NCube/papyrus huggingface dataset:
Identification des difficultés fonctionnelles dans le trouble cognitif léger : perspective des ergothérapeutes

Mild cognitive impairment (MCI) is a transitional stage between aging and dementia. The current diagnostic criteria consider that MCI mainly causes difficulties on a cognitive level. However, recent studies have shown that MCI also impact an individual’s functions that can alter their independence in instrumental activities of daily living (IADL), i.e. activities that allows them to be independent within their community. Faced with this lack of consensus in writing, this research aims to explore the perspective of occupational therapists regarding the functional impact of MCI by using an online survey. As occupational therapists are experts in the field, the survey aims to deepen our knowledge of MCI, based on the clinical practice of these health professionals. The survey, which was done in French, was developed based on a quick literature review on the topic and consultations with two experts in the field. The survey was sent to the occupational therapists of the province of Quebec through their professional order and through social media. The results have been analyzed by descriptive and statistical analysis. The results of the survey, which was completed by 233 occupational therapists, revealed that the respondents agree on the fact that there is a presence of functional impairment within MCI; 84 % of the respondents identified that the IADL are being affected by the disease. However, 24,4% mentioned that basic activities were equally affected, which does not match with the current scientific writing. Few respondents were familiar with TCL subtypes (14.5%) and the vast majority (78%) use cognitive screening tests with this clientele as their main source of investigation. In conclusion, the occupational therapists have a general knowledge on the scientific results on the MCI, but as shown in the writing their practices reflect the absence of a consensus. Keywords: Mild cognitive impairment, Dementia, Activities of daily living, Functional difficulty, Occupational Therapy

Keyphrases: Mild cognitive impairment, Dementia, Activities of daily living, Functional difficulty, Occupational therapy
The role of pericytes in the regulation of retinal microvasculature dynamics in health and disease

Pericytes are contractile cells that wrap along the walls of capillaries. In the brain, pericytes play a crucial role in the regulation of capillary diameter and vascular blood flow in response to metabolic demand. It has been suggested that, during brain ischemia, pericytes constrict the capillaries, which remain constricted even after reperfusion resulting in impaired microcirculatory blood flow. Despite this, little is known about the role of pericytes in brain and retinal diseases and their contribution to capillary dynamics and local blood flow. To better understand the response of capillaries and pericytes during ischemic injury in the retina, and to identify the molecular mechanisms of pericyte-mediated capillary constriction, we characterized the response of pericytes during transient retinal ischemia ex vivo and in vivo. We demonstrated that ischemia leads to anomalous microvascular changes characterized by a marked reduction in capillary diameter. This response was accompanied by an increase in the number of capillary constrictions at pericyte locations suggesting that ischemia promotes rapid pericyte constriction on retinal capillaries leading to microvascular dysfunction. Lastly, we show that ischemia increases intracellular calcium in pericytes suggesting that pericyte contraction leading to capillary constriction is a calcium-dependent process.

Keyphrases: Visual system, Retina, Neurovascular coupling, Pericyte, Capillaries, Blood flow, Ischemia, Vascular impairment, Live imaging, 2-photon microscopy, Circulation sanguine
Implication des cellules gliales dans la modulation de l’activité synaptique à la jonction neuromusculaire sénescente

