved as transcription inhibitors. Expression analysis showed that MaBZR1/2/3 were continuously decreased as fruit ripening proceeded, indicating their negative roles in banana ripening. Moreover, gel shift and transient expression assays demonstrated that MaBZR1/2 could suppress the transcription of ethylene biosynthetic genes, including MaACS1, MaACO13 and MaACO14, which increased gradually during the banana ripening, via specifically binding to CGTGT/CG sequence in their promoters. Importantly, exogenous application of BRs promotes banana ripening, which is presumably due to the accelerated expression of MaACS1 and MaACO13/14, and consequently the ethylene production. Our study indicates that MaBZR1/2 act as transcriptional repressors of ethylene biosynthetic genes during banana fruit ripening. [ABSTRACT FROM AUTHOR]

Cytotoxicity and inflammation‐associated toxic responses could be induced by bacterial lipopolysaccharides (LPS) in vitro and in vivo, respectively. However, the mechanism involved in LPS‐induced cardiac malformation in prenatal fetus is still unknown. In this study, we demonstrated that LPS was induced in gut microbiota imbalance mice, and next, LPS exposure during gastrulation in the chick embryo increased the incidence of cardia bifida. Gene transfection and tissue transplantation trajectory indicated that LPS exposure restricted the cell migration of cardiac progenitors to primary heart field in gastrula chick embryos. In vitro explant allograft of GFP‐labeled anterior primitive streak demonstrated that LPS treatments could inhibit cell migration. A similar observation was also obtained from the cell migration assay of scratch wounds using primary culture of cardiomyocytes or H9c2 cells. In the embryos exposed to LPS, expressions of Nkx2.5 and GATA5 were disturbed. These genes are associated with cardiomyocyte differentiation when heart tube fusion occurs. Furthermore, pHIS3, C‐caspase3 immunohistological staining indicated that cell proliferation decreased, cell apoptosis increased in the heart tube of chick embryo. Meanwhile, in vivo, pHIS3 immunohistological staining and Hochest/PI staining also draw the similar conclusions. The LPS exposure also caused the production of excess ROS, which might damage the cardiac precursor cells of developing embryos. At last, we showed that LPS‐induced cardia bifida could be partially rescued through the addition of antioxidants. Together, these results reveal that excess ROS generation is involved in the LPS‐induced defects in heart tube during chick embryo development. Cytotoxicity and inflammation‐associated toxic responses could be induced by bacterial lipopolysaccharides (LPS) in vitro and in vivo, respectively. The LPS exposure also caused the production of excess ROS, which might damage the cardiac precursor cells of developing embryos. [ABSTRACT FROM AUTHOR]

Abstract: Two series of isostructural lanthanide coordination complexes, namely, LIFM‐42(Ln) (Ln=Eu, Tb, Gd, in which LIFM stands for the Lehn Institute of Functional Materials) and LIFM‐43(Ln) (Ln=Er, Yb), were synthesized through the self‐assembly of an excited‐state intramolecular proton transfer (ESIPT) ligand, 5‐[2‐(5‐fluoro‐2‐hydroxyphenyl)‐4,5‐bis(4‐fluorophenyl)‐1H‐imidazol‐1‐yl]isophthalic acid (H2hpi2cf), with different lanthanide ions. In the coordination structures linked by the ligands and oxo‐bridged LnIII2 clusters (for LIFM‐42(Ln) series) or isolated LnIII ions (for LIFM‐43(Ln) series), the ESIPT ligand can serve as both the host and antenna for protecting and sensitizing the photoluminescence (PL) of LnIII ions. Meanwhile, the −OH⋅⋅⋅N active sites on the ligands are vacant, which provides availability to systematically explore the PL behavior of Ln complexes with ESIPT interference. Based on the accepting levels of different lanthanide ions, energy transfer can occur from the T1(K*) or T1(E*) (K*=excited keto form, E*=excited enol form) excited states of the ligand. Furthermore, the sensitized lanthanide luminescence in both visible and near‐infrared regions, as well as the remaining K* emission of the ligand, can be modulated by the ESIPT responsiveness to different solvents, anions, and temperature. [ABSTRACT FROM AUTHOR]

