DNA Reaction Circuits to Establish Designated Biological Functions in Multicellular Community.

In multicellular organisms, individual cells are coordinated through complex communication networks to accomplish various physiological tasks. Aiming to establish new biological functions in the multicellular community, we used DNA as the building block to develop a cascade of nongenetic reaction circuits to establish a dynamic cell-cell communication network. Utilizing membrane-anchored amphiphilic DNA tetrahedra (TDN) as the nanoscaffold, reaction circuits were incorporated into three unrelated cells in order to uniquely regulate their sense-and-response behaviors. As a proof-of-concept, this step enabled these cells to simulate significant biological events involved in T cell-mediated anticancer immunity. Such events included cancer-associated antigen recognition and the presentation of antigen-presenting cells (APCs), APC-facilitated T cell activation and dissociation, and T cell-mediated cancer targeting and killing. By combining the excellent programmability and molecular recognition ability of DNA, our cell-surface reaction circuits hold promise for mimicking and manipulating many biological processes.

Domain-Targeted Membrane Partitioning of Specific Proteins with DNA Nanodevices.

The cell membrane exhibits a remarkable complexity of lipids and proteins that dynamically segregate into distinct domains to coordinate various cellular functions. The ability to manipulate the partitioning of specific membrane proteins without involving genetic modification is essential for decoding various cellular processes but highly challenging. In this work, by conjugating cholesterols or tocopherols at the three bottom vertices of the DNA tetrahedron, we develop two sets of nanodevices for the selective targeting of lipid-order (Lo) and lipid-disorder (Ld) domains on the live cell membrane. By incorporation of protein-recognition ligands, such as aptamers or antibodies, through toehold-mediated strand displacement, these DNA nanodevices enable dynamic translocation of target proteins between these two domains. We first used PTK7 as a protein model and demonstrated, for the first time, that the accumulation of PTK7 to the Lo domains could promote tumor cell migration, while sequestering it in the Ld domains would inhibit the movement of the cells. Next, based on their modular nature, these DNA nanodevices were extended to regulate the process of T cell activation through manipulating the translocation of CD45 between the Lo and the Ld domains. Thus, our work is expected to provide deep insight into the study of membrane structure and molecular interactions within diverse cell signaling processes.

Aptamer-Based Multiparameter Analysis for Molecular Profiling of Hematological Malignancies.

The subtypes of hematological malignancies (HM) with minimal molecular profile differences display an extremely heterogeneous clinical course and a discrepant response to certain treatment regimens. Profiling the surface protein markers offers a potent solution for precision diagnosis of HM by differentiating among the subtypes of cancer cells. Herein, we report the use of Cell-SELEX technology to generate a panel of high-affinity aptamer probes that are able to discriminate subtle differences among surface protein profiles between different HM cells. Experimental results show that these aptamers with apparent dissociation constants (Kd) below 10 nM display a unique recognition pattern on different HM subtypes. By combining a machine learning model on the basis of partial least-squares discriminant analysis, 100% accuracy was achieved for the classification of different HM cells. Furthermore, we preliminarily validated the effectiveness of the aptamer-based multiparameter analysis strategy from a clinical perspective by accurately classifying complex clinical samples, thus providing a promising molecular tool for precise HM phenotyping.

Iron-doped carbon nanotubes with magnetic enhanced Fe(VI) degradation of arsanilic acid and inorganic arsenic: Role of intermediate iron species and electron transfer.

