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- Blank samples assessed through multivariate control chart as an internal quality control tool of ICP-MSPublication . Gomez, Filipe; Gueifão, Sandra; Cabral, Izunildo; Castanheira, Isabel; Matos, Ana SofiaInductively coupled plasma mass spectrometry (ICP-MS) is one of the most suitable analytical techniques used to quantify inorganic components at trace concentrations. Being considered one of the key activities in a Quality Assurance system, the Internal Quality Control (IQC) reveals is of utmost importance when ICP-MS is used. Involving a continuous and critical assessment of the analytical methods and work routines of an analytical chemistry laboratory, the main propose of IQC is to continuously monitor the developed methodologies, as well as, to assess the reliability of the results. Within the IQC, the blank sample is an excellent tool, allowing to evaluate and monitor the quality of reagents, identify possible contaminations from the analytical processes resulting from the method and analytical processes, as well as to estimate the detection limits and the quantification limits for the trace elements analysed by ICP-MS. This study presents a methodology based on multivariate control (T2) charts for monitoring and assessing the stability of blank samples for Copper, molybdenum and lead. The proposed methodology grounds on the Statistical Process Control, where the T2 chart was designed to detect possible contaminations that may occur during the analytical method. To validate this approach, three univariate control charts, based on the Z scores, were built for each element and compared with the multivariate control chart output. The data analysis was performed using a set of blank samples collected between the years 2016 and 2018. Based on the data analysis results, the T2 chart was built and then validated through the correspondent three univariate Z charts. By comparing this set of charts it is possible to conclude that the T2 chart is in accordance with the results obtained by the three univariate charts. Although the mathematical complexity is high, this T2 chart revealed to be an appropriate IQC tool, when multi-elemental analyses are performed by ICP-MS.
- Human biomonitoring of multiple mycotoxins in the Portuguese population: strengths and limitations under risk assessmentPublication . Martins, Carla; De Boevre, Marthe; De Saeger, Sarah; Nunes, Carla; Torres, Duarte; Goios, A.; Lopes, Carla; Assunção, Ricardo; Alvito, Paula; Vidal, A.Mycotoxins constitute a relevant group of food contaminants with associated health outcomes such as estrogenic, immunotoxic, nephrotoxic and teratogenic effects. Although scarce data are available in Portugal, human biomonitoring (HBM) studies have been globally developed to assess the exposure to mycotoxins at individual level. This study aimed to present data for mycotoxins’ urinary biomarkers within a human biomonitoring study developed to assess the exposure of the Portuguese population, and to characterize the risk associated to the exposure. In the scope of the National Food, Nutrition, and Physical Activity Survey of the Portuguese General Population (2015-2016), 24h-urine samples from 94 participants were analyzed by liquid chromatography–mass spectrometry (LC-MS/MS) for the simultaneous determination of 37 mycotoxins’ urinary biomarkers. Data obtained were used to estimate the probable daily intake as well as the risk characterization applying multiple imputation, reverse dosimetry and hazard quotient approaches. Results revealed the exposure of Portuguese population to zearalenone, deoxynivalenol, ochratoxin A, alternariol, citrinin and fumonisin B1. Risk characterization data revealed a potential concern to some reported mycotoxins since the reference intake values were exceeded by some of the considered participants. The use of data at individual level, the collection of 24h urine samples, the performance of analytical method and the use of multiple imputation approach were identified as the main strengths of this study. The limitations identified were related with the use of excretion data obtained within animal studies and the absence of health based guidance values for urinary biomarkers that would allow a direct comparison. The present study generated, for the first time and within a HBM study, reliable data on internal exposure to multiple mycotoxins at individual level for the Portuguese population. These data contributes for supporting risk managers in the establishment of preventive policy measures to ensure public health protection.
