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 inhibitory effect of antimicrobial peptide WK-13-3D on the proliferation of triple negative breast cancer MDA-MB-231 cells and its potential mechanism.Methods The effect of antimicrobial peptide WK-13-3D at concentrations of 0,10,15,20,25,30,35,and 40 μmol/L on MDA-MB-231 cells proliferation was assessed using the CCK-8 assay.A pull-down assay was conducted to identify interacting proteins of antimicrobial peptide WK-13-3D with MDA-MB-231 cells.MDA-MB-231 cells were obtained and divided into the following groups:(1)control group and treatment groups with 10 and 20 μmol/L antimicrobial peptide WK-13-3D.Apoptosis was evaluated using flow cytometry and Western blotting was conducted to detect the expression change of heavy chain binding protein(BiP),protein kinase R-like endoplasmic reticulum kinase(PERK),eukaryotic translation initiation factor 2α(eIF2α),phosphorylated eIF2α(p-eIF2α),and Bax proteins within the cells.(2)Control group(transfected with no-load plasmid),si-BiP-592 group(transfected with si-BiP-592 interference plasmid)and si-BiP-592+WK-13-3D group(co-treated with si-BiP-592 interference plasmid and 10 μmol/L antimicrobial peptide WK-13-3D).Western blotting was used to detect the expression changes of BiP,PERK,eIF2α,p-eIF2α and Bax proteins.Twelve BALB/c mice were randomly divided into PBS group(n=4),taxol(TAX)group(n=4)and WK-13-3D group(n=4).All mice were subcutaneously injected with MDA-MB-231 cells to establish a triple-negative breast cancer transplant tumor model.WK-13-3D group received local injections of antimicrobial peptide WK-13-3D[200 mg/(kg·d)],TAX group was administered TAX intraperitoneally at the same dose[200 mg/(kg·d)],and PBS group was injected with an equivalent volume of PBS.Two weeks post-injection,the mice were killed,and the tumor weight and volume were measured and photographed.Immunohistochemistry staining was performed to evaluate the expressions of BiP and Ki-67 proteins in the tumor tissues.Results CCK-8 assay showed a gradual decrease in MDA-MB-231 cell survival rates with increasing concentrations of WK-13-3D,with an inhibitory concentration 50(IC50)of 19.82 μmol/L.The pull-down assay identified 268 interacting proteins of antimicrobial peptides and MDA-MB-231 cells,mainly including heavy-chain binding protein(BiP),heat shock protein 90 beta family member 1(HSP90B1),valerin-containing protein(VCP),heat shock cognate 71 kD protein(HSPA8).Compared with control group,treatment with 10 and 20 μmol/L antimicrobial peptide WK-13-3D significantly increased the apoptosis rate of MDA-MB-231 cells(P<0.05 or P<0.01),decreased BiP protein expression(P<0.05),and increased the expression levels of PERK,p-eIF2α,and Bax(P<0.05 or P<0.01),with no significant change in eIF2α protein expression(P>0.05).Compared with control group,si-BiP-592 group showed BiP protein expression significantly decreased(P<0.05),and the expression of PERK,p-eIF2α,and Bax proteins was significantly increased(P<0.05),with no significant change in eIF2α protein expression(P>0.05);Compared with si-BiP-592 group,si-BiP-592+WK-13-3D group showed a decrease in BiP protein expression(P<0.05)and an increase in PERK,p-eIF2α,and Bax protein expression(P<0.05 or P<0.01),with no significant change in eIF2α protein expression(P>0.05).Tumor volumes in mice treated with antimicrobial peptide WK-13-3D and TAX were significantly smaller than those in PBS group(P<0.05),and the immunohistochemical staining showed that the proportion of Ki-67 and BiP positive cells in tumor tissues of WK-13-3D treated mice was significantly lower than that in PBS group(P<0.01).Conclusion Antimicrobial peptide WK-13-3D could inhibit the proliferation of MDA-MB-231 cells and its mechanism may involve the activation of endoplasmic reticulum stress and the induction of cell apoptosis.

