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Polyploidization is a widespread process that results in the merger of two or more genomes in a common nucleus. To investigate modifications of gene expression occurring during allopolyploid formation, the Brassica napus allotetraploid model was chosen. Large-scale analyses of the proteome were conducted on two organs, the stem and root, so that >1600 polypeptides were screened. Comparative proteomics of synthetic B. napus and its homozygous diploid progenitors B. rapa and B. oleracea showed that very few proteins disappeared or appeared in the amphiploids (<1%), but a strikingly high number (25-38%) of polypeptides displayed quantitative nonadditive pattern. Nonstochastic gene expression repatterning was found since 99% of the detected variations were reproducible in four independently created amphiploids. More than 60% of proteins displayed a nonadditive pattern closer to the paternal parent B. rapa. Interspecific hybridization triggered the majority of the deviations (89%), whereas very few variations (approximately 3%) were associated with genome doubling and more significant alterations arose from selfing (approximately 9%). Some nonadditive proteins behaved similarly in both organs, while others exhibited contrasted behavior, showing rapid organ-specific regulation. B. napus formation was therefore correlated with immediate and directed nonadditive changes in gene expression, suggesting that the early steps of allopolyploidization repatterning are controlled by nonstochastic mechanisms.

Polyploidization is a major evolutionary process in eukaryotes. In plants, genetic and epigenetic changes occur rapidly after formation of allopolyploids. Hybridization, rather than genome doubling itself, is considered as the main cause for the resulting differential gene expression. We studied the consequences of genome doubling alone in an autopolyploid model, by comparing two-dimensional gel electrophoresis (2-DE) gels of haploid, diploid, and tetraploid Brassica oleracea cabbages. Two fully homozygous lines, HDEM and RC, as well as two organs, leaf and stem, were studied. For the 558 common spots found present in all the 29 2-DE gels of the experiment, inter-organ and -genotype differences were the major sources of the variation in protein amounts: 41 and 10-13%, respectively. HDEM leaf and stem proteomes were not significantly affected by the ploidy level, since no qualitative variation was detected and since the number of quantitative variations could be due to chance. For RC, no qualitative variations were observed, but a few spots were significantly variable in protein amount. However, the number of inter-ploidy variations was of the same range as the number of intra-ploidy variations. In conclusion, whatever the ploidy level, leaf and stem proteomes remained globally unchanged in both cabbage lines.

Purpose: To report the cross-sectional structure of the retina and choroid in eyes with adult-onset vitelliform macular dystrophy as obtained by optical coherence tomography (OCT)., Methods: Seven patients with adult-onset vitelliform macular dystrophy and one patient with Best disease were examined by fundoscopy, fluorescein and indocyanine green angiography and OCT. Three patients underwent also electro-oculography., Results: 1. Seven cases with adult-onset vitelliform macular dystrophy showed a well-circumscribed elevation of a highly reflective band, corresponding to the retinal pigment epithelium 2. In these 7 patients, the space below this band was inhomogeneous and moderately reflective. 3. Four cases out of 7 had a well defined posterior boundary. 4. The patient with Best disease disclosed a different aspect on OCT, although the contour of the lesion was similar to the others., Conclusion: Optical coherence tomography disclosed the structure of the vitelliform lesion in vivo and could be helpful for its pathological interpretation.

The purpose of this paper is to report on the possible deleterious effect of corticosteroids in central serous chorioretinopathy (CSCR). We will describe three patients in whom CSCR was induced or aggravated by corticosteroids. Despite multiple reports describing the onset of CSCR or aggravation of existing lesions with corticosteroids, they are still used by some ophthalmologists for the treatment of CSCR. Corticosteroids are also widely used for the treatment of a variety of diseases. Ophthalmologists should be aware that corticosteroids independently of the way of administration may cause this type of complication.

Oral lichen planus is a chronic inflammatory disease of adult onset. The etiopathology is based on a reaction against immunologically altered keratinocytes. There are variable forms of this condition, which at times make recognition difficult. Remissions are frequent. Associated oral carcinoma subsequent to the initial diagnosis of oral lichen planus is observed. Therefore all patients with oral lichen planus should be carefully evaluated and followed periodically.

The inheritance of seed coat color, pericarp color, polyphenoloxidase activity and bristle, glume, collar, and leaf-base anthocyanic colorations was investigated using intra- and interspecific crosses between Setaria italica and S. viridis. The results were compared to inheritance results obtained by previous authors. In most cases, the inheritance is simple (one or two loci) and data from different crosses (intra- and interspecific) and from different authors can be compared. Two sets of two characters were found to share common loci: the polyphenoloxidase locus is one of the loci responsible for seed coat color, and bristle and glume color are determined by the same two loci. The evolutionary significance of these results is discussed.

Fourty patients with a malignant melanoma of the choroid were treated with ruthenium applicators. Depending on the height of the tumour, the patients were divided into 3 groups. In the first group with a tumour height superior to 6 mm the results were poor as well from a functional point of view as considering tumour regression. In a second group with a tumour height between 5 and 6 mm the results were favourable concerning tumour regression, but only in 50% of the cases did the eye remain functional. The results in the third group with a tumour height between 2 and 5 mm were satisfactory. Tumour regression was obtained in 96% of the eyes; 86% of the eyes remained functional. Tumour related death (7.5%) was not correlated with initial height of the tumour at the time of diagnosis.

Two hundred three cases of unilateral amblyopia with the loss of the good eye included 59 taken from literature and 144 obtained from a questionnaire sent to ophthalmologists. The improvement noted in both sources was quite different: 47.5% v 28.5%. Because the cases from the questionnaire constituted a much more random selection than those from the literature, the former serve as a basis for discussion and conclusions. In 17.4% of the cases improvement was obtained without treatment. This result is closely linked to the existence of foveal fixation (93.7%). In 11.1% of the cases, the improvement was obtained with pleoptic treatment. The important prognostic factors were the existence of foveal fixation and the loss of the good eye. Pleoptic treatment was valuable in our sample, especially for patients with eccentric fixation.