1,721,005 research outputs found
Kidney disease in Sant' Andrea Hospital. a biopsy based epidemiologic study [Studio epidemiologico sulle biopsie renali presso l’A. O. Sant’Andrea]
No full textQuesto studio valuta retrospettivamente la prevalenza delle nefropatie non neoplastiche diagnosticate nell’Azienda Ospedaliera Sant’Andrea da Gennaio 2003 ad Aprile 2015. Nel periodo oggetto di studio sono
state eseguite presso il nostro centro 246 biopsie renali. 195/246 casi sono risultati diagnostici di patologie renali non neoplastiche e quindi sono stati oggetto di ulteriori analisi. Il gruppo più cospicuo, similmente ai dati dei registri nazionali ed internazionali, è rappresentato dalle GN primitive. Tra queste, la patologia più frequente nella nostra casistica risulta la GN membranosa (20,4%), seguita dalla GN a depositi mesangiali di IgA (12,7%). La maggiore prevalenza della GN Membranosa rispetto alla GN a depositi mesangiali di IgA rappresenta un’ inversione di tendenza rispetto ai registri nazionali ed internazionali e può essere interpretata alla luce dell’età media dei pazienti sottoposti a biopsia renale nel nostro centro (54,1 anni). La GN Membranosa rappresenta infatti la causa più frequente di S. Nefrosica nell’età adulta. I pazienti affetti da nefropatia diabetica rappresentano una assoluta minoranza (1,5%). In 10/195 casi (5,1%) la biopsia renale ha evidenziato un quadro di nefropatia end stage. Questo studio epidemiologico rappresenta il punto di partenza per valutare la prevalenza delle diverse nefropatie, peril confronto con iregistri di biopsie renali presenti sul territorio nazionale ed internazionale e per l’acquisizione di informazioni sulla “politica bioptica” del centro oggetto di studio.The aim of this retrospective study is to investigate the prevalence and pathological features of kidney inflammatory nephropathies diagnosed in Sant'Andrea Hospital, from January 2003 to April 2015. In this period, 246 kidney biopsies have been diagnosed in our Hospital. Excluding cases of kidney neoplasms and non-diagnostic samples, 195 cases were reviewed. Primary glomerulonephritis (GN) is the most common diagnosis. Among these, Membranous GN represents the majority of cases (20.4%), followed by IgA Nephropathy (12.7%). The higher prevalence of Membranous GN than IgA Nephropathy represents a difference between our study and national and international kidney biopsies registries. It can be considered a consequence of the average age of patients undergoing renal biopsy in our center (54,1 years). Patients with Diabetic Nephropathy are 1.5%. 10 out of 195 cases (5.1%) show end stage renal disease. This epidemiological study evaluates the prevalence of various kidney diseases in our database, the biopsy policy of SantAndrea Hospital and compares our results with national and international renal biopsies registries
Renal involvement in adrenal insufficiency (Addison disease): can we always recognize it?
No full textAddison disease is due to the destruction or dysfunction of the entire adrenal cortex. Nowadays, the causes of adrenal insufficiency are autoimmune disease for 70–90% and tuberculosis for 7–20%. Many typical signs and symptoms, such as hyponatremia, hyperkalaemia, or renal insufficiency can represent the reasons for a nephrology consultation, especially in conditions of urgency, and they can easily be confused with other causes. Moreover, the fact that in a short time range we have diagnosed the three cases described as a guide in this review, has aroused our attention as nephrologists on a disease in which we have probably already encountered but without recognizing it. The blood tests showed in all three patients severe electrolyte disorders and acute renal failure which will be discussed in their physiopathogenetic mechanisms. In a peculiar way, these alterations were not controlled with repolarizing solutions, fluid replacement and increased volemia, but only after steroid administration. In conclusion, in this review all the known pathogenic mechanisms causing disorders of nephrological interest in adrenal insufficiency are discussed
CALCIUM RELEASE-ACTIVATED CALCIUM INFLUX IN CULTURED HUMAN MESANGIAL CELLS
No full textCa2+ influx is a major component of the response of cultured human mesangial cells (HMC) to vasoconstrictors. Activators of phospholipase C such as angiotensin II (Ang II) release Ca2+ from intracellular stores and enhance Ca2+ influx, which in turn is modulated by Na+/Ca2+ exchange. By microfluorometry we studied the mechanisms of Ca2+ entry in resting and stimulated fura-2-loaded monolayers or single HMC. Addition of 1 to 10 mM extracellular Ca2+ to cells equilibrated in Ca2+-free media resulted in a rapid, persistent elevation of free cytosolic Ca2+ ([Ca2+](i)), from 52 +/- 5 to 113 +/- 18 and 226 +/- 37 nM, respectively. Ca2+ influx was blocked by lanthanum or chelation with EGTA, while it was only partially inhibited by voltage-operated Ca2+ channel(VOC) blockers, such as nifedipine or verapamil. The rise of [Ca2+](i) at high external [Ca2+] was not due to a Ca2+-sensing mechanism with release of intracellularly stored Ca2+, since it was prolonged, and it was not seen in cells maintained in normal 1.25 mM [Ca2+] media. Moreover, it was not abolished by prior depletion of Ca2+ stores with 0.5 mu M thapsigargin or 5 mu M ionomycin in Ca2+-free media, which transiently increased [Ca2+](i) (to 281 +/- 39 and 380 +/- 51 nM, respectively). On the contrary, both agents markedly potentiated Ca2+ influx upon addition of 1 to 10 mM [Ca2+](c), (to a maximum of 686 +/- 111 and 633 +/- 150 nM, P < 0.05 vs. control). Prior stimulation of [Ca2+](i) with 1 mu M Ang II had similar effects, enhancing the subsequent Ca2+ influx to 241 +/- 42 (1 mM Ca2+) and 512 +/- 106 nM (10 mM Ca2+; P < 0.05). Enhancement of Ca2+ influx by thapsigargin, ionomycin and Ang II was confirmed by increased Mn2+ quenching of fura-2 fluorescence following addition of the agents in the absence of extracellular Ca2+. VOC activation by membrane depolarization was not responsible for such potentiation, since 50 mM KCl failed to modify Ca2+ influx. Na+/Ca2+ exchange was ruled out by persistence of influx after intracellular Na+ depletion. Thus, an initial elevation of [Ca2+](i) by vasoconstrictors, blockers of Ca2+ ATPase or Ca2+ ionophores enhances Ca2+ entry in HMC via a Ca2+ release-activated Ca2+ conductance, mostly independent of plasma membrane depolarization
