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BACKGROUND: Mental health in the elderly has multiple determinants, and studies indicate household and family composition, economic status, and family support are key factors. However, these are difficult to modify, and better lifestyle for the elderly can be a possible intervention. The current study examined the mediating role of lifestyle in the association between these three types of the household and family composition (living alone, living with a spouse, and living with children) and mental health in older adults. METHODS: We studied 5,407 participants (58.7% female, age 45 + years) from the Beijing Aging Brain Rejuvenation Initiative Project. All participants underwent a battery of examinations to measure degree loneliness, depression, and global cognitive function. We also surveyed personal lifestyles. We used a mediation analysis to determine the relative contribution of each lifestyle factor on mental health outcomes. RESULTS: Older adults living alone rarely participated in mental and social activities and often had irregular diets; those adults living with children spent most of their time caring for grandchildren and had irregular eating and sleeping schedules; those living with a spouse often engaged in a variety of leisure activities and had the best life habits. Mediation analyses showed that dietary and sleeping irregularity partially mediated the negative effects of living alone on mental health, and were moderated by age and gender. CONCLUSIONS: Living with a spouse was associated with benefits for the mental health of middle-aged and older adults (especially older and female individuals), through modifying better lifestyles than those of individuals with the other two types of the household and family composition.

Previous studies have found that loneliness affects cognitive functions in older persons. However, the influence of loneliness on different cognitive fields and the internal mechanism of the relationship are unclear. A total of 4772 older persons aged above 50 years (Mean = 65.31, SD = 6.96, 57.7% female) were included in this study. All the participants completed the characteristics scale, as well as the loneliness scale, leisure activity scale, and cognitive function tests in six domains. The results showed that 17.6% of participants had high loneliness, while 16.7% of participants had low loneliness. Associations were observed between higher levels of loneliness and lower scores in general cognitive ability, memory, and executive functions. Mediation analysis suggested that leisure activities, encompassing mental, physical, and social activities, were associated with cognitive functions in the context of loneliness. These results indicate that leisure activities may play a significant role in the relationship between loneliness and cognitive functions in older adults. The study highlights the importance of considering leisure activities in this demographic to potentially mitigate the adverse cognitive effects associated with loneliness.

Background: The aging population and high rates of Alzheimer's disease (AD) create significant medical burdens, prompting a need for early prevention. Targeting modifiable risk factors like vascular risk factors (VRFs), closely linked to AD, may provide a promising strategy for intervention. Objective: This study investigates how VRFs influence cognitive performance and brain structures in a community-based cohort. Methods: In this cross-sectional study, 4,667 participants over 50 years old, drawn from the Beijing Ageing Brain Rejuvenation Initiative project, were meticulously examined. Cognitive function and VRFs (diabetes mellitus, hypertension, hyperlipidemia, obesity, and smoking), were comprehensively assessed through one-to-one interviews. Additionally, a subset of participants (n = 719) underwent MRI, encompassing T1-weighted and diffusion-weighted scans, to elucidate gray matter volume and white matter structural network organization. Results: The findings unveil diabetes as a potent detriment to memory, manifesting in atrophy within the right supramarginal gyrus and diminished nodal efficiency and degree centrality in the right inferior parietal lobe. Hypertension solely impaired memory without significant structural changes. Intriguingly, individuals with comorbid diabetes and hypertension exhibited the most pronounced deficits in both brain structure and cognitive performance. Remarkably, hyperlipidemia emerged as a factor associated with enhanced cognition, and preservation of brain structure. Conclusions: This study illuminates the intricate associations between VRFs and the varied patterns of cognitive and brain structural damage. Notably, the synergistic effect of diabetes and hypertension emerges as particularly deleterious. These findings underscore the imperative to tailor interventions for patients with distinct VRF comorbidities, especially when addressing cognitive decline and structural brain changes. [ABSTRACT FROM AUTHOR]

