Introduction Although South Africa adopted the World Health Organizations Test and Treat strategy for HIV epidemic control in 2016, antiretroviral therapy (ART) treatment initiation and retention remain below target. In 2017, an estimated 56.3% of men living with HIV were on ART. We aimed to investigate factors associated with non-use of ART among men in South Africa. Methods Utilizing data from the fifth South African National HIV Prevalence, Incidence, Behavior and Communication (SABSSM V) cross-sectional survey conducted in 2017, a subset of data from HIV-positive men was stratified based on presence/absence of antiretroviral drugs (ARVs) detected in dried blood spot samples. Data were weighted to be representative of the national population and analyzed using multivariable logistic regression to assess predictors of non-use of ART; p<0.05 was considered significant. Results A total of 6,920 men aged [≥]15 years old were enrolled in the study, of whom 953 (13.8%) tested HIV-positive. Among those HIV-positive, 810 (85%) had a known ARV test result: 470 (58%) had ARVs detected, and 340 (42%) did not have ARVs detected. Non-use of ART in men was associated with high-risk alcohol use (adjusted odds ratio (AOR)=3.68, 95% confidence interval (CI): 1.03-13.23), being a widower compared to being unmarried (AOR=6.99, 95%CI: 1.46-33.42), and having drug-resistant HIV (AOR=28.12, 95%CI: 13.89-56.94). Per year increase in age (AOR=0.67, 95%CI: 0.47-0.96), residence in rural tribal localities compared to urban localities (AOR=0.38, 95%CI: 0.18-0.78), or having a co-morbidity such as tuberculosis or diabetes (AOR=0.06, 95%CI: 0.03-0.14) were positively associated with ART use. Conclusions Non-use of ART was strongly associated with HIV drug resistance. Young men who are living with HIV, those with high-risk alcohol use, and widowers, should be a priority for HIV programming and linkage to care. Identifying interventions that are effective at linking these men to ART will help reduce the burden of HIV in South Africa. | Make paid
Leaves are colonised by a complex mix of microbes, termed the leaf microbiota. Even though the leaf microbiota is increasingly recognised as an integral part of plant life and health, our understanding of its interactions with the plant host is still limited. Here, mature, axenically grown Arabidopsis thaliana plants were spray-inoculated with six diverse leaf-colonising bacteria. The transcriptomic changes in leaves were tracked over time and significant changes in ethylene marker (ARL2) expression were observed only two to four days after spray-inoculation. Whole transcriptome sequencing revealed that four days after inoculation, leaf transcriptional changes to colonisation by non-pathogenic and pathogenic bacteria differed in strength but not in the type of response. Inoculation of plants with different densities of the non-pathogenic bacterium Williamsia sp. Leaf354 showed that high bacterial titers caused disease phenotypes and led to severe transcriptional reprogramming with a strong focus on plant defence. An in silico epigenetic analysis of the data was congruent with the transcriptomic analysis. These findings suggest (1) that plant responses are not rapid after spray-inoculation, (2) that plant responses only differ in strength and (3) that plants respond to high titers of non-pathogenic bacteria with pathogen-like responses. | Make paid
Bacterial mRNA sequencing is inefficient due to the abundance of ribosomal RNA that is challenging to deplete. While commercial kits target rRNA from common bacterial species, they are frequently inefficient when applied to divergent species, including those from environmental isolates. Similarly, other methods typically employ large probe sets that tile the entire length of rRNAs; however, such approaches are infeasible when applied to many species. Therefore, we present EMBR-seq+, which requires fewer than ten oligonucleotides per rRNA by combining rRNA blocking primers with RNase H-mediated depletion to achieve rRNA removal efficiencies of up to 99% in diverse bacterial species. Further, in more complex microbial co-cultures between F. succinogenes strain UWB7 and anerobic fungi, EMBR-seq+ depleted both bacterial and fungal rRNA, with a 4-fold improvement in bacterial rRNA depletion compared to a commercial kit, thereby demonstrating that the method can be applied to non-model microbial mixtures. Notably, for microbes with unknown rRNA sequences, EMBR-seq+ enables rapid iterations in probe design without requiring to start experiments from total RNA. Finally, efficient depletion of rRNA enabled systematic quantification of the reprogramming of the bacterial transcriptome when cultured in the presence of the anerobic fungi Anaeromyces robustus or Caecomyces churrovis. We observed that F. succinogenes strain UWB7 downregulated several lignocellulose-degrading carbohydrate-active enzymes in the presence of anerobic gut fungi, suggesting close interactions between two cellulolytic species that specialize in different aspects of biomass breakdown. Thus, EMBR-seq+ enables efficient, cost-effective and rapid quantification of the transcriptome to gain insights into non-model microbial systems. | Make paid
