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1.
Sci Total Environ ; 624: 1429-1442, 2018 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-29929254

RESUMEN

Mountain ecosystems are sensitive and reliable indicators of climate change. Long-term studies may be extremely useful in assessing the responses of high-elevation ecosystems to climate change and other anthropogenic drivers from a broad ecological perspective. Mountain research sites within the LTER (Long-Term Ecological Research) network are representative of various types of ecosystems and span a wide bioclimatic and elevational range. Here, we present a synthesis and a review of the main results from ecological studies in mountain ecosystems at 20 LTER sites in Italy, Switzerland and Austria covering in most cases more than two decades of observations. We analyzed a set of key climate parameters, such as temperature and snow cover duration, in relation to vascular plant species composition, plant traits, abundance patterns, pedoclimate, nutrient dynamics in soils and water, phenology and composition of freshwater biota. The overall results highlight the rapid response of mountain ecosystems to climate change, with site-specific characteristics and rates. As temperatures increased, vegetation cover in alpine and subalpine summits increased as well. Years with limited snow cover duration caused an increase in soil temperature and microbial biomass during the growing season. Effects on freshwater ecosystems were also observed, in terms of increases in solutes, decreases in nitrates and changes in plankton phenology and benthos communities. This work highlights the importance of comparing and integrating long-term ecological data collected in different ecosystems for a more comprehensive overview of the ecological effects of climate change. Nevertheless, there is a need for (i) adopting co-located monitoring site networks to improve our ability to obtain sound results from cross-site analysis, (ii) carrying out further studies, in particular short-term analyses with fine spatial and temporal resolutions to improve our understanding of responses to extreme events, and (iii) increasing comparability and standardizing protocols across networks to distinguish local patterns from global patterns.

2.
J Immunol Res ; 2017: 5201098, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28133619

RESUMEN

The purpose of the present review is to describe how we improve the model for risk stratification of transplant outcomes in kidney transplantation by incorporating the novel insights of donor-specific anti-HLA antibody (DSA) characteristics. The detection of anti-HLA DSA is widely used for the assessment of pre- and posttransplant risks of rejection and allograft loss; however, not all anti-HLA DSA carry the same risk for transplant outcomes. These antibodies have been shown to cause a wide spectrum of effects on allografts, ranging from the absence of injury to indolent or full-blown acute antibody-mediated rejection. Consequently, the presence of circulating anti-HLA DSA does not provide a sufficient level of accuracy for the risk stratification of allograft outcomes. Enhancing the predictive performance of anti-HLA DSA is currently one of the most pressing unmet needs for facilitating individualized treatment choices that may improve outcomes. Recent advancements in the assessment of anti-HLA DSA properties, including their strength, complement-binding capacity, and IgG subclass composition, significantly improved the risk stratification model to predict allograft injury and failure. Although risk stratification based on anti-HLA DSA properties appears promising, further specific studies that address immunological risk stratification in large and unselected populations are required to define the benefits and cost-effectiveness of such comprehensive assessment prior to clinical implementation.


Asunto(s)
Aloinjertos/inmunología , Rechazo de Injerto/inmunología , Antígenos HLA/inmunología , Trasplante de Riñón , Especificidad de Anticuerpos , Femenino , Rechazo de Injerto/prevención & control , Supervivencia de Injerto/inmunología , Humanos , Isoanticuerpos/sangre , Trasplante de Riñón/efectos adversos , Masculino , Factores de Riesgo , Donantes de Tejidos , Trasplante Homólogo
3.
Am J Transplant ; 16(5): 1596-603, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-26693703

RESUMEN

Complement inhibitors have not been thoroughly evaluated in the treatment of acute antibody-mediated rejection (ABMR). We performed a prospective, single-arm pilot study to investigate the potential effects and safety of C1 inhibitor (C1-INH) Berinert added to high-dose intravenous immunoglobulin (IVIG) for the treatment of acute ABMR that is nonresponsive to conventional therapy. Kidney recipients with nonresponsive active ABMR and acute allograft dysfunction were enrolled between April 2013 and July 2014 and received C1-INH and IVIG for 6 months (six patients). The primary end point was the change in eGFR at 6 months after inclusion (M+6). Secondary end points included the changes in histology and DSA characteristics and adverse events as evaluated at M+6. All patients showed an improvement in eGFR between inclusion and M+6: from 38.7 ± 17.9 to 45.2 ± 21.3 mL/min/1.73 m(2) (p = 0.0277). There was no change in histological features, except a decrease in the C4d deposition rate from 5/6 to 1/6 (p = 0.0455). There was a change in DSA C1q status from 6/6 to 1/6 positive (p = 0.0253). One deep venous thrombosis was observed. In a secondary analysis, C1-INH patients were compared with a similar historical control group (21 patients). C1-INH added to IVIG is safe and may improve allograft function in kidney recipients with nonresponsive acute ABMR.


