3CL protease (3CLpro) of SARS-CoV-2 is a pivotal enzyme required in coronavirus replication and transcription. Its highly conserved structure and the absence of homologous proteins in the host make it an ideal target for broad-spectrum anti-coronavirus drug development. In this work, we systematically investigated and compared the binding modes and dynamic properties of the four stereoisomers of a pyridyl-urea diyne ester (PyDU) molecule with two chiral centers within the 3CLpro active site. Through molecular docking, MD simulations, MM/GBSA binding free-energy calculations, and DCCM analysis, all four stereoisomers were stabilized primarily by hydrophobic packing. Among them, the (R,S) isomer exhibited the best overall performance, including docking score, binding free-energy components, and key residue interactions. The (R,S) and (S,R) isomers also enhanced the cooperative motions around the binding pocket, while the (R,S) isomer further modulated the flexibility of domain III, which may influence 3CLpro dimerization. Conversely, the (S,S) isomer exhibited the weakest affinity due to insufficient hydrophobic contact. By innovatively integrating chirality, binding energy and protein dynamical features, we revealed the dual role of chirality in modulating affinity and dynamic responses, which provides a theoretical basis for the chiral-guided design of coronavirus inhibitors.

ObjectiveTo investigate the effects of salidroside （SAL） on the impaired bioactivity of endothelial progenitor cells （EPCs） in atherosclerotic （As） mice and the potential mechanisms regarding AMP-activated protein kinase （AMPK）. MethodsAtherosclerosis was induced in 8-week-old male ApoE^-/- mice with high-fat diet. Intragastric administration of SAL was given to one mice group to investigate the effects of SAL on aortic plaque burden， plasma NO level， the migration and angiogenic capabilities of bone marrow-derived EPCs （BM-EPCs）. The proliferation， migration and vasculogenic properties of EPCs isolated from As mice were investigated in vitro. AMPK-sh-RNA or the AMPK inhibitor Compound C was used to investigate the role of AMPK/Akt/eNOS pathway in the regulatory effects of SAL. ResultsCompared with As group， NO level was significantly elevated in SAL group. The sizes of atherosclerotic plaques at the aortic root were reduced with smaller lipid cores in SAL group compared with As group. Moreover， the migration and angiogenesis capacity of EPCs markedly decreased in As mice， while SAL treatment reversed these impairments. Incubation with SAL at concentrations of 20， 40， and 80 μmol/L for 48 hours significantly promoted the proliferation， migration， and angiogenesis of EPCs. AMPK-sh-RNA transfection abrogated the 20 μmol/L SAL improvement in EPC biological activities. Western blot analysis further demonstrated that treatment with Compound C blocked the activation of AMPK/Akt/eNOS signaling pathway induced by SAL. ConclusionSAL upregulates the biological functions of EPCs through activating the AMPK/Akt/eNOS signaling pathway， thereby ameliorating EPC dysfunction during the pathological progression of atherosclerosis.

ObjectiveTo evaluate the detection specificity for clinical samples and the detection capability for standard substances of five commercially available multiplex polymerase chain reaction (PCR) nucleic acid detection kits (hereinafter referred to as the kits) for respiratory pathogens, and to provide a reference for selecting appropriate detection kits for multi-pathogen nucleic acid testing of respiratory infections. MethodsA total of 60 respiratory pathogen-positive clinical samples with known redults were selected and tested using the five kits (labeled as A, B, C, D, and E). The detection rates and Kappa coefficients were calculated to evaluate the consistency between the results from these kits and those from single-pathogen PCR kits. According to the limit of detection (LOD) provided by the kits, standard substances of respiratory pathogens (including 12 types such as influenza virus, Mycoplasma pneumoniae, and Bordetella pertussis) were diluted to four concentrations (250, 500, 1 000, and 2 000 copies·mL⁻¹). All five kits were used for detection to evaluate their respective detection capabilities. ResultsCompared with the results from single-pathogen PCR kits, the five tested kits demonstrated good consistency (all Kappa >0.80). Among them, Kit A had the highest detection rate (100.00%), followed by Kits C and E (98.33%), and then Kits B and D (95.00%). All five kits showed a relatively low false negative rate (FNR) for samples with a cycle threshold (Ct) value ≤35 (≤2.38%). However, for samples with Ct values>35, the FNR increased accordingly(average FNR=6.67%, P=0.029). Kit C exhibited the highest detection sensitivity for the tested standard substances (average LOD: 458.33 copies·mL⁻¹), followed by Kit D, then Kits A/E, and finally Kit B. ConclusionThe five multiplex PCR kits showed good consistency with single-pathogen detection results, but each had its own performance emphasis. Kit A, with the highest detection rate and high throughput, is suitable for targeted viral screening. Kit B, covering the broadest pathogen spectrum (including fungi/bacteria), is suitable for comprehensive respiratory pathogen screening. Kits C, D and E, are applicable for rapid detection. It is important to note that the detection efficacy of all kits decreases for low viral load samples with Ct values >35. In practical application, selection should be based on specific screening objectives, throughput requirements, and sample types.

