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1.
Rev. bras. med. esporte ; 29: e2022_0166, 2023. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1394840

RESUMO

ABSTRACT Introduction: Physical training for the elderly is extremely popular. However, there is a lack of analysis on sports injuries in the elderly. Objective: Study the analysis of movement in sports training techniques and preventing sports injuries in the elderly. Methods: Participating in a 15-minute running and warm-up activity before using the standard FMS test kit, they followed seven test movements, each repeated three times; they did so during six weeks of training based on the recommendations for the prevention of sports injuries presented in this paper. Results: Among the 14 elderly subjects with a total FMS score <14 points, most functional motor scores were 15-16 points, of which 19 points were high, and 9 points were low. In the intervention based on the perspective of sports injuries, the FMS measurement value of the elderly was much better than before, and the evaluation of the technical analysis of movement after the correction was significantly higher than before. Conclusion: The prevention of sports injuries proposed in this paper can effectively help the elderly to prevent sports injuries. This paper considers the FMS trial design as an example for analyzing movements in sports training of the elderly and formulating standards. Level of evidence II; Therapeutic studies - investigation of treatment outcomes.


RESUMO Introdução: O treinamento físico em idosos é extremamente popular, entretanto, carece de análise sobre as lesões esportivas em idosos. Objetivo: Estudar a análise do movimento nas técnicas de treinamento esportivo e a prevenção de lesões esportivas em idosos. Métodos: Participando de uma atividade de 15 minutos de corrida e aquecimento antes de utilizar o kit de teste padrão FMS, seguiram-se sete movimentos de teste, cada um deles repetidos 3 vezes; fizeram-no durante seis semanas de treinamento com base nas recomendações de prevenção de lesões esportivas apresentadas neste trabalho. Resultados: Entre os 14 sujeitos idosos com pontuação total de FMS <14 pontos, a maioria das pontuações motoras funcionais foram de 15-16 pontos, dos quais 19 pontos foram altos e 9 pontos foram baixos. Na intervenção baseada sob a ótica das lesões esportivas, o valor de medição FMS dos idosos foi muito melhor do que anteriormente, e a avaliação da análise técnica do movimento após a correção foi significativamente maior do que aquela antes da correção. Conclusão: A prevenção de lesões esportivas proposta neste trabalho pode efetivamente ajudar os idosos a prevenir as lesões esportivas. Este documento considera o projeto de ensaio do FMS como um exemplo para analisar os movimentos no treinamento esportivo das pessoas idosas e para formular padrões. Nível de evidência II; Estudos terapêuticos - investigação dos resultados do tratamento.


RESUMEN Introducción: El entrenamiento físico en las personas mayores es muy popular, sin embargo, hay una falta de análisis sobre las lesiones deportivas en las personas mayores. Objetivo: Estudiar el análisis del movimiento en las técnicas de entrenamiento deportivo y la prevención de lesiones deportivas en las personas mayores. Métodos: Participando en una actividad de carrera y calentamiento de 15 minutos antes de utilizar el kit de prueba estándar de FMS, se siguieron siete movimientos de prueba, cada uno repetido 3 veces; lo hicieron durante seis semanas de entrenamiento basado en las recomendaciones para la prevención de lesiones deportivas presentadas en este trabajo. Resultados: Entre los 14 sujetos de edad avanzada con una puntuación total de FMS <14 puntos, la mayoría de las puntuaciones motoras funcionales eran de 15-16 puntos, de los cuales 19 puntos eran altos y 9 puntos eran bajos. En la intervención basada en la perspectiva de las lesiones deportivas, el valor de medición de la FMS de los ancianos fue mucho mejor que antes, y la evaluación del análisis técnico del movimiento después de la corrección fue significativamente mayor que antes de la corrección. Conclusión: La prevención de las lesiones deportivas propuesta en este artículo puede ayudar eficazmente a las personas mayores a prevenir las lesiones deportivas. Este documento considera el diseño de la prueba FMS como un ejemplo para analizar los movimientos en el entrenamiento deportivo de las personas mayores y para formular normas. Nivel de evidencia II; Estudios terapéuticos - investigación de los resultados del tratamiento.


