Structure of the even-skipped homeodomain complexed to AT-rich DNA: new perspectives on homeodomain specificity.

even-skipped is a homeobox gene important in controlling segment patterning in the embryonic fruit fly. Its homeobox encodes a DNA binding domain which binds with similar affinities to two DNA consensus sequences, one AT-rich, the other GC-rich. We describe a crystallographic analysis of the Even-skipped homeodomain complexed to an AT-rich oligonucleotide at 2.0 A resolution. The structure reveals a novel arrangement of two homeodomains bound to one 10 bp DNA sequence in a tandem fashion. This arrangement suggests a mechanism for the homeoproteins' regulatory specificity. In addition, the functionally important residue Gln50 is observed in multiple conformations making direct and water-mediated hydrogen bonds with the DNA bases.     

Shape and volume of craniofacial cavities in intentional skull deformations

Intentional cranial deformations (ICD) have been observed worldwide but are especially prevalent in preColombian cultures. The purpose of this study was to assess the consequences of ICD on three cranial cavities (intracranial cavity, orbits, and maxillary sinuses) and on cranial vault thickness, in order to screen for morphological changes due to the external constraints exerted by the deformation device. We acquired CT‐scans for 39 deformed and 19 control skulls. We studied the thickness of the skull vault using qualitative and quantitative methods. We computed the volumes of the orbits, of the maxillary sinuses, and of the intracranial cavity using haptic‐aided semi‐automatic segmentation. We finally defined 3D distances and angles within orbits and maxillary sinuses based on 27 anatomical landmarks and measured these features on the 58 skulls. Our results show specific bone thickness patterns in some types of ICD, with localized thinning in regions subjected to increased pressure and thickening in other regions. Our findings confirm that volumes of the cranial cavities are not affected by ICDs but that the shapes of the orbits and of the maxillary sinuses are modified in circumferential deformations. We conclude that ICDs can modify the shape of the cranial cavities and the thickness of their walls but conserve their volumes. These results provide new insights into the morphological effects associated with ICDs and call for similar investigations in subjects with deformational plagiocephalies and craniosynostoses. Am J Phys Anthropol 151:110–119, 2013. © 2013 Wiley Periodicals, Inc.     

Cerebral: a Cytoscape plugin for layout of and interaction with biological networks using subcellular localization annotation

Cerebral (Cell Region-Based Rendering And Layout) is an open-source Java plugin for the Cytoscape biomolecular interaction viewer. Given an interaction network and subcellular localization annotation, Cerebral automatically generates a view of the network in the style of traditional pathway diagrams, providing an intuitive interface for the exploration of a biological pathway or system. The molecules are separated into layers according to their subcellular localization. Potential products or outcomes of the pathway can be shown at the bottom of the view, clustered according to any molecular attribute data-protein function-for example. Cerebral scales well to networks containing thousands of nodes. AVAILABILITY: http://www.pathogenomics.ca/cerebral     

The Rockefeller University Hospital (1910-2010): creating the science of medicine

The year 2010 marked the centennial of the Rockefeller University Hospital, one of the great philanthropic achievements of 20th-century science. For 100 years, the Hospital played a central role in the development and growth of medical science by enabling physician-scientists to make intensive study of human biology and disease. With ingenuity and devotion, they greatly enriched clinical medicine as well as basic biological science. This account emphasizes the founding and first half-century of the Hospital as it became a germinal center for clinical investigation. The second half of the century saw rapid change in medicine and health care with vexing problems, many yet unsolved. This history should serve as a call to arms for maintaining the linkage of science and medicine, supporting patient-oriented research as a basic discipline of medicine.     

Relationships between lipid peroxidation and anoxia tolerance in a range of species during post-anoxic reaeration

Peroxidation was studied in anoxically treated plant tissues and quantified as conjugated dienes/trienes in the total lipid fraction and as the production of thiobarbituric acid reactive substances (TBARS). Oxidative stress caused by re-exposure of plants to oxygen led to an increase of conjugated diene/triene formation in rhizomes of Iris germanica and roots of wheat ( Triticum aestivum L.) and oats ( Avena sativa L.), and after a long anoxic exposure (45 days) in the rhizomes of the very anoxia tolerant Iris pseudacorus . Second derivative (SD) spectrophotometry of the UV spectrum of lipid extracts confirmed the formation of dienes. However, determination of TBARS in Iris spp. showed no lipid peroxidation in the anoxia tolerant I. pseudacorus . In the rhizomes of the anoxia intolerant I. germanica , elevated levels of TBARS correlated positively with conjugated diene/triene formation. The results suggest that anoxic stress may induce qualitative changes in membrane lipids, as indicated by lipid peroxidation after restoration of aerobic conditions. The rate of lipid peroxidation correlated negatively with anoxic stress tolerance.     

Microplastic ingestion ubiquitous in marine turtles

Despite concerns regarding the environmental impacts of microplastics, knowledge of the incidence and levels of synthetic particles in large marine vertebrates is lacking. Here, we utilize an optimized enzymatic digestion methodology, previously developed for zooplankton, to explore whether synthetic particles could be isolated from marine turtle ingesta. We report the presence of synthetic particles in every turtle subjected to investigation (n = 102) which included individuals from all seven species of marine turtle, sampled from three ocean basins (Atlantic [ATL]: n = 30, four species; Mediterranean (MED): n = 56, two species; Pacific (PAC): n = 16, five species). Most particles (n = 811) were fibres (ATL: 77.1% MED: 85.3% PAC: 64.8%) with blue and black being the dominant colours. In lesser quantities were fragments (ATL: 22.9%: MED: 14.7% PAC: 20.2%) and microbeads (4.8%; PAC only; to our knowledge the first isolation of microbeads from marine megavertebrates). Fourier transform infrared spectroscopy (FT‐IR) of a subsample of particles (n = 169) showed a range of synthetic materials such as elastomers (MED: 61.2%; PAC: 3.4%), thermoplastics (ATL: 36.8%: MED: 20.7% PAC: 27.7%) and synthetic regenerated cellulosic fibres (SRCF; ATL: 63.2%: MED: 5.8% PAC: 68.9%). Synthetic particles being isolated from species occupying different trophic levels suggest the possibility of multiple ingestion pathways. These include exposure from polluted seawater and sediments and/or additional trophic transfer from contaminated prey/forage items. We assess the likelihood that microplastic ingestion presents a significant conservation problem at current levels compared to other anthropogenic threats.