36 research outputs found

    Textural and mineral-chemistry constraints on columbite group minerals in the Penouta deposit: evidence from magmatic and fluid-related processes.

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    The Penouta Sn-Ta deposit, in the northwest of Spain, is a greisenized granitic cupola where Ta minerals occur mainly as disseminations in a leucogranite body intruded in Precambrian-Lower Cambrian gneises and mica-schists. This leucogranite is a medium- to fine-grained inequigranular rock consisting mainly of quartz, albite, K-feldspar and muscovite. Accessory minerals are mainly of spessartine, zircon, cassiterite, Nb-Ta oxides, monazite, xenotime, native bismuth and pyrite. The alteration processes were mainly albitization, muscovitization and kaolinitization. This leucogranite is peraluminous and P-poor, with 0.03-0.07 wt.% P2O5, 900-1500 ppm Rb, 30-65 ppm Cs, 120-533 ppm Li, 80-140 ppm Ta, 51-81 ppm Nb and up to 569 ppm of Sn. Mineralogical characterization of Nb-Ta oxide minerals was determined by X-ray diffraction, scanning electron microscopy, electron microprobe analysis and mineral liberation analysis. Mn-rich members of the columbite-group minerals (CGM) are the most common Ta-bearing phases, but microlite, wodginite, tapiolite and Ta-rich cassiterite occur also. CGM crystals are commonly zoned concentrically, with a Nb-rich core surrounded by a Ta-rich rim, with a sharp boundary between them. Convoluted zoning occurs also. Dissolution textures resulting from the corrosion of columbite and tantalite rims, in particular, are common. TheMn/(Mn + Fe) ratio varies between 0.33 and 0.97 and the Ta/(Ta + Nb) ratio between 0.07 and 0.93. Wodginite and microlite formed as late replacements of CGM and occur associated with tantalite and cassiterite. Subhedral to anhedral cassiterite crystals, usually up to 200 μmacross, occur in two generations: the earlier one is Nb,Ta-poor whereas in the later generation, the Ta content can reach >9 wt.%of Ta2O5 and 1.7 wt.%of Nb. The presence of a fluid phase in the apical zone of the granite, probably related to the separation of a fluid/vapour of the melt, could explain the sponge-like textures, the Ta enrichment associated with these textures, the occurrence of Taenriched mineral phases (microlite and wodginite) and their common interstitial character

    Pretransplant CMV-Specific T-Cell Immunity But Not Dose of Antithymocyte Globulin Is Associated With Recovery of Specific Immunity After Kidney Transplantation

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    Background: This is a prospective, multicenter, observational study in cytomegalovirus (CMV)-seropositive kidney transplant recipients with pretransplant CMV-specific cell-mediated immunity (CMV-CMI) receiving antithymocyte globulin (ATG). We aimed to investigate posttransplant CMV-CMI over time and the impact of the dose-dependent ATG. Methods: CMV-CMI was assessed at days +30, +45, +60, and +90 after transplantation with the QuantiFERON-CMV assay. A reactive result (interferon-? [IFN-?] ? 0.2 IU/mL) indicated a positive CMV-CMI. Results: A total of 78 positive CMV-CMI patients were enrolled in the study, of which 59.5% had a positive CMV-CMI at day +30 and 82.7% at day +90. Multivariate logistic regression analysis showed that ATG dose was not associated with positive CMV-CMI at any point. However, pretransplant IFN-? level (>12 IU/mL vs ?12 IU/mL) was associated with positive CMV-CMI at day +30 (odds ratio, 12.9; 95% confidence interval, 3.1-53.3; P < .001). In addition, all the patients who did not recover CMV-CMI at day +90 had a pretransplant IFN-? level ?12 IU/mL. Conclusions: More than half of CMV-seropositive kidney transplant recipients receiving ATG recover (or maintain) CMV-CMI by the first month after transplantation. The pretransplant IFN-? level, but not the ATG dose, shows a strong association with the kinetics of this recovery.This work was supported by the Fundación Progreso y Salud, Consejería de Salud y Familias, Junta de Andalucía (grant number PI-0294-2014); Spanish Ministry of Science and Innovation, Instituto de Salud Carlos III (grant number CP 18/00073 to M. F. R.); Plan Nacional de I+D+i 2013–2016 and Instituto de Salud Carlos III, Subdirección General de Redes y Centros de Investigación Cooperativa, Ministerio de Ciencia e Innovación, Spanish Network for Research in Infectious Diseases (grant numbers REIPI RD16/0016/0002, RD16/0016/0003, RD16/0016/0007, RD16/0016/0008, RD16/0016/0009 and RD16/0016/0012); cofinanced by European Development Regional Fund “A way to achieve Europe,” Operative Program Intelligent Growth 2014- 2020; Spanish Network for Research in Renal Diseases (grant numbers RD16/0009/0006, RD16/0009/0008, RD16/0009/0013, RD16/0009/0014, RD16/0009/0019, RD16/0009/0034); Centro de Investigación Biomédica en Red Enfermedades Respiratorias (grant number CB06/06/0058); and Spanish Group for the Study of Infection in Transplantation and the Immunocompromised Host of the Spanish Society of Infectious Diseases and Clinical Microbiolog

