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Stroke is an acute cerebrovascular disease in which sudden interruption of blood supply to the brain or rupture of cerebral blood vessels cause damage to brain cells and consequently impair the patient's motor and cognitive abilities. A novel rehabilitation training model integrating brain-computer interface (BCI) and virtual reality (VR) not only promotes the functional activation of brain networks, but also provides immersive and interesting contextual feedback for patients. In this paper, we designed a hand rehabilitation training system integrating multi-sensory stimulation feedback, BCI and VR, which guides patients' motor imaginations through the tasks of the virtual scene, acquires patients' motor intentions, and then carries out human-computer interactions under the virtual scene. At the same time, haptic feedback is incorporated to further increase the patients' proprioceptive sensations, so as to realize the hand function rehabilitation training based on the multi-sensory stimulation feedback of vision, hearing, and haptic senses. In this study, we compared and analyzed the differences in power spectral density of different frequency bands within the EEG signal data before and after the incorporation of haptic feedback, and found that the motor brain area was significantly activated after the incorporation of haptic feedback, and the power spectral density of the motor brain area was significantly increased in the high gamma frequency band. The results of this study indicate that the rehabilitation training of patients with the VR-BCI hand function enhancement rehabilitation system incorporating multi-sensory stimulation can accelerate the two-way facilitation of sensory and motor conduction pathways, thus accelerating the rehabilitation process.

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Brain-computer interface (BCI) based on steady-state visual evoked potential (SSVEP) have attracted much attention in the field of intelligent robotics. Traditional SSVEP-based BCI systems mostly use synchronized triggers without identifying whether the user is in the control or non-control state, resulting in a system that lacks autonomous control capability. Therefore, this paper proposed a SSVEP asynchronous state recognition method, which constructs an asynchronous state recognition model by fusing multiple time-frequency domain features of electroencephalographic (EEG) signals and combining with a linear discriminant analysis (LDA) to improve the accuracy of SSVEP asynchronous state recognition. Furthermore, addressing the control needs of disabled individuals in multitasking scenarios, a brain-machine fusion system based on SSVEP-BCI asynchronous cooperative control was developed. This system enabled the collaborative control of wearable manipulator and robotic arm, where the robotic arm acts as a "third hand", offering significant advantages in complex environments. The experimental results showed that using the SSVEP asynchronous control algorithm and brain-computer fusion system proposed in this paper could assist users to complete multitasking cooperative operations. The average accuracy of user intent recognition in online control experiments was 93.0%, which provides a theoretical and practical basis for the practical application of the asynchronous SSVEP-BCI system.

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Precise monitoring of biomolecular radiation damage is crucial for understanding X-ray-induced cell injury and improving the accuracy of clinical radiotherapy. We present the design and performance of lanthanide-DNA-origami nanodosimeters for directly visualizing radiation damage at the single-particle level. Lanthanide ions (Tb3+ or Eu3+) coordinated with DNA origami nanosensors enhance the sensitivity of X-ray irradiation. Atomic force microscopy (AFM) revealed morphological changes in Eu3+-sensitized DNA origami upon X-ray irradiation, indicating damage caused by ionization-generated electrons and free radicals. We further demonstrated the practical applicability of Eu3+-DNA-origami integrated chips in precisely monitoring radiation-mediated cancer radiotherapy. Quantitative results showed consistent trends with flow cytometry and histological examination under comparable X-ray irradiation doses, providing an affordable and user-friendly visualization tool for preclinical applications. These findings provide new insights into the impact of heavy metals on radiation-induced biomolecular damage and pave the way for future research in developing nanoscale radiation sensors for precise clinical radiography.

