White matter alterations and their associations with biomarkers and behavior in subjective cognitive decline individuals: a fixel-based analysis.

BACKGROUND: Subjective cognitive decline (SCD) is an early stage of dementia linked to Alzheimer's disease pathology. White matter changes were found in SCD using diffusion tensor imaging, but there are known limitations in voxel-wise tensor-based methods. Fixel-based analysis (FBA) can help understand changes in white matter fibers and how they relate to neurodegenerative proteins and multidomain behavior data in individuals with SCD. METHODS: Healthy adults with normal cognition were recruited in the Northeastern Taiwan Community Medicine Research Cohort in 2018-2022 and divided into SCD and normal control (NC). Participants underwent evaluations to assess cognitive abilities, mental states, physical activity levels, and susceptibility to fatigue. Neurodegenerative proteins were measured using an immunomagnetic reduction technique. Multi-shell diffusion MRI data were collected and analyzed using whole-brain FBA, comparing results between groups and correlating them with multidomain assessments. RESULTS: The final enrollment included 33 SCD and 46 NC participants, with no significant differences in age, sex, or education between the groups. SCD had a greater fiber-bundle cross-section than NC (pFWE < 0.05) at bilateral frontal superior longitudinal fasciculus II (SLFII). These white matter changes correlate negatively with plasma Aß42 level (r = -0.38, p = 0.01) and positively with the AD8 score for subjective cognitive complaints (r = 0.42, p = 0.004) and the Hamilton Anxiety Rating Scale score for the degree of anxiety (Ham-A, r = 0.35, p = 0.019). The dimensional analysis of FBA metrics and blood biomarkers found positive correlations of plasma neurofilament light chain with fiber density at the splenium of corpus callosum (pFWE < 0.05) and with fiber-bundle cross-section at the right thalamus (pFWE < 0.05). Further examination of how SCD grouping interacts between the correlations of FBA metrics and multidomain assessments showed interactions between the fiber density at the corpus callosum with letter-number sequencing cognitive score (pFWE < 0.01) and with fatigue to leisure activities (pFWE < 0.05). CONCLUSION: Based on FBA, our investigation suggests white matter structural alterations in SCD. The enlargement of SLFII's fiber cross-section is linked to plasma Aß42 and neuropsychiatric symptoms, which suggests potential early axonal dystrophy associated with Alzheimer's pathology in SCD. The splenium of the corpus callosum is also a critical region of axonal degeneration and cognitive alteration for SCD.

Vascular risk factors and astrocytic marker for the glymphatic system activity.

OBJECTIVES: Glymphatic system maintains brain fluid circulation via active transportation of astrocytic aquaporin-4 in perivascular space. The diffusion tensor imaging analysis along the perivascular space (DTI-ALPS) is an established method measuring perivascular glymphatic activity, but comprehensive investigations into its influential factors are lacking. METHODS: Community-dwelling older adults underwent brain MRI scans, neuropsychiatric, and multi-domain assessments. Blood biomarker tests included glial fibrillary acidic protein (GFAP) for astrocyte injury. RESULTS: In 71 enrolled participants, the DTI-ALPS index was associated with modifiable factors, including lipid profile (high-density lipoprotein, r = 0.396; very-low-density lipoprotein, r = - 0.342), glucose intolerance (diabetes mellitus, standardized mean difference (SMD) = 0.7662; glycated hemoglobin, r = - 0.324), obesity (body mass index, r = - 0.295; waist, r = - 0.455), metabolic syndrome (SMD = - 0.6068), cigarette-smoking (SMD = - 0.6292), and renal clearance (creatinine, r = - 0.387; blood urea nitrogen, r = - 0.303). Unmodifiable associative factors of DTI-ALPS were age (r = - 0.434) and sex (SMD = 1.0769) (all p < 0.05). A correlation of DTI-ALPS and blood GFAP was noticed (r = - 0.201, one-tailed t-test for the assumption that astrocytic injury impaired glymphatic activity, p = 0.046). Their cognitive correlations diverged, domain-specific for DTI-ALPS (Facial Memory Test, r = 0.272, p = 0.022) but global cognition-related for blood GFAP (MoCA, r = - 0.264, p = 0.026; ADAS-cog, r = 0.304, p = 0.010). CONCLUSION: This correlation analysis revealed multiple modifiable and unmodifiable association factors to the glymphatic image marker. The DTI-ALPS index correlated with various metabolic factors that are known to increase the risk of vascular diseases such as atherosclerosis. Furthermore, the DTI-ALPS index was associated with renal indices, and this connection might be a link of water regulation between the two systems. In addition, the astrocytic biomarker, plasma GFAP, might be a potential marker of the glymphatic system; however, more research is needed to confirm its effectiveness.

