Foreign object ingestions are a common occurrence in pediatrics, often necessitating endoscopic or surgical intervention. The ingestion of multiple magnets poses an increased risk for serious complications. Our article presents a case of a five-year-old boy who swallowed two pennies and four magnets.
View Article and Find Full Text PDFBackground: Pyrrolizidine alkaloids (PAs) are naturally occurring plant toxins associated with potential hepatic and carcinogenic diseases in humans and animals. The concern over PAs has increased as the consumption of herbal medicines has increased.
Objective: This study aimed to develop and validate a sensitive analytical method to determine 28 PAs in five herbal medicines using liquid chromatography (LC)-electrospray ionization (ESI)-tandem mass spectrometry (MS/MS).
Amyloid-β (Aβ) accumulation, metal ion dyshomeostasis, oxidative stress, and cholinergic deficit are four major characteristics of Alzheimer's disease (AD). Herein, we report the reactivities of 12 flavonoids against four pathogenic elements of AD: metal-free and metal-bound Aβ, free radicals, and acetylcholinesterase. A series of 12 flavonoids was selected based on the molecular structures that are responsible for multiple reactivities including hydroxyl substitution and transfer of the B ring from C2 to C3.
View Article and Find Full Text PDFMitochondrial DNA B Resour
April 2021
and are important herbal medicine which of rhizomatous herbaceous perennial plant of the family Zingiberaceae. This study generated a complete chloroplast genome sequence of three medicinal species were characterized by de novo assembly with whole genome sequencing data. The length of complete chloroplast genome were 162,180 bp (), 162,266 bp (), and 162,133 bp (), respectively, with four structures that were included in large single copy region (87,001 bp, 87,042 bp, and 87,013 bp), small single copy region (15,681 bp, 15,710 bp, and 15,622 bp), and duplicated inverted regions (29,749 bp, 29,757 bp and 29,749 bp of each).
View Article and Find Full Text PDFWe report a prodrug, , to overcome the shortcomings of an anti-neuroinflammatory molecule, -diacetyl--phenylenediamine (), in biological applicability for potential therapeutic applications. We suspect that can release through endogenous enzymatic bioconversion. Consequently, exhibits in vivo efficacies in alleviating neuroinflammation, reducing amyloid-β aggregate accumulation, and improving cognitive function in Alzheimer's disease transgenic mice.
View Article and Find Full Text PDFBackground: COVID-19 has disrupted the 2020-2021 residency application cycle with the cancellation of away rotations and in-person interviews. This study seeks to investigate the feasibility and utility of video conferencing technology (VCT) as an opportunity for applicants to interact with faculty from outside programs.
Methods: 18 prospective urology applicants were randomized to 6 urology programs to give a virtual grand rounds (VGR) talk.
Multiple pathogenic elements, including reactive oxygen species, amyloidogenic proteins, and metal ions, are associated with the development of neurodegenerative disorders. We report minimalistic redox-based principles for preparing compact aromatic compounds by derivatizing the phenylene moiety with various functional groups. These molecular agents display enhanced reactivities against multiple targets such as free radicals, metal-free amyloid-β (Aβ), and metal-bound Aβ that are implicated in the most common form of dementia, Alzheimer's disease (AD).
View Article and Find Full Text PDFAs a central feature of neuroinflammation, microglial dysfunction has been increasingly considered a causative factor of neurodegeneration implicating an intertwined pathology with amyloidogenic proteins. Herein, we report the smallest synthetic molecule (,'-diacetyl--phenylenediamine [DAPPD]), simply composed of a benzene ring with 2 acetamide groups at the position, known to date as a chemical reagent that is able to promote the phagocytic aptitude of microglia and subsequently ameliorate cognitive defects. Based on our mechanistic investigations in vitro and in vivo, 1) the capability of DAPPD to restore microglial phagocytosis is responsible for diminishing the accumulation of amyloid-β (Aβ) species and significantly improving cognitive function in the brains of 2 types of Alzheimer's disease (AD) transgenic mice, and 2) the rectification of microglial function by DAPPD is a result of its ability to suppress the expression of NLRP3 inflammasome-associated proteins through its impact on the NF-κB pathway.
View Article and Find Full Text PDFAmyloidogenic peptides are considered central pathological contributors towards neurodegeneration as observed in neurodegenerative disorders [, amyloid-β (Aβ) peptides in Alzheimer's disease (AD)]; however, their roles in the pathologies of such diseases have not been fully elucidated since they are challenging targets to be studied due to their heterogeneous nature and intrinsically disordered structure. Chemical approaches to modify amyloidogenic peptides would be valuable in advancing our molecular-level understanding of their involvement in neurodegeneration. Herein, we report effective chemical strategies for modification of Aβ peptides (, coordination and coordination-/photo-mediated oxidation) implemented by a single Ir(iii) complex in a photo-dependent manner.
View Article and Find Full Text PDFComplex amyloid aggregation of amyloid-β (1-40) (Aβ) in terms of monomer structures has not been fully understood. Herein, we report the microscopic mechanism and pathways of Aβ aggregation with macroscopic viewpoints through tuning its initial structure and solubility. Partial helical structures of Aβ induced by low solvent polarity accelerated cytotoxic Aβ amyloid fibrillation, while predominantly helical folds did not aggregate.
View Article and Find Full Text PDFWe report orobol as a multifunctional isoflavone with the ability to (i) modulate the aggregation pathways of both metal-free and metal-bound amyloid-β, (ii) interact with metal ions, (iii) scavenge free radicals, and (iv) inhibit the activity of acetylcholinesterase. Such a framework with multifunctionality could be useful for developing chemical reagents to advance our understanding of multifaceted pathologies of neurodegenerative disorders, including Alzheimer's disease.