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Diarrheas are common risks faced by piglets during the weaning period. This study investigated the alleviating effects of artificial parasin I protein (API) on growth performance and intestinal health of weaned pigs upon enterotoxigenic Escherichia coli (ETEC) challenge. Sixty piglets were randomly divided into five groups and fed a basal diet (CON) or basal diet supplemented with API at 0, 750, and 1500 mg/kg or antibiotics for 5 weeks. On d 15 and 25, piglets were challenged with ETEC K88 except for the CON group. Before the ETEC challenge (d 1-14), dietary API supplementation improved growth performance, and 750 mg API increased (P < 0.05) the average daily gain (ADG), decreased (P < 0.05) feed to gain ratio (F/G) and diarrhea index of weaned piglets. ETEC challenge (during d 15-35) reduced growth performance and increased (P < 0.01) the F/G, diarrhea rate, and diarrhea index. This event was accompanied by the numerically increased malondialdehyde (MDA) levels in serum and ileum, the decreased (P < 0.05) zonula-occludens-1 (ZO-1) and interleukin-6 (IL-6) in the ileum, and the increased (P = 0.04) secretory immunoglobulin A (sIgA) protein in the ileum. Artificial parasin I protein supplementation alleviated the negative impact of ETEC. The 750 mg/kg API inclusion elevated (P < 0.05) ADG and decreased (P < 0.05) F/G. Two levels of API decreased (P < 0.01) the diarrhea rate and diarrhea index. Meanwhile, API inclusion decreased (P < 0.01) the crypt depth in the jejunum, elevated (P < 0.05) villus height in the duodenum and villus height to crypt depth ratio in the duodenum and ileum, up-regulated (P < 0.05) ZO-1 gene, and down-regulated (P < 0.05) mucin-2 gene in the jejunum, and 1500 mg/kg API decreased (P < 0.01) sIgA level and down-regulated (P < 0.05) IL-1ß gene in the ileum. Furthermore, 750 mg/kg API elevated (P < 0.01) Bifidobacteria population and acetic acid concentrations in the cecal chyme. In conclusion, API supplementation alleviates the negative impact of ETEC on growth performance and intestinal health, thus can be applied as an antibiotic alternative in weaned piglets.

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BACKGROUND: History-taking is an essential clinical competency for qualified doctors. The limitations of the standardized patient (SP) in taking history can be addressed by the virtual standardized patient (VSP). This paper investigates the accuracy of virtual standardized patient simulators and evaluates the applicability of the improved system's accuracy for diagnostic teaching support and performance assessment. METHODS: Data from the application of VSP to medical residents and students were gathered for this prospective study. In a human-machine collaboration mode, students completed exams involving taking SP histories while VSP provided real-time scoring. Every participant had VSP and SP scores. Lastly, using the voice and text records as a guide, the technicians will adjust the system's intention recognition accuracy and speech recognition accuracy. RESULTS: The research revealed significant differences in scoring across several iterations of VSP and SP (p < 0.001). Across various clinical cases, there were differences in application accuracy for different versions of VSP (p < 0.001). Among training groups, the diarrhea case showed significant differences in speech recognition accuracy (Z = -2.719, p = 0.007) and intent recognition accuracy (Z = -2.406, p = 0.016). Scoring and intent recognition accuracy improved significantly after system upgrades. CONCLUSION: VSP has a comprehensive and detailed scoring system and demonstrates good scoring accuracy, which can be a valuable tool for history-taking training.

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Treating kidney diseases from the perspective of spleen is an important clinical method in traditional Chinese medicine (TCM) for anti-renal fibrosis (RF). Si-jun-zi decoction (SJZD), a classic formula for qi-invigorating and spleen-invigorating, has been reported to alleviate RF. This study aims to investigate the potential mechanism by which SJZD attenuates RF. The results demonstrated notable improvements in renal function levels, inflammation and fibrosis indices in UUO-mice following SJZD intervention. The main active ingredients identified were Quercetin, Kaempferol, Naringenin and 7-Methoxy-2-methyl isoflavone. Furthermore, STAT3, MAPK3, MYC were confirmed as key targets. Additionally, GO enrichment analysis demonstrated that SJZD delayed RF primarily by regulating oxidative stress and other biological mechanisms. KEGG enrichment analysis revealed the involvement of pathways such as Lipid and atherosclerosis signaling pathway, MAPK signaling pathway and other pathways in the reno-protective effects of SJZD. The molecular docking results revealed that the active ingredients of SJZD were well-bound and stable to the core targets. The experiments results revealed that Quercetin, Kaempferol, and Naringenin not only improved the morphology of TGF-ß-induced HK-2 cells but also reversed the expression of α-SMA, COL1A1 and MAPK, thereby delaying the progression of RF. The anti-RF effects of SJZD were exerted through multi-components, multi-targets and multi-pathways.

