OBJECTIVE: To investigate the biologic features of childhood acute leukemia in the northern region of China through a small cohort study in a single center. METHODS: The medical records of 688 children with acute leukemia (age ≤15 years) who were initially diagnosed at Blood Disease Hospital of Chinese Academy of Medical Sciences from October 2003 to June 2006 were retrospectively studied. RESULTS: Four hundred children were diagnosed as acute lymphoblastic leukemia (ALL), with a peak incidence at ages of 1-4 years. Two hundred and eighteen children were classified into B-cell ALL, and 34 into T-cell ALL. In the 154 patients with cytogenetic data, high hyperdiploidy was presented in 13.0% of patients, low hyperdiploidy in 3.9%, pseudodiploidy in 5.2%, and hypodiploidy in 5.8%. E2A-PBX1 fusion gene was expressed in 3.9% of children with B-cell ALL. Two hundred and twenty-two children were diagnosed as acute myeloid leukemia (AML), with a peak incidence at ages of 10-15 years. AML-M2 was the most common subtype. Acute hybrid leukemia (AHL) was confirmed in 24 children (4.2%), with a median age of 9 years. Seventy-four percent of the children with (AHL) had mainly CD13 and CD33 expression in myeloid antigen integral. CONCLUSIONS: There are differences in the biologic features of childhood acute leukemia between the northern region of China and other regions and races, which suggests that there might be differences in the pathogenesis of childhood acute leukemia in different environmental exposures.［Chin J Contemp Pediatr, 2009, 11 (10):793-796］

OBJECTIVE: To study the changes and significance of Toll-like receptor-2 (TLR2) and Toll-like receptor-4 (TLR4) on platelets, CD86 on lymphocytes and concentrations of IL-2, IFN-γ, IL-4 and IL-10 in serum in children with idiopathic thrombocytopenic purpura (ITP). METHODS: Peripheral blood samples were collected from 24 children with acute idiopathic thrombocytopenic purpura (AITP), 21 children with chronic idiopathic thrombocytopenic purpura (CITP) and 20 normal children (control group). Expression of TLR2 and TLR4 on platelets and CD86 on lymphocytes were detected by flow cytometry. Serum concentrations of IL-2, IL-4, IL-10 and IFN-γ were measured using ABC-ELISA. RESULTS: The expression of CD41+TLR2+ and CD61+TLR4+ in the AITP and the CITP groups were significantly lower than those in the control group (P<0.01). The AITP group had lower expression of CD41+TLR2+ and CD61+TLR4+ than the CITP group (P<0.01). The expression of CD86+ in the AITP and the CITP groups was significantly higher than that in the control group (P<0.01). The serum concentrations of IL-2, IL-4, IL-10 and IFN-γ in the AITP and the CITP groups were significantly higher than those in the control group (P<0.05). There was a positive correlation between CD41+TLR2+ and CD61+TLR4+ expression. CD41+TLR2+ and CD61+TLR4+ expression were negatively correlated with CD86+ expression and serum concentrations of IL-2, IL-4 and IL-10. CONCLUSIONS: The detections of TLR2 and TLR4 on platelets, CD86 on lymphocytes and serum concentrations of IL-2, IFN-γ, IL-4 and IL-10 are of great value in understanding the pathogenesis and predicting types of ITP in children.［Chin J Contemp Pediatr, 2009, 11 (10):797-801］

OBJECTIVE: To study the changes of serum leptin (LEP) and vascular endothelial growth factor (VEGF) in children with congenital heart disease(CHD) and their roles in CHD. METHODS: Forty-eight children with acyanotic CHD (ACHD group), 20 age-matched children with cyanotic CHD (CCHD group) and 20 healthy children (control group) were enrolled. The ACHD group was subdivided into two groups with (n=20) or without concurrent heart failure (n=28). Serum LEP, VEGF, total protein and albumin levels and body mass index (BMI) were measured. RESULTS: Serum total protein and albumin levels were not apparently different in all CHD children from healthy controls, but there was a significant difference in the BMI between them (P<0.01). Serum LEP and VEGF levels and the ratio of LEP/BMI in all CHD children were significantly higher than those in healthy controls (P<0.01). Compared with the ACHD group without heart failure, the serum LEP and VEGF levels and the ratio of LEP/BMI in the CCHD and the ACHD with heart failure groups increased significantly (P<0.01). In the ACHD group, serum LEP level was positively correlated with BMI (P<0.01). In the CCHD group, there were positive correlations between serum LEP level and serum VEGF level (P<0.01) and between hemoglobin concentration and serum VEGF level (P<0.01). Arterial oxygen saturation was negatively correlated with serum VEGF (P<0.01) and LEP levels (P<0.01) in the CCHD group. CONCLUSIONS: Both VEGF and LEP play roles in the pathophisiological process of CHD. VEGF and LEP are associated with the development of heart failure in children with ACHD. [Chin J Contemp Pediatr, 2009, 11 (10):802-805]