Objective: To create a comprehensive map of strategic lesion network localizations for neurological deficits, and identify prognostic neuroimaging biomarkers to facilitate the early detection of patients with a high risk of poor functional outcomes in acute ischemic stroke (AIS). Methods: In a large‐scale multicenter study of 7,807 patients with AIS, we performed voxel‐based lesion‐symptom mapping, functional disconnection mapping (FDC), and structural disconnection mapping (SDC) to identify distinct lesion and network localizations for National Institutes of Health Stroke Scale (NIHSS) score. Impact scores were calculated based on the odds ratios or t‐values of voxels from voxel‐based lesion‐symptom mapping, FDC, and SDC results. Ordinal regression models were used to investigate the predictive value of the impact scores on functional outcome (defined as the modified Rankin score at 3 months). Results: We constructed lesion, FDC, and SDC maps for each item of the NIHSS score, which provided insights into the neuroanatomical substrate and network localization of neurological function deficits after AIS. The lesion impact score of limb ataxia, the SDC impact score of limb deficit, and FDC impact score of sensation and dysarthria were significantly associated with modified Rankin Scale at 3 months. Adding the SDC impact score, FDC impact score, and lesion impact score to the NIHSS total score improved the performance in predicting functional outcomes, as compared with using the NIHSS score alone. Interpretation: We constructed comprehensive maps of strategic lesion network localizations for neurological deficits that were predictive of functional outcomes in AIS. These results may provide specifically localized targets for future neuromodulation therapies. ANN NEUROL 2023;94:572–584 [ABSTRACT FROM AUTHOR]

Background: Language ability differs between the sexes. However, it is unclear how this sex difference is moderated by genetic factors and how the brain interacts with genetics to support this specific language capacity. Previous studies have demonstrated that the sorting protein-related receptor (SORL1) polymorphism influences cognitive function and brain structure differently in males and females and is associated with Alzheimer's disease risk. Objective: The aim of this study was to investigate the effects of sex and the SORL1 rs1699102 (CC versus T carriers) genotype on language. Methods: 103 non-demented Chinese older adults from Beijing Aging Brain Rejuvenation Initiative (BABRI) database were included in this study. Participants completed language tests, T1-weighted structural magnetic resonance imaging (MRI) and resting-state functional MRI. Language test performance, gray matter volume, and network connections were compared between genotype and sex groups. Results: The rs1699102 polymorphism moderated the effects of sex on language performance, with the female having reversed language advantages in T carriers. The T allele carriers had lower gray matter volume in the left precentral gyrus. The effect of sex on language network connections was moderated by rs1699102; male CC homozygotes and female T carriers had higher internetwork connections, which were negatively correlated with language performance. Conclusion: These results suggest that SORL1 moderates the effects of sex on language, with T being a risk allele, especially in females. Our findings underscore the importance of considering the influence of genetic factors when examining sex effects. [ABSTRACT FROM AUTHOR]

External prestressing technology has been widely applied to mitigate the cracking and deflection of variable cross-section continuous box-girder bridges. However, it remains a challenging task to establish a reliable safety monitoring and evaluation method in engineering applications. This paper takes a practical project as the research background and installs a sensing monitoring system on a bridge before strengthening. The evolutions of the strain at the characteristic sections, crack width, and deflection of bridges before and after strengthening were compared and analyzed. The construction process's safety and strengthening measures' effectiveness were monitored and evaluated. According to the construction process monitoring, the prestress tensioning process did not bring torsion to the bridge, and the strain at each monitoring point was within safe boundaries. After strengthening, the bridge appeared to camber with a value of 3–6 mm. The typical cracks were mitigated to different extents, and the closure degree of the crack width was (2.5–4)×10−2 mm. The strain distribution of the bridge was more stable after strengthening, and the frequency of large strain was significantly reduced, which reflected the improvement of section stiffness. The study can provide meaningful references for the optimization design and strengthening strategies of similar projects. [ABSTRACT FROM AUTHOR]