Arsanilic acid (p-AsA), a prevalently used feed additive, is frequently detected in environment posing a great threat to humans. Potassium ferrate (Fe(VI)) was an efficient way to tackle arsenic contamination under acid and neutral conditions. However, Fe(VI) showed a noneffective removal of p-AsA under alkaline conditions due to its oxidation capacity attenuation. Herein, a magnetic iron-doped carbon nanotubes (F-CNT) was successfully prepared and further catalyzed Fe(VI) to remove p-AsA and total As species. The Fe(VI)/F-CNT system showed an excellent capability to oxidize p-AsA and adsorb total As species over an environment-related pH range of 6-9. The high-valent iron intermediates Fe(V)/Fe(IV) and the mediated electron-transfer played a significant part in the degradation of p-AsA according to the probes/scavengers experiments and galvanic oxidation process. Moreover, the situ formed iron hydroxide oxide and F-CNT significantly improved the adsorption capacity for total As species. The electron-donating groups (semiquinone and hydroquinone) and high graphitization of F-CNT were responsible for activating Fe(VI) based on the analysis of X-ray photoelectron spectroscopy (XPS). Density functional theory calculations and the detected degradation products both indicated that the amino group and the C-As bond of p-AsA were main reactive sites. Notably, Fe(VI)/F-CNT system was resistant to the interference from Cl-, SO42-, and HCO3-, and could effectively remove p-AsA and total As species even in the presence of complex water matrix. In summary, this work proposed an efficient method to use Fe(VI) for degrading pollutants under alkaline conditions and explore a new technology for livestock wastewater advanced treatment.

Collaborative management of environmental pollution and carbon emissions drives local green growth: An analysis based on spatial effects.

Collaborative management of environmental pollution and carbon emissions (CMPC) has been a major policy instrument to promote Sustainable Development Goals (SDG) in recent years. However, the relationship between the benefits and drawbacks of this environmental management practice for green growth in and around a local area remains to be clarified. Using 30 provinces in China during 2001-2019 as the object of analysis, we assessed the efficiency of local CMPC practices using the nonradial directional distance function (NDDF) model, predicted local green growth using the frontier green complexity index (GCI), and empirically examined the spatial effects, locational heterogeneity, and threshold characteristics of the relationship using the spatial Durbin model and the panel threshold model. Our study finds that although efficient CMPC does drive local green growth, the promotion effect is nonlinear with decreasing marginal effect. This effect is particularly obvious in economically developed regions with higher CMPCs, which will absorb resources from neighboring regions and create a "siphoning" effect. It was found that local financial support and foreign direct investment (FDI) can radiate green growth to neighboring regions; therefore, CMPC practice needs to pay more attention to the effect of joint governance, supplemented by financial and foreign investment policy tools, to better promote the green transformation of local economy.

Development and validation of models for predicting preterm birth and gestational latency following emergency cervical cerclage: A multicenter cohort study.

INTRODUCTION: Emergency cervical cerclage is a recognized method for preventing mid-trimester pregnancy loss and premature birth; however, its benefits remain controversial. This study aimed to establish preoperative models predicting preterm birth and gestational latency following emergency cervical cerclage in singleton pregnant patients with a high risk of preterm birth. MATERIAL AND METHODS: We retrospectively reviewed data from patients who received emergency cerclage between 2015 and 2023 in three institutions. Patients were grouped into a derivation cohort (n = 141) and an independent validation cohort (n = 61). Univariate and multivariate logistic and Cox regression analyses were used to identify independent predictive variables and establish the models. Harrell's C-index, time-dependent receiver operating characteristic curves and areas under the curves, calibration curve, and decision curve analyses were performed to assess the models. RESULTS: The models incorporated gestational weeks at cerclage placement, history of prior second-trimester loss and/or preterm birth, cervical dilation, and preoperative C-reactive protein level. The C-index of the model for predicting preterm birth before 28 weeks was 0.87 (95% CI: 0.82-0.93) in the derivation cohort and 0.82 (95% CI: 0.71-0.92) in the independent validation cohort; The C-index of the model for predicting gestational latency was 0.70 (95% CI: 0.66-0.75) and 0.78 (95% CI: 0.71-0.84), respectively. In the derivation set, the areas under the curves were 0.84, 0.81, and 0.84 for predicting 1-, 3- and 5-week pregnancy prolongation, respectively. The corresponding values for the external validation were 0.78, 0.78, and 0.79, respectively. Calibration curves showed a good homogeneity between the observed and predicted ongoing pregnant probabilities. Decision curve analyses revealed satisfactory clinical usefulness. CONCLUSIONS: These novel models provide reliable and valuable prognostic predictions for patients undergoing emergency cerclage. The models can assist clinicians and patients in making personalized clinical decisions before opting for the cervical cerclage.

