National biological standards for antibiotics are critical components of the antibiotic quality control system and serve as reference materials for measuring and calibrating the biological activity of antibiotics. This article systematically reviews the classification, definition of potency units, and current research status of commercially available national antibiotic biological standards in China. At present, these standards can be categorized based on chemical structure, number of components, and development methods. The definition of potency units has evolved from an early “arbitrarily assigned unit” to “being represented by the mass of the antibiotic salt” and, more recently, to the current mainstream approach of “being represented by the mass of the active ingredient”. This evolution reflects a shift in quality control philosophy from primarily biological analysis to a system dominated by chemical analysis supplemented by biological methods. Current research focuses on optimizing potency determination methods, studying the unification of content and potency, and implementing dual quality control of both the potency and the ratio/content of active components in multi-component antibiotics. For complex multi-component antibiotics, the microbiological assay based on biological activity remains irreplaceable in quality control. Future efforts should emphasize further method optimization, ensuring batch-to-batch consistency of standards, and advancing precision quality control as key research priorities for antibiotic biological standards.

Background/Aims: Natural killer (NK) cell function is generally considered dampened in chronic hepatitis B virus (HBV) infection; however, the NK cell pool exhibits phenotypic and functional heterogeneity, and the antibody--mediated effect of NK cells remains less characterized. This study evaluated the dynamic changes in antibody-mediated NK cell responses and the involvement of distinct NK subsets across disease stages and during antiviral treatment. Methods: A T-cell receptor-like antibody specific for the HBV core 18–27 peptide (cTCRL-Ab) was used to determine the antibody-mediated effect of NK cells, and an array of NK cell surface markers were analyzed in cross-sectional and longitudinal cohorts of patients with chronic HBV infection. Single-cell RNA sequencing (scRNA-seq) was performed to identify the heterogeneity of NK subsets. Results: The cTCRL-Ab enabled the detection of NK cell cytolytic activity and IFNγ production. Notably, cTCRL-Ab-mediated NK cell responses were compromised in chronically HBV-infected patients, particularly in those receiving pegylated interferon-α (Peg-IFNα), which was associated with the downregulation of CD16 expression. Correspondingly, Peg-IFNα inhibited cTCRL-Ab-mediated NK cell function by reducing CD16 expression in vitro. scRNA-seq revealed that CD16 downregulation occurred mainly within a dysfunctional CD16hi NK subset exhibiting exhaustion properties. In contrast, an activated CD16hiNK subpopulation (CX3CR1⁺KLRC2–CD16hi) with high cytotoxicity was enriched in patients who experienced favorable treatment responses. Furthermore, the intrahepatic CX3CR1+KLRC2–CD16hi subset tended to exhibit functional restoration in HBsAg-loss individuals. Conclusions Our data contribute to the understanding of antibody-mediated responses of NK cells in chronic HBV infection, and highlight a previously unappreciated functional CX3CR1+KLRC2–CD16hiNK subset as a potential therapeutic target.

