101 research outputs found

    Evaluating privacy-preserving record linkage using cryptographic long-term keys and multibit trees on large medical datasets.

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    Background: Integrating medical data using databases from different sources by record linkage is a powerful technique increasingly used in medical research. Under many jurisdictions, unique personal identifiers needed for linking the records are unavailable. Since sensitive attributes, such as names, have to be used instead, privacy regulations usually demand encrypting these identifiers. The corresponding set of techniques for privacy-preserving record linkage (PPRL) has received widespread attention. One recent method is based on Bloom filters. Due to superior resilience against cryptographic attacks, composite Bloom filters (cryptographic long-term keys, CLKs) are considered best practice for privacy in PPRL. Real-world performance of these techniques using large-scale data is unknown up to now. Methods: Using a large subset of Australian hospital admission data, we tested the performance of an innovative PPRL technique (CLKs using multibit trees) against a gold-standard derived from clear-text probabilistic record linkage. Linkage time and linkage quality (recall, precision and F-measure) were evaluated. Results: Clear text probabilistic linkage resulted in marginally higher precision and recall than CLKs. PPRL required more computing time but 5 million records could still be de-duplicated within one day. However, the PPRL approach required fine tuning of parameters. Conclusions: We argue that increased privacy of PPRL comes with the price of small losses in precision and recall and a large increase in computational burden and setup time. These costs seem to be acceptable in most applied settings, but they have to be considered in the decision to apply PPRL. Further research on the optimal automatic choice of parameters is needed

    Reliability and Initial Validation of the Ulcerative Colitis Endoscopic Index of Severity

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    Background & AimsWe studied the reliability of the previously described Ulcerative Colitis Endoscopic Index of Severity (UCEIS) and validated it with an independent cohort of investigators.MethodsWe created a new library of 57 videos of flexible sigmoidoscopy and stratified them based on disease severity. Twenty-five investigators were each randomly assigned to assess 28 videos (which included 4 duplicates to assess intraobserver reliability). Investigators were blinded to clinical details except for 2 of 4 duplicated videos (to assess the impact of knowledge of symptoms on assessment). Three descriptors (“vascular pattern”, “bleeding”, and “erosions and ulcers”) comprising the UCEIS were scored with a visual analogue scale (VAS) to assess overall severity. Intrainvestigator and interinvestigator agreement was characterized by κ statistical analysis; reliability ratios were used to compare VAS and UCEIS scores.ResultsThere was a high level of correlation between UCEIS scores and overall assessment of severity (correlation coefficient, 0.93). Internal consistency (Cronbach α analysis) was 0.86. Intrainvestigator and interinvestigator reliability ratios for UCEIS scores were 0.96 and 0.88, respectively. Intrainvestigator agreement in determination of the UCEIS score was good (κ = 0.72), with individual descriptors ranging from a κ of 0.47 (for bleeding) to 0.87 (for vascular pattern). Interinvestigator agreement in determination of UCEIS scores was moderate (κ = 0.50), with descriptors ranging from a κ of 0.48 (for bleeding) to 0.54 (for vascular pattern). Intrainvestigator variability in determining UCEIS scores did not change appreciably when a video was presented with clinical details.ConclusionsThe UCEIS and its components show satisfactory intrainvestigator and interinvestigator reliability. Among investigators, the UCEIS accounted for a median of 86% of the variability in evaluation of overall severity on the VAS when assessing the endoscopic severity of UC and was unaffected by knowledge of clinical details

    Palliative care for the elderly - developing a curriculum for nursing and medical students

