👤 Amy Koski

An abnormal accumulation of immune cells and inflammation has been described in ascending aortic aneurysm, but the factor driving disease initiation remains elusive. Interestingly, ascending aortic dilatation often occurs alongside aortic regurgitation but rarely with aortic stenosis. We sought to investigate ascending aortic aneurysm initiation by assessing the relation between aortic regurgitation and vascular activation and inflammation. In this prospective cohort study, patients with tricuspid aortic valves undergoing elective open-heart surgery were included. Aortic specimens from organ donors were obtained through the University of Miami Tissue Bank. Spatial transcriptomics measured gene expression in nondilated aortic endothelium, intima, and subintima. Immunohistochemistry determined protein expression. Aortic dimensions were recorded preoperatively and 10 years after surgery using echocardiography. Aortic gene expression affected by physiological blood flow was previously measured in Wistar rats. We show a mesenchymal activation of endothelial cells, possibly mediated by bidirectional flow, in the nondilated ascending aorta of patients with aortic regurgitation, accompanied by intimal infiltration, retention, and oxidation of apoB-containing lipoproteins. We further observed intimal upregulation of genes coding for core proteins of lipoprotein-binding proteoglycans and the Our results highlight a distinct pathological role of aortic regurgitation in ascending aortic aneurysm formation by promoting mesenchymal activation of endothelial cells and lipoprotein-related immune cell infiltration and inflammation in patients with tricuspid aortic valves. We also provide novel insights into the long-term impact of surgical aortic valve replacement on ascending aortic growth and suggest a diagnostic or therapeutic target in oxidized low-density lipoprotein cholesterol. Show less

The web-based IceBear software is a versatile tool to monitor the results of crystallization experiments and is designed to facilitate supervisor and student communications. It also records and tracks all relevant information from crystallization setup to PDB deposition in protein crystallography projects. Fully automated data collection is now possible at several synchrotrons, which means that the number of samples tested at the synchrotron is currently increasing rapidly. Therefore, the protein crystallography research communities at the University of Oulu, Weizmann Institute of Science and Diamond Light Source have joined forces to automate the uploading of sample metadata to the synchrotron. In IceBear, each crystal selected for data collection is given a unique sample name and a crystal page is generated. Subsequently, the metadata required for data collection are uploaded directly to the ISPyB synchrotron database by a shipment module, and for each sample a link to the relevant ISPyB page is stored. IceBear allows notes to be made for each sample during cryocooling treatment and during data collection, as well as in later steps of the structure determination. Protocols are also available to aid the recycling of pins, pucks and dewars when the dewar returns from the synchrotron. The IceBear database is organized around projects, and project members can easily access the crystallization and diffraction metadata for each sample, as well as any additional information that has been provided via the notes. The crystal page for each sample connects the crystallization, diffraction and structural information by providing links to the IceBear drop-viewer page and to the ISPyB data-collection page, as well as to the structure deposited in the Protein Data Bank. Show less

Genome editing has potential for the targeted correction of germline mutations. Here we describe the correction of the heterozygous MYBPC3 mutation in human preimplantation embryos with precise CRISPR-Cas9-based targeting accuracy and high homology-directed repair efficiency by activating an endogenous, germline-specific DNA repair response. Induced double-strand breaks (DSBs) at the mutant paternal allele were predominantly repaired using the homologous wild-type maternal gene instead of a synthetic DNA template. By modulating the cell cycle stage at which the DSB was induced, we were able to avoid mosaicism in cleaving embryos and achieve a high yield of homozygous embryos carrying the wild-type MYBPC3 gene without evidence of off-target mutations. The efficiency, accuracy and safety of the approach presented suggest that it has potential to be used for the correction of heritable mutations in human embryos by complementing preimplantation genetic diagnosis. However, much remains to be considered before clinical applications, including the reproducibility of the technique with other heterozygous mutations. Show less