527 research outputs found
Definizione, studio e progetto preliminare di una tecnica di geo-localizzazione di sorgenti interferenti per satelliti commerciali di telecomunicazioni
No full textL’argomento del dottorato riguarda le telecomunicazioni satellitari commerciali. In particolare tratta della possibilità di poter definire, progettare e valutare mediante analisi e simulazioni, un sistema in grado di geo-localizzare sorgenti interferenti nell’area di copertura dell’antenna a bordo satellite per telecomunicazioni (area di servizio).
Tale soluzione tecnologica rappresenta un valido supporto per intervenire a seguito di uno o più eventi interferenti. Tale intervento può essere o di tipo passivo, quanto il satellite non è provvisto di sotto-sistema di contromisura, oppure attivo quando il satellite è provvisto a bordo di sistema di contromisura
Biomarkers and Precision Medicine in IgA Nephropathy
No full textThe field of biomarker research in IgA nephropathy has experienced a major boost in recent years with the publication of a large number of scientific reports. Candidate biomarkers from blood, urine, and renal tissue obtained through the use of clinical chemistry, molecular biology, and omics have been proposed for translation in clinical practice. Nevertheless, individual biomarkers often lack sensitivity and specificity with the consequent impairment of disease specificity. This review, moving on from the analysis of the four-hit hypothesis, illustrates the biomarkers linked to the abnormal glycosylation process of IgA1 and the immune complex formation. It also describes other serum and urinary biomarkers. Given the profound insights into the pleiotropic function of a single biomarker that is specific for a pathophysiological mechanism, this review suggests a novel approach based on a panel of biomarkers that covers the entire pathogenic process of the disease. Clinical bioinformatics that integrate genetic, clinical, and bioinformatics data sets could optimize the specific value of each biomarker in a multimarker panel. This is a promising approach for precision medicine and personalized therapy in IgA nephropathy. (C) 2018 Elsevier Inc. All rights reserved
MicroRNAs in glomerular diseases from pathophysiology to potential treatment target
No full textMiRNAs are regulators of gene expression in diverse biological and pathological courses in life. Their discovery may be considered one of the most important steps in the story of modern biology. miRNAs are packed within exosomes and released by cells for cellular communications; they are present in bodily fluids. Their study opens the way for understanding the pathogenetic mechanisms of many diseases; furthermore, as potential candidate biomarkers, they can be measured in bodily fluids for non-invasive monitoring of disease outcomes. The present review highlights recent advances in the role of miRNAs in the pathogenesis of primary and secondary glomerulonephritides such as IgA nephropathy, focal segmental glomerular sclerosis, lupus nephritis and diabetic nephropathy. The identification of reciprocal expression of miRNAs and their target genes provides the molecular basis for additional information on the pathogenetic mechanisms of kidney diseases. Finally, recent findings demonstrate that miRNAs can be considered as potential targets for novel drugs. © The Authors Journal compilatio
Is it time for personalized therapy in IgA nephropathy patients?
No full textRoccatello et al. [1] investigated the effectiveness and safety of mycophenolate mofetil (MMF) in combination with corticosteroids, compared to a 6-month course of glucocorticoids alone, in a group of 30 patients with proteinuric immunoglobulin A nephropathy (IgAN) who had active renal lesions (including proliferative endocapillary and extracapillary lesions and fibrinoid necrosis) identified through kidney biopsy. All patients received renin-angiotensin system blockers (RASBs) at the maximum tolerated dose as supportive therapy. The retrospective study demonstrated a significant reduction in proteinuria in both patient groups, with the mean follow-up period being 18.7 months for the first group receiving MMF in combination with corticosteroids, and 21.5 months for the group treated with corticosteroids alone. At the end of the follow-up period, the authors obtained a cumulative sparing dose of 6 g of corticosteroids in the group of patients who received the combined therapy (MMF and corticosteroids).