Assuntos
Humanos , Masculino , Feminino , Idoso , Traumatismos em Atletas/prevenção & controle , Idoso , Exercício Físico , Teste de Esforço , Desempenho Físico Funcional , Movimento/fisiologia
2.
Exp Neurol ; 359: 114250, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36240882

RESUMO

Orexin is a neuropeptide restrictedly synthesized in the hypothalamus, but extensively modulates the whole brain region activity including prefrontal cortex (PFC), and involved in the pathophysiology of psychiatric disorders. GABAergic interneurons in the mPFC are a promising pharmacological target for developing antidepressant therapies. Here, we examined the effects of the orexin on GABAergic transmission onto pyramidal neurons in the deep layers of the mPFC. We found that bath application of orexin dose-dependently increased the amplitude of evoked IPSCs (eIPSCs). Orexin increased the frequency but not the amplitude of miniature IPSCs (mIPSCs). Ca2+ influx through T-type voltage-gated Ca2+ channels is required for orexin-induced increases in GABA release. We also found orexin increases GABA release probability and the number of releasable vesicles. Orexin depolarizes somatostatin (Sst) interneurons without effects on the firing rate of action potentials (APs) of Sst interneurons. Orexin-induced depolarization of Sst interneurons is independent of extracellular Na+, Ca2+ and T-type Ca2+ channels, but requires inward rectifier K+ channels (Kirs). The present study suggests that orexin enhances GABAergic transmission onto mPFC pyramidal neurons through inhibiting Kirs on Sst interneurons, which further depolarizes interneurons leading to increase in Ca2+ influx via T-type Ca2+ channels. Our results may provide a cellular and molecular mechanism that helps explain the physiological functions of orexin in the brain.


Assuntos
Canais de Potássio Corretores do Fluxo de Internalização , Ratos , Animais , Camundongos , Canais de Potássio Corretores do Fluxo de Internalização/metabolismo , Orexinas/farmacologia , Transmissão Sináptica/fisiologia , Técnicas de Patch-Clamp , Ácido gama-Aminobutírico/farmacologia , Ratos Sprague-Dawley , Células Piramidais/fisiologia , Córtex Pré-Frontal/metabolismo , Interneurônios/fisiologia
3.
Methods Mol Biol ; 2599: 255-270, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36427155

RESUMO

Genetic ablation is a highly efficient method to study regeneration in vivo by stimulating tissue-specific cell death that subsequently induces regrowth and repair in a developing organism. This approach has been particularly successful in Drosophila, for which various temperature-based genetic ablation tools have been developed to explore the complexities of regeneration in larval imaginal discs. Here, we describe the use of a recently established ablation system called DUAL Control, which can be used to both characterize the damage response and genetically manipulate blastema cells to identify novel regulators of regeneration.


Assuntos
Proteínas de Drosophila , Discos Imaginais , Animais , Discos Imaginais/metabolismo , Drosophila/genética , Proteínas de Drosophila/metabolismo , Cicatrização/fisiologia , Larva/metabolismo
4.
Addiction ; 118(1): 30-47, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35851975

