39 research outputs found
Identification and verification of heat shock protein 60 as a potential serum marker for colorectal cancer
Colorectal cancer (CRC) is a major public health issue worldwide, and novel tumor markers may contribute to its efficient management by helping in early detection, prognosis or surveillance of disease. The aim of our study was to identify new serum biomarkers for CRC, and we followed a phased biomarker discovery and validation process to obtain an accurate preliminary assessment of potential clinical utility. We compared colonic tumors and matched normal tissue from 15 CRC patients, using two-dimensional difference gel electrophoresis (2D-DIGE), and identified 17 proteins that had significant differential expression. These results were further confirmed by western blotting for heat shock protein (HSP) 60, glutathione-S-transferase Pi, α-enolase, T-complex protein 1 subunit ÎČ, and leukocyte elastase inhibitor, and by immunohistochemistry for HSP60. Using mAbs raised against HSP60, we developed a reliable (precision of 5â15%) and sensitive (0.3 ng·mLâ1) immunoassay for the detection of HSP60 in serum. Elevated levels of HSP60 were found in serum from CRC patients in two independent cohorts; the receiver-operating characteristic curve obtained in 112 patients with CRC and 90 healthy controls had an area under the curve (AUC) of 0.70, which was identical to the AUC of carcinoembryonic antigen. Combination of serum markers improved clinical performance: the AUC of a three-marker logistic regression model combining HSP60, carcinoembryonic antigen and carbohydrate antigen 19-9 reached 0.77. Serum HSP60 appeared to be more specific for late-stage CRC; therefore, future studies should evaluate its utility for determining prognosis or monitoring therapy rather than early detection
An object memory bias induced by communicative reference
In humans, a good proportion of knowledge, including knowledge about objects and object kinds, is acquired via social learning by direct communication from others. If communicative signals raise the expectation of social learning about objects, intrinsic (permanent) features that support object recognition are relevant to store into memory, while extrinsic (accidental) object properties can be ignored. We investigated this hypothesis by instructing participants to memorise shape-colour associations that constituted either an extrinsic object property (the colour of the box that contained the object, Experiment 1) or an intrinsic one (the colour of the object, Experiment 2). Compared to a non-communicative context, communicative presentation of the objects impaired participantsâ performance when they recalled extrinsic object properties, while their incidental memory of the intrinsic shape-colour associations was not affected. Communicative signals had no effect on performance when the task required the memorisation of intrinsic object properties. The negative effect of communicative reference on the memory of extrinsic properties was also confirmed in Experiment 3, where this property was object location. Such a memory bias suggests that referent objects in communication tend to be seen as representatives of their kind rather than as individuals
ACTIVITE PHYSIQUE ET VIEILLISSEMENT
CLERMONT FD-BCIU-Santé (631132104) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF
Predators, Prey and Habitat Structure: Can Key Conservation Areas and Early Signs of Population Collapse Be Detected in Neotropical Forests?
Tropical forests with a low human population and absence of large-scale deforestation provide unique opportunities to study successful conservation strategies, which should be based on adequate monitoring tools. This study explored the conservation status of a large predator, the jaguar, considered an indicator of the maintenance of how well ecological processes are maintained. We implemented an original integrative approach, exploring successive ecosystem status proxies, from habitats and responses to threats of predators and their prey, to canopy structure and forest biomass. Niche modeling allowed identification of more suitable habitats, significantly related to canopy height and forest biomass. Capture/recapture methods showed that jaguar density was higher in habitats identified as more suitable by the niche model. Surveys of ungulates, large rodents and birds also showed higher density where jaguars were more abundant. Although jaguar density does not allow early detection of overall vertebrate community collapse, a decrease in the abundance of large terrestrial birds was noted as good first evidence of disturbance. The most promising tool comes from easily acquired LiDAR data and radar images: a decrease in canopy roughness was closely associated with the disturbance of forests and associated decreasing vertebrate biomass. This mixed approach, focusing on an apex predator, ecological modeling and remote-sensing information, not only helps detect early population declines in large mammals, but is also useful to discuss the relevance of large predators as indicators and the efficiency of conservation measures. It can also be easily extrapolated and adapted in a timely manner, since important open-source data are increasingly available and relevant for large-scale and real-time monitoring of biodiversity
French Guiana study sites, with the protected areas.
<p>Protected areas: nature reserves and national parks, in green. Locations of the sites where camera-trap surveys were implemented (1, Montagne de Fer; 2, Counami; 3, Montagne de Kaw; 4, Nouragues) in light brown; locations of the areas where line-transects were implemented in dark brown; and jaguar habitats from less favorable (light grey) to more favorable (dark grey).</p
Field surveys required to assess abundance of ungulates and two frugivorous birds, based on 40 surveys (up), and the number of jaguars based on four study areas (down).
<p>Top: the r coefficient correlation shows the correlation between the stabilized abundance (sampling effort > 100 km) and abundance assessed with a lesser sampling effort. The correlation is derived from 40 surveys.</p
French Guiana more favorable habitats of prey.
