Objective:A monoclonal cell line that stably expresses transmembrane protease serine 2 (TMPRSS2) was constructed using the PiggyBac (PB) transposon system to establish a technique for isolating human parainfluenza viruses (HPIVs) without rely on exogenous trypsin.Methods:The pB513B/TMPRSS2 recombinant expression plasmid was synthetized based on the principle of PB transposition, and co-transfected into LLC-MK2, HEp-2, and Vero cells, together with the helper plasmid. Positive cells were then identified using the puromycin resistance and limiting dilution method. Stable TMPRSS2 expression was verified by PCR and western blot (WB). Furthermore, the viral replication capacity of the cell lines was evaluated using digital PCR and immunostaining plaque assays.Results:The successful construction of the recombinant plasmid pB513B/TMPRSS2 was confirmed through restriction enzyme digestion and DNA sequencing. Following transfection, the LLC-MK2/TMPRSS2 cell survival rate was higher than those of the HEp-2/TMPRSS2 and Vero/TMPRSS2 cells. Subsequent PCR and WB analysis results revealed that the LLC-MK2/TMPRSS2 cells maintained stable TMPRSS2 expression after 20 successive passages. Cell counting kit-8 (CCK-8) assays confirmed that there was no significant difference in proliferative activity between LLC-MK2/TMPRSS2 cells and LLC-MK2 cells. Viral replication capability testing showed that the laboratory-adapted strain of HPIV3 (ATCC strain) exhibited exponential growth in both LLC-MK2 and LLC-MK2/TMPRSS2 cells in culture without exogenous trypsin. Notably, LLC-MK2/TMPRSS2 cells significantly supported the replication of clinical HPIV3 isolates (circulating strain), whereas LLC-MK2 cells failed to sustain their infectivity effectively.Conclusions:In this study, we successfully generated the LLC-MK2/TMPRSS2 cell line using the PB transposon system to stably express TMPRSS2. Our TMPRSS2-transfected cell line enables the efficient isolation and propagation of HPIVs in vitro, eliminating the need for exogenous trypsin and providing a vital technical platform for isolating HPIVs and studying their pathogenicity.

Objective:To construct a nanoparticle vaccine displaying the prefusion F (preF) protein of respiratory syncytial virus (RSV) using the I53-50 protein nanoparticle platform, and to systematically evaluate its immunogenicity and protective efficacy.Methods:The RSV preF trimer antigen was genetically fused to I53-50A and assembled in vitro with I53-50B to form preF-I53-50 nanoparticles, theoretically displaying 20 preF antigens per particle. The structure and purity were characterized by size-exclusion chromatography, SDS-PAGE, and negative-stain electron microscopy. BALB/c mice were intramuscularly immunized with varying doses (1 μg or 5 μg) of preF antigen or an equimolar amount of preF-I53-50 nanoparticles. Humoral immunity, B-cell responses, and protective efficacy were assessed following intranasal viral challenge.Results:The preF-I53-50 nanoparticles self-assembled into spherical structures (50-60 nm in diameter) with uniformly arrayed antigens. The nanoparticle vaccine enhanced RSV-specific IgG1 and IgG2a antibody responses, promoting a Th1-biased immune profile. At equimolar preF doses, the neutralizing antibody titers induced by 1 μg and 5 μg nanoparticle formulations were 2.8-fold and 2.3-fold higher, respectively, than those elicited by preF alone ( P<0.05). Notably, even the low-dose nanoparticle group outperformed the high-dose preF group (1.6-fold increase). Viral challenge experiments demonstrated that preF-I53-50 effectively suppressed pulmonary viral replication, mitigated pathological damage, and induced stronger germinal center and memory B-cell responses, suggesting enhanced B-cell affinity maturation and long-term immune memory. Conclusion:The preF-I53-50 vaccine improves the immunogenicity and protective efficacy of RSV preF through multivalent antigen display.

