Genetic conflict outweighs heterogametic incompatibility in the mouse hybrid zone?

Background  

The Mus musculus musculus/M. m. domesticus contact zone in Europe is characterised by sharp frequency discontinuities for sex chromosome markers at the centre of wider clines in allozyme frequencies.     

Infection by Contracaecum rudolphii (Nematoda: Anisakidae) in the Neotropic cormorant Phalacrocorax brasilianus,and fishes from the estuary of the Valdivia river,Chile

Seasonal parameters of infection by the nematode Contracaecum rudolphii in the Neotropic cormorant Phalacrocorax brasilianus (Phalacrocoracidae) and their relation with feeding and infection in fishes from River Valdivia, Chile, were determined. The prevalences of infection in birds were similar during seasons, whereas mean intensity and percentages of adult gravid females were higher in spring and summer, respectively. For fishes no seasonal differences were found in infection. Cormorant diet varied seasonally in relation to fish prey consumed and this can be related to seasonal differences in infection parameters of birds. The high infection in birds should be considered as a potential risk for salmoniculture.     

MicroRNA expression profiling in blood from fragile X‐associated tremor/ataxia syndrome patients

Fragile X‐associated tremor/ataxia syndrome (FXTAS) is a late‐onset neurodegenerative disorder associated with FMR1 gene premutation alleles (55–200 CGG repeats). Fragile X‐associated tremor/ataxia syndrome clinical core features include action tremor, gait ataxia, cognitive deficits progressing to dementia, and frequently parkinsonism. Although the pathogenic molecular mechanism of FXTAS is not completely understood, the restriction of the phenotype to the FMR1 premutation range has given rise to a model based on a RNA toxic gain‐of‐function. Since the identification of the first microRNAs (miRNAs) and their role in normal development, several studies have associated them with neurodegenerative diseases such as Parkinson, Alzheimer and Huntington diseases, suggesting that they play a key role in brain development, as well as in its morphogenesis. Herein, we present the characterization of miRNA expression profiles in FXTAS male patients using deep sequencing‐based technologies and microarray technology. Deep sequencing analysis evidenced 83 miRNAs that were significantly deregulated whereas microarray analysis showed 31. When comparing these results, 14 miRNAs were found deregulated in FXTAS patients. MiR‐424 and miR‐574‐3p showed significant fold change adjusted P‐values in both platforms in FXTAS patients. MiR‐424 has been founded substantially and specifically enriched in human cerebral cortical white matter of Alzheimer disease patients, which, together with cerebral atrophy, is a prominent imaging finding in individuals with FXTAS. The study provides the first systematic evidence of differential miRNA expression changes in FXTAS blood samples. Although further studies are necessary to better characterize the miRNA function in FXTAS disorder, our results suggest that they might contribute to its pathogenesis.     

Proposed follow up programme after curative resection for lower third oesophageal cancer

Cyclins are indispensable elements of the cell cycle and derangement of their function can lead to cancer formation. Recent studies have also revealed more mechanisms through which cyclins can express their oncogenic potential. This review focuses on the aberrant expression of G1/S cyclins and especially cyclin D and cyclin E; the pathways through which they lead to tumour formation and their involvement in different types of cancer. These elements indicate the mechanisms that could act as targets for cancer therapy.