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.

ObjectiveTo investigate the regulatory effect of overexpressed protein tyrosine phosphatase non-receptor type 2 （Ptpn2） on the inflammatory response of mouse alveolar macrophages （MH-S） induced by SiO₂. MethodsCells with overexpressed Ptpn2 were constructed and induced by SiO₂. The experimental groups were divided into four groups： the negative control group with an empty vector （NC）， the overexpressed Ptpn2 group （P）， the negative control group with an empty vector + SiO₂ induction （NS）， and the overexpressed Ptpn2 + SiO₂ induction group （PS）. Isobaric tags for relative and absolute quantification （iTRAQ） combined with liquid chromatography-tandem mass spectrometry （LC-MS/MS） were used to screen differential proteins， followed by Gene Ontology （GO） and Kyoto Encyclopedia of Genes and Genomes （KEGG） database analyses. Immunofluorescence staining was used to detect the expressions of Tumor necrosis factor （TNF） α， Gasdermin D （GSDMD）， and Transforming growth factor （TGF）-β1. Western blot was used to detect the protein expression levels of PTPN2， Toll-like receptor 4 （TLR4）， tumor necrosis factor-α （TNF-α）， nucleotide-binding oligomerization domain-like receptor protein 3 （NLRP3）， and proteins related to the TGF-β1 signaling pathway in the cells of each group. ResultsiTRAQ results identified 144 differential proteins among the four groups. GO analysis showed that in biological processes （BP）， these differential proteins were mainly enriched in IκB kinase/nuclear factor-κB （NF-κB） signaling， cell activation and signal transduction involved in immune responses， and regulation of receptor signaling pathways by signal transducer and activator of transcription （STAT）， etc. KEGG analysis revealed that the differential proteins were mainly enriched in Toll-like receptor signaling pathway， NF-κB signaling pathway， NOD-like receptor signaling pathway， TGF-β signaling pathway， and TNF signaling pathway. The results of immunofluorescence staining showed that compared with the NC group， the expressions of TNF α， GSDMD， and TGF-β1 in the cells of the NS group increased （P < 0.05）； compared to the NS group， the expression of the aforementioned proteins in the PS group decreased in cellular proteins（P < 0.05）. The results of Western blot showed that compared with the NC group， the protein expression levels of PTPN2， p-NF-κB，MyD88，TLR4，NLRP3，GSDMD，Caspase-1，IL-1β， TGF-βR1， TGF-βR，p-Smad2/3 in the NS group were significantly upregulated （P < 0.05）； compared with the NS group， the expression levels of the aforementioned proteins in the PS group were significantly downregulated （P < 0.05）. ConclusionOverexpression of Ptpn2 can inhibit the protein expressions of TLR4-TNF-α signaling， NLRP3 signaling， and TGF-β1 signaling closely related to inflammatory response in SiO₂-mediated MH-S macrophages.

Objective: To analyze the causes of abnormal blood agglutination caused by high-titer cold antibodies in blood donors from a serological perspective. Methods: The donor's blood type was identified using the tube method. Direct antiglobulin test (DAT), indirect antiglobulin test (IAT), and antibody titer detection were performed on the samples. Results: The blood type of the donor was type B, and the DAT was negative. No complement components were detected on the surface of the donor's red blood cells. The supernatant of the suspended red blood cells was clear without abnormal coloration, and the agglutinated clumps were intact and difficult to dissociate. The antibody was identified as an IgM-type anti-IH cold agglutinin. At 4℃, this antibody reacted with autologous red blood cells, adult group B red blood cells, adult group O red blood cells, cord blood group B red blood cells and cord blood group O red blood cells, with a stronger reaction intensity observed with group O cells than with B cells. The titers were 512, 128, 256, 32 and 128, respectively. Conclusion: High-titer anti-IH can cause abnormal agglutination of blood at low temperatures. During blood distribution and clinical use, the appearance of blood products shall be strictly inspected to prevent the release of non-conforming blood products.

