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1.
Microorganisms ; 12(8)2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39203567

RESUMO

Staphylococcus aureus is a pathogen known to cause a wide range of infections. To find new targets for identification and to understand host-pathogen interactions, many studies have focused on surface proteins. We performed bacterial-cell surface-shaving, followed by tandem mass tag for quantitative mass spectrometry proteomics, to examine the surfaceome of S. aureus. Two steps were performed, the first step including surface protein-deficient mutants of S. aureus Newman strain lacking important virulence genes (clfA and spa, important for adhesion and immune evasion and srtAsrtB, linking surface-associated virulence factors to the surface) and the second step including isolates of different clinical origin. All strains were compared to the Newman strain. In Step 1, altogether, 7880 peptides were identified, corresponding to 1290 proteins. In Step 2, 4949 peptides were identified, corresponding to 919 proteins and for each strain, approximately 20 proteins showed differential expression compared to the Newman strain. The identified surface proteins were related to host-cell-adherence and immune-system-evasion, biofilm formation, and survival under harsh conditions. The results indicate that surface-shaving of intact S. aureus bacterial strains in combination with quantitative proteomics is a useful tool to distinguish differences in protein abundance of the surfaceome, including the expression of virulence factors.

2.
Sci Rep ; 13(1): 21862, 2023 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-38071200

RESUMO

This study aimed to analyse the knowledge of Portuguese physical education (PE) teachers according to the health recommendations for physical activity (PA) for children and adolescents. A total of 764 teachers participated (55.2% men) with a mean age of 48.2 years. Data was collected using answering to an online survey. Teachers were asked about PA's frequency, duration and intensity to achieve the recommended level PA. Chi-square was applied to analyse the associations. The main finding is that PE teachers have a lack of knowledge of the health recommendations of PA. Specifically, only 7.5% of the PE teachers in our study could identify the PA recommendations correctly. The intensity component in the health recommendation is the one in which most PE teachers demonstrate correct knowledge of (60.5%), with significant differences in gender and teaching level. However, significantly fewer PE teachers knew the frequency component in the health recommendations for PA (25%), with significant differences in education level. For the duration component, only 37.6% of teachers knew the recommendations. In light of our findings, it is a concern that PE teachers generally lack knowledge according to children's fulfilment of health recommendations for PA.


Assuntos
Exercício Físico , Educação Física e Treinamento , Masculino , Criança , Humanos , Adolescente , Pessoa de Meia-Idade , Feminino , Promoção da Saúde , Inquéritos e Questionários , Escolaridade , Instituições Acadêmicas
3.
Artigo em Inglês | MEDLINE | ID: mdl-36748493

RESUMO

Two Legionella-like strains isolated from hot water distribution systems in 2012 have been characterized phenotypically, biochemically and genomically in terms of DNA relatedness. Both strains, HCPI-6T and EUR-108, exhibited biochemical phenotypic profiles typical of Legionella species. Cells were Gram-negative motile rods which grew on BCYEα agar but not on blood agar and displayed phenotypic characteristics typical of the family Legionellaceae, including a requirement for l-cysteine and testing catalase positive. Both strains were negative for oxidase, urease, nitrate reduction and hippurate negative, and non-fermentative. The major ubiquinone was Q12 (59.4 % HCPI-6T) and the dominant fatty acids were C16 : 1 ω7c (28.4 % HCPI-6T, ≈16 % EUR-108), C16 : 0 iso (≈22.5 % and ≈13 %) and C15 : 0 anteiso (19.5 % and ≈23.5 %, respectively). The percent G+C content of genomic DNA was determined to be 39.3 mol %. The 16S rRNA gene, mip sequence and comparative genome sequence-based analyses (average nucleotide identity, ANI; digital DNA-DNA hybridization, dDDH; and phylogenomic treeing) demonstrated that the strains represent a new species of the genus Legionella. The analysis based on the 16S rRNA gene sequences showed that the sequence similarities for both strains ranged from 98.8-90.1 % to other members of the genus. The core genome-based phylogenomic tree (protein-concatemer tree based on concatenation of 418 proteins present in single copy) revealed that these two strains clearly form a separate cluster within the genus Legionella. ANI and dDDH values confirmed the distinctiveness of the strains. Based on the genomic, genotypic and phenotypic findings from a polyphasic study, the isolates are considered to represent a single novel species, for which the name Legionella maioricensis sp. nov. is proposed. The type strain is HCPI-6T (=CCUG 75071T=CECT 30569T).