A General Copper Catalytic System for Suzuki-Miyaura Cross-Coupling of Unactivated Secondary and Primary Alkyl Halides with Arylborons.

Suzuki-Miyaura cross-couplings (SMC) are powerful tools for the construction of carbon-carbon bonds. However, the couplings of sp3-hybridized alkyl halides with arylborons often encounter several problematic issues such as sluggish oxidation addition of alkyl halides and competitive ß-hydride elimination side pathways of metal-alkyl species. In precedent reports, copper is mainly utilized for the coupling of sp2-aryl halides, and the cross-couplings with unactivated alkyl halides are far less reported. Herein, we demonstrate that a high-efficiency copper system enabled the coupling of arylborons with various unactivated secondary and primary alkyl halides including bromides, iodides, and even robust chlorides. The present system features broad scope, excellent functionality tolerance, scalability, and practicality. Moreover, the current system could be applied for the late-stage functionalization of complex molecules in moderate to high efficiency.

Chemically Synthetic Membrane Receptors Establish Cells with Artificial Sense-and-Respond Signaling Pathways.

Chemically synthetic receptors that establish cells a new sense-and-respond capability to interact with outer worlds are highly desired, but rarely reported. In this work, we develop a membrane-anchored synthetic receptor (Ts-pHLIP-Pr) using DNA and peptide as the building block to equip cells with artificial signaling pathways. Upon sensing external pH stimuli, the Pr module can be translocated across the cell membrane via the conformation switch of pHLIP, enabling membrane-proximal recruitment of specific proteins to trigger downstream signaling cascades. Our experimental results demonstrate the capability of Ts-pHLIP-Pr for regulating PKCε-related signaling events upon responding to external pH reduction. With a modular feature, this receptor can be extended to elicit T cell activation through low-pH environment-induced directional movement of cytoplasmic ZAP70. Our work is expected to offer a new paradigm for intelligent synthetic biology and customized cell engineering.

Aptamer-Based Targeted Delivery of Functional Nucleic Acids.

Functional nucleic acid (NA)-based drugs have a broad range of applications since they allow the alteration and control of gene/protein expression patterns in cells. In principle, functional NAs need to be transported precisely and efficiently to target cells to guarantee both functionality and safety. Owing to their negative charges, it is difficult for natural NAs to cross the cell membrane composed of lipid bilayer and enter targeted cells. Worse still, the delivery of undirected functional NAs to nontargeted healthy cells and/or tissues would induce unpredictable adverse effects. Therefore, the precisely targeted delivery of functional NAs to specific cells/organs, particularly in extrahepatic sites, is required. Since aptamers can bind to various proteins on the cell surface with high specificity and selectivity, they can serve as the molecular recognition units to accurately bind target cells and subsequently enable the efficient delivery of cargo. In this perspective, we summarize the original, proof-of-concept aptamer-based strategies for the targeted delivery of functional NAs. A few specific examples are then discussed, followed by our perspectives on some of the challenges and opportunities that lie ahead.

Nondestructive and Quantitative Analysis of Cell Wall Regeneration in the Medicinal Macrofungus Ganoderma lingzhi by a Membrane-Fusing Fluorescent Probe.

Ganoderma is a prize medicinal macrofungus with a broad range of pharmaceutical values. To date, various attempts have been made to cultivate Ganoderma to improve the production of secondary metabolites with pharmacological activity. Among the adopted techniques, protoplast preparation and regeneration are indispensable. However, the evaluation of protoplasts and regenerated cell walls usually relies on electron microscopy assays, which require time-consuming and destructive sample preparation and merely provide localized information in the selected area. In contrast, fluorescence assays enable sensitive real-time detection and imaging in vivo. They can also be applied to flow cytometry, providing a collective overview of every cell in a sample. However, for macrofungi such as Ganoderma, the fluorescence analysis of protoplasts and regenerated cell walls is difficult owing to the hindrance of the homologous fluorescent protein expression and the lack of an appropriate fluorescence marker. Herein, a specific plasma membrane probe, TAMRA perfluorocarbon nucleic acid probe (TPFN), is proposed for the nondestructive and quantitative fluorescence analysis of cell wall regeneration. Exploiting the perfluorocarbon membrane-anchoring chains, hydrophilic nucleic acid linker, and fluorescent dye TAMRA, the probe is proven to be selective, soluble, and stable, enabling rapid fluorescence detection of a protoplast sample free of transgenic expression or immune staining. Based on the TPFN and flow cytometry techniques, a quantitative approach is constructed to monitor the process of cell wall growth in a fast, quantitative, and high-throughout manner, and the obtained results are consistent with those of conventional electron microscopy. In principle, with slight modifications or integration, the proposed probe and approach can be adapted to the preparation of cell protoplasts, inspection of cell wall integrity under environmental stress, and programmable membrane engineering for cytobiology and physiology research.