The ability to alter gene expression programs in response to changes in environmental conditions is central to the ability of an organism to thrive. For most organisms, the nervous system serves as the master regulator in communicating information about the animals surroundings to other tissues. The information relay centers on signaling pathways that cue transcription factors in a given cell type to execute a specific gene expression program, but also provide a means to signal between tissues. The transcription factor PQM-1 is an important mediator of the insulin signaling pathway contributing to longevity and the stress response as well as impacting survival from hypoxia. Herein, we reveal a novel mechanism for regulating PQM-1 expression specifically in neural cells of larval animals. Our studies reveal that the RNA binding protein, ADR-1, binds to pqm-1 mRNA in neural cells. This binding is regulated by the presence of a second RNA binding protein, ADR-2, which when absent leads to reduced expression of both pqm-1 and downstream PQM-1 activated genes. Interestingly, we find that neural pqm-1 expression is sufficient to impact gene expression throughout the animal and affect survival from hypoxia; phenotypes that we also observe in adr mutant animals. Together, these studies reveal an important post-transcriptional gene regulatory mechanism that allows the nervous system to sense and respond to environmental conditions to promote organismal survival from hypoxia. | Make paid
Background: Age is a significant risk factor for functional decline and disease of the musculoskeletal system, yet few biomarkers exist to facilitate ageing research in musculoskeletal tissues. Multivariate models based on DNA methylation, termed epigenetic clocks, have shown promise as markers of biological age. However, the accuracy of existing epigenetic clocks in musculoskeletal tissues are no more, and often less accurate than a randomly sampled baseline model. Results: We developed a highly accurate epigenetic clock, MskAge, that is specific to tissues and cells of the musculoskeletal system. MskAge was built using a penalised genetic algorithm islands model that addresses multi-tissue clock bias. The final model was trained on the transformed principal components of CpGs selected by the genetic algorithm, which are significantly enriched for pathways terms related to the skeletal system and mesenchyme development. We show that MskAge tracks epigenetic ageing ex vivo and in vitro. Epigenetic age estimates are rejuvenated to zero with cellular reprogramming and are accelerated at a rate of 0.45 years per population doubling. Remarkably, MskAge explains more variance associated with in vitro ageing of fibroblasts than the purpose-developed skin and blood clock. Conclusion: The precision of MskAge and its ability to capture perturbations in biological ageing make it a promising research tool for musculoskeletal and ageing biologists. | Make paid
Aging is characterized by changes in gene expression that drive deleterious cellular phenotypes leading to senescence. The transcriptional activation of senescence genes has been mainly attributed to epigenetic shifts, but the changes in chromatin accessibility and its underling mechanisms remain largely elusive in natural aging. Here, we profiled chromatin accessibility in human dermal fibroblasts (HDFs) from neonatal and octogenarian individuals. We found that AP-1 binding motifs are prevalent in elderly-specific accessible regions of the chromatin while neonatal-specific regions are highly enriched for TEAD binding motifs. We further show that TEAD4 and FOXM1 share a conserved transcriptional regulatory landscape controlled by an age-dependent enhancer that closes with aging and drives senescence when deleted. Finally, we demonstrate that FOXM1 ectopic expression in elderly cells partially resets chromatin accessibility to a youthful state due to FOXM1 repressive function in the promoters of several members of the AP-1 complex. These results place FOXM1 at a top hierarchical level in chromatin remodeling required to prevent senescence. | Make paid
Aging is characterized by a decline in tissue function, but the underlying changes at cellular resolution across the organism remain unclear. Here, we present the Aging Fly Cell Atlas, a single-nucleus transcriptomic map of the whole aging Drosophila. We characterize 163 distinct cell types and perform an in-depth analysis of changes in tissue cell composition, gene expression, and cell identities. We further develop aging clock models to predict the fly age and show that ribosomal gene expression is a conserved predictive factor for age. Combining all aging features, we find unique cell type-specific aging patterns. This atlas provides a valuable resource for studying fundamental principles of aging in complex organisms. | Make paid
Olfaction is one of the evolutionarily oldest senses and plays a fundamental role in foraging and social interactions across mammals. In primates, the role of olfaction is now well recognized, but better investigated in strepsirrhine and platyrrhine primates than in catarrhine primate species. We therefore observed the sniffing behavior of semi-free ranging Barbary macaques, Macaca sylvanus, at Affenberg Salem, Germany, to assess how frequently macaques use olfaction and in which contexts, and how olfaction is affected by sex and age. Focal observations of 24 males and 24 females aged 1 to 25 years showed that Barbary macaques sniffed, on average, 5.3 times per hour, with more than 80% of sniffs directed at food. Irrespective of the context, younger individuals used olfaction more often than older ones. Females sniffed more often on food than males did, while males used olfaction more often in a social context than females did. Sniffs at conspecifics primarily occurred in a sexual context, with 70% of social sniffs directed at female anogenital swellings performed by males. Of the observed 176 anogenital inspections, 51 involved sniffing of the swelling. Olfactory inspections were followed by copulation significantly less often than merely visual inspections, suggesting that anogenital odors provided additional information guiding male mating decisions. In sum, results show that Barbary macaques routinely use olfaction during feeding, but also in a social context. Our study further suggests that odors may guide mating decisions, but the role of olfaction in sexual interactions warrants further investigations. | Make paid
