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1.
Proc Natl Acad Sci U S A ; 121(3): e2314699121, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38198527

RESUMO

Energy metabolism supports neuronal function. While it is well established that changes in energy metabolism underpin brain plasticity and function, less is known about how individual neurons modulate their metabolic states to meet varying energy demands. This is because most approaches used to examine metabolism in living organisms lack the resolution to visualize energy metabolism within individual circuits, cells, or subcellular regions. Here, we adapted a biosensor for glycolysis, HYlight, for use in Caenorhabditis elegans to image dynamic changes in glycolysis within individual neurons and in vivo. We determined that neurons cell-autonomously perform glycolysis and modulate glycolytic states upon energy stress. By examining glycolysis in specific neurons, we documented a neuronal energy landscape comprising three general observations: 1) glycolytic states in neurons are diverse across individual cell types; 2) for a given condition, glycolytic states within individual neurons are reproducible across animals; and 3) for varying conditions of energy stress, glycolytic states are plastic and adapt to energy demands. Through genetic analyses, we uncovered roles for regulatory enzymes and mitochondrial localization in the cellular and subcellular dynamic regulation of glycolysis. Our study demonstrates the use of a single-cell glycolytic biosensor to examine how energy metabolism is distributed across cells and coupled to dynamic states of neuronal function and uncovers unique relationships between neuronal identities and metabolic landscapes in vivo.


Assuntos
Glicólise , Neurônios , Animais , Metabolismo Energético , Caenorhabditis elegans , Plasticidade Neuronal
2.
bioRxiv ; 2023 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-37662365

RESUMO

Energy metabolism supports neuronal function. While it is well established that changes in energy metabolism underpin brain plasticity and function, less is known about how individual neurons modulate their metabolic states to meet varying energy demands. This is because most approaches used to examine metabolism in living organisms lack the resolution to visualize energy metabolism within individual circuits, cells, or subcellular regions. Here we adapted a biosensor for glycolysis, HYlight, for use in C. elegans to image dynamic changes in glycolysis within individual neurons and in vivo. We determined that neurons perform glycolysis cell-autonomously, and modulate glycolytic states upon energy stress. By examining glycolysis in specific neurons, we documented a neuronal energy landscape comprising three general observations: 1) glycolytic states in neurons are diverse across individual cell types; 2) for a given condition, glycolytic states within individual neurons are reproducible across animals; and 3) for varying conditions of energy stress, glycolytic states are plastic and adapt to energy demands. Through genetic analyses, we uncovered roles for regulatory enzymes and mitochondrial localization in the cellular and subcellular dynamic regulation of glycolysis. Our study demonstrates the use of a single-cell glycolytic biosensor to examine how energy metabolism is distributed across cells and coupled to dynamic states of neuronal function, and uncovers new relationships between neuronal identities and metabolic landscapes in vivo.

3.
Biomed Eng Lett ; 13(3): 375-390, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37519868

RESUMO

Brain-computer interfaces (BCI) translate brain signals into artificial output to restore or replace natural central nervous system (CNS) functions. Multiple processes, including sensorimotor integration, decision-making, motor planning, execution, and updating, are involved in any movement. For example, a BCI may be better able to restore naturalistic motor behaviors if it uses signals from multiple brain areas and decodes natural behaviors' cognitive and motor aspects. This review provides an overview of the preliminary information necessary to plan a BCI project focusing on intracortical implants in primates. Since the brain structure and areas of non-human primates (NHP) are similar to humans, exploring the result of NHP studies will eventually benefit human BCI studies. The different types of BCI systems based on the target cortical area, types of signals, and decoding methods will be discussed. In addition, various successful state-of-the-art cases will be reviewed in more detail, focusing on the general algorithm followed in the real-time system. Finally, an outlook for improving the current BCI research studies will be debated.

4.
Brain Res ; 1814: 148394, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37156320

RESUMO

Patients diagnosed with Parkinson's disease (PD) have difficulty initiating and executing movements due to an acquired imbalance of the basal ganglia thalamocortical circuit secondary to loss of dopaminergic input into the striatum. The unbalanced circuit is hyper-synchronized, presenting as larger and longer bursts of beta-band (13-30 Hz) oscillations in the subthalamic nucleus (STN). As a first step toward a novel PD therapy that aims to improve symptoms through beta desynchronization, we sought to determine if individuals with PD could acquire volitional control of STN beta power in a neurofeedback task. We found a significant difference in STN beta power between task conditions, and relevant brain signal features could be detected and decoded in real time. This demonstration of volitional control of STN beta motivates development of a neurofeedback therapy to modulate PD symptom severity.


