18 research outputs found
Olfactory Enrichment Influences Adult Neurogenesis Modulating GAD67 and Plasticity-Related Molecules Expression in Newborn Cells of the Olfactory Bulb
The olfactory bulb (OB) is a highly plastic region of the adult mammalian brain characterized by continuous integration of inhibitory interneurons of the granule (GC) and periglomerular cell (PGC) types. Adult-generated OB interneurons are selected to survive in an experience-dependent way but the mechanisms that mediate the effects of experience on OB neurogenesis are unknown. Here we focus on the new-generated PGC population which is composed by multiple subtypes. Using paradigms of olfactory enrichment and/or deprivation combined to BrdU injections and quantitative confocal immunohistochemical analyses, we studied the effects of olfactory experience on adult-generated PGCs at different survival time and compared PGC to GC modulation. We show that olfactory enrichment similarly influences PGCs and GCs, increasing survival of newborn cells and transiently modulating GAD67 and plasticity-related molecules expression. However, PGC maturation appears to be delayed compared to GCs, reflecting a different temporal dynamic of adult generated olfactory interneuron integration. Moreover, olfactory enrichment or deprivation do not selectively modulate the survival of specific PGC phenotypes, supporting the idea that the integration rate of distinct PGC subtypes is independent from olfactory experience
Palaeogenomics of Upper Palaeolithic to Neolithic European hunter-gatherers
Modern humans have populated Europe for more than 45,000 years1,2. Our knowledge of the genetic relatedness and structure of ancient hunter-gatherers is however limited, owing to the scarceness and poor molecular preservation of human remains from that period3. Here we analyse 356 ancient hunter-gatherer genomes, including new genomic data for 116 individuals from 14 countries in western and central Eurasia, spanning between 35,000 and 5,000 years ago. We identify a genetic ancestry profile in individuals associated with Upper Palaeolithic Gravettian assemblages from western Europe that is distinct from contemporaneous groups related to this archaeological culture in central and southern Europe4, but resembles that of preceding individuals associated with the Aurignacian culture. This ancestry profile survived during the Last Glacial Maximum (25,000 to 19,000 years ago) in human populations from southwestern Europe associated with the Solutrean culture, and with the following Magdalenian culture that re-expanded northeastward after the Last Glacial Maximum. Conversely, we reveal a genetic turnover in southern Europe suggesting a local replacement of human groups around the time of the Last Glacial Maximum, accompanied by a north-to-south dispersal of populations associated with the Epigravettian culture. From at least 14,000 years ago, an ancestry related to this culture spread from the south across the rest of Europe, largely replacing the Magdalenian-associated gene pool. After a period of limited admixture that spanned the beginning of the Mesolithic, we find genetic interactions between western and eastern European hunter-gatherers, who were also characterized by marked differences in phenotypically relevant variants
Risk factors for infections caused by carbapenem-resistant Enterobacterales: an international matched case-control-control study (EURECA)
Cases were patients with complicated urinary tract infection (cUTI), complicated intraabdominal (cIAI), pneumonia or bacteraemia from other sources (BSI-OS) due to CRE; control groups were patients with infection caused by carbapenem-susceptible Enterobacterales (CSE), and by non-infected patients, respectively. Matching criteria included type of infection for CSE group, ward and duration of hospital admission. Conditional logistic regression was used to identify risk factors. Findings Overall, 235 CRE case patients, 235 CSE controls and 705 non-infected controls were included. The CRE infections were cUTI (133, 56.7%), pneumonia (44, 18.7%), cIAI and BSI-OS (29, 12.3% each). Carbapenemase genes were found in 228 isolates: OXA-48/like, 112 (47.6%), KPC, 84 (35.7%), and metallo-beta-lactamases, 44 (18.7%); 13 produced two. The risk factors for CRE infection in both type of controls were (adjusted OR for CSE controls; 95% CI; p value) previous colonisation/infection by CRE (6.94; 2.74-15.53; <0.001), urinary catheter (1.78; 1.03-3.07; 0.038) and exposure to broad spectrum antibiotics, as categorical (2.20; 1.25-3.88; 0.006) and time-dependent (1.04 per day; 1.00-1.07; 0.014); chronic renal failure (2.81; 1.40-5.64; 0.004) and admission from home (0.44; 0.23-0.85; 0.014) were significant only for CSE controls. Subgroup analyses provided similar results. Interpretation The main risk factors for CRE infections in hospitals with high incidence included previous coloni-zation, urinary catheter and exposure to broad spectrum antibiotics