Carotenoids are isoprenoid pigments vital for photosynthesis. Moreover, they are the precursor of apocarotenoids that include the phytohormones abscisic acid (ABA) and strigolactones (SLs), and retrograde signaling molecules and growth regulators, such as {beta}-cyclocitral and zaxinone. The apocarotenoid {beta}-ionone ({beta}-I) was previously reported to exert antimicrobial effects. Here, we showed that the application of this scent to Arabidopsis plants at micromolar concentrations caused a global reprogramming of gene expression, affecting thousands of transcripts involved in stress tolerance, growth, hormone metabolism, pathogen defense and photosynthesis. These changes, along with modulating the levels of the phytohormones ABA, jasmonic acid and salicylic acid, led to enhanced Arabidopsis resistance to Botrytis cinerea (B.c.), one of the most aggressive and widespread pathogenic fungi affecting numerous plant hosts and causing severe losses of postharvest fruits. Pre-treatment of tobacco and tomato plants with {beta}-I followed by inoculation with B.c. confirms the conserved effect of {beta}-I and induced immune responses in leaves and fruits. Moreover, there was reduced susceptibility to B.c. in LYCOPENE {beta}-CYCLASE-expressing tomato fruits possessing elevated levels of the endogenous {beta}-I, indicating beneficial biological activities of this compound in planta. Our work unraveled {beta}-I as a further carotenoid-derived regulatory metabolite and opens up new possibilities to control B.c. infection by establishing this natural volatile as an environmentally friendly bio-fungicide. | Make paid
Constriction in the flow passage in the physiological circulatory system is central to the occurrence of several diseased conditions such as thrombosis and is also pivotal towards the understanding of several regulatory processes in the human microvasculature. It is, therefore, imperative to advance a mechanistic insight on the dynamics of the transiting cellular encapsulations in a physiologically-mimicking micro-confinement, with particular focus on deciphering the role of its mechano-physical properties. Here we bring out a quantitative depiction on the role of the membrane fluidity and the initial deflation (shape deviation from sphericity) of a lipid vesicle during its morphological transition from stretching to tumbling via rolling as it migrates across a microfluidic constriction. Based on our experimental observations as well as theoretical insights, we construct a regime map to elucidate the range of the key dimensionless parameters orchestrating the dynamic transition. Our results further bring out the role of the initial position of the lipid vesicle on its subsequent stretching dynamics, exhibiting characteristic nonlinearities and non-monotonic trends. In addition, our observations on the vesicles stretching dynamics emerge from mapping selectively with the viscosity contrast between the encapsulated and the suspending fluid medium, offering potential physiologically relevant cues on the impact of the aging of a cellular moiety on its deformability as it transits through a constricted path. Such mechanistic insights may potentially enable establishing quantitative correlations between the dynamical transition of a cellular encapsulation and its mechano-physical properties, which may in turn, have decisive implications in various states of health and disease while circulating across microvascular fluidic pathways. | Make paid
Although muscle atrophy may partially account for age-related strength decline, it is further influenced by alterations of neural input to muscle. Persistent inward currents and the level of common synaptic inputs to motoneurons influence neuromuscular function. However, these have not yet been described in aged human quadriceps. High density surface electromyography (HDsEMG) signals were collected from the vastus lateralis of 15 young (mean(SD), 23(5)y) and 15 older (67(9)y) men during submaximal sustained and 20s ramped contractions. HDsEMG signals were decomposed to identify individual motor unit discharges, from which delta F and intramuscular coherence were estimated. Older participants produced significantly lower knee extensor torque (p<0.001) and poorer force tracking ability (p<0.001) than young. Older participants also had lower delta F (p=0.001) and coherence estimates in the alpha frequency band (p<0.001) during ramp contractions when compared to young. Persistent inward currents and common synaptic inputs are lower in the vastus lateralis of older males when compared to young. These data highlight altered neural input to the clinically and functionally important quadriceps, further underpinning age-related loss of function which may occur independently of the loss of muscle mass. | Make paid
BACKGROUND: Gut microbiota have been implicated in atherosclerotic disease, but their relation with subclinical coronary atherosclerosis is unclear. This study aimed to identify associations between the gut microbiome and computed tomography-based measures of coronary atherosclerosis, and to explore relevant clinical correlates. METHODS: We conducted a cross-sectional study of 8973 participants aged 50 to 65 without overt atherosclerotic disease from the population-based Swedish Cardiopulmonary BioImage Study (SCAPIS). Coronary atherosclerosis was measured using coronary artery calcium score (CACS) and coronary computed tomography angiography (CCTA). Gut microbiota species abundance and functional potential were assessed with shotgun metagenomics sequencing of stool samples, and their association with coronary atherosclerosis was evaluated with multivariable regression models adjusted for cardiovascular risk factors. Associated species were evaluated for association with inflammatory markers, metabolites, and corresponding species in saliva. RESULTS: The mean age of the study sample was 57.4 years, and 53.7% were female. Coronary artery calcification was detected in 40.3% of participants, and 5.4% had at least one stenosis with more than 50% occlusion. Sixty-four species