Abstract: This paper provides a theoretical perspective of how modeling and simulation on a CAD platform can be used to teach science concepts and inform design decisions. The paper discusses the educational implications of three recent advancements in CAD technologies: system integration, machine learning, and computational design. The challenges to design energy‐efficient buildings that harness solar energy are used as the engineering examples to illustrate the learning and teaching opportunities created by the modeling, simulation, and data mining capabilities of the Energy3D software, which is a CAD tool developed from scratch along the directions of the three advancements to support engineering research and education. Preliminary results from students in a physics classroom and an online course shed light on the effects of these features on guiding student to design cost‐effective rooftop solar power systems for their own home buildings. [ABSTRACT FROM AUTHOR]

Abstract: In this work, we present a multiple amplified electrochemical method that can detect target microRNA‐21 (miRNA‐21) with high sensitivity by using hierarchical flower‐like gold nanostructures (HFGNs) and gold‐enriched enzyme‐free amplification. The HFGNs deposited on ITO conducting glass served as the electrode substrate with large specific surface area, which allowed the immobilization of large amounts of capture DNA (DNA‐1). Then, the gold‐enriched hybridization chain reaction (HCR) for signal amplification was attached onto the electrode through target miRNA‐mediated sandwich hybridization. The initial strands (I‐DNA) enriched on gold nanoparticles (AuNPs) provided plenty of sites for the triggering of the HCR reaction after the addition of H1 and H2 strands, which provided exponential increase of binding sites for the loading of electrochemical signal molecules [Ru(NH3)6]3+. Therefore, multiple signal amplification could be achieved to reach an ultrasensitive detection of miRNA‐21. A wide linear dynamic range from 1 fM to 1 nM and a detection limit of 0.12 fM (S/N=3) was reached with good selectivity. The electrochemical assay method in this work may hold a great potential for clinical diagnosis of genetic disease in the future. [ABSTRACT FROM AUTHOR]

As the first example of a photocatalytic system for splitting water without additional cocatalysts and photosensitizers, the comparatively cost-effective Cu2I2-based MOF, Cu-I-bpy (bpy=4,4′-bipyridine) exhibited highly efficient photocatalytic hydrogen production (7.09 mmol g−1 h−1). Density functional theory (DFT) calculations established the electronic structures of Cu-I-bpy with a narrow band gap of 2.05 eV, indicating its semiconductive behavior, which is consistent with the experimental value of 2.00 eV. The proposed mechanism demonstrates that Cu2I2 clusters of Cu-I-bpy serve as photoelectron generators to accelerate the copper(I) hydride interaction, providing redox reaction sites for hydrogen evolution. The highly stable cocatalyst-free and self-sensitized Cu-I-bpy provides new insights into the future design of cost-effective d10-based MOFs for highly efficient and long-term solar fuels production. [ABSTRACT FROM AUTHOR]

Aquaporin 4 ( AQP4) is a type of water channel protein that maintains the water balance of cardiomyocytes. However, the physiological role of AQP4 in cardiovascular disease is poorly understood. We wanted to explore whether p66Shc and endoplasmic reticulum stress participates in AQP4 knockout ( KO)-mediated cardiac injury. There were two types of mice: AQP4 knockout and wild-type mice. Each type was randomly divided into three groups: Control group, isoprenaline stimulation group ( ISO, 1 mg/kg, s.c., 5 days), and apocynin treatment group ( APO, 100 mg/kg, p.o., 3 days). H9c2 rat cardiomyocytes were cultured for RNA interference of AQP4. Results showed increased left ventricular weight index and more severe myocardial inflammation were induced in AQP4 knockout mice relative to wild-type mice, accompanied by significantly increased levels of the oxidative stress biomarkers MDA and NOX4. In addition, the expressions of p66Shc, ER stress markers PERK, GRP78 and CHOP and proinflammatory factors such as ETA, IL6 and TNFα were upregulated in the myocardium of AQP4 knockout mice or AQP4 si RNA treated cardiomyocytes, whereas CASQ2 was downregulated. ISO stimulation aggravated these abnormalities, which were significantly attenuated by apocynin. This study showed that AQP4 knockout mice were susceptible to cardiac injury induced by ISO. The mechanism was closely connected with p66Shc and proinflammatory factors. Endoplasmic reticulum stress was also involved in the pathological process. [ABSTRACT FROM AUTHOR]

