Increasing the reliability of fully automated surveillance for central line–associated bloodstream infections

OBJECTIVETo increase reliability of the algorithm used in our fully automated electronic surveillance system by adding rules to better identify bloodstream infections secondary to other hospital-acquired infections.METHODSIntensive care unit (ICU) patients with positive blood cultures were reviewed. Central line–associated bloodstream infection (CLABSI) determinations were based on 2 sources: routine surveillance by infection preventionists, and fully automated surveillance. Discrepancies between the 2 sources were evaluated to determine root causes. Secondary infection sites were identified in most discrepant cases. New rules to identify secondary sites were added to the algorithm and applied to this ICU population and a non-ICU population. Sensitivity, specificity, predictive values, and kappa were calculated for the new models.RESULTSOf 643 positive ICU blood cultures reviewed, 68 (10.6%) were identified as central line–associated bloodstream infections by fully automated electronic surveillance, whereas 38 (5.9%) were confirmed by routine surveillance. New rules were tested to identify organisms as central line–associated bloodstream infections if they did not meet one, or a combination of, the following: (I) matching organisms (by genus and species) cultured from any other site; (II) any organisms cultured from sterile site; (III) any organisms cultured from skin/wound; (IV) any organisms cultured from respiratory tract. The best-fit model included new rules I and II when applied to positive blood cultures in an ICU population. However, they didn’t improve performance of the algorithm when applied to positive blood cultures in a non-ICU population.CONCLUSIONElectronic surveillance system algorithms may need adjustment for specific populations.Infect. Control Hosp. Epidemiol. 2015;36(12):1396–1400</jats:sec

Challenges in optics for Extremely Large Telescope instrumentation

We describe and summarize the optical challenges for future instrumentation for Extremely Large Telescopes (ELTs). Knowing the complex instrumental requirements is crucial for the successful design of 30-60m aperture telescopes. After all, the success of ELTs will heavily rely on its instrumentation and this, in turn, will depend on the ability to produce large and ultra-precise optical components like light-weight mirrors, aspheric lenses, segmented filters, and large gratings. New materials and manufacturing processes are currently under study, both at research institutes and in industry. In the present paper, we report on its progress with particular emphasize on volume-phase-holographic gratings, photochromic materials, sintered silicon-carbide mirrors, ion-beam figuring, ultra-precision surfaces, and free-form optics. All are promising technologies opening new degrees of freedom to optical designers. New optronic-mechanical systems will enable efficient use of the very large focal planes. We also provide exploratory descriptions of "old" and "new" optical technologies together with suggestions to instrument designers to overcome some of the challenges placed by ELT instrumentation.Comment: (Proc. OPTICON Key Technology Network Workshop, Rome 20-21 October 2005

Immunologic and vascular biomarkers of mortality in critical COVID-19 in a South African cohort

Introduction: Biomarkers predicting mortality among critical Coronavirus disease 2019 (COVID-19) patients provide insight into the underlying pathophysiology of fatal disease and assist with triaging of cases in overburdened settings. However, data describing these biomarkers in Sub-Saharan African populations are sparse. Methods: We collected serum samples and corresponding clinical data from 87 patients with critical COVID-19 on day 1 of admission to the intensive care unit (ICU) of a tertiary hospital in Cape Town, South Africa, during the second wave of the COVID-19 pandemic. A second sample from the same patients was collected on day 7 of ICU admission. Patients were followed up until in-hospital death or hospital discharge. A custom-designed 52 biomarker panel was performed on the Luminex® platform. Data were analyzed for any association between biomarkers and mortality based on pre-determined functional groups, and individual analytes. Results: Of 87 patients, 55 (63.2%) died and 32 (36.8%) survived. We found a dysregulated cytokine response in patients who died, with elevated levels of type-1 and type-2 cytokines, chemokines, and acute phase reactants, as well as reduced levels of regulatory T cell cytokines. Interleukin (IL)-15 and IL-18 were elevated in those who died, and levels reduced over time in those who survived. Procalcitonin (PCT), C-reactive protein, Endothelin-1 and vascular cell adhesion molecule-1 were elevated in those who died. Discussion: These results show the pattern of dysregulation in critical COVID-19 in a Sub-Saharan African cohort. They suggest that fatal COVID-19 involved excessive activation of cytotoxic cells and the NLRP3 (nucleotide-binding domain, leucine-rich–containing family, pyrin domain–containing-3) inflammasome. Furthermore, superinfection and endothelial dysfunction with thrombosis might have contributed to mortality. HIV infection did not affect the outcome. A clinically relevant biosignature including PCT, pH and lymphocyte percentage on differential count, had an 84.8% sensitivity for mortality, and outperformed the Luminex-derived biosignature