RESUMO

BACKGROUND AND AIMS: The ability to regulate emotions effectively has been associated with resilience to psychopathology. Individuals with substance use disorders (SUDs) have been shown to have higher levels of negative emotionality, with some evidence suggesting impairment in emotion regulation compared with individuals without SUDs. However, no previous attempt has been made to systematically review the literature to assess the magnitude of this difference. We aimed to assess the association between SUD diagnosis and emotion regulation as measured by the Difficulties in Emotion Regulation Scale (DERS) and Emotion Regulation Questionnaire (ERQ) through a systematic review and meta-analysis of existing findings. METHODS: The systematic review was conducted using PubMed, PsycINFO and Embase. We examined cross-sectional studies that compared a SUD group with a control group and measured emotion regulation using the DERS or the ERQ. The primary analysis focused on papers using the DERS, as this was the predominant instrument in the literature. RESULTS: Twenty-two studies met our primary analysis criteria, representing 1936 individuals with a SUD and 1567 controls. Individuals with SUDs relative to controls had significantly greater DERS scores, with a mean difference of 21.44 [95% confidence interval (CI) = 16.49-26.40, P < 0.001] and Hedges' g = 1.05 (95% CI = 0.86-1.24, P < 0.001). The difference was robust, remaining significant after removing outliers and studies with high risk of bias. Individuals with SUDs demonstrated poorer emotion regulation on each subscale of the DERS, with the largest deficits in the Strategies and Impulse subscales. The ERQ analysis revealed greater use of expressive suppression in those with SUDs relative to controls (Hedges' g = 0.76, 95% CI = 0.25-1.28, P = 0.004). CONCLUSIONS: People with substance use disorders appear to have greater difficulties in emotion regulation than people without substance use disorders.


Assuntos
Regulação Emocional , Transtornos Relacionados ao Uso de Substâncias , Humanos , Estudos Transversais , Transtornos Relacionados ao Uso de Substâncias/psicologia , Emoções/fisiologia , Inquéritos e Questionários
5.
Methods Mol Biol ; 2598: 45-63, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36355284

RESUMO

Cartilage resides under a low oxygen tension within articulating joints. The oxygen tension within cartilage of the knee joint has been measured to be between 2% and 5% oxygen. Although the literature has historically termed this level of oxygen as hypoxia, particularly when doing experiments in vitro in this range, this is actually the physiological oxygen tension experienced in vivo and is more accurately termed physioxia. In general, culture of chondrogenic cells under physioxia has demonstrated a donor-dependent beneficial effect on chondrogenesis, with an upregulation in cartilage genes (SOX9, COL2A1, ACAN) and matrix deposition (sulfated glycosaminoglycans (sGAGs), collagen II). Physioxia also reduces the expression of hypertrophic markers (COL10A1, MMP13). This chapter will outline the methods for the expansion and differentiation of chondrogenic cells under physioxia using oxygen-controlled incubators and glove box environments, with the typical assays used for qualitative and quantitative assessment of chondrogenesis.


Assuntos
Condrogênese , Células-Tronco Mesenquimais , Condrócitos/metabolismo , Células Cultivadas , Diferenciação Celular/fisiologia , Oxigênio/metabolismo
6.
Methods Mol Biol ; 2598: 289-300, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36355299

RESUMO

Viral gene transfer, known as transduction, is a powerful research tool for studying the biology of chondrocytes in novel ways and also a technology enabling the use of gene therapy for regenerating cartilage and treating diseases that affect cartilage, such as osteoarthritis. Adenovirus, retrovirus, lentivirus, and adeno-associated virus (AAV) are most commonly used to transduce chondrocytes. Although AAV is able to transduce chondrocytes in situ by intra-articular injection, chondrocytes are most commonly transduced in monolayer culture using the four vectors mentioned above. Protocols for achieving this are described, along with a discussion of the variables that can influence transduction efficiency.


Assuntos
Cartilagem Articular , Condrócitos , Condrócitos/fisiologia , Transdução Genética , Vetores Genéticos/genética , Técnicas de Transferência de Genes , Dependovirus/genética , Terapia Genética/métodos , Genes Virais
7.
Arch Gerontol Geriatr ; 104: 104799, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36070636

