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Hintergrund: Kopf-Hals-Tumore sind bei Erstdiagnose meist weit fortgeschritten. Tabak- und Alkohol-Konsum sind die bekanntesten Risikofaktoren. Eine Infektion mit Humanen-Papillomaviren (HPV), insbesondere Typ 16, spielt eine zunehmend wichtige Rolle in der Ätiologie und der Anteil der HPV-getriebenen[zum vollständigen Text gelangen Sie über die oben angegebene URL], 102. Jahrestagung der Vereinigung Südwestdeutscher Hals-Nasen-Ohrenärzte

Extreme habitats challenge animals with highly adverse conditions, like extreme temperatures or toxic substances. In this paper, we report of a fish (Poecilia mexicana) inhabiting a limestone cave in Mexico. Several springs inside the cave are rich in toxic H2S. We demonstrate that a behavioural adaptation, aquatic surface respiration (ASR), allows for the survival of P. mexicana in this extreme, sulphidic habitat. Without the possibility to perform ASR, the survival rate of P. mexicana was low even at comparatively low H2S concentrations. Furthermore, we show that food limitation affects the survival of P. mexicana pointing to energetically costly physiological adaptations to detoxify H2S

The newly sequenced mitochondrial genomes of 107 Asian swamp buffalo (Bubalus bubalis carabensis) allowed the reconstruction of the matrilineal divergence since ~900 Kya. Phylogenetic trees and Bayesian skyline plots suggest a role of the glacial periods in the demographic history of swamp buffalo. The ancestral swamp-buffalo mitogenome is dated ~232 ± 35 Kya. Two major macro-lineages diverged during the 2nd Pleistocene Glacial Period (~200–130 Kya), but most (~99%) of the current matrilines derive from only two ancestors (SA1′2 and SB) that lived around the Last Glacial Maximum (~26–19 Kya). During the late Holocene optimum (11–6 Kya) lineages differentiated further, and at least eight matrilines (SA1, SA2, SB1a, SB1b, SB2a, SB2b, SB3 and SB4) were domesticated around 7–3 Kya. Haplotype distributions support an initial domestication process in Southeast Asia, while subsequent captures of wild females probably introduced some additional rare lineages (SA3, SC, SD and SE). Dispersal of domestic buffaloes created local population bottlenecks and founder events that further differentiated haplogroup distributions. A lack of maternal gene flow between neighboring populations apparently maintained the strong phylogeography of the swamp buffalo matrilines, which is the more remarkable because of an almost complete absence of phenotypic differentiation.

True gazelles (genus Gazella) are a prime example of a mammalian group with considerable taxonomic confusion. This includes the descriptions of several dark grey taxa of questionable validity. Here, we examined captive dark grey putative Neumann’s gazelle Gazella erlangeri. Our concerted efforts to retrieve mitochondrial sequence information from old museum specimens of two dark grey gazelles, putative G. erlangeri and putative Muscat gazelle G. muscatensis, were unsuccessful. We did, however, find the mtDNA haplotypes of extant putative G. erlangeri to be nested within the haplotype variation of the Arabian gazelle G. arabica. The observed population genetic divergence between G. arabica and putative G. erlangeri (based on 11 nuclear microsatellites) was driven by genetic impoverishment of putative G. erlangeri. These results, along with morphological signatures of domestication (e.g., reduced brain case size), suggest genetic bottle necks and domestication effects as a consequence of prolonged captive breeding. Three hypotheses are discussed: (a) G. erlangeri and G. muscatensis are valid species but are now extinct; (b) one or both taxa represent phenotypic variation within G. arabica and, therefore, are synonyms of G. arabica; and (c) captive stocks, exhibiting the effects of domestication and inbreeding, are the sources for the descriptions of G. erlangeri and G. muscatensis. As concerns the conservation of gazelles, based on current knowledge, we strongly advise against using putative G. erlangeri for any introduction initiative but recommend the continued captive management of putative G. erlangeri. Click here to access supplementary files.

