Cognitive reserve and cognitive performance of patients with focal frontal lesions

The Cognitive reserve (CR) hypothesis was put forward to account for the variability in cognitive performance of patients with similar degrees of brain pathology. Compensatory neural activity within the frontal lobes has often been associated with CR. For the first time we investigated the independent effects of two CR proxies, education and NART IQ, on measures of executive function, fluid intelligence, speed of information processing, verbal short term memory (vSTM), naming, and perception in a sample of 86 patients with focal, unilateral frontal lesions and 142 healthy controls. We fitted multiple linear regression models for each of the cognitive measures and found that only NART IQ predicted executive and naming performance. Neither education nor NART IQ predicted performance on fluid intelligence, processing speed, vSTM or perceptual abilities. Education and NART IQ did not modify the effect of lesion severity on cognitive impairment. We also found that age significantly predicted performance on executive tests and the majority of our other cognitive measures, except vSTM and GNT. Age was the only predictor for fluid intelligence. This latter finding suggests that age plays a role in executive performance over and above the contribution of CR proxies in patients with focal frontal lesions. Overall, our results suggest that the CR proxies do not appear to modify the relationship between cognitive impairment and frontal lesions

Intra- and inter-individual variability of executive functions:Determinant and modulating factors in healthy and pathological conditions

open4siExecutive functioning generally refers to the ability to organize thought and action based on intentions and goals, especially in novel, complex or difficult situations. Executive functioning is a multifaceted psychological construct that may be depicted as a set of related but separable high-level cognitive abilities, possibly supported by the prefrontal cortex and implemented by larger brain networks (Miyake et al., 2000; Shallice and Burgess, 1996 but see Duncan et al., 1997). Many models exist that emphasize commonalities or differences among various executive functions (EF). While the number and type of EF that exist remain a topic of debate, most authors would agree that EF show high intra- and inter-individual variability in terms of their cognitive and behavioral manifestations. But what are the determinant and modulating factors that might explain the variability across EF? Do neuro-anatomical or neuro-functional factors and/or the environment influence EF? The overall goal of our research topic was to provide a forum to explore the contributions of different research groups investigating intra- and inter-individual variability in EF. We welcomed empirical, theoretical and meta-analytical work involving both clinical and healthy human populations. We were impressed by the number of authors who did indeed rally to our call; our research topic resulted in contributions from 187 authors and 39 published articles. At the time of writing, our research topic has resulted in an impressive 62,809 total views and 5,728 article downloads. We hope after reading these articles, you will be more sensitive to the various factors that contribute to intra- and inter-subject variability in EF and will be inspired to consider these when studying EF in both healthy and pathological conditions. What follows is a brief overview of the contributions to our research topic. We aim to highlight some of the key influences on EF variability, and some of the interesting questions to emerge from these articles that we hope will encourage and influence future research. We appreciate that this editorial cannot fully do our research topic justice in terms of the breadth and depth of topics/questions included and so we encourage you to read further the contributions that these articles offer to the research area of EF.openSarah E. MacPherson, Celine R. Gillebert, Gail A. Robinson, Antonino VallesiMacpherson, Sarah E.; Gillebert, Celine R.; Robinson, Gail A.; Vallesi, Antonin

