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The prevalence of Alzheimer's disease (AD) is increasing globally due to population aging. However, effective clinical treatment strategies for AD still remain elusive. The mechanisms underlying AD onset and the interplay between its pathological factors have so far been unclear. Evidence indicates that AD progression is ultimately driven by neuronal loss, which in turn is caused by neuroapoptosis and neuroinflammation. Therefore, the inhibition of neuroapoptosis and neuroinflammation could be a useful anti-AD strategy. Nonetheless, the delivery of active drug agents into the brain parenchyma is hindered by the blood-brain barrier (BBB). To address this challenge, we fabricated a black phosphorus nanosheet (BP)-based methylene blue (MB) delivery system (BP-MB) for AD therapy. After confirming the successful preparation of BP-MB, we proved that its BBB-crossing ability was enhanced under near-infrared light irradiation. In vitro pharmacodynamics analysis revealed that BP and MB could synergistically scavenge excessive reactive oxygen species (ROS) in okadaic acid (OA)-treated PC12 cells and lipopolysaccharide (LPS)-treated BV2 cells, thus efficiently reversing neuroapoptosis and neuroinflammation. To study in vivo pharmacodynamics, we established a mouse model of AD mice, and behavioral tests confirmed that BP-MB treatment could successfully improve cognitive function in these animals. Notably, the results of pathological evaluation were consistent with those of the in vitro assays. The findings demonstrated that BP-MB could scavenge excessive ROS and inhibit Tau hyperphosphorylation, thereby alleviating downstream neuroapoptosis and regulating the polarization of microglia from the pro-inflammatory M1 phenotype to the anti-inflammatory M2 phenotype. Overall, this study highlights the therapeutic potential of a smart nanomedicine with the capability of reversing neuroapoptosis and neuroinflammation for AD treatment.

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BACKGROUND: In Alzheimer's disease (AD) diagnosis, a cerebrospinal fluid (CSF) biomarker panel is commonly interpreted with binary cutoff values. However, these values are not generic and do not reflect the disease continuum. We explored the use of interval-specific likelihood ratios (LRs) and probability-based models for AD using a CSF biomarker panel. METHODS: CSF biomarker (Aß1-42, tTau and pTau181) data for both a clinical discovery cohort of 241 patients (measured with INNOTEST) and a clinical validation cohort of 129 patients (measured with EUROIMMUN), both including AD and non-AD dementia/cognitive complaints were retrospectively retrieved in a single-center study. Interval-specific LRs for AD were calculated and validated for univariate and combined (Aß1-42/tTau and pTau181) biomarkers, and a continuous bivariate probability-based model for AD, plotting Aß1-42/tTau versus pTau181 was constructed and validated. RESULTS: LR for AD increased as individual CSF biomarker values deviated from normal. Interval-specific LRs of a combined biomarker model showed that once one biomarker became abnormal, LRs increased even further when another biomarker largely deviated from normal, as replicated in the validation cohort. A bivariate probability-based model predicted AD with a validated accuracy of 88% on a continuous scale. CONCLUSIONS: Interval-specific LRs in a combined biomarker model and prediction of AD using a continuous bivariate biomarker probability-based model, offer a more meaningful interpretation of CSF AD biomarkers on a (semi-)continuous scale with respect to the post-test probability of AD across different assays and cohorts.

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The population experiencing Alzheimer's disease (AD) and their caregivers have been tremendously impacted by the global COVID-19 pandemic. Outpatient services became less accessible during the pandemic lockdown which caused increased caregiver burden more than usual. Further examination discovered that caregivers were unable to properly take care of themselves because of the need to provide around-the-clock care to loved ones, who pre-pandemic were able to receive supplemental caregiving services. The purpose of this integrative review was to provide a synthesis of information regarding caregiver experiences, during a time of limited resources, such as with the COVID-19 global pandemic. A comprehensive search of the literature databases Cumulative Index to Nursing and Allied Health Literature (CINAHL) and Medline was completed yielding qualitative and mixed-methods studies. The literature search yielded 14 articles which met the criteria. Three themes emerged during this review. They include: Deprivation of self-care and social connectedness, Fragmented care and resources, and Improved policy development. Multiple gaps in caregiver needs have been identified throughout the literature. Outpatient services, home health aides, and respite care remain necessary elements of care for those with AD and for the relief of the caregiver. Forward planning should include government policies to support caregiving of those with AD, especially in the light of service restrictions or unavailable services.

