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The symptoms of tracheobronchial foreign body in the elderly are not typical, so they are often missed or misdiagnosed. This study aims to depict the clinical characteristics of tracheobronchial foreign body inhalation in the elderly. We retrospectively analysed the clinical data of elder patients (age ≥ 65 years) diagnosed with tracheal and bronchial foreign bodies. The data included age, sex, clinical symptoms, type and location of foreign bodies, prehospital duration, Chest CT, bronchoscopic findings, and frequencies and tools for removing these elderly patients' tracheal and bronchial foreign bodies. All patients were followed up for a half year. Fifty-nine cases were included, of which only 32.2% had a definite aspiration history. Disease duration > 30 days accounted for 27.1% of the patients. 27.1% of the patients had a history of stroke, and 23.8% had Alzheimer's Disease. Regarding clinical symptoms, patients mainly experience cough and expectoration. The most common CT findings were abnormal density shadow (37.3%) and pulmonary infiltration (22.0%). Under bronchoscopy, purulent secretions were observed in 52.5% of patients, and granulation tissue hyperplasia was observed in 45.8%. Food (55.9%) was the most common foreign object, including seafood shells (5.1%), bones (20.3%), dentures (18.6%), and tablets (20.3%). The success rate of foreign body removal under a bronchoscope was 96.7%, 28.8% of the foreign bodies were on the left and 69.5% on the right. 5.1% of the elderly patients required rigid bronchoscopy, and 6.8% required two bronchoscopies. In elderly cohorts, tracheal foreign bodies are obscured by nonspecific clinical presentations and a paucity of aspiration history, challenging timely diagnosis. Predominantly constituted by food particles, with a notable predilection for the left bronchial tree, these cases demand skilled bronchoscopic management, occasionally requiring sophisticated approaches for successful extraction. [ABSTRACT FROM AUTHOR]

Background: As the population rapidly ages, a growing number of families are engaging in care for individuals living with Alzheimer's disease and related dementias (ADRD). The perceived challenges and burdens that face informal caregivers are enormous.Objective: The objective of this study was to 1) explore from the family caregivers' perspective, the daily lives of individuals living with ADRD, and the challenges family caregivers encounter when caring for a family member with ADRD; and 2) to develop a comprehensive model with the endeavor to improve care for individuals with ADRD and their family caregivers.Methods: Posts were extracted from the ALZConnected online caregiving forum in May 2019. Guided by a triangular model focused on Caregiver, Individual with ADRD, and Context of Care, two researchers independently analyzed 654 posts with a combination of deductive and inductive thematic analysis approach. Researchers all agreed on finalized codes and themes.Results: Thematic analysis resulted in four themes: Individual with ADRD, Caregiver, Dynamic between Caregiver and Individual with ADRD, and Context of Care. The most frequently discussed topics among caregivers were informational and emotional support for caregivers, and the capabilities and functioning of individuals with ADRD.Conclusion: Online forums provide a valuable platform for caregivers to support each other informationally and emotionally, share care strategies, and navigate caregiving burdens. An expanded model was derived to support a comprehensive and dynamic approach to improve care for both caregivers and individuals with ADRD. The unique nature of the caregiver forum data is worthy of further data mining using a novel analysis approach. [ABSTRACT FROM AUTHOR]

Receptor for Advanced Glycation Endproducts (RAGE) is a multiligand member of the immunoglobulin superfamily of cell surface molecules which serves as a receptor for amyloid-β peptide (Aβ) on neurons, microglia, astrocytes, and cells of vessel wall. Increased expression of RAGE is observed in regions of the brain affected by Alzheimer's disease (AD), and Aβ-RAGE interaction in vitro leads to cell stress with the generation of reactive oxygen species and activation of downstream signaling mechanisms including the MAP kinase pathway. RAGE-mediated activation of p38 MAP kinase in neurons causes Aβ-induced inhibition of long-term potentiation in slices of entorhinal cortex. Increased expression of RAGE in an Aβ-rich environment, using transgenic mouse models, accelerates and accentuates pathologic, biochemical, and behavioral abnormalities compared with mice overexpressing only mutant amyloid-β protein precursor. Interception of Aβ interaction with RAGE, by infusion of soluble RAGE, decreases Aβ content and amyloid load, as well as improving learning/memory and synaptic function, in a murine transgenic model of Aβ accumulation. These data suggest that RAGE may be a therapeutic target for AD. [ABSTRACT FROM AUTHOR]

