Attentive monitoring of multiple video streams driven by a Bayesian foraging strategy

In this paper we shall consider the problem of deploying attention to subsets of the video streams for collating the most relevant data and information of interest related to a given task. We formalize this monitoring problem as a foraging problem. We propose a probabilistic framework to model observer's attentive behavior as the behavior of a forager. The forager, moment to moment, focuses its attention on the most informative stream/camera, detects interesting objects or activities, or switches to a more profitable stream. The approach proposed here is suitable to be exploited for multi-stream video summarization. Meanwhile, it can serve as a preliminary step for more sophisticated video surveillance, e.g. activity and behavior analysis. Experimental results achieved on the UCR Videoweb Activities Dataset, a publicly available dataset, are presented to illustrate the utility of the proposed technique.Comment: Accepted to IEEE Transactions on Image Processin

Through the Microbial Looking Glass: Premature Labor, Preeclampsia, and Gestational Diabetes: A Scoping Review

The influence of microbial factors on adverse perinatal outcomes has become the focal point of recent investigations, with particular interest in the role of the microbiome and probiotic interventions. The purpose of this scoping review was to identify and critique the most recent evidence about these factors as they relate to pregnancies complicated by preeclampsia (PEC), preterm birth (PTB), and gestational diabetes mellitus (GDM). Four databases (PubMed, EMBASE, Web of Science, and Cochrane) were searched for articles published in English in the last 10 years with the concepts of the microbiome, probiotics, and PEC, PTB, or GDM. Forty-nine articles were eligible for full-text review. Five articles were excluded, leaving 44 articles that met all the eligibility criteria. The relationships between the microbiome and the risk for PEC, PTB, and GDM are not fully elucidated, although probiotic interventions seem beneficial in decreasing PEC and GDM risk. Probiotic interventions targeting bacterial vaginosis and elimination of infection in women at risk for PTB appear to be beneficial. More research is needed to understand the contributions of the microbiome to adverse perinatal outcomes. Probiotic interventions appear to be effective in reducing risk for select outcomes

The endocannabinoid system controls food intake via olfactory processes

Comment in Sensory systems: the hungry sense. [Nat Rev Neurosci. 2014] Inhaling: endocannabinoids and food intake. [Nat Neurosci. 2014]; International audience; Hunger arouses sensory perception, eventually leading to an increase in food intake, but the underlying mechanisms remain poorly understood. We found that cannabinoid type-1 (CB1) receptors promote food intake in fasted mice by increasing odor detection. CB1 receptors were abundantly expressed on axon terminals of centrifugal cortical glutamatergic neurons that project to inhibitory granule cells of the main olfactory bulb (MOB). Local pharmacological and genetic manipulations revealed that endocannabinoids and exogenous cannabinoids increased odor detection and food intake in fasted mice by decreasing excitatory drive from olfactory cortex areas to the MOB. Consistently, cannabinoid agonists dampened in vivo optogenetically stimulated excitatory transmission in the same circuit. Our data indicate that cortical feedback projections to the MOB crucially regulate food intake via CB1 receptor signaling, linking the feeling of hunger to stronger odor processing. Thus, CB1 receptor-dependent control of cortical feedback projections in olfactory circuits couples internal states to perception and behavior

Effect of supplementation with different fat sources on the mechanisms involved in reproductive performance in lactating dairy cattle

peer reviewedSupplementary fat positively influences reproductive performance in dairy cattle, although the mechanisms involved are not clearly defined. Our objective was to determine the effects of four different fat supplements on follicle development, plasma steroid hormone concentrations and prostaglandin (PG) synthesis in lactating dairy cattle. Forty-eight early lactation Holstein-Friesian cows (21 primiparous, 27 multiparous) were used in a completely randomized block design. Cows were fed the same basal TMR diet and received one of four fat supplements: (i) palmitic acid (18:0 fatty acid; Control), (ii) flaxseed (rich in 18:3 n-3 fatty acid; Flax), (iii) conjugated linoleic acid (a mixture of cis-9, trans-11 and trans-10, cis-12 isomers; CLA), and (iv) fish oil (rich in 20:5 and 22:6 n-3 fatty acids; FO). All lipid supplements were formulated to be isolipidic; palmitic acid was added as necessary to provide a total lipid supplement intake of 500 g/day. Cows were synchronized to be in estrus on Day 15 of dietary treatment. All antral follicles were counted, and dominant follicles, subordinate follicles and corpora lutea were measured daily via transrectal ovarian ultrasonography for one complete estrous cycle. Blood samples were collected daily, and selected samples were analyzed for progesterone, estradiol, insulin-like growth factor-1, insulin, cholesterol and non-esterified fatty acids. Estrus was synchronized a second time, and liver and endometrial biopsies were collected on Day 7 of the estrous cycle. Gene expression was evaluated for a number of genes involved in prostaglandin synthesis (endometrium) and fatty acid uptake and utilization (liver). Fat supplementation had little effect on follicle development. Cows receiving supplementary n-3 fatty acids had lesser plasma progesterone (P4) and smaller corpora lutea than cows receiving the CLA or Control supplements. Effects of fat supplementation on the endometrial expression of genes involved in PG synthesis were minor. Hepatic expression of SREBF1, ASCL1 and FABP1 was reduced by FO supplementation. Reduced plasma P4 in n-3 supplemented cows may lead to a suboptimal uterine environment for embryo development and hence reduced fertility compared to cows receiving the control or CLA supplements

