OBJECTIVE: To explore whether the transcription factor NF-κB takes part in baicalin-induced differentiation of bone marrow stromal cells (MSCs) into neurons. METHODS: MSCs from adult rats were induced by baicalin in the serum-free medium for 6 hs. The un-treated cells, as the control group, were only induced in the serum-free medium without baicalin. The expression of neuronal specific markers was evaluated by indirect immunofluorescence cytochemistry staining. The activity of NF-κB was measured by the presence of the NF-κB subunit RelA ( p65) translocated into the nucleus in the same way. RESULTS: After the induction by baicalin, MSCs displayed neuronal morphologies, such as pyramidal cell bodies and extensive networks of processes, and the expression of neuron-specific markers was detectable 6 ds after the induction. Neuronal specific marker proteins did not express in the control group. Six days after the induction, the P65 positive rate in the cytoplasm of the control group decreased to (18.4 ± 3.0) % , while in the baicalin group, the P65 positive rate in the cytoplasm was (84.8 ± 3.0)%. CONCLUSIONS: Baicalin may inhibit the activation of NF-κB, which may act in the differentiation of MSCs into neurons. [Chin J Contemp Pediatr, 2003, 5(1): 1 - 4]

OBJECTIVE:To explore the NS gene structure and mutation of Chinese strains of human Parvovirus B19 (HPV B19). METHODS: NS genes of R19-XA17, XA18 and XA20 strains from three Chinese children with acute aplastic anemia were amplified by PCR, and then the amplified products were sequenced directly. RESULTS: Compared with the sequence of Au strain, four bases of NS genes of B19-XA17, XA18 and XA20 strains changed and their coding amino acids changed also. CONCLUSIONS: Genetic diversity exists in mucleotide sequences of NS gene of HPV B19 isolated from the serum of Chinese children. [Chin J Contemp Pediatr, 2003, 5(1): 5 - 7]

OBJECTIVE: ATRA can restrain proliferation and promote differentiation in various tumor cells. The aim of the study is to investigate the differentiation characteristics of K562 induced by ATRA. METHODS: Morphology (Benzidine staining, Wright's staining, NSE staining and NBT recovery test) and flow cytometry were used to observe the differentiation characteristics of K562 after co-incubation with 1 μmol/L and 2.5 pmol/L ATRA for 1 d, 4 ds, and 5 ds. RESULTS: Co-incubated for 4 ds, 61.5% K562 cells in the 1 μmol/L ATRA group and 39% K562 cells in the 2.5 μmol/L ATRA group showed some evidence of myeloid maturation, but no evidence of erythroid or monocytoid maturation. Cb-incubated for 5 ds, the percentage of differentiated K562 cells was much higher than that in the control group. One day after induction by 1 μmol/L ATRA or 2.5 μmol/L ATRA, the expression of CD13 was 8.0% and 6.7%, respectively, which was higher than that in the control group (2.1%). Five days after induction by 1 μmol/L ATRA or 2.5 μmol/L ATRA, the expression of CD13 increased to 28.1 % and 37.8 % , respectively, while the expression of CD71 decreased to 1.2 % and 0.9 % respectively. The differences between the ATRA groups and the control group were significant ( P < 0.05). CD71 decreased from 9.7% and 10.8% in the 1 μmol/L and 2.5 μmol/L ATRA groups on day 1 to 1.2% and 0.9% on day 5, while the CD13 expression level increased from 8.0% and 6.7% to 28.1% and 37.8% , respectively. CONCLUSIONS: ATRA can induce K562 to differentiate into myeloid linage. [Chin J Contemp Pediatr, 2003, 5(1): 8-11]

OBJECTIVE: To explore the protective mechanism after hypoxic-ischemic and reperfusion damage of the brain. METHODS: Seven-day-old SD rats from seven broods (eight rats from each brood, n = 56) were randomly divided into the HIBD group and sham operation group. The HIBD model was established by temporarily occluding the right common carotid artery for 3 hours with a thread through an elastic tube, and then they were exposed to the gas mixture of 80 ml/L oxygen and 920 ml/L nitrogen for 1 h. After 3 hs, the common carotid artery was reperfused. The blood flow of the right common carotid artery was detected by the Color Doppler. The expressions of p-CREB and c-fos in the hippocampus at different reperfusion periods (3 hs, 6 hs, 24 hs, 48 hs, 72 hs and 7 days after reperfusion and 24 hs after sham operation) were detected by immunohistochemical methods. Thionin staining was used to observe the apoptosis of neurons. RESULTS: In the HIBD group, the expression of p-CREB in the right hippocampus peaked 3 hs and 24 hs after reperfusion, and then decreased to the level of the sham group on the seventh day. The expression of c-fos reached the peak 6 hs after reperfusion, and another peak appeared 48 hs after reperfusion. Seven days after reperfusion, the number of c-fos positive cells decreased, but they were still more than those in the sham operation group ( P <0.0l). Using Thionin staining, we found that the apoptosis of neurons in the CA1 region marked 24 hs after reperfusion. CONCLUSIONS: The persistent activation of CREB in the hippocampus regulates the expression of c-fos through signal transduction, and it is involved in the course of neurons' survival and repair during the period of post hypoxic-ischemia reperfusion. It is very important for the protection of pyramidal hippocampal neurons of the damaged side, especially of the sensitive CA1 region. [Chin J Contemp Pediatr, 2003, 5(1): 12 - 16]

