Acute-Phase-HDL Remodeling by Heparan Sulfate Generates a Novel Lipoprotein with Exceptional Cholesterol Efflux Activity from Macrophages

During episodes of acute-inflammation high-density lipoproteins (HDL), the carrier of so-called good cholesterol, experiences a major change in apolipoprotein composition and becomes acute-phase HDL (AP-HDL). This altered, but physiologically important, HDL has an increased binding affinity for macrophages that is dependent on cell surface heparan sulfate (HS). While exploring the properties of AP-HDL∶HS interactions we discovered that HS caused significant remodeling of AP-HDL. The physical nature of this change in structure and its potential importance for cholesterol efflux from cholesterol-loaded macrophages was therefore investigated. In the presence of heparin, or HS, AP-HDL solutions at pH 5.2 became turbid within minutes. Analysis by centrifugation and gel electrophoresis indicated that AP-HDL was remodeled generating novel lipid poor particles composed only of apolipoprotein AI, which we designate β2. This remodeling is dependent on pH, glycosaminoglycan type, is promoted by Ca2+ and is independent of protease or lipase activity. Compared to HDL and AP-HDL, remodeled AP-HDL (S-HDL-SAA), containing β2 particles, demonstrated a 3-fold greater cholesterol efflux activity from cholesterol-loaded macrophage. Because the identified conditions causing this change in AP-HDL structure and function can exist physiologically at the surface of the macrophage, or in its endosomes, we postulate that AP-HDL contains latent functionalities that become apparent and active when it associates with macrophage cell surface/endosomal HS. In this way initial steps in the reverse cholesterol transport pathway are focused at sites of injury to mobilize cholesterol from macrophages that are actively participating in the phagocytosis of damaged membranes rich in cholesterol. The mechanism may also be of relevance to aspects of atherogenesis

Hyper-compressions: The rise of flash fiction in “post-transitional” South Africa

Blair, P. (2020). Hyper-compressions: The rise of flash fiction in “post-transitional” South Africa', The Journal of Commonwealth Literature, 55(1), 38-60. Copyright © 2018. Reprinted by permission of SAGE Publications.This article begins with a survey of flash fiction in “post-transitional” South Africa, which it relates to the nation’s post-apartheid canon of short stories and short-short stories, to the international rise of flash fiction and “sudden fiction”, and to the historical particularities of South Africa’s “post-transition”. It then undertakes close readings of three flash fictions republished in the article, each less than 450 words: Tony Eprile’s “The interpreter for the tribunal” (2007), which evokes the psychological and ethical complexities, and long-term ramifications, of the Truth and Reconciliation Commission; Michael Cawood Green’s “Music for a new society” (2008), a carjacking story that invokes discourses about violent crime and the “‘new’ South Africa”; and Stacy Hardy’s “Kisula” (2015), which maps the psychogeography of cross-racial sex and transnational identity-formation in an evolving urban environment. The article argues that these exemplary flashes are “hyper-compressions”, in that they compress and develop complex themes with a long literary history and a wide contemporary currency. It therefore contends that flash fiction of South Africa’s post-transition should be recognized as having literary-historical significance, not just as an inherently metonymic form that reflects, and alludes to, a broader literary culture, but as a genre in its own right

