Radiotherapy is a crucial treatment modality for head and neck tumors. However, while effectively killing tumor cells, it significantly disrupts the homeostasis of the oral microecology, which is closely associated with various complications such as radiation-induced oral mucositis. Literature review indicates that as radiotherapy doses accumulate and treatment durations extend, the richness and diversity of the oral microbiota show a declining trend, with the genus Streptococcus decreasing most markedly. In contrast, radiotherapy selectively promotes the proliferation of bacterial phyla such as Proteobacteria and Bacteroidetes, which are rich in opportunistic pathogens. Mechanistically, radiotherapy activates the nuclear factor-kappa B pathway, triggering chronic inflammation and oxidative stress, damaging the epithelial barrier, suppressing local immunity, and causing damage to organs such as the salivary glands. It can also induce systemic diseases via the oral-gut axis, forming a multi-level, interconnected pathogenic network. In terms of interventions, treatment strategies including probiotics and prebiotics have shown promising efficacy against side effects such as radiation-induced oral mucositis. Saliva-based oral microbiota transplantation is an emerging strategy that is expected to become widely utilized for restoring oral microecological balance. Existing interventions provide preliminary pathways for clinical practice, but this field still faces several key scientific questions. The association between oral microecology and systemic diseases remains largely correlative, lacking causal evidence. Furthermore, critical parameters for oral microbiota transplantation, such as donor screening criteria, transplantation protocols, and long-term safety, are not yet well-defined. Therefore, future research should focus on conducting large-scale clinical trials to establish standardized protocols and safety evaluation systems for oral microecological interventions, and explore combined treatment therapies such as probiotics, prebiotics, and microbiota transplantation to advance the development of personalized precision modulation. These will enable more effective management of radiotherapy-induced oral microecological dysbiosis and improve treatment outcomes and quality of life for patients with head and neck tumors.

Laboratory animals serve as the cornerstone in life science research, acting as surrogate models for human physiology, pathology, and disease treatment. They play an irreplaceable role in basic research, drug development, and translational medicine. Gut microbiota, a complex microbial community comprising bacteria, fungi, viruses, and unicellular organisms, colonizes the host's intestinal tract and is closely associated with the maintenance of normal physiological metabolism and overall health. Studies have shown that dysbiosis of the gut microbiota can lead to various diseases, including obesity, diabetes, hypertension, inflammatory bowel disease, and Alzheimer's disease. Therefore, conducting characteristic analyses of the gut microbial composition of laboratory animals can not only enhance the reliability of experimental outcomes but also facilitate their translational application. Sex differences represent a critical variable in biological research, significantly influencing the physiological functions, metabolic traits, and gut microbial composition of laboratory animals. However, a pronounced sex bias has been widely observed in many biological studies, thereby limiting the generalizability of results. This study focused on ten commonly used laboratory animals in life sciences, including mice, rats, guinea pigs, hamsters, rabbits, dogs, cats, non-human primates, miniature pigs, and chickens. Their gut microbial composition was summarized and related sex-specific differences of certain species were analyzed. Furthermore, by comparing the gut microbiota of laboratory animals with that of humans, this study offers novel perspectives for comparative medical research. In summary, this study not only deepens researchers' understanding of gut microbiota characteristics and sex-dependent variations across laboratory animal species but also provides practical guidance for selecting appropriate laboratory animals, constructing sex-specific disease models, and interpreting experimental results in scientific studies.

Laboratory animals serve as the cornerstone in life science research, acting as surrogate models for human physiology, pathology, and disease treatment. They play an irreplaceable role in basic research, drug development, and translational medicine. Gut microbiota, a complex microbial community comprising bacteria, fungi, viruses, and unicellular organisms, colonizes the host's intestinal tract and is closely associated with the maintenance of normal physiological metabolism and overall health. Studies have shown that dysbiosis of the gut microbiota can lead to various diseases, including obesity, diabetes, hypertension, inflammatory bowel disease, and Alzheimer's disease. Therefore, conducting characteristic analyses of the gut microbial composition of laboratory animals can not only enhance the reliability of experimental outcomes but also facilitate their translational application. Sex differences represent a critical variable in biological research, significantly influencing the physiological functions, metabolic traits, and gut microbial composition of laboratory animals. However, a pronounced sex bias has been widely observed in many biological studies, thereby limiting the generalizability of results. This study focused on ten commonly used laboratory animals in life sciences, including mice, rats, guinea pigs, hamsters, rabbits, dogs, cats, non-human primates, miniature pigs, and chickens. Their gut microbial composition was summarized and related sex-specific differences of certain species were analyzed. Furthermore, by comparing the gut microbiota of laboratory animals with that of humans, this study offers novel perspectives for comparative medical research. In summary, this study not only deepens researchers' understanding of gut microbiota characteristics and sex-dependent variations across laboratory animal species but also provides practical guidance for selecting appropriate laboratory animals, constructing sex-specific disease models, and interpreting experimental results in scientific studies.

