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1.
Aging (Albany NY) ; null2024 Sep 09.
Article de Anglais | MEDLINE | ID: mdl-39264580

RÉSUMÉ

Understanding the relationship between activity over the entire lifespan and longevity is an important facet of aging research. We present a comprehensive framework for the statistical analysis of longitudinal activity and behavioral monitoring and their relationship with age-at-death at the individual level, highlighting the importance of advanced methodological approaches in aging research. The focus is on animal models, where continuous monitoring activity in terms of movement, reproduction and behaviors over the entire lifespan is feasible at the individual level. We specifically demonstrate the methodology with data on activity monitoring for Mediterranean fruit flies. Advanced statistical methodologies to explore the interface between activity and age-at-death include functional principal component analysis, concurrent regression, Fréchet regression and point processes. While the focus of this perspective is on relating age-at-death with data on movement, reproduction, behavior and nutrition of Mediterranean fruit flies, the methodology equally pertains to data from other species, including human data.

2.
Pharmacol Biochem Behav ; 242: 173823, 2024 Sep.
Article de Anglais | MEDLINE | ID: mdl-39002804

RÉSUMÉ

PURPOSE: For understanding the neurochemical mechanism of neuropsychiatric conditions associated with cognitive deficits it is of major relevance to elucidate the influence of serotonin (5-HT) agonists and antagonists on memory function as well dopamine (DA) and 5-HT release and metabolism. In the present study, we assessed the effects of the 5-HT2A receptor agonist 2,5-dimethoxy-4-iodoamphetamine (DOI) and the 5-HT2A receptor altanserin (ALT) on object and place recognition memory and cerebral neurotransmitters and metabolites in the rat. METHODS: Rats underwent a 5-min exploration trial in an open field with two identical objects. After systemic injection of a single dose of either DOI (0.1 mg/kg), ALT (1 mg/kg) or the respectice vehicle (0.9 % NaCl, 50 % DMSO), rats underwent a 5-min test trial with one of the objects replaced by a novel one and the other object transferred to a novel place. Upon the assessment of object exploration and motor/exploratory behaviors, rats were sacrificed. DA, 5-HT and metabolite levels were analyzed in cingulate (CING), caudateputamen (CP), nucleus accumbens (NAC), thalamus (THAL), dorsal (dHIPP) and ventral hippocampus (vHIPP), brainstem and cerebellum with high performance liquid chromatography. RESULTS: DOI decreased rearing but increased head-shoulder motility relative to vehicle. Memory for object and place after both DOI and ALT was not different from vehicle. Network analyses indicated that DOI inhibited DA metabolization in CING, CP, NAC, and THAL, but facilitated it in dHIPP. Likewise, DOI inhibited 5-HT metabolization in CING, NAC, and THAL. ALT facilitated DA metabolization in the CING, NAC, dHIPP, vHIPP, and CER, but inhibited it in the THAL. Additionally, ALT facilitated 5-HT metabolization in NAC and dHIPP. CONCLUSIONS: DOI and ALT differentially altered the quantitative relations between the neurotransmitter/metabolite levels in the individual brain regions, by inducing region-specific shifts in the metabolization pathways. Findings are relevant for understanding the neurochemistry underlying DAergic and/or 5-HTergic dysfunction in neurological and psychiatric conditions.


Sujet(s)
Amphétamines , Encéphale , Dopamine , Sérotonine , Animaux , Rats , Sérotonine/métabolisme , Mâle , Dopamine/métabolisme , Amphétamines/pharmacologie , Encéphale/métabolisme , Encéphale/effets des médicaments et des substances chimiques , Kétansérine/pharmacologie , Kétansérine/analogues et dérivés , Agonistes des récepteurs 5-HT2 de la sérotonine/pharmacologie , Rat Wistar
3.
Neurol Res Pract ; 6(1): 35, 2024 Jul 11.
Article de Anglais | MEDLINE | ID: mdl-38987823