RESUMO

PURPOSE OF THE RESEARCH: Ageing entails a decrease in muscle mass and strength, known as sarcopenia, which also affects respiratory function. Physical exercise is an appropriate intervention to treat both conditions. This study aims to assess the efficacy of high-intensity resistance training (HIRT) on clinical parameters of respiratory function and health-related quality of life (QoL) in community-dwelling older women with sarcopenia. METHODS: Fifty-one sarcopenic community-dwelling women aged 70 years and older were randomized to either six months of HIRT (n = 24) or control (n = 27). At baseline and post-intervention, participants were assessed for skeletal-muscle sarcopenia; respiratory sarcopenia status; respiratory function: spirometry (FEV1, FVC, FEV1/FVC, and FEF25-75) and expiratory (MEP) and inspiratory (MIP) respiratory muscle strength parameters; and health-related QoL (EURO-QOL 5D-3 L). RESULTS: A group-by-time interaction effect for MEP (p = 0.044, È 2=0.108) was observed. CG showed a significant decrease in FEV1 (mean difference [MD] -0.12 L; 95% confidence interval [CI] -0.20, -0.05; p = 0.002); and FVC (MD -0.18 L; 95% CI -0.33, -0.03; p = 0.024) after six months, whereas the HIRT maintained respiratory function without change. Post-intervention, mean EQ-VAS increased in the HIRT and decreased in CG, resulting in a significant between-group difference (mean 73.0 standard deviation [SD] 16.99 vs 61.1 SD 18.2 points, respectively; p = 0.044). Respiratory sarcopenia status was reverted in the HIRT. CONCLUSIONS: HIRT increased muscle strength and halted age-related respiratory function decline in sarcopenic old women. A strength intervention could benefit health-related QoL and physical well-being. REGISTERED IN CLINICALTRIALS.GOV: NCT03834558.


Assuntos
Treinamento de Força , Sarcopenia , Feminino , Humanos , Idoso , Idoso de 80 Anos ou mais , Sarcopenia/terapia , Treinamento de Força/métodos , Qualidade de Vida , Força Muscular/fisiologia , Músculos Respiratórios
8.
J Mech Behav Biomed Mater ; 137: 105528, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36343521

RESUMO

The exceptional functional performance of articular cartilage (load-bearing and lubrication) is attributed to its poroelastic structure and resulting interstitial fluid pressure. Despite this, there remains no engineered cartilage repair material capable of achieving physiologically relevant poroelasticity. In this work we develop in silico models to guide the design approach for poroelastic mimics of articular cartilage. We implement the constitutive models in FEBio, a PDE solver for multiphasic mechanics problems in biological and soft materials. We investigate the influence of strain rate, boundary conditions at the contact interface, and fiber modulus on the reaction force and load sharing between the solid and fluid phases. The results agree with the existing literature that when fibers are incorporated the fraction of load supported by fluid pressure is greatly amplified and increases with the fiber modulus. This result demonstrates that a stiff fibrous phase is a primary design requirement for poroelastic mimics of articular cartilage. The poroelastic model is fit to experimental stress-relaxation data from bovine and porcine cartilage to determine if sufficient design constraints have been identified. In addition, we fit experimental data from FiHy™, an engineered material which is claimed to be poroelastic. The fiber-reinforced poroelastic model was able to capture the primary physics of these materials and demonstrates that FiHy™ is beginning to approach a cartilage-like poroelastic response. We also develop a fiber-reinforced poroelastic model with a bonded interface (rigid contact) to fit stress relaxation data from an osteochondral explant and FiHy™ + bone substitute. The model fit quality is similar for both the chondral and osteochondral configurations and clearly captures the first order physics. Based on this, we propose that physiological poroelastic mimics of articular cartilage should be developed under a fiber-reinforced poroelastic framework.


Assuntos
Cartilagem Articular , Suínos , Bovinos , Animais , Cartilagem Articular/fisiologia , Elasticidade , Modelos Biológicos , Suporte de Carga , Fenômenos Mecânicos , Estresse Mecânico
9.
Cognition ; 230: 105305, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36228380

