Staphylococcus aureus is a Gram-positive bacterium with strong pathogenicity. With the widespread use of antibiotics， its multi-drug resistance has gradually increased. Among them， methicillin-resistant S. aureus （MRSA） is one of the main pathogens of hospital and community infections. Antimicrobial peptides are short-chain peptides with good antibacterial effects and low drug resistance， which have been widely studied in recent years. This study summarizes the mechanism of action of antimicrobial peptides and related study on antimicrobial peptides against MRSA from different sources. It is found that the mechanisms of action of antimicrobial peptides include targeting bacterial cell membranes， bacterial cells， and bacterial cell walls， etc. Besides isolating antimicrobial peptides with anti-MRSA activity from animals， plants， and microorganisms， antimicrobial peptides can also be obtained through synthetic methods. Among them， GHa-derived peptides from animal sources， Ib-AMP4 from plant sources， Ph-SA from microbial sources， the synthetic peptide LLKLLLKLL-NH2， and so on， due to their effective antibacterial activity， rapid bactericidal speed， and low toxicity， are promising candidates for anti-MRSA drugs.

BACKGROUND:In recent years,deep learning technologies have been increasingly applied in the field of oral medicine,enhancing the efficiency and accuracy of oral imaging analysis and promoting the rapid development of intelligent oral medicine. OBJECTIVE:To elaborate the current research status,advantages,and limitations of deep learning based on oral imaging in the diagnosis and treatment decision-making of oral diseases,as well as future prospects,exploring new directions for the transformation of oral medicine under the backdrop of deep learning technology. METHODS:PubMed was searched for literature related to deep learning in oral medical imaging published from January 2017 to January 2024 with the search terms"deep learning,artificial intelligence,stomatology,oral medical imaging."According to the inclusion criteria,80 papers were finally included for review. RESULTS AND CONCLUSION:(1)Classic deep learning models include artificial neural networks,convolutional neural networks,recurrent neural networks,and generative adversarial networks.Scholars have used these models in competitive or cooperative forms to achieve more efficient interpretation of oral medical images.(2)In the field of oral medicine,the diagnosis of diseases and the formulation of treatment plans largely depend on the interpretation of medical imaging data.Deep learning technology,with its strong image processing capabilities,aids in the diagnosis of diseases such as dental caries,periapical periodontitis,vertical root fractures,periodontal disease,and jaw cysts,as well as preoperative assessments for procedures such as third molar extraction and cervical lymph node dissection,helping clinicians improve the accuracy and efficiency of decision-making.(3)Although deep learning is promising as an important auxiliary tool for the diagnosis and treatment of oral diseases,it still has certain limitations in model technology,safety ethics,and legal regulation.Future research should focus on demonstrating the scalability,robustness,and clinical practicality of deep learning,and finding the best way to integrate automated deep learning decision support systems into routine clinical workflows.

BACKGROUND:Traditional methods of urinary tract reconstruction are limited by donor scarcity,high complication rates,and suboptimal functional recovery.Tissue engineering strategies offer new directions in this field.Since the urinary tract is mainly composed of muscle tissue,the key is to find suitable seed cells and efficiently induce them to differentiate into smooth muscle cells.Comparative studies on the efficacy of different smooth muscle cell induction regimens are still lacking. OBJECTIVE:To isolate,culture,and identify human urine-derived stem cells,and to compare the effects of two different induction protocols. METHODS:Human urine-derived stem cells were isolated from urine samples of 11 healthy adult volunteers by multiple centrifugations.Surface markers were identified by flow cytometry.The multi-directional differentiation potential of human urine-derived stem cells was verified through osteogenic and adipogenic differentiation.Differentiation was induced by transforming growth factor-β1 or transforming growth factor-β1 combined with platelet derived growth factor for 14 days.Immunofluorescence staining and western blot assay were employed to compare the expression differences of smooth muscle-specific proteins(α-SMA and SM22). RESULTS AND CONCLUSION:(1)Urine-derived stem cells were successfully isolated from the eight urine samples of healthy people.These cells exhibit a"rice grain"-like morphology and possess a robust proliferative capacity.(2)Urine-derived stem cells exhibited high expression of mesenchymal stem cell surface markers(CD73,CD90,and CD44)and extremely low expression of hematopoietic stem cell surface markers(CD34 and CD45).These cells did not express CD19,CD105,and HLA-DR.(3)After osteogenic and adipogenic differentiation,the formation of calcium nodules and lipid droplets was observed,with positive staining results from Alizarin Red S and Oil Red O staining.(4)After 14 days of smooth muscle induction culture,immunofluorescence staining revealed that the smooth muscle differentiation rate of urine-derived stem cells treated with a combination of transforming growth factor-β1 and platelet derived growth factor was significantly higher compared to those treated with transforming growth factor-β1 alone(P<0.005).(5)After 14 days of smooth muscle induction culture,western blot assay further demonstrated that the expression levels of α-SMA and SM22 in the transforming growth factor-β1/platelet derived growth factor group were significantly elevated compared to those in the transforming growth factor-β1 only group(P<0.005).These findings confirm that urine-derived stem cells can be non-invasively isolated using multiple rounds of centrifugation.Compared with transforming growth factor-β1 alone,the combination of transforming growth factor-β1 and platelet derived growth factor can improve the efficiency of inducing urine-derived stem cells to differentiate into smooth muscle cells.

