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1.
Sci Rep ; 14(1): 17301, 2024 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-39068196

RESUMO

Our ability to skillfully manipulate objects is supported by rapid corrective responses that are initiated when we experience perturbations that interfere with movement goals. For example, the corrective lifting response is triggered when an object is heavier than expected and fails to lift off the surface. In this situation, the absence of expected sensory feedback signalling lift off initiates, within ~ 90 ms, an increase in lifting force. Importantly, when people repeatedly lift an object that, on occasional catch trials, is heavier than expected, the gain of the corrective response, defined as the rate of force increase, adapts to the 'catch' weight. In the present study, we investigated whether this response adaption transfers intermanually. In the training phase, participants used either their left or right hand (counterbalanced) to repeatedly lift a 3 N object that unexpectedly increased to 9 N on catch trials, leading to an increase in the gain of the lifting response across catch trials. Participants then lifted the object with their other hand. On the first catch trial, the gain remained elevated and thus transferred across the hands. This finding suggests that the history of lifts performed by one hand updates the corrective responses for both hands.


Assuntos
Adaptação Fisiológica , Mãos , Remoção , Humanos , Feminino , Masculino , Mãos/fisiologia , Adulto , Adulto Jovem , Desempenho Psicomotor/fisiologia
2.
Brain Behav Immun ; 115: 617-630, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37967662

RESUMO

Birth is an inflammatory event for the newborn, characterized by elevations in interleukin (IL)-6, IL-10, and tumor necrosis factor (TNF)-α peripherally and/or centrally, as well as changes in brain microglia. However, the mechanism(s) underlying these responses is unknown. Toll-like receptors (TLRs) play crucial roles in innate immunity and initiate inflammatory cascades upon recognition of endogenous or exogenous antigens. Most TLR signaling depends on the adaptor molecule myeloid differentiation primary response 88 (MyD88). We independently varied MyD88 gene status in mouse dams and their offspring to determine whether the inflammatory response to birth depends on MyD88 signaling and, if so, whether that signaling occurs in the offspring, the mother, or both. We find that the perinatal surges in plasma IL-6 and brain expression of TNF-α depend solely on MyD88 gene status of the offspring, whereas postnatal increases in plasma IL-10 and TNF-α depend on MyD88 in both the pup and dam. Interestingly, MyD88 genotype of the dam primarily drives differences in offspring brain microglial density and has robust effects on developmental neuronal cell death. Milk cytokines were evaluated as a possible source of postnatal maternal influence; although we found high levels of CXCL1/GROα and several other cytokines in ingested post-partum milk, their presence did not require MyD88. Thus, the inflammatory response previously described in the late-term fetus and newborn depends on MyD88 (and, by extension, TLRs), with signaling in both the dam and offspring contributing. Unexpectedly, naturally-occuring neuronal cell death in the newborn is modulated primarily by maternal MyD88 gene status.


Assuntos
Interleucina-10 , Fator 88 de Diferenciação Mieloide , Animais , Feminino , Camundongos , Gravidez , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Citocinas/metabolismo , Interleucina-10/metabolismo , Interleucina-6/metabolismo , Camundongos Endogâmicos C57BL , Mães , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/metabolismo , Receptores Toll-Like/genética , Receptores Toll-Like/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
3.
J Neurosci ; 43(49): 8525-8535, 2023 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-37884350

RESUMO

Skilled motor performance depends critically on rapid corrective responses that act to preserve the goal of the movement in the face of perturbations. Although it is well established that the gain of corrective responses elicited while reaching toward objects adapts to different contexts, little is known about the adaptability of corrective responses supporting the manipulation of objects after they are grasped. Here, we investigated the adaptability of the corrective response elicited when an object being lifted is heavier than expected and fails to lift off when predicted. This response involves a monotonic increase in vertical load force triggered, within ∼90 ms, by the absence of expected sensory feedback signaling lift off and terminated when actual lift off occurs. Critically, because the actual weight of the object cannot be directly sensed at the moment the object fails to lift off, any adaptation of the corrective response would have to be based on memory from previous lifts. We show that when humans, including men and women, repeatedly lift an object that on occasional catch trials increases from a baseline weight to a fixed heavier weight, they scale the gain of the response (i.e., the rate of force increase) to the heavier weight within two to three catch trials. We also show that the gain of the response scales, on the first catch trial, with the baseline weight of the object. Thus, the gain of the lifting response can be adapted by both short- and long-term experience. Finally, we demonstrate that this adaptation preserves the efficacy of the response across contexts.SIGNIFICANCE STATEMENT Here, we present the first investigation of the adaptability of the corrective lifting response elicited when an object is heavier than expected and fails to lift off when predicted. A striking feature of the response, which is driven by a sensory prediction error arising from the absence of expected sensory feedback, is that the magnitude of the error is unknown. That is, the motor system only receives a categorical error indicating that the object is heavier than expected but not its actual weight. Although the error magnitude is not known at the moment the response is elicited, we show that the response can be scaled to predictions of error magnitude based on both recent and long-term memories.


