In the presence of Na(+) ions, the reaction of the ligand 2-hydroxy-1,3-bis-(3-oxo-3-(2-hydroxyphenyl)-propionyl)-benzene, H5L4, with M(AcO)2 salts (M = Mn, Co) gathers the conditions for the assembly of coordination complexes (NBu4)3[M2Na2(H2L4)3] (M = Mn(II) 1 and Co(II) 2), which exhibit a new paddle-wheel structure. The features of this new category of compounds are discussed as well as their magnetic properties and solution behaviour.
View Article and Find Full Text PDFMass casualty scenarios of radiation exposure require high throughput biological dosimetry techniques for population triage in order to rapidly identify individuals who require clinical treatment. The manual dicentric assay is a highly suitable technique, but it is also very time consuming and requires well trained scorers. In the framework of the MULTIBIODOSE EU FP7 project, semi-automated dicentric scoring has been established in six European biodosimetry laboratories.
View Article and Find Full Text PDFIndividual tagging of oocytes and embryos through the attachment of micrometer-sized polysilicon barcodes to their zona pellucida (ZP) is a promising approach to ensure their correct identification and traceability in human assisted reproduction and in animal production programs. To provide barcodes with the capacity of binding to the ZP, they must be first biofunctionalized with a biomolecule capable of binding to the ZP of both oocytes and embryos. The aim of this work was to select, among an anti-ZP2 antibody and the two lectins wheat germ agglutinin (WGA) and phytohemagglutinin-L, the most optimal biomolecule for the eventual biofunctionalization of barcodes, using mouse oocytes and embryos and commercially available microspheres as a model.
View Article and Find Full Text PDFNosemosis caused by the microsporidia Nosema apis and Nosema ceranae are among the most common pathologies affecting adult honey bees. N. apis infection has been associated with a reduced lifespan of infected bees and increased winter mortality, and its negative impact on colony strength and productivity has been described in several studies.
View Article and Find Full Text PDFObject: Accurate diagnosis of the topographical relationships of craniopharyngiomas (CPs) involving the third ventricle and/or hypothalamus remains a challenging issue that critically influences the prediction of risks associated with their radical surgical removal. This study evaluates the diagnostic accuracy of MRI to define the precise topographical relationships between intraventricular CPs, the third ventricle, and the hypothalamus.
Methods: An extensive retrospective review of well-described CPs reported in the MRI era between 1990 and 2009 yielded 875 lesions largely or wholly involving the third ventricle.
Study Question: Is the attachment of biofunctionalized polysilicon barcodes to the outer surface of the zona pellucida an effective approach for the direct tagging and identification of cultured embryos?
Summary Answer: The results achieved provide a proof of concept for a direct embryo tagging system using biofunctionalized polysilicon barcodes, which could help to minimize the risk of mismatching errors (mix-ups) in human assisted reproduction technologies.
What Is Known Already: Even though the occurrence of mix-ups is rare, several cases have been reported in fertility clinics around the world. Measures to prevent the risk of mix-ups in human assisted reproduction technologies are therefore required.
A complete isostructural series of dinuclear asymmetric lanthanide complexes has been synthesized by using the ligand 6-[3-oxo-3-(2-hydroxyphenyl)propionyl]pyridine-2-carboxylic acid (H3L). All complexes have the formula [Ln2(HL)2(H2L)(NO3)(py)(H2O)] (Ln = La (1), Ce (2), Pr (3), Nd (4), Sm (5), Eu (6), Gd (7), Tb (8), Dy (9), Ho (10), Er (11), Tm (12), Yb (13), Lu (14), Y (15); py = pyridine). Complexes of La to Yb and Y have been crystallographically characterized to reveal that the two metal ions are encapsulated within two distinct coordination environments of differing size.
View Article and Find Full Text PDFHigh-frequency Electron Paramagnetic Resonance (HFEPR) measurements have been performed on both a single-crystal and powder samples of a weakly coupled antiferromagnetic dinuclear [Mn(III)](2) molecular magnet, [Mn(III)(2)L(2)(py)(4)], where L is the trianion of 3-(3-oxo-3-phenylpropionyl)-5-methylsalicylic acid, and py is pyridine. The experimental results were analyzed on the basis of a multispin Hamiltonian using both a perturbative approach and numerical simulations. It is found that the single-crystal HFEPR results provide a direct and simple means of determining both the axial anisotropy of the individual Mn(III) ions and the isotropic exchange coupling between them.