Lecture actentielle dans Trop c'est trop de Protais Asseng

Bakony goes in search of a thirteenth child. This child's birth conferred him the "National Dad" title. But the is not the opinion of his multiparous wife Bissabey and it is finally he that is going to feel the case, his belly will take the 13rd child. Bakony symbolizes the research of happiness on a human's back. It is the woman's exploitation by the man. This instrumentalization is then the bone of contention between the couple and their respective adjuvants. Of the woman's side enter in game physician, sorcerer etc. The correct understanding of the story requires various then a dynamic literary analysis. The actantiel analysis seemed most favorable to us (as taught by A. Greimas (1966). Thanks to such a procedure one succeeds in discovering the unsaid of the text. This positions actantiel permitted to know more on the enrollment of such or such actant in such or such actantiel case. Bissabey appeared in forgery to her husband's demand. For Bissabey, the ideal it is to free the woman of the ascendancy of the men, to procure her her full rights, brief the disinstrumentalization. Keywords: Protais Assenge, literay analysis, actantiel analysis Résumé Bakony va à la recherche d'un treizième enfant. La naissance de cet enfant lui conférait le titre de "Papa national" Bakony symbolise la recherche de bonheur sur le dos d'un humain. C'est de l'exploitation de la femme par l'homme. Mais la multipare Bissabey, son épouse, n'est pas de son avis. Cette instrumentalisation est alors la pomme de discorde entre le couple et leurs adjuvants respectifs. Du côté de la femme entrent en jeu médecin, féticheur etc. et c'est finalement Bakonyi lui-même qui va en subir les conséquences: de son ventre sortira le 13e enfant. La compréhension de cette histoire exige alors divers dynamiques d'analyse littéraire. L'analyse actantielle nous a semblé le plus favorable (initiée par A. Greimas (1966). Grâce à une telle procédure on parvient à découvrir le non-dit du texte. Ces positions actantielles ont permis d'en savoir plus sur l'inscription de tel ou de tel actant dans telle ou telle cas actantielle. Bissabey s'est inscrite en faux à la demande de son mari. Pour Bissabey, l'idéal c'est de libérer la femme de l'emprise des hommes, lui procurer ses pleins droits, bref la désinstrumentaliser. Mots-clés : analyse littéraire, analyse actantielle, Protais Asseng (Annales Æquatoria, 22(2001): 137-152

Causes and consequences of structural adjustment programs in the Democratic Republic of Congo (DRC)

Notre recherche a consisté a nous faire une opinion raisonnée sur les interventions des Institutions de Bretton-Woods en République Démocratique de Congo, en nous appuyant sur une analyse de long terme de l’endettement extérieur du pays, et par conséquent à la mise en œuvre des programmes des stabilisations dans les années 70 et d’ajustement structurel depuis les années 80. Cette analyse nous a permis de mettre en lumière les contraintes économiques et sociales, internes et extérieures, auxquelles le pays a dû faire face. Loin de soulager cette économie rentière, les thérapies de choc préconisées par ces Institutions ont provoqué des coûts ou effets secondaires négatifs, délibérément cherché ou non sur d’autres variables (revenu global, niveau des prix, inflation/hyperinflation…). D’autre part, elles ont eu un coût social élevé, et ont contribuées lourdement à une détérioration de la répartition des revenus entre les diverses couches sociales du pays. L’échec des programmes d’ajustement structurel étant aujourd’hui reconnu, il était devenu donc impératif d’imaginer d’autres types d’approches moins superficielles, qui puissent intégrer non-seulement l’équilibre des variables macro et/ou micro-économiques, mais aussi méso-économique ; et donc l’accent doit être désormais mis sur l’amont (discussions des politiques) et sur l’aval (mis au point des projets ou programmes). C’est ainsi que furent mis en place, depuis le milieu des années 90, les mesures d’allègement ou d’annulation de la dette extérieure. L’austérité préconisée aujourd’hui, face à la crise de la dette dans la zone euro, semble ne pas tenir compte des conséquences que les politiques d’inspiration monétariste ont entraînées partout où elles ont été mises en œuvre, et particulièrement en Afrique. Ainsi, nous-nous demandons si le Libéraux ont-ils retenu les leçons des échecs des programmes d’ajustement structurel (PAS) dans les pays ajustés. Pour ce faire, nous-nous sommes permis de proposer quelques perspectives ou voies de sortie afin d’éviter de retomber dans le cycle de la dette que la RD Congo a connut.Our research was to give us a reasoned opinion on the actions of the Bretton-Woods in DR Congo, relying on an analysis of long term external debt of the country, and therefore the implementation of programs stabilization in the 70s and structural adjustment since the 80s. This analysis allowed us to highlight the economic and social constraints, internal and external, that the country faced. Far from alleviating the rentier economy, shock therapies advocated by these institutions have caused costs or negative side effects, deliberately sought or not other variables (total income, inflation/hyperinflation…). On the other hand, they had a high social cost, and contributed heavily to the deterioration of income distribution among different social strata of the country. The failure of structural adjustment programs (SAPs) is regnized today, it has become imperative to imagine other types of less superficial approaches that can integrate not only the balance of macro variables and/or micro-economic, but also meso, and therefore the emphasis should now be placed on the upstream (policy discussion) and downstream (developed projects or programs). Thus were established since the mid 90s, the relief measures or cancellation of the external debt. The austerity advocated today, faced with the debt crisis in the euro area seems to ignore the impact that monetary policies have led to inspiration wherever they have been implemented, particularity in Africa. Thus, we ask whether we Liberals have learned from the failures of adjustment programs (SAPs) in the country originates, the former adjusted. To do this, we have allowed us to propose a few prospects or output channels to avoid failing into the cycle of debt that DR Congo has experienced so far