Extra-oral Halitosis

Halitosis affects around 25% of the whole population and has a large social and economic impact. For the majority of patients suffering from bad breath, it causes embarrassment and affects their social communication and life. Dentists and periodontologists are the first-line professionals to be challenged with this problem, so they should be aware of the origin, the detection and the treatment of this pathology. But halitosis can be indicative of underlying diseases, requiring a multidisciplinary team approach. Depending on the place where it is originated, halitosis can be divided into intra-oral and extra-oral, whose treatment is much more complicated than for intra-oral halitosis. In this work, the origins of extra-oral halitosis were addressed, as well as the responsible sulfur compounds. Distinctive methods of detection of halitosis were focused and their advantages and disadvantages were highlighted. Gas differentiation methods as an auxiliary tool were emphasized in the diagnosis of halitosis type and, therefore, in its specific treatment. At last, different methods of treatment of extra-oral halitosis have been approached, from masking the bad breath to more invasive treatments.A halitose afeta aproximadamente 25% da população e tem um grande impacto social e económico. Para a maioria dos pacientes que sofrem de halitose, a patologia causa constrangimento e afeta a sua comunicação oral e qualidade de vida. Os médicos dentistas e periodontologistas são os primeiros profissionais a serem confrontados com este problema, pelo que devem dominar a deteção, diagnóstico e tratamento desta patologia. Mas a halitose pode ser indicativa de doenças mascaradas, sendo necessária a abordagem de uma equipa multidisciplinar. Dependendo do local de origem, a halitose pode ser dividida em intraoral ou extraoral, sendo o tratamento mais complicado na extraoral que na primeira. Neste trabalho foram abordadas as diversas origens da halitose extraoral, assim como os compostos sulfurados responsáveis. Distintos métodos de deteção da halitose foram focados e evidenciados as suas vantagens e desvantagens. Foram salientados métodos de diferenciação gasosa como ferramenta de auxílio no diagnóstico do tipo de halitose e, consequentemente, no seu tratamento específico. Por último, foram discriminados métodos de tratamento da halitose extraoral, desde técnicas para disfarçar o mau hálito até tratamentos mais invasivos

Investigating the physiological role of hypothalamic glucokinase in appetite and glucose homeostasis

The brain relies on glucose as a source of energy. Mechanisms that promote the taste-independent intake of glucose have been proposed but not demonstrated. The arcuate nucleus (ARC) of the hypothalamus plays a critical role in regulating energy homoeostasis. It acts as a metabolic sensing unit responding to diverse signals, including glucose, to regulate appetite. Glucokinase is a glucose-sensing enzyme expressed in the ARC. The work in this thesis aims to investigate the physiological role of ARC glucokinase in energy homoeostasis. Recombinant adeno-associated virus (rAAV) expressing the pancreatic form of rat glucokinase mRNA (rAAV-GKS) was stereotactically delivered to the ARC of male Wistar rats (iARC-GKS). This approach specifically increased glucokinase activity in the ARC as compared to control rats (iARC-GFP). Pharmacological and genetic increase in ARC glucokinase activity resulted in a significant increase in food intake. Longitudinal experiments demonstrated that this food intake resulted in a significant increase in body weight and adiposity on normal chow and high-energy diets. Further work demonstrated that ARC glucokinase specifically promotes the intake of glucose, but not of fructose, and that the orexigenic effect of ARC glucokinase is driven by specific increase in appetite for glucose. Similar changes in glucose appetite and food intake were demonstrated to occur with alterations in ARC ATP-sensitive potassium (KATP) channel activation. Glucose-stimulated NPY release was increased with increased ARC glucokinase activity. This suggests that ARC glucokinase mediates its orexigenic glucose appetite promoting effects in part via altered KATP channel activation and NPY release, which is consistent with previous work. This work identifies ARC glucokinase as a regulator of glucose appetite and glucose appetite as an important driver of food intake. ARC glucokinase may represent the brain mechanism regulating the taste-independent intake of glucose and may underlie the phenomena of ‘sweet tooth’ and ‘carbohydrate craving’

