The placenta contributes to activation of the renin angiotensin system in twin-twin transfusion syndrome

The renin-angiotensin system (RAS) in twin-twin transfusion syndrome (TTTS) is up-regulated in the donor fetus's kidneys, but down-regulated in the recipient's. Ultrasonographic and echocardiographic features suggest that the recipient is also exposed to RAS components. In this study we investigated the role and origin of RAS components in the recipient fetus. Monochorionic diamniotic (MCDA) pregnancies were recruited from a tertiary fetal medicine service. Cord blood was collected from MCDA twins (TTTS and control non-TTTS) at delivery for renin and angiotensin II immunoassays. Placental tissue was flash-frozen for mRNA and protein expression or formalin-fixed for immunohistochemistry. Archival placenta and kidney samples were used for immunohistochemistry and in-situ hybridization. Plasma renin levels were elevated (p<0.05) in recipients (median 201pg/ml, range 54-315pg/ml) and donors (125pg/ml, 25-296) with TTTS compared to controls (2.5pg/ml, 1.1-1.5pg/ml). The same was found with angiotensin II with high levels in both recipients (300.5pg/ml, 86.1-488pg/ml) and donors (239pg/ml, 76.6-422) compared to controls (169.5pg/ml, 89-220pg/ml, p<0.05). Renin mRNA expression, and protein appeared qualitatively higher in the placental territory of the recipient compared to that of the donor and non-TTTS controls. We conclude that both fetuses in TTTS are exposed to high levels of RAS components; these appear to be produced from different sites, namely the kidney of the donor, and the placenta of the recipient. Given the markedly different phenotypes in the genetically identical fetuses with TTTS, we suggest that the source of RAS components may influence their clinical manifestations.     

Down syndrome biochemical markers and screening for preeclampsia at first and second trimester: correlation with the week of onset and the severity

OBJECTIVES: To estimate the combined screening performance of first and early second trimester prenatal serum markers for Down syndrome, in screening for the development of preeclampsia, and analyze the correlation among marker levels, week of onset, and severity of the disease. METHODS: A retrospective cohort study was carried out on 32 women with preeclampsia and 3044 controls. Serum samples from these pregnancies were assayed for pregnancy-associated plasma protein-A (PAPP-A), alpha-fetoprotein (AFP), unconjugated estriol (uE3), human chorionic gonadotrophin (hCG), and inhibin-A. A likelihood ratio and the odds of being affected given a positive result (OAPR) of various combinations of markers were calculated and receiver operating characteristic (ROC) curves analysis was performed. RESULTS: In the pregnancies that subsequently developed preeclampsia, first trimester PAPP-A concentration was significantly lower and concentrations of early second trimester inhibin-A and hCG significantly elevated. Levels of early second trimester uE3 and AFP were not significantly altered. We also found that inhibin-A correlates with both onset of the disease and the severity. CONCLUSION: Down syndrome biochemical markers levels are altered in those patients who subsequently developed preeclampsia and may be a useful screening test for preeclampsia. Inhibin-A is the most predictive marker and correlates with the severity of subsequent preeclampsia and inversely with the week of occurrence of preeclampsia.     

Clinical impact of integrated PET/CT on the management of suspected cervical cancer recurrence

