Facile Preparation of Polysiloxane-Modified Asphalt Binder Exhibiting Enhanced Performance.

The development of polymer-modified asphalt (asphalt = asphalt binder) is significant because the polymer modifier can improve the performance of asphalt mixture and meet the requirements of the modern asphalt pavement. Herein, we present a novel polysiloxane-modified asphalt with enhanced performance, formed by simply mixing hydroxy-terminated polysiloxane (HO-PDMS) into base asphalt at 140 °C. The interaction mechanism of HO-PDMS in base asphalt was characterized by FT-IR, GPC, and DSC. It reveals that HO-PDMS polymers have been chemically bonded into the asphalt, and, thus, the resultant asphalt exhibits optimal compatibility and storage stability. The results based on fluorescence microscopy and a segregation test prove that HO-PDMS has good compatibility with base asphalt. Moreover, by virtue of the intriguing properties of polysiloxane, the present asphalt possesses improved low- and high-temperature properties, higher thermal stability, and enhanced hydrophobicity compared to conventional asphalt when using an appropriate dosage of HO-PDMS. DSC indicated that the Tg of modified asphalt (-12.8 °C) was obviously lower than that of base asphalt (-7.1 °C). DSR shows that the rutting parameter of modified asphalt was obviously higher than that of base asphalt. BBR shows that modified asphalt exhibited the lowest stiffness modulus and the highest creep rate with an HO-PDMS dosage of 6% and 4%, respectively. These results demonstrate that polysiloxane-modified asphalt can be promisingly utilized in realistic asphalt pavement with specific requirements, particularly high-/low-temperature resistance.

Pseudo null growth model and its classifications based on generalized vortex filament equation.

The pseudo null growth model in Minkowski 3-space is shaped by evolving a pseudo null curve as denoted direction, growth velocity, and stretch in this paper. Meanwhile, the idea of the generalized Hasimoto surfaces is proposed based on the vortex filament equation. The conditions and geometric structures of the generalized Hasimoto pseudo null growth surfaces are investigated accompanied by some typical examples.

miR-21 down-regulation promotes apoptosis and inhibits invasion and migration abilities of OVCAR3 cells.

PURPOSE: To investigate the influence of miR-21 down-regulation on cell proliferation, apoptosis, invasion and migration of ovarian papillary adenocarcinoma cell lines (OVCAR3). METHODS: Short-hairpin RNA (shRNA), specifically targeting miR-21, was constructed and transfected into OVCAR3 cells using the pSIREN-RetroQ linear vector (pSIREN-miR-21). The expression of miR-21 was detected with stem-loop real-time RT-PCR in OVCAR3 cells. Cell proliferation and apoptosis were monitored using the MTT assay and flow cytometry, respectively. Cell migration and invasion were assessed using the transwell migration and scratch-wound assay, respectively. Western-bloting was used for PDCD4 protein expression. RESULTS: pSIREN-miR-21 suppressed miR-21 expression in OVCAR3 cells. miR-21 expression levels in pSIREN-miR-21 cells was 0.3 ± 0.1, which was significantly lower when compared with pSIREN-miR-21-Neg and control groups (P < 0.01). Cell inhibition rate in the pSIREN-miR-21 group was higher than the control group (29.4% vs 9.0%, P < 0.01), as was the percentage of apoptotic and necrotic cells. By transwell migration assay, the number of cells migrating in the pSIREN-miR-21 group was significantly lower than in the control group. In addition, fewer cells were observed in the wounded area of the pSIREN-miR-21 group following the scratch-wound assay. PDCD4 expression was increased in OVCAR-3 cells transfected by pSIREN-miR-21 compared with vector-control transfected cells. Moreover, the optical density of the transfected cells was significantly lower than the two control groups. CONCLUSION: Down-regulation of miR-21 dramatically increased apoptotic cell death and decreased cell proliferation, invasion and migration in OVCAR3 cells. MiR-21 may play an important role in the biological behaviors of epithelial ovarian carcinoma cells through negative control of the expression of PDCD4.

Natural selection on TMPRSS6 associated with the blunted erythropoiesis and improved blood viscosity in Tibetan pigs.

