2,720 research outputs found

    Hepatitis C: crioglobulinemia y linfoma no-Hodgkin

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    La infección por el virus de la hepatitis C juega un papel principal en la patogénesis de la crioglobulinemia mixta, promoviendo la activación y expansión de las células B. Estos reajustes moleculares inducen la síntesis de crioglobulinas y la aparición de la vasculitis crioglobulinémica. El aclaramiento del virus provoca la resolución de las manifestaciones clínicas y de las alteraciones inmunológicas observados en la crioglobulinemia mixta en un alto porcentaje de los pacientes, pero no en todos. En algunos casos, la crioglobulinemia puede aparecer tras la respuesta virológica sostenida. Muchos mecanismos de la patogénesis de la crioglobulinemia mixta están fuertemente relacionados con la infección por VHC y, cuando el virus es eliminado, hay una mejoría en el curso de la enfermedad. Aun así, los pasos independientes relacionados con otros factores no mejoran tras la erradicación del virus. En algunos tipos de linfomas no-Hodgkin de bajo grado (linfoma linfoplasmocítico y linfoma de la zona marginal) la respuesta sostenida tras el aclaramiento viral induce una remisión de la neoplasia. El VHC tiene un papel secundario en los linfomas agresivos y el aclaramiento del virus puede no inducir la remisión, pero puede disminuir la hepatotoxicidad asociada a la quimioterapia. Por tanto, en la hepatitis C crónica, la combinación de interferón pegilado y ribavirina es altamente recomendable en el tratamiento de la crioglobulinemia mixta sintomática y los linfomas noHodgkin asociados al VHC.Hepatitis C. Crioglobulinemia. Linfoma noHodgkinHepatitis C virus infection plays a major role in the pathogenesis of mixed cryoglobulinemia, promoting activation and expansion of B cells. These molecular rearrangements induce synthesis of cryoglobulins and the appearance of cryoglobulinemic vasculitis. Clearance of the virus promotes resolution of the clinical manifestations and immunological disorders seen in mixed cryoglobulinemia in a large percentage of patients, but not in all. In some cases, cryoglobulinemia could appear after sustained response. Several steps in the pathogenesis of mixed cryoglobulinemia are strongly related to HCV infection and when the virus is eliminated, the disease course improves. However, independent steps related to other factors do not improve following viral clearance. In some types of low-grade non-Hodgkin lymphoma (lymphomoplasmocytic lymphoma, marginal zone lymphoma) sustained response following antiviral treatment induces remission of the neoplasm. HCV has a minor role in aggressive lymphomas and clearance of the virus may not induce remission, but could decrease the hepatotoxicity associated with the chemotherapy. Therefore, in chronic hepatitis C, the combination of peginterferon + ribavirin is strongly recommended in treating symptomatic mixed cryoglobulinemia and HCV-related non-Hodgkin lymphomas.Hepatitis C. Cryoglobulinemia. Non-Hodgkin lymphom

    Exploitation of Liquefied Natural Gas Cold Energy in Floating Storage Regasification Units

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    [Abstract] This paper aims to review regasification technology installed in Floating Storage Regasification Units (FSRUs) and the potential offered by the exploitation of cold energy from liquefied natural gas (LNG) in these vessels. The assessment describes the main characteristics of regasification systems along with their respective advantages and limitations. Regasification systems in direct exchange (seawater and steam) and systems with intermediate fluids that use propane or water-glycol in the heat transfer process are studied. In recent years, water-glycol systems have cornered the market. The mixture, besides reducing the risk of freezing, is non-flammable, economical and highly available. Thermodynamic analysis of the regasification process shows that LNG cold energy is the main source of residual energy in these vessels; the specific energy and exergy content is more than double that of engine exhaust gases. Exploitation of this cold energy in power cycles could significantly reduce FSRUs harmful emissions and electrical energy could even be exported to shore. The organic Rankine cycle technology is the most well-known and widely studied, although scientific literature is scarce and there is a need to propose new regasification systems with cold energy exploitation that can be adopted on these vessels

    COVID-19 and the liver: the chicken or the egg dilema

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    After the publication of our meta-analysis, in which we demonstrated that aspartate aminotransferase (AST), alanine aminotransferase (ALT) and total bilirubin were related to a poor prognosis in patients suffering COVID-19, some authors raised the question about whether these findings are directly linked, or they are epiphenomena

    Looking for a new name for non-alcoholic fatty liver disease in Spanish: esteatosis hepatica metabolica (EHmet)

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    El nombre de una enfermedad no sigue ningún protocolo definido y es habitual la aceptación por parte de la comunidad científica de diversas variantes en función de las costumbres de cada lugar. Hay ejemplos de entidades prevalentes con curiosos procesos de denominación, como la diabetes mellitus. La primera palabra, "diabetes", proviene del griego dia (a través), be (ir) y tes (factor), mientras que la segunda palabra, "mellitus", proviene del latín melli (miel). En consecuencia, diabetes mellitus significa literalmente "el factor dulce que atraviesa...", perteneciente a una diuresis excesiva y dulce. Por lo tanto, podríamos deducir que no se requiere una definición que represente exactamente la fisiopatología de la enfermedad en particular.The name of a disease does not follow any defined protocol and the scientific community's acceptance of several variants based on the customs of every location is usual. There are examples of prevalent entities with curious naming processes, such as diabetes mellitus. The first word, "diabetes", comes from the Greek dia (through), be (to go), and tes (factor), while the second word, "mellitus", comes from Latin melli (honey). As a consequence, diabetes mellitus literally means "the sweet factor that goes through…", pertaining to an excessive and sweet diuresis. Thus, we could deduce that a definition representing exactly the pathophysiology of the particular disease is not required