OBJECTIVES: To assess the value and clinical impact of integrated PET/CT using (18)F-FDG in the diagnosis and management of women with suspected cervical cancer recurrence. METHODS: Fifty-two patients with cervical cancer with suspected recurrence because of clinical, cytological, biochemical and radiological findings were retrospectively evaluated. A final diagnosis of recurrence was confirmed by histologic tissue biopsy or by further clinical or radiological evidence. The clinical impact of information provided by PET/CT on patient management was assessed on the basis of clinical follow-up data concerning further diagnostic or therapeutic approach. RESULTS: Twenty-eight of 32 positive PET/CT scans (87.5%) were proven to have recurrent disease. Seventeen of 20 negative PET/CT scans (85.0%) had no evidence of disease. The sensitivity, specificity, and accuracy of PET/CT for detecting recurrence were 90.3%, 81.0%, and 86.5% respectively. PET/CT changed the management of 12 patients (23.1%) by changing treatment plan (5 patients), by initiating unplanned treatment strategy (4 patients), or by obviating the need for planned diagnostic procedures (3 patients). Median duration after performing PET/CT and last follow-up was 12 (range: 6-27) months, and the 2-year disease-free survival rate of patients with negative PET/CT scan for recurrence was significantly better than that of patients with positive PET/CT (85.0% vs. 10.9%, P=0002). CONCLUSIONS: In patients with a suspected recurrence of cervical cancer, integrated PET/CT using (18)F-FDG provides good anatomic and functional localization of suspicious lesions, and the better diagnostic interpretation has an impact not only on clinical management and treatment planning of patients, but also on disease-free survival.     

Antioxidant capacity and phenolic content of selected commercially available cruciferous vegetables

Antioxidant activity, free radical scavenging activity and phenolic content of red cabbage (Brassica oleracea var. capitata rubra), Chinese cabbage (Brassica rapa pekinensis var cylindrica), green cabbage (Brassica oleracea var capitata), mustard cabbage (Brassica juncea var rugosa) and Chinese white cabbage (Brassica rapa var chinensis), grown in Malaysia, were evaluated. Red cabbage had the highest antioxidant activity and phenolic content compared to the other cruciferous vegetables studied (p < 0.05). The contributions of all cruciferous vegetables to the antioxidant activity was >79%. The radical scavenging activity was in the order of Chinese white cabbage > red cabbage > mustard cabbage > Chinese cabbage > green cabbage. There was a significant difference (p < 0.05) in the means of scavenging activity observed between cabbage, Chinese cabbage and Chinese mustard. Phenolic content was significantly different (p < 0.05) among all the cruciferous vegetables studied, and was in the order of red cabbage > Chinese white cabbage > green cabbage > Chinese cabbage >mustard cabbage. The study indicated that red cabbage possessed the highest antioxidant capacity and phenolic compounds concentration among all the cruciferous vegetables studied.     

Artificial Neural Network Modelling of the Effect of Vanadium Addition on the Tensile Properties and Microstructure of High-Strength Tempcore Rebars

In high-strength rebar, the various microstructures obtained by the Tempcore process and the addition of V have a complex effect on the strength improvement of rebar. This study investigated the mechanism of strengthening of high-strength Tempcore rebars upon the addition of vanadium through artificial neural network (ANN) modelling. Various V contents (0.005, 0.072 and 0.14 wt.%) were investigated, and a large amount of bainite and V(C, N) were precipitated in the core of the Tempcore rebar in the high-V specimens. In addition, as the V content increased, the number of these fine precipitates (10–30 nm) increased. The precipitation strengthening proposed by the Ashby–Orowan model is a major contributing factor to the yield-strength increase (35 MPa) of the Tempcore rebar containing 0.140 wt.% V. The ANN model was developed to predict the yield and tensile strengths of Tempcore rebar after the addition of various amounts of V and self-tempering at various temperatures, and it showed high reproducibility compared to the experimental values (R-square was 93% and the average relative error was 2.6%). ANN modelling revealed that the yield strength of the Tempcore rebar increased more significantly with increasing V content (0.01–0.2 wt.%.) at relatively high self-tempering temperatures (≥530 °C). These results provide guidelines for selecting the optimal V content and process conditions for manufacturing high-strength Tempcore rebars.     

