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Objective: To compare the clinical characteristics, treatments, and evolution of critical patients with COVID-19 pneumonia treated in intensive care units (ICU) after one year of pandemic. Methodology: Multicenter, prospective study, which included critical COVID-19 patients in 9 ICUs in northwestern Spain. The clinical characteristics, treatments, and evolution of patients admitted to the ICU during the months of March-April 2020 (period 1) were compared with patients admitted in January-February 2021 (period 2). Results: 337 patients were included (98 in period 1 and 239 in period 2). In period 2, fewer patients required invasive mechanical ventilation (IMV) (65% vs. 84%, P < .001), using high-flow nasal cannulas (CNAF) more frequently (70% vs. 7%, P < .001), ventilation non-invasive mechanical (NIMV) (40% vs. 14%, P < .001), corticosteroids (100% vs. 96%, P = .007) and prone position in both awake (42% vs. 28%, P = .012), and intubated patients (67% vs. 54%, P = .034). The days of IMV, ICU stay and hospital stay were lower in period 2. Mortality was similar in the two periods studied (16% vs. 17%). Conclusions: After one year of pandemic, we observed that in patients admitted to the ICU, CNAF, NIMV, use of the prone position, and corticosteroids have been used more frequently, reducing the number of patients in IMV, and the length of stay in the ICU and hospital stay. Mortality was similar in the two study periods.
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Cyanotoxins are secondary metabolites produced by cyanobacteria, of varied chemical nature and toxic effects. Although cyanobacteria thrive in all kinds of ecosystems on Earth even under very harsh conditions, current knowledge on cyanotoxin distribution is almost restricted to freshwaters from temperate latitudes. In this review, we bring to the forefront the presence of cyanotoxins in extreme environments. Cyanotoxins have been reported especially in polar deserts (both from the Arctic and Antarctica) and alkaline lakes, but also in hot deserts, hypersaline environments, and hot springs. Cyanotoxins detected in these ecosystems include neurotoxins-anatoxin-a, anatoxin-a (S), paralytic shellfish toxins, ß-methylaminopropionic acid, N-(2-aminoethyl) glycine and 2,4-diaminobutyric acid- and hepatotoxins -cylindrospermopsins, microcystins and nodularins-with microcystins being the most frequently reported. Toxin production there has been linked to at least eleven cyanobacterial genera yet only three of these (Arthrospira, Synechococcus and Oscillatoria) have been confirmed as producers in culture. Beyond a comprehensive analysis of cyanotoxin presence in each of the extreme environments, this review also identifies the main knowledge gaps to overcome (e.g., scarcity of isolates and -omics data, among others) toward an initial assessment of ecological and human health risks in these amazing ecosystems developing at the very edge of life.
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Toxinas Bacterianas/metabolismo , Toxinas Marinas/metabolismo , Microcistinas/metabolismo , Animales , Regiones Antárticas , Regiones Árticas , Cianobacterias/metabolismo , Toxinas de Cianobacterias , Ecología , Ecosistema , Ambientes Extremos , HumanosRESUMEN
Cercopithifilaria bainae and Cercopithifilaria grassii (Spirurida, Onchocercidae) are filarioids inhabiting the skin of dogs worldwide. The microfilariae of a third species namely, Cercopithifilaria sp. II sensu Otranto et al. 2013, have been morphologically and molecularly characterized but scientific knowledge of this parasite is minimal. The first case of infection of a red fox (Vulpes vulpes) with the filarioid Cercopithifilaria sp. II is herein described in Castro Marim, Portugal. Microfilariae from skin sediment of the fox's ear were morphological characterized, and the identification was confirmed molecularly in samples from skin sediment, skin samples, and from Rhipicephalus sanguineus group ticks collected from the animal (99% homology with Cercopithifilaria sp. II). Studies should evaluate if red foxes might play a role in the maintenance and distribution of Cercopithifilaria sp. II infection in dog populations.
