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Brain functional and structural changes lead to cognitive decline during aging, but a high level of cognitive stimulation during life can improve cognitive performances in the older adults, forming the cognitive reserve. Noradrenaline has been proposed as a molecular link between environmental stimulation and constitution of the cognitive reserve. Taking advantage of the ability of olfactory stimulation to activate noradrenergic neurons of the locus coeruleus, we used repeated olfactory enrichment sessions over the mouse lifespan to enable the cognitive reserve buildup. Mice submitted to olfactory enrichment, whether started in early or late adulthood, displayed improved olfactory discrimination at late ages and interestingly, improved spatial memory and cognitive flexibility. Moreover, olfactory and non-olfactory cognitive performances correlated with increased noradrenergic innervation in the olfactory bulb and dorsal hippocampus. Finally, c-Fos mapping and connectivity analysis revealed task-specific remodeling of functional neural networks in enriched older mice. Long-term olfactory enrichment thus triggers structural noradrenergic plasticity and network remodeling associated with better cognitive aging and thereby forms a promising mouse model of the cognitive reserve buildup., Competing Interests: Declaration of Competing Interest The authors declare no conflict of interest., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Normal brain aging is associated with deficits in cognitive and sensory processes, due to subtle impairment of synaptic contacts and plasticity. Impairment may be discrete in basal conditions but is revealed when cerebral plasticity is involved, such as in learning contexts. We used olfactory perceptual learning, a non-associative form of learning in which discrimination between perceptually similar odorants is improved following exposure to these odorants, to better understand the cellular bases of olfactory aging in mice. We first evaluated learning ability and memory retention in 2-, 6-, 12-, and 18-month-old mice, and identified 12 months as a pivotal age when memory retention subtly declines before learning becomes totally impaired at later ages. We then showed that learning-induced structural plasticity of adult-born granule cells is specific to cells responding to the learned odorants in the olfactory bulb of young adult mice and loses its specificity in 12-month-old mice, in parallel to memory impairment. Taken together, our data refine our understanding of aging-related impairment of plasticity mechanisms in the olfactory bulb and consequent induction of olfactory learning and memory deficits., (Copyright © 2022. Published by Elsevier Inc.)

Purpose: Aortic stiffness is a functional and structural consequence of ageing and arteriosclerosis. Regional arterial stiffness can be easily evaluated using pOpmetre(®) (Axelife SAS, France). This new technique assesses the pulse wave transit time (TT) between the finger (TTf) and the toe (TTt). Based on height chart, regional pulse wave velocity (PWV) between the toe and the finger can be estimated (PWVtf). pOpscore(®) index is also calculated as the ratio between PWVtoe and PWVfinger and can be considered as a peripheral vascular stiffness index. The aim of the study was to evaluate the relationship between pOpmetre(®) indices and the presence of carotid plaques in a population with cardiovascular risk factors., Methods: In 77 consecutive patients recruited for a vascular screening for atherosclerosis (46 men aged 54 ± 2 years; 31 women aged 49 ± 3 years; ns), the difference between TTt and TTf (called Dt-f), the regional pulse wave velocity between the toe and the finger (PWVtf = constant × height/Dt-fm/s) and pOpscore(®) were measured by pOpmetre(®). Presence of carotid plaques was assessed using ultrasound imaging. The local aortic stiffness (AoStiff) was evaluated by the Physioflow(®) system., Results: No difference was found between patients with or without carotid plaques (n=25 versus 52) for Ankle-Brachial Pressure Index (ABPI: 1.15 ± 0.04 versus 1.12 ± 0.03), nor for diastolic or systolic blood pressure (87 ± 3 versus 82 ± 2; 137 ± 3 versus 132 ± 2 mmHg). The first group was older than the second (59 ± 2 versus 49 ± 2 years, P<0.002) with a larger intimae media thickness (0.69 ± 0.02 versus 0.63 ± 0.01 mm, P<0.004), a higher AoStiff (10.4 ± 0.7 versus 8.2 ± 0.5m/s, P<0.02), and PWVtf (14.3 ± 1.0 versus 10.7 ± 0.7 m/s, P<0.004) and a shorter Dt-f (57.9 ± 5.1 versus 73.5 ± 3.5 ms, P<0.01). PWVtf (r(2)=0.49, P<0.0001) and Dt-f (r(2)=0.54, P<0.0001) correlated with age. A significant difference in pOpscore(®) index was observed between both groups (1.51 ± 0.3 versus 1.41 ± 0.2, P<0.006)., Conclusion: Our results show a significant arterial stiffness indices measured by pOpmetre(®) in patients with and without carotid plaques., (Copyright © 2013 Elsevier Masson SAS. All rights reserved.)

Unlabelled: Various statistic predictive models have been developed to predict the status of the non-sentinel lymph nodes (NSLN) when the sentinel one was invaded by tumor cells in the case of breast invasive carcinoma. The objective of this study was to compare the accuracy of three of these statistic models: the MSKCC nomogram, the Tenon score and the MDA score. The study was conducted at Croix Rousse Hospital, Lyon, France., Objective: When sentinel lymph node is invaded by metastasis, complete lymph node dissection of the axilla can be avoided using statistic predictive models especially when talking about micrometastases and moreover about isolated tumor cells in the sentinel lymph node. Over the different existing models, we tested the three most used ones to determine the model that is most adapted to our everyday practice., Method: The study population consisted of 77 women with an invasive breast cancer treated by complete axillary lymph node dissection for metastatic sentinel lymph node. Over the nine models already published, we focused on three of them due to their ease to use as well as their good preliminary results: the Memorial Sloan-Kettering Cancer Center nomogram (MSKCC), the Tenon score and the M.D Anderson score (MDA). Different criteria are used by these models, but all of them take in consideration: tumor size, multifocality, tumor type, lymphovascular invasion, hormonal receptors, number of sentinel lymph node resected, degree of sentinel lymph node invasion (i.e. macrometastasis, micrometastasis or isolated tumor cells) and histologic method used to diagnose sentinel lymph node invasion. These scores are validated depending on their false negative ratio as well as the proportion of patient selected as having a low risk of non-sentinel lymph node invasion. The major criterion for the MSKCC score is the calibration that compares the predicted likelihood of invasion and the histologically proved one., Results: The rate of non-sentinel lymph node invasion was 37.6%. The discrimination of the three models was good with an AUC of 0.74 for both MSKCC nomogram and Tenon score and of 0.72% for MDA score. MSKCC nomogram was well calibrated (P=0.23). The false negative ratio was 0 (CI 95%: 0-18.1%) for MSKCC nomogram, 16.7% (CI 95%: 8.6%-27.8%) for Tenon score and 16% (CI 95%: 6.8-31%) for MDA score. The percentage of patients considered as having a low risk of invasion of the non-sentinel lymph node was 20.5% for MSKCC nomogram, 34.7% for MDA score and 47.4% for Tenon score., Conclusion: MSKCC nomogram seems to be the statistic model that is most adapted to the population we studied. To validate the Tenon and MDA score, we should have a most important population., (Copyright © 2012 Elsevier Masson SAS. All rights reserved.)