Síndromes muy poco frecuentes

Dismorfología, Citogenética y Clínica: Resultados de estudios sobre los datos del ECEMCSince the year 2002, this Section of the Boletín del ECEMC: Revista de Dismorfología y Epidemiología, is dedicated to dysmorphology, cytogenetics and clinical analysis of congenital anomalies, and includes a chapter on syndromes with very low frequency. The aim of this chapter is to summarize the most important characteristics, the etiology, and the mechanisms involved in the selected syndromes. The low frequency of these syndromes, together with their probable decreasing birth prevalence due to the impact of prenatal diagnosis, imply that pediatricians and other health professionals would have less opportunity to know their clinical characteristics. This circumstance together with the overlapping of the clinical features among some of the syndromes, make difficult to perform an early diagnosis, which is important for genetic counselling, and to provide the most suitable treatment to each pacient. The syndromes included are: Aarskog, Freeman-Sheldon, Cleidocranial dysplasia, Noonan, Cardio-Facio-Cutaneous and Costello. In addition, a short summary about the differential diagnosis among Noonan, Cardio-Facio-Cutaneous and Costello syndromes is also included.N

Global status and conservation potential of reef sharks

Decades of overexploitation have devastated shark populations, leaving considerable doubt as to their ecological status1,2. Yet much of what is known about sharks has been inferred from catch records in industrial fisheries, whereas far less information is available about sharks that live in coastal habitats3. Here we address this knowledge gap using data from more than 15,000 standardized baited remote underwater video stations that were deployed on 371 reefs in 58 nations to estimate the conservation status of reef sharks globally. Our results reveal the profound impact that fishing has had on reef shark populations: we observed no sharks on almost 20% of the surveyed reefs. Reef sharks were almost completely absent from reefs in several nations, and shark depletion was strongly related to socio-economic conditions such as the size and proximity of the nearest market, poor governance and the density of the human population. However, opportunities for the conservation of reef sharks remain: shark sanctuaries, closed areas, catch limits and an absence of gillnets and longlines were associated with a substantially higher relative abundance of reef sharks. These results reveal several policy pathways for the restoration and management of reef shark populations, from direct top-down management of fishing to indirect improvement of governance conditions. Reef shark populations will only have a high chance of recovery by engaging key socio-economic aspects of tropical fisheries