View Article and Find Full Text PDFIn the last decade, the applicability of focus ion beam-field emission scanning electron microscopy (FIB-FESEM) in the biological field has begun to get relevance. Among the possibilities offered by FIB-FESEM, high-resolution three-dimensional (3D) reconstruction of biological structures is one of the most interesting. Using this tool, the 3D porosity of four different types of mouse oocyte zona pellucida (ZP) was analyzed.
View Article and Find Full Text PDFDevelopment of micro- and nanotechnology for the study of living cells, especially in the field of drug delivery, has gained interest in recent years. Although several studies have reported successful results in the internalization of micro- and nanoparticles in phagocytic cells, when nonphagocytic cells are used, the low internalization efficiency represents a limitation that needs to be overcome. It has been reported that covalent surface modification of micro- and nanoparticles increases their internalization rate.
View Article and Find Full Text PDFShortly after the influenza A (H1N1) 2009 pandemic began, the U.S. government provided guidance to state and local authorities to assist decision-making for the use of nonpharmaceutical strategies to minimize influenza spread.
View Article and Find Full Text PDFThe evolution of microstructure and mechanical properties of almost fully amorphous Mg(72) Zn(23) Ca(5) and crystalline Mg(70) Zn(23) Ca(5) Pd(2) alloys during immersion in Hank's balanced salt solution (HBSS), as well as their cytocompatibility, are investigated in order to assess the feasibility of both materials as biodegradable implants. Though the crystalline Mg(70) Zn(23) Ca(5) Pd(2) sample shows lower wettability and more positive corrosion potential, this sample degrades much faster upon incubation in HBSS as a consequence of the formation of micro-galvanic couples between the nobler Pd-rich dendrites and the surrounding phases. After 22-h immersion, the concentration of Mg ions in the HBSS medium containing the Mg(70) Zn(23) Ca(5) Pd(2) sample is six times larger than for Mg(72) Zn(23) Ca(5) .
View Article and Find Full Text PDFIn Europe, a network for biological dosimetry has been created to strengthen the emergency preparedness and response capabilities in case of a large-scale nuclear accident or radiological emergency. Through the RENEB (Realising the European Network of Biodosimetry) project, 23 experienced laboratories from 16 European countries will establish a sustainable network for rapid, comprehensive and standardised biodosimetry provision that would be urgently required in an emergency situation on European ground. The foundation of the network is formed by five main pillars: (1) the ad hoc operational basis, (2) a basis of future developments, (3) an effective quality-management system, (4) arrangements to guarantee long-term sustainability and (5) awareness of the existence of RENEB.
View Article and Find Full Text PDFA rapid cancer cell detection and quantification assay, based on the electrocatalytic properties of gold nanoparticles towards the hydrogen evolution reaction, is described. The selective labeling of cancer cells is performed in suspension, allowing a fast interaction between the gold nanoparticle labels and the target proteins expressed at the cell membrane. The subsequent electrochemical detection is accomplished with small volumes of sample and user-friendly equipment through a simple electrochemical method that generates a fast electrochemical response used for the quantification of nanoparticle-labeled cancer cells.
View Article and Find Full Text PDFHere we present a new strategy for a simple and fast detection of cancer circulating cells (CTCs) using nanoparticles. The human colon adenocarcinoma cell line (Caco2) was chosen as a model CTC. Similarly to other adenocarcinomas, colon adenocarcinoma cells have a strong expression of EpCAM, and for this reason this glycoprotein was used as the capture target.
View Article and Find Full Text PDFEl propósito de este trabajo es presentar el impacto y la integración que los conocimientos adquiridos en el Programa Internacional de Formación en Ética de la Investigación Biomédica y Psicosocial de la Universidad de Chile han tenido en mi experiencia profesional, en el ámbito de la investigación psicosocial en un Instituto de Salud de México. Para este objetivo, expondré tres áreas en las cuales se ha podido evidenciar tal impacto: trabajo en los comités de ética, desarrollo de programas de académicos en bioética e investigación y publicación sobre ética y bioética. El motivo que me llevó a incursionar en el Programa fue que su enseñanza vincula la investigación psicosocial con la ética y la bioética, lo cual me permitió dirigir este tipo de reflexión hacia problemas como violencia, suicidio, adicciones, depresión y salud mental, y a nuevos campos como los estudios comunitarios, con poblaciones en riesgo o vulnerables, en los cuales las diversas implicaciones son difíciles de indagar.
