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A dominant mutation in Snap25 causes impaired vesicle trafficking, sensorimotor gating, and ataxia in the blind-drunk mouse

The neuronal soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) complex is essential for synaptic vesicle exocytosis, but its study has been limited by the neonatal lethality of murine SNARE knockouts. Here, we describe a viable mouse line carrying a mutation in the b-isoform of neuronal SNARE synaptosomal-associated protein of 25 kDa (SNAP-25) The causative I67T missens

Immobilized metal affinity chromatography in open-loop simulated moving bed technology: purification of a heat stable histidine tagged beta-glucosidase.

Open-loop simulated moving bed (SMB) has been used for immobilized metal affinity chromatographic (IMAC) purification of his-tagged beta-glucosidase expressed in E. coli. A simplified approach based on an optimized single column protocol is used to design the open-loop SMB. A set of columns in the SMB represent one step in the chromatographic cycle i.e. there will be one set each of columns for lo

The Internet, public spheres, and political communication: Dispersion and deliberation

The theme of the Internet and the public sphere now has a permanent place on research agendas and in intellectual inquiry; it is entering the mainstream of Political communication studies. The first part of this presentation briefly pulls together key elements in the public sphere perspective, underscoring three main analytic dimensions: the structural, the representational, and the interactional.

Human C4b-binding protein, structural basis for interaction with streptococcal M protein, a major bacterial virulence factor

Human C4b-binding protein (C4BP) protects host tissue, and those pathogens able to hijack this plasma glycoprotein, from complement-mediated destruction. We now show that the first two complement control protein (CCP) modules of the C4BP alpha-chain, plus the four residues connecting them, are necessary and sufficient for binding a bacterial virulence factor, the Streptococcus pyogenes M4 (Arp4) p

The life and work of Olof Thorin (1912-2004)

This paper reviews Olof Thorin's contributions to mathematical analysis, actuarial mathematics, and probability theory, though in reversed order. In probability theory he is known for his path-breaking work on infinite divisibility. In actuarial mathematics he contributed significantly to the ruin problem. However, his international fame very much relies on his work in mathematical analysis and hi

Early penguin fossils, plus mitochondrial genomes, calibrate avian evolution

Testing models of macroevolution, and especially the sufficiency of microevolutionary processes, requires good collaboration between molecular biologists and paleontologists. We report such a test for events around the Late Cretaceous by describing the earliest penguin fossils, analyzing complete mitochondrial genomes from an albatross, a petrel, and a loon, and describe the gradual decline of pte

Cardiac and ventilatory responses to apneic exercise

This study was to elucidate the physiological effects of dynamic apneas, as performed as a discipline in breath-hold diving for recreational or competitive purposes. Therefore, cardiovascular and respiratory effects of apneas with simultaneously initiated exercise were investigated in ten trained breath-hold divers. They performed maximum duration apneas with face immersion (26 degrees C) under re

Correlated morphological and colour differences among females of the damselfly Ischnura elegans

1. The female-limited colour polymorphic damselfly Ischnura elegans has proven to be an interesting study organism both as an example of female sexual polymorphism, and in the context of the evolution of colour polymorphism, as a model of speciation processes. 2. Previous research suggests the existence of correlations between colour morph and other phenotypic traits, and the different female morp

Composite stable isotope records from a Late Weichselian lacustrine sequence at Graenge, Lolland, Denmark: Evidence of Allerod and Younger Dryas environments

Stable oxygen and carbon isotope data from a lacustrine sequence at Graenge, southeast Denmark, revealed distinct environmental changes related to Late Weichselian climatic development in the region. Comparison of isotopic records obtained from sedimentary carbonates and freshwater molluscs enabled reconstruction of changes in the lacustrine environment. The degree of thermal and chemical stratifi

A potential double role of anti-Lewis X antibodies in Helicobacter pylori-associated gastroduodenal diseases

In this study, we found Lewis X (Le(X)) determinants on 68% of Helicobacter pylori isolates from patients with chronic gastroduodenal diseases. Anti-Le(X) IgG were detected more frequently in the sera from dyspeptic children and adults (45 and 46%), with or without proved (culture) H. pylori infection, than in the sera from healthy individuals (14%, and 25%). In contrast, the prevalence of anti-Le

High frequency of microsatellite instability and loss of mismatch-repair protein expression in patients with double primary tumors of the endometrium and colorectum

BACKGROUND. Patients with the familial syndrome hereditary nonpolyposis colorectal carcinoma (HNPCC) exhibit air increased risk for several tumor types, of which the greatest lifetime risk is for colorectal and endometrial carcinoma. HNPCC is caused by a germline mutation in one of several identified mismatch repair (MMR) genes and typically presents with microsatellite instability (MSI) and frequ

Tests for causality between integrated variables using asymptotic and bootstrap distributions: theory and application

Causality tests in the Granger's sense are increasingly applied in empirical research. Since the unit root revolution in time-series analysis, several modifications of tests for causality have been introduced in the literature. One of the recent developments is the Toda-Yamamoto modified Wald (MWALD) test, which is attractive due to its simple application, its absence of pre-testing distortions, a

Platelet concentrate increases bone ingrowth into porous hydroxyapatite

Platelets contain growth factors that are believed to stimulate early fracture repair. Autologous platelets can be sequestered, concentrated, and mixed with thrombin to yield a so-called autologous growth factor gel, which might enhance bone repair or bone graft incorporation. The effect of this platelet concentrate on total tissue and bone ingrowth into porous coralline hydroxyapatite was studied

Balance between surface complexation and surface phase transformation at the alumina/water interface

This paper synthesizes and expands on the results of a recent series of investigations aimed at characterizing the interactions of orthophosphate, phenylphosphonate, and clodronate ions with hydrous alumina surfaces. The paper shows that gamma-Al2O3 is a thermodynamically unstable substance in water, which undergoes a (surface) phase transformation into bayerite, beta-Al(OH)(3). Furthermore, it al

Expansion of the BioCyc collection of pathway/genome databases to 160 genomes

The BioCyc database collection is a set of 160 pathway/genome databases (PGDBs) for most eukaryotic and prokaryotic species whose genomes have been completely sequenced to date. Each PGDB in the BioCyc collection describes the genome and predicted metabolic network of a single organism, inferred from the MetaCyc database, which is a reference source on metabolic pathways from multiple organisms. I

Pre-penetration events in fungal parasitism of nematode eggs

The present investigation deals with the main factors involved in early infection of nematode eggs by fungal parasites. We studied the effect of hydrophobicity on appressorium formation by germlings of Pochonia rubescens (syn. Verticillium suchlasporium), P. chlamydosporia (syn. V. chlamydosporium) and Lecanicillium lecanii (syn. V. lecanii). Appressoria were frequently formed on hydrophobic surfa

Uncertainty in fatigue life prediction of structures subject to Gaussian loads

In this paper we shall concentrate on Gaussian (or close to Gaussian) loads acting on a structure. The goal is to compute a measure of risk for fatigue of a component during a specific time period and the so called "safety index" will be used to combine different types of uncertainties. The presented methodology can be applied in a more general situation of environmental loads which properties may