It has been 100 years since the 1918 influenza pandemic but influenza is still an uncontrolled infectious disease. In some developed countries, the coverage rate of influenza vaccine can reach as high as 60%-70%, and even up to 90% or higher in some specific population, such as the elderly and healthcare workers. The coverage rate of influenza vaccination in Chinese people, however, is very low, only about 2%-3% per year. The limitations of influenza vaccine, and the purpose and significance of influenza vaccination, the imbalance of vaccine information and the importance of inoculation for healthcare workers are discussed in this paper. The resistance to popularize influenza vaccination is explored from different perspectives. It is hoped that more people will recognize the objective epidemiological data, and get rid of misunderstandings based on their experiences. Healthcare workers in particular, and the general population, should be encouraged to have an influenza vaccination.

Primary mitochondrial disease is the most common inborn error of metabolism and is highly heterogeneous in terms of clinical manifestations and inheritance pattern. It has high mortality and disability rates. Multiple systems are often involved in this disease, and it is necessary to perform comprehensive evaluation and multidisciplinary management. The Mitochondrial Medicine Society issued the standard for the management of patients with primary mitochondrial disease:consensus statements from the Mitochondrial Medicine Society in 2017. The statements provided recommendations based on such consensus to guide the management and care of patients. This article interprets and summarizes the screening of organs and systems commonly involved in primary mitochondrial disease and the management of patients according to the consensus.

Objective To study the clinical features and prognosis of bronchopulmonary dysplasia (BPD) complicated by pulmonary hypertension (PH) in preterm infants. Methods A retrospective analysis was performed on the clinical data of 191 preterm infants with BPD. Results In the 191 preterm infants with BPD, 37 (19.4%), all with moderate or severe BPD, developed PH beyond 36 weeks' corrected age. The incidence rates of PH in infants with moderate and severe BPD were 5.7% (5/87) and 47.8% (32/67) respectively. Gestational age and birth weight were lower in infants with PH than in those without PH (P < 0.01). Infants with PH had higher incidence rates of small for gestational age (SGA), severe BPD, surgical ligation of patent ductus arteriosus (PDA), neonatal respiratory distress syndrome, hemodynamically significant PDA, and pneumonia than those without PH (P < 0.01). Durations of oxygen therapy, intubation, and positive pressure ventilation were longer in infants with PH than in those without PH (P < 0.01). Infants with PH had higher incidence rates of retinopathy of prematurity and extrauterine growth retardation, a higher mortality, and a longer length of hospital stay compared with those without PH (P < 0.01). In the 37 infants with PH (6 with mild PH, 14 with moderate PH, and 17 with severe PH), those with mild or moderate PH all survived; 15(88%) out of 17 infants with severe PH died. Conclusions The incidence of PH is high in preterm infants with moderate or severe BPD. Regular screening of pulmonary artery pressure is recommended for infants with BPD. Infants with low gestational age and birth weight, SGA, and severe BPD are more likely to develop PH. Infants with BPD complicated by PH have relatively high incidence rates of complications, high mortality, and poor prognosis.

Objective To systematically evaluate the clinical efficacy of nasal high-frequency ventilation (nHFV) in the treatment of neonatal respiratory distress syndrome (NRDS). Methods A literature search was performed in PubMed, Cochrane Library, EMBase (Ovid), Chinese Biomedical Literature Database, Chinese Journal Full-text Database, Wanfang Data, and Weipu Data to collect the randomized controlled trials (RCTs) that compared the clinical efficacy of nHFV and nasal continuous positive airway pressure (nCPAP) in the treatment of NRDS. A Meta analysis was performed on the included RCTs using Rev Man 5.3 software after data extraction and quality evaluation by Cochrane 5.1.0. Results A total of 4 RCTs involving 218 patients were included. The Meta analysis showed that compared with the nCPAP group, the nHFV group had a significantly better treatment outcome (RR=1.73, 95% CI:1.39-2.15, P < 0.00001). There were no significant differences in the incidence rates of intraventricular hemorrhage, periventricular leukomalacia, bronchopulmonary dysplasia, necrotizing enterocolitis, pneumothorax and retinopathy of prematurity. Conclusions Compared with nCPAP, nHFV has better clinical efficacy in the treatment of NRDS, without increasing the risk of related complications.

