Temperature and solvent dependence of the dynamical landscape of tau protein conformations.

We report the variation with temperature of the ensemble distribution of conformations spanned by the tau protein in its dynamical states measured by small-angle X-ray scattering (SAXS) using synchrotron radiation. The SAXS data show a clear temperature variation of the distribution of occupied protein conformations from 293 to 318 K. More conformations with a smaller radius of gyration are occupied at higher temperature.

Two clinical cases of prosthetical rehabilitation after a tumor of the upper maxilla.

The most frequent type of treatment for patients diagnosed with a malignant neoplasia of the oral cavity is surgical removal of the tumor. As a result of the resection performed, it is difficult to obtain satisfactory results in the oral rehabilitation of these patients. When possible, fixed prostheses are the best option, because they guarantee stability, but they should be made so that the operator can remove them periodically to check the health of the oral tissues underneath and to intercept any relapse of the tumor.

Environmental methicillin-resistant Staphylococcus aureus contamination in pig herds in relation to the productive phase and application of cleaning and disinfection.

The aim of the study is to better understand MRSA environmental contamination in pig holdings in relation to the productive phase and the application of environmental cleaning and disinfection practices (C&D). This study was carried out on six herds. Dust samples from farrowing crates, weaning boxes, growing and finishing pens were collected from each herd environment prior to and after C&D and cultured for MRSA.

[Beta-hexachlorocyclohexane contamination in dairy farms of the Sacco River Valley, Latium, Italy, 2005. A retrospective cohort study].

Objective: in March 2005, the Italian National Monitoring System on Chemical Residuals in Food of Animal Origin detected levels of the pesticide beta-hexachlorocyclohexane (ß-HCH) that were 20 times higher than the legal limit of 0.003 mg/kg in bulk milk from a dairy farm in the Sacco River valley. ß-HCH, a lindane isomer and possible human carcinogen, was subsequently found in milk from several neighboring farms.

Gastric foreign body as a risk factor for gastric dilatation and volvulus in dogs.

Objective: To evaluate whether the presence of a gastric foreign body (gFB) is a significant risk factor for gastric dilatation and volvulus (GDV) in dogs and to quantify the change in likelihood of developing GDV associated with the presence of a gFB.

Design: Retrospective case-control study.

Animals: 118 large- or giant-breed dogs treated surgically for an episode of GDV and 342 large- or giant-breed dogs (> 12 months old) that underwent abdominal surgery for reasons other than GDV.

A suite of models to support the quantitative assessment of spread in pest risk analysis.

Pest Risk Analyses (PRAs) are conducted worldwide to decide whether and how exotic plant pests should be regulated to prevent invasion. There is an increasing demand for science-based risk mapping in PRA. Spread plays a key role in determining the potential distribution of pests, but there is no suitable spread modelling tool available for pest risk analysts.

Sample preparation induced artifacts in cryo-electron tomographs.

We investigated the effects of sample preparation and of the exposure to an electron beam on particles in cryo-electron tomographs. Various virus particles with icosahedral symmetry were examined, allowing a comparison of symmetrically related components that should be identical in structure but might be affected differently by these imaging artifacts. Comparison of tomographic reconstructions with previously determined structures established by an independent method showed that neither freezing nor electron beam exposure produced a significant amount of shrinkage along the z axis (thickness).

Single-step nasal reconstruction with osteocutaneous forearm flap after total rhinectomy.

Purpose: Nasal defects resulting from tumor excision can be classified according to tissues involved, such as skin, cartilage, and bone. Although in the case of "simple" defects, reconstruction with loco-regional flap eventually associated with cartilage grafts can lead to satisfactory results; in the case of total or partial rhinectomy, a minimum of 3 and a maximum of 7 operations have to be performed in the current series to achieve an acceptable end result. We present the case of a total rhinectomy reconstruction in a single-step procedure with an osteocutaneous forearm free flap (RFOFF).

Geometrid outbreak waves travel across Europe.

