294 research outputs found
The origin of green icebergs in Antarctica
A comparison of samples from a translucent green iceberg with a core from the Ronne Ice Shelf revealed an excellent agreement in isotopic composition, crystal structure, and incorporated sediment particles. Marine shelf ice which constitutes the basal portion of some ice shelves is considered to be the source of green icebergs. It most likely results from "ice pump" processes which produce large amounts of ice platelets in the water column beneath ice shelves. These subsequently accumulate and become compacted into bubble-free, desalinated ice. Iceberg and drift-buoy trajectories indicate that green icebergs observed in the Weddell Sea originate from the Amery Ice Shelf rather than from the Ronne Ice Shelf, although the latter ice shelf is also a potential source
Gelchromatographie, eine Methode zur Stofftrennung aufgrund von Molekulargewichtsunterschieden
A Smart Wireless Car Ignition System for Vehicle Security
Copyright: © 2017 Haider A, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.The paper proposes a novel car ignition system to replace the traditional wired technology and enhance vehicle security. This new system uses wireless transmissions to start the engine and hence eliminates the ignition wire behind the dashboard. It also allows the user to set a password of his/her choice to keep the system protected. A theft alarm that goes ‘’ON’’ when an unusual activity is sensed and/or when the wrong password is attempted to unlock the system is integrated in the system. Moreover, important factors such as economic feasibility, adaptability to the new vehicle technologies and customers’ preferences have been taken into consideration in the design of the proposed vehicle security system.Peer reviewedFinal Published versio
Serumproteinbindung von ACTH
3H- 1–23-Corticotropin wurde an Dextrangel (Sephadex G-25) gebunden und konnte durch Serumproteine, Albumin oder 0,1 N HCl eluiert werden. Mittels Dextrangelfiltration wurde gefunden, daß3H-ACTH kompetitiv an Serumproteine (Albumin) und Dextrangel gebunden wurde. Auch für natürliches Schweine-ACTH und endogenes ACTH in Patientenplasma (Adrenalektomie) wurde mittels biologischer ACTH-Bestimmung die Bindung von ACTH an Proteine bestätigt.3H- 1–23 corticotropin was bound to dextran gel (sephadex G-25) and was eluted by either serum proteins, albumin or 0.1 N HCl. Competitive binding of3H-ACTH to serum proteins (albumin) and dextran gel was shown by dextran gel filtration. Likewise natural ACTH (pig) and endogenous ACTH from plasma of an adrenalectomized patient were shown to be partly protein bound using biological ACTH-assay
Enteral Vancomycin to Eliminate MRSA Carriership of the Digestive Tract in Critically Ill Patients
Background: Carriership with methicillin resistant Staphylococcus aureus (MRSA) is a risk for the development of secondary infections in critically ill patients. Previous studies suggest that enteral vancomycin is able to eliminate enteral carriership with MRSA. Data on individual effects of this treatment are lacking. Methods: Retrospective analysis of a database containing 15 year data of consecutive patients from a mixed medical-(cardio)surgical 18 bedded intensive care unit was conducted. All consecutive critically ill patients with enteral MRSA carriership detected in throat and/or rectal samples were collected. We analyzed those with follow-up cultures to determine the success rate of enteral vancomycin. Topical application of 2% vancomycin in a sticky oral paste was performed combined with a vancomycin solution of 500 mg four times daily in the nasogastric tube. This treatment was added to a regimen of selective digestive tract decontamination (SDD) to prevent ICU acquired infection. Results: Thirteen patients were included. The mean age was 65 years and the median APACHE II score was 21. MRSA was present in the throat in 8 patients and in both throat and rectum in 5 patients. In all patients MRSA was successfully eliminated from both throat and rectum, which took 2–11 days with a median duration until decontamination of 4 days. Secondary infections with MRSA did not occur. Conclusions: Topical treatment with vancomycin in a 2% sticky oral paste four times daily in the nasogastric tube was effective in all patients in the elimination of MRSA and prevented secondary MRSA infections
Diagnostische Bedeutung der Proteinbindung von Plasmacortisol, bestimmt durch Dextrangelfiltration
1. Mittels Dextrangelfiltration wurde nach Inkubation von markiertem Cortisol und Plasma der proteingebundene und der sog. freie Anteil (%) des endogenen Plasmacortisols ermittelt und bei gleichzeitiger fluorimetrischer Bestimmung der 11-OHCS auch die Menge proteingebundenen, bzw. sog. freien Cortisols (µg-%) berechnet.