RESUMO

Threat has long been supposed to affect human cognitive processing including visual size perception. Whether such threat-related modulation effect varies as a function of spatial frequency is largely unexplored. Here we used low- or high-pass filtered threatening animal and fearful face images as primes and measured their effects on the processing of the Ebbinghaus illusion. Results showed that threatening-animal primes relative to neutral ones significantly decreased the illusion magnitude in low-spatial-frequency rather than in high-spatial-frequency ranges. However, fearful- and neutral-face primes had a comparable effect on the illusion magnitude in both spatial frequency ranges. Notably, when inhibitory transcranial magnetic stimulation was applied to the left temporo-parietal junction (TPJ), fearful-face primes significantly decreased the illusion magnitude in low-spatial-frequency rather than in high-spatial-frequency ranges. However, the opposite pattern of results was observed with right TPJ stimulation. The findings suggest that threat shapes basic aspects of visual perception in a spatial frequency-specific manner, possibly via magnocellular projections from both subcortical and cortical fear-processing systems to early visual cortex.


Assuntos
Ilusões , Humanos , Percepção Visual/fisiologia , Percepção de Tamanho , Medo/fisiologia , Estimulação Magnética Transcraniana , Estimulação Luminosa
10.
Cognition ; 230: 105290, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36240613

RESUMO

Statistical learning relies on detecting the frequency of co-occurrences of items and has been proposed to be crucial for a variety of learning problems, notably to learn and memorize words from fluent speech. Endress and Johnson (2021) (hereafter EJ) recently showed that such results can be explained based on simple memory-less correlational learning mechanisms such as Hebbian Learning. Tovar and Westermann (2022) (hereafter TW) reproduced these results with a different Hebbian model. We show that the main differences between the models are whether temporal decay acts on both the connection weights and the activations (in TW) or only on the activations (in EJ), and whether interference affects weights (in TW) or activations (in EJ). Given that weights and activations are linked through the Hebbian learning rule, the networks behave similarly. However, in contrast to TW, we do not believe that neurophysiological data are relevant to adjudicate between abstract psychological models with little biological detail. Taken together, both models show that different memory-less correlational learning mechanisms provide a parsimonious account of Statistical Learning results. They are consistent with evidence that Statistical Learning might not allow learners to learn and retain words, and Statistical Learning might support predictive processing instead.


Assuntos
Aprendizagem , Fala , Humanos , Aprendizagem/fisiologia
11.
Ultrasonics ; 128: 106860, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36244088

RESUMO

It has been largely documented that local hemodynamic conditions, characterized by low and oscillating wall shear stresses, play a key role in the initiation and progression of vascular atherosclerotic lesions. Thus, investigation of the flow field in the carotid bifurcation can lead to early identification of vulnerable plaques. In this scenario, the development of novel non-invasive imaging tools that can be used in routine clinical practice to identify disturbed and recirculating blood flow becomes crucial. In this context, Vector Flow Imaging is becoming a relevant tool as it provides an angle independent assessment of blood flow velocity and multidimensional flow vector visualization. The purpose of the present study was to validate, in several locations of the carotid bifurcation, the high-frame rate vector flow imaging (HiFR-VFI) technique by comparing with computational fluid dynamic simulations (CFD). In all eight carotid bifurcations, HiFR-VFI accurately detected regions of laminar flow as well as recirculation and unsteady flow areas. An accurate and statistically significant agreement was observed between velocity vectors obtained by HiFR-VFI and those computed by CFD, both for vector magnitude (R = 0.85) and direction (R = 0.74). Our study demonstrated that HiFR-VFI is a valid technique for rapid and advanced visual representation of velocity field in large arteries. Thus, it has a great potential in research-based clinical practice for the identification of flow recirculation, low and oscillating velocity gradients near vessel wall. The use of HiFR-VFI may provide a great improvement in the investigation of the role of local hemodynamics in vascular pathologies, as well in the assessment of the effect of pharmacological treatments.