Assuntos
Estimulação Encefálica Profunda , Doença de Parkinson , Núcleo Subtalâmico , Humanos , Doença de Parkinson/terapia , Ritmo beta , Gânglios da Base
5.
Cell Rep ; 42(5): 112449, 2023 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-37119136

RESUMO

The lateral prefrontal cortex (LPFC) of primates is thought to play a role in associative learning. However, it remains unclear how LPFC neuronal ensembles dynamically encode and store memories for arbitrary stimulus-response associations. We recorded the activity of neurons in LPFC of two macaques during an associative learning task using multielectrode arrays. During task trials, the color of a symbolic cue indicated the location of one of two possible targets for a saccade. During a trial block, multiple randomly chosen associations were learned by the subjects. A state-space analysis indicated that LPFC neuronal ensembles rapidly learn new stimulus-response associations mirroring the animals' learning. Multiple associations acquired during training are stored in a neuronal subspace and can be retrieved hours after learning. Finally, knowledge of old associations facilitates learning new, similar associations. These results indicate that neuronal ensembles in the primate LPFC provide a flexible and dynamic substrate for associative learning.


Assuntos
Macaca , Neurônios , Animais , Neurônios/fisiologia , Primatas , Aprendizagem , Córtex Pré-Frontal/fisiologia
6.
Proc Natl Acad Sci U S A ; 119(31): e2204407119, 2022 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-35881794

RESUMO

Cellular metabolism is regulated over space and time to ensure that energy production is efficiently matched with consumption. Fluorescent biosensors are useful tools for studying metabolism as they enable real-time detection of metabolite abundance with single-cell resolution. For monitoring glycolysis, the intermediate fructose 1,6-bisphosphate (FBP) is a particularly informative signal as its concentration is strongly correlated with flux through the whole pathway. Using GFP insertion into the ligand-binding domain of the Bacillus subtilis transcriptional regulator CggR, we developed a fluorescent biosensor for FBP termed HYlight. We demonstrate that HYlight can reliably report the real-time dynamics of glycolysis in living cells and tissues, driven by various metabolic or pharmacological perturbations, alone or in combination with other physiologically relevant signals. Using this sensor, we uncovered previously unknown aspects of ß-cell glycolytic heterogeneity and dynamics.


Assuntos
Técnicas Biossensoriais , Frutose , Glicólise , Análise de Célula Única , Fluorescência , Frutose/análise , Frutosedifosfatos/análise , Humanos , Células Secretoras de Insulina/química , Células Secretoras de Insulina/metabolismo , Proteínas Repressoras/química , Proteínas Repressoras/genética , Análise de Célula Única/métodos
7.
ACS Chem Biol ; 16(9): 1709-1720, 2021 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-34431656

RESUMO

Motivated by the growing importance of single fluorescent protein biosensors (SFPBs) in biological research and the difficulty in rationally engineering these tools, we sought to increase the rate at which SFPB designs can be optimized. SFPBs generally consist of three components: a circularly permuted fluorescent protein, a ligand-binding domain, and linkers connecting the two domains. In the absence of predictive methods for biosensor engineering, most designs combining these three components will fail to produce allosteric coupling between ligand binding and fluorescence emission. While methods to construct diverse libraries with variation in the site of GFP insertion and linker sequences have been developed, the remaining bottleneck is the ability to test these libraries for functional biosensors. We address this challenge by applying a massively parallel assay termed "sort-seq," which combines binned fluorescence-activated cell sorting, next-generation sequencing, and maximum likelihood estimation to quantify the brightness and dynamic range for many biosensor variants in parallel. We applied this method to two common biosensor optimization tasks: the choice of insertion site and optimization of linker sequences. The sort-seq assay applied to a maltose-binding protein domain-insertion library not only identified previously described high-dynamic-range variants but also discovered new functional insertion sites with diverse properties. A sort-seq assay performed on a pyruvate biosensor linker library expressed in mammalian cell culture identified linker variants with substantially improved dynamic range. Machine learning models trained on the resulting data can predict dynamic range from linker sequences. This high-throughput approach will accelerate the design and optimization of SFPBs, expanding the biosensor toolbox.


