92 resultados para MILKY SPOTS
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Behavioral and physiological responses to unpredictable changes in environmental conditions are, in part, mediated by glucocorticoids (corticosterone in birds). In polymorphic species, individuals of the same sex and age display different heritable melanin-based color morphs, associated with physiological and reproductive parameters and possibly alternative strategies to cope with variation in environmental conditions. We examined whether the role of corticosterone in resolving the trade-off between self-maintenance and reproductive activities covaries with the size of melanin-based spots displayed on the ventral body side of male barn owls. Administration of corticosterone to simulate physiological stress in males revealed pronounced changes in their food-provisioning rates to nestlings compared to control males. Corticosterone-treated males with small eumelanic spots reduced nestling provisioning rates as compared to controls, and also to a greater degree than did corticosterone-treated males with large spots. Large-spotted males generally exhibited lower parental provisioning and appear insensitive to exogenous corticosterone suggesting that the size of the black spots on the breast feathers predicts the ability to cope with stressful situations. The reduced provisioning rate of corticosterone-treated males caused a temporary reduction in nestling growth rates but, did not affect fledgling success. This suggests that moderately elevated corticosterone levels are not inhibitory to current reproduction but rather trigger behavioral responses to maximize lifetime reproductive success.
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Sex-dependent selection can help maintain sexual dimorphism. When the magnitude of selection exerted on a heritable sex trait differs between the sexes, it may prevent each sex to reach its phenotypic optimum. As a consequence, the benefit of expressing a sex trait to a given value may differ between males and females favouring sex-specific adaptations associated with different values of a sex trait. The level of metabolites regulated by genes that are under sex-dependent selection may therefore covary with the degree of ornamentation differently in the two sexes. We investigated this prediction in the barn owl, a species in which females display on average larger black spots on the plumage than males, a heritable ornament. This melanin-based colour trait is strongly selected in females and weakly counter-selected in males indicating sex-dependent selection. In nestling barn owls, we found that daily variation in baseline corticosterone levels, a key hormone that mediates life history trade-offs, covaries with spot diameter displayed by their biological parents. When their mother displayed larger spots, nestlings had lower corticosterone levels in the morning and higher levels in the evening, whereas the opposite pattern was found with the size of paternal spots. Our study suggests a link between daily regulation of glucocorticoids and sex-dependent selection exerted on sexually dimorphic melanin-based ornaments.
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UNIVERSITE DE LAUSANNE - FACULTE DE BIOLOGIE ET DE MEDECINE Médecine Ophtalmologie Etude clinique et angiographique lors de la Syphilis Oculaire THESE préparée sous la direction du Docteur Yan Guex-Crosier et présentée à la Faculté de biologie et de médecine de l'Université de Lausanne pour l'obtention du grade de DOCTEUR EN MEDECINE par Konstantinos BALASKAS Médecin diplômé de la Grèce Originaire d'Athènes (Grèce) ι Lausanne 2012 Une recrudescence des cas de syphilis a été observée ces dernières années. Son diagnostic clinique reste particulièrement difficile en l'absence de signe pathognomonique. Sur le plan oculaire elle présente un vaste spectre de manifestations diverses lui ayant valu le surnom de « la grande imitatrice ». Sa rareté et son hétérogénéité ont empêché l'identification et la vérification statistique des facteurs liés à un pronostic défavorable. Le but de cette étude a été d'explorer les paramètres cliniques et para-cliniques déterminant la sévérité et influençant l'évolution de la maladie. Ce travail comprend deux volets, la première partie intitulée : «Analysis of significant factors influencing visual acuity in ocular syphilis» publiée dans le British Journal of Ophthalmology a démontré qu'une mauvaise acuité visuelle initiale est associée de façon statistiquement significative à la sévérité de l'amputation du champ visuel, à la présence d'un oedème maculaire ou d'une neuropathie optique. Une amélioration de l'acuité visuelle grâce au traitement antibiotique est associée à la présence d'une vasculite (visible à l'angiographie fluorescéinique), d'une neurosyphilis ou d'une uvéite antérieure. Une récidive inflammatoire est fortement associée à une durée prolongée des symptômes avant l'introduction du traitement et à