RÉSUMÉ

OBJECTIVE: This study investigates the association of Body Mass Index (BMI) and age of epilepsy onset, in patients with epilepsy associated with temporal encephaloceles (TEs). METHODS: A comprehensive PubMed literature review was conducted using the keywords "temporal encephaloceles" and "epilepsy" for identifying articles for the analysis. Inclusion criteria encompassed all evidence levels reporting patients with TE-related epilepsy and documented BMI. Logistic regression analyses were performed to examine the effect of BMI on predicting epilepsy onset after the 25th year of age. Spearman's correlation assessed the relationship between BMI with epilepsy onset. Finally, the association between BMI and postsurgical outcomes, distinguishing between more favourable outcomes (Engel Class I and II) and less favourable outcomes (Engell Class III and IV) was explored. RESULTS: Of the initially identified 88 articles, nine were included in the analysis, involving 127 patients with TE-related epilepsy and reported BMI. The mean age of epilepsy onset was 24.9 years (SD = 14.8 years), with a mean BMI of 28.0 kg/m2 (SD = 7.4 kg/m2). A significant positive correlation was observed between BMI and age of epilepsy onset (rho = 0.448, p < 0.001). Female patients had higher BMI compared to male patients (30.1 kg/m2, SD = 8.7 kg/m2 and 26.5 kg/m2, SD = 5.3 kg/m2 respectively, p = 0.008). However, the epilepsy onset did not differ significantly between male and female patients (p = 0.26). The bivariate logistic regression showed that patients with increased BMI were more likely to have an epilepsy onset after the 25th year of age, adjusted for the confounder sex (OR = 1.133, 95%-CI [1.060, 1.211], p < 0.001). Finally, a potential trend indicated a higher average BMI among patients with more favourable postsurgical outcomes than less favourable postsurgical outcomes (27.3 kg/m2, SD = 7.7 kg/m2 and 24.8 kg/m2, SD = 2.2 kg/m2 respectively, p = 0.076).

4.
J R Stat Soc Series B Stat Methodol ; 86(3): 694-713, 2024 Jul.
Article de Anglais | MEDLINE | ID: mdl-39005888

RÉSUMÉ

Quantifying the association between components of multivariate random curves is of general interest and is a ubiquitous and basic problem that can be addressed with functional data analysis. An important application is the problem of assessing functional connectivity based on functional magnetic resonance imaging (fMRI), where one aims to determine the similarity of fMRI time courses that are recorded on anatomically separated brain regions. In the functional brain connectivity literature, the static temporal Pearson correlation has been the prevailing measure for functional connectivity. However, recent research has revealed temporally changing patterns of functional connectivity, leading to the study of dynamic functional connectivity. This motivates new similarity measures for pairs of random curves that reflect the dynamic features of functional similarity. Specifically, we introduce gradient synchronization measures in a general setting. These similarity measures are based on the concordance and discordance of the gradients between paired smooth random functions. Asymptotic normality of the proposed estimates is obtained under regularity conditions. We illustrate the proposed synchronization measures via simulations and an application to resting-state fMRI signals from the Alzheimer's Disease Neuroimaging Initiative and they are found to improve discrimination between subjects with different disease status.

5.
Neuroimage Clin ; 43: 103633, 2024 Jun 14.
Article de Anglais | MEDLINE | ID: mdl-38889523

RÉSUMÉ

OBJECTIVE: The corticospinal tract (CST) reveals progressive microstructural alterations in ALS measurable by DTI. The aim of this study was to evaluate fractional anisotropy (FA) along the CST as a longitudinal marker of disease progression in ALS. METHODS: The study cohort consisted of 114 patients with ALS and 110 healthy controls from the second prospective, longitudinal, multicentre study of the Canadian ALS Neuroimaging Consortium (CALSNIC-2). DTI and clinical data from a harmonized protocol across 7 centres were collected. Thirty-nine ALS patients and 61 controls completed baseline and two follow-up visits and were included for longitudinal analyses. Whole brain-based spatial statistics and hypothesis-guided tract-of-interest analyses were performed for cross-sectional and longitudinal analyses. RESULTS: FA was reduced at baseline and longitudinally in the CST, mid-corpus callosum (CC), frontal lobe, and other ALS-related tracts, with alterations most evident in the CST and mid-CC. CST and pontine FA correlated with functional impairment (ALSFRS-R), upper motor neuron function, and clinical disease progression rate. Reduction in FA was largely located in the upper CST; however, the longitudinal decline was greatest in the lower CST. Effect sizes were dependent on region, resulting in study group sizes between 17 and 31 per group over a 9-month interval. Cross-sectional effect sizes were maximal in the upper CST; whereas, longitudinal effect sizes were maximal in mid-callosal tracts. CONCLUSIONS: Progressive microstructural alterations in ALS are most prominent in the CST and CC. DTI can provide a biomarker of cerebral degeneration in ALS, with longitudinal changes in white matter demonstrable over a reasonable observation period, with a feasible number of participants, and within a multicentre framework.

