AIM: To investigate the protective effect of β-sitosterol on retinal structure and function and its underlying molecular mechanism in a sodium iodate(NaIO3)-induced mouse model of dry age-related macular degeneration(ARMD).METHODS: A dry ARMD mouse model was established by NaIO3 injection. The therapeutic effect of β-sitosterol intervention was evaluated using fundus photography, histopathology(HE staining), and electroretinography(ERG). Network pharmacology was employed to screen potential targets of β-sitosterol in ARMD, and molecular docking was used to validate the binding ability between β-sitosterol and these targets. The impact of β-sitosterol on ARPE-19 cell viability and apoptosis pathways was analyzed using CCK-8 assay, Hoechst staining, and Western blotting.RESULTS: The β-sitosterol significantly alleviated structural damage in the retinas of model mice(increased retinal and outer nuclear layer thickness, reduced yellowish-white drusen-like deposits)and functional impairment(partial restoration of a-wave and b-wave amplitudes). Network pharmacology identified PON1 as a key target of β-sitosterol; molecular docking demonstrated that β-sitosterol binds to PON1 via hydrophobic interactions and hydrogen bonds. In vitro experiments showed that β-sitosterol(10 μmol/L)significantly increased ARPE-19 cell viability(P<0.01), reduced apoptosis(P<0.01), upregulated PON1 expression(P<0.01), and concurrently suppressed cleaved-Caspase3 expression(P<0.01).CONCLUSION: The β-sitosterol likely protects against oxidative stress-induced retinal damage by modulating PON1 to suppress the Caspase3-dependent apoptotic pathway. These findings provide experimental evidence supporting the development of β-sitosterol as a novel therapeutic agent for dry ARMD.

AIM: To investigate the relationship between vascular smooth muscle cell (VSMC) injury, organelle stress response and autophagic cell death (autophagy) and ferroptosis induced by the chemical hypoxia inducer cobalt chloride (CoCl2) through the bioinformatics analysis and in vitro cell experimentation. METHODS: The dataset GSE119226 of VSMC treated with cobalt chloride was acquired from the gene expression database (GEO). The R language was used to investigate the relationship between CoCl2 treatment and organelle stress response (Golgi stress, endoplasmic reticulum stress) and two forms of cell death (ferroptosis and autophagic cell death). With primary cultured rat VSMC (rVSMC) and CoCl2-induced anoxia model, the changes in cell viability were detected by CCK-8 method, and reactive oxygen species (ROS) levels were measured using DCFH-DA method. The expression levels of HIF-1α (a key molecule in hypoxia), Golgi stress markers GM130 and p115, endoplasmic reticulum stress markers GRP78 and CHOP, autophagy markers LC3-II / LC3-I and Beclin1, and ferroptosis markers GPx4 and xCT were detected by Western blot. The effect of inducing or inhibiting organelle stress and cell death on the CoCl2-induced cell damage was also observed. RESULTS: Differentially expressed genes analysis of GSE119226 dataset showed that CoCl2 treatment of VSMCs had significant effects on organelle function and stress response, autophagy and ferroptosis-related genes, in which endoplasmic reticulum stress, protein processing in endoplasmic reticulum, regulation of Golgi to plasma membrane protein transport, autophagy / autophagic cell death, and ferroptosis pathways were remarkably enriched. The results of in vitro experiment showed that compared with normal rVSMC, cell viability was significantly decreased after CoCl2 treatment, as well as HIF-1α protein expression and ROS levels in rVSMCs were increased. In rVSMC treated with Co-Cl2, the expression levels of Golgi structural proteins GM130 and p115 (reflecting the occurrence of Golgi stress) were decreased, while the markers GRP78 and CHOP (reflecting the occurrence of endoplasmic reticulum stress) were increased. At the same time, CoCl2 treatment also reduced the expression of autophagy markers LC3-II/LC3-I and Beclin1 (indicating the decrease levels of autophagy), while the expression of ferroptosis markers GPx4 and xCT were decreased (indicating the occurrence of ferroptosis). Compared with CoCl2 treatment group, induced Golgi stress, endoplasmic reticulum stress, or ferroptosis could further reduce cell viability, while inhibition of these processes could improve cell viability. On the other hand, increasing the level of autophagy can improve the cell viability. CONCLUSION: Hypoxia induced by cobalt chloride can lead to VSMC injury. Golgi stress, endoplasmic reticulum stress, ferroptosis, and the reduction of autophagy level play an important role in it. Inhibition of organelle stress response and ferroptosis, or increase of autophagy level can improve VSMC injury caused by cobalt chloride.