We show that the population ecology of the 9- to 10-year cyclic, broadleaf-defoliating winter moth (Operophtera brumata) and other early-season geometrids cannot be fully understood on a local scale unless population behaviour is known on a European scale. Qualitative and quantitative data on O. brumata outbreaks were obtained from published sources and previously unpublished material provided by authors of this article.

Continuous thermal collapse of the intrinsically disordered protein tau is driven by its entropic flexible domain.

The tau protein belongs to the category of Intrinsically Disordered Proteins (IDP), which in their native state lack a folded structure and fluctuate between many conformations. In its physiological state, tau helps nucleating and stabilizing the microtubules' (MTs) surfaces in the axons of the neurons. Tau is mainly composed by two domains: (i) the binding domain that tightly bounds the MT surfaces and (ii) the projection domain that exerts a long-range entropic repulsive force and thus provides the proper spacing between adjacent MTs.

Structure and assembly of a paramyxovirus matrix protein.

Many pleomorphic, lipid-enveloped viruses encode matrix proteins that direct their assembly and budding, but the mechanism of this process is unclear. We have combined X-ray crystallography and cryoelectron tomography to show that the matrix protein of Newcastle disease virus, a paramyxovirus and relative of measles virus, forms dimers that assemble into pseudotetrameric arrays that generate the membrane curvature necessary for virus budding. We show that the glycoproteins are anchored in the gaps between the matrix proteins and that the helical nucleocapsids are associated in register with the matrix arrays.

Cryo-electron tomography of rubella virus.

Rubella virus is the only member of the Rubivirus genus within the Togaviridae family and is the causative agent of the childhood disease known as rubella or German measles. Here, we report the use of cryo-electron tomography to examine the three-dimensional structure of rubella virions and compare their structure to that of Ross River virus, a togavirus belonging the genus Alphavirus. The ectodomains of the rubella virus glycoproteins, E1 and E2, are shown to be organized into extended rows of density, separated by 9 nm on the viral surface.

Nutritional and pathogenic fungi associated with the pine engraver beetle trigger comparable defenses in Scots pine.

Conifer bark beetles are often associated with fungal complexes whose components have different ecological roles. Some associated species are nutritionally obligate fungi, serving as nourishment to the larvae, whereas others are pathogenic blue-stain fungi known to be involved in the interaction with host defenses. In this study we characterized the local and systemic defense responses of Scots pine (Pinus sylvestris L.

Setae from the pine processionary moth (Thaumetopoea pityocampa) contain several relevant allergens.

Background: Pine processionary larvae produce urticating hairs (setae) that serve for protection against predators. Setae induce cutaneous reactions in animals and humans. The presence of toxic or allergic mechanisms is a matter of debate.

Factors associated with methicillin-resistant versus methicillin-susceptible Staphylococcus pseudintermedius infection in dogs.

Objective: To compare methicillin-resistant Staphylococcus pseudintermedius (MRSP) and methicillin-susceptible S pseudintermedius (MSSP) infections in dogs.

Design: Multicenter case-control study.

Animals: Dogs with MRSP infections were matched, by hospital, with 2 MSSP controls, with the infections occurring immediately before and after the case infection.

Intracellular pH measurements made simple by fluorescent protein probes and the phasor approach to fluorescence lifetime imaging.

A versatile pH-dependent fluorescent protein was applied to intracellular pH measurements by means of the phasor approach to fluorescence lifetime imaging. By this fit-less method we obtain intracellular pH maps under resting or altered physiological conditions by single-photon confocal or two-photon microscopy.

Staphylococcus aureus CC398: host adaptation and emergence of methicillin resistance in livestock.

Unlabelled: Since its discovery in the early 2000s, methicillin-resistant Staphylococcus aureus (MRSA) clonal complex 398 (CC398) has become a rapidly emerging cause of human infections, most often associated with livestock exposure. We applied whole-genome sequence typing to characterize a diverse collection of CC398 isolates (n = 89), including MRSA and methicillin-susceptible S. aureus (MSSA) from animals and humans spanning 19 countries and four continents.