Objective To find out the prevalence of respiratory syncytial virus (RSV) genotypes in southern Zhejiang Province, China, and to study the genetic characteristics of G protein from subtype A of RSV. Methods The lower respiratory tract secretions of children under 5 years of age who were hospitalized for pneumonia and bronchiolitis in three hospitals in southern Zhejiang Province from July 2009 to June 2014 were collected. Direct immunofluorescence assay was used to detect RSV antigens from the collected secretions. A total of 200 samples were randomly selected from RSV-positive specimens in each prevailing year (from July of a specific year to June of the next year). RT-PCR was used to determine RSV subtypes, and the near-full length gene sequence of G protein from subtype A was amplified and sequenced to identify the genotype. Results A total of 25449 samples of lower respiratory tract secretions were collected from 2009 to 2014, among which 6 416 (25.21%) samples were RSV-positive. Among the 1 000 RSV-positive specimens randomly sampled, 462 strains (46.2%) were subtype A, and 538 strains (53.8%) were subtype B. Subtype A accounted for 22.5%, 74.5%, 84.5%, 19.0%, and 30.5% of the total strains in each year from 2009 to 2014. A total of 25 RSV subtype A strains were randomly sampled and sent out for bidirectional sequencing in each year, which confirmed 52 positive subtype A strains. Four genotypes of subtype A strains were obtained from the above strains, including NA1 (39 strains), NA4 (1 strain), ON1 (10 strains), and GA2 (2 strains). NA1 was the dominant genotype between 2009 and 2012, and ON1 was the only genotype of subtype A during 2013-2014. The nucleotide homology and amino acid homology between the G protein of subtype A and the prototype strain A2 were 80.7%-89.3% and 74.4%-82.6%, respectively. The nucleotide homology and amino acid homology between the isolates of subtype A were 81.5%-100% and 80.2%-100%, respectively. Conclusions In southern Zhejiang Province from 2009 to 2014, there was a co-circulation of RSV subtypes A and B, as well as a co-circulation of several different genotypes of RSV subtype A, which had highly variable G protein genes.

Objective To study the correlation of dynamic change in serum 25-hydroxy vitamin D[25(OH)D] level with the disease severity and related laboratory markers in infants/toddlers with severe pneumonia. Methods A total of 132 infants/toddlers with severe pneumonia who were hospitalized between March 2017 and March 2018 were enrolled as the severe pneumonia group. According to the disease severity on admission and after one week of treatment, they were further divided into non-critical group (41 children on admission and 78 after one week of treatment), critical group (59 children on admission and 35 after one week of treatment), and extremely critical group (32 children on admission and 19 after one week of treatment). A total of 142 infants/toddlers who underwent physical examination during the same period of time were enrolled as the healthy control group. The serum levels of 25(OH)D, procalcitonin (PCT), and N-terminal pro-brain natriuretic peptide (NT-proBNP) were measured on admission and after one week of treatment for the severe pneumonia group, and the serum level of 25(OH)D was measured on admission for the healthy control group. According to the 25(OH)D level after one week of treatment, the children with severe pneumonia were divided into increased vitamin D (VD) group with 81 children and reduced VD group with 51 children, and a comparative analysis and a correlation analysis were performed. Results The severe pneumonia group had a significantly lower mean 25(OH)D level than the healthy control group (P < 0.05), and all the three subgroups of different severities had significantly lower 25(OH)D level than the healthy control group (P < 0.05). On admission and after one week of treatment, the non-critical group had a significantly higher 25(OH)D level than the critical and extremely critical groups (P < 0.01), and the critical group had a significantly higher 25(OH)D level than the extremely critical group (P < 0.05). The extremely critical and critical groups had significantly higher serum levels of PCT and NT-proBNP than the non-critical group on admission and after one week of treatment (P < 0.05). After one week of treatment, compared with the reduced VD group, the increased VD group had a significantly less serious condition. At discharge, the increased VD group had a significantly better outcome compared with the reduced VD group (P < 0.01). In the children with severe pneumonia, the change value of serum 25(OH)D level after treatment was negatively correlated with the change values of PCT and NT-proBNP (r=-0.597 and -0.404 respectively; P < 0.01). Conclusions The change in VD level is correlated with the severity of severe pneumonia in infants/toddlers and can be used as an index for disease monitoring. VD supplementation may help with disease recovery.