Assuntos
Hospitais , Legionella , Filogenia , Microbiologia da Água , Abastecimento de Água , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
4.
Microbiol Spectr ; 11(1): e0386722, 2023 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-36622237

RESUMO

Resistance to ß-lactams is known to be multifactorial, although the underlying mechanisms are not well established. The aim of our study was to develop a system for assessing the phenotypic and proteomic responses of bacteria to antibiotic stress as a result of the loss of selected antimicrobial resistance genes. We applied homologous recombination to knock out plasmid-borne ß-lactamase genes (blaOXA-1, blaTEM-1, and blaCTX-M15) in Escherichia coli CCUG 73778, generating knockout clone variants lacking the respective deleted ß-lactamases. Quantitative proteomic analyses were performed on the knockout variants and the wild-type strain, using bottom-up liquid chromatography tandem mass spectrometry (LC-MS/MS), after exposure to different concentrations of cefadroxil. Loss of the blaCTX-M-15 gene had the greatest impact on the resulting protein expression dynamics, while losses of blaOXA-1 and blaTEM-1 affected fewer proteins' expression levels. Proteins involved in antibiotic resistance, cell membrane integrity, stress, and gene expression and unknown function proteins exhibited differential expression. The present study provides a framework for studying protein expression in response to antibiotic exposure and identifying the genomic, proteomic, and phenotypic impacts of resistance gene loss. IMPORTANCE The critical situation regarding antibiotic resistance requires a more in-depth effort for understanding underlying mechanisms involved in antibiotic resistance, beyond just detecting resistance genes. The methodology presented in this work provides a framework for knocking out selected resistance factors, to study the adjustments of the bacterium in response to a particular antibiotic stress, elucidating the genetic response and proteins that are mobilized. The protocol uses MS-based determination of the proteins that are expressed in response to an antibiotic, enabling the selection of strong candidates representing putative resistance factors or mechanisms and providing a basis for future studies to understand their implications in antibiotic resistance. This allows us to better understand how the cell responds to the presence of the antibiotic when a specific gene is lost and, consequently, identify alternative targets for possible future treatment development.


Assuntos
Infecções por Escherichia coli , beta-Lactamases , Humanos , beta-Lactamases/genética , beta-Lactamases/metabolismo , Infecções por Escherichia coli/microbiologia , Cromatografia Líquida , Proteômica , Espectrometria de Massas em Tandem , Escherichia coli/genética , Escherichia coli/metabolismo , Antibacterianos/farmacologia , Plasmídeos/genética
5.
Res Microbiol ; 174(1-2): 103987, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36031177

RESUMO

Two Corynebacterium species were proposed decades ago, isolated from clinical samples and divided into biovars: "Corynebacterium genitalium" biovars I-V and "Corynebacterium pseudogenitalium" biovars C1-C6. Several biovars have been re-classified as new species. Nevertheless, biovar I and C5, together with their respective specific epithets "Corynebacterium genitalium" and "Corynebacterium pseudogenitalium", remained not validly published after more than 40 years. Several more strains, temptatively classified as "C. genitalium" biovar I and "Corynebacterium pseudogenitalium" C5, have been isolated from clinical and environmental samples. Both species presented Gram-positive, non-spore forming rod-shaped cells, able to grow aerobically with CO2. Core-genome analysis identified "C. genitalium" to be most closely related to Corynebacterium tuscaniense, Corynebacterium urinipleomorphum, Corynebacterium aquatimens and C appendicis, and Corynebacterium gottingense as the most closely related species to "C. pseudogenitalium". Comprehensive genomic, genotypic, phenotypic analyses, as well as chemotaxonomic, support the proposal for "C. genitalium" and "C. pseudogenitalium" as distinct species within the genus Corynebacterium. The designated type strains of the two species are Furness 392-1T = ATCC 33030T = CCUG 38989T = CCM 9178T = DSM 113155T for C. genitalium sp. nov., nom. rev., and Furness 162-C2T = ATCC 33039T = CCUG 27540T = CCM 9177T = DSM 113154T for C. pseudogenitalium sp. nov., nom. rev.


