74 research outputs found
Influence of the Ligand Alkyl Chain Length on the Solubility, Aqueous Speciation, and Kinetics of Substitution Reactions of Water- Soluble M3S4 (M = Mo, W) Clusters Bearing Hydroxyalkyl Diphosphines
Water-soluble [M3S4X3(dhbupe)3]+ diphosphino complexes (dhbupe = 1,2-bis(bis(hydroxybutyl)phosphino)ethane), 1+ (M = Mo, X = Cl) and 2+ (M = W; X = Br), have been synthesized by extending the procedure used for the preparation of their hydroxypropyl analogues by reaction of the M3S4(PPh3)3X4(solvent)x molecular clusters with the corresponding 1,2-bis- (bishydroxyalkyl)diphosphine. The solid state structure of the [M3S4X3(dhbupe)3]+ cation possesses a C3 symmetry with a cuboidal M3S4 unit, and the outer positions are occupied by one halogen and two phosphorus atoms of the diphosphine ligand. At a basic pH, the halide ligands are substituted by hydroxo groups to afford the corresponding [Mo3S4(OH)3(dhbupe)3]+ (1OH +) and [W3S4(OH)3(dhbupe)3]+ (2OH +) complexes. This behavior is similar to that found in 1,2-bis(bis(hydroxymethyl)phosphino)ethane (dhmpe) complexes and differs from that observed for 1,2-bis(bis(hydroxypropyl)phosphino)ethane (dhprpe) derivatives. In the latter case, an alkylhydroxo group of the functionalized diphosphine replaces the chlorine ligands to afford Mo3S4 complexes in which the deprotonated dhprpe acts in a tridentate fashion. Detailed studies based on stopped-flow, 31P{1H} NMR, and electrospray ionization mass spectrometry techniques have been carried out in order to understand the solution behavior and kinetics of interconversion between the different species formed in solution: 1 and 1OH + or 2 and 2OH
+. On the basis of the kinetic results, a mechanism with two parallel reaction pathways involving water and OH− attacks is proposed for the formal substitution of halides by hydroxo ligands. On the other hand, reaction of the hydroxo clusters with HX acids occurs with protonation of the OH− ligands followed by substitution of coordinated water by X−
CDAPubMed: a browser extension to retrieve EHR-based biomedical literature
Over the last few decades, the ever-increasing output of scientific publications has led to new challenges to keep up to date with the literature. In the biomedical area, this growth has introduced new requirements for professionals, e.g., physicians, who have to locate the exact papers that they need for their clinical and research work amongst a huge number of publications. Against this backdrop, novel information retrieval methods are even more necessary. While web search engines are widespread in many areas, facilitating access to all kinds of information, additional tools are required to automatically link information retrieved from these engines to specific biomedical applications. In the case of clinical environments, this also means considering aspects such as patient data security and confidentiality or structured contents, e.g., electronic health records (EHRs). In this scenario, we have developed a new tool to facilitate query building to retrieve scientific literature related to EHRs. Results: We have developed CDAPubMed, an open-source web browser extension to integrate EHR features in biomedical literature retrieval approaches. Clinical users can use CDAPubMed to: (i) load patient clinical documents, i.e., EHRs based on the Health Level 7-Clinical Document Architecture Standard (HL7-CDA), (ii) identify relevant terms for scientific literature search in these documents, i.e., Medical Subject Headings (MeSH), automatically driven by the CDAPubMed configuration, which advanced users can optimize to adapt to each specific situation, and (iii) generate and launch literature search queries to a major search engine, i.e., PubMed, to retrieve citations related to the EHR under examination. Conclusions: CDAPubMed is a platform-independent tool designed to facilitate literature searching using keywords contained in specific EHRs. CDAPubMed is visually integrated, as an extension of a widespread web browser, within the standard PubMed interface. It has been tested on a public dataset of HL7-CDA documents, returning significantly fewer citations since queries are focused on characteristics identified within the EHR. For instance, compared with more than 200,000 citations retrieved by breast neoplasm, fewer than ten citations were retrieved when ten patient features were added using CDAPubMed. This is an open source tool that can be freely used for non-profit purposes and integrated with other existing systems
