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Over the past few decades, neuroimaging has become a ubiquitous tool in basic research and clinical studies of the human brain. However, no reference standards currently exist to quantify individual differences in neuroimaging metrics over time, in contrast to growth charts for anthropometric traits such as height and weight1. Here we assemble an interactive open resource to benchmark brain morphology derived from any current or future sample of MRI data ( http://www.brainchart.io/ ). With the goal of basing these reference charts on the largest and most inclusive dataset available, acknowledging limitations due to known biases of MRI studies relative to the diversity of the global population, we aggregated 123,984 MRI scans, across more than 100 primary studies, from 101,457 human participants between 115 days post-conception to 100 years of age. MRI metrics were quantified by centile scores, relative to non-linear trajectories2 of brain structural changes, and rates of change, over the lifespan. Brain charts identified previously unreported neurodevelopmental milestones3, showed high stability of individuals across longitudinal assessments, and demonstrated robustness to technical and methodological differences between primary studies. Centile scores showed increased heritability compared with non-centiled MRI phenotypes, and provided a standardized measure of atypical brain structure that revealed patterns of neuroanatomical variation across neurological and psychiatric disorders. In summary, brain charts are an essential step towards robust quantification of individual variation benchmarked to normative trajectories in multiple, commonly used neuroimaging phenotypes.

While many studies have reported that individual differences in personality traits are genetically influenced, the neurobiological bases mediating these influences have not yet been well characterized. To advance understanding concerning the pathway from genetic variation to personality, here we examined whether measures of heritable variation in neuroanatomical size in candidate regions (amygdala and medial orbitofrontal cortex) were associated with heritable effects on personality. A sample of 486 middle-aged (mean=55 years) male twins (complete MZ pairs=120; complete DZ pairs=84) underwent structural brain scans and also completed measures of two core domains of personality: positive and negative emotionality. After adjusting for estimated intracranial volume, significant phenotypic (r(p)) and genetic (r(g)) correlations were observed between left amygdala volume and positive emotionality (r(p)=.16, p

Self-esteem and well-being are important for successful aging, and some evidence suggests that self-esteem and well-being are associated with hippocampal volume, cognition and stress responsivity. Whereas most of this evidence is based on studies on older adults, we investigated self-esteem, well-being and hippocampal volume in 474 male middle-aged twins. Self-esteem was significantly positively correlated with hippocampal volume (0.09, P = 0.03 for left hippocampus, 0.10, P = 0.04 for right). Correlations for well-being were not significant (Ps > 0.05). There were strong phenotypic correlations between self-esteem and well-being (0.72, P < 0.001) and between left and right hippocampal volume (0.72, P < 0.001). In multivariate genetic analyses, a two-factor additive genetic and unique environmental (AE) model with well-being and self-esteem on one factor and left and right hippocampal volumes on the other factor fits the data better than Cholesky, independent pathway or common pathway models. The correlation between the two genetic factors was 0.12 (P = 0.03); the correlation between the environmental factors was 0.09 (P > 0.05). Our results indicate that largely different genetic and environmental factors underlie self-esteem and well-being on one hand and hippocampal volume on the other.

The presence of an ApoE ε4 allele (ε4+) increases the risk of developing Alzheimer's disease (AD). Previous studies support an adverse relationship between ε4+ status and brain structure and function in mild cognitive impairment and AD; in contrast, the presence of an ε2 allele may be protective. Whether these findings reflect disease-related effects or pre-existing endophenotypes, however, remains unclear. The present study examined the influence of ApoE allele status on brain structure solely during middle-age in a large, national sample. Participants were 482 men, ages 51-59, from the Vietnam Era Twin Study of Aging (VETSA). T1-weighted images were used in volumetric segmentation and cortical surface reconstruction methods to measure regional volume and thickness. Primary linear mixed effects models predicted structural measures with ApoE status (ε3/3, ε2/3, ε3/4) and control variables for effects of site, non-independence of twin data, age, and average cranial vault or cortical thickness. Relative to the ε3/3 group, the ε3/4 group demonstrated significantly thinner cortex in superior frontal and left rostral and right caudal midfrontal regions; there were no significant effects of ε4 status on any temporal lobe measures. The ε2/3 group demonstrated significantly thicker right parahippocampal cortex relative to the ε3/3 group. The ApoE ε4 allele may influence cortical thickness in frontal areas, which are later developing regions thought to be more susceptible to the natural aging process. Previous conflicting findings for mesial temporal regions may be driven by the inclusion of older individuals, who may evidence preclinical manifestations of disease, and by unexamined moderators of ε4-related effects. The presence of the ε2 allele was related to thicker cortex, supporting a protective role. Ongoing follow-up of the VETSA sample may shed light on the potential for age-and disease-related mediation of the influence of ApoE allele status. © 2011 The authors and IOS Press. All rights reserved.

