20 research outputs found

    Elliptical Halbach magnet and gradient modules for low-field portable MRI

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    Objective. To develop methods to design the complete magnetic system for a truly portable MRI scanner for neurological and musculoskeletal (MSK) applications, optimized for field homogeneity, field of view (FoV) and gradient performance compared to existing low-weight configurations. Approach. We explore optimal elliptic-bore Halbach configurations based on discrete arrays of permanent magnets. In this way, we seek to improve the field homogeneity and remove constraints to the extent of the gradient coils typical of Halbach magnets. Specifically, we have optimized a tightly-packed distribution of magnetic Nd2_2Fe14_14B cubes with differential evolution algorithms, and a second array of shimming magnets with interior point and differential evolution methods. We have also designed and constructed an elliptical set of gradient coils that extend over the whole magnet length, maximizing the distance between the lobe centers. These are optimized with a target field method minimizing a cost function that considers also heat dissipation. Main result. We have employed the new toolbox to build the main magnet and gradient modules for a portable MRI scanner designed for point-of-care and residential use. The elliptical Halbach bore has semi-axes of 10 & 14 cm and the magnet generates a field of 87 mT homogeneous down to 5,700 ppm (parts per million) in a 20 cm diameter FoV, it weighs 216 kg and has a width of 65 cm and a height of 72 cm. Gradient efficiencies go up to around 0.8 mT/m/A, for a maximum of 12 mT/m with in 0.5 ms with 15 A & 15 V amplifier. The distance between lobes is 28 cm, significantly increased with respect to other Halbach-based scanners. Heat dissipation is around 25 W at maximum power, and gradient deviations from linearity are below 20% in a 20 cm sphere

    The Jak2 Pathway Is Activated In Idiopathic Pulmonary Fibrosis

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    Background: Idiopathic pulmonary fibrosis (IPF) is the most rapidly progressive and fatal fibrotic disorder, with no curative therapies. The signal transducer and activator of transcription 3 (STAT3) protein is activated in lung fibroblasts and alveolar type II cells (ATII), thereby contributing to lung fibrosis in IPF. Although activation of Janus kinase 2 (JAK2) has been implicated in proliferative disorders, its role in IPF is unknown. The aim of this study was to analyze JAK2 activation in IPF, and to determine whether JAK2/STAT3 inhibition is a potential therapeutic strategy for this disease. Methods and results: JAK2/p-JAK2 and STAT3/pSTAT3 expression was evaluated using quantitative real time-PCR, western blotting, and immunohistochemistry. Compared to human healthy lung tissue (n = 10) both proteins were upregulated in the lung tissue of IPF patients (n = 12). Stimulating primary ATII and lung fibroblasts with transforming growth factor beta 1 or interleukin (IL)-6/IL-13 activated JAK2 and STAT3, inducing epithelial to mesenchymal and fibroblast to myofibroblast transitions. Dual p-JAK2/p-STAT3 inhibition with JSI-124 or silencing of JAK2 and STAT3 genes suppressed ATII and the fibroblast to myofibroblast transition, with greater effects than the sum of those obtained using JAK2 or STAT3 inhibitors individually. Dual rather than single inhibition was also more effective for inhibiting fibroblast migration, preventing increases in fibroblast senescence and Bcl-2 expression, and ameliorating impaired autophagy. In rats administered JSI-124, a dual inhibitor of p-JAK2/p-STAT3, at a dose of 1 mg/kg/day, bleomycin-induced lung fibrosis was reduced and collagen deposition in the lung was inhibited, as were JAK2 and STAT3 activation and several markers of fibrosis, autophagy, senescence, and anti-apoptosis. Conclusions: JAK2 and STAT3 are activated in IPF, and their dual inhibition may be an attractive strategy for treating this disease

    First data about the status of the Cabrera vole Iberomys cabrerae (Thomas, 1906) in Castelló and the expansion of its distribution to the south of the province of València

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    Se registra por primera vez en la provincia de Castelló el topillo de Cabrera Iberomys cabrerae (Thomas, 1906) en tiempos recientes, donde tan solo se contaba con registro fósil en varios yacimientos datados en el Neolítico. Además se amplía hacia el sur su distribución conocida en València. Se describe y comenta su descubrimiento en la sierra del Toro (l'Alt Palància) y en la Font de la Figuera (la Costera).This is the first recorded finding in recent times of the Cabrera vole Iberomys cabrerae (Thomas, 1906) in Castelló province, where previously only fossil records have been identified in several Neolithic sites. In addition, it's known distribution is expanded to the south of the province of València. These discoveries, made in the Sierra del Toro (l'Alt Palància) and la Font de la Figuera (la Costera), are described and commented upon.Este estudio ha sido financiado por el Servicio de Vida Silvestre de la Conselleria de Agricultura, Medio Ambiente, Cambio Climático y Desarrollo Rural de la Generalitat Valenciana

    Synthesis and evaluation of fluorimetric and colorimetric chemosensors for anions based on (oligo)thienyl-thiosemicarbazones