Age-related muscle weakness is simply unavoidable, and it can severely compromise physical autonomy for elderlies in addition to increase the risk of fall-related injuries. One element underlying this motor decline is the degeneration of the neuromuscular junction (NMJ), the synaptic connection between motor neuron and muscle. Amongst other age-related events, frequent denervation of the motor axon terminal coupled with impaired compensatory mechanisms compromise NMJ function and integrity. Beside the synaptic alterations, properties changes have also been observed for Perisynaptic Schwann cells (PSCs), glial cells at this synapse. These glial changes could play key role in the degenerative events happening at the senescent NMJ, since PSCs are well known to be crucial at the mature NMJ by regulating synaptic function, maintenance and plasticity. Therefore, we hypothesized that impaired NMJ function may arise in part from age-related glial dysfunction. Using electrophysiological recordings, we characterized NMJs functionals properties of levator auris longus muscle from adult (3 months) CD1 mice, old (24 months) and very old (30 months). We observed preserved synaptic transmission properties with aging, along with profound synaptic plasticity alterations following high-frequency nerve stimulation. Particularly, we showed long-term synaptic plasticity is reversed in terms of polarity for both old and very old animals, going from synaptic potentiation to depression with age. To investigate PSCs contribution to this synaptic alteration, we adapted a strategy implicating single-cell electroporation to manipulate selectively glial calcium activity while simultaneously realizing electrophysiological recordings for 3 months and 24 months mice. This strategy revealed long-term synaptic plasticity alterations seem to be mediated in a Ca2+-dependent manner by PSCs. Using a specific pharmacological approach, we then showed long-term synaptic plasticity events are also dependents upon adenosine receptors activation, which are presynaptic effectors of glial-dependent plasticity. Altogether, these results suggest PSCs dysregulation seems to mediate in a purine-dependent manner age-related NMJ weakness. Thus, our study raises the possible implication of PSCs in NMJ’s age-related degeneration and it brings to light glial cells as a potential therapeutic target to prevent muscle weakness for elderlies.

Keyphrases: Interactions Neurone-glie, Aging, Neuromuscular Junction, Neuron-glia interactions, Perisynaptic Schwann cells, Synaptic Plasticity
Sommes-nous de bons juges de notre stress? Marqueurs subjectifs et physiologiques de stress chez de jeunes adultes se disant ‘zen’ versus très stressés

Until the early 1960s, the physiological and subjective dimensions of stress were studied independently. It is with the development of psychoneuroendocrine research domain that studies began to combine the two dimensions of stress within a single protocol. Surprisingly, even though 60 years have passed since the development of psychoneuroendocrinology, a fundamental question remains unanswered: "Are we good judges of our stress?” A lack of consideration in the literature for the chronic aspect of subjective stress may be central to this problem. Thus, the purpose of this thesis was to compare psychological markers of stress, stress reactivity and diurnal cortisol secretion in individuals feeling chronically 'very stressed out' or 'zen'. To do this, 60 adults aged between 18 and 35 were recruited with an auto-categorization method, i.e. participants were categorizing themselves into one of our two groups by answering to one of our two different ads seeking the recruitment of either 'very stressed out' or 'zen' individuals. Depressive symptomatology, trait anxiety and acute subjective stress were measured with questionnaires. Cardiac measures and salivary cortisol were collected while the participants were exposed to a psychosocial stressor, i.e. the Trier social stress test. Participants further had to collect saliva samples at home to measure diurnal cortisol (a stress hormone). The results show that auto-categorized subjective stress is a good predictor of levels of distress, but not of reactivity to a stressor. Nevertheless, the ‘zen’ individuals showed a significantly lower awakening cortisol response when compared to stressed out individuals. Our results confirm previous studies showing a lack of correlation between psychological and physiological markers  of stress and extend these data to the domain of chronic stress. These results underline the importance of implementing specific interventions targeting the subjective dimension of stress in educational programs aiming to reduce stress.

Keyphrases: Subjective stress, Physiological stress, Salivary cortisol, Cardiac measures, Cortisol awakening response, Stress reactivity
Régulation du réseau hippocampique par la plasticité synaptique mTORC1-dépendante des interneurones somatostatinergiques