2. Die diagnostische Brauchbarkeit der Methode wurde bei Patienten mit Nebennierenrindeninsuffizienz, mit Hypophysentumoren, nach Hypophysektomie, mit Cushing-Syndrom mit der fluorimetrischen Bestimmung der 11-OHCS verglichen. Die einfache Bestimmung der Cortisolbindung war bei hypophysektomierten Patienten der Bestimmung der 11-OHCS überlegen und entsprach der aufwendigeren ACTH-Belastung.
3. Falsch hohe fluorimetrische 11-OHCS-Spiegel im Plasma unter Spirolacton- oder Oestrogenbehandlung und in der Gravidität lassen sich durch Bestimmung der Cortisolbindung klären. Bei Schilddrüsenüberfunktion war das sog. freie Cortisol im Plasma relativ und absolut vermehrt, bei Schilddrüsenunterfunktion fand sich eine Zunahme des plasmaproteingebundenen Cortisols.1. Following incubation of labeled cortisol and plasma the percentages of protein bound and socalled free endogenous cortisol were determined by means of dextran gel filtration.
2. The diagnostic value of this method was compared with fluorimetric determinations of 11-OHCS for patients with adrenal insufficiency, Cushing-Syndrome, pituitary tumors and after hypophysectomy. In hypophysectomized patients the simple determination of protein bound cortisol was found to correlate well with diagnostic ACTH-infusion tests and to be more sensitive than fluorimetric determinations of 11-OHCS in 9 a.m. plasma.
3. Falsely elevated fluorimetric values of plasma 11-OHCS in patients treated with spirolactone or estrogens, resp. during pregnancy may be recognized through determination of cortisol binding. — In thyrotoxicosis socalled free cortisol was elevated, both relatively and absolutely; in hypothyroidism an increase of protein bound cortisol was found
Evaluating Comprehensibility of 157 Patient-Reported Outcome Measures (PROMs) in the Nationwide Dutch Outcome-Based Healthcare Program:More Attention for Comprehensibility of PROMs is Needed
IntroductionPatient-reported outcomes measures (PROMs) are increasingly prevalent in healthcare and used for shared decision-making and healthcare quality evaluation. However, the extent to which patients with varying health literacy levels can complete PROMs is often overlooked. This may lead to biased aggregated data and patients being excluded from studies or other PROM collection initiatives. This cross-sectional study evaluates the comprehensibility of 157 well-known and widely used PROM scales using a comprehensibility checklist.MethodsPairs of two independent raters scored 157 PROM scales designed for adults included in the 35 sets of outcome information developed as part of the Dutch Outcome-Based Healthcare Program. The PROM scales were scored on the eight comprehensibility domains of the Pharos Checklist for Questionnaires in Healthcare (PCQH). Interrater agreement of domain ratings was assessed using Intraclass Correlation Coefficients or Cohen's kappa. Subsequently, final ratings were established through discussion and used to evaluate the domain-specific comprehensibility rating for each PROM scale.ResultsComprehensibility of a large number of PROM scales (n = 157), which cover a wide range of diseases and conditions across Dutch medical specialist care, was assessed. While most PROM scales were written at an accessible language level, with minimal use of medical terms, instruction clarity, number of questions, and response options emerged as significant issues, affecting a substantial proportion of PROM scales. Interrater agreement was high for most domains of the PCQH.ConclusionThis study highlights the need for greater attention to the comprehensibility of PROMs to ensure their accessibility to all patients, including those with low health literacy. The PCQH can be a valuable tool in PROM development in addition to qualitative methods and in selection processes enabling comparison of comprehensibility between PROMs. However, the PCQH needs further development and validation for these purposes. Enhancing the comprehensibility of PROMs is essential for their effective incorporation in healthcare evaluation and decision-making processes
Plasma CC16 levels are associated with development of ALI/ARDS in patients with ventilator-associated pneumonia: a retrospective observational study