Objective To gain insights into the biological characteristics of different populations of Culex tritaeniorhynchus within and around the Yellow Sea wetland from the perspective of the occurrence of resistance, we investigated the levels of resistance to deltamethrin and kdr gene mutation in the wetland and its peripheral areas. Methods Specimens were collected from Cx. tritaeniorhynchus populations at two monitoring sites in the Rare Bird National Nature Reserve and Tiaozi Ni Wetland Scenic Area, and also from two populations in Yancheng City and the Liuhe District of Nanjing, and the resistance of these mosquitoes to deltamethrin was determined using the CDC biotest bottle method. For each concentration of deltamethrin assessed, a random subset of exposed specimens was selected for amplification of the kdr gene fragment, followed by Sanger sequencing to identify and analyze resistance-associated mutations. Results The LC50 levels of deltamethrin among mosquitoes from the four populations in Luhe, Yancheng, the Rare Bird National Nature Reserve and the Tiaozi Ni Wetland Scenic Area were 2.048 5, 7.798 2, 3.473 3, and 17.695 5 mg/mL, respectively, with corresponding concentrations of deltamethrin ranging from 0.005 to 5.000,0.050 to 50.000,0.050 to 25.000 and 0.050 to 50.000 mg/mL, respectively. Furthermore, the ranges of the KT50 values were 11.76-107.43, 67.05-216.30,29.77-107.43 and 28.40-329.51 min; the 1-h knockdown rates were 34.58%-99.15%, 9.52%-43.80%, 55.09%-73.01%, and 10.09%-68.07%; and the 24-h mortality rates were 12.15%-67.52%,9.52%-79.56%,13.17%-82.21%, and 11.01%-78.99%, respectively. With respect to kdr gene mutation, we assayed a total of 63,70,59, and 57 mosquitoes for the four populations, for which we detected L1014F mutation frequencies of 14.29%, 35.00%, 20.34%, and 31.58%, respectively, with a majority of these mutations being heterozygous for resistance. In addition, five adult mosquitoes were identified has having synonymous mutations at site 1011[i. e. , AAT(asparagine)mutation to AAC(asparagine)]. Conclusions Our findings revealed the clear resistance of Cx. tritaeniorhynchus to deltamethrin in the Yancheng region of the Yellow Sea wetland, and the resistance phenotype and kdr frequency of Cx. tritaeniorhynchus in the wetland environment were comparable to those of Cx. tritaeniorhynchus in the wetland environment, thereby indicating that the resistance of different populations of Cx. tritaeniorhynchus was homogeneous under the pressure of different insecticide selection within and around the wetland. However, the underlying mechanisms need to be further studied.

Objective: To systematically analyze the stability and decay kinetics of coagulation factors in thawed cryoprecipitate stored at different temperatures under the new storage guidelines, and to provide an evidence basis for optimizing storage strategies. Methods: A total of 30 bags of 2U cryoprecipitate prepared at our blood center from January to June 2025 were selected. After thawing in a 37℃ water bath and thorough mixing, each bag was equally divided into two portions and stored at room temperature (20-24℃) or under refrigerated temperature (2~6℃), respectively. Dynamic sampling was performed at 0, 4, 6, 24, 30, and 120 h after thawing to measure fibrinogen (FIB) content, coagulation factor Ⅷ(FⅧ) activity, and von Willebrand factor (vWF) activity. Two-way repeated measures ANOVA was used to evaluate the effects of storage temperature, time, and their interaction. A one-phase exponential decay model was applied to fit the decay kinetics of FⅧ activity and vWF activity. Results: After thawing, FⅧ activity and vWF activity in cryoprecipitate showed a decreasing trend with prolonged storage time, and a time×temperature interaction was observed for both factors (all P< 0.001). The decay rates of FⅧ activity and vWF activity were lower under room temperature storage than under refrigerated storage, with statistically significant differences between the two groups starting from 24 h. Kinetic fitting revealed that the half-life of FⅧ activity in the room temperature group (19.83 h) was 3.4 times longer than that in the refrigerated group (5.85 h); the half-life of vWF activity in the room temperature group (204.6 h) was 5.9 times longer than that in the refrigerated group (34.6 h). FIB content remained stable throughout the observation period under both storage temperatures, with no statistically significant differences. Conclusion: Storage of thawed cryoprecipitate at room temperature effectively delays the loss of FⅧ activity and vWF activity and reduces cryoprecipitate formation induced by low temperature, providing experimental evidence for optimizing transfusion strategies based on the decay kinetics of different coagulation factors and improving the utilization efficiency of cryoprecipitate resources.

