Investigation of potential respiratory adverse effects of micro/nanofibrillated cellulose and cellulose nanocrystals using human lung cell lines.

Abstract publicado em: Environ Mol Mutagen. 2022 Aug;63(Suppl 1):72-73. (Abstracts from the 13th International Conference on Environmental Mutagens and 53rd Annual Meeting of the Environmental Mutagenesis and Genomics Society). https://onlinelibrary.wiley.com/toc/10982280/2022/63/S1Micro/nanofibrillated (CMF/CNF) and nanocrystalline (CNC) celluloses are innovative materials with enormous potential for industrial and biomedical applications. Their expanding production/application urges the investigation of their safety for human health. This study aimed at investigating the potential respiratory outcomes of two CMF/CNF and one CNC produced from bleached Eucalyptus globulus kraft pulp using human alveolar epithelial (A549) cells grown in monoculture or co-cultured with THP-1 monocyte-derived macrophages, by assessing their cellular uptake, cytotoxic, immunotoxic, genotoxic, and epigenetic effects. The nanocelluloses were characterized for their physicochemical properties: CMF displays a low percentage of nanofibrils while CNF comprises 100% fibrils with a diameter (D) circa 11 nm; CNC consists of nanorods with D of 4-5 nm and aspect ratio around 42. TEM analysis evidenced that CMF and CNF were internalised into A549 cells whereas CNC were not. Neither cytotoxicity (colorimetric and clonogenic assays) nor ROS induction was observed for any of the nanocelluloses. CMF caused chromosomal alterations (in vitro micronucleus assay) in A549 cells while negative results were obtained in co-culture and for the other micro/nanocelluloses in mono- or co-culture. Results in progress of DNA damage and gene mutation analyses will complement mutagenesis assessment. Additionally, potential inflammatory and epigenetic effects are being evaluated. These results contribute to the weight of evidence of nanocelluloses biological effects and knowledge of the underlying molecular mechanisms. Such information will drive the synthesis of the safest nanocelluloses,thus minimising potential negative impacts of their use on human and environmental health.FCT/MCTES through nacional funds (PTDC/SAU-PUB/32587/2017; UIDP/00009/2020; UIDB/00009/2020; 020.07168.BD)info:eu-repo/semantics/publishedVersio

Cellular, Molecular and Genotoxic Effects of Digested Titanium Dioxide Nanomaterials

Abstract publicado em: Environ Mol Mutagen. 2022 Aug;63(Suppl 1):88. (Abstracts from the 13th International Conference on Environmental Mutagens and 53rd Annual Meeting of the Environmental Mutagenesis and Genomics Society). https://onlinelibrary.wiley.com/toc/10982280/2022/63/S1Human exposure to titanium dioxide nanomaterials(TiO2NMs) occurs particularly by ingestion, due to food/food contact materials and consumer products. However, the possibility of adverse effects in gastrointestinal tract is unclear. Aiming to study the impact of digestion on the NMs’ properties and their cellular/molecular effects, two human intestinal cell lines were used, Caco-2 and HT29-MTX-E12. After exposure to TiO2NMs(NM-102, NM-103, NM-105), undigested or subjected to standardized static in vitro digestion method (mimicking human digestion), the cells were analyzed for toxicity, genotoxicity, reactive oxygen species, NM uptake and intestinal translocation. We showed that in vitro digestion of TiO2NMs may increase their toxicity and DNA-damaging effect, depending on the NM, more relevant for the rutile/anatase NM-105, possibly due to its smaller hydrodynamic size in the cellular medium. Effects on chromosomal integrity were seen in HT29-MTX-E12 cells, for all tested TiO2NMs, especially after digestion. Internalization into early endosomes was confirmed for NM-103 and NM-105, before and after digestion, in monolayers of both cell lines, and at the apical membrane of polarized Caco-2 cells. The internalized NMs accumulated in late endosomes/multivesicular bodies, partially transversing the basolateral membrane of polarized Caco-2 cells without changing transepithelial electrical resistance or epithelial marker abundance. These results suggest that part of the TiO2NMs can be transcytosed through colonic epithelia without disrupting intestinal barrier integrity. Overall, the biological outcomes from TiO2NMs interaction with intestinal cells were more pronounced after digestion, highlighting its relevance in the hazard assessment of ingested NMs.Funded by FCT/MCTES through the projects: PTDC/SAU-PUB/29481/2017, UIDB/00009/2020; UIDP/00009/2020;UIDP/50017/2020+UIDB/50017/2020+LA/P/ 0094/2020; CEECIND/03143/2017 (LG), 2020.07168.BD (NV).info:eu-repo/semantics/publishedVersio

Growth and flowering of carnation cultivated in different pot colors and protected environments

The Dianthus caryophyllus L. occupies the second position of the best sold cut flowers after rose. The choice of the environment and the cultivation container is crucial for flower production because, besides permitting higher temperature, light, and relative humidity management, it also impacts yield. This study evaluated the cultivation of yellow carnation in different protected environments and pot colours. The experiment was conducted in a factorial 2 × 4 (greenhouse and nursery x blue, red, brown, and black pots; the black pot was considered the control treatment). The photosynthetically active radiation, substrate temperature, and meteorological variables in the environments were monitored during the experiment's conduction as well the growth and productivity variables. The greenhouse significantly reduced solar radiation, generating favourable conditions for the initial growth of carnation plants. The nursery maintained higher levels of solar radiation, stimulating its flowering. The cultivation in brown pots provided higher quality plants regarding both vegetative growth and flowering. Therefore, brown pots are an option to substitute the black pots traditionally used for flower production. The use of the blue pot negatively influenced the development of carnation plants

Efeitos dos excessos de alumínio, cloro e manganês em dois cultivares de soja (Glycine max (L.) Merrill)

Two soybean cultivars, Santa Rosa and FV-1, were grown in nutrient solution in the presence of high concentrations of Al (24 ppm), CI (1750 ppm) and Mn (25 ppm). Observations, measurements and chemical analyses allowed for the following conclusions to be drawn: (1) symptoms of toxicity are in agreement with those described in the literatura; (2) the detrimental effect obeyed the decreasing order - Mn Al CI; (3) dry matter production by the variety UFV - 1 was relatively more affected by the treatments; (4) leaf analyses do not provide a reliable indication of the sensitivity of the two varieties to the high levels of the three elements in the substrate; (5) Ca/Al ratio in the roots keeps a good relationship with the relative tolerance of the two cultivas to excess Al in the medium.Dois cultivares de soja, Santa Rosa e UFV-1, foram cultivados em solução nutritiva na presença de excesso de alumínio, cloro e manganês. Além de provocar o aparecimento de sintomas foliares (cloro e manganês) ou radiculares (alumínio), os elementos em excesso causaram diminuições no crescimento e impediram a produção de vagens. A análise mineral das folhas mostrou a influência dos tratamentos na composição do tecido