Abstract: The differential expression and subcellular localization of single-cell proteins are closely related to the physiological state and pathological mechanisms of the body. The development of single-cell protein in situ imaging methods provides powerful tools for spatial single-cell proteomics research and single-cell protein profiling. This article summarizes the single-cell protein imaging methods developed in recent years, including the circulating immunofluorescence imaging methods based on ordered multi-round antibody incubation, mass spectrometry imaging based on metal element labeled antibodies, fluorescence imaging based on DNA-barcoded antibody, gene encoded fluorescence protein imaging and spectral imaging based on Raman spectroscopy or X-ray spectroscopy, with brief explanation of the imaging principles of these methods. It focuses on the multiple performance, imaging resolution and signal amplification performance of these methods, and analyzes their application characteristics in practical scientific research and clinical work, in the hope of providing some reference for the development of more revolutionary single-cell imaging methods, and promoting the development of biomedical and precision medicine.

Objective:To analyze the clinical characteristics, imaging, myopathology and outcomes of patients with COVID-19 related autoimmune myopathy.Methods:The clinical features, serum creatine kinase (CK), myositis antibodies, muscle magnetic resonance imaging, myopathology and therapy of 5 patients with COVID-19 related autoimmune myopathy diagnosed in Peking University First Hospital from December 2022 to April 2023 were collected. The effects of the therapy after a short term follow up were analyzed.Results:Among the 5 patients, there were 3 males and 2 females, with onset age of 42-86 years. All patients presented with proximal muscle weakness in the recovery term of COVID-19. Myalgia was noted in 3 cases, dysphagia in 1, skin damage in 2, interstitial lung disease in 1. The serum CK of the 5 patients was 1 663-16 000 IU/L, 1 patient had anti-3-hydroxy-3-methylglutaryl-CoA reductase autoantibodies and 1 patient had anti-signal recognition particle autoantibodies. The electromyography showed myogenic lesions in all patients. Muscle magnetic resonance imaging showed diffuse muscle edema in all patients, myofascial edema in 3 and subcutaneous-tissue edema in 3. The muscle biopsies in 4 patients revealed necrotic myopathy,with high P62 expression in muscle fibers. The electromicroscopy of 2 patients revealed vacuolated mitochondria and intranuclear tubulofilamentous inclusions in muscle fibers. Four patients were treated with glucocorticoids, of whom 2 patients combined with intravenous immunoglobulin, tacrolimus or cyclophosphamide. One case had close monitoring without drug therapy. They showed significant improvement, but the CK was still abnormal in 4 patients.Conclusions:COVID-19 leads to immune mediated myopathy. The manifestation of patients is characterized by proximal predominant weakness and high creatine kinase level. Muscle magnetic resonance imaging shows diffuse muscle edema. The muscle biopsies reveal necrotic myopathy. The effectiveness of immunosuppression needs to be further studied.