Risk Prediction for Acute Kidney Injury in Acute Medical Admissions in the UK

Background Acute Kidney Injury (AKI) is associated with adverse outcomes; identifying patients who are at risk of developing AKI in hospital may lead to targeted prevention. This approach is advocated in national guidelines but is not well studied in acutely unwell medical patients. We therefore aimed to undertake a UK-wide study in acute medical units (AMUs) with the following aims: to define the proportion of acutely unwell medical patients who develop hospital-acquired AKI (hAKI); to determine risk factors associated with the development of hAKI; and to assess the feasibility of using these risk factors to develop an AKI risk prediction score. Methods In September 2016, a prospective multicentre cohort study across 72 UK AMUs was undertaken. Data were collected from all patients who presented over a 24-hour period. Chronic dialysis, community-acquired AKI (cAKI) and those with fewer than two creatinine measurements were subsequently excluded. The primary outcome was the development of h-AKI. Results 2,446 individuals were admitted to the AMUs of the 72 participating centres. 384 patients (16%) sustained AKI of whom 287 (75%) were cAKI and 97 (25%) were hAKI. After exclusions, 1,235 participants remained in whom chronic kidney disease (OR 3.08, 95% CI 1.96-4.83), diuretic prescription (OR 2.33, 95% CI 1.5-3.65), a lower haemoglobin concentration and an elevated serum bilirubin were independently associated with development of hAKI. Multivariable model discrimination was moderate (c-statistic 0.75), and this did not support the development of a robust clinical risk prediction score. Mortality was higher in those with hAKI (adjusted OR 5.22; 95% CI 2.23-12.20). Conclusion AKI in AMUs is common and associated with worse outcomes, with the majority of cases community acquired. The smaller proportion of hAKI cases, only moderate discrimination of prognostic risk factor modelling and the resource implications of widespread application of an AKI clinical risk score across all AMU admissions suggests that this approach is not currently justified. More targeted risk assessment or automated methods of calculating individual risk may be more appropriate alternatives

Love, love, love me.

" from the comic cartoons of George P. McManus" [note]Gift of Dr. Mary Jane Esplen.Piano vocal [instrumentation]C major [key]Popular song [form/genre]Man, rope, hands, cliff [illustration]Publisher's advertisement on back cover [note

Fast encoding of synthetic aperture radar raw data using compressed sensing

Synthetic Aperture Radar (SAR) is active and coherent microwave high resolution imaging system, which has the capability to image in all weather and day-night conditions. SAR transmits chirp signals and the received echoes are sampled into In-phase (I) and Quadrature (Q) components, generally referred to as raw SAR data. The various modes of SAR coupled with the high resolution and wide swath requirements result in a huge amount of data, which will easily exceed the on-board storage and downlink bandwidth of a satellite. This paper addresses the compression of the raw SAR data by sampling the signal below Nyquist rate using ideas from Compressed Sensing (CS). Due to the low computational resources available onboard satellite, the idea is to use a simple encoder, with a 2D FFT and a random sampler. Decoding is then based on convex optimization or uses greedy algorithms such as Orthogonal Matching Pursuit (OMP

Otimização conjunta de gráficos de X-barra - S ou X-barra - R: um procedimento de fácil implementação Joint optimization of X-bar - S or X-bar - R charts: an easily implemented procedure

Este trabalho desenvolve um modelo para escolha ótima dos parâmetros de operação de gráficos de X-barra e R (ou de X-barra e S) que minimiza a razão entre o custo de amostragem e a rapidez de detecção de desvios na média ou aumentos na dispersão do processo. Admitem-se três formas alternativas para o problema: minimizar os tempos médios de sinalização sob uma restrição ao custo de amostragem; minimizar esse custo sob uma restrição aos tempos de sinalização; e o problema multiobjetivo de minimizar o custo e os tempos de sinalização. Restrições adicionais são permitidas, para tratar de variantes do problema encontráveis na prática. O procedimento evita a complexidade dos modelos de projeto econômico usuais. São detalhados métodos para determinação dos poucos parâmetros de especificação e entrada exigidos pelo modelo. Um exemplo mostra que o procedimento é de fácil aplicação. Tudo isto aumenta sua aplicabilidade para um grande espectro de situações práticas típicas.<br>A model is developed for optimum choice of the operation parameters for X-bar - R (or X-bar - S) charts, which minimizes the ratio of sampling costs to detection speed of shifts in the process mean or increases in the process dispersion. Three alternative problem formulations are allowed: minimization of the average time to signal subject to a sampling cost constraint; minimization of the sampling cost subject to a constraint on the average times to signal; and multi-objective optimization of both the average time to signal and the sampling cost. Through optional additional constraints, several practical variants of the problem are admitted. The procedure avoids the complexity of usual economic design models, and methods for determining the values for the few input and specification parameters required are given in detail. An example shows that the procedure is easy to apply. All these features increase its applicability for a wide range of typical practical situations