As an important molecule in the pathogenesis of Alzheimer's disease (AD), amyloid-β (Aβ) interferes with multiple aspects of mitochondrial function, including energy metabolism failure, production of reactive oxygen species (ROS) and permeability transition pore formation. Recent studies have demonstrated that Aβ progressively accumulates within mitochondrial matrix, providing a direct link to mitochondrial toxicity. Aβ-binding alcohol dehydrogenase (ABAD) is localized to the mitochondrial matrix and binds to mitochondrial Aβ. Interaction of ABAD with Aβ exaggerates Aβ-mediated mitochondrial and neuronal perturbation, leading to impaired synaptic function, and dysfunctional spatial learning/memory. Thus, blockade of ABAD/Aβ interaction may be a potential therapeutic strategy for AD. [ABSTRACT FROM AUTHOR]

Deficits in mitochondrial function are a characteristic finding in Alzheimer's disease (AD), though the mechanism remains to be clarified. Recent studies revealed that amyloid β peptide (Aβ) gains access into mitochondrial matrix, which was much more pronounced in both AD brain and transgenic mutant APP mice than in normal controls. Aβ progressively accumulates in mitochondria and mediates mitochondrial toxicity. Interaction of mitochondrial Aβ with mitochondrial enzymes such as amyloid β binding alcohol dehydrogenase (ABAD) exaggerates mitochondrial stress by inhibiting the enzyme activity, releasing reactive oxygen species (ROS), and affecting glycolytic, Krebs cycle and/or the respiratory chain pathways through the accumulation of deleterious intermediate metabolites. The pathways proposed may play a key role in the pathogenesis of this devastating neurodegenerative disorder, Alzheimer's disease. iubmb Life, 58: 686-694, 2006 [ABSTRACT FROM AUTHOR]

Mitochondrial and metabolic dysfunction have been linked to Alzheimer's disease for some time. Key questions regarding this association concern the nature and mechanisms of mitochondrial dysfunction, and whether such changes in metabolic properties are pathogenic or secondary, with respect to neuronal degeneration. In terms of mitochondria and Alzheimer's, altered function could reflect intrinsic properties of this organelle, potentially due to mutations in mitochondrial DNA, or extrinsic changes secondary to signal transduction mechanisms activated in the cytosol. This review presents data relevant to these questions, and considers the implication of recent findings demonstrating the presence of amyloid-β peptide in mitochondria, as well as intra-mitochondrial molecular targets with which it can interact. Regardless of the underlying mechanism(s), it is likely that mitochondrial dysfunction contributes to oxidant stress which is commonly observed in brains of patients with Alzheimer's and transgenic models of Alzheimer's-like pathology. [ABSTRACT FROM AUTHOR]

