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1.
J Neurosci ; 43(1): 14-27, 2023 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-36384682

RESUMO

In the neocortex, fast synaptic inhibition orchestrates both spontaneous and sensory-evoked activity. GABAergic interneurons (INs) inhibit pyramidal neurons (PNs) directly, modulating their output activity and thus contributing to balance cortical networks. Moreover, several IN subtypes also inhibit other INs, forming specific disinhibitory circuits, which play crucial roles in several cognitive functions. Here, we studied a subpopulation of somatostatin-positive INs, the Martinotti cells (MCs) in layer 2/3 of the mouse barrel cortex (both sexes). MCs inhibit the distal portion of PN apical dendrites, thus controlling dendrite electrogenesis and synaptic integration. Yet, it is poorly understood whether MCs inhibit other elements of the cortical circuits, and the connectivity properties with non-PN targets are unknown. We found that MCs have a strong preference for PN dendrites, but they also considerably connect with parvalbumin-positive, vasoactive intestinal peptide-expressing, and layer 1 (L1) INs. Remarkably, GABAergic synapses from MCs exhibited clear cell type-specific short-term plasticity. Moreover, whereas the biophysical properties of MC-PN synapses were consistent with distal dendritic inhibition, MC-IN synapses exhibited characteristics of fast perisomatic inhibition. Finally, MC-PN connections used α5-containing GABAA receptors (GABAARs), but this subunit was not expressed by the other INs targeted by MCs. We reveal a specialized connectivity blueprint of MCs within different elements of superficial cortical layers. In addition, our results identify α5-GABAARs as the molecular fingerprint of MC-PN dendritic inhibition. This is of critical importance, given the role of α5-GABAARs in cognitive performance and their involvement in several brain diseases.SIGNIFICANCE STATEMENT Martinotti cells (MCs) are a prominent, broad subclass of somatostatin-expressing GABAergic interneurons, specialized in controlling distal dendrites of pyramidal neurons (PNs) and taking part in several cognitive functions. Here we characterize the connectivity pattern of MCs with other interneurons in the superficial layers (L1 and L2/3) of the mouse barrel cortex. We found that the connectivity pattern of MCs with PNs as well as parvalbumin, vasoactive intestinal peptide, and L1 interneurons exhibit target-specific plasticity and biophysical properties. The specificity of α5-GABAARs at MC-PN synapses and the lack or functional expression of this subunit by other cell types define the molecular identity of MC-PN connections and the exclusive involvement of this inhibitory circuits in α5-dependent cognitive tasks.


Assuntos
Parvalbuminas , Peptídeo Intestinal Vasoativo , Feminino , Masculino , Animais , Peptídeo Intestinal Vasoativo/metabolismo , Parvalbuminas/metabolismo , Neurônios , Células Piramidais/fisiologia , Interneurônios/fisiologia , Somatostatina/metabolismo , Sinapses/fisiologia , Ácido gama-Aminobutírico/metabolismo
2.
Artigo em Inglês | MEDLINE | ID: mdl-38516875

RESUMO

Dear Editor, According to GINA, severe asthma is defined as uncontrolled asthma, despite therapy adherence with an optimized high dose of inhaled corticosteroid plus long-acting ß2-agonist coupled with management of modifiable factors/comorbidities, that worsens when this treatment is decreased. It affects a significant portion of asthmatic patients and imposes a high risk of exacerbations and mortality, which are associated with significant healthcare costs and psychosocial impact...