A Decade of Improvements in Mimiviridae and Marseilleviridae Isolation from Amoeba

International audienceSince the isolation of the first giant virus, the Mimivirus, by T.J. Rowbotham in a cooling tower in Bradford, UK, and after its characterisation by our group in 2003, we have continued to develop novel strategies to isolate additional strains. By first focusing on cooling towers using our original time-consuming procedure, we were able to isolate a new lineage of giant virus called Marseillevirus and a new Mimivirus strain called Mamavirus. In the following years, we have accumulated the world's largest unique collection of giant viruses by improving the use of antibiotic combinations to avoid bacterial contamination of amoeba, developing strategies of preliminary screening of samples by molecular methods, and using a high-throughput isolation method developed by our group. Based on the inoculation of nearly 7,000 samples, our collection currently contains 43 strains of Mimiviridae (14 in lineage A, 6 in lineage B, and 23 in lineage C) and 17 strains of Marseilleviridae isolated from various environments, including 3 of human origin. This study details the procedures used to build this collection and paves the way for the high-throughput isolation of new isolates to improve the record of giant virus distribution in the environment and the determination of their pangenome

Association of plasma biomarkers with cognitive function in persons with dementia and cognitively healthy in the Democratic Republic of Congo

Abstract Introduction This study investigates whether plasma biomarkers (Aβ42/40 and p‐tau 181), APS, as well as apolipoprotein E (APOE) proteotype predict cognitive deficits in elderly adults from the Democratic Republic of Congo. Methods Forty‐four with possible AD (pAD) and 41 healthy control (HC) subjects were screened using CSID and AQ, underwent cognitive assessment with the African Neuropsychology Battery (ANB), and provided blood samples for plasma Aβ42, Aβ40, Aβ42/40, and APOE proteotype. Linear and logistic regression were used to evaluate the associations of plasma biomarkers with ANB tests and the ability of biomarkers to predict cognitive status. Results Patients with pAD had significantly lower plasma Aβ42/40 levels, higher APS, and higher prevalence of APOE E4 allele compared to HC. Groups did not differ in levels of Aβ40, Aβ42, or P‐tau 181. Results showed that Aβ42/40 ratio and APS were significantly associated with African Naming Test (ANT), African List Memory Test (ALMT), and African Visuospatial Memory Test (AVMT) scores, while the presence of APOE E4 allele was associated with ANT, ALMT, AVMT, and APT scores. P‐tau 181 did not show any significant associations while adjusting for age, education, and gender. APS showed the highest area under the curve (AUC) value (AUC = 0.78, 95% confidence interval [CI]: 0.68–0.88) followed by Aβ42/40 (AUC = 0.75, 95% CI: 0.66–0.86) and APOE E4 (AUC = 0.69 (CI 0.57–0.81) in discriminating pAD from HC. Discussion These results demonstrate associations between select plasma biomarker of AD pathology (Aβ42/40), APS, and APOE E4 allele) and ANB test scores and the ability of these biomarkers to differentiate pAD from cognitively normal SSA individuals, consistent with findings reported in other settings