6.
Article de Anglais | MEDLINE | ID: mdl-38884774

RÉSUMÉ

PURPOSE: While fMRI provides information on the temporal changes in blood oxygenation, 2- [18F]fluoro-2-deoxy-D-glucose ([18F]FDG)-PET has traditionally offered a static snapshot of brain glucose consumption. As a result, studies investigating metabolic brain networks as potential biomarkers for neurodegeneration have primarily been conducted at the group level. However, recent pioneering studies introduced time-resolved [18F]FDG-PET with constant infusion, which enables metabolic connectivity studies at the individual level. METHODS: In the current study, this technique was employed to explore Parkinson's disease (PD)-related alterations in individual metabolic connectivity, in comparison to inter-subject measures and hemodynamic connectivity. Fifteen PD patients and 14 healthy controls with comparable cognition underwent sequential resting-state dynamic PET with constant infusion and functional MRI. Intrinsic networks were identified by independent component analysis and interregional connectivity calculated for summed static PET images, PET time series and functional MRI. RESULTS: Our findings revealed an intrinsic sensorimotor network in PD patients that has not been previously observed to this extent. In PD, a significantly higher number of connections in cortical motor areas was observed compared to elderly control subjects, as indicated by both static PET and functional MRI (pBonferroni-Holm = 0.027), as well as constant infusion PET and functional MRI connectomes (pBonferroni-Holm = 0.012). This intensified coupling was associated with disease severity (ρ = 0.56, p = 0.036). CONCLUSION: Metabolic connectivity, as revealed by both static and dynamic PET, provides unique information on metabolic network activity. Subject-level metabolic connectivity based on constant infusion PET may serve as a potential marker for the metabolic network signature in neurodegeneration.

7.
Behav Brain Res ; 469: 115051, 2024 07 09.
Article de Anglais | MEDLINE | ID: mdl-38777263

RÉSUMÉ

Both dopamine (DA) and serotonin (5-HT) play key roles in numerous functions including motor control, stress response and learning. So far, there is scarce or conflicting evidence about the effects of 5-HT1A and 5-HT2A receptor (R) agonists and antagonists on recognition memory in the rat. This also holds for their effect on cerebral DA as well as 5-HT release. In the present study, we assessed the effects of the 5-HT1AR agonist 8-OH-DPAT and antagonist WAY100,635 and the 5-HT2AR agonist DOI and antagonist altanserin (ALT) on rat behaviors. Moreover, we investigated their impact on monoamine efflux by measuring monoamine transporter binding in various regions of the rat brain. After injection of either 8-OH-DPAT (3 mg/kg), WAY100,635 (0.4 mg/kg), DOI (0.1 mg/kg), ALT (1 mg/kg) or the respective vehicle (saline, DMSO), rats underwent an object and place recognition memory test in the open field. Upon the assessment of object exploration, motor/exploratory parameters and feces excretion, rats were administered the monoamine transporter radioligand N-o-fluoropropyl-2b-carbomethoxy-3b-(4-[123I]iodophenyl)-nortropane ([123I]-FP-CIT; 8.9 ± 2.6 MBq) into the tail vein. Regional radioactivity accumulations in the rat brain were determined post mortem. Compared vehicle, administration of 8-OH-DPAT impaired memory for place, decreased rearing behavior, and increased ambulation as well as head-shoulder movements. DOI administration led to a reduction in rearing behavior but an increase in head-shoulder motility relative to vehicle. Feces excretion was diminished after ALT relative to vehicle. Dopamine transporter (DAT) binding was increased in the caudateputamen (CP), but decreased in the nucleus accumbens (NAC) after 8-OH-DPAT relative to vehicle. Moreover, DAT binding was decreased in the NAC after ALT relative to vehicle. Findings indicate that 5-HT1AR inhibition and 5-HT2AR activation may impair memory for place. Furthermore, results imply associations not only between recognition memory, motor/exploratory behavior and emotionality but also between the respective parameters and the levels of available DA in CP and NAC.


Sujet(s)
Transporteurs de la dopamine , Comportement d'exploration , , Animaux , Transporteurs de la dopamine/métabolisme , Mâle , /effets des médicaments et des substances chimiques , /physiologie , Comportement d'exploration/effets des médicaments et des substances chimiques , Comportement d'exploration/physiologie , Rats , Récepteur de la sérotonine de type 5-HT1A/métabolisme , Récepteur de la sérotonine de type 5-HT1A/effets des médicaments et des substances chimiques , Récepteur de la sérotonine de type 5-HT2A/métabolisme , Récepteur de la sérotonine de type 5-HT2A/effets des médicaments et des substances chimiques , Activité motrice/effets des médicaments et des substances chimiques , Activité motrice/physiologie , Encéphale/métabolisme , Encéphale/effets des médicaments et des substances chimiques , Émotions/effets des médicaments et des substances chimiques , Émotions/physiologie , Agonistes des récepteurs 5-HT1 de la sérotonine/pharmacologie , Agonistes des récepteurs 5-HT2 de la sérotonine/pharmacologie , Rat Wistar
8.
Genetics ; 227(1)2024 05 07.
Article de Anglais | MEDLINE | ID: mdl-38573366

RÉSUMÉ

WormBase has been the major repository and knowledgebase of information about the genome and genetics of Caenorhabditis elegans and other nematodes of experimental interest for over 2 decades. We have 3 goals: to keep current with the fast-paced C. elegans research, to provide better integration with other resources, and to be sustainable. Here, we discuss the current state of WormBase as well as progress and plans for moving core WormBase infrastructure to the Alliance of Genome Resources (the Alliance). As an Alliance member, WormBase will continue to interact with the C. elegans community, develop new features as needed, and curate key information from the literature and large-scale projects.