- Nutrient content of food from burned areas of the Central RegionPublication . Gueifão, Sandra; Moreira, Tiago; Ventura, Marta; Delgado, Inês; Coelho, Inês; Castanheira, Isabel; Silva, José ArmandoForest fires are usually unexpected events leading to dramatic changes in all kinds of forest ecosystems, and they have a significant impact on flora. Fire mineralizes soil nutrients and returns plant-locked nutrients to the soil. Nutrients are lost from the ecosystem through the release of particulates and volatile compounds during the fire, and later through surface transport and leaching by rains1. Wildfires can play an important role in the environmental distribution of major and trace elements, including through their mobilization by fire-induced runoff and associated transport of soil and ash particles2. This study aimed to evaluate the selenium (Se), cobalt (Co), manganese (Mn), copper (Cu), lithium (Li) and zinc (Zn) content in cabbage, egg, potato and fruit samples in a total of 16 pools composed of 3 samples each at two different harvest periods. Cabbage samples from burnt zones were compared with a designated control sample from a non-burnt zone. Inductive Plasma Coupled Mass Spectrometry (ICP-MS) performed the determination of nutrient compounds. Previously, the samples underwent a heating block acid digestion with a validated time and temperature program. The analysis performed was under accordance with ISO 17025:20053 by analytical procedures. The lowest concentration founded in all nutrients was in fruits. The selenium and zinc content varied as follows: eggs> cabbage> potatoes> fruits. In the other hand, cabbage contained the highest cobalt and manganese content while eggs had lower values of copper. For lithium content, potatoes were the samples, which had lower values, than the eggs that contained higher values. The amount of the nutrients present in this study when compared to the control sample, the more pronounced increase recorded was for copper in the potato samples. Monitoring studies based on accredited methods are a powerful aid in assessing of exposure of affected populations.
- Dermatophytes’ identification by Matrix-assisted laser desorption ionization-time of flight mass spectrometry. (MALDI-TOF MS) - the experience of a clinical laboratoryPublication . Verissimo, C.; Simões, H.; Sabino, R.; Simões, D.Objectives: Dermatophytes are a challenging group of fungi that infect the keratinized tissues. The taxonomy of these fungi has changed recently with the reclassification of some species and description of new ones. However, many clinical laboratories still base the identification of dermatophytes on their phenotype. Since dermatophytes are very pleomorphic, macro and micromorphology are often insufficient to reach a correct classification and may lead to misidentifications. The identification based on MALDI-TOF relies on the protein profile of the microorganism. Thus, this study aims to summarize our current laboratorial experience of dermatophyte identification using MALDI-TOF MS. Methods: From january to april 2018, 95 dermatophytes isolates, collected from human keratinized samples and also from quality control programs were characterized by phenotypic analysis, and by VITEK MS V3.2 bioMerieux. Before identification procedure, isolates were inoculated on Sabouraud Dextrose agar plates and incubated at 27°C during 5 to 10 days. Species were identified taking into account clinical features, as well as cultural, microscopic and physiological characteristics. Prior to MALDI-TOF MS analysis, the samples were pre-treated according to the manufacturer’s protocol for filamentous fungi. Molecular identification by sequencing of the internal transcribed spacer 1 (ITS1) was performed in 34 of those isolates Results: Through phenotypic analysis eight different species were identified (54 Trichophyton rubrum; 4 T.soudanense; 22 T.interdigitale; 1 T.mentagrophytes; 3 T.tonsurans; 7 Microsporum canis; 3 M.audouinii; 1 Microsporum spp.- (non canis or audouinii). MALDI-TOF analysis showed an identification agreement in 80 cases (84,2%) with a confidence level of 99,9%. Eight isolates showed divergent identification results: three T.rubrum were identified as T.violaceum, three T.soudanense were identified as T.rubrum, one T.mentagrophytes was identified as T.interdigitale and one T.tonsurans was identified as T.rubrum. In four cases MALDI-TOF analysis did not get a profile. The ITS sequencing analysis of discrepant results corroborated the MALDI-TOF identification in five of them. On the other hand, T.soudanense was only identified by phenotypic analysis since MALDI-TOF and ITS sequencing result was T.rubrum. MALDITOF identification of T.violaceum was not confirmed by ITS sequencing that identified T. rubrum instead, in accordance with the phenotypic identification. Conclusion: Correct identification of dermatophytes to species level requires sequencing of the ITS, LSU, and/or betatubulin regions. The implementation of this methodology in a clinical laboratory is expensive and time consuming. MALDI-TOF identification is a good option for dermatophytes’ identification performed in laboratory routine, since costs of consumables as well as time of sample preparation are lower than for PCR analysis and doesn’t require long training period as phenotypic identification does. In this study, however, both methods failed to identify some species variants like Trichophyton soudanense or T. violaceum. The combined use of both MALDI-TOF and phenotypic methods seems to be the better approach for dermatophytes’ identification since some species show significant phenotypic and clinical differences.