Assuntos
Força da Mão , Desempenho Psicomotor , Masculino , Humanos , Feminino , Retroalimentação , Desempenho Psicomotor/fisiologia , Força da Mão/fisiologia , Memória de Longo Prazo , Motivação
4.
J Dance Med Sci ; 26(4): 226-231, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36096646

RESUMO

OBJECTIVES: Performance anxiety (PA) is debilitating and impacts the sufferer's ability to perform. Forgetfulness, concentration loss, and physical symptoms develop, leading to some giving up performing.
Methods: An online questionnaire was used to gather data, including demographic questions and the Kenny Music Performance Anxiety Inventory (K-MPAI). The questionnaire was distributed via social media and the British Association for Performing Arts Medicine (BAPAM) database. Data was collected over a 2-month period and was analyzed using simple proportions with a score of ≥ 104 on the K-MPAI indicating the presence of PA and ≥ 130 indicating notable levels of PA.
Results: Thirty-three participants completed the questionnaire (57.6% female). When looking at the ages of participants (18 to 80), the most common age range was 31 to 35 (33%). Two-thirds of participants were deemed to suffer from PA after completing the K-MPAI. A large proportion of participants with PA (63.6%) scored above the threshold score of 130 indicating "significant performance anxiety." Females or currently unemployed performers showed higher levels of PA than other subgroups. However, a chi-squared test showed no significance between sexes (p = 0.32) or employment status (p = 0.31) and the incidence of PA.
Conclusion: The research showed that PA is a significant issue in musical theater, as it is with other musicians who have been studied extensively. We conclude that more research is needed to look at appropriate treatments specifically for musical theater performers.


Assuntos
Dança , Música , Ansiedade de Desempenho , Humanos , Feminino , Masculino , Projetos Piloto , Inquéritos e Questionários
5.
Rheumatology (Oxford) ; 60(1): 277-287, 2021 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-32734288

RESUMO

OBJECTIVE: To determine whether a patient-initiated DMARD self-monitoring service for people on MTX is a cost-effective model of care for patients with RA or PsA. METHODS: An economic evaluation was undertaken alongside a randomized controlled trial involving 100 patients. Outcome measures were quality of life and ESR assessed at baseline and post-intervention. Costs were calculated for healthcare usage using a United Kingdom National Health Service economic perspective. Sensitivity analysis was performed to explore the impact of nurse-led telephone helplines. Uncertainty around the cost-effectiveness ratios was estimated by bootstrapping and analysing the cost-effectiveness planes. RESULTS: Fifty-two patients received the intervention and 48 usual care. The difference in mean cost per case indicated that the intervention was £263 more expensive (P < 0.001; 95% CI: £149.14, £375.86) when the helpline costs were accounted for and £94 cheaper (P = 0.08; 95% CI: -£199.26, £10.41) when these costs were absorbed by the usual service. There were, however, statistically significant savings for the patient (P = 0.02; 95% CI: -£28.98, £3.00). When costs and effectiveness measures of ESR and quality of life measured, using the Short Form-12v1, were combined this did not show the patient-initiated service to be cost-effective at a statistically significant level. CONCLUSION: This patient-initiated service led to reductions in primary and secondary healthcare services that translated into reduced costs, in comparison with usual care, but were not cost-effective. Further work is needed to establish how nurse-led telephone triage services are integrated into rheumatology services and the associated costs of setting up and delivering them. TRIAL REGISTRATION: ClinicalTrials.gov, http://clinicaltrials.gov, ISRCTN21613721.


Assuntos
Antirreumáticos/uso terapêutico , Artrite Psoriásica/tratamento farmacológico , Artrite Reumatoide/tratamento farmacológico , Análise Custo-Benefício , Monitoramento de Medicamentos/economia , Metotrexato/uso terapêutico , Custos de Cuidados de Saúde , Humanos , Programas Nacionais de Saúde/economia , Avaliação de Resultados em Cuidados de Saúde , Padrões de Prática em Enfermagem , Qualidade de Vida , Incerteza , Reino Unido
6.
J Neurophysiol ; 124(3): 994-1004, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32816611

RESUMO

Skillful manipulation requires forming memories of object dynamics, linking applied force to motion. Although it has been assumed that such memories are linked to objects, a recent study showed that people can form separate memories when these are linked to different controlled points on an object (Heald JB, Ingram JN, Flanagan JR, Wolpert DM. Nat Hum Behav 2: 300-311, 2018). In that study, participants controlled the handle of a robotic device to move a virtual bar with circles (control points) on the left and right sides. Participants were instructed to move either the left or right control point to a target on the left or right, respectively, such that the required movement was constant. When these control points were paired with opposing force fields, adaptation was observed. In this previous study, both the controlled point and the target changed between contexts. To assess which of these factors is critical for learning, here, we used a similar paradigm but with a bar that automatically rotated as it was moved. In the first experiment, the bar rotated, such that the left and right control points moved to a common target. In the second experiment, the bar rotated such that a single control point moved to a target located on either the left or right. In both experiments, participants were able to learn opposing force fields applied in the two contexts. We conclude that separate memories of dynamics can be formed for different "contact goals," involving a unique combination of the controlled point on an object and the target location this point "contacts."NEW & NOTEWORTHY Skilled manipulation requires forming memories of object dynamics, previously assumed to be associated with entire objects. However, we recently demonstrated that people can form multiple motor memories when explicitly instructed to move different locations on an object to different targets. Here, we show that separate motor memories can be learned for different contact goals, which involve a unique combination of a control point and target.