Normative Data of Mini-Mental State Examination, Montreal Cognitive Assessment, and Alzheimer's Disease Assessment Scale-Cognitive Subscale of Community-Dwelling Older Adults in Taiwan.

INTRODUCTION: Appropriate tools and references are essential for evaluating individuals' cognitive levels. This study validated the Taiwan version of the Alzheimer's Disease Assessment Scale-Cognitive subscale (ADAS-cog) and provided normative data for the Mini-Mental State Examination (MMSE), the Montreal Cognitive Assessment (MoCA), and ADAS-cog in community-dwelling older adults. METHODS: MMSE, MoCA, and ADAS-cog were administered to 150 nondemented healthy adults aged 55-85 years during 2018-2020 as part of the Northeastern Taiwan Community Medicine Research Cohort. ADAS-cog was translated from the original English version to traditional Chinese with cultural and language considerations in Taiwan. Cronbach's alpha (α) tested the reliability of ADAS-cog, and Pearson correlations examined its external validity using MMSE and MoCA as comparisons. Normative data were generated and stratified by age and education, and the one-way analysis of variance compared scores between age and education groups. Another 20 hospital-acquired participants with cognitive impairment joined the 150 healthy participants. Comparisons in the Clinical Dementia Rating (CDR) tiers tested the discriminability of the tests for different cognitive levels. The area under the receiver operating characteristic curve (AUROC) analyzed the power of ADAS-cog in predicting CDR 0.5 from CDR 0. RESULTS: The Taiwan version of ADAS-cog had fair reliability between items (α = 0.727) and good correlations to MMSE (r = -0.673, p < 0.001) and MoCA (r = -0.746, p < 0.001). The normative data of MMSE, MoCA, and ADAS-cog showed ladder changes with age (p = 0.006, 0.001, and 0.437) and education (p < 0.001, <0.001, and <0.001) in the 150 nondemented older adults. Next, in the 170 mixed participants from the communities and the hospital, MMSE, MoCA, and ADAS-cog scores were well differentiable between CDR 0, 0.5, and 1. In addition, ADAS-cog discriminated CDR 0.5 from 0 by an AUROC of 0.827 (p < 0.001). DISCUSSION/CONCLUSION: The three structured cognitive tests consistently reflect cognitive levels of healthy older adults. The Taiwan version of ADAS-cog is compatible with MMSE and MoCA to distinguish people with mildly impaired from normal cognition. In addition, this study derived MMSE, MoCA, and ADAS-cog norms tailored to demographic factors. The findings highlight the need for stratification of age and education rather than applying a fixed cutoff for defining normal and abnormal cognition.

Validation of the Traditional Chinese Version of the Pittsburgh Fatigability Scale for Older Adults.

OBJECTIVES: The Pittsburgh Fatigability Scale (PFS) is a self-administered 10-item tool to measure physical and mental fatigability in older adults. The aim of the current study was to validate the psychometric properties of the traditional Chinese version of PFS (TC-PFS). METHODS: We recruited 114 community-dwellingolder adults, where 35 were diagnosed with late-life depression (LLD), 26 with mild cognitive impairment (MCI), and 53 were cognitively normal (CN) from a larger community study of older adults. Statistical analyses were done separately for TC-PFS Physical and Mental subscales. Factor analysis was used for reliability, Cronbach's alpha for internal consistency, Pearson's correlation for construct validity, and group comparison for discriminative validity. RESULTS: Factor analysis revealed a two-factor structure for both the TC-PFS Physical and Mental subscales with high reliability (α = 0.89 and 0.89, respectively). Patients with LLD had the highest PFS scores, with 80.0% and 82.9% classified as having greater physical and mental fatigability. For concurrent validity, we found moderate associations with the vitality and physical functioning subscales of the 36-Item Short Form Health Survey. For convergent validity, TC-PFS showed moderate association with emotional-related psychometrics, particularly for the Physical subscale in those with LLD. In contrast, TC-PFS Mental subscale showed correlations with cognitive function, particularly in the MCI group. CONCLUSIONS: Our results indicate that the TC-PFS is a valid instrument to measure perceived physical and mental fatigability in older Taiwanese adults.Clinical implications: Perceived fatigability reflects the underlying physical, mental or cognitive function in older adults with or without depression.