- Contribution of EQA to improve Preanalytical practices by systematic verification of Laboratory ServicesPublication . Cardoso, Ana; Ventura, Catarina; Viegas, Silvia; Faria, Ana PaulaInternational literature describes the preanalytical phase as the most susceptible to errors due to the numerous non automated activities it involves Most EQA organizers offer preanalytical schemes to participants. There are basically three types of surveys procedures registration, samples circulation and errors registration The Portuguese EQA Programme ( provides these type of schemes for 13 years, using as a guide the ISO 15189 2012 In order to improve the evaluation of the preanalytical phase, PNAEQ recently launched two other preanalytical EQA schemes, mystery client and presential audits in 2015 and 2016 respectively. The aim of the mystery client survey is to verify whether the information provided to the patient is constant regardless the day and time or if it is dependent on the collaborator. The aim of the presential audit survey is to give the participants a tool to verify if the procedures performed daily are in accordance with laboratorial good practices recommendations. Conclusions: Results from Mystery Client surveys demonstrate the need for written procedures and harmonization of practices for all collaborators, as more than a third of the responses differed in date/time and operator in a global view. In the Presential Audit surveys we highlight as critical points the results regarding questions 3 5 and 6 as they point to specific problems that occurred during the blood collection procedure, such as operator and patient safety, as well as the quality of the sample collected, suggesting the need to review legal and normative issues and to train collaborators. Participants who use systematically these two methodologies are monitoring some of the requirements of ISO 15189:2012, namely 4. 1.2.6, 4.3, 4.4.1, 4.14, 5.4.2 (both), 5.4.4.2 (mystery client) and 5.1.2, 5.2.2, 5.2.5, 5.3.2.5, 5.3.2.7, 5.4.4 (presential audit), contributing to release reliable results for medical decisions. For the future, we will extend the questions and items in evaluation in these two surveys to Microbiology area and continuing to offer training in Preanalytical matters.
- Evaluation of quality control viral load HIV results from two laboratories in Maputo, after the 3rd Congress of Laboratory Quality Control for Portuguese-Speaking Countries, MozambiquePublication . Faria, Ana Paula; Miranda, Armandina; Aguiar, Carmen; Sidume, Zita; Manguene, Yolanda; Vubil, Adolfo; Mabunda, Ana Flora; Manhumane, Isabel; Meijer, PietThe Project of Laboratory Quality Improvement for Portuguese Speaking Countries (ProMeQuaLab) is based on three major work tools: education, training and monitoring of quality control measures, in order to build capacity to implement and sustain good laboratory practices. Since 2015, a biennial congress on quality control is organised which includes also courses in this field. The third edition of the Congress was held in Mozambique in May 2019. Theoretical and practical courses concerning internal (CQI) and external quality control (EQA), calculation of Total Error (TE) and Measurement Uncertainty (MU) were held. Two practical work sessions were organized, with the trainers of the quality control courses and trainees from two laboratories, Centro Criança Dream (Dream) and Laboratório de Virologia Molecular (INS) in Maputo (Mozambique), to applied the statistical tools to evaluate their quality control results of viral load HIV from 2018. Evaluation of viral load is strongly recommended by WHO for monitoring response to retroviral treatment. The objective of this work was the implementation of the concepts and tools of the assessment of bias and uncertainty presented in the quality control courses and their application on the quantitative quality control results from 2018 of RNA viral load HIV-1 from two laboratories from Maputo. The concepts and tools presented in quality control courses were applied to quality control results of two laboratories in Maputo (Mozambique) for the measure of imprecision, bias and measurement uncertainty. The courses and the work sessions have proved to be very effective in transferring knowledge and skills and therefore should be continued with other laboratories. The results of the bias and measurement uncertainty show that the INS laboratory (Cobas Ampliprep TaqMan96) had a better performance in comparison to the Dream laboratory (Abbott m2000). Effort must be made to continue the education program, namely the interpretation of the quality control results to achieve an improvement of the evaluation of patient results.
