ABSTRACT
Objective@#To evaluate the association of long-term ambient fine particulate matters (PM2.5) exposure with elevated blood pressure in children.@*Methods@#From April 2012 to June 2013, we used cluster randomized sampling method to investigate 9 354 children aged 5-17 years old from 68 primary and middle schools in the seven Northeastern Cities (Shenyang, Dalian, Fushun, Anshan, Benxi, Liaoyang and Dandong) in Liaoning Province, and measured their blood pressure (BP). A spatial statistical model nested by aerosol optical depth (AOD) was used to inverse PM2.5 concentrations. Generalized additive model was used to quantify the association between PM2.5 exposure and blood pressure in children. To examine the associations, two-level regression model was used to evaluate individual characteristics′ modifying effect on the health influence of PM2.5.@*Results@#The prevalence of hypertension in children was 13.78% (1 289/9 354). The results showed that there was an associations between hypertension and pollutants, and the multivariable regression analysis indicated that the increase in mean systolic blood pressure (SBP), diastolic blood pressure (DBP), and the OR of hypertension associated with a 10 μg/m3 increase for PM2.5 were 3.12 (95%CI: 2.71-3.54) mmHg (1 mmHg=0.133 kPa), 1.45 (95%CI:1.12-1.78) mmHg, and 1.55 (95%CI: 1.10-2.19), respectively. Compared with non-breastfeeding children (OR=2.10, 95%CI: 1.39-3.17), children who were breastfeeding (OR=1.49, 95%CI: 1.00-2.20) exhibited consistently weaker effects, and the interaction effect of P value was 0.002.@*Conclusion@#Study findings indicate that long-term exposure to PM2.5 is associated with increased arterial BP and hypertension among the children. Breastfeeding may reduce this association.
ABSTRACT
<p><b>OBJECTIVE</b>To study the role of Th17/Treg imbalance in the immune pathogenesis and therapeutic significance in childhood aplastic anemia (AA).</p><p><b>METHOD</b>We analyzed data from 43 children (male: female = 14: 29) with AA, all the cases were at the age of 2 to 14 years at diagnosis, and were hospitalized at our department of pediatrics between January 2012 and October 2013 in the Second Hospital of Anhui Medical University. All these patients were divided into 2 groups, severe AA (SAA) group (n = 25, male: female = 8: 17, 2-14 years old) and non-severe AA (NSAA) group (n = 18, male: female = 6: 12, 2-14 years old), depending on the severity at first diagnosis. As to the treatment, we analyzed data at 3 phases of treatment, diagnosis (n = 43, male: female = 14: 29, 2-14 years old), transfusion-indenpendence (n = 8, male: female = 5: 3, 2-11 years old), complete response (n = 6, male: female = 3: 3, 2-11 years old); at the same time, AA children who did not respond to the treatments were considered as failed treatment control (transfusion-indenpendence with failed treatment group, n = 5, male: female = 1: 4, 3-8 years old; complete response failed treatment group, n = 4, male: female = 2: 2, 4-11 years old). The ratio of Treg and Th17 cells in CD4(+) T cells were tested by flow cytometry. The levels of IL-6 and IL-17 in plasma were determined by ELISA. During the same period, 25 age-matched healthy children (male: female = 12: 13, 3-14 years old) were recruited as normal control, 9 cases (male: female = 5: 3, 2-11 years old) of AA children induced by chemotherapy as diagnosis control group. Differences in variables were analyzed using ANOVA and t-tests or the Kruskal-Wallis and Mann-Whitney U-tests, as appropriate. Correlation analysis was evaluated by the Spearman rank correlation test.</p><p><b>RESULT</b>(1) The ratio of Th17 cells in newly diagnosed AA patients were higher than that of normal group or diagnosis control group [1.63% (1.27%, 2.48%) vs. 0.4% (0.35%, 0.51%) or 0.50% (0.45%, 0.75%), both P < 0.01] while the ratio of Treg cells was lower [4.24% (3.10%, 5.29%) vs. 7.03% (6.56%, 7.48%) or 7.50% (6.60%, 8.30%), both P < 0.01] and the proportion of Th17/Treg were significantly higher [0.53(0.34, 0.69) vs. 0.06 (0.05, 0.07) or 0.09 (0.08,0.11), both P < 0.01]. (2) The levels of IL-6 and IL-17 in newly diagnosed AA patients were higher than in normal group [ (223 ± 92) vs. (116 ± 18) ng/L, (26.2 ± 12.0) ng/L vs. (10.6 ± 2.1) ng/L, P both < 0.01]. There was a positive correlation between Th17 cells and some Th17 cells related cytokines such as IL-17 and IL-6 (r = 0.62, 0.64, P both < 0.01). (3) The ratio of Th17, Th17/Treg, and the levels of IL-6 and IL-17 in children with SAA were also higher than in normal group [1.80% (1.25%, 2.61%) vs. 0.40% (0.35%, 0.51%), 0.57% (5.10%,0.82%) vs. 0.06% (0.05%, 0.07%), (225 ± 108) vs. (116 ± 18) ng/L, (25.9 ± 12.6) vs. (10.6 ± 2.1)ng/L, all P < 0.01]. NSAA also higher than normal group. The ratio of Treg in children with SAA and NSAA was less than that in normal group (P all < 0.01). However, the ratio of Th17, Treg, Th17/Treg, and the levels of IL-6 and IL-17 had no significant difference between SAA and NSAA (all P > 0.05). (4) In different stages of treatment, such as diagnosis, transfusion-indenpendence, complete response, there were significant differences in the ratio of Th17 and Th17/Treg (both P < 0.05) but not in Treg (P > 0.05).</p><p><b>CONCLUSION</b>The imbalance of Th17/Treg cells and abnormally increased cytokines related to Th17 cells exist in peripheral blood of AA children, but did not significantly affect the severity of AA in preliminary diagnosis. After treatment with immunosuppression, AA was gradually relieved as the imbalance of Th17/Treg was corrected.</p>