Identification of IKr Kinetics and Drug Binding in Native Myocytes

Determining the effect of a compound on IKr is a standard screen for drug safety. Often the effect is described using a single IC50 value, which is unable to capture complex effects of a drug. Using verapamil as an example, we present a method for using recordings from native myocytes at several drug doses along with qualitative features of IKr from published studies of HERG current to estimate parameters in a mathematical model of the drug effect on IKr. IKr was recorded from canine left ventricular myocytes using ruptured patch techniques. A voltage command protocol was used to record tail currents at voltages from −70 to −20 mV, following activating pulses over a wide range of voltages and pulse durations. Model equations were taken from a published IKr Markov model and the drug was modeled as binding to the open state. Parameters were estimated using a combined global and local optimization algorithm based on collected data with two additional constraints on IKrI–V relation and IKr inactivation. The method produced models that quantitatively reproduce both the control IKr kinetics and dose dependent changes in the current. In addition, the model exhibited use and rate dependence. The results suggest that: (1) the technique proposed here has the practical potential to develop data-driven models that quantitatively reproduce channel behavior in native myocytes; (2) the method can capture important drug effects that cannot be reproduced by the IC50 method. Although the method was developed for IKr, the same strategy can be applied to other ion channels, once appropriate channel-specific voltage protocols and qualitative features are identified

As possibilidades investigativas da aprendizagem histórica de jovens estudantes a partir das histórias em quadrinhos

Resumo O objetivo deste estudo é investigar como a verdade histórica e a intersubjetividade organizam a forma como os jovens tomam o conhecimento para si. A investigação é estruturada nas relações entre a cultura jovem, as histórias em quadrinhos e a cultura histórica de uma sociedade (RÜSEN, 2009). Analisam-se possibilidades investigativas existentes na relação entre as histórias em quadrinhos e a aprendizagem histórica de jovens estudantes. Abordam-se os tipos de investigações sobre como as narrativas históricas gráficas entraram na cultura escolar: 1) os quadrinhos ligados ao mercado das histórias em quadrinhos ficcionais com temas históricos; 2) os livros didáticos; 3) as histórias em quadrinhos didáticas na forma de paradidáticos; 4) as histórias em quadrinhos produzidas pelos próprios estudantes; e 5) as narrativas gráficas autobiográficas

Amoebic lung abscesses : a case report

The original publication is available at http://www.samj.org.zaA case of multiple amoebic lung abscesses without indication of direct extension from a subclinical liver abscess, which delayed correct diagnosis, is reported. Severe constitutional symptoms, life-threatening haemoptysis and large pulmonary lesions were the prominent clinical manifestations. The response to metronidazole was dramatic. It is postulated that haematogenous spread was responsible. The rarity of this form of amoebiasis is evident on published reports.Publishers' versio

Ion flux-film structure relationship during magnetron sputtering of WO

In this work, we have investigated the influence of the magnetic field configuration during magnetron sputtering of WO3 in order to establish the ion flux-film structure relationship. An asymmetric bipolar pulsed DC magnetron sputtering (PDMS) was used with two magnetic field configurations: balanced (BM) and unbalanced (UMB) magnetic configurations. Ion Energy Distribution Functions (IEDFs) of the main ion populations (Ar+, O+) were recorded. The IEDFs are broad with, in addition of the thermalized distribution around 2 eV, two peaks with available ion kinetic energy up to 40–100 eV associated with the positive part of the pulse. Comparing the BM and UBM data, we calculated an increase by a factor of 5 of the ionic current while the average energy per ion was kept constant (~44 eV). X-ray diffraction demonstrates the influence of the magnetic configuration on the coating phase constitution. The films are crystallized in the WO3 monoclinic phase with preferential orientations along the c axis using the BM configuration and along the a axis using the UBM one’s. On the other hand, it has been demonstrated that the grain size increases with the thickness using the BM configuration (up to 18 nm) while it remains constant using the UBM one’s (~7 nm)

Blockade of HERG channels by the class III antiarrhythmic azimilide: mode of action

1. The class III antiarrhythmic azimilide has previously been shown to inhibit I(Ks) and I(Kr) in guinea-pig cardiac myocytes and I(Ks) (minK) channels expressed in Xenopus oocytes. Because HERG channels underly the conductance I(Kr) in human heart, the effects of azimilide on HERG channels expressed in Xenopus oocytes were the focus of the present study. 2. In contrast to other well characterized HERG channel blockers, azimilide blockade was reverse use-dependent, i.e., the relative block and apparent affinity of azimilide decreased with an increase in channel activation frequency. Azimilide blocked HERG channels at 0.1 and 1 Hz with IC(50) s of 1.4 μM and 5.2  μM respectively. 3. In an envelope of tail test, HERG channel blockade increased with increasing channel activation, indicating binding of azimilide to open channels. 4. Azimilide blockade of HERG channels expressed in Xenopus oocytes and I(Kr) in mouse AT-1 cells was decreased under conditions of high [K(+)](e), whereas block of slowly activating I(Ks) channels was not affected by changes in [K(+)](e). 5. In summary, azimilide is a blocker of cardiac delayed rectifier channels, I(Ks) and HERG. Because of the distinct effects of stimulation frequency and [K(+)](e) on azimilide block of I(Kr) and I(Ks) channels, we conclude that the relative contribution of block of each of these cardiac delayed rectifier channels depends on heart frequency. [K(+)](e) and regulatory status of the respective channels

Western Star, 1911-04-05

The Western Star began publication on Newfoundland's west coast on 4 April 1900, appearing weekly with brief semiweekly periods up to 1952, when it became a daily. As of 17 April 2019 it continues as a free weekly community paper