Cohort profile: Canadian study of prediction of death, dialysis and interim cardiovascular events (CanPREDDICT)

Background: The Canadian Study of Prediction of Death, Dialysis and Interim Cardiovascular Events (CanPREDDICT) is a large, prospective, pan-Canadian, cohort study designed to improve our understanding of determinants of renal and cardiovascular (CV) disease progression in patients with chronic kidney disease (CKD). The primary objective is to clarify the associations between traditional and newer biomarkers in the prediction of specific renal and CV events, and of death in patients with CKD managed by nephrologists. This information could then be used to better understand biological variation in outcomes, to develop clinical prediction models and to inform enrolment into interventional studies which may lead to novel treatments. Methods/Designs: Commenced in 2008, 2546 patients have been enrolled with eGFR between 15 and 45 ml/min 1.73m2 from a representative sample in 25 rural, urban, academic and non academic centres across Canada. Patients are to be followed for an initial 3 years at 6 monthly intervals, and subsequently annually. Traditional biomarkers include eGFR, urine albumin creatinine ratio (uACR), hemoglobin (Hgb), phosphate and albumin. Newer biomarkers of interest were selected on the basis of biological relevance to important processes, commercial availability and assay reproducibility. They include asymmetric dimethylarginine (ADMA), N-terminal pro-brain natriuretic peptide (NT-pro-BNP), troponin I, cystatin C, high sensitivity C-reactive protein (hsCRP), interleukin-6 (IL6) and transforming growth factor beta 1 (TGFβ1). Blood and urine samples are collected at baseline, and every 6 monthly, and stored at −80°C. Outcomes of interest include renal replacement therapy, CV events and death, the latter two of which are adjudicated by an independent panel. Discussion: The baseline distribution of newer biomarkers does not appear to track to markers of kidney function and therefore may offer some discriminatory value in predicting future outcomes. The granularity of the data presented at baseline may foster additional questions. The value of the cohort as a unique resource to understand outcomes of patients under the care of nephrologists in a single payer healthcare system cannot be overstated. Systematic collection of demographic, laboratory and event data should lead to new insights. The mean age of the cohort was 68 years, 90% were Caucasian, 62% were male, and 48% had diabetes. Forty percent of the cohort had eGFR between 30–45 mL/min/1.73m2, 22% had eGFR values below 20 mL/min/1.73m2; 61% had uACR < 30. Serum albumin, hemoglobin, calcium and 25-hydroxyvitamin D (25(OH)D) levels were progressively lower in the lower eGFR strata, while parathyroid hormone (PTH) levels increased. Cystatin C, ADMA, NT-proBNP, hsCRP, troponin I and IL-6 were significantly higher in the lower GFR strata, whereas 25(OH)D and TGFβ1 values were lower at lower GFR. These distributions of each of the newer biomarkers by eGFR and uACR categories were variable

Influência dos atributos do solo sobre a qualidade da madeira de Pinus taeda para produção de celulose kraft.

Neste trabalho foram analisados os efeitos dos atributos do solo sobre a qualidade da madeira de Pinus taeda para produção de celulose Kraft, em áreas da Klabin, em Telêmaco Borba-PR. Foram estudados oito sítios com árvores de 12 anos de idade, selecionados pelo tipo de solo, textura e vegetação primária. Para caracterização dos sítios foram realizadas coletas de amostras em três horizontes, tendo sido coletadas amostras indeformadas e compostas, analisando-se as seguintes variáveis no solo: densidade global, porosidade total, macroporosidade, disponibilidade de água, fertilidade e granulometria. Selecionaram-se cinco árvores médias por sítio, nas quais forma medidos as alturas total e comercial e o DAP e retirados discos, sendo este material ensaiado quanto a densidade básica, composição química, características morfológicas dos traqueídeos e produção de celulose Kraft. Com relação às propriedades da madeira, os atributos físicos do solo demonstraram ter maior influência. De modo geral, as madeiras provenientes de sítios com texturas mais argilosas apresentaram menores valores de densidade básica; maiores teores de extrativos e lignina; menores teores de holocelulose e celulose; traqueídeos mais curtos, masi largos, com paredes mais finas e com diâmetros do lúmen maiores; e menor rendimento em celulose. A partir destes resultados, concluiu-se ser possível a previsão de propriedades da polpa através da análise das características da madeira associada às condições edáficas reinantes

Influência dos atributos do solo sobre a produtividade de Pinus taeda.