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The gut microbiome-metabolites-kidney axis is a potential target for treating diabetic kidney disease (DKD). Our previous study found that Liraglutide attenuated DKD in rats by decreasing renal tubular ectopic lipid deposition (ELD) and serum metabolites levels, including L-5-Oxoproline (5-OP). However, the response of gut microbiome-metabolites-kidney axis to Liraglutide in DKD rats and the effect of 5-OP on ELD remain unknown. In this study, Sprague-Dawley rats were used as an animal model of DKD. They were subjected to a high fat diet, streptozotocin and uninephrectomy, followed by Liraglutide treatment (0.4 mg/kg d). Additionally, HK-2 cells were incubated with 30 mM glucose and 200 µM palmitate for 24h, and exposed to different concentrations of 5-OP. In DKD rats, Liraglutide dramatically improved the renal tubule structure. It increased the Simpson index (F = 4.487, p = 0.035) and reduced the Actinobacteria-to-Bacteroidetes ratio (F = 6.189, p = 0.014). At the genus level, Liraglutide increased the relative abundance of Clostridium, Oscillospira, Sarcina, SMB53, and 02d06 while decreasing that of Allobaculum. Meanwhile, 13 metabolites were significantly altered after Liraglutide treatment. Multi-omics analysis found that 5-OP levels were positively correlated with Clostridium abundance but negatively correlated with renal injury related indicators. In HK-2 cells, 5-OP significantly reduced the ELD in a dose-dependent manner through inhibiting the expression of SREBP1 and FAS. Overall, the renoprotective effect of Liraglutide in DKD rats is linked to the improvement of the gut microbiota composition and increased serum 5-OP levels, which may reduce ELD in renal tubular cells by lowering lipid synthesis.

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Antibiotic resistance poses a serious threat to public health globally, reducing the effectiveness of conventional antibiotics in treating bacterial infections. ESKAPE pathogens are a group of highly transmissible bacteria that mainly contribute to the spread of antibiotic resistance and cause significant morbidity and mortality in humans. Phylloseptins, a class of antimicrobial peptides (AMPs) derived from Phyllomedusidae frogs, have been proven to have antimicrobial activity via membrane interaction. However, their relatively high cytotoxicity and low stability limit the clinical development of these AMPs. This project aims to study the antimicrobial activity and mechanisms of a phylloseptin-like peptide, phylloseptin-TO2 (PSTO2), following rational amino acid modification. Here, PSTO2 (FLSLIPHAISAVSALAKHL-NH2), identified from the skin secretion of Phyllomedusa tomopterna, was used as the template for modification to enhance antimicrobial activity. Adding positive charges to PSTO2 through substitution with L-lysines enhanced the interaction of the peptides with cell membranes and improved their antimicrobial efficacy. The analogues SRD7 and SR2D10, which incorporated D-lysines, demonstrated significant antimicrobial effects against Staphylococcus aureus and methicillin-resistant Staphylococcus aureus (MRSA) while also showing reduced haemolytic activity and cytotoxicity, resulting in a higher therapeutic index. Additionally, SRD7, modified with D-lysines, exhibited notable anti-proliferative properties against human lung cancer cell lines, including H838 and H460. This study thus provides a potential development model for new antibacterial and anti-cancer drugs combating antibiotic resistance.