OBJECTIVE: To investigate the relationship between behavioral problems and family environment in children with asthma so as to provide theoretical bases for psychological intervention in general treatment measures in children with asthma. METHODS: The Family Environment Scale Manual (Chinese Version) (FES-CA) and Conners Child Behavioral Scale were used to investigate both behavioral problems and family environment in 100 children aged from 3 to 12 years (including 50 children with asthma and 50 healthy children). The results were analyzed using multiple regression analysis. RESULTS: Behavioral problems were more prevalent in the asthmatic children than in the healthy children (36.0% VS 12.0% ); the differences were significant ( P < 0. 01); the family factors influencing the children's behavior with asthma were emotional expressiveness, conflict, cohesion and intellectual-cultural orientation. CONCLUSIONS: Child asthma is related to psychological family factors. So it is required to provide psychological and family intervention during medical treatments in children with asthma. [Chin J Contemp Pediatr, 2003, 5(1): 17- 19]

OBJECTIVE:To study the relationship between PPD reaction and serum ECP and IgE levels, and cytokines expression in children with acute bronchial asthma. METHODS: The PPD test was performed, serum levels of ECP and IgE were determined and the expressions of IFN-γ, IL-4 and IL-12 P40 mRNA in the peripheral blood were determined following PPD stimulation in 32 asthmatic children. Eight healthy children served as the controls. RESULTS: The number of PPD negative responders (n= 24) were significantly greater than that of PPD positive ones (n= 8). Of the 24 children with negative PPD, 16 (66.7%) had moderate or severe asthma attacks and only 2 cases (25.0%) in the 8 children with positive PPD (66.7% vs 25.0%, P < 0.05). The levels of ECP and IgE were higher in the PPD negative patients than those in the PPD positive patients ( P < 0.05). After PPD stimulation in the asthmatic patients there was no significant change of IL-12 mRNA and IFN-γ mRNA expressions, while IL-4 mRNA expression increased compared with the healthy children ( P < 0.05). CONCLUSIONS: There might be cellular immunity deficiency in PPD negtive patients. The immunoenhancement effect following PPD stimulation is suppressed in asthmatic patients.

OBJECTIVE: To study the changes of serum levels of IgE, T-cell subgroups and cytokines in children with bronchial asthma during the stage of attack and convalescence. METHODS: The levels of T-cell subgroups were determined by the mono-clone antibody indirect-immuofluorence method and the levels of IgE, IL-2, IL-4, IL-6, IL-8 and IFN-γ were detected using ELISA in 45 children with asthma in the stage of attack and convalescence. Twenty healthy children served as the controls. RESULTS: Compared with the controls, there were higher levels of CD3+ and CD4+/ T cells and the ratio of CD4+/CD8+ in the 45 children with asthma in the stage of attack and convalescence ( P<0.05,P<0.01, P < 0.01, respectively), whereas there was no difference in the CD8+ T cell level. The CD4+ T cell level and the ratio of CD4+ /CD8+ of patients were higher in the stage of attack than those in the stage of convalescence ( P <0. 05). The levels of IL-2 and IFN-γ in the asthmatic children in the stage of attack were lower than those of the controls ( P <0.01 or 0.05) and the levels of IL-4, IL-6, IL-8 and IgE were higher than those of the controls ( P <0.01 or 0.05). In the stage of convalescence, the levels of IL-2 and IFN-γ were lower and levels of IL-4, IL-8 and IgE were higher than those of the controls ( P < 0.05 or 0.01), while no difference was noted in the IL-6 level. CONCLUSIONS: Children with bronchial asthma in the stage of both attack and convalescence have an imrnunologic imbalance. A longer-time anti-alergic treatment administrated for childhood asthma is necessary. [Chin J Contemp Pediatr, 2003, 5(1): 23-26]

OBJECTIVE: To study the dynamic changes of serum neuro peptide Y (NPY) and calcitonin-gene related peptide (CGRP) in neonates with hypoxic-ischemic encephalopathy (HIE). METHODS: Forty-two neonates with HIE (Group A) and 30 normal neonates (controls, Gruop B) were enrolled in this research. Their serum contents of NPY and CGRP were measured with the radio-immuno-assay, and the cranial blood flow was recorded at the same time. RESULTS: The serum NPY content in Group A was significantly higher than that in Group B, especially on day 2 to day 3 following asphyxia [(168.3±10.9) ng/L vs (86.7±5.4) ng/L]( P <0.01). The serum CGRP content in Group A was lower than that in Group B, especially on day 2 to day 3 after asphyxia [(48.4± 3.7) ng/L vs (81.3±6.8) ng/L] ( P <0.01). CONCLUSIONS: NPY and CGRP might be important factors in the development of HIE. The dynamic measures of NPY and CGRP contents might be useful in determining the clinical management of HE. [Chin J Comtemp Pediatr, 2003, 5(1): 27 - 28]

