Total body water changes using segmental bioimpedance in healthy population with similar anthropometry

Electrical bioimpedance was measured in 7 body segments, and also with the standard right-side method, using 11 electrodes at 6 different frequencies in 8 healthy male subjects with similar anthropometry. Our objective was to determine the capability of segmental bioimpedance measurements to estimate small changes of water on each segment (TWsegi)and total body water (TBW) in comparison with the standard right-side method. Water was also estimated with 40K and DXA. Volunteers were measured before and after a 3.5% water load of their individual TBW. The expected TBW mean increment after water load was 1.45 l. The estimator with lower Standard Error SE was the weight of the subject (0.15 l). For impedance methods, the SE of the segmental method was 0.94 l vs. 1.41 l for right-side. Segmental volume changes obtained by DXA and Impedance compared with expected values showed maximum differences of almost 2 l for DXA and 0.5 l for Z in the abdomen. In conclusion, in a healthy sample with similar anthropometry, such as astronauts and athletes, the use of a segmental impedance method improves the accuracy of the right-side method to estimate TBW. Changes in water segments estimated by impedance where more close to expected values than using DXA.Postprint (author’s final draft

Evolution of monogenetic rhyolite volcanoes: Vinicky, Eastern Slovakia

Four essential volcanic units have been recognized in the late Middle Miocene rhyolite complex at the southern side of the Zemplín horst next to the village Viničky. A succession of ash/pumice flow, surge and fall deposits separated by horizons of eolian dust and paleosoil in total thickness >15 m forms the lower unit. It represents distal facies deposits of subplinian/plinian/phreatoplinian type eruptions at unidentified centers. The second unit rests upon the lower one with unconformity marking a period of erosion. It consists of coarse phreatic/phreatomagmatic pyroclastic rocks with fragments of basement rocks and glassy dacite/ rhyodacite. They represent proximal facies of a phreatomagmatic pyroclastic ring. Both units are truncated by a rhyolite extrusive dome, formed of perlite and perlitic breccias at its margin. Emplacement of the dome concluded activity of local centers northwest of Viničky. An extensive rhyolite coulee represents the fourth, uppermost volcanic unit. It is 40 – 70 m thick, formed of felsitic rhyolite with perlite and perlitic breccia at the base. Orientation of flow banding implies that the Borsuk extrusive dome 1 km northeast of Viničky was a source of the coulee. The dome and coulee form together one rhyolite body of the dome-flow type. With exception of the distal facies tuffs at the base the rhyolite complex represents most probably products of three overlapping monogenetic volcanoe

Crustal influx, indentation, ductile thinning and gravity redistribution in a continental wedge: Building a Moldanubian mantled gneiss dome with underthrust Saxothuringian material (European Variscan belt)

27 p.International audience[1] The contribution of lateral forces, vertical load, gravity redistribution and erosion to the origin of mantled gneiss domes in internal zones of orogens remains debated. In the Orlica-Snieznik dome (Moldanubian zone, European Variscan belt), the polyphase tectono-metamorphic history is initially characterized by the development of subhorizontal fabrics associated with medium- to high-grade metamorphic conditions in different levels of the crust. It reflects the eastward influx of a Saxothuringian-type passive margin sequence below a Teplá-Barrandian upper plate. The ongoing influx of continental crust creates a thick felsic orogenic root with HP rocks and migmatitic orthogneiss. The orogenic wedge is subsequently indented by the eastern Brunia microcontinent producing a multiscale folding of the orogenic infrastructure. The resulting kilometre-scale folding is associated with the variable burial of the middle crust in synforms and the exhumation of the lower crust in antiforms. These localized vertical exchanges of material and heat are coeval with a larger crustal-scale folding of the whole infrastructure generating a general uplift of the dome. It is exemplified by increasing metamorphic conditions and younging of 40Ar/39Ar cooling ages toward the extruded migmatitic subdomes cored by HP rocks. The vertical growth of the dome induces exhumation by pure shear-dominated ductile thinning laterally evolving to non-coaxial detachment faulting, while erosion feeds the surrounding sedimentary basins. Modeling of the Bouguer anomaly grid is compatible with crustal-scale mass transfers between a dense superstructure and a lighter infrastructure. The model implies that the Moldanubian Orlica-Snieznik mantled gneiss dome derives from polyphase recycling of Saxothuringian material

