Childhood asthma is the most common chronic airway inflammation disease. The phenotypes of childhood wheezing, early diagnosis of asthma and the difficulties in diagnosis, tailor-made treatment and monitoring are focus problems at present. Early diagnosis, tailor-made treatment and dynamic monitoring are key strategies of asthma control

OBJECTIVE: To investigate the changes in the levels of interleukin-17 (IL-17) and transforming growth factor beta 1 (TGF-β1) in serum and bronchoalveolar lavage fluid (BALF) and their clinical significance among children with asthma. METHODS: Fifty-six children with asthma were divided into moderate or severe asthma (n=37) and mild asthma groups (n=19) and 18 children without asthma were selected as the control group. Cells in BALF were counted under a microscope. The levels of IL-17 and TGF-β1 in serum and BALF were measured using ELISA. RESULTS: There were no significant differences in total cell count and percentage of macrophages between the two asthma groups and the control group (P>0.05). The percentages of neutrophils, eosinophils and epithelial cells in BALF were significantly higher in the two asthma groups than in the control group (P<0.05). The two asthma groups had significantly higher levels of IL-17 and TGF-β1 in serum and BALF than the control group (P<0.05), and the moderate or severe asthma group had significantly higher levels of IL-17 and TGF-β1 in serum and BALF than the mild asthma group (P<0.05). Levels of IL-17 and TGF-β1 in serum were significantly positively correlated with those in BALF (r=0.935 and 0.943, P<0.05 for both). In children with asthma, serum IL-17 level was significantly positively correlated with the percentage of neutrophils, eosinophils and epithelial cells in BALF (r=0.802, 0.799, and 0.674, P<0.05 for all), and a significant positive correlation was also seen between serum levels of IL-17 and TGF-β1 (r=0.878, P<0.05). CCONCLUSIONS: Levels of IL-17 and TGF-β1 in serum and BALF are elevated in children with asthma. IL-17 and TGF-β1 may be involved in the occurrence and development of asthma, and they play important roles in asthma attack and aggravation.

OBJECTIVE: To investigate the prevalence and incidence of asthma among children aged 0-14 years, with different living environments, economic levels, and sanitary conditions, in the urban and rural areas of Chengdu, China, and their influential factors. METHODS: Children aged 0-14 years who were selected from urban, suburban and rural areas of Chengdu, were included in the study. The subjects were selected from all children aged 0-14 years in schools, kindergartens and communities by random, cluster and non-proportional sampling. Parents were surveyed by questionnaire to find out suspected cases, which were then confirmed by inquiry and physical examination in the department of respiratory medicine. All the obtained data were analyzed using SPSS/PC statistical software. RESULTS: A total of 12082 children from the urban areas, 5677 from suburban areas and 5590 from the rural areas were included in the study. Of all the subjects, 551 (4.56%) had confirmed asthma, 150 (2.64%) had cough variant asthma (CVA), and 142 (2.54%) had suspected asthma. The prevalence rate of asthma was significantly higher in the urban areas than in the suburban and rural areas. The correct rate of diagnosis of asthma and CVA was highest in the urban areas, followed by the suburban and rural areas. Use of antibiotics and systemic corticosteroids was most common in the rural areas, followed by the suburban and urban areas, but this pattern was reversed for use of inhaled corticosteroids and leukotriene modifier. All the results in the three areas demonstrated that sex, age, age at which the first attack occurred, respiratory tract infection, inhalation/intake of allergens and genetic factors were significantly associated with asthmatic attack. CONCLUSIONS: Population density, living environment, medical and health resources and economic level are associated with the prevalence and treatment of asthma

OBJECTIVE: To investigate early serum lipid profiles in preterm infants and their relationship with neonatal respiratory distress syndrome (RDS). METHODS: Appropriate-for-gestational-age (AGA) preterm infants were grouped according to gestational age (GA) or birth weight (BW). AGA full-term infants were randomly selected as the control group. Venous blood samples were collected within 12 hours after birth for measurement of biochemical indices, including total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C) and triglyceride (TG). Blood lipid levels were compared between preterm infants with and without RDS in various groups. RESULTS: Plasma TG level rose as GA and BW increased. Plasma TG levels in the 28-30 week and 31-33 week GA groups were significantly lower than in the 34-36 week GA and control groups (P<0.01). Plasma TG levels in the ≤1499 g and 1500-2499 g BW groups were significantly lower than in the ≥2500 g BW and control groups (P<0.05), and the 1500-2499 g BW group had a significantly higher plasma TG level than the ≤1499 g BW group (P<0.01). There were no significant differences in plasma HDL-C, LDL-C and TC levels between all groups and between preterm infants with RDS and without RDS. In the 28-30 week GA group, the preterm infants with RDS had a significantly lower TG level than those without RDS (P<0.05); also, in the ≤1499 g BW group, preterm infants with RDS had a significantly lower TG level than those without RDS ( P<0.05). CONCLUSIONS: Blood lipid levels are related to GA and BW. Low TG level may be one of the causes of RDS in preterm infants with a gestational age of 28-30 weeks and a BW of ≤1499 g.