Many pedagogical innovations aim to integrate engineering design and science learning. However, students frequently show little attempt or have difficulties in connecting their design projects with the underlying science. Drawing upon the Cultural-Historical Activity Theory, we argue that the design tools available in a learning environment implicitly shape knowledge development as they mediate students' design actions. To explore the roles of tools in design-science integrated learning environments, this study investigated how secondary students' tool-mediated design actions were linked with their science learning in a tool-rich design environment with minimal explicit guidance. Eighty-three ninth-grade students completed an energy-efficient home design challenge in a simulated environment for engineering design supported by rich design tools. Results showed that students substantially improved their knowledge as a result of designing with the tools. Further, their learning gains were positively associated with three types of design actions-representation, analysis, and reflection-measured by the cumulative counts of relevant computer logs. In addition, these design actions were linked with learning gains in ways that were consistent with their theoretical impacts on knowledge development. These findings suggest that, instead of being passive components in a learning environment, tools considerably shape design processes, and learning paths. As such, tools offer possibilities to help bridge the design-science gap. © 2017 The Authors. Journal of Research in Science Teaching Published by Wiley Periodicals, Inc. J Res Sci Teach 9999:1049-1096, 2017 [ABSTRACT FROM AUTHOR]

Plasmonic nanostructures with distinct spatial configuration and geometry are of considerable significance because of their desired optical response. These optical responses have close relationship with the inter-particle parameters in plasmonic nanostructures. However, the precise control of the consecutive variation of these parameters remains a formidable challenge. Here, we demonstrate a gold nanoparticle (AuNP) -based plasmonic nano-reporter, in which a AuNP performs as a walker to stepwise roll directionally and progressively on DNA origami. Using another AuNP as a stator, the rolling of the AuNP reporter could generate the inter-particle distance variation, which would be monitored by surface-enhanced Raman scattering (SERS). Our method opens up a door to develop an optical reporter that monitors inter-particle variations in plasmonic nanostructures. [ABSTRACT FROM AUTHOR]

OBJECTIVE To investigate serine protease inhibitor Kazal type 1 (SPINK1) expression and its influence on the prognosis of human hepatocellular carcinoma (HCC) and to explore the underlying molecular mechanisms involved. METHODS Altogether 80 patients with HCC who underwent curative resection were followed up for a median of 58.6 months. SPINK1 expression was detected in the primary HCC samples by immunohistochemistry. Its role in tumor invasion and metastasis was evaluated in vitro by gene silencing using a small interfering RNA-mediated approach, recombinant SPINK1 and U0126 (an inhibitor of MEK/ERK). The proteins in the MEK/ERK signaling pathway were detected by Western blot. RESULTS Patients with high SPINK1 expression showed poor overall survival ( P = 0.0001) and recurrence-free survival ( P = 0.001) compared with those with low SPINK1 expression. The suppression of SPINK1 resulted in reduced cell migration and invasion. SPINK1 overexpression was significantly associated with increased cell migration and invasion in vitro. Furthermore, SPINK 1 promoted cancer cells motility and epithelial-mesenchymal transition (EMT) via the mitogen-activated protein kinase kinase (MAPK) and extracellular regulated kinase (ERK) pathway, resulting in increased vimentin expression and decreased E-cadherin expression. CONCLUSION SPINK1 may be an oncogene that induces EMT via the MEK/ERK pathway and is a potential target for HCC therapy. [ABSTRACT FROM AUTHOR]

Numerical simulations of solidification process of steel ingots weighing 19, 8.5, and 3.35 ton are carried out and the calculated results are validated against temperature measurement during solidification of steel ingots. A new concept of 'effective transient thermal resistance' is proposed to help analyze heat transfer resistances of mold, ingot/mold interface, solidified shell, and outer wall of mold. Consequently, the restrictive steps of heat transfer (RSHT) at different stages of solidification of steel ingots are dug out. It is found that the RSHT during solidification of steel ingots weighing 19, 8.5, and 3.35 ton are similar. At early-stage of solidification, the effective transient thermal resistances of the mold and ingot/mold interface increase rapidly. Heat transfers through the mold and ingot/mold interface, are the RSHT. At mid-stage of solidification, the effective transient thermal resistance of the outer wall of the mold is larger than that of other heat transfer sections. Heat transfer section of the outer wall of mold is the RSHT. At late-stage of solidification, the heat transfer section of the solidified shell is the RSHT due to the thickening of the solidified shell. In addition, it was found that variations of pouring temperature and mold's thickness do not change the RSHT during solidification of steel ingots. [ABSTRACT FROM AUTHOR]