Assuntos
Corynebacterium , Corynebacterium/genética , Filogenia , DNA Bacteriano/genética , RNA Ribossômico 16S/genética
6.
Artigo em Inglês | MEDLINE | ID: mdl-36360766

RESUMO

We develop a protocol for assessing the impact of an intervention aimed at improving sleep quality among university nursing students. The study is designed as a pilot randomized controlled trial to be applied during the 2022-23 academic year and is registered at Clinical Trials Gov website (NCT05273086). A total of 60 nursing students will be recruited from a Spanish university. They will be divided into two groups: (30) intervention group and (30) control group. The intervention group will attend two cognitive-behavioural therapy sleep programme sessions focused on knowledge of anatomical structures involved in sleep, chronotype, synchronization, and good sleeping habits. Subjective and objective sleep quality will be assessed before and after the intervention for both groups. In addition to sleep quality, socio-demographic parameters, physical activity, lifestyle habits, and anthropometric measures will be considered prior to intervention. Finally, a satisfaction questionnaire will be applied for posterior analysis. This study is an innovative, relevant intervention that aims to improve sleep quality among university nursing students. Both the approach and the use of objective and subjective validated outcome measurements are key features of this study.


Assuntos
Terapia Cognitivo-Comportamental , Estudantes de Enfermagem , Humanos , Qualidade do Sono , Sono , Exercício Físico , Ensaios Clínicos Controlados Aleatórios como Assunto
7.
Artigo em Inglês | MEDLINE | ID: mdl-36231882

RESUMO

Professional football players are exposed to high injury risk due to the physical demands of this sport. The purpose of this study was to characterize the injuries of a professional football team in the First Portuguese League over three consecutive sports seasons. Seventy-one male professional football players in the First Portuguese Football League were followed throughout the sports seasons of 2019/2020, 2020/2021, and 2021/2022. In total, 84 injuries were recorded. Each player missed an average of 16.6 days per injury. Lower limbs were massively affected by injuries across all three seasons, mainly with muscular injuries in the quadriceps and hamstrings and sprains in the tibiotarsal structure. Overall, the injury incidence was considerably higher in matches than in training. The two times of the season that proved most conducive to injuries were the months of July and January. Our results emphasize the importance of monitoring sports performance, including injury occurrence, and assisting in identifying risk factors in professional football. Designing individualized training programs and optimizing prevention and recovery protocols are crucial for maximizing this global process.


Assuntos
Traumatismos em Atletas , Futebol Americano , Futebol , Traumatismos em Atletas/epidemiologia , Futebol Americano/lesões , Humanos , Incidência , Masculino , Portugal/epidemiologia , Estações do Ano , Futebol/lesões
8.
Artigo em Inglês | MEDLINE | ID: mdl-36232117

RESUMO

Neighborhood built environment is associated with domain-specific physical activity. However, few studies with representative samples have examined the association between perceived neighborhood safety indicators and domain-specific active transportation in Latin America. This study aimed to examine the associations of perceived neighborhood safety with domain-specific active transportation in adults from eight Latin American countries. Data were obtained from the Latin American Study of Nutrition and Health (n = 8547, aged 18-65). Active transportation (walking and cycling) was assessed using the long form of the International Physical Activity Questionnaire. Specifically, traffic density and speed as well as street lightening, visibility of residents regarding pedestrians and bicyclists, traffic lights and crosswalks, safety of public spaces during the day and at night, crime rate during the day and at night were used to evaluate perceived neighborhood safety. Slow traffic speeds, unsafe public spaces during the day, and crime during the day were associated with ≥10 min/week vs. <10 min/week of walking. Furthermore, drivers exceeding the speed limit and crime rate during the day were associated with reporting ≥10 min/week vs. <10 min/week of cycling. These results indicate a stronger association of the perceived neighborhood safety with walking compared to cycling.


