246 research outputs found

    Determinación del flujo de calor a partir de sondeos petroleros en la Cuenca Catalano-Balear

    Get PDF
    A method using information from oil wells has been applied to calculate heat flow at seven oil wells in the Valencia trough, a Neogene extensional basin located in the western Mediterranean. Most of these weils penetrate the Cenozoic sedimentary cover and the underlying Mesozoic sequences and the Paleozoic basement. The basic data set consists of well logs, rock samples including cuttings and cores, and bottom hole (BHT) and dril1 stem test (DST) temperature data. Thermal conductivity of the rock matrix is determined from the conductivities and volumetric fractions of its mineral components by using a geometrical mean model. The in-situ thermal conductivity profile is then obtained as a function of porosity, and it is corrected for in-situ temperature conditions. The sonic log has been used to estimate the porosity profile, which has been corrected depending on the clay content of the formation. Finally, vertical heat flow variation is calculated at every well by combining bulk thermal conductivity profile and geothermal gradients.The bulk thermal conductivity has been shown to be very sensitive to lithologic and porosity changes, with values that vary from 1.5 W m-K-' for shales with over 40 percent porosity, to about 4.3 W m-' K-' for dolomites and consolidated quartz-rich sandstones that constitute the basement. The maximum thermal conductivity values are attained for the basement materials and are due to the low porosity (caused by compaction and burial) and to the high matrix conductivities of Mesozoic carbonates and sandstones. The mean bulk thermal conductivity of the sediments is found to be about 2 W m-' K-l. Therefore, a thermal blanketing effect is likely to occur due to the conductivity contrast between the sedimentary cover and the underlying basement. This effect, which has been neglected in previous models of the thermal evolution of the Valencia trough, probably has acted to slow down post-extensional lithospheric cooling and to reduce tectonic subsidence.A regional thermal gradient of 3612 "C km-' is obtained from the available temperature data. This value is siightly lower than that estimated from a set of wells in the southwestern part of the basin. The calculated heat flow values are highly scattered, the maximum value being located in the southwestern part of the basin. As a consequence, the resulting heat flow agrees with the increase towards the SW previously observed in the Valencia trough. The mean heat flow value in the study area is determined to be 85-90 mW m-2. Although thermal conductivity could be overestimated, this value is too high to be just a consequence of the rifting process in the Valencia trough, since most of the wells considered are located in the northernmost part of the basin. The thermal effect of groundwater circulation is proposed to be in part responsible for the positive and negative thermal gradient anomalies.Fracturing and karstification, which has been widely recognized in the Mesozoic carbonates in the basement, together with the temperature data and porosity results, support this hypothesis

    Neotectónica e períodos de recorrência de grandes sismos e tsunamis na margem SW Ibérica e Golfo de Cádis

    Get PDF
    Neste trabalho usámos o método numérico das placas finas (Bird, 1999) para modelar a Neotectónica no Golfo de Cadiz e estimar os períodos de recorrência de grandes sismos e tsunamis. Foram testadas várias configurações de falhas e condições fronteira, e os resultados comparados com as observações de GPS, tensão e deformação sísmica. O melhor ajuste às observações é obtido com um modelo que apresenta uma taxa de movimentação de 1 mm/a nos cavalgamentos com orientação E-O e NE-SO, o que corresponde a períodos de recorrência de 1150, 3620 e 9900 anos para sismos de magnitude Mw de 7, 8 e 8.75

    Aging-associated symptoms in the physician-patient dialogue in a group of long-term diagnosed HIV-infected individuals

    Get PDF
    Background: The significant decrease in mortality has resulted in a large number of individuals aged over 50 living with HIV infection. Additionally, the coexistence of certain pathologies suggests premature aging. In this scenario, the presence of aging-associated symptoms in the physician-patient dialogue is yet to be explored. Methods: Cross-sectional observational study to evaluate the presence of aging-associated symptoms in the physician-patient dialogue and to explore the possible differences between genders in a sample of 100 HIV-1 infected subjects diagnosed at least 15 years ago. The survey assessed questions/comments made by the patient, questions/comments made by the physician and patients’ interest in obtaining more information than was provided. Number of patients and percentages were given and compared using the w2 or Fisher exact test (as appropriate). Results: Participants were 60 men and 40 women, diagnosed with HIV infection a median (IQ) of 18 (15.7–21) years ago, who had a nadir CD4 and CD4 cell count at the study entry of 172 (95–272) and 543 (403–677), respectively. Eighty percent of the subjects had VL <25 copies and 42% were HCV/HIV co-infected (31 subjects with low fibrosis stage). The infection route had been mainly intravenous drug use (37%) and MSM (32%). Men and women had similar demographic and clinical characteristics. Sixty-two percent of the participants acknowledged asking their physicians about aging-associated symptoms (58% men vs 66% women; p=0.50), 48% reported that their physicians had provided information without having been asked (48% men vs 55% women; p=0.51) and 75% confirmed that they would like to have more information about aging-associated symptoms (22% men vs 80% women; p<0.001). Conclusions: Around half of the men and women interviewed had discussed aging-associated symptoms with their physician. However, this seemed insufficient for four-fifths of the women, who would have liked to have obtained more information about aging

