DNA nanomachines reveal an adaptive energy mode in confinement-induced amoeboid migration powered by polarized mitochondrial distribution.

Energy metabolism is highly interdependent with adaptive cell migration in vivo. Mechanical confinement is a critical physical cue that induces switchable migration modes of the mesenchymal-to-amoeboid transition (MAT). However, the energy states in distinct migration modes, especially amoeboid-like stable bleb (A2) movement, remain unclear. In this report, we developed multivalent DNA framework-based nanomachines to explore strategical mitochondrial trafficking and differential ATP levels during cell migration in mechanically heterogeneous microenvironments. Through single-particle tracking and metabolomic analysis, we revealed that fast A2-moving cells driven by biomimetic confinement recruited back-end positioning of mitochondria for powering highly polarized cytoskeletal networks, preferentially adopting an energy-saving mode compared with a mesenchymal mode of cell migration. We present a versatile DNA nanotool for cellular energy exploration and highlight that adaptive energy strategies coordinately support switchable migration modes for facilitating efficient metastatic escape, offering a unique perspective for therapeutic interventions in cancer metastasis.

Expanding DNA Origami Design Freedom with De Novo Synthesized Scaffolds.

The construction of DNA origami nanostructures is heavily dependent on the folding of the scaffold strand, which is typically a single-stranded DNA genome extracted from a bacteriophage (M13). Custom scaffolds can be prepared in a number of methods, but they are not widely accessible to a broad user base in the DNA nanotechnology community. Here, we explored new design and construction possibilities with custom scaffolds prepared in our cost- and time-efficient production pipeline. According to the pipeline, we de novo produced a variety of scaffolds of specified local and global sequence characteristics and consequent origami constructs of modular arrangement in morphologies and functionalities. Taking advantage of this strategy of template-free scaffold production, we also designed and produced three-letter-coded scaffolds that can fold into designated morphologies rapidly at room temperature. The expanded design and construction freedom immediately brings in many new research opportunities and invites many more on the horizon.

The association between visceral fat obesity and prefrailty in Chinese older adults: a cross-sectional study.

BACKGROUND: The prevalence of obesity is escalating. Previous research has concentrated on the link between frailty and obesity; however, the association between prefrailty and obesity has been less studied. Prefrailty screening and intervention may prevent or postpone frailty in older persons. OBJECTIVE: The study was to investigate into the relationship between prefrailty and several obesity indicators in Chinese community-dwelling older individuals. METHODS: This research employed the Frailty Screening Index to investigate the frailty phenotype of people living in Shanghai. Bioelectrical impedance analysis was used for evaluating body composition. RESULTS: There were 510 participants (39.0%) with high visceral adipose areas. Participants with a high visceral adipose area showed a higher risk of prefrailty (adjusted OR, 1.53; 95% CI, 1.19-1.96), according to multivariate models. When body mass index (BMI) and visceral fat area (VFA) were combined, it was discovered that having an overweight BMI with normal VFA was a protective factor for prefrailty (corrected OR, 0.62; 95% CI, 0.43-0.90), but having a normal weight but excess VFA increased the risk of prefrailty (corrected OR, 1.87; 95% CI, 1.15-3.03). CONCLUSION: Visceral fat obesity is an independent risk factor for prefrailty in Chinese older adults. Implementing targeted interventions, such as dietary modifications, increased physical activity, and other lifestyle changes, could play a crucial role in reducing the risk of prefrailty and improving overall health outcomes in this population.

Engineering of Multivalent Membrane-Anchored DNA Frameworks for Precise Profiling of Variable Membrane Permeability During Reversible Electroporation.

Electroporation techniques have emerged as attractive tools for intracellular delivery, rendering promising prospects towards clinical therapies. Transient disruption of membrane permeability is the critical process for efficient electroporation-based cargo delivery. However, smart nanotools for precise characterization of transient membrane changes induced by strong electric pulses are extremely limited. Herein, multivalent membrane-anchored fluorescent nanoprobes (MMFNPs) that take advantages of flexible functionalization and spatial arrangement of DNA frameworks are developed for in situ evaluation of electric field-induced membrane permeability during reversible electroporation . Single-molecule fluorescence imaging techniques are adopted to precisely  verify the excellent analytical performance of the engineered MMFNPs. Benefited from tight membrane anchoring and sensitive adenosine triphosphate (ATP) profiling, varying degrees of membrane disturbances are visually exhibited under different intensities of the microsecond pulse electric field (µsPEF). Significantly, the dynamic process of membrane repair during reversible electroporation is well demonstrated via ATP fluctuations monitored by the designed MMFNPs. Furthermore, molecular dynamics (MD) simulations are performed for accurate verification of electroporation-driven dynamic cargo entry via membrane nanopores. This work provides an avenue for effectively capturing transient fluctuations of membrane permeability under external stimuli, offering valuable guidance for developing efficient and safe electroporation-driven delivery strategies for clinical diagnosis and therapeutics.