3.
Anal Bioanal Chem ; 415(13): 2613-2627, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36631573

RESUMO

Microbial metabolomics allows understanding and to comprehensively analyse metabolites, and their related cellular and metabolic processes, that are produced and released to the extracellular environment under specific conditions. In that regard, the main objective of this research is to understand the impact of culture media changes in the metabolic profile of Pedobacter lusitanus NL19 (NL19) and Pedobacter himalayensis MTCC 6384 (MTCC6384) and respective influence on the production of biotechnologically relevant compounds. Solid-phase microextraction combined with comprehensive two-dimensional gas chromatography coupled to time-of-flight mass spectrometry with time-of-flight analyser (GC × GC-ToFMS) was applied to comprehensively study the metabolites produced by NL19 and MTCC6384 both in tryptic soy broth 100% (TSB100) and tryptic soy broth with 25% casein peptone (PC25). A total of 320 metabolites were putatively identified, which belong to different chemical families: alcohols, aldehydes, esters, ethers, hydrocarbons, ketones, nitrogen compounds, sulphur compounds, monoterpenes, and sesquiterpenes. Metabolites that were statistically different from the control (sterile medium) were selected allowing for the construction of the metabolic profile of both strains. A set of 80 metabolites was tentatively associated to the metabolic pathways such as the metabolism of fatty acids, branched-chain aminoacids, phenylalanine, methionine, aromatic compounds, and monoterpene and sesquiterpene biosynthesis. This study allowed to better understand how slight changes of the culture media and thus the composition of nutrients impair the metabolic profile of bacteria, which may be further explored for metabolomics pipeline construction or biotechnological applications.


Assuntos
Aldeídos , Compostos Orgânicos Voláteis , Humanos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Espectrometria de Massas , Monoterpenos , Meios de Cultura , Compostos Orgânicos Voláteis/química , Microextração em Fase Sólida/métodos
4.
PLoS Biol ; 17(9): e3000419, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31483783

RESUMO

Parvalbumin (PV)-positive interneurons modulate cortical activity through highly specialized connectivity patterns onto excitatory pyramidal neurons (PNs) and other inhibitory cells. PV cells are autoconnected through powerful autapses, but the contribution of this form of fast disinhibition to cortical function is unknown. We found that autaptic transmission represents the most powerful inhibitory input of PV cells in neocortical layer V. Autaptic strength was greater than synaptic strength onto PNs as a result of a larger quantal size, whereas autaptic and heterosynaptic PV-PV synapses differed in the number of release sites. Overall, single-axon autaptic transmission contributed to approximately 40% of the global inhibition (mostly perisomatic) that PV interneurons received. The strength of autaptic transmission modulated the coupling of PV-cell firing with optogenetically induced γ-oscillations, preventing high-frequency bursts of spikes. Autaptic self-inhibition represents an exceptionally large and fast disinhibitory mechanism, favoring synchronization of PV-cell firing during cognitive-relevant cortical network activity.


Assuntos
Interneurônios/fisiologia , Neocórtex/fisiologia , Sinapses , Transmissão Sináptica , Animais , Feminino , Masculino , Camundongos Endogâmicos C57BL
5.
World J Microbiol Biotechnol ; 38(1): 18, 2022 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-34977979

RESUMO

Lantibiotics are a promising class of natural antimicrobial peptides. Lichenicidin is a two-peptide lantibiotic in which two mature peptides act synergistically to exhibit full bioactivity. Considering the two-peptide lantibiotics described so far, only cytolysin has been deeply characterized in terms of toxicity towards eukaryotic cells and it was found to be hemolytic and cytotoxic. This work aimed to improve the production of lichenicidin in vivo and characterize its antibacterial activity and toxicity against human cells. Peptides were purified and minimal inhibitory concentration (MIC) was determined against several strains; a time-kill assay was performed with Staphylococcus aureus. The hemolytic effect of lichenicidin was evaluated on blood samples from healthy donors and its toxicity towards human fibroblasts. The quantity of purified peptides was 1 mg/l Bliα and 0.4 mg/l Bliß. MIC for methicillin-sensitive and resistant S. aureus (MSSA and MRSA) strains were 16-32 µg/ml and 64-128 µg/ml, respectively. At the MIC, lichenicidin took less than 3 h to eliminate MSSA, indicating a strong bactericidal effect. It induces cell lysis at the highest concentration, an effect that might be potentiated by Bliß. Lichenicidin was not cytotoxic to human erythrocytes and fibroblasts. In this work, we evaluated the therapeutic potential of lichenicidin as a possible antimicrobial alternative.


