75 research outputs found

    Crocodylomorph eggs and eggshells from the Lourinhã Fm. (Upper Jurassic), Portugal

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    We here present fossil crocodylomorpha eggshells from the Late Jurassic Lourinhã Formation of Portugal, recovered from five sites: one nest from Cambelas and various fragments from Casal da Rola, Paimogo I, Paimogo II, and Peralta. The nest is composed of 13 eggs and is the only sample not found in association with dinosaur egg material. Our research reveals that on a micro- and ultrastructural analysis, all our samples present the typical characters consistent with crocodiloid eggshell morphotype, such as the shell unit shape, the organization of the eggshell layers, and the triangular blocky extinction observed with crossed nicols. We assign the material from the Lourinhã Formation to the oofamily Krokolithidae, making it the oldest crocodylomorph eggs known so far, as well as the best record for eggs of non-crocodylian crocodylomorphs. Furthermore, our study indicates that the basic structure of crocodilian eggshells has remained stable since at least the Late Jurassic

    Two new ootaxa from the late Jurassic::The oldest record of crocodylomorph eggs, from the Lourinha Formation, Portugal

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    <div><p>The Late Jurassic Lourinhã Formation is known for its abundant remains of dinosaurs, crocodylomorphs and other vertebrates. Among this record are nine localities that have produced either dinosaur embryos, eggs or eggshell fragments. Herein, we describe and identify the first crocodiloid morphotype eggs and eggshells from the Lourinhã Formation, from five occurrences. One clutch from Cambelas, composed of 13 eggs, eggshell fragments from Casal da Rola and Peralta, one crushed egg and eggshells from Paimogo North, and four crushed eggs as well as eggshell fragments from Paimogo South. We observed and confirmed diagnostic morphological characters for crocodiloid eggshells and which are consistent with a crocodylomorph affinity, such as the ellipsoidal shape, wedge-shaped shell units, triangular extinction under cross-polarized light, and tabular ultrastructure. This material is distinctive enough to propose two new ootaxa within the oofamily Krokolithidae, <i>Suchoolithus portucalensis</i>, oogen. and oosp. nov., for the material from Cambelas, the most complete clutch known for crocodiloid eggs, and <i>Krokolithes dinophilus</i>, oosp. nov., for the remaining material. These are the oldest crocodylomorph eggs known, extending the fossil record for this group to the Late Jurassic. Furthermore, except for the clutch from Cambelas, the material was found with theropod eggs and nests, in the other four occurrences, which seem to suggest some form of biological relationship, still unclear at this point.</p></div

    Predicción mediante productos de distorsión de hipoacusia en trabajadores expuestos al ruido en el Hospital General Universitario Gregorio Marañon

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    La Hipoacusia inducida por ruido se define como la disminución de la capacidad auditiva de uno o ambos oídos, parcial o total, permanente y acumulativa, de tipo neurosensorial que se origina gradualmente, durante y como resultado de la exposición a niveles perjudiciales de ruido en el ambiente laboral, de tipo continuo o intermitente de intensidad relativamente alta (> 85 dB) durante un periodo prolongado de tiempo.En España el ruido es el contaminante ambiental más frecuente encontrado en el conjunto de todos los sectores de la actividad, según las estadísticas de enfermedades profesionales declaras ante el ministerio de trabajo en los últimos 10 años, ocupa el tercer lugar de frecuencia después de la tendinopatias por sobre uso y neuropatías periféricassecundarias presión (10).En la actualidad el diagnóstico y seguimiento de los trabajadores expuesto al ruido se realiza con la audiometría, considerada como Prueba Gold estándar (19), a pesar de esto presenta desventajas importantes como son, la subjetividad en el momento de realizar la prueba, depender en gran parte de la respuesta dada por el paciente, al igual que de la calidad del equipo. Siendo muy útil para el diagnóstico de la hipoacusia(instaurada), el paciente que presente pérdida auditiva diagnosticada a través de este método, en el caso de la hipoacusia por ruido, no serán reversibles..

    In vivo quantitative lipidic map of brown adipose tissue by chemical shift imaging at 4.7 tesla

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    In the present paper, chemical shift imaging techniques are applied to quantitative in vivo evaluation of fat and water content in interscapular brown adipose tissue (BAT). The experiments have been carried out on five female Sprague-Dawley rats after calibration and testing with suitable phantoms containing known amounts of water and oil. We found that, in the interscapular BAT, the fat is about 50% at the surface (mainly unilocular) region, but its percentage drops to 20–30% in the deepest (mainly multilocular) portion. The perirenal deposits of white adipose tissue (WAT) contained significantly higher amount of fat with large areas ranging from 70 to 90%. Later the rats were killed and the same procedure was repeated with dead animals. Experiments performed in dead rats show a modification of the hydro-lipidic ratio more evident in the multilocular portions of the deposit. The present work demonstrates that MRI-based methods allow a non-invasive, in vivo quantitative mapping of the lipid content which can be applied to investigation of brown adipose tissue deposits in small experiment animals.—Lunati, E., P. Marzola, E. Nicolato, M. Fedrigo, M. Villa, and A. Sbarbati. In vivo quantitative lipidic map of brown adipose tissue by chemical shift imaging at 4.7 tesla. J. Lipid Res. 1999. 40: 1395–1400