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    A family of heterocyclic thiosemicarbazone dyes (3a-d) containing thienyl groups has been synthesized, characterized and their chromo-fluorogenic response in acetonitrile in the presence of selected anions studied. Acetonitrile solutions of 3a-d show absorption bands in the 338-425 nm range which are modulated by the groups attached to the thiosemicarbazone moiety. The fluoride, chloride, bromide, iodide, dihydrogen phosphate, hydrogen sulfate, nitrate, acetate and anions were used in the recognition studies. Only sensing features were observed for fluoride, cyanide, acetate and dihydrogen phosphate anions. Two different chromogenic responses were found, (i) a small shift of the absorption band due to coordination of the anions with the thiourea protons and (ii) the appearance of a new red shifted band due to deprotonation of the receptor. For the latter process changes in the color solutions from pale-yellow to orange-red were observed. Fluorescence studies showed a different emission behavior according to the number of thienyl rings in the π-conjugated bridges. Stability constants for the two processes (complex formation + deprotonation) for receptors 3a-d in the presence of fluoride and acetate anions were determined from spectrophotometric titrations using the HypSpec program. The interaction of 3d with fluoride was also studied through 1H NMR titrations. Semiempirical calculations to evaluate the hydrogen-donating ability of the receptors were also performed.Fundação para a Ciência e a Tecnologia (FCT) , Acções Integradas Luso-Espanholas/CRUP, Generalitat Valenci

    Synthesis and evaluation of thiosemicarbazones functionalized with furyl moieties as new chemosensors for anion recognition

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    A family of heterocyclic thiosemicarbazone dyes (3a-f and 4) containing furyl groups were synthesized in good yields, characterized and their response in acetonitrile in the presence of selected anions was studied. Acetonitrile solutions of 3a-f and 4 show absorption bands in the 335-396 nm range which are modulated by the electron donor or acceptor strength of the heterocyclic systems appended to the thiosemicarbazone moiety. Fluoride, chloride, bromide, iodide, dihydrogen phosphate, hydrogen sulphate, nitrate, acetate and cyanide anions, were used in recognition studies. From these anions, only sensing features were seen for fluoride, cyanide, acetate and dihydrogen phosphate. Two clearly different chromo-fluorogenic behaviours were observed, (i) a small shift of the absorption band due to the coordination of the anions with the thiourea protons and (ii) the appearance of a new red shifted band due to deprotonation. For the latter effect, a change in the colour solution from pale yellow to purple was observed. Fluorescence studies were also in agreement with the different effects observed in the UV/Vis titrations. In this case, hydrogen bonding interactions were visible through the enhancement of the emission band, whereas deprotonation induced the appearance of a new red-shifted emission. Logarithms of stability constants for the two processes (complex formation + deprotonation) for receptors 3a-f in the presence of fluoride and acetate anions were determined from spectrophotometric titrations using the HypSpec V1.1.18 program. Semi-empirical calculations to evaluate the hydrogen-donating ability of the receptors and a prospective electrochemical characterization of compound 3b in the presence of fluoride were also performed.Fundação para a Ciência e a Tecnologia (FCT), Acções Integradas Luso-espanholas/CRUP, Generalitat Valenciana

    Sobre la presencia de Zenopsis conchifer (Lowe, 1852) (Osteichthyes, Zeidae) in el Mar Mediterráneo

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    5 pages, 2 figures, 2 tables[EN] On the occurrence of Zenopsis conchifer (Lowe, 1852) (Osteichthyes, Zeidae) in the Mediterranean Sea.- The capture of four specimens of Silvery John Dory (Zenopsis conchifer), a species recorded in the Mediterranean Sea for the first time in 2006, is reported from the Iberian coast (western Mediterranean). One of the specimens was caught near the Strait of Gibraltar and is probably a vagrant. Despite these catches, there is no evidence of a self- sustaining population, so this species should be considered as alien in the Mediterranean. © [2012] the authors licensee the journal[ES] Se informa de la captura de cuatro ejemplares de Zenopsis conchifer, especie cuya primera cita en el Mediterráneo data del año 2007, en las costas de la península Ibérica. Uno de los ejemplares fue capturado cerca del estrecho de Gibraltar, por lo que probablemente se trataría de un individuo errante. A pesar de estas capturas, no hay evidencia de la existencia de una población estable, por lo que la especie debe continuar siendo considerada como exótica en el MediterráneoPeer Reviewe

    Pharmacology of Ischemia–Reperfusion. Translational Research Considerations

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    Ischemia–reperfusion (IRI) is a complex physiopathological mechanism involving a large number of metabolic processes that can eventually lead to cell apoptosis and ultimately tissue necrosis. Treatment approaches intended to reduce or palliate the effects of IRI are varied, and are aimed basically at: inhibiting cell apoptosis and the complement system in the inflammatory process deriving from IRI, modulating calcium levels, maintaining mitochondrial membrane integrity, reducing the oxidative effects of IRI and levels of inflammatory cytokines, or minimizing the action of macrophages, neutrophils, and other cell types. This study involved an extensive, up-to-date review of the bibliography on the currently most widely used active products in the treatment and prevention of IRI, and their mechanisms of action, in an aim to obtain an overview of current and potential future treatments for this pathological process. The importance of IRI is clearly reflected by the large number of studies published year after year, and by the variety of pathophysiological processes involved in this major vascular problem. A quick study of the evolution of IRI-related publications in PubMed shows that in a single month in 2014, 263 articles were published, compared to 806 articles in the entire 1990.Medicin