Assuntos
Anti-Infecciosos/farmacologia , Peptídeos Antimicrobianos/farmacologia , Bactérias/efeitos dos fármacos , Infecções Bacterianas/tratamento farmacológico , Bacteriocinas/farmacologia , Fibroblastos/efeitos dos fármacos , Peptídeos/farmacologia , Sequência de Aminoácidos , Anti-Infecciosos/química , Anti-Infecciosos/isolamento & purificação , Peptídeos Antimicrobianos/isolamento & purificação , Bacteriocinas/química , Bacteriocinas/isolamento & purificação , Linhagem Celular , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Hemólise , Humanos , Testes de Sensibilidade Microbiana
6.
Fam Pract ; 38(5): 606-611, 2021 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-33738481

RESUMO

BACKGROUND: Empathy is the capacity to understand and resonate with the experiences of other people. Patient enablement is the degree to which a patient feels strengthened in terms of being able to deal with, understand and manage their disease. METHODS: Secondary cross-sectional analysis of existing data from 2 independent datasets (456 primary health care patients), with the application of two validated questionnaires, Jefferson Scale of Patient Perceptions of Physician Empathy (JSPPPE) and Patient Enablement Instrument (PEI). OBJECTIVE: Evaluate medical empathy and patients' enablement after consultation with their family doctors and to verify if there was an association between these two concepts. RESULTS: The median value of JSPPPE-VP score was 6.60 (interquartile range 1.00) and of PEI/ICC score was of 1.83 (interquartile range 0.67). Regarding empathy (JSPPPE-VP), patients taking chronic medication had a slight but significantly higher median score than patients not taking them (6.70 versus 6.60, P = 0.049), although regression modelling did not confirm any relevant predictor of JSPPPE-VP score. Regarding enablement (PEI/ICC), we found significantly higher scores on younger patients, as well as, on more educated and professionally active ones (P < 0.001). Multivariable linear regression and Poisson regression modelling confirmed such variables as statistically significant potential predictors. CONCLUSIONS: A significant positive association was found between empathy score (JSPPPE-VP) and enablement score (PEI/ICC), when adjusted to sociodemographic cofactors. On this linear regression model, age category and educational level were also significantly associated with empathy score, with the same pattern found on bivariate analysis.


Assuntos
Empatia , Médicos , Estudos Transversais , Humanos , Satisfação do Paciente , Relações Médico-Paciente , Portugal , Atenção Primária à Saúde , Inquéritos e Questionários
7.
PLoS Biol ; 15(1): e2001378, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-28103228

RESUMO

One outstanding difference between Homo sapiens and other mammals is the ability to perform highly complex cognitive tasks and behaviors, such as language, abstract thinking, and cultural diversity. How is this accomplished? According to one prominent theory, cognitive complexity is proportional to the repetition of specific computational modules over a large surface expansion of the cerebral cortex (neocortex). However, the human neocortex was shown to also possess unique features at the cellular and synaptic levels, raising the possibility that expanding the computational module is not the only mechanism underlying complex thinking. In a study published in PLOS Biology, Szegedi and colleagues analyzed a specific cortical circuit from live postoperative human tissue, showing that human-specific, very powerful excitatory connections between principal pyramidal neurons and inhibitory neurons are highly plastic. This suggests that exclusive plasticity of specific microcircuits might be considered among the mechanisms endowing the human neocortex with the ability to perform highly complex cognitive tasks.


Assuntos
Córtex Cerebral/fisiologia , Rede Nervosa/fisiologia , Plasticidade Neuronal/fisiologia , Sinapses/fisiologia , Animais , Potenciais Pós-Sinápticos Excitadores/fisiologia , Humanos , Interneurônios/fisiologia , Camundongos , Tamanho do Órgão , Especificidade da Espécie
8.
Artigo em Inglês | MEDLINE | ID: mdl-32238096