Glycogen synthase 1 (GYS1) is the rate-limiting enzyme responsible for glycogen synthesis in skeletal muscle, heart, brain, and other extrahepatic tissues, playing a central role in systemic energy homeostasis. The human GYS1 gene maps to chromosome 19q13.33, comprises 16 exons, and encodes a 737-amino-acid polypeptide that is highly conserved across mammals. GYS1 activity is subject to multilayered and precisely coordinated regulation. At the transcriptional level, the GYS1 promoter contains a hypoxia response element (HRE) that mediates HIF-1α-dependent induction under low-oxygen conditions, as well as a muscle-specific enhancer harboring MEF2 and MyoD binding sites that confers tissue-restricted expression. At the post-translational level, a hierarchical phosphorylation cascade serves as the primary activity switch: glycogen synthase kinase 3β (GSK3β) sequentially phosphorylates four C-terminal serine residues following casein kinase II priming, while protein kinase A (PKA) and AMP-activated protein kinase (AMPK) provide parallel inhibitory inputs at both N- and C-terminal sites. Dephosphorylation and reactivation are mediated by protein phosphatase 1 (PP1) through tissue-specific glycogen-targeting regulatory subunits such as PPP1R3A and PPP1R3B, which anchor PP1 to glycogen particles and direct its activity toward GYS1. The allosteric activator glucose-6-phosphate (G6P) binds at the dimer interface, simultaneously enhancing catalytic efficiency and promoting dephosphorylation susceptibility, thereby establishing a feed-forward activation loop that couples substrate availability to glycogen synthesis. Beyond phosphorylation, GYS1 is regulated by ubiquitination (mediated by the E3 ligase PJA1), acetylation, O-linked β-N-acetylglucosamine (O-GlcNAc) modification, and SUMOylation, which collectively modulate protein stability, subcellular localization, and protein-protein interactions. Epigenetic mechanisms, including CpG island methylation and histone acetylation dynamics, govern chromatin accessibility at the GYS1 locus, while muscle-specific microRNAs such as miR-1 and miR-206 fine-tune GYS1 expression at the post-transcriptional level. Dysregulation of GYS1 has been identified as a central pathogenic driver in a spectrum of human diseases. In inherited glycogen storage disorders—including Lafora disease, adult polyglucosan body disease (APBD), and Pompe disease—loss of upstream regulatory control leads to GYS1 hyperactivation and the accumulation of structurally abnormal or excessive glycogen, resulting in progressive neurodegeneration, myopathy, and multiorgan dysfunction. In type 2 diabetes mellitus (T2DM), impaired insulin signaling through the PI3K-AKT-GSK3β axis maintains GYS1 in a hyperphosphorylated inactive state in skeletal muscle, compromising postprandial glucose disposal and exacerbating hyperglycemia. In oncology, GYS1 exhibits context-dependent roles across multiple cancer types. In hepatocellular carcinoma, FMO2⁺ cancer-associated fibroblasts stabilize GYS1 by competitively inhibiting PJA1-mediated ubiquitination, and stabilized GYS1 subsequently activates NF‑κB/CCL19 signaling to promote tertiary lymphoid structure formation and enhance anti-PD-1 immunotherapy responsiveness. In clear cell renal cell carcinoma, GYS1 promotes tumor progression through non-canonical NF‑κB pathway activation via the scaffold protein RPS27A. In triple-negative breast cancer, GYS1 has been identified as a trigger of disulfidptosis and an activator of NF-κB signaling through non-enzymatic facilitation of IκBα degradation. In colorectal cancer, mitochondrial fission deficiency drives AMPK-dependent GYS1 upregulation and glycogen accumulation as a compensatory survival mechanism, while in cervical cancer, GYS1-maintained glycogen reserves fuel the pentose phosphate pathway to generate NADPH for ROS clearance, thereby conferring cisplatin resistance in cancer stem cells. Therapeutic strategies targeting GYS1 have gained substantial momentum across these disease contexts. For glycogen storage disorders, antisense oligonucleotides, small interfering RNAs (e.g., ABX1100), and small-molecule inhibitors (e.g., MZ-101) have demonstrated preclinical and early clinical efficacy in reducing pathological glycogen accumulation. For T2DM, pharmacological activation of GYS1 through GSK3β inhibition or enhancement of PP1-mediated dephosphorylation is being explored to restore insulin-stimulated glycogen synthesis. In cancer, GYS1-directed interventions—including targeted silencing to sensitize tumors to chemotherapy and immune microenvironment modulation to enhance immunotherapy—represent emerging precision oncology approaches. This review provides a comprehensive and integrated account of GYS1 gene structure, tissue-specific distribution, regulatory networks, and pathogenic roles in metabolic disorders and malignancies, with the aim of establishing a theoretical framework for the development of GYS1-targeted precision therapies.