ObjectiveBiochemistry and Molecular Biology, a discipline that elucidates life phenomena at the molecular level, serves as a core foundational course in medical education. It provides the theoretical basis for studying other basic and clinical medical subjects, as well as for understanding pathogenesis, disease diagnosis, and treatment. However, its complex content and highly abstract concepts have posed a dual challenge to traditional teaching models: “inefficient instruction” and “inadequate learning outcomes”. Within limited classroom hours, how to engage students and stimulate their intrinsic motivation, and how to help them recognize, understand, and develop a passion for biochemistry from the perspective of the discipline’s essence, have long been key focuses of curriculum research. MethodsUsing the lipid metabolism chapter as an example, this study employs “Rain Classroom”, a generative artificial intelligence (AI)-assisted platform, to support education in four dimensions: teaching, learning, evaluation, and research. In teaching, it assists instructors through virtual experiments, lesson preparation support, knowledge mapping, and assignment design. For learning, it serves as an intelligent study assistant for students, providing automated assignment review, enabling educational resource sharing, and facilitating personalized learning pathways. In evaluation, the platform automates assignment grading, analyzes student performance data, and offers diagnostic feedback and teaching recommendations. In research, it aids educators in collecting and analyzing teaching data, as well as searching for and summarizing relevant literature. ResultsThe results indicate that an educational model integrating teacher-led instruction, student-centered learning, and generative AI assistance significantly enhances teaching quality, students’ self-directed learning abilities, and knowledge mastery. Furthermore, with the support of generative AI, curriculum-based ideological education—focusing on cutting-edge disciplinary advances and topical medical issues—helps cultivate students’ medical spirit of “honoring life and healing the wounded”, thereby fostering the establishment of appropriate professional values. Finally, while generative AI presents both opportunities and challenges for higher education, this study also analyzes potential risks in its teaching applications, emphasizing the need for both instructors and students to avoid over-reliance and to ensure that technological tools consistently serve the fundamental goals of education. ConclusionThis study demonstrates that integrating generative AI, specifically via the “Rain Classroom” platform, can effectively enhance biochemistry education. By supporting teaching, learning, evaluation, and research, this approach improves both educational effectiveness and student outcomes. It also facilitates the incorporation of cutting-edge knowledge and professional ethics, nurturing a patient-centered mindset. Additionally, the study addresses potential implementation risks to ensure that such technological tools remain aligned with the core purpose of education.

Dry eye disease is a chronic ocular surface disorder of multifactorial origin, characterized by a loss of tear film homeostasis and associated with a range of ocular discomfort symptoms. Growing evidence underscores a significant bidirectional relationship between dry eye and depression: individuals with dry eye disease exhibit a higher prevalence of depressive disorders, and conversely, those diagnosed with depression demonstrate an increased susceptibility to developing dry eye. This interplay is mediated through several pathophysiological pathways, such as chronic inflammation, cerebral functional alterations, gut microbiome dysregulation, and sleep disturbances, which may collectively sustain a vicious cycle. The use of antidepressant therapy introduces further complexity, exerting heterogeneous effects on dry eye—some agents may offer symptomatic relief, whereas others can aggravate ocular surface impairment. The mechanisms responsible for these differential outcomes remain incompletely elucidated and merit further investigation. This review systematically consolidates epidemiological data on the dry eye-depression link, examines potential shared pathological mechanisms, and evaluates current therapeutic options. We propose an integrated management approach that combines conventional dry eye treatments, such as traditional Chinese medicine, electroacupuncture, physical activity and antidepressants—a multimodal strategy that may yield synergistic benefits in alleviating both ocular and affective symptoms, thereby improving overall quality of life. Moving forward, research should focus on deciphering the underlying mechanistic pathways and facilitating the translation of these insights into clinical practice to inform targeted, combined treatment regimens for patients with dry eye and depression.