were associated with CACS independent of cardiovascular risk factors, with the strongest associations observed for Streptococcus anginosus and S. oralis subsp. oralis (P<1x10-5). Associations were largely similar across CCTA-based measurements. Out of the 64 species, 19 species, including streptococci and other species commonly found in the oral cavity, were associated with high-sensitivity C-reactive protein plasma concentrations and 16 with neutrophil counts. Oral species in the gut were negatively associated with plasma indole propionate and positively associated with plasma secondary bile acids and imidazole propionate. Five species correlated with the same species in saliva and were associated with worse dental health in the Malmo Offspring Dental Study. Microbial functional potential of dissimilatory nitrate reduction, anaerobic fatty acid beta-oxidation and amino acid degradation was associated with CACS. CONCLUSIONS: This study provides evidence of an association of a gut microbiota composition characterized by increased abundance of Streptococcus spp. and other species commonly found in the oral cavity with coronary atherosclerosis and systemic inflammation. Further longitudinal and experimental studies are warranted to explore the potential implication of a bacterial component in atherogenesis. | Make paid
Background Hypertrophic cardiomyopathy (HCM) is an important cause of sudden cardiac death associated with heterogeneous phenotypes but there is no systematic framework for classifying morphology or assessing associated risks. Here we quantitatively survey genotype-phenotype associations in HCM to derive a data-driven taxonomy of disease expression. Methods We enrolled 436 HCM patients (median age 60 years; 28.8% women) with clinical, genetic and imaging data. An independent cohort of 60 HCM patients from Singapore (median age 59 years; 11% women) and a reference population from UK Biobank (n = 16,691, mean age 55 years; 52.5% women) were also recruited. We used machine learning to analyse the three-dimensional structure of the left ventricle from cardiac magnetic resonance imaging and build a tree-based classification of HCM phenotypes. Genotype and mortality risk distributions were projected on the tree. Results Carriers of pathogenic or likely pathogenic variants for HCM (P/LP) variants had lower left ventricular mass, but greater basal septal hypertrophy, with reduced lifespan (mean follow-up 9.9 years) compared to genotype negative individuals (hazard ratio: 2.66; 95% confidence interval [CI]: 1.42-4.96; P < 0.002). Four main phenotypic branches were identified using unsupervised learning of three-dimensional shape: 1) non-sarcomeric hypertrophy with co-existing hypertension; 2) diffuse and basal asymmetric hypertrophy associated with outflow tract obstruction; 3) isolated basal hypertrophy; 4) milder non-obstructive hypertrophy enriched for familial sarcomeric HCM (odds ratio for P/LP variants: 2.18 [95% CI:1.93-2.28, P = 0.0001]). Polygenic risk for HCM was also associated with different patterns and degrees of disease expression. The model was generalisable to an independent cohort (trustworthiness M1: 0.86-0.88). Conclusions We report a data-driven taxonomy of HCM for identifying groups of patients with similar morphology while preserving a continuum of disease severity, genetic risk and outcomes. This approach will be of value in understanding the causes and consequences of disease diversity. | Make paid
Aged melanoma patients (>65 years old) have more aggressive disease relative to young patients (<55 years old) for reasons that are not completely understood. Analysis of the young and aged secretome from human dermal fibroblasts identified >5-fold levels of insulin-like growth factor binding protein 2 (IGFBP2) in the aged fibroblast secretome. IGFBP2 functionally triggers upregulation of the PI3K-dependent fatty acid biosynthesis program in melanoma cells through increases in FASN. Melanoma cells co-cultured with aged dermal fibroblasts have higher levels of lipids relative to young dermal fibroblasts, which can be lowered by silencing IGFBP2 expression in fibroblasts, prior to treating with conditioned media. Conversely, ectopically treating melanoma cells with recombinant IGFBP2 in the presence of conditioned media from young fibroblasts, promoted lipid synthesis and accumulation in the melanoma cells. Neutralizing IGFBP2 in vitro reduces migration and invasion in melanoma cells, and in vivo studies demonstrate that neutralizing IGFBP2 in syngeneic aged mice, ablates tumor growth as well as metastasis. Conversely, ectopic treatment of young mice with IGFBP2 in young mice increases tumor growth and metastasis. Our data reveal that aged dermal fibroblasts increase melanoma cell aggressiveness through increased secretion of IGFBP2, stressing the importance of considering age when designing studies and treatment. | Make paid
Hutchinson-Gilford progeria syndrome (HGPS) is a rare and fatal genetic condition arising from a single nucleotide alteration in the LMNA gene, which leads to the production of a defective lamin A protein known as progerin. The buildup of progerin hastens the onset of premature and expedited aging. Patients with HGPS exhibit short stature, low body weight, lipodystrophy, metabolic dysfunction, and skin and musculoskeletal abnormalities and, in most cases, die of cardiovascular disease by their early teenage years. Currently, no effective cure or treatment for the disease highlights the importance of discovering new therapeutic strategies. Herein, we present evidence that the hormone ghrelin, besides promoting autophagy and progerin clearance, rescued several cellular hallmarks of premature aging of human HGPS fibroblasts. Using an HGPS mouse model, LmnaG609G/G609G mice, we also show that ghrelin administration rescued the short-lived mice molecular and histopathological progeroid features, prevented progressive weight loss at later stages, reverted the lipodystrophic phenotype, and extended lifespan. Thus, we disclose that modulation of ghrelin signaling may give rise to new treatment targets and translational approaches that may improve outcomes and the health quality of HGPS patients and natural aging pathologies. | Make paid