Sujet(s)
Caenorhabditis elegans , Caenorhabditis elegans/génétique , Animaux , Bases de données génétiques , Génome d'helminthe , Génomique/méthodes
9.
Front Hum Neurosci ; 18: 1378896, 2024.
Article de Anglais | MEDLINE | ID: mdl-38628970

RÉSUMÉ

Neuroimaging biomarkers have shown high potential to map the disease processes in the application to neurodegenerative diseases (NDD), e.g., diffusion tensor imaging (DTI). For DTI, the implementation of a standardized scanning and analysis cascade in clinical trials has potential to be further optimized. Over the last few years, various approaches to improve DTI applications to NDD have been developed. The core issue of this review was to address considerations and limitations of DTI in NDD: we discuss suggestions for improvements of DTI applications to NDD. Based on this technical approach, a set of recommendations was proposed for a standardized DTI scan protocol and an analysis cascade of DTI data pre-and postprocessing and statistical analysis. In summary, considering advantages and limitations of the DTI in NDD we suggest improvements for a standardized framework for a DTI-based protocol to be applied to future imaging studies in NDD, towards the goal to proceed to establish DTI as a biomarker in clinical trials in neurodegeneration.

10.
Int J Comput Assist Radiol Surg ; 19(8): 1579-1587, 2024 Aug.
Article de Anglais | MEDLINE | ID: mdl-38536565

RÉSUMÉ

PURPOSE: Motor neuron disease (MND) causes damage to the upper and lower motor neurons including the motor cranial nerves, the latter resulting in bulbar involvement with atrophy of the tongue muscle. To measure tongue atrophy, an operator independent automatic segmentation of the tongue is crucial. The aim of this study was to apply convolutional neural network (CNN) to MRI data in order to determine the volume of the tongue. METHODS: A single triplanar CNN of U-Net architecture trained on axial, coronal, and sagittal planes was used for the segmentation of the tongue in MRI scans of the head. The 3D volumes were processed slice-wise across the three orientations and the predictions were merged using different voting strategies. This approach was developed using MRI datasets from 20 patients with 'classical' spinal amyotrophic lateral sclerosis (ALS) and 20 healthy controls and, in a pilot study, applied to the tongue volume quantification to 19 controls and 19 ALS patients with the variant progressive bulbar palsy (PBP). RESULTS: Consensus models with softmax averaging and majority voting achieved highest segmentation accuracy and outperformed predictions on single orientations and consensus models with union and unanimous voting. At the group level, reduction in tongue volume was not observed in classical spinal ALS, but was significant in the PBP group, as compared to controls. CONCLUSION: Utilizing single U-Net trained on three orthogonal orientations with consequent merging of respective orientations in an optimized consensus model reduces the number of erroneous detections and improves the segmentation of the tongue. The CNN-based automatic segmentation allows for accurate quantification of the tongue volumes in all subjects. The application to the ALS variant PBP showed significant reduction of the tongue volume in these patients and opens the way for unbiased future longitudinal studies in diseases affecting tongue volume.


Sujet(s)
Imagerie par résonance magnétique , Maladies du motoneurone , , Langue , Humains , Langue/imagerie diagnostique , Imagerie par résonance magnétique/méthodes , Maladies du motoneurone/imagerie diagnostique , Maladies du motoneurone/diagnostic , Mâle , Femelle , Adulte d'âge moyen , Sujet âgé , Projets pilotes , Imagerie tridimensionnelle/méthodes , Sclérose latérale amyotrophique/imagerie diagnostique , Sclérose latérale amyotrophique/diagnostic , Adulte
11.
J Neurol Neurosurg Psychiatry ; 95(8): 737-747, 2024 Jul 15.
Article de Anglais | MEDLINE | ID: mdl-38388486

RÉSUMÉ

BACKGROUND: Validation of the 2020 consensus criteria for primary lateral sclerosis (PLS) is essential for their use in clinical practice and future trials. METHODS: In a large cohort of patients diagnosed with PLS by expert opinion prior to the new criteria with detailed clinical baseline evaluation (n=107) and longitudinal follow-up (n=63), we applied the new diagnostic criteria and analysed the clinical phenotype, electromyography (EMG), diagnostic accuracy and prognosis, adding neurofilaments and MRI as potential biomarkers. RESULTS: The criteria for definite PLS were met by 28% and those for probable PLS by 19%, whereas 53% did not meet the full criteria at baseline, mainly due to the time, EMG and region criteria. Patients not meeting the criteria had less generalised upper motor neuron involvement but were otherwise similar in demographic and clinical characteristics. All patients with definite and probable PLS maintained PLS diagnosis during follow-up, while four patients not meeting the criteria developed clinical lower motor neuron involvement. Definite PLS cases showed improved survival compared with probable PLS and patients who did not meet the criteria. Despite a clinical PLS phenotype, fibrillation potentials/positive sharp waves and fasciculations in one or more muscles were a frequent EMG finding, with the extent and prognostic significance depending on disease duration. Serum neurofilament light and a multiparametric MRI fibre integrity Z-score correlated with clinical parameters and were identified as potential biomarkers. CONCLUSION: Validation of the 2020 PLS consensus criteria revealed high diagnostic certainty and prognostic significance, supporting their value for research and clinical practice.


