Soft selective sweep near a gene that increases plant height in wheat.

Strong selection within a given population locally reduces genetic variability not only in the selected gene itself but also in neighbouring loci. This so-called hitch-hiking effect is related to the initial linkage disequilibrium between markers and the selected gene, and depends mainly on the number of copies of the beneficial allele at the start of the selection phase. Contrary to the classical case, in which selection acts on a single, newly arisen beneficial mutation, we considered selection from standing variation (soft selective sweeps) on a gene (Rht-B1) with a major effect on plant height, a selected trait in an experimental wheat population grown for 17 generations, and we documented the evolution of gene diversity and linkage disequilibrium near this gene. As expected, Rht-B1 was found to be under strong selection (s = 0.15) and its variation in frequency accounted for 15% of the total trait evolution. This led to a smaller genetic effective population size at Rht-B1 (N(eg) = 18) compared to the whole genome estimation (N(eg) = 167). When compared with expectations under genetic drift only, no significant decrease in gene diversity was found at the closest loci. We computed expected di-locus frequencies for any linked marker-Rht-B1 pair due to hitch-hiking effects. We found that hitch-hiking was expected to affect the two most closely linked loci, but expected reduction in gene diversity was not greater than that due to genetic drift, which was consistent with the observations. Such limited effect was attributed to the low level of linkage disequilibrium (0.16) estimated after parental intercrosses, together with a relatively high initial frequency of the gene. This situation is favourable to candidate gene approaches where small linkage disequilibrium around selected genes is expected.

Prognosis for vision in amblyopia after the loss of the good eye.

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.

Laparoscopic transabdominal pericardial window: new standard in the treatment of recurrent pericardial effusion complicated by cardiac tamponade.

Creation of a transabdominal transdiaphragmatic pericardial window for life-threatening recurrent pericardial effusion has proved to be a safe minimally invasive technique. By inducing adequate pericardial sac decompression while avoiding single-lung ventilation and thoracic drainage in severely ill patients, it provides anatomopathologic diagnosis and can direct further therapeutic measures. The transabdominal approach improves postoperative recovery dramatically by limiting postoperative pain and prevents sometimes invalidating intercostal neuralgia. Transabdominal pericardial sac fenestration should be part of the armamentarium used by every minimally invasive surgeon.

The adverse effects of corticosteroids in central serous chorioretinopathy.

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.

Optical coherence tomography of adult-onset vitelliform dystrophy.

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.

Malignant melanomas of the choroid and ruthenium applicators.

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.

[Oral lichen planus]. / Orale lichen planus.

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.

Inheritance of some Mendelian factors in intra- and interspecific crosses between Setaria italica and Setaria viridis.

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.

Indocyanine green angiography of choroidal tumors.

BACKGROUND: Fluorescein angiography (FA) has been widely used in the diagnostic evaluation of choroidal tumors. Indocyanine green angiography (ICG-A), which permits better visualization of choroidal vasculature than FA, has been recently introduced into clinical practice. Only few reports exist on the ICG-A characteristics of choroidal tumors. METHODS: The fluorescein and indocyanine green angiograms of 61 patients were assessed. These included 14 patients with choroidal nevi, 30 with malignant melanomas, 7 with suspected melanomas or atypical nevi, 5 with hemangiomas and 5 with metastases. RESULTS: The outline of pigmented tumors was more accurate on ICG-A than on FA. Characteristic patterns were seen in all intra-ocular tumors with ICG-A, so it was possible to distinguish hemangiomas from malignant lesions. Characteristic features of malignant melanomas include abnormal vascular pattern and marginal late dye leakage. None of the benign lesions showed these features. In suspected melanomas, the presence of abnormal choroidal vascular patterns and/or late dye leakage on ICG-A may indicate malignancy. CONCLUSION: The study suggests that ICG-A can yield additional information that is useful in differentiating amongst choroidal tumors. Better delineation of pigmented lesions with ICG-A allows more accurate treatment planning and follow-up.

Outcrossing and hybridization in wild and cultivated foxtail millets: consequences for the release of transgenic crops.

Outcrossing rates within the wild green foxtail, Setaria viridis, and the cultivated foxtail millet, S. italica, are very low. However, spontaneous interspecific hybridizations in the experimental garden occurred in both directions at rates ranging from 0.002% to 0.6% according to plant density and distance between parents. Offtypes found in farmers' fields where foxtail millet is cultivated were shown to have originated from such interspecific crosses. Differences in the EcoR1 patterns of chloroplast DNA between cultivated and wild plants indicated that reciprocal crosses do occur in the field. These findings indicate that even a largely selfing cultivated species may exchange genetic information with wild relatives at rates that may cause problems if transgenic cultivars are released.