Assuntos
Proteínas de Fluorescência Verde/química , Proteínas Mutantes/química , Imagem Individual de Molécula/métodos , Sequência de Aminoácidos , Escherichia coli/genética , Citometria de Fluxo/métodos , Biblioteca Gênica , Proteínas de Fluorescência Verde/genética , Ensaios de Triagem em Larga Escala , Aprendizado de Máquina , Maltose/química , Proteínas Mutantes/genética , Ligação Proteica , Domínios Proteicos , Ácido Pirúvico/química
8.
Environ Toxicol Chem ; 40(5): 1452-1462, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33512743

RESUMO

An in situ exposure and effects bioassay system was developed for assessing the toxicity of oil spills to aquatic organisms. The assessment tool combines components of 2 previously developed systems, the sediment ecotoxicity assessment ring (SEA Ring) and the drifting particle simulator. The integrated drifting exposure and effects assessment ring (DEEAR) is comprised of a Global Positioning System (GPS) float, a drifter drogue, the SEA Ring, and the Cyclops-7 fluorescent sensor. Polyethylene passive sampling devices (PED) were mounted for an additional means to characterize water quality conditions and exposures. The DEEAR is optimized for evaluating oil exposure and toxicity in the shallow surface mixing layer of marine waters. A short-term preliminary test was conducted in San Diego, California, USA, to verify the operation of the GPS tracking, the iridium communications, and the integrated SEA Ring exposure system. Further, a proof-of-concept demonstration was conducted offshore in the Santa Barbara Channel, where natural oil seeps produce surface slicks and sheens. Two DEEAR units were deployed for 24 h-one within the oil slick and one in an area outside observable slicks. An aerial drone provided tracking of the surface oil and optimal sites for deployment. The DEEAR proof-of-concept demonstrated integrated real-time tracking and characterization of oil exposures by grab samples, PED, and fluorescent sensors. Oil exposures were directly linked to toxic responses in fish and mysids. This novel integrated system shows promise for use in a variety of aquatic sites to more accurately determine in situ oil exposure and toxicity. Environ Toxicol Chem 2021;40:1452-1462. © 2021 SETAC.


Assuntos
Poluição por Petróleo , Petróleo , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , Animais , Organismos Aquáticos , Petróleo/análise , Petróleo/toxicidade , Poluição por Petróleo/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
9.
J Arthroplasty ; 35(6S): S190-S196, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32171492

RESUMO

BACKGROUND: Aseptic loosening remains one of the leading causes for failure of total knee arthroplasty (TKA). We sought to identify early radiographic measures that may associate with aseptic tibial component loosening, emphasizing systematic evaluation of the cement mantle. METHODS: All TKA revisions from 2007 to 2015 with the primary indication of tibial aseptic loosening were identified using in an institutional implant retrieval database. After exclusion criteria, 61 TKAs comprised the study group. A matched control group of 59 TKAs that had not failed at a minimum of 3 years was identified for comparison. Radiographic analysis on all 6-week postoperative radiographs included angulation of components, cement penetration depth, and presence of radiolucency at the implant-cement and bone-cement interfaces. Groups were compared with Student's t-test, chi-squared test, and Mann-Whitney U-test. A final multivariable logistic regression model was formed for the outcome of aseptic loosening. RESULTS: On multivariable analysis, failure was associated with a greater number of zones with cement penetration <2 mm (5.6 vs 3.4 zones, odds ratio [OR] 1.89, P < .001), increasing percent involvement of radiolucency at the implant-cement interface (8.7% vs 3.1%, OR = 1.15, P = .001), and increased varus alignment of the tibial component (1.5° vs 0°, OR = 1.35, P = .014). A greater number of zones with a radiolucent line at the bone-cement interface did not significantly associate (1.1 vs 0.3, P = .091). CONCLUSION: Our results suggest that radiographic indicators of poor cement mantle quality associate with later aseptic loosening. This emphasizes the need for surgeons to perform careful cement technique in order to reduce the risk of TKA failure. LEVEL OF EVIDENCE: III (Case-control).


