ALBERT

Description: The resolution of commercially available electrocorticography (ECoG) electrodes is limited due to the large electrode spacing and, therefore, allows only a limited identification of the active nerve cell area. This paper describes a novel manufacturing process for neural implants with higher spatial resolution combining micro technological processes and Polydimethylsiloxane (PDMS) as the flexible, biocompatible material. The conductive electrode structure is deposited on a water-soluble transfer substrate by Physical Vapor Deposition (PVD) processes. Subsequently, the structure is contacted. Finally, the transfer to PDMS and dissolution of the transfer substrate takes place. In this way, high-resolution conductive structures can be produced on the PDMS. Transferred gold structures exhibit higher adhesion and conductivity than transferred platinum structures. The adhesion was improved by applying a silica surface modification to the conductive layer prior to transferring. Furthermore, the conductive layer is flexible, conductive up to an elongation of 10%, and resistant to sodium chloride solution, mimicking brain fluids. Using the introduced production process, an ECoG electrode was manufactured and characterized for its functionality in an electrochemical impedance measurement. Furthermore, the electrodes are flexible enough to adapt to different shapes. The transfer process can also be carried out in a three-dimensional mold to produce electrodes tailored to the individual patient.

Description: In modern livestock farming horned cattle pose an increased risk of injury for each other as well as for the farmers. Dehorning without anesthesia is associated with stress and pain for the calves and raises concerns regarding animal welfare. Naturally occurring structural variants causing polledness are known for most beef cattle but are rare within the dairy cattle population. The most common structural variant in beef cattle consists of a 202 base pair insertion-deletion (Polled Celtic variant). For the generation of polled offspring from a horned Holstein–Friesian bull, we isolated the Polled Celtic variant from the genome of an Angus cow and integrated it into the genome of fibroblasts taken from the horned bull using the CRISPR/Cas12a system (formerly Cpf1). Modified fibroblasts served as donor cells for somatic cell nuclear transfer and reconstructed embryos were transferred into synchronized recipients. One resulting pregnancy was terminated on day 90 of gestation for the examination of the fetus. Macroscopic and histological analyses proved a polled phenotype. The remaining pregnancy was carried to term and delivered one calf with a polled phenotype which died shortly after birth. In conclusion, we successfully demonstrated the practical application of CRISPR/Cas12a in farm animal breeding and husbandry.