Loneliness and depression dissociated on parietal-centered networks in cognitive and resting states.

BACKGROUND: Perceived loneliness, an increasingly prevalent social issue, is closely associated with major depressive disorder (MDD). However, the neural mechanisms previously implicated in key cognitive and affective processes in loneliness and MDD still remain unclear. Such understanding is critical for delineating the psychobiological basis of the relationship between loneliness and MDD. METHODS: We isolated the unique and interactive cognitive and neural substrates of loneliness and MDD among 27 MDD patients (mean age = 51.85 years, 20 females), and 25 matched healthy controls (HCs; mean age = 48.72 years, 19 females). We assessed participants' behavioral performance and neural regional and network functions on a Stroop color-word task, and their resting-state neural connectivity. RESULTS: Behaviorally, we found greater incongruence-related accuracy cost in MDD patients, but reduced incongruence effect on reaction time in lonelier individuals. When performing the Stroop task, loneliness positively predicted prefrontal-anterior cingulate-parietal connectivity across all participants, whereas MDD patients showed a decrease in connectivity compared to controls. Furthermore, loneliness negatively predicted parietal and cerebellar activities in MDD patients, but positively predicted the same activities in HCs. During resting state, MDD patients showed reduced parietal-anterior cingulate connectivity, which again positively correlated with loneliness in this group. CONCLUSIONS: We speculate the distinct neurocognitive profile of loneliness might indicate increase in both bottom-up attention and top-down executive control functions. However, the upregulated cognitive control processes in lonely individuals may eventually become exhausted, which may in turn predispose to MDD onset.

Ethnic disparity in prevalence and associated risk factors of myopia in adolescents.

BACKGROUND/PURPOSE: To examine ethnic disparity in prevalence and associated factors of myopia in adolescents using the Unites States National Health and Nutrition Examination Survey (NHANES) dataset. METHODS: Participants who were aged 12-19 years were included from NHANES (1999-2008). Logistic regression analyses were applied to identify risk factors associated with myopia after stratification by race. RESULTS: A total of 9,960 participants were included in the prevalence analysis, and 6,571 in the risk factor analysis. Other race (excluded Mexican American, other Hispanic, non-Hispanic white, non-Hispanic black) participants had the highest frequency of myopia (42.77%). Multivariate analyses of the whole population suggested that the odds of myopia were significantly lower in participants with household smokers (odds ratio [OR] = 0.79, 95% confidence interval [CI]: 0.66-0.97), and significantly greater in Mexican American race (OR = 1.28, 95% CI: 1.01-1.62), other Hispanic (OR = 1.79, 95% CI: 1.10-2.92) and in participants with senior high school graduate education (OR = 1.79, 95% CI: 1.01-3.18), watched 2 hours of television daily (OR = 1.27, 95% CI: 1.02-1.59), used the computer for 1 hour daily (OR = 1.276, 95% CI: 1.02-1.57). When examined by race/ethnicity, 1 hour of computer use increased the odds of myopia in the non-Hispanic White group, in Mexican Americans a higher family poverty income ratio and 2 hours of television time was associated with myopia, and in the Other Hispanic group, a higher family poverty income ratio was associated with myopia, while males and those with a higher sugar had a lower risk of myopia. CONCLUSION: Risk factors for myopia vary with race/ethnicity.

Masseter Muscle Volume Changes Evaluated by 3-Dimensional Computed Tomography After Repeated Botulinum Toxin A Injections in Patients With Square Facial Morphology.