Objective To study the clinical and laboratory features of children with Kawasaki disease (KD) aged > 5 years. Methods A retrospective analysis was performed for the clinical data of 250 elderly children (aged > 5 years) who were diagnosed with KD or incomplete KD (divided into 5-9 years and > 9 years groups) and 266 KD children aged 1-5 years. Clinical and laboratory features were compared between groups. Results The > 9 years group had the lowest incidence rates of hand and foot swelling and fingertip or perianal desquamation (P < 0.05). The 5-9 years group had the highest incidence rate of neck lymph node enlargement (P < 0.05). The > 9 years group had the longest course of fever (P < 0.05). There were no significant differences among the three groups in the incidence rates of rash, bulbar conjunctival hyperaemia and the change in lips, the proportion of children with incomplete KD, and the proportion of children with no response to intravenous immunoglobulin (IVIG). The > 9 years group had the lowest platelet count and albumin (P < 0.05). The 5-9 years group had the highest percentage of neutrophils (P < 0.05). There were no significant differences among the three groups in white blood cell count, C-reactive protein, erythrocyte sedimentation rate, and alanine aminotransferase (P > 0.05). As for the degree of CAL, the 1-5 years group had the highest incidence of mild coronary dilation, and the > 9 years group had the highest incidence rate of moderate coronary aneurysm (P < 0.05). There was no significant difference in the incidence rate of large coronary aneurysm among the three groups (P > 0.05). Conclusions KD children aged > 5 years have atypical clinical manifestations, with a high incidence rate of neck lymph node enlargement, a high percentage of neutrophils, and a low level of albumin and platelet. The risk of moderate coronary aneurysm increases with age.

Kallmann syndrome (KS) is a rare pediatric disease with major manifestations of olfactory dysfunction and hypogonadotropic hypogonadism. Five children (4 boys and 1 girl) with KS reported in this article were aged between 6 months and 19 years at the time when they attended the hospital. All the children had the clinical manifestation of hypogonadotropic hypogonadism; in addition, three children had olfactory dysfunction (two were found to have olfactory bulb dysplasia on magnetic resonance imaging), one had cleft lip and palate, and one had micropenis and cryptorchidism with right renal agenesis during infancy. All the five children had normal karyotype and their parents had normal clinical phenotypes. The uncle of one child had underdeveloped secondary sexual characteristics and olfactory disorder since childhood. High-throughput sequencing found two known heterozygous missense mutations in the FGFR1 gene, i.e., c.1097C > T(p.P366L) and c.809G > C(p.G270A), in two children. One child had a novel frameshift mutation, c.1877_1887/p.S627Tfs^*6, in the KAL1 gene; this deletion mutation caused a frameshift in base sequence and produced truncated proteins, which led to a significant change in protein structure, and thus it was highly pathogenic. It is concluded that KS has great clinical and genetic heterogeneity and can be accompanied by incomplete dominant inheritance and that gene detection helps with the diagnosis of this disease.