Objective:To study positive rates and typing of oligoclonal bands (OCB) in patients with neurological disorders, and to reveal the clinical significance and applicational value of OCB test.Methods:A retrospective analysis was performed on the detection results of 3 217 patients with neurological disorders who undertook both serum and cerebrospinal fluid OCBs in the First Hospital of Peking University from January 2012 to August 2022. According to the final diagnosis, the patients were divided into 13 groups including multiple sclerosis (479 cases), neuromyelitis optica spectrum disorders (935 cases), autoimmune encephalitis (192 cases), viral encephalitis (94 cases), nervous system complication after HSCT (232 cases), Guillain-Barré syndrome (644 cases), chronic inflammatory demyelinating polyneuropathy (157 cases), etc. Cerebrospinal fluid and serum OCBs were detected using isoelectric focusing electrophoresis combining immunofixation, then classified into Ⅰ-Ⅴ types according to the morphology. Consequently, positive rates and types were analyzed for each group. χ2 test was used for comparison between groups. Results:The positive rates of cerebrospinal fluid OCB in multiple sclerosis, nervous system complication after hematopoietic stem cell transplantation (HSCT), autoimmune encephalitis, viral encephalitis, neuromyelitis optica spectrum disorders, Guillain-Barré syndrome and chronic inflammatory demyelinating polyneuropathy were respectively 66.8% (320/479), 48.7% (113/232), 46.4%(89/192), 19.1% (18/94), 17.6% (165/935), 9.9% (64/644), 5.1% (8/157). For patients with multiple sclerosis, neuromyelitis optica spectrum disorders, viral encephalitis, and autoimmune encephalitis, Type Ⅱ bands took the majority of cerebrospinal fluid OCB-positive cases with the rates of 94.1% (301/320), 78.7% (70/89), 77.8% (14/18), and 77.6% (128/165) respectively, indicating intrathecal IgG synthesis; for patients with nervous system complication after HSCT, Guillain-Barré syndrome and chronic inflammatory demyelinating polyneuropathy, type Ⅳ bands took the majority of cerebrospinal fluid OCB-positive cases with the rates of 94.7% (107/113), 82.8% (53/64) and 100% (8/8), indicating no obvious intrathecal IgG synthesis. The positive rates of cerebrospinal fluid oligoclonal bands were significantly different among all groups (χ 2=1 268.31, P<0.001). Conclusion:The positive rates of cerebrospinal fluid oligoclonal bands are different among different neurological disorders, in which the positive rate of cerebrospinal fluid OCB is higher with type Ⅱ bands as the majority type in multiple sclerosis, which indicates that the detection and typing of cerebrospinal fluid OCB are helpful for the diagnosis of various neurological diseases, especially for multiple sclerosis.

Objective The study aims to optimize the conditions for constructing orthotopic nude mouse models of liver cancer by injecting human liver tumor cell lines and to explore appropriate timings for drug administration. Methods Human hepatocellular carcinoma Hep3B and hepatoblastoma HepG2 cell lines, which stably expressing the luciferase reporter gene (LUC), were selected. The linear correlation between the luciferase luminescence intensity and the number of liver tumor cells was analyzed using a Small Animal In Vivo Imaging system to verify the luminescent efficiency of the human liver tumor cells. Different concentrations (8×10⁶, 2.4×10⁷, 7.2×10⁷ cells/mL) and resuspension media (PBS, Matrigel) of human liver tumor cell suspensions HepG2-LUC and Hep3B-LUC were orthotopically inoculated into the liver lobes of 5-week-old female BALB/c nude mice (12 groups, 7 mice each) to construct human liver tumor nude mouse orthotopic cancer models. Every 7 days, the weights of mice were recorded, and the growth of orthotopic tumors was monitored using the Small Animal In Vivo Imaging system. On day 35 post-cell inoculation, mouse livers were dissected, and pathological slices were prepared for HE staining to observe histopathological changes in liver tissues. Results The luminescence intensity of human liver tumor cell lines was positively correlated with the number of cells (R²=0.983 1, R²=0.970 5), indicating their suitability for orthotopic model construction. Successful modeling was achieved in the high-concentration groups of HepG2-LUC, the low-, medium-, and high-concentration groups of HepG2-LUC+Matrigel, the medium- and high-concentration groups of Hep3B-LUC, and the low-, medium-, and high-concentration groups of Hep3B-LUC+Matrigel. For both HepG2-LUC+Matrigel and Hep3B-LUC+Matrigel groups, mice in the high-concentration groups exhibited significantly reduced body weight compared to the low- and medium-concentration groups (both with P<0.05). The luminescence intensity of successfully modeled mice increased exponentially over time (R²>0.950 0), and reached a minimum of 1.0×10⁷ p/(s·cm²·sr) by day 14 post-transplantation. Mice in the low- and medium-concentration groups of HepG2-LUC and the low-concentration group of Hep3B-LUC showed no significant pathological changes, while the other groups exhibited evident liver tumors and hepatocyte lesions. Conclusion For the HepG2-LUC cell line, the recommended injection volume is 50 µL with a cell density of 2.4×10⁷ cells/mL, resuspended with Matrigel, followed by drug administration or prognostic measures on day 7 post-modeling. For the Hep3B-LUC cell line, the recommended injection volume is 50 µL with a cell density of 7.2×10⁷ cells/mL, not resuspended with Matrigel, with administration or prognostic measures on day 14 post-modeling.

