Examining the relationship between life skill development and negative experiences in sport: The influence of resilience

A study by Kendellen and Camire (2015) demonstrated that sport participants not only experienced positive outcomes (i.e., development of life skills), but also encounter numerous examples of negative experiences (i.e., anxiety, aggression, negative interactions with coaches, and prioritizing sport over school). Negative experiences have been linked to an increased risk of detrimental outcomes, such as mental and behavioral health concerns. However, there is a paucity of research examining the impact that negative experiences have on positive outcomes. Utilizing a risk and resiliency framework (Fraser et al., 1999), which proposes that individuals have the capability of attaining positive outcomes even when encountering risk factors, the current study examines the relationship between college club sport participants’ negative experiences and life skill development, and whether the demonstration of resilience can mitigate the impact of sport risks. A total of 87 university students who participated in college club sports completed an online survey. Results from a series of linear regression analyses indicated that lacking coach support hindered the development of life skills, while the athletic identity positively predicted life skill development. However, findings did not support the inclusion of resilience in moderating the relationship between negative experiences and life skills. Ultimately, the current study supports a continued focus on facilitating positive coach support and developing a more balanced identity for college club sport participants, which would furthermore ensure the positive development of all youth

Avaliação dos sinais radiográficos preditivos da relação do canal mandibular com as raízes dos terceiros molares inferiores observados em radiografias panorâmicas: revisão de literatura

TCC (graduação) - Universidade Federal de Santa Catarina. Centro de Ciências da Saúde. Odontologia.A Radiografia Panorâmica (RP) é o exame mais utilizado para avaliação da relação do Canal Mandibular (CM) com as raízes do Terceiro Molar Inferior (TMI). Nesse exame é possível observar sinais radiográficos que sugerem a relação das raízes com o CM e que dessa forma, podem prever o risco de comprometimento do nervo alveolar inferior. Um método mais sensível que as RPs para esse fim é a Tomografia Computadorizada de Feixe Cônico (TCFC). Suas imagens permitem uma análise tridimensional da relação das raízes dos TMI com o CM (ROOD, SHEHAB, 1990). O presente estudo tem como objetivos avaliar a sensibilidade e especificidade dos sinais radiográficos em RPs e avaliar os tipos de sinais radiográficos, assim como as suas prevalências. A revisão da literatura foi realizada a partir das bases de dados Pubmed, Medline e Google Acadêmico, com palavras-chave livres e MeSH Terms escolhidas de acordo com o problema selecionado para o trabalho. O maior valor de sensibilidade encontrado foi do sinal interrupção da radiopacidade do CM (80%) e o maior valor de especificidade foi do sinal desvio do CM (98%). O sinal desvio do CM obteve maior valor preditivo positivo (27,9%) e os maiores valores preditivos negativos foram encontrados nos sinais de interrupção da radiopacidade do CM, desvio do CM e escurecimento da raiz (98%). As posições interradicular e lingual do CM em relação ao terceiro molar foram relacionadas com lesão ao NAI. A ausência dos sinais não demonstrou absoluta confiabilidade. Dessa forma, conclui-se que os sinais radiográficos não se mostraram totalmente sensíveis em RPs, sua ausência não reproduz confiabilidade e os sinais que apresentaram mais relatos de relação entre as estruturas foram interrupção da radiopacidade do CM e escurecimento da raiz.The Panoramic Radiograph (PR) is the imaging method of choice to evaluate the relationship between the Mandibular Canal (MC) and the roots of the Mandibular Third Molar (MTM). In this imaging method, radiographic signs can be observed, and these suggest which relations can be found between the roots and the MC and, thus predict the risk of inferior alveolar nerve impairment. A more sensitive method than PR for this purpose is Cone Bean Computed Tomography (CBCT). CBCT imaging allows a three-dimensional analysis of the relationship between the roots of the MTM with the MC (ROOD, SHEHAB, 1990). The present study aims to evaluate the sensitivity and specificity of the radiographic signs in PR and to evaluate the types of radiographic signs, as well as their prevalence. The review of the literature was performed by using Pubmed, Medline and Google Scholar databases, with free keywords and MeSH Terms chosen according to the problem selected for the study. The highest sensitivity value found was for the sign interruption of the MC radiopacity (80%) and the highest specificity was for the sign deviation of the MC (98%). The radiographic sign deviation of the MC obtained a higher positive predictive value (27.9%) and the highest negative predictive value was found in the signs of interruption of MC radiopacity, deviation of the MC, and darkening of the root (98%). The interradicular and lingual positions of the MC relative to the MTM were associated to the nerve injury. The absence of radiographic signs did not demonstrate an absolute reliability. Thus, we conclude that radiographic signs were not fully sensitive in PR, the absence of the signs does not reproduce reliability and the signs that presented more reports of relation between the structures were interruption of the MC radiopacity and darkening of the root

