Drug-induced renal Fanconi syndrome

A number of therapeutic drugs are toxic to the kidney proximal tubule (PT) and can cause the renal Fanconi syndrome (FS). The most frequently implicated drugs are cisplatin, ifosfamide, tenofovir, sodium valproate and aminoglycoside antibiotics, and the new oral iron chelator deferasirox has also recently been associated with FS. The incidence of full or partial FS is almost certainly under-estimated due to a lack of appropriate systematic studies, variations in definitions of tubular dysfunction and under-reporting of adverse events. The clinical features of FS are amino aciduria, low molecular weight proteinuria, hypophosphataemia, metabolic acidosis and glycosuria. The most serious complications are bone demineralization from urinary phosphate wasting and progressive decline in kidney function. Commonly used tests for kidney function such as estimated glomerular filtration rate and urine albumin/creatinine ratio are not sensitive markers of PT toxicity; patients at risk should thus be monitored with more appropriate tests, and drugs should be stopped or reduced in dose if toxicity occurs. Substantial recovery of PT function can occur after withdrawal of therapy, but this can take months and chronic damage may persist in some case

Investigating Follower Felt Trust from a Social Cognitive Perspective

Previous organizational research on trust has focused more on subordinates’ trust in their leaders than on their experience of felt trust from the leader, even though the latter is also an important component of trust relationships. Our paper addresses a recent call for more theoretical explanations of the mechanism through which followers’ felt trust influences their in-role and extra-role performance. Based on social cognitive theory, we proposed that occupational self-efficacy (OSE) mediates the felt trust-performance relationship in workplace settings, and tested these relationships in two empirical studies. Study 1 was a cross-sectional pre-study (N = 189) investigating only the mediating effects of OSE. For the main study, i.e., Study 2 (N = 500), we collected data at three different measurement occasions to minimize response bias. Study 2 investigated the mediation of the felt trust-performance relationship not only by OSE, but also by an additional mediator variable (organization-based self-esteem) that had been identified in previous studies, in order to determine whether the OSE effects remained significant. In both studies, structural equation modelling results supported the proposed mediating effects of OSE on the three performance outcomes for the reliance component of felt trust, but not for the disclosure component of felt trust

Complex systems modelling for statistical forecasting of winter North Atlantic atmospheric variability: a new approach

Seasonal forecasts of winter North Atlantic atmospheric variability have until recently shown little skill. Here we present a new technique for developing both linear and non‐linear statistical forecasts of the winter North Atlantic Oscillation (NAO) based on complex systems modelling, which has been widely used in a range of fields, but generally not in climate research. Our polynomial NARMAX models demonstrate considerable skill in out‐of‐sample forecasts and their performance is superior to that of linear models, albeit with small sample sizes. Predictors can be readily identified and this has the potential to inform the next generation of dynamical models and models allow for the incorporation of non‐linearities in interactions between predictors and atmospheric variability. In general there is more skill in forecasts developed over a shorter training period from 1980 compared with an equivalent forecast using training data from 1956. This latter point may relate to decreased inherent predictability in the period 1955‐1980, a wider range of available predictors since 1980 and/or reduced data quality in the earlier period and is consistent with previously identified decadal variability of the NAO. A number of predictors such as sea‐level pressure over the Barents Sea, and a clear tropical signal are commonly selected by both linear and polynomial NARMAX models. Tropical signals are modulated by higher latitude boundary conditions. Both approaches can be extended to developing probabilistic forecasts and to other seasons and indices of atmospheric variability such as the East Atlantic pattern and jet stream metrics

Screening for Atrial Fibrillation and the Role of Digital Health Technologies

Atrial fibrillation is the commonest clinical arrhythmia and a leading cause of hospital admission, morbidity and mortality. New digital health technologies are now allowing patients and the general population to identify heart rhythm abnormalities before any encounter with a medical professional. This chapter will include an overview of the prevalence of atrial fibrillation and explore the current recommendations on methods for arrhythmia screening. We discuss different risk factors as well as physiological and structural markers for atrial fibrillation onset. We explore in detail the application of novel digital health technologies such as wearables, watches and mobile devices which may have an impact on screening detection rates. The article concludes with a discussion about how to manage patients with screen detected atrial fibrillation

Use of cumulative mortality data in patients with acute myocardial infarction for early detection of variation in clinical practice: observational study