Sujet(s)
Consensus , Électromyographie , Imagerie par résonance magnétique , Maladies du motoneurone , Humains , Femelle , Mâle , Adulte d'âge moyen , Maladies du motoneurone/diagnostic , Études de cohortes , Adulte , Sujet âgé , Protéines neurofilamenteuses/sang , Marqueurs biologiques/sang , Pronostic
12.
Ann Clin Transl Neurol ; 11(4): 1000-1010, 2024 Apr.
Article de Anglais | MEDLINE | ID: mdl-38356047

RÉSUMÉ

OBJECTIVE: Monosynaptically cortically innervated α-motoneurons are early and strongly involved in amyotrophic lateral sclerosis (ALS). Consequently, the muscles that receive the strongest direct corticomotoneuronal input are the clinically most affected. To objectify this concept in vivo through morphological image correlates, whole-body magnetic resonance imaging (MRI) with muscle signal analysis was performed in patients with ALS compared to healthy controls. METHODS: Modified Dixon-based whole-body MRI was acquired in patients with ALS (n = 33) and matched healthy controls (n = 30). Manual labeling of limb muscle MRI was performed, and a specific subset of nine muscles, selected as pairs of muscle groups with different corticomotoneuronal input, was analyzed per subject based on their volume, fat fraction, and functional remaining muscle area (fRMA). RESULTS: Statistical analysis of 978 muscles in total revealed significantly decreased volumes, decreased fRMA, and increased fat fraction in the muscles of patients with ALS compared to controls. The clinical degree of pareses of directly innervated muscles was significantly worse than that of less directly innervated muscles in each comparison. The muscles receiving stronger direct corticomotoneuronal input showed more pronounced morphological involvement compared to those with less monosynaptic corticomotoneuronal input (fRMA, significant in three pairwise comparisons). INTERPRETATION: In conclusion, whole-body MRI-based muscle analysis provided additional evidence for a characteristic pattern of pareses in ALS. This technical approach (parameterization and quantification of muscle alterations from MRI) to patients with ALS could pave the way for the future establishment of a diagnostic algorithm of muscle MRI for ALS and may serve as a biomarker.


Sujet(s)
Sclérose latérale amyotrophique , Imagerie par résonance magnétique , Humains , Imagerie par résonance magnétique/méthodes , Sclérose latérale amyotrophique/imagerie diagnostique , Sclérose latérale amyotrophique/anatomopathologie , Imagerie du corps entier , Muscles squelettiques/anatomopathologie , Parésie
13.
Clin Nephrol ; 101(4): 171-180, 2024 Apr.
Article de Anglais | MEDLINE | ID: mdl-38329918

RÉSUMÉ

INTRODUCTION: Hemoglobin (Hb) variability occurs frequently in hemodialysis (HD) patients during erythropoietin (EPO) therapy. Guidelines define a narrow target range for the anemia treatment in these patients that is difficult to adhere to in practice. Our aim was to evaluate whether the Hb variability in HD patients is higher compared to non-chronic kidney disease or end-stage renal disease (ESRD) participants and patients with CKD stage I or II. MATERIALS AND METHODS: Monthly blood samples were assessed prospectively in 100 non-CKD or ESRD participants and 57 patients with CKD stage I or II, and retrospectively in 74 HD patients without changes in EPO or iron dose for 6 months. Variability was calculated and compared between the different groups. RESULTS: Hb variability was significantly higher in HD patients compared to the other groups, corresponding to results of previous studies. There were no significant differences between non-CKD or ESRD participants and patients with CKD stage I or II in terms of standard deviation (SD), residual SD, fluctuations across threshold, Hb cycling, and mean absolute change of Hb every 30 days (p > 0.05), but a significant difference compared to HD patients (p < 0.001). There were no significant differences between the groups in time in target and area under the curve (AUC) (p > 0.05). CONCLUSION: Hb variability is a common phenomenon in all groups independently of the method used for assessment and even without EPO therapy. The target range is difficult to achieve for HD patients and should be reconsidered in the future to avoid unsettling both the patients and the staff.