Artificial Nucleotide Aptamer-Based Field-Effect Transistor for Ultrasensitive Detection of Hepatoma Exosomes.

An aptamer-based field-effect transistor (Apta-FET) is a well-developed assay method with high selectivity and sensitivity. Due to the limited information density that natural nucleotide library holds, the Apta-FET faces fundamental restriction in universality to detect various types of analytes. Herein, we demonstrate a type of Apta-FET sensors based on an artificial nucleotide aptamer (AN-Apta-FET). The introduction of an artificial nucleotide increases the diversity of the potential aptamer structure and expands the analyte category of the Apta-FET. The AN-Apta-FET specifically detects hepatoma exosomes, which traditional Apta-FET fails to discriminate from other tumor-derived exosomes, with a limit of detection down to 242 particles mL-1. The AN-Apta-FET distinguishes serum samples of hepatocellular carcinoma patients within 9 min from those of healthy people, showing the potential as a comprehensive assay tool in future disease diagnosis.

Leguminous plants significantly increase soil nitrogen cycling across global climates and ecosystem types.

Leguminous plants are an important component of terrestrial ecosystems and significantly increase soil nitrogen (N) cycling and availability, which affects productivity in most ecosystems. Clarifying whether the effects of legumes on N cycling vary with contrasting ecosystem types and climatic regions is crucial for understanding and predicting ecosystem processes, but these effects are currently unknown. By conducting a global meta-analysis, we revealed that legumes increased the soil net N mineralization rate (Rmin ) by 67%, which was greater than the recently reported increase associated with N deposition (25%). This effect was similar for tropical (53%) and temperate regions (81%) but was significantly greater in grasslands (151%) and forests (74%) than in croplands (-3%) and was greater in in situ incubation (101%) or short-term experiments (112%) than in laboratory incubation (55%) or long-term experiments (37%). Legumes significantly influenced the dependence of Rmin on N fertilization and experimental factors. The Rmin was significantly increased by N fertilization in the nonlegume soils, but not in the legume soils. In addition, the effects of mean annual temperature, soil nutrients and experimental duration on Rmin were smaller in the legume soils than in the nonlegume soils. Collectively, our results highlighted the significant positive effects of legumes on soil N cycling, and indicated that the effects of legumes should be elucidated when addressing the response of soils to plants.

Association of SARS-CoV-2 viral load with abnormal laboratory characteristics and clinical outcomes in hospitalised COVID-19 patients.

We conducted a retrospective, analytical cross-sectional and single-centre study that included 190 hospitalised COVID-19 patients in the Fujian Provincial Hospital South Branch between December 2022 and January 2023 to analyse the correlation of viral loads of throat swabs with clinical progression and outcomes. To normalise the Ct value as quantification of viral loads, we used RNase P gene as internal control gene and subtracted the Ct value of SARS-CoV-2 N gene from the Ct value of RNase P gene, termed △Ct. Most patients were discharged (84.2%), and only 10 (5.6%) individuals who had a lower △Ct value died. The initial △Ct value of participants was also significantly correlated with some abnormal laboratory characteristics, and the duration time of SARS-CoV-2 was longer in patients with severe symptoms and a lower △Ct value at admission. Our study suggested that the △Ct value may be used as a predictor of disease progression and outcomes in hospitalised COVID-19 patients.

Responses of bacterial and three sub-microeukaryote communities in the water of white shrimp Penaeus vannamei aquaculture ponds in two polyculture models.