Fungal infections of the digestive tract in children can be caused by a variety of fungi, the most common of which are Candida and Aspergillus.Occurrence of invasive fungal infections is dependent on numerous factors including geographic location and routes of exposure, and host factors, such as predisposing conditions, high-risk medications, or underlying medical comorbidities that modulate overall immune function.However, advances in DNA and ribosomal RNA sequencing and serologic testing have led to shifts in how gut fungal microbiota are identified and in diagnosing opportunistic infections.This article will briefly expound the common pathogens, risk factors, clinical manifestations, diagnosis, and treatment of gastrointestinal fungal infections in children.

Objective To investigate the multi spiral computed tomography(MSCT)characteristics of intraductal papillary neo-plasm of the bile duct(IPNB)and to distinguish the benign and malignant ones.Methods The MSCT and clinical data of 23 patients with IPNB confirmed by pathology were analyzed retrospectively.According to the pathology,they were divided into benign and malignant groups,including 12 cases of benign group(7 cases with low to medium grade intraepithelial neoplasia,and other 5 cases with high grade intraepithelial neoplasia)and 11 cases of malignant group with invasive carcinoma.All patients underwent plain and tri-phasic enhanced CT scans of upper abdomen.The enhanced scan included arterial phase,portal phase and delayed phase.The location,size,growth mode,enhancement type,invasion and metastasis,bile duct manifestations and bile duct stones were analyzed.Independent sample t-test was used to count the transverse diameter,longitudinal diameter and aspect ratio of tumor.Chi square test was used to compare the difference in other parameters between benign and malignant groups.Results There were no significant differences between benign and malignant IPNB groups in the location of the disease,the transverse diameter of the tumor,the dilatation of the bile duct and the presence of the stones(P>0.05).However,the significant differences in tumor growth mode,tumor longitudinal diameter and aspect ratio,enhancement type,invasion of bile duct wall and bile duct truncation were found(P<0.05).Conclusion Benign IPNB is common,while the IPNB with diffuse growth,progressive enhancement,invasion of bile duct wall and extrabiliary structures,and distant metastasis may indicate malignance,and the final diagnosis depends on the pathology.

ObjectiveTo investigate the role and mechanism of hyodeoxycholic acid （HDCA） in the progression of metabolic associated fatty liver disease （MAFLD）， and to provide a new theoretical basis for further clarifying the pathogenesis of MAFLD. MethodsL02 hepatocytes were used as experimental cells， and palmitic acid was used to induce steatosis in L02 cells. The farnesoid X receptor （FXR） siRNA interference chain technique was used to construct a hepatocyte cell line with low FXR expression. CCK8 assay was used to observe the effect of HDCA on L02 steatosis hepatocytes at different concentrations （0， 100， 200， 300， and 400 μmol/L） and time points （12， 24， 36， and 48 hours）. The method of qRT-PCR was used to measure the mRNA expression levels of FXR， proliferating cell nuclear antigen （PCNA）， Cyclin D1， phosphatidylinositol 3-kinase （PI3K）， and protein kinase-B （AKT）， and Western blot was used to measure the protein expression levels of FXR， Cyclin D1， PCNA， PI3K， phosphorylated PI3K （p-PI3K）， AKT， and phosphorylated （p-AKT）. A one-way analysis of variance was used for comparison of normally distributed continuous data with homogeneity of variance between multiple groups， and the Tukey HSD test was used for further comparison between two groups； the Welch analysis of variance was used for comparison of normally distributed continuous data with heterogeneity of variance between multiple groups， and the Games-Howell test was used for further comparison between two groups. The independent-samples t test was used for comparison between two groups. ResultsCCK8 assay showed a significant reduction in the viability of L02 cells and steatosis hepatocytes treated by 300 μmol/L HDCA （P<0.05）， and qRT-PCR showed a significant increase in the mRNA expression level of FXR and significant reductions in the mRNA expression levels of PCNA， Cyclin D1， PI3K， and AKT （all P<0.05）. Western blot showed a significant increase in the protein expression level of FRX （P<0.05）， and after interference of FXR expression in L02 cells， there were significant increases in the protein expression levels of PCNA， PI3K， p-PI3K， AKT， and p-AKT （all P<0.05）. ConclusionHDCA inhibits the PI3K/AKT signaling pathway by upregulating FXR expression， thereby inducing a reduction in the viability of steatosis hepatocytes.