Assuntos
Planejamento Ambiental , Características da Vizinhança , América Latina , Características de Residência , Segurança , Meios de Transporte , Caminhada
9.
J Am Soc Mass Spectrom ; 33(6): 917-931, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35500907

RESUMO

Fast and accurate identifications of pathogenic bacteria along with their associated antibiotic resistance proteins are of paramount importance for patient treatments and public health. To meet this goal from the mass spectrometry aspect, we have augmented the previously published Microorganism Classification and Identification (MiCId) workflow for this capability. To evaluate the performance of this augmented workflow, we have used MS/MS datafiles from samples of 10 antibiotic resistance bacterial strains belonging to three different species: Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa. The evaluation shows that MiCId's workflow has a sensitivity value around 85% (with a lower bound at about 72%) and a precision greater than 95% in identifying antibiotic resistance proteins. In addition to having high sensitivity and precision, MiCId's workflow is fast and portable, making it a valuable tool for rapid identifications of bacteria as well as detection of their antibiotic resistance proteins. It performs microorganismal identifications, protein identifications, sample biomass estimates, and antibiotic resistance protein identifications in 6-17 min per MS/MS sample using computing resources that are available in most desktop and laptop computers. We have also demonstrated other use of MiCId's workflow. Using MS/MS data sets from samples of two bacterial clonal isolates, one being antibiotic-sensitive while the other being multidrug-resistant, we applied MiCId's workflow to investigate possible mechanisms of antibiotic resistance in these pathogenic bacteria; the results showed that MiCId's conclusions agree with the published study. The new version of MiCId (v.07.01.2021) is freely available for download at https://www.ncbi.nlm.nih.gov/CBBresearch/Yu/downloads.html.


Assuntos
Proteômica , Espectrometria de Massas em Tandem , Antibacterianos/farmacologia , Bactérias/química , Farmacorresistência Bacteriana , Resistência Microbiana a Medicamentos , Escherichia coli , Humanos , Proteômica/métodos , Pseudomonas aeruginosa , Espectrometria de Massas em Tandem/métodos , Fluxo de Trabalho
11.
Front Cell Infect Microbiol ; 11: 634215, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34381737

RESUMO

Bloodstream infections (BSIs), the presence of microorganisms in blood, are potentially serious conditions that can quickly develop into sepsis and life-threatening situations. When assessing proper treatment, rapid diagnosis is the key; besides clinical judgement performed by attending physicians, supporting microbiological tests typically are performed, often requiring microbial isolation and culturing steps, which increases the time required for confirming positive cases of BSI. The additional waiting time forces physicians to prescribe broad-spectrum antibiotics and empirically based treatments, before determining the precise cause of the disease. Thus, alternative and more rapid cultivation-independent methods are needed to improve clinical diagnostics, supporting prompt and accurate treatment and reducing the development of antibiotic resistance. In this study, a culture-independent workflow for pathogen detection and identification in blood samples was developed, using peptide biomarkers and applying bottom-up proteomics analyses, i.e., so-called "proteotyping". To demonstrate the feasibility of detection of blood infectious pathogens, using proteotyping, Escherichia coli and Staphylococcus aureus were included in the study, as the most prominent bacterial causes of bacteremia and sepsis, as well as Candida albicans, one of the most prominent causes of fungemia. Model systems including spiked negative blood samples, as well as positive blood cultures, without further culturing steps, were investigated. Furthermore, an experiment designed to determine the incubation time needed for correct identification of the infectious pathogens in blood cultures was performed. The results for the spiked negative blood samples showed that proteotyping was 100- to 1,000-fold more sensitive, in comparison with the MALDI-TOF MS-based approach. Furthermore, in the analyses of ten positive blood cultures each of E. coli and S. aureus, both the MALDI-TOF MS-based and proteotyping approaches were successful in the identification of E. coli, although only proteotyping could identify S. aureus correctly in all samples. Compared with the MALDI-TOF MS-based approaches, shotgun proteotyping demonstrated higher sensitivity and accuracy, and required significantly shorter incubation time before detection and identification of the correct pathogen could be accomplished.


Assuntos
Bacteriemia , Infecções Estafilocócicas , Bacteriemia/diagnóstico , Candida albicans , Escherichia coli , Humanos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Infecções Estafilocócicas/diagnóstico , Staphylococcus aureus
12.
Microbiol Resour Announc ; 10(19)2021 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-33986075

RESUMO

We report the complete 8.94-Mb genome sequence of the type strain of Cupriavidus basilensis (DSM 11853T = CCUG 49340T = RK1T), formed by two chromosomes and six putative plasmids, which offers insights into its chloroaromatic-biodegrading capabilities.

