Endothelial progenitor cells control remodeling of uterine spiral arteries for the establishment of utero-placental circulation.

Placental ischemia, resulting from inadequate remodeling of uterine spiral arteries, is a factor in the development of preeclampsia. However, the effect of endothelial progenitor cells that play a role in the vascular injury-repair program is largely unexplored during remodeling. Here, we observe that preeclampsia-afflicted uterine spiral arteries transition to a synthetic phenotype in vascular smooth muscle cells and characterize the regulatory axis in endothelial progenitor cells during remodeling in human decidua basalis. Excessive sEng, secreted by AMP-activated protein kinase (AMPK)-deficient endothelial progenitor cells through the inhibition of HO-1, damages residual endothelium and leads to the accumulation of extracellular matrix produced by vascular smooth muscle cells during remodeling, which is further confirmed by animal models. Collectively, our findings suggest that the impaired functionality of endothelial progenitor cells contributes to the narrowing of remodeled uterine spiral arteries, leading to reduced utero-placental perfusion. This mechanism holds promise in elucidating the pathogenesis of preeclampsia.

Effects of Temperature on Growth and Development of the Brown Planthopper, Nilaparvata lugens (Homoptera: Delphacidae).

The brown planthopper, Nilaparvata lugens (Stål), is one of the most serious and destructive pests of rice in Asia. Climate warming in tropical regions and extreme-high- or low-temperature events may become limiting factors affecting the survival and distribution of N. lugens. The effects of continuous high temperature (CHT), discontinuous high temperature (DHT), and abnormal low temperature in summer (ALT) on the growth and development of N. lugens were studied under lab conditions. High temperatures and ALT decreased the survival rate of nymphs (in fourth-instar nymphs, CHT, DHT, ALT, and control survival was 46.67% ± 1.67, 31.67% ± 1.67, 48.33% ± 4.41, and 60.00% ± 2.89, respectively, P < 0.05). ALT also prolonged the development of N. lugens nymphs (in fourth-instar nymphs, ALT and control survival was 6.09 ± 0.193 d and 5.39 ± 0.082 d, respectively, P < 0.05). In fifth-instar nymphs, CHT (2.36 ± 0.064 d, P < 0.05) and DHT (2.34 ± 0.048 d, P < 0.05) had little influence on nymphal development compared with the control (2.25 ± 0.012 d, P < 0.05). The three temperature treatments (CHT, DHT, and ALT) decreased the number of eggs produced (61.33 ± 0.067, 62.67 ± 0.882, and 34.00 ± 0.577, respectively, P < 0.05) compared with the control (68.00 ± 1.000, P < 0.05). The female sex ratio decreased after nymphs were subjected to CHT (65.82% ± 0.771, P < 0.05, in fifth-instar nymphs) and ALT (76.01% ± 1.362, P < 0.05) compared with the control (81.63% ± 1.007, P < 0.05). Adults in CHT (25.30 ± 0.182, P < 0.05) and DHT (14.64 ± 0.238, P < 0.05) consumed significantly more food than the control (11.54 ± 0.181, P < 0.05), but adults in ALT (6.54 ± 0.196, P < 0.05) fed significantly less than the control (11.54 ± 0.181, P < 0.05). Hatching rates of eggs under the three temperature treatments (CHT, DHT, and ALT were 69.57% ± 0.215, 71.29% ± 0.529, and 43.13% ± 0.508, respectively, and were significantly lower (P < 0.05) than the control (78.95% ± 1.000, P < 0.05). These experiments revealed that extreme temperatures can influence the growth and development of N. lugens and may affect its distribution. As such, N. lugens remains a serious pest of rice.

Preparation of restricted-access material precolumns by grafting δ-gluconolactone onto a hybrid silica monolithic column for on-line solid-phase extraction of tetracycline residues from milk.

