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- Thallus structural alterations in green-algal lichens as indicators of elevated CO₂ in a degassing volcanic areaPublication . Bernardo, Filipe Miguel; Rocha, Tânia; Branquinho, Cristina; Garcia, Patrícia; Rodrigues, ArmindoWe hypothesize that the thalli of the green-algal, CO₂-sensitive lichen Usnea rubicunda (Stirton) undergo significant structural alterations as a biological response indicating increased CO₂ emissions. To test that, U. rubicunda thalli were transplanted from a reference site with no volcanism into 36 sites distributed within the volcanically active Furnas caldera, encompassing the gradient of soil diffuse CO₂ degassing areas (700 t d⁻¹ of hydrothermal CO₂). After 6 months of exposure in similar macroclimatic conditions, both Furnas transplants and samples kept at the reference site were retrieved for histology to assess thalli structure and the proportion between the symbionts. On average, cross-sections of Furnas thalli were significantly thicker than reference, owing mostly to the fungal layers of medulla and central cord. The latter occupied a significantly greater than reference relative volumetric density despite a smaller than reference relative percentage of algal occupation on Furnas thalli. These results reveal a positive and time-integrated response of U. rubicunda to the greater availability of CO₂ from hydrothermal emissions in the volcanic environment, translated in greater efficiency of the algae in sustaining the fungal biomass. Histomorphometric structural alterations in the heteromerous thalli of U. rubicunda are suitable response biomarkers with potential to indicate a global rise of CO₂ levels in natural environments.
- Occurrence of ESBL-producing Escherichia coli in soils subjected to livestock grazing in Azores archipelago : an environment-health pollution issue?Publication . Silva, Vanessa; Peixoto, Fernando; Parelho, Carolina Paula Furtado de Medeiros; Garcia, Patrícia; Rodrigues, Armindo; Silva, Adriana; Carvalho, Isabel; Pereira, José Eduardo; Igrejas, Gilberto; Poeta, Patrícia Alexandra Curado Quintas DinisAntibiotics are successful drugs used in human and animal therapy; however, they must be considered as environmental pollutants. This study aims to isolate and characterize the extended-spectrum β-lactamase (ESBL) producing Escherichia coli soil from Azores Archipelago subjected to livestock agricultural practices. Twenty-four soil samples were collected from three different pasture systems with different number of cattle heads, and from a control site. Antibiotic susceptibility method was performed by Kirby-Bauer disk diffusion method against 16 antibiotics, and the presence of genes encoding lactamases, antimicrobial resistance genes, virulence factors, and phylogenetic groups was determined by polymerase chain reaction (PCR). Nine ESBLs were recovered from the three grazing sites, and all isolates presented the beta-lactamase genes blaCTX-M-3 and blaSHV. E. coli isolates were resistance to tetracycline and streptomycin and harbored the tetB, strA, and strB genes. One isolate also showed resistance to sulfonamides, and the genes sul1 and sul2 were detected. The isolates were grouped into the following phylogenic groups: B1 (n = 6), D (n = 2), and A (n = 1). The presence of antibiotics and resistance genes in soils may be the source to the development of antimicrobial resistance, which may have negative consequences in human and animal health.
- Deficiency of essential elements in volcanic soils : potential harmful health effects on grazing cattlePublication . Linhares, Diana P.; Pimentel, Adriano; Garcia, Patrícia; Rodrigues, ArmindoSeveral essential nutrients such as Fe, Co, Cu, I, Se, and Zn are vital to grazing cattle as they play a significant role in intracellular enzyme systems, with antioxidant and repair functions of DNA lesions. Feeds may supply most essential nutrients in adequate amounts. However, essential nutrient deficiencies are common and are mainly related to the geochemical characteristics of the soils, inherited from parent rocks. This study aims to assess the concentrations of the selected essential nutrients in topsoils and pasture grass from São Miguel Island (Azores) and discuss the possible effects of its deficiency in grazing cattle health. Sixty-eight samples of agricultural (pastures) topsoil and thirty samples of pasture grass were collected throughout São Miguel Island in areas with basaltic and trachytic parent rocks. Soil physicochemical properties and geochemical baselines of selected elements were determined on composite samples of soil and pasture grass in each site. Results indicate that the highest concentrations of the selected essential nutrients were observed in areas with basaltic soils, while the lowest values were found in areas with trachytic soils. These differences are considered of geogenic origin since they result from the weathering of volcanic parent rocks with different geochemical compositions. Data indicate a lack of some essential nutrients in topsoils (Co and Se) and/or pasture grass (Co, Cu, Se, and Zn) that can contribute to harmful health effects on grazing cattle. The uneven distribution of essential nutrients in topsoil and pasture grass and their deficiency can lead to several health problems in the cattle since these elements regulate physiological functions in biological systems. The identification of these deficit sites is important as it can help farmers to implement soil and/or animal supplementation programs to diminish possible health problems.
