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Intelligent TEM control allows automated, unsupervised and efficient cryo-EM data collection.The system includes ANFIS-based detection of single-particles during the automated sessions.A classic FIS system makes appropriate decisions during the session, as would an expert microscopist. Cryo-electron microscopy (cryo-EM) is a three-dimensional (3D) averaging technique that makes use of two-dimensional (2D) images of biological macromolecules preserved in a thin layer of vitreous ice. Recent advances in the field have facilitated the evolution of cryo-EM towards atomic resolution, and the technique provides 3D maps with detailed description of biological macromolecules. Data acquisition at the transmission electron microscope (TEM) is the first crucial step during the single-particle analysis workflow in cryo-EM. In order to exploit the potential of this structural technique for atomic or near-atomic resolution, the initial collection must allow recording of large datasets and, hence, requires operating the TEM in automated mode. The quality of the acquired dataset relies, however, on the expertise of researchers and unsupervised operations might result in low data quality. This work presents the first expert system integrated in a novel scheme to automate cryo-EM data acquisition in a TEM. This development takes advantage of fuzzy logic systems to integrate the working mode of an expert in a linguistic manner and to learn from acquired data through an adaptive network. A new method based on different image-processing algorithms and on adaptive neuro-fuzzy inference systems (ANFIS) identifies, in an unsupervised manner, the single-particles present in cryo-EM images during the automated acquisition on a TEM. This single-particle identification system is integrated in a new intelligent control scheme to automate cryo-EM data acquisition. A classic fuzzy inference system (FIS) was programmed to make appropriate decisions during the session. The designed system can be trained for a specific sample and allows for unsupervised but efficient data collection imitating the working mode of an experienced microscopist.

Recent advances in the recovery and analysis of ancient DNA (aDNA) and application of isotopic analysis of tissue obtained from mummified human remains has been accompanied by continued advances in non-invasive imaging using X-ray computed tomography (CT) and use of minimally invasive surgical techniques employing small fibre-optic endoscopes. We used these state-of-the-art techniques to examine ancient Egyptian mummies in the Egyptian Museum and Papyrus Collection of Berlin, obtaining bone samples for aDNA, stable isotope analyses and radiocarbon dating. CT and endoscopic guidance were applied to locate and biopsy bones using pre-existing access points in order to avoid any further damage to the precious specimens. Here we provide guidelines to obtain bone samples of fully wrapped mummies in a minimally invasive way, by using a combination of computed tomography and endoscopic guided biopsy.

Paleogenetics offers a unique opportunity to study human evolution, population dynamics, and disease evolution in situ. Although histologic and computed x-ray tomographic investigations of ancient mummies have clearly shown that atherosclerosis has been present in humans for more than 5,000 years, limited data are available on the presence of genetic predisposition for cardiovascular disease in ancient human populations. In a previous whole-genome study of the Tyrolean Iceman, a 5,300-year-old glacier mummy from the Alps, an increased risk for coronary heart disease was detected. The Iceman's genome revealed several single nucleotide polymorphisms that are linked with cardiovascular disease in genome-wide association studies. Future genetic studies of ancient humans from various geographic origins and time periods have the potential to provide more insights into the presence and possible changes of genetic risk factors in our ancestors. The study of ancient humans and a better understanding of the interaction between environmental and genetic influences on the development of heart diseases may lead to a more effective prevention and treatment of the most common cause of death in the modern world.HighlightsOldest evidence on the presence of genetic predisposition for cardiovascular disease in the 5,300-year-old Tyrolean Iceman.Future genetic studies of ancient humans have the potential to provide more insights into the presence and possible changes of genetic risk factors in our ancestors.The study of ancient humans and a better understanding of the interaction between environmental and genetic influences on the development of heart diseases may lead to more effective prevention and treatment.

Objectives The purpose of this study was to determine whether ancient Egyptians had atherosclerosis. Background The worldwide burden of atherosclerotic disease continues to rise and parallels the spread of diet, lifestyles, and environmental risk factors associated with the developed world. It is tempting to conclude that atherosclerotic cardiovascular disease is exclusively a disease of modern society and did not affect our ancient ancestors. Methods We performed whole body, multislice computed tomography scanning on 52 ancient Egyptian mummies from the Middle Kingdom to the Greco-Roman period to identify cardiovascular structures and arterial calcifications. We interpreted images by consensus reading of 7 imaging physicians, and collected demographic data from historical and museum records. We estimated age at the time of death from the computed tomography skeletal evaluation. Results Forty-four of 52 mummies had identifiable cardiovascular (CV) structures, and 20 of these had either definite atherosclerosis (defined as calcification within the wall of an identifiable artery, n = 12) or probable atherosclerosis (defined as calcifications along the expected course of an artery, n = 8). Calcifications were found in the aorta as well as the coronary, carotid, iliac, femoral, and peripheral leg arteries. The 20 mummies with definite or probable atherosclerosis were older at time of death (mean age 45.1 ± 9.2 years) than the mummies with CV tissue but no atherosclerosis (mean age 34.5 ± 11.8 years, p 2,000 years. Conclusions Atherosclerosis is commonplace in mummified ancient Egyptians.

The Spalt-like family of zinc finger transcription factors is conserved throughout evolution and is involved in fundamental processes during development and during embryonic stem cell maintenance. Although human SALL1 is modified by SUMO-1 in vitro, it is not known whether this post-translational modification plays a role in regulating the activity of this family of transcription factors. Here, we show that the Drosophila Spalt transcription factors are modified by sumoylation. This modification influences their nuclear localization and capacity to induce vein formation through the regulation of target genes during wing development. Furthermore, spalt genes interact genetically with the sumoylation machinery to repress vein formation in intervein regions and to attain the wing final size. Our results suggest a new level of regulation of Sall activity in vivo during animal development through post-translational modification by sumoylation. The evolutionary conservation of this family of transcription factors suggests a functional role for sumoylation in vertebrate Sall members.

Thoracic aortic calcium (TAC) is thought to be a manifestation of atherosclerosis with risk factors similar to those for CAD. To better understand TAC, we examined the Tsimane, a remote Bolivian Amazonian population with few CV factors and the lowest recorded levels of coronary artery calcium (CAC

How can Ena/VASP proteins promote actin-based movement of the intracellular pathogen Listeria or rapid protrusion of lamellipodia but at the same time inhibit cell translocation? A report in the May 17(th) issue of Cell now offers a possible explanation for this conundrum. Bear et al. report that Ena/VASP proteins regulate cell motility by competing with capping proteins to control actin filament length and geometry at the leading edge of cells.