[Objective] To explore the accuracy and feasibility of non-invasive prenatal diagnosis of fetal RhE genotype using cell-free fetal DNA (cff-DNA) from maternal peripheral blood. [Methods] A total of 134 pregnant women with single fetuses and RhE-negative blood group were selected from our hospital from November 2023 to August 2024. Free DNA extraction kit was used to extract free DNA from peripheral blood of pregnant women, and the RhE blood group genotype of free DNA was detected by real-time fluorescent quantitative PCR (RT-qPCR). If the qPCR amplification signal of the sample was negative, the methylated RASSF1A gene was amplified, and the positive amplification result was used as a sign of successful extraction of cff-DNA. Serological microcolumn gel method was used to detect the phenotype of RhE blood group in neonatal peripheral blood. [Results] Among the 134 maternal peripheral blood samples, the cff-DNA detection of RhE blood group phenotypes was consistent with the RhE blood group genotyping of neonatal peripheral blood in 133 cases, including 90 cases of Rhee genotype and 43 cases of RhE genotype, with diagnostic concordance rate of 99.3%, sensitivity of 97.7%, specificity of 100%, youden index of 0.977, area under ROC curve of 0.995, the Kappa value of 0.983, positive predictive value of 100%, and negative predictive value of 98.9%. The sample of 1 case failed to be detected. After the amplification of methylated RASSFIA gene, it was confirmed that the reason for the failure was that no cff-DNA was extracted from the sample. The diagnostic concordance rates of the first, second and third trimesters were 93.8% (15/16), 100% (51/51) and 100% (67/67), respectively. Fisher's exact test method was used to calculate the P value, which was P>0.05, indicating that there was no statistical significance in the difference of diagnostic concordance rate among the three pregnancy periods, and there was no difference in the detection concordance rate of this method in different pregnancy periods. [Conclusion] The use of cff-DNA in maternal peripheral blood for the detection of fetal RhE blood group genotype is an accurate and highly feasible non-invasive prenatal diagnostic method, which is helpful for the clinical diagnosis of fetal and neonatal hemolytic disease caused by anti-E antibody.

This study aims to establish a high-performance size-exclusion chromatography (HPSEC) method for determining the content of the classical swine fever virus (CSFV) E2 protein and screen the optimal stabilizer to enhance the stability of this protein. The optimal detection conditions were determined by optimizing the composition of the mobile phase, and characteristic chromatographic peaks were identified by SDS-PAGE and Western blotting. The specificity, repeatability, precision, linearity, limit of detection (LOD), and limit of quantitation (LOQ) of the method were assessed. The method established was used to determine the content of CSFV E2 protein antigen and vaccine. Differential scanning fluorimetry (DSF) was employed to screen the buffer system, pH, and salt ion concentrations, and sugar, amino acid, and alcohol stabilizers were further screened. The results showed that using a 200 mmol/L phosphate buffer provided the best column efficiency. An antigen-specific chromatographic peak appeared at the retention time of 18 min, which was identified as the CSFV E2 protein by SDS-PAGE and Western blotting. The method exhibited high specificity for detecting the CSFV E2 protein, with no absorbance peak observed in the blank control. The relative standard deviation (RSD) of the peak area for six repeated injections of the CSFV E2 protein was 0.74%, indicating good repeatability of the method. The RSD for repeated detection of two different concentrations of CSFV E2 protein samples by different operators at different time points was less than 2%, suggesting good intermediate precision of the method. The peak area of the CSFV E2 protein was linearly related to its concentration, with the regression equation showing R² of 1.000. The LOD and LOQ of the method were 14.88 μg/mL and 29.75 μg/mL, respectively. Application of the developed method in the detection of three batches of CSFV E2 protein antigen and three batches of vaccine demonstrated results consistent with those from the bicinchoninic acid (BCA) assay, which meant that the method could accurately determine the content of CSFV E2 protein antigen and vaccine. The DSF method identified 50 mmol/L Tris-HCl at pH 8.0 as the optimal buffer, and the addition of sugar and alcohol stabilizers further improved the stability of the CSFV E2 protein. The HPSEC method established in this study is simple, fast, and exhibits good accuracy and repeatability, enabling precise measurement of the CSFV E2 protein content. It is expected to play a crucial role in the quality control of the CSFV E2 vaccine. Furthermore, the strategy for improving the CSFV E2 protein stability, identified through DSF screening, has significant implications for enhancing the stability of the CSFV E2 vaccine.