- Drinking Bottled and Tap Water for Healthier Living in Volcanic Areas : Are All Waters the Same?Publication . Linhares, Diana P.; Gaspar, Diogo; Garcia, Patrícia; Rodrigues, ArmindoIn most volcanic areas, the population considers the use of bottled waters as a healthier and safer option. This study aimed to (i) assess the fluoride concentrations in tap and bottled water consumed on São Miguel Island, (ii) confirm the accuracy of the labeling of fluoride levels on bottled water, and (iii) assess the fluoride daily intake and risk exposure and discuss the possible health effects in adults and children. Fluoride concentrations were measured in tap water (49 samples) and bottled water (23 samples) with a fluoride ion-selective electrode. The fluoride concentration was above the recommended limit in tap water from Sete Cidades (1.71 mg/L), in bottled waters nº 5 and 7 from category C (2.05 ± 0.04 mg/L and 2.36 ± 0.14 mg/L, respectively), and in bottled water nº 5 from category D (1.92 ± 0.03 mg/L). Fluoride daily intake in children reached a maximum value in gasified water nº 7 (0.059 mg F/day/kg). The risk assessment evidenced that all the brands with over 1.2 mgF/L might be a concern for potential non-cancer health effects, especially in adults. The most recognized brands of gasified and gasified flavored waters represent a higher risk of exceeding fluoride daily intake when compared to tap and mineral bottled waters.
- Pulmonary oxidative stress and apoptosis in mice chronically exposed to hydrothermal volcanic emissionsPublication . Camarinho, Ricardo; Garcia, Patrícia; Choi, Hyunok; Rodrigues, ArmindoRecent studies have shown that exposure to hydrothermal emissions has a negative impact on the respiratory system. Still, volcanogenic air pollution studies are still outnumbered when compared to anthropogenic studies which can result in an unknown risk to the human populations living near volcanically active areas. This study was carried out in São Miguel Island, with noneruptive volcanically active environments, such as the Furnas volcano caldera. Its noneruptive volcanism presents itself as hydrothermal emissions, mainly by the release of nearly 1000 T d-1 of CO₂ along with H₂S, and the radioactive gas radon; metals [e.g., mercury (Hg), cadmium (Cd), copper (Cu), and zinc (Zn)] and particulate matter are also released in a daily basis. We test the hypothesis whether chronic exposure to hydrothermal emissions causes pulmonary oxidative stress, using Mus musculus as a surrogate species. Mus musculus was live-captured in two villages with hydrothermal emissions and one village without any type of volcanic activity. The level of pulmonary oxidative stress was immunohistochemically assessed by using an OxyIHCTM Oxidative stress detection kit, and the detection of terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end-labeling (TUNEL) was used to evaluate apoptosis in lung tissues. Mice chronically exposed to hydrothermal emissions presented increased levels of oxidative stress and amount of apoptotic cells. We demonstrate, for the first time, the high oxidative stress potential in the lungs of mice chronically exposed to hydrothermal emissions. This study highlights the usefulness of M. musculus as a bioindicator species and enforces the necessity of regularly biomonitor the inhabitants of hydrothermal areas to prevent respiratory pathologies.
- The Azorean edible abalone Haliotis tuberculata, an alternative heavy metal-free marine resource?Publication . Torres, Paulo; Rodrigues, Armindo; Prestes, Afonso L.; Neto, Ana I.; Álvaro, Nuno V.; Martins, Gustavo M.Abalones are considered a delicacy and exploited for food worldwide. In many places, overfishing has led to the decimation of wild stocks and many are now reared in aquaculture systems. In the Azores, there is no tradition of eating abalones and Haliotis tuberculata stocks are still virtually untouched. However, as tourism in the islands grows and the stocks of other shellfish diminish, there is an increasing pressure to find alternative edible resources, leading to a rising interest in abalones. According to previous studies performed in the region, other edible species, including the local highly appreciated limpets and the giant barnacle, present high concentration levels of some heavy metals, which has been attributed to the volcanic origin of the islands. Here we analysed the metal content in the edible tissue of Haliotis tuberculata from São Miguel Island, Azores. The potential human health risks due to its consumption was assessed by estimating the average daily intake (EDI) and target hazard quotient (THQ) of metals. Similarly to other organisms in the Azores, abalones have higher than normal levels of some heavy metals, particularly cadmium, reflecting a local natural source that should be closely monitored from a public health point of view.
- Evaluation of Respiratory, Genotoxic and Cytotoxic Effects from Occupational Exposure to Typography ActivitiesPublication . Linhares, Diana P.; Rocha, Joana Gonçalves; Rodrigues, Armindo; Camarinho, Ricardo; Garcia, PatríciaThis cross-sectional study was structured to allow the evaluation of the respiratory, genotoxic, and cytotoxic effects of occupational exposure to products resulting from the activity of printers in typographies and, to determine the risk of genotoxicity associated with such exposure. This study comprised 69 subjects, 25 individuals occupationally exposed to the products of typographies (study group), and 44 individuals non-exposed to the environment studied (reference group). The frequency of micronucleated cells and other nuclear anomalies (binucleated, karyolitic, pyknotic, and karyorrhectic cells) in the oral epithelia of each subject were analyzed. The frequency of micronucleated cells was significantly higher in the study group when compared to the reference one (12.96 MN/2000 cells vs. 4 MN/2000 cells, respectively). Occupational exposure to products of typography is a risk factor for the occurrence of micronucleated cells in the study group (RR = 3.2; 95% CI, 2.7–3.9; p < 0.001). The results of the spirometry test did not reveal significant respiratory effects between the reference and study groups.