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Zorros/parasitología , Enfermedades Cutáneas Parasitarias/parasitología , Infecciones por Spirurida/veterinaria , Espirúridos , Animales , Femenino , Portugal/epidemiología , Enfermedades Cutáneas Parasitarias/epidemiología , Especificidad de la Especie , Infecciones por Spirurida/epidemiología , Infecciones por Spirurida/parasitologíaRESUMEN
Planktonic Nostocales cyanobacteria represent a challenge for microbiological research because of the wide range of cyanotoxins that they synthesize and their invasive behavior, which is presumably enhanced by global warming. To gain insight into the phylogeography of potentially toxic Nostocales from Mediterranean Europe, 31 strains of Anabaena (Anabaena crassa, A. lemmermannii, A. mendotae, and A. planctonica), Aphanizomenon (Aphanizomenon gracile, A. ovalisporum), and Cylindrospermopsis raciborskii were isolated from 14 freshwater bodies in Spain and polyphasically analyzed for their phylogeography, cyanotoxin production, and the presence of cyanotoxin biosynthesis genes. The potent cytotoxin cylindrospermopsin (CYN) was produced by all 6 Aphanizomenon ovalisporum strains at high levels (5.7 to 9.1 µg CYN mg(-1) [dry weight]) with low variation between strains (1.5 to 3.9-fold) and a marked extracellular release (19 to 41% dissolved CYN) during exponential growth. Paralytic shellfish poisoning (PSP) neurotoxins (saxitoxin, neosaxitoxin, and decarbamoylsaxitoxin) were detected in 2 Aphanizomenon gracile strains, both containing the sxtA gene. This gene was also amplified in non-PSP toxin-producing Aphanizomenon gracile and Aphanizomenon ovalisporum. Phylogenetic analyses supported the species identification and confirmed the high similarity of Spanish Anabaena and Aphanizomenon strains with other European strains. In contrast, Cylindrospermopsis raciborskii from Spain grouped together with American strains and was clearly separate from the rest of the European strains, raising questions about the current assumptions of the phylogeography and spreading routes of C. raciborskii. The present study confirms that the nostocalean genus Aphanizomenon is a major source of CYN and PSP toxins in Europe and demonstrates the presence of the sxtA gene in CYN-producing Aphanizomenon ovalisporum.
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Cianobacterias/clasificación , Cianobacterias/genética , Agua Dulce/microbiología , Toxinas Marinas/metabolismo , Filogeografía , Uracilo/análogos & derivados , Alcaloides , Toxinas Bacterianas , Cianobacterias/metabolismo , Toxinas de Cianobacterias , ADN Bacteriano/clasificación , ADN Bacteriano/genética , Datos de Secuencia Molecular , Análisis de Secuencia de ADN , España , Uracilo/metabolismoRESUMEN
Cyanobacteria inhabiting extreme environments constitute a promising source for natural products with biotechnological applications. However, they have not been studied in-depth for this purpose due to the difficulties in their isolation and mass culturing. The Atacama Desert suffers one of the highest solar irradiances that limits the presence of life on its hyperarid core to endolithic microbial communities supported by cyanobacteria as primary producers. Some of these cyanobacteria are known to produce scytonemin, a UV-screening liposoluble pigment with varied biotechnological applications in cosmetics and other industries. In this work we carried out a strain selection based on growth performance among 8 endolithic cyanobacteria of the genera Chroococcidiopsis, Gloeocapsa and Gloeocapsopsis isolated from non-saline rocks of the Atacama Desert. Then we investigated the influence of NaCl exposure on scytonemin production yield. Results in the selected strain (Chroococcidiopsis sp. UAM571) showed that rising concentrations of NaCl lead to a growth decrease while triggering a remarkable increase in the scytonemin content, reaching maximum values at 20 g L-1 of NaCl over 50-fold higher scytonemin contents than those obtained without NaCl. Altogether, these findings point out to cyanobacteria from the Atacama Desert as potentially suitable candidates for pilot-scale cultivation with biotechnological purposes, particularly to obtain scytonemin.
