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Hollow-Fiber Dialyzer Employing Vitamin E-Bonded Membrane: A Morphological Analysis
No full textNo abstract available
HEMOREOLOGIC PROFILE OF KIDNEY TRANSPLANT RECIPIENTS: A ROLE IN CARDIOVASCULAR RISK?
No full textIntroduction and Aims: Hemorheology evaluates blood flow properties and mainly focuses on the study of blood viscosity and erythrocyte’s deformability. Flow properties are main determinants of an adequate tissue perfusion and their alterations play a significant role in cardiovascular diseases occurrence through endothelium damage and subsequent fibrosis with progression to end-organ injury.Patients with end stage renal disease (ESRD) undergoing dialysis present a CV risk of death 10-20 fold higher than the general population but also kidney transplantation (KT), being the optimal therapy for ESRD, keeps an higher CV risk compared to general population.Hemorheologic profile alterations have been described in ESRD patients but comprehensive data on KT recipients are missing. Aim of our study is to characterize the hemorheologic profile of KT recipients, and to compare these data with healthy volunteers and HD patients.
Methods: We investigated 47 healthy volunteers, 90 uremic patients undergoing intermittent HD, 108 kidney transplant recipients (KT) testing as hemorheologic parameters: plasma viscosity (ηP), whole blood viscosity (expressed as low shear rate (ηS1) or high shear rate (ηS200), erythrocyte aggregation index (EAI), flow limit (t0: as minimum strenght to be applied to blood fluid in order to start to flow), erythrocyte deformability (ED) evaluated by Taylor factor (Tk) [1-(ηP/ηS200)0.4/Ht], viscous-elastic blood behavior (as elastic module G’: fluid response to a preset and increasing strain using a oscillating pattern). All measurements were performed with a Haake Rotovisco RV20 Rheometer.
Results: We confirmed alterations of the hemorheologic profile in HD patients both before and after the dialytic session. KT, when compared to results obtained before HD treatments , normalizes many hemorheological parameters:ηP (1,35 ± 0,13 mPa*s vs 1,57 ± 0,23 mPa*s; p<0,05), ηS1 (12,57 ± 3,87 mPa*s vs 26,45 ± 11,79; p<0,05), ηS200 (3,96 ± 0,46 mPa*s vs 4,74 ± 1,08 mPa*s; p <0,05), EAI (KT 3,11 ± 0,89 vs 6,11 ± 2,25; p<0,05), t0 (0,12 ± 0,08 mPa vs 0,18 ± 0,06; p<0,05).However, KT show a markedly lower ED when compared to HD, as estimated with Tk (0,85 ± 0,10 vs 0,81 ± 0,09; p<0,05), and this data is confirmed by viscous-elastic blood behaviour with higher G’ in KT than in HD as from figure 1.
Conclusions: HD patients show various hemorheologic profile alterations; this could support the extremely high incidence of CV complications in these patients, involving large vessels (hS1), myocardial hypertrophy (t0), small vessels and microcirculation (hS200, Tk, EAI).KT improves most hemorheologic alterations found in HD, justifying a global reduction in CV risk. However ED is reduced in KT (higher Tk and G’), and this alteration could act as a detrimental injury at the microcircolatory level, damaging the endothelium and, through its activation, leading to a progression of end-organ damage in KT patients.As a matter of fact an impaired ED could contribute to progression of interstitial fibrosis and tubular atrophy (IFTA); effects of different antirejection drugs represent a further stimulating point to be addressed
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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