Publications by authors named "F Helfenstein"

Pregnancy-associated changes in melanocytic nevi (MN), apart from size increase on the trunk, remain a topic of debate. We conducted the first prospective study to investigate dermoscopic changes in MN comparing pregnant with non-pregnant women on all body parts using a market-approved convolutional neural network (CNN). We included 25 pregnant and 25 non-pregnant women from Basel, Switzerland, who underwent standard skin cancer screenings and whose MN > 2 mm were digitally recorded and analysed by a CNN.

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Several studies have reported an increasing occurrence of poly- and perfluorinated alkyl substances (PFASs) in Arctic wildlife tissues, raising concerns due to their resistance to degradation. While some research has explored PFAS's physiological effects on birds, their impact on reproductive functions, particularly sperm quality, remains underexplored. This study aims to assess (1) potential association between PFAS concentrations in blood and sperm quality in black-legged kittiwakes (), focusing on the percentage of abnormal spermatozoa, sperm velocity, percentage of sperm motility, and morphology; and (2) examine the association of plasma levels of testosterone, corticosterone, and luteinizing hormone with both PFAS concentrations and sperm quality parameters to assess possible endocrine disrupting pathways.

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Article Synopsis
  • This study compares two MRI techniques, TWIST and GRASP, for imaging aortic diseases, focusing on their effectiveness in dealing with patient movement.
  • It involved 30 patients and assessed the image quality of vascular structures, with GRASP showing better contrast and sharpness than TWIST, which is sensitive to motion artifacts.
  • Results indicated that GRASP provided clearer images and more accurate measurements of aortic diameters compared to TWIST, despite some increased streaking artifacts in GRASP images.
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Neonicotinoid insecticides are widely used in agriculture and have been linked to various detrimental physiological effects on wild birds. Despite this, the impact of acetamiprid - a less studied member of the neonicotinoid family - on the hypothalamic-pituitary-adrenal axis responsible for the hormonal regulation of the response to stress has rarely been examined in birds. In our study, we explored the effects of acetamiprid on feather levels of corticosterone, the major end product of the HPA, and blood oxidative status of House sparrows (Passer domesticus), following the ingestion of a low, field-realistic dose during two consecutive experiments in 2015 and 2016.

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