RESUMO

This work presents the health-care waste (HCW) management and an approach to assess and identify polymers in a General Surgery Unit - Internment Service (GSU) of a Brazilian university hospital, to estimate the main polymers presenting in medical devices that are consumed during a year, discarded either as infecting (Group A) or as scarifying residue (Group E). Among the waste produced from the medical devices, 3.14 ton (98.79%) were composed of polymers (63.06% of plastics and 35.73% elastomers) while around 0.03 ton (1.21%) by metals. The proposed approach is composed of 4 steps: (1) Collecting data about consumed medical devices to be categorized into the residues Groups (A and E); (2) Identifying the polymeric composition with information provided by suppliers; (3) Characterizing the polymer functional groups by Fourier-Transform Infrared Spectroscopy (FTIR) and (4) Determining the polymer melting point by Differential Scanning Calorimetry (DSC). According to the results, the analyzed HCW was composed mainly of polypropylene (80.88%), high-density polyethylene (5.28%), polystyrene (4.51%), and cellulose (3.58%), from a total of 11 different polymers.


Assuntos
Eliminação de Resíduos de Serviços de Saúde/métodos , Polímeros/análise , Gerenciamento de Resíduos/métodos , Brasil , Celulose/análise , Hospitais de Ensino , Polietileno/análise , Poliestirenos/análise , Espectroscopia de Infravermelho com Transformada de Fourier
9.
PLoS Biol ; 12(7): e1001903, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25003184

RESUMO

In the neocortex, the coexistence of temporally locked excitation and inhibition governs complex network activity underlying cognitive functions, and is believed to be altered in several brain diseases. Here we show that this equilibrium can be unlocked by increased activity of layer 5 pyramidal neurons of the mouse neocortex. Somatic depolarization or short bursts of action potentials of layer 5 pyramidal neurons induced a selective long-term potentiation of GABAergic synapses (LTPi) without affecting glutamatergic inputs. Remarkably, LTPi was selective for perisomatic inhibition from parvalbumin basket cells, leaving dendritic inhibition intact. It relied on retrograde signaling of nitric oxide, which persistently altered presynaptic GABA release and diffused to inhibitory synapses impinging on adjacent pyramidal neurons. LTPi reduced the time window of synaptic summation and increased the temporal precision of spike generation. Thus, increases in single cortical pyramidal neuron activity can induce an interneuron-selective GABAergic plasticity effectively altering the computation of temporally coded information.


Assuntos
Células Piramidais/fisiologia , Potenciais de Ação/fisiologia , Animais , Canais de Cálcio Tipo L/fisiologia , Potenciação de Longa Duração/fisiologia , Depressão Sináptica de Longo Prazo/fisiologia , Camundongos Endogâmicos C57BL , Neocórtex/citologia , Plasticidade Neuronal/fisiologia , Neurônios , Técnicas de Patch-Clamp , Ácido gama-Aminobutírico/fisiologia
10.
Ecotoxicol Environ Saf ; 140: 198-205, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28260685

RESUMO

In the past few years the number of studies on the toxic effects of nanomaterials (NMs) in the environment increased significantly. Nonetheless, the data is still scarce, since there is a large number of NMs and new ones are being developed each day. Soils are extremely important for life, and are easily exposed to the released NMs, thus enhanced efforts are needed to study the impacts on soil biota. The objective of the present work was to determine if different concentrations of two NMs, one inorganic (TiSiO4) and other organic (nano-vesicles of sodium sodecyl sulfate/ didodecyl dimethylammonium bromide - SDS/DDAB), are genotoxic to soil invertebrates. Additionally, it was intended to understand whether, in the event of occurring, genotoxicity was caused by the incapability of the cells to deal with the oxidative stress caused by these NMs. With that purpose, Eisenia andrei were exposed for 30 days to the artificial OECD soil contaminated with different concentrations of the NMs being tested. After the exposure, coelomocytes were extracted from earthworms and DNA damage was measured by the comet assay. The activity of antioxidant enzymes (e.g. glutathione peroxidase, glutathione reductase and glutathione-S-Transferase) and lipid peroxidation were also assessed. The results showed that both NMs were genotoxic, particularly TiSiO4 for which significant DNA damages were recorded for concentrations above 444mg of TiSiO4-NM/kg of soildw. Since no statistically significant differences were found in the tested antioxidant enzymes and in lipid peroxidation, the mechanism of genotoxicity of these NMs seemed to be unrelated with oxidative stress.