The A/T/N research framework has been proposed for the diagnosis and prognosis of Alzheimer's disease (AD). However, the spatial distribution of ATN biomarkers and their relationship with cognitive impairment and neuropsychiatric symptoms (NPS) need further clarification in patients with AD. We scanned 83 AD patients and 38 cognitively normal controls who independently completed the mini‐mental state examination and Neuropsychiatric Inventory scales. Tau, Aβ, and hypometabolism spatial patterns were characterized using Statistical Parametric Mapping together with [18F]flortaucipir, [18F]florbetapir, and [18F]FDG positron emission tomography. Piecewise linear regression, two‐sample t‐tests, and support vector machine algorithms were used to explore the relationship between tau, Aβ, and hypometabolism and cognition, NPS, and AD diagnosis. The results showed that regions with tau deposition are region‐specific and mainly occurred in inferior temporal lobes in AD, which extensively overlaps with the hypometabolic regions. While the deposition regions of Aβ were unique and the regions affected by hypometabolism were widely distributed. Unlike Aβ, tau and hypometabolism build up monotonically with increasing cognitive impairment in the late stages of AD. In addition, NPS in AD were associated with tau deposition closely, followed by hypometabolism, but not with Aβ. Finally, hypometabolism and tau had higher accuracy in differentiating the AD patients from controls (accuracy = 0.88, accuracy = 0.85) than Aβ (accuracy = 0.81), and the combined three were the highest (accuracy = 0.95). These findings suggest tau pathology is superior over Aβ and glucose metabolism to identify cognitive impairment and NPS. Its results support tau accumulation can be used as a biomarker of clinical impairment in AD. [ABSTRACT FROM AUTHOR]

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To solve the problem of insufficient transverse connection of T-girder bridges, this paper investigated the strengthening method of two composite trusses symmetrically installed in mid-span. The composite truss included two top plates, four diagonal braces, and one horizontal brace. An experimental investigation was carried out to study the mechanical properties of reinforced concrete T-girder using single-point loading method under four load cases. The experimental results showed that the maximum transverse stiffness of T-girder specimens strengthened with composite trusses improved by 12.4% compared with control beams. Simultaneously, it had an excellent restraining effect on the cracks development. The maximum percentage decrease in the deflection corresponding to the maximum load when the reinforced concrete T-girder strengthened with composite trusses over the control beam of up to 39.7 was observed. In addition, the load transverse distribution coefficient was investigated according to rigid-jointed slab (girder) method. The composite trusses were chosen as intermediate diaphragm to calculate moment of inertia. The analytical model was in an accurate with the experimental result under the same loading condition. The optimize spacing of composite trusses was given from 600 mm (L /10) to 1200 mm (L /5), and thickness of top plate was 30 mm when the load transverse distribution coefficient was homogeneously distributed. Finally, a three-dimensional finite element model was used to evaluate the effectiveness of composite trusses. [ABSTRACT FROM AUTHOR]

Increased amyloid burden and decreased glucose metabolism are important characteristics of Alzheimer's disease (AD), but their spatial distribution and hierarchical clustering organization are still poorly understood. In this study, we explored the distribution and clustering organization of amyloid and glucose metabolism based on 18F-florbetapir and 18F-fluorodeoxyglucose PET data from 68 AD patients and 20 cognitively normal individuals. We found that: (i) cortical regions with highest florbetapir binding were the regions with high glucose metabolism; (ii) the percentage changes of amyloid deposition were greatest in the frontal and temporal areas, and the hypometabolism was greatest in the parietal and temporal areas; (iii) brain areas can be divided into three hierarchical clusters by amyloid and into five clusters by metabolism using a hierarchical clustering approach, indicating that adjacent regions are more likely to be grouped into one sub-network; and (iv) there was a significant positive correlation in any pair of amyloid-amyloid and metabolism-metabolism sub-networks, and a significant negative correlation in amyloid-metabolism sub-networks. This may suggest that the influence forms and brain regions of AD on different pathological markers may not be synchronous, but they are closely related. [ABSTRACT FROM AUTHOR]