Effects of Interleukin-17A on the Early Stages of Arterial Thrombosis in Mice

PurposeInterleukin (IL)-17A has been suggested to play a role in the growth and organization of thrombi. We examined whether IL-17A plays a role in the early stages of thrombosis and whether there are sex differences in the effects of IL-17A.Materials and MethodsWe performed a blinded, randomized, placebo-controlled study to compare time to thrombotic occlusion and sex differences therein between mice treated with IL-17A and those treated with saline using a ferric chloride-induced model. We also assessed thrombus histology, blood coagulation, and plasma levels of coagulation factors.ResultsTime to occlusion values did not differ between the IL-17A group and the control group (94.6±86.9 sec vs. 121.0±84.4 sec, p=0.238). However, it was significantly shorter in the IL-17A group of female mice (74.6±57.2 sec vs. 130.0±76.2 sec, p=0.032). In rotational thromboelastometry, the IL-17A group exhibited increased maximum clot firmness (71.3±4.5 mm vs. 66.7±4.7 mm, p=0.038) and greater amplitude at 30 min (69.7±5.2 mm vs. 64.5±5.3 mm, p=0.040) than the control group. In Western blotting, the IL-17A group showed higher levels of coagulation factor XIII (2.2±1.5 vs. 1.0±0.9, p=0.008), monocyte chemoattractant protein-1 (1.6±0.6 vs. 1.0±0.4, p=0.023), and tissue factor (1.5±0.6 vs. 1.0±0.5, p=0.003).ConclusionIL-17A plays a role in the initial st ages of arterial thrombosis in mice. Coagulation factors and monocyte chemoattractant protein-1 may be associated with IL-17A-mediated thrombosis.     

Friction Properties of Solid Lubricants with Different Multiwalled Carbon Nanotube Contents

Bushes are circular bearings that surround a shaft and help it rotate smoothly. In heavy equipment, bushes are coated with solid lubricants to reduce friction. Although the coating layer of the lubricant has a stable coefficient of friction (CoF), it is important that this should last for a long time. In this study, multiwalled carbon nanotubes (MWCNTs), which have a low CoF, were added to the lubricant to improve its performance. When 2.3 wt% MWCNTs were added to the polymer resin, the dynamic CoF (under a 29 N external load) decreased by 78% in relation to that of the resin without MWCNTs. As the MWCNT content increased, the roughness of the coating decreased, which reduced the CoF. Moreover, MWCNT addition increased the overall tensile strength owing to an increase in the bonding force between the resins. Under a high load of 20 tonnes (t), the MWCNT-based solid lubricant had a CoF of 0.05, lower than commercial MoS₂-based solid lubricants; this was maintained for more than 10,000 cycles in a bush and shaft test. With the MWCNT-based solid lubricant, a lubricating polymer film formed, even on worn bush surfaces. The CoF of the solid lubricant was reduced and the number of cycles with a constant CoF increased when MWCNTs were added owing to the formation of the lubricating polymer film.     

Comparative effect of genistein and daidzein on the expression of MCP-1, eNOS, and cell adhesion molecules in TNF-��-stimulated HUVECs

We compared the effects of genistein and daidzein on the expression of chemokines, cell adhesion molecules (CAMs), and endothelial nitric oxide synthase (eNOS) in tumor necrosis factor (TNF)-α-stimulated human umbilical vascular endothelial cells (HUVECs). TNF-α exposure significantly increased expression of monocyte chemoattractant protein (MCP)-1, vascular adhesion molecule (VCAM)-1, and intercellular adhesion molecule-1. Genistein significantly decreased MCP-1 and VCAM-1 production in a dose-dependent manner, whereas CAM expression was not significantly lowered by genistein treatment. However, daidzein slightly decreased MCP-1 production. The effects of genistein and daidzein on MCP-1 secretion coincided with mRNA expression. Pre-treatment with either genistein or daidzein elevated eNOS expression and nitric oxide production disturbed by TNF-α exposure. A low concentration of isoflavones significantly inhibited nuclear factor (NF)κB activation, whereas a high dose slightly ameliorated these inhibitive effects. These results suggest that genistein had a stronger effect on MCP-1 and eNOS expression than that of daidzein. Additionally, NFκB transactivation might be partially related to the down-regulation of these mRNAs in TNF-α-stimulated HUVECs.