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1.
Theor Popul Biol ; 2024 Jul 15.
Article in English | MEDLINE | ID: mdl-39019333

ABSTRACT

Multi-type birth-death processes underlie approaches for inferring evolutionary dynamics from phylogenetic trees across biological scales, ranging from deep-time species macroevolution to rapid viral evolution and somatic cellular proliferation. A limitation of current phylogenetic birth-death models is that they require restrictive linearity assumptions that yield tractable message-passing likelihoods, but that also preclude interactions between individuals. Many fundamental evolutionary processes-such as environmental carrying capacity or frequency-dependent selection-entail interactions, and may strongly influence the dynamics in some systems. Here, we introduce a multi-type birth-death process in mean-field interaction with an ensemble of replicas of the focal process. We prove that, under quite general conditions, the ensemble's stochastically evolving interaction field converges to a deterministic trajectory in the limit of an infinite ensemble. In this limit, the replicas effectively decouple, and self-consistent interactions appear as nonlinearities in the infinitesimal generator of the focal process. We investigate a special case that is rich enough to model both carrying capacity and frequency-dependent selection while yielding tractable message-passing likelihoods in the context of a phylogenetic birth-death model.

2.
Adv Sci (Weinh) ; : e2403366, 2024 Jul 02.
Article in English | MEDLINE | ID: mdl-38953394

ABSTRACT

Bubbles and foams are often removed via chemical defoamers and/or mechanical agitation. Designing surfaces that promote chemical-free and energy-passive bubble capture is desirable for numerous industrial processes, including mineral flotation, wastewater treatment, and electrolysis. When immersed, super-liquid-repellent surfaces form plastrons, which are textured solid topographies with interconnected gas domains. Plastrons exhibit the remarkable ability of capturing bubbles through coalescence. However, the two-step mechanics of plastron-induced bubble coalescence, namely, rupture (initiation and location) and subsequent absorption (propagation and drainage) are not well understood. Here, the influence of 1) topographical feature size and 2) gas fraction on bubble capture dynamics is investigated. Smaller feature sizes accelerate rupture while larger gas fractions markedly improve absorption. Rupture is initiated solely on solid domains and is more probable near the edges of solid features. Yet, rupture time becomes longer as solid fraction increases. This counterintuitive behavior represents unexpected complexities. Upon rupture, the bubble's moving liquid-solid contact line influences its absorption rate and equilibrium state. These findings show the importance of rationally minimizing surface feature sizes and contact line interactions for rapid bubble rupture and absorption. This work provides key design principles for plastron-induced bubble coalescence, inspiring future development of industrially-relevant surfaces for underwater bubble capture.

3.
Space Sci Rev ; 220(5): 51, 2024.
Article in English | MEDLINE | ID: mdl-38948073

ABSTRACT

The Radar for Europa Assessment and Sounding: Ocean to Near-surface (REASON) is a dual-frequency ice-penetrating radar (9 and 60 MHz) onboard the Europa Clipper mission. REASON is designed to probe Europa from exosphere to subsurface ocean, contributing the third dimension to observations of this enigmatic world. The hypotheses REASON will test are that (1) the ice shell of Europa hosts liquid water, (2) the ice shell overlies an ocean and is subject to tidal flexing, and (3) the exosphere, near-surface, ice shell, and ocean participate in material exchange essential to the habitability of this moon. REASON will investigate processes governing this material exchange by characterizing the distribution of putative non-ice material (e.g., brines, salts) in the subsurface, searching for an ice-ocean interface, characterizing the ice shell's global structure, and constraining the amplitude of Europa's radial tidal deformations. REASON will accomplish these science objectives using a combination of radar measurement techniques including altimetry, reflectometry, sounding, interferometry, plasma characterization, and ranging. Building on a rich heritage from Earth, the moon, and Mars, REASON will be the first ice-penetrating radar to explore the outer solar system. Because these radars are untested for the icy worlds in the outer solar system, a novel approach to measurement quality assessment was developed to represent uncertainties in key properties of Europa that affect REASON performance and ensure robustness across a range of plausible parameters suggested for the icy moon. REASON will shed light on a never-before-seen dimension of Europa and - in concert with other instruments on Europa Clipper - help to investigate whether Europa is a habitable world.