The aim of this investigation was to determine the optimal storage medium for testicular hypothermic transportation and identify the ideal concentration for the application of the protective agent 5-aminolevulinic acid (5-ALA). Furthermore, this study aimed to explore the underlying mechanism of the protective effects of 5-ALA. First, we collected and stored mouse testicular fragments in different media, including Hank's balanced salt solution (HBSS; n = 5), Dulbecco's Modified Eagle Medium/Nutrient Mixture F-12 (DMEM/F12; n = 5), and alpha-minimum essential medium (αMEM; n = 5). Storage of testicular tissue in HBSS preserved the integrity of testicular morphology better than that in the DMEM/F12 group ( P < 0.05) and the αMEM group ( P < 0.01). Testicular fragments were subsequently placed in HBSS with various concentrations of 5-ALA (0 [control], 1 mmol l -1 , 2 mmol l -1 , and 5 mmol l -1 ) to determine the most effective concentration of 5-ALA. The 2 mmol l -1 5-ALA group ( n = 3) presented the highest positive rate of spermatogonial stem cells compared with those in the control, 1 mmol l -1 , and 5 mmol l -1 5-ALA groups. Finally, the tissue fragments were preserved in HBSS with control ( n = 3) and 2 mmol l -1 5-ALA ( n = 3) under low-temperature conditions. A comparative analysis was performed against fresh testes ( n = 3) to elucidate the underlying mechanism of 5-ALA. Gene set enrichment analysis (GSEA) for WikiPathways revealed that the p38 mitogen-activated protein kinase (MAPK) signaling pathway was downregulated in the 2 mmol l -1 5-ALA group compared with that in the control group (normalized enrichment score [NES] = -1.57, false discovery rate [FDR] = 0.229, and P = 0.019). In conclusion, these data suggest that using 2 mmol l -1 5-ALA in HBSS effectively protected the viability of spermatogonial stem cells upon hypothermic transportation.
Male ; Animals ; Testis/cytology* ; Aminolevulinic Acid/pharmacology* ; Mice ; Organ Preservation/methods* ; Organ Preservation Solutions/pharmacology* ; Cryopreservation/methods*

OBJECTIVES: To analyze the potential causal relationship between gut microbiota and food allergy (FA) using two-sample Mendelian randomization (MR) methods. METHODS: Data from genome-wide association studies on gut microbiota and FA were utilized. MR analysis was conducted employing inverse variance weighting, MR-Egger regression, and weighted median methods to assess the causal relationship between gut microbiota and FA. Cochrane's Q test was used to evaluate heterogeneity of instrumental variables, MR-PRESSO analysis was conducted to test for outliers and pleiotropy, and MR-Egger regression was employed to assess horizontal pleiotropy. The "leave-one-out" method was used to evaluate the impact of removing individual single nucleotide polymorphisms on the causal relationship. RESULTS: Inverse variance weighting analysis revealed that the phylum Verrucomicrobia, family Verrucomicrobiaceae, order Verrucomicrobiales, genus Ruminococcaceae UCG013, and genus Akkermansia were negatively associated with FA (P<0.05). Sensitivity analyses confirmed the reliability of the findings, indicating no heterogeneity or pleiotropy present. CONCLUSIONS There is a causal relationship between gut microbiota and FA, with Verrucomicrobia, Verrucomicrobiaceae, Verrucomicrobiales, Ruminococcaceae UCG013, and Akkermansia potentially reducing the risk of developing FA. These findings provide potential targets for the treatment and prevention of FA; however, further research is needed to explore the specific mechanisms by which the microbiota influence FA.
Humans ; Mendelian Randomization Analysis ; Gastrointestinal Microbiome ; Food Hypersensitivity/microbiology* ; Genome-Wide Association Study ; Polymorphism, Single Nucleotide