Classical Swine Fever Virus/chemistry* ; Chromatography, Gel/methods* ; Animals ; Swine ; Viral Envelope Proteins/immunology*

Objective:To investigate the protective effect of quercetin against LasB-induced apoptosis, inflammation, and oxidative stress in THP-1 macrophages, providing valuable insights into the use of quercetin as a virulence inhibitor for Pseudomonas aeruginosa infection treatment. Methods:This was an experimental study. The experimental strain was the standard strain. The LasB protein was obtained utilizing protein recombination technology, while the enzyme activity of LasB was assessed through both the Elastin Congo red assay and fluorescently labelled elastin assay. The LasB-induced THP-1 macrophage infection model was established, and quercetin was utilized for intervention. Cell viability was evaluated via CCK-8 assay, while cell morphology was observed under an inverted microscope. Apoptosis detection involved employing both TUNEL and Annexin V/PI staining. The mRNA expression and protein levels of inflammatory cytokines and COX-2 were determined by RT-qPCR and ELISA respectively. Intracellular ROS levels were quantified using the DCFH-DA fluorescent probe. One-way ANOVA was used for statistical analysis, and Tukey test was used for multiple comparisons. Results:The pLasB with a molecular weight of 33 000 and acceptable enzymatic activity (purity>90%), was successfully obtained. THP-1 macrophages treated with pLasB at a concentration of 100 μg/ml presented significantly decreased viability and integrity rate when compared with the normal control group. Additionally, pLasB promoted apoptosis, up-regulated the levels of inflammatory cytokines IL-1α, IL-1β, IL-6, IL-10, IL-12, and TNF-α, increased intracellular ROS fluorescence intensity, and elevated COX-2 mRNA expression level. Furthermore, the viability of THP-1 macrophages was significantly enhanced under quercetin intervention at concentrations of 2.5 μmol/L, 5 μmol/L and 10 μmol/L. The apoptosis rate exhibited a significant reduction from 18.32%±0.17% to 13.17%±0.20%, 11.43%±0.06% and 7.74%±0.04%, respectively ( F=1 679, P<0.05). There was a notable down-regulation of pro-inflammatory cytokines IL-1α, IL-1β, IL-6, IL-12 and TNF-α while the anti-inflammatory cytokine IL-10 showed a significant up-regulation. Both intracellular ROS fluorescence intensity ( F=86.92, P<0.05) and COX-2 level ( F=24.62, P<0.05) demonstrated a substantial decrease. Conclusion:Quercetin demonstrates significant efficacy in inhibiting LasB-induced apoptosis, inflammation, and oxidative stress in THP-1 macrophages, which highlights immense potential as a potent virulence inhibitor of Pseudomonas aeruginosa.

Objective:To summarize the clinical and prognostic features of children with opsoclonus-myoclonus-ataxia syndrome (OMAS).Methods:A total of 46 patients who met the diagnostic criteria of OMAS in the Department of Neurology, Beijing Children′s Hospital from June 2015 to June 2023 were retrospectively analyzed. Centralized online consultations or telephone visits were conducted between June and August 2023. The data of the children during hospitalization and follow-up were collected, including clinical manifestations, assistant examination, treatment and prognosis. According to the presence or absence of tumor, the patients were divided into two groups. The chi-square test or Mann-Whitney U test was used to compare the differences between the two groups. Univariate Logistic regression was used to analyze the factors related to OMAS recurrence and prognosis. Results:There were 46 patients, with 25 males and the onset age of 1.5 (1.2, 2.4) years. Twenty-six (57%) patients were diagnosed with neuroblastoma during the course of the disease, and no patients were categorized into the high-risk group. A total of 36 patients (78%) were followed up for≥6 months, and all of them were treated with first-line therapy with glucocorticoids, gammaglobulin and (or) adrenocorticotrophic hormone. Among the 36 patients, 9 patients (25%) were treated with second-line therapy for ≥3 months, including rituximab