Retinal images of an infant with type 1 ROP (case no:8).

<p>(A,B) Zone II stage 3 ROP with plus disease before treatment. (C,D) Plus disease and ROP regressed 1 week following laser treatment.</p

Demographic data and refractive outcomes of laser and IVB treated infants.

<p>Demographic data and refractive outcomes of laser and IVB treated infants.</p

Risk factors of the study population (N = 36).

<p>Risk factors of the study population (N = 36).</p

Retinal images of an infant with APROP (case no:29).

<p>(A) Intensive shunt vessels with plus disease indicate Zone I APROP. (B) A dramatic response to IVB injection with regression of plus disease and resolution of shunt vessels 1 week following treatment.</p

Demographic data and clinical characteristics of the infants.

<p>Demographic data and clinical characteristics of the infants.</p

Evaluation of <i>Factor V Leiden, Prothrombin G20210A, MTHFR C677T</i> and <i>MTHFR A1298C</i> gene polymorphisms in retinopathy of prematurity in a Turkish cohort

<p><i>Background</i>: To assess <i>Factor V Leiden (FVL)</i> (rs6025), <i>Prothrombin G20210A</i> (rs1799963), <i>MTHFR C677T</i> (rs1801133), and <i>MTHFR A1298C</i> (rs1801131) gene mutations as risk factors in the development of retinopathy of prematurity (ROP).</p> <p><i>Materials and methods</i>: A total of 105 children were included in this cross-sectional study. Patients were divided into two groups. The study group consisted of 55 infants with a history of ROP and the control group comprised 50 healthy infants with term birth. All subjects were screened for the presence of certain mutations (<i>FVL, Prothrombin G20210A, MTHFR C677T</i> and <i>MTHFR A1298C</i>) by Real-Time PCR at 1 year of age.</p> <p><i>Results</i>: The mean gestational age (GA) and birth weight (BW) of the study group were, 28.65 ± 2.85 weeks and 1171 ± 385.74 g, respectively. There were no significant differences of genotype and allele frequency of <i>Prothrombin G20210A, MTHFR A1298C</i> and <i>MTHFR C677T</i> between the study and control groups (<i>p</i> > 0.05). Eight children (14.5 %) had heterozygous and one child (1.8%) had homozygous <i>FVL</i> mutation in the study group. One child (2%) in the control group had heterozygous <i>FVL</i> mutation. There was statistically significant differences of <i>FVL</i> allele and genotype frequencies between the groups (<i>p</i> < 0.05).</p> <p><i>Conclusions</i>: The prevalence of <i>FVL</i> polymorphism (16.3 %) was higher in ROP patients than control subjects in this Turkish cohort. We suggest a possible association of <i>FVL</i> mutation with ROP at the end of the study.</p

Probing the Oxygen Reduction Reaction Active Sites over Nitrogen-Doped Carbon Nanostructures (CN_<i>x</i>) in Acidic Media Using Phosphate Anion

To probe the active sites of nitrogen-doped carbon nanostructures (CN_<i>x</i>), the effect of dihydrogen phosphate (H₂PO₄^–) anion on their oxygen reduction reaction (ORR) performance was investigated by adding increasing concentrations of phosphoric acid in half-cell measurements. A linear decrease in specific kinetic current at 0.7 V was noted with increasing phosphate anion concentration. It was also found that the adsorption of phosphate species on CN_<i>x</i> was strong and the corresponding ORR activity was not recovered when the catalyst was reintroduced to a fresh HClO₄ solution. Trends similar to those noted upon addition of H₃PO₄ to the half-cell were observed when CN_<i>x</i> catalysts were soaked in phosphoric acid. Adsorption of dihydrogen phosphate ions on the surface of CN_<i>x</i> exposed to phosphoric acid was verified by transmission infrared (IR) and Raman spectroscopy as well as X-ray photoelectron spectroscopy (XPS). XPS results also showed a decrease in the surface concentration of pyridinic-N species accompanied by an increase of equal magnitude in the surface fraction of quaternary-N species, which would include the pyridinic-NH sites. A linear correlation was observed between the loss in pyridinic-N site density and that in ORR activity. The observed poisoning phenomenon is consistent with the two possible active site models, i.e., pyridinic-N sites, which would be rendered inactive by protonation, or the C sites neighboring pyridinic-N species. These latter species would be poisoned by a site blocking effect if they strongly adsorb the phosphate ions. Strong adsorption of negatively charged phosphate ions on neighboring C atoms would also stabilize the pyridinic-NH sites. By identifying a poison that can be used as a probe, this study provides a first step toward identification and quantification of active sites in CN_<i>x</i> catalysts