<p>Abstract</p> <p>Background</p> <p>Despite consensus criteria, diagnosing acute lung injury, or its more severe form acute respiratory distress syndrome (ALI/ARDS) remains challenging. Adding objective measures, such as plasma levels of biological markers could facilitate recognition of ALI/ARDS. This study was designed to assess and compare the diagnostic accuracy of biological markers for ALI/ARDS with ventilator-associated pneumonia (VAP).</p> <p>Methods</p> <p>We performed serial measurements of Clara cell protein (CC16), soluble receptor for advanced glycation end products (sRAGE), surfactant protein D (SP-D) and Krebs von den Lungen (KL-6) in plasma of patients with VAP and mechanically ventilated control patients without VAP. ALI/ARDS was diagnosed using the criteria of the North-American European consensus conference.</p> <p>Results</p> <p>Thirty-seven patients were enrolled - 22 patients with VAP and 15 control patients. Ten patients with pneumonia met the ALI/ARDS consensus criteria. Control patients never met these criteria. Plasma CC16 had a good diagnostic capacity for ALI/ARDS as shown by the receiver operating characteristic curve with an area under the curve of 0.91 (95% confidence interval (CI) 0.79 - 1.00; <it>p </it>< 0.001). Identification of ALI/ARDS patients by sudden increases in plasma CC16 of 30% or more yielded a sensitivity of 90% and a specificity of 92%. Of note, levels of CC16 increased 2 days before ALI/ARDS diagnosis. A cut-off level of 50 ng/ml SP-D yielded a specificity of 100% while the sensitivity was 70%. The area under the curve for SP-D was 0.80 (95% CI 0.58 - 1.00; <it>p </it>= 0.02). The diagnostic accuracies of KL-6 and sRAGE were low.</p> <p>Conclusion</p> <p>Plasma CC16 seems a potential biological marker for ALI/ARDS in patients with VAP. Plasma levels of sRAGE, SP-D and KL-6 have limited discriminative power for diagnosing ALI/ARDS in VAP.</p
Ki-67 as a prognostic marker in mantle cell lymphoma—consensus guidelines of the pathology panel of the European MCL Network
Mantle cell lymphoma (MCL) has a heterogeneous clinical course and is mainly an aggressive B cell non-Hodgkin lymphoma; however, there are some indolent cases The Ki-67 index, defined by the percentage of Ki-67-positive lymphoma cells on histopathological slides, has been shown to be a very powerful prognostic biomarker. The pathology panel of the European MCL Network evaluated methods to assess the Ki-67 index including stringent counting, digital image analysis, and estimation by eyeballing. Counting of 2 × 500 lymphoma cells is the gold standard to assess the Ki-67 index since this value has been shown to predict survival in prospective randomized trials of the European MCL Network. Estimation by eyeballing and digital image analysis showed a poor concordance with the gold standard (concordance correlation coefficients [CCC] between 0.29 and 0.61 for eyeballing and CCC of 0.24 and 0.37 for two methods of digital image analysis, respectively). Counting a reduced number of lymphoma cells (2 × 100 cells) showed high interobserver agreement (CCC = 0.74). Pitfalls of the Ki-67 index are discussed and guidelines and recommendations for assessing the Ki-67 index in MCL are given
RELAx - REstricted versus Liberal positive end-expiratory pressure in patients without ARDS: protocol for a randomized controlled trial
Background Evidence for benefit of high positive end-expiratory pressure (PEEP) is largely lacking for invasively ventilated, critically ill patients with uninjured lungs. We hypothesize that ventilation with low PEEP is noninferior to ventilation with high PEEP with regard to the number of ventilator-free days and being alive at day 28 in this population. Methods/Design The “REstricted versus Liberal positive end-expiratory pressure in patients without ARDS” trial (RELAx) is a national, multicenter, randomized controlled, noninferiority trial in adult intensive care unit (ICU) patients with uninjured lungs who are expected not to be extubated within 24 h. RELAx will run in 13 ICUs in the Netherlands to enroll 980 patients under invasive ventilation. In all patients, low tidal volumes are used. Patients assigned to ventilation with low PEEP will receive the lowest possible PEEP between 0 and 5 cm H2O, while patients assigned to ventilation with high PEEP will receive PEEP of 8 cm H2O. The primary endpoint is the number of ventilator-free days and being alive at day 28, a composite endpoint for liberation from the ventilator and mortality until day 28, with a noninferiority margin for a difference between groups of 0.5 days. Secondary endpoints are length of stay (LOS), mortality, and occurrence of pulmonary complications, including severe hypoxemia, major atelectasis, need for rescue therapies, pneumonia, pneumothorax, and development of acute respiratory distress syndrome (ARDS). Hemodynamic support and sedation needs will be collected and compared. Discussion RELAx will be the first sufficiently sized randomized controlled trial in invasively ventilated, critically ill patients with uninjured lungs using a clinically relevant and objective endpoint to determine whether invasive, low-tidal-volume ventilation with low PEEP is noninferior to ventilation with high PEEP
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