    Oral fosfomycin for the treatment of lower urinary tract infections among kidney transplant recipients—Results of a Spanish multicenter cohort

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    Preliminary results of this study were presented at the 29th European Congress of Clinical Microbiology and Infectious Diseases (ECCMID), held in Amsterdam, The Netherlands, from 13 to 16 April, 2019 (oral communication O‐0699).Oral fosfomycin may constitute an alternative for the treatment of lower urinary tract infections (UTIs) in kidney transplant recipients (KTRs), particularly in view of recent safety concerns with fluroquinolones. Specific data on the efficacy and safety of fosfomycin in KTR are scarce. We performed a retrospective study in 14 Spanish hospitals including KTRs treated with oral fosfomycin (calcium and trometamol salts) for posttransplant cystitis between January 2005 and December 2017. A total of 133 KTRs developed 143 episodes of cystitis. Most episodes (131 [91.6%]) were produced by gram‐negative bacilli (GNB), and 78 (54.5%) were categorized as multidrug resistant (including extended‐spectrum β‐lactamase‐producing Enterobacteriaceae [14%] or carbapenem‐resistant GNB [3.5%]). A median daily dose of 1.5 g of fosfomycin (interquartile range [IQR]: 1.5‐2) was administered for a median of 7 days (IQR: 3‐10). Clinical cure (remission of UTI‐attributable symptoms at the end of therapy) was achieved in 83.9% (120/143) episodes. Among those episodes with follow‐up urine culture, microbiological cure at month 1 was achieved in 70.2% (59/84) episodes. Percutaneous nephrostomy was associated with a lower probability of clinical cure (adjusted odds ratio: 10.50; 95% confidence interval: 0.98‐112.29; P = 0.052). In conclusion, fosfomycin is an effective orally available alternative for treating cystitis among KTRs.This study was supported by Plan Nacional de I+D+i 2013‐2016 and Instituto de Salud Carlos III, Subdirección General de Redes y Centros de Investigación Cooperativa, Ministerio de Ciencia, Innovación y Universidades, Spanish Network for Research in Infectious Diseases (REIPI RD16/0016)—cofinanced by the European Development Regional Fund “A way to achieve Europe”; the Group for Study of Infection in Transplantation and the Immunocompromised Host (GESITRA‐IC) of the Spanish Society of Clinical Microbiology and Infectious Diseases (SEIMC); and the Spanish Network for Research in Renal Diseases (REDInREN RD16/0009). MFR holds a research contract “Miguel Servet” (CP 18/00073) from the Spanish Ministry of Science, Innovation and Universities, Instituto de Salud Carlos III