OBJECTIVE: To study the feasibility of umbilical cord brain natriuretic peptide (BNP) level measurement for the evaluation of perinatal cardiac function in fetuses from pregnant women with abnormal blood glucose levels and the influence of abnormal blood glucose on fetal cardiac function. METHODS: Twenty-four mothers with gestational diabetes mellitus (n=18) or gestational impaired glucose tolerance (n=6) (diabetic group) were classified into two subgroups according to blood glucose level before delivery: good (n=17) and poor (n=7) glucose control. They underwent fetal echocardiography in their late pregnant periods and fetal cardiac sizes and function were measured. Twenty-five normal pregnant mothers served as the control group. Umbilical cord blood BNP concentrations were measured at delivery. RESULTS: The umbilical cord blood BNP concentrations in the diabetic group were significantly higher than in the control group(114.0±39.0 pg/mL vs 80.6±13.7 pg/mL; P<0.01). The poor glucose control subgroup demonstrated higher umbilical cord blood BNP concentrations than the good glucose control subgroup (142.1±44.1 pg/mL vs 102.4±31.2 pg/mL; P<0.01). No difference was found between the gestational diabetes mellitus and the impaired glucose tolerance groups. The BNP concentration was positively correlated to the thicknesses of fetal left ventricular walls and the peak velocities of mitral A wave (r＝0.715, 0.491 respectively, P<0.05), and negatively correlated to the mitral E/A ratio (r＝-0.507, P<0.05). CONCLUSIONS: The fetuses of pregnant women with abnormal blood glucose levels have an increased BNP level in umbilical cord blood. Umbilical cord BNP level is related to maternal blood glucose control and the changes in fetal cardiac function. It may reflex the latent impairments of fetal cardiac function. A good glucose control may decrease the impact of abnormal maternal blood glucose on fetal hearts. [Chin J Contemp Pediatr, 2009, 11 (10):805-808]

OBJECTIVE: To study the diagnosis and treatment of persistent hyperinsulinemic hypoglycemia of infancy. METHODS: The clinical data of 12 infants with persistent hyperinsulinemic hypoglycemia were retrospectively reviewed. RESULTS: Convulsion, cyanosis, lethargy, refusing milk sucking, irritability and sweating were common symptoms. The laboratory findings displayed persistent hypoglycemia and hyperinsulinism in all of the 12 infants. The glucagon test showed positive and no urine ketones were detected in all of the 12 infants. Seven infants were treated with oral diazoxide (5-15 mg/kg daily) and 4 infants showed effective to the therapy. One patient was given subtotal pancreatectomy and the blood glucose level was restored to normal after operation. Of the 12 infants, 6 presented psychomotor retardation in a follow-up of 2 months to 67 months, 3 had loss to follow-up and 3 were still in a follow-up. CONCLUSIONS: The measurement of blood glucose, blood insulin and urinary ketons is helpful in the diagnosis of persistent hyperinsulinemic hypoglycemia of infancy. Diazoxide therapy is effective in some of patients.［Chin J Contemp Pediatr, 2009, 11 (10):809-812］

OBJECTIVE: To evaluate the clinical value of serum hypersensitive C-reactive protein (hsCRP) test in early diagnosis of early-onset infection in premature infants. METHODS: Thirty-five premature infants with early-onset infection, 50 premature infants with non-infectious diseases and 40 healthy premature infants 3 hrs after birth were enrolled. Serum hsCRP levels were measured by particle enhanced immunoturbidimetric assay. Diagnostic test of hsCRP was performed. RESULTS: Serum hsCRP levels shown as medium and inter-quartile ranges (M, Q75-25) were 2.19 and 4.96 mg/L respectively in the infection group, 0.41 and 0.61 mg/L respectively in the non-infectious disease group, and 0.24 and 0.28 mg/L respectively in the healthy group. Serum hsCRP levels in the infection group were significantly higher than those in the non-infectious disease and the healthy groups. When serum hsCRP test was used for the diagnosis of early-onset infection, the area under the ROC curve was 0.84, 95% confidence interval was 0.76-0.93, the diagnostic sensitivity and specificity were 74% and 86% respectively, and the positive and negative predictive values were 37% and 97% respectively. ConclusionsSerum hsCRP test is valuable in early diagnosis of early-onset infection in premature infants, but it can not serve as an independent diagnostic marker.［Chin J Contemp Pediatr, 2009, 11 (10):813-816］