OBJECTIVE To analyze the current status and challenges in importing rare disease drugs in China， providing references for optimizing the import process and improving relevant policies. METHODS Questionnaires and interviews were conducted with stakeholders involved in rare disease drug importation， including government departments， multinational pharmaceutical enterprises， healthcare institutions， and patient organizations. This explored the current situation and challenges encountered by each party. Expert opinions were synthesized to propose improvement suggestions. RESULTS A questionnaire survey of representatives from 25 multinational pharmaceutical companies in the rare disease field revealed that these companies had a strong willingness to import rare disease drugs， with 58.33% of them practicing diverse import models. However， significant challenges hindered this process， including unclear regulations （54.17%）， complex approval procedures （45.83%）， and excessively long approval cycles （41.67%）， negatively impacting their motivation. Meanwhile， interviews with 13 experts from government departments， healthcare institutions， pharmaceutical enterprises， and patient organizations identified deficiencies in policy design， approval processes， sampling inspection costs， and communication efficiency with regulators. Additionally， the drug import model in special medical zones also required improvement. CONCLUSIONS The importation of rare disease drugs in China faces challenges such as incomplete policies， inflexible regulatory mechanisms， and insufficient communication channels. It is recommended to enhance the rare disease definition criteria， optimize import incentive policies， and refine regulatory models， so as to further optimize the import process of rare disease drugs and improve relevant policies.

ObjectiveTo investigate the alleviating effect of calcium cyanamide （CaCN₂） soil fumigation on replanting problems of Rehmannia glutinosa. MethodsNewly soil （NP） was used as the control group， while three treatment groups were established： replanted soil （RP）， newly soil treated with CaCN₂ （120 g·m²， tillage depth 25 cm） （NPCC）， and replanted soil treated with CaCN₂ （RPCC）. R. glutinosa was cultivated in all groups. At harvest， the tuber agronomic traits （number of enlarged roots， maximum root diameter， fresh weight， dry weight） were measured. The content of catalpol and rehmannioside D was quantified by ultra-high-performance liquid chromatography （UPLC） to evaluate medicinal quality. Rhizosphere soil available nutrients and enzyme activities were analyzed by assay kits. The community structure and composition of fungi and bacteria in rhizosphere soil were assessed via internal transcribed spacer 2 （ITS2） sequencing and 16S rDNA sequencing， respectively. ResultsCompared with NP， the RP group showed obviously reduced in tuber agronomic traits and quality indicators （P0.05）. However， the RPCC group showed significant improvement in agronomic traits and a notable increase in rehmannioside D content compared to RP （P0.05）. The contents of available phosphorus and potassium in RPCC and NP groups were obviously lower than those in RP （P0.05）. The polyphenol oxidase soil （S-PPO） activity in RP was obviously lower than in NP （P0.05）， while sucrose soil （S-SC）， acid phosphatase soil （S-ACP）， and S-PPO activities in RPCC were obviously higher than in RP （P0.05）. Microbial richness and diversity in RP were obviously higher than in NP （P0.05）， whereas no significant differences were observed between the RPCC and NP. The relative abundances of fungal genera Nectria， Myrothecium， Tomentella， and bacterial genus Skermanella were obviousl lower in RPCC and NP than in RP （P0.05）. Correlation analysis that S-ACP activity was positively correlated with the content of rehmannioside D （P0.05）. Fungal genera Engyodontium and Alternaria， and bacterial genera Pir4 lineage， Pirellula， Methyloversatilis， Brevundimonas， Ralstonia， and Acidibacter were obviously positively correlated with tuber dry weight （P0.05）. Conversely， fungal genera Pseudaleuria， Nectria， Haematonectria， Ceratobasidium， and bacterial genera Streptomyces， Skermanella， RB41， Gemmatimonas， and Bacillus were obviously negatively correlated with dry weight （P0.05）. The fungal genus Alternaria and bacterial genera Brevundimonas， Ralstonia， Acidibacter， and Dongia showed positive correlations with medicinal quality of R.glutinosa tuber， while fungal genera Pseudaleuria， Nectria， Stachybotrys， Fusarium， Gibberella， Ceratobasidium， and bacterial genera Sphingomonas， Skermanella， RB41， Gemmatimonas， and Bacillus were obviously negatively correlated （P0.05）. ConclusionCaCN₂ soil fumigation can significantly improve enzyme activities in replanted Rehmannia rhizosphere soil， enhance the utilization of available nutrients， reshape microbial community structure of replanted R.glutinosa at the family and genus level， and notably improve tuber agronomic traits and medicinal quality. This study provides a novel approach to alleviating replanting problems and offers insights for the integrated development of standardized cultivation techniques， including soil disinfection， nutrient-targeted regulation， and microbial inoculant application.