    Use of tocilizumab in kidney transplant recipients with COVID-1

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    Acute respiratory distress syndrome associated with coronavirus infection is related to a cytokine storm with large interleukin-6 (IL-6) release. The IL-6-receptor blocker tocilizumab may control the aberrant host immune response in patients with coronavirus disease 2019 (COVID-19) . In this pandemic, kidney transplant (KT) recipients are a high-risk population for severe infection and showed poor outcomes. We present a multicenter cohort study of 80 KT patients with severe COVID-19 treated with tocilizumab during hospital admission. High mortality rate was identified (32.5%), related with older age (hazard ratio [HR] 3.12 for those older than 60 years, P = .039). IL-6 and other inflammatory markers, including lactic acid dehydrogenase, ferritin, and D-dimer increased early after tocilizumab administration and their values were higher in nonsurvivors. Instead, C-reactive protein (CRP) levels decreased after tocilizumab, and this decrease positively correlated with survival (mean 12.3 mg/L in survivors vs. 33 mg/L in nonsurvivors). Each mg/L of CRP soon after tocilizumab increased the risk of death by 1% (HR 1.01 [confidence interval 1.004-1.024], P = .003). Although patients who died presented with worse respiratory situation at admission, this was not significantly different at tocilizumab administration and did not have an impact on outcome in the multivariate analysis. Tocilizumab may be effective in controlling cytokine storm in COVID-19 but randomized trials are needed

    Manejo de la inmunosupresión en pacientes trasplantados de riñón con COVID19. Estudio multicéntrico nacional derivado del registro COVID de la Sociedad Española de Nefrología

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    Introduction: SARS CoV2 infection has had a major impact on renal transplant patients with a high mortality in the first months of the pandemic. Intentional reduction of immunosuppressive therapy has been postulated as one of the cornerstone in the management of the infection in the absence of targeted antiviral treatment. This has been modified according to the patient`s clinical situation and its effect on renal function or anti-HLA antibodies in the medium term has not been evaluated.Objectives: Evaluate the management of immunosuppressive therapy made during SARS-CoV2 infection, as well as renal function and anti-HLA antibodies in kidney transplant patients 6 months after COVID19 diagnosis.Material and methods: Retrospective, national multicentre, retrospective study (30 centres) of kidney transplant recipients with COVID19 from 01/02/20 to 31/12/20. Clinical variables were collected from medical records and included in an anonymised database. SPSS statistical software was used for data analysis.Results: renal transplant recipients with COVID19 were included (62.6% male), with a mean age of 57.5 years. The predominant immunosuppressive treatment prior to COVID19 was triple therapy with prednisone, tacrolimus and mycophenolic acid (54.6%) followed by m-TOR inhibitor regimens (18.6%). After diagnosis of infection, mycophenolic acid was discontinued in 73.8% of patients, m-TOR inhibitor in 41.4%, tacrolimus in 10.5% and cyclosporin A in 10%. In turn, 26.9% received dexamethasone and 50.9% were started on or had their baseline prednisone dose increased. Mean creatinine before diagnosis of COVID19, at diagnosis and at 6 months was: 1.7 +/- 0.8, 2.1 +/- 1.2 and 1.8 +/- 1 mg/dl respectively (p < 0.001). 56.9% of the patients (N = 350) were monitored for anti-HLA antibodies. 94% (N = 329) had no anti-HLA changes, while 6% (N = 21) had positive anti-HLA antibodies. Among the patients with donor-specific antibodies post-COVID19 (N = 9), 7 patients (3.1%) had one immunosuppressant discontinued (5 patients had mycophenolic acid and 2 had tacrolimus), 1 patient had both immunosuppressants discontinued (3.4%) and 1 patient had no change in immunosuppression (1.1%), these differences were not significant.Conclusions: The management of immunosuppressive therapy after diagnosis of COVID19 was primarily based on discontinuation of mycophenolic acid with very discrete reductions or discontinuations of calcineurin inhibitors. This immunosuppression management did not influence renal function or changes in anti-HLA antibodies 6 months after diagnosis

