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Accurate quantification of amyloid positron emission tomography (PET) is essential for early detection of and intervention in Alzheimer's disease (AD) but there is still a lack of studies comparing the performance of various automated methods. This study compared the PET-only method and PET-and-MRI-based method with a pre-trained deep learning segmentation model. A large sample of 1180 participants in the Catholic Aging Brain Imaging (CABI) database was analyzed to calculate the regional standardized uptake value ratio (SUVR) using both methods. The logistic regression models were employed to assess the discriminability of amyloid-positive and negative groups through 10-fold cross-validation and area under the receiver operating characteristics (AUROC) metrics. The two methods showed a high correlation in calculating SUVRs but the PET-MRI method, incorporating MRI data for anatomical accuracy, demonstrated superior performance in predicting amyloid-positivity. The parietal, frontal, and cingulate importantly contributed to the prediction. The PET-MRI method with a pre-trained deep learning model approach provides an efficient and precise method for earlier diagnosis and intervention in the AD continuum. [ABSTRACT FROM AUTHOR]

INTRODUCTION: Despite prior research on the association between sarcopenia and cognitive impairment in the elderly, a comprehensive model that integrates various brain pathologies is still lacking. METHODS: We used data from 528 non‐demented older adults with or without sarcopenia in the Catholic Aging Brain Imaging (CABI) database, containing magnetic resonance imaging scans, positron emission tomography scans, and clinical data. We also measured three key components of sarcopenia: skeletal muscle index (SMI), hand grip strength (HGS), and the five times sit‐to‐stand test (5STS). RESULTS: All components of sarcopenia were significantly correlated with global cognitive function, but cortical thickness and amyloid‐beta (Aβ) retention had distinctive relationships with each measure. In the path model, brain atrophy resulting in cognitive impairment was mediated by Aβ retention for SMI and periventricular white matter hyperintensity for HGS, but directly affected by the 5STS. DISCUSSION: Treatments targeting each sub‐domain of sarcopenia should be considered to prevent cognitive decline. Highlights: We identified distinct impacts of three sarcopenia measures on brain structure and Aβ.Muscle mass is mainly associated with Aβ and has an influence on the brain atrophy.Muscle strength linked with periventricular WMH and brain atrophy.Muscle function associated with cortical thinning in specific brain regions.Interventions on sarcopenia may be important to ease cognitive decline in the elderly. [ABSTRACT FROM AUTHOR]

Exercise has long been recognized as an important component of treatment for various diseases. However, the benefits and risks of exercise interventions must be carefully evaluated to ensure the former outweighs the latter. As cancer patients undergo diverse treatment modalities with distinct objectives, a systematic approach partitioning the cancer journey into distinct phases is necessary to inform tailored exercise prescriptions. This narrative review summarizes exercise benefits and mechanisms for cancer patients and survivors across four distinct survivorship periods--before surgery, after surgery and before adjuvant treatment, during nonsurgical treatment (adjuvant and neoadjuvant), and during extended survival. In summary, exercise reduces the risks of complications and declines in physical functioning while improving fatigue, quality of life, and the ability to manage treatment effects. Although additional research is warranted, existing evidence is sufficient to integrate exercise into clinical oncology practice and cancer survivorship programs. [ABSTRACT FROM AUTHOR]

To provide clear see‐through image quality is one of the most important performances of a transparent display, because of its see‐through capability. Purity is one of the quantitative measure can evaluate the see‐through image quality in terms of perceived blurriness. In this paper, the characteristics of purity are investigated. Experimental results indicate that the purity values have highly correlated with perceptual blurriness of see‐through images. Furthermore, the perceptual limit of purity value is also derived. [ABSTRACT FROM AUTHOR]

Background: Recent interest has surged in the locus coeruleus (LC) for its early involvement in Alzheimer's disease (AD), notably concerning the apolipoprotein ɛ4 allele (APOE4). Objective: This study aimed to discern LC functional connectivity (FC) variations in preclinical AD subjects, dissecting the roles of APOE4 carrier status and amyloid-β (Aβ) deposition. Methods: A cohort of 112 cognitively intact individuals, all Aβ-positive, split into 70 APOE4 noncarriers and 42 carriers, underwent functional MRI scans, neuropsychological assessments, and APOE genotyping. The research utilized seed to voxel analysis for illustrating LC rsFC discrepancies between APOE4 statuses and employed a general linear model to examine the interactive influence of APOE4 carrier status and Aβ deposition on LC FC values. Results: The investigation revealed no significant differences in sex, age, or SUVR between APOE4 carriers and noncarriers. It found diminished LC FC with the occipital cortex in APOE4 carriers and identified a significant interaction between APOE4 carrier status and temporal lobe SUVR in LC FC with the occipital cortex. This interaction suggested a proportional increase in LC FC for APOE4 carriers. Additional notable interactions were observed affecting LC FC with various brain regions, indicating a proportional decrease in LC FC for APOE4 carriers. Conclusions: These findings confirm that APOE4 carrier status significantly influences LC FC in preclinical AD, showcasing an intricate relationship with regional Aβ deposition. This underscores the critical role of genetic and pathological factors in early AD pathophysiology, offering insights into potential biomarkers for early detection and intervention strategies. [ABSTRACT FROM AUTHOR]