Assuntos
Nanoestruturas/toxicidade , Oligoquetos/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Animais , Antioxidantes/metabolismo , Biota , Ensaio Cometa/métodos , Dano ao DNA/efeitos dos fármacos , Dano ao DNA/fisiologia , Glutationa Peroxidase/metabolismo , Peroxidação de Lipídeos/fisiologia , Compostos de Amônio Quaternário/toxicidade , Dióxido de Silício/toxicidade , Dodecilsulfato de Sódio/toxicidade , Solo/química , Poluentes do Solo/toxicidade , Titânio/toxicidade
11.
Zygote ; 25(3): 383-389, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28592345

RESUMO

The exposure of oocytes to heat stress during the maturation process results in harmful effects to their internal organelles, low fertilization capability and higher embryonic losses. In the present experiment the effect of heat shock (HS) during the maturation process was assessed. In Assay 1, oocytes from winter (December-March; n = 100) and summer (June-September; n = 100) months were collected and matured to analyse their HS tolerance. Total RNA was extracted from matured oocytes and cDNA synthesis was performed, followed by qPCR for selected genes (Cx43, CDH1, DNMT1, HSPA14), compared with two reference genes (GAPDH and SDHA). In Assay 2, oocytes collected during the winter were subjected to kinetic HS by stressing them at 39.5°C for 6, 12, 18 or 24 h and were afterwards matured at control temperature (38.5°C), and subsequently subjected to the previously described gene analysis procedure. Results of Assay 1 show that summer-collected oocytes exhibited lower maturation rate than winter-collected oocytes, which may be due to the down-regulation of the HSPA 14 gene. Assay 2 showed that 6 h of HS had no effect on gene regulation. CDH1 and DNMT1 up-regulation was observed starting at 12 h, which may represent the effect of heat shock on oocyte development.


Assuntos
Regulação da Expressão Gênica , Resposta ao Choque Térmico , Oócitos/fisiologia , Animais , Caderinas/genética , Bovinos , Conexina 43/genética , DNA (Citosina-5-)-Metiltransferase 1/genética , Feminino , Proteínas de Choque Térmico HSP70/genética , Técnicas de Maturação in Vitro de Oócitos/métodos , Estações do Ano
12.
Trends Genet ; 29(10): 559-60, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23998809

RESUMO

Understanding the genetic basis of human longevity remains a challenge but could lead to life-extending interventions and better treatments for age-related diseases. Toward this end we developed the LongevityMap (http://genomics.senescence.info/longevity/), the first database of genes, loci, and variants studied in the context of human longevity and healthy ageing. We describe here its content and interface, and discuss how it can help to unravel the genetics of human longevity.


Assuntos
Bases de Dados Genéticas , Variação Genética , Longevidade/genética , Sequência de Bases , Humanos , Dados de Sequência Molecular
13.
Zygote ; 24(5): 748-59, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27019120

RESUMO

Three assays were performed. In assay 1, oocytes harvested during the winter months were subjected to kinetic heat shock by stressing the oocytes at 39.5°C (HS1) or at 40.5°C (HS2) for either 6, 12, 18 or 24 h and then matured at control temperature (38.5°C). The nuclear maturation rates (NMR) of all oocytes were recorded after 24 h. In assay 2, oocytes collected year-round maturated, were implanted via in vitro fertilization (IVF) and developed for 9 days. Gene expression analysis was performed on target genes (Cx43, CDH1, DNMT1, HSPA14) with reference to the two housekeeping genes (GAPDH and SDHA) in embryos. Similarly, in assay 3, genetic analysis was performed on the embryos produced from heat-stressed oocytes (from HS1 and HS2). In assay 1, the duration of heat stress resulted in a significant decline in NMR (P < 0.05) with HS1 for maturated oocytes at 86.4 ± 4.3; 65.5 ± 0.7; 51.3 ± 0.9; 38.1 ± 1.9 and 36.3 ± 0.9, for control, 6 h, 12 h, 18 h and 24 h, respectively. For assays 2 and 3, results demonstrated that DNMT1, Cx43 and HSPA14 were down-regulated in the embryos produced in the warm with respect to the cold months (P < 0.05). A constant up- and down-regulation of DNMT1 and HSPA14 genes were observed in both HS-treated samples. Also, an inconsistent pattern of gene expression was observed in Cx43 and CDH1 genes (P < 0.05). Targeted gene expression was aberrant in embryo development, which can provide evidence on early embryo arrest and slowed embryo development.


