Two contaminating fungi were isolated from a bioreactor containing diethylketone and Streptococcus equisimilis, subsequently characterized at molecular level and identified as belonging to the Alternaria and Penicillium genera. The ability of these fungi to biodegrade DEK is evaluated. The kinetic parameters are estimated using four growth kinetic models for biodegradation of organic compounds available in literature. The experimental data for Alternaria sp. and Penicillium sp. was found to be better fitted by the Haldane and the Luong respectively. Biodegradation rate kinetics was evaluated using zero-order, pseudo-first order, pseudo-second order and three-half order models. The pseudo-second-order model was found suitable for all the concentrations of DEK tested for the biodegradation assays using Penicillium sp. whereas for the Alternaria sp. this model just describes properly the assays with initial concentrations of DEK higher than 0.5 g/L. The percentage of biodegraded DEK were approximately 100%, for all the initial concentrations tested.

A survey in 16 activated sludge wastewater treatment plants (WWTP) was conducted to contribute to the knowledge of the environmental parameters that determine the composition of the filamentous community. A total of 128 samples of mixed liquor from municipal WWTP were collected during 2 years, and 22 filamentous morphotypes were identified. The most frequent and abundant filamentous bacteria were, in both cases and by this order, type 0041/0675, type 0092, Microthrix parvicella and 1851, nocardioforms and Haliscomenobacter hydrossis. Concerning dominance, type 1851 was the most frequently dominant morphotype, followed by M. parvicella and types 0092 and 0041/0675. These were also, and by this order, the dominant morphotypes during bulking occurrences. Significant correlations were obtained between the abundance of filamentous bacteria and environmental parameters, but multivariate statistical analysis only confirmed the correlation between type 0092 and Sludge Volume Index (SVI), emphasizing the association of this filament with bulking. The discussion of the results in light of published works was complicated by the random use of terms such as frequency, abundance, and dominance with different and often unclear meanings. This reinforces the need of clarifying these terms when discussing the causes of filamentous overgrowth in WWTP.

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The abundance of arsenic-tolerant diazotrophic bacteria was compared in a long-term contaminated soil versus a non-contaminated one. In addition, the characterization of tolerant diazotrophic bacteria was carried out. Differences in the number of heterotrophic N 2 fixers were found between soils. Contaminated soil showed a decrease in the microbial population size of about 80%, confirming the great sensitivity of this group of soil bacteria to metals. However, quantitative analysis of the response to increased doses of arsenic reveals that the proportion of the culturable diazotrophic community tolerant to arsenic was identical for both soils (contaminated and non-contaminated). Twentytwo arsenic-tolerant diazotrophic isolates were obtained and further characterized. 16S ribosomal DNA sequence analysis revealed that these bacterial isolates were distributed among four taxons (Actinobacteria, Firmicutes, γ-Proteobacteria, and β-Proteobacteria). Most genera recovered from the contaminated soil were also found in the uncontaminated soil.

Fundamentos: A vacinação contra a COVID -19 é essencial para o controlo da pandemia. As reações adversas após a vacinação são comuns, embora a anafilaxia seja rara. Objetivos: Caracterizar as reações imunoalergológicas que motivaram referenciação pré -vacinação dos cuidados de saúde primários (CSP), analisar o impacto da alergia medicamentosa nesta referenciação e avaliar o resultado da vacinação após estratificação do risco. Métodos: Estudo observacional retrospetivo, com inclusão dos doentes referenciados à consulta de Imunoalergologia de um hospital terciário a partir dos CSP para avaliação do risco de reações de hipersensibilidade (RHS) graves à vacina contra a COVID -19 entre janeiro -junho de 2021. A estratificação do risco foi efetuada de acordo com o protocolo do serviço. Resultados: De um total de 733 doentes referenciados dos CSP, 510 foram admitidos, dos quais 445 foram avaliados, 369 (83%) do sexo feminino, média de idades 66±13 anos [20 -99 anos], 122 (27%) atópicos. A maioria (n=349, 78%) foi referenciada por reações prévias a medicamentos, dos quais 69 (15,5%) por reações a vacinas. Os anti -inflamatórios não esteroides (n=97, 51%) e os antibióticos (n=70, 36%) foram os mais reportados nas suspeitas/ hipersensibilidade confirmada a fármacos. O perfil das reações medicamentosas diferiu nos doentes de baixo risco (61% com RHS, 39% anafilaxia) e de risco intermédio/elevado (92% com RHS, 65% anafilaxia). Após avaliação, 323 doentes foram encaminhados para vacinação no centro de vacinação, dos quais 280 receberam pelo menos uma dose da vacina. Dois doentes tiveram agravamento da urticária crónica e uma teve reação vasovagal após a vacina. Foram vacinados em meio hospitalar 122 doentes, dos quais 69 receberam uma dose da vacina. Apenas dois apresentaram reações cutâneas ligeiras. Conclusões: A alergia medicamentosa foi o principal motivo de avaliação do risco pré -vacinação. A maioria dos doentes foi vacinada no centro de vacinação sem intercorrências. O protocolo utilizado foi eficaz, sem reações de relevo nem casos de anafilaxia.