An important means of determining how amyloid-beta peptide(Aβ) affects cells is to identify specific macromolecular targets and assess how Aβ interaction with such targets impacts on cellular functions. On the one hand, cell surface receptors interacting with extracellular Aβ have been identified, and their engagement by amyloid peptide can trigger intracellular signaling cascades. Recent evidence has indicated a potentially significant role for deposition of intracellular Aβ in cell stress associated with amyloidosis. Thus, specific intracellular targets of Aβ might also be of interest. Our review evaluates the potential significance of Aβ interaction with a mitochondrial enzyme termed Aβ-binding alcohol dehydrogenase(ABAD), a member of the short-chain dehydrogenase-reductase family concentrated in mitochondria of neurones. Binding of Aβ to ABAD distorts the enzyme's structure, rendering it inactive with respect to its metabolic properties, and promotes mitochondrial generation of free radicals. Double transgenic mice in which increased levels of ABAD are expressed in an Aβ-rich environment, the latter provided by a mutant amyloid precursor protein transgene, demonstrate accelerated decline in spatial learning/memory and pathologic changes. These data suggest that mitochondria ABAD, ordinarily a contributor to metabolic homeostasis, has the capacity to become a pathogenic factor in an Aβ-rich environment. [ABSTRACT FROM AUTHOR]

Presents research which concluded that intracellular peptide ERAB may contribute to the neuronal dysfunction associated with Alzheimer's disease. Amyloid-Beta in pathogenesis of Alzheimer's disease; Amyloid-Beta and ERAB; Reaction of ERAB when cell culture is exposed to amyloid-Beta; Amyloid-Beta's toxic effect; Identification and cloning of ERAB; Tissue and cellular localization of ERAB; ERAB and amyloid-Beta-mediated cellular toxicity.

Abstract: Single stranded DNA often forms stable secondary structures under physiological conditions. These DNA secondary structures play important physiological roles. However, the analysis of such secondary structure folded DNA is often complicated because of its high thermodynamic stability and slow hybridization kinetics. In this article, we demonstrate that Y-shaped junction probes could be used for rapid and highly efficient detection of secondary structure folded DNA. Our approach contained a molecular beacon (MB) probe and an assistant probe. In the absence of target, the MB probe failed to hybridize with the assistant probe. Whereas, the MB probe and the assistant probe could cooperatively unwind the secondary structure folded DNA target to form a ternary Y-shaped junction structure. In this condition, the MB probe was also opened, resulting in separating the fluorophores from the quenching moiety and emitting the fluorescence signal. This approach allowed for the highly sensitive detection of secondary structure folded DNA target, such as a tau specific DNA fragment related to Alzheimer''s disease in this case. Additionally, this approach showed strong SNPs identifying capability. Furthermore, it was noteworthy that this newly proposed approach was capable of detecting secondary structure folded DNA target in cell lysate samples. [Copyright &y& Elsevier]

Tau hyperphosphorylation is a typical pathological change in Alzheimer's disease (AD) and is involved in the early onset and progression of AD. Epigenetic modification refers to heritable alterations in gene expression that are not caused by direct changes in the DNA sequence of the gene. Epigenetic modifications, such as noncoding RNA regulation, DNA methylation, and histone modification, can directly or indirectly affect the regulation of tau phosphorylation, thereby participating in AD development and progression. This review summarizes the current research progress on the mechanisms of epigenetic modification associated with tau phosphorylation. [ABSTRACT FROM AUTHOR]

Since adenosine triphosphate (ATP) and reactive oxygen species (ROS) are closely related to neuron functions and the pathogenesis of Alzheimer's disease, herein, the first example of using a dual-responsive zeolitic imidazolate framework-90 (ZIF-90) to fabricate a single fluorescent probe, CuNCs/ZIF@P1-P2/ZIF, was reported, which specifically and sensitively responded to intracellular level fluctuations of ATP and ROS both in neuronal and tumor cells without obvious cross-talking. Through a stepwise in situ growth method, ROS-responsive glutathione-stabilized copper nanoclusters (GSH-CuNCs) and double tagged ATP aptamer hybrid chain (P1-P2) were prepared and respectively encapsulated into the inner and outer ZIF-90. The obtained CuNCs/ZIF@P1-P2/ZIF probe as a tandem system could firstly respond to ATP in an "off-to-on" mode, in which, the quenched fluorescence of FAM by BHQ1 attached on P2 was recovered through the competitive displacement between ATP and ZIF-90, leading to the release of FAM from ZIF-90. Upon collapse of the outer ZIF-90, the strong emission of CuNCs enclosed in the inner ZIF-90 was subsequently quenched in the presence of ROS. Accompanied with high sensitivity, selectivity and accuracy, the resultant fluorescent probe exhibited good performance and properties for tracking the level variations of ATP and ROS in SH-SY5Y and Hela cells under different stimulations. This strategy highlighted the potential of the ZIF-90 based nanocomposite for multi-targets detection, and also provided a value tool for the early diagnosis of diseases. • A dual-responsive ZIF-90 based nanocomposite was prepared. • An effective strategy for ATP and ROS combined detection was developed. • The composite selectively responded to ATP and ROS without cross-talking. • Imaging in living SH-SY5Y cells under different stimulations was realized. [ABSTRACT FROM AUTHOR]