BACKGROUND: We examined the role of pannexins in human endothelial progenitor cell (EPC) senescence. METHODS: Young and replication-induced senescent endothelial colony-forming cells (ECFCs) derived from human circulating EPCs were used to examine cellular activities and senescence-associated indicators after transfection of siRNA specific to Panx1 or lentivirus-mediated Panx1 overexpression. Hindlimb ischemia mice were used as in vivo angiogenesis model. Protein and phospho-kinase arrays were used to determine underlying mechanisms. RESULTS: Panx1 was the predominant pannexin isoform in human ECFCs and up-regulated in both replication-induced senescent ECFCs and circulating EPCs from aged mice and humans. Cellular activities of the young ECFCs were enhanced by Panx1 down-regulation, but attenuated by its up-regulation. In addition, reduction of Panx1 in the senescent ECFCs could rejuvenate cellular activities with reduced senescence-associated indicators, including senescence-associated ?-galactosidase activity, p16INK4a, p21, acetyl-p53, and phospho-Histone H2A.X. In mouse ischemic hindlimbs injected senescent ECFCs, blood perfusion ratio, salvaged limb outcome, and capillary density were all improved by Panx1 knockdown. Insulin-like growth factor 1 (IGF-1) was significantly increased in the supernatant from senescent ECFCs after Panx1 knockdown. The enhanced activities and paracrine effects of Panx1 knockdown senescent ECFCs were completely inhibited by anti-IGF-1 antibodies. FAK, ERK and STAT3 were activated in senescent ECFCs with Panx1 knockdown, in which the intracellular calcium level was reduced, and the activation was inhibited by supplemented calcium. The increased IGF-1 in Panx1-knockdown ECFCs was abrogated respectively by inhibitors of FAK (PF562271), ERK (U0126), and STAT3 (NSC74859), and supplemented calcium. CONCLUSIONS: Panx1 expression is up-regulated in human ECFCs/EPCs with replication-induced senescence and during aging. Angiogenic potential of senescent ECFCs is improved by Panx1 reduction through increased IGF-1 production via activation of FAK-ERK axis following calcium influx reduction. Our findings provide new strategies to evaluate EPC activities and rejuvenate senescent EPCs for therapeutic angiogenesis. | Make paid
Natural selection has shaped a wide range of lifespans across mammals, with a few long-lived species showing negligible signs of ageing. Approaches used to elucidate the genetic mechanisms underlying mammalian longevity usually involve phylogenetic selection tests on candidate genes, analyses of differential gene expression between age cohorts or species, and measuring age-related epigenetic changes. However, the link between gene duplication and evolution of mammalian longevity has not been widely investigated. Here, we explored the association between gene duplication and mammalian lifespan by analysing 287 human longevity-associated genes across 37 placental mammals. We estimated that the expansion rate of these genes is eight times higher than their contraction rate across these 37 species. Using phylogenetic approaches, we identified 43 genes whose duplication levels are significantly correlated with longevity quotients (FDR < 0.05). In particular, strong correlation observed for four genes (CREBBP, PIK3R1, HELLS, FOXM1) appears to be driven mainly by their high duplication levels in two ageing extremists, the naked mole rat (Heterocephalus glaber) and the greater mouse-eared bat (Myotis myotis). Further sequence and expression analyses suggest that the gene PIK3R1 may have undergone a convergent duplication event, whereby the similar region of its coding sequence was independently duplicated multiple times in both of these long-lived species. Collectively, this study identified several candidate genes whose duplications may underlie the extreme longevity in mammals, and highlighted the potential role of gene duplication in the evolution of mammalian long lifespans. | Make paid
Sex-specific lifespan dimorphism is observed in many species, with females often outliving males. This is thought to be due to sex-specific and unequal resource allocation between reproduction and maintenance. However, most studies on ageing focus on animals with traditional sex roles, where females have the highest energy burden with both egg production and parental care. This leaves a gap in our understanding of how resource allocation and senescence are linked in species with non-traditional roles. To address this, we investigated the relationship between sex (biological) and sex role (behavioural) on resource allocation trade-offs in somatic maintenance in the broad-nosed pipefish Syngnathus typhle. This species is sex-role reversed, with males acting as the primary caretaker for offspring through their unique male pregnancy, providing the opportunity to decouple the roles of sex and sex role in resource allocation. Our results suggest that while some gene groups are influenced by sex roles (e.g., genome maintenance and immune defence), others depend on biological sex and hormones (e.g., energy and fat storage), with differences becoming more pronounced with age. These findings challenge traditional ageing theories and improve our understanding of how sex-specific differences in ageing are shaped. | Make paid