Objective To investigate the prevalence of simple obesity and its risk factors in preschool children in Fuzhou, China. Methods The physical examination data of 14 kindergartens in Fuzhou, China were collected by stratified cluster random sampling. The detection rate of simple obesity was calculated. The children with normal body weight were selected as the control group by 1:1 case-control method. The risk factors for childhood simple obesity were investigated by self-made questionnaire and multivariate logistic regression analysis. Results A total of 5767 children aged 3-6 years were enrolled in this study. A total of 289 (5.01%) children with simple obesity were screened out, including 153 with mild obesity and 136 with moderate to severe obesity. The prevalence rate of simple obesity gradually increased with the age of children. The multivariate logistic regression analysis showed that the following factors were independent risk factors for simple obesity:preference for fried food (OR=4.789, P < 0.05), caregivers' over-concern about diet (OR=4.620, P < 0.05), eating before sleep (OR=4.006, P < 0.05), eating fast (OR=3.221, P < 0.05), preference for sweets (OR=2.282, P < 0.05), high birth weight (OR=2.202, P < 0.05), overweight or obesity in father (OR=2.074, P < 0.05), overweight or obesity in mother (OR=2.047, P < 0.05), more than 1.2 times the food intake at the same age (OR=2.013, P < 0.05), watching TV (OR=1.665, P < 0.05), and lack of exercise (OR=1.463, P < 0.05). Conclusions The prevalence rate of simple obesity is 5.01% in preschool children in Fuzhou, China. The development of simple obesity is multifactorial. It is suggested that doctors, parents, and teachers should strengthen health education for preschool children, help them develop good living and eating habits, and encourage them to take more exercise, in order to reduce the development of simple obesity.

Objective To study the interactive regulatory effect of histone acetylation and methylation on cardiomyogenesis, and to provide a theoretical basis for the prevention and treatment of congenital heart disease. Methods A total of 24 Kunming mice were randomly divided into embryo day 14.5 (ED 14.5) group, embryo day 16.5 (ED 16.5) group, postnatal day 0.5 (PND 0.5) group, and postnatal day 7 (PND 7) group, with 6 mice in each group, and the heart tissue of fetal and neonatal mice was collected. Colorimetry was used to measure the activities of histone acetylases (HATs) and histone methyltransferases (HMTs) in the myocardium. Western blot was used to measure the expression of H3K9ac and H3K9me3 in the myocardium. Results Colorimetry showed that the activities of HATs and HMTs were higher before birth and were lower after birth. There was a significant difference in the activity of HATs in the myocardium between the PND 0.5 and PND 7 groups and the ED 14.5 group (P < 0.05), as well as between the PND 7 group and the ED 16.5 group (P < 0.05). There was also a significant difference in the activity of HMTs in the myocardium between the PND 7 group and the ED 14.5 and ED 16.5 groups (P < 0.05). Western blot showed higher expression of H3K9ac and H3K9me3 before birth and lower expression of H3K9ac and H3K9me3 after birth, and there were significant differences in the expression H3K9ac and H3K9me3 in the myocardium between the PND 0.5 and PND 7 groups and the ED 14.5 and ED 16.5 groups (P < 0.05). Conclusions The dynamic expression of HATs, HMTs, H3K9ac, and H3K9me3 is observed during cardiomyogenesis, suggesting that histone H3K9ac acetylation and histone H3K9me3 methylation mediated by HATs and HMTs may play a role in interactive regulation during cardiomyogenesis.

Juvenile myelomonocytic leukemia (JMML) is a rare chronic myeloid leukemia in children and has the features of both myelodysplastic syndrome and myeloproliferative neoplasm. It is highly malignant and has a poor treatment outcome. Children with JMML have a poor response to conventional chemotherapy. At present, hematopoietic stem cell transplantation is the only possible cure for this disease. In recent years, significant progress has been made in targeted therapy for mutant genes in the Ras signaling pathway and demethylation treatment of aberrant methylation of polygenic CpG islands. This article reviews the treatment and efficacy evaluation of JMML.

The etiology and pathogenesis of autism spectrum disorder (ASD) are not yet clear. Studies have shown that there are many neurotransmitter abnormalities in children with ASD, mainly involving in glutamate, γ-aminobutyric acid (GABA), dopamine, 5-HT and oxytocin. The imbalance of excitatory glutamatergic neurotransmitters and inhibitory GABAergic neurotransmitters is closely related to the pathogenesis of ASD. Both animal model studies and clinical studies on ASD suggest that GABA signaling pathway may play an important role in the pathogenesis of ASD. This article reviews the research on the association between GABA signaling pathway and the pathogenesis of ASD to further explore the pathogenesis of ASD and provide theoretical basis for the treatment of ASD.