Background: Atherosclerosis forms the pathological basis for the development of cardiovascular disease. Since pathological processes initially develop without clinically relevant symptoms, the identification of early markers in the subclinical stage plays an important role for initiating early interventions. There is evidence that regulatory T cells (Tregs) are involved in the development of atherosclerosis. Therefore, the present study aimed to identify and investigate associations with Tregs and their subsets in a cohort of healthy elderly individuals with and without subclinical atherosclerotic plaques (SAP). In addition, various lifestyle and risk factors, such as cardiorespiratory fitness, were investigated as associated signatures. Methods: A cross-sectional study was performed in 79 participants (male: n = 50; age = 63.6 ± 3.7 years; body mass index = 24.9 ± 3.1 kg/m²; mean ± SD) who had no previous diagnosis of chronic disease and were not taking medication. Ultrasound of the carotids to identify SAP, cardiovascular function measurement for vascular assessment and a cardiorespiratory fitness test to determine peak oxygen uptake were performed. Additionally, tests were conducted to assess blood lipids and determine glucose levels. Immunophenotyping of Tregs and their subtypes (resting (rTregs) and effector/memory (mTregs)) was performed by 8-chanel flow cytometry. Participants were categorized according to atherosclerotic plaque status. Linear and logistic regression models were used to analyze associations between parameters. Results: SAP was detected in a total of 29 participants. The participants with plaque were older (64.8 ± 3.6 years vs. 62.9 ± 3.5 years) and had higher peripheral systolic blood pressure (133.8 ± 14.7 mmHg vs. 125.8 ± 10.9 mmHg). The participants with SAP were characterized by a lower percentage of rTregs (28.8% ± 10.7% vs. 34.6% ± 10.7%) and a higher percentage of mTregs (40.3% ± 14.7% vs. 30.0% ± 11.9%). Multiple logistic regression identified age (odds ratio (OR) = 1.20 (95% confidence interval (95%CI): 1.01–1.42)) and mTregs (OR = 1.05 (95%CI: 1.02–1.10)) as independent risk factors for SAP. Stepwise linear regression could reveal an association of peak oxygen uptake (β = 0.441), low-density lipoprotein (LDL) (β = –0.096), and SAP (β = 6.733) with mTregs and LDL (β = 0.104) with rTregs. Conclusion: While at an early stage of SAP, the total proportion of Tregs gives no indication of vascular changes, this is indicated by a shift in the Treg subgroups. Factors such as serum LDL or cardiopulmonary fitness may be associated with this shift and may also be additional diagnostic indicators. This could be used to initiate lifestyle-based preventive measures at an early stage, which may have a protective effect against disease progression.

Abstract Respiratory virus infections play a major role in asthma, while there is a close correlation between asthma and food allergy. We hypothesized that T cell-mediated heterologous immunity may induce asthma symptoms among sensitized individuals and used two independent in silico pipelines for the identification of cross-reactive virus- and food allergen- derived T cell epitopes, considering individual peptide sequence similarity, MHC binding affinity and immunogenicity. We assessed the proteomes of human rhinovirus (RV1b), respiratory syncytial virus (RSVA2) and influenza-strains contained in the seasonal quadrivalent influenza vaccine 2019/2020 (QIV 2019/2020), as well as SARS-CoV-2 for human HLA alleles, in addition to more than 200 most common food allergen protein sequences. All resulting allergen-derived peptide candidates were subjected to an elaborate scoring system considering multiple criteria, including clinical relevance. In both bioinformatics approaches, we found that shortlisted peptide pairs that are potentially binding to MHC class II molecules scored up to 10 × lower compared to MHC class I candidate epitopes. For MHC class I food allergen epitopes, several potentially cross-reactive peptides from shrimp, kiwi, apple, soybean and chicken were identified. The shortlisted set of peptide pairs may be implicated in heterologous immune responses and translated to peptide immunization strategies with immunomodulatory properties.