Sujet(s)
Anémie , Érythropoïétine , Défaillance rénale chronique , Insuffisance rénale chronique , Humains , Études rétrospectives , Défaillance rénale chronique/complications , Défaillance rénale chronique/thérapie , Hémoglobines/analyse , Érythropoïétine/usage thérapeutique , Insuffisance rénale chronique/thérapie , Insuffisance rénale chronique/traitement médicamenteux , Anémie/traitement médicamenteux , Anémie/étiologie , Dialyse rénale
14.
Aging Cell ; 23(4): e14080, 2024 04.
Article de Anglais | MEDLINE | ID: mdl-38268242

RÉSUMÉ

The relationship between the early-age activity of Mediterranean fruit flies (medflies) or other fruit flies and their lifespan has not been much studied, in contrast to the connections between lifespan and diet, sexual signaling, and reproduction. The objective of this study is to assess intra-day and day-to-day activity profiles of female Mediterranean fruit flies and their role as biomarker of longevity as well as to explore the relationships between these activity profiles, diet, and age-at-death throughout the lifespan. We use advanced statistical methods from functional data analysis (FDA). Three distinct patterns of activity variations in early-age activity profiles can be distinguished. A low-caloric diet is associated with a delayed activity peak, while a high-caloric diet is linked with an earlier activity peak. We find that age-at-death of individual medflies is connected to their activity profiles in early life. An increased risk of mortality is associated with increased activity in early age, as well as with a higher contrast between daytime and nighttime activity. Conversely, medflies are more likely to have a longer lifespan when they are fed a medium-caloric diet and when their daily activity is more evenly distributed across the early-age span and between daytime and nighttime. The before-death activity profile of medflies displays two characteristic before-death patterns, where one pattern is characterized by slowly declining daily activity and the other by a sudden decline in activity that is followed by death.


Sujet(s)
Ceratitis capitata , Longévité , Animaux , Femelle , Vieillissement , Reproduction , Drosophila , Marqueurs biologiques
15.
Article de Anglais | MEDLINE | ID: mdl-38269325

RÉSUMÉ

INTRODUCTION: Breastfeeding to strengthen the immune system suggests allergy prevention as a possible option. The connection between breastfeeding and the development of atopic-allergic diseases is being discussed. The primary aim of this work was to investigate an association of the first early skin-to-skin contact following cesarean section with the development of atopic diseases within the 1st year of life. METHODS: The present study was conducted as a bicentric prospective cohort study in central Germany with a 15-month recruitment period. Data collection was by telephone interviews with a follow-up of 12 months. The statistical evaluation procedure was based on a hierarchical test of the association of early skin-to-skin contact between mother and child with the two main outcome measures. The primary outcome is the duration of breastfeeding. The second outcome is the onset of atopic-allergic disease within the 1st year of life. RESULTS: Mothers breastfed longer if they had skin-to-skin contact within the first 30 minutes postpartum [χ²(df=5) = 19.020, p=0.002], if they breastfed their newborns early immediately after birth (p<0.001), and if the first skin-to-skin contact lasted more than one hour [χ²(df=4) = 19.617, p<0.001]. Regarding atopic-allergic diseases, no significant effects of skin-to-skin contact were found in relation to disease development. Regarding breastfeeding, no significant effects of atopic-allergic diseases could be detected either. CONCLUSIONS: The results of this study reflect the benefits of skin-to-skin contact in the context of breastfeeding and atopic disease. The current scientific knowledge regarding skin contact and the development of atopic-allergic diseases should be extended and deepened.

16.
Elife ; 122024 Jan 22.
Article de Anglais | MEDLINE | ID: mdl-38252473

RÉSUMÉ

Fibroblast growth factor 2 (FGF2) exits cells by direct translocation across the plasma membrane, a type I pathway of unconventional protein secretion. This process is initiated by phosphatidylinositol-4,5-bisphosphate (PI(4,5)P2)-dependent formation of highly dynamic FGF2 oligomers at the inner plasma membrane leaflet, inducing the formation of lipidic membrane pores. Cell surface heparan sulfate chains linked to glypican-1 (GPC1) capture FGF2 at the outer plasma membrane leaflet, completing FGF2 membrane translocation into the extracellular space. While the basic steps of this pathway are well understood, the molecular mechanism by which FGF2 oligomerizes on membrane surfaces remains unclear. In the current study, we demonstrate the initial step of this process to depend on C95-C95 disulfide-bridge-mediated FGF2 dimerization on membrane surfaces, producing the building blocks for higher FGF2 oligomers that drive the formation of membrane pores. We find FGF2 with a C95A substitution to be defective in oligomerization, pore formation, and membrane translocation. Consistently, we demonstrate a C95A variant of FGF2 to be characterized by a severe secretion phenotype. By contrast, while also important for efficient FGF2 secretion from cells, a second cysteine residue on the molecular surface of FGF2 (C77) is not involved in FGF2 oligomerization. Rather, we find C77 to be part of the interaction interface through which FGF2 binds to the α1 subunit of the Na,K-ATPase, the landing platform for FGF2 at the inner plasma membrane leaflet. Using cross-linking mass spectrometry, atomistic molecular dynamics simulations combined with a machine learning analysis and cryo-electron tomography, we propose a mechanism by which disulfide-bridged FGF2 dimers bind with high avidity to PI(4,5)P2 on membrane surfaces. We further propose a tight coupling between FGF2 secretion and the formation of ternary signaling complexes on cell surfaces, hypothesizing that C95-C95-bridged FGF2 dimers are functioning as the molecular units triggering autocrine and paracrine FGF2 signaling.