Objective To comparatively analyze the clinical characteristics of primary bilateral macronodular adrenal hyperplasia(PBMAH)and adrenal cortisol-producing Adenoma(CPA),and enhance the understanding of two diseases.Methods The clinical data of 85 PBMAH patients(PBMAH group)and 195 CPA patients(CPA group)diagnosed at Department of Endocrinology,the First Medical Center of Chinese PLA General Hospital,from September 2014 to August 2024 were retrospectively analyzed.The demographic characteristics,comorbidities,biochemical indicators,adrenocorticotropic hormone-cortisol(ACTH-F)levels,and adrenal imaging features and treatment conditions were compared between the two groups.Results(1)General characteristics:Compared with CPA group,PBMAH group had older age at diagnosis and a higher proportion of male patients.(2)Clinical characteristics:Compared with CPA group,PBMAH group had a longer disease duration,a higher proportion of subclinical Cushing's syndrome(CS),and a higher proportion of hypertension,impaired glucose tolerance/diabetes,bone mass reduction or osteoporosis,with higher serum potassium levels,and the differences were statistically significant(P<0.01).(3)Hormone levels:Both PBMAH and CPA groups showed ACTH-F rhythm disorder,significantly increased cortisol levels and suppressed ACTH.Compared with PBMAH group,CPA group had stronger autonomous cortisol secretion ability,manifested by increased midnight serum cortisol(F0:00),16:00 serum cortisol(F16:00),24-hour urinary free cortisol(24 h UFC)levels and lower 8:00 serum ACTH(ACTH8:00)and 16:00 serum ACTH(ACTH16:00)(P<0.01).After low-dose dexamethasone suppression test(LDDST),CPA group showed lower suppression rates of ACTH and cortisol,and higher proportions of paradoxical elevation in serum cortisol and 24 h UFC compared with PBMAH(P<0.01).Conclusions PBMAH has a longer disease course and higher proportions of comorbid metabolic disorders than CPA,mostly manifested as subclinical Cushing's syndrome.CPA has stronger autonomous cortisol secretion ability,with cortisol less likely to be suppressed after LDDST and more obvious paradoxical elevation of cortisol and 24 h UFC.

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.

Abstract To explore the mechanism of the impact of small games (SSG) on the physical health of children and adolescents and the reasonable application strategies, the study reviewes the multi-dimensional effects of SSG on the body composition, motor ability, cardiovascular health, musculoskeletal health and metabolic health of children and adolescents, and proposes the strategies for the reasonable application of SSG, which include scientifically designing training programs, emphasizing individualized differences, and strengthening monitoring and feedback. It can provide theoretical support and practical suggestions for the application of SSG in promoting the physical health of children and adolescents.

Objective To evaluate the value of left ventricular(LV)systolic function impairment in patients with different activity levels of systemic lupus erythematosus(SLE)by applying automatic myocardial motion quantification(aCMQ)technique,and to explore the correlation between left ventricular strain parameters and clinical laboratory indexes,systemic lupus erythematosus disease activity index(SLEDAI).Methods A total of 80 patients diagnosed with SLE from November 2023 to August 2024 in the First Afticiated Hospital of Jinzhou Medical University were selected and divided into two groups:40 cases with SLEDAI＜10points were in mild lupus group,34 cases with SLEDAI ≥ 10points were in moderately severe lupus group.Forty healthy volunteers for physical examination at the same time were randomly selected as control group,relevant parameters were obtained by conventional echocardiography and aCMQ technique respectively.Results aCMQ technique related parameters were compared,and the differences in left ventricular global longitudinal strain(LVGLS),apical two-chamber longitudinal strain(AP2LS),apical three-chamber longitudinal strain(AP3LS),and apical four-chamber longitudinal strain(AP4LS)were statistically significant in all three groups(P＜0.05).The differences in left ventricular global circumferential strain(LVGCS)in lupus moderate-severe group were statistically significant when compared with other two groups(P＜0.05),Pearson correlation analysis showed LVGLS,AP2LS,AP3LS,AP4LS and LVGCS were positively correlated with complement 3 and complement 4,and negatively correlated with anticardiolipin antibody(ACA)IgA,IgG,IgM,and sedimentation,and ultrasensitive C-reactive protein,and the SLEDAI was correlated with LVGLS,AP2LS,AP3LS,AP4LS were negatively correlated,and there was no significant correlation with LVGCS.Conclusion aCMQ technique can detect changes in LV systolic function in SLE patients at an early stage,and the impairment of LV systolic function is more severe with higher disease activity.Better correlation between LV strain parameters and clinical laboratory indexes and SLED AI may help to better assess cardiac involvement in SLE patients.