or cyclophosphamide, and 17 patients (47%) received chemotherapy related to neuroblastoma. At the follow-up time of 4.2 (2.2, 5.5) years, 10 patients (28%) had relapsed of OMAS. The Mitchell and Pike OMS rating scale score at the final follow-up was 0.5 (0, 2.0). Seven patients (19%) were mildly cognitively behind their peers and 6 patients (17%) were severely behind. Only 1 patient had tumor recurrence during follow-up. The history of vaccination or infection before onset was more common in the non-tumor group than in the tumor group (55%(11/20) vs. 23%(6/26), χ2=4.95, P=0.026). Myoclonus occurred more frequently in the non-tumor group (40%(8/20) vs. 4%(1/26), χ2=7.23, P=0.007) as the onset symptom. Univariate Logistic regression analysis showed that the tumor group had less recurrence ( OR=0.19 (0.04-0.93), P=0.041). The use of second-line therapy or chemotherapy within 6 months of the disease course had a better prognosis ( OR=11.64 (1.27-106.72), P=0.030). Conclusions:OMAS in children mostly starts in early childhood, and about half are combined with neuroblastoma. Neuroblastoma in combination with OMAS usually has a low risk classification and good prognosis. When comparing patients with OMAS with and without tumors, the latter have a more common infection or vaccination triggers, and myoclonus, as the onset symptom, is more common. Early addition of second-line therapy is associated with better prognosis in OMAS.

Objective:To summarize the clinical and genetic characteristics of mental retardation disorder (MRD) with TRIO gene variant in children.Methods:Case series study. The data of 9 children with TRIO gene variants were collected retrospectively from August 2019 to March 2024 in Department of Neurology, Beijing Children′s Hospital, Capital Medical University and Department of Pediatrics, the Third Affiliated Hospital of Zhengzhou University. The data included gender, age, intellectual and motor development, appearance, seizures, neuroimaging and genetic results. The clinical features and genotype-phenotype correlations were summarized.Results:Of the 9 children, 6 boys and 3 girls, 4 MRD63 children presented with moderate to severe developmental delays accompanied by macrocephaly; 5 MRD44 children had mild to moderate developmental delays with microcephaly. A total of 5 children had dysmorphic facial features (flat occiput, thick eyebrows, unibrow, large ears, short fingers, pale skin, yellow hair, and strabismus), 2 children experienced seizures (1 child with myoclonic seizure and 1 with absence seizure), 4 children had feeding difficulties, 1 child had congenital cataracts, 1 child had congenital heart disease, 1 child had recurrent infections, and 1 child had tiger-striped changes in the fundus examination. TRIO gene variants carried by the 9 children were all de novo, involving 8 variant sites, including 7 missense variants and 1 frameshift variant, c.3232C>T/p.R1078W (2 cases), c.3920A>G/p.Y1307C, c.4112A>T/p.H1371L, c.4283G>T/p.R1428L, c.4394A>G/p.N1465S, c.6041T>C/p.I2014T, c.6821G>A/p.R2274H, c.7027delC/p.Q2343Sfs*70. Among them, 2 sites are located in the Spectrin domain, 4 sites are in the GEFD1 domain, 2 sites are in the GEFD2 domain, and 1 site (frameshift variant) is in the PH2-SH3 domain. The individual with frameshift variant exhibit absence seizures, mild developmental delay, and the mildest phenotype. The child with myoclonic seizures was treated with valproic acid and levetiracetam for seizure control, while the child with absence epilepsy was treated with valproic acid and lamotrigine for seizure control. All 9 children underwent regular rehabilitation exercises, making slow progress.Conclusions:TRIO gene related MRD is characterized by varying degrees of developmental delay, and often accompanied by macrocephaly or microcephaly, dysmorphic facial features, and with or without seizures. The main variant types are missense variants, which are mostly concentrated in the Spectran domain and GEFD domain. p. R1078W may be a relative hotspot variant. The phenotype caused by the frameshift variant is relatively milder.

