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.

Objective To explore the incidence and risk factors of sarcopenia in non-dialysis patients with stage 5 chronic kidney disease (CKD). Methods Non-dialysis stage 5 CKD patients in Jiading District Central Hospital Affiliated Shanghai University of Medicine & Health Sciences from October 2023 to October 2024 were enrolled and divided into the non-sarcopenia group and the sarcopenia group according to lean tissue index (LTI) and handgrip strength (HGS). Demographic data of patients were collected and biochemical indicators were detected. Serum advanced glycation end products (AGEs) were detected by competitive ELISA. Multivariate logistic regression analysis was conducted to analyze the risk factors of sarcopenia in these patients. The diagnostic efficacy of the risk factors was evaluated by the receiver operating characteristic (ROC) curve. Results A total of 102 non-dialysis stage 5 CKD patients with (68.52±7.39) years, were enrolled, including 61 male (59.8%). Among them, 24 were diagnosed with sarcopenia (23.5%). Compared with patients in non-sarcopenia group, patients in sarcopenia group were older and had higher interleukin-6 (IL-6) and AGEs, lower body mass index (BMI) and lower serum albumin (sAlb; P＜0.05). Multivariate logistic regression showed that advanced age (OR＝1.153, 95%CI 1.045–1.273, P＝0.005), higher IL-6 (OR＝1.165, 95%CI 1.042–1.302, P＝0.007)、lower sAlb (OR＝0.675, 95%CI 0.542–0.840, P＝0.001), and higher serum AGEs (OR＝1.105, 95%CI 1.013–1.206, P＝0.024) were independent risk factors of sarcopenia in non-dialysis CKD 5 patients. The areas under the curve (AUC) for the age, IL-6, sAlb, and serum AGEs were 0.896, 0.643, 0.658, and 0.724, respectively. Conclusions Sarcopenia is common in non-dialysis stage 5 CKD patients, and the risk of sarcopenia is higher in non-dialysis stage 5 CKD patients with advanced age, higher IL-6, lower sAlb, and higher serum AGEs.

Objective This study reports on the obligatory parasitism of water mites Arrenurus sp. on Anopheles messeae at the Manzhouli Port, Inner Mongolia, China. Methods Duing July 2024, a survey on the mosquito diversity was conducted at the Manzhouli Port. Captured mosquitoes and their ectoparasites were identified to species level. Results A total of 1840 adult mosquitoes were collected, representing species from three genera: Culex(Cx. modestus, Cx. pipiens pallens), Aedes(Ae. dorsalis, Ae. flavidorsalis, Ae. flavescens), and Anopheles (An. messeae). Among all the mosqutioes specimens,3 out of 150 captured An. messeae were found to carry ectoparasitic mites, with number of 2,4,27 mites separately. Morphological and molecular identification reached the same result as water mites(Hydrachnidiae, Hydracrina). COI gene sequence showed 94% similarity with the closest species Arrenurus truncatellus. Conlusions Literature review suggests water mites are host-specific parasitism of mosquito species and herein with the first record of Arrenurus sp. parasiting on An. Messeae in the most high-latitude region globally.