    Efficacy and Safety of Oral Fosfomycin for Asymptomatic Bacteriuria in Kidney Transplant Recipients: Results from a Spanish Multicenter Cohort

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    Current guidelines recommend against systematic screening for or treating asymptomatic bacteriuria (AB) among kidney transplant (KT) recipients, although the evidence regarding episodes occurring early after transplantation or in the presence of anatomical abnormalities is inconclusive. Oral fosfomycin may constitute a good option for the treatment of posttransplant AB, particularly due to the emergence of multidrug-resistant (MDR) uropathogens. Available clinical evidence supporting its use in this specific setting, however, remains scarce. We performed a retrospective study in 14 Spanish institutions from January 2005 to December 2017. Overall, 137 episodes of AB diagnosed in 133 KT recipients treated with oral fosfomycin (calcium and trometamol salts) with a test-of-cure urine culture within the first 30 days were included. Median time from transplantation to diagnosis was 3.1 months (interquartile range [IQR], 1.1 to 10.5). Most episodes (96.4% [132/137]) were caused by Gram-negative bacteria (GNB), and 56.9% (78/137) were categorized as MDR (extended‐spectrum β‐lactamase‐producing Enterobacterales [20.4%] and carbapenem‐resistant GNB [2.9%]). Rate of microbiological failure at month 1 was 40.1% (95% confidence interval [CI], 31.9% to 48.9%) for the whole cohort and 42.3% (95% CI, 31.2% to 54.0%) for episodes due to MDR pathogens. Previous urinary tract infection (odds ratio [OR], 2.42; 95% CI, 1.11 to 5.29; P value = 0.027) and use of fosfomycin as salvage therapy (OR, 8.31; 95% CI, 1.67 to 41.35; P value = 0.010) were predictors of microbiological failure. No severe treatment-related adverse events were detected. Oral fosfomycin appears to be a suitable and safe alternative for the treatment (if indicated) of AB after KT, including those episodes due to MDR uropathogens.This study was supported by Plan Nacional de I+D+i 2013‐2016 and Instituto de Salud Carlos III (ISCIII), Subdirección General de Redes y Centros de Investigación Cooperativa, Ministry of Science and Innovation, Spanish Network for Research in Infectious Diseases (REIPI RD16/0016), and Spanish Network for Research in Renal Diseases (REDInREN RD16/0009) and cofinanced by the European Development Regional Fund entitled A way to achieve Europe. M.F.-R. holds a research contract (Miguel Servet, CP18/00073), from the Spanish Ministry of Science and Innovation, ISCIII.Peer reviewe