Peptide-based radiopharmaceuticals targeting integrin α5β1 show promise for precise tumor diagnosis and treatment. However, current peptide-based radioligands that target α5β1 demonstrate inadequate in vivo performance owing to limited tumor retention. The use of PEGylation to enhance the tumor retention of radiopharmaceuticals by prolonging blood circulation time poses a risk of increased blood toxicity. Therefore, a PEGylation strategy that boosts tumor retention while minimizing blood circulation time is urgently needed. Here, we developed a PEGylation-enabled peptide multidisplay platform (PEGibody) for PR_b, an α5β1 targeting peptide. PEGibody generation involved PEGylation and self-assembly. [⁶⁴Cu]QM-2303 PEGibodies displayed spherical nanoparticles ranging from 100 to 200 nm in diameter. Compared with non-PEGylated radioligands, [⁶⁴Cu]QM-2303 demonstrated enhanced tumor retention time due to increased binding affinity and stability. Importantly, the biodistribution analysis confirmed rapid clearance of [⁶⁴Cu]QM-2303 from the bloodstream. Administration of a single dose of [¹⁷⁷Lu]QM-2303 led to robust antitumor efficacy. Furthermore, [⁶⁴Cu]/[¹⁷⁷Lu]QM-2303 exhibited low hematological and organ toxicity in both healthy and tumor-bearing mice. Therefore, this study presents a PEGibody-based radiotheranostic approach that enhances tumor retention time and provides long-lasting antitumor effects without prolonging blood circulation lifetime. The PEGibody-based radiopharmaceutical [⁶⁴Cu]/[¹⁷⁷Lu]QM-2303 shows great potential for positron emission tomography imaging-guided targeted radionuclide therapy for α5β1-overexpressing tumors.

The activation proteins released by fibroblasts in the tumor microenvironment regulate tumor growth, migration, and treatment response, thereby influencing tumor progression and therapeutic outcomes. Owing to the proliferation and metastasis of tumors, fibroblast activation protein (FAP) is typically highly expressed in the tumor stroma, whereas it is nearly absent in adult normal tissues and benign lesions, making it an attractive target for precision medicine. Radiolabeled agents targeting FAP have the potential for targeted cancer diagnosis and therapy. This comprehensive review aims to describe the evolution of FAPI-based radiopharmaceuticals and their structural optimization. Within its scope, this review summarizes the advances in the use of radiolabeled small molecule inhibitors for tumor imaging and therapy as well as the modification strategies for FAPIs, combined with insights from structure-activity relationships and clinical studies, providing a valuable perspective for radiopharmaceutical clinical development and application.

