110 research outputs found

    The neuropsychology and neuroanatomy of reduplicative paramnesia.

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    Reduplicative paramnesia refers to the delusional belief that there are identical places in different locations. In this case-control study we investigated the clinical, phenomenological, neuropsychological and neuroanatomical data of eleven patients with reduplicative paramnesia and compared them against a control group of eleven patients with severe spatial disorientation without signs of reduplicative paramnesia. We show that most patients with reduplicative paramnesia report that a current place is reduplicated and/or relocated to an other familiar place. Patients with reduplicative paramnesia show a higher prevalence of deficits in the executive functions compared to the control patients, while mnestic and visuo-spatial deficits were both frequent in patients with reduplicative paramnesia and the control group. Patients with reduplicative paramnesia mostly suffer from right hemispheric lesions with a maximal overlap in the dorsolateral prefrontal cortex. Using lesion network mapping we show that lesions causing reduplicative paramnesia are connected to bilateral anterior insula and the right cingulate cortex. We argue that patients with reduplicative paramnesia fail to integrate the actual context with visuo-spatial memories and personal relevant emotional information due to a disruption of the neural network within the anterior temporal lobe, the cingulate cortex and the anterior insula. Also patients with reduplicative paramnesia are not able to resolve this conflict due to the lesion of the dorsolateral prefrontal cortex and executive dysfunction

    Fronto-Temporal Disconnection Within the Presence Hallucination Network in Psychotic Patients With Passivity Experiences.

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    Psychosis, characterized by hallucinations and delusions, is a common feature of psychiatric disease, especially schizophrenia. One prominent theory posits that psychosis is driven by abnormal sensorimotor predictions leading to the misattribution of self-related events. This misattribution has been linked to passivity experiences (PE), such as loss of agency and, more recently, to presence hallucinations (PH), defined as the conscious experience of the presence of an alien agent while no person is actually present. PH has been observed in schizophrenia, Parkinson's disease, and neurological patients with brain lesions and, recently, the brain mechanisms of PH (PH-network) have been determined comprising bilateral posterior middle temporal gyrus (pMTG), inferior frontal gyrus (IFG), and ventral premotor cortex (vPMC). Given that the experience of an alien agent is a common feature of PE, we here analyzed the functional connectivity within the PH-network in psychotic patients with (N = 39) vs without PE (N = 26). We observed reduced fronto-temporal functional connectivity in patients with PE compared to patients without PE between the right pMTG and the right and left IFG of the PH-network. Moreover, when seeding from these altered regions, we observed specific alterations with brain regions commonly linked to auditory-verbal hallucinations (such as Heschl's gyrus). The present connectivity findings within the PH-network extend the disconnection hypothesis for hallucinations to the specific case of PH and associates the PH-network with key brain regions for frequent psychotic symptoms such as auditory-verbal hallucinations, showing that PH are relevant to the study of the brain mechanisms of psychosis and PE

    Dental calculus and isotopes provide direct evidence of fish and plant consumption in Mesolithic Mediterranean

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    In this contribution we dismantle the perceived role of marine resources and plant foods in the subsistence economy of Holocene foragers of the Central Mediterranean using a combination of dental calculus and stable isotope analyses. The discovery of fish scales and flesh fragments, starch granules and other plant and animal micro-debris in the dental calculus of a Mesolithic forager dated to the end of the 8th millenium BC and buried in the Vlakno Cave on Dugi Otok Island in the Croatian Archipelago demonstrates that marine resources were regularly consumed by the individual together with a variety of plant foods. Since previous stable isotope data in the Eastern Adriatic and the Mediterranean region emphasises that terrestrial-based resources contributed mainly to Mesolithic diets in the Mediterranean Basin, our results provide an alternative view of the dietary habits of Mesolithic foragers in the Mediterranean region based on a combination of novel methodologies and data

    Photocatalytic Nanolithography of Self-Assembled Monolayers and Proteins

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    Self-assembled monolayers of alkylthiolates on gold and alkylsilanes on silicon dioxide have been patterned photocatalytically on sub-100 nm length-scales using both apertured near-field and apertureless methods. Apertured lithography was carried out by means of an argon ion laser (364 nm) coupled to cantilever-type near-field probes with a thin film of titania deposited over the aperture. Apertureless lithography was carried out with a helium–cadmium laser (325 nm) to excite titanium-coated, contact-mode atomic force microscope (AFM) probes. This latter approach is readily implementable on any commercial AFM system. Photodegradation occurred in both cases through the localized photocatalytic degradation of the monolayer. For alkanethiols, degradation of one thiol exposed the bare substrate, enabling refunctionalization of the bare gold by a second, contrasting thiol. For alkylsilanes, degradation of the adsorbate molecule provided a facile means for protein patterning. Lines were written in a protein-resistant film formed by the adsorption of oligo(ethylene glycol)-functionalized trichlorosilanes on glass, leading to the formation of sub-100 nm adhesive, aldehyde-functionalized regions. These were derivatized with aminobutylnitrilotriacetic acid, and complexed with Ni2+, enabling the binding of histidine-labeled green fluorescent protein, which yielded bright fluorescence from 70-nm-wide lines that could be imaged clearly in a confocal microscope