Assuntos
Objetivos , Memória/fisiologia , Atividade Motora/fisiologia , Desempenho Psicomotor/fisiologia , Percepção Espacial/fisiologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
7.
J Neurophysiol ; 123(3): 1120-1132, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31995427

RESUMO

Short-term plasticity is a fundamental synaptic property thought to underlie memory and neural processing. The glomerular microcircuit comprises complex excitatory and inhibitory interactions and transmits olfactory nerve signals to the excitatory output neurons, mitral/tufted cells (M/TCs). The major glomerular inhibitory interneurons, short axon cells (SACs) and periglomerular cells (PGCs), both provide feedforward and feedback inhibition to M/TCs and have reciprocal inhibitory synapses between each other. Olfactory input is episodically driven by sniffing. We hypothesized that frequency-dependent short-term plasticity within these inhibitory circuits could influence signals sent to higher-order olfactory networks. To assess short-term plasticity in glomerular circuits and MC outputs, we virally delivered channelrhodopsin-2 (ChR2) in glutamic acid decarboxylase-65 promotor (GAD2-cre) or tyrosine hydroxylase promoter (TH-cre) mice and selectively activated one of these two populations while recording from cells of the other population or from MCs. Selective activation of TH-ChR2-expressing SACs inhibited all recorded GAD2-green fluorescent protein(GFP)-expressing presumptive PGC cells, and activation of GAD2-ChR2 cells inhibited TH-GFP-expressing SACs, indicating reciprocal inhibitory connections. SAC synaptic inhibition of GAD2-expressing cells was significantly facilitated at 5-10 Hz activation frequencies. In contrast, GAD2-ChR2 cell inhibition of TH-expressing cells was activation-frequency independent. Both SAC and PGC inhibition of MCs also exhibited short-term plasticity, pronounced in the 5-20 Hz range corresponding to investigative sniffing frequency ranges. In paired SAC and olfactory nerve electrical stimulations, the SAC to MC synapse was able to markedly suppress MC spiking. These data suggest that short-term plasticity across investigative sniffing ranges may differentially regulate intra- and interglomerular inhibitory circuits to dynamically shape glomerular output signals to downstream targets.NEW & NOTEWORTHY Short-term plasticity is a fundamental synaptic property that modulates synaptic strength based on preceding activity of the synapse. In rodent olfaction, sensory input arrives episodically driven by sniffing rates ranging from quiescent respiration (1-2 Hz) through to investigative sniffing (5-10 Hz). Here we show that glomerular inhibitory networks are exquisitely sensitive to input frequencies and exhibit plasticity proportional to investigative sniffing frequencies. This indicates that olfactory glomerular circuits are dynamically modulated by episodic sniffing input.


Assuntos
Rede Nervosa/fisiologia , Inibição Neural/fisiologia , Plasticidade Neuronal/fisiologia , Neurônios/fisiologia , Bulbo Olfatório/fisiologia , Percepção Olfatória/fisiologia , Animais , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos
8.
eNeuro ; 6(3)2019.
Artigo em Inglês | MEDLINE | ID: mdl-31147391

RESUMO

The major inhibitory interneurons in olfactory bulb (OB) glomeruli are periglomerular cells (PGCs) and short axon cells (SACs). PGCs and SACs provide feedforward inhibition to all classes of projection neurons, but inhibition between PGCs and SACs is not well understood. We crossed Cre and GFP transgenic mice and used virally-delivered optogenetic constructs to selectively activate either SACs or GAD65cre-ChR2-positive PGCs while recording from identified GAD65cre-ChR2-positive PGCs or SACs, respectively, to investigate inhibitory interactions between these two interneuron types. We show that GAD65cre-ChR2-positive PGCs robustly inhibit SACs and SACs strongly inhibit PGCs. SACs form the interglomerular circuit, which inhibits PGCs in distant glomeruli. Activation of GAD65cre-ChR2-positive PGCs monosynaptically inhibit mitral cells (MCs), which complements recent findings that SACs directly inhibit MCs. Thus, both classes of glomerular inhibitory neurons inhibit each other, as well as OB output neurons. We further show that olfactory nerve input to one glomerulus engages the interglomerular circuit and inhibits PGCs in distant glomeruli. Sensory activation of the interglomerular circuit directly inhibits output neurons in other glomeruli and by inhibiting intraglomerular PGCs, may potentially disinhibit output neurons in other glomeruli. The nature and context of odorant stimuli may determine whether inhibition or excitation prevails so that odors are represented in part by patterns of active and inactive glomeruli.


