Patients' experiences of peritoneal dialysis at home: a phenomenological approach

The aim of this study was to highlight the meaning of home dialysis as experienced by patients with chronic renal failure. The research design was influenced by Ricoeur´s phenomenology. Nineteen patients from a Brazilian public hospital were interviewed, from May to September 2009. Interviews were guided by the question: "Tell me about your experiences lived undergoing PD". Findings unveiled the patients' perception of the drastic changes in their existence, consequent to disease and treatment; and the perception of themselves in that process. The feeling of anguish, physical pain and deprivations were part of living that condition. They foresee an uncertain future, depending on the expertise of health care providers and the demands on support of significant others. Findings suggest that individual aspects of patients' experiences must be considered if health care providers are to facilitate positive health outcomes.El objetivo de este estudio fue comprender la experiencia de la diálisis peritoneal domiciliaria, a partir de la narración de los pacientes. El abordaje del estudio se inspiró en la fenomenología hermenéutica de Paul Ricoeur. Fueron entrevistados 19 pacientes en la unidad de hemodiálisis de un hospital público brasileño, de marzo a septiembre de 2009. Las entrevistas fueron orientadas por la pregunta: describa su experiencia en la diálisis peritoneal. Los resultados revelaron la percepción de los participantes sobre el significado de la enfermedad en sus vidas y las drásticas transformaciones personales sufridas en ese proceso. Sentimientos de angustia y dolor física fueron acompañados por importantes limitaciones personales y sociales, impuestas por el tratamiento. Ellos esperan un futuro desconocido, reconociendo su dependencia de la ayuda de los familiares y de los profesionales de la salud. Los resultados revelan las dificultades y la falta de perspectivas experimentadas por los pacientes en diálisis, demostrando el papel crucial que le cabe a los profesionales que los acompañan. Ayudarlos a desarrollar el autocuidado y maximizar su calidad de vida es una prioridad en la asistencia a esos pacientes.O objetivo deste estudo foi compreender a experiência da diálise peritoneal domiciliar, a partir da narrativa dos pacientes. A abordagem do estudo inspirou-se na fenomenologia hermenêutica de Paul Ricoeur. Foram entrevistados 19 pacientes na unidade de hemodiálise de um hospital público brasileiro, de março a setembro de 2009. As entrevistas foram orientadas pela questão: descreva sua experiência na diálise peritoneal. Os resultados desvelaram a percepção dos participantes sobre o significado da doença em suas vidas e as drásticas transformações pessoais sofridas nesse processo. Sentimentos de angústia e dor física foram acompanhados por importantes limitações pessoais e sociais, impostas pelo tratamento. Eles esperam por um futuro incerto, reconhecendo sua dependência da ajuda dos familiares e dos profissionais da saúde. Os resultados desvelam as dificuldades e a falta de perspectivas vividas pelos pacientes em diálise, demonstrando o papel crucial que cabe aos profissionais que os acompanham. Ajudá-los a desenvolver o autocuidado e maximizar sua qualidade de vida é prioridade na assistência a esses pacientes

Cosmic ray oriented performance studies for the JEM-EUSO first level trigger

JEM-EUSO is a space mission designed to investigate Ultra-High Energy Cosmic Rays and Neutrinos (E > 5 ⋅ 1019 eV) from the International Space Station (ISS). Looking down from above its wide angle telescope is able to observe their air showers and collect such data from a very wide area. Highly specific trigger algorithms are needed to drastically reduce the data load in the presence of both atmospheric and human activity related background light, yet retain the rare cosmic ray events recorded in the telescope. We report the performance in offline testing of the first level trigger algorithm on data from JEM-EUSO prototypes and laboratory measurements observing different light sources: data taken during a high altitude balloon flight over Canada, laser pulses observed from the ground traversing the real atmosphere, and model landscapes reproducing realistic aspect ratios and light conditions as would be seen from the ISS itself. The first level trigger logic successfully kept the trigger rate within the permissible bounds when challenged with artificially produced as well as naturally encountered night sky background fluctuations and while retaining events with general air-shower characteristics

Bioaccumulation and trophic transfer of mercury in striped bass (Morone saxatilis) and tautog (Tautoga onitis) from the Narragansett Bay (Rhode Island, USA)