La presente investigación tuvo como objetivo establecer cómo incide el entorno virtual y el pensamiento creativo en el desarrollo de competencias matemáticas de docentes del nivel primaria de una Unidad de Gestión Educativa Local UGEL de Lima en 2022. El estudio es de enfoque cuantitativo, diseño no experimental y transversal; se llevó a cabo en una población de 210 docentes y una muestra por conveniencia de 83 docentes. Se usó el cuestionario con validez y confiabilidad. La investigación concluye que el entorno virtual y el pensamiento creativo inciden en el desarrollo de las competencias matemáticas de docentes de una UGEL de Lima Metropolitana.

Abstract The outbreak of the new severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is a public health emergency. Asthma does not represent a risk factor for COVID-19 in several published cohorts. We hypothesized that the SARS-CoV-2 proteome contains T cell epitopes, which are potentially cross-reactive to allergen epitopes. We aimed at identifying homologous peptide sequences by means of two distinct complementary bioinformatics approaches. Pipeline 1 included prediction of MHC Class I and Class II epitopes contained in the SARS-CoV-2 proteome and allergens along with alignment and elaborate ranking approaches. Pipeline 2 involved alignment of SARS-CoV-2 overlapping peptides with known allergen-derived T cell epitopes. Our results indicate a large number of MHC Class I epitope pairs including known as well as de novo predicted allergen T cell epitopes with high probability for cross-reactivity. Allergen sources, such as Aspergillus fumigatus, Phleum pratense and Dermatophagoides species are of particular interest due to their association with multiple cross-reactive candidate peptides, independently of the applied bioinformatic approach. In contrast, peptides derived from food allergens, as well as MHC class II epitopes did not achieve high in silico ranking and were therefore not further investigated. Our findings warrant further experimental confirmation along with examination of the functional importance of such cross-reactive responses.

Objectives: To describe structural barriers to mental health specialists and consequences of these barriers to care for patients with dementia and neuropsychological symptoms and their primary care physicians (PCPs).Design: Cross-sectional qualitative interview study of PCPs.Setting: Physicians' offices, primarily managed care.Participants: Forty PCPs in Northern California.Measurements: Open-ended interviews lasted 30-60 minutes. The interview guide covered clinician background, practice setting, clinical care of a particular patient, and general approach to managing patients with Alzheimer disease or related dementias.Interviews were transcribed and themes reflecting referrals identified.Results: Ninety-three percentage of the PCPs described problematic access to and communication with mental health specialists (in particular psychiatrists and neuropsychologists) as impediments to effective care for dementia patients. Thematic analysis identified structural barriers to mental health referrals ranging from problems with managed care and reimbursement policies to lack of trained providers and poor geographic distribution of specialists. Structural barriers compromised care for patients with dementia because the barriers limited PCP treatment options, and resources, impacted office staff and time with other patients, impeded and delayed care, and fostered poor communication and lack of coordinated care. Negative consequences for PCPs included increased frustration,conflict, and burnout.Conclusion: PCPs viewed problems created by onerous referral systems, such as mental health carve outs, as particularly burdensome for elderly patients with comorbid dementia and neuropsychiatric problems. These problems were cited by PCPs across different types of practice settings. PCPs managed treatment of neurobehavioral symptoms as best they could despite lack of specialist support. [ABSTRACT FROM AUTHOR]

Background: Declines in hearing acuity, especially in the high frequency range, often appear in middle age. The objective of this study was to characterize genetic and environmental influences that may underlie this pattern.Methods: One hundred seventy-nine monozygotic and 150 dizygotic twin pairs, ranging in age from 52 to 60 years, were selected from the Vietnam Era Twin Registry and individually tested for hearing acuity in the frequency range from 500 to 8000 Hz. Biometrical modeling was used to quantify genetic and environmental influences.Results: For individuals' better ears, approximately two-thirds (65%-70%, 95% confidence interval [CI], 46%-75%) of the variance in hearing acuity in the middle and high frequency ranges could be accounted for by genetic factors. For the individuals' poorer ear, which would be expected to show lower heritability, approximately one-half (41%-54%, 95% CI, 11%-67%) of the variance in the middle and high frequency ranges could be accounted for by genetic influences. Within a given frequency range, the same genetic factors influenced both the better and poorer ears. In contrast, although there was some overlap of genetic influences on the middle and high frequencies within a given ear, there were also some genetic influences that were specific to each frequency.Conclusions: Results suggest that genetic effects play an important role in the level of hearing loss that often appears in late middle age. These data have important implications for identifying persons who may be especially vulnerable to environmental risk factors such as noise exposure and medications with ototoxic properties. [ABSTRACT FROM AUTHOR]