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In recent decades, antimicrobial peptides (AMPs) have emerged as highly promising candidates for the next generation of antibiotic agents, garnering significant attention. Although their potent antimicrobial activities and ability to combat drug resistance make them stand out among alternative agents, their poor stability has presented a great challenge for further development. In this work, we report a novel Kunitzin AMP, Kunitzin-OL, from the frog Odorrana lividia, exhibiting dual antimicrobial and anti-trypsin activities. Through functional screening and comparison with previously reported Kunitzin peptides, we serendipitously discovered a unique motif (-KVKF-) and unveiled its crucial role in the antibacterial functions of Kunitzin-OL by modifying it through motif removal and duplication. Among the designed derivatives, peptides 4 and 8 demonstrated remarkable antimicrobial activities and low cytotoxicity, with high therapeutic index (TI) values (TI4 = 20.8, TI8 = 20.8). Furthermore, they showed potent antibacterial efficacy against drug-resistant Escherichia coli strains and exhibited lipopolysaccharide (LPS)-neutralising activity, effectively alleviating LPS-induced inflammatory responses. Overall, our findings provide a new short motif for designing effective AMP drugs and highlight the potential of the Kunitztin trypsin inhibitory loop as a valuable motif for the design of AMPs with enhancing proteolytic stability.

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Mental fatigue during long-term motor imagery (MI) may affect intention recognition in MI applications. However, the current research lacks the monitoring of mental fatigue during MI and the definition of robust biomarkers. The present study aims to reveal the effects of mental fatigue on motor imagery recognition at the brain region level and explore biomarkers of mental fatigue. To achieve this, we recruited 10 healthy participants and asked them to complete a long-term motor imagery task involving both right- and left-handed movements. During the experiment, we recorded 32-channel EEG data and carried out a fatigue questionnaire for each participant. As a result, we found that mental fatigue significantly decreased the subjects' motor imagery recognition rate during MI. Additionally the theta power of frontal, central, parietal, and occipital clusters significantly increased after the presence of mental fatigue. Furthermore, the phase synchronization between the central cluster and the frontal and occipital lobes was significantly weakened. To summarize, the theta bands of frontal, central, and parieto-occipital clusters may serve as powerful biomarkers for monitoring mental fatigue during motor imagery. Additionally, changes in functional connectivity between the central cluster and the prefrontal and occipital lobes during motor imagery could be investigated as potential biomarkers.

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BACKGROUND: The study aimed to investigate the difference in clinical efficacy between apheresis platelets and buffy coat-derived platelet concentrates infusion in patients with hematological diseases. METHODS: A total of 218 patients with hematological diseases were enrolled in Xi'an Central Hospital, from January 2023 to October 2023, and randomly divided into two groups: 109 patients were treated with apheresis platelet transfusion (AP group) and 109 patients with buffy coat derived platelet concentrates (BC-PC group). Platelet counts were measured before and 24 hours after transfusion, and the corrected platelet ascending number (CCI) and platelet recovery rate (PPR) were calculated. The clinical efficacy and blood transfusion reaction were observed. RESULTS: After 24 hours of platelet transfusion, there was no significant difference in the platelet count between the AP and BC-PC groups (p > 0.05). However, CCI and PPR significantly differed between the two groups (p < 0.05). Moreover, the incidence of transfusion reaction in the AP group was significantly lower than in the BC-PC group. CONCLUSIONS: The clinical efficacy of buffy coat-derived platelet concentrates is lower than that of apheresis platelets, but it can also improve the patient's condition and quality of life. Therefore, clinicians could rationally use BC-PC, according to the actual situation of the patients.