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Cianobacterias , Clima Desértico , Indoles , Salinidad , Cianobacterias/metabolismo , Cianobacterias/crecimiento & desarrollo , Indoles/metabolismo , Fenoles/metabolismoRESUMEN
In the last decade, over 40% of bird species in Europe have experienced poor and bad conservation status, with more than 30% of bird species in mainland Portugal threatened with extinction. Along with anthropogenic factors, parasites and pathogens such as avian haemosporidians have been suggested to be responsible for these avian population declines. Wildlife rehabilitation centres play an essential role in species conservation and preservation. Moreover, animals admitted for rehabilitation can provide valuable information regarding transmission and pathogenicity of many diseases that affect wild birds that are rarely sampled in nature. However, reports of haemosporidians in captive birds are still limited. Here, we explored the prevalence and genetic diversity of avian haemosporidians in 89 birds from 29 species admitted to rehabilitation centres in Portugal, showing an overall infection prevalence of 30.3%. The prevalence of infection was higher in Strigiformes and in birds admitted to rehabilitation centres due to debilitating diseases. Remarkably, 30% of the infected bird species have not been found to harbour malaria parasites in preceding studies. We detected 15 different haemosporidian lineages infecting a third of bird species sampled. Notably, 2 out of these 15 detected haemosporidian lineages have not been obtained previously in other studies. Furthermore, we also identified nine new host-parasite interactions representing new host records for these haemosporidian parasites. Finally, our results revealed that birds infected with haemosporidians require longer rehabilitation treatments, which increase the economic costs for rehabilitation and may impair their survival prospects. These findings emphasise the importance of integrating haemosporidian infection considerations into rehabilitation protocols, highlighting the challenges posed by these infections in avian conservation and rehabilitation, including economic and logistical demands.
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Polybrominated diphenyl ethers are persistent disrupters assimilated by organisms, yet little is known about their link to plastic ingestion and health effects. In an experiment, two groups of yellow-legged/lesser black-backed gulls (Larus michahellis/Larus fuscus) were fed plastics with BDE99 to assess leaching into brain, preen oil, liver and fat tissues and evaluate effects on health and stress parameters. Although most plastic was regurgitated, we observed a clear relation between plastic ingestion and chemical leaching. BDE99 exhibited higher levels in brain tissue of gulls from the plastic groups. Also, only values of cholinesterases measured in plasma were significantly reduced in the 'plastic' groups. Cholinesterase activity in the brain also tended to decrease, suggesting a negative effect in gulls' neurofunction. Results indicate that chemical leaching occurs, even when plastics stay in the stomach for a short period of time and showed that this can affect gulls' health.
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Charadriiformes , Animales , Éteres Difenilos Halogenados , HígadoRESUMEN
The western-European hedgehog (Erinaceus europaeus) is an insectivore with a wide distribution in Portugal and a potential tool for biomonitoring relevant One Health hazards, including heavy metal(loid)s' pollution. The aim of this study was to positively contribute to the current knowledge about the metal(loid) pollution in Portugal. Forty-six hedgehogs (from rescue centres; with known provenance) were necropsied. Sex, age category and weight were determined. Spines, liver and kidney were collected, and metalloid concentrations were determined by inductively coupled plasma mass spectrophotometry (ICP-MS). In general, results did not present alarming metal(loid) concentrations, with the exception of cadmium (Cd) (in the kidneys) and copper (Cu). Hedgehogs from Viana do Castelo and Viseu showed elevated concentrations of arsenic (As) and Castelo Branco presented concerning values of cadmium (Cd). Adult and heavier hedgehogs tended to present higher levels of metal(loid)s. Sex does not seem to significantly affect the metal(loid)s' concentrations. Further analysis would be needed to prioritize areas with detail and allow the application of the necessary mitigation strategies.
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Metaloides , Metales Pesados , Animales , Cadmio/análisis , Portugal , Erizos , Monitoreo del Ambiente/métodos , Metales Pesados/análisis , Metaloides/análisis , China , Medición de RiesgoRESUMEN
Avian Dicrocoeliidae are difficult to identify, even in their adult stages. Molecular analyses have been conducted for only a few species, complicating the accurate identification of juvenile stages. The taxonomy of the family is unresolved, and the status of many dicrocoeliid species is uncertain. Sequences of nuclear and mitochondrial DNA loci of Central European avian Dicrocoeliidae were generated and analyzed. These included representatives of the genera Lyperosomum, Platynosomum, Stromitrema, Brachylecithum, Brachydistomum, and Lutztrema. All the sequences were obtained from morphologically identified adult specimens of dicrocoeliids isolated from avian hosts. Molecular support was obtained to validate Lyperosomum turdia, confirm the rejection of Lyperosomum dujardini and Lyperosomum alagesi, and resurrect Lyperosomum longicauda and Lyperosomum collurionis. The identity of European Platynosomum illiciens from avian hosts with American vouchers of the same species from avian and mammalian hosts was confirmed. Brachylecithum fringillae is not considered valid; the individuals that matched its diagnosis were subadult Brachydistomum ventricosum. Descriptions and comparative data for five new species are provided. These are Lyperosomum hirundinis sp. n., Lyperosomum tenori sp. n., Lyperosomum atricapillae sp. n., Stromitrema acrocephali sp. n., and Lutztrema atricapillae sp. n.. Based on the molecular data, suggestions are provided regarding the validity of dicrocoeliid species that parasitize Central European birds. Further research should address the polyphyletic status of Brachylecithum.