4.
Prenat Diagn ; 2024 Jul 09.
Article in English | MEDLINE | ID: mdl-38982329

ABSTRACT

OBJECTIVE: The objective of this study was to evaluate whether patient-level neighborhood deprivation index (NDI) was associated with termination of pregnancy consideration and completion in patients presenting with fetal myelomeningocele. METHODS: This was a retrospective cohort analysis of patients with fetal myelomeningocele presenting to a fetal treatment center (FTC) in Illinois between 2018 and 2024. The exposure was NDI calculated from patient zip codes. The NDI was analyzed as both a dichotomous and ordinal exposure. The co-primary outcomes were abortion consideration prior to FTC consultation, ascertained by nurse intake, and abortion completion after consultation. Bivariate and log-binomial regression analyses were performed. Covariates were selected based on p < 0.10 on bivariate analyses. Otherwise, p < 0.05 indicated statistical significance. RESULTS: A total of 157 participants were included. Evaluation of neighborhood deprivation as a dichotomous exposure revealed no association with abortion consideration or completion. AdditionallLy, no association was found on log binomial modeling after controlling for gestational age at presentation to the FTC and maternal race or ethnicity for abortion consideration (aRR 0.87, 95% CI 0.59-1.28) or completion (aRR 0.86, 95% CI 0.59-1.28). These results were similar when treating the NDI as an ordinal exposure. CONCLUSIONS: Contrary to our hypothesis, NDI is not associated with abortion consideration or completion in patients with fetal myelomeningocele.

5.
Circulation ; 2024 Jul 11.
Article in English | MEDLINE | ID: mdl-38989575

ABSTRACT

BACKGROUND: Fenestrated-branched endovascular aortic repair (FB-EVAR) has been used as a minimally invasive alternative to open surgical repair to treat patients with thoracoabdominal aortic aneurysms (TAAAs). The aim of this study was to evaluate aortic-related mortality (ARM) and aortic aneurysm rupture after FB-EVAR of TAAAs. METHODS: Patients enrolled in 8 prospective, nonrandomized, physician-sponsored investigational device exemption studies between 2005 and 2020 who underwent elective FB-EVAR of asymptomatic intact TAAAs were analyzed. Primary end points were ARM, defined as any early mortality (30 days or in hospital) or late mortality from aortic rupture, dissection, organ or limb malperfusion attributable to aortic disease, complications of reinterventions, or aortic rupture. Secondary end points were early major adverse events, TAAA life-altering events (defined as death, permanent spinal cord injury, permanent dialysis, or stroke), all-cause mortality, and secondary interventions. RESULTS: A total of 1109 patients were analyzed; 589 (53.1%) had extent I-III and 520 (46.9%) had extent IV TAAAs. Median age was 73.4 years (interquartile range, 68.1-78.3 years); 368 (33.2%) were women. Early mortality was 2.7% (n=30); congestive heart failure was associated with early mortality (odds ratio, 3.30 [95% CI, 1.22-8.02]; P=0.01). Incidence of early aortic rupture was 0.4% (n=4). Incidence of early major adverse events and TAAA life-altering events was 20.4% (n=226) and 7.7% (n=85), respectively. There were 30 late ARMs; 5-year cumulative incidence was 3.8% (95% CI, 2.6%-5.4%); older age and extent I-III TAAAs were independently associated with late ARM (each P<0.05). Fourteen late aortic ruptures occurred; 5-year cumulative incidence was 2.7% (95% CI, 1.2%-4.3%); extent I-III TAAAs were associated with late aortic rupture (hazard ratio, 5.85 [95% CI, 1.31-26.2]; P=0.02). Five-year all-cause mortality was 45.7% (95% CI, 41.7%-49.4%). Five-year cumulative incidence of secondary intervention was 40.3% (95% CI, 35.8%-44.5%). CONCLUSIONS: ARM and aortic rupture are uncommon after elective FB-EVAR of asymptomatic intact TAAAs. Half of the ARMs occurred early, and most of the late deaths were not aortic related. Late all-cause mortality rate and the need for secondary interventions were 46% and 40%, respectively, 5 years after FB-EVAR. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifiers: NCT02089607, NCT02050113, NCT02266719, NCT02323581, NCT00583817, NCT01654133, NCT00483249, NCT02043691, and NCT01874197.