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The objectives of this study were to investigate the effects of extrusion on the chemical compositions, surface structure, and molecular structure of brewer's spent grain (BSG), as well as to determine the digestible energy (DE), metabolizable energy (ME), apparent total tract digestibility (ATTD) of nutrients and energy, and amino acid (AA) digestibility of extruded BSG when fed to growing pigs. Firstly, we determined the changes in chemical compositions and molecular structure of both non-extruded and extruded BSG. In Exp. 1, eighteen growing pigs were fed three different diets including one corn-soybean meal basal diet and two experimental diets containing 20% BSG with or without extrusion. Feces and urine were collected to determine the ATTD of nutrients and energy, DE, and ME of extruded or non-extruded BSG. In Exp. 2, eighteen growing pigs were fed three different diets including 30% BSG with or without extrusion, and an N-free diet. Ileal digesta was collected through the slaughter method to determine the apparent ileal digestibility (AID) and standardized ileal digestibility (SID) of AA of extruded or non-extruded BSG. The results showed that extrusion reduced the neutral detergent fiber, hemicellulose and cellulose contents in BSG, and increased the Arg, Asp, Glu, Ser, Tyr, total indispensable AA and total AA contents of BSG, altered the surface structure of BSG, increased the peak absorbance in amide I and amide II height, amide II and amide (I+II) area, α-helix height, decreased ß-sheet height, and weakened band intensities in cellulosic compounds (CELC) area, structural carbohydrates (SCHO) area, carbohydrates area (CHO) peak 2 and 3 height, the area ratio of CELC: CHO and CELC: SCHO. Moreover, DE and ME values and ATTD of energy, dry matter, crude protein, acid detergent fiber, neutral detergent fiber, cellulose and hemicellulose increased (P < 0.05) when pigs were fed extruded BSG diets. The AID and SID of Arg, His, Lys, Val and Gly increased, whereas the AID and SID of Ile and Leu decreased when pigs were fed extrusion diets (P < 0.05). Our study found that the ATTD of nutrients and AA digestibility in pigs were positively correlated with the molecular structure of proteins, and negatively correlated with the molecular structure of carbohydrates (P < 0.05). These findings suggested that extrusion had the potential to improve the nutrient digestibility of BSG by altering its chemical compositions, surface structure, and molecular structure.

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The beneficial effects of xylo-oligosaccharides (XOS) on the intestine have been widely reported, including anti-inflammation, antioxidant, maintenance of intestinal epithelial barrier, and treatment of intestinal injury. However, the specific mechanism of XOS in mitigating intestinal injury in weaned piglets remains unclear. Therefore, this study aimed to explore the specific mechanism of XOS in mitigating intestinal injury. The study is a complete randomized design with 24 weaned piglets in a 2 × 2 factorial arrangement that includes diet treatments (basal diet vs 0.02% XOS) and immunological challenge [saline vs lipopolysaccharide (LPS)]. All piglets were fed a basal diet or a XOS diet for 21 days. On day 22, all piglets received an injection of LPS or saline. In this study, dietary XOS increased jejunal villus height, reduced crypt depth and oxidative stress, and enhanced the gene and protein expression of Claudin-1, Occludin, and zonula occludens 1 (P < 0.05). The piglets fed the XOS diet had lower serum Diamine oxidase activity and D-lactic acid content (P < 0.05). In addition, dietary XOS regulates endoplasmic reticulum (ER)-mitochondria system function and the expression of key molecules, including mitochondrial dynamics dysfunction [mitofusin (Mfn)-1, optic atrophy 1, fission 1, and dynamin-related protein 1], ER stress [activating transcription factor 4 (ATF4), ATF6, C/EBP homologous protein, eukaryotic initiation factor 2α, glucose-regulated protein (GRP) 78, GRP94 and protein kinase R-like ER kinase] and the mitochondria-associated ER membranes (MAM) disorders (Mfn2, GRP75 and voltage-dlependent anion channel 1) (P < 0.05). Therefore, the findings to indicate that dietary XOS is effective against LPS-induced jejunal injury may be attributed to its ability to alleviate mitochondrial dynamics dysfunction, ER stress, and MAM disorders.

