To evaluate the incremental diagnostic value of 18F-Flutemetamol PET following MRI measurements on an unselected prospective cohort collected from a memory clinic. A total of 84 participants was included in this study. A stepwise study design was performed including initial analysis (based on clinical assessments), interim analysis (revision of initial analysis post-MRI) and final analysis (revision of interim analysis post-18F-Flutemetamol PET). At each time of evaluation, every participant was categorized into SCD, MCI or dementia syndromal group and further into AD-related, non-AD related or non-specific type etiological subgroup. Post 18F-Flutemetamol PET, the significant changes were seen in the syndromal MCI group (57%, p < 0.001) involving the following etiological subgroups: AD-related MCI (57%, p < 0.01) and non-specific MCI (100%, p < 0.0001); and syndromal dementia group (61%, p < 0.0001) consisting of non-specific dementia subgroup (100%, p < 0.0001). In the binary regression model, amyloid status significantly influenced the diagnostic results of interim analysis (p < 0.01). 18F-Flutemetamol PET can have incremental value following MRI measurements, particularly reflected in the change of diagnosis of individuals with unclear etiology and AD-related-suspected patients due to the role in complementing AD-related pathological information.

Despite well-known systemic immune reactions in peripheral trauma, little is known about their roles in posttraumatic neurological disorders, such as anxiety, sickness, and cognitive impairment. Leukocyte invasion of the brain, a common denominator of systemic inflammation, is involved in neurological disorders that occur in peripheral inflammatory diseases, whereas the influences of peripheral leukocytes on the brain after peripheral trauma remain largely unclear. In this study, we found that leukocytes, largely macrophages, transiently invaded the brain of zebrafish larvae after peripheral trauma through vasculature-independent migration, which was a part of the systemic inflammation and was mediated by interleukin-1b (il1b). Notably, myeloid cells in the brain that consist of microglia and invading macrophages were implicated in posttraumatic anxiety-like behaviors, such as hyperactivity (restlessness) and thigmotaxis (avoidance), while a reduction in systemic inflammation or myeloid cells can rescue these behaviors. In addition, invading leukocytes together with microglia were found to be responsible for the clearance of apoptotic cells in the brain; however, they also removed the nonapoptotic cells, which suggested that phagocytes have dual roles in the brain after peripheral trauma. More importantly, a category of conserved proteins between zebrafish and humans or rodents that has been featured in systemic inflammation and neurological disorders was determined in the zebrafish brain after peripheral trauma, which supported that zebrafish is a translational model of posttraumatic neurological disorders. These findings depicted leukocyte invasion of the brain during systemic inflammation after peripheral trauma and its influences on the brain through il1b-dependent mechanisms.

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Background: Notwithstanding successful aging being a multidimensional construct, measuring successful aging in adults of advanced age, such as nonagenarians and centenarians, has often been challenging. First, over reliance on physical health criteria could be unrealistic, considering most of these older adults are living with multimorbidity and disability. Second, enumerating the number of criteria fulfilled may not reflect the diversity of how they attain (partial) successful aging through soliciting different resources in their daily lives. Hence, this study investigated the subphenotypes of successful aging using the data from Hong Kong Centenarian Study 2 by referencing to two models which have been adopted in previous centenarian studies. Method: Between April 2021 and September 2022, we interviewed the family caregivers of 146 community dwelling older adults aged 95 or above by phone. A structured questionnaire with items on the physical, psychological, and social well-being of the older adults was administered. Latent class analysis was used to identify the classes of successful aging based on eleven dichotomized indicators - good health, happiness, good perceived economic status, absence of dementia diagnosis, ambulation, resistance, indoor transfer, dressing, vision and hearing impairment and weekly social activities. Results: Among the 146 older adults aged between 95 to 106 (mean (SD): 97.5 (2.5); 76.0% female), 13.0% fulfilled all successful aging criteria based on caregivers’ judgments of happiness, health, and economic status, and 2.1% fulfilled all criteria based on caregivers’ observation of their physical functions and social activities. LCA identified three latent classes: Class 1 (46.6%) characterized by poor cognitive and functional health, Class 2 (37.0%) with good functional health but poor mobility, and Class 3 (16.4%) with overall good health. Class membership was unrelated to gender, age, living arrangement, and education status of the older adults. Conclusions: Although we found a relatively low occurrence of successful aging among Hong Kong adults of advanced age, possibly due to the adverse impact of COVID on their physical, psychological, and social well-being, understanding how successful aging was (partially) attained by these long-lived individuals will enable social and health care professionals to encourage late-life productive involvement, especially in the post-COVID era. (349 words)