142 resultados para RARE CRANIOFACIAL CLEFTS


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Protecting native biodiversity against alien invasive species requires powerful methods to anticipate these invasions and to protect native species assumed to be at risk. Here, we describe how species distribution models (SDMs) can be used to identify areas predicted as suitable for rare native species and also predicted as highly susceptible to invasion by alien species, at present and under future climate and land-use scenarios. To assess the condition and dynamics of such conflicts, we developed a combined predictive modelling (CPM) approach, which predicts species distributions by combining two SDMs fitted using subsets of predictors classified as acting at either regional or local scales. We illustrate the CPM approach for an alien invader and a rare species associated to similar habitats in northwest Portugal. Combined models predict a wider variety of potential species responses, providing more informative projections of species distributions and future dynamics than traditional, non-combined models. They also provide more informative insight regarding current and future rare-invasive conflict areas. For our studied species, conflict areas of highest conservation relevance are predicted to decrease over the next decade, supporting previous reports that some invasive species may contract their geographic range and impact due to climate change. More generally, our results highlight the more informative character of the combined approach to address practical issues in conservation and management programs, especially those aimed at mitigating the impact of invasive plants, land-use and climate changes in sensitive regions

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The Rare Cancer Network (RCN), founded in 1993, performs research involving rare tumors that are not common enough to be the focus of prospective study. Over 55 studies have either been completed or are in progress.The aim of the paper is to present an overview of the 30 studies done through the RCN to date, organized by disease site. Five studies focus on breast pathology, including sarcoma, lymphoma, phyllodes tumor, adenoid cystic carcinoma, and ductal carcinoma in situ in young women. Three studies on prostate cancer address prostatic small cell carcinoma and adenocarcinoma of young and elderly patients. Six studies on head and neck cancers include orbital and intraocular lymphoma, mucosal melanoma, pediatric nasopharyngeal carcinoma, olfactory neuroblastoma, and mucosa-associated lymphoid tissue lymphoma of the salivary glands. There were 4 central nervous system studies on patients with cerebellar glioblastoma multiforme, atypical and malignant meningioma, spinal epidural lymphoma and myxopapillary ependymoma. Outside of these disease sites, there is a wide variety of other studies on tumors ranging from uterine leiomyosarcoma to giant cell tumors of the bone. The studies done by the RCN represent a wide range of rare pathologies that were previously only studied in small series or case reports. With further growth of the RCN and collaboration between members our ability to analyze rare tumors will increase and result in better understanding of their behavior and ultimately help direct research that may improve patient outcomes.

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Rare earth elements (REE) and stable isotope compositions (delta C-13 and delta O-18) of shark teeth and phosphatic coprolites were analyzed from the Lower Maastrichtian layers of the El Haria Formation and two sequences of the Paleocene-Eocene (P/E) Chouabine Formation in the Gafsa Basin (south western of Tunisia) in order to trace the sedimentological, climatic and oceanographic conditions. The REE chemistry and their distribution in the two archives are the same for each of the studied layers indicating that the coprolites and shark teeth experienced the same early diagenetic environments. However major differences occur between the Maastrichtian and the P/E reflecting changes in the depositional conditions. The Early Maastrichtian burial environment tended to be more anoxic with REE derived from reduced FeO. While in the P/E the REE patterns mimic the modern oxic-suboxic seawater, the REE source from remineralisation of organic coating could have more significance. The oxygen isotope compositions of the structural phosphates (delta O-18(PO4)) indicate a stable and warm climate during both studied time intervals. A small offset (-0.4 parts per thousand) in the delta O-18 value between the coprolites and shark teeth show minor thermal gradient between bottom and surface water. The pronounced negative shift of 34%. in delta C-13 values recorded in the upper part of the Chouabine Formation was ascribed to the Paleocene-Eocene boundary. At the same time the lack of negative change in the delta O-18 is explained by the semi-closed situation of the Gafsa Basin, which situation also played an important role in the evolution of the organic matters in the sediment resulting in the exceptional low delta C-13 values. (C) 2008 Elsevier B.V. All rights reserved.