ObjectiveTo address the key challenges in breast electrical impedance tomography (EIT) reconstruction including the severe ill‑posedness of the inverse problem, limited measurement information from the electrodes, low contrast of small lesions, as well as the common drawbacks of traditional reconstruction methods such as boundary blurring, low spatial resolution, and weak small-target detection capability, and to overcome the limitations of existing deep learning approaches namely low training efficiency, insufficient physical consistency, and substantial information loss during the low‑to‑high dimensional mapping process, this study proposes a multi‑scale attention and dynamic sparse mask fusion network (MADS‑Net). The proposed method aims to enhance high‑resolution reconstruction accuracy, small-lesion detectability, noise robustness, and computational efficiency in breast‑screening-oriented EIT, thereby providing a feasible solution for the application of EIT in breast functional imaging. MethodsThe proposed network adopts a strategy of “locate first, reconstruct later”. It realizes adaptive allocation of computational resources through a dynamic mask module, alleviates information loss in the low-to-high dimensional mapping process via a multi-scale attention mechanism, and embeds physical constraints to improve the physical rationality of reconstruction results. The performance of the proposed method was validated through systematic numerical simulations, agar phantom experiments, and porcine tissue experiments. Comparisons were made with mainstream methods including the Gauss-Newton algorithm, convolutional neural networks, U-Net, and Deep D-Bar. The image correlation coefficient (ICC), root mean square error (RMSE), and peak signal-to-noise ratio (PSNR) were adopted as quantitative evaluation metrics. Furthermore, lesion‑level evaluation metrics were introduced to assess the capability of different methods in reconstructing abnormal target boundaries and small‑sized target regions. ResultsExperimental results demonstrate that MADS-Net outperforms all comparison methods across all test scenarios. In numerical simulations, it achieves higher accuracy in target morphology and spatial location recovery as well as better background suppression. In agar phantom experiments, its detection and imaging reliability for small targets is significantly superior to the comparison methods. In porcine tissue experiments, the model maintains good generalization performance and can adapt to complex biological tissue imaging scenarios. Quantitative results show that MADS-Net achieves an average ICC of 0.917 6±0.048 8, an RMSE as low as0.060 6±0.031 6, and a PSNR of (23.893 9±2.685 3) dB. It successfully detects tiny targets as small as 5 mm within a 100 mm diameter sensing field, reduces the total training duration by 23.5% compared with the baseline method, and maintains stable reconstruction performance even under strong noise interference. ConclusionThe results demonstrate that MADS-Net achieves favorable EIT reconstruction performance in numerical simulations, agar phantom experiments, and porcine tissue experiments, even under common practical imaging challenges including low signal-to-noise ratio and blurred tissue boundaries. This study provides a methodological reference for further research on EIT in breast-screening-related scenarios and other medical functional imaging tasks, and also offers a low-cost, radiation-free alternative for breast lesion screening that aligns with the clinical demand for non-invasive diagnostic tools. It should be noted that real clinical breast data have not yet been used for validation in this study, and the clinical applicability of the proposed method requires further investigation. Future work will prioritize collecting multi-center real clinical breast datasets, and further optimize the model’s generalization ability to adapt to individual differences in breast tissue composition to promote its clinical application.

Currently, the drug delivery system (DDS) based on nanomaterials has become a hot interdisciplinary research topic. One of the core issues is drug loading and controlled release, in which the key lever is carriers. Vaterite, as an inorganic porous nano-material, is one metastable structure of calcium carbonate, full of micro or nano porous. Recently, vaterite has attracted more and more attention, due to its significant advantages, such as rich resources, easy preparations, low cost, simple loading procedures, good biocompatibility and many other good points. Vaterite, gained from suitable preparation strategies, can not only possess the good drug carrying performance, like high loading capacity and stable loading efficiency, but also improve the drug release ability, showing the better drug delivery effects, such as targeting release, pH sensitive release, photothermal controlled release, magnetic assistant release, optothermal controlled release. At the same time, the vaterite carriers, with good safety itself, can protect proteins, enzymes, or other drugs from degradation or inactivation, help imaging or visualization with loading fluorescent drugs in vitro and in vivo, and play synergistic effects with other therapy approaches, like photodynamic therapy, sonodynamic therapy, and thermochemotherapy. Latterly, some renewed reports in drug loading and controlled release have led to their widespread applications in diverse fields, from cell level to clinical studies. This review introduces the basic characteristics of vaterite and briefly summarizes its research history, followed by synthesis strategies. We subsequently highlight recent developments in drug loading and controlled release, with an emphasis on the advantages, quantity capacity, and comparations. Furthermore, new opportunities for using vaterite in cell level and animal level are detailed. Finally, the possible problems and development trends are discussed.