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Due to poisoning and decline in the food resources of Eurasian vultures, there has been a rise in the number of Griffon (Gyps fulvus) and Cinereous vultures (Aegypius monachus) needing veterinary care. In captivity, vultures often develop oral and other infectious diseases which can affect their survival and the probability of reintroduction in the wild. Therefore, it is important to characterize relevant microbial species present in the oral cavity of vultures, such as Mucor spp. In this work, seven Mucor spp. isolates previously obtained from Gyps fulvus and Aegypius monachus oral swabs collected at two rehabilitation centers in Portugal were characterized regarding their pathogenic enzymatic profile and antimicrobial activity. Isolates were identified by macro and microscopic observation, and PCR and ITS sequencing. Their antimicrobial activity was determined using a collection of pathogenic bacteria and two yeast species. Results showed that 86% of the isolates produced α-hemolysis, 71% expressed DNase, 57% produce lecithinase and lipase, 29% expressed gelatinase, and 29% were biofilm producers. Four isolates showed inhibitory activity against relevant human and veterinary clinical isolates, including Escherichia coli, Enterococcus faecium, Neisseria zoodegmatis, and Staphylococcus aureus. In conclusion, accurate management programs should consider the benefits and disadvantages of Mucor spp. presence in the oral mucosa.
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Heavy metal(loid) pollution of ecosystems is a current One Health problem. The liver is one of the most affected organs in cases of acute or chronic exposure to abnormal amounts of these substances, inducing histopathologic lesions. In order to assess the influence of heavy metal(loids), forty-five European hedgehogs (Erinaceus europaeus) were submitted to necropsy, and liver samples were collected for a routine histopathology exam and metal(loid)s determination (As, Cd, Co, Cr, Cu and Pb) by ICP-MS. Age was estimated during the necropsy exam. Biliary hyperplasia was the most frequent lesion observed (16/45; 35.56%). No statistically significant associations were found between biliary hyperplasia and age or sex. Metal(loid)s' concentrations were higher in animals with biliary hyperplasia (except for As). There was a statistically significant difference for both Cd and Co. For As, Cd and Co, cubs and juveniles animals showed significantly lower concentrations than elder individuals. Only for Pb were significant differences found between females and males. As described in the literature, exposure to metal(loid)s may be a cause of biliary hyperplasia, although further research (including the use of biochemical methods) is needed to support these results. To the authors' knowledge, this is the first report of this association in hedgehogs.
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OBJECTIVE: To compare the clinical characteristics, treatments, and evolution of critical patients with COVID-19 pneumonia treated in Intensive Care Units (ICU) after one year of pandemic. METHODOLOGY: Multicenter, prospective study, which included critical COVID-19 patients in 9 ICUs in northwestern Spain. The clinical characteristics, treatments, and evolution of patients admitted to the ICU during the months of March-April 2020 (period 1) were compared with patients admitted in January-February 2021 (period 2). RESULTS: 337 patients were included (98 in period 1 and 239 in period 2). In period 2, fewer patients required invasive mechanical ventilation (IMV) (65% vs 84%, pâ¯<â¯0.001), using high-flow nasal cannulas (CNAF) more frequently (70% vs 7%, pâ¯<â¯0.001), ventilation non-invasive mechanical (NIMV) (40% vs 14%, pâ¯<â¯0.001), corticosteroids (100% vs 96%, pâ¯=â¯0.007) and prone position in both awake (42% vs 28%, pâ¯=â¯0.012), and intubated patients (67% vs 54%, pâ¯=â¯0.034). The days of IMV, ICU stay and hospital stay were lower in period 2. Mortality was similar in the two periods studied (16% vs 17%). CONCLUSIONS: After 1â¯year of pandemic, we observed that in patients admitted to the ICU, CNAF, NIMV, use of the prone position, and corticosteroids have been used more frequently, reducing the number of patients in IMV, and the length of stay in the ICU and hospital stay. Mortality was similar in the two study periods.