Identification and charcterization of novel signals regulating feeding behavior and energy balance : evidences indicating TFF2 as a novel potential therapeutic target for diet-induced obesity treatment

La recherche dans le domaine de l'obésité a énormément progressé pendant les dernières décennies et a apporté une contribution fondamentale à la compréhension des mécanismes biologiques et physiologiques impliqués, de même que leurs interactions avec l'environnement obésogène. Les études génétiques et génomiques ont mis en évidence les traits héréditaires majeurs qui peuvent causer ou prédisposer à l'accumulation excessive de gras corporel et ils ont stimulé la caractérisation de nombreux gènes codant pour des protéines impliquées dans la physiologie du bilan énergétique. Malgré le progrès considérable des connaissances, les pharmacotherapies actuelles ne démontrent pas d'effets suffisamment efficaces sur la perte persistante de poids, et sont souvent suivies par des effets secondaires importants. Le travail présenté dans cette thèse a comme objectif principal d'identifier et de caractériser de nouvelles cibles thérapeutiques pour le traitement et la prévention de l'obésité et des maladies métaboliques associées. Plus spécifiquement, nous avons concentré nos études sur les mécanismes précoces régulant la prise alimentaire et le métabolisme énergétique. Nous nous sommes premièrement intéressés aux changements métaboliques précoces qui surviennent avec la menopause et qui peuvent prédisposer au développement de l'obésité. Nous avons ainsi analysé les effets aigus de la prévalence androgénique sur l'expression génique du tissu adipeux rétro-péritonéal, chez un modèle murin de menopause. Nos résultats démontrent qu'une seule injection de dihydrotestostérone induit des changements significatifs dans le profil transcriptionnel du tissu adipeux. Enfin, l'expression augmentée de plusieurs transcrits myogéniques dans ce tissu témoigne de sa plasticité exceptionnelle, une qualité qui pourrait être exploitée à des fins thérapeutiques. Nous avons ensuite analysé les effets rapides que la consommation de repas à haute teneur lipidique cause sur la perception de la satiété chez la souris. Selon plusieurs évidences, obtenues chez des sujets humains de même que chez des modèles animaux, les repas riches en gras ont des effets réduits et retardés sur la perception de la satiété, comparativement aux glucides ou aux protéines. Ils peuvent donc favoriser la surconsommation passive d'énergie et, à long terme, l'accumulation de poids corporel. Nous avons utilisé la méthode de l'analyse sérielle de l'expression génique (SAGE) et étudié les changements transcriptionnels induits par un seul repas dans des tissus clés de la souris, comme l'estomac et l'hypothalamus. Nous avons ainsi identifié plusieurs nouveaux transcrits qui avaient été spécifiquement et rapidement régulés par le repas riche en gras. Un certain nombre de ces gènes a été sélectionné pour caractériser ultérieurement leur potentiel dans le développement de l'obésité induite par la diète (OID). Cette thèse présente la première caractérisation in vivo des rôles du gène trefoil factor family member 2 (Tff2) dans la régulation du bilan énergétique et l'OID. Chez les souris, la déficience du gène Tff2 a altéré significativement le comportement alimentaire, ainsi que la prise énergétique et la dépense d'énergie après douze semaines de diète riche en gras. En conclusion, les souris Tff2 KO étaient moins efficaces dans l'accumulation de l'énergie ingérée et, par conséquent, plus résistantes à l'OID par rapport aux souris normales. Les résultats obtenus dévoilent des rôles totalement nouveaux pour Tff2 et indiquent pour la première fois son implication dans la régulation du bilan énergétique. Les évidences ici décrites suggèrent que Tff2 pourrait être une cible optimale pour la conception de molécules pharmacologiques, qui contrôleraient simultanément plusieurs points critiques pour la régulation du poids corporel et le traitement de l'obésité