Cloud Computing Service for Managing Large Medical Image Data-Sets Using Balanced Collaborative Agents
Managing large medical image collections is an increasingly demanding important issue in many hospitals and other medical settings. A huge amount of this information is daily generated, which requires robust and agile systems. In this paper we present a distributed multi-agent system capable of managing very large medical image datasets. In this approach, agents extract low-level information from images and store them in a data structure implemented in a relational database. The data structure can also store semantic information related to images and particular regions. A distinctive aspect of our work is that a single image can be divided so that the resultant sub-images can be stored and managed separately by different agents to improve performance in data accessing and processing. The system also offers the possibility of applying some region-based operations and filters on images, facilitating image classification. These operations can be performed directly on data structures in the database
El arte rupestre galaico: una reflexión crítica sobre el presente y una propuesta para el futuro
In the paper it is proposed a management standard for the Galician Rock Art having as basic idea the determination and evaluation of Heritage and, then, to work on it in order to a more effective protection and better social profitabily. General protective measures are considered and deep actions on the scientifically and socially most outstanding units are suggested.En el artículo se pasa revista a los principales problemas de conservación que afectan a los grabados rupestres galaicos y se propone un Plan de Gestión de los mismos. La idea básica es que se determina un Patrimonio, se evalúa y se actúa sobre el mismo para obtener una protección más efectiva y una mayor rentabilización social. Se sugieren acciones profundas sobre conjuntos relevantes y significativos científica y socialmente
El arte rupestre galaico: una reflexión crítica sobre el presente y una propuesta para el futuro
Cycloaddition of alkynes to diimino Mo3S4 cubane-type clusters: a combined experimental and theoretical approach
A heterocyclic ligand 4,40-di-tert-butyl-2,20-bipyridine (dbbpy) has been coordinated to the Mo3S4 cluster unit affording the complex [Mo3S4Cl3(dbbpy)3]+ ([1]+) in a one-step ligand-exchange protocol from [Mo3S4(tu)8(H2O)]Cl4 4H2O (tu = thiourea). The new cluster was isolated as [1]PF6 and [1]Cl salts in high yields and the crystal structure of the latter determined by X-ray analysis. The synthetic procedure was extended to tungsten to afford [W3S4Cl3(dbbpy)3]+ ([2]+). Kinetic and NMR studies show that [1]+ reacts with several alkynes to form dithiolene species via concerted [3+2] cycloaddition reactions whereas [2]+ remains inert under similar conditions. The different rates for the reactions of [1]+ are rationalised by computational (DFT) calculations, which show that the more electron-withdrawing the substituents of the alkyne the faster the reaction. The inertness of [2]+ is due to the endergonicity of its reactions, which feature DGr values systematically 5–7 kcal mol 1 more positive than for those of [1]+
Accessing and managing open medical resources in Africa over the Internet
Recent commentaries have proposed the advantages of using open exchange of data and informatics resources for improving health-related policies and patient care in Africa. Yet, in many African regions, both private medical and public health information systems are still unaffordable. Open exchange over the social Web 2.0 could encourage more altruistic support of medical initiatives. We have carried out some experiments to demonstrate the feasibility of using this approach to disseminate open data and informatics resources in Africa. After the experiments we developed the AFRICA BUILD Portal, the first Social Network for African biomedical researchers. Through the AFRICA BUILD Portal users can access in a transparent way to several resources. Currently, over 600 researchers are using distributed and open resources through this platform committed to low connections
Ligand diversity contributes to the full activation of the jasmonate pathway in Marchantia polymorpha