Objective: Listening Difficulty (LiD) refers to the challenges individuals face when trying to hear and comprehend speech and other sounds. LiD can arise from various sources, such as hearing sensitivity, language comprehension, cognitive function, or auditory processing. Although some children with LiD have hearing loss, many have clinically normal audiometric thresholds. To determine the impact of hearing and cognitive factors on LiD in children with a clinically normal audiogram, we conducted a longitudinal study. The Evaluation of Children's Listening & Processing Skills (ECLiPS), a validated and standardized caregiver evaluation tool, was used to group participants as either LiD or typically developing (TD). Our previous study aimed to characterize LiD in 6- to 13-year-old children during the project's baseline, cross-sectional phase. We found that children with LiD needed a higher signal-to-noise ratio during speech-in-speech tests and scored lower on all assessed components of the NIH Cognition Toolbox than TD children. The primary goal of our current study was to examine if these differences between LiD and TD groups are temporary or enduring throughout childhood. Design: This longitudinal study had three data collection waves for children with LiD and TD aged 6-13 years at Wave 1, followed by assessments at 2-year (Wave 2) and 4-year (Wave 3) intervals. The primary analysis focused on data from Waves 1 and 2, while a secondary analysis encompassed all three waves despite high attrition at Wave 3. Caregivers completed the ECLiPS, while participants underwent the Listening in Spatialized Noise Sentences test (LiSN-S) and the NIH Toolbox Cognition Battery during each wave. The analysis consisted of: 1) examining longitudinal differences between TD and LiD groups in demographics, listening, auditory, and cognitive function; 2) identifying the functional domains contributing to LiD longitudinally; and 3) evaluating the test-retest reliability of the measures across waves. Mixed-effect models were employed to analyze longitudinal data. Results: The study enrolled 169 participants, with 147, 100, and 31 children completing the required testing during Waves 1, 2, and 3 study visits, respectively. The mean ages at these waves were 9.5, 12.0, and 14.0 years old. Children with LiD consistently underperformed TD children in auditory and cognitive tasks across all waves. Maternal education, auditory and cognitive abilities independently predicted caregiver-reported listening skills. The measures exhibited significant correlations between Waves 1 and 2, displaying high reliability. Longitudinal analysis of Wave 3 participants corresponded with the primary analyses of Waves 1 and 2, reinforcing the enduring nature of listening difficulties. Conclusion: Children with LiD and clinically normal audiograms experience persistent auditory, listening, and cognitive challenges through at least adolescence. The degree of LiD can be independently predicted by maternal education, cognitive processing, and spatial listening skills. This study underscores the importance of early detection and intervention for childhood LiD and highlights the role of socioeconomic factors as contributors to these challenges. | Make paid
Using lineage tracing and fate mapping strategies to study vertebrate aging has lagged behind developmental studies, primarily due to of the relatively long lifespans of classical models. Here, we introduce the Killibow, an inducible transgenic model for in-vivo multicolor lineage tracing in the naturally short-lived turquoise killifish (N. furzeri). We demonstrate that Cre-mediated recombination in transgenic fish can generate robust and stochastic labeling that remains stable during aging and regeneration. In addition, to achieve inducible control of recombination, we either utilize in-vivo Cre electroporation or use the tamoxifen system in Killibow-derived cells. To further enable transplantation assays, we establish the first immunocompromised killifish model by mutating rag2. RNA sequencing reveals that rag2 mutants exhibit severely compromised expression of V(D)J recombination products, including immunoglobulins. Accordingly, we demonstrate that clearance of transplanted Killibow-derived cells is delayed in rag2 recipients, and present a proof-of-principle for a KRASG12D cancer model that is compatible with lineage tracing. Our platform provides the opportunity to examine tissue homeostasis, stem cell function, cancer dynamics, and tissue regeneration at unprecedented temporal resolution during vertebrate aging and disease. | Make paid
In prion diseases, the cellular prion protein PrPC is converted into aggregates of PrPSc, leading to pro-found neurotoxicity through largely unknown mechanisms. Here we report that the cellular prion protein PrPC acts as an antagonist of the adhesion G protein-coupled receptor (GPCR) Adgrd1. When overexpressed in cultured cells, Adgrd1 recruited the G-protein Gs, inducing excessive cytosolic cAMP, growth arrest and cytotoxicity, all of which were suppressed by FT25-50, a 26-meric peptide from the N-terminal flexible tail (FT) of PrPC. We found that FT25-50 forms a complex with Adgrd1 and suppresses its intrinsic activation by the Stachel peptide. Adgrd1 ablation attenuated the neurodegeneration of prion-infected cerebellar organotypic slice cultures and prolonged the healthspan of prion-infected mice. Interaction studies with mutated proteins, computational modeling and docking studies revealed that suppression of Adgrd1 signaling requires the polybasic domain of the FT and the N-terminal fragment of Adgrd1. In the absence of PrPC, the cAMP spike caused by Adgrd1 was suppressed by co-expression of a functionally dead Adgrd1-Adgrg6 chimeric receptor, suggesting that Adgrd1 activation requires an unidentified agonistic ligand displaced by FT25-50. These results identify Adgrd1 as a mediator of prion toxicity and suggest that Adgrd1 modulators may be beneficial against prion-related neurodegeneration. | Make paid
