Steric Interaction of Polyglycerol-Functionalized Detonation Nanodiamonds.

Detonation nanodiamonds have found numerous potential applications in a diverse array of fields such as biomedical imaging and drug delivery. Here, we systematically characterized non-functionalized and polyglycerol-functionalized detonation nanodiamond particles (DNPs) dispersed in aqueous suspensions at different ionic strengths (∼1.0 × 10 to 1.

Diamond Colloidal Probe Force Spectroscopy.

Diamond is a highly attractive coating material as it is characterized by a wide optical transparency window, a high thermal conductivity, and an extraordinary robustness due to its mechanical properties and its chemical inertness. In particular, the latter has aroused a great deal of interest for scanning probe microscopy applications in recent years. In this study, we present a novel method for the fabrication of atomic force microscopy (AFM) probes for force spectroscopy using robust diamond-coated spheres, i.

Expression of Two Classes of Pax6 Transcripts in Reprogramming Retinal Pigment Epithelium Cells of the Adult Newt.

The adult newt has the remarkable ability to regenerate a functional retina from retinal pigment epithelium (RPE) cells, even when the neural retina (NR) is completely lost from the eye. In this system, RPE cells are reprogrammed into a unique state of multipotent cells, named RPESCs, in an early phase of retinal regeneration. However, the signals that trigger reprogramming remain unknown.

Electrostatic Self-Assembly of Diamond Nanoparticles onto Al- and N-Polar Sputtered Aluminum Nitride Surfaces.

Electrostatic self-assembly of diamond nanoparticles (DNPs) onto substrate surfaces (so-called nanodiamond seeding) is a notable technique, enabling chemical vapor deposition (CVD) of nanocrystalline diamond thin films on non-diamond substrates. In this study, we examine this technique onto differently polarized (either Al- or N-polar) -axis oriented sputtered aluminum nitride (AlN) film surfaces. This investigation shows that Al-polar films, as compared to N-polar ones, obtain DNPs with higher density and more homogeneously on their surfaces.

Appropriate salt concentration of nanodiamond colloids for electrostatic self-assembly seeding of monosized individual diamond nanoparticles on silicon dioxide surfaces.

Monosized (∼4 nm) diamond nanoparticles arranged on substrate surfaces are exciting candidates for single-photon sources and nucleation sites for ultrathin nanocrystalline diamond film growth. The most commonly used technique to obtain substrate-supported diamond nanoparticles is electrostatic self-assembly seeding using nanodiamond colloidal suspensions. Currently, monodisperse nanodiamond colloids, which have a narrow distribution of particle sizes centering on the core particle size (∼4 nm), are available for the seeding technique on different substrate materials such as Si, SiO2, Cu, and AlN.

MEK-ERK signaling in adult newt retinal pigment epithelium cells is strengthened immediately after surgical induction of retinal regeneration.

Adult newt retinal pigment epithelium (RPE) cells are mitotically quiescent in the physiological condition, but upon a traumatic injury of the neural retina (NR) they re-enter the cell-cycle and eventually regenerate the missing NR. Here, to understand the mechanism underlying the cell-cycle re-entry of RPE cells following NR injury, we first investigated changes in MEK-ERK signaling activity in RPE cells upon removal of the NR (retinectomy) from the eye of living animals, and found that ERK-mediated signaling activity is elevated quickly (in 30 min) upon retinectomy. In addition, we found, in in vitro analyses, that immediate early activation of MEK-ERK signaling may occur in RPE cells upon NR injury, intensifying the MEK-ERK signaling itself through up-regulation of the expression of constituent molecules in the pathway, and that 1-h blockade of such early MEK-ERK signaling interferes with the cell-cycle re-entry, which occurs 5-10 days later.

Metamorphosis inhibition: an alternative rearing protocol for the newt, Cynops pyrrhogaster.

The newt is an indispensable model animal, of particular utility for regeneration studies. Recently, a high-throughput transgenic protocol was established for the Japanese common newt, Cynops pyrrhogaster. For studies of regeneration, metamorphosed animals may be favorable; however, for this species, there is no efficient protocol for maintaining juveniles after metamorphosis in the laboratory.

MEK-ERK and heparin-susceptible signaling pathways are involved in cell-cycle entry of the wound edge retinal pigment epithelium cells in the adult newt.

The onset mechanism of proliferation in mitotically quiescent retinal pigment epithelium (RPE) cells is still obscure in humans and newts, although it can be a clinical target for manipulating both retinal diseases and regeneration. To address this issue, we investigated factors or signaling pathways involved in the first cell-cycle entry of RPE cells upon retinal injury using a newt retina-less eye-cup culture system in which the cells around the wound edge of the RPE exclusively enter the cell cycle. We found that MEK-ERK signaling is necessary for their cell-cycle entry, and signaling pathways whose activities can be modulated by heparin, such as Wnt-, Shh-, and thrombin-mediated pathways, are capable of regulating the cell-cycle entry.

Musashi-1, an RNA-binding protein, is indispensable for survival of photoreceptors.

Musashi-1 (Msi1), an RNA-binding protein (RBP), has been postulated to play important roles in the maintenance of the stem-cell state, differentiation, and tumorigenesis. However, the expression and function of Msi1 in differentiated cells remain obscure. Here we show that Msi1 is expressed in mature photoreceptors and retinal pigment epithelium (RPE) cells, and is indispensable for the survival of photoreceptors.