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COVID-19 , Humanos , COVID-19/epidemiología , COVID-19/terapia , Estudios Prospectivos , Pandemias , SARS-CoV-2 , Unidades de Cuidados IntensivosRESUMEN
In the context of detection of weeds in crops for site-specific weed control, on-ground spectral reflectance measurements are the first step to determine the potential of remote spectral data to classify weeds and crops. Field studies were conducted for four years at different locations in Spain. We aimed to distinguish cruciferous weeds in wheat and broad bean crops, using hyperspectral and multispectral readings in the visible and near-infrared spectrum. To identify differences in reflectance between cruciferous weeds, we applied three classification methods: stepwise discriminant (STEPDISC) analysis and two neural networks, specifically, multilayer perceptron (MLP) and radial basis function (RBF). Hyperspectral and multispectral signatures of cruciferous weeds, and wheat and broad bean crops can be classified using STEPDISC analysis, and MLP and RBF neural networks with different success, being the MLP model the most accurate with 100%, or higher than 98.1%, of classification performance for all the years. Classification accuracy from hyperspectral signatures was similar to that from multispectral and spectral indices, suggesting that little advantage would be obtained by using more expensive airborne hyperspectral imagery. Therefore, for next investigations, we recommend using multispectral remote imagery to explore whether they can potentially discriminate these weeds and crops.
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Algoritmos , Brassicaceae/anatomía & histología , Redes Neurales de la Computación , Reconocimiento de Normas Patrones Automatizadas/métodos , Malezas/anatomía & histología , Estaciones del Año , Análisis Espectral/métodos , Brassicaceae/fisiología , Análisis Discriminante , Malezas/fisiologíaRESUMEN
BACKGROUND: Parasitic conjunctivitis caused by Philophthalmus spp. is a common ophthalmic disease in birds, with localized outbreaks occurring worldwide. There is no consensus on treating this disease; mechanical removal is considered a standard recommendation, but is associated with disease relapses within days or weeks. METHODS: From 2015 to 2020, we examined 4295 Larus michahellis and Larus fuscus gulls in southern Portugal for the presence of Philophthalmus spp. Due to the need to treat dozens of infected gulls in the rescue station, we tested three treatment regimens aimed at targeting Philophthalmus lucipetus in the infected gulls: (I) the ophthalmic application of levamisole; (II) the oral application of milbemycin in combination with praziquantel; and (III) the subcutaneous application of ivermectin. RESULTS: The outbreak of philophthalmosis in gulls in southern Portugal has been ongoing since the first cases were reported in 2015-2016. The prevalence of philophthalmosis has fluctuated annually, peaking a maximum of 10.3% in L. fuscus in 2017 and at 2.1% in L. michahellis in 2016. The infection intensity peaked at a median of 11.5 eye-flukes per host bird in L. fuscus in 2016 and a median of six eye-flukes per host bird in L. michahellis in 2017. Nine gulls were infected with >50 eye-flukes. None of the treatment options were effective at treating P. lucipetus infections: the numbers of eye-flukes in the infected birds did not decrease, and the clinical signs of the disease did not change. CONCLUSIONS: An outbreak of philophthalmosis in southern Portugal has massively affected two species of gulls in the region. Two previously suggested philophthalmosis treatments (ocular levamisole and praziquantel given orally), as well as a third mode of treatment with a previously failed compound (ivermectin administered subcutaneously) were used. However, the treatments did not affect the numbers of P. lucipetus in the eyes of the treated gulls. Further research should address ophthalmic gel formulations or sub-conjunctival delivery mode for antihelminthic drugs that are effective against Philophthalmus spp. in vitro.