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The launch of lecanemab (an anti-Aß antibody) has introduced a new treatment for Alzheimer's disease. In contrast to conventional therapeutic approaches to dementia, this drug requires new concepts in diagnosis, evaluation, and adverse effects. Specifically, evaluation of the efficacy of lecanemab is extremely important because this drug does not prevent but only slows the rate of disease progression. In this report, I have discussed future issues, including my personal viewpoint and also described the guidelines for promotion of the optimal use of lecanemab issued by the Ministry of Health, Labour, and Welfare.

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Amyloid-related imaging abnormalities (ARIA) represent the most frequent adverse effect of lecanemab, a monoclonal antibody drug that targets amyloid beta. ARIA is observed in approximately 20% of patients who receive lecanemab. Most patients are asymptomatic; however, some develop serious neurological symptoms, and optimal management remains clinically challenging in such cases. In this review, I summarize the pathomechanism underlying ARIA and associated disorders, in addition to countermeasures for ARIA.

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Amyloid PET plays a crucial role in the early diagnosis of Alzheimer's disease and the determination of the feasibility of disease-modifying therapies. It offers several advantages, including high sensitivity and specificity, minimal invasiveness, and the ability to provide spatial evaluation, all of which contribute to the optimization of dementia care. However, proper use and interpretation of the results require a thorough understanding of their limitations. Although careful consideration is necessary when using scans on asymptomatic individuals, clinical applications could broaden if preemptive treatments and high-precision individual risk assessments for the preclinical stage are developed.

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Tau positron emission tomography (PET) is a neuroimaging technique that visualizes tau deposition using PET tracers that selectively bind to tau aggregates. Studies have reported the diagnostic and prognostic value of tau PET in Alzheimer's disease and other tauopathies. However, the binding profiles of tau PET drugs vary widely across tauopathies; therefore, an accurate understanding of the disease-specific characteristics is essential for interpretation of tau PET findings. In this review, we discuss the properties of tau-PET agents and their applications in various diseases.

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Alzheimer's disease (AD) is a common dementia disorder in the elderly individuals, accounting for approximately 60-70% of all dementia cases. Recently, significant progress has been made in developing and approving anti-amyloid antibody drugs as one of the disease-modifying therapies (DMT) that aim to slow the progression of AD by targeting amyloid-beta accumulation in the brain. Notable drugs such as aducanumab, lecanemab, and donanemab have shown potential in clinical trials, leading to the approval of aducanumab and lecanemab, and approval is also expected for donanemab. Other anti-amyloid drugs such as remternetug and trontinemab are also under development. However, challenges remain, including adverse effects like amyloid-related imaging abnormalities (ARIA) and the need for addressing healthcare preparedness to support their use. This paper outlines the current status of DMT for AD, including the clinical trial results and current applications of these drugs. It also discusses the existing challenges to improve the safety and accessibility of DMTs.

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Blood biomarkers are minimally invasive, are available at a relatively low cost, and are easily accessible; therefore, they are expected to play a pivotal role in the diagnosis of dementia. Measurement of the amyloid-ß ratio and phosphorylated tau in plasma has shown high potential for accurate detection of brain pathology in patients with Alzheimer's disease. Studies have investigated blood biomarkers that reflect neurodegeneration and neuroinflammation in patients with dementia. Challenges associated with blood biomarker use include the lack of robustness of the test and the role of confounders that potentially prevent their immediate clinical application. Further real-world studies are warranted to validate the usefulness of blood biomarkers in dementia management. Appropriate recommendations for the use of blood biomarkers for dementia have been published for physicians and investigators, both in Japan and overseas. Considering the versatility of blood biomarkers, they should be cautiously introduced for clinical use.

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The molecular pathogenesis of Alzheimer's disease (AD) has been elucidated through the biochemical analysis of senile plaques, neurofibrillary tangles, and pathological features of the brains of patients with AD. Genetic analysis, initiated with familial AD investigation, has revealed that Aß aggregation and accumulation are crucial processes in AD pathogenesis. The success of lecanemab against aggregated Aß is the result of these efforts. Meanwhile, research on tau as a causative molecule in AD and various other tauopathies is advancing gradually. Furthermore, genetic analysis has revealed that the inflammatory response of glial cells modifies AD pathophysiology; a novel therapeutic strategy for inflammation control is thus currently under consideration. This article summarizes the latest discoveries related to these new therapeutic strategies for AD.

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Conventionally, APOE genetic testing has not been recommended as a component of the standard diagnostic and management practices for Alzheimer's disease. However, recent research highlights the importance of this test, particularly for assessment of the safety profile of anti-amyloid-ß therapies. Therefore, the current United States guidelines for the administration of lecanemab explicitly advise APOE genetic testing. However, integration of this testing into clinical practice is associated with many clinical, ethical, legal, and economic challenges. It is important to initiate comprehensive discussions to address these multifaceted issues in Japan.