Polyculture operations in freshwater aquaculture ponds can disrupt microbial communities. High-throughput sequencing was used to assess the impact of polyculture operations on bacterial and three sub-microeukaryote communities (fungi, zooplankton, and eukaryotic phytoplankton) in Penaeus vannamei aquaculture ponds containing oriental river prawns and giant freshwater prawns, respectively. The results showed that the bacterial community was less sensitive than the microeukaryote communities to both the polyculture activity and environmental variations. The polyculture of giant freshwater prawns rather than oriental river prawns was the primary factor affecting the beta diversity of the three sub-microeukaryote communities. This may be due to the larger biomass of the polyculture varieties of giant freshwater prawns compared with oriental river prawns. The polyculture activity of giant freshwater prawns with a higher density and that of oriental river prawns with a lower density increased the stochasticity of the community assembly of the three sub-microeukaryote communities. It also affected the topological properties of the microbial communities, including greater correlations between ecosystem elements, and reducing the correlations among zooplanktons. The eukaryotic phytoplankton was the only microbial community that could also be explained by nutrient variation (mainly the total nitrogen). This highlights the potential role of the eukaryotic phytoplankton as a suitable indicator of the effects of nutrient input into ecosystems.

Aptamer-Functionalized Nanodevices for Dynamic Manipulation of Membrane Receptor Signaling in Living Cells.

The capacity to regulate the signaling amplitude of membrane receptors in a user-defined manner would open various opportunities for precise biological study and therapy. While partial agonists enabled downtuning of cellular responses, they required esoteric optimization of the ligand-receptor interface, limiting their practical applications. Herein, we developed an aptamer-functionalized, tweezer-like nanodevice to dynamically modulate the cellular behavior through control over the distance between receptors in the dimer with no need to involve complicated structural analysis. By combining a reversible conformation switch with aptamer-based molecular recognition, this nanodevice showed excellent performance on dynamic regulation of CD28 receptor-mediated T cell immunity. With the modular design, this nanodevice could be extended to dynamically modulate the activity of other membrane receptors (e.g., c-Met), expecting to offer a new paradigm for precise study and manipulation of specific molecular events in complex biological systems.

An Aptamer-Functionalized DNA Circuit to Establish an Artificial Interaction between T Cells and Cancer Cells.

Nongenetic strategies that enable control over the cell-cell interaction network would be highly desired, particularly in T cell-based cancer immunotherapy. In this work, we developed an aptamer-functionalized DNA circuit to modulate the interaction between T cells and cancer cells. This DNA circuit was composed of recognition-then-triggering and aggregation-then-activation modules. Upon recognizing target cancer cells, the triggering strand was released to induce aggregation of immune receptors on the T cell surface, leading to an enhancement of T cell activity for effective cancer eradication. Our results demonstrated the feasibility of this DNA circuit for promoting target cancer cell-directed stimulation of T cells, which, consequently, enhanced their killing effect on cancer cells. This DNA circuit, as a modular strategy to modulate intercellular interactions, could lead to a new paradigm for the development of nongenetic T cell-based immunotherapy.

Aptamer-Based Analysis and Manipulation of the Protein Activity in Living Cells.

Directly analyzing and precisely manipulating the activity of target proteins without altering their natural structure and expression would be essential to decoding many protein-dominant cellular processes. To meet this goal, we used streptavidin as the carrier to develop an aptamer-based nanoplatform for monitoring the activation process of specific proteins in living cells. Our results showed that this nanoplatform could efficiently enter the cellular cytoplasm and specifically report the presence of RelA in the activated state. Meanwhile, with incorporation of a photoresponsive module, this aptamer-based nanoplatform was able to manipulate the nuclear translocation behavior of active RelA, enabling control over related downstream signaling events.

Afforestation can lower microbial diversity and functionality in deep soil layers in a semiarid region.

