216 research outputs found
Nanoplatform Based on Vertical Nanographene
Self-organized graphite sheet nanostructures composed of graphene have been studied intensively. Carbon nanowalls and related sheet nanostructures are layered graphenes with open boundaries. The sheets form a self-supported network of wall structures with thicknesses in the range from a few nanometers to a few tens of nanometers, and with a high aspect ratio. The large surface area and sharp edges of carbon nanowalls could prove useful for a number of different applications. Fabrication techniques of carbon nanowalls and possible applications using carbon nanowalls as nanoplatform in the area of electrochemistry and tissue engineering have been described. Radical injection technique was successfully applied to fabricate straight and large-size monolithic carbon nanosheet. The structure of carbon nanowalls was controlled by changing the total pressure and input power. In addition, the structure of carbon nanowalls was modified by O2 plasma etching and H2O2 treatment. Using carbon nanowalls as platform would be the most promising and important application. Carbon nanowalls were used as electrode to detect several biomolecules. In addition, carbon nanowalls were oxidized by the surface treatment using atmospheric pressure plasma, and proteins such as bovine serum albumin were immobilized on these surface. Moreover, carbon nanowalls were used as scaffold for cell culturing. The dependence of the cell culturing rates and morphological changes of HeLa cells on carbon nanowall scaffolds with different densities and wettability were systematically investigated. Nanoplatform based on vertical nanographene offers great promise for providing a new class of nanostructured electrodes for electrochemical sensing, biosensing and energy conversion applications
Comparison of focal macular cone ERGs in complete-type congenital stationary night blindness and APB-treated monkeys
AbstractFocal macular cone electroretinograms (ERGs) and multifocal ERGs were recorded to study the macular function in patients with the complete-type of congenital stationary night blindness (cCSNB). The waveforms of the focal macular cone ERGs and the on- and off-responses of the multifocal ERGs in the cCSNB patients were similar to those recorded from monkey retinas treated with L-2 amino-4-phosphonobutyric acid (APB), suggesting that patients with cCSNB have a complete defect of the on-pathway even in the central retina. The results also demonstrated that there was a paradoxical positive response in the central retina of cCSNB patients, as compared to the negative full-field ERGs in the same subjects
Uniform Suspension of the Clustered Triamcinolone Acetonide Particle
Purpose. MaQaid (MaQ) is a new triamcinolone acetonide commercialised in Japan to visualize the vitreous. Because MaQ is preservative-free, it has a lower risk of ocular toxicities. However, since MaQ is only available as a powder, it needs suspenssion. Suspension does not always result uniformally, which causes poor visibility. This study reports a new MaQ suspension for better visibility. Methods. After medium addition to a MaQ vial, various methods were used. These included the use of (1) vortex mixer, (2) two syringes and a three-way stopcock, and (3) ultrasonic washer. We calculated suspended MaQ concentration (). To evaluate the reproducibility, we estimated the coefficient of variance (CV, ). We used this MaQ for pig eyes, and vitreous visualization was simulated. Subsequently, we used this MaQ suspension for humans.
Results.
MaQ suspensions were sucessfull, and the concentrations of single particles increased significantly (). The CV was 36.1% for the routine method and 9.03% ffor the new method. Administration of a suspended MaQ made it possible to clearly visualize the vitreous in both pig and human eyes. Conclusions.
We devised new techniques for uniformal MaQ suspension. These new methods can compensate for the MaQ disadvantages and ensure a safety surgery
Electroretinographic assessment of rod- and cone-mediated bipolar cell pathways using flicker stimuli in mice
Mouse full-field electroretinograms (ERGs) are dominated by responses of photoreceptors and depolarizing (ON-) bipolar cells, but not much of hyperpolarizing (OFF-) bipolar cells under conventional recording conditions. Here we investigate a novel ERG protocol in mice for functional assessment of the major ON-and OFF- bipolar cell pathways using flicker stimuli for a high luminance with varying frequency up to 30 Hz. Wild- type (WT) and functionally specific transgenic mice (Cnga3(-/-),no cone photoreceptor function;rho(-/-),no rod photoreceptor function;mGluR6(-/-),no ON-bipolar cell function) were examined. The Cnga3(-/-) flicker ERG was similar to the WT flicker ERG at very low stimulus frequencies, whereas ERGs were comparable between WT and rho(-/-) mice at 5 Hz and above. Between 5 and 15 Hz, ERGs in mGluR6(-/-) mice differed in configuration and amplitude from those in WT and rho(-/-) mice;in contrast, response amplitudes above 15 Hz were comparable among WT, rho(-/-) and mGluR6(-/-) mice. In summary, we found three frequency ranges with these conditions that are dominated by activity in the rod pathways (below 5 Hz),cone ON-pathway (between 5 and 15 Hz),and cone OFF-pathway (above 15 Hz) that enables a quick overview of the functionality of the major bipolar cell pathways
A Case of Focal Choroidal Excavation Development Associated with Multiple Evanescent White Dot Syndrome
Focal choroidal excavation (FCE) is described as an excavated lesion of the choroid that can be detected by optical coherence tomography (OCT). While the exact pathogenesis of FCE remains unclear, it has been proposed in some cases that there is an association with the inflammation in the outer retina. We present a case of FCE development that was detected by spectral domain OCT (SD-OCT) and found to be associated with multiple evanescent white dot syndrome (MEWDS). A 40-year-old Japanese woman was diagnosed with MEWDS based on multiple white dots observed from the posterior pole to the midperiphery, along with yellow granularity in the fovea. SD-OCT revealed separation between the retinal pigment epithelium (RPE) and Bruch’s membrane (BM) and discontinuations of the ellipsoid zone, RPE, and BM. At 4 weeks after onset, several of the white dots disappeared, the yellow granularity in the fovea became small, and we detected nonconforming choroidal excavation under the central fovea. The choroidal excavation gradually deepened and changed to a conforming pattern. These findings suggest that the degree of the impairment caused by inflammation and the plasticity of the BM and RPE complex may be associated with different types of acquired FCE
- …