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OBJECTIVES The retinal vessel analyzer (RVA) offers the unique opportunity of noninvasive online measurements of retinal vessel diameters. Breathing 100% oxygen is used to test vessel contractility of retinal arterioles in different stages of diabetic retinopathy (DR). METHODS After a 3-min baseline measurement 40 patients with diabetes were exposed to 100% oxygen breathing for a 5-min period. The diameter of a retinal arteriole was measured with the RVA continuously during this time. Subjects were divided into four groups according to different stages of DR. Group I: no RD; group II: mild/moderate RD; group III: moderate/severe nonproliferative RD with laser treatment; group IV: proliferative RD with laser treatment. RESULTS Group I (n=12) demonstrated a vasoconstriction of 6.2% (+/-4.0). In group II (n=8) 6.1% (+/-2.8) and in group III (n=8) 6.6% (+/-4.1) vasoconstriction was found. Group IV (n=12) presented a vasodilatation of +2.5% (+/-4,7). CONCLUSION No significant differences could be found in the vasoreaction to 100% oxygen breathing in different stages of nonproliferative RD. However, a significant reduction could be demonstrated in proliferative DR with this method.

Sperm typing was used to measure recombination fractions among pseudoautosomal markers and the beginning of the X/Y-specific sequences located at the pseudoautosomal boundary. These experiments included primer-extension preamplification and PCR followed by allele typing using gel electrophoresis. A newly developed data-analysis program allowed the construction of the first multipoint-linkage sperm-typing map, using results obtained on seven loci from three individuals. The large sample size not only confirmed the increased recombination activity of the pseudoautosomal region but allowed an estimate of interference of recombination to be made. The coefficient of coincidence was calculated to be .26 over a physical distance of only approximately 1,800 kb. The observation of a few sperm presumably resulting from double recombination argues that more than one crossover event can occur in this region during male meiosis.

Purpose: Circulating estrogen levels are relevant in glaucoma phenotypic traits. We assessed the association between an estrogen metabolism single nucleotide polymorphism (SNP) panel in relation to primary open angle glaucoma (POAG), accounting for gender. Methods: We included 3,108 POAG cases and 3,430 controls of both genders from the Glaucoma Genes and Environment (GLAUGEN) study and the National Eye Institute Glaucoma Human Genetics Collaboration (NEIGHBOR) consortium genotyped on the Illumina 660W-Quad platform. We assessed the relation between the SNP panels representative of estrogen metabolism and POAG using pathway-and gene-based approaches with the Pathway Analysis by Randomization Incorporating Structure (PARIS) software. PARIS executes a permutation algorithm to assess statistical significance relative to the pathways and genes of comparable genetic architecture. These analyses were performed using the metaanalyzed results from the GLAUGEN and NEIGHBOR data sets. We evaluated POAG overall as well as two subtypes of POAG defined as intraocular pressure (IOP) ≥22mmHg (high-pressure glaucoma [HPG]) or IOP 0.99). Among women, gene-based analyses revealed that the catechol-O-methyltransferase gene showed strong associations with HTG (permuted gene p≤0.001) and NPG (permuted gene p=0.01). Conclusions: The estrogen SNP pathway was associated with POAG among women. © 2013 Molecular Vision.