Hippocampus is the main cerebral region within the brain that has a role in the learning process and by doing so has a crucial function in memory and spatial navigation. Long-term synaptic plasticity of principal cells is strongly established as a prime cellular substrate for hippocampal learning and memory. However, the contribution of inhibitory interneuron synaptic plasticity in hippocampal memory consolidation remain a major challenge. In this study, cell-type specific conditional knockout strategies were used to alter specifically in somatostatin interneurons (SOM-INs) Mechanistic Target of Rapamycin Complex 1 (mTORC1) activity, an important translational control mechanism in long-term synaptic plasticity. In the study, it is shown that it is possible to induce group I metabotropic glutamate receptor (mGluR1) and mTORC1 mediated late long-term potentiation (l-LTP) at excitatory input synapses onto SOM-INs by applying repetitive chemical induction of mGluR1. Furthermore, up- and down-regulation of SOM-INs mTORC1 activity bi-directionally regulated synaptic plasticity of feedback excitation of inhibitory interneurons. In addition, mTORC1-mediated late-LTP in SOM-INs regulated Schaffer collateral pathway LTP in pyramidal neurons. These findings uncover a functional role of synaptic plasticity at excitatory inputs onto SOM-INs in the regulation of hippocampal integration of information.

Keyphrases: mTORC1, mGluR1, hippocampus, synaptic plasticity, somatostatinergic interneurons, metaplasticity, learning and memory
Caractérisation des comorbidités psychiatriques et comportementales des enfants et des adolescents ayant subi une première crise épileptique

Objective: Epilepsy is a very common pediatric neurological disorder and about 4% of the general population will have an unprovoked epileptic seizure at least once in their lifetime. Of these, about 40% will experience a reoccurrence. Currently, except for the presence of an electroencephalogram (EEG) with epileptiform abnormalities and a structural-metabolic etiology, there are very few known factors to identify patients who will have a reoccurrence. Our hypothesis is that the presence of psychiatric and behavioral comorbidities in patients with a first seizure could be a determinant of reoccurrence. To answer this question, our study aims to identify the comorbidities present in this population and eventually to evaluate the influence of comorbidities on reoccurrence of seizures. Method: When a child was referred in neurology for a first paroxysmal episode, he underwent an EEG and a neurological evaluation. For the screening of comorbidities, parents completed questionnaires via a web platform (CHADIS). The questionnaires included the M-CHAT-R, SCQ, ASQ-3, CBCL, SCARED and CES-DC. Questionnaire scores were adjusted for age and sex and analyzed via a Kruskal-Wallis. The prevalence of comorbidities was analyzed via a chi-square and the risk of recurrence was assessed with time-to-event analysis. Results: The analysis of the 89 subjects aged between 1 month and 18 years (49 males, 40 females) showed significantly (p < 0.05) more comorbidities in the 37 patients with a first epileptic seizure (57%) and in the 27 patients with a non-epileptic episode (59%) compared to 25 healthy subjects (28%). The dominant comorbidity of patients was language delay. Patients had a significantly higher score in the Social Communication Questionnaire (SCQ) compared to healthy subjects (p = 0.013). The recurrence rate of our patients was 27%, but our results were inconclusive regarding the influence of comorbidities on the risk of reocurrence (RR = 1.03, 95% CI [0.24, 4.53]). Conclusion: This is the first study to test the influence of comorbidities on the risk of reoccurrence. Although our results are preliminary, this opens the door to identifying more risk factors for reoccurrence. The goal is to be able to start an early treatment to reduce the rate of reoccurrence and associated cognitive deficits.

Keyphrases: epilepsy, first seizure, convulsion, comorbidity, recurrence risk, pediatric population
Étude des qualités psychométriques du Mini-BESTest avec la clientèle lésée médullaire en réadaptation