Video surveillance systems have been widely deployed in public places such as shopping malls, hospitals, banks, and streets to improve the safety of public life and assets. In most cases, how to detect video abnormal events in a timely and accurate manner is the main goal of social public safety risk prevention and control. Due to the ambiguity of anomaly definition, the scarcity of anomalous data, as well as the complex environmental background and human behavior, video anomaly detection is a major problem in the field of computer vision. Existing anomaly detection methods based on deep learning often use trained networks to extract features. These methods are based on existing network structures, instead of designing networks for the goal of anomaly detection. This paper proposed a method based on Deep Support Vector Data Description (DSVDD). By learning a deep neural network, the input normal sample space can be mapped to the smallest hypersphere. Through DSVDD, not only can the smallest size data hypersphere be found to establish SVDD but also useful data feature representations and normal models can be learned. In the test, the samples mapped inside the hypersphere are judged as normal, while the samples mapped outside the hypersphere are judged as abnormal. The proposed method achieves 86.84% and 73.2% frame-level AUC on the CUHK Avenue and ShanghaiTech Campus datasets, respectively. By comparison, the detection results achieved by the proposed method are better than those achieved by the existing state-of-the-art methods. [ABSTRACT FROM AUTHOR]

Background: Lobar cerebral microbleeds (CMBs), which can impair white matter (WM), are often concomitant with definite Alzheimer's disease (AD).Objective: To explore the features of cognitive impairments and WM disruptions due to lobar CMBs in patients with AD.Methods: There were 310 participants who underwent Florbetapir F18 (AV45) amyloid PET and susceptibility-weighted imaging. Participants with cognitive impairment and amyloid-β positive (ADCI) were included into three groups: ADCI without CMBs, with strictly lobar CMBs (SL-CMBs), and with mixed CMBs (M-CMBs). Tract-based spatial statistics were performed to detect the group differences in WM integrity.Results: There were 82 patients and 29 healthy controls finally included. A decreasing tendency in memory and executive performance can be found among HCs > no CMBs (n = 16) >SL-CMBs (n = 41) >M-CMBs (n = 25) group. Compared to no CMBs, M-CMBs group had significantly decreased fractional anisotropy in left anterior thalamic radiation (ATR), forceps major, forceps minor and inferior longitudinal fasciculus, bilateral inferior fronto-occipital fasciculus (IFOF), and superior longitudinal fasciculus. M-CMBs group also had lower fractional anisotropy in left ATR, IFOF, uncinate fasciculus, and forceps minor compared with SL-CMBs. Furthermore, analysis of Pearson correlation indicated damages in discrepant WMs were positively associated with impairment of memory, executive function, and attention.Conclusion: This study showed lobar CMBs had intensively aggravated cognitive impairments associated with extensive WM damages in definite AD. These findings highlight that lobar CMBs play an important role in AD progression and need to be taken into consideration for the early detection of AD. [ABSTRACT FROM AUTHOR]

Background and purpose: The anterior and posterior hippocampal networks represent verbal and spatial memory, respectively, and may play different roles in the pathological mechanism of amnestic mild cognitive impairment (aMCI) and non‐amnestic MCI (naMCI), which has not been explored. Methods: A total of 990 older adults with 791 normal controls (NCs) (65 ± 6 years, 502 women), 140 aMCI (66 ± 7 years, 84 women) and 59 naMCI (66 ± 7 years, 38 women) were included. A multivariate method, partial least squares, was used to assess the structural covariance networks of the anterior hippocampus (aHC) and posterior hippocampus (pHC), and their relationships with verbal memory and spatial memory in the three groups. Results: Three aHC and pHC structural covariance network patterns emerged: (1) the age pattern; (2) the specific aMCI pattern; and (3) the spatial memory pattern. Furthermore, aMCI patients had more extensive and severe damage in the three patterns, and correlated with greater decline in verbal memory, which was mainly characterized by the aHC network. Conclusions: The aMCI and naMCI showed different patterns and damage in the structural covariance networks, and functional segregation of the aHC and pHC networks still exists in the process of pathological aging. A potential neural explanation is provided for the conversion of aMCI and naMCI into different types of dementia in the future. [ABSTRACT FROM AUTHOR]

As for the concrete cracks with complex noise such as honeycomb pockmarks on the surface, a high anti-noise extraction method of concrete cracks based on a dynamic threshold was proposed. Firstly, the noise was weakened and removed by gray-scale transformation, Gaussian filtering, ad information enhancement. The brightness of the crack in the image was enhanced, and the contrast between the crack and the background was improved. Then, the OTSU threshold segmentation algorithm was used to remove the pseudo cracks. Based on the difference between the area of cracks and that of interference noise, the dynamic threshold was introduced to realize the extraction of all kinds of cracks. Finally, based on edge detection and crack skeleton refinement, three characteristic paameters including the crack length, the width and the area were calculated. The results of four groups of crack images taken from the laboratory experiments and the actual bridge show that the average widths were 2.01, 1.07, 1.34 and 0.97 mm, respectively, proving that the proposed method is suitable for the crack extraction of various types under different backgrounds and has strong robustness. [ABSTRACT FROM AUTHOR]