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RESUME Objectif : Les lymphomes épiduraux primaires représentent moins de 10% des tumeurs épidurales et de 0,1 à 3,3% de tous les lymphomes. Le but de cette étude a été d'évaluer le profil clinique de cette maladie rare, son traitement, ses résultats ainsi que ses facteurs de pronostic. Matériel et méthode : Entre 1982 et 2002, 52 patients présentant un lymphome épidural primaire ont été traités dans neuf institutions membres du Rare Cancer Network. Les critères d'inclusion comprenaient : une biopsie confirmant le lymphome non-hodgkinien, un stade IE et IIE selon la classification de Ann Arbor, un traitement à visée curative de radiothérapie combinée ou non à une chimiothérapie et un suivi d'au moins six mois. Selon la Working Formulation, 12 patients (23%) présentaient un lymphome de bas grade, 28 (54%) un grade intermédiaire et 12 (23%) un haut grade. Les hommes étaient atteints 1.9 fois plus fréquemment que les femmes. L'âge moyen était de 61 ans (intervalle : 21 à 96). Le bilan incluait un Ct-scan spinal (98%), une IRM (52%), un CT-scan thoraco-abdominal (77%) et une aspiration ou biopsie de moelle osseuse (96%). Les symptômes les plus fréquents comprenaient des douleurs dorsales (79% des patients), une faiblesse musculaire (92%) et des déficits sensoriels (71 %). Quarante-huit patients ont subi une laminectomie de décompression avec résection partielle ou complète (42% et 13% des cas respectivement), tous ont reçu une radiothérapie seule (20 patients) ou en combinaison avec une chimiothérapie (32 patients). La dose médiane totale était de 36 Gy (intervalle 6-50 Gy) avec une moyenne de 20 Gy par fraction (intervalle : 1-25). Le suivi moyen était de 71 mois (intervalle : 22-165 mois). Résultats : Suite au traitement, une progression locale a été observée chez 6 patients après un temps de latence moyen de 6 mois. Le taux de rechute systémique a été de 42% (22 patients) le plus souvent dans les ganglions lymphatiques (n=9) après un intervalle de temps moyen de 20 mois. Lors du dernier contrôle, 28 patients étaient vivants et 24 patients étaient décédés. Le taux de survie à 5 ans, le taux de survie sans maladie et le contrôle local étaient de 69%, 57% et 88% respectivement. En analyse univariée, les facteurs pronostics favorables statistiquement significatifs concernant la survie sans maladie étaient un âge inférieur à 63 ans, ainsi qu'une réponse neurologique complète. Pour la survie à 5 ans, les facteurs favorables étaient un âge inférieur à 63 ans. En analyse multivariée, les facteurs pronostics favorables pour la survie globale à 5 ans étaient une réponse neurologique complète, un traitement combiné, un volume de radiothérapie plus que focal, une dose totale de radiothérapie supérieure à 36 Gy et une résection partielle ou complète de la tumeur. En ce qui concerne la survie sans maladie, les facteurs pronostics favorables étáient un âge inférieur à 63 ans et un traitement combiné. Conclusion : Ce qui ressort de cette analyse est que le bilan diagnostic devrait inclure une IRM ou un CT-scan, un échantillon de tissu pour poser le diagnostic pathologique définitif de la lésion, une histoire médicale et un examen physique complet, une chimie sanguine, un CTscan thoraco-abdominal et une biopsie de la moelle osseuse, un PET-scan devrait également faire partie du bilan. Le traitement devrait consister, dans la phase aiguë, en une chirurgie de décompression avec ou sans résection, suivie d'une radiothérapie d'au moins 36Gy en 2 Gy par fraction et d'une chimiothérapie. Tous les patients présentant un lymphome de haut grade ou de grade intermédiaire devraient pouvoir bénéficier d'un traitement combiné.

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BACKGROUND: This study reviews the 15 year program of our Department of Pediatric Surgery for the treatment and follow-up of children born with a cleft in Benin and Togo. METHODS: We analyzed files of children born in Africa with a cleft. They were referred to us through a nongovernmental organization (NGO) between 1993 and 2008 and assessed in Africa by local pediatricians before and after surgery. Operations were performed by our team. RESULTS: Two hundred files were reviewed: 60 cases of unilateral cleft lip, seven of bilateral cleft lip, 44 of unilateral cleft lip palate (UCLP), 29 of bilateral cleft lip palate (BCLP), 53 of cleft palate (CP), three of bilateral oro-ocular cleft, one of unilateral and two of median clefts (Binder), and one of commissural cleft. Sixty-nine (35 %) of these cases were not operated in Africa: 25 (12.5 %) had not shown up, 28 (15 %) were considered unfit for surgery (Down's syndrome, HIV-positive, malnutrition, cardiac malformation), and 16 (7.5 %) were transferred to Switzerland. Palatal fistula occurred in 20 % of UCLP, 30 % of BCLP, and 16 % of CP. Evaluation of speech after palate surgery gave less than 50 % of socially acceptable speech. CONCLUSIONS: Our partnership with a NGO and a local team makes it possible to treat and subsequently follow children born with a cleft in West Africa. Surgery is performed under good conditions. If aesthetic results are a success, functional results after palate surgery need further improvement to promote integration in school and social life.