- Caracterização do perfil de ácidos gordos de alimentos consumidos pela população portuguesaPublication . Gomes, Leonor; Fontes, Tânia; Vilarinho, Fernanda; Tavares, Nelson; Santos, Mariana; Castanheira, IsabelIntrodução: De acordo com o estudo Global Burden of Disease (GBD) realizado em 2017, os hábitos alimentares inadequados dos portugueses foram o terceiro fator de risco que mais contribuiu para a perda de anos de vida saudável. Na última década, diversos estudos epidemiológicos têm evidenciado uma relação entre a saúde e o consumo de certos tipos de gordura, nomeadamente pela ingestão de alguns ácidos gordos específicos. Objetivo: Caracterizar o perfil em ácidos gordos de três grupos de alimentos representativos dos hábitos/consumos alimentares da população portuguesa. Metodologia: Os grupos de alimentos estudados foram: Grupo do Peixe, produtos da pesca, anfíbios, répteis e invertebrados; Grupo dos Cereais e produtos à base de cereais e Grupo dos Pratos compostos. A recolha de amostras e sua preparação foram efetuadas no âmbito do Projeto TDS piloto (estudos de dieta total (TDS)) enquadrado no Projeto Europeu TDSExposure. Para a determinação do perfil de ácidos gordos, realizou-se a extração e metilação dos ácidos gordos em ésteres metílicos, seguida de análise por cromatografia gasosa acoplada a detetor de ionização de chama. Resultados: De acordo com os resultados obtidos, os valores de gordura total variaram entre 0,8 g/100g (Massa cozida) e 23,4 g/100g (Bolachas de chocolate). O valor mais elevado de ácidos gordos saturados (AGS) por 100g de alimento, foi observado no grupo dos Cereais e produtos à base de cereais (Bolachas de Chocolate (12,5 g/100 g)), enquanto que, o valor mais baixo de ácidos gordos saturados quantificado foi encontrado na amostra de Salmão (3,1 g /100 g). Os valores de ácidos gordos monoinsaturados (AGMI) variaram entre 0,1 g/100g (Caldo verde) e 9,9 g/100 g (Queque). O teor mais elevado de ácidos gordos polinsaturados (AGPI) foi encontrado no grupo do Pescado. Todos os alimentos analisados apresentaram valores de ácidos gordos trans (AGT) inferiores a 0,05 g/100 g (limite de quantificação do método), com exceção das amostras de Croissant e de Almôndegas, que apresentaram o valor 0,3 g/100 g. Conclusões: De acordo com os resultados obtidos, os teores mais elevados de ácidos gordos saturados (AGS), monoinsaturados (AGMI) e polinsaturados (AGPI) foram encontrados nos alimentos do grupo dos Cereais e produtos à base de cereais, tendo sido também os que apresentaram maiores teores de gordura total. O valor mais baixo de AGS foi encontrado nos alimentos do grupo do Pescado.