    Phenomenology of a Fake Inert Doublet Model

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    We introduce a new way of modeling the physics beyond the Standard Model by considering fake, strictly off-shell degrees of freedom: the fakeons. To demonstrate the approach and exemplify its reach, we re-analyze the phenomenology of the Inert Doublet Model under the assumption that the second doublet is a fakeon. Remarkably, the fake doublet avoids the most stringent ZZ-pole constraints regardless of the chosen mass scale, thereby allowing for the presence of new effects well below the electroweak scale. Furthermore, the absence of on-shell propagation prevents fakeons from inducing missing energy signatures in collider experiments. The distinguishing features of the model appear at the loop level, where fakeons modify the Higgs boson hγγh\to\gamma\gamma decay width and the Higgs trilinear coupling. The running of Standard Model parameters proceeds as in the usual Inert Doublet Model case. Therefore, the fake doublet can also ensure the stability of the Standard Model vacuum. Our work shows that fakeons are a valid alternative to the usual tools of particle physics model building, with the potential to shape a new paradigm, where the significance of the existing experimental constraints towards new physics must necessarily be reconsidered.Comment: 12 pages, 7 figures, version accepted by JHE

    Co-Transplantation of endothelial progenitor cells and pancreatic islets to induce long-lasting normoglycemia in streptozotocin-treated diabetic rats

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    Graft vascularization is a crucial step to obtain stable normoglycemia in pancreatic islet transplantation. Endothelial progenitor cells (EPCs) contribute to neoangiogenesis and to the revascularization process during ischaemic events and play a key role in the response to pancreatic islet injury. In this work we co-transplanted EPCs and islets in the portal vein of chemically-induced diabetic rats to restore islet vascularization and to improve graft survival. Syngenic islets were transplanted, either alone or with EPCs derived from green fluorescent protein (GFP) transgenic rats, into the portal vein of streptozotocin-induced diabetic rats. Blood glucose levels were monitored and intraperitoneal glucose tolerance tests were performed. Real time-PCR was carried out to evaluate the gene expression of angiogenic factors. Diabetic-induced rats showed long-lasting (6 months) normoglycemia upon co-transplantation of syngenic islets and EPCs. After 3–5 days from transplantation, hyperglycaemic levels dropped to normal values and lasted unmodified as long as they were checked. Further, glucose tolerance tests revealed the animals' ability to produce insulin on-demand as indexed by a prompt response in blood glucose clearance. Graft neovascularization was evaluated by immunohistochemistry: for the first time the measure of endothelial thickness revealed a donor-EPC-related neovascularization supporting viable islets up to six months after transplant. Our results highlight the importance of a newly formed viable vascular network together with pancreatic islets to provide de novo adequate supply in order to obtain enduring normoglycemia and prevent diabetes-related long-term health hazards

    Nanoparticles exhibiting self-regulating temperature as innovative agents for Magnetic Fluid Hyperthermia

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    During the last few years, for therapeutic purposes in oncology, considerable attention has been focused on a method called magnetic fluid hyperthermia (MFH) based on local heating of tumor cells. In this paper, an innovative, promising nanomaterial, M48 composed of iron oxide-based phases has been tested. M48 shows self-regulating temperature due to the observable second order magnetic phase transition from ferromagnetic to paramagnetic state. A specific hydrophilic coating based on both citrate ions and glucose molecules allows high biocompatibility of the nanomaterial in biological matrices and its use in vivo. MFH mediator efficiency is demonstrated in vitro and in vivo in breast cancer cells and tumors, confirming excellent features for biomedical application. The temperature increase, up to the Curie temperature, gives rise to a phase transition from ferromagnetic to paramagnetic state, promoting a shortage of the r2 transversal relaxivity that allows a switch in the contrast in Magnetic Resonance Imaging (MRI). Combining this feature with a competitive high transversal (spin-spin) relaxivity, M48 paves the way for a new class of temperature sensitive T2 relaxing contrast agents. Overall, the results obtained in this study prepare for a more affordable and tunable heating mechanism preventing the damages of the surrounding healthy tissues and, at the same time, allowing monitoring of the temperature reached

    Learning approach to analyze tumour heterogeneity in DCE-MRI data during anti-cancer treatment

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    The paper proposes a learning approach to support medical researchers in the context of in-vivo cancer imaging, and specifically in the analysis of Dynamic Contrast-Enhanced MRI (DCE-MRI) data. Tumour heterogeneity is characterized by identifying regions with different vascular perfusion. The overall aim is to measure volume differences of such regions for two experimental groups: the treated group, to which an anticancer therapy is administered, and a control group. The proposed approach is based on a three-steps procedure: (i) robust features extraction from raw time-intensity curves, (ii) sample-regions identification manually traced by medical researchers on a small portion of input data, and (iii) overall segmentation by training a Support Vector Machine (SVM) to classify the MRI voxels according to the previously identified cancer areas. In this way a non-invasive method for the analysis of the treatment efficacy is obtained as shown by the promising results reported in our experiments. © 2009 Springer Berlin Heidelberg