Facing considerable challenges associated with aging and dementia, China urgently needs an evidence‐based health‐care system for prevention and management of dementia. The Beijing Aging Brain Rejuvenation Initiative (BABRI) is a community‐based cohort study initiated in 2008 that focuses on asymptomatic stages of dementia, aims to develop community‐based prevention strategies for cognitive impairment, and provides a platform for scientific research and clinical trials. Thus far, BABRI has recruited 10,255 participants (aged 50 and over, 60.3% female), 2021 of whom have been followed up at least once at a 2‐ or 3‐year interval. This article presents aims and study design of BABRI; summarizes preliminary behavioral and neuroimaging findings on mild cognitive impairment (MCI) and results of clinical trials on MCI; and discusses issues concerning early prevention in community, MCI diagnosis methods, and applications of database of aging and dementia. BABRI is proposed to build a systematic framework on brain health in old age. [ABSTRACT FROM AUTHOR]

Background: Weight loss in late life is associated with a higher risk of dementia and higher mortality. However, the temporal and etiological associations between weight loss and mild cognitive impairment (MCI) remain unclear. Method: We examined 709 Alzheimer's Disease Neuroimaging Initiative participants to investigate body mass index (BMI) trajectories preceding the progression from normal cognition to MCI (N‐t‐M progression), and to explore the association between brain pathology and BMI trajectories preceding incident MCI. Result: During N‐t‐M progression, participants developed multiple brain pathologies, and amyloid β (Aβ) accumulation in the frontotemporal region at baseline was associated with decreased BMI (Figure 1, false discovery rate‐corrected p<0.05). For pathological changes, participants had increased accumulation of Aβ and tau, accelerated hypometabolism, and decreased gray matter volume in the brain during N‐t‐M progression. More importantly, accelerated hypometabolism (p<0.001) and gray matter atrophy (p = 0.011) were associated with a rapid decline in BMI during N‐t‐M progression. Conclusion: These findings highlight the importance of regular monitoring of weight changes in older adults as faster BMI decline and lower BMI may be the result of brain pathology and associated with rapid progression of pathology, and provide a theoretical basis for strategies to minimize weight loss to prevent or delay MCI onset. [ABSTRACT FROM AUTHOR]

Purpose: Brain 18F-fluorodeoxyglucose positron emission tomography (FDG PET) is a sensitive technique for assisting in the diagnosis of patients with anti-leucine-rich glioma-inactivated 1 (LGI1) antibody encephalitis. However, the common pattern of this disorder assessed by FDG PET remains unknown. The present study aimed to explore the glucose metabolic patterns of this disorder based on PET voxel analysis. Methods: This retrospective study enrolled 25 patients with anti-LGI1 encephalitis, who were admitted in Beijing Tiantan Hospital between September 2014 and July 2019. The glucose metabolic pattern was compared between the included patients and 44 age- and gender-matched healthy controls using Statistical Parametric Mapping. Then, the correlation between the metabolic pattern and scaled activities of daily living (ADLs) of the patients was assessed. Results: The median time from symptom onset to PET scans was 9 w (range:2-53w). The groupwise analysis revealed that patients with anti-LGI1 encephalitis had left hippocampal hypermetabolism and hypometabolism in almost all neocortical regions. The individual-level results showed most patients presented a decreased metabolism in neocortical regions, as well as an increase in metabolism in the hippocampus and basal ganglia. Furthermore, the metabolic gradient between hippocampus and neocortical regions was positively associated with the ADLs (frontal lobe, r=0.529, P=0.008; parietal lobe, r=0.474, P=0.019; occipital lobe, r=0.413, P=0.045; temporal lobe, r=0.490, P=0.015), respectively. In addition, the patients with facio-brachial dystonic seizures (FBDS) presented bilateral putamen hypermetabolism, when compared to patients without FBDS and healthy controls. Conclusion: Subcortical hypermetabolism associated with cortical hypometabolism presented with a common metabolic pattern in patients with anti-LGI1 encephalitis in the present study. The resolution of the metabolic gradient of the hippocampal hypermetabolism and neocortical hypometabolism may bring about improved clinical neurologic disability. [ABSTRACT FROM AUTHOR]