    Allopurinol Protective Effect of Renal Ischemia by Downregulating TNF-α, IL-1β, and IL-6 Response

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    Allopurinol is a well-known antioxidant that protects tissue against ischemia and reperfusion injury, blocking purine catabolism, and possibly reducing TNF-α and other cytokines. It also plays a significant role in reducing the inflammatory processes by inhibiting chemotaxis and other inflammatory mediators. The objective of this study was to define the role of allopurinol regarding kidney ischemic injury particularly as to its effect on inflammatory molecules such as TNF-α, IL-1β, and IL-6 response. One hundred and twenty five rats were subjected to warm renal ischemia. Five more animals were included as sham. Animal survival and plasma levels of lipid peroxidation, myeloperoxidase, lactate dehydrogenase, glutathione, urea, creatinine, and cytokines were determined. Inflammatory parameters (TNF-α, IL-1β, and IL-6) were measured in all groups by quantitative immunosorbent assay. Further, immunohistological and histopathological studies were carried out on animals treated prior to, or following reperfusion with 10 and 50 mg/kg of Allopurinol. The statistical analysis included ANOVA and Fisher test as well as χ2 test. Significance was reached at a p < 0.05. The results of this study indicated that Allopurinol protected against kidney ischemia–reperfusion injury since significantly better results of survival, biochemical analysis, and histopathological testing were observed in treated animals as compared to ischemic controls. In conclusion, Allopurinol protected ischemic kidneys through a mechanism associated with downregulation of TNF-α, IL-1 β, and IL-6, in addition to other well-known effects such as decreased lipid peroxidation and neutrophil activity. It also increased antioxidant capacity and diminished endogenous peroxidase stain in renal ischemic tissue. Therefore, this experiment showed an effectiveness of allopurinol protection against proteomic and morphological damage

    Primeros datos sobre la situación del topillo de Cabrera Iberomys cabrerae (Thomas, 1906) en la provincia de Castelló y ampliación hacia el sur de su distribución en València

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    This is the first recorded finding in recent times of the Cabrera vole Iberomys cabrerae (Thomas, 1906) in Castelló province, where previously only fossil records have been identified in several Neolithic sites. In addition, it's known distribution is expanded to the south of the province of València. These discoveries, made in the Sierra del Toro (l'Alt Palància) and la Font de la Figuera (la Costera), are described and commented upon.Se registra por primera vez en la provincia de Castelló el topillo de Cabrera Iberomys cabrerae (Thomas, 1906) en tiempos recientes, donde tan solo se contaba con registro fósil en varios yacimientos datados en el Neolítico. Además se amplía hacia el sur su distribución conocida en València. Se describe y comenta su descubrimiento en la sierra del Toro (l'Alt Palància) y en la Font de la Figuera (la Costera)

    The Jak2 Pathway Is Activated In Idiopathic Pulmonary Fibrosis

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    Background: Idiopathic pulmonary fibrosis (IPF) is the most rapidly progressive and fatal fibrotic disorder, with no curative therapies. The signal transducer and activator of transcription 3 (STAT3) protein is activated in lung fibroblasts and alveolar type II cells (ATII), thereby contributing to lung fibrosis in IPF. Although activation of Janus kinase 2 (JAK2) has been implicated in proliferative disorders, its role in IPF is unknown. The aim of this study was to analyze JAK2 activation in IPF, and to determine whether JAK2/STAT3 inhibition is a potential therapeutic strategy for this disease. Methods and results: JAK2/p-JAK2 and STAT3/pSTAT3 expression was evaluated using quantitative real time-PCR, western blotting, and immunohistochemistry. Compared to human healthy lung tissue (n = 10) both proteins were upregulated in the lung tissue of IPF patients (n = 12). Stimulating primary ATII and lung fibroblasts with transforming growth factor beta 1 or interleukin (IL)-6/IL-13 activated JAK2 and STAT3, inducing epithelial to mesenchymal and fibroblast to myofibroblast transitions. Dual p-JAK2/p-STAT3 inhibition with JSI-124 or silencing of JAK2 and STAT3 genes suppressed ATII and the fibroblast to myofibroblast transition, with greater effects than the sum of those obtained using JAK2 or STAT3 inhibitors individually. Dual rather than single inhibition was also more effective for inhibiting fibroblast migration, preventing increases in fibroblast senescence and Bcl-2 expression, and ameliorating impaired autophagy. In rats administered JSI-124, a dual inhibitor of p-JAK2/p-STAT3, at a dose of 1 mg/kg/day, bleomycin-induced lung fibrosis was reduced and collagen deposition in the lung was inhibited, as were JAK2 and STAT3 activation and several markers of fibrosis, autophagy, senescence, and anti-apoptosis. Conclusions: JAK2 and STAT3 are activated in IPF, and their dual inhibition may be an attractive strategy for treating this disease
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