la présence de douleur comme signe d'appel. L'utilité clinique principale de ces résultats statistiques permet de conclure que les formes inflammatoires sévères associées à la triade (vasculite, neurosyphilis et uvéite antérieure) constituent un phénomène réversible pour autant qu'un traitement précoce et adéquat ait été introduit. Le deuxième volet de l'étude analyse les manifestations angiographiques (à la fluorescéine (AF) et au vert d'indocyanine (AICG)) de la syphilis oculaire et a été publié dans le journal du Graefes Archives of Clinical and Experimental Ophthalmology sous le titre suivant : "Fluorescein and indocyanine-green angiography in ocular syphilis: an exploratory study". Des associations faibles ont été démontrées entre la présence d'une vasculite lors de AF et d'une uvéite antérieure, d'une hyalite et d'un âge plus jeune. Une association forte est identifiée entre la présence des «dark dots» sur l'AICG et d'une uvéite antérieure ainsi qu'entre la présence des «hot spots» sur l'AICG et d'une durée prolongée des symptômes. Les conclusions d'importance clinique significative lors de la syphilis oculaire sont que les « dark dots » ou hypofluorescences en AICG évoquent la présence d'une atteinte inflammatoire oculaire sévère et que les « hot spots » ou hyperfluorescences en AICG sont significatifs d'une atteinte chronique. Cette étude contribue à modifier les attitudes cliniques lors de la syphilis oculaire surtout en ce qui concerne l'urgence à traiter afin d'assurer une récupération optimale. Elle aide aussi à redéfinir le rôle de l'angiographie dans la syphilis oculaire pour déterminer la sévérité, la durée de la maladie ainsi que le pronostic visuel.
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Identifying the factors that mediate covariation between an ornament and other phenotypic attributes is important to determine the signaling function of ornaments. Sign and magnitude of a covariation may vary across environments if the expression of the ornament or of its linked genes regulating correlated phenotypes is condition-dependent. I investigated in the barn owl Tyto alba whether sign and magnitude of covariation between body mass and two heritable melanin-based plumage ornaments change with food supply, along the reproductive cycle and from the morning to the evening. Using a dataset of 1,848 measurements of body mass in 336 breeding females, I found that females displaying large black spots were heavier than conspecifics with smaller spots in the afternoon (i.e., a long time after the last feeding) but not in the morning (i.e., a short time after the last feeding). This is consistent with the recently proposed hypothesis that eumelanin-based ornaments are associated with the ability to maintain energy balance between food intake and energy expenditure. Thus, covariation between melanin-based coloration and body mass can be detected only under specific conditions potentially explaining why it has been reported in only ten out of 28 vertebrate species. The proposition that ornamented individuals achieve a higher fitness than drab conspecifics only in specific environments should be tested for other ornaments.
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Methylene blue (MB) and light are used for virus inactivation of plasma for transfusion. However, the presence of MB has been the subject of concern, and efforts have been made to efficiently remove the dye after photo-treatment. For this study, plasma was collected by apheresis from 10 donors (group A), then treated using the MacoPharma THERAFLEX procedure (MB; 1 microM, and light exposure; 180 J/cm(2)) (group B), and finally filtered in order to remove the dye (group C). Proteins were analyzed by two-dimensional electrophoresis, and peptides showing modifications were characterized by mass spectrometry. Clottable and antigenic fibrinogen levels, as well as fibrin polymerization time were measured. Analyses of the gels focused on a region corresponding to pI between 4.5 and 6.5, and M(r) from 7000 to 58 000. In this area, 387 +/- 47 spots matched, and four of these spots presented significant modifications. They corresponded to changes of the gamma-chain of fibrinogen, of transthyretin, and of apolipoprotein A-I, respectively. A decrease of clottable fibrinogen and a prolongation of fibrin polymerization time were observed in groups B and C. Removal of MB by filtration was not responsible for additional protein alterations. The effect of over-treatment of plasma by very high concentrations of MB (50 microM) in association with prolonged light exposure (3 h) was also analyzed, and showed complex alterations of most of the plasma proteins, including fibrinogen gamma-chain, transthyretin, and apolipoprotein A-I. Our data indicates that MB treatment at high concentration and prolonged illumination severely injure plasma proteins. By contrast, at the MB concentration used to inactivate viruses, damages are apparently very restricted.