Palaeogenomics of Upper Palaeolithic to Neolithic European hunter-gatherers
Modern humans have populated Europe for more than 45,000 years(1,2). Our knowledge of the genetic relatedness and structure of ancient hunter-gatherers is however limited, owing to the scarceness and poor molecular preservation of human remains from that period(3). Here we analyse 356 ancient hunter-gatherer genomes, including new genomic data for 116 individuals from 14 countries in western and central Eurasia, spanning between 35,000 and 5,000 years ago. We identify a genetic ancestry profile in individuals associated with Upper Palaeolithic Gravettian assemblages from western Europe that is distinct from contemporaneous groups related to this archaeological culture in central and southern Europe(4), but resembles that of preceding individuals associated with the Aurignacian culture. This ancestry profile survived during the Last Glacial Maximum (25,000 to 19,000 years ago) in human populations from southwestern Europe associated with the Solutrean culture, and with the following Magdalenian culture that re-expanded northeastward after the Last Glacial Maximum. Conversely, we reveal a genetic turnover in southern Europe suggesting a local replacement of human groups around the time of the Last Glacial Maximum, accompanied by a north-to-south dispersal of populations associated with the Epigravettian culture. From at least 14,000 years ago, an ancestry related to this culture spread from the south across the rest of Europe, largely replacing the Magdalenian-associated gene pool. After a period of limited admixture that spanned the beginning of the Mesolithic, we find genetic interactions between western and eastern European hunter-gatherers, who were also characterized by marked differences in phenotypically relevant variants.Molecular Technology and Informatics for Personalised Medicine and Healt
Effect of appropriate combination therapy on mortality of patients with bloodstream infections due to carbapenemase-producing Enterobacteriaceae (INCREMENT): a retrospective cohort study
Background The best available treatment against carbapenemase-producing Enterobacteriaceae (CPE) is unknown. The objective of this study was to investigate the effect of appropriate therapy and of appropriate combination therapy on mortality of patients with bloodstream infections (BSIs) due to CPE. Methods In this retrospective cohort study, we included patients with clinically significant monomicrobial BSIs due to CPE from the INCREMENT cohort, recruited from 26 tertiary hospitals in ten countries. Exclusion criteria were missing key data, death sooner than 24 h after the index date, therapy with an active antibiotic for at least 2 days when blood cultures were taken, and subsequent episodes in the same patient. We compared 30 day all-cause mortality between patients receiving appropriate (including an active drug against the blood isolate and started in the first 5 days after infection) or inappropriate therapy, and for patients receiving appropriate therapy, between those receiving active monotherapy (only one active drug) or combination therapy (more than one). We used a propensity score for receiving combination therapy and a validated mortality score (INCREMENT-CPE mortality score) to control for confounders in Cox regression analyses. We stratified analyses of combination therapy according to INCREMENT-CPE mortality score (0\u20137 [low mortality score] vs 8\u201315 [high mortality score]). INCREMENT is registered with ClinicalTrials.gov, number NCT01764490. Findings Between Jan 1, 2004, and Dec 31, 2013, 480 patients with BSIs due to CPE were enrolled in the INCREMENT cohort, of whom we included 437 (91%) in this study. 343 (78%) patients received appropriate therapy compared with 94 (22%) who received inappropriate therapy. The most frequent organism was Klebsiella pneumoniae (375 [86%] of 437; 291 [85%] of 343 patients receiving appropriate therapy vs 84 [89%] of 94 receiving inappropriate therapy) and the most frequent carbapenemase was K pneumoniae carbapenemase (329 [75%]; 253 [74%] vs 76 [81%]). Appropriate therapy was associated with lower mortality than was inappropriate therapy (132 [38\ub75%] of 343 patients died vs 57 [60\ub76%] of 94; absolute difference 22\ub71% [95% CI 11\ub70\u201333\ub73]; adjusted hazard ratio [HR] 0\ub745 [95% CI 0\ub733\u20130\ub762]; p<0\ub70001). Among those receiving appropriate therapy, 135 (39%) received combination therapy and 208 (61%) received monotherapy. Overall mortality was not different between those receiving combination therapy or monotherapy (47 [35%] of 135 vs 85 [41%] of 208; adjusted HR 1\ub763 [95% CI 0\ub767\u20133\ub791]; p=0\ub728). However, combination therapy was associated with lower mortality than was monotherapy in the high-mortality-score stratum (30 [48%] of 