Aging of the vasculature is associated with detrimental changes in vascular smooth muscle cell (VSMC) mechanosensitivity to extrinsic forces in their surrounding microenvironment. However, how chronological aging alters VSMCs ability to sense and adapt to mechanical perturbations remains unexplored. Here, we show defective VSMC mechanosensation in aging measured with ultrasound tweezers-based micromechanical system, force instantaneous frequency spectrum and transcriptome analyses. The mechanobiological study reveals that aged VSMCs adapt a relatively inert solid-like state with altered actin cytoskeletal integrity, resulting in an impairment in their mechanosensitivity and dynamic mechanoresponse to mechanical perturbations. The aging-associated decline in mechanosensation behaviors is mediated by hyperactivity of Piezo1-dependent calcium signaling. Inhibition of Piezo1 alleviates vascular aging and partially restores the loss in dynamic contractile properties in aged cells. Altogether, our study reveals the novel signaling pathway underlying aging-associated aberrant mechanosensation in VSMC and identifies Piezo1 as a potential therapeutic mechanobiological target to alleviate vascular aging. | Make paid
Variations of cell-type proportions within tissues could be informative of biological aging and disease risk. Single-cell RNA-sequencing offers the opportunity to detect such differential abundance (DA) patterns, yet this task can be statistically challenging due to the noise in single-cell data, inter-sample variability and because DA patterns are often of small effect size. Here we present a DA-testing paradigm called ELVAR that uses cell attribute aware clustering when inferring differentially enriched communities within the single-cell manifold. Using simulated and real single-cell and single-nucleus RNA-Seq datasets, we benchmark ELVAR against an analogous DA algorithm that uses Louvain for clustering, as well as local neighborhood-based DA-testing methods, demonstrating that ELVAR improves the sensitivity to detect DA-shifts in relation to aging, precancerous states and Covid-19 phenotypes. In effect, leveraging cell attribute information when inferring cell communities can denoise single-cell data, avoid the need for batch correction and help retrieve more robust cell states for subsequent DA-testing. ELVAR is available as an open-source R-package. | Make paid
Purpose: There is no established clinical standard to evaluate ankle proprioception in children with cerebral palsy (CP). This study compared ankle position sense of children with CP to age-matched children typically developing (TD). Methods: Children aged 6-17 years participated (15 CP, 58 TD). Using a custom-built device, the ankle was passively rotated to 2 positions for 25 trials. Using a psychophysical forced-choice paradigm, participants indicated which position was more plantarflexed. A psychometric function was fitted to the response data to determine the just noticeable difference (JND) threshold and the associated uncertainty (random error) for ankle position sense. Results: Median JND thresholds for the CP group were elevated (CP: 4.3{degrees}, TD: 3.0{degrees}). Three children with CP exceeded the 95th percentile of TD. No differences in random error were found. Conclusion: This method assessed ankle proprioception relative to norm data and identified position sense impairments in children with CP. Using this method can provide data on proprioceptive status in CP, augmenting the assessment of motor impairment. | Make paid
As populations age globally, cooperation across multi-sector stakeholders is increasingly important to service older persons, particularly those with high and complex health and social needs. One such population is older people entering society after a period of incarceration in prison. The ageing epidemic in prisons worldwide has caught the attention of researchers, governments and community organisations, who identify challenges in servicing this group as they re-enter the community. Challenges lie across multiple sectors, with inadequate support leading to dire consequences for public health, social welfare and recidivism. This is the first study to bring together multi-sector stakeholders from Australia to form recommendations for improving health and social outcomes for older people re-entering community after imprisonment. A modified nominal group technique was used to produce recommendations from N=15 key stakeholders across prison health, corrections, research, advocacy, aged care, community services, via online workshops. The importance and priority of these recommendations was validated by a broader sample of N=44 stakeholders, using an online survey. Thirty-six recommendations for improving outcomes for this population were strongly supported. These recommendations entail two important findings about this population: (1) They are a high-needs, unique, and underserved group at risk of significant health and social inequity in the community, (2) Multi-sector stakeholder cooperation will be crucial to service this growing group. | Make paid
Pathogenic mitochondrial (mt)DNA single nucleotide variants are the most common cause of adult mitochondrial disease. Whilst levels of the most common heteroplasmic variant (m.3243A>G) remain stable in post-mitotic tissues, levels in mitotic tissues, such as blood, decrease with age. Given differing division rates, longevity and energetic requirements within haematopoietic lineages, we hypothesised that variant level decline is driven by cell-type specific mitochondrial metabolic requirements. To address this, we coupled cell sorting with mtDNA sequencing to investigate mtDNA variant levels within progenitor, myeloid and lymphoid lineages from 26 individuals harbouring pathogenic mtDNA variants. We report that whilst the level of m.3243A>G declines with age in all analysed cell types, the T-cell lineage shows a significantly greater decline. This was confirmed for a second pathogenic tRNA variant; m.8344A>G, indicating that this phenomenon is not limited to m.3243A>G. High-throughput single cell analysis revealed that decline is driven by increasing proportions of cells that have cleared the variant genome, following a hierarchy that follows the current orthodoxy of T-cell differentiation and maturation. This work identifies the unique ability of T-cell subtypes to selectively purify their mitochondrial genomes, and identifies pathogenic mtDNA variants as a new means to track blood cell differentiation status. | Make paid