Assuntos
Blastocisto/fisiologia , Regulação da Expressão Gênica no Desenvolvimento , Resposta ao Choque Térmico/fisiologia , Técnicas de Maturação in Vitro de Oócitos/métodos , Oócitos/fisiologia , Animais , Caderinas/genética , Bovinos , Conexina 43/genética , DNA (Citosina-5-)-Metiltransferases/genética , Feminino , Fertilização in vitro , Proteínas de Choque Térmico HSP70/genética , Masculino , Mórula/fisiologia , Estações do Ano
14.
Ecotoxicol Environ Saf ; 115: 279-90, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25733076

RESUMO

In the environment, chemical substances appear as complex mixtures and consequently organisms are exposed to a variety of chemicals from different sources (e.g. wastewater treatment plants, agriculture runoffs). When studying chemical mixtures, there are two conceptual models usually used to predict toxicity: the Independent Action (IA) and Concentration Addition (CA) models. However, deviations from these reference models can occur as synergism or antagonism, dose ratio or dose level dependency. The aim of the present study was to investigate the effects of triclosan and carbendazim, and their binary mixture to Daphnia magna. With this purpose, immobilisation, feeding inhibition, and reproduction were assessed as main ecotoxicity endpoints. In addition, in vivo genotoxicity of both chemicals was investigated using the comet assay. In the single exposure, carbendazim was more toxic to D. magna than triclosan. When daphnids were exposed to both single compounds, DNA damage was observed. Concerning mixture exposures, different endpoints followed different patterns of response, from additivity: IA model (feeding inhibition and reproduction data), to deviations that indicate interaction between chemicals inside the organism: dose level dependency (immobilisation data) and dose ratio dependency (DNA damage). This study showed that additivity does not rule the dose-effect relation in chemical mixtures of carbendazim and triclosan and interactions between both chemicals might induce generally higher toxicity than predicted based on single chemical exposures.


Assuntos
Benzimidazóis/toxicidade , Carbamatos/toxicidade , Dano ao DNA , Triclosan/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Daphnia/efeitos dos fármacos , Interações Medicamentosas , Reprodução/efeitos dos fármacos
15.
bioRxiv ; 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-39026855

RESUMO

In the mammalian neocortex, GABAergic interneurons (INs) inhibit cortical networks in profoundly different ways. The extent to which this depends on how different INs process excitatory signals along their dendrites is poorly understood. Here, we reveal that the functional specialization of two major populations of cortical INs is determined by the unique association of different dendritic integration modes with distinct synaptic organization motifs. We found that somatostatin (SST)-INs exhibit NMDAR-dependent dendritic integration and uniform synapse density along the dendritic tree. In contrast, dendrites of parvalbumin (PV)-INs exhibit passive synaptic integration coupled with proximally enriched synaptic distributions. Theoretical analysis shows that these two dendritic configurations result in different strategies to optimize synaptic efficacy in thin dendritic structures. Yet, the two configurations lead to distinct temporal engagement of each IN during network activity. We confirmed these predictions with in vivo recordings of IN activity in the visual cortex of awake mice, revealing a rapid and linear recruitment of PV-INs as opposed to a long-lasting integrative activation of SST-INs. Our work reveals the existence of distinct dendritic strategies that confer distinct temporal representations for the two major classes of neocortical INs and thus dynamics of inhibition.