People admitted to an inpatient rehabilitation hospital after spinal cord injury (SCI) often have a standing postural control impairment. The main objective was to evaluate the psychometric properties of a new balance assessment, the Mini-BESTest (MBT), in this clientele.  The clinical data of 60 people with SCI (prospective study: n=24; retrospective study: n=36), average age of 52 years, were used. The test-retest and inter-rater reliability were investigated for 23 participants able to stand 30 seconds without help. The MBT was administered twice at one- to two-day intervals at the beginning (n=12 participants) or at the end of rehabilitation (n=11). One of these two sessions was recorded to evaluate inter-rater reliability. In addition, these participants completed a questionnaire to rate their perception of the change in their standing balance during their rehabilitation. Results from several clinical tests allowed assessing other psychometric properties. Various statistical tests and recommended approaches were used. The significance level was set at 0.05.  The results showed excellent test-retest (CCI2,1 = 0.94) and inter-rater (CCI2,1 = 0.96) reliability. The minimal detectable change was 4 points. Correlations between the MBT and other balance and walking assessments (rs = ± 0.74 – 0.82) support the construct validity of the MBT, as does the significant discrimination between different groups. Changes in scores between the MBT pre- and post-rehabilitation assessments demonstrated sufficient internal responsiveness while external responsiveness was insufficient. The MBT demonstrated neither floor nor ceiling effect. Item #7 (feet together: eyes open, firm surface) was the easiest and could serve as an indicator for deciding whether or not to perform the MBT during rehabilitation. The overall results support the use of the MBT in a clinical environment to evaluate the standing postural control of people with SCI in inpatient rehabilitation.

Keyphrases: Rehabilitation, Spinal cord injury, Postural control, Balance, Walking, Clinical evaluation, Reliability, Validity, Responsiveness
Comparaison de la force musculaire des membres inférieurs, de l’équilibre, de la mobilité et de la fonction chez les femmes âgées avec incontinence urinaire d’urgence ou mixte et les femmes âgées sans incontinence

Context : After the age of 65, the prevalence of urinary incontinence (UI) is one in two women. A positive correlation between falls and urgency UI (UUI) or mixed UI (MUI) has been identified. However, lower-extremity impairments in older women with UUI/MUI have not been thoroughly investigated. The primary goal of this study was to compare lower limb strength, balance, mobility and function in older women with and without UUI/MUI. The secondary goal was to evaluate the association between these measurements and UI severity.  Methods : Forty older women with and without UUI/MUI completed standardized tests to gather data on UI symptoms (ICIQ-UI SF questionnaire) lower limb strength (knee flexor/extensor dynamometry, 30-Second Sit-to-Stand Test), balance (Single Leg Stance Test, Four Square Step Test, Activities-Specific-Balance-Confidence questionnaire), mobility (10-Meter Walk Test, 6-Minute Walk Test) and function (Human Activity Profile questionnaire, SF-12 questionnaire).  Results : Significant differences in balance and mobility were observed between groups.  Women with UI had shorter single leg stance times both on the dominant (p˂0.001) and non-dominant (p˂0.005) sides, lower balance confidence scores (p=0.01) and slower gait speeds (p=0.01). Women with UI also reported a significantly lower self-perceived health (p=0.01). No significant differences were observed in knee flexor/extensor strength and in function. No significant correlations were found between the severity of the UI symptoms reported by women with UI in the ICIQ-UI-SF and the measurements of lower limb muscle strength, balance, mobility or function  Conclusion : The results from this pilot study suggest balance and mobility impairments in high-functioning older women with UUI/MUI. More studies are needed to confirm these results. By reporting power calculation for sample size, this pilot study provides a useful basis to design and conduct larger studies.

Keyphrases: Mixed urinary incontinence, Urgency urinary incontinence, Women's health, Aging, Muscle strength, Balance, Mobility, Function
Méthode d'inférence par bootstrap pour l'estimateur sisVIVE en randomisation mendélienne

