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Glycans Confer Specificity to the Recognition of Ganglioside Receptors by Botulinum Neurotoxin A

The highly poisonous botulinum neurotoxins, produced by the bacterium Clostridium botulinum, act on their hosts by a high-affinity association to two receptors on neuronal cell surfaces as the first step of invasion. The glycan motifs of gangliosides serve as initial coreceptors for these protein complexes, whereby a membrane protein receptor is bound. Herein we set out to characterize the carbohy

Analytical theories for near coplanar and polar circumbinary orbits

The recently discovered Kepler circumbinary systems and the circumbinary polar-ring debris disc in the 99 Herculis system call for the study of circumbinary orbits. As an approximation, it is advisable to investigate the problem with the assumption that the outer body is massless. In such a scheme, we briefly summarize the main characteristics of the evolution of the orbits and give the general so

Human NUDT22 Is a UDP-Glucose/Galactose Hydrolase Exhibiting a Unique Structural Fold

Human NUDT22 belongs to the diverse NUDIX family of proteins, but has, until now, remained uncharacterized. Here we show that human NUDT22 is a Mg2+-dependent UDP-glucose and UDP-galactose hydrolase, producing UMP and glucose 1-phosphate or galactose 1-phosphate. We present the structure of human NUDT22 alone and in a complex with the substrate UDP-glucose. These structures reveal a partially cons

Identification of a Botulinum Neurotoxin-like Toxin in a Commensal Strain of Enterococcus faecium

Botulinum neurotoxins (BoNTs), produced by various Clostridium strains, are a family of potent bacterial toxins and potential bioterrorism agents. Here we report that an Enterococcus faecium strain isolated from cow feces carries a BoNT-like toxin, designated BoNT/En. It cleaves both VAMP2 and SNAP-25, proteins that mediate synaptic vesicle exocytosis in neurons, at sites distinct from known BoNT

Protein phosphatase inhibitors potentiate Ca2+/calmodulin-dependent protein kinase II activity in rat pancreatic acinar cells.

Cholecystokinin (CCK) is known to rapidly and transiently increase both [Ca2+]iand autonomous CaM kinase II activity in rat pancreatic acini. Because induction of autonomous activity may involve intramolecular autophosphorylation, the effects of protein phosphatase inhibitors were examined. None of the inhibitors tested (okadaic acid, calyculin A, and cyclosporin A) affected basal activity. Okadai

City level carbon mitigation strategies : What are their true impacts?

This paper addresses the problems associated with ambitious greenhouse gas (GHG) emission cut-off targets set for cities in recent years. Even though many cities have adopted an active approach to sustainability issues and climate change mitigation, they often lack appropriate and effective tools for achieving the cut-off targets. The primary purpose of this paper is to demonstrate the utilisation

A rat model of otitis media with effusion caused by eustachian tube obstruction with and without Streptococcus pneumoniae infection : Methods and course

OBJECTIVE: To describe the clinical and histopathologic progression of a rat model of otitis media with effusion caused by eustachian tube obstruction (ETO) with and without Streptococcus pneumoniae infection. METHODS: In 164 rats, the left, bony eustachian tube was approached via a ventral incision and obstructed with dental material. Then 108 rats were infected via an intrabullar injection with

Myringosclerosis caused by increased oxygen concentration in traumatized tympanic membranes experimental study

The purpose of this study was to elucidate possible relationships between the oxygen concentration of the middle ear cavity and the development of myringosclerosis. Three groups of rats with myringotomized tympanic membranes were exposed to different oxygen concentrations of 10%, 15%, and 40%, respectively, for 1 week. A fourth group was kept in ambient air. Two other groups of rats with myringoto

Sloan Digital Sky Survey IV : Mapping the Milky Way, Nearby Galaxies, and the Distant Universe

We describe the Sloan Digital Sky Survey IV (SDSS-IV), a project encompassing three major spectroscopic programs. The Apache Point Observatory Galactic Evolution Experiment 2 (APOGEE-2) is observing hundreds of thousands of Milky Way stars at high resolution and high signal-to-noise ratios in the near-infrared. The Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey is obtaining spa

Properties of g→b¯b at small opening angles in pp collisions with the ATLAS detector at √s=13 TeV

The fragmentation of high-energy gluons at small opening angles is largely unconstrained by present measurements. Gluon splitting to b-quark pairs is a unique probe into the properties of gluon fragmentation because identified b-tagged jets provide a proxy for the quark daughters of the initial gluon. In this study, key differential distributions related to the g→bb process are measured using 33 f

Models of our Galaxy - II

Stars near the Sun oscillate both horizontally and vertically. In a previous paper by Binney it was assumed that the coupling between these motions can be modelled by determining the horizontal motion without reference to the vertical motion, and recovering the coupling between the motions by assuming that the vertical action is adiabatically conserved as the star oscillates horizontally. Here, we