Objective: To investigate the clinical features, treatment strategies and long term outcomes of children with anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis. Methods: The data of clinical features, auxiliary examinations, treatments and prognosis in children with anti-NMDAR encephalitis in Xiangya Hospital of Central South University from March 2014 to October 2017 were collected and retrospectively analyzed. A total of 71 patients were enrolled, including 33 males and 38 females. The youngest age of onset was 4 months old, and the age of onset was (9±4) years. The first-line immunotherapy treatment for anti-NMDAR encephalitis was short course corticosteroid (high-dose impulse therapy and oral maintenance therapy for 1 month in acute period) and (or) immunoglobulin. The clinical evaluation was performed 2 weeks after first-line immunotherapy treatment. The second-line immunotherapy treatment, including rituximab and (or) cyclophosphamide, would be started if the symptoms did not improve significantly and the modified Rankin scale (mRS) score ≥3. All patients were followed up and evaluated for prognosis. T-test, Mann-Whitney U, Chi square test and Fisher′s exact probability method were used for comparison between good outcome group and poor outcome group, first-line immunotherapy group and first-line immunotherapy combined with second-line immunotherapy group. Results: The more common clinical manifestations were psychiatric symptoms (n=61, 86%), dyskinesia (n=55, 77%) and convulsions (n=51, 72%). Two cases (3%) had tumors. Electroencephalogram (EEG), cerebro-spinal fluid (CSF) and brain magnetic resonance imaging (MRI) studies were abnormal in 83% (59/71), 39% (27/69) and 38% (27/71) patients, respectively. For the treatment regimens, all the 71 patients underwent first-line immunotherapy, resulting in improvement within 14 days in 40 cases (56%), and 1 case (1%) died. The rest 30 cases (42%) received second-line immunotherapy. The patients were followed up for 5.0-41.8 months, with a median of 19.3 months. At the last follow-up, 49 cases (69%) recovered completely, 15 cases (21%) had mild disability, 6 cases (8%) had severe disability, 1 case (1%) died and 3 cases (4%) had relapse. There were significant differences between the groups with good prognosis and poor prognosis on admission to pediatric intensive care unit (PICU) and consciousness disorder (10/64 vs. 5/7, 39/64 vs. 7/7, P=0.047, 0.004). There were significant differences between first-line immunotherapy group and the first-line combined second-line immunotherapy group on admission to PICU, consciousness disorder, sleep disorder and first mRS score (12% (5/41) vs. 33% (10/30), 44% (18/41) vs. 93% (28/30), 56% (23/41) vs. 90% (27/30), 3 (1-5) vs. 4 (3-5), respectively; χ²=4.645, 18.555, 9.560, Z=5.184, P=0.031, <0.01, 0.002, <0.01, respectively). Conclusions Anti-NMDAR encephalitis can occur in all ages of children. The most common clinical manifestations are psychotic symptoms, dyskinesia and convulsions. Paraneoplastic cases are less common in children. Immunotherapy is effective. The second-line immunotherapy should be given after the failure of first-line therapy (mRS score≥3).

Objective:To compare the differences between suspension and adherent cells of MDCK cell line in the isolation of influenza virus, and to explore the application prospects of MDCK cell suspension.Methods:Determination of viable cell density and cell specific growth rate were recorded by cell count. The WHO recommended vaccine strains were used for virus infection experiments. After five passages, hemagglutination titers were detected, while the sequencing analysis of their HA and NA genes revealed the mutation frequency.Results:The 24-hour and 48-hour viable cell density of the cell suspension was more stable than that of adherent cells. The cell suspension achieved an HA titer of 1∶256 or higher in the third generation, while adherent cells had no titer. In the fourth and fifth generations, one amino acid site mutation was found in the HA gene of H3N2 and BV subtypes of influenza virus cultured in the cell suspension, while no gene mutation was found in adherent cells in two passages. There were no mutations in the whole NA gene.Conclusions:Suspension of MDCK cells have more stable growth and higher efficiency in virus isolation than adherent cells, meanwhile there was a low rate of virus mutation during continuous passage. This study demonstrated the feasibility of this suspension of MDCK cells for influenza vaccine production based on cell culture technology.