INTRODUCTION: Botulinum neurotoxin A (BoNT-A) is a minimally invasive and technically straightforward treatment of masseter muscle (MM) volume reduction and facial contouring, but the literature on its long-term effect on MM volume remains unclear. OBJECTIVE: This study aimed to assess quantitatively for progressive volume changes of lower facial contour after 3 BoNT-A injections in patients with bilateral MM hypertrophy causing square facial morphology using 3-dimensional computed tomographic scans. MATERIALS AND METHODS: Ten female patients with square facial morphology due to bilateral MM hypertrophy were recruited to, and 6 completed, this clinical study. Each received 24 U of BoNT-A into the inferior portion of each MM on both sides, repeated 6 monthly to complete 3 treatments. Masseter muscle volume changes were assessed using 3-dimensional computed tomography at pretreatment (before injections) and posttreatment (1 year after the third injection). RESULTS: Mean MM volume significantly reduced from 26.39 ± 4.18 cm before treatment to 23.26 ± 4.31 cm 1 year after treatment (P = 0.002). CONCLUSION: Three consecutive 6-monthly BoNT-A injections into the MMs reduced their volume by 12% when assessed 1 year after completion of treatment.

The relationships between brain structural changes and perceived loneliness in older adults suffering from late-life depression.

OBJECTIVE: Late-life depression is a significant health risk factor for older adults, part of which is perceived loneliness. In this voxel-based morphometry study, we examined the relationships between perceived loneliness and depression recurrence. METHODS: Fifty-two older adults were recruited, and they were split into 3 groups: single episode, multiple episodes, or normal control groups, according to their clinical histories. RESULTS: This result suggests the level of functioning regarding the reward system may be negatively related to the number of depressive episodes. Taken together, the findings of this study offer important insight into the neural underpinnings of the course and chronicity of late-life depression.

The N-3 polyunsaturated fatty acids supplementation to prevent depression recurrence in patients with late-life depression: A 52-week double-blind, placebo-controlled trial.

BACKGROUND: Reports on the efficacy of omega-3 fatty acids (n-3 PUFAs) for the treatment of late-life depression (LLD) are mixed, and most studies focus on the modification of depressive symptoms rather than depression prevention. The aim of the present study was to investigate the efficacy of n-3 PUFAs in preventing depressive recurrence in patients with late-life depression. In addition, we investigated the effects of n-3 PUFAs on changes in depressive and anxiety symptoms and inflammatory markers in LLD. METHODS: A 52-week, double-blind, randomized, controlled trial was conducted. We enrolled a total of 39 euthymic patients with LLD. They were randomized to receive either n-3 PUFAs (1.2 g per day of eicosapentaenoic acid and 1 g of docosahexaenoic acid) or placebo for 52 weeks. Recurrence of depression and severity of depression symptoms were assessed at baseline and weeks 4, 8, 16, 24, 32, 40, and 52. RESULTS: A total of 39 patients completed the trial with 19 in the n-3 PUFAs group and 20 in the placebo group. Cox proportional hazard regression indicated that n-3 PUFAs had significant protective effect on depression recurrence (Hazard Ratio: 0.295, 95 % Confidence Interval: 0.093-0.931, p value =0.037). But n-3 PUFAs intervention had no significant effect in reducing depressive or anxiety symptoms, inflammatory markers over the placebo group. LIMITATION: The results should be interpreted with consideration of the modest sample size. CONCLUSION: These findings suggest that n-3 PUFAs may have a prophylactic effect in currently euthymic patients with LLD.

Life After Traumatic Brain Injury: Effects on the Lifestyle and Quality of Life of Community-Dwelling Patients.

Persons who have experienced traumatic brain injury (TBI) may encounter a range of changes in their physical, mental, and cognitive functions as well as high fatigue levels. To gain a comprehensive understanding of the challenges faced by persons after TBI, we conducted multi-domain assessments among community-dwelling persons with a history of TBI and compared them with age- and sex-matched controls from the Northeastern Taiwan Community Medicine Research Cohort between 2019 and 2021. A total of 168 persons with TBI and 672 non-TBI controls were not different in terms of demographics, comorbidities, and physiological features. However, compared with the non-TBI group, the TBI group had a distinct lifestyle that involved increased reliance on analgesics (6.9% vs. 15.0%, respectively; p = 0.001) and sleep aids (p = 0.008), which negatively affected their quality of life. Moreover, they consumed more coffee (p < 0.001), tea (p < 0.001), cigarettes (p = 0.002), and betel nuts (p = 0.032) than did the non-TBI group. Notably, the use of coffee had a positive effect on the quality of life of the TBI group (F = 4.034; p = 0.045). Further, compared with the non-TBI group, the TBI group had increased risks of sarcopenia (p = 0.003), malnutrition (p = 0.003), and anxiety (p = 0.029) and reduced blood levels of vitamin D (29.83 ± 10.39 vs. 24.20 ± 6.59 ng/mL, respectively; p < 0.001). Overall, the TBI group had a reduced health-related quality of life, with significant challenges related to physical health, mental well-being, social interactions, pain management, and fatigue levels. Moreover, the TBI group experienced poorer sleep quality and efficiency than did the non-TBI group. In conclusion, persons who have sustained brain injuries that require comprehensive and holistic care that includes lifestyle modification, mental and physical healthcare plans, and increased long-term support from their communities. ClinicalTrials.gov (identifier: NCT04839796).