<p>Protected areas: nature reserves and national parks, in green. Hatchings: area with Human Footprint Index < 15 (thresold value allowing maintenance of the abundance of most of prey species). Dark grey: forest areas with canopy roughness > 12, favoring higher biomass of prey.</p
Biomass Index (kg<sup>-1</sup> Ă km of transect) of a selected set of terrestrial birds and mammals, according to the Human Footprint Index, and associated correlation curves.
<p>The four study sites for jaguar density assessment are given on the index scale, according to their mean value. The two pictures show sites with a 5â10 Index value (left) and a 15â20 Index value (right).</p
Results of four camera-trapping surveys in French Guiana for jaguars.
<p>Results of four camera-trapping surveys in French Guiana for jaguars.</p
La PlanÚte Revisitée en Corse 2019-2021 : un grand inventaire de la biodiversité négligée dans une ßle méditerranéenne
International audienceFrom 2019 to 2021, scientific field campaigns have been organised in Corsica by the MusĂ©um national dâHistoire naturelle, the Office français de la biodiversitĂ© and the CollectivitĂ© de Corse as part of the âOur Planet Reviewedâ naturalist exploration programme. This paper presents the context, the state of biogeographical and taxonomic knowledge prior to our expeditions, and the objectives, the methods and the first results obtained. The aim was to establish a modern survey of the species present in a selection of sites representative of different Corsican ecosystems, and to further develop the natural history collections through depositing new specimens and species with associated standard DNA barcodes, useful for their identification. Over a period of three years, nineteen sites were surveyed with a semi-standardised protocol and a large-scale trapping scheme was organised in three of these. Sampling efforts focused on forest habitats at higher altitudes and on coastal dune and lowland marshland habitats. A vast array of methods was used to collect invertebrates, with a specific effort on flightinterception traps and pan traps. A total of 34 experts participated to the field surveys and more than 80 further contributed to the study of the specimens. Occurrence data are available in the Inventaire national du patrimoine naturel (http://www.inpn.fr) and, for specimens processed through DNA barcoding, specimen and DNA sequencing data will be accessible in the Barcode of Life datasystems (BOLD : http://www.boldsystems.org). In early 2023, the assembled datasets included 31,100 occurrence data for 3,900 taxa of terrestrial arthropods, representing a 53% increase in publicly available data for the island. More than 6,800 DNA barcode sequences have been produced for arthropods, representing a 14-fold increase in available sequences of Corsican insects compared to those available before the start of the programme. So far, these efforts resulted in producing the first Corsican records for 148 species and in the description of 12 species new to science.De 2019 Ă 2021, des missions scientifiques de terrain ont Ă©tĂ© organisĂ©es en Corse par le MusĂ©um national dâHistoire naturelle, lâOffice français de la biodiversitĂ© et la CollectivitĂ© de Corse dans le cadre du programme dâexploration naturaliste âLa PlanĂšte RevisitĂ©eâ. Cet article prĂ©sente le contexte, lâĂ©tat des connaissances biogĂ©ographiques et taxinomiques avant le dĂ©but du programme, les objectifs, les mĂ©thodes ainsi que les premiers rĂ©sultats obtenus. Lâobjectif Ă©tait dâĂ©tablir un inventaire moderne des espĂšces prĂ©sentes dans une sĂ©rie de sites reprĂ©sentatifs de diffĂ©rents Ă©cosystĂšmes et dâenrichir les collections dâhistoire naturelle de nouveaux spĂ©cimens et nouvelles espĂšces, et en y associant des codes-barres ADN standards, utiles Ă leur identification. Pendant les trois ans, 19 sites ont Ă©tĂ© inventoriĂ©s de façon semi-standardisĂ©e dont trois ont bĂ©nĂ©ficiĂ© dâun dispositif de piĂ©geage dâampleur. Lâaccent a Ă©tĂ© mis sur lâĂ©chantillonnage des espĂšces forestiĂšres, ainsi que sur les piĂšges Ă interception et les assiettes colorĂ©es pour les diptĂšres et les hymĂ©noptĂšres. Au total, 34 experts ont participĂ© aux inventaires de terrain et plus de 80 ont contribuĂ© Ă lâĂ©tude du matĂ©riel. Les donnĂ©es dâobservation sont mises Ă disposition dans lâInventaire national du patrimoine naturel (http://www.inpn.fr), et pour les individus associĂ©s Ă des codes-barres ADN, les donnĂ©es des spĂ©cimens et les sĂ©quences ADN seront accessibles dans le Barcode of Life datasystems (BOLD : http://www.boldsystems.org). DĂ©but 2023, les jeux de donnĂ©es produits comprennent 31 100 donnĂ©es dâoccurrence pour 3900 taxons dâarthropodes terrestres, ce qui reprĂ©sente une augmentation de 53 % des donnĂ©es publiques disponibles pour lâĂźle. Les codes-barres ADN de plus de 6800 spĂ©cimens dâarthropodes ont Ă©tĂ© produits, ce qui reprĂ©sente 14 fois plus de sĂ©quences existantes pour les insectes de Corse que ce qui Ă©tait disponible avant le dĂ©but du programme. JusquâĂ prĂ©sent, 148 signalements nouveaux et 12 espĂšces nouvelles pour la Science ont Ă©tĂ© publiĂ©s