16.
Ecotoxicol Environ Saf ; 88: 16-25, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23164450

RESUMO

The effects of the exposure of earthworms (Eisenia andrei) to contaminated soil from an abandoned uranium mine, were assessed through gene expression profile evaluation by Suppression Subtractive Hybridization (SSH). Organisms were exposed in situ for 56 days, in containers placed both in a contaminated and in a non-contaminated site (reference). Organisms were sampled after 14 and 56 days of exposure. Results showed that the main physiological functions affected by the exposure to metals and radionuclides were: metabolism, oxireductase activity, redox homeostasis and response to chemical stimulus and stress. The relative expression of NADH dehydrogenase subunit 1 and elongation factor 1 alpha was also affected, since the genes encoding these enzymes were significantly up and down-regulated, after 14 and 56 days of exposure, respectively. Also, an EST with homology for SET oncogene was found to be up-regulated. To the best of our knowledge, this is the first time that this gene was identified in earthworms and thus, further studies are required, to clarify its involvement in the toxicity of metals and radionuclides. Considering the results herein presented, gene expression profiling proved to be a very useful tool to detect earthworms underlying responses to metals and radionuclides exposure, pointing out for the detection and development of potential new biomarkers.


Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Oligoquetos/efeitos dos fármacos , Poluentes do Solo/toxicidade , Urânio/toxicidade , Animais , Biomarcadores/metabolismo , Cálcio/metabolismo , Monitoramento Ambiental , Ativação Enzimática/efeitos dos fármacos , Homeostase/efeitos dos fármacos , Hibridização Genética , Análise em Microsséries , Nucleossomos/efeitos dos fármacos , Oligoquetos/genética , Oligoquetos/metabolismo , Oxirredução , Oxirredutases/metabolismo , Solo/química , Transcriptoma
17.
Microsc Microanal ; 19(5): 1131-40, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23931156

RESUMO

The toxicity of titanium dioxide nanoparticles (TIO2 NPs) and oxidative stress effects were studied in two freshwater fish species (Carassius auratus and Danio rerio) exposed for 21 days to different concentrations (0.01, 0.1, 1, 10, 100/mgL) of TiO2 NPs and to a control (tap water). Additional fish were transferred to clean water for 14 days to assess the ability to recover from exposure to TiO2 NPs. Activities of the enzyme glutathione-S-transferase (GST) and lipid peroxidation (LPO) (malondialdheyde) were measured as indicators of oxidative stress. Histological and ultra-structural changes in livers from both species of fish were evaluated by light and electron microscopy. Results show a general GST activity increase according to TiO2 NPs concentrations, which is in agreement with data from LPO. After 21 days, GST activities decreased possibly caused by suppression of GST synthesis as a result of severe stress. Histological and ultra-structural analysis of livers from exposed fish show degeneration of the hepatic tissue and alterations in hepatocytes such as glycogen depletion and an increase in lipofucsin lysosome-like granules. After a depuration period a partial recovery for biochemical markers and cells was observed. The results suggest that TiO2 promotes alterations in hepatic tissues compatible with oxidative stress.


Assuntos
Carpa Dourada/metabolismo , Fígado/efeitos dos fármacos , Fígado/patologia , Nanopartículas/toxicidade , Titânio/toxicidade , Peixe-Zebra/metabolismo , Animais , Poluentes Ambientais/metabolismo , Poluentes Ambientais/toxicidade , Glutationa Transferase/metabolismo , Hepatócitos/efeitos dos fármacos , Hepatócitos/ultraestrutura , Histocitoquímica , Fígado/metabolismo , Microscopia Eletrônica , Nanopartículas/metabolismo , Peroxidase/metabolismo , Titânio/metabolismo
18.
Artigo em Inglês | MEDLINE | ID: mdl-37372717