OBJECTIVE: To investigate the changes in plasma levels of thrombomodulin (TM) and D-dimer (DD) in children with different types of Mycoplasma pneumoniae pneumonia (MPP), and their role in the pathogenesis of MPP in children. METHODS: Fifty-two children with MMP were divided into lobar pneumonia (n=30) and interstitial pneumonia groups (n=22) and another 30 healthy children were selected as the control group. Plasma levels of TM and D-D were measured using enzyme-linked immunosorbent assay and latex-enhanced immunoturbidimetric assay, respectively. RESULTS: The lobar pneumonia, interstitial pneumonia and control groups had median plasma TM levels of 23.83, 15.56 and 8.78 μg/L respectively, with significant differences between the three groups (P<0.01). The lobar pneumonia and interstitial pneumonia groups had significantly higher plasma TM levels than the control group (P<0.01), and the lobar pneumonia group had a significantly higher plasma TM level than the interstitial pneumonia group (P<0.05). Median plasma D-D levels in the lobar pneumonia and interstitial pneumonia groups were significantly higher than the reference value (P<0.01). The lobar pneumonia group had a significantly higher plasma D-D level than the interstitial pneumonia group (0.35 μg/mL vs 0.13 μg/mL; P<0.01), and the percentage of patients with elevated plasma D-D levels was significantly higher in the lobar pneumonia group than in the interstitial pneumonia group (87％vs 59％; P<0.05). CONCLUSIONS: Children with MPP, especially those with lobar pneumonia, have increased plasma levels of TM and D-D. This suggests that damage to vascular endothelial cells and blood hypercoagulability may be involved in the pathogenesis of MPP.

OBJECTIVE: To investigate the risk factors and preventative measures for neonatal pneumothorax. METHODS: Retrospective analysis was performed on the clinical data of 2286 neonates who were hospitalized in the neonatal intensive care unit between October 2010 and November 2011, and a case-control study was conducted to analyze the risk factors and preventative measures for neonatal pneumothorax. RESULTS: The incidence of pneumothorax among the neonates was 1.57% (36/2286), and it was significantly higher in full-term infants than in preterm infants (23/1033 vs 13/1253, P=0.023). Logistic regression analysis indicated that cesarean section, neonatal respiratory distress syndrome (NRDS), wet lung, pneumonia and mechanical ventilation were the independent risk factors for neonatal pneumothorax (odds ratios=7.951, 6.090, 7.898, 6.272 and 4.389; P<0.05 for all). The higher the peak inspiratory pressure (PIP) during mechanical ventilation, the higher the incidence of neonatal pneumothorax (P<0.001). Pulmonary surfactant reduced the incidence of pneumothorax among neonates with NRDS (2.9% vs 10.1%; P=0.006). CONCLUSIONS: Neonatal pneumothorax occurs mostly in full-term infants. Cesarean section, NRDS, wet lung, pneumonia and mechanical ventilation are closely associated with neonatal pneumothorax. Strict management of indications for cesarean section, keeping PIP at a low level during mechanical ventilation, and use of pulmonary surfactant are helpful in preventing neonatal pneumothorax.

OBJECTIVE: To investigate the isolation, purification and ex vivo expansion of CD34⁺CD59⁺ cells from the bone marrow of children with paroxysmal nocturnal hemoglobinuria (PNH), to evaluate the capability of long-term hematopoietic reconstruction of the expanded CD34⁺CD59⁺ cells, and to provide a laboratory basis for novel treatment of PNH. METHODS: CD34⁺CD59⁺ cells were isolated from the bone marrow mononuclear cells of children with PNH using immunomagnetic beads and flow cytometer in sequence. The isolated cells were subjected to ex vivo expansion in the presence of different combinations of hematopoietic growth factors for two weeks. The colony-forming cells and long-term culture-initiating cells (LTC-ICs) were cultured and counted. RESULTS: The optimal combination of hematopoietic growth factors for ex vivo expansion was stem cell factor+interleukin (IL)-3+IL-6+FLT3 ligand+thrombopoietin+ery-thropoietin, and maximum expansion (30.4±6.7 folds) was seen on day 7 of days 4 to 14 of ex vivo expansion. After ex vivo expansion, CD34⁺CD59⁺ cells remained CD59-positive, retained strong capability of forming colony-forming units, and could still form LTC-ICs. There was no significant difference in capability of forming LTC-ICs between CD34⁺CD59⁺ cells before and after expansion. The expansion capability of CD34+CD59+ cells from children with PNH was significantly lower than that of CD34⁺ cells from normal controls (P<0.01). CONCLUSIONS: The CD34⁺CD59⁺ cells from children with PNH can be expanded in vitro. Post-expansion CD34⁺CD59⁺ cells retain capability of long-term hematopoietic reconstruction. CD34⁺CD59⁺ cells showed no trend towards PNH clone during culture. Ex vivo expansion of CD34⁺CD59⁺ cells from children with PNH might be practical in performing autologous transplantation clinically for these children.

