The effect of combination treatment with aliskiren and blockers of the renin-angiotensin system on hyperkalaemia and acute kidney injury: systematic review and meta-analysis

Objective To examine the safety of using aliskiren combined with agents used to block the renin-angiotensin system

What Insights Do Patients and Caregivers Have on Acute Kidney Injury and Posthospitalization Care? A Single-Centre Qualitative Study from Toronto, Canada

Objectives Hospitalisation with acute kidney injury (AKI) is associated with short-term and long-term adverse events, but patient and caregiver experiences with AKI are not well described. We sought to better understand patient and caregiver perspectives after a hospitalisation with AKI to inform discharge strategies that may improve outcomes for this high-risk population. Design Qualitative study with semistructured interviews. Setting Tertiary care hospital in Toronto, Ontario, Canada. Participants Adult patients (n=15) who survived a hospitalisation with Kidney Disease Improving Global Outcomes stage 2 or 3 AKI from May to December 2016. We also interviewed five patient caregivers. We required patients to have no previous evidence of severe chronic kidney disease (ie, prior receipt of dialysis, previous kidney transplantation or pre-existing estimated glomerular filtration rate (eGFR) under 30 mL/min/1.73 m2). Results We identified three over-arching themes: (1) prioritisation of conditions other than AKI, reflected by the importance placed on other comorbidities and the omission of AKI as part of the ongoing medical history; (2) variability in comprehension of the significance of AKI, represented by minimal knowledge of the causes and symptoms associated with AKI, along with misinformation on the kidneys’ ability to self-repair; and (3) anxiety from discharge planning and competing health demands, illustrated by complicated discharge plans involving multiple specialist appointments. Conclusions Patients and caregivers view AKI as a short-term and reversible condition, giving it little thought during the postdischarge period. As a result, reliance on patients and caregivers to report an episode of AKI to their outpatient physicians is unlikely to be successful. Patient-centred tools and decision aids are needed to bridge the gap between a hospitalisation with AKI and the safe transition to the outpatient setting

The risk of stroke and stroke type in patients with atrial fibrillation and chronic kidney disease

Background: Atrial fibrillation (AF) and chronic kidney disease (CKD) are known to increase the risk of stroke. Objectives: We set out to examine the risk of stroke by kidney function and albuminuria in patients with and without AF. Design: Retrospective cohort study. Settings: Ontario, Canada. Participants: A total of 736 666 individuals (>40 years) from 2002 to 2015. Measurements: New-onset AF, albumin-to-creatinine ratio (ACR), and an estimated glomerular filtration rate (eGFR). Methods: A total of 39 120 matched patients were examined for the risk of ischemic, hemorrhagic, or any stroke event, accounting for the competing risk of all-cause mortality. Interaction terms for combinations of ACR/eGFR and the outcome of stroke with and without AF were examined. Results: In a total of 4086 (5.2%) strokes (86% ischemic), the presence of AF was associated with a 2-fold higher risk for any stroke event and its subtypes of ischemic and hemorrhagic stroke. Across eGFR levels, the risk of stroke was 2-fold higher with the presence of AF except for low levels of eGFR (eGFR < 30 mL/min/1.73 m2, hazard ratio [HR]: 1.38, 95% confidence interval [CI]: 0.99-1.92). Similarly across ACR levels, the risk of stroke was 2-fold higher except for high levels of albuminuria (ACR > 30 mg/g, HR: 1.61, 95% CI: 1.31-1.99). The adjusted risk of stroke with AF differed by combinations of ACR and eGFR categories (interaction P value = .04) compared with those without AF. Both stroke types were more common in patients with AF, and ischemic stroke rates differed significantly by eGFR and ACR categories. Limitations: Medication information was not included. Conclusions: Patients with CKD and AF are at a high risk of total, ischemic, and hemorrhagic strokes; the risk is highest with lower eGFR and higher ACR and differs based on eGFR and the degree of ACR

Fingerprints in Compressed Strings

The Karp-Rabin fingerprint of a string is a type of hash value that due to its strong properties has been used in many string algorithms. In this paper we show how to construct a data structure for a string S of size N compressed by a context-free grammar of size n that answers fingerprint queries. That is, given indices i and j, the answer to a query is the fingerprint of the substring S[i,j]. We present the first O(n) space data structures that answer fingerprint queries without decompressing any characters. For Straight Line Programs (SLP) we get O(logN) query time, and for Linear SLPs (an SLP derivative that captures LZ78 compression and its variations) we get O(log log N) query time. Hence, our data structures has the same time and space complexity as for random access in SLPs. We utilize the fingerprint data structures to solve the longest common extension problem in query time O(log N log l) and O(log l log log l + log log N) for SLPs and Linear SLPs, respectively. Here, l denotes the length of the LCE