Ferroptosis of chondrocytes is a significant contributor to osteoarthritis (OA), for which there is still a lack of safe and effective therapeutic drugs targeting ferroptosis. Here, we screen for anti-ferroptotic drugs in Food and Drug Administration (FDA)-approved drug library via a high-throughput manner in chondrocytes. We identified a group of FDA-approved anti-ferroptotic drugs, among which vitamin K showed the most powerful protective effect. Further study demonstrated that vitamin K effectively inhibited ferroptosis and alleviated the extracellular matrix (ECM) degradation in chondrocytes. Intra-articular injection of vitamin K inhibited ferroptosis and alleviated OA phenotype in destabilization of the medial meniscus (DMM) mouse model. Mechanistically, transcriptome sequencing and knockdown experiments revealed that the anti-ferroptotic effects of vitamin K depended on growth arrest-specific 6 (Gas6). Furthermore, exogenous expression of Gas6 was found to inhibit ferroptosis through the AXL receptor tyrosine kinase (AXL)/phosphatidylinositol 3-kinase (PI3K)/AKT serine/threonine kinase (AKT) axis. Together, we demonstrate that vitamin K inhibits ferroptosis and alleviates OA progression via enhancing Gas6 expression and its downstream pathway of AXL/PI3K/AKT axis, indicating vitamin K as well as Gas6 to serve as a potential therapeutic target for OA and other ferroptosis-related diseases.

Liraglutide (Lira), a glucagon-like peptide-1 (GLP-1) receptor agonist approved for diabetes and obesity, has shown significant potential in treating metabolic dysfunction-associated steatotic liver disease (MASLD). However, its systematic molecular regulation and mechanisms remain underexplored. In this study, a mouse model of MASLD was developed using a high-fat diet (HFD), followed by Lira administration. Proteomics and glycoproteomics were analyzed using label-free liquid chromatography-tandem mass spectrometry (LC-MS/MS), while potential molecular target analysis was conducted via quantitative real-time polymerase chain reaction (qPCR) and Western blotting. Our results revealed that Lira treatment significantly reduced liver weight and serum markers, including alanine aminotransferase (ALT) and others, with glycosylation changes playing a more significant role than overall protein expression. The glycoproteome identified 255 independent glycosylation sites, emphasizing the impact of Lira on amino acid, carbohydrate metabolism, and ferroptosis. Simultaneously, proteomic analysis highlighted its effects on lipid metabolism and fibrosis pathways. 21 signature molecules, including 7 proteins and 14 N-glycosylation sites (N-glycosites), were identified as potential targets. A Lira hydrogel formulation (Lira@fibrin (Fib) Gel) was developed to extend drug dosing intervals, offering enhanced therapeutic efficacy in managing chronic metabolic diseases. Our study demonstrated the importance of glycosylation regulation in the therapeutic effects of Lira on MASLD, identifying potential molecular targets and advancing its clinical application for MASLD treatment.

Objective　To explore the effect of Mp1p on host macrophages through transcriptomics combined with metabolomics. Methods Firstly, a THP-1 macrophage strain (THP-1-Mp1p+) stably expressing Mp1p was constructed using lentivirus. Secondly, using high-throughput RNA sequencing (RNA Seq) technology, the expression level of intracellular mRNA was detected in transcriptomics analysis to determine differentially expressed genes; In metabolomics analysis, metabolite identification was performed through database comparison, and pathway analysis was performed on differential metabolites to reveal potential mechanisms of action. Finally, the results of metabolomics and transcriptomics were combined for analysis, and differential metabolites and genes were analyzed to further elucidate the mechanism of action of Mp1p on macrophages. Results Transcriptome analysis showed that, compared with the negative control group, the THP-1-Mp1p+ group had a total of 1 180 differentially expressed genes (DEGs), with 345 upregulated genes and 835 downregulated genes. GO enrichment analysis of DEGs showed that there were 135 differentially expressed genes, including 105 in biological processes (BP), 28 in cellular components (CC), and 2 in molecular functions (MF). The KEGG analysis results showed that the effect of Mp1p on THP-1 macrophages was highly correlated with the TNF pathway. The metabolomic analysis found that both the blank control group and the THP-1-Mp1p+ macrophage group achieved good separation between QC samples in both positive and negative ion modes. The threshold for significant differential metabolites was set at: VIP≥1 and T-test P<0.05, resulting in the identification of 488 differential metabolites, with 230 in the positive ion mode and 258 in the negative ion mode. Pathway enrichment analysis of the identified metabolites pointed to significant enrichment in metabolic pathways. The combined analysis confirmed that the tumor necrosis factor signaling pathway, interleukin-17 signaling pathway, and NF-kappaB signaling pathway were important metabolic pathways involved. Conclusions The virulence factor Mp1p may affect host macrophages by modulating the tumor necrosis factor signaling pathway, interleukin-17 signaling pathway, and NF-kappaB signaling pathway. The findings contribute to a better understanding of the mechanisms of action of Mp1p and may offer potential directions for the selection of relevant diagnostic and therapeutic targets in the future.