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    <p>Abstract</p> <p>Background</p> <p>Delivering palliative care to elderly, dying patients is a present and future challenge. In Germany, this has been underlined by a 2009 legislation implementing palliative care as compulsory in the medical curriculum. While the number of elderly patients is increasing in many western countries multimorbidity, dementia and frailty complicate care. Teaching palliative care of the elderly to an interprofessional group of medical and nursing students can help to provide better care as acknowledged by the ministry of health and its expert panels.</p> <p>In this study we researched and created an interdisciplinary curriculum focussing on the palliative care needs of the elderly which will be presented in this paper.</p> <p>Methods</p> <p>In order to identify relevant learning goals and objectives for the curriculum, we proceeded in four subsequent stages.</p> <p>We searched international literature for existing undergraduate palliative care curricula focussing on the palliative care situation of elderly patients; we searched international literature for palliative care needs of the elderly. The searches were sensitive and limited in nature. Mesh terms were used where applicable. We then presented the results to a group of geriatrics and palliative care experts for critical appraisal. Finally, the findings were transformed into a curriculum, focussing on learning goals, using the literature found.</p> <p>Results</p> <p>The literature searches and expert feedback produced a primary body of results. The following deduction domains emerged: Geriatrics, Palliative Care, Communication & Patient Autonomy and Organisation & Social Networks. Based on these domains we developed our curriculum.</p> <p>Conclusions</p> <p>The curriculum was successfully implemented following the Kern approach for medical curricula. The process is documented in this paper. The information given may support curriculum developers in their search for learning goals and objectives.</p

    International criteria for electrocardiographic interpretation in athletes: Consensus statement.

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    Sudden cardiac death (SCD) is the leading cause of mortality in athletes during sport. A variety of mostly hereditary, structural or electrical cardiac disorders are associated with SCD in young athletes, the majority of which can be identified or suggested by abnormalities on a resting 12-lead electrocardiogram (ECG). Whether used for diagnostic or screening purposes, physicians responsible for the cardiovascular care of athletes should be knowledgeable and competent in ECG interpretation in athletes. However, in most countries a shortage of physician expertise limits wider application of the ECG in the care of the athlete. A critical need exists for physician education in modern ECG interpretation that distinguishes normal physiological adaptations in athletes from distinctly abnormal findings suggestive of underlying pathology. Since the original 2010 European Society of Cardiology recommendations for ECG interpretation in athletes, ECG standards have evolved quickly, advanced by a growing body of scientific data and investigations that both examine proposed criteria sets and establish new evidence to guide refinements. On 26-27 February 2015, an international group of experts in sports cardiology, inherited cardiac disease, and sports medicine convened in Seattle, Washington (USA), to update contemporary standards for ECG interpretation in athletes. The objective of the meeting was to define and revise ECG interpretation standards based on new and emerging research and to develop a clear guide to the proper evaluation of ECG abnormalities in athletes. This statement represents an international consensus for ECG interpretation in athletes and provides expert opinion-based recommendations linking specific ECG abnormalities and the secondary evaluation for conditions associated with SCD

    Determinants of Functional Coupling between Astrocytes and Respiratory Neurons in the Pre-Bötzinger Complex

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    Respiratory neuronal network activity is thought to require efficient functioning of astrocytes. Here, we analyzed neuron-astrocyte communication in the pre-Bötzinger Complex (preBötC) of rhythmic slice preparations from neonatal mice. In astrocytes that exhibited rhythmic potassium fluxes and glutamate transporter currents, we did not find a translation of respiratory neuronal activity into phase-locked astroglial calcium signals. In up to 20% of astrocytes, 2-photon calcium imaging revealed spontaneous calcium fluctuations, although with no correlation to neuronal activity. Calcium signals could be elicited in preBötC astrocytes by metabotropic glutamate receptor activation or after inhibition of glial glutamate uptake. In the latter case, astrocyte calcium elevation preceded a surge of respiratory neuron discharge activity followed by network failure. We conclude that astrocytes do not exhibit respiratory-rhythmic calcium fluctuations when they are able to prevent synaptic glutamate accumulation. Calcium signaling is, however, observed when glutamate transport processes in astrocytes are suppressed or neuronal discharge activity is excessive