Objective: We sought to ascertain whether patients' requests for antidepressants affect visit duration or history taking by primary care physicians (PCPs) for patients with depressive symptoms and a coexisting musculoskeletal disorder and to determine whether more thorough history taking is associated with diagnostic accuracy or with provision of minimally acceptable initial care for major depression.Design: This was a randomized trial using standardized patients (SPs). Six roles involved 2 conditions (major depression and adjustment disorder, both with coexisting musculoskeletal conditions) and 3 patient request types (brand-specific, general, or none). We conducted the study in 152 PCP offices in Northern California and Rochester, New York. Physicians were assigned randomly to see 2 SPs with depression/wrist pain or adjustment disorder/back pain.Main Outcome Measures: Physician history-taking for depression and the musculoskeletal condition; depression diagnosis in the medical record; antidepressant prescriptions/samples; referral/follow-up recommendations; visit duration; and provision of minimally acceptable initial depression care.Results: General antidepressant requests were associated with more depression history-taking (Adjusted Parameter Estimate = 0.80 more questions of 10 (95% confidence interval = 0.31-1.29, P < 0.001); brand-specific requests were marginally associated with more depression history-taking (Adjusted Parameter Estimate = 0.45, 95% confidence interval = -0.04-0.93, P = 0.07). Antidepressant medication requests were not related to musculo-skeletal question asking (P > 0.3) or visit length (P > 0.8). Depression history taking was directly associated with the likelihood of a chart diagnosis of depression and the provision of minimally acceptable initial depression care.Conclusion: General antidepressant requests increase depression history taking, including screening for suicide. Patients' requests for medication do not appear to short-circuit history taking for depression or distract the physician's attention from coexisting musculoskeletal conditions. [ABSTRACT FROM AUTHOR]

Context: Direct-to-consumer (DTC) advertising of prescription drugs in the United States is both ubiquitous and controversial. Critics charge that it leads to overprescribing, while proponents counter that it helps avert underuse of effective treatments, especially for conditions that are poorly recognized or stigmatized.Objective: To ascertain the effects of patients' DTC-related requests on physicians' initial treatment decisions in patients with depressive symptoms.Design: Randomized trial using standardized patients (SPs). Six SP roles were created by crossing 2 conditions (major depression or adjustment disorder with depressed mood) with 3 request types (brand-specific, general, or none).Setting: Offices of primary care physicians in Sacramento, Calif; San Francisco, Calif; and Rochester, NY, between May 2003 and May 2004.Participants: One hundred fifty-two family physicians and general internists recruited from solo and group practices and health maintenance organizations; cooperation rates ranged from 53% to 61%.Interventions: The SPs were randomly assigned to make 298 unannounced visits, with assignments constrained so physicians saw 1 SP with major depression and 1 with adjustment disorder. The SPs made a brand-specific drug request, a general drug request, or no request (control condition) in approximately one third of visits.Main Outcome Measures: Data on prescribing, mental health referral, and primary care follow-up obtained from SP written reports, visit audiorecordings, chart review, and analysis of written prescriptions and drug samples. The effects of request type on prescribing were evaluated using contingency tables and confirmed in generalized linear mixed models that accounted for clustering and adjusted for site, physician, and visit characteristics.Results: Standardized patient role fidelity was excellent, and the suspicion rate that physicians had seen an SP was 13%. In major depression, rates of antidepressant prescribing were 53%, 76%, and 31% for SPs making brand-specific, general, and no requests, respectively (P<.001). In adjustment disorder, antidepressant prescribing rates were 55%, 39%, and 10%, respectively (P<.001). The results were confirmed in multivariate models. Minimally acceptable initial care (any combination of an antidepressant, mental health referral, or follow-up within 2 weeks) was offered to 98% of SPs in the major depression role making a general request, 90% of those making a brand-specific request, and 56% of those making no request (P<.001).Conclusions: Patients' requests have a profound effect on physician prescribing in major depression and adjustment disorder. Direct-to-consumer advertising may have competing effects on quality, potentially both averting underuse and promoting overuse. [ABSTRACT FROM AUTHOR]

