What’s new about sample quality in routine coagulation testing?

Today, laboratories are very much different than they were decades ago. They have improved instruments to work with, multiple off-site collection points, more competent personnel, a greater analyte panel and quality requirements for those analytes. Nevertheless, sample quality has to be assured along the total testing process (TTP) in order to guarantee reliable results to the patient. In routine coagulation, prothrombin time (PT), activated partial thromboplastin time (APTT), fibrinogen (Fbg) and D-dimer are the essential part of the test panel, for which new evidences about sample quality requirements have been presented in recent years

Analytical quality specifications in the clinical laboratory: limiting analytical error with allowable error limits.

A função dos laboratórios clínicos é fornecer informações para decisões médicas no tratamento de doentes. Essa informação deve ser tão correta quanto possível, e o erro associado limitado a valores aceitáveis tendo em conta o uso médico pretendido. O estabelecimento de limites de erro ou especificações de qualidade analítica baseia-se na hierarquia de consenso definida em Estocolmo (1999). Os laboratórios devem ter como meta a definição de especificações a partir de modelos mais elevados na hierarquia, sempre que existam dados disponíveis, e o desempenho atual dos métodos o permita. A qualidade dos processos de medição pode ser avaliada através da métrica Sigma.Abstract: Clinical laboratories work to provide information for medical decisions on patient management. That information should be as correct as possible, and the associated error limited to a certain amount that is tolerable for medical purposes. A consensus hierarchy of models has been established in Stockholm (1999) to define such allowable error limits or analytical quality specifications. Laboratories should aim for higher models in hierarchy whenever data is available, and current method performance allows achieving the goal. Sigma-metrics can be used to assess the quality of measurement procedures

Convergence among EU Regions (1990-2001): Quality of National Institutions and "Objective 1" Status

This article focuses on convergence in terms of output per working-age person across regions in the European Union for the period 1990-2001. Controlling for the quality of national institutions, we investigate whether the status of “objective 1” region improves the speed of convergence as compared to what would be expected, given the regions’ initial conditions. We find evidence of conditional convergence among EU regions, with the quality of national institutions having a positive impact, but no evidence on a correlation between the eligibility for objective 1 and faster convergence.Convergence, economic growth, European Union, institutions

Worldwide prevalence and distribution of acquired AmpC-β-lactamases in Enterobacteriaceae lacking inducible AmpC

Introduction: Acquired AmpC beta-lactamases (qAmpC) which confer resistance to cephamycins and reduced susceptibility to extended-spectrum cephalosporins and β-lactamase inhibitors have increasingly been recognized as an emerging problem worldwide. qAmpCs enzymes are grouped according to the DNA sequence similarity with natural chromosomal AmpCs of some Enterobacteriaceae species, namely C. freundii (CMY-2-like, LAT-1, CFE-1), Enterobacter spp. (ACT-1-like, MIR-1-like), M. morgannii (DHA-1-like) and H. alvei (ACC-1-like), and with Aeromonas spp. (CMY-1-like, FOX-1-like, MOX-1-like). Isolates harbouring qAmpCs are usually multirresistant, and inappropriate empirical therapy is associated with high mortality ratios in invasive infections. Objectives: Estimate the worldwide prevalence and distribution of qAmpC types. Methods: We conducted a literature review on pertinent articles published between 2000 and 2011 on qAmpC detection and prevalence in Enterobacteriaceae lacking inducible AmpC [E. coli (EC), K. pneumoniae (KP), K. oxytoca (KO), P. mirabilis (PM) and Salmonella spp. (SM)] isolated from human infections. Estimated relative frequencies were calculated for qAmpC types detected in each country with relevant articles. Results: A total of 26 relevant studies from 21 countries on qAmpC epidemiology were retrieved, comprising 216648 isolates (182573 EC, 18858 KP, 8117 SM, 2340 PM, and 2278 KO). qAmpCs were detected in all but one study from Brazil, being the worldwide overall prevalence 0.55% (1194/216648, or 5.5 qAmpC producers per 1000 isolates). Countries with higher prevalence were China (4%), South Korea (3.5%), Portugal (3%) and Poland (3%), and the lowest were observed in Brazil (0%), Japan (0.08%), Switzerland (0.16%) and Belgium (0.16%). The overall species specific prevalence was 4.1%, 3.5%, 1.4%, 0.5% and 0.2% in SM, PM, KP, KO, and EC respectively. China presented the higher prevalence for KP (7%) and KO (3%), Thailand for EC (2%), while for PM and SM it was Poland (20.5%) and Mexico (7.7%), respectively. Globally, the main qAmpC variants detected were CMY-2 (53.1%), DHA-1 (30.6%) and CMY-2-like (11.7%). CMY-2 was predominantly present in EC, PM and SM isolates while DHA-1 was detected mostly among KP and KO. In countries like South Korea, China, and Portugal DHA-1 is the dominant variant, while in North America, Norway, Danmark, Tailand, Japan, Algeria and Spain is CMY-2. Conclusion: Although qAmpC prevalence is globally low, the results suggest that it is rising. This study also demonstrates that CMY-2 is the most prevalent qAmpC followed by DHA-1. Future studies are needed in order to monitor the spread of this emerging resistance mechanism

Resistência aos antibióticos: uma ameaça crescente a nível europeu

Durante a última década tem-se verificado um aumento das taxas de resistência antimicrobiana dos principais agentes patogénicos, sobretudo em bactérias de gram negativo (K. pneumoniae, E. coli e P. aeruginosa). Infeções complicadas por isolados multirresistentes (MDR), extremamente resistentes (XDR) e completamente resistentes (PDR - Pandrug-resistant) são cada vez mais frequentes, e por isso difíceis de tratar. O consumo exagerado e inapropriado de antibióticos tanto na medicina humana como animal tem sido reconhecido como uma das origens do problema, constituindo um importante fator de pressão seletiva conducente à emergência e disseminação de bactérias resistentes e/ou genes de resistência aos antibióticos.O impacto clínico da resistência antimicrobiana requer o estudo dos mecanismos implicados de modo a contribuir para uma adequação rápida e dirigida do tratamento assim como para o seguimento e controlo epidemiológico. O laboratório de microbiologia representa portanto um papel de vital importância

The generation and transmission of pressure fluctuations in pump suction lines.

Dissertation submitted for the degree of Doctor of Philosophy of the University of Bat

Interactive Air Traffic Control automation in oceanic airspace

Air traffic controllers workload limits impose upper bounds to the amount of traffic manageable in a given air sector for a given time frame. Air Traf- fic Control (ATC) automation methods open the possibility of reducing this workload by shifting to the machine the tasks of (1) detecting poten- tial conflicts, and of (2) proposing to the controller ATC instructions that prevent such conflicts. We propose a decision support system based on a combinatorial optimization approach using a branch-and-bound method. Given a known traffic situation, we proceed by simulating the trajecto- ries of traffic, taking into account possible instructions to separate traffic. In this study we considered only flight level change instructions, given at report fixes. The cost function employed includes both a measure of vertical deviation from the filed flight plan (FPL) and the total amount of ATC instructions. The multi-criteria problem is solved interactively, as the operator directs the algorithm towards the solution, indicating its preferences at intermediate points in the simulation. As a case study, we analyse the problem of oceanic airspace, where conventional ATC is used due to the lack of radar coverage

Simulação computacional do escoamento do ar no interior de um auditório

Tese de mestrado integrado. Engenharia Mecânica. Faculdade de Engenharia. Universidade do Porto. 201