OBJECTIVES: To identify risk factors for recurrent plastic bronchitis (PB) among children with Mycoplasma pneumoniae pneumonia (MPP). METHODS: The clinical data of children with MPP complicated by PB who underwent bronchoscopy at Gansu Province Maternity and Child Health Hospital between July 2023 and January 2025 were retrospectively analyzed. Patients were grouped into a single-episode PB group and a recurrent PB group according to the number of PB episodes. Multivariable logistic regression was used to identify risk factors for recurrent PB. Receiver operating characteristic (ROC) curve analysis was used to assess the diagnostic performance of individual and combined predictors. RESULTS: A total of 264 children were included; 188 (71.2%) had a single episode of PB and 76 (28.8%) had recurrent PB. Multivariable logistic regression analysis showed that decreased serum albumin, atelectasis, and fever persisting beyond 72 hours after the initial bronchoscopy were significantly associated with recurrent PB (all P<0.05). The combination of these predictors yielded a sensitivity of 82.9%, specificity of 61.7%, and an area under the ROC curve of 0.777 (95%CI: 0.714-0.839), outperforming any single predictor (P<0.05). CONCLUSIONS In children with MPP complicated by PB, decreased serum albumin, the presence of atelectasis, and fever persisting beyond 72 hours after the initial bronchoscopy are associated with an increased risk of PB recurrence. In such cases, early repeat or multiple bronchoscopic interventions should be considered.
Humans ; Pneumonia, Mycoplasma/complications* ; Male ; Female ; Risk Factors ; Recurrence ; Child, Preschool ; Bronchitis/etiology* ; Child ; Retrospective Studies ; Logistic Models ; Infant ; ROC Curve ; Adolescent

BACKGROUND: Low serum albumin levels are established predictors of adverse outcomes in various cardiovascular conditions. However, the role of serum albumin in mortality among elderly patients with chronic aortic regurgitation (AR) has not been thoroughly investigated. This study aims to assess the relationship between serum albumin levels and mortality in this specific patient population. METHODS: Our analysis included 873 elderly AR patients from the China Valvular Heart Disease study, with baseline serum albumin measured at enrollment. Mortality outcomes were monitored for two years post-enrollment, employing a Cox proportional hazards model with a two-piecewise Cox proportional hazards framework to investigate the nonlinear relationship between serum albumin levels and all-cause mortality. RESULTS: During the 2-year follow-up period, we observed 63 all-cause deaths. The association between serum albumin levels and all-cause mortality displayed an approximating L-shaped curve, indicating a mortality threshold at 35 g/L. For serum albumin levels below 35 g/L, each 1 g/L decrease was associated with a 25% higher risk of all-cause mortality (HR = 1.25, 95% CI: 1.07-1.45). In contrast, no significant change in mortality risk was observed when serum albumin levels were greater than or equal to 35 g/L. Moreover, when serum albumin is classified as hypoproteinemia (serum albumin < 35 g/L), the higher risks of all-cause death were observed in hypoproteinemic patients (HR = 2.93, 95% CI: 1.50-5.74). More importantly, the association between serum albumin and death was significantly stronger in overweight/obese patients (≥ 24 kg/m² vs. < 24 kg/m², P _interaction = 0.006). CONCLUSIONS In elderly patients with AR, serum albumin levels showed an approximating L-shaped relationship with all-cause death, with thresholds of 35 g/L. Body mass index was significant effect modifiers of the association. These results suggest that serum albumin, as an inexpensive and readily available biochemical marker, may further improve the stratified risk of mortality in older AR patients.

BACKGROUND: Based on the China-VHD database, this study sought to develop and validate a Valvular Heart Disease- specific Age-adjusted Comorbidity Index (VHD-ACI) for predicting mortality risk in patients with VHD. METHODS & RESULTS: The China-VHD study was a nationwide, multi-centre multi-centre cohort study enrolling 13,917 patients with moderate or severe VHD across 46 medical centres in China between April-June 2018. After excluding cases with missing key variables, 11,459 patients were retained for final analysis. The primary endpoint was 2-year all-cause mortality, with 941 deaths (10.0%) observed during follow-up. The VHD-ACI was derived after identifying 13 independent mortality predictors: cardiomyopathy, myocardial infarction, chronic obstructive pulmonary disease, pulmonary artery hypertension, low body weight, anaemia, hypoalbuminaemia, renal insufficiency, moderate/severe hepatic dysfunction, heart failure, cancer, NYHA functional class and age. The index exhibited good discrimination (AUC, 0.79) and calibration (Brier score, 0.062) in the total cohort, outperforming both EuroSCORE II and ACCI (P < 0.001 for comparison). Internal validation through 100 bootstrap iterations yielded a C statistic of 0.694 (95% CI: 0.665-0.723) for 2-year mortality prediction. VHD-ACI scores, as a continuous variable (VHD-ACI score: adjusted HR (95% CI): 1.263 (1.245-1.282), P < 0.001) or categorized using thresholds determined by the Yoden index (VHD-ACI ≥ 9 vs. < 9, adjusted HR (95% CI): 6.216 (5.378-7.184), P < 0.001), were independently associated with mortality. The prognostic performance remained consistent across all VHD subtypes (aortic stenosis, aortic regurgitation, mitral stenosis, mitral regurgitation, tricuspid valve disease, mixed aortic/mitral valve disease and multiple VHD), and clinical subgroups stratified by therapeutic strategy, LVEF status (preserved vs. reduced), disease severity and etiology. CONCLUSION The VHD-ACI is a simple 13-comorbidity algorithm for the prediction of mortality in VHD patients and providing a simple and rapid tool for risk stratification.