Objective:To determine the optimal cut-off value of serum cotinine for distinguishing smoking status among Chinese adults based on a large-scale national sample.Methods:A cross-sectional study was conducted among 8 987 Chinese adults aged 20-79 years from 152 administrative counties across 31 provinces during 2017-2018. Sociodemographic characteristics, lifestyle, smoking status, and health status were collected via questionnaires and physical examinations. Blood samples were analyzed for serum cotinine levels using liquid chromatography-mass spectrometry and for blood creatinine levels using the picric acid method. Receiver operating characteristic (ROC) curve analysis was performed with serum cotinine concentration as the test variable and self-reported smoking status as the state variable. The optimal cut-off value was determined based on the maximum Youden′s index, and the bootstrap method was used for repeated sampling (2 000 times) to evaluate the confidence interval of the cut-off value. The net reclassification index (NRI) was used to evaluate the discrimination ability of the cut-off value of this study, the cut-off value of the American population 1 (total population: 3.3 μg/L, men: 4.1 μg/L, women: 3.0 μg/L) and the cut-off value of the American population 2 (the recommended value of the United States Centers for Disease Control and Prevention for the total population: 10.0 μg/L) against the smoking status of the Chinese population. Statistical analyses were conducted using IBM SPSS 27 and Python 3.11, with a significance level of α=0.05.Results:The age of the research subjects was (49.2±15.2) years. Among them, males accounted for 49.8% (4 477); smokers accounted for 28.8% (2 586); the detection rate of serum cotinine was 94.6% (8 501), and the M ( Q1, Q3) concentration of serum cotinine was 0.9 (0.3, 85.4) μg/L. The ROC curve analysis results showed that the cut-off value (95% CI) of serum cotinine in the total population was 8.8 (6.7-11.7) μg/L, with the specificity (95% CI) about 93.6%(92.7%-94.3%), the sensitivity (95% CI) about 91.0%(89.7%-92.3%) and the area under the curve (AUC) (95% CI) about 0.93 (0.92-0.94). The cut-off value (95% CI) of cotinine for males was 17.1 (8.8-21.8) μg/L, with the specificity (95% CI) about 90.7%(87.9%-92.0%), the sensitivity (95% CI) about 89.4%(88.4%-92.2%) and the AUC (95% CI) about 0.92 (0.91-0.93). The cut-off value (95% CI) of cotinine for females was 7.4 (3.3-15.0) μg/L, with the specificity (95% CI) about 95.6%(92.7%-96.8%), the sensitivity (95% CI) about 87.6%(81.6%-92.8%) and the AUC (95% CI) about 0.92 (0.87-0.95). The NRI analysis results showed that compared with the cut-off value of the American population 2, the NRI of this study′s cut-off values in the total population, males and females were 0.020 ( P=0.015), 0.033 ( P=0.015) and 0.011 ( P=0.380), respectively, indicating that this study′s cutoff value could have better classification performance in the total population and males. Compared with the cut-off value of the American population 2, the NRI of the total population in this study was 0.001 ( P=0.285). Conclusion:The serum cotinine cut-off value based on the analysis of large sample data in China is more suitable for distinguishing the smoking status of Chinese adults.

Ligusticum sinense cv.Fuxiong derived from"Xiongqiong",and in the Song Dynasty's Tai Ping Hui Min He Ji Ju Fang,it was already distinguished from Chuanxiong Rhizoma in usage.Doctors in the Ming Dynasty further clarified the differences in efficacy between the two.However,with the widespread circulation of Chuanxiong Rhizoma,Ligusticum sinense cv.Fuxiong gradually became marginalized,serving as a substitute,and is now only cultivated and used in small quantities within Jiangxi Province.This article reviewed the prescriptions and the ancient Chinese medical books that have records of Ligusticum sinense cv.Fuxiong,analyzed its specific applications alongside Chuanxiong Rhizoma in prescriptions and case studies to elucidate their differences in efficacy:Ligusticum sinense cv.Fuxiong is pungent and has strong dispersing power and is good at unblocking meridians and promoting qi circulation,which is suitable for excessive syndromes;Chuanxiong Rhizoma is good at promoting blood circulation and relieving pain,and is good at regulating and nourishing,which is suitable for patients with deficiency syndromes,aiming to provide insights and recommendations for the further development and rational clinical medication of Ligusticum sinense cv.Fuxiong.