Tibetan pigs, indigenous to Tibetan plateau, are well adapted to hypoxia. So far, there have been not any definitively described genes and functional sites responsible for hypoxia adaptation for the Tibetan pig. The whole genome-wide association studies in human suggested that genetic variations in TMPRSS6 was associated with hemoglobin concentration (HGB) and red cell counts (RBC). Here we conducted resequencing of the nearly entire genomic region (40.1 kb) of the candidate gene TMPRSS6 in 40 domestic pigs and 40 wild boars along continuous altitudes and identified 708 SNPs, in addition to an indel (CGTG/----) in the intron 10. We conduct the CGTG indel in 838 domestic pigs, both the CGTG deletion frequency and the pairwise r2 linkage disequilibrium showed an increase with elevated altitudes, suggesting that TMPRSS6 has been under Darwinian positive selection. As the conserved core sequence of hypoxia-response elements (HREs), the deletion of CGTG in Tibetan pigs decreased the expression levels of TMPRSS6 mRNA and protein in the liver revealed by real-time quantitative PCR and western blot, respectively. We compared domestic pigs and Tibetan pigs living continuous altitudes, found that the blood-related traits with the increase of altitude, however, the HGB did not increase with the elevation in Tibetan pigs. Genotype association analysis results dissected a genetic effect on reducing HGB by 13.25 g/L in Gongbo'gyamda Tibetan pigs, decreasing mean corpuscular volume (MCV) by 4.79 fl in Diqing Tibetan pigs. In conclusion, the CGTG deletion of TMPRSS6 resulted in lower HGB and smaller MCV, which could reflect a blunting erythropoiesis and improving blood viscosity as well as erythrocyte deformability. It remains to be determined whether a blunting of erythropoiesis for TMPRSS6 or others genetic effects are the physiological adaptations among Tibetan pigs.

Women heterozygous for NALP7/NLRP7 mutations are at risk for reproductive wastage: report of two novel mutations.

Familial recurrent hydatidiform moles are a rare recessive condition in which molar tissues have biparental contribution to their genome. One maternal locus responsible for this condition has been mapped to 19q13.4 and the causative gene, NALP7, identified (HUGO-approved nomenclature is now NLRP7). Here we report a first stop codon, c.295G>T (p.Glu99X) and a missense mutation, c.1970A>T (p.Asp657Val) in NLRP7 in two sisters with RHMs. We found these two mutations and a previously reported one, c.2078G>C (p.Arg693Pro) in a homozygous state, in males with normal reproductive outcomes. This suggests that NLRP7 is not required for normal spermatogenesis. The mother of the patients is heterozygous for Glu99X and had one stillbirth and three normal pregnancies. Our data on this new family and on heterozygous women from previously reported families indicate that women heterozygous for NLRP7 mutations are at risk for reproductive wastage without the manifestation of molar phenotype.

Expression and roles of TIPE2 in autoimmune hepatitis.

Tumor necrosis factor, alpha-induced protein 8-like 2 (TIPE2) is associated with the development of hepatic inflammatory diseases. However, to date, the possible role of TIPE2 in autoimmune hepatitis (AIH) has not been reported. The present study aimed to investigate the expression of TIPE2 in peripheral blood mononuclear cells (PBMCs) of mice with AIH. Furthermore, the liver function, pro-inflammatory cytokine production and hepatic histopathology were examined in TIPE2-deficient mice in order to evaluate whether TIPE2 is involved in the pathogenesis of AIH. A murine model of AIH was induced by treatment with concanavalin A (ConA). The expression of TIPE family members in the PBMCs was examined using reverse-transcription quantitative polymerase chain reaction analysis, while the protein expression of TIPE2 was additionally detected by western blot analysis. The activity of alanine amiotransferase (ALT) and aspartate aminotransferase (AST) in the serum was measured on an automated chemical analyzer to assess liver function. The serum levels of tumor necrosis factor-α, interleukin (IL)-6 and IL-12 were measured using commercial ELISA kits. Hematoxylin and eosin staining was performed to assess hepatic histopathology. The results showed that the expression of TIPE2 was significantly decreased in the mice with AIH. Following ConA-induced AIH, TIPE2-deficient mice had significantly increased serum ALT and AST levels, enhanced production of pro-inflammatory cytokines, as well as more severe hepatic inflammation compared with the wild-type mice. In conclusion, the present study demonstrated, for the first time, that TIPE2 is involved in the pathogenesis of AIH. TIPE2 prevents liver dysfunction and inhibits deleterious inflammatory immune responses after AIH and may therefore serve as a novel agent for the treatment of AIH.

[Expression of microRNA-21 in ovarian epithelial carcinoma and its clinical significance].

OBJECTIVE: To investigate the expression of microRNA-21(miR-21) in ovarian epithelial carcinoma and its association with the clinicopathological features. METHODS: The expression of miR-21 was detected by Stem-loop real-time RT-PCR in 48 cases of ovarian epithelial carcinomas, 24 cases of benign ovarian epithelial tumors and 15 cases of normal ovarian tissues. RESULTS: The relative expression level of miR-21(2-(DeltaDelta)CT) was 4.849-/+1.813 in the ovarian epithelial carcinomas, significantly higher than that in the benign ovarian tumors and normal ovarian tissues (P<0.01), but comparable between the latter two groups. The expression of miR-21 was not correlated to the histological type, but increased significantly with the progression of the clinical stages and histological grading (P<0.01), showing a close correlation to lymphatic metastasis. CONCLUSION: MiR-21 might play a role as an oncogene in the tumorigenesis and development of ovarian epithelial carcinoma, and is possibly correlated to the progression and prognosis of ovarian epithelial carcinoma.