View Article and Find Full Text PDFAggregation of amyloidogenic peptides could cause the onset and progression of neurodegenerative diseases, such as Alzheimer's disease and Parkinson's disease. These amyloidogenic peptides can coordinate to metal ions, including Zn(ii), which can subsequently affect the peptides' aggregation and toxicity, leading to neurodegeneration. Unfortunately, the detection of metal-amyloidogenic peptide complexation has been very challenging.
View Article and Find Full Text PDFAggregation of amyloid-β (Aβ) peptides is implicated in the development of Alzheimer's disease (AD), the most common type of dementia. Thus, numerous efforts to identify chemical tactics to control the aggregation pathways of Aβ peptides have been made. Among them, transition metal complexes as a class of chemical modulators against Aβ aggregation have been designed and utilized.
View Article and Find Full Text PDFNeurodegenerative diseases pose a substantial socioeconomic burden on society. Unfortunately, the aging world population and lack of effective cures foreshadow a negative outlook. Although a large amount of research has been dedicated to elucidating the pathologies of neurodegenerative diseases, their principal causes remain elusive.
View Article and Find Full Text PDFProteins from the S100 family perform numerous functions and may contribute to Alzheimer's disease (AD). Herein, we report the effects of S100A8/S100A9 heterooligomer calprotectin (CP) and the S100B homodimer on metal-free and metal-bound amyloid-β (Aβ; Aβ40 and Aβ42) aggregation in vitro. Studies performed with CP-Ser [S100A8(C42S)/S100A9(C3S) oligomer] indicate that the protein influences the aggregation profile for Aβ40 in both the absence and presence of metal ions [i.
View Article and Find Full Text PDFA catecholamine neurotransmitter, dopamine (DA), is suggested to be linked to the pathology of dementia; however, the involvement of DA and its structural analogues in the pathogenesis of Alzheimer's disease (AD), the most common form of dementia, composed of multiple pathogenic factors has not been clear. Herein, we report that DA and its rationally designed structural derivatives (1-6) based on DA's oxidative transformation are able to modulate multiple pathological elements found in AD [i.e.
View Article and Find Full Text PDFAn amyloidogenic peptide, amyloid-β (Aβ), has been implicated as a contributor to the neurotoxicity of Alzheimer's disease (AD) that continues to present a major socioeconomic burden for our society. Recently, the use of metal complexes capable of cleaving peptides has arisen as an efficient tactic for amyloid management; unfortunately, little has been reported to pursue this strategy. Herein, we report a novel approach to validate the hydrolytic cleavage of divalent metal complexes toward two major isoforms of Aβ (Aβ and Aβ) and tune their proteolytic activity based on the choice of metal centers (M = Co, Ni, Cu, and Zn) which could be correlated to their anti-amyloidogenic properties.
View Article and Find Full Text PDFTo elucidate the involvement of individual and inter-related pathological factors [i.e., amyloid-β (Aβ), metals, and oxidative stress] in the pathogenesis of Alzheimer's disease (AD), chemical tools have been developed.
View Article and Find Full Text PDFAggregates of amyloidogenic peptides are involved in the pathogenesis of several degenerative disorders. Herein, an iridium(III) complex, Ir-1, is reported as a chemical tool for oxidizing amyloidogenic peptides upon photoactivation and subsequently modulating their aggregation pathways. Ir-1 was rationally designed based on multiple characteristics, including 1) photoproperties leading to excitation by low-energy radiation; 2) generation of reactive oxygen species responsible for peptide oxidation upon photoactivation under mild conditions; and 3) relatively easy incorporation of a ligand on the Ir center for specific interactions with amyloidogenic peptides.
View Article and Find Full Text PDFProtein inactivation by reactive oxygen species (ROS) such as singlet oxygen ((1)O2) and superoxide radical (O2(•-)) is considered to trigger cell death pathways associated with protein dysfunction; however, the detailed mechanisms and direct involvement in photodynamic therapy (PDT) have not been revealed. Herein, we report Ir(III) complexes designed for ROS generation through a rational strategy to investigate protein modifications by ROS. The Ir(III) complexes are effective as PDT agents at low concentrations with low-energy irradiation (≤ 1 J cm(-2)) because of the relatively high (1)O2 quantum yield (> 0.
View Article and Find Full Text PDFThe complex and multifaceted pathology of Alzheimer's disease (AD) continues to present a formidable challenge to the establishment of long-term treatment strategies. Multifunctional compounds able to modulate the reactivities of various pathological features, such as amyloid-β (Aβ) aggregation, metal ion dyshomeostasis, and oxidative stress, have emerged as a useful tactic. Recently, an incorporation approach to the rational design of multipurpose small molecules has been validated through the production of a multifunctional ligand (ML) as a potential chemical tool for AD.
View Article and Find Full Text PDFSpectrochim Acta A Mol Biomol Spectrosc
January 2014
A quinoline-based simple receptor (bis(2-quinolinylmethyl)benzylamine = 1) as a Zn(2+) selective fluorescent chemosensor showed a large fluorescent enhancement with a blue shift in the presence of Zn(2+) which is attributed to a chelation enhanced fluorescence (CHEF) effect with inhibition of a photoinduced electron transfer (PET) process of 1. In particular, this receptor could clearly distinguish Zn(2+) from Cd(2+). The binding mode of 1 and Zn(2+) was found to be a 1:1 and confirmed by Job plot, (1)H NMR titration and ESI-mass spectrometry analysis.
View Article and Find Full Text PDFA new metal ion sensor that contains quinoline and pyridylaminophenol has been synthesized. In acetonitrile and in the presence of Zn(2+), the sensor fluoresces. In contrast, in aqueous solutions the sensor fluoresces in the presence of Cd(2+).
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