Several alkylating agents that either occur in the environment or are self-produced can cause DNA-damaging injuries in bacterial cells. Therefore, all microorganisms have developed repair systems that are able to counteract DNA alkylation damage. The adaptive response to alkylation stress in Escherichia coli consists of the Ada operon, which has been widely described; however, the homologous system in Mycobacterium tuberculosis (MTB) has been shown to have a different genetic organization but it is still largely unknown. In order to describe the defense system of MTB, we first investigated the proteins involved in the repair mechanism in the homologous non-pathogenic mycobacterium M. smegmatis. Ogt, Ada-AlkA and FadE8 proteins were recombinantly produced, purified and characterized. The biological role of Ogt was examined using proteomic experiments to identify its protein partners in vivo under stress conditions. Our results suggested the formation of a functional complex between Ogt and Ada-AlkA, which was confirmed both in silico by docking calculations and by gel filtration chromatography. We propose that this stable association allows the complex to fulfill the biological roles exerted by Ada in the homologous E. coli system. Finally, FadE8 was demonstrated to be structurally and functionally related to its E. coli homologous, AidB.

Besides most common signs and symptoms suggesting a colic cancer, sometimes the clinical presentation can be difficult. Extra-abdominal abscess as a first sign of perforated colon carcinoma is a very unusual finding. We report a case of an old male patient, in bad general condition, with a post-traumatic finding of right lumbar abscess. After the percutaneous drainage with discharge of fecal material and a postponed explorative laparotomy, we discovered a perforated right colon carcinoma with a covered perforation affecting the duodenum wall and spreading to the hepatic bedand over to the back lumbar muscular wall. Because of the diffusion of the tumor, the patient was treated with palliative surgery with duodenum suture, right colon segment resection and subsequent ileocolic anastomosis with an uneventful postoperative course. The patient died 2 months later because of neoplastic cachexia.

Resampling algorithms provide an empirical, non-parametric approach to determine the statistical significance of annotations in different experimental settings. ResA(3) (Resampling Analysis of Arbitrary Annotations, short: ResA) is a novel tool to facilitate the analysis of enrichment and regulation of annotations deposited in various online resources such as KEGG, Gene Ontology and Pfam or any kind of classification. Results are presented in readily accessible navigable table views together with relevant information for statistical inference. The tool is able to analyze multiple types of annotations in a single run and includes a Gene Ontology annotation feature. We successfully tested ResA using a dataset obtained by measuring incorporation rates of stable isotopes into proteins in intact animals. ResA complements existing tools and will help to evaluate the increasing number of large-scale transcriptomics and proteomics datasets (resa.mpi-bn.mpg.de).

We combined experimental cognitive and behavior genetic methods to investigate storage and executive components of working memory in 663 middle-aged male twins. A single latent factor model indicated that digits forward (storage) and two-digit transformation (executive + storage) scores were influenced by the same genes. Additional executive demands in digit transformation appeared to increase the variance of individual genetic differences from 25% for digits forward to 48% and 53% for the digit transformation scores. Although it was not the best model, a two-factor model also provided a good fit to the data. This model suggested the possibility of a second set of genes specifically influencing the executive component. We discuss the findings in the context of research suggesting that new genetic influences come into play if demand continues to increase beyond a certain threshold, a threshold that may change with task difficulty and with age. [ABSTRACT FROM AUTHOR]

The objective was to determine whether obstetric opinion leaders can be identified and to characterize them in terms of their demographic and professional characteristics and their attitudes toward caesarean delivery. In late 1998, we surveyed 527 obstetricians, 138 family physicians, and 80 certified nurse midwives (overall response rate, 57.8%) practicing in a stratified random sample of California hospitals with at least 1000 annual deliveries (n=52). Participants reported on demographic and professional characteristics and attitudes towards caesarean delivery; they also checked off those hospital colleagues from whom they had sought or would seek advice on labour and delivery. A composite measure of nomination frequency was used to characterize each respondent's degree of 'opinion leadership'. All analyses were corrected for the complex survey design. Using a nomination cutoff of 0.4 (0-1 scale), opinion leaders were identified in 31% of California hospitals; they were identified in 81% of hospitals using a cutoff of 0.2. Compared with their peers in the lowest fifth of the nomination distribution, clinicians in the top fifth were younger and more likely to be male, to speak English as a first language, to practice obstetrics, to have a maternal-foetal medicine subspecialty, and to practice in higher volume hospitals (p<0.05). Regardless of discipline, opinion leaders held attitudes concordant with reducing the caesarean delivery rate more often than non-opinion leaders. However, only 48% of obstetrical opinion leaders would support reducing the caesarean delivery rate to levels targeted by Healthy People 2000. In conclusion, obstetric opinion leaders could be identified in many California hospitals. However, they did not consistently support policies designed to reduce the caesarean delivery rate. The results have implications for the generalizability of opinion leader strategies. [ABSTRACT FROM AUTHOR]