O presente trabalho analisou os efeitos dos atributos do solo sobre a produtividade de Pinus taeda, em áreas da Klabin, em Telêmaco Borba, PR. Foram analisados oito sítios com árvores de 12 anos de idade, os quais foram selecionados pelo tipo de solo, textura e vegetação primária. Para a caracterização dos sítios foram realizadas coletas de amostras em três profundidades, sendo coletadas amostras indeformadas e amostras compostas, analisando-se as seguintes variáveis no solo: densidade global, porosidade total, macroporosidade, disponibilidade de água, fertilidade e granulometria. Selecionaram-se cinco árvores médias por sítio, nas quais foram medidas altura total, altura comercial e DAP. Os resultados foram: solos de textura argilosa, independentemente da classe a que pertencem, os quais propiciaram maiores produtividades do Pinus taeda. Percebeu-se, de maneira geral, que essa produtividade é afetada pelas alterações geradas nos atributos físicos e químicos do solo, o que contraria vários estudos, que confirmaram que os atributos químicos do solo só apresentavam efeitos sobre a produtividade quando considerados em conjunto

Urinary, Plasma, and Serum Biomarkers’ Utility for Predicting Acute Kidney Injury Associated With Cardiac Surgery in Adults: A Meta-analysis

BackgroundEarly accurate detection of acute kidney injury (AKI) occurring after cardiac surgery may improve morbidity and mortality. Although several novel biomarkers have been developed for the early detection of AKI, their clinical utility in the critical intraoperative and immediate postoperative period remains unclear.Study DesignSystematic review and meta-analysis.Setting & PopulationAdult patients having cardiac surgery.Selection Criteria for StudiesEMBASE, CINAHL, Cochrane Library, Scopus, and PubMed from January 1990 until January 2015 were systematically searched for cohort studies reporting the utility of novel biomarkers for the early diagnosis of AKI after adult cardiac surgery. Reviewers extracted data for study design, population, timing of biomarker measurement and AKI occurrence, biomarker performance (area under the receiver operating characteristic curve [AUROC]), and risk of bias.Index TestsNovel urine, plasma, and serum AKI biomarkers, measured intraoperatively and in the early postoperative period (<24 hours).Reference TestsAKI was defined according to the RIFLE, AKIN, or 2012 KDIGO criteria.ResultsWe found 28 studies reporting intraoperative and/or early postoperative measurement of urine (n=23 studies) or plasma or serum (n=12 studies) biomarkers. Only 4 of these studies measured biomarkers intraoperatively. Overall, intraoperative discrimination by the urine biomarkers neutrophil gelatinase-associated lipocalin (NGAL) and kidney injury marker 1 (KIM-1) demonstrated AUROCs<0.70, whereas N-acetyl-β-d-glucosaminidase (NAG) and cystatin C had AUROCs<0.75. In the immediate 24-hour postoperative period, the urine biomarkers NGAL (16 studies), KIM-1 (6 studies), and liver-type fatty acid binding protein (6 studies) exhibited composite AUROCs of 0.69 to 0.72. The composite AUROCs for postoperative urine cystatin C, NAG, and interleukin 18 were ≤0.70. Similarly, the composite AUROCs for postoperative plasma NGAL (6 studies) and cystatin-C (5 studies) were <0.70.LimitationsHeterogeneous AKI definitions.ConclusionsIn adults, known urinary, plasma, and serum biomarkers of AKI possess modest discrimination at best when measured within 24 hours of cardiac surgery

International practice patterns and factors associated with non-conventional hemodialysis utilization

<p>Abstract</p> <p>Background</p> <p>The purpose of our study was to determine characteristics that influence the utilization of non-conventional hemodialysis (NCHD) therapies and its subtypes (nocturnal (NHD), short daily (SDHD), long conventional (LCHD) and conventional hemodialysis (CHD) as well as provider attitudes regarding the evidence for NCHD use.</p> <p>Methods</p> <p>An international cohort of subscribers of a nephrology education website <url>http://www.nephrologynow.com</url> was invited to participate in an online survey. Non-conventional hemodialysis was defined as any forms of hemodialysis delivered > 3 treatments per week and/or > 4 hours per session. NHD and SDHD included both home and in-centre. Respondents were categorized as CHD if their centre only offered conventional thrice weekly hemodialysis. Variables associated with NCHD and its subtypes were determined using multivariate logistic regression analysis. The survey assessed multiple domains regarding NCHD including reasons for initiating and discontinuing, for not offering and attitudes regarding evidence.</p> <p>Results</p> <p>544 surveys were completed leading to a 15.6% response rate. The final cohort was limited to 311 physicians. Dialysis modalities utilized among the respondents were as follows: NCHD194 (62.4%), NHD 83 (26.7%), SDHD 107 (34.4%), LCHD 81 (26%) and CHD 117 (37.6%). The geographic regions of participants were as follows: 11.9% Canada, 26.7% USA, 21.5% Europe, 6.1% Australia/New Zealand, 10% Africa/Middle East, 10.9% Asia and 12.9% South America. Variables associated with NCHD utilization included NCHD training (OR 2.47 CI 1.25-4.16), government physician reimbursement (OR 2.66, CI 1.11-6.40), practicing at an academic centre (OR 2.28 CI 1.25-4.16), higher national health care expenditure and number of ESRD patients per centre. Hemodialysis providers with patients on NCHD were significantly more likely to agree with the statements that NCHD improves quality of life, improves nutritional status, reduces EPO requirements and is cost effective. The most common reasons to initiate NCHD were driven by patient preference and the desire to improve volume control and global health outcomes.</p> <p>Conclusion</p> <p>Physician attitudes toward the evidence for NCHD differ significantly between NCHD providers and conventional HD providers. Interventions and health policy targeting these areas along with increased physician education and training in NCHD modalities may be effective in increasing its utilization.</p