Objective:To investigate the impact of virtual navigation bronchoscopy on perioperative information in patients undergoing thoracoscopic pulmonary resection.Methods:Employed three distinct propensity score matching models to effectively address the baseline data disparities among patients undergoing thoracoscopic pulmonary resection. Categorized the patients into two groups: pulmonary wedge resection and pulmonary segmentectomy. Compared the disparities in clinical characteristics, intraoperative lesion resection, and postoperative recovery between patients who underwent virtual navigation bronchoscopy assisted localization prior to surgery and those who did not employ any specific localization methods.Results:This reserch included a total of 127 patients who underwent localization assisted by virtual navigation bronchoscopy, and 122 patients who did not undergo specialized localization. After propensity score matching, the navigation group demonstrated a statistically significant reduction in intraoperative blood loss[model 3, 40(20, 50) ml vs. 50(20, 100) ml, P=0.027], drainage volume on the first day post-surgery[model 3, 100(50, 175) ml vs. 150(100, 220) ml, P=0.023], and incidence of residual pleural effusion(model 3, 31 cases vs. 38 cases, P=0.046) compared to the non-positioning group among patients undergoing pulmonary wedge resection. In the pulmonary segmentectomy group, we observed a reduction in intraoperative blood loss[model 3, 50(30, 100) ml vs. 100(50, 100) ml, P=0.003] and incidence of residual pneumothorax(model 3, 18 cases vs. 28 cases, P=0.012) in patients who underwent navigation-assisted procedures compared to those without specialized positioning. Conclusion:The utilization of virtual navigation bronchoscopy for preoperative localization assistance in thoracoscopic sublobectomy(including wedge resection and segmental resection) may represent a viable approach to mitigate intraoperative injury and facilitate postoperative recovery.

Objective To observe the value of deep learning(DL)reconstruction algorithm for improving imaging quality of accelerated T2WI of cervical tumors.Methods A total of 43 patients with suspected cervical tumors were prospectively enrolled.Cervical conventional T2WI and accelerated T2WI based on DL reconstruction(DL-T2WI)were acquired.The imaging quality was subjectively assessed by 2 physicians using a 4-point system,including overall image quality,artifact,noise,sharpness and lesion detectability scores,and then were compared between conventional T2WI and DL-T2WI.Results The acquisition of conventional T2WI took 116 s,while of DL-T2WI took 101 s.The inter-observer consistency of subjective evaluation results on the overall image quality,artifact,noise,sharpness and lesion detectability scores were all excellent(Kappa=0.851-0.969).No significant difference of subjective evaluation results on overall image quality nor lesion detectability scores was found between conventional T 2WI and DL-T2WI(both P＞0.05),while the artifact and sharpness scores of DL-T2WI were significantly higher but the noise score was significantly lower than those of conventional T2WI(all P＜0.05).Conclusion DL reconstruction algorithm was helpful for improving imaging quality of accelerated T 2WI of cervical tumors.

AIM To establish the near-infrared spectroscopy quantitative models for moisture,23-acetylalismol B and 23-acetylalismol C in Alismatis Rhizoma decoction pieces.METHODS The near-infrared spectroscopy(NIRS)data were collected in 95 batches of decoction pieces,after which drying method was adopted in the content determination of moisture,HPLC was applied to determining the contents of 23-acetylalismol B and 23-acetylalismol C,the quantitative models were established by partial least squares method combined with feature extraction algorithms.RESULTS The model training determination coefficients were 0.952 6,0.958 1 and 0.920 8,along with the prediction determination coefficients of 0.930 0,0.905 2 and 0.906 4,the residual prediction deviations(PRD)of 4.00,3.58 and 3.46,and the root mean square error ratios of prediction values to calibration values(RMSEP/RMSEC)of 1.15,1.11 and 1.06,respectively.CONCLUSION The quantitative models based on NIRS exhibit good prediction effects,which can be used for the rapid quality detection of Alismatis Rhizoma decoction pieces.