Asunto(s)
Proteína Inhibidora del Complemento C1/uso terapéutico , Rechazo de Injerto/tratamiento farmacológico , Isoanticuerpos/inmunología , Fallo Renal Crónico/complicaciones , Trasplante de Riñón/efectos adversos , Adulto , Inactivadores del Complemento/uso terapéutico , Femenino , Estudios de Seguimiento , Tasa de Filtración Glomerular , Rechazo de Injerto/etiología , Supervivencia de Injerto/efectos de los fármacos , Humanos , Inmunoglobulinas Intravenosas/administración & dosificación , Fallo Renal Crónico/cirugía , Pruebas de Función Renal , Masculino , Persona de Mediana Edad , Proyectos Piloto , Pronóstico , Estudios Prospectivos , Factores de Riesgo
5.
Transpl Infect Dis ; 16(2): 344-6, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24628788

RESUMEN

Diarrhea is a frequent complication after kidney transplantation, with an incidence rate between 22% and 51%. In many cases, the cause remains unknown. We describe here the first case, to our knowledge, of persistent diarrhea associated with Coxsackievirus A19 (CVA19) in a kidney transplant recipient. The patient was a 46-year-old man who received a deceased-donor kidney. He experienced delayed graft function because of donor kidney donation after circulatory determination of death. Maintenance immunosuppression consisted of low-dose cyclosporine, high-dose mycophenolate mofetil (MMF) (3 g/day), and prednisone (10 mg/day). He had severe diarrhea for 2 weeks associated with acute renal failure. No pathogens were found in the stool cultures. Enterovirus detection was positive by real-time polymerase chain reaction, and sequence analysis found CVA19 (from Enterovirus C group). Area under the curve of MMF was 48 mg.h/L. Because of the persistence of diarrhea, MMF was stopped and replaced by azathioprine. The diarrhea disappeared, but serum creatinine did not return to baseline. CVA19 rarely causes gastroenteritis. This case illustrates that MMF is not always the direct cause of diarrhea, and that new clinical infectious diseases will be detected with the expansion of molecular-based DNA diagnostics.


Asunto(s)
ADN Viral/análisis , Diarrea/virología , Enteritis/virología , Enterovirus Humano C/aislamiento & purificación , Trasplante de Riñón/efectos adversos , Enterovirus Humano C/genética , Humanos , Masculino , Persona de Mediana Edad
6.
Transpl Infect Dis ; 14(5): E64-70, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22931551

RESUMEN

Parvovirus B19 (PB19) infection is known to cause acute erythroblastopenia-mediated anemia in solid organ transplant (SOT) recipients. Intravenous immunoglobulins (IVIg) and the decrease of immunosuppression level are supposed to induce a long-term remission, although no consensus exists about the dose and the schedule of IVIg administrations. However, a few reports have shown that PB19-related anemia can recur despite this treatment, with a maximum of 3 recurrences reported. In this report, we describe in detail the cases of 2 kidney recipients with PB19 infection. They experienced, respectively, 9 and 7 PB19-related anemia recurrences. Immunosuppression level was decreased and IVIg were administered at each recurrence followed by a transitory normalization of hemoglobin level and a decrease of serum PB19 viral load. Episodes were separated by several months. These patients raise an original therapeutic management question about a frequent viral infection in SOT recipients. One patient is currently receiving IVIg every 3 months as a secondary prophylaxis without recurrence to date. These 2 case reports are followed by a review of the literature.


Asunto(s)
Anemia/etiología , Trasplante de Riñón/efectos adversos , Infecciones por Parvoviridae/complicaciones , Infecciones por Parvoviridae/virología , Parvovirus B19 Humano/aislamiento & purificación , Adulto , Anemia/prevención & control , Humanos , Inmunoglobulinas Intravenosas/uso terapéutico , Masculino , Recurrencia
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