Assuntos
Potenciais Pós-Sinápticos Excitadores , Potenciais Pós-Sinápticos Inibidores , Neurônios/fisiologia , Bulbo Olfatório/fisiologia , Potenciais de Ação , Animais , Feminino , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Inibição Neural , Vias Neurais/fisiologia , Optogenética
9.
Front Cell Neurosci ; 12: 387, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30416429

RESUMO

Output projections of the olfactory bulb (OB) to the olfactory cortex (OCX) and reciprocal feedback projections from OCX provide rapid regulation of OB circuit dynamics and odor processing. Short-term synaptic plasticity (STP), a feature of many synaptic connections in the brain, can modulate the strength of feedback based on preceding network activity. We used light-gated cation channel channelrhodopsin-2 (ChR2) to investigate plasticity of excitatory synaptic currents (EPSCs) evoked at the OCX to granule cell (GC) synapse in the OB. Selective activation of OCX glutamatergic axons/terminals in OB generates strong, frequency-dependent STP in GCs. This plasticity was critically dependent on activation of CaV2.1 channels. As acetylcholine (ACh) modulates CaV2.1 channels in other brain regions and as cholinergic projections from the basal forebrain heavily target the GC layer (GCL) in OB, we investigated whether ACh modulates STP at the OCX→GC synapse. ACh decreases OCX→GC evoked EPSCs, it had no effect on STP. Thus, ACh impact on cortical feedback is independent of CaV2.1-mediated STP. Modulation of OCX feedback to the bulb by modulatory transmitters, such as ACh, or by frequency-dependent STP could regulate the precise balance of excitation and inhibition of GCs. As GCs are a major inhibitory source for OB output neurons, plasticity at the cortical feedback synapse can differentially impact OB output to higher-order networks in situations where ACh inputs are activated or by active sniff sampling of odors.

10.
Arthritis Care Res (Hoboken) ; 70(11): 1607-1613, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29438608

RESUMO

OBJECTIVE: To establish receipt and provision of self-management support for patients with inflammatory arthritis in the UK, and to establish whether receipt of self-management support is associated with patient's knowledge, skills, and confidence to self-manage. METHODS: Questionnaires for patients and health care professionals were sent to members and associates of the National Rheumatoid Arthritis Society. Patients completed the Patient Activation Measure (PAM), and questions about receipt of self-management support. Health care professionals completed the Clinician Support PAM and questions about provision of self-management support. RESULTS: A total of 886 patients and 117 health care professionals completed the survey. Only 15% of patients had attended a structured self-management program. More than half of the patients reported having the skills, confidence, and knowledge to self-manage, and this skill set was associated with receipt of self-management support that was embedded in routine care. All health care professionals felt that patients should be actively involved in their own care, but 60% were unable to offer structured self-management support. Health care professionals reported engaging in more embedded self-management support than patients reported receiving in routine care. CONCLUSION: Only a small proportion of patients with arthritis have attended a structured support program. Although health care professionals report engaging in self-management support embedded in routine care, patients do not necessarily agree, and these differences could impact the experience of patients with arthritis. When embedded self-management support does occur, it is a significant predictor of patients' knowledge, skills, and confidence to self-manage, as opposed to attendance at a structured program.


Assuntos
Artrite/psicologia , Autogestão/psicologia , Adulto , Idoso , Artrite/reabilitação , Atitude do Pessoal de Saúde , Estudos Transversais , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
11.
Musculoskeletal Care ; 16(2): 278-286, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29380961

RESUMO

OBJECTIVES: The aim of the present study was to explore patients' experience of a patient-initiated self-monitoring service for people with rheumatoid or psoriatic arthritis who are on methotrexate. METHODS: The study took the form of qualitative semi-structured interviews, embedded within a randomized controlled trial. Twelve participants who were randomly assigned to the intervention arm were interviewed. Interviews digitally, transcribed verbatim and analysed using inductive thematic analysis. The study received full National Health Service ethics approval from Camden and Islington Community Local Research Ethics Committee (Ref. 09/H0722/91). RESULTS: Analysis revealed five key themes. Participants described usual care as burdensome and an inefficient use of time, particularly those in employment. Being able to self-monitor and initiate their own care increased patients' knowledge about their illness and its treatment, and enabled them to gain a sense of control and ownership over their arthritis. They appreciated the personalized nature of the new service, which allowed them to be seen at a time and by a method more appropriate to their needs. There were, however, some concerns about fidelity to the service protocol, confusion about the lack of consistency between symptoms and laboratory results, and anxiety about self-monitoring. CONCLUSIONS: Overall, participants were positive about the new service, in comparison with usual care, valuing its tailored approach and empowering effects. Further work is needed to ensure adherence to the service protocol and address anxieties around self-monitoring prior to any widespread implementation of the service.


Assuntos
Artrite Psoriásica/psicologia , Artrite Reumatoide/psicologia , Autogestão , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reumatologia/métodos
12.
J Neurosci ; 36(37): 9604-17, 2016 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-27629712

RESUMO

UNLABELLED: Sensory processing shapes our perception. In mammals, odor information is encoded by combinatorial activity patterns of olfactory bulb (OB) glomeruli. Glomeruli are richly interconnected by short axon cells (SACs), which form the interglomerular circuit (IGC). It is unclear how the IGC impacts OB output to downstream neural circuits. We combined in vitro and in vivo electrophysiology with optogenetics in mice and found the following: (1) the IGC potently and monosynaptically inhibits the OB output neurons mitral/tufted cells (MTCs) by GABA release from SACs: (2) gap junction-mediated electrical coupling is strong for the SAC→MTC synapse, but negligible for the SAC→ETC synapse; (3) brief IGC-mediated inhibition is temporally prolonged by the intrinsic properties of MTCs; and (4) sniff frequency IGC activation in vivo generates persistent MTC inhibition. These findings suggest that the temporal sequence of glomerular activation by sensory input determines which stimulus features are transmitted to downstream olfactory networks and those filtered by lateral inhibition. SIGNIFICANCE STATEMENT: Odor identity is encoded by combinatorial patterns of activated glomeruli, the initial signal transformation site of the olfactory system. Lateral circuit processing among activated glomeruli modulates olfactory signal transformation before transmission to higher brain centers. Using a combination of in vitro and in vivo optogenetics, this work demonstrates that interglomerular circuitry produces potent inhibition of olfactory bulb output neurons via direct chemical and electrical synapses as well as by indirect pathways. The direct inhibitory synaptic input engages mitral cell intrinsic membrane properties to generate inhibition that outlasts the initial synaptic action.