Objective:To explore the risk factors for lymphoproliferative disorders (PTLD) in children with thalassemia major (TM) after allogeneic hematopoietic stem cell transplantation (allo-HSCT).Methods:This was a retrospective case-control study.A total of 482 children with TM who underwent allo-HSCT at Shenzhen Children′s Hospital between January 2020 and December 2022 were selected and classified into the PTLD and non-PTLD groups according to the occurrence of PTLD.The risk factors for PTLD after allo-HSCT in children with TM were analyzed, and the diagnostic efficiency of relevant risk factors for PTLD was analyzed by receiver operating characteristic (ROC) curve.Results:A total of 25 out of 482 patients (5.2%, 25/482) developed PTLD about 114 (54-271) days after allo-HSCT.Among them, 12 cases (12/25, 48.0%) occurred within 100 days, and 22 cases (22/25, 88.0%) occurred within 1 year after allo-HSCT.Univariate analysis showed that there were significant differences in gender composition, type of transplant donor, number of natural killer cells and B lymphocytes in peripheral blood at 30 days after allo-HSCT, positive rate of plasma Epstein-Barr virus deoxyribonucleic acid (EBV-DNA) and incidence rate of acute graft-versus-host disease (aGVHD) between the 2 groups (all P<0.05).Multivariate Logistic regression analysis showed that female ( OR=3.196, 95% CI: 1.144-8.929), positive plasma EBV-DNA ( OR=17.523, 95% CI: 5.449-56.344) and aGVHD ( OR=3.156, 95% CI: 1.161-8.575) were independent risk factors for PTLD after allo-HSCT in TM children (all P<0.05).The ROC curve analysis showed that positive plasma EBV-DNA had an excellent accuracy in predicting the occurrence of PTLD after allo-HSCT (sensitivity was 0.796, specificity was 0.800, area under the curve was 0.803).If combined with aGVHD and gender, the area under the curve for the prediction of PTLD increased to 0.831. Conclusions:Female, positive plasma EBV-DNA and aGVHD are independent risk factors for PTLD after allo-HSCT in children with TM.It provides useful early warnings for the prediction and prevention of PTLD.

Objective:To investigate the protective effect of quercetin against LasB-induced apoptosis, inflammation, and oxidative stress in THP-1 macrophages, providing valuable insights into the use of quercetin as a virulence inhibitor for Pseudomonas aeruginosa infection treatment. Methods:This was an experimental study. The experimental strain was the standard strain. The LasB protein was obtained utilizing protein recombination technology, while the enzyme activity of LasB was assessed through both the Elastin Congo red assay and fluorescently labelled elastin assay. The LasB-induced THP-1 macrophage infection model was established, and quercetin was utilized for intervention. Cell viability was evaluated via CCK-8 assay, while cell morphology was observed under an inverted microscope. Apoptosis detection involved employing both TUNEL and Annexin V/PI staining. The mRNA expression and protein levels of inflammatory cytokines and COX-2 were determined by RT-qPCR and ELISA respectively. Intracellular ROS levels were quantified using the DCFH-DA fluorescent probe. One-way ANOVA was used for statistical analysis, and Tukey test was used for multiple comparisons. Results:The pLasB with a molecular weight of 33 000 and acceptable enzymatic activity (purity>90%), was successfully obtained. THP-1 macrophages treated with pLasB at a concentration of 100 μg/ml presented significantly decreased viability and integrity rate when compared with the normal control group. Additionally, pLasB promoted apoptosis, up-regulated the levels of inflammatory cytokines IL-1α, IL-1β, IL-6, IL-10, IL-12, and TNF-α, increased intracellular ROS fluorescence intensity, and elevated COX-2 mRNA expression level. Furthermore, the viability of THP-1 macrophages was significantly enhanced under quercetin intervention at concentrations of 2.5 μmol/L, 5 μmol/L and 10 μmol/L. The apoptosis rate exhibited a significant reduction from 18.32%±0.17% to 13.17%±0.20%, 11.43%±0.06% and 7.74%±0.04%, respectively ( F=1 679, P<0.05). There was a notable down-regulation of pro-inflammatory cytokines IL-1α, IL-1β, IL-6, IL-12 and TNF-α while the anti-inflammatory cytokine IL-10 showed a significant up-regulation. Both intracellular ROS fluorescence intensity ( F=86.92, P<0.05) and COX-2 level ( F=24.62, P<0.05) demonstrated a substantial decrease. Conclusion:Quercetin demonstrates significant efficacy in inhibiting LasB-induced apoptosis, inflammation, and oxidative stress in THP-1 macrophages, which highlights immense potential as a potent virulence inhibitor of Pseudomonas aeruginosa.