In the observational data framework, estimation must account for unmeasured confounders, which affect both exposure and outcome. The reason for this is that if the effect of confounders is not considered, the causal effect estimate will suffer from confounding bias. The econometrics literature addresses this problem by using the instrumental variables method, which enables causal inference when confounding is present by using variables which have the property of being "random" in the posited model and strongly associated with the exposure. Hence, they can serve as instruments to randomize exposure, thus mimicking the setting of randomized control trials—the gold standard to establish causality. With genetic data, the issue can be approached similarly using Mendelian randomization. Mendelian randomization studies apply the instrumental variables approach to genetics by exploiting the natural randomness of allele allocation and using single-nucleotide polymorphisms (SNPs) as instrumental variables to obtain a "quasi-randomized" exposure phenotype. However, the choice of SNPs is not arbitrary; instead, it relies on a set of assumptions for validity, some of which cannot be verified in most empirical settings. When using multiple SNPs as instruments, one might be tempted to use the widely known two-stage least squares estimator, given its simplicity. Yet, the use of this estimator comes at the high price of assuming that all SNPs verify the set of assumptions, whereas in reality, SNPs can be invalid, for instance, due to pleiotropy. To include the possibility that some SNPs may be invalid, Kang et al. (2014) proposed the sisVIVE estimator, which mitigates the effect of invalid SNPs up to a threshold of 50% of invalid SNPs, thereby providing a point estimate of the causal effect. We add to their contribution by exploring a bootstrap method to construct confidence intervals for sisVIVE. Results obtained from simulations and an application to a real dataset from the Montreal Heart Institute's Biobank are presented.

Keyphrases: variable instrumentale, sisVIVE, bootstrap, Causal inference, Genetics, Confounding bias, Pleiotropy, Mendelian randomization, Instrumental variable, Confidence interval, Biobank
Sur le h-principe pour les immersions coisotropes et les classes caractéristiques associées

This master’s thesis is concerned with symplectic vector bundles and their special subbundles. In the first chapter, we will recall the definition of those bundles and will show a fundamental result which reduces the study of symplectic vector bundles to the one of complex vector bundles. This result will also be crucial for the exposition of symplectic topology in the next chapter. The second chapter serves as a broad exposition of symplectic topology for those unfamiliar with the subject and thus, is fairly independent from the others. However, the chapter greatly helps to understand how the results of the subsequent chapters fit in the whole of symplectic topology. In the third chapter, we will recall some notions necessary to the understanding of h-principles and enunciate the theorem that will be important to us for the rest of the thesis. The fourth chapter will revisit the work of Lalonde in [17] and [16] on isotropic characteristic classes. Those cohomology classes appear in the study of isotropic immersions into the standard symplectic space (R2n;!0) thanks to a form of the previously introduced h-principle. Finally, the fifth and last chapter of this master’s thesis will use the ideas of the previous chapter in order to define coisotropic characteristic classes, which will appear in the study of coisotropic immersions thanks to another h-principle in the same family. Those classes will turn out to be the same as their isotropic counterpart and thus, will not detect the differences that exist between the isotropic and coisotropic h-principles. A discussion of these differences will serve as a closer to the chapter.

Keyphrases: Symplectic vector bundle, Symplectic topology, Caracteristic classes, h-principle, Isotropic immersions, Coisotropic immersions
Les collocations du champ sémantique des émotions en mandarin

Collocations are recurrent across languages. They are arbitrary associations of words where one is freely chosen, while the other is chosen as a function of the first. Because of their arbitrary aspect, collocations that express the same meaning can vary greatly from one language to another. Explanatory and combinatorial lexicology [=ECL] (Mel’čuk et al., 1995) uses a formal tool, lexical functions, to describe collocations in several languages. However, there is still no dictionary of Mandarin that describes collocations systematically by means of lexical functions. This dissertation presents a model of a collocation dictionary of Mandarin within the framework of explanatory and combinatorial lexicology. From entries in the field of emotions picked from DiCoLiLex in French, we establish a corresponding nomenclature in Mandarin and extract from a corpus the cooccurrents of the lexical units under study to find collocations, using various statistical methods. Then, we adapt the microstructure of the dictionary to the characteristics of Mandarin in order to facilitate the lexicological description of the lexical units in the Chinese nomenclature. Finally, we discuss difficult cases encountered during the process and show that some phenomena do not fit well in the theory and propose possible solutions.

Keyphrases: Collocations, Mandarin, Lexicography, Explanatory and combinatorial lexicology, Lexical functions, Emotions