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In adipocytes and muscle cells, the GLUT4 glucose transporter isoform is present in intracellular vesicles which continuously recycle between an intracytoplasmic location and the plasma membrane. It is not clear whether the GLUT4-vesicles represent a specific kind of vesicle or resemble typical secretory granules or synaptic-like microvesicles. To approach this question, we expressed GLUT4 in the beta cell line RINm5F and determined its intracellular localization by subcellular fractionation and by immunofluorescence and immunoelectron microscopy. GLUT4 was not found in insulin granules but was associated with a subpopulation of smooth-surface vesicles present in the trans-Golgi region and in vesicular structures adjacent to the plasma membrane. In the trans-Golgi region, GLUT4 did not colocalize with synaptophysin or TGN38. Incubation of the cells with horseradish peroxidase (HRP) led to colocalization of HRP and GLUT4 in some endosomal structures adjacent to the plasma membrane and in occasional trans-Golgi region vesicles. When cells were incubated in the presence of Bafilomycin A, analysis by confocal microscopy revealed GLUT4 in numerous large spots present throughout the cytoplasm, many of which costained for TGN38 and synaptophysin. By immunoelectron microscopy, numerous endosomes were observed which stained strongly for GLUT4. Together our data demonstrate that ectopic expression of GLUT4 in insulinoma cells reveals the presence of a subset of vesicular structures distinct from synaptic-like vesicles and insulin secretory granules. Furthermore, they indicate that GLUT4 constitutively recycles between the plasma membrane and its intracellular location by an endocytic route also taken by TGN38 and synaptophysin.
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Aims: The HR-NBL1 Study of the European SIOP Neuroblastoma Group (SIOPEN) randomised two high dose regimens to learn about potential superiority and toxicity profiles.Patients and Methods: At interim analysis 1483 high risk neuroblastoma patients (893 males) were included since 2002 with either INSS stage 4 disease (1383 pts) above 1 year, or as infants (59 pts) and stage 2&3 of any age (145 pts) with MYCN amplification. The median age at diagnosis was 2.9 years (1 month-19.9 years) with a median follow up of 3 years. Response eligibility criteria prior randomisation after Rapid Cojec Induction (J Clin Oncol, 2010) ± 2 courses of TVD (Cancer, 2003) included complete bone marrow remission and at least partial response at skeletal sites with no more than 3, but improved mIBG positive spots and a PBSC harvest of at least 3x10E6 CD34/kgBW. The randomised regimens were BuMel [busulfan oral till 2006, 4x150mg/m² in 4 ED; or intravenous use according to body weight as licenced thereafter; melphalan 140mg/m²/day) and CEM [carboplatinum ctn. infusion (4x AUC 4.1mg/ml.min/day, etoposid ctn. infusion (4x 338mg/m²/day or [4x 200mg/m²/day]*, melphalan (3x70mg/m²/day; 3x60mg/m²/day*;*reduced dosis if GFR< 100ml/min/1.73m²). Supportive care followed institutional guidelines. VOD prophylaxis included ursadiol, but randomised patients were not eligible for the prophylactic defibrotide trial. Local control included surgery and radiotherapy of 21Gy.Results: Of 1483 patients, 584 were being randomised for the high dose question at data lock. A significant difference in event free survival (3-year EFS 49% vs. 33%, p<0.001) and overall survival (3-year OS 61% vs. 48%, p=0.003) favouring the BuMel regimen over the CEM regimen was demonstrated. The relapse/progression rate was significantly higher after CEM (0.60±0.03) than after BuMel (0.48±0.03)(p<0.001). Toxicity data had reached 80% completeness at last analysis. The severe toxicity rate up to day 100 (ICU and toxic deaths) was below 10%, but was significantly higher for CEM (p= 0.014). The acute toxic death rate was 3% for BuMel and 5% for CEM (NS). The acute HDT toxicity profile favours the BuMel regimen in spite of a total VOD incidence of 18% (grade 3:5%).Conclusions: The Peto rule of P<0.001 at interim analysis on the primary endpoint, EFS was met. Hence randomization was stopped with BuMel as recommended standard treatment in the HR-NBl1/SIOPEN trial which is still accruing for the randomised immunotherapy question.
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Sexual selection theory predicts that males advertise quality by displaying extravagant ornaments. By contrast, whether phenotypic variation in females has a signalling function remains an open question. Here, to our knowledge, we provide the first evidence that a female plumage trait can signal fluctuating asymmetry in the offspring. We experimentally demonstrate in wild barn owls (Tyto alba) that the extent to which females display black spots on their plumage does not only signal offspring parasite resistance as shown in a previous study but also developmental homeostasis in the offspring. A greater number of spotted females produced offspring that had more symmetrical feathers during the period of growth. Males, that pair non-randomly with respect to female plumage spottiness therefore appear to gain substantial benefits by mating with heavily spotted females. Genetic variation in plumage spottiness is nevertheless maintained as the covariation between offspring body mass and mother plumage spottiness varies annually depending on environmental conditions.