In plants, jasmonate signaling regulates a wide range of processes from growth and development to defense responses and thermotolerance. Jasmonates, such as jasmonic acid (JA), (+)-7-iso-jasmonoyl-l-isoleucine (JA-Ile), 12-oxo-10,15(Z)-phytodienoic acid (OPDA), and dinor-12-oxo-10,15(Z)-phytodienoic acid (dn-OPDA), are derived from C18 (18 Carbon atoms) and C16 polyunsaturated fatty acids (PUFAs), which are found ubiquitously in the plant kingdom. Bryophytes are also rich in C20 and C22 long-chain polyunsaturated fatty acids (LCPUFAs), which are found only at low levels in some vascular plants but are abundant in organisms of other kingdoms, including animals. The existence of bioactive jasmonates derived from LCPUFAs is currently unknown. Here, we describe the identification of an OPDA-like molecule derived from a C20 fatty acid (FA) in the liverwort Marchantia polymorpha (Mp), which we term (5Z,8Z)-10-(4-oxo-5-((Z)-pent-2-en-1-yl)cyclopent-2-en-1-yl)deca-5,8-dienoic acid (C20-OPDA). This molecule accumulates upon wounding and, when applied exogenously, can activate known Coronatine Insensitive 1 (COI1) -dependent and -independent jasmonate responses. Furthermore, we identify a dn-OPDA-like molecule (Δ4-dn-OPDA) deriving from C20-OPDA and demonstrate it to be a ligand of the jasmonate coreceptor (MpCOI1-Mp Jasmonate-Zinc finger inflorescence meristem domain [MpJAZ]) in Marchantia. By analyzing mutants impaired in the production of LCPUFAs, we elucidate the major biosynthetic pathway of C20-OPDA and Δ4-dn-OPDA. Moreover, using a double mutant compromised in the production of both Δ4-dn-OPDA and dn-OPDA, we demonstrate the additive nature of these molecules in the activation of jasmonate responses. Taken together, our data identify a ligand of MpCOI1 and demonstrate LCPUFAs as a source of bioactive jasmonates that are essential to the immune response of M. polymorpha.Peer reviewe
Ocupación humana y monumentalidad durante la Prehistoria Reciente en el islote de Guidoiro Areoso (Ría de Arousa, Pontevedra): investigaciones en el marco de las dinámicas litorales atlánticas actuales
Socio-geographical disparities of obesity and excess weight in adults in Spain: insights from the ENE-COVID study
Background: In Spain, differences in the prevalence of obesity and excess weight according to sex and sociodemographic factors have been described at the national level, although current data do not allow to delve into geographical differences for these conditions. The aim was to estimate national and regional prevalences of adult obesity and excess weight in Spain by sex and sociodemographic characteristics, and to explore difference sources of inequalities in its distribution, as well as its geographical pattern. Method: ENE-COVID study was a nationwide representative seroepidemiological survey with 57,131 participants. Residents in 35,893 households were selected from municipal rolls using a two-stage random sampling stratified by province and municipality size (April-June 2020). Participants (77.0% of contacted individuals) answered a questionnaire which collected self-reported weight and height, as well as different socioeconomic variables, that allowed estimating crude and standardized prevalences of adult obesity and excess weight. Results: Crude prevalences of obesity and excess weight were higher in men (obesity: 19.3% vs. 18.0%; excess weight: 63.7% vs. 48.4%), while severe obesity was more prevalent in women (4.5% vs. 5.3%). These prevalences increased with age and disability, and decreased with education, census tract income and municipality size. Differences by educational level, relative census income, nationality or disability were clearly higher among women. Obesity by province ranged 13.3-27.4% in men and 11.4-28.1% in women; excess weight ranged 57.2-76.0% in men and 38.9-59.5% in women. The highest prevalences were located in the southern half of the country and some north-western provinces. Sociodemographic characteristics only explained a small part of the observed geographical variability (25.2% obesity). Conclusion: Obesity and overweight have a high prevalence in Spain, with notable geographical and sex differences. Socioeconomic inequalities are stronger among women. The observed geographical variability suggests the need to implement regional and local interventions to effectively address this public health problem.This study was supported by Spanish Ministry of Health, Institute of Health Carlos III, and Spanish National Health System.S
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