Browsing by Author "Camarinho, Ricardo"
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- Chronic exposure to volcanic gaseous elemental mercury : using wild Mus musculus to unveil its uptake and fatePublication . Camarinho, Ricardo; Navarro-Sempere, Alicia; Garcia, Patrícia; García, Magdalena; Segovia, Yolanda; Rodrigues, ArmindoVolcanoes are a natural source of gaseous elemental mercury (GEM) (Hg0). Monitoring GEM releases of volcanic origin has been widely studied; however, few studies have been performed about the biomonitoring of species exposed to GEM, rendering an unknown risk to the worldwide populations living in the vicinity of an active volcano. In this pilot study, we used Mus musculus as a bioindicator species to understand to what extent lungs are the main route of mercury uptake in populations chronically exposed to active volcanic environments. Autometallographic silver protocol was used to detect mercury deposits in the histological lung slides. Abundant mercury deposits were found in the lungs of specimens captured at the site with volcanic activity (Furnas Village, S. Miguel Island—Azores). The presence of mercury in the lungs could represent not only hazardous effects to the lung itself but also to other tissues and organs, such as brain and kidneys. This study confirms that the main uptake route for GEM is the lungs and that, even at very low concentrations in the environment, a chronic exposure to Hg0 results in its bioaccumulation in the lung tissue. These results reinforce that biomonitoring studies should be combined with monitoring classical approaches in order to better characterize the risks of exposure to Hg0 in volcanic environments.
- Dendrochronological potential of the Azorean endemic gymnosperm Juniperus brevifolia (Seub.) AntoinePublication . Pavão, Diogo Cláudio; Jevšenak, Jernej; Petrillo, M.; Camarinho, Ricardo; Rodrigues, Armindo; Silva, L. Borges; Elias, Rui B.; Silva, LuísTree-ring inter-annual pattern variation is crucial in dendrochronology, allowing the identification of possible limiting factors on growth. Thus, trees exposed to subtropical or tropical climates without a marked seasonality may show a low degree of interannual variation, impeding a straightforward dendroclimatological approach. Meanwhile, subtropical regions, and areas in transitional climates such as the Azores archipelago, are widely unexplored in terms of dendroclimatology, providing opportunities to work with endemic trees, including the dominant Azorean tree Juniperus brevifolia (Seub.) Antoine. To evaluate the dendrochronological potential of J. brevifolia, we analyzed tree-ring patterns, crossdating capabilities, and correlation with climate parameters. We sampled 48 individual trees from two natural populations (São Miguel and Terceira islands) using an increment borer. Besides, a Trephor tool was used to obtain wood microcores for micro-anatomical analysis. Although the transition between early and latewood was evident, partially indistinct ring boundaries and wedging rings were present in some cases, affecting the crossdating process, but not impeding the establishment of reliable ring-width chronologies. Following detrending, master chronologies were built and correlated with monthly temperature and precipitation data using the treeclim R package. The climate-growth relationships indicated negative correlations with late summer temperature in both populations. Considering our results and the importance of J. brevifolia as a dominant tree in the Azores natural forests, we conclude that it shows an acceptable potential for dendrochronological research. Thus, this study provides baseline information to help fill the knowledge gap regarding the climate-growth relationship of Azorean trees.
- Epithelial morphometric alterations and mucosecretory responses in the nasal cavity of mice chronically exposed to hydrothermal emissionsPublication . Camarinho, Ricardo; Pardo, A. Madrero; Garcia, Patrícia; Rodrigues, ArmindoAir pollutants (either of natural or anthropogenic origin) represent a considerable environmental risk to human health by affecting the respiratory system and causing respiratory disorders. In this study, we investigate the effects of chronic exposure to hydrothermal emissions on the nasal cavity of mice since it is the first and the most exposed region of the respiratory system. This study, carried in S. Miguel Island, Azores—Portugal, used Mus musculus as a bioindicator species. Mice were captured in an area with non-eruptive active volcanism (Furnas Village) and another area without volcanism (Rabo de Peixe, reference site). The hydrothermal emissions present at Furnas Village are characterized by the continuous release of several gases (CO₂, H₂S, ²²²Rn) along with metals (e.g. Hg, Cd, Zn, Al) and particulate matter into the environment. We test the hypothesis whether chronic exposure to this specific type of pollution causes epithelial morphometric, mucosecretory and neuronal alterations on the nasal cavity. Thickness measurements were taken in the squamous, respiratory and olfactory epithelia. The relative density of cell types (basal, support and neurons) was also assessed in the olfactory epithelium and the mucosecretory activity was determined in the lateral nasal glands, Bowman’s gland and goblet cells. Mice chronically exposed to hydrothermal emissions presented thinner olfactory epithelia and lesser mucous production, which could result in loss of olfactory capabilities as well as a decrease in the protective function provided by the mucous to the lower respiratory tract. For the first time, it is demonstrated that, in mice, this specific type of non-eruptive active volcanism causes epithelial and mucosecretory alterations, leading to the loss of olfactory capabilities.
- 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.
