Structure of Yttrium and Phosphorus-Containing Microspheres Prepared by Spray Dry Method

Microspheres containing yttrium (Y) and/or phosphorus (P) around 25 µm are useful for radioembolization therapy because they are activated to β-emitter by neutron bombardment and infused in blood vessels in the neighborhood of tumors to irradiateβ-rays to the tumors. In this study, we attempt to prepare Y and P-containing microspheres by spray drying method. Starting solution containing yttrium nitrate and phosphoric acid in equimolar ratio was spray dried under various conditions. Microspheres 5-30 µm in size are obtained when the starting solution with polyvinyl alcohol (PVA) binder was spray-dried at the atomizing pressure of 0.05 MPa. When the microspheres were heated at 1100ºC for 1 h, they precipitated Y-containing crystals such as yttrium phosphate (YPO4), yttrium oxide (Y2O3), yttrium polyphosphate (Y(PO3)3) and yttrium tetraphosphate (Y2P4O13) but most of them were ruptured. Without the PVA binder, small microspheres around 5 µm in size were formed but their shape remained even after the heat treatment. We found that the atomizing pressure of spray dryer remarkably affects the size of microspheres and PVA binder is essential to obtain microspheres around 25 µm, but addition of pH adjuster to starting solution is not essential. This study proposed the criterion of conditions to prepare Y and P-containing microspheres by spray drying method

Low-temperature synthesis of crystalline GeSn with high Sn concentration by electron excitation effect

The low-temperature synthesis of high-Sn-concentration GeSn is challenging in realizing flexible thin-film transistors and solar cells. Because of athermal processes, irradiation with energetic particles is anticipated to significantly reduce the processing temperature for device fabrication. Here, we demonstrated that polycrystalline Ge with ~30 at. % Sn can be realized at room temperature by the electron-beam-induced recrystallization of amorphous GeSn. We found that inelastic electronic stopping, the so-called electron excitation effect, plays an important role in the recrystallization of amorphous GeSn

Gelatin hydrogel nonwoven fabrics of a cell culture scaffold to formulate 3-dimensional cell constructs

The objective of this study is to evaluate the possibility of gelatin hydrogel nonwoven fabrics (GHNF) of a cell culture scaffold to formulate 3-dimensional (3D) cell construct. The thickness of cell construct is about 1 mm and the cells inside are live and bio-active, irrespective of their internal distribution. The GHNF were prepared by the solution blow method of gelatin, following by dehydrothermal crosslinking. The GHNF showed a mechanical strength strong enough not to allow the shape to deform even in a wet state. The wet GHNF also showed resistance against repeated compression. After human mesenchymal stromal cells (hMSC) were seeded and cultured, the inner distribution in GHNF, the apoptosis, hypoxia inducible factor (HIF)-1α, Ki67, collagen or sulfated glycosaminoglycan (sGAG) secretion of cells were evaluated. The hMSC proliferated inside the GHNF with time while a homogeneous distribution in the number of cells proliferated from the surface to the 1000 μm depth of GHNF was observed. The number of apoptosis and HIF-1α positive cells was significantly low compared with that of polypropylene nonwoven fabrics with the similar fiber diameters and intra-structure. The GHNF were degraded during cell culture, and completely replaced by collagen and sGAG secreted. It is concluded that the GHNF is a promising cell culture scaffold for 3D cell constructs

New coronary aneurysm formation and malapposition after zotarolimus-eluting stent implantation in Kawasaki disease

AbstractCoronary artery involvement is the most important complication of Kawasaki disease. Coronary artery bypass surgery has been performed for ischemic heart disease caused by Kawasaki disease, however, long-term coronary graft patency is not satisfactory. Therefore, percutaneous coronary intervention (PCI) has its role in Kawasaki disease-related coronary artery disease. The incidence of new aneurysm is lower following stent implantation than balloon dilatation alone, even if a higher balloon pressure is applied. However, there are few reports about the efficacy of drug-eluting stent implantation for Kawasaki disease with coronary artery disease. Here, we describe a case of new coronary aneurysm formation and malapposition after zotarolimus-eluting stent implantation in Kawasaki disease.<Learning objective: New aneurysm formation after balloon angioplasty for coronary artery lesions in Kawasaki disease is a relatively well-known phenomenon, however there have been no reports about the influence of drug-eluting stents for coronary artery disease with Kawasaki disease. This report is useful when we consider strategies of revascularization for coronary artery disease with Kawasaki disease.

Quantitative Values from Synthetic MRI Correlate with Breast Cancer Subtypes

The purpose of this study is to correlate quantitative T1, T2, and proton density (PD) values with breast cancer subtypes. Twenty-eight breast cancer patients underwent MRI of the breast including synthetic MRI. T1, T2, and PD values were correlated with Ki-67 and were compared between ER-positive and ER-negative cancers, and between Luminal A and Luminal B cancers. The effectiveness of T1, T2, and PD in differentiating the ER-negative from the ER-positive group and Luminal A from Luminal B cancers was evaluated using receiver operating characteristic analysis. Mean T2 relaxation of ER-negative cancers was significantly higher than that of ER-positive cancers (p < 0.05). The T1, T2, and PD values exhibited a strong positive correlation with Ki-67 (Pearson’s r = 0.75, 0.69, and 0.60 respectively; p < 0.001). Among ER-positive cancers, T1, T2, and PD values of Luminal A cancers were significantly lower than those of Luminal B cancers (p < 0.05). The area under the curve (AUC) of T2 for discriminating ER-negative from ER-positive cancers was 0.87 (95% CI: 0.69–0.97). The AUC of T1 for discriminating Luminal A from Luminal B cancers was 0.83 (95% CI: 0.61–0.95). In conclusion, quantitative values derived from synthetic MRI show potential for subtyping of invasive breast cancers