User-Friendly Chatbot to Mitigate the Psychological Stress of Older Adults During the COVID-19 Pandemic: Development and Usability Study.

BACKGROUND: To safeguard the most vulnerable individuals during the COVID-19 pandemic, numerous governments enforced measures such as stay-at-home orders, social distancing, and self-isolation. These social restrictions had a particularly negative effect on older adults, as they are more vulnerable and experience increased loneliness, which has various adverse effects, including increasing the risk of mental health problems and mortality. Chatbots can potentially reduce loneliness and provide companionship during a pandemic. However, existing chatbots do not cater to the specific needs of older adult populations. OBJECTIVE: We aimed to develop a user-friendly chatbot tailored to the specific needs of older adults with anxiety or depressive disorders during the COVID-19 pandemic and to examine their perspectives on mental health chatbot use. The primary research objective was to investigate whether chatbots can mitigate the psychological stress of older adults during COVID-19. METHODS: Participants were older adults belonging to two age groups (≥65 years and <65 years) from a psychiatric outpatient department who had been diagnosed with depressive or anxiety disorders by certified psychiatrists according to the Diagnostic and Statistical Manual of Mental Disorders (Fifth Edition) (DSM-5) criteria. The participants were required to use mobile phones, have internet access, and possess literacy skills. The chatbot's content includes monitoring and tracking health data and providing health information. Participants had access to the chatbot for at least 4 weeks. Self-report questionnaires for loneliness, depression, and anxiety were administered before and after chatbot use. The participants also rated their attitudes toward the chatbot. RESULTS: A total of 35 participants (mean age 65.21, SD 7.51 years) were enrolled in the trial, comprising 74% (n=26) female and 26% (n=9) male participants. The participants demonstrated a high utilization rate during the intervention, with over 82% engaging with the chatbot daily. Loneliness significantly improved in the older group ≥65 years. This group also responded positively to the chatbot, as evidenced by changes in University of California Los Angeles Loneliness Scale scores, suggesting that this demographic can derive benefits from chatbot interaction. Conversely, the younger group, <65 years, exhibited no significant changes in loneliness after the intervention. Both the older and younger age groups provided good scores in relation to chatbot design with respect to usability (mean scores of 6.33 and 6.05, respectively) and satisfaction (mean scores of 5.33 and 5.15, respectively), rated on a 7-point Likert scale. CONCLUSIONS: The chatbot interface was found to be user-friendly and demonstrated promising results among participants 65 years and older who were receiving care at psychiatric outpatient clinics and experiencing relatively stable symptoms of depression and anxiety. The chatbot not only provided caring companionship but also showed the potential to alleviate loneliness during the challenging circumstances of a pandemic.

Associations of depression and perceived physical fatigability with white matter integrity in older adults.

BACKGROUNDS: Fatigability is prevalent in older adults. However, it is often associated with depressed mood. We aim to investigate these two psychobehavioral constructs by examining their underpinning of white matter structures in the brain and their associations with different medical conditions. METHODS: Twenty-seven older adults with late-life depression (LLD) and 34 cognitively normal controls (CN) underwent multi-shell diffusion MRI. Fatigability was measured with the Pittsburgh Fatigability Scale. We examined white matter integrity by measuring the quantitative anisotropy (QA), a fiber tracking parameter with better accuracy than the traditional imaging technique. RESULTS: We found those with LLD had lower QA in the 2nd branch of the left superior longitudinal fasciculus (SLF-II), and those with more physical fatigability had lower QA in more widespread brain regions. In tracts associated with more physical fatigability, the lower QA in left acoustic radiation and left superior thalamic radiation correlated with higher blood glucose (r = - 0.46 and - 0.49). In tracts associated with depression, lower QA in left SLF-II correlated with higher bilirubin level (r = - 0.58). DISCUSSION: Depression and fatigability were associated with various white matter integrity changes, which correlated with biochemistry biomarkers all related to inflammation.