    GWAS for quantitative resistance phenotypes in Mycobacterium tuberculosis reveals resistance genes and regulatory regions

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    YesDrug resistance diagnostics that rely on the detection of resistance-related mutations could expedite patient care and TB eradication. We perform minimum inhibitory concentration testing for 12 anti-TB drugs together with Illumina whole-genome sequencing on 1452 clinical Mycobacterium tuberculosis (MTB) isolates. We evaluate genome-wide associations between mutations in MTB genes or non-coding regions and resistance, followed by validation in an independent data set of 792 patient isolates. We confirm associations at 13 non-canonical loci, with two involving non-coding regions. Promoter mutations are measured to have smaller average effects on resistance than gene body mutations. We estimate the heritability of the resistance phenotype to 11 anti-TB drugs and identify a lower than expected contribution from known resistance genes. This study highlights the complexity of the genomic mechanisms associated with the MTB resistance phenotype, including the relatively large number of potentially causal loci, and emphasizes the contribution of the non-coding portion of the genome.Biomedical research grant from the American Lung Association (PI MF, RG-270912-N), a K01 award from the BD2K initiative (PI MF, ES026835), and an NIAID U19 CETR grant (P.I. M.M., AI109755), the Belgian Science Policy (Belspo) (L.R., C.J.M.)

    Comportements alimentaires durant l'Antiquité tardive en Gaule du Nord : l'exemple des sujets de la nécropole de l'Ilot de la Boucherie (IIIe-IVe siècles ap. J.-C., Amiens)

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    International audienceDuring Late Antiquity, Northern Gaul played an important role in the relations between the Roman Empire and the barbarian world. In order to better understand the lifestyles of these populations, and in particular their dietary practices, a broad isotope analysis (δ13C and δ15N) was undertaken on subjects from the Ilot de la Boucherie site in Amiens.We will present here the first results of this research concerning thirty-three subjects from this site as well as thirty-two subjects from three contemporary neighbouring sites and a corpus of twenty-eight specimens of domestic species.Comparison of the isotope values of human subjects with those of animals from the associated sites has revealed first of all a significant enrichment in 13C which could be the first documented isotopic evidence of millet consumption in ancient Europe. Secondly, the values obtained from δ15N are relatively low and suggest a regular consumption of legumes. Based on statistical studies, the sampled subjects seem to form a homogeneous group with regard to eating habits. The intra-individual study also determined that the majority of the subjects at the Ilot de la Boucherie site had the same diet during childhood and in adulthood. On the scale of the Roman Empire, this research has highlighted the singularity of the diet of the Northern Gauls, as the isotopic relationships between humans and the associated fauna are not found in any published site dating from this period. These results are an advance in the knowledge of the dietary habits of the inhabitants of Northern Gaul, which seem to differ from other late Antique populations already studied using isotope markers.Translated with www.DeepL.com/Translator (free version)Durant la période de l'Antiquité Tardive, la Gaule du Nord joue un rôle important dans les relations entre l'Empire romain et le monde barbare. Afin de mieux comprendre les modes de vie de ces populations, et notamment leurs pratiques alimentaires, une large analyse isotopique (δ13C et δ15N) a été entreprise sur des sujets provenant du site de l'Ilot de la Boucherie, à Amiens.Nous présenterons ici les premiers résultats de cette recherche concernant trente-trois sujets de ce site ainsi que trente-deux sujets issus de trois sites voisins contemporains et un corpus de faune de vingt-huit spécimens d'espèces domestiques.La comparaison des valeurs isotopiques des sujets humains avec celles des animaux des sites associés a permis de mettre en évidence tout d'abord un enrichissement important en 13C qui pourrait être la première preuve documentée isotopiquement de consommation de millet pour la période antique en Europe. Ensuite les valeurs obtenues de δ15N sont relativement basses et laissent supposer une consommation régulière de légumineuses. D'après les études statistiques, les sujets échantillonnés semblent formés un groupe homogène en ce qui concerne les habitudes alimentaires. L'étude intra-individuelle a permis également de déterminer que la majorité des sujets du site de l'Ilot de la Boucherie possède le même régime alimentaire pendant l'enfance et à l'âge adulte. A l'échelle de l'Empire romain, cette recherche a permis de mettre en évidence la singularité du régime alimentaire des gaulois du Nord, les relations isotopiques entre les humains et la faune associée ne se retrouvant dans aucun site publié daté de cette période. Ces résultats sont une avancée dans la connaissance des habitudes alimentaires des habitants de Gaule du Nord qui semblent se démarquer des autres populations tardo-antiques déjà étudiées à partir des marqueurs isotopiques
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