Sujet(s)
Espace extracellulaire , Facteur de croissance fibroblastique de type 2 , Dimérisation , Sodium-Potassium-Exchanging ATPase , Disulfures
17.
Obesity (Silver Spring) ; 32(1): 156-165, 2024 Jan.
Article de Anglais | MEDLINE | ID: mdl-37817330

RÉSUMÉ

OBJECTIVE: Common obesity-associated genetic variants at the fat mass and obesity-associated (FTO) locus have been associated with appetitive behaviors and altered structure and function of frontostriatal brain regions. The authors aimed to investigate the influence of FTO variation on frontostriatal appetite circuits in early life. METHODS: Data were drawn from RESONANCE, a longitudinal study of early brain development. Growth trajectories of nucleus accumbens and frontal lobe volumes, as well as total gray matter and white matter volume, by risk allele (AA) carrier status on FTO single-nucleotide polymorphism rs9939609 were examined in 228 children (102 female, 126 male) using magnetic resonance imaging assessments obtained from infancy through middle childhood. The authors fit functional concurrent regression models with brain volume outcomes over age as functional responses, and FTO genotype, sex, BMI z score, and maternal education were included as predictors. RESULTS: Bootstrap pointwise 95% CI for regression coefficient functions in the functional concurrent regression models showed that the AA group versus the group with no risk allele (TT) had greater nucleus accumbens volume (adjusted for total brain volume) in the interval of 750 to 2250 days (2-6 years). CONCLUSIONS: These findings suggest that common genetic risk for obesity is associated with differences in early development of brain reward circuitry and argue for investigating dynamic relationships among genotype, brain, behavior, and weight throughout development.


Sujet(s)
Obésité , Polymorphisme de nucléotide simple , Humains , Mâle , Enfant , Femelle , Études longitudinales , Obésité/génétique , Obésité/complications , Facteurs de risque , Génotype , Encéphale/imagerie diagnostique , Alpha-ketoglutarate-dependent dioxygenase FTO/génétique , Indice de masse corporelle , Prédisposition génétique à une maladie
18.
Rofo ; 196(1): 36-51, 2024 Jan.
Article de Anglais | MEDLINE | ID: mdl-37467779

RÉSUMÉ

BACKGROUND: Arterial spin labeling (ASL) is a magnetic resonance imaging (MRI)-based technique using labeled blood-water of the brain-feeding arteries as an endogenous tracer to derive information about brain perfusion. It enables the assessment of cerebral blood flow (CBF). METHOD: This review aims to provide a methodological and technical overview of ASL techniques, and to give examples of clinical use cases for various diseases affecting the central nervous system (CNS). There is a special focus on recent developments including super-selective ASL (ssASL) and time-resolved ASL-based magnetic resonance angiography (MRA) and on diseases commonly not leading to characteristic alterations on conventional structural MRI (e. g., concussion or migraine). RESULTS: ASL-derived CBF may represent a clinically relevant parameter in various pathologies such as cerebrovascular diseases, neoplasms, or neurodegenerative diseases. Furthermore, ASL has also been used to investigate CBF in mild traumatic brain injury or migraine, potentially leading to the establishment of imaging-based biomarkers. Recent advances made possible the acquisition of ssASL by selective labeling of single brain-feeding arteries, enabling spatial perfusion territory mapping dependent on blood flow of a specific preselected artery. Furthermore, ASL-based MRA has been introduced, providing time-resolved delineation of single intracranial vessels. CONCLUSION: Perfusion imaging by ASL has shown promise in various diseases of the CNS. Given that ASL does not require intravenous administration of a gadolinium-based contrast agent, it may be of particular interest for investigations in pediatric cohorts, patients with impaired kidney function, patients with relevant allergies, or patients that undergo serial MRI for clinical indications such as disease monitoring. KEY POINTS: · ASL is an MRI technique that uses labeled blood-water as an endogenous tracer for brain perfusion imaging.. · It allows the assessment of CBF without the need for administration of a gadolinium-based contrast agent.. · CBF quantification by ASL has been used in several pathologies including brain tumors or neurodegenerative diseases.. · Vessel-selective ASL methods can provide brain perfusion territory mapping in cerebrovascular diseases.. · ASL may be of particular interest in patient cohorts with caveats concerning gadolinium administration..


