Association between development of hypertension and nutrition in school-age children in Fengdu County of Chongqing, China / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To investigate the association between the development of hypertension and nutrition in school-age children in Fengdu County of Chongqing, China.</p><p><b>METHODS</b>A total of 8 033 children from 2 public primary schools in Fengdu County of Chongqing, whose registered residence was in the subdistricts where the two schools were located, were selected as study subjects using cluster random sampling. Body height, body weight, and blood pressure were measured, and the semi-quantitative food frequency questionnaire was used for dietary survey. The association between body mass index (BMI), dietary nutrients, and the development of hypertension in children was analyzed.</p><p><b>RESULTS</b>A total of 7 538 children were enrolled for analysis. The detection rates of obesity, overweight, and hypertension were 9.11%, 12.27%, and 11.83% respectively. In children with obesity and overweight, the detection rate of hypertension was 33.62% and 17.84% respectively, 4.02 and 2.13 times that in normal children. The multivariate logistic stepwise regression analysis revealed that increased intake of calcium and sodium increased the risk of hypertension (OR=1.003 and 1.002 respectively), while the increased iron intake and calcium intake per unit body weight reduced the risk of hypertension (OR=0.979 and 0.926 respectively).</p><p><b>CONCLUSIONS</b>The prevalence of hypertension and obesity in school-age children in Fengdu County of Chongqing is high. BMI and dietary nutrients are closely associated with the development of hypertension in children. Active control of body weight, adjustment of dietary structure, and limitation of sodium intake should be adopted to reduce the development of hypertension in school-age children.</p>

Impact of antioxidant vitamins and heavy metal levels at birth on neurodevelopment of children assessed at two years of age / 中华儿科杂志

<p><b>OBJECTIVE</b>Epidemiologic study on the perinatal interaction of antioxidant vitamins and heavy metals on offspring's intellectual development is extremely limited. The aim of this prospective cohort study was to investigate the status of maternal and cord blood antioxidant vitamins (Vitamin A, E and C) and heavy metals (lead, cadmium and mercury) at delivery and correlations between these antioxidant vitamins or metals and neurodevelopment of early childhood, and to explore the protective effect of antioxidant vitamins against the injure of heavy metals to intellectual development in children in Tongliang, Chongqing, China.</p><p><b>METHOD</b>A total of 150 pairs of mothers-neonates were recruited. Serum concentrations of vitamin(V) A, vitamin E, vitamin C, lead, cadmium and mercury in maternal and cord blood after delivery were determined and intellectual development was evaluated by Gesell Development Schedule (GDS) at two years of age.</p><p><b>RESULT</b>A total of 111 pairs of maternal-neonatal subjects with completed data were included into statistical analysis. After adjusting for potential confounders, cord blood mercury level was found negatively associated with all the development quotients (DQs) (β = -0.486, β = -0.716, β = -0.846, β = -0.935, β = -0.702, P < 0.05). Cord VE level was positively correlated with motor, adaptation, language and average DQ (β = 0.475, β = 0.458, β = 0.403, β = 0.395, P < 0.05). When antioxidant vitamins and heavy metals levels were all included into the multiple regression model, cord vitamin E level was statistically positively related with motor, adaptation and average DQs (β = 0.449, β = 0.412, β = 0.349, P < 0.05). While cord blood mercury level was negatively correlated with adaptation, language, social and average DQ (β = -0.397, β = -0.727, β = -0.935, β = -0.628, P < 0.05), the relationship between cord mercury level and motor DQ was not statistically significant (P = 0.0890). The motor, adaptation, language and average DQs in high cord VE group were higher than those in low VE group (t = 2.93, t = 2.06, t = 2.13, t = 2.27, P < 0.05). Social DQ in high cord lead group was significantly lower than that in low lead group (χ(2) = 5.56, P = 0.015). Cord VC level in high cadmium group was significantly lower than that in low cadmium group (χ(2) = 7.62, P = 0.006). VA placental transport ratio in high mercury group was significantly lower than those in low mercury group (χ(2) = 8.02, P = 0.005).</p><p><b>CONCLUSION</b>Our data suggested that there may be certain interaction between antioxidant vitamin A, E, C and heavy metals lead, cadmium, mercury. Antioxidant vitamins at delivery may have protective effect on the early neurodevelopment via interaction with the heavy metals.</p>

Effects of vitamin A, vitamin A plus iron and multiple micronutrient-fortified seasoning powder on iron metabolic homeostasis / 中华儿科杂志