Chrysophanol(Chr)and physcion(Phy)are primary active ingredients of a well-known traditional Chinese medicine namely rhubarb(Chinese name:Dahuang),and their glucuronides have been revealed as the dominant forms presenting in rats after oral administration.Either Chr or Phy has two glycosylation sites,resulting in a pair of positional isomers for glucuronides of either compound(CG1&CG2 and PG1&PG2).To confirmatively identify these glucuronides,energy-resolved mass spectrometry(ER-MS)was used to pursue the fragmentation trajectories of the targeted fragment ions,and the resultant breakdown graphs that were described by the optimal collision energy(OCE)were expected to exhibit the differences of glycosidic bond cleavage between the isomers.Quantum chemical calculation was thereafter conducted to produce the bond dissociation energy(BDE)of the glycosidic bonds.The isomers were unambiguously identified through applying the positive correlation rule between OCE and BDE.Fortunately,the glucuronides of Chr and Phy in vivo were observed through liver microsomes incubationin vitro.ER-MS was utilized to collect the Gaussian-shaped breakdown graphs in response to the neutral loss of 176 Da,and the absolute values of OCE were compared between positional isomers.The results revealed that CG1(-32.31 eV)>CG2(-31.61 eV),and nonetheless,PG1(-30.00 eV)Chr-8-GluA(-48.787 kJ/mol),and nonetheless,Phy-1-GluA(-48.672 kJ/mol)

Objective:To explore the diagnostic value of preoperative diffusion weighted imaging (DWI) histogram parameters in the depth of invasion of early rectal cancer.Methods:A total of 180 patients with early rectal cancer admitted to 904th Hospital of Joint Logistics Support Force of Chinese People's Liberation Army from August 2020 to August 2024 were selected as the study objects. Patients were divided into intramucosal cancer group ( n=102) and submucosal cancer group ( n=78) according to the depth of tumor invasion. The general data of the two groups were compared. The intraclass correlation coefficient (ICC) was used to analyze the consistency of DWI histogram parameters extracted by the two radiologists, and the differences between the two groups were compared. Receiver operator characteristic (ROC) curve was used to analyze the predictive value of each parameter to the depth of tumor invasion. Multivariate logistic regression was used to analyze the independent influencing factors of invasion depth, and a predictive model was constructed. The ROC curve was drawn to analyze the predictive value of the model for tumor invasion depth, and the Hosmer-Lemeshow test was used to analyze the goodness of fit of the model. Results:There were statistically significant differences in age ( t=8.15, P<0.001), maximum tumor diameter ( χ2=29.29, P<0.001), endoscopic type ( χ2=20.96, P<0.001), histological type ( χ2=24.93, P<0.001) and differentiation degree ( χ2=73.35, P<0.001) between intramucosal cancer group and submucosal cancer group. The mean, variance, skewness, kurtosis, the 1 st, 10 th, 50 th, 90 th, and 99 th percentiles of the histogram parameters of DWI had good consistency (all ICC>0.75). There were statistically significant differences in the mean ( t=5.69, P<0.001), variance ( t=9.75, P<0.001), skewness ( t=10.88, P<0.001), kurtosis ( t=10.06, P<0.001), the 1 st percentile ( t=3.43, P<0.001), 10 th percentile ( t=3.59, P<0.001), 50 th percentile ( t=9.97, P<0.001), 90 th percentile ( t=4.63, P<0.001), and 99 th percentile ( t=2.44, P=0.016) of the DWI histogram parameters between the intramucosal cancer group and the submucosal cancer group. ROC curve analysis results showed that mean [area under the curve (AUC) =0.77], variance (AUC=0.88), skewness (AUC=0.88), kurtosis (AUC=0.78), 50 th percentile (AUC=0.86) and 90 th percentile (AUC=0.82) had certain diagnostic value for submucous cancer. Multivariate analysis showed that age ( OR=9.98, 95% CI: 1.10-90.70, P=0.041), maximum tumor diameter ( OR=7.36, 95% CI: 1.08-50.23, P=0.042), and differentiation degree ( OR=19.88, 95% CI: 1.21-327.92, P=0.037), variance ( OR=16.24, 95% CI: 2.26-116.68, P=0.006), skewness ( OR=21.13, 95% CI: 2.80-59.61, P=0.003), 1 st percentile ( OR=9.78, 95% CI: 1.17-81.76, P=0.035) were independent factors in predicting tumor invasion depth in patients with early rectal cancer. The predictive model based on the above indicators was logit ( P) =1.51+2.30×age+2.00×maximum tumor diameter+2.99×differentiation degree+2.79×variance+3.05×skewness+ 2.28×the 1 st percentile. ROC curve analysis showed that the predictive model had an AUC of 0.97 (95% CI: 0.95-0.99) for judging the occurrence of submucosal cancer in patients with early rectal cancer, the sensitivity was 0.95, and the specificity was 0.88. The Hosmer-Lemeshow test results showed that the goodness of fit of the model was ideal ( P=0.823) . Conclusions:Age, maximum tumor diameter, differentiation degree, variance, skewness, and the 1 st percentile are independent factors in predicting tumor invasion depth in patients with early rectal cancer. The predictive model constructed based on these factors can effectively predict the risk of submucosal cancer in patients with early rectal cancer.