Background: Chronic pain leads to tau accumulation and hippocampal atrophy, which may be moderated through inflammation. In older men, we examined associations of chronic pain with Alzheimer's disease (AD)-related plasma biomarkers and hippocampal volume as moderated by systemic inflammation., Methods: Participants were men without dementia. Chronic pain was defined as moderate-to-severe pain in 2+ study waves at average ages 56, 62, and 68. At age 68, we measured plasma amyloid-beta (Aβ42, n = 871), Aβ40 (n = 887), total tau (t-tau, n = 841), and neurofilament light chain (NfL, n = 915), and serum high-sensitivity C-reactive protein (hs-CRP, n = 968), a marker of systemic inflammation. A subgroup underwent structural MRI to measure hippocampal volume (n = 385). Analyses adjusted for medical morbidities, depressive symptoms, and opioid use., Results: Chronic pain was related to higher Aβ40 (β = 0.25, p = .009), but hs-CRP was unrelated to AD-related biomarkers (ps > .05). There was a significant interaction such that older men with both chronic pain and higher levels of hs-CRP had higher levels of Aβ42 (β = 0.36, p = .001) and Aβ40 (β = 0.29, p = .003). Chronic pain and hs-CRP did not interact to predict levels of Aβ42/Aβ40, t-tau, or NfL. Furthermore, there were significant interactions such that Aβ42 and Aβ40 were associated with lower hippocampal volume, particularly when levels of hs-CRP were elevated (hs-CRP × Aβ42: β = -0.19, p = .002; hs-CRP × Aβ40: β = -0.21, p = .001), regardless of chronic pain status., Conclusions: Chronic pain was associated with higher plasma Aβ, especially when hs-CRP was also elevated. Higher hs-CRP and Aβ levels were both related to smaller hippocampal volumes. Chronic pain, when accompanied by systemic inflammation, may elevate the risk of neurodegeneration in AD-vulnerable regions., (© The Author(s) 2024. Published by Oxford University Press on behalf of The Gerontological Society of America.)

Objectives: Childhood disadvantage is associated with lower general cognitive ability (GCA) and brain structural differences in midlife and older adulthood. However, the neuroanatomical mechanisms underlying childhood disadvantage effects on later-life GCA remain poorly understood. Although total surface area (SA) has been linked to lifespan GCA differences, total SA does not capture the non-uniform nature of childhood disadvantage effects on neuroanatomy, which varies across unimodal and transmodal cortices. Here, we examined whether cortical SA profile-the extent to which the spatial patterning of SA deviates from the normative unimodal-transmodal cortical organization-is a mediator of childhood disadvantage effects on later-life GCA., Method: In 477 community-dwelling men aged 56-72 years old, childhood disadvantage index (CDI) was derived from four indicators of disadvantages and GCA was assessed using a standardized test. Cortical SA was obtained from structural magnetic resonance imaging. For cortical SA profile, we calculated the spatial similarity between maps of individual cortical SA and MRI-derived principal gradient (i.e., unimodal-transmodal organization). Mediation analyses were conducted to examine the indirect effects of CDI through cortical SA profile on GCA., Results: Around 1.31% of CDI effects on later-life GCA were mediated by cortical SA profile, whereas total SA did not. Higher CDI was associated with more deviation of the cortical SA spatial patterning from the principal gradient, which in turn related to lower later-life GCA., Discussion: Childhood disadvantage may contribute to later-life GCA differences partly by influencing the spatial patterning of cortical SA in a way that deviates from the normative cortical organizational principle., (© The Author(s) 2024. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