6.
Br J Clin Pharmacol ; 2024 Jul 12.
Article in English | MEDLINE | ID: mdl-38994750

ABSTRACT

AIMS: Tacrolimus, metabolized by CYP3A4 and CYP3A5 enzymes, is susceptible to drug-drug interactions (DDI). Steroids induce CYP3A genes to increase tacrolimus clearance, but the effect is variable. We hypothesized that the extent of the steroid-tacrolimus DDI differs by CYP3A4/5 genotypes. METHODS: Kidney transplant recipients (n = 2462) were classified by the number of loss of function alleles (LOF) (CYP3A5*3, *6 and *7 and CYP3A4*22) and steroid use at each tacrolimus trough in the first 6 months post-transplant. A population pharmacokinetic analysis was performed by nonlinear mixed-effect modelling (NONMEM) and stepwise covariate modelling to define significant covariates affecting tacrolimus clearance. A stochastic simulation was performed and translated into a Shiny application with the mrgsolve and Shiny packages in R. RESULTS: Steroids were associated with modestly higher (3%-11.8%) tacrolimus clearance. Patients with 0-LOF alleles receiving steroids showed the greatest increase (11.8%) in clearance compared to no steroids, whereas those with 2-LOFs had a negligible increase (2.6%) in the presence of steroids. Steroid use increased tacrolimus clearance by 5% and 10.3% in patients with 1-LOF and 3/4-LOFs, respectively. CONCLUSIONS: Steroids increase the clearance of tacrolimus but vary slightly by CYP3A genotype. This is important in individuals of African ancestry who are more likely to carry no LOF alleles, may more commonly receive steroid treatment, and will need higher tacrolimus doses.

7.
Animals (Basel) ; 14(13)2024 Jun 27.
Article in English | MEDLINE | ID: mdl-38998011

ABSTRACT

The confinement of transgenic fish is essential to prevent their escape and reproduction in natural ecosystems. Reversible transgenic sterilization is a promising approach to control the reproduction of transgenic fish. Therefore, the present study was conducted to develop a reversibly sterile channel catfish (Ictalurus punctatus) via the transgenic overexpression of the goldfish (Carassius auratus) glutamic acid decarboxylase (GAD) gene driven by the common carp (Cyprinus carpio) ß-actin promoter to disrupt normal gamma-aminobutyric acid (GABA) regulation. Three generations of GAD-transgenic fish were produced. All studied generations showed repressed reproductive performance; however, this was not always statistically significant. In F1, 5.4% of the transgenic fish showed a sexual maturity score ≥ 4 (maximum = 5) at five years of age, which was lower (p = 0.07) than that of the control group (16.8%). In the spawning experiments conducted on F1 transgenic fish at six and nine years of age, 45.5% and 20.0% of fish spawned naturally, representing lower values (p = 0.09 and 0.12, respectively) than the percentages in the sibling control fish of the same age (83.3% and 66.7%, respectively). Four of six pairs of the putative infertile six-year-old fish spawned successfully after luteinizing hormone-releasing hormone analog (LHRHa) therapy. Similar outcomes were noted in the three-year-old F2 fish, with a lower spawning percentage in transgenic fish (20.0%) than in the control (66.7%). In one-year-old F2-generation transgenic fish, the observed mean serum gonadotropin-releasing hormone (GnRH) levels were 9.23 ± 2.49 and 8.14 ± 2.21 ng/mL for the females and males, respectively. In the control fish, the mean levels of GnRH were 11.04 ± 4.06 and 9.03 ± 2.36 ng/mL for the females and males, respectively, which did not differ significantly from the control (p = 0.15 and 0.27 for females and males, respectively). There was no significant difference in the estradiol levels of the female transgenic and non-transgenic fish in the one- and four-year-old F2-generation fish. The four-year-old F2-generation male transgenic fish exhibited significantly (p < 0.05) lower levels of GnRH and testosterone than the control fish. In conclusion, while overexpressing GAD repressed the reproductive abilities of channel catfish, it did not completely sterilize transgenic fish. The sterilization rate might be improved through selection in future generations.

8.
Am J Trop Med Hyg ; 2024 Jul 16.
Article in English | MEDLINE | ID: mdl-39013372

ABSTRACT

Flea-borne spotted fever and flea-borne (murine) typhus are rickettsioses caused by Rickettsia felis and Rickettsia typhi, respectively, and typically present as undifferentiated febrile illnesses. The relative contribution of these agents to flea-borne rickettsioses in California is unclear. We have developed a duplex reverse transcription real-time polymerase chain reaction (RT-rtPCR) assay targeting R. felis- and R. typhi-specific 23S ribosomal RNA single nucleotide polymorphisms to better understand the respective roles of these agents in causing flea-borne rickettsioses in California. This assay was compared with an established duplex R. felis- and R. typhi-ompB rt-PCR assay and was shown to have 1,000-fold and 10-fold greater analytical sensitivity for the detection of R. felis and R. typhi, respectively. Retrospective testing of clinical specimens with both assays established R. typhi as the major etiologic agent of flea-borne rickettsioses in California.