DNA hydrogels hold great potential for biological and biomedical applications owing to their programmable nature and macroscopic sizes. However, most previous studies involve spontaneous and homogenous gelation procedures in solution, which often lack precise control. A clamped hybridization chain reaction (C-HCR)-based strategy has been developed to guide DNA self-assembly to form macroscopic hydrogels. Analogous to catalysts in chemical synthesis or seeds in crystal growth, we introduced DNA initiators to induce the gelation process, including crosslinked self-assembly and clamped hybridization in three dimensions with spatial and temporal control. The formed hydrogels show superior mechanical properties. The use of printed, surface-confined DNA initiators was also demonstrated for fabricating 2D hydrogel patterns without relying on external confinements. This simple method can be used to construct DNA hydrogels with defined geometry, composition, and order for various bioapplications. [ABSTRACT FROM AUTHOR]

DNA-based machines have attracted rapidly growing interest owing to their potential in drug delivery, biocomputing, and diagnostic applications. Herein, we report a type of exonuclease III (Exo III)-powered stochastic DNA walker that can autonomously move on a spherical nucleic acid (SNA)-based 3D track. The motion is propelled by unidirectional Exo III digestion of hybridized DNA tracks in a burnt-bridge mechanism. The operation of this Exo III-propelled DNA walker was monitored in real time and at the single-particle resolution using total internal reflection fluorescence microscopy (TIRF). We further interrogated the morphological effect of the 3D track on the nuclease activity, which suggested that the performance of the DNA walker was critically dependent upon the DNA density and the track conformation. Finally, we demonstrated potential bioanalytical applications of this SNA-based stochastic DNA walker by exploiting movement-triggered cascade signal amplification. [ABSTRACT FROM AUTHOR]

The precise functionalization of self-assembled nanostructures with spatial and stereocontrol is a major objective of nanotechnology and holds great promise for many applications. Herein, the nanoscale addressability of DNA origami was exploited to develop a precise copymachine- like platform that can transfer two-dimensional oligonucleotide patterns onto the surface of gold nanoparticles (AuNPs) through a deliberately designed toehold-initiated DNA displacement reaction. This strategy of DNA-origamibased nanoimprinting lithography (DONIL) demonstrates high precision in controlling the valence and valence angles of AuNPs. These DNA-decorated AuNPs act as precursors in the construction of discrete AuNP clusters with desired chirality. [ABSTRACT FROM AUTHOR]

Baeckea frutescens is an aromatic shrub used as ornamentals and as food flavor spices in the southern part of P. R. China. Two novel C-methylated biflavonoids named baeckeins J ( 1) and K ( 2) were isolated from the roots of B. frutescens, which possessed the unique carbon skeleton conjugated of a flavonol and one isoflavanonol molecule via the linkages of C(2)-C(8*) and C(3)-O-C(7*). The structures of compounds 1 and 2 were elucidated by analysis of 1D- and 2D-NMR, and HR-ESI-MS spectral data, and the absolute configuration for chiral C-atoms C(2) and C(3) were assigned by CD spectrometry combined with quantum chemical calculations. In the bioassay, baeckeins J and K exhibited strong cytoprotective effects on H2O2-induced oxidative cell death in PC12 cells. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) layered nanomaterials, e.g. graphene and molybdenum disulfide (MoS2), have rapidly emerged in material sciences due to their unique physical, chemical and mechanical properties. In the meanwhile, there is a growing interest in constructing electrochemical sensors for a wide range of chemical and biological molecules by using these 2D nanomaterials. In this review, we summarize recent advances on using graphene and MoS2 for the development of electrochemical sensors for small molecules, proteins, nucleic acids and cells detection. We also provide our perspectives in this rapidly developing field. [ABSTRACT FROM AUTHOR]

DNA nanostructures have found widespread applications in areas including nanoelectronics and biomedicine. However, traditional DNA origami needs a long single-stranded virus DNA and hundreds of short DNA strands, which make this method complicated and money-consuming. Here, we present a protocol for the assembly of DNA nanoribbons with only four oligonucleotides. DNA nanoribbons with different dimensions were successfully assembled with a 96-base scafford strand and three short staples. These biotinylated nanoribbons could also be decorated with streptavidins. This approach suggests that there exist great design spaces for the creation of simple nucleic acid nanostructures which could facilitate their application in plasmonic or drug delivery. [ABSTRACT FROM AUTHOR]