Curing Alzheimer's disease remains hampered by an incomplete understanding of its pathophysiology and progression. Exploring dysfunction in medial temporal lobe networks, particularly the anterior-temporal (AT) and posterior-medial (PM) systems, may provide key insights, as these networks exhibit functional connectivity alterations along the entire Alzheimer's continuum, potentially influencing disease propagation. However, the specific changes in each network and their clinical relevance across stages are not yet fully understood.
View Article and Find Full Text PDFBackground: Subclinical depressive symptoms increase the risk of developing Alzheimer's disease (AD). The neurobiological mechanisms underlying this link may involve stress system dysfunction, notably related to the hippocampus which is particularly sensitive to AD. We aimed to investigate the links between blood stress markers and changes in brain regions involved in the stress response in older adults with or without subclinical depressive symptoms.
View Article and Find Full Text PDFDNA sensing is important for antiviral immunity. The DNA sensor cGAS synthesizes 2'3'-cyclic GMP-AMP (cGAMP), a second messenger that activates STING, which induces innate immunity. cGAMP not only activates STING in the cell where it is produced but cGAMP also transfers to other cells.
View Article and Find Full Text PDFObjective: To provide guidelines to define the place of human factors in the management of critical situations in anaesthesia and critical care.
Design: A committee of nineteen experts from the SFAR and GFHS learned societies was set up. A policy of declaration of links of interest was applied and respected throughout the guideline-producing process.
2'3'-cGAMP is a key molecule in the cGAS-STING pathway. This cyclic dinucleotide is produced by the cytosolic DNA sensor cGAS in response to the presence of aberrant dsDNA in the cytoplasm which is associated with microbial invasion or cellular damage. 2'3'-cGAMP acts as a second messenger and activates STING, the central hub of DNA sensing, to induce type-I interferons and pro-inflammatory cytokines necessary for responses against infection, cancer or cellular stress.
View Article and Find Full Text PDFMedial temporal lobe (MTL) subregions are differentially affected in Alzheimer's disease (AD), with a specific involvement of the entorhinal cortex (ERC), perirhinal cortex and hippocampal cornu ammonis (CA)1. While amyloid (Aβ) and APOEε4 are respectively the first molecular change and the main genetic risk factor in AD, their links with MTL atrophy remain relatively unclear. Our aim was to uncover these effects using baseline data from 130 participants included in the Age-Well study, for whom ultra-high-resolution structural MRI, amyloid-PET and APOEε4 genotype were available.
View Article and Find Full Text PDFIn prolonged pregnancies, the risks of neonatal morbidity and mortality are increased. The aim of this trial was to assess the benefits of maternal information about fetal movement (FM) counting on neonatal outcomes in prolonged pregnancy. It was a prospective, single center, randomized, open-label study conducted from October 2019 to March 2022.
View Article and Find Full Text PDFPattern recognition receptors (PRRs) protect against microbial invasion by detecting specific molecular patterns found in pathogens and initiating an immune response. Although microbial-derived PRR ligands have been extensively characterized, the contribution and relevance of endogenous ligands to PRR activation remains overlooked. Here, we characterize the landscape of endogenous ligands that engage RIG-I-like receptors (RLRs) upon infection by different RNA viruses.
View Article and Find Full Text PDFVaricella-Zoster virus (VZV) causes chickenpox and shingles. Although the infection is associated with severe morbidity in some individuals, molecular mechanisms that determine innate immune responses remain poorly defined. We found that the cGAS/STING DNA sensing pathway was required for type I interferon (IFN) induction during VZV infection and that recognition of VZV by cGAS restricted its replication.
View Article and Find Full Text PDFOlder female drivers could be considered victims of negative stereotypes for two reasons-being a woman and belonging to the older category-but there are no studies specifically in this double context. Two psychosocial questionnaires were created, one assessing the perception of driving abilities in different contexts (PDADC); the second, the perception of the attributes of driving (PAD) with a box for the activation of the stereotype threat. A population of 98 women, aged 65 years or older, comprised the experimental and control groups (quasi-experimental design).
View Article and Find Full Text PDFMedial temporal lobe (MTL) atrophy is a key feature of Alzheimer's disease (AD), however, it also occurs in typical aging. To enhance the clinical utility of this biomarker, we need to better understand the differential effects of age and AD by encompassing the full AD-continuum from cognitively unimpaired (CU) to dementia, including all MTL subregions with up-to-date approaches and using longitudinal designs to assess atrophy more sensitively. Age-related trajectories were estimated using the best-fitted polynomials in 209 CU adults (aged 19-85).