Objective To investigate the mechanism of hippocampal neuronal plasticity of newborn neurons in the hippocampus by which exercise improves the fear and anxiety symptoms of post-traumatic stress disorder(PTSD).Methods Totally 40 C57BL/6J male mice were randomly divided into by control group(Ctrl)and PTSD group,the PTSD group was divided into a no-exercise group(PTSD),a low-intensity exercise group(L)and a high-intensity exercise group(H).The PTSD model mice were constructed by combining conditioned plantar-foot shock(CF)and single-session sustained stress(SPS).After the exercise intervention,the fear and anxiety levels of the mice were assessed using the conditioned fear test and the elevated cross maze test;Subsequently,the densities of the newborn mature neurons in dentate gyrus(DG)of hippocampus were detected by immunofluorescent double-labelling staining,and the newborn neuron morphology was marked by injecting retrovirus pRetro-U6-EF1-EGFP-3xFLAG-WPRE in DG of hippocampus to observe its morphology.The morphology of the newborn neurons was labelled to observe their dendritic length and the number of branch points;Meanwhile,the concentration level of adiponctin(APN)in the hippocampal area was determined by ELISA.Results The result showed that both high and low-intensity exercise interventions significantly reduced the freezing time of PTSD mice in the conditioned fear test,and in the elevated cross maze experiment,the residence time and the number of entries in the open arm of the mice in the H group increased significantly compared with those in the PTSD group,while the residence time and the number of entries in the closed arm were significantly reduced.In addition,both high and low-intensity exercise interventions significantly increased the surface density and dendritic length of newborn mature neurons in the hippocampal DG region of PTSD mice,and high-intensity exercise significantly increased the number of dendritic branching points,and the density of newborn mature neurons in the H group was more significantly increased compared with that in the L group.At the same time,the hippocampal APN concentration increased significantly in both L and H groups compared with the PTSD group,and it was more significant in the H group.Conclusion Exercises have an ameliorative effect on anxiety and fear symptoms in PTSD mice,and at the same time,it can increase hippocampal neuroplasticity and adiponctin secretion in PTSD mice,suggesting that the improvement of fear and anxiety symptoms in PTSD by exercise may be related to the increase of hippocampal neuroplasticity and APN secretion,and the improvement effect is better with high-intensity exercise.

Protein tyrosine phosphatase nonreceptor type 2 (PTPN2) is a promising target for sensitizing solid tumors to immune checkpoint blockades. However, the highly polar active sites of PTPN2 hinder drug discovery efforts. Leveraging small interfering RNA (siRNA) technology, we developed a novel glutathione-responsive nano-platform HPssPT (HA/PEIss@siPtpn2) to silence PTPN2 and enhance immunotherapy efficacy in hepatocellular carcinoma (HCC). HPssPT showed potent transfection and favorable safety profiles. PTPN2 deficiency induced by HPssPT amplified the interferon γ signaling in HCC cells by increasing the phosphorylation of Janus-activated kinase 1 and signal transducer and activator of transcription 1, resulting in enhanced antigen presentation and T cell activation. The nano-platform was also able to promote the M1-like polarization of macrophages in vitro. The unique tropism of HPssPT towards tumor-associated macrophages, facilitated by hyaluronic acid coating and CD44 receptor targeting, allowed for simultaneous reprogramming of both tumor cells and tumor-associated macrophages, thereby synergistically reshaping tumor microenvironment to an immunostimulatory state. In HCC, colorectal cancer, and melanoma animal models, HPssPT monotherapy provoked robust antitumor immunity, thereby sensitizing tumors to PD-1 blockade, which provided new inspiration for siRNA-based drug discovery and tumor immunotherapy.