OBJECTIVES: Use of cumulative mortality adjusted for case mix in patients with acute myocardial infarction for early detection of variation in clinical practice. DESIGN: Observational study. SETTING: 20 hospitals across the former Yorkshire region. PARTICIPANTS: All 2153 consecutive patients with confirmed acute myocardial infarction identified during three months. MAIN OUTCOME MEASURES: Variable life­adjusted displays showing cumulative differences between observed and expected mortality of patients; expected mortality calculated from risk model based on admission characteristics of age, heart rate, and systolic blood pressure. RESULTS: The performance of two individual hospitals over three months was examined as an example. One, the smallest district hospital in the region, had a series of 30 consecutive patients but had five more deaths than predicted. The variable life­adjusted display showed minimal variation from that predicted for the first 15 patients followed by a run of unexpectedly high mortality. The second example was the main tertiary referral centre for the region, which admitted 188 consecutive patients. The display showed a period of apparently poor performance followed by substantial improvement, where the plot rose steadily from a cumulative net lives saved of - 4 to 7. These variations in patient outcome are unlikely to have been revealed during conventional audit practice. CONCLUSIONS: Variable life­adjusted display has been integrated into surgical care as a graphical display of risk­adjusted survival for individual surgeons or centres. In combination with a simple risk model, it may have a role in monitoring performance and outcome in patients with acute myocardial infarction

“Facing” leaders: Facial expression and leadership perception

This experimental study investigated the effect of a leader's expression of happy versus nervous emotions on subsequent perceptions of leadership and ratings of traits associated with implicit leadership theories (ILTs). Being fast and universally understood, emotions are ideal stimuli for investigating the dynamic effects of ILTs, which were understood in this study in terms of the constraints that expressed emotions impose on the connectionist networks that activate ILTs. The experimental design contrasted videotaped and still frame presentations of a leadership event; however, this methodological factor had no significant effects and analyses were thus collapsed across this factor. Key findings were that the expression of a happy versus nervous emotion at the end of a problem-solving sequence had multiple effects: happy emotions resulted in higher leadership ratings, higher trait ratings, greater correlations among trait ratings, and greater dependence of trait ratings on leadership perceptions. An exploratory model suggested that leadership impressions mediated the effects of facial emotions on trait ratings. The discussion further links the study findings with interpretations in terms of ILTs and many types of constraints on these cognitive structures. It also suggests ways to integrate these ideas with advances in neuroscience research

Effects of Anaesthesia with a High Oxygen Concentration on the Acid-Base State of Babies Delivered at Elective Caesarean Section

Babies delivered from mothers who had 60% oxygen administered during general anaesthesia at elective Caesarean section, had higher pH and lower pCO2 levels, and were clinically in better condition than babies delivered after a similar induction-delivery interval when a concentration of 30 - 33% oxygen was given to the mother. The clinical and acid-base states in both these groups of babies were not as good as in those delivered after induction- delivery times of less than 6 minutes

Simple Statistical Probabilistic Forecasts of the winter NAO

The variability of the North Atlantic Oscillation (NAO) is a key aspect of Northern Hemisphere atmospheric circulation and has a profound impact upon the weather of the surrounding landmasses. Recent success with dynamical forecasts predicting the winter NAO at lead times of a few months has the potential to deliver great socioeconomic impacts. Here, a linear regression model is found to provide skillful predictions of the winter NAO based on a limited number of statistical predictors. Identified predictors include El Niño, Arctic sea ice, Atlantic SSTs, and tropical rainfall. These statistical models can show significant skill when used to make out-of-sample forecasts, and the method is extended to produce probabilistic predictions of the winter NAO. The statistical hindcasts can achieve similar levels of skill to state-of-the-art dynamical forecast models, although out-of-sample predictions are less skillful, albeit over a small period. Forecasts over a longer out-of-sample period suggest there is true skill in the statistical models, comparable with that of dynamical forecasting models. They can be used both to help evaluate and to offer insight into the sources of predictability and limitations of dynamical models

Spreading lengths of Hermite polynomials

The Renyi, Shannon and Fisher spreading lengths of the classical or hypergeometric orthogonal polynomials, which are quantifiers of their distribution all over the orthogonality interval, are defined and investigated. These information-theoretic measures of the associated Rakhmanov probability density, which are direct measures of the polynomial spreading in the sense of having the same units as the variable, share interesting properties: invariance under translations and reflections, linear scaling and vanishing in the limit that the variable tends towards a given definite value. The expressions of the Renyi and Fisher lengths for the Hermite polynomials are computed in terms of the polynomial degree. The combinatorial multivariable Bell polynomials, which are shown to characterize the finite power of an arbitrary polynomial, play a relevant role for the computation of these information-theoretic lengths. Indeed these polynomials allow us to design an error-free computing approach for the entropic moments (weighted L^q-norms) of Hermite polynomials and subsequently for the Renyi and Tsallis entropies, as well as for the Renyi spreading lengths. Sharp bounds for the Shannon length of these polynomials are also given by means of an information-theoretic-based optimization procedure. Moreover, it is computationally proved the existence of a linear correlation between the Shannon length (as well as the second-order Renyi length) and the standard deviation. Finally, the application to the most popular quantum-mechanical prototype system, the harmonic oscillator, is discussed and some relevant asymptotical open issues related to the entropic moments mentioned previously are posed.Comment: 16 pages, 4 figures. Journal of Computational and Applied Mathematics (2009), doi:10.1016/j.cam.2009.09.04