OBJECTIVE: Fragile X syndrome (FXS) may be identified by many methods, such as PCR assay and Southern blot. However, each method has its limits or shortcomings. This study explored the reliability of the rapid, convenient and inexpensive hair root fragile X mental retardation protein (FMRP ) assay in the identification of FXS. METHODS: FMRP in hair roots was determined by immunohistochemistry assay in 80 healthy children, in 40 children with mental retardation of unknown etiology and in 12 family members in one pedigree of FXS. FXS was confirmed by 7-deza-dGTP PCR. RESULTS: There was a high expression of FMRP in hair roots (≥80%) in healthy children. Two children were confirmed with FXS by 7-deza-dGTP PCR in 40 children with mental retardation of unknown etiology. FMRP expression was 10% and zero respectively in the two children. The other 38 children had FMRP expression of more than 80%. FMRP was not expressed in the two cases of FXS from the pedigree of FXS. CONCLUSIONS: Inexpensive, rapid and convenient hair root FMRP assay is reliable for the diagnosis of FXS and may be widely applied for screening and diagnosing FXS in children with mental retardation.［Chin J Contemp Pediatr, 2009, 11 (10):817-820］

OBJECTIVE: To study the association of tumor necrosis factor (TNF)-α-308G/A and interleukin (IL)-6-174G/C gene polymorphisms with the susceptibility of respiratory syncytial virus (RSV) bronchiolitis. METHODS: Polymerase chain reaction-restriction fragment length polymorphism ( PCR-RFLP) was used to identify the polymorphisms at position 308 of the TNF-α promoter and -174 of the IL-6 promoter in 150 children with RSV bronchiolitis and 120 healthy children (control group). RESULTS: The frequency of GG, GA and AA genotypes of TNF-α-308 was 68.0%, 28.0% and 4.0% respectively in the RSV group, while that was 80.8%, 19.2% and 0 respectively in the control group. There were significant differences in the genotype frequencies between the two groups (χ2=5.665, P<0.05). The frequency of G and A alleles in the RSV group was 82.0% and 18.0% respectively, while that was 90.4% and 9.6% respectively in the control group. The frequency of A allele in the RSV group was significantly higher than that in the control group (χ2=7.726, P<0.05). Compared to the children carrying G allele, the children with A allele demonstrated a 2.071-fold increased risk of RSV bronchiolitis (OR=2.071, P<0.05). Only GG genotype was detected at position -174 of IL-6 in both groups. CONCLUSIONS: TNF-α-308A is associated with the susceptibility of RSV bronchiolitis and it might be an important candidate gene for the development of RSV bronchiolits. IL-6-174G/C gene polymorphism is not found in children in Wenzhou area.［Chin J Contemp Pediatr, 2009, 11 (10):821-824］

OBJECTIVE: Nucleic acid amplification (PCR) fluorogenic quantitative assay is used for the diagnosis of respiratory syncytial virus (RSV) infection. This study was designed to explore the sensitivity of PCR fluorogenic quantitative assay for ascertaining respiratory RSV infection and RSV infection conditions by detecting the presence of RSV-RNA related sequences in children. METHODS: Bronchial and nasopharyngeal secretions specimens from 261 hospitalized children with respiratory tract infections from January 2007 to October 2008 were collected. Respiratory syncytial virus nucleic acid (RNA) in the specimens was measuredby PCR fluorogenic quantitative assay. Blood RSV-IgM was detected by enzyme linked immunosorbent assay (ELISA). The sensitivity for ascertaining respiratory RSV infection was compared between the two assays. RESULTS: The RSV-RNA positive rate ascertained by PCR fluorogenic quantitative assay (38.7%) was significantly higher than blood RSV-IgM positive rate (21.1%) (P<0.01). The RSV-RNA positive rate (43.6%) in children at ages of less than 6 months was significantly higher than that in children at ages of 1 to three years (32.1%) (P<0.01). The RSV-RNA positive rate in children with bronchiolitis (58.5%) was the highest, followed by bronchopneumonia (38.2%) and acute bronchitis (20.0%). CONCLUSIONS: The sensitivity of PCR fluorogenic quantitative assay for ascertaining respiratory RSV infection is higher. RSV is a major pathogen of lower respiratory tract infections in infants and young children. A higher rate of RSV infection is associated with a younger age. RSV infection is the most common in children with bronchiolitis.［Chin J Contemp Pediatr, 2009, 11 (10):825-828］