9.
J Occup Environ Med ; 2024 Jul 17.
Article in English | MEDLINE | ID: mdl-39016286

ABSTRACT

OBJECTIVE: Respirator medical evaluations are an important component of occupational health practice. Concepts and practices were established 25-50 years ago.METHODWe suggest analysis and discussion of three areas warranting update. RESULTS: a) Shifting from disease-based decisions to evaluating 12 specific domains- cardiopulmonary, sudden change in condition, thermal, work interference, exacerbating existing condition, donning/doffing, dermatologic, proper utilization, fit testing interference, cultural/religious, arms/legs, subjective responses. Two distinct evaluation processes are advised-"algorithmic" for the frequent straightforward evaluations and "specialist" for the more complex. b) Acknowledging the importance of subjective responses and clarifying the underlying causes - external stimulus, sensation, perception, interpretation, acceptability, and emotional response. c) Optimizing the organizational structures by explicitly defining the scope of evaluations, modifying the sequencing of assessment, and specifying qualifications of clinicians performing assessments. CONCLUSIONS: Reassessing respirator medical evaluation methods is needed.

10.
Soft Matter ; 20(27): 5273-5295, 2024 Jul 10.
Article in English | MEDLINE | ID: mdl-38952198

ABSTRACT

Silicone is frequently used as a model system to investigate and tune wetting on soft materials. Silicone is biocompatible and shows excellent thermal, chemical, and UV stability. Moreover, the mechanical properties of the surface can be easily varied by several orders of magnitude in a controlled manner. Polydimethylsiloxane (PDMS) is a popular choice for coating applications such as lubrication, self-cleaning, and drag reduction, facilitated by low surface energy. Aiming to understand the underlying interactions and forces, motivated numerous and detailed investigations of the static and dynamic wetting behavior of drops on PDMS-based surfaces. Here, we recognize the three most prevalent PDMS surface variants, namely liquid-infused (SLIPS/LIS), elastomeric, and liquid-like (SOCAL) surfaces. To understand, optimize, and tune the wetting properties of these PDMS surfaces, we review and compare their similarities and differences by discussing (i) the chemical and molecular structure, and (ii) the static and dynamic wetting behavior. We also provide (iii) an overview of methods and techniques to characterize PDMS-based surfaces and their wetting behavior. The static and dynamic wetting ridge is given particular attention, as it dominates energy dissipation, adhesion, and friction of sliding drops and influences the durability of the surfaces. We also discuss special features such as cloaking and wetting-induced phase separation. Key challenges and opportunities of these three surface variants are outlined.

11.
medRxiv ; 2024 Jun 16.
Article in English | MEDLINE | ID: mdl-38947067

ABSTRACT

Background: Inclusion body myositis (IBM) is the most prevalent muscle disease in adults for which no current treatment exists. The pathogenesis of IBM remains poorly defined. Inflammation and mitochondrial dysfunction are the most common histopathological findings. In this study, we aimed to explore the interplay between inflammation and mitochondrial dysfunction in IBM patients, highlighting sex differences. Methods: We included 38 IBM patients and 22 age- and sex-matched controls without myopathy. Bulk RNA sequencing, Meso Scale Discovery ELISA, western blotting, histochemistry and immunohistochemistry were performed on frozen muscle samples from the study participants. Results: We demonstrated activation of the NLRP3 inflammasome in IBM muscle samples, with the NLRP3 inflammasome pathway being the most upregulated. On muscle histopathology, there is increased NRLP3 immunoreactivity in both inflammatory cells and muscle fibers. Mitophagy is critical for removing damaged mitochondria and preventing the formation of a vicious cycle of mitochondrial dysfunction-NLRP3 activation. In the IBM muscle samples, we showed altered mitophagy, most significantly in males, with elevated levels of p-S65-Ubiquitin, a mitophagy marker. Furthermore, p-S65-Ubiquitin aggregates accumulated in muscle fibers that were mostly type 2 and devoid of cytochrome-c-oxidase reactivity. Type 2 muscle fibers are known to be more prone to mitochondrial dysfunction. NLRP3 RNA levels correlated with p-S65-Ubiquitin levels in both sexes but with loss of in muscle strength only in males. Finally, we identified sex-specific molecular pathways in IBM, with females having activation of pathways that could offset some of the pathomechanisms of IBM. Conclusions: NLRP3 inflammasome is activated in IBM, along with altered mitophagy particularly in males, which is of potential therapeutic significance. These findings suggest sex-specific mechanisms in IBM that warrant further investigation.