Assuntos
Artérias Carótidas , Hidrodinâmica , Simulação por Computador , Artérias Carótidas/diagnóstico por imagem , Artérias Carótidas/fisiologia , Velocidade do Fluxo Sanguíneo , Hemodinâmica/fisiologia , Modelos Cardiovasculares
13.
Methods Mol Biol ; 2576: 119-131, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36152181

RESUMO

The transient receptor potential vanilloid 1 ion channel (TRPV1) is a ligand-gated nonselective calcium-permeant cation channel involved in the detection of a wide variety of chemical and physical noxious stimuli, ranging from exogenous and endogenous ligands to noxious heat (>42 °C) and low pH (pH < 5.2). Due to its central role in pain and hyperalgesia, TRPV1 is considered a relevant therapeutic target for the development of analgesic and anti-inflammatory drugs potentially useful to relieve chronic, neuropathic, and inflammatory pain and to treat disorders such as inflammatory bowel disease. In this view, the availability of in vitro assays for the screening of novel TRPV1 modulators is highly desirable. Since TRPV1 activation leads to an increase in the intracellular calcium (Ca2+) levels, the use of Ca2+ fluorescent indicators represent a valuable and sensitive tool for monitoring such intracellular changes. In this chapter, we describe methods for recording and monitoring Ca2+ signals through the fluorescent indicators Fluo-4 acetoxymethyl (AM) and Fura-2 AM in HEK-293 cells transfected with TRPV1 or other thermoTRP channels.


Assuntos
Canais de Potencial de Receptor Transitório , Analgésicos , Cálcio/metabolismo , Capsaicina , Cátions , Fluorescência , Fura-2 , Células HEK293 , Humanos , Ligantes , Dor/tratamento farmacológico , Canais de Cátion TRPV/fisiologia
14.
Methods Mol Biol ; 2576: 461-475, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36152210

RESUMO

Electrophysiological technique is an efficient tool for investigating the synaptic regulatory effects mediated by the endocannabinoid system. Stimulation of presynaptic type 1 cannabinoid receptor (CB1) is the principal mode by which endocannabinoids suppress transmitter release in the central nervous system, but a non-retrograde manner of functioning and other receptors have also been described. Endocannabinoids are key modulators of both short- and long-term plasticity. Here, we discuss ex vivo electrophysiological approaches to examine synaptic signaling induced by cannabinoid and endocannabinoid molecules in the mammalian brain.


Assuntos
Canabinoides , Endocanabinoides , Animais , Moduladores de Receptores de Canabinoides/farmacologia , Moduladores de Receptores de Canabinoides/fisiologia , Mamíferos , Receptores de Canabinoides , Transdução de Sinais/fisiologia , Transmissão Sináptica
15.
J Environ Sci (China) ; 124: 42-49, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36182150

RESUMO

Growing studies have linked metal exposure to diabetes risk. However, these studies had inconsistent results. We used a multiple linear regression model to investigate the sex-specific and dose-response associations between urinary metals (cobalt (Co) and molybdenum (Mo)) and diabetes-related indicators (fasting plasma glucose (FPG), hemoglobin A1c (HbA1c), homeostasis model assessment for insulin resistance (HOMA-IR), and insulin) in a cross-sectional study based on the United States National Health and Nutrition Examination Survey. The urinary metal concentrations of 1423 eligible individuals were stratified on the basis of the quartile distribution. Our results showed that the urinary Co level in males at the fourth quartile (Q4) was strongly correlated with increased FPG (ß = 0.61, 95% CI: 0.17-1.04), HbA1c (ß = 0.31, 95% CI: 0.09-0.54), insulin (ß = 8.18, 95% CI: 2.84-13.52), and HOMA-IR (ß = 3.42, 95% CI: 1.40-5.44) when compared with first quartile (Q1). High urinary Mo levels (Q4 vs. Q1) were associated with elevated FPG (ß = 0.46, 95% CI: 0.17-0.75) and HbA1c (ß = 0.27, 95% CI: 0.11-0.42) in the overall population. Positive linear dose-response associations were observed between urinary Co and insulin (Pnonlinear = 0.513) and HOMA-IR (Pnonlinear = 0.736) in males, as well as a positive linear dose-response relationship between urinary Mo and FPG (Pnonlinear = 0.826) and HbA1c (Pnonlinear = 0.376) in the overall population. Significant sex-specific and dose-response relationships were observed between urinary metals (Co and Mo) and diabetes-related indicators, and the potential mechanisms should be further investigated.