Assuntos
Artroplastia do Joelho , Prótese do Joelho , Artroplastia do Joelho/efeitos adversos , Cimentos Ósseos , Humanos , Articulação do Joelho/cirurgia , Falha de Prótese , Radiografia , Tíbia/diagnóstico por imagem , Tíbia/cirurgia
10.
J Dent Res ; 99(1): 36-43, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31771385

RESUMO

This multicenter 3-arm, parallel-group, patient-randomized controlled trial compared clinical effectiveness of 3 treatment strategies over 3 y for managing dental caries in primary teeth in UK primary dental care. Participants aged 3 to 7 y with at least 1 primary molar with dentinal carious lesion were randomized across 3 arms (1:1:1 via centrally administered system with variable-length random permuted blocks): C+P, conventional carious lesion management (complete carious tooth tissue removal and restoration placement) with prevention; B+P, biological management (sealing in carious tooth tissue restoratively) with prevention; and PA, prevention alone (diet, plaque removal, fluorides, and fissure sealants). Parents, children, and dentists were not blind to allocated arm. Co-primary outcomes were 1) the proportion of participants with at least 1 episode of dental pain and/or infection and 2) the number of episodes of dental pain and/or infection during follow-up (minimum, 23 mo). In sum, 1,144 participants were randomized (C+P, n = 386; B+P, n = 381; PA, n = 377) by 72 general dental practitioners, of whom 1,058 (C+P, n = 352; B+P, n = 352; PA, n = 354) attended at least 1 study visit and were included in the primary analysis. The median follow-up was 33.8 mo (interquartile range, 23.8 to 36.7). Proportions of participants with at least 1 episode of dental pain and/or infection were as follows: C+P, 42%; B+P, 40%; PA, 45%. There was no evidence of a difference in incidence of dental pain and/or infection when B+P (adjusted risk difference [97.5% CI]: -2% [-10% to 6%]) or PA (4% [-4% to 12%]) was compared with C+P. The mean (SD) number of episodes of dental pain and/or infection were as follows: C+P, 0.62 (0.95); B+P, 0.58 (0.87); and PA, 0.72 (0.98). Superiority could not be concluded for number of episodes between B+P (adjusted incident rate ratio (97.5% CI): 0.95 [0.75 to 1.21]) or PA (1.18 [0.94 to 1.48]) and C+P. In conclusion, there was no evidence of a difference among the 3 treatment approaches for incidence or number of episodes of dental pain and/or infection experienced by these participants with high caries risk and established disease (trial registration: ISRCTN77044005).


Assuntos
Cárie Dentária , Criança , Pré-Escolar , Cárie Dentária/prevenção & controle , Cárie Dentária/terapia , Odontólogos , Humanos , Selantes de Fossas e Fissuras , Papel Profissional , Dente Decíduo
11.
Community Dent Health ; 36(3): 229-236, 2019 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-31437389

RESUMO

OBJECTIVE: To determine the prevalence and severity of dental caries (at dentine and enamel levels of diagnosis) amongst Malaysian children and to investigate determinant factors associated with caries detection at these different thresholds. METHODS: This study involved life-long residents aged 12 years-old in fluoridated and non-fluoridated areas in Malaysia (n=595). The survey was carried out in 16 public schools by a calibrated examiner, using ICDAS-II criteria. A questionnaire on socio-demographic and oral hygiene practices was self-administered by parents/guardians. Data were analysed using Mann-Whitney U tests and logistic regression. RESULTS: The overall response rate was 74.4%. Caries prevalence at the dentine level or at the dentine and enamel level was significantly (p⟨0.001) higher among children in the non-fluoridated area (D1₋6MFT⟩0 = 82.4%, D4₋6MFT⟩0 = 53.5%) than in the fluoridated area (D1₋6MFT⟩0 = 68.7%, D4₋6MFT⟩0 = 25.5%). Considering only the decayed component of the index, no significant differences were observed between the two areas when the detection threshold was set at enamel caries (D1₋3) (p=0.506). However, when the detection criteria were elevated to the level of caries into dentine (D4₋6) there were clear differences between the fluoridated and non-fluoridated areas (p=0.006). Exposure to fluoridated water proved a significant predictor for lower caries prevalence in the statistical model. Children whose father and mother had a low monthly income had a significantly higher dentine caries prevalence. CONCLUSION: Results confirmed existing evidence of the benefit of water fluoridation in caries prevention. Detection criteria set at caries into dentine shows clear differences between fluoridated and non-fluoridated areas. Exposure to fluoridated water and socio-economic status were associated with caries prevalence.