OBJECTIVE: This study determined the changes of CD4⁺CD25⁺ regulatory T cells, IL-10 and TGF-β1 levels in peripheral blood in children with asthma in order to explore immunologic mechanism of asthma attacks. METHODS: Seventy-four children with asthma attacks, twenty-eight children with stable asthma and twenty healthy children were enrolled. The percentage of CD4⁺CD25⁺ regulatory T cells in CD4⁺ T cells in peripheral blood was detected by flow cytometry. Serum levels of IL-10 and TGF-β1 were measured using enzyme linked immunosorbent assay (ELISA). RESULTS: The percentage of CD4⁺CD25⁺ regulatory T cells and IL-10 levels in peripheral blood in the asthma attacks group were significantly lower than those in the stable asthma and the control groups (P<0.01) .The stable asthma group showed a similar percentage of CD4⁺CD25⁺ regulatory T cells and IL-10 levels to the control group. Compared with the stable asthma and the control groups, serum TGF-β1 level in the asthma attacks group increased significantly (P<0.05). In the asthma attacks, the stable asthma, and the control groups, the percentage of CD4⁺CD25⁺ regulatory T cells in peripheral blood was not correlated to serum levels of IL-10 and TGF-β1. CONCLUSIONS: The percentage of CD4⁺CD25⁺ regulatory T cells in peripheral blood and serum IL-10 levels decrease and serum TGF-β1 levels increases in children with asthma attacks, which results in a decreased immunosuppressive effect. This might contribute to one of the immunologic mechanisms of asthma attacks.［Chin J Contemp Pediatr, 2009, 11 (10):829-832］

OBJECTIVE: To study the intelligence level and structure in school age children with fetal growth restriction (FGR). METHODS: The intelligence levels were tested by the Wechsler Children Scales of Intelligence (C-WISC) in 54 children with FGR and in 84 normal children. RESULTS: The full intelligence quotient (FIQ), verbal IQ (VIQ) and performance IQ (PIQ) in the FGR group were 105.9±10.3, 112.4±11.2 and 97.1±10.6 respectively, and they all were in a normal range. But the PIQ was significantly lower than that in the control group (104.8±10.5; P<0.001), and the picture arrangement and the decipher subtest scores were significantly lower than those in the control group (P<0.01). The scores of perception/organization and memory/attention factors in the FGR group were 99.8±11.1 and 116.3±14.4, respectively, which were inferior to those in the control group (104.6±11.5 and 113.4±14.5 respectively; P<0.05). CONCLUSIONS: The total intelligence level of children with FGR is normal, but there are imbalances in the intelligence structure and dysfunctions in performance ability related to right cerebral hemisphere. Performance trainings should be done from the infancy in children with FGR.［Chin J Contemp Pediatr, 2009, 11 (10):833-835］

OBJECTIVE: By establishing a model of straight-leg swaddle of newborn rats and observing the experimental animals′ hips morphologically and pathologically, this study explored the changes of gross appearance of the acetabulum and the maturity of cartilage cells in the different regions of acetabular cartilage complex. METHODS: The legs and hips were fixed by adhesive tape for 10 days in the position of hip extension and adduction in 31 newborn Wistar rats (experimental group). The other 31 newborn rats without legs and hips treatment were used as the control group. After 10 days raising in the same condition, all the rats were sacrificed. The gross appearance, histological observations and VEGF and type X collagen immunohistochemistry were used for examining the acetabulum changes. RESULTS: A straight-leg swaddle model of newborn rats was established successfully. In the experimental group the acetabulum became shallow and small and surrounded by more soft tissues. There were 49 dislocated hips (49/54) in the experimental group and 2 hips dislocated (2/60) in the control group (P<0.01). Fake acetabulum appeared in the experimental group. In the control group, the shape of the acetabulum was normol, and no fake acetabulum was found. The safranin O-fast green staining showed that the orange-red cartilage in the experimental group was wider than the control group. Immunohistochemistry observations showed VEGF and type X collagen immunoreactivities in the hypertrophic layer of the acetabular cartilage complex in the experimental group were lower than those in the control group. The percentages of VEGF positive and type X collagen positive cells in the iliac hypertrophic layer of the acetabular articular cartilage were significantly higher than those in the ischiadic ramus and the pubic branch in the experimental group. CONCLUSIONS: VEGF and type X collagen immunoreactivities in acetabular cartilage cells decrease in a straight-leg swaddle model of newborn rats. This suggests that this position might lead to dysmaturity of the acetabular cartilage cells and affect the development of the acetabulum.［Chin J Contemp Pediatr, 2009, 11 (10):836-840］

