111,856 research outputs found
Treatment options for anemia in kidney transplant patients: a review
No full textAnemia is common after kidney transplantation. The etiology may be multifactorial
including both causes of anemia in the general population and more specific causes
unique to the kidney transplant setting. Post-transplant anemia, particularly when severe,
may be associated with adverse effects including graft failure, mortality, and a decline in
kidney function. After careful investigation, having excluded or treated reversible causes
of anemia, treatment of anemia in patients with a kidney transplant is based on iron
supplementation and/or erythropoiesis stimulating agents though there are no specific
guidelines on anemia management in this patient population. Iron therapy is often
needed, but optimal and safe iron deficiency management strategies remain to be defined.
Evidence suggests that erythropoiesis stimulating agents are safe and potentially
associated with favorable outcomes. Better graft function has been reported upon ESA
use targeting hemoglobin levels higher than those recommended in the general chronic
kidney disease population with no apparent increased risk of cardiovascular events. These
results require further investigation. Data on the use of hypoxia-inducible factor
inhibitors are limited. Prevention and treatment of anemia in kidney transplantation can
improve patients’ quality of life, life expectancy, allograft function, and survival
Examining hemodialyzer membrane performance using proteomic technologies
No full textMario Bonomini,1 Luisa Pieroni,2 Lorenzo Di Liberato,1 Vittorio Sirolli,1 Andrea Urbani2,3 1Department of Medicine, G. d’Annunzio University, Chieti, 2Proteomic and Metabonomic Units, IRCCS S. Lucia Foundation, Rome, 3Faculty of Medicine, Biochemistry and Clinical Biochemistry Institute, Catholic University of the “Sacred Heart”, Rome, Italy Abstract: The success and the quality of hemodialysis therapy are mainly related to both clearance and biocompatibility properties of the artificial membrane packed in the hemodialyzer. Performance of a membrane is strongly influenced by its interaction with the plasma protein repertoire during the extracorporeal procedure. Recognition that a number of medium–high molecular weight solutes, including proteins and protein-bound molecules, are potentially toxic has prompted the development of more permeable membranes. Such membrane engineering, however, may cause loss of vital proteins, with membrane removal being nonspecific. In addition, plasma proteins can be adsorbed onto the membrane surface upon blood contact during dialysis. Adsorption can contribute to the removal of toxic compounds and governs the biocompatibility of a membrane, since surface-adsorbed proteins may trigger a variety of biologic blood pathways with pathophysiologic consequences. Over the last years, use of proteomic approaches has allowed polypeptide spectrum involved in the process of hemodialysis, a key issue previously hampered by lack of suitable technology, to be assessed in an unbiased manner and in its full complexity. Proteomics has been successfully applied to identify and quantify proteins in complex mixtures such as dialysis outflow fluid and fluid desorbed from dialysis membrane containing adsorbed proteins. The identified proteins can also be characterized by their involvement in metabolic and signaling pathways, molecular networks, and biologic processes through application of bioinformatics tools. Proteomics may thus provide an actual functional definition as to the effect of a membrane material on plasma proteins during hemodialysis. Here, we review the results of proteomic studies on the performance of hemodialysis membranes, as evaluated in terms of solute removal efficiency and blood–membrane interactions. The evidence collected indicates that the information provided by proteomic investigations yields improved molecular and functional knowledge and may lead to the development of more efficient membranes for the potential benefit of the patient. Keywords: mass spectrometry, hemodialysis, end-stage renal disease, protein adsorption, biocompatibility, uremic toxi
Proteomics and nephrology
No full textProteome analysis has emerged as a new field of protein science offering the possibility of achieving unbiased identification, quantification and functional assessment of all proteins and peptides present in biological samples. Proteomics technologies are being used with increased frequency in the renal community. In this article we aim to highlight investigations in basic renal research and in clinical nephrology making use of recent developments in proteomic methods. Several examples are presented of how proteomics may be helpful to nephrology and affect possible future directions in kidney research
Blood cell proteomics in chronic kidney disease
No full textBackground: The uremic syndrome mimes a systemic poisoning with the retention of numerous compounds which are normally removed by the kidney. The study of proteins and peptides, or proteomics, represents an important field of research for the investigation of blood and blood diseases. Methods and Materials: We focused our review on the results of proteomic investigations on blood cells of uremic patients with particular regard to the study of red blood cells, platelets, and monocytes. Results: In literature there are few, preliminary studies on platelets and monocytes while the knowledge on uremic erythrocytes is much wider. Proteomic investigations showed that erythrocyte membrane proteome of uremic patients, differs significantly from the proteome of healthy subjects, being characterized by an extensive remodeling which may influence visco-elastic properties of RBC such as deformability and involve diverse molecular pathways driving red blood cell signaling and removal. Conclusion: Proteomic technologies emerged as a useful tool in defining and characterizing both physiological and disease processes being able, among others, to give important insights into uremic anemia. © 2018 Bonomini et al
Removal of uraemic plasma factor(s) using different dialysis modalities reduces phosphatidylserine exposure in red blood cells.
No full textBACKGROUND:
Solute(s) retained during uraemia cause increased exposure of aminophospholipid phosphatidylserine (PS) on the outer surface of erythrocyte membranes, and this phenomenon may be involved in the pathophysiology of uraemia by promoting abnormal erythrocyte interactions.
METHODS:
We examined in a prospective randomized cross-over fashion the ability of various dialysis modalities to remove the circulating uraemic factor(s) causing increased PS externalization in red cells. Each patient was treated with haemodialysis (HD) and with on-line haemodiafiltration (HDF) using standard high-flux polysulphone membranes or with the new polisulphone-based Helixone membrane to compare the effects of dialysis technique and membrane type on PS exposure. Removal of PS was assessed indirectly by measuring PS-expressing normal erythrocytes exposed to uraemic plasma or to ultrafiltrate obtained at various time points during the extracorporeal session.
RESULTS:
Removal of the uraemic plasma factor(s) causing PS exposure was demonstrated by the reduced ability of uraemic plasma at the end of dialysis to induce PS exposure in normal erythrocytes, and by the capacity of ultrafiltrate from the dialysate side of the dialyzer membrane to markedly increase PS-positive red cells. However, the degree of removal varied according to the dialyzer type and to dialysis technique. Removal was greater for on-line HDF using the Helixone membrane, intermediate and comparable with HD with Helixone and with on-line HDF using standard polysulphone, and lower for HD using polysulphone membrane. The putative uraemic compound causing PS exposure seems to be highly lipophilic, somehow associated with plasma proteins, and apparently having a molecular weight between 10 and 10.8 kDa.
CONCLUSIONS:
Uraemia is associated with retention of compound(s) that are lipophilic, possibly protein-bound and which cause an abnormal exposure of PS in erythrocytes. Our findings, that such compound(s) can be removed during dialysis and at higher rates with convection techniques, indicate a potential benefit for uraemic patients. The present results also seem to confirm the marked ability of high-flux Helixone membranes t
author-bios-SRD-19-0063.R1 – Supplemental material for The Network Structure of Police Misconduct
No full textSupplemental material, author-bios-SRD-19-0063.R1 for The Network Structure of Police Misconduct by George Wood, Daria Roithmayr and Andrew V. Papachristos in Socius</p
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe 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
Platelet activation and platelet-erytrocyte aggregates in end-stage renal disease patients on hemodialisis
No full textVariations on the Author
No full text“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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