Characterization of Salmonella occurring at high prevalence in a population of the land iguana Conolophus subcristatus in Galápagos Islands, Ecuador.

The aim of the study was to elucidate the association between the zoonotic pathogen Salmonella and a population of land iguana, Colonophus subcristatus, endemic to Galápagos Islands in Ecuador. We assessed the presence of Salmonella subspecies and serovars and estimated the prevalence of the pathogen in that population. Additionally, we investigated the genetic relatedness among isolates and serovars utilising pulsed field gel electrophoresis (PFGE) on XbaI-digested DNA and determined the antimicrobial susceptibility to a panel of antimicrobials.

Defining the thrombotic risk in patients with myeloproliferative neoplasms.

Polycythemia vera (PV) and essential thrombocythemia (ET) are two Philadelphia-negative myeloproliferative neoplasms (MPN) associated with an acquired mutation in the JAK2 tyrosine kinase gene. There is a rare incidence of progression to myelofibrosis and myeloid metaplasia in both disorders, which may or may not precede transformation to acute myeloid leukemia, but thrombosis is the main cause of morbidity and mortality. The pathophysiology of thrombosis in patients with MPN is complex.

Maturation of flaviviruses starts from one or more icosahedrally independent nucleation centres.

Flaviviruses assemble as fusion-incompetent immature particles and subsequently undergo conformational change leading to release of infectious virions. Flavivirus infections also produce combined 'mosaic' particles. Here, using cryo-electron tomography, we report that mosaic particles of dengue virus type 2 had glycoproteins organized into two regions of mature and immature structure.

Future prospects.

Cryo-electron microscopy (cryo-EM) in combination with single-particle analysis has begun to complement crystallography in the study of large macromolecules at near-atomic resolution. Furthermore, advances in cryo-electron tomography have made possible the study of macromolecules within their cellular environment. Single-particle and tomographic studies will become even more useful when technologies for improving the signal-to-noise ratio such as direct electron detectors and phase plates become widely available.

Molecular characterization of spa type t127, sequence type 1 methicillin-resistant Staphylococcus aureus from pigs.

Objectives: The aim of this study was to provide molecular characterization of methicillin-resistant Staphylococcus aureus (MRSA) spa type t127, sequence type (ST) 1 isolates, detected in a European baseline survey in holdings of breeding pigs, to determine phenotypic and genotypic drug resistance and to compare the results with those obtained from a collection of t127, ST1 MRSA and methicillin-susceptible S. aureus (MSSA) clinical isolates.

Methods: Twenty-four t127, ST1 MRSA from dust sampled in different breeding holdings in Italy, Spain and Cyprus were studied, along with 2 t127, ST1 MRSA from fattening pigs and 11 human t127, ST1 MRSA and MSSA.

International collaborative study on the occurrence of plasmid-mediated quinolone resistance in Salmonella enterica and Escherichia coli isolated from animals, humans, food and the environment in 13 European countries.

Objectives: This study was initiated to collect retrospective information on the occurrence of plasmid-mediated quinolone resistance (PMQR) in Salmonella enterica and Escherichia coli isolates in Europe and to identify the responsible genes.

Methods: Databases of national reference laboratories containing MIC values for Salmonella and E. coli isolated between 1994 and 2009 in animals, humans, food and the environment from 13 European countries were screened for isolates exhibiting a defined quinolone resistance phenotype, i.

Prevalence of cutaneous reactions to the pine processionary moth (Thaumetopoea pityocampa) in an adult population.

Background: Thaumetopoea pityocampa [pine processionary moth (PPM)] is one of the most important lepidopteran agents causing urticant cutaneous reactions in humans in Mediterranean countries. This species is also expanding northwards, because of global warming.

Objectives: To investigate the prevalence, distribution by habitat group and possible risk factors of PPM cutaneous reactions in adults.