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ABSTRACT: Communication is an essential aspect of care for all patients but is especially important for individuals with Alzheimer's disease or other forms of dementia. Nurses who care for persons living with dementia (PwD), as well as family members and caregivers, need understanding of verbal and nonverbal communication techniques and approaches that are effective throughout the stages of dementia. Spiritual assessment and care also are critical. This article provides evidence-based and biblical examples for communication as a healing art in caring for PwD.

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The findings concerning the association between endocannabinoid system (ECS) and Alzheimer's disease (AD) exhibited inconsistencies when examining the expression levels of endocannabinoids. This study aimed to provide a comprehensive summary of the studies regarding alterations of the ECS in AD. Six databases were thoroughly searched for literature to select relevant studies investigating the ECS in AD, including changes in cannabinoid receptors (CB1R and CB2R), endocannabinoids (2-AG and AEA), and their associated enzymes (FAAH and MAGL). Traditional meta-analysis evaluated the expression levels of the ECS in AD, and the results showed no significant differences in ECS components between healthy controls and AD patients. However, subgroup analysis revealed significantly lower expression levels of CB1R in AD than in controls, particularly in studies using western blot (SMD = -0.88, p < 0.01) and in studies testing CB1R of frontal cortex (SMD = -1.09, p < 0.01). For studies using HPLC, the subgroup analysis indicated significantly higher 2-AG levels in AD than in controls (SMD = 0.46, p = 0.02). Network meta-analysis examined the rank of ECS alterations in AD compared to controls, and the findings revealed that 2-AG and MAGL exhibited the largest increase and CB1R showed the largest decrease relative to the control group. Based on the findings of traditional meta-analysis and network meta-analysis, we proposed that AD patients may present decreased expression levels of CB1R and increased expression levels of 2-AG and its degrading enzyme MAGL. Our results may contribute to the growing body of research supporting the therapeutic potential of ECS modulation in the management of AD.

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Alzheimer's disease (AD), characterized by cognitive impairment, brain plaques, and tangles, is a global health concern affecting millions. It involves the build-up of amyloid-ß (Aß) and tau proteins, the formation of neuritic plaques and neurofibrillary tangles, cholinergic system dysfunction, genetic variations, and mitochondrial dysfunction. Various signaling pathways and metabolic processes are implicated in AD, along with numerous biomarkers used for diagnosis, risk assessment, and research. Despite these, there is no cure or effective treatment for AD. It is critically important to address this immediately to develop novel drug delivery systems (NDDS) capable of targeting the brain and delivering therapeutic agents to modulate the pathological processes of AD. This review summarizes AD, its pathogenesis, related signaling pathways, biomarkers, conventional treatments, the need for NDDS, and their application in AD treatment. It also covers preclinical, clinical, and ongoing trials, patents, and marketed AD formulations.

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Individual health data is crucial for scientific advancements, particularly in developing Artificial Intelligence (AI); however, sharing real patient information is often restricted due to privacy concerns. A promising solution to this challenge is synthetic data generation. This technique creates entirely new datasets that mimic the statistical properties of real data, while preserving confidential patient information. In this paper, we present the workflow and different services developed in the context of Germany's National Data Infrastructure project NFDI4Health. First, two state-of-the-art AI tools (namely, VAMBN and MultiNODEs) for generating synthetic health data are outlined. Further, we introduce SYNDAT (a public web-based tool) which allows users to visualize and assess the quality and risk of synthetic data provided by desired generative models. Additionally, the utility of the proposed methods and the web-based tool is showcased using data from Alzheimer's Disease Neuroimaging Initiative (ADNI) and the Center for Cancer Registry Data of the Robert Koch Institute (RKI).

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Alzheimer's disease (AD) is a brain illness that causes gradual memory loss. AD has no treatment and cannot be cured, so early detection is critical. Various AD diagnosis approaches are used in this regard, but Magnetic Resonance Imaging (MRI) provides the most helpful neuroimaging tool for detecting AD. In this paper, we employ a DenseNet-201 based transfer learning technique for diagnosing different Alzheimer's stages as Non-Demented (ND), Moderate Demented (MOD), Mild Demented (MD), Very Mild Demented (VMD), and Severe Demented (SD). The suggested method for a dataset of MRI scans for Alzheimer's disease is divided into five classes. Data augmentation methods were used to expand the size of the dataset and increase DenseNet-201's accuracy. It was found that the proposed strategy provides a very high classification accuracy. This practical and reliable model delivers a success rate of 98.24%. The findings of the experiments demonstrate that the suggested deep learning approach is more accurate and performs well compared to existing techniques and state-of-the-art methods.