Assuntos
Inibição Neural/fisiologia , Neurônios/fisiologia , Bulbo Olfatório/citologia , Condutos Olfatórios/fisiologia , Olfato/fisiologia , Potenciais de Ação/fisiologia , Animais , Channelrhodopsins , Feminino , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Inibição Neural/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Neurotransmissores/farmacologia , Optogenética , Técnicas de Patch-Clamp , Olfato/efeitos dos fármacos , Transmissão Sináptica/fisiologia , Tirosina 3-Mono-Oxigenase/genética , Tirosina 3-Mono-Oxigenase/metabolismo , Proteína Vermelha Fluorescente
13.
J Neurosci ; 36(29): 7779-85, 2016 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-27445153

RESUMO

UNLABELLED: The efficacy of neurotransmission depends on multiple factors, including presynaptic vesicular release of transmitter, postsynaptic receptor populations and clearance/inactivation of the transmitter. In the olfactory bulb (OB), short axon cells (SACs) form an interglomerular circuit that uses GABA and dopamine (DA) as cotransmitters. Selective optical activation of SACs causes GABA and DA co-release, resulting in a fast, postsynaptic GABA inhibitory response and a slower G-protein-coupled DA rebound excitation. In most systems, vesicular release of DA is cleared by the dopamine transporter (DAT). However, in the OB, high levels of specific DA metabolites suggest that enzymatic catalysis by catechol-O-methyl-transferase (COMT) predominates over DAT re-uptake. To assess this possibility we measured the amount of the DA breakdown enzyme, COMT, present in the OB. Compared with the striatum, the brain structure richest in DA terminals, the OB contains 50% more COMT per unit of tissue. Furthermore, the OB has dramatically less DAT compared with striatum, supporting the idea that COMT enzymatic breakdown, rather than DAT recycling, is the predominant mechanism for DA clearance. To functionally assess COMT inactivation of vesicular release of DA we used fast-scan cyclic voltammetry and pharmacological blockade of COMT. In mice expressing ChR2 in tyrosine hydroxylase-containing neurons, optical activation of SACs evoked robust DA release in the glomerular layer. The COMT inhibitor, tolcapone, increased the DA signal ∼2-fold, whereas the DAT inhibitor GBR12909 had no effect. Together, these data indicate that the OB preferentially employs COMT enzymatic inactivation of vesicular release of DA. SIGNIFICANCE STATEMENT: In the olfactory bulb (OB), odors are encoded by glomerular activation patterns. Dopaminergic short axon neurons (SACs) form an extensive network of lateral connections that mediate cross talk among glomeruli, releasing GABA and DA onto sensory nerve terminals and postsynaptic neurons. DA neurons are ∼10-fold more numerous in OB than in ventral tegmental areas that innervate the striatum. We show that OB has abundant expression of the DA catalytic enzyme catechol-O-methyl-transferase (COMT), but negligible expression of the dopamine transporter. Using optogenetics and fast-scan cyclic voltammetry, we show that inhibition of COMT increases DA signals ∼2-fold. Thus, in contrast to the striatum, which has the brain's highest proportion of DAergic synapses, the DA catalytic pathway involving COMT predominates over re-uptake in OB.


Assuntos
Catecol O-Metiltransferase/metabolismo , Dopamina/metabolismo , Bulbo Olfatório/citologia , Bulbo Olfatório/metabolismo , Sinapses/metabolismo , Ácido 3,4-Di-Hidroxifenilacético/metabolismo , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Catecol O-Metiltransferase/genética , Channelrhodopsins , Proteínas da Membrana Plasmática de Transporte de Dopamina/metabolismo , Regulação da Expressão Gênica/genética , Glutamato Descarboxilase/genética , Glutamato Descarboxilase/metabolismo , Ácido Homovanílico/metabolismo , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Tirosina 3-Mono-Oxigenase/metabolismo
14.
J Neurosci ; 36(25): 6820-35, 2016 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-27335411