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Antihelmínticos , Charadriiformes , Trematodos , Infecciones por Trematodos , Animales , Antihelmínticos/uso terapéutico , Aves , Charadriiformes/parasitología , Brotes de Enfermedades , Ivermectina , Levamisol , Portugal/epidemiología , Praziquantel/uso terapéutico , Infecciones por Trematodos/parasitologíaRESUMEN
The cyanobacteria management in water bodies requires a deep knowledge of the community composition. Considering the reliable and thorough information provided by the polyphasic approach in cyanobacteria taxonomy, here we assess the cyanobacterial community structure of the Cheffia reservoir from Algeria. Cyanobacteria were identified on the basis of morphological traits and next-generation sequencing (NGS); toxins-related genes were localized in addition to the identification of toxins; temperature and nutrient level of water samples were also determined. The polyphasic approach was essential for cyanobacteria investigation; 28 genera were identified through 16S rRNA metabarcoding with the dominance of taxa from Microcystis (34.2%), Aphanizomenon (20.1%), and Planktothrix (20.0%), and morphological analysis revealed the association in this water body of five species within the genus Microcystis: M. aeruginosa, M. novacekii, M. panniformis, M. ichthyoblabe, and M. flos-aquae. The presence of mcyE genotypes was detected; moreover, HPLC-PDA and LC-ESI-MS/MS revealed the production of microcystin-LR. Results obtained in our study are very important since this ecosystem is used for water supply and irrigation; as a consequence, a good water management plan is essential.
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Cianobacterias , Microcystis , Argelia , Cianobacterias/química , Ecosistema , Monitoreo del Ambiente/métodos , Microcistinas/análisis , Microcystis/genética , ARN Ribosómico 16S/genética , Espectrometría de Masas en Tándem , Agua/análisisRESUMEN
Myxomatosis is an emergent disease in the Iberian hare (Lepus granatensis). In this species, the disease is caused by a natural recombinant virus (ha-myxoma virus [MYXV]) identified for the first time in 2018 and has since been responsible for a large number of outbreaks in Spain and Portugal. The ha-MYXV, which harbours a 2.8 Kb insert-disrupting gene M009L, can also infect and cause disease in wild and domestic rabbits, despite being less frequently identified in rabbits. During the laboratory investigations of wild leporids found dead in Portugal carried out within the scope of a Nacional Surveillance Plan (Dispatch 4757/17, MAFDR), co-infection events by classic (MYXV) and naturally recombinant (ha-MYXV) strains were detected in both one Iberian hare and one European wild rabbit (Oryctolagus cuniculus algirus). These two cases were initially detected by a multiplex qPCR detection of MYXV and ha-MYXV and subsequently confirmed by conventional PCR and sequencing of the M009L gene, which contains an ha-MYXV-specific insertion. To our knowledge, this is the first documented report of co-infection by classic MYXV and ha-MYXV strains either in Iberian hare or in European wild rabbit. It is also the first report of infection of an Iberian hare by a classic MYXV strain. These findings highlight the continuous evolution of the MYXV and the frequent host range changes that justify the nonstop monitoring of the sanitary condition of wild Leporidae populations in the Iberian Peninsula.
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Coinfección , Liebres , Myxoma virus , Animales , Coinfección/epidemiología , Coinfección/veterinaria , Especificidad del Huésped , Myxoma virus/genética , Filogenia , ConejosRESUMEN
Marine biotoxins have been frequently implicated in morbidity and mortality events in numerous species of birds worldwide. Nevertheless, their effects on seabirds have often been overlooked and the associated ecological impact has not been extensively studied. On top of that, the number of published studies confirming by analyses the presence of marine biotoxins from harmful algal blooms (HABs) in seabirds, although having increased in recent years, is still quite low. This review compiles information on studies evidencing the impact of HAB toxins on marine birds, with a special focus on the effects of paralytic and amnesic shellfish toxins (PSTs and ASTs). It is mainly centered on studies in which the presence of PSTs and/or ASTs in seabird samples was demonstrated through analyses. The analytical techniques commonly employed, the tissues selected and the adjustments done in protocols for processing seabird matrixes are summarized. Other topics covered include the role of different vectors in the seabird intoxications, information on clinical signs in birds affected by PSTs and ASTs, and multifactorial causes which could aggravate the syndromes. Close collaboration between seabird experts and marine biotoxins researchers is needed to identify and report the potential involvement of HABs and their toxins in the mortality events. Future studies on the PSTs and ASTs pharmacodynamics, together with the establishment of lethal doses in various seabird species, are also necessary. These studies would aid in the selection of the target organs for toxins analyses and in the postmortem intoxication diagnoses.