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Contexte Le plasmocytome isolé osseux est une tumeur maligne rare des cellules plasmocytaires. Les données issues de la littérature ne permettent pas de se déterminer sur la dose radiothérapeutique optimale. Dans cette perspective nous avons conduit une vaste étude rétrospective dans le but d'évaluer l'évolution, les facteurs pronostiques aunsi que la dose radiothérapeutique optimale chez les patients présentant un plasmocytome isolé. Méthodes Nous avons réunis les données de 206 patients présentant un plasmocytome isolé osseux sans évidence de myélome multiple. Chaque cas a été documenté histopathologiquement. La majorité des patients (n=169) ont été traités par radiothérapie seule, 32 par une combinaison radiothérapie-chimiothérapie, et 5 par chirurgie. La durée de suivi médiane fut de 54 mois (7-245) Résultats A 5 ans, la survie globale est de 70%, la survie sans maladie de 46% et le contrôle local de 88%. La durée médiane de développement vers une myélome multiple est de 21 mois (2-135) avec une probabilité à 5 ans de 51 %. Les analyses multivariées indiquent l'âge (<60 ans) et la taille de la tumeur (<5cm) comme facteur favorables pour survie. L'âge (<60ans) se dégage comme facteur favorable pour la survie sans maladie. La localisation de la tumeur (vertébrale vs autre) indique la probabilité de contrôle local. L'âge plus avancé (>60 ans) est le seul prédicteur de myélome multiple. Aucune relation dose-réponse n'est mise en évidence pour les doses supérieures à 30 Gy, même pour lés tumeurs les plus étendues. Conclusions Les patients les plus jeunes, principalement ceux présentant une localisation vertébrale, présentent la meilleure évolution sous traitement radiothérapeutique modéré. La progression vers le myélome multiple reste le problème thérapeutique principal. Les futures investigations devraient se focaliser sur les chimiothérapies adjuvantes ainsi que sur les nouveaux agents thérapeutiques.

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Introduction: Development of a squamous cell carcinoma (Marjolin's ulcer) is a rare but well-known complication of chronic discharging osteomyelitis. A high index of suspicion and highquality of histopathological examination are paramount in order to make the correct diagnosis. Methods: During a 15-year period (1993 and 2008), patients with long-standing chronic osteomyelitis with clinical symptoms of >1 year of duration, were retrospectively reviewed. Included were patients with histologically confirmed squamous-cell carcinoma associated with chronic wound overlying the site of chronic osteomyelitis. Clinical features and treatment approaches of these patients were analyzed. Results: During the study period, 6 patients were identified (2 women and 4 men) aged 52 to 67 years (mean 59 years). All patients had a long history of chronic discharging osteomyelitis (12, 19, 21, 30, 39 and 40 years), localized in the lower (5 patients) or upper extremitiy (1 patient). All tumors were histologically highly-differentiated squamous-cell carcinomas involving the deep soft tissues and the bone. 5 of 6 patients were initially misdiagnosed as chronic bone infection since bacteria were isolated in wound swabs, including Staphylococcus aureus (n = 3), Escherichia coli (n = 1) and Staphylococcus epidermidis (n = 1). Treatment consisted of major amputation in 4 patients and radical surgical excision in 2 patients refusing amputation. 4 patients were lost to follow-up due to return to their country of origin, the remaining 2 patients were without signs of tumor recurrence (both after major amputation). Conclusion: Malignant transformation of is a rare, but serious complication of long-standing discharging chronic osteomyelitis. All 6 patients were diagnosed after >10 years of persistent or recurrent wounds. It should be particularly suspected in case of a pathological fracture, development of exophytic mass and changes in local pattern of the ulcers itself. Multiple biopsies, including deep soft tissues and bone, are recommended to distinguish between chronic osteomyelitis, pseudoepitheliomatous hyperplasia and highly-differentiated squamous cell carcinoma. Early diagnosis and a team approach (orthopaedic and plastic surgeon) are crucial for optimal management of the patient