Objective: The objective of the study was to explore patterns of white matter (WM) alteration in preclinical stage familial Creutzfeldt–Jakob disease (fCJD) using diffusion tensor imaging (DTI). Methods: Seven asymptomatic carriers of the PRNP G114V mutation and six non-carriers were recruited from the same fCJD kindred and follow-up obtained from all asymptomatic carriers and two non-carriers 2 years later. Overlapping WM patterns were also explored in asymptomatic carriers and symptomatic CJD patients. All participants underwent clinical and neuropsychological assessments and DTI at baseline and follow-up. DTI data were subjected to whole-brain voxel-wise analysis of fractional anisotropy (FA) and mean diffusivity (MD) in WM using tract-based spatial statistics. Three comparisons were conducted: baseline carriers against non-carriers (baseline analysis), changes after 2 years in carriers (follow-up analysis), and differences between patients with symptomatic CJD and healthy controls (CJD patient analysis). Results: Neither carriers nor non-carriers developed any neurological symptoms during 2 years of follow-up. Baseline analysis showed no differences between the carrier and non-carrier groups in MD and FA. Follow-up analysis showed significantly increased MD in multiple WM tracts, among which increased MD in the bilateral superior longitudinal fasciculus, bilateral anterior thalamic radiation, bilateral cingulate gyrus, and left uncinate fasciculus overlapped the patterns observed in patients with symptomatic CJD. Conclusion: Changes in integrity within multiple WM tracts can be detected during the preclinical stage of fCJD. [ABSTRACT FROM AUTHOR]

Background: Pathologic processes in Creutzfeldt-Jakob disease (CJD) are not fully understood. Familial CJD (fCJD) gives opportunities to discover pathologic changes in the preclinical stage.Objective: To investigate cerebral glucose metabolism in the preclinical stage via 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET) in fCJD.Methods: Seven asymptomatic carriers of G114V mutation and six family members without PRNP mutation from the same fCJD kindred were included, and were followed for 2 years. Ten symptomatic CJD patients were also recruited. All subjects underwent standardized clinical examinations and 18F-FDG PET scans. Results were compared in three groups: baseline carriers against non-carriers (baseline analysis), changes after 2 years in carriers (follow-up analysis), and differences between symptomatic CJD patients and healthy controls (CJD patients analysis).Results: No carriers developed any neurological symptoms during 2-year follow-up. Baseline analysis: carriers demonstrates decreased metabolism (p < 0.001) in left and right postcentral, left fusiform, left superior temporal, left lingual, left superior parietal, and left Heschl gyrus. Follow-up analysis shows metabolic decline (p < 0.001) in right inferior temporal, left supra-marginal and left postcentral lobe, and increased metabolism (p < 0.001) in left fusiform, left angular, left thalamus, left Heschl's, right Rolandic operculum, and left superior parietal gyrus. CJD patients demonstrates decreased metabolism in right inferior triangularis frontal gyrus, right middle occipital gyrus, right putamen, right thalamus, and right middle temporal gyrus.Conclusion: Hypo-metabolism of parietal and temporal lobe can be detected by 18F-FDG PET in the preclinical stage of CJD. Subcortical area might compensate in the preclinical stage and decompensate in the symptomatic stage. [ABSTRACT FROM AUTHOR]