Assuntos
Cárie Dentária , Fluoretação , Criança , Índice CPO , Cárie Dentária/epidemiologia , Cárie Dentária/prevenção & controle , Dentina , Humanos , Malásia/epidemiologia , Prevalência , Abastecimento de Água
12.
Community Dent Health ; 36(1): 33-38, 2019 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-30667189

RESUMO

OBJECTIVE: To assess the acceptability of fluoride varnish and fissure sealant treatments for children. To investigate the acceptability of delivering this treatment in a school setting for children, parents, clinicians and school staff. BASIC RESEARCH DESIGN: Semi-structured interviews (with children, parents, clinicians and school staff) and a questionnaire (for school staff) as part of a two-arm, randomised clinical trial. PARTICIPANTS: Children aged 6-9, their parents, clinical staff and school staff. INTERVENTIONS: Fluoride varnish or fissure sealant was delivered to children from the ages of 6 to 9 years for 36 months, by a community dental service in a school setting. Fluoride varnish was re-applied every 6 months; fissure sealant was applied once to first permanent molars and re-applied as required. RESULTS: Interviews with children a few days after treatment indicated little difference in preference; acceptability at this point was driven by factors such as finding it fun to visit 'the van' (i.e. mobile dental unit) and receiving a "sticker" rather than specific treatment received. Interviews with parents, clinicians and school staff indicated high acceptability of delivering this type of intervention in a school setting; this may have been partly due to the service being delivered by a well-established, child-oriented community dental service which delivered the clinical trial. CONCLUSIONS: Preventive fluoride varnish and fissure sealant treatments in a school setting has high overall acceptability.


Assuntos
Cárie Dentária , Selantes de Fossas e Fissuras , Criança , Cárie Dentária/prevenção & controle , Fluoretos , Fluoretos Tópicos/uso terapêutico , Humanos , Selantes de Fossas e Fissuras/uso terapêutico
13.
Proc Natl Acad Sci U S A ; 115(42): 10654-10659, 2018 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-30257945

RESUMO

Axon degeneration, a hallmark of chemotherapy-induced peripheral neuropathy (CIPN), is thought to be caused by a loss of the essential metabolite nicotinamide adenine dinucleotide (NAD+) via the prodegenerative protein SARM1. Some studies challenge this notion, however, and suggest that an aberrant increase in a direct precursor of NAD+, nicotinamide mononucleotide (NMN), rather than loss of NAD+, is responsible. In support of this idea, blocking NMN accumulation in neurons by expressing a bacterial NMN deamidase protected axons from degeneration. We hypothesized that protection could similarly be achieved by reducing NMN production pharmacologically. To achieve this, we took advantage of an alternative pathway for NAD+ generation that goes through the intermediate nicotinic acid mononucleotide (NAMN), rather than NMN. We discovered that nicotinic acid riboside (NAR), a precursor of NAMN, administered in combination with FK866, an inhibitor of the enzyme nicotinamide phosphoribosyltransferase that produces NMN, protected dorsal root ganglion (DRG) axons against vincristine-induced degeneration as well as NMN deamidase. Introducing a different bacterial enzyme that converts NAMN to NMN reversed this protection. Collectively, our data indicate that maintaining NAD+ is not sufficient to protect DRG neurons from vincristine-induced axon degeneration, and elevating NMN, by itself, is not sufficient to cause degeneration. Nonetheless, the combination of FK866 and NAR, which bypasses NMN formation, may provide a therapeutic strategy for neuroprotection.


