Search results for "OLFACTORY"

The generation of oligodendroglial cells is preserved in the rostral migratory stream during aging

2013

The subventricular zone (SVZ) is the largest source of newly generated cells in the adult mammalian brain. SVZ-derived neuroblasts migrate via the rostral migratory stream (RMS) to the olfactory bulb (OB), where they differentiate into mature neurons. Additionally, a small proportion of SVZ-derived cells contribute to the generation of myelinating oligodendrocytes. The production of new cells in the SVZ decreases during aging, affecting the incorporation of new neurons into the OB. However, the age-related changes that occur across the RMS are not fully understood. In this study we evaluate how aging affects the cellular organization of migrating neuroblast chains, the proliferation, and th…

Sensory preconditioning in newborn rabbits: from common to distinct odor memories.

2013

Brief Communication; International audience; This study evaluated whether olfactory preconditioning is functional in newborn rabbits and based on joined or independent memory of odorants. First, after exposure to odorants A+B, the conditioning of A led to high responsiveness to odorant B. Second, responsiveness to B persisted after amnesia of A. Third, preconditioning was also functional with two overlapping pairs of odorants (A+B and B+C) and amnesia of one odorant did not affect memory of the others. Thus, incidental pairing of odorants allows reinforcement of one odorant to implicitly reinforce the others, the bond then vanishes, and the memory of each element becomes independent.

ELECTRONIC OLFACTORY SYSTEM TO EVALUATE THE FRUIT QUALITY

2012

Attracted or repelled?--a matter of two neurons, one pheromone binding protein, and a chiral center.

1998

Abstract Two species of scarab beetles, the Osaka beetle (Anomala osakana) and the Japanese beetle (Popillia japonica), utilize the opposite enantiomers of japonilure, (Z)-5-(1-decenyl)oxacyclopentan-2-one, as their sex pheromones. Each species produces only one of the enantiomers that functions as its own sex pheromone and as a very strong behavioral antagonist for the other species. Using an integrated approach we tested whether the discrimination of these two opposite signals is due to selective filtering by pheromone binding proteins or whether it originates in the specificity of ligand–receptor interactions. We found that the antennae of each of these two scarab species contain only a …

Influence of composition(CO2 and Sugar) on aroma release and perception of mint-flavored carbonated beverages

2009

The aim of the present work was to identify and quantify physical mechanisms responsible for in-nose aroma release during the consumption of mint-flavored carbonated beverages in order to better understand how they are perceived. The effect of two composition factors (sugar and CO(2)) was investigated on both the sensory and physicochemical properties of drinks by studying in vitro and in vivo aroma release. Sensory results revealed that the presence of CO(2) increased aroma perception regardless of the sugar content. In agreement with volatility parameters, in vivo measurements showed that carbonated drinks released a greater quantity of aroma compounds in the nose space than non-carbonate…

Sur la piste du « goût du gras »

2006

Sense of taste informs the body about the quality of ingested foods. Five sub-modalities allowing the perception of sweet, salty, sour, bitter, and umami stimuli are classically depicted in Human. However, the spontaneous attraction of mammals for fatty foods raises the possibility of an additional oro-sensory modality devoted to the fat perception. During a long time, oro-sensory perception of dietary lipids was thought to take place only through textural and retronasal olfactory cues. This minireview analyses recent findings showing that the gustation can also play a significant role in the dietary lipid perception.

Defective Postnatal Neurogenesis and Disorganization of the Rostral Migratory Stream in Absence of theVax1Homeobox Gene

2004

The subventricular zone (SVZ) is one of the sources of adult neural stem cells (ANSCs) in the mouse brain. Precursor cells proliferate in the SVZ and migrate through the rostral migratory stream (RMS) to the olfactory bulb (OB), where they differentiate into granule and periglomerular cells. Few transcription factors are known to be responsible for regulating NSC proliferation, migration, and differentiation processes; even fewer have been found to be responsible for the organization of the SVZ and RMS. For this reason, we studied the ventral anterior homeobox (Vax1) gene in NSC proliferation and in SVZ organization. We found thatVax1is strongly expressed in the SVZ and in the RMS and that,…

Modulation of higher-order olfaction components on executive functions in humans

2015

The prefrontal (PFC) and orbitofrontal cortex (OFC) appear to be associated with both executive functions and olfaction. However, there is little data relating olfactory processing and executive functions in humans. The present study aimed at exploring the role of olfaction on executive functioning, making a distinction between primary and more cognitive aspects of olfaction. Three executive tasks of similar difficulty were used. One was used to assess hot executive functions (Iowa Gambling Task-IGT), and two as a measure of cold executive functioning (Stroop Colour and Word Test-SCWT and Wisconsin Card Sorting Test-WCST). Sixty two healthy participants were included: 31 with normosmia and …

Postnatal Neurogenesis and Neuronal Regeneration

2004

The discovery of neurogenesis in the adult brain has challenged one of the central dogmas of neuroscience. Pioneer reports in rodents seed the ground for a detailed description in birds and reptiles, which was finally confirmed in discrete regions of several mammalian species including humans. This neurogenetical capability may serve as the basis for neuronal regeneration, as has already been described in the reptilian brain, and thus may represent a promising therapeutic approach. Consequently, in the last years there has been an important effort to deepen our knowledge of the biology, the functional significance and the regulation of adult neurogenesis.

Multipotent Neural Stem Cells Reside into the Rostral Extension and Olfactory Bulb of Adult Rodents

2002

The lateral walls of the forebrain lateral ventricles are the richest source of stem cells in the adult mammalian brain. These stem cells give rise to new olfactory neurons that are renewed throughout life. The neurons originate in the subventricular zone (SVZ), migrate within the rostral extension (RE) of the SVZ along the rostral migratory stream (RMS) within tube-like structures formed of glial cells, to eventually reach the olfactory bulb (OB). We demonstrate that, contrary to the current view, multipotential (neuronal-astroglial-oligodendroglial) precursors with stem cell features can be isolated not only from the SVZ but also from the entire RE, including the distal portion within the…