Patients with type 2 diabetes mellitus (T2DM) have a considerably high risk of developing dementia, especially for those with mild cognitive impairment (MCI). The investigation of the microstructural change of white matter (WM) between T2DM with amnesic MCI (T2DM-aMCI) and T2DM with normal cognition (T2DM-NC) and their relationships to cognitive performances can help to understand the brain variations in T2DM-related amnesic cognitive impairment. In the current study, 36 T2DM-aMCI patients, 40 T2DM-NC patients, and 40 healthy control (HC) individuals underwent diffusion tensor image and T1-weighted MRI scans and comprehensive cognition assessments. All of these cognitive functions exhibited intergroup ranking differences in patients. The T2DM-NC patients and HC individuals did not reveal any significant differences in WM integrity. The T2DM-aMCI patients showed disrupted integrity in multiple WM tracts compared with HC and T2DM-NC. Specifically, the damaged WM integrity of the right inferior fronto-occipital fasciculus and the right inferior longitudinal fasciculus exhibited significant correlations with episodic memory and attention function impairment in T2DM patients. Furthermore, cognitive impairment-related WM microstructural damage was associated with the degeneration of cortex connected to the affected WM tract. These findings indicate that degeneration exists extensively in WM tracts in T2DM-aMCI, whereas no brain WM damage is evident in T2DM-NC. [ABSTRACT FROM AUTHOR]

Background: Dysfunction of the thalamus has been proposed as a core mechanism of fatal familial insomnia. However, detailed metabolic and structural alterations in thalamic subnuclei are not well documented. We aimed to address the multimodal structuro‐metabolic pattern at the level of the thalamic nuclei in fatal familial insomnia patients, and investigated the clinical presentation of primary thalamic alterations. Method: Five fatal familial insomnia patients and 10 healthy controls were enrolled in this study. All participants underwent neuropsychological assessments, polysomnography, electroencephalogram, and cerebrospinal fluid tests. MRI and fluorodeoxyglucose PET were acquired on a hybrid PET/MRI system. Structural and metabolic changes were compared using voxel‐based morphometry analyses and standardized uptake value ratio analyses, focusing on thalamic subnuclei region of interest analyses. Correlation analysis was conducted between gray matter volume and metabolic decrease ratios, and clinical features. Result: The whole‐brain analysis showed that gray matter volume decline was confined to the bilateral thalamus and right middle temporal pole in fatal familial insomnia patients, whereas hypometabolism was observed in the bilateral thalamus, basal ganglia, and widespread cortices, mainly in the forebrain. In the regions of interest analysis, gray matter volume and metabolism decreases were prominent in bilateral medial dorsal nuclei, anterior nuclei, and the pulvinar, which is consistent with neuropathological and clinical findings. A positive correlation was found between gray matter volume and metabolic decrease ratios. Conclusion: Our study revealed specific structuro‐metabolic pattern of fatal familial insomnia that demonstrated the essential roles of medial dorsal nuclei, anterior nuclei, and pulvinar, which may be a potential biomarker in diagnosis. Also, primary thalamic subnuclei alterations may be correlated with insomnia, neuropsychiatric, and autonomic symptoms sparing primary cortical involvement. [ABSTRACT FROM AUTHOR]

To investigate the alterations of basal ganglia (BG)-cortical structural and functional connectivity induced by subcortical silent lacunar infarct (SLI), and their associations with cognitive impairment in SLI subjects. All participants were recruited from communities, including 30 subcortical SLIs and 30 age-, gender-, and education-matched healthy controls. The structural and functional connectivity of BG-cortical circuits using diffusion and resting-state functional magnetic resonance imaging data were obtained. Diffusion abnormalities of the white matter tracts connecting the BG and cortical areas were observed in SLI subjects, including the BG-lateral frontal, BG-orbital frontal, and BG-insula tracts. Multiple regions showed a reduced BG-cortical functional connectivity in SLI patients, including direct connectivities with the BG, such as the BG-limbic, BG-insula, and BG-frontal connectivities, and others that showed no direct causation with the BG, such as the insula-limbic, insula-parietal, and frontal-parietal connectivities. Coupling of structural and functional BG-cortical connectivity was observed in healthy controls but not in SLI patients. Significant correlations between structural and functional BG-cortical connectivity and cognitive performance were demonstrated in SLI patients, indicating the potential use of BG-cortical connectivities as MRI biomarkers to assess cognitive impairment. These findings suggest that subcortical SLIs can impair BG-cortical circuits, and these changes may be the pathological basis of cognitive impairment in SLI patients. [ABSTRACT FROM AUTHOR]