Cardiac fibrosis is characterized by an elevated amount of extracellular matrix (ECM) within the heart. However, the persistence of cardiac fibrosis ultimately diminishes contractility and precipitates cardiac dysfunction. Circular RNAs (circRNAs) are emerging as important regulators of cardiac fibrosis. Here, we elucidate the functional role of a specific circular RNA CELF1 in cardiac fibrosis and delineate a novel feedback loop mechanism. Functionally, circ-CELF1 was involved in enhancing fibrosis-related markers' expression and promoting the proliferation of cardiac fibroblasts (CFs), thereby exacerbating cardiac fibrosis. Mechanistically, circ-CELF1 reduced the ubiquitination-degradation rate of BRPF3, leading to an elevation of BRPF3 protein levels. Additionally, BRPF3 acted as a modular scaffold for the recruitment of histone acetyltransferase KAT7 to facilitate the induction of H3K14 acetylation within the promoters of the Celf1 gene. Thus, the transcription of Celf1 was dramatically activated, thereby inhibiting the subsequent response of their downstream target gene Smad7 expression to promote cardiac fibrosis. Moreover, Celf1 further promoted Celf1 pre-mRNA transcription and back-splicing, thereby establishing a feedback loop for circ-CELF1 production. Consequently, a novel feedback loop involving CELF1/circ-CELF1/BRPF3/KAT7 was established, suggesting that circ-CELF1 may serve as a potential novel therapeutic target for cardiac fibrosis.

OBJECTIVES: To investigate the correlation of PRELID1 with gastric cancer (GC) progression, prognosis, and epithelial-mesenchymal transition (EMT) and the underlying mechanisms. METHODS: We analyzed the data of 115 patients undergoing radical gastrectomy for GC in our hospital between February, 2018 and March, 2023 to explore the correlation of PRELID1 expression level in GC tissues with tumor progression and patient prognosis. In cultured GC cells, the effects of lentivirus-mediated overexpression or interference of PRELID1 were observed on cell migration, invasion and EMT. RESULTS: Immunohistochemical staining revealed significantly higher PRELID1 expression in GC tissues (P<0.001), whose expression level was positively correlated with CEA ≥5 ng/mL (P=0.007), CA199 ≥37 U/mL (P=0.007), G_3-4 stages (P=0.001), T_3-4 stages (P=0.001), and N_2-3 stages (P=0.020). Univariate and Cox multifactorial analysis showed that high PRELID1 level was an independent risk factor affecting 5-year survival of GC patients (P=0.001). In cultured GC cells, PRELID1 overexpression obviously promoted cell proliferation, migration, invasion, and the expressions of MMP2 and MMP9, and interference of PRELID1 produced the opposite changes. PRELID1 overexpression also increased the expressions of N-cadherin and vimentin and reduced the expression of E-cadherin. Mechanistic analyses showed that up-regulation of PRELID1 increased the expression of p-PI3K, p-AKT, and p-mTOR in GC cells, whereas its interference caused the opposite changes; the application of 740 Y-P, a PI3K/AKT pathway activator, significantly enhanced the migration, invasion, and EMT of GC cells with PRELID1 knockdown. CONCLUSIONS PRELID1 is highly expressed in GC and affects prognosis of the patients, and its high expression promotes migration, invasion and epithelial mesenchymal transition of GC cells possibly by activating the PI3K/AKT/mTOR pathway.
Humans ; Stomach Neoplasms/metabolism* ; Epithelial-Mesenchymal Transition ; Prognosis ; Cell Movement ; Cell Line, Tumor ; Male ; Female ; Middle Aged ; Signal Transduction ; Neoplasm Invasiveness ; Phosphatidylinositol 3-Kinases/metabolism* ; Proto-Oncogene Proteins c-akt/metabolism*

With the growing emphasis on maternal and child oral health, the significance of managing oral health across preconception, pregnancy, and infancy stages has become increasingly apparent. Oral health challenges extend beyond affecting maternal well-being, exerting profound influences on fetal and neonatal oral development as well as immune system maturation. This expert consensus paper, developed using a modified Delphi method, reviews current research and provides recommendations on maternal and child oral health management. It underscores the critical role of comprehensive oral assessments prior to conception, diligent oral health management throughout pregnancy, and meticulous oral hygiene practices during infancy. Effective strategies should be seamlessly integrated across the life course, encompassing preconception oral assessments, systematic dental care during pregnancy, and routine infant oral hygiene. Collaborative efforts among pediatric dentists, maternal and child health workers, and obstetricians are crucial to improving outcomes and fostering clinical research, contributing to evidence-based health management strategies.
Humans ; Pregnancy ; Female ; Infant ; Consensus ; Mouth Diseases/therapy* ; Pregnancy Complications/therapy* ; Oral Health ; Infant, Newborn ; Delphi Technique ; Oral Hygiene