<p><b>OBJECTIVE</b>To evaluate the effect of vitamin A, vitamin A plus iron and "7 + 1" multiple micronutrient-fortified seasoning powder on iron metabolic homeostasis in preschool children.</p><p><b>METHODS</b>This was a randomized, controlled and blinded interventional field trial. A total of 226 2 - 7 years old preschool children were recruited from three nurseries in the area, and they were randomly assigned into three different fortified diet groups for 6 months. The subjects in Group I were fortified with vitamin A; those in Group II and III were fortified with vitamin A plus iron and vitamin A plus iron, thiamine, riboflavin, folic acid, niacinamide, zinc and calcium (7 + 1), respectively. The concentration of serum vitamin A was measured by high-performance liquid chromatography (HPLC), serum ferritin (SF) was measured by enzyme-linked immunosorbent assay (ELISA), soluble transferrin receptor (sTfR) was measured by microparticle-enhanced, and hemoglobin (HB) by hemiglobincyanide, the sTfR-SF index (TFR-F index) and total body iron content were computed respectively before and after intervention. Simultaneously, children's demographic data, socio-economic status and eating habits, etc. were investigated by questionnaires.</p><p><b>RESULTS</b>A total of 226 preschool children were included in the study with age ranged from 2 to 7 years with average age (4.0 ± 0.85) (means ± standard deviation). The prevalence of anemia, deficient iron storage, vitamin A deficiency (VAD) and suspect sub-clinical vitamin A deficiency (SSVAD) were 23.5%, 15.0%, 6.3% and 25.9%, respectively. The levels of SF and sTfR significantly decreased after intervention in all groups (χ(2) = 8.3298, χ(2) = 16.1471, χ(2) = 15.1371, χ(2) = 15.1171, χ(2) = 5.2617, χ(2) = 4.8844, P < 0.05) especially in group II and group III for SF (χ(2) = 16.1471, χ(2) = 15.1371, P < 0.05) and group I for sTfR (χ(2) = 15.1171, P < 0.05). No marked change of TFR-F index and total body iron contents was observed in group I (t = 0.1817, t = 1.7736, P > 0.05), while TFR-F index decreased and total body iron contents increased in group II and group III (t = 5.3561, t = 6.5979, t = 11.1663, t = 8.7306, P < 0.05) after intervention.</p><p><b>CONCLUSION</b>Vitamin A intervention has significant effect on iron storage and mobilization but seldom effect on iron absorption in small intestine. The combination of vitamin A and other micronutrients might be a better intervention for the improvement of iron deficiency for preschool-children.</p>

Primary culture of rat hippocampal neurons and detection of the neuronal excitability / 南方医科大学学报

<p><b>OBJECTIVE</b>To improve the efficiency of primary culture of hippocampal neurons and obtain highly purified neurons with good in vitro growth and minimal risk of contamination.</p><p><b>METHODS</b>The hippocampal neurons of neonatal Wistar rats were isolated and the single cell suspension was prepared by mechanical trituration and sedimentation in stead of trypsin digestion and filteration. Twenty-four hours after the cell plating, the culture medium was removed and replaced by serum-free DMEM/F12 with B27 supplementation. Half of the culture medium was changed 2-3 times every week. The morphological changes of the neurons were observed under inverted phase-contrast microscope. Immunofluorescence staining for NSE was performed to identify the neurons, and the purity of neurons was calculated. The hippocampal neurons were stained with calcium-sensitive fluorescent dye to monitor the effect of KCl on neuronal excitability by a calcium imaging system.</p><p><b>RESULTS AND CONCLUSION</b>This simplified method is time-saving and cost-effective for primary culture of hippocampal neurons with reduced risk of contamination, and the neurons obtained showed high uniformity, purity and long-term viability.</p>

Effects of bone marrow mesenchymal stem cells on learning and memory functional recovery in neonatal rats with hypoxic-ischemic brain damage / 中华儿科杂志