Objective To establish the method of thin layer chromatography （TLC） for identification and content quantitative determination of Shugantongluo capsules, and provide methodological reference for the quality control of Shugantongluo capsules. Methods Bupleuriradix, polygala tenuifolia yuanzhi, and acorus tatarinowii rhizoma were identified by TLC qualitatively. The content of Saikosaponin-a was determined by HPLC method. The chromatography was performed on Venusil XBP C₁₈（L） （4.6 mm×150 mm, 5 μm） with a stable temperature of 30℃. The mobile phase in isocratic elution consisted of acetonitrile-water （40∶60, V/V） at the flow rate of 1.0 ml/min with an injection volume of 20 μl. The detection wavelength was set at 210 nm. Results Clear spots were obtained with good separation in TLC identification which was highly specific. The Saikosaponin-a at the range of 25.00-500.0 μg/ml was linear with peak area （r=0.999 9）, the average recovery rate was 97.00%, and RSD was 2.60%. Conclusion These methods was easy to operate with accurate results, with good specificity and reproducibility, which could be uesd for the quality control for Shugantongluo capsules.

ObjectiveTo develop and preliminarily validate a prediction model for brace treatment failure risk in patients with adolescent idiopathic scoliosis (AIS), based on information obtained before brace treatment and during initial brace fitting. MethodsA total of 191 patients with AIS who initiated thoracolumbosacral orthosis treatment at Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese Medicine from March, 2015 to August, 2024 and had determinable outcomes were retrospectively included. Patients were divided according to a prespecified scheme into a training set (n = 133) and a validation set (n = 58). Brace treatment failure was defined as progression of the major-curve Cobb angle by ≥ 5° from baseline during follow-up or at brace weaning, or a final major-curve Cobb angle > 45°. Logistic regression, random forest, support vector machine with radial basis function kernel, and extreme gradient boosting (XGBoost) models were developed using routinely available clinical and radiographic variables before brace treatment and during initial brace fitting. Stratified five-fold cross-validation was used for hyperparameter tuning in the training set. Model performance was evaluated in the validation set using the area under the receiver operating characteristic curve (AUC), area under the precision-recall curve (AUPRC), Brier score, calibration curves, and decision curve analysis (DCA). SHapley Additive exPlanations (SHAP) was used to interpret the main explanatory model. ResultsIn cross-validation of the training set, both random forest and XGBoost showed good discriminative performance, with cross-validation-AUC values of 0.871 and 0.880, respectively. In the validation set, the AUC values of random forest and XGBoost were 0.888 and 0.899, the AUPRC values were 0.678 and 0.830, and the Brier scores were 0.086 and 0.076, respectively. Random forest was selected as the primary model for interpretation, with a calibration intercept of 0.091 and a calibration slope of 0.995. SHAP analysis indicated that the in-brace correction rate and the major-curve Cobb angle measured in the brace contributed most to the model predictions. ConclusionThe random forest model developed using routinely available pretreatment and initial-fitting variables shows preliminary predictive value for brace treatment failure risk in AIS, and may provide quantitative support for follow-up scheduling, brace-fit reassessment and early adherence-oriented management.

