Refractory angina is an independent predictor of adverse events in patients with vasospastic angina (VSA). The aim of this study was to investigate the relationship between coronary lumen complexity and refractory symptoms in patients with VSA. Seventeen patients with VSA underwent optical coherence tomography. The patients were divided into the refractory VSA group (n = 9) and the stable VSA group (n = 8). A shoreline development index was used to assess the coronary artery lumen complexity. Shear stress was estimated using a computational fluid dynamics model. No difference was observed in the baseline characteristics between the two groups. The refractory VSA group showed the higher shoreline development index (refractory VSA 1.042 [1.017–1.188] vs stable VSA 1.003 [1.006–1.025], p = 0.036), and higher maximum medial thickness (refractory VSA 184 ± 17 μm vs stable VSA 148 ± 31 μm, p = 0.017), and higher maximum shear stress (refractory VSA 14.5 [12.1–18.8] Pa vs stable VSA 5.6 [3.0–10.5] Pa, p = 0.003). The shoreline development index positively correlates with shear stress (R² = 0.46, P = 0.004). Increased medial thickness of the coronary arteries provokes lumen complexity and high shear stress, which might cause refractory symptoms in patients with VSA. The shoreline index could serve as a marker for irritability of the medial layer of coronary arteries and symptoms.

An ArF excimer laser deposition technique is used to fabricate hydroxyapatite [Ca₁₀(PO₄)₆(OH)₂]-(HAp) thin films on surface-modified polytetrafluoroethylene (PTFE) substrates. The surface of PTFE is modified by a sodium-naphthalene complex in a glycol ether solvent. X-ray diffraction (XRD) studies indicate that as-deposited films prepared at substrate temperatures below the glass transition temperature of PTFE (327°C) are in an amorphous state. The crystallization of as-deposited films needed annealing for 10 h at 310°C. The structure, surface morphology and bond strength of HAp films were evaluated using XRD, the atomic force microscopy (AFM) and the Instron testing machine. The tensile bond strength of HAp films on surface-modified PTFE was 6.0 MPa, which is one order of magnitude larger than that of films on non-surface-modified PTFE, demonstrating its potential for practical applications.

A microforce sensor with a force feedback method for scanning force microscopy is presented. The force sensor is constructed by using an optical fiber and a microcantilever. The facet of the optical fiber is coated with a gold thin film 15 Å thick. This gold film acts not only as a partially reflected mirror but also as an electrode of the electrostatic actuator. The interaction force between a probe tip and a sample is balanced by the electrostatic force. The deflection of the cantilever is measured by an interferometer consisting of the facet of the optical fiber and the cantilever surface. We have made the force sensor and measured some force curves of a mica surface with a SiN probe tip. The force curves obtained by this sensor are quite different from the curves by a conventional measurement without a feedback system. The force resolution of the system is 10${}^{\text{−10}}$ N with a bandwidth of dc∼1 kHz.

Classical preimplantation embryo culture is performed in static fluid environments. Whether a dynamic fluid environment, like the fallopian tube, is beneficial for embryo development remains to be determined across mammalian species. Objectives of these proof-of-concept studies were to determine if controllable dynamic microfluidic culture would enhance preimplantation murine, bovine, and human embryo development compared to static culture. This prospective randomized controlled trial tested static versus controlled dynamic culture of preimplantation mouse (n = 397), bovine (n = 242), and human (n = 512) zygotes to blastocyst stages with outcome measures of embryo cleavage, cellular fragmentation, apoptosis, and blastocyst conversion rates. Dynamic culture of mouse and bovine zygotes with microfluidics significantly improved embryo development. Mouse placental imprinted gene expression was significantly different between embryos derived in vivo, by static culture, and by dynamic culture. Using human sibling zygotes, this dynamic microfluidic culture system increased the number of blastomeres per cleavage-stage embryo, reduced cellular fragmentation or apoptosis, improved blastocyst conversion rates, and enhanced blastocyst developmental stages. In conclusion, species-specific longitudinal studies demonstrated that dynamic microfluidic culture significantly improved embryo development, independent of culture media composition, temperature, and gaseous environment. These cellular indicators represent improved embryo development that can translate into higher pregnancy rates in transgenics, domestic livestock and endangered species and treating human infertility.