    Enfermedades crónicas

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    Adherencia al tratamiento farmacol&oacute;gico y relaci&oacute;n con el control metab&oacute;lico en pacientes con DM2Aluminio en pacientes con terapia de reemplazo renal cr&oacute;nico con hemodi&aacute;lisis en Bogot&aacute;, ColombiaAmputaci&oacute;n de extremidades inferiores: &iquest;est&aacute;n aumentando las tasas?Consumo de edulcorantes artificiales en j&oacute;venes universitariosC&oacute;mo crecen ni&ntilde;os normales de 2 a&ntilde;os que son sobrepeso a los 7 a&ntilde;osDiagn&oacute;stico con enfoque territorial de salud cardiovascular en la Regi&oacute;n MetropolitanaEfecto a corto plazo de una intervenci&oacute;n con ejercicio f&iacute;sico, en ni&ntilde;os con sobrepesoEfectos de la cirug&iacute;a bari&aacute;trica en pacientes con s&iacute;ndrome metab&oacute;lico e IMC &lt; 35 KG/M2Encuesta mundial de tabaquismo en estudiantes de profesiones de saludEnfermedades cr&oacute;nicas no transmisibles: Consecuencias sociales-sanitarias de comunidades rurales en ChileEpidemiolog&iacute;a de las muertes hospitalarias por patolog&iacute;as relacionadas a muerte encef&aacute;lica, Chile 2003-2007Estado nutricional y conductas alimentarias en adolescentes de 4&ordm; medio de la Regi&oacute;n de CoquimboEstudio de calidad de vida en una muestra del plan piloto para hepatitis CEvaluaci&oacute;n del proceso asistencial y de resultados de salud del GES de diabetes mellitus 2Factores de riesgo cardiovascular en poblaci&oacute;n universitaria de la Facsal, universidad de Tarapac&aacute;Implicancias psicosociales en la g&eacute;nesis, evoluci&oacute;n y tratamiento de pacientes con hipertensi&oacute;n arterial esencialInfarto agudo al miocardio (IAM): Realidad en el Hospital de Puerto Natales, 2009-2010Introducci&oacute;n de nuevas TIC y mejor&iacute;a de la asistencia a un programa de saludNi&ntilde;os obesos atendidos en el Cesfam de Puerto Natales y su entorno familiarPerfil de la mortalidad por c&aacute;ncer de cuello uterino en R&iacute;o de JaneiroPerfil del paciente primo-consultante del Programa de Salud Cardiovascular, Consultorio Cordillera Andina, Los AndesPrevalencia de automedicaci&oacute;n en mujeres beneficiarias del Hospital Comunitario de Til-TiPrevalencia de caries en poblaci&oacute;n preescolar y su relaci&oacute;n con malnutrici&oacute;n por excesoPrevalencia de retinopat&iacute;a diab&eacute;tica en comunas dependientes del Servicio de Salud Metropolitano Occidente (SSMOC)Problemas de adherencia farmacol&oacute;gica antihipertensiva en poblaci&oacute;n mapuche: Un estudio cualitativoRol biol&oacute;gico de los antioxidantes innatos en pacientes portadores de VIH/SidaSobrepeso en empleados de un restaurante de una universidad p&uacute;blica del estado de S&atilde;o Paul

    Management of immunosuppressive therapy in kidney transplant recipients with COVID-19. A multicentre national study derived from the Spanish Society of Nephrology COVID registry

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    Article disponible en castellà: http://hdl.handle.net/10230/55005Introduction: SARS CoV2 infection has had a major impact on renal transplant patients with a high mortality in the first months of the pandemic. Intentional reduction of immunosuppressive therapy has been postulated as one of the cornerstone in the management of the infection in the absence of targeted antiviral treatment. This has been modified according to the patient`s clinical situation and its effect on renal function or anti-HLA antibodies in the medium term has not been evaluated. Objectives: Evaluate the management of immunosuppressive therapy made during SARS-CoV2 infection, as well as renal function and anti-HLA antibodies in kidney transplant patients 6 months after COVID19 diagnosis. Material and methods: Retrospective, national multicentre, retrospective study (30 centres) of kidney transplant recipients with COVID19 from 01/02/20 to 31/12/20. Clinical variables were collected from medical records and included in an anonymised database. SPSS statistical software was used for data analysis. Results: renal transplant recipients with COVID19 were included (62.6% male), with a mean age of 57.5 years. The predominant immunosuppressive treatment prior to COVID19 was triple therapy with prednisone, tacrolimus and mycophenolic acid (54.6%) followed by m-TOR inhibitor regimens (18.6%). After diagnosis of infection, mycophenolic acid was discontinued in 73.8% of patients, m-TOR inhibitor in 41.4%, tacrolimus in 10.5% and cyclosporin A in 10%. In turn, 26.9% received dexamethasone and 50.9% were started on or had their baseline prednisone dose increased. Mean creatinine before diagnosis of COVID19, at diagnosis and at 6 months was: 1.7 ± 0.8, 2.1 ± 1.2 and 1.8 ± 1 mg/dl respectively (p < 0.001). 56.9% of the patients (N = 350) were monitored for anti-HLA antibodies. 94% (N = 329) had no anti-HLA changes, while 6% (N = 21) had positive anti-HLA antibodies. Among the patients with donor-specific antibodies post-COVID19 (N = 9), 7 patients (3.1%) had one immunosuppressant discontinued (5 patients had mycophenolic acid and 2 had tacrolimus), 1 patient had both immunosuppressants discontinued (3.4%) and 1 patient had no change in immunosuppression (1.1%), these differences were not significant. Conclusions: The management of immunosuppressive therapy after diagnosis of COVID19 was primarily based on discontinuation of mycophenolic acid with very discrete reductions or discontinuations of calcineurin inhibitors. This immunosuppression management did not influence renal function or changes in anti-HLA antibodies 6 months after diagnosis