Objective:To analyze the genetic and molecular characteristics of H9N2 subtype avian influenza viruses from external environment and humans in Anhui Province from 2013 to 2022.Methods:Environmental samples and human samples were collected from Anhui influenza surveillance network laboratory. Sixty-three strains of virus were isolated in chicken embryos. RT-PCR was used to amplify the virus and whole genome sequencing was performed. To construct gene evolutionary tree and analyze its genetic characteristics and potential glycosylation sites.Results:The hemagglutinin (HA) gene belongs to the 9.2.4.5 clade, and the protein cleavage sites are mostly " PSRSSR\GL". The neuraminidase (NA) gene, basic protein-1(PB1) gene, acidic protein (PA) gene, non-structural protein (NS) gene and nucleoprotein (NP) gene belong to the F/98 clade, the matrix protein (MP) gene belongs to the G1/97 clade, and the basic protein-2 (PB2) gene belongs to the ST/7488 clade. Mutations of T155N, R164Q, H183N, T189D/V, A190V/T and Q226L occurred in HA protein, deletion of NA protein occurred at 62-64 sites, and mutations of T271A, I292V/M and E627V/L occurred in PB2 protein. At the same time, mutations of K356R and S409N occurred in the PA protein.Conclusions:The H9N2 subtype avian influenza viruses collected from external environment and human sources in Anhui province from 2013 to 2022 belong to the same evolutionary branch, and amino acid site mutations suggest that the virus shows a tendency to gradually adapt to the mammalian host environment. Therefore, further studies on the adaptive evolution of the virus and related monitoring work are needed.

Objective: To investigate the effect of hypertensive disorder complicating pregnancy (HDCP) on the mortality and early complications of premature infants. Methods: The general clinical data of preterm infants with gestational age 24-36^{+ 6} weeks were collected from the cooperative units in the task group from January 1, 2013 to December 31, 2014.According to the severity of HDCP, the infants were divided into 4 groups: HDCP group, preeclampsia group, eclampsia group and non HDCP group, the mortality and major complications of preterm infants were compared, and the influencing factors were analyzed. Results: The mortality rate of preterm in the HDCP group was significantly higher than that of non HDCP group, and there was statistical significance (χ²=9.970, P=0.019). Eclampsia had a highest fatality rate (4.8%) in the early stage, compared with non HDCP group (2.2%), and the difference was statistically significant.Comparison of HDCP group (1.8%) and eclampsia group (3.2%) suggested that there was no statistically significant difference.The incidence of respiratory distress syndrome (RDS) in preterm in HDCP group was significantly higher than that of non HDCP group, and there was statistical significance (χ²=13.241, P=0.004). Eclampsia group showed the highest incidence (35.4%), compared with non HDCP group (16.2%), the difference was statistically significant, but compared with HDCP group (19.9%), preeclampsia group (17.1%), there was no significant diffe-rence.The incidence of bronchopulmonary dysplasia (BPD) in preterm in HDCP group was significantly higher than that of non HDCP group (χ²=9.592, P=0.022), the highest incidence showed up in eclampsia group (9.7%), compared with non HDCP group (2.0%) and HDCP group (1.7%), the difference was statistically significant.But there was no statistically significant difference, compared with preeclampsia group.As the degree of HDCP aggravated, the incidence of BPD gradually rose.There was no significant impact on necrotizing enterocolitis (NEC), retinopathy of prematurity (ROP), intraventricular hemorrhage (IVH) and sepsis of HDCP (χ²=7.054, 7.214, 0.358, 3.852; P=0.070, 0.065, 0.949, 0.278). Considering the overall outcome of the child, that was, whether the child died or survived, he had at least one complication, and HDCP had an effect on it (χ²=15.697, P=0.001), so the incidence increased while the degree of HDCP rose gradually.After adjusting gestational age, birth weight, sex, way of delivery, placental abruption and front placenta, prenatal hormonal, gestational diabetes, neonatal asphyxia and other factors, the results displayed that HDCP was the factor leading to the death of premature baby (OR=2.159, 95%CI: 1.093-4.266), and comparison between preeclampsia and eclampsia showed no statistical difference (P=0.714, 0.389); HDCP had no significant influence on RDS, BDP, ICH, NEC, ROP and sepsis. Conclusions HDCP leads to increased risk of premature death, but also leads to the increased incidence of RDS and BPD, but it had no obvious effect on NEC, ROP, IVH, sepsis and other complications.