RESUMO

UNLABELLED: Serotonergic neurons in the brainstem raphe nuclei densely innervate the olfactory bulb (OB), where they can modulate the initial representation and processing of olfactory information. Serotonergic modulation of sensory responses among defined OB cell types is poorly characterized in vivo Here, we used cell-type-specific expression of optical reporters to visualize how raphe stimulation alters sensory responses in two classes of GABAergic neurons of the mouse OB glomerular layer, periglomerular (PG) and short axon (SA) cells, as well as mitral/tufted (MT) cells carrying OB output to piriform cortex. In PG and SA cells, brief (1-4 s) raphe stimulation elicited a large increase in the magnitude of responses linked to inhalation of ambient air, as well as modest increases in the magnitude of odorant-evoked responses. Near-identical effects were observed when the optical reporter of glutamatergic transmission iGluSnFR was expressed in PG and SA cells, suggesting enhanced excitatory input to these neurons. In contrast, in MT cells imaged from the dorsal OB, raphe stimulation elicited a strong increase in resting GCaMP fluorescence with only a slight enhancement of inhalation-linked responses to odorant. Finally, optogenetically stimulating raphe serotonergic afferents in the OB had heterogeneous effects on presumptive MT cells recorded extracellularly, with an overall modest increase in resting and odorant-evoked responses during serotonergic afferent stimulation. These results suggest that serotonergic afferents from raphe dynamically modulate olfactory processing through distinct effects on multiple OB targets, and may alter the degree to which OB output is shaped by inhibition during behavior. SIGNIFICANCE STATEMENT: Modulation of the circuits that process sensory information can profoundly impact how information about the external world is represented and perceived. This study investigates how the serotonergic system modulates the initial processing of olfactory information by the olfactory bulb, an obligatory relay between sensory neurons and cortex. We find that serotonergic projections from the raphe nuclei to the olfactory bulb dramatically enhance the responses of two classes of inhibitory interneurons to sensory input, that this effect is mediated by increased glutamatergic drive onto these neurons, and that serotonergic afferent activation alters the responses of olfactory bulb output neurons in vivo These results elucidate pathways by which neuromodulatory systems can dynamically regulate brain circuits during behavior.


Assuntos
Bulbo Olfatório/citologia , Condutos Olfatórios/fisiologia , Núcleos da Rafe/citologia , Neurônios Serotoninérgicos/fisiologia , Serotonina/metabolismo , Olfato/fisiologia , Potenciais de Ação/efeitos dos fármacos , Potenciais de Ação/genética , Animais , Caderinas/genética , Caderinas/metabolismo , Sinalização do Cálcio/efeitos dos fármacos , Sinalização do Cálcio/fisiologia , Proteínas de Escherichia coli/metabolismo , Proteínas de Escherichia coli/farmacologia , Feminino , Glutamato Descarboxilase/genética , Glutamato Descarboxilase/metabolismo , Proteínas de Fluorescência Verde/metabolismo , Proteínas de Fluorescência Verde/farmacologia , Masculino , Camundongos , Camundongos Transgênicos , Odorantes , Optogenética , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Recombinantes de Fusão/farmacologia , Proteínas da Membrana Plasmática de Transporte de Serotonina/genética , Proteínas da Membrana Plasmática de Transporte de Serotonina/metabolismo , Olfato/genética , Tirosina 3-Mono-Oxigenase/genética , Tirosina 3-Mono-Oxigenase/metabolismo
15.
Ann Rheum Dis ; 75(7): 1343-9, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26290587

RESUMO

OBJECTIVE: To determine the effectiveness of a patient-initiated disease-modifying antirheumatic drugs (DMARD) self-monitoring service for people with rheumatoid (RA) or psoriatic arthritis (PsA) on methotrexate. METHODS: A two-arm, single-centre, randomised controlled trial assessing superiority in relation to healthcare use, clinical and psychosocial outcomes. Participants were 100 adults with either RA or PsA on a stable dose of methotrexate, randomly assigned to usual care or the patient-initiated service. Intervention participants were trained how to understand and interpret their blood tests and use this information to initiate care from their clinical nurse specialist (CNS). The primary outcome was the number of outpatient visits to the CNS during the trial period. Differences between groups were analysed using Poisson regression models. Secondary outcomes were collected at baseline and after the third and sixth blood tests. Disease activity was measured using either the Disease Activity Score in 28 joints or Psoriatic Arthritis Response Criteria (PsARC), pain and fatigue using a visual numeric scale and the Health Assessment Question-II, Hospital Anxiety and Depression Scale and SF12 were completed to assess disability, mood and quality of life, respectively. Differences between groups over time on secondary outcomes were analysed using multilevel models. RESULTS: The patient-initiated DMARD self-monitoring service was associated with 54.55% fewer visits to the CNS (p<0.0001), 6.80% fewer visits to the rheumatologist (p=0.23) and 38.80% fewer visits to the general practitioner (p=0.07), compared with control participants. There was no association between trial arm and any of the clinical or psychosocial outcomes. CONCLUSIONS: The results suggest that a patient-initiated service that incorporates patients' self-monitoring DMARD therapy can lead to significant reductions in healthcare use, while maintaining clinical and psychosocial well-being. TRIAL REGISTRATION NUMBER: ISRCTN21613721.