Afforestation is an effective approach to rehabilitate degraded ecosystems, but often depletes deep soil moisture. Presently, it is not known how an afforestation-induced decrease in moisture affects soil microbial community and functionality, hindering our ability to understand the sustainability of the rehabilitated ecosystems. To address this issue, we examined the impacts of 20 years of afforestation on soil bacterial community, co-occurrence pattern, and functionalities along vertical profile (0-500 cm depth) in a semiarid region of China's Loess Plateau. We showed that the effects of afforestation with a deep-rooted legume tree on cropland were greater in deep than that of in top layers, resulting in decreased bacterial beta diversity, more responsive bacterial taxa and functional groups, increased homogeneous selection, and decreased network robustness in deep soils (120-500 cm). Organic carbon and nitrogen decomposition rates and multifunctionality also significantly decreased by afforestation, and microbial carbon limitation significantly increased in deep soils. Moreover, changes in microbial community and functionality in deep layer was largely related to changes in soil moisture. Such negative impacts on deep soils should be fully considered for assessing afforestation's eco-environment effects and for the sustainability of ecosystems because deep soils have important influence on forest ecosystems in semiarid and arid climates.

The clinicopathological and prognostic value of CXCR4 expression in patients with lung cancer: a meta-analysis.

BACKGROUND: The C-X-C chemokine receptor 4 (CXCR4) has been suggested to play an important role in several types of cancers and is related to biological behaviors connected with tumor progression. However, the clinical significance and application of CXCR4 in lung cancer remain disputable. Thus, we conducted a meta-analysis to investigate the impact of CXCR4 expression on survival and clinicopathological features in lung cancer. METHODS: Comprehensive literature searches were conducted in PubMed, Embase and Web of Science for relevant studies. We pooled hazard ratios (HRs)/odds ratios (ORs) with 95% confidence intervals (CIs) by STATA 12.0 to evaluate the potential value of CXCR4 expression. RESULTS: Twenty-seven relevant articles involving 2932 patients with lung cancer were included in our meta-analysis. The results revealed that CXCR4 expression was apparently associated with poor overall survival (OS) (HR 1.61, 95% CI 1.42-1.82) and disease-free survival (HR 3.39, 95% CI 2.38-4.83). Furthermore, a significant correlation with poor OS was obvious in non-small cell lung cancer patients (HR 1.59, 95% CI 1.40-1.81) and in patients showing CXCR4 expression in the cytoplasm (HR 2.10, 95% CI 1.55-2.84) and the membrane (HR 1.74, 95% CI 1.24-2.45). CXCR4 expression was significantly associated with men (OR 1.32, 95% CI 1.08-1.61), advanced tumor stages (T3-T4) (OR 2.34, 95% CI 1.28-4.28), advanced nodal stages (N > 0) (OR 2.34, 95% CI 1.90-2.90), distant metastasis (OR 3.65, 95% CI 1.53-8.69), advanced TNM stages (TNM stages III, IV) (OR 3.10, 95% CI 1.95-4.93) and epidermal growth factor receptor (EGFR) expression (OR 2.44, 95% CI 1.44-4.12) but was not associated with age, smoking history, histopathology, differentiation, lymphatic vessel invasion or local recurrence. CONCLUSION: High expression of CXCR4 is related to tumor progression and might be an adverse prognostic factor for lung cancer.

DNA Nanostructure-Programmed Cell Entry via Corner Angle-Mediated Molecular Interaction with Membrane Receptors.

Despite its polyanionic nature, DNA can cross the negatively charged membrane to enter living cells by assembling into specific nanostructures, establishing various opportunities for biomedical applications. Mechanistic studies to explain how the geometrical parameters of DNA nanostructures impact the cell entry are critical but elusive. Here, we use experimentation and simulation to study the interaction between cells and three typical framework nucleic acids (FNAs), including tetrahedron, triangular prism, and cube. Different cellular uptake efficiency was observed among these FNAs, and similar distinction consistently existed in multiple cell lines. Scavenger receptors (SRs) were demonstrated to be essential in mediating the uptake process. Molecular docking simulations revealed that the SR binding predominantly depended on the corner angle of FNAs, determining cellular internalization frequency. This study clearly explains how FNAs interact with the membrane to initiate cell entry, offering new clues for the design of theranostic nanocarriers and the study of virus invasion.