12.
Front Immunol ; 15: 1427100, 2024.
Article in English | MEDLINE | ID: mdl-38983847

ABSTRACT

Introduction: Interleukin-18 (IL-18), a pro-inflammatory cytokine belonging to the IL-1 Family, is a key mediator ofautoinflammatory diseases associated with the development of macrophage activation syndrome (MAS).High levels of IL-18 correlate with MAS and COVID-19 severity and mortality, particularly in COVID-19patients with MAS. As an inflammation inducer, IL-18 binds its receptor IL-1 Receptor 5 (IL-1R5), leadingto the recruitment of the co-receptor, IL-1 Receptor 7 (IL-1R7). This heterotrimeric complex subsequentlyinitiates downstream signaling, resulting in local and systemic inflammation. Methods: We reported earlier the development of a novel humanized monoclonal anti-human IL-1R7 antibody whichspecifically blocks the activity of human IL-18 and its inflammatory signaling in human cell and wholeblood cultures. In the current study, we further explored the strategy of blocking IL-1R7 inhyperinflammation in vivo using animal models. Results: We first identified an anti-mouse IL-1R7 antibody that significantly suppressed mouse IL-18 andlipopolysaccharide (LPS)-induced IFNg production in mouse splenocyte and peritoneal cell cultures. Whenapplied in vivo, the antibody reduced Propionibacterium acnes and LPS-induced liver injury and protectedmice from tissue and systemic hyperinflammation. Importantly, anti-IL-1R7 significantly inhibited plasma,liver cell and spleen cell IFNg production. Also, anti-IL-1R7 downregulated plasma TNFa, IL-6, IL-1b,MIP-2 production and the production of the liver enzyme ALT. In parallel, anti-IL-1R7 suppressed LPSinducedinflammatory cell infiltration in lungs and inhibited the subsequent IFNg production andinflammation in mice when assessed using an acute lung injury model. Discussion: Altogether, our data suggest that blocking IL-1R7 represents a potential therapeutic strategy to specificallymodulate IL-18-mediated hyperinflammation, warranting further investigation of its clinical application intreating IL-18-mediated diseases, including MAS and COVID-19.


Subject(s)
Inflammation , Lipopolysaccharides , Animals , Mice , Lipopolysaccharides/immunology , Inflammation/immunology , Humans , Interleukin-18/metabolism , Interleukin-18/immunology , Disease Models, Animal , COVID-19/immunology , Mice, Inbred C57BL , Macrophage Activation Syndrome/immunology , SARS-CoV-2/immunology
13.
Adv Sci (Weinh) ; : e2403028, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38946620

ABSTRACT

Superhydrophobic surfaces (SHS) exhibit a pronounced ability to resist wetting. When immersed in water, water does not penetrate between the microstructures of the SHS. Instead, a thin layer of trapped gas remains, i.e., plastron. This fractional wetting is also known as the Cassie-Baxter state (CB). Impairment of superhydrophobicity occurs when water penetrates the plastron and, when complete wetting is achieved, a Wenzel state (W) results. Subsequent recovery back to CB state is one of the main challenges in the field of SHS wetting. Current methods for plastron recovery require complex mechanical or chemical integration, are time-consuming or lack spatial control. Here an on-demand, contact-less approach for performing facile transitions between these wetting states at micrometer length scales is proposed. This is achieved by the use of acoustic radiation force (ARF) produced by high-intensity focused ultrasound (HIFU). Switching from CB to W state takes <100 µs, while the local recovery back to CB state takes <45 s. To the best of authors knowledge, this is the first demonstration of ARF-induced manipulation of the plastron enabling facile two-way controlled switching of wetting states.