Apurinic/apyrimidinic endonuclease 1(APE 1)is a multifunctional protein that plays important roles in DNA repair and regulation of gene expression.Because APE 1 is overexpressed in various cancers,it can serve as a cancer biomarker for aiding clinical diagnosis,guiding therapy,and monitoring prognosis.On this basis,a label-free fluorescent probe was designed based on the primer exchange reaction(PER)strategy for highly sensitive detection of APE 1 activity.In the absence of APE 1,the structure of catalytic hairpin(HP)was stable and could not form G-quadruplex.Therefore,the background fluorescence of this sensing system was very low due to the dissociation of thioflavin T(ThT).In the presence of APE 1,the apurinic/apyrimidinic(AP)site of HP was cleaved by APE 1 and a short nucleic acid fragment that acted as a primer to initiate PER was generated.After PER reaction,a large number of G-quadruplex were produced,which could specifically bind with ThT and resulted in significant increase of fluorescence signal.The combination of low background design of HP and PER amplification made this biosensor had high sensitivity with a detection limit(3σ)of 0.0008 U/mL.Furthermore,the primer sequence was directly generated by the cleavage of APE 1 without additional addition,which not only increased the specificity of the reaction,but also simplified the experiment procedure.Moreover,the use of label-free fluorescence signal reduced the cost of the experiment,and realized rapid detection of APE 1.Finally,this sensor was used to detect APE 1 in human serum samples with spiked recoveries of 91%-104%,proving great potential in study of biological enzyme.

Nitrofurantoin(NFT)is a nitrofuran antibiotic commonly used as a veterinary drug to treat bacterial infections in animals.However,due to the low solubility and bioaccumulation properties,NFT is prone to leave excessive residues in animal-derived foods and water systems,posing serious threats to human health and ecosystems.Therefore,there is an urgent need to develop an efficient and rapid detection method for NFT.In this work,nitrogen-doped carbon nanomaterials with unique bowl-like structures(N-CNBs)were synthesized via a hydrothermal-carbonization method.The morphology,surface structure,and specific surface area of N-CNBs were characterized using transmission electron microscopy(TEM),scanning electron microscopy(SEM),and X-ray photoelectron spectroscopy(XPS).The N-CNB modified glassy carbon electrode(N-CNB/GCE)was prepared,and the electrochemical test revealed that the N-CNB/GCE exhibited higher conductivity and larger electrochemical active surface area compared to bare GCE and nitrogen-doped hollow carbon nanosphere-modified electrode(N-HCNS/GCE).Additionally,the N-CNB/GCE demonstrated superior electrocatalytic activity toward NFT.An NFT electrochemical sensor was constructed based on N-CNB/GCE.The detection conditions of the sensor were optimized,and differential pulse voltammetry(DPV)was employed for NFT detection under optimal experimental conditions.The established NFT electrochemical sensor had a wide linear range of 0.4-500 μmol/L,a low detection limit(S/N=3)of 0.015 μmol/L and high selectivity,with excellent stability and reproducibility.The practical feasibility of this sensor was confirmed by analysis of NFT in milk and tap water samples,with spiked recoveries ranging from 94.2%to 108.9%.

Objective:To dry fresh Ginseng Radix et Rhizoma using different drying conditions; To investigate the effects of different drying conditions on the drying characteristics and medicinal quality of Ginseng Radix et Rhizoma.Methods:With moisture, powder color, extract, total polysaccharide and ginsenoside contents of Rg 1, Re, Rf, Rb 1, Rc, Rb 2 and Rd as indexes, the drying characteristics of Ginseng Radix et Rhizoma were studied based on Weibull function model, and the quality of Ginseng Radix et Rhizoma after drying was evaluated by entropy weight-TOPSIS model. Results:The drying method for Ginseng Radix et Rhizoma from its origin can be achieved by controlling the relative humidity of the drying medium to 50%, drying at 70 ℃ for 24 h, and then reducing the drying temperature to 60 ℃ until the moisture content was below 12.0%. This method could achieve high drying efficiency and produce high-quality Ginseng Radix et Rhizoma.Conclusions:The drying process of Ginseng Radix et Rhizoma is a falling rate process controlled by internal moisture diffusion. The drying rate of fresh Ginseng Radix et Rhizoma is affected by temperature and humidity. There is a certain correlation between the color of powder and the content of moisture, alcohol-soluble extractives and ginsenosides.

