Diversidad de musgos en comunidades vegetales asociadas a una pingüinera en la isla decepción, antártica marítima.

[spa] Con el objetivo de determinar la influencia de las pingüineras sobre la diversidad de la vegetación en la Isla Decepción, se estudió la composición de briófitas de un transecto de aproximadamente 2 km entre el Lago Irízar y la pingüinera (Pygoscelis antarcticus) de Punta La Descubierta. Fueron detectados un total de 39 carpetas de vegetación formadas principalmente por briófitos, distribuidas en tres sectores principales, aledaño al Lago Irízar, en Collado Vapor y en Punta La Descubierta. Los briófitos registrados corresponden a 15 especies de musgos y sólo 2 hepáticas, con 11 familias representadas. Se detectó que dos musgos, Sanionia uncinata y Politrychastrum alpinum, con 31 y 9 registros, dominaban las carpetas, con mayor abundancia y frecuencia. Además, se encontró un nuevo registro para la isla del musgo Bryum orbiculatifolium, el cual crece directamente asociado a la pingüinera. Además, se encontró que hay 5 especies de musgos comunes a los tres sectores, aunque otras 5 especies crecen solo en el sector de la pingüinera, diferenciándose esta comunidad de las otras dos. No se detectaron plantas vasculares en todo el sitio de estudio, por lo que se discute la posibilidad de que estos sitios se encuentran en estados de colonización temprana y donde su biota está marcada por la presencia de musgos pioneros que crecen alrededor de las pingüineras, influenciadas probablemente por el aporte de nutrientes del guano depositado.[eng] In order to determine the influence of a penguin rookery on the diversity of the vegetation on Deception Island, Maritime Antarctica, the composition of bryophytes along a transect of approximately 2 km between Lake Irízar and the penguin rookery (Pygoscelis antarcticus) of La Descubierta Point was studied. A total of 39 vegetation carpets formed mainly by bryophytes were detected, distributed between three main sectors, next to Lake Irízar, in Vapour Coil and at La Descubierta Point. The bryophytes correspond to 15 moss species and only 2 liverworts, with 11 moss families represented. Two mosses, Sanionia uncinata (31 records) and Polytrichastrum alpinum (9 records), were found to dominate the moss carpets, being also the most frequent species. In addition, a new site on the island was found with presence of the moss Bryum orbiculatifolium, which grows directly associated with the penguin rookery. Our results also show that there are 5 species of mosses common to the three sectors, another 5 species grow only in the penguin area, differentiating this community from the other two sectors. Vascular plants were not detected, indicating that the studied sites are in state of early colonization where their biota is marked by the presence of pioneer mosses associated to the penguin colony, which probably benefit from the nutrient input derived from the deposited guano

Destructive psoriatic arthritis of the temporomandibular joint: a clinical case, an overview of the pathophysiology and its differential diagnoses

Background: Clinical assessments and uniplanar images in temporomandibular disorders are not always entirely reliable. This predicament is especially important when clinicians need to determine the nature of temporomandibular joint disease, particularly when clinical features are not helpful in determining the diagnosis. Clinical presentation: A 63-year-old female patient presented with mild pain in her right TMJ. During routine imaging exams, a destructive monoarticular arthritis was noticed, producing multiple erosions of the mandibular and temporal condyles. In addition, attrition of the ceiling of the glenoid fossa was observed, generating a communication with the endocranium. Only the presumptive biological behavior revealed on TMJ imaging and the appearance of the psoriatic plaques later during follow-up helped the authors to narrow the differential diagnosis. Conclusion: The clinical case presented illustrates the difficulties in diagnosing an erosive, seronegative TMJ destruction, suggestive of a systemic arthritis