Selective herbicides are used to control undesirable vegetation or weeds in fields without harming crops. Herbicide use for weed management can directly impact the densities of insect pests in agricultural communities as a result of insect mortality during and immediately after application. In insects, the glutathione S‐transferase (GST) enzyme is involved in both the detoxification process and the defense of cellular membranes against oxidative damage. In this study, two TmGSTs (TmGST‐iso1 and TmGST‐iso2) were identified and characterized to elucidate the GST family in Tenebrio molitor. Among the developmental stages of T. molitor, eggs had the highest expression levels of TmGST‐iso1. TmGST‐iso2 expression was highest in the pre‐pupal stage. TmGST‐iso1 expression was high in the guts of early and late larvae, whereas TmGST‐iso2 expression was not observed in early larvae. Adults, both male and female, had the highest levels of TmGST‐iso1 mRNA expression in the gut and reproductive organs, and the highest levels of TmGST‐iso2 expression in the reproductive organs. Quantitative polymerase chain reaction was used to investigate the impact of treatment with butachlor on the mRNA expression of TmGST‐iso1 and TmGST‐iso2 in larvae. TmGST‐iso1 expression increased in the butachlor‐treated group after 3 and 24 h, whereas TmGST‐iso2 expression peaked at 24 h after treatment. This study provides vital information about the detoxifying activities of T. molitor. [ABSTRACT FROM AUTHOR]

Agricultural intensification has led to significant increases in production, but the overuse of pesticides and associated hazards pose threats to biodiversity and ecological functions. Catalase (CAT), a key antioxidant enzyme, plays a crucial role in alleviating oxidative stress by directly interacting with toxins. In this study, we identified three CAT isoforms in Tenebrio molitor (TmCAT‐iso1, TmCAT‐iso2 and TmCAT‐iso3). These CATs possess a CAT domain, tetramer interface sites and a heme‐binding pocket. We examined the expression of Tm catalases across all developmental stages and in specific tissues using quantitative real time polymerase chain reaction (qRT‐PCR) experiments. Our findings demonstrate that TmCAT‐iso1 and TmCAT‐iso3 exhibit peak expression in young and late larval stages, respectively, whereas TmCAT‐iso2 shows peak expression during the egg and pre‐pupal stages. Tissue distribution analysis revealed the high expression of TmCAT‐iso1 and TmCAT‐iso2 in larval hemocytes, whereas TmCAT‐iso3 is predominantly expressed in larval Malpighian tubules. Furthermore, injection with chlorantraniliprole significantly elevated mRNA expression levels of TmCAT‐iso1, TmCAT‐iso2, and TmCAT‐iso3 in larval groups, compared with control groups. Our study highlights the distinct developmental stages and tissues where TmCATs are expressed. We also elucidated the effects of pesticide application on the expression of each TmCAT, revealing the physiological characteristics of CATs in response to these pesticides, which are dose‐ and time‐dependent in T. molitor. [ABSTRACT FROM AUTHOR]

Background: Brain volume is associated with cognitive decline in later life, and cortical brain atrophy exceeding the normal range is related to inferior cognitive and behavioral outcomes in later life. Objective: To investigate the likelihood of cognitive decline, mild cognitive impairment (MCI), or dementia, when regional atrophy is present in participants' magnetic resonance imaging (MRI). Methods: Multi-center MRI data of 2,545 adults were utilized to measure regional volumes using NEUROPHET AQUA. Four lobes (frontal, parietal, temporal, and occipital), four Alzheimer's disease-related regions (entorhinal, fusiform, inferior temporal, and middle temporal area), and the hippocampus in the left and right hemispheres were measured and analyzed. The presence of regional atrophy from brain MRI was defined as ≤1.5 standard deviation (SD) compared to the age- and sex-matched cognitively normal population. The risk ratio for cognitive decline was investigated for participants with regional atrophy in contrast to those without regional atrophy. Results: The risk ratio for cognitive decline was significantly higher when hippocampal atrophy was present (MCI, 1.84, p < 0.001; dementia, 4.17, p < 0.001). Additionally, participants with joint atrophy in multiple regions showed a higher risk ratio for dementia, e.g., 9.6 risk ratio (95% confidence interval, 8.0–11.5), with atrophy identified in the frontal, temporal, and hippocampal gray matter, than those without atrophy. Conclusions: Our study showed that individuals with multiple regional atrophy (either lobar or AD-specific regions) have a higher likelihood of developing dementia compared to the age- and sex-matched population without atrophy. Thus, further consideration is needed when assessing MRI findings. [ABSTRACT FROM AUTHOR]