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The aim of the present study was to evaluate the prenatal detection of rare chromosomal autosomal abnormalities by ultrasound (US) examination. Data were obtained from 19 congenital malformation registries from 11 European countries, between 01/07/96 and 31/12/98. A total of 664,340 births were covered and 7,758 cases with congenital malformations were recorded. Rare autosomal abnormalities were diagnosed in 114 cases (6.6%) from a total of 1,738 chromosome abnormalities. There were a wide variety of autosomal abnormalities: the most common were deletions (33 cases), duplications (32 cases), trisomies of chromosomes 8, 9, 10, 14, 15, and 16 (23 cases), and unbalanced rearrangements (19 cases). Out of these cases, 45.6% were detected prenatally by US examination due to the presence of congenital anomaly. As for the types of chromosomal anomaly, unbalanced rearrangements and deletions were the most frequently detected by US. A high percentage of cases with balanced rearrangements were associated with severe congenital anomalies. The most frequent congenital anomalies detected by US were cystic hygroma (20.6%), central nervous system defects (17.6%), cardiac defects (13.2%), and diaphragm defects (10.3%). This large series offers useful information about prenatal diagnosis by US of congenital defects associated with rare autosomal abnormalities and it provides a valuable knowledge about outcome. Fetal anomalies detected by US that were associated with rare autosomal abnormalities were significantly more frequent than those associated with common chromosomal abnormalities (45.6 vs. 34.7%). This study indicates the need to increase the detection of congenital anomalies by US.

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ABSTRACTThe Online Mendelian Inheritance in Man database (OMIM) reports about 3000 Mendelian diseases of known causal gene and about 2000 that remain to be mapped. These cases are often difficult to solve because of the rareness of the disease, the structure of the family (too big or too small) or the heterogeneity of the phenotype. The goal of this thesis is to explore the current genetic tools, before the advent of ultra high throughput sequencing, and integrate them in the attempt to map the genes behind the four studied cases. In this framework we have studied a small family with a recessive disease, a modifier gene for the penetrance of a dominant mutation, a large extended family with a cardiac phenotype and clinical and/or allelic heterogeneity and we have molecularly analyzed a balanced chromosomal translocation.RESUMELa base de données des maladies à transmission mendélienne, Online Mendelian Inheritance in Man (OMIM), contient environ 3000 affections à caractère mendélien pour lesquelles le gène responsable est connu et environ 2000 qui restent à élucider.Les cas restant à résoudre sont souvent difficiles soit par le caractère intrinsèquement rare de ces maladies soit à cause de difficultés structurelles (famille trop petite ou trop étendue) ou hétérogénéité du phénotype ou génétique. Cette thèse s'inscrit avant l'arrivée des nouveaux outils de séquençage à haut débit. Son but est d'explorer les outils génétiques actuels, et de les intégrer pour trouver les gènes impliqués dans quatre cas représentant chacun une situation génétique différente : nous avons étudié une famille de quatre individus avec une transmission récessive, recherché un gène modificateur de la pénétrance de mutations dominantes, étudié une famille étendue présentant un phénotype cardiaque cliniquement et/ou allèliquement hétérogène et nous avons fait l'analyse moléculaire d'une translocation chromosomique balancée.

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Rare species have restricted geographic ranges, habitat specialization, and/or small population sizes. Datasets on rare species distribution usually have few observations, limited spatial accuracy and lack of valid absences; conversely they provide comprehensive views of species distributions allowing to realistically capture most of their realized environmental niche. Rare species are the most in need of predictive distribution modelling but also the most difficult to model. We refer to this contrast as the "rare species modelling paradox" and propose as a solution developing modelling approaches that deal with a sufficiently large set of predictors, ensuring that statistical models aren't overfitted. Our novel approach fulfils this condition by fitting a large number of bivariate models and averaging them with a weighted ensemble approach. We further propose that this ensemble forecasting is conducted within a hierarchic multi-scale framework. We present two ensemble models for a test species, one at regional and one at local scale, each based on the combination of 630 models. In both cases, we obtained excellent spatial projections, unusual when modelling rare species. Model results highlight, from a statistically sound approach, the effects of multiple drivers in a same modelling framework and at two distinct scales. From this added information, regional models can support accurate forecasts of range dynamics under climate change scenarios, whereas local models allow the assessment of isolated or synergistic impacts of changes in multiple predictors. This novel framework provides a baseline for adaptive conservation, management and monitoring of rare species at distinct spatial and temporal scales.