16.
Int J Syst Evol Microbiol ; 70(12): 6067-6078, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33048039

RESUMO

When analysing a large cohort of Staphylococcus haemolyticus, using whole-genome sequencing, five human isolates (four from the skin and one from a blood culture) with aberrant phenotypic and genotypic traits were identified. They were phenotypically similar with yellow colonies, nearly identical 16S rRNA gene sequences and initially speciated as S. haemolyticus based on 16S rRNA gene sequence and MALDI-TOF MS. However, compared to S. haemolyticus, these five strains demonstrate: (i) considerable phylogenetic distance with an average nucleotide identity <95 % and inferred DNA-DNA hybridization <70  %; (ii) a pigmented phenotype; (iii) urease production; and (iv) different fatty acid composition. Based on the phenotypic and genotypic results, we conclude that these strains represent a novel species, for which the name Staphylococcus borealis sp. nov. is proposed. The novel species belong to the genus Staphylococcus and is coagulase- and oxidase-negative and catalase-positive. The type strain, 51-48T, is deposited in the Culture Collection University of Gothenburg (CCUG 73747T) and in the Spanish Type Culture Collection (CECT 30011T).


Assuntos
Sangue/microbiologia , Filogenia , Pele/microbiologia , Staphylococcus/classificação , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Humanos , Noruega , Hibridização de Ácido Nucleico , Pigmentação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Staphylococcus/isolamento & purificação
17.
Antibiotics (Basel) ; 9(8)2020 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-32722499

RESUMO

Methicillin-resistant Staphylococcus aureus (MRSA) is a prevalent nosocomial pathogen, causing a wide range of diseases. The increased frequency of MRSA isolates in hospitals and the emergence of vancomycin resistance have sparked the search for new control strategies. This study aimed to characterize sixty-seven MRSA isolates collected from both infected patients and asymptomatic carriers in a Spanish hospital. RAPD-PCR allowed the identification of six genetic patterns. We also investigated the presence of genes involved in producing adhesins, toxins and the capsule; the biofilm; and antimicrobial resistance. A notable percentage of the isolates carried virulence genes and showed medium-high ability to form biofilms. Next, we assessed the strains' susceptibility to two phages (phiIPLA-C1C and phiIPLA-RODI) and one endolysin (LysRODI). All strains were resistant to phiIPLA-C1C, and most (70.2%) were susceptible to phiIPLA-RODI. Regarding LysRODI, all strains displayed susceptibility, although to varying degrees. There was a correlation between endolysin susceptibility and the random amplification of polymorphic DNA (RAPD) profile or the presence of some virulence genes (fnbA, eta, etb, PVL and czr), but that was not observed with biofilm-forming ability, strain origin or phage sensitivity. Taken together, these findings can help to explain the factors influencing endolysin effectiveness, which will contribute to the development of efficient therapies targeting MRSA infections.

18.
Int J Syst Evol Microbiol ; 70(8): 4544-4554, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32618559

RESUMO

The taxonomic status of six strains of Acinetobacter obtained from meat samples, collected from supermarkets in Porto, Portugal, was investigated using polyphasic analysis. Partial rpoB sequence similarities lower than 95 % to other Acinetobacter species with validly published names led to the hypothesis that these strains represented novel species. This was confirmed based on comparative multilocus sequence analysis, which included the gyrB, recA and 16S rRNA genes, revealing that these strains represented two coherent lineages that were distinct from each other and from all known species. The names Acinetobacter portensis sp. nov. (comprising four strains) and Acinetobacter guerrae sp. nov. (comprising two strains) are proposed for these novel species. The species status of these two groups was confirmed by low (below 95 %) whole-genome sequence average nucleotide identity values and low (below 70 %) digital DNA-DNA hybridization similarities between the whole-genome sequences of the proposed type strains of each novel species and the representatives of the known Acinetobacter species. Phylogenomic treeing from core genome analysis supported these results. The coherence of each new species lineage was supported by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry differentiation of the species at the protein level, by cellular fatty acid profiles, and by unique and differential combinations of metabolic and physiological properties shared by each novel species. The type strain of A. portensis sp. nov. is AC 877T (=CCUG 68672T=CCM 8789T) and the type strain of A. guerrae sp. nov. is AC 1271T (=CCUG 68674T=CCM 8791T).