RESUMO

Musculoskeletal (MSK) injuries have a significant physical and psychological influence on an athlete's life. A systematic review of prospective cohort, cross-sectional, and case-control studies was undertaken in this study to analyze the association between MSK injuries with depressive symptoms in athletes. We searched on PubMed, Web of Science, and Scopus, with data inception to 15 February 2023. The methodological quality was assessed using the Newcastle-Ottawa Scale (NOS). Of the 3677 potential studies only nine were included. These studies showed a bidirectional association between MSK injuries and depressive symptoms. Athletes with MSK injuries had higher levels of depressive symptoms, which raises the likelihood of experiencing depression in the future. Women athletes had higher levels of depressive symptoms compared with men. The presence of depressive symptoms is a significant predictor of disability in athletes. Our findings suggest that coaches should be more aware of depressive symptoms, in order to prevent MSK injuries, and to monitor athletes following an MSK injury.


Assuntos
Traumatismos em Atletas , Doenças Musculoesqueléticas , Masculino , Humanos , Feminino , Depressão/epidemiologia , Estudos Prospectivos , Estudos Transversais , Atletas/psicologia , Traumatismos em Atletas/psicologia
19.
Children (Basel) ; 10(4)2023 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-37189992

RESUMO

This study's aim was two-fold: (i) to test the intra-session reliability of the one-leg balance activity test; and (ii) to assess the influence of age on reaction time (RT) and the differences between dominant and non-dominant feet. Fifty young soccer players with an average age of 12.4 ± 1.8 years were divided into two groups: younger soccer players (n = 26; 11.6 ± 0.9 years) and older soccer players (n = 24; 14.2 ± 0.8 years). Each group then completed four trials (two with each leg) of the one-leg balance activity (OLBA) to evaluate RT under a single-leg stance. Mean RT and the number of hits were calculated, and the best trial was also selected. T-tests and Pearson correlations were performed for statistical analysis. Values for RT were lower, and the number of hits was higher while standing on the non-dominant foot (p = 0.01). MANOVA revealed that the "Dominant Leg" factor did not affect the multivariate composite (Pillai Trace = 0.05; F(4, 43) = 0.565; p = 0.689; Partial ETA Squared = 0.050; Observed Power = 0.174). The "Age" factor did not present an effect on the multivariate composite (Pillai Trace = 0.104; F(4, 43) = 1.243; p = 0.307; Partial ETA Squared = 0.104; Observed Power = 0.355). The results of the present investigation demonstrate that RT may be lower while standing on the non-dominant foot.

20.
Environ Int ; 175: 107954, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37187003

RESUMO

Naturally occurring radioactive materials (NORM) contribute to the dose arising from radiation exposure for workers, public and non-human biota in different working and environmental conditions. Within the EURATOM Horizon 2020 RadoNorm project, work is ongoing to identify NORM exposure situations and scenarios in European countries and to collect qualitative and quantitative data of relevance for radiation protection. The data obtained will contribute to improved understanding of the extent of activities involving NORM, radionuclide behaviours and the associated radiation exposure, and will provide an insight into related scientific, practical and regulatory challenges. The development of a tiered methodology for identification of NORM exposure situations and complementary tools to support uniform data collection were the first activities in the mentioned project NORM work. While NORM identification methodology is given in Michalik et al., 2023, in this paper, the main details of tools for NORM data collection are presented and they are made publicly available. The tools are a series of NORM registers in Microsoft Excel form, that have been comprehensively designed to help (a) identify the main NORM issues of radiation protection concern at given exposure situations, (b) gain an overview of materials involved (i.e., raw materials, products, by-products, residues, effluents), c) collect qualitative and quantitative data on NORM, and (d) characterise multiple hazards exposure scenarios and make further steps towards development of an integrated risk and exposure dose assessment for workers, public and non-human biota. Furthermore, the NORM registers ensure standardised and unified characterisation of NORM situations in a manner that supports and complements the effective management and regulatory control of NORM processes, products and wastes, and related exposures to natural radiation worldwide.


Assuntos
Exposição à Radiação , Monitoramento de Radiação , Proteção Radiológica , Radioatividade , Radioisótopos/análise , Europa (Continente)
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