14.
Trials ; 25(1): 454, 2024 Jul 04.
Article in English | MEDLINE | ID: mdl-38965624

ABSTRACT

Challenges to recruitment of family caregivers exist and are amplified when consent must occur in the context of chaotic healthcare circumstances, such as the transition from hospital to home. The onset of the COVID-19 pandemic during our randomized controlled trial provided an opportunity for a natural experiment exploring and examining different consent processes for caregiver recruitment. The purpose of this publication is to describe different recruitment processes (in-person versus virtual) and compare diversity in recruitment rates in the context of a care recipient's hospitalization. We found rates of family caregiver recruitment for in-person versus virtual were 28% and 23%, respectively (p = 0.01). Differences existed across groups with family caregivers recruited virtually being more likely to be younger, white, have greater than high school education, and not be a spouse or significant other to the care recipient, such as a child. Future work is still needed to identify the modality and timing of family caregiver recruitment to maximize rates and enhance the representativeness of the population for equitable impact.


Subject(s)
COVID-19 , Caregivers , Patient Selection , Humans , COVID-19/epidemiology , Female , Male , Middle Aged , Aged , SARS-CoV-2 , Randomized Controlled Trials as Topic , Patient Discharge
15.
Sci Adv ; 10(27): eado7576, 2024 Jul 05.
Article in English | MEDLINE | ID: mdl-38959306

ABSTRACT

Following the apparent final case in an Ebola virus disease (EVD) outbreak, the decision to declare the outbreak over must balance societal benefits of relaxing interventions against the risk of resurgence. Estimates of the end-of-outbreak probability (the probability that no future cases will occur) provide quantitative evidence that can inform the timing of an end-of-outbreak declaration. An existing modeling approach for estimating the end-of-outbreak probability requires comprehensive contact tracing data describing who infected whom to be available, but such data are often unavailable or incomplete during outbreaks. Here, we develop a Markov chain Monte Carlo-based approach that extends the previous method and does not require contact tracing data. Considering data from two EVD outbreaks in the Democratic Republic of the Congo, we find that data describing who infected whom are not required to resolve uncertainty about when to declare an outbreak over.


Subject(s)
Disease Outbreaks , Hemorrhagic Fever, Ebola , Hemorrhagic Fever, Ebola/epidemiology , Hemorrhagic Fever, Ebola/prevention & control , Democratic Republic of the Congo/epidemiology , Humans , Ebolavirus , Markov Chains , Monte Carlo Method
16.
Alzheimers Dement ; 2024 Jul 03.
Article in English | MEDLINE | ID: mdl-38958117

ABSTRACT

INTRODUCTION: Despite a two-fold risk, individuals of African ancestry have been underrepresented in Alzheimer's disease (AD) genomics efforts. METHODS: Genome-wide association studies (GWAS) of 2,903 AD cases and 6,265 controls of African ancestry. Within-dataset results were meta-analyzed, followed by functional genomics analyses. RESULTS: A novel AD-risk locus was identified in MPDZ on chromosome (chr) 9p23 (rs141610415, MAF = 0.002, P = 3.68×10-9). Two additional novel common and nine rare loci were identified with suggestive associations (P < 9×10-7). Comparison of association and linkage disequilibrium (LD) patterns between datasets with higher and lower degrees of African ancestry showed differential association patterns at chr12q23.2 (ASCL1), suggesting that this association is modulated by regional origin of local African ancestry. DISCUSSION: These analyses identified novel AD-associated loci in individuals of African ancestry and suggest that degree of African ancestry modulates some associations. Increased sample sets covering as much African genetic diversity as possible will be critical to identify additional loci and deconvolute local genetic ancestry effects. HIGHLIGHTS: Genetic ancestry significantly impacts risk of Alzheimer's Disease (AD). Although individuals of African ancestry are twice as likely to develop AD, they are vastly underrepresented in AD genomics studies. The Alzheimer's Disease Genetics Consortium has previously identified 16 common and rare genetic loci associated with AD in African American individuals. The current analyses significantly expand this effort by increasing the sample size and extending ancestral diversity by including populations from continental Africa. Single variant meta-analysis identified a novel genome-wide significant AD-risk locus in individuals of African ancestry at the MPDZ gene, and 11 additional novel loci with suggestive genome-wide significance at P < 9×10-7. Comparison of African American datasets with samples of higher degree of African ancestry demonstrated differing patterns of association and linkage disequilibrium at one of these loci, suggesting that degree and/or geographic origin of African ancestry modulates the effect at this locus. These findings illustrate the importance of increasing number and ancestral diversity of African ancestry samples in AD genomics studies to fully disentangle the genetic architecture underlying AD, and yield more effective ancestry-informed genetic screening tools and therapeutic interventions.