The study is limited by its retrospective design and the small number of patients included. However, it highlights two important points: first, the central importance of kidney biopsy in determining therapy for IgAN patients, and second, the potential for MMF to reduce the overall dose of corticosteroids required for treatment.
An international group of nephrologists dedicated 6 years (2004–2009) to developing the Oxford classification of the renal lesions in kidney biopsy from IgAN patients. Briefly, the classification is based on the grade of histological lesions as mesangial proliferation (M0,1), endocapillary proliferation (E0,1), glomerular sclerosis (S0,1) and tubulointerstitial lesions (T0,1,2). Eight years later, in 2017, the classification was revised and extracapillary proliferative lesions (C0,1,2) were included [2]. Thus, active renal lesions (E1 and C1,2) were differentiated from chronic renal lesions (T1,2). Unfortunately, the renal lesions were not considered in the first and second release of the KDIGO guidelines [3]. It is recommended that all patients receive intensive supportive therapy (renin-angiotensin system blockers) for at least 3–6 months following kidney biopsy. If the patient remains proteinuric (excreting more than 1 g per day) after this period, corticosteroids may be added to the treatment regimen. This means that active renal lesions become chronic in IgAN patients after 3 months of supportive therapy without immediate immunosuppressive therapy. This non-appropriate procedure has been adopted in all randomized clinical trials (RCTs) in the last 10 years, as shown in Table 1. The time lapse between the kidney biopsy and the randomization procedure fluctuated between 3 and 6 months of supportive therapy. All biopsy-proven IgAN patients (with active or chronic renal lesions) who were enrolled in those studies had chronic renal lesions because active renal lesions were not immediately treated with immunosuppressive therapy. There are several points to consider with this therapeutic approach. Firstly, corticosteroids may not be necessary for treating proteinuric IgAN patients with chronic renal lesions after supportive therapy. Newer drugs such as gliflozins and endothelin angiotensin receptor antagonists, when combined with RASBs, may effectively reduce proteinuria [4, 5]. Secondly, these drugs do not have to be limited to IgAN patients alone, but may also be used to treat other biopsy-proven chronic glomerular diseases. For example, sparsentan was initially shown to be effective and safe in patients with focal and segmental glomerular sclerosis [6] before being tested in IgAN patients [5]. Additionally, it is worth mentioning the targeted-release formulation, budesonide (Nefecon), a corticosteroid that has been shown to reduce proteinuria in IgAN patients. However, it is uncertain whether this drug can also reduce active renal lesions. It would be valuable to investigate the potential of Nefecon when combined with an antiproteinuric drug in treating IgAN patients with active renal lesions following kidney biopsy. Unfortunately, this hypothesis cannot be proved by the NEFIGAN and NEFIgArD studies because all patients received RASBs alone for at least 3 months before Nefecon therapy
Recensione a -AA.VV., San Francesco di Stampace. Il perchè di un recupero, Cagliari, 1986
No full textPotential Reparative Role of Resident Adult Renal Stem/Progenitor Cells in Acute Kidney Injury
No full textHuman kidney is particularly susceptible to ischemia and toxins with consequential tubular necrosis and activation of inflammatory processes. This process can lead to the acute renal injury, and even if the kidney has a great capacity for regeneration after tubular damage, in several circumstances, the normal renal repair program may not be sufficient to achieve a successful regeneration. Resident adult renal stem/progenitor cells could participate in this repair process and have the potentiality to enhance the renal regenerative mechanism. This could be achieved both directly, by means of their capacity to differentiate and integrate into the renal tissues, and by means of paracrine factors able to induce or improve the renal repair or regeneration. Recent genetic fate-tracing studies indicated that tubular damage is instead repaired by proliferative duplication of epithelial cells, acquiring a transient progenitor phenotype and by fate-restricted clonal cell progeny emerging from different nephron segments. In this review, we discuss about the properties and the reparative characteristics of high regenerative CD133(+)/CD24(+) cells, with a view to a future application of these cells for the treatment of acute renal injury
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