Assuntos
Antirreumáticos/administração & dosagem , Artrite Psoriásica/tratamento farmacológico , Artrite Reumatoide/tratamento farmacológico , Monitorização Ambulatorial/métodos , Autocuidado/métodos , Assistência Ambulatorial/estatística & dados numéricos , Artrite Psoriásica/sangue , Artrite Reumatoide/sangue , Quimioterapia Combinada , Feminino , Humanos , Masculino , Metotrexato/administração & dosagem , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Resultado do Tratamento
16.
J Neurophysiol ; 115(3): 1208-19, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26655822

RESUMO

Serotoninergic fibers densely innervate olfactory bulb glomeruli, the first sites of synaptic integration in the olfactory system. Acting through 5HT2A receptors, serotonin (5HT) directly excites external tufted cells (ETCs), key excitatory glomerular neurons, and depolarizes some mitral cells (MCs), the olfactory bulb's main output neurons. We further investigated 5HT action on MCs and determined its effects on the two major classes of glomerular interneurons: GABAergic/dopaminergic short axon cells (SACs) and GABAergic periglomerular cells (PGCs). In SACs, 5HT evoked a depolarizing current mediated by 5HT2C receptors but did not significantly impact spike rate. 5HT had no measurable direct effect in PGCs. Serotonin increased spontaneous excitatory and inhibitory postsynaptic currents (sEPSCs and sIPSCs) in PGCs and SACs. Increased sEPSCs were mediated by 5HT2A receptors, suggesting that they are primarily due to enhanced excitatory drive from ETCs. Increased sIPSCs resulted from elevated excitatory drive onto GABAergic interneurons and augmented GABA release from SACs. Serotonin-mediated GABA release from SACs was action potential independent and significantly increased miniature IPSC frequency in glomerular neurons. When focally applied to a glomerulus, 5HT increased MC spontaneous firing greater than twofold but did not increase olfactory nerve-evoked responses. Taken together, 5HT modulates glomerular network activity in several ways: 1) it increases ETC-mediated feed-forward excitation onto MCs, SACs, and PGCs; 2) it increases inhibition of glomerular interneurons; 3) it directly triggers action potential-independent GABA release from SACs; and 4) these network actions increase spontaneous MC firing without enhancing responses to suprathreshold sensory input. This may enhance MC sensitivity while maintaining dynamic range.


Assuntos
Bulbo Olfatório/fisiologia , Serotonina/farmacologia , Sinapses/fisiologia , Potenciais Sinápticos , Animais , Neurônios Dopaminérgicos/efeitos dos fármacos , Neurônios Dopaminérgicos/metabolismo , Neurônios Dopaminérgicos/fisiologia , Neurônios GABAérgicos/efeitos dos fármacos , Neurônios GABAérgicos/metabolismo , Neurônios GABAérgicos/fisiologia , Interneurônios/efeitos dos fármacos , Interneurônios/metabolismo , Interneurônios/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Bulbo Olfatório/citologia , Bulbo Olfatório/metabolismo , Receptor 5-HT2A de Serotonina/metabolismo , Sinapses/efeitos dos fármacos , Sinapses/metabolismo , Ácido gama-Aminobutírico/metabolismo
17.
BMC Health Serv Res ; 15: 565, 2015 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-26684011

RESUMO

BACKGROUND: Self-management interventions have been found to reduce healthcare utilisation in people with long-term conditions, but further work is needed to identify which components of these interventions are most effective. Self-monitoring is one such component and is associated with significant clinical benefits. The aim of this systematic review of reviews is to assess the impact of self-monitoring interventions on healthcare utilisation across a range of chronic illnesses. METHODS: An overview of published systematic reviews and meta-analyses. Multiple databases were searched (MEDLINE, CINAHL, PsycINFO, EMBASE, AMED, EBM and HMIC) along with the reference lists of included reviews. A narrative synthesis was performed, accompanied by calculation of the Corrected Cover Area to understand the impact of overlapping primary research papers. RESULTS: A total of 17 systematic reviews and meta-analyses across three chronic conditions, heart failure, hypertension and chronic obstructive pulmonary disease, were included. Self-monitoring was associated with significant reductions in hospitalisation and re-admissions to hospital. CONCLUSIONS: Self-monitoring has the potential to reduce the pressure placed on secondary care services, but this may lead to increase in services elsewhere in the system. Further work is needed to determine how these findings affect healthcare costs.


Assuntos
Doença Crônica/terapia , Hospitalização/estatística & dados numéricos , Monitorização Fisiológica/métodos , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Autocuidado/estatística & dados numéricos , Doença Crônica/mortalidade , Humanos , Metanálise como Assunto , Monitorização Fisiológica/mortalidade , Literatura de Revisão como Assunto
18.
J Neurosci ; 35(14): 5680-92, 2015 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-25855181

RESUMO

Cholinergic [acetylcholine (ACh)] axons from the basal forebrain innervate olfactory bulb glomeruli, the initial site of synaptic integration in the olfactory system. Both nicotinic acetylcholine receptors (nAChRs) and muscarinic acetylcholine receptors (mAChRs) are expressed in glomeruli. The activation of nAChRs directly excites both mitral/tufted cells (MTCs) and external tufted cells (ETCs), the two major excitatory neurons that transmit glomerular output. The functional roles of mAChRs in glomerular circuits are unknown. We show that the restricted glomerular application of ACh causes rapid, brief nAChR-mediated excitation of both MTCs and ETCs in the mouse olfactory bulb. This excitation is followed by mAChR-mediated inhibition, which is blocked by GABAA receptor antagonists, indicating the engagement of periglomerular cells (PGCs) and/or short axon cells (SACs), the two major glomerular inhibitory neurons. Indeed, selective activation of glomerular mAChRs, with ionotropic GluRs and nAChRs blocked, increased IPSCs in MTCs and ETCs, indicating that mAChRs recruit glomerular inhibitory circuits. Selective activation of glomerular mAChRs in the presence of tetrodotoxin increased IPSCs in all glomerular neurons, indicating action potential-independent enhancement of GABA release from PGC and/or SAC dendrodendritic synapses. mAChR-mediated enhancement of GABA release also presynaptically suppressed the first synapse of the olfactory system via GABAB receptors on sensory terminals. Together, these results indicate that cholinergic modulation of glomerular circuits is biphasic, involving an initial excitation of MTC/ETCs mediated by nAChRs followed by inhibition mediated directly by mAChRs on PGCs/SACs. This may phasically enhance the sensitivity of glomerular outputs to odorants, an action that is consistent with recent in vivo findings.