Participação de a-adrenoceptores do núcleo mediano da rafe no controle da resposta ingestiva em ratos saciados

Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Biológicas, Programa de Pós-Graduação em Neurociências, Florianópolis, 2014.O presente estudo avaliou a participação de a-adrenoceptores do núcleo mediano da rafe (NMR) de ratos saciados, nas variáveis de ingestão de alimentos e água e comportamentos não ingestivos. Os animais controle foram tratados com salina (SAL) ou adrenalina (ADR), injetados no NMR sete minutos após a injeção do veículo utilizado para solubilizar os antagonistas, propilenoglicol (PLG) ou SAL. Os animais dos grupos experimentais foram tratados com um antagonista de a-adrenoceptores, prazosina (a1, 20 ou 40nmol) ou ioimbina (a2, 20 ou 40nmol) ou fentolamina (a não seletivo, 20 ou 40nmol), seguido, sete minutos após, pela injeção de ADR ou SAL. Os comportamentos foram registrados durante 30 minutos. Os resultados indicam que a injeção de ADR, assim como o bloqueio de receptores a1 resulta em hiperfagia, por outro lado, o bloqueio de a2 ou de a1 e a2 simultaneamente não altera o comportamento ingestivo. O pré-tratamento do núcleo mediano da rafe com a prazosina, seguida da injeção de ADR, não foi capaz de causar um incremento na quantidade de alimento ingerido após cada um separadamente, embora a maior dose (40nmol) tenha reduzido a latência para iniciar o comportamento ingestivo. O pré-tratamento com a ioimbina ou com a fentolamina, seguido de ADR, bloqueou o comportamento ingestivo induzido pela ADR sozinha. O presente estudo reforça a ideia de que existe uma ativação tônica de a1-adrenoceptores no NMR, que ativa uma influência inibitória (provavelmente neurônios serotonérgicos) em áreas que controlam a ingestão de alimentos. A ADR, ao ativar receptores a2, leva a uma queda na disponibilidade de catecolamina endógena na sinapse, o que reduz a liberação de 5-HT e leva à hiperfagia.Abstract : The present study evaluated the involvement of a-adrenoceptors of the median raphe nucleus (MRN) in satiated rats, in the variables of food and water intake and non ingestive behaviours. Control animals were treated with saline (SAL) or adrenaline (ADR), injected into the MRN seven minutes after the injection of the vehicle used to solubilize the antagonists, propylene glycol (PLG) or SAL. The animals of the experimental groups were treated with an a-adrenoceptor antagonist, prazosin (a1, 20 or 40nmol) or yohimbine (a2, 20 or 40nmol) or phentolamine (non-selective a, 20 or 40nmol), followed (seven minutes after) by the injection of ADR or SAL. The behaviours were recorded for 30 minutes. The results indicate that the injection of ADR and the blockade of a1 receptors result in hyperphagia, on the other hand, blocking a2 or a1 and a2 simultaneously does not change feeding behaviour. Pretreatment of the MRN with prazosin, followed by the injection of ADR was not able to cause an increase in the amount of food ingested by each one, while the highest dose (40nmol) reduced the latency to start feeding. Pretreatment with phentolamine or yohimbine, followed by ADR blocks feeding induced by ADR itself. The present study reinforces the idea that there is a tonic activation of a1-adrenoceptors in the MRN, which activates an inhibitory influence (probably serotonergic neurons) in areas that control food intake. ADR activates a2 receptors, resulting in a decrease in the availability of endogenous catecholamines at the synapse, which reduces the release of 5-HT and leads to hyperphagia

Differential roles of specific sub-regions of the longitudinal axis of the hippocampus in the behavioural and neurogenesis responses to stress and antidepressant drugs