Overweight and obesity are associated with increased rates of chronic disease and death globally. In Cambodia, the prevalence of overweight and obesity among women of reproductive age (WRA) is high and increasing. This study aimed to determine the prevalence and examined sociodemographic and behavioral factors associated with overweight and/or obesity among women of reproductive age (WRA) in Cambodia. We analyzed data from the 2021-2022 Cambodia Demographic and Health Survey (CDHS) that used a two-stage stratified cluster sampling design. Data analysis was restricted to non-pregnant women, resulting in an analytic sample of 9,417 WRA. Multivariable logistic regressions were performed using STATA V17 to examine factors associated with overweight and obesity. Prevalence of overweight and obesity among non-pregnant women of reproductive age were 22,56% and 5.61% were overweight and obese respectively. Factors independently associated with increased odds of overweight and/or obesity including women aged 20-29 years [AOR=1.85; 95% CI: 1.22 - 2.80], 30-39 years [AOR=3.34; 95% CI: 2.21 - 5.04] and 40-49 years [AOR=5.57; 95% CI: 3.76 - 8.25] married [AOR=2.49; 95% CI: 1.71 - 3.62], middle wealth quintile [AOR=1.21; 95% CI : 1.02 - 1.44], and rich wealth quintile [AOR=1.44 ; 95% CI: 1.19 - 1.73], having at least three children or more [AOR=1.40; 95% CI: 1.00 - 1.95], ever drink alcohol [AOR=1.24 ; 95% CI: 1.04 - 1.47], and current drink alcohol [AOR=1.2; 95% CI: 1.01 - 1.45]. On the contrary, the following factors were independently associated with decreased odds of having overweight and obese: women with at least secondary education [AOR=0.73; 95% CI: 0.58-0.91], working in in manual labor jobs [AOR=0.76; 95% CI: (0.64 - 0.90]. Increased age, married women, having at least three children and alcohol consumption were the main risk factors associated with overweight and/or obesity. Conversely, higher education, and working in manual labor were negatively associated with overweight and/or obesity. Cambodia non-communicable disease (NCD) public health programs should consider this characteristic for targeting interventions to further reduce overweight and/or obesity in the coming year | Make paid
This study examined the spatial distribution and social inequalities in COVID-19 vaccine coverage among children aged 5-11 in Brazil. First and second dose vaccine coverage was calculated for all Brazilian municipalities and analyzed by geographic region and deciles based on human development index (HDI-M) and expected years of schooling at 18 years of age. Multilevel models were used to determine the variance partition coefficient, and bivariate local Moran's I statistic was used to assess spatial association. Results showed significant differences in vaccine coverage rates among Brazilian municipalities, with lower coverage in the North and Midwest regions. Municipalities with lower HDI and expected years of schooling had consistently lower vaccine coverage rates. Bivariate clustering analysis identified extensive concentrations of municipalities in the Northern and Northeastern regions with low vaccine coverage and low human development, while some clusters of municipalities in the Southeast and South regions with low coverage were located in areas with high HDI-M. These findings highlight the persistent municipal-level inequalities in vaccine coverage among children in Brazil and the need for targeted interventions to improve vaccine access and coverage in underserved areas. | Make paid
In 2013, the ALFA (ALzheimer and FAmilies) project was established to investigate pathophysiological changes in preclinical Alzheimer's disease (AD), and to foster research on early detection and preventive interventions. Since then, it has prospectively followed cognitively unimpaired late/middle-aged participants, most of whom are adult children of AD patients. Risk stratification of cognitively unimpaired individuals, including genetic factors is key for implementing AD prevention strategies. Here, we report the genetic characterization of ALFA participants with respect to neurodegenerative/cerebrovascular diseases, AD biomarkers, brain endophenotypes, risk factors and aging biomarkers, emphasizing amyloid/tau status and gender differences. We additionally compared AD risk in ALFA to that across the full disease spectrum from the Alzheimer's Disease Neuroimaging Initiative (ADNI). Results show that the ALFA project has been successful at establishing a cohort of cognitively unimpaired individuals at high genetic risk of AD. It is, therefore, well-suited to study early pathophysiological changes in the preclinical AD continuum. | Make paid
The Fontan circulation predisposes to multiple morbidities typically associated with older age but occurring in their third and fourth decades, consistent with premature aging. In this pilot study, we evaluated whether the Fontan circulation is associated with premature epigenetic aging. We found that in whole blood, delta-age, the difference between chronological age and estimated epigenetic DNAge, was significantly higher in those living with a Fontan circulation than in a reference cohort (z=5.59, p<0.0001), with a mean delta-age in adults post-Fontan of +4.9 years (95% CI 3.3-6.5, p<0.0001). Our results suggest that the Fontan circulation is associated with accelerated epigenetic aging, mirroring the premature aging clinical phenotype. In a life-limiting condition with few treatment options, targeting epigenetic aging may represent a novel opportunity for intervention. | Make paid