RESUMEN
Our cognitive processing is flexible and affected by global/local dominance in prior cognitive tasks. Similar to cognitive processing, perceptual processing, especially colour perception related to global/local processing, may be affected by prior global/local dominance; however, this possibility has not yet been assessed. Here, we examined whether prior tasks involving global/local processing influenced colour perception related to global/local processing. As colour perception is related to global/local processing, we focused on perceived colour transparency, in which a transparent layer is perceived in front of a background layer, even though these stimuli are physically in the same layer. When viewing the colour transparency stimulus, we expected that the perceived colour of a specific region, when focusing on only the local region, would differ from that when focusing on the whole image. In our study, the participants completed a global or local Navon task, followed by a colour-matching task that assessed how they saw colours using colour transparency stimuli. The degree of optical illusion (i.e., perceived colour transparency) after the global Navon task was greater than that after the local Navon task. Thus, prior global/local processing, a flexible mode of cognitive processing, influenced colour perception. This study provides new insight into perceptual flexibility, especially in colour perception.
RESUMEN
Circulating tumor cells (CTCs) are tumor cells that originate from primary cancer tissues, enter the bloodstream in the body, and metastasize to the other organs. Simple and convenient methods for their detection, capture, and recovery from the blood of cancer patients would be highly desirable. We report here on a simple and convenient methodology to trap, culture, and re-collect cancer cells, the sizes of which are greater than those of normal hematologic cells, by the use of glass-bead filters (GBFs). We prepared GBFs with a diameter of 24 mm and thicknesses of 0.4 mm and 1.2 mm, with well-defined pores, by sintering round-shaped glass beads (diameter: 63-106 µm). A small integrated glass-bead filter (iGBF) with a diameter of ca. 9.6 mm for the use in filtering a small volume of blood was also designed and prepared. Using GBF and iGBF, it was possible to efficiently capture mouse Lewis lung carcinoma cells expressing green fluorescent protein spiked in saline/blood by single and repeated (circulation) filtrations in in vitro experiments with very small amounts of red blood cells being captured. In addition, we successfully captured B16 CTCs from the blood of a B16 melanoma metastasis mouse model by iGBF. Cancer cells/CTCs captured on/in the GBF could be cultured and efficiently recovered from the filters. Filtration by GBF had negligible effect on the adherent and proliferative characteristics of cancer cells. Simple and convenient methods for the capture, culture, and re-collection of CTCs by GBF along with flexibility of GBF, which permits them to be molded into suitable architectures having the desired shape and size, should be useful for early and convenient diagnosis and treatment of cancer and related diseases.
RESUMEN
In the field of biological microscopy technology, it is still a practical challenge to obtain high-quality tissue images, due to the tissue desiccation that occurs during observations without an effective sample mounting. Inspired by the use of plastic food wrap, this study proposes the use of polymer thin films (also known as nanosheets) to fix the tissue samples. Water-repellent nanosheets composed of the amorphous fluoropolymer CYTOP are prepared with adjustable thicknesses and their hydrophobicity, transparency, and adhesion strength are evaluated. They show excellent water-retention effect and work well for sample fixation. By wrapping cleared mouse brain slices with a 133 nm thick CYTOP nanosheet, this study achieves high spatial resolution neuron images while scanning over a large area for a long period of time. No visible artifacts arising from sample shrinkage can be detected. This study also expects that nanosheet wrapping could be effective over a longer time span by combination with conventional agarose embedding.