Histoire évolutive de la maladie carieuse : exemple des populations inuites

La maladie carieuse est une pathologie considérée comme le troisième fléau mondial par l’Organisation Mondiale de la Santé, puisqu’elle touche plus de 99 % des adultes. Historiquement, en Europe, la prévalence carieuse augmente progressivement depuis le Néolithique jusqu’à atteindre un pic au XXe siècle et ne commence à diminuer que depuis les 25 dernières années. Cependant, cette maladie n’a pas connu la même histoire évolutive dans toutes les populations humaines. Dans le cadre d’une thèse,..

Microsome-associated proteome modifications of Arabidopsis seedlings grown on board the International Space Station reveal the possible effect on plants of space stresses other than microgravity

11p.-2 fig.-6 tab.Growing plants in space for using them in bioregenerative life support systems during long-term human spaceflights needs improvement of our knowledge in how plants can adapt to space growth conditions. In a previous study performed on board the International Space Station (GENARA A experiment STS-132) we evaluate the global changes that microgravity can exert on the membrane proteome of Arabidopsis seedlings. Here we report additional data from this space experiment, taking advantage of the availability in the EMCS of a centrifuge to evaluate the effects of cues other than microgravity on the relative distribution of membrane proteins. Among the 1484 membrane proteins quantified, 227 proteins displayed no abundance differences between µ g and 1 g in space, while their abundances significantly differed between 1 g in space and 1 g on ground. A majority of these proteins (176) were over-represented in space samples and mainly belong to families corresponding to protein synthesis, degradation, transport, lipid metabolism, or ribosomal proteins. In the remaining set of 51 proteins that were under-represented in membranes, aquaporins and chloroplastic proteins are majority. These sets of proteins clearly appear as indicators of plant physiological processes affected in space by stressful factors others than microgravity.The authors would like to thank the National Aeronautics and Space Administration (NASA) who successfully performed the spaceflight experiment; they also thank the astronauts for performing the required tasks on board the ISS. We acknowledge the Norwegian User Support and Operations Center team (NUSOC) for the ground and space preparation of the GENARA-A experiment and we thank the European Aeronautic Defense and Space Company (Astrium EADS) for the design and building of the hardware. We also thank the European Space Agency (ESA) and the Centre National d’Etudes Spatiales(CNES) for their scientific and financial support.Peer reviewe

Contribution de l’anthropologie sensorielle à l’étude du COVID-19

En réponse à la pandémie COVID-19, de nombreux gouvernements ont pris des mesures sans précédent pour éviter un engorgement des unités de réanimation. En raison du lourd impact sociétal et économique de ces initiatives, des indicateurs épidémiologiques précis de la propagation de la maladie sont essentiels aux autorités de santé publique. Dans le même temps, la perturbation des perceptions des odeurs et du goût ont été identifiés comme l’un des symptômes les plus spécifiques de la maladie COV..

Smell and taste changes are early indicators of the COVID-19 pandemic and political decision effectiveness

In response to the COVID-19 pandemic, many governments have taken drastic measures to avoid an overflow of intensive care units. Accurate metrics of disease spread are critical for the reopening strategies. Here, we show that self-reports of smell/taste changes are more closely associated with hospital overload and are earlier markers of the spread of infection of SARS-CoV-2 than current governmental indicators. We also report a decrease in self-reports of new onset smell/taste changes as early as 5 days after lockdown enforcement. Cross-country comparisons demonstrate that countries that adopted the most stringent lockdown measures had faster declines in new reports of smell/taste changes following lockdown than a country that adopted less stringent lockdown measures. We propose that an increase in the incidence of sudden smell and taste change in the general population may be used as an indicator of COVID-19 spread in the population

Recent smell loss is the best predictor of COVID-19 among individuals with recent respiratory symptoms

In a preregistered, cross-sectional study we investigated whether olfactory loss is a reliable predictor of COVID-19 using a crowdsourced questionnaire in 23 languages to assess symptoms in individuals self-reporting recent respiratory illness. We quantified changes in chemosensory abilities during the course of the respiratory illness using 0-100 visual analog scales (VAS) for participants reporting a positive (C19+; n=4148) or negative (C19-; n=546) COVID-19 laboratory test outcome. Logistic regression models identified univariate and multivariate predictors of COVID-19 status and post-COVID-19 olfactory recovery. Both C19+ and C19- groups exhibited smell loss, but it was significantly larger in C19+ participants (mean±SD, C19+: -82.5±27.2 points; C19-: -59.8±37.7). Smell loss during illness was the best predictor of COVID-19 in both univariate and multivariate models (ROC AUC=0.72). Additional variables provide negligible model improvement. VAS ratings of smell loss were more predictive than binary chemosensory yes/no-questions or other cardinal symptoms (e.g., fever). Olfactory recovery within 40 days of respiratory symptom onset was reported for ~50% of participants and was best predicted by time since respiratory symptom onset. We find that quantified smell loss is the best predictor of COVID-19 amongst those with symptoms of respiratory illness. To aid clinicians and contact tracers in identifying individuals with a high likelihood of having COVID-19, we propose a novel 0-10 scale to screen for recent olfactory loss, the ODoR-19. We find that numeric ratings ≤2 indicate high odds of symptomatic COVID-19 (4<10). Once independently validated, this tool could be deployed when viral lab tests are impractical or unavailable

More Than Smell—COVID-19 Is Associated With Severe Impairment of Smell, Taste, and Chemesthesis