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Infections by drug-resistant microorganisms are a threat to global health and antimicrobial peptides are considered to be a new hope for their treatment. Temporin-WY2 was identified from the cutaneous secretion of the Ranidae frog, Amolops wuyiensis. It presented with a potent anti-Gram-positive bacterial efficacy, but its activity against Gram-negative bacteria and cancer cell lines was unremarkable. Also, it produced a relatively high lytic effect on horse erythrocytes. For further improvement of its functions, a perfect amphipathic analogue, QUB-1426, and two lysine-clustered analogues, 6K-WY2 and 6K-1426, were synthesised and investigated. The modified peptides were found to be between 8- and 64-fold more potent against Gram-negative bacteria than the original peptide. Additionally, the 6K analogues showed a rapid killing rate. Also, their antiproliferation activities were more than 100-fold more potent than the parent peptide. All of the peptides that were examined demonstrated considerable biofilm inhibition activity. Moreover, QUB-1426, 6K-WY2 and 6K-1426, demonstrated in vivo antimicrobial activity against MRSA and E. coli in an insect larvae model. Despite observing a slight increase in the hemolytic activity and cytotoxicity of the modified peptides, they still demonstrated a improved therapeutic index. Overall, QUB-1426, 6K-WY2 and 6K-1426, with dual antimicrobial and anticancer functions, are proposed as putative drug candidates for the future.

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Phosphorus (P) is a vital nutrient for the growth of marine organisms. Tidal cycle had major influence on various biogeochemical parameters of the bay and changed nutrients input with the ebb and flow of the tide. Seawater was collected by synchronous continuous observation during summer in 2021, to investigate tide drives total phosphorus (TP) variation on the concentration, speciation and exchange flux between Shuidong Bay (SDB) and South China Sea (SCS). Results indicated that there was significant tidal variation in exchange flux of TP between SDB and SCS. DIP and DOP were the main speciation of TDP in different tidal periods, accounting for 53.9 % and 46.1 %TP flowed from SCS to SDB, and monthly exchange flux was about 21.26 t. This study provides new insights in P tidal cycling across the semi-enclosed bay-coastal water continuum, which was implications for understanding P biogeochemical process and primary production dynamics in coastal water.

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Particles in space cause irradiation damage to the solar cells (SCs), resulting in the degradation of their performance. Quantum dot solar cells (QDSCs) have higher theoretical efficiency and better irradiation resistance than the conventional GaAs SCs, which makes them highly promising for application in space. In this paper, we study the proton irradiation effect on InAs/GaAs0.8Sb0.2 QDSCs by SRIM program. The simulation result shows that the InAs/GaAs0.8Sb0.2 QDSCs have fewer vacancies than GaAs SCs when irradiated with low-energy proton, which indicates that the InAs/GaAs0.8Sb0.2 QDSCs have better anti-irradiation characteristics. The study about displacements per atom and proton concentration in two SCs shows that protons with low energy and high irradiation fluences will cause more serious damage in InAs/GaAs0.8Sb0.2 QDSCs. In addition, the proton incident angle affects the vacancy distribution, while the number of QD layers has little effect on it.

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Filamentous fungi are prolific producers of bioactive natural products and play a vital role in drug discovery. Yet, their potential cannot be fully exploited since many biosynthetic genes are silent or cryptic under laboratory culture conditions. Several strategies have been applied to activate these genes, with heterologous expression as one of the most promising approaches. However, successful expression and identification of new products are often hindered by host-dependent factors, such as low gene targeting efficiencies, a high metabolite background, or a lack of selection markers. To overcome these challenges, we have constructed a Penicillium crustosum expression host in a pyrG deficient strain by combining the split-marker strategy and CRISPR-Cas9 technology. Deletion of ligD and pcribo improved gene targeting efficiencies and enabled the use of an additional selection marker in P. crustosum. Furthermore, we reduced the secondary metabolite background by inactivation of two highly expressed gene clusters and abolished the formation of the reactive ortho-quinone methide. Finally, we replaced the P. crustosum pigment gene pcr4401 with the commonly used Aspergillus nidulans wA expression site for convenient use of constructs originally designed for A. nidulans in our P. crustosum host strain. As proof of concept, we successfully expressed a single polyketide synthase gene and an entire gene cluster at the P. crustosum wA locus. Resulting transformants were easily detected by their albino phenotype. With this study, we provide a highly efficient platform for heterologous expression of fungal genes. KEY POINTS: Construction of a highly efficient Penicillium crustosum heterologous expression host Reduction of secondary metabolite background by genetic dereplication strategy Integration of wA site to provide an alternative host besides Aspergillus nidulans.

