Ayako Hashimoto

DIRECT EVIDENCE FOR ATOMIC DEFECTS IN GRAPHENE LAYERS

Atomic-scale defects in graphene layers alter the physical and chemical properties of carbon nanostructures. Theoretical predictions have recently shown that energetic particles such as electrons and ions can induce polymorphic atomic defects in graphene layers as a result of knock-on atom displacements. However, the number of experimental reports on these defects is limited. The graphite network in single-walled carbon nanotubes has been visualized by transmission electron microscopy (TEM) and their chiral indices have been determined. But the methods used require a long image acquisition time and intensive numerical treatments after observations to find an ‘average’ image, which prevents the accurate detection and investigation of defect structures. Here we report observations in situ of defect formation in single graphene layers by high-resolution TEM. The observed structures are expected to be of use when engineering the properties of carbon nanostructures for specific device applications.

Tumour exosome integrins determine organotropic metastasis.

Ever since Stephen Paget’s 1889 hypothesis, metastatic organotropism has remained one of cancer’s greatest mysteries. Here we demonstrate that exosomes from mouse and human lung-, liver- and brain-tropic tumour cells fuse preferentially with resident cells at their predicted destination, namely lung fibroblasts and epithelial cells, liver Kupffer cells and brain endothelial cells. We show that tumour-derived exosomes uptaken by organ-specific cells prepare the pre-metastatic niche. Treatment with exosomes from lung-tropic models redirected the metastasis of bone-tropic tumour cells. Exosome proteomics revealed distinct integrin expression patterns, in which the exosomal integrins α6β4 and α6β1 were associated with lung metastasis, while exosomal integrin αvβ5 was linked to liver metastasis. Targeting the integrins α6β4 and αvβ5 decreased exosome uptake, as well as lung and liver metastasis, respectively. We demonstrate that exosome integrin uptake by resident cells activates Src phosphorylation and pro-inflammatory S100 gene expression. Finally, our clinical data indicate that exosomal integrins could be used to predict organ-specific metastasis.

Oxidation resistance of Cr1−XAlXN and Ti1−XAlXN films

Cr1−XAlXN films were synthesized on mirror-polished stainless steel substrates by the arc ion plating method using Cr1−XAlX alloy targets with diffent Al contents. Oxidation resistance of films was estimated by heating substrates in air at 800, 900 and 1000 °C and subsequent analysis by the X-ray diffraction method (XRD). The XRD peaks from Ti0.7Al0.3N films, annealed at 800 °C for 14 h, disappeared and the peaks from iron oxides consequently appeared. The oxidation resistance of Ti1−XAlXN films improved with increasing Al content X. On the other hand, the peaks from Cr1−XAlXN films which were annealed at 800 °C did not change at all, but Cr1−XAlXN films were slightly oxidized over 900 °C. It is considered that the oxidation resistance of Cr1−XAlXN films was superior to that of Ti1−XAlXN films.

Adenomyosis and adverse perinatal outcomes: increased risk of second trimester miscarriage, preeclampsia, and placental malposition

Abstract Objective: To evaluate the potential impact of adenomyosis on the pregnancy outcomes by retrospectively investigating adenomyosis-complicated pregnancy cases. Methods: We performed a retrospective case–control study. Forty-nine singleton pregnancy cases complicated with adenomyosis were included in this study. The controls (n = 245) were singleton pregnant women without adenomyosis and were frequency matched to adenomyosis cases by age, parity, and the need for assisted reproductive technology for this conception. The incidence of obstetrical complications and delivery and neonatal outcomes were examined. Results: Patients in the adenomyosis group were significantly more likely to have a second trimester miscarriage (12.2% versus 1.2%, odds ratio (OR): 11.2, 95% confidence interval (95% CI): 2.2–71.2), preeclampsia (18.3% versus 1.2%, OR: 21.0, 95% CI: 4.8–124.5), placental malposition (14.2% versus 3.2%, OR: 4.9, 95% CI: 1.4–16.3), and preterm delivery (24.4% versus 9.3%, OR: 3.1, 95% CI: 1.2–7.2), compared with the control group. Conclusion: Adenomyosis was associated not only with an increased incidence of preterm delivery, as previously reported, but also with an increased risk of second trimester miscarriage, preeclampsia, and placental malposition, which could lead to poor perinatal outcomes.

Ternary nitride films synthesized by cathodic arc method

Changes in micro-structures and corresponding physical properties of ternary nitride films such as Ti 1-X Al X N, Ti 1-X Cr X N, Ti 1-X Zr X N, Cr 1-X Al X N and Zr 1-X Al X N were briefly summarized focused on micro-hardness with respect to different x value. The crystal structure and lattice parameter of ternary films change with x value and their physical properties correspondingly change as well. In this paper, the maximum hardness of ternary nitride films with particular x value was discussed based on the phase transition, analyzed by the X-ray diffraction method and transmission electron microscopy.