Oligomeric amyloid-β (Aβ) interferes with long term potentiation (LTP) and cognitive processes, suggesting that Aβ peptides may play a role in the neuronal dysfunction which characterizes the early stages of Alzheimer's disease (AD). Multiple lines of evidence have highlighted RAGE (receptor for advanced glycation end-products) as a receptor involved in Aβ-induced neuronal and synaptic dysfunction. In the present study, we investigated the effect of oligomeric soluble Aβ_{1-42} on LTP elicited by the stimulation of different intracortical pathways in the mouse visual cortex. A variety of nanomolar concentrations (20–200 nM) of Aβ_{1-42} were able to inhibit LTP in cortical layer II-III induced by either white matter (WM-Layer II/III) or the layer II/III (horizontal pathway) stimulation, whereas the inhibition of LTP was more susceptible to Aβ_{1-42}, which occurred at 20 nM of Aβ, when stimulating layer II-III horizontal pathway. Remarkably, cortical slices were resistant to nanomolar Aβ_{1-42} in the absence of RAGE (genetic deletion of RAGE) or blocking RAGE by RAGE antibody. These results indicate that nanomolar Aβ inhibits LTP expression in different neocortical circuits. Crucially, it is demonstrated that Aβ-induced reduction of LTP in different cortical pathways is mediated by RAGE. [ABSTRACT FROM AUTHOR]

Soluble amyloid-β(Aβ) peptide is likely to play a key role during early stages of Alzheimer's disease (AD) by perturbing synaptic function and cognitive processes. Receptor for advanced glycation end products (RAGE) has been identified as a receptor involved in Aβ-induced neuronal dysfunction. We investigated the role of neuronal RAGE in Aβ-induced synaptic dysfunction in the entorhinal cortex, an area of the brain important in memory processes that is affected early in AD. We found that soluble oligomeric Aβ peptide (Aβ42) blocked long-term potentiation (LTP), but did not affect long-term depression, paired-pulse facilitation, or basal synaptic transmission. In contrast, Aβ did not inhibit LTP in slices from RAGE-null mutant mice or in slices from wild-type mice treated with anti-RAGE IgG. Similarly, transgenic mice expressing a dominant-negative form of RAGE targeted to neurons showed normal LTP in the presence of Aβ, suggesting that neuronal RAGE functions as a signal transducer for Aβ-mediated LTP impairment. To investigate intracellular pathway transducing RAGE activation by Aβ, we used inhibitors of stress activated kinases. We found that inhibiting p38 mitogen-activated protein kinase (p38 MAPK), but not blocking c-Jun N-terminal kinase activation, was capable of maintaining LTP in Aβ-treated slices. Moreover, Aβ-mediated enhancement of p38 MAPK phosphorylation in cortical neurons was reduced by blocking antibodies to RAGE. Together, our results indicate that Aβ impairs LTP in the entorhinal cortex through neuronal RAGE-mediated activation of p38 MAPK. [ABSTRACT FROM AUTHOR]

