Comment on "An early Miocene extinction in pelagic sharks".

Sibert and Rubin (Reports, 4 June 2021, p. 1105) claim to have identified a previously unidentified, major extinction event of open-ocean sharks in the early Miocene. We argue that their interpretations are based on an experimental design that does not account for a considerable rise in the sedimentation rate coinciding with the proposed event, nor for intraspecific variation in denticle morphology.

[Comparative histopathologic and sonomorphological prostate studies]. / Vergleichende histopathologische und sonomorphologische Prostatauntersuchungen.

Ten cadaver prostates were divided into 50 sections and corresponding sections were compared, using ultrasound, with respect to their echogenic structure and histomorphology. The results of normal prostatic tissues, benign prostatic hyperplasia and prostatic carcinomas are described and discussed. It was shown that malignant prostatic lesions showed echo-poor sonograms in vitro. This observation is supported by our clinical experience. Possible explanations are discussed.