Purpose::Autologous osteoperiosteal transplantation (AOPT) is one of the most feasible and effective techniques for cystic osteochondral lesions of the talus (OLT). However, few reports have been reported about the process of graft-host bone healing and bone articular surface reconstruction, which help us to further understand the actual situation of bone healing and modify surgical methods.Methods::The case series study retrospectively evaluated 33 osteochondral lesions in 30 patients undertaking AOPT for OLT with subchondral cysts from December 2016 to October 2021. According to CT observation, we used 4 variables to describe the bony articular repair, including the integration of the articular surface, the height of the bone filling, the status of bone union, and the appearance of bone resorption or cystic change. We also analyzed the demographic data and clinical function. Descriptive statistics were used for demographic and clinical variables. Normally distributed data were presented as mean ± SD, and non-normally distributed data were presented as median (Q 1, Q 3). Associations between these variables and the primary clinical outcomes were examined using t-test or one-way ANOVA test for continuous variables. Results::The patients’ mean age was (41.7 ± 14.0) years old and the mean follow-up time was (29.6 ± 17.8) months. The chondral lesion size was (14.3 ± 4.1) mm. The cyst depth was (10.9 ± 3.7) mm. Significant improvements were observed in functional outcomes (according to the numeric rating scale for pain when walking and the American orthopedic foot and ankle society score) between the preoperative and latest follow-up evaluations, from 4.2 ± 2.1 to 2.2 ± 2.0 ( p < 0.001), and from 66.8 ± 12.9 to 83.2 ± 10.4, respectively ( p < 0.001). The overall satisfaction reached 8.3 of 10 points. All patients returned to sports and their median daily steps reached 8000 steps with 27 (81.8%) patients walking over 6000 steps daily. According to CT observation, "discontinuous bony articular surface and gap > 1 mm" was found in 27 grafts (81.8%), and "below the level of the adjacent articular surface, ≤1 mm" in a third of the grafts. Abnormal height of bone filling affected numeric rating scale score ( p=0.049) and American Orthopedic Foot and Ankle Society score ( p =0.027). Of note, bone resorption or cystic changes appeared in up to 13 autografts (39.4%). Conclusions::AOPT is an effective and acceptable technique for cystic OLT. Bone reconstruction is essential for large cystic OLT. How to get better bony articular reconstruction and avoid cyst recurrence should still be paid more attention.

Objective:To construct polydopamine-coated silicified collagen(SC@PDA)by polymerization of dopamine,and to ex-plore its biological safety and photothermal antibacterial properties.Methods:Dopamine was coated on the surface of silicified colla-gen by polymerization reaction to construct SC@PDA.The surface morphology of SC@PDA was observed by SEM and TEM,the silic-ic acid release was detected by silicic acid release experiment,and the photothermal properties of SC@PDA were detected by 808 nm laser irradiation and infrared thermography.The biocompatibility of SC@PDA was evaluated by CCK-8 assay with rat bone marrow mesenchymal stem cells and acute systemic toxicity test in SD rats.The materials were co-cultured with Staphylococcus aureus(S.au-reus)and Escherichia coli(E.coli)respectively for 6 h followed by 808 nm laser irradiation and culture for 6 h,and then the antibac-terial rate of the materials was calculated by absorbance detection.Finally,the anti-infection effect was observed 7 days after implan-tation in the rat femoral defect infection model of SD rats.Results:SC@PDA maintained the silicic acid release characteristics of si-licified collagen and had good biocompatibility and good photothermal property.In vitro and in vivo antibacterial experiments showed that SC@PDA had good antibacterial activity without cytotoxicity and acut system toxicity.Conclusion:SC@PDA has biocompatibili-ty and the dopamine coating endows the silicified collagen scaffold with excellent photothermal antibacterial properties.