Alzheimer patients have increased levels of both the 42 amyloid-β-peptide (Aβ) and the amyloid binding alcohol dehydrogenase (ABAD), which is an intracellular binding site for Aβ. The overexpression of A and ABAD in transgenic mice has shown that the binding of Aβ to ABAD results in amplified neuronal stress and impairment of learning and memory. From a proteomic analysis of the brains from these animals, we have identified for the first time that the protein endophilin I increases in Alzheimer diseased brain. The increase in endophilin I levels in neurons is linked to an increase in the activation of the stress kinase c-Jun N-terminal kinase with the subsequent death of the neurons. We also demonstrate in living animals that the expression level of endophilin I is an indicator for the interaction of ABAD and Aβ as its expression levels return to normal if this interaction is perturbed. Therefore this identifies endophilin I as a new indicator of the progression of Alzheimer disease. [ABSTRACT FROM AUTHOR]

Collapsin response mediator protein 2 (CRMP2) is an abundant brain-enriched protein that can regulate microtubule assembly in neurons. This function of CRMP2 is regulated by phosphorylation by glycogen synthase kinase 3 (GSK3) and cyclin-dependent kinase 5 (Cdk5). Here, using novel phosphospecific antibodies, we demonstrate that phosphorylation of CRMP2 at Ser522 (Cdk5-mediated) is increased in Alzheimer’s disease (AD) brain, while CRMP2 expression and phosphorylation of the closely related isoform CRMP4 are not altered. In addition, CRMP2 phosphorylation at the Cdk5 and GSK3 sites is increased in cortex and hippocampus of the triple transgenic mouse [presenilin-1 (PS1)M146VKI; Thy1.2-amyloid precursor protein (APP)swe; Thy1.2tauP301L] that develops AD-like plaques and tangles, as well as the double (PS1M146VKI; Thy1.2-APPswe) transgenic mouse. The hyperphosphorylation is similar in magnitude to that in human AD and is evident by 2 months of age, ahead of plaque or tangle formation. Meanwhile, there is no change in CRMP2 phosphorylation in two other transgenic mouse lines that display elevated amyloid β peptide levels (Tg2576 and APP/amyloid β-binding alcohol dehydrogenase). Similarly, CRMP2 phosphorylation is normal in hippocampus and cortex of Tau(P301L) mice that develop tangles but not plaques. These observations implicate hyperphosphorylation of CRMP2 as an early event in the development of AD and suggest that it can be induced by a severe APP over-expression and/or processing defect. [ABSTRACT FROM AUTHOR]

LRP (low-density lipoprotein receptor-related protein) is linked to Alzheimer''s disease (AD). Here, we report amyloid β-peptide Aβ40 binds to immobilized LRP clusters II and IV with high affinity (Kd = 0.6–1.2 nM) compared to Aβ42 and mutant Aβ, and LRP-mediated Aβ brain capillary binding, endocytosis, and transcytosis across the mouse blood-brain barrier are substantially reduced by the high β sheet content in Aβ and deletion of the receptor-associated protein gene. Despite low Aβ production in the brain, transgenic mice expressing low LRP-clearance mutant Aβ develop robust Aβ cerebral accumulations much earlier than Tg-2576 Aβ-overproducing mice. While Aβ does not affect LRP internalization and synthesis, it promotes proteasome-dependent LRP degradation in endothelium at concentrations >1 μM, consistent with reduced brain capillary LRP levels in Aβ-accumulating transgenic mice, AD, and patients with cerebrovascular β-amyloidosis. Thus, low-affinity LRP/Aβ interaction and/or Aβ-induced LRP loss at the BBB mediate brain accumulation of neurotoxic Aβ. [Copyright &y& Elsevier]

The article presents a study which determined whether amyloid-Β peptide might be associated with mitochondria. Over the years, there have been many postulated links between mitochondrial function/dysfunction and Alzheimer's disease. Principal findings are given. Conclusions and significance of the study are discussed.