Accumulating evidence suggests that the hippocampus is functionally segregated along its longitudinal axis into a dorsal (dHi) and a ventral sub-region (vHi). Indeed, recent gene expression studies suggest that the hippocampus has a gradient of gene expression and that the area between the dHi and vHi, the intermediate hippocampus (iHi), may also be functionally independent, but it remains understudied. The hippocampus is also one of few brain regions where neurogenesis, the birth of new neurons, occurs throughout life and this process has been shown to play roles in learning and memory as well as in responses to stress and antidepressants. These diverse roles may be related to the functional segregation of the hippocampus along its longitudinal axis. Indeed, the dorsal hippocampus (dHi) plays a predominant role in spatial learning and memory, while the ventral hippocampus (vHi) is predominantly involved in the regulation of anxiety, a behaviour impacted by stress and chronic treatment with some antidepressants. In vivo studies have shown that chronic stress and chronic antidepressant treatment change neurogenesis preferentially in the vHi rather than the dHi. However, whether these findings are due to differential intrinsic sensitivities of neural progenitor cells (NPCs) resident in the dHi, iHi or vHi in response to the stress hormone corticosterone or in response to antidepressants is unknown. Moreover, the roles of the dHi, iHi and vHi in the behavioural responses to chronic stress, a risk factor for depression and anxiety disorders, and in the behavioural responses to acute and chronic antidepressant treatment have not yet been investigated. Thus, the aims of this thesis were to determine whether NPCs isolated from the dHi, iHi and vHi have differential intrinsic sensitivities in response to the stress hormone corticosterone, the glucocorticoid receptor agonist dexamethasone, and the antidepressant, fluoxetine. To this end, we isolated NPCs from the three hippocampal sub-regions and cultured them for 4 h or 4 days in vitro with either corticosterone, fluoxetine, or corticosterone with fluoxetine or for 7 days in vitro with either corticosterone or dexamethasone. Cell proliferation, neuronal differentiation and maturation, nuclear GR expression and cell viability were then assessed. Moreover, we also aimed to determine the roles of each hippocampal sub-region on emotional behaviours and neuroendocrine response under baseline conditions, chronic psychosocial stress conditions and under chronic antidepressant treatment conditions. To this end, we performed stereotaxic surgeries in C57BL/6 mice to lesion the dHi, iHi or vHi with ibotenic acid. After recovery, animals were submitted to emotional behaviour and neuroendocrine tests under baseline conditions, or after chronic psychosocial stress, or after acute and chronic fluoxetine treatment. As result, we determined for the first time that NPCs isolated from the iHi and especially vHi are more sensitive to the effects of long-term exposure (7 DIV) to corticosterone and dexamethasone. Long-term (7 DIV) corticosterone and dexamethasone exposure also reduced nuclear GR expression preferentially in cells from the vHi. Fluoxetine alone did not have any effect on cell proliferation or neuronal differentiation or maturation. However, fluoxetine prevented corticosterone-induced reductions in neuronal differentiation after 4 DIV treatment and these effects were observed predominantly in the iHi and vHi cell cultures. In vivo experiments showed that vHi lesions reduced anxiety under baseline conditions. Under chronic psychosocial stress conditions, iHi lesions increased stress-induced social avoidance and the lesion of all sub-regions prevented chronic stress-induced anxiety; dHi and vHi lesions prevented stress-induced anhedonia and only vHi lesions caused antidepressant-like behaviour in the forced swim test and promoted active coping behaviour. In the antidepressant experiment, vHi lesions prevented the antidepressant effects of acute fluoxetine treatment while iHi lesions prevented the antidepressant effects of chronic fluoxetine treatment, and both iHi and vHi lesions prevented the anxiolytic effects of chronic fluoxetine treatment. Taken together, these findings show for the first time that iHi and vHi NPCs have increased intrinsic sensitivity to longer term exposure to the stress hormone corticosterone, and that the vHi seems to be an important sub-region for antidepressant-like effects under chronic stress. Also, both the iHi and vHi but not the dHi seem to modulate the antidepressant and anxiolytic effects of fluoxetine

Inhibition of FKBP51 induces stress resilience and alters hippocampal neurogenesis