    Developing an instrument to assess the endoscopic severity of ulcerative colitis : The Ulcerative Colitis Endoscopic Index of Severity (UCEIS)

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    Full list of Investigators is given at the end of the article.Background: Variability in endoscopic assessment necessitates rigorous investigation of descriptors for scoring severity of ulcerative colitis (UC). Objective: To evaluate variation in the overall endoscopic assessment of severity, the intra- and interindividual variation of descriptive terms and to create an Ulcerative Colitis Endoscopic Index of Severity which could be validated. Design: A two-phase study used a library of 670 video sigmoidoscopies from patients with Mayo Clinic scores 0-11, supplemented by 10 videos from five people without UC and five hospitalised patients with acute severe UC. In phase 1, each of 10 investigators viewed 16/24 videos to assess agreement on the Baron score with a central reader and agreed definitions of 10 endoscopic descriptors. In phase 2, each of 30 different investigators rated 25/60 different videos for the descriptors and assessed overall severity on a 0-100 visual analogue scale. κ Statistics tested inter- and intraobserver variability for each descriptor. A general linear mixed regression model based on logit link and β distribution of variance was used to predict overall endoscopic severity from descriptors. Results: There was 76% agreement for 'severe', but 27% agreement for 'normal' appearances between phase I investigators and the central reader. In phase 2, weighted κ values ranged from 0.34 to 0.65 and 0.30 to 0.45 within and between observers for the 10 descriptors. The final model incorporated vascular pattern, (normal/patchy/ complete obliteration) bleeding (none/mucosal/luminal mild/luminal moderate or severe), erosions and ulcers (none/erosions/superficial/deep), each with precise definitions, which explained 90% of the variance (pR2, Akaike Information Criterion) in the overall assessment of endoscopic severity, predictions varying from 4 to 93 on a 100-point scale (from normal to worst endoscopic severity). Conclusion: The Ulcerative Colitis Endoscopic Index of Severity accurately predicts overall assessment of endoscopic severity of UC. Validity and responsiveness need further testing before it can be applied as an outcome measure in clinical trials or clinical practice.publishersversionPeer reviewe

    Imprinted antibody responses against SARS-CoV-2 Omicron sublineages

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    Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron sublineages carry distinct spike mutations resulting in escape from antibodies induced by previous infection or vaccination. We show that hybrid immunity or vaccine boosters elicit plasma-neutralizing antibodies against Omicron BA.1, BA.2, BA.2.12.1, and BA.4/5, and that breakthrough infections, but not vaccination alone, induce neutralizing antibodies in the nasal mucosa. Consistent with immunological imprinting, most antibodies derived from memory B cells or plasma cells of Omicron breakthrough cases cross-react with the Wuhan-Hu-1, BA.1, BA.2, and BA.4/5 receptor-binding domains, whereas Omicron primary infections elicit B cells of narrow specificity up to 6 months after infection. Although most clinical antibodies have reduced neutralization of Omicron, we identified an ultrapotent pan-variant–neutralizing antibody that is a strong candidate for clinical development

    Imprinted antibody responses against SARS-CoV-2 Omicron sublineages

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    SARS-CoV-2 Omicron sublineages carry distinct spike mutations and represent an antigenic shift resulting in escape from antibodies induced by previous infection or vaccination. We show that hybrid immunity or vaccine boosters result in potent plasma neutralizing activity against Omicron BA.1 and BA.2 and that breakthrough infections, but not vaccination-only, induce neutralizing activity in the nasal mucosa. Consistent with immunological imprinting, most antibodies derived from memory B cells or plasma cells of Omicron breakthrough cases cross-react with the Wuhan-Hu-1, BA.1 and BA.2 receptor-binding domains whereas Omicron primary infections elicit B cells of narrow specificity. While most clinical antibodies have reduced neutralization of Omicron, we identified an ultrapotent pan-variant antibody, that is unaffected by any Omicron lineage spike mutations and is a strong candidate for clinical development
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