- Bioaccumulation and potential ecotoxicological effects of trace metals along a management intensity gradient in volcanic pasturelandsPublication . Parelho, Carolina Paula Furtado de Medeiros; Rodrigues, Armindo; Barreto, Maria do Carmo; Cruz, José Virgílio; Rasche, Frank; Silva, Luís; Garcia, PatríciaThe particularities of volcanic soils raise the need to better understand the link between soil agricultural management intensity and trace metal bioaccumulation. The Azores are a region characterized by volcanic soils, which were changed in different degrees according to the intensity of the agricultural practices. The main objective of this study was to assess the potential ecotoxicological effects of the trace metals present in volcanic pastureland soils along a gradient of management intensity (i.e., semi-natural, permanent and reseeded), using earthworms (Eisenia fetida) as biological indicators. For this purpose earthworms were exposed during 7, 14, 28 and 56 days to soils from the three types of pastures. At each exposure time, we quantified trace element bioaccumulation (As, Cd, Co, Cr, Cu, Hg, Li, Mn, Mo, Ni, Pb, Rb, U, V and Zn) and the activities of superoxide dismutase and acetylcholinesterase in earthworm tissues. Overall, the results showed that the type of pastureland management significantly increased the soil contents in trace metals: V, Co, Ni and Zn in semi-natural pasturelands; As, Cd and Hg in reseeded pasturelands; and, Rb and U in both permanent and reseeded pasturelands. The soil physicochemical properties observed in the reseeded pastureland systems (higher electric conductivity values associated with a moderately acid pH value) modulated the metal bioavailability, from soil to biota, leading to a greater Hg bioaccumulation in earthworm tissues. The long-term exposure (56 days) of earthworms to reseeded pastureland soil was associated with adverse biological effects (intensification of AChE activity and decrease of SOD activity), encompassing key processes such as neurotransmission and antioxidant defence mechanisms in resident soil biota (earthworms). This study point towards the increased importance of semi-natural and permanent pastureland management, over the intensive management (reseeded pasturelands), in favour of more sustainable ecosystems.
- Occurrence of Volcanogenic Inorganic Mercury in Wild Mice Spinal Cord : Potential Health ImplicationsPublication . Navarro-Sempere, Alicia; García, Magdalena; Rodrigues, Armindo; Garcia, Patrícia; Camarinho, Ricardo; Segovia, YolandaMercury accumulation has been proposed as a toxic factor that causes neurodegenerative diseases. However, the hazardous health effects of gaseous elemental mercury exposure on the spinal cord in volcanic areas have not been reported previously in the literature. To evaluate the presence of volcanogenic inorganic mercury in the spinal cord, a study was carried out in São Miguel island (Azores, Portugal) by comparing the spinal cord of mice exposed chronically to an active volcanic environment (Furnas village) with individuals not exposed (Rabo de Peixe village), through the autometallographic silver enhancement histochemical method. Moreover, a morphometric and quantification analysis of the axons was carried out. Results exhibited mercury deposits at the lumbar level of the spinal cord in the specimens captured at the site with volcanic activity (Furnas village). A decrease in axon calibre and axonal atrophy was also observed in these specimens. Given that these are relevant hallmarks in the neurodegenerative pathologies, our results highlight the importance of the surveillance of the health of populations chronically exposed to active volcanic environments.
- O solo é fonte de vida!Publication . Linhares, Diana P.; Rodrigues, ArmindoO solo e um recurso natural não renovável, crucial para quase todos os aspetos da vida, apresentando-se como um componente fundamental do ecossistema terrestre. Consegue armazenar e filtrar água, atua na regulação da temperatura e na emissão de gases de efeito de estufa, promove a decomposição da matéria orgânica e a reciclagem de nutrientes. Contudo, este ecossistema dinâmico não tem a mesma composição em todas as partes do mundo; a pedogénese, processo de formação dos solos, aliada a intemperismos físicos e químicos, irá determinar as características geoquímicas e morfológicas dos solos conferindo-lhes determinadas especificidades que poderão contribuir para o enriquecimento, ou empobrecimento, de elementos químicos que são essenciais a vida. A concentração de elementos químicos no solo pode ser condicionada por fatores antropogénicos, como a aplicação de fertilizantes e agroquímicos, ou até mesmo por fenómenos naturais como o vulcanismo. Em regiões com atividade vulcânica, há um maior enriquecimento dos solos, resultante da libertação de materiais sólidos e gases, tornando-os bastante férteis devido a riqueza em elementos químicos essenciais que poderão ser integrados na cadeia alimentar através da absorção pelas plantas. […].
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