17.
Exp Brain Res ; 242(8): 2033-2040, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38958722

ABSTRACT

Researchers dispute the cause of errors in high Go, low No Go target detection tasks, like the Sustained Attention to Response Task (SART). Some researchers propose errors in the SART are due to perceptual decoupling, where a participant is unaware of stimulus identity. This lack of external awareness causes an erroneous response. Other researchers suggest the majority of the errors in the SART are instead due to response leniency, not perceptual decoupling. Response delays may enable a participant who is initially unaware of stimulus identity, perceptually decoupled, to become aware of stimulus identity, or perceptually recoupled. If, however, the stimulus presentation time is shortened to the minimum necessary for stimulus recognition and the stimulus is disrupted with a structured mask, then there should be no time to enable perception to recouple even with a response delay. From the perceptual decoupling perspective, there should be no impact of a response delay on performance in this case. Alternatively if response bias is critical, then even in this case a response delay may impact performance. In this study, we shortened stimulus presentation time and added a structured mask. We examined whether a response delay impacted performance in the SART and tasks where the SART's response format was reversed. We expected a response delay would only impact signal detection theory bias, c, in the SART, where response leniency is an issue. In the reverse formatted SART, since bias was not expected to be lenient, we expected no impact or minimal impact of a response delay on response bias. These predictions were verified. Response bias is more critical in understanding SART performance, than perceptual decoupling, which is rare if it occurs at all in the SART.


Subject(s)
Attention , Psychomotor Performance , Reaction Time , Humans , Attention/physiology , Female , Male , Young Adult , Adult , Reaction Time/physiology , Psychomotor Performance/physiology , Visual Perception/physiology , Adolescent , Photic Stimulation/methods
18.
Environ Health Perspect ; 132(7): 77006, 2024 Jul.
Article in English | MEDLINE | ID: mdl-39028627

ABSTRACT

BACKGROUND: Increased exposure to ambient air pollution, especially fine particulate matter ≤2.5µm (PM2.5) is associated with poorer brain health and increased risk for Alzheimer's disease (AD) and related dementias. The locus coeruleus (LC), located in the brainstem, is one of the earliest regions affected by tau pathology seen in AD. Its diffuse projections throughout the brain include afferents to olfactory areas that are hypothesized conduits of cerebral particle deposition. Additionally, extensive contact of the LC with the cerebrovascular system may present an additional route of exposure to environmental toxicants. OBJECTIVE: Our aim was to investigate if exposure to PM2.5 was associated with LC integrity in a nationwide sample of men in early old age, potentially representing one pathway through which air pollution can contribute to increased risk for AD dementia. METHODS: We examined the relationship between PM2.5 and in vivo magnetic resonance imaging (MRI) estimates of LC structural integrity indexed by contrast to noise ratio (LCCNR) in 381 men [mean age=67.3; standard deviation (SD)=2.6] from the Vietnam Era Twin Study of Aging (VETSA). Exposure to PM2.5 was taken as a 3-year average over the most recent period for which data were available (average of 5.6 years prior to the MRI scan). We focused on LCCNR in the rostral-middle portion of LC due to its stronger associations with aging and AD than the caudal LC. Associations between PM2.5 exposures and LC integrity were tested using linear mixed effects models adjusted for age, scanner, education, household income, and interval between exposure and MRI. A co-twin control analysis was also performed to investigate whether associations remained after controlling for genetic confounding and rearing environment. RESULTS: Multiple linear regressions revealed a significant association between PM2.5 and rostral-middle LCCNR (ß=-0.16; p=0.02), whereby higher exposure to PM2.5 was associated with lower LCCNR. A co-twin control analysis found that, within monozygotic pairs, individuals with higher PM2.5 exposure showed lower LCCNR (ß=-0.11; p=0.02), indicating associations were not driven by genetic or shared environmental confounds. There were no associations between PM2.5 and caudal LCCNR or hippocampal volume, suggesting a degree of specificity to the rostral-middle portion of the LC. DISCUSSION: Given previous findings that loss of LC integrity is associated with increased accumulation of AD-related amyloid and tau pathology, impacts on LC integrity may represent a potential pathway through which exposure to air pollution increases AD risk. https://doi.org/10.1289/EHP14344.