Stress-related psychiatric disorders such as depression are among the leading causes of morbidity and mortality. Considering that many individuals fail to respond to currently available antidepressant drugs, there is a need for antidepressants with novel mechanisms. Polymorphisms in the gene encoding FK506-binding protein 51 (FKBP51), a co-chaperone of the glucocorticoid receptor, have been linked to susceptibility to stress-related psychiatric disorders. Whether this protein can be targeted for their treatment remains largely unexplored. The aim of this work was to investigate whether inhibition of FKBP51 with SAFit2, a novel selective inhibitor, promotes hippocampal neuron outgrowth and neurogenesis in vitro and stress resilience in vivo in a mouse model of chronic psychosocial stress. Primary hippocampal neuronal cultures or hippocampal neural progenitor cells (NPCs) were treated with SAFit2 and neuronal differentiation and cell proliferation were analyzed. Male C57BL/6 mice were administered SAFit2 while concurrently undergoing a chronic stress paradigm comprising of intermittent social defeat and overcrowding, and anxiety and depressive -related behaviors were evaluated. SAFit2 increased neurite outgrowth and number of branch points to a greater extent than brain derived neurotrophic factor (BDNF) in primary hippocampal neuronal cultures. SAFit2 increased hippocampal NPC neurogenesis and increased neurite complexity and length of these differentiated neurons. In vivo, chronic SAFit2 administration prevented stress-induced social avoidance, decreased anxiety in the novelty-induced hypophagia test, and prevented stress-induced anxiety in the open field but did not alter adult hippocampal neurogenesis in stressed animals. These data warrant further exploration of inhibition of FKBP51 as a strategy to treat stress-related disorders.Fil: Codagnone, Martín Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Biología Celular y Neurociencia "Prof. Eduardo de Robertis". Universidad de Buenos Aires. Facultad de Medicina. Instituto de Biología Celular y Neurociencia; ArgentinaFil: Kara, Nirit. University College Cork; IrlandaFil: Ratsika, Anna. University College Cork; IrlandaFil: Rocha Levone, Brunno. University College Cork; IrlandaFil: van de Wouw, Marcel. University College Cork; IrlandaFil: Tan, Laura A.. No especifíca;Fil: Cunningham, Jacobi I.. No especifíca;Fil: Sanchez, Connie. No especifíca;Fil: Cryan, John F.. University College Cork; IrlandaFil: O'Leary, Olivia F.. University College Cork; Irland

The phase separation-dependent FUS interactome reveals nuclear and cytoplasmic function of liquid–liquid phase separation

Liquid–liquid phase separation (LLPS) of proteins and RNAs has emerged as the driving force underlying the formation of membrane-less organelles. Such biomolecular condensates have various biological functions and have been linked to disease. The protein Fused in Sarcoma (FUS) undergoes LLPS and mutations in FUS have been causally linked to the motor neuron disease Amyotrophic Lateral Sclerosis (ALS-FUS). LLPS followed by aggregation of cytoplasmic FUS has been proposed to be a crucial disease mechanism. However, it is currently unclear how LLPS impacts the behaviour of FUS in cells, e.g. its interactome. Hence, we developed a method allowing for the purification of LLPS FUS-containing droplets from cell lysates. We observe substantial alterations in the interactome, depending on its biophysical state. While non-LLPS FUS interacts mainly with factors involved in pre-mRNA processing, LLPS FUS predominantly binds to proteins involved in chromatin remodelling and DNA damage repair. Interestingly, also mitochondrial factors are strongly enriched with LLPS FUS, providing a potential explanation for the observed changes in mitochondrial gene expression in mouse models of ALS-FUS. In summary, we present a methodology to investigate the interactomes of phase separating proteins and provide evidence that LLPS shapes the FUS interactome with implications for function and disease

Adult hippocampal neurogenesis as a target for cocaine addiction: a review of recent developments

Author manuscriptBasic research in rodents has shown that adult hippocampal neurogenesis (AHN) plays a key role in neuropsychiatric disorders that compromise hippocampal functioning. The discovery that dependence-inducing drugs regulate AHN has led to escalating interest in the potential involvement of AHN in drug addiction over the last decade, with cocaine being one of the most frequently investigated drugs. This review argues that, unlike other drugs of abuse, preclinical evidence does not, overall, support that cocaine induces a marked or persistent impairment in AHN. Nevertheless, experimental reduction of AHN consistently exacerbates vulnerability to cocaine. Interestingly, preliminary evidence suggests that, on the contrary, increasing AHN might help both to prevent and treat addiction.This study was funded by grants from the Spanish Ministry of Economy and Competitiveness (MINECO, Agencia Estatal de Investigación) cofounded by the European Regional Development Fund -AEI/FEDER, UE- (‘Jóvenes Investigadores grant’ PSI2015-73156-JIN to E.C.O.; and PSI2017-82604R to L.J.S.)

