1,189 research outputs found
Paralytic shellfish poisoning (PSP) toxin binders for optical biosensor technology: problems and possibilities for the future: a review
This review examines the developments in optical biosensor technology, which uses the phenomenon of surface plasmon resonance, for the detection of paralytic shellfish poisoning (PSP) toxins. Optical biosensor technology measures the competitive biomolecular interaction of a specific biological recognition element or binder with a target toxin immobilised onto a sensor chip surface against toxin in a sample. Different binders such as receptors and antibodies previously employed in functional and immunological assays have been assessed. Highlighted are the difficulties in detecting this range of low molecular weight toxins, with analogues differing at four chemical substitution sites, using a single binder. The complications that arise with the toxicity factors of each toxin relative to the parent compound, saxitoxin, for the measurement of total toxicity relative to the mouse bioassay are also considered. For antibodies, the cross-reactivity profile does not always correlate to toxic potency, but rather to the toxin structure to which it was produced. Restrictions and availability of the toxins makes alternative chemical strategies for the synthesis of protein conjugate derivatives for antibody production a difficult task. However, when two antibodies with different cross-reactivity profiles are employed, with a toxin chip surface generic to both antibodies, it was demonstrated that the cross-reactivity profile of each could be combined into a single-assay format. Difficulties with receptors for optical biosensor analysis of low molecular weight compounds are discussed, as are the potential of alternative non-antibody-based binders for future assay development in this area
Prediction of marbofloxacin dosage for the pig pneumonia pathogens Actinobacillus pleuropneumoniae and Pasteurella multocida by pharmacokinetic/pharmacodynamic modelling
PK/PD integration data. (DOCX 7 kb
Can We Really Prevent Suicide?
Every year, suicide is among the top 20 leading causes of death globally for all ages. Unfortunately, suicide is difficult to prevent, in large part because the prevalence of risk factors is high among the general population. In this review, clinical and psychological risk factors are examined and methods for suicide prevention are discussed. Prevention strategies found to be effective in suicide prevention
include means restriction, responsible media coverage, and general public education, as well identification methods such as screening, gatekeeper training, and primary care physician education. Although the treatment for preventing suicide is difficult, follow-up that includes pharmacotherapy, psychotherapy, or both may be useful. However, prevention methods cannot be restricted to the individual. Community, social, and policy interventions will also be essentia
H4 Histamine Receptors Mediate Cell Cycle Arrest in Growth Factor-Induced Murine and Human Hematopoietic Progenitor Cells
The most recently characterized H4 histamine receptor (H4R) is expressed preferentially in the bone marrow, raising the question of its role during hematopoiesis. Here we show that both murine and human progenitor cell populations express this receptor subtype on transcriptional and protein levels and respond to its agonists by reduced growth factor-induced cell cycle progression that leads to decreased myeloid, erythroid and lymphoid colony formation. H4R activation prevents the induction of cell cycle genes through a cAMP/PKA-dependent pathway that is not associated with apoptosis. It is mediated specifically through H4R signaling since gene silencing or treatment with selective antagonists restores normal cell cycle progression. The arrest of growth factor-induced G1/S transition protects murine and human progenitor cells from the toxicity of the cell cycle-dependent anticancer drug Ara-C in vitro and reduces aplasia in a murine model of chemotherapy. This first evidence for functional H4R expression in hematopoietic progenitors opens new therapeutic perspectives for alleviating hematotoxic side effects of antineoplastic drugs
Quantitative assessment of tarsal morphology illuminates locomotor behaviour in Paleocene mammals following the end-Cretaceous mass extinction
Reconfigurable superconducting vortex pinning potential for magnetic disks in hybrid structures
High resolution scanning Hall probe microscopy has been used to directly visualise the superconducting vortex behavior in hybrid structures consisting of a square array of micrometer-sized Py ferromagnetic disks covered by a superconducting Nb thin film. At remanence the disks exist in almost fully flux-closed magnetic vortex states, but the observed cloverleaf-like stray fields indicate the presence of weak in-plane anisotropy. Micromagnetic simulations suggest that the most likely origin is an unintentional shape anisotropy. We have studied the pinning of added free superconducting vortices as a function of the magnetisation state of the disks, and identified a range of different phenomena arising from competing energy contributions. We have also observed clear differences in the pinning landscape when the superconductor and the ferromagnet are electron ically coupled or insulated by a thin dielectric layer, with an indication of non-trivial vortex-vortex interactions. We demonstrate a complete reconfiguration of the vortex pinning potential when the magnetisation of the disks evolves from the vortex-like state to an onion-like one under an in-plane magnetic field. Our results are in good qualitative agreement with theoretical predictions and could form the basis of novel superconducting devices based on reconfigurable vortex pinning sites
Planetary population synthesis
In stellar astrophysics, the technique of population synthesis has been
successfully used for several decades. For planets, it is in contrast still a
young method which only became important in recent years because of the rapid
increase of the number of known extrasolar planets, and the associated growth
of statistical observational constraints. With planetary population synthesis,
the theory of planet formation and evolution can be put to the test against
these constraints. In this review of planetary population synthesis, we first
briefly list key observational constraints. Then, the work flow in the method
and its two main components are presented, namely global end-to-end models that
predict planetary system properties directly from protoplanetary disk
properties and probability distributions for these initial conditions. An
overview of various population synthesis models in the literature is given. The