Predicting suicidality in late-life depression by 3D convolutional neural network and cross-sample entropy analysis of resting-state fMRI.

BACKGROUND: Predicting suicide is a pressing issue among older adults; however, predicting its risk is difficult. Capitalizing on the recent development of machine learning, considerable progress has been made in predicting complex behavior such as suicide. As depression remained the strongest risk for suicide, we aimed to apply deep learning algorithms to identify suicidality in a group with late-life depression (LLD). METHODS: We enrolled 83 patients with LLD, 35 of which were non-suicidal and 48 were suicidal, including 26 with only suicidal ideation and 22 with past suicide attempts, for resting-state functional magnetic resonance imaging (MRI). Cross-sample entropy (CSE) analysis was conducted to examine the complexity of MRI signals among brain regions. Three-dimensional (3D) convolutional neural networks (CNNs) were used, and the classification accuracy in each brain region was averaged to predict suicidality after sixfold cross-validation. RESULTS: We found brain regions with a mean accuracy above 75% to predict suicidality located mostly in default mode, fronto-parietal, and cingulo-opercular resting-state networks. The models with right amygdala and left caudate provided the most reliable accuracy in all cross-validation folds, indicating their neurobiological importance in late-life suicide. CONCLUSION: Combining CSE analysis and the 3D CNN, several brain regions were found to be associated with suicidality.

Enhancement of antibacterial activity in electrospun fibrous membranes based on quaternized chitosan with caffeic acid and berberine chloride for wound dressing applications.

Electrospun nanofibers made from chitosan are promising materials for surgical wound dressings due to their non-toxicity and biocompatibility. However, the antibacterial activity of chitosan is limited by its poor water solubility under physiological conditions. This study addresses this issue by producing electrospun nanofibers mainly from natural compounds, including chitosan and quaternized chitosan, which enhance both its solubility for electrospinning and the antibacterial activity of the resulting electrospun nanofibers. Additionally, antimicrobial agents like caffeic acid or berberine chloride were incorporated. The glutaraldehyde-treated nanofibers showed improved mechanical properties, with an average tensile strength exceeding 2.7 MPa, comparable to other chitosan-based wound dressings. They also demonstrated enhanced water stability, retaining over 50% of their original weight after one week in phosphate-buffered saline (PBS) at 37 °C. The morphology and performance of these nanofibers were thoroughly examined and discussed. Furthermore, these membranes displayed rapid drug release, indicating potential for inhibiting bacterial growth. Antibacterial assays revealed that S2-CX nanofibers containing caffeic acid were most effective against E. coli and S. aureus, reducing their survival rates to nearly 0%. Similarly, berberine chloride-containing S4-BX nanofibers reduced the survival rates of E. coli and S. aureus to 19.82% and 0%, respectively. These findings suggest that electrospun membranes incorporating chitosan and caffeic acid hold significant potential for use in antibacterial wound dressings and drug delivery applications.

Differential neuropsychiatric associations of plasma biomarkers in older adults with major depression and subjective cognitive decline.

Older adults with major depressive disorder (MDD) or early cognitive decline during the subjective cognitive decline (SCD) stage may exhibit neuropsychiatric symptoms such as anxiety, depression, and subtle cognitive impairment. The clinicopathological features and biological mechanisms of MDD differ from those of SCD among older adults; these conditions thus require different treatment strategies. This study enrolled 82 participants above 50 years old with normal cognitive levels from the communities to examine biomarker-behavior correlations between MDD (n = 23) and SCD (n = 23) relative to a normal control (NC) group (n = 36). Multidomain assessments were performed for all participants, including immunomagnetic reduction tests to detect plasma beta-amyloid (Aß), total tau (Tau), phosphorylated tau-181 (p-Tau181), neurofilament light chain, and glial fibrillary acidic protein (GFAP). This study observed that depressive symptoms in MDD were associated with amyloid pathology (plasma Aß40 vs. HADS-D: R = 0.45, p = 0.031; Aß42/Aß40 vs. HADS-D: R = -0.47, p = 0.024), which was not observed in the NC (group difference p < 0.05). Moreover, cognitive decline in MDD was distinguished by a mixed neurodegenerative process involving amyloid (plasma Aß42 vs. facial memory test: R = 0.48, p = 0.025), tau (Tau/Aß42 vs. digit symbol substitution test (DSST): R = -0.53, p = 0.01), and astrocytic injury (plasma GFAP vs. Montreal cognitive assessment score: R = -0.44, p = 0.038; plasma GFAP vs. DSST: R = -0.52, p = 0.014), findings that did not apply to the NC (group difference p < 0.05). Moreover, this study revealed different biomarker-behavior correlations between individuals with SCD and the NC. Compared with the NC, cognitive decline in the SCD group might be unrelated to amyloid pathology and instead might be early manifestations of tau pathology. This study underscores the difference in clinicopathological features between MDD and SCD among older adults, which differ from those of the NC. These findings enhance our understanding of the mechanisms underlying MDD and SCD in older individuals.