OBJECTIVE: To study the effects of ganglioside 1 (GM1) and nerve growth factor (NGF) on neural stem cells (NSCs) proliferation in vitro. METHODS: NSCs were isolated and cultured in vitro. NSCs were cultured in the medium containing epidermal growth factor (EGF) and basic fibroblast growth factor (bFGF) or without the two agents. Different concentrations of GM1 and NGF were added into the two different medium. MTT and cell ball counting methods were used to ascertain the proliferation of NSCs. Immunohistochemical technology was used to observe the effect of GM1 and NGF on the proliferation of NSCs. RESULTS: High concentrations of GM1 (100 ng/L and 200 ng/L) promoted significantly the proliferation of NSCs in the medium containing EGF and bFGF (P<0.05). In the differentiation medium containing serum but no EGF and bFGF, NSCs proliferation increased with increasing concentration of GM1; the proportion of neurons and gliacytes increased with increasing concentration of NGF. CONCLUSIONS: High concentration of GM1 can promote NSCs proliferation and NGF can promote NSCs differentiation.［Chin J Contemp Pediatr, 2009, 11 (10):841-845］

OBJECTIVE: To study the effect of a new obesity-related gene NYGGF4 on the insulin sensitivity and secretory function of adipocytes. METHODS: 3T3-L1 preadipocytes transfected with either an empty expression vector (pcDNA3.1; control group) or an NYGGF4 expression vector (NYGGF4-pcDNA3.1) were cultured in vitro and differentiated into the matured adipocytes with the standard insulin plus dexamethasone plus 3-isobutyl-methylxanthine (MDI) induction cocktail. 2-deoxy-D-［3H］ glucose uptake was determined by liquid scintillation counting. Western blot was performed to detect the protein content and translocation of glucose transporter 4 (GLUT4). The supernatant concentrations of TNF-α, IL-6, adiponectin and resistin were measured using ELISA. RESULTS: NYGGF4 over-expression in 3T3-L1 adipocytes reduced insulin-stimulated glucose uptake. NYGGF4 over-expression impaired insulin-stimulated GLUT4 translocation without affecting the total protein content of GLUT4. The concentrations of TNF-α, IL-6, adiponectin and resistin in the culture medium of 3T3-L1 transfected with NYGGF4 were not significantly different from those in the control group. CONCLUSIONS: NYGGF4 over-expression impairs the insulin sensitivity of 3T3-L1 adipocytes through decreasing GLUT4 translocation and had no effects on the secretory function of adipocytes.［Chin J Contemp Pediatr, 2009, 11 (10):846-849］

OBJECTIVE: To study the roles of platelet (PLT) and its regulating factors, megakaryocyte, thrombopoietin (TPO) and transforming growth factor β1 (TGF-β1), in immune vasculitis in young rabbits. METHODS: An experimental model of Kawasaki disease (KD) of weanling rabbits was reproduced by bovine serum. PLT count, total number and differentiating count of megakaryocyte, and serum TPO and TGF-β1 levels were measured 0, 4, 8, 12, 16, 20, 24 and 28 days after KD induction. Pathological analysis of coronary artery, liver, spleen, kidney and brain was performed 17 and 28 days after KD induction. RESULTS: In the KD group, PLT count, the total number of megakaryocyte, and the middle board megakaryocyte percentage increased 12, 16, 20, 24 and 28 days; serum TPO level increased 8, 12, 16, 20, 24 and 28 days; serum TGF-β1 level increased 16, 20, 24 and 28 days after KD induction compared with those in the normal control group (P<0.05). The pathological examinations of coronary artery, liver, spleen, kidney and brain showed severe inflammatory injuries of tiny arteries and small/medium-sized arteries 17 and 28 days after KD induction, respectively in the KD group. The aortas were showed as mild inflammatory injuries. CONCLUSIONS: PLT, megakaryocyte, TPO and TGF-β1 participate in the pathogenesis of KD, and they may play an important role in the injuries of immune vasculitis. This suggests that they may serve as markers for the assessment of severity in KD.［Chin J Contemp Pediatr, 2009, 11 (10):850-853］