<p><b>OBJECTIVE</b>Neonatal hypoxic-ischemic brain damage (HIBD) causes acute death and chronic nervous system sequelae in newborn infants and children. Whereas there have been no specific treatment towards it up to now. Studies have shown that bone marrow mesenchymal stem cells (MSCs) have the therapeutic potential in many nervous system diseases and the authors previously found that retinoid acid (RA), which plays an important role in brain development, could enhance the neural differentiation of rat MSCs (rMSCs) in vitro. This study aimed to examine effects of rMSCs and RA-preinduced rMSC on learning and memory functional recovery after HIBD in neonatal rats in order to explore a new treatment strategy for clinical application, and explore the mechanism of action of rMSCs.</p><p><b>METHODS</b>Rat MSCs were isolated and purified from the whole bone marrow of juvenile Wistar rats by removing the non-adherent cells in primary and passage cultures. Neonatal hypoxic-ischemic brain damage rat models were built according to the methods described by Rice: the right carotid artery of 7-day-postnatal Wistar rats was ligated under anesthesia, and then the rats were exposed to 8% - 9% O2 in a container. At 5 days after hypoxia-ischemia, the HIBD neonatal rats were randomly divided into 3 groups and respectively transplanted with saline, BrdU marked rMSCs (1 - 2 x 10(5)) or RA-preinduced rMSCs (1 - 2 x 10(5)) into their lateral cerebral ventricle. Immunohistochemistry for nestin, neuron-specific enolase (NSE), neurofilament protein-heavy chain (NF-H) and glial fibrillary acidic protein (GFAP) were used to identify cells derived from rMSCs at 14 days and 42 days after transplantation. Shuttle box test was performed to evaluate the condition of learning and memory functional recovery when animals were 7 weeks old. Neurotrophin and receptors cDNA microarray were also employed at 14 days after transplantation to investigate the underlying action mechanisms of rMSCs treatment. Real-time PCR was used to confirm some of the remarkably changed genes.</p><p><b>RESULTS</b>(1) The neonatal rat model of HIBD was successfully established. (2) Immunohistochemistry showed rMSCs-derived cells survived, migrated into the hypoxic-ischemic brain tissue and a few of them expressed protein characteristic of neurons and astrocytes (NF-H and GFAP) in RA-preinduced group 14 days and 42 days after transplantation, while no positive expression of nestin and NSE were detected. (3) The shuttle box test showed that the average learning times in rats transplanted with saline, rMSC and RA-preinduced rMSCs were (94.10 +/- 38.18), (74.60 +/- 29.21) and (47.90 +/- 21.13), respectively. The difference between the former two was not significant (P > 0.05), while the latter one exhibited significant improvement (P < 0.05). (4) The cDNA microarray analysis showed that compared with normal control group, IL-6, Fas and BDNF genes of the saline control group significantly up-regulated (the ratios of the three genes were 11.4, 2.4 and 6.6 respectively). Compared with saline group, the three genes in rMSC group were down-regulated (the ratios were all 0.1), while the levels of IL-6 and Fas genes (the ratios were 0.3 and 0.4 respectively) in RA-preinduced rMSCs group were higher than rMSCs group after down-regulating, but the level of BDNF remained at the saline group level. Real-time PCR analysis suggested that the results of IL-6 and Fas genes were at equal level with microarray results on the whole, while the level of BDNF gene in RA-preinduced rMSC group was significantly down-regulated (with ratio of 0.34), but higher than rMSCs group (the ratio was 0.25) as well.</p><p><b>CONCLUSION</b>Transplantation of rMSC and RA-preinduced rMSCs into lateral cerebral ventricle can improve learning and memory functional recovery after HIBD in neonatal rats, especially RA-preinduced rMSCs. Regulating the levels of IL-6, Fas and BDNF in the brain to maintain at reasonable levels may be the mechanism.</p>

Effects of early intervention on learning and memory in young rats of marginal vitamin A deficiency and it's mechanism / 中华儿科杂志