Cognitive protection and brain entropy changes from omega-3 polyunsaturated fatty acids supplement in late-life depression: A 52-week randomized controlled trial.

BACKGROUND: Late-life depression (LLD) is associated with risk of dementia, yet intervention of LLD provides an opportunity to attenuate subsequent cognitive decline. Omega-3 polyunsaturated fatty acids (PUFAs) supplement is a potential intervention due to their beneficial effect in depressive symptoms and cognitive function. To explore the underlying neural mechanism, we used resting-state functional MRI (rs-fMRI) before and after omega-3 PUFAs supplement in older adults with LLD. METHODS: A 52-week double-blind randomized controlled trial was conducted. We used multi-scale sample entropy to analyze rs-fMRI data. Comprehensive cognitive tests and inflammatory markers were collected to correlate with brain entropy changes. RESULTS: A total of 20 patients completed the trial with 11 under omega-3 PUFAs and nine under placebo. While no significant global cognitive improvement was observed, a marginal enhancement in processing speed was noted in the omega-3 PUFAs group. Importantly, participants receiving omega-3 PUFAs exhibited decreased brain entropy in left posterior cingulate gyrus (PCG), multiple visual areas, the orbital part of the right middle frontal gyrus, and the left Rolandic operculum. The brain entropy changes of the PCG in the omega-3 PUFAs group correlated with improvement of language function and attenuation of interleukin-6 levels. LIMITATIONS: Sample size is small with only marginal clinical effect. CONCLUSION: These findings suggest that omega-3 PUFAs supplement may mitigate cognitive decline in LLD through anti-inflammatory mechanisms and modulation of brain entropy. Larger clinical trials are warranted to validate the potential therapeutic implications of omega-3 PUFAs for deterring cognitive decline in patients with late-life depression.

A topological Hund nodal line antiferromagnet.

The interplay of topology, magnetism, and correlations gives rise to intriguing phases of matter. In this study, through state-of-the-art angle-resolved photoemission spectroscopy, density functional theory, and dynamical mean-field theory calculations, we visualize a fourfold degenerate Dirac nodal line at the boundary of the bulk Brillouin zone in the antiferromagnet YMn2Ge2. We further demonstrate that this gapless, antiferromagnetic Dirac nodal line is enforced by the combination of magnetism, space-time inversion symmetry, and nonsymmorphic lattice symmetry. The corresponding drumhead surface states traverse the whole surface Brillouin zone. YMn2Ge2 thus serves as a platform to exhibit the interplay of multiple degenerate nodal physics and antiferromagnetism. Interestingly, the magnetic nodal line displays a d-orbital dependent renormalization along its trajectory in momentum space, thereby manifesting Hund's coupling. Our findings offer insights into the effect of electronic correlations on magnetic Dirac nodal lines, leading to an antiferromagnetic Hund nodal line.

Potential Mobile Health Applications for Improving the Mental Health of the Elderly: A Systematic Review.

The rapid aging of the global population presents challenges in providing mental health care resources for older adults aged 65 and above. The COVID-19 pandemic has further exacerbated the global population's psychological distress due to social isolation and distancing. Thus, there is an urgent need to update scholarly knowledge on the effectiveness of mHealth applications to improve older people's mental health. This systematic review summarizes recent literature on chatbots aimed at enhancing mental health and well-being. Sixteen papers describing six apps or prototypes were reviewed, indicating the practicality, feasibility, and acceptance of chatbots for promoting mental health in older adults. Engaging with chatbots led to improvements in well-being and stress reduction, as well as a decrement in depressive symptoms. Mobile health applications addressing these studies are categorized for reference.