Background: Early identification of Alzheimer's disease (AD) risk is critical for improving treatment success. Cortical thickness is a macrostructural measure used to assess neurodegeneration in AD. However, cortical microstructural changes appear to precede macrostructural atrophy and may improve early risk identification. Currently, whether cortical microstructural changes in aging are linked to vulnerability to AD pathophysiology remains unclear in nonclinical populations, who are precisely the target for early risk identification., Methods: In 194 adults, we calculated magnetic resonance imaging-derived maps of changes in cortical mean diffusivity (microstructure) and cortical thickness (macrostructure) over 5 to 6 years (mean age: time 1 = 61.82 years; time 2 = 67.48 years). Episodic memory was assessed using 3 well-established tests. We obtained positron emission tomography-derived maps of AD pathology deposition (amyloid-β, tau) and neurotransmitter receptors (cholinergic, glutamatergic) implicated in AD pathophysiology. Spatial correlational analyses were used to compare pattern similarity among maps., Results: Spatial patterns of cortical macrostructural changes resembled patterns of cortical organization sensitive to age-related processes (r = -0.31, p < .05), whereas microstructural changes resembled the patterns of tau deposition in AD (r = 0.39, p = .038). Individuals with patterns of microstructural changes that more closely resembled stereotypical tau deposition exhibited greater memory decline (β = 0.22, p = .029). Microstructural changes and AD pathology deposition were enriched in areas with greater densities of cholinergic and glutamatergic receptors (ps < .05)., Conclusions: Patterns of cortical microstructural changes were more AD-like than patterns of macrostructural changes, which appeared to reflect more general aging processes. Microstructural changes may better inform early risk prediction efforts as a sensitive measure of vulnerability to pathological processes prior to overt atrophy and cognitive decline., (Copyright © 2024 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.)

Neurofilament light chain (NfL) levels in circulation have been established as a sensitive biomarker of neuro-axonal damage across a range of neurodegenerative disorders. Elucidation of the genetic architecture of blood NfL levels could provide new insights into molecular mechanisms underlying neurodegenerative disorders. In this meta-analysis of genome-wide association studies (GWAS) of blood NfL levels from eleven cohorts of European ancestry, we identify two genome-wide significant loci at 16p12 (UMOD) and 17q24 (SLC39A11). We observe association of three loci at 1q43 (FMN2), 12q14, and 12q21 with blood NfL levels in the meta-analysis of African-American ancestry. In the trans-ethnic meta-analysis, we identify three additional genome-wide significant loci at 1p32 (FGGY), 6q14 (TBX18), and 4q21. In the post-GWAS analyses, we observe the association of higher NfL polygenic risk score with increased plasma levels of total-tau, Aβ-40, Aβ-42, and higher incidence of Alzheimer's disease in the Rotterdam Study. Furthermore, Mendelian randomization analysis results suggest that a lower kidney function could cause higher blood NfL levels. This study uncovers multiple genetic loci of blood NfL levels, highlighting the genes related to molecular mechanism of neurodegeneration., (© 2024. The Author(s).)

We examined how brain reserve in midlife, measured by brain-predicted age difference scores (Brain-PADs), predicted executive function concurrently and longitudinally into early old age, and whether these associations were moderated by young adult cognitive reserve or APOE genotype. 508 men in the Vietnam Era Twin Study of Aging (VETSA) completed neuroimaging assessments at mean age 56 and six executive function tasks at mean ages 56, 62, and 68 years. Results indicated that greater brain reserve at age 56 was associated with better concurrent executive function (r=.10, p=.040) and less decline in executive function over 12 years (r=.34, p=.001). These associations were not moderated by cognitive reserve or APOE genotype. Twin analysis suggested associations with executive function slopes were driven by genetic influences. Our findings suggest that greater brain reserve allowed for better cognitive maintenance from middle- to old age, driven by a genetic association. The results are consistent with differential preservation of executive function based on brain reserve that is independent of young adult cognitive reserve or APOE genotype., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