OBJECTIVE: To detect the expression of surface molecule CD96 on stem cell (LSC) in children with acute leukemia, and to explore its clinical significance. METHODS: Bone marrow mononuclear cells were isolated in 69 children with newly diagnosed acute leukemia. CD34⁺CD38^-CD123⁺ LSCs were separated from these cells by flow cytometry (FCM) and then cultured, and CD96 expression on LSCs was detected by FCM. R-banding technique was used to analyze the karyotypes of the 69 children, and the data of their routine blood and immunological tests were collected. RESULTS: CD96 was mainly expressed in children with acute myelogenous leukemia, and expressed to a lesser extent in those with acute lymphoblastic leukemia (P<0.05). The median expression level of CD96 in Uyghur children was 23.4%, versus 21.2% in Han children (P>0.05). The majority of children with CD96^-positive children presented poor-prognosis karyotypes. Compared with CD96^-negative children, children with CD96^-positive children had a significantly lower complete remission rate (P<0.05) and significantly higher infection and relapse rates after chemotherapy (P<0.05).  CONCLUSIONS: Children with acute leukemia who have CD96^-positive LSCs have a poor prognosis. CD96 may be a new indicator of prognosis in children with acute leukemia.

OBCTIVE: To investigate the epidemiological characteristics of tic disorders (TD) among pupils in the Shunde Longjiang area, and their relationship to trace elements. METHODS: A cross-sectional study of 4062 children aged 6-12 years, who were selected from the Shunde Longjiang area by stratified cluster sampling to investigate the epidemiological characteristics of TD, was conducted, and blood concentrations of trace elements in children with TD were determined. Forty normal children were selected as controls. RESULTS: The overall prevalence rate of TD was 2.98%; the prevalence rates of transient tic disorder, chronic motor or vocal tic disorder and Tourette's syndrome were 3.62%, 2.39% and 1.21% respectively. Boys had a significantly higher prevalence rate of TD than girls (3.92% vs 1.96%; P<0.05). There were no significant differences in blood copper, manganese and magnesium levels between children with TD and normal children (P>0.05), however, children with TD had a significantly increased blood lead level and significantly decreased blood zinc and iron levels compared with the normal children (P<0.05). No significant differences in trace elements were found between children with different subtypes of TD (P>0.05). CONCLUSIONS: TD is common in children aged 6-12 years and more prevalent in boys than in girls. High blood lead level and zinc and iron deficiencies may be one of the causes of TD, and thus should be considered during therapy.

OBJECTIVE: To measure the expression of phosphatidylinositol 3-kinase (PI3K) and protein kinase B (PKB) in liver tissue among low-birth-weight newborn rats treated with L-arginine (L-Arg) in early life, and to investigate the effect of L-Arg on insulin resistance. METHODS: Eighteen pregnant rats were randomly divided into three groups: control, model and intervention (n=6 each). The control group was fed with normal protein feed (protein content=21%) during pregnancy to establish a normal-birth-weight newborn rat model, and the model and intervention groups were fed with low-protein feed (protein content=10%) during pregnancy to establish a low-birth-weight newborn rat model. Newborn rats from the three pregnant rat groups were also assigned to control, model and intervention groups. During 21 days of lactation, maternal rats in the control and model groups were fed with normal protein feed and normal drinking water, while maternal rats in the intervention group were fed with normal protein feed and drinking water rich in L-Arg (200 mg/kg·d). After ablactation, the three groups of newborn rats were fed with normal protein feed and normal drinking water. Liver tissue samples were collected from these newborn rats at 1, 3 and 8 weeks after birth. Protein expression of PI3K and PKB in liver tissue was measured by Western blot. RESULTS: At 1 week after birth, the newborn rats in the intervention group had significantly higher protein expression of PI3K than in the model group (P=0.045), but there was no significant difference when compared with the control group (P=0.503). At 8 weeks after birth, the newborn rats in the intervention group had significantly higher protein expression of PKB than the model group (P=0.039), but there was no significant difference when compared with the control group (P>0.05). CONCLUSIONS: A supplement of L-Arg in early life can boost protein synthesis, increase protein expression of PI3K and PKB in liver tissue, promote insulin signaling and reduce insulin resistance.

Dramatic advances in neonatal medicine over recent decades have resulted in decreased mortality and morbidity rates for extremely low birth weight infants. However, the survival of these infants is associated with short- and long-term morbidity, including severe intraventricular hemorrhage, periventricular leukomalacia, nosocomial infection and necrotizing enterocolitis, bronchopulmonary dysplasia, retinopathy of prematurity and adverse long-term neurodevelopmental sequelae. This article reviewed the latest advances in the medical care for extremely low birth weight infants including survival rate, ethical issues and short- and long-term morbidity, domestically and abroad.