- PNAEQ - 13 years of post-analytical EQAS in PortugalPublication . Cardoso, Ana; Gizela, Santos; Faísca, Marília; Luís, Rosário; Faria, Ana PaulaIn the last 13 years, PNAEQ provided a specific program on post-analytical phase. In order to raise the offer of schemes in areas like Thrombosis/ Haemostasis, PNAEQ has established a consortium with ECAT Foundation distributing two more schemes: Post- Analytical Platelet Function and Pre- and Post-Analytical in Haemostasis. Furthermore, five of the analytical schemes organized by PNAEQ include a post-analytical interpretation, such as Blood Morphology, Hemoglobinopathies, Hydatidose, Rubella and Toxoplasmosis. The main objective of implementing specific and integrated programs on post-analytical phase is to evaluate the performance of laboratories on these matters in order to improve their quality service. The specific program on post-analytical phase provided by PNAEQ comprises 6 types of surveys: audits (vertical and presential), case simulation, case-study, document evaluation, quality indicators and questionnaires. Each survey represents a different tool to evaluate several items of the post-analytical process (Table 1), as well as the laboratory collaborators involved in each task (Figure 1). The items in evaluation are annually selected in the PNAEQ Working Group on Pre- and Post-Analytical Phase (created in 2015) and in compliance with the Portuguese Legislation and the ISO 15189:2012(E). Since 2007 PNAEQ has distributed 6 types of tools in the Post-Analytical Phase EQA, stabilizing in 3 of them in the last five years: Audits, Case Simulation and Quality Indicators. The participation rate has been increasing since 2015, which can be due to the multiple actions performed by PNAEQ Working Group on Pre- and Post-Analytical Phase. In addition, the Case Simulation surveys are the most participated (74% average) since the participation depends on PNAEQ. For the future, PNAEQ and the Working Group will work on the continuous update of the tools content distributed in each survey according to international references and the experience of other EQA organizers.
- Hortícolas e as suas propriedadesPublication . Albuquerque, T.G.Apresentação sobre as hortícolas e as suas propriedades.
- Hospital environment: water supply and containment of aerosolised fungal particles. How far must we go in times of antimicrobial resistance?Publication . Sabino, RaquelInvasive fungal infections depend on the interplay between host susceptibility and environmental exposure. Therefore, hospital environment is one of the major concerns in the management of nosocomial fungal infections, especially in wards bearing immunocompromised patients. Particular attention should be paid to the environmental risks associated with water since fungi can be aerosolized at water taps and showers. This may lead to fungal exposure by inhaled and ingested droplets, or even by direct contact with mucosae. Studies report that filamentous fungi and yeasts are commonly found on water-pipe inner surfaces, even in the presence of free chlorine. Air levels of Fusarium and Aspergillus conidia were found to increase in hospital environments after running showers multiple times. Species of these two genera are described as the most frequently found in this setting due to their conidial dispersion mode, as well as their ability to form biofilms. Despite the intrinsic resistance found in some species of these two genera, fungal exposure to antifungal agents via medical or agricultural use of these compounds, appears to have a major impact on acquisition of resistance to azoles; namely in Aspergillus fumigatus. The isolation of this species in hospital water and water reservoirs is therefore an even bigger matter of concern. More recently, several reports on nosocomial outbreaks caused by Candida auris have been described. This species is resistant to several classes of antifungals and is associated with high mortality. Contamination of hospital environment or transient colonization of medical devices and equipment may display an important role in the transmission of this species. C. auris was already found in water samples and therefore this reservoir should not be excluded as possible source of infection. In conclusion, fungal counts and detection of potential pathogenic species in water were, until a few years ago, the major concern of clinical and scientific community towards the reduction of nosocomial fungal infections originating in water devices. The emergence of infections caused by fungal isolates with intrinsic or acquired antifungal resistance triggered new levels of alert in this field.