The Value of Ultrasonography in Assessing Fetal Lung Maturity.

OBJECTIVE: To establish the normal parameters of fetal lung development at different gestational ages and to study their correlation with gestational age, thereby providing clinicians with a noninvasive method for assessing fetal lung maturity. METHODS: Two hundred eight cases with pregnancy of 22 to 39 weeks plus 6 days were divided into 18 groups according to gestational age. Ultrasound Doppler was used to measure the relevant parameters of fetal pulmonary development, including right pulmonary left and right diameter, right pulmonary upper and lower diameter, right pulmonary anterior and posterior diameter, right pulmonary area, thoracic area, inner diameter of fetal main pulmonary artery, and Doppler velocity curve parameters of main pulmonary artery: systolic acceleration time (AT), ejection time (ET), AT/ET. RESULTS: This study establishes normal parameters of lung development at different gestational weeks, draws scatter plots, correlation, and regression analysis of fetal main pulmonary artery AT, ET, AT/ET, and gestational weeks; selects the optimal equation; and analyzes the correlation among right pulmonary left and right diameter, right pulmonary upper and lower diameter, right pulmonary anterior and posterior diameter, right lung diameter, right lung area, thoracic area, and gestational weeks; and draw growth curve. The diameter of main pulmonary artery, AT, and AT/ET increased with the increase of gestational age and were positively correlated with gestational age (r = 0.948, 0.875, 0.810; P = 0.012). Ejection time had no correlation with gestational weeks. There were significant differences in the diameter of main pulmonary artery, AT, AT/ET between different gestational weeks (F = 240.67, 41.137, 23.067; P = 0.024); left and right diameter of right lung, anterior and posterior diameter of right lung, upper and lower diameter of right lung, chest area and right lung area were positively correlated with gestational weeks, and there were significant differences between different gestational weeks (F = 190.85, 105.74, 34.97, 172.33, 35.33, P = 0.018). CONCLUSIONS: Ultrasound Doppler can be used as a noninvasive detecting equipment to evaluate the growth of fetal lung, thus providing a basis for the evaluation of fetal lung maturity.

Clinical Analysis of Fetal Lung Development Index and Pregnancy Outcome in Pregnant Women with Gestational Diabetes Mellitus with Satisfactory Blood Glucose Control.

Objective: To explore the regularity of fetal lung development of pregnant women with gestational diabetes mellitus (GDM) with satisfactory blood glucose control and the clinical analysis with pregnancy outcome. Methods: 120 GDM pregnant women with satisfactory blood glucose control (GDM group) and 200 normal pregnant women undergoing prenatal examination (Control group) from 31 to 38 + 6 weeks of gestation were included. The two groups of pregnant women were divided into 8 time periods according to the gestational age, respectively. The parameters of Doppler flow velocity curve of fetal main pulmonary artery, diameter lines of fetal lung development, mode of delivery, neonatal weight, neonatal asphyxia, neonatal respiratory distress syndrome (NRDS), and neonatal pneumonia were, respectively, compared and analyzed between the two groups. Results: Acceleration time (AT) and AT/ejection time (AT/ET) were positively correlated with gestational age, and AT/ET showed stronger correlation than AT, while no significant difference in AT and AT/ET between the two groups (P > 0.05). There was a positive correlation between the diameter of fetal lung development and gestational age, but there was no significant difference between the two groups (P > 0.05). In addition, there was no significant difference between the two groups in fetal delivery mode, neonatal weight, neonatal asphyxia, NRDS, and neonatal pneumonia (P > 0.05). Conclusion: AT/ET may be a potential index to evaluate fetal lung maturity. There was no difference in fetal lung development and neonatal birth outcome between pregnant women with satisfactory GDM blood glucose control and the normal pregnant women. The pregnancy of GDM pregnant women lasts until the end of 37∼38 weeks, and the neonatal incidence rate is decreased. The key is to manipulate the blood glucose in the normal range.

Spatial distribution and morphological transformation of chromium with coexisting substances in tannery landfill.

The prosperity and development of tannery industry have brought about rapid economic growth. However, the tannery landfill without anti-seepage measures in the early stage has generated masses of environmental hazards owing to the lack of awareness in environmental protection. Therefore, it is imperative to pay much attention to the understanding of environmental hazards from tannery waste. In this study, solid samples and groundwater samples were collected from a tannery landfill to study the effect of the characteristic pollutants produced by tanning on chromium distribution with other coexisting substances. The results showed that significant correlations were demonstrated between multiple coexisting substances (total organic carbon, total petroleum hydrocarbons, total nitrogen, Cr, F, Ca, Cu and Pb), indicating the possible same source or they coming from the same tannery production stage. The weights of positive effects and negative effects of coexisting substances on total Cr distribution in the profile decreased in the order: total nitrogen > Cu > Ca > Pb > total organic carbon > F > SO42-> Cd, and Ni > Cl > Hg, respectively. Moreover, the simulation of Visual MINTEQ showed that the cations were mainly bound to Cr as CrO42-, while the anions were bound to Cr3+. This study provided a new perspective on the selection of remediation strategies for Cr-contaminated sites to avoid secondary environmental pollution caused by the release of coexisting heavy metals.

[Phosphorus fractions, sorption characteristics and its release in the sediments of Yangtze Estuary Reservoir, China].

To analyze the sediment phosphorus (P) fractions and sorption characteristics and P release from sediment of reservoir in Yangtze estuary, the sediment was investigated during April, 2011 to January, 2012. Results of chemical fractionation analysis showed that total P (TP) content in sediment ranged from 535.07 to 910.9 mg x kg(-1), inorganic P (IP) was a dominant component of TP and the content of organic P (OP) was low. IP presented in the form of P bounded to calcium ( HCl-P) and dominated 75.57% of TP. The batch experiments showed that sediments had the maximum P adsorption capacity from 9.78 to 39.84 mg x kg(-1), sorption data fitted the modified Langmuir isotherm model. However, EPC0 ( equilibrium phosphorus concentration) in all sampling sites was higher than the soluble-reactive P concentration in water column, which was from 0.024-0.12 mg x L(-1). Accordingly, the sediments from those sampling sites would release phosphorus into the overlying water as a P release source. The maximum released amount from sediment was 11.03 mg x kg(-1) about 6 hours. Correlation between P released amount and NaOH-P was found (P < 0.01), and sediment P release would mainly originate from the NaOH-P, OP and HCl-P fraction. It is evident that the inherent phosphorus present in sediments would be a major threat to the water quality in Yangtze River estuary reservoir.