We examined the bioaccumulation and trophic transfer of mercury in two marine finfish species, striped bass (Morone saxatilis) and tautog (Tautoga onitis), collected from the Narragansett Bay (Rhode Island, USA). For each of these target fish, white muscle tissue was analyzed for total mercury (Hg) and results were evaluated relative to fish age, body size, and Hg content of preferred prey. Dietary and stable isotope analysis was also used to elucidate the effect of trophic processes on Hg concentrations in fish. The Hg content of muscle tissue was positively correlated with fish age and length for both species, although striped bass accumulated Hg faster than tautog. Accelerated Hg bioaccumulation in striped bass is consistent with its high trophic level (trophic level = 4.07) and Hg-enriched prey (forage fish and macrocrustaceans; mean Hg content = 0.03 mg Hg kg wet wt-1). In contrast, tautog maintain a lower trophic status (trophic level = 3.51) and consume prey with lower Hg levels (mussels and crabs; mean Hg content = 0.02 mg Hg kg wet wt-1). Despite differences in Hg bioaccumulation between target fish, the mean Hg concentration of tautog exceeded levels in striped bass (0.24 and 0.16 mg Hg kg wet wt-1, respectively) due to a disparity in age-at-catch between sampled groups (mean age of tautog and bass = 11.3 and 4.3 yr, respectively). Taking into account legal minimum catch lengths further revealed that 75.0% of legal-size striped bass (\u3e70.2 cm TL; n = 4) and 44.8% of tautog (\u3e40.6 cm TL; n = 29) had Hg levels beyond the US EPA regulatory threshold of 0.3 mg Hg kg wet wt-1. Moreover, Hg-length relationships suggest that each target fish meets this threshold near their minimum legal catch length. Our findings reiterate the value of species ecology to improve predictions of fish Hg and permit better management of human contamination by this important dietary source. © 2008 Elsevier Ltd. All rights reserved

Assessment of nonlethal methods for predicting muscle tissue mercury concentrations in coastal marine fishes

Caudal fin clips and dorsolateral scales were analyzed as a potential nonlethal approach for predicting muscle tissue mercury (Hg) concentrations in marine fish. Target fish were collected from the Narragansett Bay (Rhode Island, USA) and included black sea bass Centropristis striata [n = 54, 14-55 cm total length (TL)], bluefish Pomatomus saltatrix (n = 113, 31-73 cm TL), striped bass Morone saxatilis (n = 40, 34-102 cm TL), summer flounder Paralichthys dentatus (n = 64, 18-55 cm TL), and tautog Tautoga onitis (n = 102, 27-61 cm TL). For all fish species, Hg concentrations were greatest in muscle tissue [mean muscle Hg = 0.47-1.18 mg/kg dry weight (dw)] followed by fin clips (0.03-0.09 mg/kg dw) and scales (0.01-0.07 mg/kg dw). The coefficient of determination (R2) derived from power regressions of intraspecies muscle Hg against fin and scale Hg ranged between 0.35 and 0.78 (mean R2= 0.57) and 0.14-0.37 (mean R 2= 0.30), respectively. The inclusion of fish body size interaction effects in the regression models improved the predictive ability of fins (R 2= 0.63-0.80; mean = 0.71) and scales (R2= 0.33-0.71; mean = 0.53). According to the high level of uncertainty within the regression models (R2 values) and confidence interval widths, scale analysis was deemed an ineffective tool for estimating muscle tissue Hg concentrations in the target species. In contrast, the examination of fin clips as predictors of muscle Hg had value as a cursory screening tool; however, this method should not be the foundation for developing human consumption advisories. It is also noteworthy that the efficacy of these nonlethal techniques was highly variable across fishes and likely depends on species-specific life-history characteristics. © Springer Science+Business Media New York 2013

Update on the challenging role of biofilms in peritoneal dialysis

Biofilms are commonly associated with an increased risk of patient infection. In peritoneal dialysis (PD), catheter associ- ated infection, especially peritonitis, remains a clinically relevant problem. Although the presence of a biofilm is recog- nized in relapsing, repeat, and catheter-related peritonitis, it remains poorly characterized. In this review, an update on the role of biofilms in PD infections is presented. The emerging concept that host cells and tissue associated biofilms, in addition to the biofilms on the catheters themselves, contribute to the recalcitrance of infections is discussed. Further- more, the evidence of biofilms on PD catheters, their developmental stages, and the possible influence of the PD envi- ronment are reviewed. The focus is given to ex vivo and in vitro studies that contribute to the elucidation of the interplay between host, microbial, and dialysis factors. The key issues that are still to be answered and the challenges to clinical practice are discussed.Sociedade Portuguesa de Nefrologi