Objective The study aimed to elucidate the evolution of the syndromes in Traditional Chinese Medicine(TCM)and TCM syndrome elements in different chronic stages of psoriasis vulgaris.Methods A database was constructed using electronic medical records collected from July 2019 to March 2024 from 1,049 patients with psoriasis vulgaris.The study used Sankey diagrams and network association graphs to analyze the evolution of TCM syndromes and their elements in patients at the different stages:initial diagnosis,progressive stage(Week 2-3),progressive stage(Week 4-5),skin lesion improvement stage(Week 6-7),and remission stage.The syndrome elements network was constructed using community detection algorithms,and the association rules between local skin lesion syndrome differentiation and overall syndrome differentiation were displayed using heatmaps.Results(ⅰ)Initial diagnosis.In the syndrome differentiation of local skin lesions,blood heat syndrome was the most common(79.79％);among the disease location of TCM syndrome elements(called"disease location"),liver was the most prevalent(35.62％);and among the pathological factors of TCM syndrome elements(called"pathological factors"),fire(heat)was the most common(75.48％).(ⅱ)Active stage(Week 2-3).In the syndrome differentiation of local skin lesions,blood heat syndrome remained the most prevalent(73.13％);among the disease location,liver was still the most prevalent(31.71％);and among the pathological factors,fire(heat)continued to be the most common(82.11％),while dampness(22.26％)and qi stagnation(8.39％)began to increase.(ⅲ)Active stage(Week 4-5).The syndrome differentiation of local skin lesions was dominated by blood heat syndrome(45.91％)and blood dryness syndrome(37.19％);among disease location,the interior was the most prevalent(15.25％);and among the pathological factors,fire(heat)remained the most common(50.66％),with an increase in yin deficiency(34.26％).(ⅳ)Skin lesion improvement stage(Week 6-7).In the syndrome differentiation of local skin lesions,both blood dryness syndrome(49.44％)and blood stasis syndrome(33.33％)increased;among the disease location,meridians increased most significantly and became the most prevalent(13.44％);and among the pathological factors,blood stasis increased most significantly and became the most prevalent(28.20％).(ⅴ)Remission stage.In the syndrome differentiation of local skin lesions,blood stasis syndrome became the primary(55.69％),while the percentage of blood dryness syndrome decreased(21.16％);meridians(25.71％)and blood stasis(62.34％)remained the most predominant syndrome elements related to disease location or pathological factors.Conclusion The overall pattern of TCM syndromes in psoriasis vulgaris evolved from excess to deficiency.From the initial diagnosis to the active phase(Week 2-3),heat syndrome dominated;during the active phase(Week 4-5),heat syndrome coexisted with damp syndrome or yin deficiency syndrome;changes in the syndrome element network were the most significant during the lesion improvement phase,with blood stasis gradually increasing and peaking during the remission phase.Blood stasis,dampness,and qi stagnation were pervasive throughout psoriasis vulgaris;qi stagnation and blood stasis may be the main elements causing further deterioration and prolonged course of the disease during the active phase in patients.