    Vaccination adjuvated against hepatitis B in Spanish National Healthcare System (SNS) workers typed as non-responders to conventional vaccines

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    [EN] Trial Design: An interventional, phase 4, single group assignment, without masking (open label), preventive clinical trial was carried out in health workers with biological risk in their tasks, who have been filed as non-responders to conventional vaccination against Hepatitis B. Methods: 67 health workers with biological risk in their tasks, who have been filed as non-responders to conventional vaccination against Hepatitis B, were enrolled in the Clinical Trial. All participants were from 18 years up to 64 years old. Inclusion Criteria: NHS workers -including university students doing their internships in health centres dependent on the National Health System (inclusion of students is regulated and limited by specific instructions on labour prevention in each autonomous community)- classified as non-responders. The criteria defining them as non-responders to the conventional hepatitis B vaccine is anti HBsAb titers < 10 mUI/ml following the application of six doses of conventional vaccine at 20 lg doses (two complete guidelines). The objective of this study was to provide Health workersstaff with an additional protection tool against hepatitis B infection, and to evaluate the efficacy of the adjuvanted vaccine in healthy non-responders to conventional hepatitis B vaccine. The primary outcome was the measurement of antibody antiHBs before the first Fendrix dose and a month after the administration of each dose. Other outcome was collection of adverse effects during administration and all those that could be related to the vaccine and that occur within 30 days after each dose. In this study, only one group was assigned. There was no randomization or masking. Results: The participants were recruited between April 13, 2018 and October 31, 2019. 67 participants were enrolled in the Clinical Trial and included the analyses. The primary immunisation consists of 4 separate 0.5 ml doses of Fendrix , administered at the following schedule: 1 month, 2 months and 6 months from the date of the first dose. Once the positivity was reached in any of the doses, the participant finished the study and was not given the following doses. 68.66% (46 out 67) had a positive response to first dose of Fendrix. 57.14% (12 out 21) had a positive response to second dose of Fendrix . 22.22% (2 out 9) had a positive response to third dose of Fendrix and 42.96% (3 out 7) had a positive response to last dose of Fendrix. Overall, 94.02% (64 out 67) of participants had a positive response to Fendrix . No serious adverse event occurred. Conclusions: The use of Fendrix , is a viable vaccine alternative for NHS workers classified as ‘‘nonresponders”. Revaccination of healthy non-responders with Fendrix, resulted in very high proportions of responders without adverse events. Trial registration: The trial was registered in the Spanish National Trial Register (REEC), ClinicalTrials.gov and inclusion has been stopped (identifier NCT03410953; EudraCT-number 2016-004991-23). Funding: GRS 1360/A/16: Call for aid for the financing of research projects in biomedicine, health management and socio-health care to be developed in the centres of the Regional Health Management of Autonomous Community of Castile-Leon. In addition, this work has been supported by the Spanish Platform for Clinical Research and Clinical Trials, SCReN (Spanish Clinical Research Network), funded by the Subdirectorate General for Research Evaluation and Promotion of the Carlos III Health Institute (ISCIII), through the project PT13/0002/0039 and project PT17/0017/0023 integrated in the State Plan for R&D&I 2013–2016 and co-financed by and the European Regional Development Fund (ERDF)

    PEG-capped, lanthanide doped GdF3 nanoparticles: luminescent and T-2 contrast agents for optical and MRI multimodal imaging

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    A facile method for the synthesis of water dispersible Er3+/Yb3+ and Tm3+/Yb3+ doped upconverting GdF3 nanoparticles is reported. Strong upconversion emissions are observed in the red (for Er/Yb doped) and near-infrared (for Tm/Yb doped) regions upon laser excitation at 980 nm. The PEG coating ensures a good dispersion of the system in water and reduces the radiationless de-excitation of the excited states of the Er3+ and Tm3+ ions by water molecules. The r(2) relaxivity values are quite high with respect to the common T-2-relaxing agents (22.6 +/- 3.4 mM(-1) s(-1) and 15.8 +/- 3.4 mM(-1) s(-1) for the Tm/Yb and Er/Yb doped samples, respectively), suggesting that the present NPs can be interesting as T-2 weighted contrast agents for proton MRI purpose. Preliminary experiments conducted in vitro, in stem cell cultures, and in vivo, after subcutaneous injection of the lanthanide-doped GdF3 NPs, indicate scarce toxic effects. After an intravenous injection in mice, the GdF3 NPs localize mainly in the liver. The present results indicate that the present Er3+/Yb3+ and Tm3+/Yb3+ doped GdF3 NPs are suitable candidates to be efficiently used as bimodal probes for both in vitro and in vivo optical and magnetic resonance imaging
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