    The disruption of JEN1 from Candida albicans impairs the transport of lactate

    Get PDF
    A lactate permease was biochemically identified in Candida albicans RM1000 presenting the following kinetic parameters at pH 5.0: Km 0.33 ± 0.09 mM and Vmax 0.85± 0.06 nmol s-1 mg dry wt-1. Lactate uptake was competitively inhibited by pyruvic and propionic acids; acetic acid behaved as a non-competitive substrate. An ORF homologous to Saccharomyces cerevisiae gene JEN1 was identified (CaJEN1). Deletions of both CaJEN1 alleles of C. albicans (resulting strain CPK2) resulted in the loss of all measurable lactate permease activity. No CaJEN1 mRNA was detectable in glucose-grown cells neither activity for the lactate transporter. In a medium containing lactic acid, CaJEN1 mRNA was detected in the RM1000 strain, and no expression was found in cells of CPK2 strain. In a strain deleted in the CaCAT8 genes the expression of CaJEN1 was significantly reduced, suggesting the role of this gene as an activator for CaJEN1 expression. Both in C. albicans and in S. cerevisiae cells CaJEN1-GFP fusion was expressed and targeted to the plasma membrane. The native CaJEN1 was not functional in a S. cerevisiae jen1Δ strain. Changing ser217-CTG codon (encoding leucine in S. cerevisiae) to a TCC codon restored the permease activity in S. cerevisiae, proving that the CaJEN1 gene codes for a monocarboxylate transporter.Deutsche Forschungsgemeinschaft (SFB 579).Fundação para a Ciência e a Tecnologia (FCT) - Programa Operacional “Ciência, Tecnologia, Inovação” (POCTI) - POCTI/1999/BME/36625 (Eixo 2, Medida 2.3, QCAIII-FEDER) , SFRH/BD/4699/2001 , PRAXIS XXI/BD/18198/98

    Differential body composition effects of protease inhibitors recommended for initial treatment of HIV infection: A randomized clinical trial

    Full text link
    This article has been accepted for publication in Clinical Infectious Diseases ©2014 The Authors .Published by Oxford University Press on Clinical Infectious Disease 60.5. DOI: 10.1093/cid/ciu898Background. It is unclear whether metabolic or body composition effects may differ between protease inhibitor-based regimens recommended for initial treatment of HIV infection. Methods. ATADAR is a phase IV, open-label, multicenter randomized clinical trial. Stable antiretroviral-naive HIV-infected adults were randomly assigned to atazanavir/ritonavir 300/100 mg or darunavir/ritonavir 800/100 mg in combination with tenofovir/emtricitabine daily. Pre-defined end-points were treatment or virological failure, drug discontinuation due to adverse effects, and laboratory and body composition changes at 96 weeks. Results. At 96 weeks, 56 (62%) atazanavir/ritonavir and 62 (71%) darunavir/ritonavir patients remained free of treatment failure (estimated difference 8.2%; 95%CI -0.6 to 21.6); and 71 (79%) atazanavir/ritonavir and 75 (85%) darunavir/ritonavir patients remained free of virological failure (estimated difference 6.3%; 95%CI -0.5 to 17.6). Seven vs. five patients discontinued atazanavir/ritonavir or darunavir/ritonavir due to adverse effects. Total and HDL cholesterol similarly increased in both arms, but triglycerides increased more in atazanavir/ritonavir arm. At 96 weeks, body fat (estimated difference 2862.2 gr; 95%CI 726.7 to 4997.7; P=0.0090), limb fat (estimated difference 1403.3 gr; 95%CI 388.4 to 2418.2; P=0.0071), and subcutaneous abdominal adipose tissue (estimated difference 28.4 cm2; 95%CI 1.9 to 55.0; P=0.0362) increased more in atazanavir/ritonavir than in darunavir/ritonavir arm. Body fat changes in atazanavir/ritonavir arm were associated with higher insulin resistance. Conclusions. We found no major differences between atazanavir/ritonavir and darunavir/ritonavir in efficacy, clinically-relevant side effects, or plasma cholesterol fractions. However, atazanavir/ritonavir led to higher triglycerides and total and subcutaneous fat than darunavir/ritonavir and fat gains with atazanavir/ritonavir were associated with insulin resistanceThis is an Investigator Sponsored Research study. It was supported in part by research grants from Bristol‐Myers Squibb and Janssen‐Cilag; Instituto de Salud Carlos III (PI12/01217) and Red Temática Cooperativa de Investigación en SIDA G03/173 (RIS‐EST11), Ministerio de Ciencia e Innovación, Spain. (Registration number: NCT01274780; registry name: ATADAR; EUDRACT; 2010‐021002‐38)