Sujet(s)
Angiopathies intracrâniennes , Migraines , Maladies neurodégénératives , Humains , Enfant , Produits de contraste , Marqueurs de spin , Gadolinium , Imagerie par résonance magnétique/méthodes , Artères , Angiographie par résonance magnétique/méthodes , Angiopathies intracrâniennes/imagerie diagnostique , Eau
19.
Am J Clin Nutr ; 119(1): 136-144, 2024 Jan.
Article de Anglais | MEDLINE | ID: mdl-37926191

RÉSUMÉ

BACKGROUND: Adherence to a Mediterranean-style dietary pattern is likely to have variable effects on body composition, but the impact of gut microbiome on this relationship is unknown. OBJECTIVES: To examine the potential mediating effect of the gut microbiome on the associations between Alternate Mediterranean Diet (aMed) scores, abdominal adiposity, and inflammation in population-level analysis. DESIGN: In a community-based sample aged 25 to 83 y (n = 620; 41% female) from Northern Germany, we assessed the role of the gut microbiome, sequenced from 16S rRNA genes, on the associations between aMed scores, estimated using validated food-frequency questionnaires, magnetic resonance imaging-determined visceral (VAT) and subcutaneous (SAT) adipose tissue and C-reactive protein (CRP). RESULTS: Higher aMed scores were associated with lower SAT (-0.86 L (95% CI: -1.56, -0.17), P = 0.01), VAT (-0.65 L (95% CI: -1.03,-0.27), P = 0.01) and CRP concentrations (-0.35 mg/L; ß: -20.1% (95% CI: 35.5, -1.09), P = 0.04) in the highest versus lowest tertile after multivariate adjustment. Of the taxa significantly associated with aMed scores, higher abundance of Porphyromonadaceae mediated 11.6%, 9.3%, and 8.7% of the associations with lower SAT, VAT, and CRP, respectively. Conversely, a lower abundance of Peptostreptococcaceae mediated 13.1% and 18.2% of the association with SAT and CRP levels. Of the individual components of the aMed score, moderate alcohol intake was associated with lower VAT (-0.2 (95% CI: -0.4, -0.1), P =0.01) with a higher abundance of Oxalobacteraceae and lower abundance of Burkholderiaceae explaining 8.3% and 9.6% of this association, respectively. CONCLUSION: These novel data suggest that abundance of specific taxa in the Porphyromonadaceae and Peptostreptococcaceae families may contribute to the association between aMed scores, lower abdominal adipose tissue, and inflammation.


Sujet(s)
Régime méditerranéen , Microbiome gastro-intestinal , Humains , Femelle , Mâle , Protéine C-réactive/métabolisme , Adiposité , ARN ribosomique 16S , Obésité abdominale/métabolisme , Inflammation/métabolisme , Graisse intra-abdominale/métabolisme
20.
Mov Disord ; 39(1): 53-63, 2024 Jan.
Article de Anglais | MEDLINE | ID: mdl-37955157

RÉSUMÉ

BACKGROUND: Reduced gastric motility in Parkinson's disease (PD) has been reported, but hardly any study exists in subjects with isolated rapid-eye-movement (REM) sleep behavior disorder (iRBD), a specific prodrome of α-synucleinopathies. OBJECTIVES: We compared the gastric motility of 17 iRBD subjects with that of 18 PD subjects (15 drug naive, 3 early treated in defined off) and 15 healthy controls (HC) with real-time magnetic resonance imaging (rtMRI). METHODS: After overnight fasting, participants consumed a standardized breakfast and underwent a 3-T rtMRI of the stomach. Amplitude and velocity of the peristaltic waves were analyzed under blinded conditions. Gastric motility index (GMI) was calculated. The procedure was repeated in 12 of 17 iRBD subjects ~2.5 years later. Nine of these 12 iRBD subjects were hyposmic. RESULTS: In iRBD and PD subjects the amplitude of the peristaltic waves was significantly reduced compared with HCs (iRBD vs. HC: 8.7 ± 3.7 vs. 11.9 ± 4.1 mm, P = 0.0097; PD vs. HC: 6.8 ± 2.2 vs. 11.9 ± 4.1 mm, P = 0.0001). The amplitude in iRBD and PD subjects was decreased to the same extent. The GMI was reduced in only PD subjects (PD vs. HC: P = 0.0027; PD vs. iRBD: P = 0.0203). After ~2.5 years the amplitude in iRBD subjects did not significantly decrease further. CONCLUSION: The amplitude of the peristaltic waves was markedly reduced in iRBD, a prodrome of α-synucleinopathies. This reduction was similar to the extent observed already in manifest early PD. This finding implies that the α-synuclein pathology affects the innervation of the stomach already in the prodromal stage. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.


Sujet(s)
Maladie de Parkinson , Trouble du comportement en sommeil paradoxal , Synucléinopathies , Humains , Maladie de Parkinson/complications , Maladie de Parkinson/anatomopathologie , Trouble du comportement en sommeil paradoxal/anatomopathologie , Estomac/anatomopathologie , Sommeil
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