View Article and Find Full Text PDFMurine models of Alzheimer's disease (AD) provide means to detect and follow biomarker changes similar to those observed in humans. Non-invasive biomarkers, such as those provided by magnetic resonance imaging (MRI) and spectroscopy (MRS) methods are highly desirable, however, systematic studies of in vivo MRI/MRS methods to characterize the cerebral morphology and metabolic pattern of these mice remain scarce. We investigated sixteen consecutive slices from the brain of wild-type and AβPP/PS1 mice, obtaining a collection of T2 weighted, diffusion weighted and magnetization transfer weighted images as well as 1H PRESS spectra from the cortical and subcortical areas.
View Article and Find Full Text PDFContext: Adolescence marks a time when many young people engage in risky behaviors with potential implications for long-term health. Interventions focused on adolescents' parents and other caregivers have the potential to affect adolescents across a variety of risk and health-outcome areas.
Evidence Acquisition: Community Guide methods were used to evaluate the effectiveness of caregiver-targeted interventions in addressing adolescent risk and protective behaviors and health outcomes.
J Mech Behav Biomed Mater
February 2012
The influence of partial substitution of Mg by Pd on the microstructure, mechanical properties and corrosion behaviour of Mg(72-x)Zn(23)Ca(5)Pd(x) (x=0, 2 and 6 at.%) alloys, synthesized by copper mould casting, is investigated. While the Mg(72)Zn(23)Ca(5) alloy is mainly amorphous, the addition of Pd decreases the glass-forming ability, thus favouring the formation of crystalline phases.
View Article and Find Full Text PDFGiven the key role played by honey bees in almost all terrestrial ecosystems, maintaining bee populations in adequate sanitary conditions is crucial for these essential pollinators to continue their work. From the beginning of the 21st century, beekeepers have reported a progressive increase in the overwintering mortality of honey bee colonies worldwide. Despite the failure to reach a consensus regarding the cause of this phenomenon, pathogens are thought to be strongly implicated.
View Article and Find Full Text PDFKnowledge on colonization modes and interplant movement of Nasonovia ribisnigri can contribute to the development of optimal control of this pest. The aim of this study was to determine the spatio-temporal distribution and the mode of spread between adult morphs of Nasonovia ribisnigri, comparing spring and autumn lettuce protected crops. The spatial and temporal pattern was analyzed using the spatial analysis by distance indices (SADIE) methodology and other related displacement indices.
View Article and Find Full Text PDFAnnu Int Conf IEEE Eng Med Biol Soc
June 2012
Interventional radiologists and staff members are frequently exposed to the effects of direct and scattered radiation, which undergo in deterministic effects (radiodermitis, aged skin, cataracts, telangiectasia in nasal region, vasocellular epitelioms, hands depilation) and/or stochastic ones (cancer incidence). A methodology has been proposed for estimating the radiation risk or detriment from a group of six exposed interventional radiologists of the Hospital Universitario La Fe (Valencia, Spain), which had developed general exposition symptoms attributable to deterministic effects of ionizing radiation. Equivalent doses have been periodically registered using termoluminiscence dosimeters (TLD's) and wrist dosimeters, H(p)(10) and H(p)(0.
View Article and Find Full Text PDFMicrosporidiosis of adult honeybees caused by Nosema apis and Nosema ceranae is a common worldwide disease with negative impacts on colony strength and productivity. Few options are available to control the disease at present. The role of the queen in bee population renewal and the replacement of bee losses due to Nosema infection is vital to maintain colony homeostasis.
View Article and Find Full Text PDFAn extended polypyrazolyl ligand has been used to assemble Mn ions into high spin entities, in the form of one stable molecule composed of two well defined clusters. The slow relaxation of the magnetisation observed is demonstrated to arise from each "half-SMM" composing this molecular cluster pair.
View Article and Find Full Text PDFWe show that a chemically engineered structural asymmetry in [Tb2] molecular clusters renders the two weakly coupled Tb3+ spin qubits magnetically inequivalent. The magnetic energy level spectrum of these molecules meets then all conditions needed to realize a universal CNOT quantum gate. A proposal to realize a SWAP gate within the same molecule is also discussed.
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