Community detection in graphs

The modern science of networks has brought significant advances to our understanding of complex systems. One of the most relevant features of graphs representing real systems is community structure, or clustering, i. e. the organization of vertices in clusters, with many edges joining vertices of the same cluster and comparatively few edges joining vertices of different clusters. Such clusters, or communities, can be considered as fairly independent compartments of a graph, playing a similar role like, e. g., the tissues or the organs in the human body. Detecting communities is of great importance in sociology, biology and computer science, disciplines where systems are often represented as graphs. This problem is very hard and not yet satisfactorily solved, despite the huge effort of a large interdisciplinary community of scientists working on it over the past few years. We will attempt a thorough exposition of the topic, from the definition of the main elements of the problem, to the presentation of most methods developed, with a special focus on techniques designed by statistical physicists, from the discussion of crucial issues like the significance of clustering and how methods should be tested and compared against each other, to the description of applications to real networks.Comment: Review article. 103 pages, 42 figures, 2 tables. Two sections expanded + minor modifications. Three figures + one table + references added. Final version published in Physics Report

Cellular and molecular mechanisms of immunomodulation in the brain through environmental enrichment

Recent studies on environmental enrichment (EE) have shown cytokines, cellular immune components [e.g., T lymphocytes, natural killer (NK) cells], and glial cells in causal relationship to EE in bringing out changes to neurobiology and behavior. The purpose of this review is to evaluate these neuroimmune mechanisms associated with neurobiological and behavioral changes in response to different EE methods. We systematically reviewed common research databases. After applying all inclusion and exclusion criteria, 328 articles remained for this review. Physical exercise (PE), a form of EE, elicits anti-inflammatory and neuromodulatory effects through interaction with several immune pathways including interleukin (IL)-6 secretion from muscle fibers, reduced expression of Toll-like receptors on monocytes and macrophages, reduced secretion of adipokines, modulation of hippocampal T cells, priming of microglia, and upregulation of mitogen-activated protein kinase phosphatase-1 in central nervous system. In contrast, immunomodulatory roles of other enrichment methods are not studied extensively. Nonetheless, studies showing reduction in the expression of IL-1β and tumor necrosis factor-α in response to enrichment with novel objects and accessories suggest anti-inflammatory effects of novel environment. Likewise, social enrichment, though considered a necessity for healthy behavior, results in immunosuppression in socially defeated animals. This has been attributed to reduction in T lymphocytes, NK cells and IL-10 in subordinate animals. EE through sensory stimuli has been investigated to a lesser extent and the effect on immune factors has not been evaluated yet. Discovery of this multidimensional relationship between immune system, brain functioning, and EE has paved a way toward formulating environ-immuno therapies for treating psychiatric illnesses with minimal use of pharmacotherapy. While the immunomodulatory role of PE has been evaluated extensively, more research is required to investigate neuroimmune changes associated with other enrichment methods.Gaurav Singhal, Emily J. Jaehne, Frances Corrigan and Bernhard T. Baun

Association Between Early Follow-up with a Nephrologist and Death in Survivors of Acute Kidney Injury

Background: Survivors of severe acute kidney injury remain at high risk of death well-after apparent recovery from the initial event. Methods: We conducted a cohort study of hospitalized adults in Ontario from 1996 to 2008 with acute kidney injury who received temporary dialysis and survived for 90 days following discharge independent from dialysis. The exposure was nephrology follow-up. We used propensity scores to match individuals with early nephrology follow-up to those without. The primary outcome was time to mortality. Results : We identified 3877 patients with acute kidney injury who met the eligibility criteria. A total of 1583 patients had nephrology follow. The incidence of all-cause mortality was lower in those with early nephrology follow-up as compared to those without early follow-up (8.4 vs. 10.6 per 100 person-years, HR 0.76 (95% CI 0.62-0.93)). Conclusions: Nephrology follow-up after hospitalization with acute kidney injury and temporary dialysis was associated with improved survival.MAS