    Chikungunya virus infections among travellers returning to Spain, 2008 to 2014

    Get PDF
    Since the first documented autochthonous transmission of chikungunya virus in the Caribbean island of Saint Martin in 2013, the infection has been reported within the Caribbean region as well as North, Central and South America. The risk of autochthonous transmission of chikungunya virus becoming established in Spain may be elevated due to the large numbers of travellers returning to Spain from countries affected by the 2013 epidemic in the Caribbean and South America, as well as the existence of the Aedes albopictus vector in certain parts of Spain. We retrospectively analysed the laboratory diagnostic database of the National Centre for Microbiology, Institute of Health Carlos III (CNM-ISCIII) from 2008 to 2014. During the study period, 264 confirmed cases, of 1,371 suspected cases, were diagnosed at the CNM-ISCIII. In 2014 alone, there were 234 confirmed cases. The highest number of confirmed cases were reported from the Dominican Republic (n = 136), Venezuela (n = 30) and Haiti (n = 11). Six cases were viraemic in areas of Spain where the vector is present. This report highlights the need for integrated active case and vector surveillance in Spain and other parts of Europe where chikungunya virus may be introduced by returning travellers

    Statins Disrupt CCR5 and RANTES Expression Levels in CD4(+) T Lymphocytes In Vitro and Preferentially Decrease Infection of R5 Versus X4 HIV-1

    Get PDF
    BACKGROUND: Statins have previously been shown to reduce the in vitro infection of human immunodeficiency virus type 1 (HIV-1) through modulation of Rho GTPase activity and lipid raft formation at the cell surface, as well as by disrupting LFA-1 incorporation into viral particles. PRINCIPLE FINDINGS: Here we demonstrate that treatment of an enriched CD4(+) lymphocyte population with lovastatin (Lov), mevastatin (Mev) and simvastatin (activated and non-activated, Sim(A) and Sim(N), respectively) can reduce the cell surface expression of the CC-chemokine receptor CCR5 (P<0.01 for Sim(A) and Lov). The lowered CCR5 expression was associated with down-regulation of CCR5 mRNA expression. The CC-chemokine RANTES protein and mRNA expression levels were slightly increased in CD4(+) enriched lymphocytes treated with statins. Both R5 and X4 HIV-1 were reduced for their infection of statin-treated cells; however, in cultures where statins were removed and where a decrease in CCR5 expression was observed, there was a preferential inhibition of infection with an R5 versus X4 virus. CONCLUSIONS: The results indicate that the modulation of CC-chemokine receptor (CCR5) and CC-chemokine (RANTES) expression levels should be considered as contributing to the anti-viral effects of statins, preferentially inhibiting R5 viruses. This observation, in combination with the immunomodulatory activity exerted by statins, suggests they may possess more potent anti-HIV-1 activity when applied during the early stages of infection or in lowering viral transmission. Alternatively, statin treatment could be considered as a way to modulate immune induction such as during vaccination protocols

    European survey on laboratory preparedness, response and diagnostic capacity for crimean-congo haemorrhagic fever, 2012

    Get PDF
    Crimean-Congo haemorrhagic fever (CCHF) is an infectious viral disease that has (re-)emerged in the last decade in south-eastern Europe, and there is a risk for further geographical expansion to western Europe. Here we report the results of a survey covering 28 countries, conducted in 2012 among the member laboratories of the European Network for Diagnostics of 'Imported' Viral Diseases (ENIVD) to assess laboratory preparedness and response capacities for CCHF. The answers of 31 laboratories of the European region regarding CCHF case definition, training necessity, biosafety, quality assurance and diagnostic tests are presented. In addition, we identifi
    corecore