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The advantage of low-temperature forming through direct ink writing (DIW) 3D printing is becoming a strategy for the construction of innovative drug delivery systems (DDSs). Optimization of the complex formulation, including factors such as the printing ink, presence of solvents, and potential low mechanical strength, are challenges during process development. This study presents an application of DIW to fabricate water-soluble, high-dose, and sustained-release DDSs. Utilizing poorly compressible metformin hydrochloride as a model drug, a core-shell delivery system was developed, featuring a core composed of 96 % drug powder and 4 % binder, with a shell structure serving as a drug-release barrier. This design aligns with the sustained-release profile of traditional processes, achieving a 25.8 % reduction in volume and enhanced mechanical strength. The strategy facilitates sustained release of high-dose water-soluble formulations for over 12 h, potentially improving patient compliance by reducing formulation size. Process optimization and multi-batch flexibility were also explored in this study. Our findings provide a valuable reference for the development of innovative DDSs and 3D-printed drugs.

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Selenium (Se)-rich Cyclocarya paliurus is popular for its bioactive components, and exogenous Se fortification is the most effective means of enrichment. However, the effects of exogenous Se fortification on the nutritional quality of C. paliurus are not well known. To investigate the nutrient contents and antioxidant properties of C. paliurus following Se treatment, we used a foliar spray to apply Se in two forms-chemical nano-Se (Che-SeNPs) and sodium selenite (Na2SeO3). Sampling began 10 days after spraying and was conducted every 5 days until day 30. The Se, secondary metabolite, malondialdehyde contents, antioxidant enzyme activity, Se speciation, and Se-metabolism-related gene expression patterns were analyzed in the collected samples. Exogenous Se enhancement effectively increased the Se content of leaves, reaching a maximum on days 10 and 15 of sampling, while the contents of flavonoids, triterpenes, and polyphenols increased significantly during the same period. In addition, the application of Se significantly enhanced total antioxidant activity, especially the activity of the antioxidant enzyme peroxidase. Furthermore, a positive correlation between the alleviation of lipid peroxidation and Se content was observed, while methylselenocysteine formation was an effective means of alleviating Se stress. Finally, Na2SeO3 exhibited better absorption and conversion efficiency than Che-SeNPs in C. paliurus.

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The overuse of traditional antibiotics has resulted in bacterial resistance and seriously compromised the therapeutic efficacy of traditional antibiotics, making the exploration of new antimicrobials particularly important. Several studies have shown that bioactive peptides have become an important source of new antimicrobial drugs due to their broad-spectrum antibacterial action and lack of susceptibility to resistance. In this study, a novel bioactive peptide Nigrosin-6VL was characterised from the skin secretion of the golden cross band frog, Odorrana andersonii, by using the 'shotgun' cloning strategy. Modifications on the Rana Box of Nigrosin-6VL revealed its critical role in antimicrobial functions. The peptide analogue, 2170-2R, designed to preserve the Rana Box structure while enhancing cationicity, exhibited improved therapeutic efficacy, particularly against Gram-negative bacteria, with a therapeutic value of 45.27. Synergistic studies demonstrated that 2170-2R inherits the synergistic antimicrobial activities of the parent peptides and effectively enhances the antimicrobial capacity of cefepime and gentamicin against both planktonic cells and biofilms. Specifically, 2170-2R can synergise effectively with cefepime and gentamicin against different strains of P. aeruginosa biofilms. Consequently, 2170-2R holds promise as a potent antimicrobial agent developed to combat infections induced by Pseudomonas aeruginosa.