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RESUME Les bétalaïnes sont des pigments chromo-alcaloïdes violets et jaunes présents dans les plantes appartenant à l'ordre des Caryophyllales et dans les champignons des genres Amanita et Hygrocybe. Leur courte voie de biosynthèse est élucidée chimiquement depuis de nombreuses années, mais les enzymes impliquées dans cette biosynthèse chez les plantes ne sont toujours pas caractérisées. L'enzyme de la DOPA-dioxygénase d' Amanita muscaria a été identifiée (Girod et Zryd, 1991a), mais de nombreuses tentatives d'isolation d'un homologue chez les plantes ont échoué. Afin d'isoler les gènes spécifiques des bétalaïnes chez les plantes, nous avons construit des banques soustraites d'ADNc à partir d'ARN total de pétales immatures de Portulaca grandiflora (Pg) de génotypes jaunes et blancs, respectivement violets et blancs. Les clones couleur- spécifiques ont été détectés en premier par analyse Northem du RNA de pétales blancs et colorés. Les candidats positifs ont alors été soumis à une analyse de transcription au niveau des tiges colorées, vertes et des feuilles, afin d'établir leur expression spécifique. Deux ARNs messagers complets ont une expression corrélée avec l'accumulation des bétalaïnes dans les tissus. Le premier de ces clones, A.16, code pour une oxydase de l'acyl-Coenzyme A (ACX) putative, mais le domaine de liaison du FAD essentiel pour l'activité d'ACX est absent. Toutes nos tentatives pour démontrer sa fonction ont échoué. Le rôle de cette protéine dans la voie de synthèse des bétalaïnes reste inconnu. Le deuxième de ces clones spécifique aux bétalaïnes, L.6 (isolé par Zaiko, 2000), a été renommé DODA en raison de son homologie avec le domaine LigB (pfam02900) d'une 4,5-dioxygénase extradiol bactérienne. DODA a été identifié in silico comme une dioxygénase extradiol en raison de la conservation stricte, au niveau de sa séquence peptidique, des résidus catalytiques de LigB et de ceux liant le cofacteur fer. Une analyse de transfert Southem a montré que ce gène est unique dans Pg. L'expression transitoire de DODA par transformation biolistique dans des pétales blancs de Pg a produit des taches violettes ou jaunes dans des cellules transformées. Une analyse HPLC de ces taches a démontré leur identité avec les bétalaïnes présentes naturellement dans les pétales violets et jaunes de Pg, confirmant ainsi la complémentation par le gène Pg DODA de l'allèle récessif cc présent dans les pétales blancs de Pg. Des homologues de DODA (DOPA-dioxygénase) ont été identifiés dans de nombreuses espèces de plantes, y compris dans celles sans bétalaïne. L'alignement de ces homologues a permis l'identification d'un motif spécifique aux bétalaïnes à côté d'une histidine catalytique conservée. Ce motif [H-P-(S,A)-(N,D)-x-T-P] remplace le motif [H-N-L-R] conservé dans les plantes sans bétalaïne et le motif [H-N-L-x] présent dans tous les homologues bactériens et archaebactériens. Une modélisation tridimensionnelle préliminaire du site actif de Pg DODA et de son homologue dans la mousse Physcomitrella patens a montré l'importance de ce motif spécifique aux bétalaïnes pour l'accessibilité du substrat au site actif. L'analyse phylogénétique de DODA a confirmé l'évolution séparée de cette protéine chez les plantes à bétalaïnes par comparaison avec celle des plantes sans bétalaïne. Nous avons donc conclu que les bétalaïnes sont apparues par modification de l'affinité pour un substrat d'enzymes similaires à DODA, chez un ancêtre unique des Caryophyllales qui a perdu toute capacité de biosynthèse des anthocyanes. Finalement, Pg DODA n'a aucune similarité avec la protéine DODA d' Amanita muscaria, bien que celle-ci complémente aussi la pigmentation des pétales blancs de Pg. La biosynthèse des bétalaïnes est un exemple remarquable de convergence évolutive biochimique indépendante entre espèces de règnes différents. ABSTRACT Betalains are violet and yellow chromo-alkaloid pigments present in plants belonging to the order Caryophyllales and also in the fungal genera Amanita and Hygrocybe. Their short biosynthetic pathway is chemically well understood since many years, but enzymes involved in the plant pathway are still uncharacterized. The DOPA-dioxygenase from Amanita