Assuntos
Acinetobacter/classificação , Microbiologia de Alimentos , Carne/microbiologia , Filogenia , Acinetobacter/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Genes Bacterianos , Tipagem de Sequências Multilocus , Hibridização de Ácido Nucleico , Portugal , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
19.
J Clin Microbiol ; 57(12)2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31578263

RESUMO

Even though antibiotic resistance in bacteria is a natural phenomenon, the alarming increase in pathogenic bacteria refractory to a wide range of antimicrobials is attracting attention worldwide. Indeed, the World Health Organization (WHO) has recently published a list of priority pathogens for which new antimicrobial alternatives are urgently needed. Among these pathogens, methicillin-resistant Staphylococcus aureus (MRSA) strains are perhaps the best known by the general public. In addition to its potential to acquire antibiotic resistance, S. aureus can produce a large number of virulence factors, such as hemolysins, enterotoxins, and proteases, and exhibits the ability to form biofilms as well as to evolve into different clones that can spread and colonize new environments. This review provides a brief overview of the latest options in antibacterial therapies, mainly focusing on phage therapy. In this regard, the current stage of research about antimicrobial compounds based on bacteriophages and endolysins against MRSA infections is shown and discussed.


Assuntos
Infecção Hospitalar/epidemiologia , Infecção Hospitalar/terapia , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Terapia por Fagos/métodos , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/terapia , Endopeptidases/uso terapêutico , Hospitais , Humanos , Staphylococcus aureus Resistente à Meticilina/virologia
20.
Ann Neurol ; 85(2): 204-217, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30597612

RESUMO

OBJECTIVE: Dysregulation of γ-aminobutyric acidergic (GABAergic) transmission has been reported in lesional acquired epilepsies (gliomas, hippocampal sclerosis). We investigated its involvement in a developmental disorder, human focal cortical dysplasia (FCD), focusing on chloride regulation driving GABAergic signals. METHODS: In vitro recordings of 47 human cortical acute slices from 11 pediatric patients who received operations for FCD were performed on multielectrode arrays. GABAergic receptors and chloride regulators were pharmacologically modulated. Immunostaining for chloride cotransporter KCC2 and interneurons were performed on recorded slices to correlate electrophysiology and expression patterns. RESULTS: FCD slices retain intrinsic epileptogenicity. Thirty-six of 47 slices displayed spontaneous interictal discharges, along with a pattern specific to the histological subtypes. Ictal discharges were induced in proepileptic conditions in 6 of 8 slices in the areas generating spontaneous interictal discharges, with a transition to seizure involving the emergence of preictal discharges. Interictal discharges were sustained by GABAergic signaling, as a GABAA receptor blocker stopped them in 2 of 3 slices. Blockade of NKCC1 Cl- cotransporters further controlled interictal discharges in 9 of 12 cases, revealing a Cl- dysregulation affecting actions of GABA. Immunohistochemistry highlighted decreased expression and changes in KCC2 subcellular localization and a decrease in the number of GAD67-positive interneurons in regions generating interictal discharges. INTERPRETATION: Altered chloride cotransporter expression and changes in interneuron density in FCD may lead to paradoxical depolarization of pyramidal cells. Spontaneous interictal discharges are consequently mediated by GABAergic signals, and targeting chloride regulation in neurons may be considered for the development of new antiepileptic drugs. Ann Neurol 2019; 1-14 ANN NEUROL 2019;85:204-217.


Assuntos
Córtex Cerebral/metabolismo , Epilepsias Parciais/metabolismo , Malformações do Desenvolvimento Cortical/metabolismo , Transmissão Sináptica/fisiologia , Ácido gama-Aminobutírico/metabolismo , Adolescente , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/fisiopatologia , Criança , Pré-Escolar , Eletroencefalografia/métodos , Epilepsias Parciais/diagnóstico por imagem , Epilepsias Parciais/fisiopatologia , Feminino , Humanos , Masculino , Malformações do Desenvolvimento Cortical/diagnóstico por imagem , Malformações do Desenvolvimento Cortical/fisiopatologia
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