Assuntos
Acrilamidas/farmacologia , NAD/metabolismo , Degeneração Neural/prevenção & controle , Neurônios/efeitos dos fármacos , Niacinamida/análogos & derivados , Mononucleotídeo de Nicotinamida/análogos & derivados , Piperidinas/farmacologia , Vincristina/toxicidade , Animais , Antineoplásicos Fitogênicos/toxicidade , Combinação de Medicamentos , Francisella tularensis/enzimologia , Gânglios Espinais/efeitos dos fármacos , Gânglios Espinais/metabolismo , Gânglios Espinais/patologia , Degeneração Neural/induzido quimicamente , Degeneração Neural/metabolismo , Neurônios/metabolismo , Neurônios/patologia , Niacinamida/farmacologia , Mononucleotídeo de Nicotinamida/metabolismo , Nicotinamida Fosforribosiltransferase/antagonistas & inibidores , Nicotinamida Fosforribosiltransferase/metabolismo , Compostos de Piridínio
14.
J Dent Res ; 96(7): 754-761, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28394709

RESUMO

Fissure sealant (FS) and fluoride varnish (FV) are effective in preventing dental caries when compared with a no-treatment control. However, the relative clinical effectiveness of these interventions is uncertain. The objective of the study was to compare the clinical effectiveness of FS and FV in preventing dental caries in first permanent molars (FPMs) in 6- to 7-y-olds. The study design was a randomized clinical trial, with 2 parallel arms. The setting was a targeted-population program that used mobile dental clinics in schools located within areas of high social and economic deprivation in South Wales. A total of 1,016 children were randomized 1:1 to receive either FS or FV. Resin-based FS was applied to caries-free FPMs and maintained at 6-mo intervals. FV was applied at baseline and at 6-mo intervals for 3 y. The main outcome measures were the proportion of children developing caries into dentine (D4-6MFT) on any 1 of up to 4 treated FPMs after 36 mo. At 36 mo, 835 (82%) children remained: 417 in the FS arm and 418 in the FV arm. A smaller proportion of children who received FV ( n = 73, 17.5%) versus FS ( n = 82, 19.6%) developed caries into dentine on at least 1 FPM (odds ratio [OR] = 0.84; 95% CI, 0.59 to 1.21; P = 0.35), a nonstatistically significant difference between FS and FV treatments. The results were similar when the number of newly decayed teeth (OR = 0.86; 95% CI, 0.60 to 1.22) and tooth surfaces (OR = 0.85; 95% CI, 0.59 to 1.21) were examined. In a community oral health program, semiannual application of FV resulted in caries prevention that was not significantly different from that obtained by applying and maintaining FS after 36 mo (EudraCT: 2010-023476-23; ISRCTN: ISRCTN17029222).


Assuntos
Cariostáticos/uso terapêutico , Assistência Odontológica para Crianças/organização & administração , Cárie Dentária/prevenção & controle , Fluoretos Tópicos/uso terapêutico , Selantes de Fossas e Fissuras/uso terapêutico , Criança , Feminino , Promoção da Saúde , Humanos , Masculino , Resultado do Tratamento , País de Gales
15.
Front Neurosci ; 11: 60, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28232788

RESUMO

Motor imagery (MI) activates the sensorimotor system independent of actual movements and might be facilitated by neurofeedback. Knowledge on the interaction between feedback modality and the involved frequency bands during MI-related brain self-regulation is still scarce. Previous studies compared the cortical activity during the MI task with concurrent feedback (MI with feedback condition) to cortical activity during the relaxation task where no feedback was provided (relaxation without feedback condition). The observed differences might, therefore, be related to either the task or the feedback. A proper comparison would necessitate studying a relaxation condition with feedback and a MI task condition without feedback as well. Right-handed healthy subjects performed two tasks, i.e., MI and relaxation, in alternating order. Each of the tasks (MI vs. relaxation) was studied with and without feedback. The respective event-driven oscillatory activity, i.e., sensorimotor desynchronization (during MI) or synchronization (during relaxation), was rewarded with contingent feedback. Importantly, feedback onset was delayed to study the task-related cortical activity in the absence of feedback provision during the delay period. The reward modality was alternated every 15 trials between proprioceptive and visual feedback. Proprioceptive input was superior to visual input to increase the range of task-related spectral perturbations in the α- and ß-band, and was necessary to consistently achieve MI-related sensorimotor desynchronization (ERD) significantly below baseline. These effects occurred in task periods without feedback as well. The increased accuracy and duration of learned brain self-regulation achieved in the proprioceptive condition was specific to the ß-band. MI-related operant learning of brain self-regulation is facilitated by proprioceptive feedback and mediated in the sensorimotor ß-band.