Assuntos
Diabetes Mellitus , Resistência à Insulina , Adulto , Glicemia , Cobalto , Estudos Transversais , Feminino , Hemoglobina A Glicada , Humanos , Insulina , Resistência à Insulina/fisiologia , Masculino , Metais , Molibdênio , Inquéritos Nutricionais , Estados Unidos
16.
J Cell Sci ; 136(5)2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36093836

RESUMO

Intracellular mature viruses (IMVs) are the first and most abundant infectious form of vaccinia virus to assemble during its replication cycle. IMVs can undergo microtubule-based motility, but their directionality and the motor involved in their transport remain unknown. Here, we demonstrate that IMVs, like intracellular enveloped viruses (IEVs), the second form of vaccinia that are wrapped in Golgi-derived membranes, recruit kinesin-1 and undergo anterograde transport. In vitro reconstitution of virion transport in infected cell extracts revealed that IMVs and IEVs move toward microtubule plus ends with respective velocities of 0.66 and 0.56 µm/s. Quantitative imaging established that IMVs and IEVs recruit an average of 139 and 320 kinesin-1 motor complexes, respectively. In the absence of kinesin-1, there was a near-complete loss of in vitro motility and reduction in the intracellular spread of both types of virions. Our observations demonstrate that kinesin-1 transports two morphologically distinct forms of vaccinia. Reconstitution of vaccinia-based microtubule motility in vitro provides a new model to elucidate how motor number and regulation impacts transport of a bona fide kinesin-1 cargo.


Assuntos
Cinesinas , Vaccinia , Extratos Celulares , Humanos , Microtúbulos/metabolismo , Vaccinia/metabolismo , Vírus Vaccinia , Vírion/fisiologia
17.
J Cell Sci ; 136(5)2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36250267

RESUMO

Cells are the smallest building blocks of all living eukaryotic organisms, usually ranging from a couple of micrometers (for example, platelets) to hundreds of micrometers (for example, neurons and oocytes) in size. In eukaryotic cells that are more than 100 µm in diameter, very often a self-organized large-scale movement of cytoplasmic contents, known as cytoplasmic streaming, occurs to compensate for the physical constraints of large cells. In this Review, we discuss cytoplasmic streaming in multiple cell types and the mechanisms driving this event. We particularly focus on the molecular motors responsible for cytoplasmic movements and the biological roles of cytoplasmic streaming in cells. Finally, we describe bulk intercellular flow that transports cytoplasmic materials to the oocyte from its sister germline cells to drive rapid oocyte growth.


Assuntos
Proteínas de Drosophila , Cinesinas , Transporte Biológico/fisiologia , Corrente Citoplasmática/fisiologia , Proteínas de Drosophila/metabolismo , Dineínas/metabolismo , Microtúbulos/metabolismo , Oogênese
18.
Behav Brain Res ; 436: 114060, 2023 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-35987307

RESUMO

Depressive symptoms are associated with altered pupillary responses during learning and reward prediction as well as with changes in neurometabolite levels, including brain concentrations of choline, glutamate and gamma-aminobutyric acid (GABA). However, the full link between depressive symptoms, reward-learning-related pupillary responses and neurometabolites is yet to be established as these constructs have not been assessed in the same individuals. The present pilot study, investigated these relations in a sample of 24 adolescents aged 13 years. Participants completed the Revised Child Anxiety and Depression Scale (RCADS) and underwent a reward learning task while measuring pupil dilation and a single voxel dorsal anterior cingulate cortex (dACC) MEGA-PRESS magnetic resonance spectroscopy scan assessing choline, glutamate and GABA concentrations. Pupil dilation was related to prediction errors (PE) during learning, which was captured by a prediction error-weighted pupil dilation response index (PE-PDR) for each individual. Higher PE-PDR scores, indicating larger pupil dilations to negative prediction errors, were related to lower depressive symptoms and lower dACC choline concentrations. Dorsal ACC choline was positively associated with depressive symptoms, whereas glutamate and GABA were not related to PE-PDR or depressive symptoms. The findings support notions of cholinergic involvement in depressive symptoms and cholinergic influence on reward-related pupillary response, suggesting that pupillary responses to negative prediction errors may hold promise as a biomarker of depressive states.