Study of advanced railgun hydrogen pellet injectors for fusion reactor refueling

An advanced railgun system has been developed to assess its feasibility as a hypervelocity hydrogen pellet injector for magnetically confined plasmas. It consists of a pellet generator/gas gun assembly for freezing hydrogen pellets and injecting them into the railgun at velocities as high as 1.5 km/s. A plasma armature is formed by ionizing the low-Z propellant gas behind the pellet and firing the railgun. This fuseless operation prevents high-Z impurities from entering the reactor during pellet injection.The railgun system has several features that distinguish it from its predecessors, including: (1) a more compact, versatile pellet generator, (2) a new gas gun configuration that produces significantly higher pellet speeds, (3) a perforated coupling piece between the gas gun and railgun to prevent spurious arcing, and (4) ablation-resistant sidewalls, perforated sidewalls and transaugmentation to reduce inertial and viscous drag, the primary obstacles to achieving hypervelocity.A unique system of sophisticated controls and diagnostics has been assembled to operate the railgun system and assess its performance, including fully automated pellet freezing and gas gun operation, an automatic timing circuit that is immune to mistriggering caused by pellet fragmentation or electromagnetic interference, a streak camera, photostations, light gates, current trans formers, B-dot probes, laser interferometry and optical spectroscopy.Free-arc and hydrogen pellet experiments were conducted to evaluate various railgun designs. Transaugmented and simple railguns 1.2 and 2 m long were tested. The performances of railguns using Mullite, solid Lexan and perforated Lexan sidewalls were compared. The railgun theory of operation and anticipated losses are also examined. The theoretical predictions are found to be in good agreement with the experimental results.The advanced railgun system has set several world records for bare hydrogen pellet velocity, including a 3.3 km/s shot on the 2 m gun, thus demonstrating that railguns are viable candidates for high speed pellet injection.U of I OnlyETDs are only available to UIUC Users without author permissio

Role of adult hippocampal neurogenesis in stress resilience

There is a growing appreciation that adult hippocampal neurogenesis plays a role in emotional and cognitive processes related to psychiatric disorders. Although many studies have investigated the effects of stress on adult hippocampal neurogenesis, most have not focused on whether stress-induced changes in neurogenesis occur specifically in animals that are more resilient or more susceptible to the behavioural and neuroendocrine effects of stress. Thus, in the present review we explore whether there is a clear relationship between stress-induced changes in adult hippocampal neurogenesis, stress resilience and antidepressant-induced recovery from stress-induced changes in behaviour. Exposure to different stressors is known to reduce adult hippocampal neurogenesis, but some stressors have also been shown to exert opposite effects. Ablation of neurogenesis does not lead to a depressive phenotype, but it can enhance responsiveness to stress and affect stress susceptibility. Monoaminergic-targeted antidepressants, environmental enrichment and adrenalectomy are beneficial for reversing stress-induced changes in behaviour and have been shown to do so in a neurogenesis-dependant manner. In addition, stress and antidepressants can affect hippocampal neurogenesis, preferentially in the ventral hippocampus. Together, these data show that adult hippocampal neurogenesis may play a role in the neuroendocrine and behavioural responses to stress, although it is not yet fully clear under which circumstances neurogenesis promotes resilience or susceptibility to stress. It will be important that future studies carefully examine how adult hippocampal neurogenesis can contribute to stress resilience/susceptibility so that it may be appropriately exploited for the development of new and more effective treatments for stress-related psychiatric disorders

Desenvolvimento do controle cervical em crianças com paralisia cerebral

RESUMOO controle cervical é uma das primeiras aquisições motoras voluntária da criança. A disfunção motora na Paralisia cerebral pode ocasionar atraso no desenvolvimento do controle cervical e fixação de padrões posturais patológicos. O objetivo deste estudo foi de identificar os recursos disponíveis na literatura para aquisição do controle cervical e relacioná-los com o caso de uma criança que apresenta severo atraso do desenvolvimento motor. Foram avaliados os reflexos primitivos, as reações de retificação e equilíbrio, o grau de espasticidade, a função motora ampla e as habilidades funcionais. Observou-se presença de reflexos primitivos e espasticidade em todos os membros, deficiência ou ausência das reações de retificação e equilíbrio e limitação funcional muito severa. A obtenção de um desenvolvimento neuropsicomotor mais normal possível é o objetivo principal no tratamento de uma criança com paralisia cerebral. Observou-se escassez de estudos relacionados ao controle cervical, apesar de ser um precursor necessário para outras aquisições motoras e posturais