63 vs 64 [62%] of 103; adjusted HR 0\ub756 [0\ub734\u20130\ub791]; p=0\ub702), but not in the low-mortality-score stratum (17 [24%] of 72 vs 21 [20%] of 105; adjusted odds ratio 1\ub721 [0\ub756\u20132\ub756]; p=0\ub762). Interpretation Appropriate therapy was associated with a protective effect on mortality among patients with BSIs due to CPE. Combination therapy was associated with improved survival only in patients with a high mortality score. Patients with BSIs due to CPE should receive active therapy as soon as they are diagnosed, and monotherapy should be considered for those in the low-mortality-score stratum. Funding Spanish Network for Research in Infectious Diseases, European Development Regional Fund, Instituto de Salud Carlos III, and Innovative Medicines Initiative
Mechanisms and aging related diseases
Le vieillissement est une perte progressive et inéluctable des capacités fonctionnelles de l’organisme. Des caractéristiques socio-économiques, des facteurs génétiques et le genre influent sur ce processus et en déterminent la complexité. Les mécanismes moléculaires et cellulaires, qui fondent la physiologie du vieillissement et de la longévité, commencent à être mieux élucidés. Souvent ambivalents, ils sont aussi impliqués dans la survenue de nombreuses pathologies liées à l’âge. Certains d’entre-eux (les principaux) sont décrits dans cet article (restriction calorique, séquences télomériques, klotho, Apolipoprotéine E, voie de signalisation mTOR, axe IGF-1/PI3 kinase/insuline, sirtuines, autophagie, radicaux libres, etc.). Une meilleure compréhension de ces mécanismes suscite beaucoup d’espoirs en termes de prévention et de perspectives thérapeutiques. Néanmoins, des dérives éthiques possibles sont redoutées. Le vieillissement est, ainsi, un enjeu sociétal et de santé publique aussi bien dans les pays développés que dans les pays en développement. Le problème de sa prise en charge se posera avec acuité devant l’augmentation de l’espérance de vie et du nombre de personnes âgées dans le monde.Aging is known as a process leading to a progressive and relentless decline of functional capacities. Social, economic, gender and genetic factors are key modulators of its complexity. A better understanding of cellular and molecular mechanisms that underlie aging and life span physiology is slowly but surely occurring. Here, we give a comprehensive synthesis of the main biological mechanisms controlling aging and aging related diseases (caloric restriction, telomeric sequences, Klotho, Apolipoproteine E, mTOR pathway, IGF-1/PI3 kinase/insulin axis, sirtuins, autophagy, free radicals...). Promising hopes in terms of aging prevention and therapeutic perspectives are made in the near future. Nevertheless, general public fear ethical excesses. At all events, aging is becoming a social and public health stake in developed and developing countries. The elderly care management will be a huge issue regarding the enhancement of life span and the growing number of seniors worldwide
External validation of the INCREMENT-CPE mortality score in a carbapenem-resistant Klebsiella pneumoniae bacteraemia cohort: the prognostic significance of colistin resistance
External validation of the INCREMENT-CPE risk score (ICS) for 30-day
all-cause mortality is needed. There is also scarce information about
whether colistin resistance influences the prognosis of
carbapenem-resistant Klebsiella pneumoniae (CRKp) bacteraemia. In this
study, the ability of ICS to predict all-cause mortality in the KAPECOR
cohort was calculated using the area under the receiver operating
characteristic (AUROC) curve. The association of colistin resistance
with mortality was studied. The ICS showed an AUROC curve of 0.77 (95%
CI 0.68-0.86). A cut-off of 8 points showed 96.8% sensitivity and
50.7% specificity. Mortality of low-risk patients was not different in
those treated with monotherapy versus combination therapy. However,
mortality of high-risk patients treated with combination therapy
(37.8%) was significantly lower than in those treated with monotherapy
(68.4%) (P = 0.008). To study the prognostic significance of colistin
resistance, 83 selected cases of bacteraemia due to colistin-susceptible
CRKp were obtained from the INCREMENT cohort for comparison. Colistin
resistance could not be shown to be associated with higher mortality in
either the high-risk ICS group [adjusted odds ratio (aOR) = 1.56, 95%
CI 0.69-3.33; P = 0.29] or in 37 ICS-matched pairs (aOR = 1.38, 95% CI
0.55-3.42; P = 0.49), or in a sensitivity analysis including only KPC
isolates (aOR = 1.81, 95% CI 0.73-4.57; P = 0.20), but the precision of
estimates was low. These results validate ICS for all-cause mortality
and to optimise targeted therapy for CRKp bacteraemia. Colistin
resistance was not clearly associated with increased mortality. (C) 2019
Elsevier B.V. and International Society of Chemotherapy. All rights
reserved