View Article and Find Full Text PDFHuman cells respond to infection by SARS-CoV-2, the virus that causes COVID-19, by producing cytokines including type I and III interferons (IFNs) and proinflammatory factors such as IL6 and TNF. IFNs can limit SARS-CoV-2 replication but cytokine imbalance contributes to severe COVID-19. We studied how cells detect SARS-CoV-2 infection.
View Article and Find Full Text PDFCyclic GMP-AMP (cGAMP) is an immunostimulatory molecule produced by cGAS that activates STING. cGAMP is an adjuvant when administered alongside antigens. cGAMP is also incorporated into enveloped virus particles during budding.
View Article and Find Full Text PDFThe HIV-2 long terminal repeat (LTR) region contains several transcription factor (TF) binding sites. Efficient LTR transactivation by cellular TF and viral proteins is crucial for HIV-2 reactivation and viral production. Proviral LTRs from 66 antiretroviral-naive HIV-2-infected patients included in the French ANRS HIV-2 CO5 Cohort were sequenced.
View Article and Find Full Text PDFHIV-1 poorly infects monocyte-derived dendritic cells (MDDCs). This is in large part due to SAMHD1, which restricts viral reverse transcription. Pseudotyping HIV-1 with vesicular stomatitis virus G protein (VSV-G) strongly enhances infection, suggesting that earlier steps of viral replication, including fusion, are also inefficient in MDDCs.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
May 2016
Viruses often interfere with the DNA damage response to better replicate in their hosts. The human immunodeficiency virus 1 (HIV-1) viral protein R (Vpr) protein has been reported to modulate the activity of the DNA repair structure-specific endonuclease subunit (SLX4) complex and to promote cell cycle arrest. Vpr also interferes with the base-excision repair pathway by antagonizing the uracil DNA glycosylase (Ung2) enzyme.
View Article and Find Full Text PDFJ Gynecol Obstet Biol Reprod (Paris)
September 2016
Objectives: Compare the number of consultations with the consultation's delay in relation with the sensation of decrease active fetal movements (AFM) in case of late pregnancy, according to the fact if the patients use or not the AFM's count.
Materials And Methods: We have compared a "control" group made up of 160 patients who received a classic information and observation (from December 18th, 2013 to February 28th, 2014) versus an "educated" group made up of 160 patients who have been educated to the AFM count (from March 1st, 2014 to August 12th, 2014).
Results: The consultations for AFM decrease, were significantly more frequent in the "control" group than in the "educated" group (36 versus 8, P=0.
Increased IFN-α production contributes to the pathogenesis of infectious and autoimmune diseases. Plasmacytoid dendritic cells (pDCs) from females produce more IFN-α upon TLR7 stimulation than pDCs from males, yet the mechanisms underlying this difference remain unclear. In this article, we show that basal levels of IFN regulatory factor (IRF) 5 in pDCs were significantly higher in females compared with males and positively correlated with the percentage of IFN-α-secreting pDCs.
View Article and Find Full Text PDFJ Gynecol Obstet Biol Reprod (Paris)
April 2016
Objectives: Evaluate knowledge of patients with late pregnancy on active foetal movements.
Patients And Method: This prospective study has been carried out with volontary patients during the 41-week of gestation term consultation, with a questionnaire, at the obstetric gynecology departments of St-Etienne Hospital (CHU), Clermont-Ferrand Hospital (CHU), Roanne Hospital (CH) and Firminy Hospital (CH), from July 22nd, 2013 to September 14th, 2014.
Results: Few patients (17%) have been seen urgently by an obstetrician or a midwife in case of a decrease of the active foetal movements.
Unlabelled: Human immunodeficiency virus (HIV) in humans and simian immunodeficiency virus (SIV) in macaques (MAC) lead to chronic inflammation and AIDS. Natural hosts, such as African green monkeys (AGM) and sooty mangabeys (SM), are protected against SIV-induced chronic inflammation and AIDS. Here, we report that AGM plasmacytoid dendritic cells (pDC) express extremely low levels of CD4, unlike MAC and human pDC.
View Article and Find Full Text PDFAlthough plasmacytoid dendritic cells (pDCs) represent a rare immune cell type, they are the most important source of type I interferons (IFNs) upon viral infection. Phagocytosed RNA viruses and RNA virus-infected cells are detected by pDCs with the endosomal pattern recognition receptor (PRR) toll-like receptor 7 (TLR7). We showed that replication of the yellow fever live vaccine YF-17D in human pDCs and pDC-like cell lines stimulated type I IFN production through RIG-I (retinoic acid-inducible gene I), a member of the RIG-I-like receptor (RLR) family of cytosolic PRRs.
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