sub-models for the physical processes considered in global models are
described: the evolution of the protoplanetary disk, the planets' accretion of
solids and gas, orbital migration, and N-body interactions among concurrently
growing protoplanets. Next, typical population synthesis results are
illustrated in the form of new syntheses obtained with the latest generation of
the Bern model. Planetary formation tracks, the distribution of planets in the
mass-distance and radius-distance plane, the planetary mass function, and the
distributions of planetary radii, semimajor axes, and luminosities are shown,
linked to underlying physical processes, and compared with their observational
counterparts. We finish by highlighting the most important predictions made by
population synthesis models and discuss the lessons learned from these
predictions - both those later observationally confirmed and those rejected.Comment: 47 pages, 12 figures. Invited review accepted for publication in the
'Handbook of Exoplanets', planet formation section, section editor: Ralph
Pudritz, Springer reference works, Juan Antonio Belmonte and Hans Deeg, Ed
The osteology of ‘Periptychus carinidens’: a robust, ungulate-like placental mammal (Mammalia: Periptychidae) from the Paleocene of North America
Periptychus is the archetypal genus of Periptychidae, a clade of prolific Paleocene 'condylarth' mammals from North America that were among the first placental mammals to radiate after the end-Cretaceous extinction, remarkable for their distinctive dental anatomy. A comprehensive understanding of the anatomy of Periptychus has been hindered by a lack of cranial and postcranial material and only cursory description of existing material. We comprehensively describe the cranial, dental and postcranial anatomy of Periptychus carinidens based on new fossil material from the early Paleocene (Torrejonian) of New Mexico, USA. The cranial anatomy of Periptychus is broadly concurrent with the inferred plesiomorphic eutherian condition, albeit more robust in overall construction. The rostrum is moderately elongate with no constriction, the facial region is broad, and the braincase is small with a well-exposed mastoid on the posterolateral corner and tall sagittal and nuchal crests. The dentition of Periptychus is characterized by strongly crenulated enamel, enlarged upper and lower premolars with a tall centralised paracone/protoconid. The postcranial skeleton of Periptychus is that of a robust, medium-sized (~20 Kg) stout-limbed animal that was incipiently mediportal and adopted a plantigrade stance. The structure of the fore- and hindlimb of Periptychus corresponds to that of a typically terrestrial mammal, while morphological features of the forelimb such as the low tubercles of the humerus, long and prominent deltopectoral crest, pronounced medial epicondyle, and hemispherical capitulum indicate some scansorial and/or fossorial ability. Most striking is the strongly dorsoplantarly compressed astragalus of Periptychus, which in combination with the distal crus and calcaneal morphology indicates a moderately mobile cruropedal joint. The anatomy of Periptychus is unique and lacks any extant analogue; it combines a basic early placental body plan with numerous unique specializations in its dental, cranial and postcranial anatomy that exemplify the ability of mammals to adapt and evolve following catastrophic environmental upheaval
Specific phobia predicts psychopathology in young women
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90255.pdf (publisher's version ) (Closed access)Although specific phobia is characterized by an early age at onset and by high rates of comorbidity, few studies have examined comorbid relationships prospectively.
The present study investigated the association between specific phobia and the risk of a broad range of psychopathology among young women in the community.
Data came from the Dresden Predictor Study in which 1,538 German women (18-25 years) completed a diagnostic interview at two time points.
Women with specific phobia had a twofold increase in odds of developing any anxiety disorder, generalized anxiety disorder, depression, and any somatoform disorder during 17 months, compared to women without specific phobia. Except for depression, these associations persisted after adjustment for all comorbid mental disorders.
Specific phobia thus appears to be a risk factor for a variety of problems. The result further underpins the necessity for early intervention for specific phobia to prevent later mental health problems
Analytical tools used to distinguish chemical profiles of plants widely consumed as infusions and dietary supplements: artichoke, milk thistle and borututu
Artichoke, borututu and milk thistle are three medicinal plants widely consumed as infusions or included in dietary supplements (e.g., pills and syrups). Despite their high consumption, studies on nutritional value and primary metabolites are scarce, being only reported the composition in secondary metabolites such as phenolic compounds. Therefore, their nutritional value was assessed and analytical tools (liquid and gas chromatography coupled to different detectors) were used to distinguish the chemical profiles namely in hydrophilic (sugars and organic acids) and lipophilic (fatty acids and tocopherols) compounds. Chromatographic techniques are important analytical tools used in the identification and quantification of several molecules, also being a standard requirement to distinguish different profiles. Borututu gave the highest energetic value with the highest content of carbohydrates and fat, sucrose and total sugars, shikimic and citric acids, α-, β-, δ- and total tocopherols. Artichoke had the highest ash and protein contents, oxalic acid, SFA (mainly palmitic acid acid), and γ-tocopherol, as also the best n6/n3 ratio. Milk thistle showed the highest levels of fructose and glucose, quinic acid and total organic acids, PUFA, mainly linoleic acid, and the best PUFA/SFA ratio. The hydrophilic compounds identified in the studied plants, mostly sugars, are the responsible for the energetic contribution of their widely consumed infusions. Otherwise, the bioactivity of lipophilic compounds namely, unsaturated fatty acids and tocopherols, is lost in those preparations but can be recovered in dietary supplements based on the plants. As far as we know this is the first report on detailed composition of molecules with nutritional features.The authors are grateful to the Foundation for Science and Technology (FCT, Portugal) for financial support to the research centre CIMO (PEst-OE/AGR/UI0690/2011)
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