The prevalence of white matter disease increases with age and is associated with cerebrovascular disease, cognitive decline, and risk for dementia. MRI measures of abnormal signal in the white matter (AWM) provide estimates of damage, however, regional patterns of AWM may be differentially influenced by genetic or environmental factors. With our data-driven regional parcellation approach, we created a probability distribution atlas using Vietnam Era Twin Study of Aging (VETSA) data (n = 475, mean age 67.6 years) and applied a watershed algorithm to define separate regional parcellations. We report biometrical twin modeling for five anatomically distinct regions: (1) Posterior, (2) Superior frontal and parietal, (3) Anterior and inferior frontal with deep areas, (4) Occipital, and (5) Anterior periventricular. We tested competing multivariate hypotheses to identify unique influences and to explain sources of covariance among the parcellations. Family aggregation could be entirely explained by additive genetic influences, with additive genetic variance (heritability) ranging from 0.69 to 0.79. Most genetic correlations between parcellations ranged from moderate to high (r g  = 0.57-0.85), although two were small (r g  = 0.35-0.39), consistent with varying degrees of unique genetic influences. This proof-of-principle investigation demonstrated the value of our novel, data-driven parcellations, with identifiable genetic and environmental differences, for future exploration., (© 2024 Wiley Periodicals LLC.)

Multivariate network-based analytic methods such as weighted gene co-expression network analysis are frequently applied to human and animal gene-expression data to estimate the first principal component of a module, or module eigengene (ME). MEs are interpreted as multivariate summaries of correlated gene-expression patterns and network connectivity across genes within a module. As such, they have the potential to elucidate the mechanisms by which molecular genomic variation contributes to individual differences in complex traits. Although increasingly used to test for associations between modules and complex traits, the genetic and environmental etiology of MEs has not been empirically established. It is unclear if, and to what degree, individual differences in blood-derived MEs reflect random variation versus familial aggregation arising from heritable or shared environmental influences. We used biometrical genetic analyses to estimate the contribution of genetic and environmental influences on MEs derived from blood lymphocytes collected on a sample of N = 661 older male twins from the Vietnam Era Twin Study of Aging (VETSA) whose mean age at assessment was 67.7 years (SD = 2.6 years, range = 62-74 years). Of the 26 detected MEs, 14 (56%) had statistically significant additive genetic variation with an average heritability of 44% (SD = 0.08, range = 35%-64%). Despite the relatively small sample size, this demonstration of significant family aggregation including estimates of heritability in 14 of the 26 MEs suggests that blood-based MEs are reliable and merit further exploration in terms of their associations with complex traits and diseases., (© 2024 The Author(s). American Journal of Medical Genetics Part B: Neuropsychiatric Genetics published by Wiley Periodicals LLC.)

We tested if cognitive and brain reserve and maintenance explain individual differences in episodic memory and other cognitive domains from late middle to early older adulthood. We used The Vietnam Era Twin Study of Aging data (n=1604 men) with episodic memory measured at mean ages of 56, 62 and 68 years, and magnetic resonance imaging data for a subsample of participants (n=321). Cognitive reserve -young adult general cognitive ability at a mean age of 20 years and, to a lesser degree, educational attainment- was positively related to episodic memory performance at each assessment, but not to memory change. We found no evidence for the associations of brain reserve or brain maintenance on memory change. Results were highly similar when looking at processing speed, executive function and verbal fluency. In conclusion, higher young adult cognitive reserve was related to better episodic memory in midlife and older adulthood, but it did not confer better cognitive maintenance with respect to memory. This supports the importance of early cognitive development in dementia prevention., Competing Interests: Declaration of Competing Interest The authors have no actual or potential conflicts of interest., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: Increased exposure to ambient air pollution, especially fine particulate matter ≤ 2.5 μ m ( PM 2.5 ) 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 PM 2.5 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 PM 2.5 and in vivo magnetic resonance imaging (MRI) estimates of LC structural integrity indexed by contrast to noise ratio ( LC CNR ) in 381 men [ mean age = 67.3 ; standard deviation ( SD ) = 2.6 ] from the Vietnam Era Twin Study of Aging (VETSA). Exposure to PM 2.5 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 LC CNR in the rostral-middle portion of LC due to its stronger associations with aging and AD than the caudal LC. Associations between PM 2.5 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 PM 2.5 and rostral-middle LC CNR ( β = - 0.16 ; p = 0.02 ), whereby higher exposure to PM 2.5 was associated with lower LC CNR . A co-twin control analysis found that, within monozygotic pairs, individuals with higher PM 2.5 exposure showed lower LC CNR ( β = - 0.11 ; p = 0.02 ), indicating associations were not driven by genetic or shared environmental confounds. There were no associations between PM 2.5 and caudal LC CNR 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.