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- Food Contaminants and Global Health Impact: an overview of recent intestinal in vitro modelsPublication . Sousa, Bruna; Alvito, PaulaFood safety and security are two complementing elements of our sustainable future. Future food security needs to be sustainable without compromising food safety to achieve the United Nations sustainable development goals (SDG). Human health and environmental are interlinked through diet since food ingestion is one the main routes of exposure to several contaminants. The intestine is an important digestive organ of the human body, and its barrier is the guardian of the body from the external environment. The impairment of the intestinal barrier is believed to be an important determinant in various foodborne diseases. Therefore, understanding the mechanisms of the impact of the food contaminants on intestinal barriers is essential for promoting human health. In vitro studies with different cell lines are a great option to predict the in vivo response. Over the last 20 years, Caco-2 (cell culture derived from a colorectal adenocarcinoma) have been the most widely use cell model. However, nowadays there are other types of cell models with fewer limitations. Organoids (stem cell-derived 3D culture systems) and organs-on-chip (multi-channel 3-D microfluidic cell culture, a type of artificial organ) models has been used to study some intestine mechanisms once these models can recapitulate the physiological morphology of 3D intestinal cells and tissues or restore other important differentiated intestinal functions. In this study, a literature search was performed with the objective of identifying publications on food contaminants and most recent intestinal cell models, from 2018-2022. The literature search using the terms “organ-on-a-chip”, “food contaminants” or “intestine”, “cell models”, “organoids”, “organ-on-a-chip” was performed using the database PubMed. The literature search identified 21 publications. Until now only one paper reported the use of food contaminats (dioxins) and recent intestinal in vitro models (gut-on-a-chip). At present, the cost of manufacturing and experimental implementation is still relatively expensive, which is not conducive to the widespread use of organ chips. The organ-on-a-chip is in the list of top 10 emerging technologies and a promising alternative to the use of animals in toxicological studies. In the future it is possible that these models will be used to study the relationship between the intestine and food contaminants.
- Large increase in bloodstream infections with carbapenem-resistant Acinetobacter species during the first 2 years of the COVID-19 pandemic, EU/EEA, 2020 and 2021Publication . Kinross, Pete; Gagliotti, Carlo; Merk, Hanna; Plachouras, Diamantis; Monnet, Dominique L; Högberg, Liselotte Diaz; EARS-Net Study Group; EARS-Net Study Group participantsBloodstream infections (BSIs) with Acinetobacter species commonly have poor outcomes, especially in intensive care unit (ICU) patients [1]. Acinetobacter spp. is intrinsically resistant to many antimicrobials, and additional acquired resistance further complicates the treatment of serious infections in already vulnerable patient groups. Recent data from the European Antimicrobial Resistance Surveillance Network (EARS-Net) show a large and statistically significant increase in reports of Acinetobacter spp. BSIs in the European Union (EU) and European Economic Area (EEA) during the period from 2017 to 2021 [2]. Most of this increase occurred in 2020 and 2021, the first years of the coronavirus disease (COVID-19) pandemic. Here we further explore this trend in a subset of data from laboratories that continuously reported data during that period.
- Ancestry of the α-MRE Associated with the 3.7kb α-Thalassemia Deletion in the Portuguese PopulationPublication . Pena, Rita; Lopes, Pedro; Gaspar, Gisela; Miranda, Armandina; Faustino, PaulaThe α-major regulatory element (α-MRE), also known as HS-40, is located upstream of the α-globin gene cluster and has a crucial role in the long-range regulation of the α-globin gene expression. It is genetically polymorphic and six haplotypes (A to F) have been identified in different populations. The D haplotype was primary described in African populations and is nearly absent in other populations. The aims of this study were to identify the α-MRE haplotype associated with the common 3.7kb α-thalassemia deletion (-α3.7del) in the Portuguese population, and to investigate its ancestry. We searched for the -α3.7del in 111 selected Portuguese individuals by Gap-PCR. In addition, a DNA fragment containing the α-MRE was amplified by PCR and Sanger sequenced. Statistical analysis was performed using R software. Fifty individuals have the wild-type α-globin genotype (group I), 34 are heterozygous for the -α3.7del (group II) and 27 are homozygous (group III). Regarding the α-MRE, four haplotypes were found (A to D). The ancestral A haplotype is predominant in all groups. The B haplotype is the second most frequent in groups I and II, whereas in group III haplotype D is the second most prevalent. Concerning genotypes, the α-MRE AA and AB are the most common in group I, while genotype AD is more prevalent in group III. In fact, 71.4% of AD individuals are homozygous for the -α3.7del. Moreover, the distribution of α-MRE haplotypes and genotypes are significantly different between groups with and without the -α3.7del (p<0.001). Furthermore, multiple correspondence analysis revealed that individuals without the -α3.7del are grouped with other European populations, while samples with the -α3.7del are split from these and found to be more closely related to the African population. This study revealed for the first time an association of a specific α-MRE haplotype with the common -α3.7del in the Portuguese population, and its likely African ancestry. These results may have clinical importance as the D haplotype has an alteration in the consensus sequence for the AP-1/NF-E2 binding site and in vitro experiments showed a decrease in its enhancer activity on α-globin genes.
- Adaptive evolution of PB1 from influenza A(H1N1)pdm09 virus towards an enhanced fitnessPublication . Santos, Luís A.; Almeida, Filipe; Gíria, Marta; Trigueiro-Louro, João; Rebelo-de-Andrade, HelenaPB1 influenza virus retain traces of interspecies transmission and adaptation. Previous phylogenetic analyses highlighted mutations L298I, R386K and I517V in PB1 to have putatively ameliorated the A(H1N1)pdm09 adaptation to the human host. This study aimed to evaluate the reversal of these mutations and infer the role of these residues in the virus overall fitness and adaptation. We generate PB1-mutated viruses introducing I298L, K386R and V517I mutations in PB1 and evaluate their phenotypic impact on viral growth and on antigen yield. We observed a decrease in viral growth accompanied by a reduction in hemagglutination titer and neuraminidase activity, in comparison with wt. Our data indicate that the adaptive evolution occurred in the PB1 leads to an improved overall viral fitness; and such biologic advantaged has the potential to be applied to the optimization of influenza vaccine seed prototypes.