    Generation of H₂ on Board Lng Vessels for Consumption in the Propulsion System

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    [Abstract] At present, LNG vessels without reliquefaction plants consume the BOG (boil-off gas) in their engines and the excess is burned in the gas combustion unit without recovering any of its energy content. Excess BOG energy could be captured to produce H₂, a fuel with high energy density and zero emissions, through the installation of a reforming plant. Such H₂ production would, in turn, require on-board storage for its subsequent consumption in the propulsion plant when navigating in areas with stringent anti-pollution regulations, thus reducing CO₂ and SOₓ emissions. This paper presents a review of the different H₂ storage systems and the methods of burning it in propulsion engines, to demonstrate the energetic viability thereof on board LNG vessels. Following the analysis, it is identified that a pressurised and cooled H₂ storage system is the best suited to an LNG vessel due to its simplicity and the fact that it does not pose a safety hazard. There are a number of methods for consuming the H₂ generated in the DF engines that comprise the propulsión plant, but the use of a mixture of 70% CH₄-30% H₂ is the most suitable as it does not require any modifications to the injection system. Installation of an on-board reforming plant and H₂ storage system generates sufficient H₂ to allow for almost 3 days’ autonomy with a mixture of 70%CH₄-30%H₂. This reduces the engine consumption of CH₄ by 11.38%,thus demonstrating that the system is not only energy-efficient, but lends greater versatility to the vessel

    Wetting of Nematic Liquid Crystals on Crenellated Substrates: A Frank–Oseen Approach

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    We revisit the wetting of nematic liquid crystals in contact with crenellated substrates, studied previously using the Landau–de Gennes formalism. However, due to computational limitations, the characteristic length scales of the substrate relief considered in that study limited to less than 100 nematic correlation lengths. The current work uses an extended Frank–Oseen formalism, which includes not only the free-energy contribution due to the elastic deformations but also the surface tension contributions and, if disclinations or other orientational field singularities are present, their core contributions. Within this framework, which was successfully applied to the anchoring transitions of a nematic liquid crystal in contact with structured substrates, we extended the study to much larger length scales including the macroscopic scale. In particular, we analyzed the interfacial states and the transitions between them at the nematic–isotropic coexistence

    Reserva Natural Ramsar de El Rincón y laguna de Santiago (Moriles, Córdoba): génesis y funcionamiento desde una perspectiva geomorfológica

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    Se lleva a cabo un análisis de los factores geomorfológicos que condicionan la génesis y el funcionamiento de la actual Reserva Natural Ramsar de El Rincón, así como de la cercana laguna de Santiago (Moriles, Córdoba, Spain).An analysis about geomorfological factors conditions of genesis and current hidrological function of El Rincón Ramsar Natural Reserve and closed Santiago smalllake (Moriles, Córdoba, Spain) is carried out

    Laguna o Lago de Zóñar (Aguilar de la Frontera, Córdoba): consideraciones sobre su génesis reciente

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    Se lleva a cabo un análisis de los factores ecológicos que participan en la génesis, evolución y estado actual de la Reserva Natural de Zóriar (Aguilar de la Frontera, Córdoba).An analysis about ecological factors participant in the genesis, evolution and current situation of Zóriar Natural Reserve (Aguilar de la Frontera, Córdoba), is carried out

    Usefulness of bioelectrical impedance analysis for monitoring patients with refractory ascites

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    Background: bioelectrical impedance analysis is a technique for the determination of the hydropic component. The hydropic component, determined by blood volume, could be a reflection of the hemodynamic situation. This study aimed to evaluate the usefulness of peripheral bioelectrical impedance analysis (BIA) for the prediction of hemodynamic changes in large-volume paracentesis and prognosis. Methods: this was a proof-of-concept prospective study of 14 patients with liver cirrhosis and refractory ascites. Peripheral bioimpedance was measured three times using a portable device, IVOL®, before and after large-volume paracentesis, at different frequencies (5, 10, 20, 50, 100 and 200 kHz). Consequently, resistance, reactance and phase angle were obtained, both pre- and post-paracentesis (the difference between them was defined as Δ). Results: the mean age of patients was 62.2 ± 9.6 years, the Child-Pugh was 8.4 ± 1.3 and the MELD score was 15.2 ± 3.9. A direct correlation between the extraction of ascitic fluid and Δresistance (10 kHz [r = 0.722; n = 12; p = 0.008], 20 kHz [r = 0.658; n = 12; p = 0.020] and 50 kHz [r = 0.519; n = 14; p = 0.057]) was observed. The presence of edema was related to lower values of both pre-paracentesis resistance (10 Hz [23.9 ± 8 vs 32.2 ± 4; p = 0.043]) and phase angle (5 kHz [-1.9 ± 2.8 vs 5.9 ± 7.3; p = 0.032]). Pre-paracentesis phase angle was directly correlated with the decline in blood pressure after paracentesis at lower frequencies (5 kHz [r = 0.694; n = 13; p = 0.008] and 10 kHz [r = 0.661; n = 13; p = 0.014]). Lower frequencies of Δphase-angle impacted on patient prognosis (5 kHz [-8.6 ± 5 vs -2.5 ± 2.7; p = 0.021]), patients with Δphase-angle 5 kHz > -4 had a higher rate of mortality (83.3% [5/6] vs 0% [0/6]; logRank 7.306, p = 0.007). Δresistance values were associated with overt HE at six months (10 kHz [4.9 ± 2.5 vs -0.4 ± 4.7; p = 0.046]). Conclusions: in conclusion, a significant correlation between peripheral impedance and hemodynamic changes was found. Impedance was also significantly related to prognosis and overt hepatic encephalopathy
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