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BACKGROUND: Synaptic dysfunction, characterized by synapse loss and structural alterations, emerges as a prominent correlate of cognitive decline in Alzheimer's disease (AD). Actin cytoskeleton, which serves as the structural backbone of synaptic architecture, is observed to be lost from synapses in AD. Actin cytoskeleton loss compromises synaptic integrity, affecting glutamatergic receptor levels, neurotransmission, and synaptic strength. Understanding these molecular changes is crucial for developing interventions targeting synaptic dysfunction, potentially mitigating cognitive decline in AD. METHODS: In this study, we investigated the synaptic actin interactome using mass spectrometry in a mouse model of AD, APP/PS1. Our objective was to explore how alterations in synaptic actin dynamics, particularly the interaction between PSD-95 and actin, contribute to synaptic and cognitive impairment in AD. To assess the impact of restoring F-actin levels on synaptic and cognitive functions in APP/PS1 mice, we administered F-actin stabilizing agent, jasplakinolide. Behavioral deficits in the mice were evaluated using the contextual fear conditioning paradigm. We utilized primary neuronal cultures to study the synaptic levels of AMPA and NMDA receptors and the dynamics of PSD-95 actin association. Furthermore, we analyzed postmortem brain tissue samples from subjects with no cognitive impairment (NCI), mild cognitive impairment (MCI), and Alzheimer's dementia (AD) to determine the association between PSD-95 and actin. RESULTS: We found a significant reduction in PSD-95-actin association in synaptosomes from middle-aged APP/PS1 mice compared to wild-type (WT) mice. Treatment with jasplakinolide, an actin stabilizer, reversed deficits in memory recall, restored PSD-95-actin association, and increased synaptic F-actin levels in APP/PS1 mice. Additionally, actin stabilization led to elevated synaptic levels of AMPA and NMDA receptors, enhanced dendritic spine density, suggesting improved neurotransmission and synaptic strength in primary cortical neurons from APP/PS1 mice. Furthermore, analysis of postmortem human tissue with NCI, MCI and AD subjects revealed disrupted PSD-95-actin interactions, underscoring the clinical relevance of our preclinical studies. CONCLUSION: Our study elucidates disrupted PSD-95 actin interactions across different models, highlighting potential therapeutic targets for AD. Stabilizing F-actin restores synaptic integrity and ameliorates cognitive deficits in APP/PS1 mice, suggesting that targeting synaptic actin regulation could be a promising therapeutic strategy to mitigate cognitive decline in AD.

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The present study aimed to validate the association between core cuproptosis genes (CRGs) and Alzheimer's disease (AD) from both bioinformatics and experimental perspectives and also to develop a risk prediction model. To this end, 78 human­derived temporal back samples were analyzed from GSE109887, and the biological functions of the resulting CRGs were explored by cluster analysis, weighted gene co­expression network analysis and similar methods to identify the best machine model. Moreover, an external dataset GSE33000 and a nomogram were used to validate the model. The mRNA and protein expression of CRGs were validated using the SH­SY5Y cell model and the Sprague­Dawley rat animal model. The RT­qPCR and western blotting results showed that the mRNA and protein expression content of dihydrolipoamide dehydrogenase, ferredoxin 1, glutaminase and pyruvate dehydrogenase E1 subunit ß decreased, and the expression of dihydrolipoamide branched chain transacylase E2 increased in AD, which supported the bioinformatic analysis results. The CRG expression alterations affected the aggregation and infiltration of certain immune cells. The present study also confirmed the accuracy and validity of AD diagnostic models and nomograms, and validated the association between five CRGs and AD, indicating a significant difference between patients with AD and healthy individuals. Therefore, CRGs are expected to serve as relevant biomarkers for the diagnosis and prognostic monitoring of AD.

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Sleep and circadian rhythm dysfunctions are common clinical features of Alzheimer's disease (AD). Increasing evidence suggests that in addition to being a symptom, sleep disturbances can also drive the progression of neurodegeneration. Protein aggregation is a pathological hallmark of AD; however, the molecular pathways behind how sleep affects protein homeostasis remain elusive. Here we demonstrate that sleep modulation influences proteostasis and the progression of neurodegeneration in Drosophila models of tauopathy. We show that sleep deprivation enhanced Tau aggregational toxicity resulting in exacerbated synaptic degeneration. In contrast, sleep induction using gaboxadol led to reduced toxic Tau accumulation in neurons as a result of modulated autophagic flux and enhanced clearance of ubiquitinated Tau, suggesting altered protein processing and clearance that resulted in improved synaptic integrity and function. These findings highlight the complex relationship between sleep and regulation of protein homeostasis and the neuroprotective potential of sleep-enhancing therapeutics to slow the progression or delay the onset of neurodegeneration.

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