Invasive Prosopis juliflora dispersal on Farasan Kebir (Miharraq area, Wadi Matr) was investigated in relation to endozoochory by Farasan Gazelle (Gazella gazella farasani). A germination experiment was conducted to test defecated seed viability of competing P. juliflora and Acacia ehrenbergiana. It revealed that 0.0013 ± 0.0009 Acacia seeds per gram of faeces germinated, while the rate of germinating Prosopis seeds was higher (0.0053 ± 0.0022 seeds per gram of faeces). Dung middens with a Prosopis seedling (or a young tree nearby) were distinctly closer to the putative centre of Prosopis introduction (Al-Qisar and Miharraq villages) than middens without Prosopis, suggesting that gazelles whose home ranges (mean size, females : 2.07 km2, males : 0.71 km2) encompass the gardens edging the aforementioned villages contribute to the dispersal of this invasive species. Altogether, our results suggest that gazelles on the Farasan Islands contribute to the invasion success of Prosopis ; it still needs to be investigated though to what extent also domestic livestock - in particular goats - contribute to Prosopis dispersal. Based on our present data it is recommended to reduce the number of Prosopis trees in the protected area around Wadi Matr by mechanical elimination., La gazelle endémique (Gazella gazella farasani) favorise la dispersion de l’invasive Prosopis juliflora sur les îles Farasan, Arabie Saoudite. La dispersion d’une plante invasive Prosopis juliflora sur Farasan Kébir (région de Miharraq, Ouadi Matr) a été étudiée en relation avec l’endozoochorie par la Gazelle de Farasan (Gazella gazella farasani). Une expérience de germination a été réalisée afin de tester la viabilité des graines de P. juliflora et d’Acacia ehrenbergiana, deux espèces concurrentes. Elle a révélé que 0,0013 ± 0,0009 graines d’Acacia par gramme de matière fécale ont germé, soit moins que pour les graines de Prosopis (0,0053 ± 0,0022 graines par gramme). Les amas de fèces avec un semis de Prosopis (ou un jeune arbre à proximité) étaient nettement plus proches du centre supposé d’introduction de Prosopis (villages de Al-Qisar et Miharraq) que les amas sans Prosopis, ce qui suggère que les gazelles, dont le domaine vital (2,07 km2 pour les femelles ; 0,71 km2 pour les mâles) englobe les jardins adjacents aux villages sus-mentionnés, contribuent à la dispersion de cette espèce envahissante. Au total, nos résultats suggèrent que les gazelles des îles Farasan contribuent au succès de l’invasion de Prosopis. Il reste toutefois encore à étudier dans quelle mesure le bétail domestique, en particulier les chèvres, contribue à la dispersion de Prosopis. Sur la base des données actuelles, il est recommandé de réduire le nombre d’arbres de Prosopis par élimination mécanique dans la zone protégée autour de Ouadi Matr., Wronski Torsten,Mosfer Abdulwahed N.,Plath Martin. Endemic Farasan Gazelle (Gazella gazella farasani) enhances the dispersal of invasive Prosopis juliflora on Farasan Islands, Saudi Arabia. In: Revue d'Écologie (La Terre et La Vie), tome 67, n°3, 2012. pp. 329-337.

Life history traits within species often vary among different habitats. We measured female fecundity in mollies (Poecilia mexicana) from a H2S-rich cave and from a neighbouring surface habitat, as well as in laboratory-reared individuals of both populations raised in either light or continuous darkness. Compared to conspecifics from surface habitats, cave-dwelling P. mexicana had reduced fecundity (adjusted for size) in the field. In the laboratory, the fecundity of surface mollies was higher in light than in darkness, whereas fecundity in the cave mollies was almost unaffected by the ambient light conditions. Our results suggest a heritable component to the reduction in fecundity in female cave mollies. Moreover, the reduced plasticity in fecundity of cave mollies in response to light conditions might be an example of genetic assimilation or channelling of a life history trait in a population invading a new environment.

The cave molly, Poecilia mexicana, from the Cueva del Azufre, a sulfur cave in Tabasco, Mexico, ranks among the best-studied cave fishes worldwide, despite being known from a single population only. Here we describe a newly discovered second population of cave-dwelling P. mexicana from a nearby, but mostly non-sulfidic cave (Luna Azufre). Despite apparent similarities between the two populations (such as reduced eye diameter and reduced pigmentation), a geometric morphometric analysis revealed pronounced morphological differentiation between the two cave forms