16.
Br Dent J ; 221(6): 315-20, 2016 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-27659635

RESUMO

Background The 2013 Children's Dental Health Survey is the fifth in a series of national surveys.Aims To describe caries prevalence and severity and factors affecting these, in children in England, Wales and Northern Ireland in 2013.Methodology A representative sample of children (aged 5, 8, 12 and 15 years) in England, Wales and Northern Ireland were invited to participate in dental examinations. Caries was measured at both the dentine ('obvious caries') and dentine plus enamel ('clinical caries') levels and analysis included identifying those with indicators of significant burden of caries and identifying predictive factors.Results In 5-year-olds, 40% had obvious caries experience increasing to 56% when enamel lesions were included. In 15-year-olds, the respective figures were 46% and 63%. Fourteen percent of 5-year-olds and 15% of 15-year-olds had a least one indicator of significant levels of caries and those from deprived backgrounds were more likely to fall into this group.Conclusions Overall, the prevalence of caries in children is continuing to decrease, but the rate is slowing. The level of disease for those with disease is much higher than the average values might suggest and there remain a sizeable minority with a significant burden of caries, associated with deprivation. This complex picture poses significant clinical and public health challenges.


Assuntos
Índice CPO , Cárie Dentária/epidemiologia , Adolescente , Criança , Pré-Escolar , Inglaterra/epidemiologia , Feminino , Humanos , Masculino , Irlanda do Norte/epidemiologia , Prevalência , País de Gales/epidemiologia
17.
Br Dent J ; 221(4): 187-94, 2016 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-27561579

RESUMO

Background Much concern appears to exist as to the scope and content of contemporary dental school programmes, with the oft-cited criticism being made that dental graduates are 'no longer as good as they used to be'.Aim The aim of this project was to survey the views of dentists - both new graduates and more established practitioners - on aspects of their own dental school training they felt had been deficient as well as commenting on what aspects of dental school education they would like to see improved/enhanced in current times.Methods An invitation to complete an Internet-based questionnaire was emailed to the Fellows and Members of the Faculty of General Dental Practice (UK). Topics in the questionnaire included the respondent's own dental education history, how well they felt their dental school training had covered certain clinical and non-clinical topics; and their opinions on areas they felt should be included in contemporary dental school programmes.Results Six hundred and forty-nine responses were received from 3,348 emailed invitations (response rate = 19.4%). Sixty-one percent (395) of respondents were qualified for 10 years or more. Among clinical skills and techniques, a majority of respondents reported they felt they had not had sufficient teaching/training in dental school in surgical endodontics (76%), conscious sedation (72%), root surface debridement (71%), fixed orthodontic appliances (68%), porcelain veneers (63%), implants (56%) and posterior composites (53%). If designing a new dental school programme, the most common topics respondents would seek to include/increase were business and practice management (21%), communication skills (including patient management and leadership skills) (10%), and increased clinical time and experience (8%).Conclusions The findings of this project are of interest and relevance to those working with student dentists and young dental practitioners. A greater emphasis is needed on the teaching of certain non-clinical subjects such as business and communication skills, while within clinical subjects there is need to refine and expand teaching in identified areas such as exodontia and endodontics.


Assuntos
Atitude do Pessoal de Saúde , Educação em Odontologia , Faculdades de Odontologia , Odontólogos , Odontologia Geral , Humanos , Inquéritos e Questionários
18.
Community Dent Health ; 33(2): 145-50, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27352470

RESUMO

OBJECTIVE: To assess examiner reliability when scoring dental fluorosis in Malaysian children using clinical (Dean's Index) and photographic methods. METHOD: The upper central incisors of 111 children were examined both clinically and photographically for fluorosis status using Dean's index. Twenty children were re-examined after a two-week interval for intra-examiner reliability by a single examiner. In addition, two independent examiners and the clinical examiner scored 111 photographic images of the same children in a standardized manner. Fluorosis scores were compared individually between examiners for both clinical and photographic scoring. Examiner reliability was assessed using both simple and weighted kappa statistics at tooth level. Sensitivity, specificity, positive-negative predictive values and a Receiver Operating Characteristic (ROC) curve were also calculated to determine the accuracy of the test. RESULTS: Across the three examiners, the prevalence of fluorosis (Dean's score ≥ 2) using photographs was lower (ranged from 23% to 26%) than the prevalence recorded by clinical examination (30%). The kappa score for intra-examiner reliability for the duplicate clinical examination was excellent (0.89). Inter-examiner reliability between the photographic method and the clinical examination (gold standard) for each examiner was substantial with weighted kappa values ranging from 0.74 to 0.77. The photographic method indicated higher specificity (99%) than sensitivity (79%) and the area under the ROC curve was also high (0.89) which suggests good accuracy of the diagnostic test. CONCLUSION: These results suggest that photographic examination of fluorosis on central incisors can be recorded with good examiner reliability. The recorded fluorosis prevalence was lower using the photographic scores.