Background and aims The mechanism of cholestatic liver injury (CLI) is unclear, and effective therapies are lacking. While peroxisome proliferator-activated receptor alpha (PPARα) agonists show potential hepatoprotective effect and pyroptosis is implicated in hepatocellular damage, how PPARα activation mitigates lithocholic acid (LCA)-induced pyroptosis remains unknown. Methods The hepatoprotective effect of PPARα agonists was evaluated in a mouse model of intrahepatic cholestasis induced by LCA. Liver injury was assessed via serum biochemistry, hematoxylin and eosin and TUNEL staining, and electron microscopy. Pyroptosis pathways were analyzed using real-time quantitative polymerase chain reaction, Western blot, and co-immunoprecipitation. Results Combined morphological, histopathological, and biochemical analyses confirmed that PPARα activation protects against CLI. Compared with LCA treatment alone, PPARα activation significantly attenuated the elevation of serum lactate dehydrogenase (LDH), the increased TUNEL-positive cells, and the formation of hepatocyte membrane pores. Mechanistically, PPARα activation suppressed both NOD-like receptor protein 3 (NLRP3) inflammasome-mediated pyroptosis and apoptosis protease-activating factor-1 (APAF-1)/CASPASE-3/GSDME-mediated pyroptosis. Furthermore, PPARα agonist pretreatment inhibited activation of the nuclear factor-kappa B (NF-κB) and forkhead box O1 (FOXO1) signaling pathways. Conclusions PPARα protects against LCA-induced CLI by inhibiting both NLRP3 inflammasome-mediated pyroptosis associated with NF-κB and APAF-1/CASPASE-3/GSDME-mediated pyroptosis associated with the FOXO1 signaling pathway.

With the rapid development of generative artificial intelligence(GAI)technologies,their widespread application in academic research and writing is continuously expanding the boundaries of sci-entific inquiry.However,this trend has also raised a series of ethical and regulatory challenges,inclu-ding issues related to authorship,content authenticity,citation accuracy,and accountability.In light of the growing involvement of AI in generating academic content,establishing an open,controllable,and trustworthy ethical governance framework has become a key task for safeguarding research integrity and maintaining trust within the academic community.This expert consensus outlines ethical requirements across key stages of AI-assisted academic writing-including topic selection,data management,citation practices,and authorship attribution.It aims to clarify the boundaries and ethical obligations surrounding AI use in academic writing,ensuring that technological tools enhance efficiency without compromising in-tegrity.The goal is to provide guidance and institutional support for building a responsible and sustainable research ecosystem.

AIM:To investigate the possible mechanism how orphan nuclear receptor 4A1(NR4A1)affects renal fibrosis in unilateral ureteral obstruction(UUO)mice.METHODS:(1)Specific pathogen-free(SPF)male C57BL/6J mice(5 to 6 weeks old)were randomly divided into sh-Con+sham group(n=6),sham+sh-NR4A1 group(n=6),sh-NR4A1+UUO group(n=6),and sh-NR4A1+UUO group(n=6).Renal NR4A1 knockdown mice were prepared by intrarenal injection of NR4A1 viral vector.(2)SPF male C57BL/6J mice(5 to 6 weeks old)were randomly assigned to in sham group,UUO group,and UUO+cytosporone-B(Csn-B)group.An animal model of renal fibrosis was prepared by UUO,and Csn-B was intervened for 14 days.HE,Masson,and Sirius red staining were used to observe renal pathological damage.Immunohistochemistry and Western blot were performed to detect the expression of NR4A1,interferon-γ(IFN-γ),α-smooth muscle actin(α-SMA)and vimentin.The purpose of this study is to observe the regulatory effect of NR4A1 on UUO-induced renal fibrosis.RESULTS:(1)The expression of NR4A1 was decreased in kidney tissues of UUO mice(P<0.05).(2)HE staining results showed that there are tubular dilation,atrophy,and massive inflammatory cell infiltra-tion in sh-Con+UUO group,and NR4A1 knockdown can aggravate UUO-induced kidney damage(P<0.05).The results of Masson and Sirius red staining showed a banded distribution of collagen deposition in the sh-Con+UUO group,and colla-gen deposition increased significantly after NR4A1 knockdown(P<0.05).Treatment with Csn-B could improve renal path-ological damage and reduce collagen deposition.(3)UUO could upregulate the expression of α-SMA and vimentin,and NR4A1 knockdown could significantly increase UUO-induced their expression(P<0.05).In addition,Csn-B could im-prove UUO-induced renal fibrosis(P<0.05).(4)The expression of IFN-γ was increased in UUO mice,and NR4A1 knockdown could upregulate UUO-induced IFN-γ expression(P<0.05).Moreover,Csn-B could down-regulate UUO-in-duced IFN-γ expression(P<0.05).CONCLUSION:NR4A1 can affect renal fibrosis by regulating IFN-γ in UUO mice.