muscaria was identified (Girod and Zryd, 1991a), but numerous attempts to identify a plant homologue to the corresponding gene, failed. In order to isolate betalain-specific genes in plants, subtractive cDNA libraries were built with total RNA from white and yellow and respectively, violet immature petals from Portulaca grandiflora (Pg) genotypes. Colour-specific clones were first detected by Northern blot analysis using RNA from white and coloured petals. Positive candidates were submitted to further transcription analysis in coloured, green stems and leaves in order to assess their specific expression. Two full-length mRNAs showed a correlated expression with betalain accumulation in tissues. One of them, A.16, encodes a putative acyl-Coenzyme A oxidase (ACX), but missing the FAD binding domain essential for the ACX activity. Thus, all attempts to demonstrate its function failed. The role of this protein in the betalain biosynthesis pathway, if any, is still unknown. The second betalain-specific mRNA, L.6 (isolated by Zaiko, 2000) shows a homology with a LigB domain (pfam02900) from a bacterial extradiol 4,5-dioxygenase. It was then renamed DODA (DOPA-dioxygenase). DODA was identified in silico as a highly conserved extradiol dioxygenase due to the strict conservation of its peptidic sequence with LigB catalytic residues and iron-binding cofactor residues. Southern blot analysis showed that this gene is a single copy-gene in Pg. Transient expression of DODA protein through biolistic transformation of Pg white petals produced violet or yellow spots in individual cells. HPLC analysis of these spots showed an identity with betalain pigments present naturally in yellow and violet Pg petals, thus confirming the complementation of the recessive cc allele present in Pg white petals by Pg DODA gene. DODA homologues were identified in numerous plant species including those without betalain. Alignment of these homologues allowed the identification of a betalain-specific pattern beside a highly conserved catalytic histidine. This [H-P-(S,A)-(N,D)-x-T-P] pattern replaces a [H-N-L-R] pattern strictly conserved in non-betalain plants and a [H-N-L-x] pattern present in all bacterial and archaebacterial homologues. Preliminary three-dimensional modeling of the active site of Pg DODA and its Physcomitrella patens moss homologue revealed the importance of this betalain-specific pattern for the substrate accessibility to the DODA active site. DODA phylogenetic analysis confirmed the separate evolution of this protein in betalain-producing plants. We conclude that betalain pigments appeared in a unique ancestor of the Caryophyllales order in which anthocyanin biosynthetic pathway was impaired, by a modification of enzymes of the DODA family for substrate affinity. The Pg DODA protein has no sequence similarity with Amanita muscaria DODA, despite the fact that they both complement Pg white petals for their pigmentation. Betalain biosynthesis is an interesting example of independent biochemical evolutionary convergence between species from different kingdoms.
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Theory states that genes on the sex chromosomes have stronger effects on sexual dimorphism than genes on the autosomes. Although empirical data are not necessarily consistent with this theory, this situation may prevail because the relative role of sex-linked and autosomally inherited genes on sexual dimorphism has rarely been evaluated. We estimated the quantitative genetics of three sexually dimorphic melanin-based traits in the barn owl (Tyto alba), in which females are on average darker reddish pheomelanic and display more and larger black eumelanic feather spots than males. The plumage traits with higher sex-linked inheritance showed lower heritability and genetic correlations, but contrary to prediction, these traits showed less pronounced sexual dimorphism. Strong offspring sexual dimorphism primarily resulted from daughters not expressing malelike melanin-based traits and from sons expressing femalelike traits to similar degrees as their sisters. We conclude that in the barn owl, polymorphism at autosomal genes rather than at sex-linked genes generate variation in sexual dimorphism in melanin-based traits.
