Beijing Institute of Radiation Medicine

Rapid and effective hemostasis is essential for the management of battlefield injuries and traumatic hemorrhages. Among various hemostatic agents, starch-based materials have attracted considerable attention due to their favorable biocompatibility, low immunogenicity, and cost-effectiveness. However, the potential of kudzu starch (KS) as a raw material for hemostatic applications remains underexplored. In this study, porous kudzu starch (PS) was crosslinked with sodium trimetaphosphate (STMP) to synthesize a novel hemostatic agent, STMP/PS (SPS), with enhanced functional performance. The structural and physicochemical properties of SPS were systematically characterized using Fourier-transform infrared (FT-IR) spectroscopy, Brunauer-Emmett-Teller (BET) surface area analysis, and other analytical techniques, confirming successful chemical modification and the formation of a highly porous architecture. SPS exhibited excellent water absorption and dye adsorption capacities. Hemostatic efficacy was evaluated through a series of in vitro and in vivo models, where SPS demonstrated significantly improved performance compared to a commercially available hemostatic product. Mechanistic investigations revealed that SPS facilitates red blood cell aggregation and platelet adhesion, thereby accelerating the coagulation cascade. In addition, biosafety assessments, including cytotoxicity, acute toxicity, and hemolysis assays, confirmed its excellent biocompatibility and low toxicity. These findings underscore the clinical potential of SPS as a rapid, effective, and safe starch-based hemostatic material.

With the widespread utilization of S band (2 GHz ∼ 4 GHz) microwave (MW) in communication, its potential health risks have drawn significant attention. The purpose of this study was to investigate the impacts of acute 2.856 GHz MW exposure on recognition memory, its corresponding functional brain network, and the relationships between them in rats.

Novel object recognition (NOR) tests were conducted to examine the influence of 50 mW/cm² acute 2.856 GHz MW on rat's recognition memory. Subsequently, resting state functional magnetic resonance imaging (rs-fMRI) was implemented to investigate the changes in the topological characteristics, long-range functional connectivity (FC), local FC assessed by regional homogeneity (ReHo), and fractional amplitude of low frequency fluctuation (fALFF) of rats' brain network related to recognition memory. Furthermore, the relationships between recognition memory and the potentially changed functional characteristics were investigated.

Our findings revealed that the acute MW exposure induced recognition memory decline in rats. Though no significant alterations were detected in topological properties, long-range FCs, and fALFF within the brain network related to recognition memory, the local FCs of bilateral perirhinal cortex and right hippocampus in rats exhibited marginally significant increases following the MW exposure. Moreover, in the Sham group, the local FC of the left perirhinal cortex demonstrated a significantly positive linear correlation with recognition memory ability (p = 0.0193, r = 0.7182). However, this linear relationship was disrupted after the MW exposure.

In conclusion, acute 2.856 GHz MW exposure can induce recognition memory impairments in rats. There is a positive linear relationship between recognition memory and the local FC of the left perirhinal cortex in normal rats. However, this relationship is disrupted after MW exposure, potentially due to maladaptive reorganization or failure of compensation within the brain region.