Protein arginine methyltransferase 5 (PRMT5) acts as an oncogene in liver cancer, yet its roles and in-depth molecular mechanisms within the liver cancer immune microenvironment remain mostly undefined. Here, we demonstrated that disruption of tumor-intrinsic PRMT5 enhances CD8⁺ T-cell-mediated antitumor immunity both in vivo and in vitro. Further experiments verified that this effect is achieved through downregulation of the inhibitory immune checkpoint molecule, fibrinogen-like protein 1 (FGL1). Mechanistically, PRMT5 catalyzed symmetric dimethylation of transcription factor 12 (TCF12) at arginine 554 (R554), prompting the binding of TCF12 to FGL1 promoter region, which transcriptionally activated FGL1 in tumor cells. Methylation deficiency at TCF12-R554 residue downregulated FGL1 expression, which promoted CD8⁺ T-cell-mediated antitumor immunity. Notably, combining the PRMT5 methyltransferase inhibitor GSK591 with PD-L1 blockade efficiently inhibited liver cancer growth and improved overall survival in mice. Collectively, our findings reveal the immunosuppressive role and mechanism of PRMT5 in liver cancer and highlight that targeting PRMT5 could boost checkpoint immunotherapy efficacy.

Mesenchymal stem cells (MSCs) have been widely used in the treatment of various autoimmune and inflammation-related diseases due to their potent immunomodulatory properties. Several studies have demonstrated that MSC-mediated immunomodulation is complex and bidirectional, with the in vivo microenvironment influencing the direction of this modulation. Indoleamine-2,3-dioxygenase (IDO), an immunosuppressive factor, has been identified as a key "switch" in the immunomodulatory role of MSCs. In this review, we explore how IDO functions as a critical regulator of MSC immunoregulatory plasticity. We delve into the mechanisms by which changes in IDO expression affect the function of various immune cells, summarize relevant research and clinical advances regarding the role of IDO expression in MSC-based therapies for various diseases, and discuss potential therapeutic strategies that target IDO to enhance the stability of MSC therapeutic effects. This provides a theoretical foundation for optimizing MSCs as safer and more effective clinical therapeutic agents.

Metabolic reprogramming plays a central role in tumors. However, the key drivers modulating reprogramming of gluconeogenesis/lipogenesis are poorly understood. Here, we try to identify the mechanism by which histone acetyltransferase 1 (HAT1) confers reprogramming of gluconeogenesis/lipogenesis in liver cancer. Diethylnitrosamine (DEN)/carbon tetrachloride (CCl₄)-induced hepatocarcinogenesis was hardly observed in HAT1-knockout mice. Multi-omics identified that HAT1 modulated gluconeogenesis and lipogenesis in liver. Protein phosphatase 2 scaffold subunit alpha (PPP2R1A) promoted gluconeogenesis and inhibited lipogenesis by phosphoenolpyruvate carboxykinase 1 (PCK1) serine 90 dephosphorylation to suppress the tumor growth. HAT1 succinylated PPP2R1A at lysine 541 (K541) to block the assembly of protein phosphatase 2A (PP2A) holoenzyme and interaction with PCK1, resulting in the depression of dephosphorylation of PCK1. HAT1-succinylated PPP2R1A contributed to the remodeling of gluconeogenesis/lipogenesis by PCK1 serine 90 phosphorylation, leading to the inhibition of gluconeogenic enzyme activity and activating sterol regulatory element-binding protein 1 (SREBP1) nuclear accumulation-induced lipogenesis gene expression, which enhanced the tumor growth. In conclusion, succinylation of PPP2R1A lysine 541 by HAT1 converses the role in modulation of gluconeogenesis/lipogenesis remodeling through PCK1 S90 phosphorylation to support liver cancer. Our finding provides new insights into the mechanism by which post-translational modifications (PTMs) confer the conversion of tumor suppressor function to oncogene.