Objective To study the damage effect of high-voltage electric shock on skin based on metabolomics,analyze its metabolic differences,and explore its injury mechanism.Methods A total of 16 SPF C57BL/6J male mice were divided into the electric shock group(head skin received electric shock treatment)and control group(head skin received electric shock acoustic-optical stimulation),and the skin appearance after treatment of mice in the two groups was observed.The histopathological changes caused by electric shock were analyzed by HE staining,EVG staining and Masson staining.GC-MS and LC-MS metabonomics were used to analyze the changes of skin metabolism spectrum and tissue metabolites after electric shock exposure,and the differential metabolites were analyzed.The obtained differential metabolites were combined and KEGG enrichment analysis was conducted.Results After high-voltage electric shock,the skin of mice could be damaged to the dermis,and the epidermis was partially thickened,lifted and separated.The structure of skin appendages in the dermis was destroyed,with a large number of inflammatory cells infiltrating and obvious swelling,accompanied by congestion,which led to severe skin inflammatory reaction and impaired skin barrier function.Metabonomics analysis suggested that the metabolites changed after electric shock exposure.KEGG enrichment analysis showed that electric shock significantly affected the central carbon metabolism pathway of cancer,pentose phosphate pathway,purine metabolism,glycine,serine and threonine metabolism processes,amino acid tRNA biosynthesis mechanism,glycerophospholipid metabolism pathway,pyrimidine metabolism pattern,glycolysis/gluconeogenesis,alanine metabolism process,glucagon signal pathway and so on.Conclusion High voltage electric shock can cause deep skin damage,disturb its energy metabolism and amino acid metabolism,and seriously interfere with its antioxidant and DNA repair system functions.

AIM:This study aims to investigate the molecular mechanism by which tubeimoside I(TBMS1)inhibits Snail expression in pancreatic cancer cells(PANC-1).METHODS:Human pancreatic cancer PANC-1 cells were cultured in vitro.The inhibitory effect of TBMS1 on PANC-1 cells was assessed using the MTT assay,and the data were analyzed based on the IC50 value of TBMS1.The impact of TBMS1 on the clonal formation ability of PANC-1 cells was evaluated through colony formation assays.The Transwell assay was employed to assess the effect of TBMS1 on the migrato-ry capability of PANC-1 cells.Apoptosis and cell cycle alterations in PANC-1 cells were analyzed using acridine orange staining and flow cytometry.The expression of Snail protein in pancreatic cancer and its relationship with survival of the patients were analyzed using the GEPIA database and Kaplan-Meier Plotter data.Immunofluorescence staining was con-ducted to investigate the effect of TBMS1 on Snail expression,while Western blot was used to evaluate the expression of poly(ADP-ribose)polymerase(PARP),E-cadherin and Snail in the cells.The ubiquitination of Snail protein was mea-sured using immunoprecipitation techniques.RESULTS:As the concentration of TBMS1 increased,the survival rate and number of clones formed by PANC-1 cells progressively decreased,leading to apoptosis,cleavage of PARP,and cell cycle arrest in the G1 phase.There was also a reduction in the proportion of cells in the S phase and a decrease in cell migration ability.The expression of Snail protein,a critical factor in cell migration,was inhibited,while E-cadherin protein levels were increased.Treatment with the proteasome inhibitor MG132 was able to reverse the suppression of Snail protein ex-pression caused by TBMS1.Immunoprecipitation results indicated that TBMS1 enhances the ubiquitination and subse-quent degradation of Snail protein.CONCLUSION:TBMS1 effectively inhibits the malignant progression of pancreatic cancer cells by promoting the ubiquitination and degradation of Snail protein in PANC-1 cells.