Hexapoda comprises the hyperdiverse insects and three cryptic, early-diverging lineages, Protura, Collembola, and Diplura, that are key to understanding the hexapod body pattern but remain extremely rare as fossils. Here, we report the earliest dipluran, Sinojapyx giganteus gen. et sp. nov., from the Middle Jurassic Daohugou Biota (approx. 165 Mya). Its ectognathous mouthparts challenge the conventional view that all non‑insect hexapods are entognathous, providing solid evidence that entognathy evolved independently at least three times. The pincer‑like cerci of Sinojapyx are symmetrical and lack denticles, representing a transitional state preceding the sophisticated predatory appendages of extant japygoids. Exceeding 5 cm in body length and equipped with robust mandibles and pincer-like cerci, this giant soil dweller occupied the apex of the soil food web in the Jurassic, filling a niche typically held by scorpions or centipedes today. This discovery not only bridges a major gap in the dipluran fossil record but also offers critical insights into the ancestral body pattern of non‑insect hexapods and soil trophic networks in the Jurassic.

The left atrial appendage (LAA) is nowadays recognized as both an arrhythmogenic substrate and the dominant source of thromboembolism in atrial fibrillation (AF). In this review we tried to summarize recent data on the anatomy, physiology, and imaging of the LAA, and examine how these findings help guide rhythm-control and stroke-prevention strategies.

Atrial fibrillation (AF) develops through the interplay of electrical, structural, inflammatory, and metabolic remodeling. However, the circadian-associated molecular characteristics of the diseased human atrium remain incompletely understood.

In Harry Potter and the Chamber of Secrets, Professor Lockhart's inept attempt to heal Harry's broken arm with a spell instead removes all the bones in Harry's arm, leaving a useless floppy arm in its place. While a night of the potion Skele-Gro eventually regrows Harry's bones, this episode neatly highlights the critical role a rigid skeletal support structure plays in our ability to move. Without one, we are stuck. Yet some of the most dexterous and impressive examples of movement in the animal kingdom do so without such rigid support structure. Tongues, tentacles, and trunks, as memorably framed in a seminal paper by William Kier and Kathleen Smith, are in a unique class of appendages known as muscular hydrostats that include octopus arms, elephant trunks, squid tentacles, and many animal tongues (Figure 1). These appendages lack bones or other rigid support entirely and instead consist only of soft tissue such as muscle and connective tissue.

Atrial remodeling in atrial fibrillation (AF) involves multiple biological processes, including metabolic alterations, inflammation-related metabolic activity, and fibroblast activation, which can be assessed non-invasively with [18]F-fluorodeoxyglucose (FDG) and fibroblast activation protein inhibitors (FAPI) PET, respectively. We aimed to characterize and compare the atrial uptake patterns of these two tracers in patients with AF. In this post hoc cardinality-matched analysis of two prospective PET/CT cohorts, 90 patients with AF were included (45 imaged with [18]F-FDG and 45 with [18]F-FAPI). Left atrial volume index (LAVI) was measured using the echocardiographic ellipsoid method. The prevalence, intensity, and spatial distribution of atrial tracer uptake were compared between tracers, and clinical correlates of abnormal uptake were assessed using univariable analyses and logistic regression. [18]F-FAPI showed a higher left atrial (LA) target-to-background ratio than [18]F-FDG (P = 0.007). Abnormal uptake was more frequent with [18]F-FDG in the left atrial appendage (LAA; 83.3% vs. 23.1%, P < 0.001), and more frequent with [18]F-FAPI in the LA anterior wall (84.6% vs. 38.9%, P = 0.002) and LA roof (69.2% vs. 33.3%, P = 0.019). These differences persisted in persistent AF (PsAF); in paroxysmal AF, only the higher LAA [18]F-FDG uptake remained (P = 0.015). Abnormal right atrial [18]F-FDG uptake was associated with PsAF (P = 0.010), whereas abnormal LA [18]F-FAPI uptake was associated with higher LAVI (P = 0.021) and lower low-density lipoprotein cholesterol (P = 0.006). [18]F-FDG and [18]F-FAPI PET demonstrated spatially divergent atrial uptake patterns in AF, suggesting cohort-level complementary information on metabolically active atrial remodeling and activated fibroblast-associated remodeling. This complementarity requires within-patient validation.

Bacterial biofilms enable microbial communities to withstand environmental stress and antibiotic challenge. Stenotrophomonas maltophilia is an opportunistic pathogen that frequently colonizes cystic fibrosis airways. Its chaperone-usher pathway (CUP) pilus, SMF-1, is essential for biofilm development, but its molecular architecture has remained unknown. Here, we present a 4.0 Å cryogenic electron microscopy (cryo-EM) structure demonstrating that the classic γ4 CUP pilus SMF-1 assembles into zigzag filaments that pair into antiparallel "pili couples" and higher order bundles. These bundles serve as intercellular tethers that drive rapid cell aggregation during biofilm initiation. Despite belonging to the classic CUP family, SMF-1 lacks the subunit interfaces required for canonical rod-like architectures, providing structural evidence of convergent evolution toward archaic-like biofilm bundling mechanisms. Furthermore, appendage-driven motility acts synergistically with SMF-1 pili to accelerate intercellular encounters and aggregate assembly. Together, these findings reveal a structural mechanism of pilus-mediated crosslinking promoting bacterial colonization.

Combined radiation-wound injury (CRWI) is difficult to heal because of persistent oxidative stress, inflammation, and impaired angiogenesis. Herein, a multifunctional pH and reactive oxygen species (ROS)-responsive hydrogel was prepared by dynamic crosslinking of Polygonati Rhizoma-derived polysaccharide fraction (PC) with phenylboronic acid-modified chitosan (CS-BA) through reversible boronate ester bonds. The obtained PC/CS-BA hydrogel was injectable and exhibited tissue adhesion, self-healing ability, and pH/ROS-responsive network disassembly. The optimized PC/CS-BA-1 hydrogel showed favorable mechanical stability and broad-spectrum antioxidant activity against O2•[-], ABTS•, PTIO•, and •OH radicals. In addition, the hydrogel displayed excellent in vitro hemocompatibility and cytocompatibility, effectively reduced irradiation-induced intracellular ROS accumulation, and inhibited cell apoptosis. In a mouse model combining a full-thickness dorsal wound with local irradiation, the hydrogel significantly accelerated wound closure, achieving 81.1% healing on day 7 and nearly complete closure on day 14. Histological analyses further confirmed improved epidermal regeneration, collagen remodeling, skin appendage formation, and angiogenesis. Overall, this PC/CS-BA hydrogel provides a responsive and bioactive wound dressing strategy for radiation-combined wound repair.