Drug toxicity is closely related to both clinical drug safety and new drug development. Therefore, it is vital to understand the mechanisms of drug toxicity fully and to use appropriate research models with advanced technologies. Zebrafish has become an important vertebrate animal model for high-throughput drug screening and toxicity assessment. At the same time, zebrafish has an intact biological complexity, reflecting the whole organism's toxicity, which gives it an advantage over other high-throughput models in toxicity studies. Despite the gradual increase in toxicity studies utilizing zebrafish, a comprehensive and systematic review of the underlying mechanisms and new techniques is still lacking. This review aims to analyze common toxicity mechanisms in zebrafish models, such as oxidative stress, endoplasmic reticulum stress, inflammation, and apoptosis, and macroscopic changes in biological processes like lipid metabolism disorders and neurotransmitter expression abnormalities. It also introduces new technologies applied in toxicity assessment, such as gene editing, novel fluorescence imaging technology, 3D imaging technology, and novel automated technology for high-throughput screening, such as fish capsules. In addition, it also summarizes the advantages and disadvantages of the model. By doing so, it will provide new suggestions for the development and improvement of the model, make it better serve the toxicity study of clinical drugs and provide a more comprehensive perspective for drug toxicity study, thus promoting the development of the field of drug toxicity study.

Prone position ventilation (PPV) has been widely used in the treatment strategy of patients with acute respiratory distress syndrome (ARDS). Patients undergoing PPV may develop facial edema and are at risk for pressure injuries due to prolonged prone positioning. In clinical practice, preventive measures such as repositioning, protective dressings, and pressure-relief cushions are commonly used to prevent pressure injuries. However, factors such as improper endotracheal tube placement, self-paid dressings, and delayed clearance of oral and nasal secretions have reduced the effectiveness of preventing facial pressure injuries. To address the above issues, a device for preventing pressure injuries on the faces of patients in the prone position was designed by healthcare workers in the nursing department of Dalian Friendship Hospital, and a National Utility Model Patent of China was obtained (ZL 2024 2 0340439.8). The device consists of a support plate and a circuit control system. The support plate is equipped with two support members. Support member 1 is directly fixed to the support plate, while support member 2 is connected to the support plate via a slide and a spiral rod, serving to support the patient's face and allowing for adjustment of the appropriate width according to the size of the patient's face. Inside the two support members, there are several telescopic rods, with the upper ends designed as spherical supports. The height and position of the telescopic components can be adjusted through a circuit control system, regularly changing the pressure distribution on the patient's face, thereby achieving the purpose of changing the pressure points on the face. The inner wall of support member 2 is equipped with a camera, allowing direct observation of the patient's facial condition through a monitor, avoiding compression of the eyes and nose, and promptly removing secretions from the mouth to keep the face clean, thereby reducing the risk of facial pressure-related injuries. The center of the two support members features a hollow slot, facilitating the placement of a tracheal tube. The circuit control system includes a random module, a time setting module, a control module, and a drive module. Parameters can be set as needed. When the shortest set time is reached, the random module and time setting module send instructions to the control module. Upon receiving the instructions from the time setting module and the random number from the random module, the control module transmits information to the drive module. The drive module, upon receiving the information, controls multiple telescopic rods to adjust their height and position, thereby changing the support points on the patient's face. The device features a simple structure and convenient operation, allowing for flexible adaptation to the patient's facial shape. It can be replaced with the patient's facial pressure area, providing an intuitive view of the patient's facial pressure situation. With automation and high safety, it helps reduce the risk of pressure-related injuries and lightens the workload of medical staff.
Humans ; Pressure Ulcer/prevention & control* ; Prone Position ; Equipment Design ; Facial Injuries/prevention & control* ; Respiration, Artificial/instrumentation* ; Respiratory Distress Syndrome/therapy*