- First record on mercury accumulation in mice brain living in active volcanic environments : a cytochemical approachPublication . Navarro-Sempere, Alicia; Segovia, Yolanda; Rodrigues, Armindo; Garcia, Patrícia; Camarinho, Ricardo; García, M.The health effects of mercury vapor exposure on the brain in volcanic areas have not been previously addressed in the literature. However, 10% of the worldwide population inhabits in the vicinity of an active volcano, which are natural sources of elemental mercury emission. To evaluate the presence of mercury compounds in the brain after chronic exposure to volcanogenic mercury vapor, a histochemical study, using autometallographic silver, was carried out to compare the brain of mice chronically exposed to an active volcanic environment (Furnas village, Azores, Portugal) with those not exposed (Rabo de Peixe village, Azores, Portugal). Results demonstrated several mercury deposits in blood vessels, white matter and some cells of the hippocampus in the brain of chronically exposed mice. Our results highlight that chronic exposure to an active volcanic environment results in brain mercury accumulation, raising an alert regarding potential human health risks. These findings support the hypothesis that mercury exposure can be a risk factor in causing neurodegenerative diseases in the inhabitants of volcanically active areas.
- First report on the prevalence of Klossiella muris in Mus musculus for S. Miguel Island : Azores (Portugal)Publication . Camarinho, Ricardo; Garcia, Patrícia; Mendonça, A. C.; Rodrigues, ArmindoKlossiella is a genus of apicomplexan coccidian parasites with a global distribution, whose members typically infect the renal tissue of a wide variety of vertebrate hosts with a high level of host specificity. The presence of this parasite has been previously associated with kidney inflammatory processes. To our knowledge, this is the first report on the prevalence of Klossiella muris in the house mouse (Mus musculus) in Portugal (São Miguel Island – Azores). The prevalence of K. muris was determined through histopathological examination of renal tissue collected during necropsy of 130 mice captured between the years of 2011–2019. K. muris was diagnosed in 45.38% (CI95: 40.9–85.4) of the examined mice. Infection with this parasite was associated with mild to severe kidney inflammation, assessed by the presence of inflammatory processes in the renal cortex and medulla. Capsule First record on coccidiosis caused by infection of Klossiella muris in Mus musculus in Portugal.
- The Health Hazards of Volcanoes : First Evidence of Neuroinflammation in the Hippocampus of Mice Exposed to Active Volcanic SurroundingsPublication . Navarro-Sempere, Alicia; Martínez-Peinado, Pascual; Rodrigues, Armindo; Garcia, Patrícia; Camarinho, Ricardo; García, Magdalena; Segovia, YolandaNeuroinflammation is a process related to the onset of neurodegenerative diseases; one of the hallmarks of this process is microglial reactivation and the secretion by these cells of proinflammatory cytokines such as TNFα. Numerous studies report the relationship between neuroinflammatory processes and exposure to anthropogenic air pollutants, but few refer to natural pollutants. Volcanoes are highly inhabited natural sources of environmental pollution that induce changes in the nervous system, such as reactive astrogliosis or the blood-brain barrier breakdown in exposed individuals; however, no neuroinflammatory event has been yet defined. To this purpose, we studied resting microglia, reactive microglia, and TNFα production in the brains of mice chronically exposed to an active volcanic environment on the island of São Miguel (Azores, Portugal). For the first time, we demonstrate a proliferation of microglial cells and an increase in reactive microglia, as well an increase in TNFα secretion, in the central nervous system of individuals exposed to volcanogenic pollutants.
- Histological evidence of hypothyroidism in mice chronically exposed to conventional farmingPublication . Coelho, Nádia; Camarinho, Ricardo; Garcia, Patrícia; Rodrigues, ArmindoWorldwide, disorders of the thyroid gland are a growing concern; such can be caused by exposure to contaminants, including agrochemicals used in conventional agriculture, which act as endocrine disruptors. The purpose of this study is to evaluate whether or not exposure to an environment with conventional agriculture leads to thyroid disruption. Mus musculus were used as bioindicator species, captured in two sites: a farm where conventional agriculture is practiced, and a place without agriculture. Thyroid histomorphometric and morphologic data were analyzed. The impacts of the agricultural environment over the thyroid were revealed, as indications of hypothyroidism were observed in exposed mice: the area and volume of epithelial cells were much lower. Alterations in thyroid histomorphology were also observed: lower follicular sphericity, irregularly delimited epithelium and increased exfoliation into the colloid. These results highlight the need for transition from current conventional agricultural systems towards organic systems.
- Leptospirose: o inimigo invisívelPublication . Camarinho, Ricardo; Rodrigues, ArmindoA leptospirose (também chamada doença de Weil) é uma zoonose bacteriana causada por espiroquetas patogénicas do género Leptospira. É uma doença com elevado impacto global que infecta humanos e animais. Relativamente ao impacto humano, estima-se que esta zoonose seja mundialmente responsável por cerca de 1 milhão de casos anuais, causando cerca de 60.000 mortes. A infeção pode ocorrer diretamente através de contacto com urina ou tecidos de animais contaminados, ou indiretamente através de exposição a água ou solos contaminados. Os principais reservatórios desta bactéria são os roedores, podendo outros mamíferos (como suínos e bovinos) excretar este agente pela urina durante meses ou anos. A sintomatologia desta doença é variada, e nos humanos poderá ir de sintomas de gripe a estado febril, diarreia, vómitos, mialgia e eventual morte do indivíduo, dificultando o diagnostico prévio. Em animais, como por exemplo os bovinos, de entre algumas das consequências da infeção destacam-se o aumento da taxa de aborto espontâneo, baixo-peso à nascença, quebra de produção de leite e, no limite, a morte.
- 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.