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Secondary sexual characters often signal qualities such as physiological processes associated with resistance to various sources of stress. When the expression of an ornament is not sex-limited, we can identify the costs and benefits of displaying a trait that is typical of its own sex or of the other sex. Indeed, the magnitude and sign of the covariation between physiology and the extent to which an ornament is expressed could differ between males and females if, for instance, the regulation of physiological processes is sensitive to sex hormones. Using data collected over 14 years in the nocturnal barn owl Tyto alba, we investigated how nestling body mass covaries with a heritable melanin-based sex-trait, females displaying on average larger black feather spots than males. Independently of nestling sex, year and time of the day large-spotted nestlings were heavier than small-spotted nestlings. In contrast, the magnitude and sign of the covariation between nestling body mass and the size of parental spots varied along the day in a way that depended on the year and parental gender. In poor years, offspring of smaller-spotted mothers were heavier throughout the resting period; in the morning, offspring sired by larger-spotted fathers were heavier than offspring of smaller-spotted fathers, while in the evening the opposite pattern was found. Thus, maternal and paternal coloration is differentially associated with behaviour or physiology, processes that are sensitive to time of the day and environmental factors. Interestingly, the covariation between offspring body mass and paternal coloration is more sensitive to these environmental factors than the covariation with maternal coloration. This indicates that the benefit of pairing with differently spotted males may depend on environmental conditions, which could help maintain genetic variation in the face of intense directional (sexual) selection.
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Variants of the melanocortin-1 receptor (MC1R) gene result in abrupt, naturally selected colour morphs. These genetic variants may differentially affect sexual dimorphism if one morph is naturally selected in the two sexes but another morph is naturally or sexually selected only in one of the two sexes (e.g. to confer camouflage in reproductive females or confer mating advantage in males). Therefore, the balance between natural and sexual selections can differ between MC1R variants, as suggest studies showing interspecific correlations between sexual dimorphism and the rate of nonsynonymous vs. synonymous amino acid substitutions at the MC1R. Surprisingly, how MC1R is related to within-species sexual dimorphism, and thereby to sex-specific selection, has not yet been investigated. We tackled this issue in the barn owl (Tyto alba), a species showing pronounced variation in the degree of reddish pheomelanin-based coloration and in the number and size of black feather spots. We found that a valine (V)-to-isoleucine (I) substitution at position 126 explains up to 30% of the variation in the three melanin-based colour traits and in feather melanin content. Interestingly, MC1R genotypes also differed in the degree of sexual colour dimorphism, with individuals homozygous for the II MC1R variant being 2 times redder and 2.5 times less sexually dimorphic than homozygous individuals for the VV MC1R variant. These findings support that MC1R interacts with the expression of sexual dimorphism and suggest that a gene with major phenotypic effects and weakly influenced by variation in body condition can participate in sex-specific selection processes.
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Background: Malignant hypertension is defined by marked systemic arterial hypertension with retinal haemorrhages, exudation or papilloedema. Due to the rarity of this disease and due to its non-specific symptoms and lesions, the diagnosis can be challenging. Patients and Methods We investigated the types of symptoms and ocular lesions observed with ocular fundus examination, ocular fundus photography, fluorescein angiography and optical coherence tomography in a small case series of 7 patients with malignant hypertension. Results: Median systolic blood pressure (BP) was 205 mmHg ± 21. Median diastolic BP was 150 mmHg ± 16. Decrease in visual acuity (6/7 patients) and scotoma (5/7) were the main symptoms and Elschnig spot, flamed shaped haemorrhage, serous retinal detachment, cotton wool spots and optic nerve oedema were the five most frequently observed lesions. A regression of lesions was observed after therapy of systemic hypertension. Conclusion: The association of multiple lesions strongly suggests malignant hypertension. However even in cases with only one lesion malignant hypertension should be kept in mind.
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To determine the feasibility of data transfer, an interlaboratory comparison was conducted on colon carcinoma cell line (DLD-1) proteins resolved by two-dimensional polyacrylamide gel electrophoresis either on small (6 x 7 cm) or large (16x18 cm) gels. The gels were silver-stained and scanned by laser densitometry, and the image obtained was analyzed using Melanie software. The number of spots detected was 1337+/-161 vs. 2382+/-176 for small vs. large format gels, respectively. After gel calibration using landmarks determined using pl and Mr markers, large- and small-format gels were matched and 712+/-36 proteins were found on both types of gels. Having performed accurate gel matching it was possible to acquire additional information after accessing a 2-D PAGE reference database (http://www.expasy.ch/ cgibin/map2/def?DLD1_HUMAN). Thus, the difference in gel size is not an obstacle for data transfer. This will facilitate exchanges between laboratories or consultation concerning existing databases.