<p><b>OBJECTIVE</b>In recent years, some experiments on vitamin A-deprived animals reveal a progressive and ultimately profound impairment of hippocampal CA1 area's long-term potentiation and these losses are fully reversible by dietary vitamin A replenishment in vivo. Our previous study revealed that marginal vitamin A deficiency (MVAD) beginning from embryonic period impairs learning, memory and long-term potentiation (LTP) in young rats. But the losses might not be reversible if the vitamin A supplementation is late, especially when the critical period of hippocampus development is missed. The present study aimed to observe the recovery of learning and memory in vitamin A marginally deficient young rats after early intervention with vitamin A supplementation and begin to study the mechanism.</p><p><b>METHODS</b>Rats were divided into control, MVAD, vitamin A intervention 1 (VAI1) and VAI2 groups in this study. In control group (10 young rats) the dams and pups were fed with normal diet (VA 6500 U/kg). In MVAD group (19 young rats) the dams and pups were fed with MVAD diet (VA 400 U/kg). In VAI1 group (10 young rats) the dams were fed with MVAD diet till day 14 of pregnancy, then were fed with normal diet and the pups were fed with normal diet. In VAI2 group (13 young rats) the dams were fed with MVAD diet till delivery, then were fed with normal diet and the pups were fed with normal diet too. All the young rats were killed at the age of 7 weeks. During the last week of the experiment, the shuttle box active avoidance reaction tests were carried out. At week 7, the hippocampal CA1 LTP was detected by electrophysiological technique. The expression of RAR-alpha, RAR-beta, RXR-beta, RXR-gamma, RC3 and tTG mRNA was detected by using semi-quantified RT-PCR in hippocampus.</p><p><b>RESULTS</b>(1) The times to reach the learning standard in MVAD group (45.6 +/- 12.1) were more than those in control group (17.1 +/- 4.4) (P < 0.01), in both VAI1 group (20.8 +/- 3.1) and VAI2 group (22.1 +/- 4.0) were more than those in group MVAD (P < 0.01), and there were no significant differences among groups VAI1, VAI2 and control (P > 0.05) in active avoidance reaction tests. (2) The changes of field excitatory postsynaptic potentials (fEPSP) slope for MVAD group [(22.9 +/- 9.4)%] and VAI2 group [(39.1 +/- 4.33)%] were less than that of control group [(57.5 +/- 27.3)%], respectively (P < 0.05). No significant difference was found between VAI1 and control group (P > 0.05). (3) The expression of RAR-beta and RXR-beta mRNA decreased by 48.72% and 37.84% respectively (P < 0.05) compared with control, but the expression of RAR-beta mRNA in group VAI1 was higher than that in group MVAD (P = 0.065). The expression of RC3 mRNA in MVAD group was lower than that in control (P = 0.061) and RAR-alpha mRNA in MVAD group was higher than that in control (P = 0.061). The expression of RXR-gamma and tTG mRNA had no significant difference among different groups as determined with semi-quantified RT-PCR in hippocampus.</p><p><b>CONCLUSION</b>Early vitamin A intervention may make the impaired learning and memory behavior due to marginal vitamin A deficiency recover to the normal level in young rats, but lip losses in group VAI2 might not be reversible. Vitamin A may modulate the expression of RC3 mRNA by affecting RAR-alpha, RAR-beta and RXR-beta to influence the LTP, learning and memory.</p>

Effects of marginal vitamin A deficiency and intervention on learning and memory in young rats / 中华儿科杂志

<p><b>OBJECTIVE</b>Previous studies have demonstrated that vitamin A and its active derivatives function as essential competence factors for long-term synaptic plasticity within the adult brain. But little is known if marginal vitamin A deficiency (MVAD) beginning from embryonic period affects the brain development and the ability of learning and memory in young rats. The aim of this study was to identify the effects of MVAD and vitamin A intervention (VAI) on learning, memory and the hippocampal CA1 long-term potentiation (LTP) in young rats.</p><p><b>METHODS</b>Rats were divided into control, MVAD and VAI groups in this study. In control group (10 young rats) the dams and pups were fed with normal diet (VA 6500 IU/kg). In MVAD group (19 young rats) the dams and pups were fed with MVAD diet (VA 400 IU/kg). In VAI group (9 young rats) the dams were fed with MVAD diet and the pups were fed with normal diet from postnatal week 4. All the young rats were killed at the age of 7 weeks. During the last week of the experiment, the shuttle box active avoidance reaction tests were carried out. At week 7, the hippocampal CA1 LTP was detected by electrophysiological technique and relative intensity of fluorescence in cells in hippocampal slices was measured by confocal laser scanning microscopy labeled by fluo-3.</p><p><b>RESULTS</b>(1) The times to reach the learning standard in both VAI group (28.8 +/- 4.1) and MVAD group (45.6 +/- 12.1) were more than control group (17.1 +/- 4.4) (P < 0.01), and that of MVAD group was more than VAI group (P < 0.05) in active avoidance reaction tests. (2) The changes of field excitatory postsynaptic potentials (fEPSP) slope for MVAD group (22.9% +/- 9.4%) and VAI group (29.5% +/- 13.7%) were less than that of control group (57.5% +/- 27.3%), respectively (P < 0.01). No significant difference was found between VAI and MVAD groups (P > 0.05). (3) No significant differences of relative intensity of fluorescence in cells were found among the three groups before the tetanus stimulation. However, the significantly low relative intensity of fluorescence in cells was seen in MVAD (65.1 +/- 17.0) and VAI (85.8 +/- 17.1) groups compared with control group (113.6 +/- 20.5) after the tetanus stimulation (P < 0.01), and that of VAI group was higher than that of MVAD group (P < 0.05).</p><p><b>CONCLUSION</b>MVAD beginning from embryonic period impairs learning, memory and LTP in young rats. But the losses might not be reversible if the vitamin A supplementation is late especially missing the critical period of hippocampus development. According to the experimental data, it is speculated that vitamin A may modulate the influx of calcium ion to influence the LTP and lead to the change of learning and memory.</p>