1,721,068 research outputs found
Influence of tonsillectomy on the progression of mesangioproliferative glomerulonephritis
No full textNephrol Dial Transplant. 2010 Aug;25(8):2583-9. Epub 2010 Mar 2.
Influence of tonsillectomy on the progression of mesangioproliferative glomerulonephritis.
Piccoli A, Codognotto M, Tabbi MG, Favaro E, Rossi B.
Source
Department of Medical and Surgical Sciences, Nephrology Clinic, University of Padova, Padova, Italy. [email protected]
Abstract
BACKGROUND:
Little information is available about the efficacy of tonsillectomy on long-term renal survival of patients with primary IgA nephropathy (IgAN).
METHODS:
In this retrospective cohort study, we considered 61 patients with IgAN who had tonsillectomy (n = 15) or not (n = 46) and compared them with 121 control patients with mesangioproliferative glomerulonephritis (MesGN) free of IgA deposits, who had tonsillectomy (n = 49) or not (n = 72). We evaluated the progression from a normal function [estimated glomerular filtration rate 60-220 mL/min/1.73 m(2), chronic kidney disease (CKD) stage 1 and 2] to a moderate renal dysfunction in CKD stage 3, which was considered the outcome.
RESULTS:
The mean duration of follow-up was 250 months (12-300 months) in the whole group of 182 patients. The survival to progression to stage 3 was 88% after 10 years, 71% after 20 years and 53% after 25 years. It was 72% after 20 years in both groups. Tonsillectomy was not significantly associated with CKD progression. Significant prognostic factors were age (P = 0.01), initial CKD stage (P = 0.03), proteinuria (P = 0.03), persistent proteinuria (P < 0.001) and diastolic blood pressure (P = 0.01). In the multivariate analysis (Cox model), there was no significant effect of tonsillectomy adjusted for the type of glomerulonephritis, initial CKD stage, persistent proteinuria, diastolic blood pressure and age. Only persistent proteinuria adjusted for the other factors was significantly associated with CKD progression (hazard ratio of 6.2, 95% confidence interval 3.1-12.7, P < 0.001).
CONCLUSIONS:
Tonsillectomy was not associated with a different progression rate of IgAN nor of MesGN after 20 years of follow-up
Asymmetry of the total body water prediction bias using the impedance index.
No full textOur purpose was to prove on a geometric basis that the bias of total body water (TBW) prediction equations based on the impedance index is far greater in fluid overloading than in dehydration. We used formal evaluation of conventional bioimpedance regression equations in both normal and abnormal body fluid status. We plotted the hyperboloid function generated from a standard prediction equation for the TBW over the resistance-reactance (RXc) plane containing the bivariate tolerance intervals (ellipses) of the healthy population. The equation estimated 35 L TBW for the average man (both sexes) of 170 cm height. Leaving the center of the tolerance ellipses, over which the function was relatively flat, the predicted TBW rapidly increased to absurd values for the shorter vectors, indicating fluid overloading (e.g., > 100 L for R 850 ohm). Different formulas produced TBW prediction bias of the same order. Due to the hyperbolic shape, functions of the impedance index are critically dependent on the region of the RXc plane where they are calculated and they produce misleading results in patients with fluid overload
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
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
A decision analysis comparing three dosage regimens of subcutaneous epoetin in continuous ambulatory peritoneal dialysis.
No full textEpoetin (recombinant human erythropoietin; EPO) therapy adds a significant cost to the management of end-stage renal disease, the majority of the extra expense being attributable to its acquisition cost. In a Japanese multicentre, randomised, prospective study, a significant dose-dependent response was documented with epoetin given subcutaneously (SC) once a week or once every 2 weeks to patients receiving continuous ambulatory peritoneal dialysis. Three different dosages were studied over 5 months in patients with a haematocrit (Hct) of 0.28 or less, namely 6000U (107 U/kg), 9000U (167 U/kg) and 12 000U (211 U/kg). Epoetin was given weekly for the first 2 months until the target Hct value of 0.33 was reached.
The rates of response were 81, 85 and 100% with the 6000U, 9000U and 12 000U regimens, respectively. Subsequently, responders were maintained at the target Hct for an additional 3 months, with the administration frequency eventually being reduced to fortnightly or 4-weekly. Patients in the epoetin 6000U and 9000U groups who did not respond after 2 months' treatment underwent induction and maintenance with the 12 000U regimen.
During the maintenance phase, patients receiving the epoetin 6000U and 9000U dosages required weekly (54 and 64%, respectively) or fortnightly (46 and 36%, respectively) injections. Patients receiving the 12 000U regimen were found to require weekly (9%), fortnightly (73%) or 4-weekly (18%) injections.
Using these data, we performed a decision analysis that quantitatively incorporated the probability of attaining and maintaining target Hct levels in all patients (i.e. the effectiveness of epoetin), and direct costs as a function of both cumulative doses and injections required in all 3 strategies over 5 months.
Decision analysis indicated that the most cost-effective SC epoetin strategy in patients undergoing peritoneal dialysis is epoetin 6000U weekly for 2 months, followed by maintaining the target Hct with weekly or 2-weekly epoetin 6000U for the next 3 months. Nonresponders should restart epoetin therapy using the 12 000U strategy. The 9000U and 12 000U strategies were associated with similar costs, because the economic advantages associated with the lower administration frequency of the 9000U regimen compared with the 6000U regimen were offset by its higher cumulative acquisition cost. In other words, decision analysis indicated that the most cost-effective strategy was to use the lowest effective dose, reserving the highest dosage for patients who do not respond after 2 months.
The superiority of this strategy was confirmed by a sensitivity analysis performed on the cost of drug administration, which was varied from zero to $US60 per dose. In addition, consistent results were obtained when the analysis was extended to cover a 1-year treatment period with all 3 strategies
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