OBJECTIVE: To study the relationship between the serum leptin level and growth & development in newborns. METHODS: The serum leptin level was examined by the radioimmunoassay (RIA) in 14 premature neonates and 66 term neonates. The term newborns were assigned into the large for gestational age (LAG) group (n= 18), the appropriate for gestational age (AGA) group (n = 32) and the small for gestational age (SGA) group (n = 16). The neonatal nutritional status was evaluated by Rohrer' s index. RESULTS: The leptin level in the preterm newborns was significantly lower than that in the term neonates [ ( 0. 66 ±1. 03) ng/ml vs (3. 59 ± 2.16 ) ng/ml ] ( P < 0.01). The leptin level in the AGA newborns [(3.06 ±0.96) ng/ml] was significantly lower than that in the LGA neonates [(4. 03 ±2.22) ng/ml], and was significantly higher than that in the SGA neonates [(1.13 ±1.98) ng/ml]. The serum leptin level was positively correlated with Rohrer' s index, neonatal weight and gestational age in the term neonates ( r =0.61, 0.68, 0.62, respectively; all P <0.01). CONCLUSIONS: The serum leptin level may be a valuable index to evaluate neonatal growth and nutrional status. [Chin J Contemp Pediatr, 2003, 5(1): 29-30]

OBJECTIVE: To study the complications of the respiratory distress syndrome (RDS) following pulmonary surfactant (PS) replacement therapy in neonates. METHODS: Ninety-eight newboms with RDS were assigned into the PS treatment group and the control group. The former, besides the usual treatment for the control group, received PS replacement. The duration of mechanical ventilation and oxygen treatment, survival rate, length of hospitalization and incidence of complications, including ventilator associated pneumonia, patent ductus arteriosus, lung hemorrhage, air leak, intracranial hemorrhage, bronchopulmonary dysplasia (BPD) and apnea were compared between the two groups. RESULTS: There were significant differences in the ventilation time [(7.0±5.4) days vs (9.5±6.2) days, P < 0.05) ], duration of the oxygen period [(10.0 ±6.4) days vs (13.2 ±8.1), P<0.05)] and survival rate [87.0% vs 69.2%, P <0.05)] in the PS treatment group compared with the control group. Significant differences were noted in the incidence of complications between the two groups; the PS treatment group had lower incidences of air leak and ventilator associated pneumonia [(15.2% vs 32. 7 % , 44.2 % vs 23. 9 % , respectively] (both P < 0.05). There were higher rates of cases without BPD or/and intracranial hemorrhage in the survivals of the PS treatment group compared with the central group [(75.0% vs92.5%, 77.8% vs 95.0%, 58.3% vs 80.0%, respectively] (all P <0.05). CONCLUSIONS: Mechnical ventilation days and the length of the oxygen treatment period could be reduced and the survival rate could be increased by PS replacement therapy in newboms with RDS. PS replacement therapy can decrease the incidence of complications, and decrease brain and pulmonary injuries and improve the quality of life of premature newboms.

OBJECTIVE: To study the effect of nitric oxide (NO) inhalation on platelet aggregation in neonates with persistent pulmonary hypertension. METHODS: The platelet aggregartion rate with the induction of epinephrine, collagen and adenosine diphosphate (ADP) was assayed by turbidimetry 6 hours after NO inhalation in 11 neonates with persistent pulmonary hypertension (NO inhalation group). Twelve neonates with this disorder receiving oxgen inhalation served as the controls. RESULTS: The platelet aggregation rate with the induction of epinephrine, collagen and ADP was significantly inhibited in the NO inhalation group compared with the controls: (0.39 ±0.11)% vs (0.48±0.10)%, (0.41±0.19)% vs (0.69 ± 0.22)%, (0.32±0.12)% vs (0.50 ± 0.16)%, respectively ( P <0.05 or 0.01). CONCLUSIONS: NO inhalation may restrain platelet aggregation and increase hemorrhage risk.

OBJECTIVE: To investigate the distribution of vitamin D receptor (VDR) gene polymorphism in Hui and Han ethnic children in Lanzhou region and to study the difference between children of the two different ethnic groups. METHODS: VDR genotypes were assayed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) in 81 healthy Hui ethnic children and in 169 healthy Han ethnic children. RESULTS: Frequencies of bb, Bb and BB genotype were 70. 4% , 27. 2% and 2.5% respectively in the 81 Hui ethnic children and they were 91.1 % , 7.1% and 1.8% respectively in the 169 Han ethnic children. CONCLUSIONS: There is a significant difference in the frequency distribution of VDR genotype between Hui and Han ethnic children. [Chin J Contemp Pediatr, 2003, 5(1): 37-38]