Neuroinflammatory responses play an important role in the pathogenesis of various diseases, particularly those affecting the central nervous system. Inhibition of neuroinflammation is a crucial therapeutic strategy for the management of central nervous system disorders. The intestinal microbial-gut-brain axis serves as a key regulatory pathway that modulates neuroinflammatory processes. Intestinal flora metabolites such as short-chain fatty acids, indoles and their derivatives, lipopolysaccharides, trimethylamine oxide, and secondary bile acids exert direct or indirect effects on neuroinflammation. Studies have shown that electroacupuncture (EA) modulates the composition of the intestinal microbiota and its metabolites, while also suppressing neuroinflammation by targeting the TLR4/NF- κ B, NLRP3/caspase-1, and microglial cell M2-type transformation pathways. This review discusses the mechanisms by which EA regulates neuroinflammation via intestinal microbiota and its metabolites, providing information and a foundation for further investigation of the precise therapeutic mechanisms of EA in neurological disorders.
Humans ; Gastrointestinal Microbiome ; Electroacupuncture ; Neuroinflammatory Diseases/metabolism* ; Animals

[This corrects the article DOI: 10.1016/j.apsb.2022.05.019.].

Patients suffering from nerve injury often experience exacerbated pain responses and complain of memory deficits. The dorsal hippocampus (dHPC), a well-defined region responsible for learning and memory, displays maladaptive plasticity upon injury, which is assumed to underlie pain hypersensitivity and cognitive deficits. However, much attention has thus far been paid to intracellular mechanisms of plasticity rather than extracellular alterations that might trigger and facilitate intracellular changes. Emerging evidence has shown that nerve injury alters the microarchitecture of the extracellular matrix (ECM) and decreases ECM rigidity in the dHPC. Despite this, it remains elusive which element of the ECM in the dHPC is affected and how it contributes to neuropathic pain and comorbid cognitive deficits. Laminin, a key element of the ECM, consists of α-, β-, and γ-chains and has been implicated in several pathophysiological processes. Here, we showed that peripheral nerve injury downregulates laminin β1 (LAMB1) in the dHPC. Silencing of hippocampal LAMB1 exacerbates pain sensitivity and induces cognitive dysfunction. Further mechanistic analysis revealed that loss of hippocampal LAMB1 causes dysregulated Src/NR2A signaling cascades via interaction with integrin β1, leading to decreased Ca²⁺ levels in pyramidal neurons, which in turn orchestrates structural and functional plasticity and eventually results in exaggerated pain responses and cognitive deficits. In this study, we shed new light on the functional capability of hippocampal ECM LAMB1 in the modulation of neuropathic pain and comorbid cognitive deficits, and reveal a mechanism that conveys extracellular alterations to intracellular plasticity. Moreover, we identified hippocampal LAMB1/integrin β1 signaling as a potential therapeutic target for the treatment of neuropathic pain and related memory loss.
Animals ; Laminin/genetics* ; Hippocampus/metabolism* ; Neuralgia/metabolism* ; Cognitive Dysfunction/etiology* ; Male ; Peripheral Nerve Injuries/metabolism* ; Extracellular Matrix/metabolism* ; Integrin beta1/metabolism* ; Pyramidal Cells/metabolism* ; Signal Transduction