Assuntos
Fluorose Dentária/classificação , Fotografação/métodos , Área Sob a Curva , Criança , Fluorose Dentária/diagnóstico , Humanos , Processamento de Imagem Assistida por Computador/métodos , Processamento de Imagem Assistida por Computador/estatística & dados numéricos , Incisivo/patologia , Malásia , Variações Dependentes do Observador , Fotografação/estatística & dados numéricos , Valor Preditivo dos Testes , Curva ROC , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
19.
Br Dent J ; 220(9): 451-7, 2016 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-27173703

RESUMO

Aim An exploration of the threshold that dentists, doctors and nurses recognise for dental and child protection (CP) actions in sample clinical cases, and any differences between these professional groups.Method We present a cross-sectional survey of dentists, doctors and nurses (50 each), who regularly examine children, utilised five fictitious vignettes, combining an oral examination image and clinical history reflecting dental and CP issues. Demographics were collected, and each participant gave their likely action for the cases presented.Results Dentists were significantly better at answering the dental element than the doctors and nurses, (P <0.0001) with no significant difference between these two; only 8% of the latter had undergone any training in assessment of dental health. Although 90.6% of all professionals had undergone CP training, dentists were significantly less accurate at identifying the CP component than doctors and nurses, (P <0.0001) between whom there were no significant differences. Those with higher levels of CP training were most accurate at identifying correct CP actions.Conclusions CP training is effective at improving recognition of child maltreatment, although there remains a worrying lack of knowledge about thresholds for action among dentists. Doctors and nurses have minimal training in, or knowledge of, dental health in children, thus precluding appropriate onward referrals.


Assuntos
Maus-Tratos Infantis , Odontólogos , Encaminhamento e Consulta , Atitude do Pessoal de Saúde , Criança , Estudos Transversais , Odontologia Geral , Humanos , Papel Profissional , Inquéritos e Questionários
20.
J Neurophysiol ; 115(1): 486-99, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-26561608

RESUMO

Neurons in the lateral prefrontal cortex (LPFC) encode sensory and cognitive signals, as well as commands for goal-directed actions. Therefore, the LPFC might be a good signal source for a goal-selection brain-computer interface (BCI) that decodes the intended goal of a motor action previous to its execution. As a first step in the development of a goal-selection BCI, we set out to determine if we could decode simple behavioral intentions to direct gaze to eight different locations in space from single-trial LPFC neural activity. We recorded neuronal spiking activity from microelectrode arrays implanted in area 8A of the LPFC of two adult macaques while they made visually guided saccades to one of eight targets in a center-out task. Neuronal activity encoded target location immediately after target presentation, during a delay epoch, during the execution of the saccade, and every combination thereof. Many (40%) of the neurons that encoded target location during multiple epochs preferred different locations during different epochs. Despite heterogeneous and dynamic responses, the neuronal feature set that best predicted target location was the averaged firing rates from the entire trial and it was best classified using linear discriminant analysis (63.6-96.9% in 12 sessions, mean 80.3%; information transfer rate: 21-59, mean 32.8 bits/min). Our results demonstrate that it is possible to decode intended saccade target location from single-trial LPFC activity and suggest that the LPFC is a suitable signal source for a goal-selection cognitive BCI.


Assuntos
Potenciais de Ação , Intenção , Modelos Neurológicos , Neurônios/fisiologia , Córtex Pré-Frontal/fisiologia , Desempenho Psicomotor/fisiologia , Movimentos Sacádicos , Algoritmos , Animais , Teoria da Informação , Macaca fascicularis , Masculino , Estimulação Luminosa , Processamento de Sinais Assistido por Computador
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