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Enfermedades de las Aves/prevención & control , Aves , Toxinas Marinas/toxicidad , Intoxicación por Mariscos/prevención & control , Animales , Humanos , Toxinas Marinas/análisis , Intoxicación por Mariscos/veterinariaRESUMEN
Microplastics (MPs) have been found everywhere as they are easily transported between environmental compartments. Through their transport, MPs are quickly colonized by microorganisms; this microbial community is known as the plastisphere. Here, we characterized the plastisphere of three MPs, one biodegradable (PHB) and two non-biodegradables (HDPE and LDPE), deployed in an Arctic freshwater lake for eleven days. The plastisphere was found to be complex, confirming that about a third of microbial colonizers were viable. Plastisphere was compared to microbial communities on the surrounding water and microbial mats on rocks at the bottom of the lake. Microbial mats followed by MPs showed the highest diversity regarding both prokaryotes and eukaryotes as compared to water samples; however, for fungi, MPs showed the highest diversity of the tested substrates. Significant differences on microbial assemblages on the three tested substrates were found; regarding microbial assemblages on MPs, bacterial genera found in polar environments such as Mycoplana, Erythromicrobium and Rhodoferax with species able to metabolize recalcitrant chemicals were abundant. Eukaryotic communities on MPs were characterized by the presence of ciliates of the genera Stentor, Vorticella and Uroleptus and the algae Cryptomonas, Chlamydomonas, Tetraselmis and Epipyxis. These ciliates normally feed on algae so that the complexity of these assemblages may serve to unravel trophic relationships between co-existing taxa. Regarding fungal communities on MPs, the most abundant genera were Betamyces, Cryptococcus, Arrhenia and Paranamyces. MPs, particularly HDPE, were enriched in the sulI and ermB antibiotic resistance genes (ARGs) which may raise concerns about human health-related issues as ARGs may be transferred horizontally between bacteria. This study highlights the importance of proper waste management and clean-up protocols to protect the environmental health of pristine environments such as polar regions in a context of global dissemination of MPs which may co-transport microorganisms, some of them including ARGs.
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Lagos , Microplásticos , Bacterias , Farmacorresistencia Microbiana , Humanos , Plásticos , ProhibitinasRESUMEN
Toxoplasma gondii is a worldwide zoonotic parasite. According to the "One Health" approach, studies on toxoplasmosis are essential since it affects humans and domestic and wild animals. In the present study, antibodies to T. gondii were determined in serum samples from 263 wild birds located in five wildlife rehabilitation centres in mainland Portugal by using the modified agglutination test (MAT) with a cut-off titre of 20. An overall seroprevalence of 36.5% (95% confidence interval [CI]: 30.7-42.6) was observed. For the first time, antibodies to T. gondii were detected in some avian species, including pallid swift (Apus pallidus) (33.3%), black-backed gull (Larus fuscus) (39.3%), European turtle-dove (Streptopelia turtur) (100%), bee-eater (Merops apiaster) (50.0%), carrion crow (Corvus corone) (33.3%), and Egyptian vulture (Neophron percnopterus) (100%), which expands the list of intermediate hosts of T. gondii. A lower seroprevalence was found in juvenile birds (31.9%) compared to adults (48.7%) (p = 0.016). The central region of Portugal was considered a risk factor for T. gondii infection in wild birds (odds ratio: 3.61; 95% CI: 1.09-11.91). This pioneer study calls attention to the need for further studies, to provide a clearer understanding of T. gondii epidemiology in Portugal, because it reflects wide dispersion of T. gondii oocysts in the environment.
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Cyanobacteria exposed to high solar radiation make use of a series of defense mechanisms, including avoidance, antioxidant systems, and the production of photoprotective compounds such as scytonemin. Two cyanobacterial strains of the genus Chroococcidiopsis from the Atacama Desert - which has one of the highest solar radiation levels on Earth- were examined to determine their capacity to protect themselves from direct photosynthetically active (PAR) and ultraviolet radiation (UVR): the UAM813 strain, originally isolated from a cryptoendolithic microhabitat within halite (NaCl), and UAM816 strain originally isolated from a chasmoendolithic microhabitat within calcite (CaCO3). The oxidative stress induced by exposure to PAR or UVR + PAR was determined to observe their short-term response, as were the long-term scytonemin production, changes in metabolic activity and ultrastructural damage induced. Both strains showed oxidative stress to both types of light radiation. The UAM813 strain showed a lower acclimation capacity than the UAM816 strain, showing an ever-increasing accumulation of reactive oxygen species (ROS) and a smaller accumulation of scytonemin. This would appear to reflect differences in the adaptation strategies followed to meet the demands of their different microhabitats.