Subject(s)
Air Pollutants , Environmental Exposure , Locus Coeruleus , Magnetic Resonance Imaging , Particulate Matter , Humans , Male , Aged , Environmental Exposure/statistics & numerical data , Air Pollution/statistics & numerical data , Air Pollution/adverse effects , Aging , Middle Aged , Alzheimer Disease
19.
Ann Neurol ; 2024 Jul 19.
Article in English | MEDLINE | ID: mdl-39031103

ABSTRACT

OBJECTIVE: To evaluate the cerebrospinal fluid (CSF) cytokine/chemokine profile of central nervous system (CNS) neurosarcoidosis (NS), and its utility in differential diagnosis, treatment, and prognostication. METHODS: In this case-control study, we validated 17 cytokines/chemokines (interleukin [IL]-1-beta, IL-2, IL-4, IL-5, IL-6, IL-10, IL-12p70, IL-13, IL-17A, BAFF, IL-8/CXCL8, CXCL9, CXCL10, CXCL13, GM-CSF, interferon-gamma, and tumor necrosis factor [TNF]-alpha) in a multiplexed automated immunoassay system (ELLA; Bio-Techne, Minneapolis, MN, USA), and assessed them in CSF and serum of symptomatic patients with probable or definite CNS NS (01/2011-02/2023) with gadolinium enhancement and/or CSF pleocytosis. Patients with multiple sclerosis, primary CNS lymphoma, aquaporin-4 immunoglobulin G positivity, non-inflammatory disorders, and healthy individuals were used as controls. RESULTS: A total of 32 NS patients (59% women; median age, 59 years [19-81]) were included; concurrent sera were available in 12. CSF controls consisted of 26 multiple sclerosis, 8 primary CNS lymphoma, 84 aquaporin-4 immunoglobulin G positive, and 34 patients with non-inflammatory disorders. Gadolinium enhancement was present in 31 of 32 NS patients, and CSF pleocytosis in 27 of 32 (84%). CSF IL-2, IL-6, IL-10, IL-13, BAFF, IL-8/CXCL8, CXCL9, CXCL10, CXCL13, GM-CSF, interferon-gamma, and TNF-alpha levels were significantly higher in NS patients compared with non-inflammatory controls (p ≤ 0.02); elevations were more common in CSF than serum. Concurrent elevation of IL-6, CXCL9, CXCL10, GM-CSF, interferon-gamma, and TNF-alpha was present in 18 of 32 NS patients, but only in 1 control. Elevated IL-6, IL-10, IL-13, CXCL9, CXL10, GM-CSF, and TNF-alpha associated with measures of disease activity. INTERPRETATION: NS CSF cytokine/chemokine profiles suggest T cell (mainly T helper cell type 1), macrophage, and B-cell involvement. These signatures aid in NS diagnosis, indicate disease activity, and suggest therapeutic avenues. ANN NEUROL 2024.

20.
Schizophr Res ; 271: 129-137, 2024 Jul 17.
Article in English | MEDLINE | ID: mdl-39024961

ABSTRACT

The prodromal phase of schizophrenia provides an optimal opportunity to mitigate the profound functional disability that is often associated with fully expressed psychosis. Considerable evidence supports the importance of neurocognition in the development of interpersonal (social) and academic (role) skills. Further findings from adolescents and young adults at clinical high risk for developing psychosis (CHRP) suggest that treatment for functioning might be most effective when targeting early and specific neurocognitive deficits. The current study addresses this critical intervention issue by examining the potential of neurocognitive deficits at intake for predicting social and role functioning over time in CHR-P youth. The study included 345 CHR-P participants from the second phase of the North American Prodrome Longitudinal Study (NAPLS2) with baseline neurocognition and 2-year follow-up data on social and role functioning. Slower baseline processing speed consistently predicted poor social functioning over time, while attention deficits predicted poor role functioning at baseline and follow-up. In addition, the impact of processing speed and attention impairments on social and role functioning, respectively, persisted even when adjusting the regression models for attenuated positive, negative, and disorganized symptoms, and transition status. The current study demonstrates for, arguably the first time, that processing speed and attention are strongly predictive of social and role functioning over time, respectively, above and beyond the impact of symptoms and those CHR-P individuals that develop psychosis over the course of the study. These findings imply that early neurocognition is a critical treatment target linked to the developmental trajectory of social and role functioning.

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