The earliest morphological events associated with eye development are the formation of the optic pit and optic vesicles from the walls of the neural tube destined to become the forebrain. Invagination of the optic vesicles results in the formation of the double-walled optic cup. The outer layer of the optic cup differentiates into the pigment epithelium, the iris and the ciliary body epithelium, whereas the thicker inner layer forms the neural retina. Early in development, the retina consists of neuroectodermal precursor cells that have the potential of differentiating into six major classes of neuronal cells (ganglion, amacrine, bipolar, horizontal, cone photoreceptors, rod photoreceptors) as well as Müller glial cells. The first cells to differentiate in the vertebrate retina are the ganglion cells, closely followed by amacrine cells, photoreceptors and horizontal cells, then bipolar cells and Müller glia (Prada et al. 1991;Cepko et al. 1996). The orderly appearance and differentiation of the different classes of cells in the developing retina results in the formation of three nuclear layers (ganglion, inner nuclear, outer nuclear) separated by two synaptic layers (inner and outer plexiform).Ganglion cells and photoreceptors are found in the ganglion cell layer and outer nuclear layer, respectively, with the four remaining cell types (horizontal, bipolar, Müller and amacrine) forming the inner nuclear layer.Important insights into the molecular mechanisms underlying retinal differentiation have been gained through analysis of retina-specific or retina-enriched transcription factors. For example, the homeobox gene, Otx2, has been Address correspondence and reprint requests to Roseline Godbout, Department of Oncology, Cross Cancer Institute, 11560 University Avenue, Edmonton, AB T6G 1Z2, Canada. E-mail: rgodbout@ualberta.caAbbreviations used: CHX10, Ceh-10 homeodomain containing homolog; CRX, cone-rod homeobox; GS, glutamine synthetase; GST, glutathione S-transferase; IRBP, interphotoreceptor retinoid-binding protein; OTX2, orthodenticle homeobox 2; PDEB, phosphodiesterase b subunit; PKCa, protein kinase C alpha; RPE, retinal pigmented epithelium; SDS, sodium dodecyl sulfate. AbstractThe histogenesis of retinoblastoma tumors remains controversial, with the cell-of-origin variably proposed to be an uncommitted retinal progenitor cell, a bipotent committed cell, or a cell committed to a specific lineage. Here, we examine the expression of two members of the orthodenticle family implicated in photoreceptor and bipolar cell differentiation, conerod homeobox, CRX, and orthodenticle homeobox 2, OTX2, in normal human retina, retinoblastoma cell lines and retinoblastoma tumors. We show that CRX and OTX2 have distinct expression profiles in the developing human retina, with CRX first expressed in proliferating cells and cells committed to the bipolar lineage, and OTX2 first appearing in the photoreceptor lineage. In the mature retina, CRX levels are highest in photoreceptor cells whereas OTX2 is preferentially found in b...

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Health issues in elderly individuals are often complex and tend to lead to chronic diseases; such issues can be due to a decline in fitness resulting from lack of physical activity. Aqua exercise and burdock are positive effects on cardiovascular disease and vascular health. This study investigated the changes due to aqua exercise and burdock extract intake in senior fitness, prostaglandin I2 (PGI2), and thromboxane A2 (TXA2) in elderly women. Forty elderly women (65–80 years) volunteered for this study. After baseline measurements, participants were randomized into control (n = 8), aqua exercise (n = 11), aqua exercise and burdock extract intake combination (n = 11), and burdock extract intake groups (n = 10). The variables of senior fitness tests, PGI2 and TXA2 were measured in all participants before and after the 12-week study. Blood collections were carried out at the beginning- and the end of aqua exercise training. Muscular strength, endurance, flexibility, and cardiorespiratory endurance of aqua exercise and burdock extract intake group at post-test significantly increased compared to pre-test (p<0.05). There were no significant differences in PGI2 and TXA2 between pre- and post-training programs. In conclusion, our findings indicated that the aqua exercise and burdock extract intake improves senior fitness factors in elderly Korean women. Also, the program participation led to a balance between PGI2 and TXA2. Additionally, burdock extract intake may be useful in vascular health by playing a secondary role in disease prevention and health promotion.

The microtubule cytoskeleton is composed of α-tubulin and β-tubulin heterodimers, and it serves to regulate the shape, motility, and division of a cell. Post-translational modifications including acetylation are closely associated with the functional aspects of the microtubule, involving in a number of pathological diseases. However, the role of microtubule acetylation in acute kidney injury (AKI) and progression of AKI to chronic kidney disease have yet to be understood. In this study, ischemia/reperfusion (I/R), a major cause of AKI, resulted in deacetylation of the microtubules with a decrease in α-tubulin acetyltransferase 1 (α-TAT1). Paclitaxel (taxol), an agent that stabilizes microtubules by tubulin acetylation, treatment during the recovery phase following I/R injury inhibited tubular cell proliferation, impaired renal functional recovery, and worsened fibrosis. Taxol induced α-tubulin acetylation and post-I/R cell cycle arrest. Taxol aggregated the microtubule in the cytoplasm, resulting in suppression of microtubule dynamics. Our studies have demonstrated for the first time that I/R induced deacetylation of the microtubules, and that inhibition of microtubule dynamics retarded repair of injured tubular epithelial cells leading to an acceleration of fibrosis. This suggests that microtubule dynamics plays an important role in the processes of repair and fibrosis after AKI.

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Infectious diseases and the deaths caused due to contact with germ-contaminated surfaces are severe problems worldwide. Antibacterial materials based on silver nanowires (AgNWs) have a structural advantage when addressing this issue; this is because agglomeration is minimized when nanowires are fabricated into a film. Therefore, employing AgNWs for antimicrobial applications has garnered continuous interest, and increased research for further improvements has been observed. In this study, a AgNW film was fabricated onto glass by spin-coating and then subjected to surface irradiation up to a dose of 1200 kGy, using a low-energy electron beam (e-beam). This “e-beam” irradiation changed the surface morphology and chemical composition; consequently, this improved the performance of the film. The generation of a silver oxide (Ag2O and AgO) outer layer was identified over the AgNWs by X-ray photoelectron spectroscopy (XPS). The antibacterial test corresponding to a contact time of 1 h revealed that the e-beam irradiation increased the antibacterial activity in the log reduction from 1.2 to 1.4 for Staphylococcus aureus and from 1.5 to 3.7 for Escherichia coli. Based on the experimental results and the known antibacterial mechanisms of silver (Ag) nanospecies, we discuss the method by which the antibacterial performance of the AgNW film was improved via the e-beam irradiation. This work provides a simple and swift method to functionally enhance the AgNW antibacterial film via e-beam irradiation.

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