Assuntos
Depressão , Pupila , Adolescente , Biomarcadores , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Colina , Colinérgicos , Depressão/diagnóstico por imagem , Ácido Glutâmico , Giro do Cíngulo/diagnóstico por imagem , Humanos , Projetos Piloto , Pupila/fisiologia , Ácido gama-Aminobutírico
19.
Behav Brain Res ; 436: 114074, 2023 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-36028001

RESUMO

Functional near-infrared spectroscopy (fNIRS) has been established as an informative modality for understanding the hemodynamic-metabolic correlates of cortical auditory processing. To date, such knowledge has shown broad clinical applications in the diagnosis, treatment, and intervention procedures in disorders affecting auditory processing; however, exploration of the hemodynamic response to auditory tasks is yet incomplete. This holds particularly true in the context of auditory event-related fNIRS experiments, where preliminary work has shown the presence of valid responses while leaving the need for more comprehensive explorations of the hemodynamic correlates of event-related auditory processing. In this study, we apply an individual-specific approach to characterize fNIRS-based hemodynamic changes during an auditory task in healthy adults. Oxygenated hemoglobin (HbO2) concentration change time courses were acquired from eight participants. Independent component analysis (ICA) was then applied to isolate individual-specific class discriminative spatial filters, which were then applied to HbO2 time courses to extract auditory-related hemodynamic features. While six of eight participants produced significant class discriminative features before ICA-based spatial filtering, the proposed method identified significant auditory hemodynamic features in all participants. Furthermore, ICA-based filtering improved correlation between trial labels and extracted features in every participant. For the first time, this study demonstrates hemodynamic features important in experiments exploring auditory processing as well as the utility of individual-specific ICA-based spatial filtering in fNIRS-based feature extraction techniques in auditory experiments. These outcomes provide insights for future studies exploring auditory hemodynamic characteristics and may eventually provide a baseline framework for better understanding auditory response dysfunctions in clinical populations.


Assuntos
Hemodinâmica , Espectroscopia de Luz Próxima ao Infravermelho , Adulto , Hemodinâmica/fisiologia , Hemoglobinas , Humanos , Espectroscopia de Luz Próxima ao Infravermelho/métodos
20.
Behav Brain Res ; 436: 114075, 2023 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-36029892

RESUMO

Regret is a common negative emotion in daily life, and long-term immersion in regret affects mental health. Therefore, to regulate and reduce regret is of wide concern. The current fMRI study aimed to investigate whether outcome anticipation before decision-making could reduce regret and its neural correlates. In the task, participants were asked to anticipate the possible poor outcomes of subsequent decisions, such as missing rewards and meeting punishment, and then made sequential risk-taking decisions. Behavioral results showed that outcome anticipation before decision-making could decrease the intensity of regret, that is, participants felt less regret when they anticipated the outcome before decision-making (anticipation condition, Ant), compared to making sequential risk-taking decisions without any anticipation of the outcome in advance (non-anticipation condition, NAnt). Consistently, at the neural level, stronger activities of ventral striatum (VS) and dorsal medial prefrontal cortex (dmPFC), and greater VS-dmPFC functional connectivity were observed in Ant relative to NAnt. Moreover, the activity of dmPFC was negatively correlated with the intensity of regret in Ant. The current study highlighted that outcome anticipation before decision-making could regulate regret effectively, and dmPFC played a vital role in this process.


Assuntos
Emoções , Estriado Ventral , Tomada de Decisões/fisiologia , Emoções/fisiologia , Humanos , Imageamento por Ressonância Magnética , Córtex Pré-Frontal/diagnóstico por imagem , Recompensa , Estriado Ventral/diagnóstico por imagem
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