Improved assay-dependent searching of nucleic acid sequence databases

Nucleic acid-based biochemical assays are crucial to modern biology. Key applications, such as detection of bacterial, viral and fungal pathogens, require detailed knowledge of assay sensitivity and specificity to obtain reliable results. Improved methods to predict assay performance are needed for exploiting the exponentially growing amount of DNA sequence data and for reducing the experimental effort required to develop robust detection assays. Toward this goal, we present an algorithm for the calculation of sequence similarity based on DNA thermodynamics. In our approach, search queries consist of one to three oligonucleotide sequences representing either a hybridization probe, a pair of Padlock probes or a pair of PCR primers with an optional TaqMan™ probe (i.e. in silico or ‘virtual’ PCR). Matches are reported if the query and target satisfy both the thermodynamics of the assay (binding at a specified hybridization temperature and/or change in free energy) and the relevant biological constraints (assay sequences binding to the correct target duplex strands in the required orientations). The sensitivity and specificity of our method is evaluated by comparing predicted to known sequence tagged sites in the human genome. Free energy is shown to be a more sensitive and specific match criterion than hybridization temperature

FAD binding, cobinamide binding and active site communication in the corrin reductase (CobR)

Adenosylcobalamin, the coenzyme form of vitamin B12, is one Nature's most complex coenzyme whose de novo biogenesis proceeds along either an anaerobic or aerobic metabolic pathway. The aerobic synthesis involves reduction of the centrally chelated cobalt metal ion of the corrin ring from Co(II) to Co(I) before adenosylation can take place. A corrin reductase (CobR) enzyme has been identified as the likely agent to catalyse this reduction of the metal ion. Herein, we reveal how Brucella melitensis CobR binds its coenzyme FAD (flavin dinucleotide) and we also show that the enzyme can bind a corrin substrate consistent with its role in reduction of the cobalt of the corrin ring. Stopped-flow kinetics and EPR reveal a mechanistic asymmetry in CobR dimer that provides a potential link between the two electron reduction by NADH to the single electron reduction of Co(II) to Co(I)

Structural neural networks subserving oculomotor function in first-episode schizophrenia

BACKGROUND: Smooth pursuit and antisaccade abnormalities are well documented in schizophrenia, but their neuropathological correlates remain unclear. METHODS: In this study, we used statistical parametric mapping to investigate the relationship between oculomotor abnormalities and brain structure in a sample of first-episode schizophrenia patients (n = 27). In addition to conventional volumetric magnetic resonance imaging, we also used magnetization transfer ratio, a technique that allows more precise tissue characterization. RESULTS: We found that smooth pursuit abnormalities were associated with reduced magnetization transfer ratio in several regions, predominantly in the right prefrontal cortex. Antisaccade errors correlated with gray matter volume in the right medial superior frontal cortex as measured by conventional magnetic resonance imaging but not with magnetization transfer ratio. CONCLUSIONS: These preliminary results demonstrate that specific structural abnormalities are associated with abnormal eye movements in schizophrenia

MICA: desktop software for comprehensive searching of DNA databases

BACKGROUND: Molecular biologists work with DNA databases that often include entire genomes. A common requirement is to search a DNA database to find exact matches for a nondegenerate or partially degenerate query. The software programs available for such purposes are normally designed to run on remote servers, but an appealing alternative is to work with DNA databases stored on local computers. We describe a desktop software program termed MICA (K-Mer Indexing with Compact Arrays) that allows large DNA databases to be searched efficiently using very little memory. RESULTS: MICA rapidly indexes a DNA database. On a Macintosh G5 computer, the complete human genome could be indexed in about 5 minutes. The indexing algorithm recognizes all 15 characters of the DNA alphabet and fully captures the information in any DNA sequence, yet for a typical sequence of length L, the index occupies only about 2L bytes. The index can be searched to return a complete list of exact matches for a nondegenerate or partially degenerate query of any length. A typical search of a long DNA sequence involves reading only a small fraction of the index into memory. As a result, searches are fast even when the available RAM is limited. CONCLUSION: MICA is suitable as a search engine for desktop DNA analysis software