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
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Prognostic value of high-sensitive cardiac troponin I in asymptomatic chronic hemodialysis patients
No full textIntroduction: Increased levels of cardiac troponins (cTn) are a hallmark of acute myocardial infarction (AMI), along with symptoms and electrocardiographic (ECG) changes. Stably elevated cTn concentrations are frequently observed in asymptomatic patients with chronic kidney disease (CKD) and/or on hemodialysis (HD); the meaning of this elevation, as assessed by conventional techniques, remains unclear. Aim of our study was to evaluate the clinical significance of cTnI levels in asymptomatic HD patients by employing a newer high-sensitive cTnI (hs-cTnI) assay. Methods: We enrolled 49 patients undergoing regular HD treatment for more than 3 months; all patients were asymptomatic for chest pain and had no history of acute coronary syndrome in the past 2 months. For every patient we measured hs-cTnI, cTnI and brain natriuretic peptide (BNP) before initiation of one HD session at baseline (T0), after 3 (T1) and 9 months (T2). Demographic, anamnestic, dialytic and echocardiographic characteristics of the examined population were evaluated. We also recorded the number of cardiovascular events from T0 to 12 months after T2. Results: Fifteen patients were lost to follow-up: 6 died, 2 underwent kidney transplantation, 7 did not match the inclusion criteria later during observation. At T0 (49 patients) we observed 14 hs-cTnI positive patients vs. 4 standard c-TnI positive patients (28,5% vs 8,1%); at T1 (40 patients) 16 vs 3 (26.4% vs 7.5%); at T2 (34 pz) 9 vs 0 (26.4% vs 0%). During the study we recorded 10 cardiovascular events, 8 of which in patients that were hs-cTNI positive, leading to death in 3. Hs-cTnI levels were predictive of cardiovascular events at all times and predictive of cardiovascular mortality at T0 and T1 (p < 0.001). In a multivariate analysis, a history of coronary artery disease (CAD) was an independent variable of high hs-cTnI levels at T0 (p < 0.04) and T1 (p < 0.03). Conclusions: Our study shows that a novel sensitive assay detects more asymptomatic HD patients compared to previously used methods, being at the same time predictive of cardiovascular mortality and morbidity. The only independent variable of high hs-cTnI concentrations was a positive history of cardiovascular disease, suggesting a possible role of hs-cTnI in identifying a high-risk subset of patients
Serum Cardiac Biomarkers in Asymptomatic Hemodialysis Patients. Role of Soluble Suppression of Tumorigenicity-2
No full textIntroduction: Cardiovascular events (CVE) remain the leading cause of mortality in hemodialysis (HD) patients. The ability to assess the risk of short-term CVE is of great importance. Soluble suppression of tumorogenicity-2 (sST2) is a novel biomarker that better stratifies risk of CVE than troponins in patients with heart failure. Few studies have investigated the role of sST2 in the HD population. The aim of this single-center study was to assess the predictive ability of sST2 on CVE in comparison to high-sensitive cardiac troponin I (hs-cTnI) and B-type natriuretic peptide (BNP) in HD patients. Methods: This study used a prospective, observational cohort design. We enrolled 40 chronic HD patients asymptomatic for chest pain and without recent history of acute coronary syndrome. We tested sST2 pre-/post-HD, hs-cTnI, and BNP. Demographic/dialytic/echocardiographic data were evaluated. We recorded the number of CVE for 12 months. The patients were classified into 2 groups: those who developed CVE and those who did not. Results: Ten of the 40 patients (25%) developed CVE during a 12-month follow-up. Increased sST2 levels (p < 0.0001) as well as hs-cTnI and BNP are predictive of CVE. When analyzing biomarkers as binary variables for values above or below the normal range, the correlation remained significant only for sST2 (p = 0.001). A small variation in sST2 levels before and after HD sessions was found (-2.1 ng/mL). sST2 was correlated with left ventricular (LV) echocardiographic data: LV mass index (p = 0.0001), LV ejection fraction (p = 0.01), and diastolic bulging of septum (p = 0.015). BNP and sST2 combination increased the prediction of CVE in a statistical model. Conclusion: Our study confirms that sST2 is useful for stratifying CV risk in the HD population. sST2 can be evaluated simply as a dichotomous value higher or lower than the normal range, making it easily interpretable. Dialysis and residual diuresis did not affect significantly sST2. A multimarker approach that incorporates sST2 and BNP may improve the prediction of CVE
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