A restricted-access material-hybrid monolithic column was prepared based on single-component organosiloxane and dynamic grafting of δ-gluconolactone for on-line solid phase extraction of tetracycline antibiotic residues from milk. The hybrid monolithic column was prepared in a stainless-steel chromatographic column using methyltrimethoxysilane as the single precursor. δ-Gluconolactone was covalently coupled to aminopropyl derivatized hybrid monolithic column, which formed hydrophilic structures on the surface of the pore of the restricted-access material-hybrid monolithic column. The columns were characterized by scanning electron microscopy, thermogravimetric analysis, Fourier transform infrared spectroscopy, nitrogen adsorption, contact angle analysis, dynamic adsorption, and chromatographic performance evaluation. The restricted-access material-hybrid monolithic column was applied to the on-line extraction of tetracycline residues from milk. An enrichment factor of 15.8 and a good sample clean-up effect were obtained under the optimized conditions. The recoveries of the three spiked milk samples were between 81.7 and 102.5% with relative standard deviations (n = 3) in the range of 2-5%. The limits of detection (S/N = 3) for target compounds were in the range of 3.80-9.03 µg/kg. The results show that the on-line extraction using the restricted-access material-hybrid monolithic column was powerful for food sample pretreatment with high selectivity and good clean-up effect.

Association between Genetic Variants of Transforming Growth Factor-ß1 and Susceptibility of Pneumoconiosis: A Meta-analysis.

BACKGROUND: Transforming growth factor-beta 1 (TGF-ß1) and gene variants have been extensively studied in various human diseases. For example, TGF-ß1 polymorphisms were associated with fibrosis and pneumoconiosis, but the data remained controversial. The aim of this meta-analysis was to assess the association between TGF-ß1 -509 C>T [rs1800469], +869 T>C [rs1800470], and +915 G>C [rs1800471] polymorphisms and pneumoconiosis. METHODS: A comprehensive literature search was conducted through searching in PubMed, Embase, the Chinese Biomedical Database, and the Wei Pu (Chinese) Database by the end of April 2016. Eleven publications with 21 studies were included in this meta-analysis, covering a total of 4333 patients with pneumoconiosis and 3478 controls. Study quality was assessed, and heterogeneity and publication bias were measured. All statistical analyses were performed using STATA version 12.0 (StataCorp, College Station, TX, USA) software. RESULTS: The data showed significant associations between TGF-ß1 -509 C>T polymorphism and the risk of pneumoconiosis development (T vs. C, odds ratio [OR] = 1.35, 95% confidence interval [CI]: 1.00-1.81, P = 0.046); between TGF-ß1 +915 G>C polymorphism and the pneumoconiosis risk (C vs. G, OR = 1.69, 95% CI: 1.19-2.40, P = 0.004; CG vs. GG, OR = 1.79, 95% CI: 1.23-2.60, P = 0.002; CC+CG vs. GG, OR = 1.80, 95% CI: 1.24-2.61, P = 0.002). In addition, the subgroup analysis of ethnicity versus pneumoconiosis types indicated a significant association of silicosis among Asian populations but not that of coal workers' pneumoconiosis in Caucasian populations. In contrast, no significant association was exhibited between TGF-ß1 +869 T>C polymorphism and risk of pneumoconiosis. CONCLUSION: The polymorphisms of both TGF-ß1 -509 C>T and +915 G>C are associated with increased risk of pneumoconiosis.

Detecting changes in ultrasound backscattered statistics by using Nakagami parameters: Comparisons of moment-based and maximum likelihood estimators.

The Nakagami distribution is an approximation useful to the statistics of ultrasound backscattered signals for tissue characterization. Various estimators may affect the Nakagami parameter in the detection of changes in backscattered statistics. In particular, the moment-based estimator (MBE) and maximum likelihood estimator (MLE) are two primary methods used to estimate the Nakagami parameters of ultrasound signals. This study explored the effects of the MBE and different MLE approximations on Nakagami parameter estimations. Ultrasound backscattered signals of different scatterer number densities were generated using a simulation model, and phantom experiments and measurements of human liver tissues were also conducted to acquire real backscattered echoes. Envelope signals were employed to estimate the Nakagami parameters by using the MBE, first- and second-order approximations of MLE (MLE1 and MLE2, respectively), and Greenwood approximation (MLEgw) for comparisons. The simulation results demonstrated that, compared with the MBE and MLE1, the MLE2 and MLEgw enabled more stable parameter estimations with small sample sizes. Notably, the required data length of the envelope signal was 3.6 times the pulse length. The phantom and tissue measurement results also showed that the Nakagami parameters estimated using the MLE2 and MLEgw could simultaneously differentiate various scatterer concentrations with lower standard deviations and reliably reflect physical meanings associated with the backscattered statistics. Therefore, the MLE2 and MLEgw are suggested as estimators for the development of Nakagami-based methodologies for ultrasound tissue characterization.