Assuntos
Rede Nervosa/fisiologia , Inibição Neural/fisiologia , Neurônios/fisiologia , Bulbo Olfatório/citologia , Receptores Muscarínicos/metabolismo , Sinapses/fisiologia , Acetilcolina/farmacologia , Potenciais de Ação/fisiologia , Animais , Channelrhodopsins , Colina O-Acetiltransferase/genética , Colinérgicos/farmacologia , Técnicas In Vitro , Potenciais Pós-Sinápticos Inibidores/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Rede Nervosa/efeitos dos fármacos , Inibição Neural/efeitos dos fármacos , Neurotransmissores/farmacologia , Bloqueadores dos Canais de Sódio/farmacologia , Sinapses/efeitos dos fármacos , Tetrodotoxina/farmacologia , Tirosina 3-Mono-Oxigenase/genética , Tirosina 3-Mono-Oxigenase/metabolismo
19.
J Neurophysiol ; 113(9): 3112-29, 2015 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-25717156

RESUMO

Olfaction in mammals is a dynamic process driven by the inhalation of air through the nasal cavity. Inhalation determines the temporal structure of sensory neuron responses and shapes the neural dynamics underlying central olfactory processing. Inhalation-linked bursts of activity among olfactory bulb (OB) output neurons [mitral/tufted cells (MCs)] are temporally transformed relative to those of sensory neurons. We investigated how OB circuits shape inhalation-driven dynamics in MCs using a modeling approach that was highly constrained by experimental results. First, we constructed models of canonical OB circuits that included mono- and disynaptic feedforward excitation, recurrent inhibition and feedforward inhibition of the MC. We then used experimental data to drive inputs to the models and to tune parameters; inputs were derived from sensory neuron responses during natural odorant sampling (sniffing) in awake rats, and model output was compared with recordings of MC responses to odorants sampled with the same sniff waveforms. This approach allowed us to identify OB circuit features underlying the temporal transformation of sensory inputs into inhalation-linked patterns of MC spike output. We found that realistic input-output transformations can be achieved independently by multiple circuits, including feedforward inhibition with slow onset and decay kinetics and parallel feedforward MC excitation mediated by external tufted cells. We also found that recurrent and feedforward inhibition had differential impacts on MC firing rates and on inhalation-linked response dynamics. These results highlight the importance of investigating neural circuits in a naturalistic context and provide a framework for further explorations of signal processing by OB networks.


Assuntos
Rede Nervosa/fisiologia , Neurônios Aferentes/fisiologia , Bulbo Olfatório/citologia , Condutos Olfatórios/fisiologia , Olfato/fisiologia , Potenciais de Ação/fisiologia , Algoritmos , Animais , Simulação por Computador , Humanos , Modelos Neurológicos , Odorantes , Ratos , Vigília
20.
Musculoskeletal Care ; 13(2): 84-92, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25470575

RESUMO

OBJECTIVES: The aim of the present study was to examine the difference between osteoarthritis patients' self-reported assessments of current pain, stiffness and physical function and their expectations of these symptoms in one and five years' time, and to determine the significant predictors of positive expectations. METHODS: Eighty patients completed ratings of baseline assessments and one- and five-year expectations of pain, stiffness and physical function using the Western Ontario and McMaster Osteoarthritis Index (WOMAC). Measures of illness perceptions, coping styles, health values, satisfaction, quality of life, optimism, self-esteem and moods were also collected at baseline. Agreement between patients' current assessment and expectations were calculated using intra-class correlations (ICCs). Paired-sample t-tests were conducted to look at differences between assessments. Univariate logistic regressions were then performed to identify the variables significantly associated with positive expectations of pain, stiffness and function. Significant variables (p < 0.05) were entered into a forward stepwise multivariate logistic regression to identify unique independent predictors of positive expectations for each of the WOMAC subscales. RESULTS: Differences were found between current assessments and expectations, with the majority of patients being positive about future symptoms. There were some differences between the predictors for one- and five-year expectations, with current assessments of health status only affecting five-year expectations. CONCLUSIONS: It is necessary to investigate further the variables that may contribute to positive expectations in osteoarthritis patients in order to manage the condition more effectively.


Assuntos
Osteoartrite do Quadril/fisiopatologia , Osteoartrite do Quadril/psicologia , Osteoartrite do Joelho/fisiopatologia , Osteoartrite do Joelho/psicologia , Dor/etiologia , Adulto , Afeto , Idoso , Idoso de 80 Anos ou mais , Feminino , Nível de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Osteoartrite do Quadril/complicações , Osteoartrite do Joelho/complicações , Dor/fisiopatologia , Dor/psicologia , Qualidade de Vida , Amplitude de Movimento Articular , Autoimagem , Fatores de Tempo
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