    Manejo de la inmunosupresión en pacientes trasplantados de riñón con COVID19: estudio multicéntrico nacional derivado del registro COVID de la Sociedad Española de Nefrología

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    Data de publicació electrónica: 30-04-2022Introducción: la infección por SARS-CoV2 ha impactado de forma importante en los pacientes con trasplante renal causando una elevada mortalidad en los primeros meses de la pandemia. La reducción intencionada de la inmunosupresión se ha postulado como uno de los pilares en el manejo de la infección ante la falta de un tratamiento antiviral dirigido. Esta se ha modificado de acuerdo con la situación clínica de los pacientes, y su efecto sobre la función renal o los anticuerpos anti-HLA a medio plazo no ha sido evaluado. Objetivos: evaluar los cambios de inmunosupresión realizados durante la infección por SARS-CoV2, así como la función renal y los anticuerpos anti-HLA de los pacientes trasplantados de riñón a los 6 meses del diagnóstico de COVID19. Material y métodos: estudio retrospectivo, multicéntrico nacional (30 centros) de pacientes trasplantados de riñón con COVID19 desde el 01/02/20 al 31/12/20. Se recogieron las variables de la historia clínica y se incluyeron en una base de datos anonimizada. Se utilizó el programa estadístico SPSS para el análisis de resultados. Resultados: se incluyeron 615 trasplantados renales con COVID19 (62,6% varones), con una edad media de 57,5 años. El tratamiento inmunosupresor predominante antes del COVID19 era la triple terapia con prednisona, tacrolimus y ácido micofenólico (54,6%) seguido de los regímenes con inhibidores m-TOR (18,6%). Tras el diagnóstico de la infección se suspendió el ácido micofenólico en el 73,8% de los pacientes, el inhibidor m-TOR en el 41,4%, tacrolimus en el 10,5% y ciclosporina A en el 10%. A su vez, el 26,9% recibieron dexametasona y al 50,9% se les inició o aumentó la dosis de prednisona basal. la creatinina media antes del diagnóstico de COVID19, en el momento del diagnóstico y a los 6 meses fue de 1,7 ± 0,8; 2,1 ± 1,2 y 1,8 ± 1 mg/dl, respectivamente (p < 0,001). Al 56,9% de los pacientes (N = 350) se les monitorizó los anticuerpos anti-HLA. El 94% (N = 329) no presentaron cambios en los anti-HLA, mientras que el 6% (N = 21) los positivizaron. De entre los pacientes con anticuerpos donante-específicos post-COVID19 (N = 9), a 7 pacientes (3,1%) se les había suspendido un inmunosupresor (en 5 de ellos se suspendió ácido micofenólico y en 2 tacrolimus), a un paciente los 2 inmunosupresores (3,4%) y al otro paciente no se le había modificado la inmunosupresión (1,1%), siendo estas diferencias no significativas. Conclusiones: el manejo de la inmunosupresión tras el diagnóstico de COVID19 se basó fundamentalmente en la suspensión de ácido micofenólico con reducciones o suspensiones muy discretas de inhibidores de calcineurina. Este manejo de la inmunosupresión no influyó en la función renal ni en cambios de los anticuerpos anti-HLA a los 6 meses del diagnóstico
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