Correction: Chemical Senses, Volume 46, 2021, bjab050, https://doi.org/10.1093/chemse/bjab050 Published: 08 December 2021Recent anecdotal and scientific reports have provided evidence of a link between COVID-19 and chemosensory impairments, such as anosmia. However, these reports have downplayed or failed to distinguish potential effects on taste, ignored chemesthesis, and generally lacked quantitative measurements. Here, we report the development, implementation, and initial results of a multilingual, international questionnaire to assess self-reported quantity and quality of perception in 3 distinct chemosensory modalities (smell, taste, and chemesthesis) before and during COVID-19. In the first 11 days after questionnaire launch, 4039 participants (2913 women, 1118 men, and 8 others, aged 19-79) reported a COVID-19 diagnosis either via laboratory tests or clinical assessment. Importantly, smell, taste, and chemesthetic function were each significantly reduced compared to their status before the disease. Difference scores (maximum possible change +/- 100) revealed a mean reduction of smell (-79.7 +/- 28.7, mean +/- standard deviation), taste (-69.0 +/- 32.6), and chemesthetic (-37.3 +/- 36.2) function during COVID-19. Qualitative changes in olfactory ability (parosmia and phantosmia) were relatively rare and correlated with smell loss. Importantly, perceived nasal obstruction did not account for smell loss. Furthermore, chemosensory impairments were similar between participants in the laboratory test and clinical assessment groups. These results show that COVID-19-associated chemosensory impairment is not limited to smell but also affects taste and chemesthesis.The multimodal impact of COVID-19 and the lack of perceived nasal obstruction suggest that severe acute respiratory syndrome coronavirus strain 2 (SARS-CoV-2) infection may disrupt sensory-neural mechanisms.Peer reviewe

Cytosolic calcium increases in response to a change in the positioning of gravisensors: results from space experiments.

Plants are the ability to sense and to re-orient their growth in response to various stimuli including light, gravity, wind and humidity. The response of a plant organ to the change of gravity direction called gravitropism can be regarded as a crucial factor in the posture control of stems (Moulia and Fournier, 2009) and in the progression for roots into the soil (Roy and Basshamm, 2014). In roots, specialized sensory cells, called statocytes, located in the root apex, perceive signal gravity. Even if it is well known that amyloplasts (located in the statocytes) are considered as gravisensors, the role of these organelles on transduction pathways, is not clearly elucidated (Perbal and Driss-Ecole, 2003). Some studies have demonstrated that cytoplasmic free Ca2+ concentration ([Ca2+]cyt) is affected by environmental stimuli including gravity (for review, Tatsumi et al., 2014). The regulation of this homeostasis involves a series of transduction events such as the synthesis and activation of calcium binding and targeted proteins including calmodulin proteins

Plants in space: GRAVI-2 experiment

The Gravi-2 experiment was launched on flight SpaceX3 in April 2014 (http://lensesinspace.wordpress.com/) and was performed on-board the ISS in May 2014 with EMCS (European Modular Cultivation System).Gravity is considered to be an important environmental factor in the orientation of plant growth. In the case of roots, signal gravity is perceived by specialized cells located in the root apex and, so called statocytes. Even if it is well known that the movements of amyloplasts (located in the statocytes) induce a series of signalling pathways, the role of amyloplasts displacement is not clearly elucidated. The objective of the GRAVI-2 project is to study the impact of amyloplasts displacement on the calcium-dependant pathways and thus, better understanding the gravity perception in lentil roots. The Gravi-2 experiment was launched on flight SpaceX3 in April 2014 (http://lensesinspace.wordpress.com/) and was performed on-board the ISS in May 2014 with EMCS (European Modular Cultivation System). Lentil seeds were germinated on the International Space Station (ISS) in different situations: (1) continuously in microgravity conditions (e.g. 10-4 g), (2) 10-2 g during 8 hours after a growth period of 23 hours in microgravity, (3) 2g during 5 minutes after a growth period of around 31 hours in microgravity, and (4) 2g during 15 minutes after a growth period of around 31 hours in microgravity. The studies will be performed using complementary approaches including the analysis of amyloplast positioning, calcium localisation and the level of expression of genes

Evolutionary perspectives of high resolution three-dimensional comparisons of bony labyrinths in humans, chimpanzees and baboons

International audienceThe bony labyrinth consists of three parts (the two vestibular sacs, the three semicircular canals and the cochlea) and houses two functional systems. The vestibular system provides one way of motion detection in a three-dimensional space. The cochlea is specialized for sound detection. The close anatomical relationship between the bony labyrinth and the corresponding receptor endorgans provides an opportunity to study osteological specimens (including fossils). The investigation of the three-dimensional (3D) anatomical variation of the bony labyrinth in extant species represents a prerequisite for the interpretation of their fossil closest relatives. This prerequisite has not been completely fulfilled yet due to (i) the 3D geometry complexity of the labyrinth ; (ii) the difficulty to acquire high resolution data ; (iii) the few proposed expert-independent comparative methods. Here, we use 3D geometrical models of 40 bony labyrinths reconstructed from micro-CT scans of extant humans, chimpanzees, bonobos and baboons. We use recently developed automated computational tools allowing to process 3D free-form surfaces, and more specifically to assess the mean anatomy within a sample, the pattern of variability around this mean, and to compare samples. Our results allow us to identify the most common features and most striking differences within and between species. The use of such automated, 3D and objective techniques, coupled with standard linear, surface or volume measurements, may allow to gain further insight into the co-evolution of the two functional systems housed in the inner ear of the extant and extinct higher primates