Disaggregation Behavior of Amyloid β Fibrils by Anthocyanins Studied by Total-Internal-Reflection-Fluorescence Microscopy Coupled with a Wireless Quartz-Crystal Microbalance Biosensor

Noi K., Ikenaka K., Mochizuki H., et al. Disaggregation Behavior of Amyloid β Fibrils by Anthocyanins Studied by Total-Internal-Reflection-Fluorescence Microscopy Coupled with a Wireless Quartz-Crystal Microbalance Biosensor. Analytical Chemistry, 93(32), 11176-11183, August 17, 2021. Copyright © 2021, American Chemical Society. https://doi.org/10.1021/acs.analchem.1c01720.Amyloid fibrils are formed from various proteins, some of which cause the corresponding neurodegenerative disorders, such as Alzheimer's and Parkinson's diseases. It has been reported that many compounds inhibit the formation of amyloid fibrils. Anthocyanins are flavonoid pigments present in fruits and vegetables, which are known to suppress symptoms related with Alzheimer's disease. However, the influence of anthocyanins on the amyloid fibril remains unclear. Here, we succeeded in the direct monitoring of the disaggregation reaction of single amyloid β (Aβ) fibrils by anthocyanins using total-internal-reflection-fluorescence microscopy with a quartz-crystal microbalance (TIRFM-QCM). It is found that the disassembly activity to the Aβ fibrils depends on the number of hydroxyl groups in six-membered ring B of anthocyanin, and only delphinidin-3-galactoside, possessing three hydroxyl groups there, shows high disassembly activity. Our results show the importance of the number of hydroxyl groups and demonstrate the usefulness of TIRFM-QCM as a powerful tool in studying interactions between amyloid fibrils and compounds

Clinicopathological characteristics of patients with amyotrophic lateral sclerosis resulting in a totally locked-in state (communication Stage V)

In the present study, we performed a comprehensive analysis to clarify the clinicopathological characteristics of patients with amyotrophic lateral sclerosis (ALS) that had progressed to result in a totally locked-in state (communication Stage V), in which all voluntary movements are lost and communication is impossible. In 11 patients, six had phosphorylated TAR DNA-binding protein 43 (pTDP-43)-immunoreactive (ir) neuronal cytoplasmic inclusions (NCI), two had fused in sarcoma (FUS)-ir NCI, and three had copper/zinc superoxide dismutase (SOD1)-ir NCI. The time from ALS onset to the need for tracheostomy invasive ventilation was less than 24 months in ten patients. Regardless of accumulated protein, all the patients showed common lesions in the pallido-nigro-luysian system, brainstem reticular formation, and cerebellar efferent system, in addition to motor neurons. In patients with pTDP-43-ir NCI, patients with NCI in the hippocampal dentate granule neurons (DG) showed a neuronal loss in the cerebral cortex, and patients without NCI in DG showed a preserved cerebral cortex. By contrast, in patients with FUS-ir NCI, patients with NCI in DG showed a preserved cerebral cortex and patients without NCI in DG showed marked cerebral degeneration. The cerebral cortex of patients with SOD1-ir NCI was preserved. Together, these findings suggest that lesions of the cerebrum are probably not necessary for progression to Stage V. In conclusion, patients with ALS that had progressed to result in communication Stage V showed rapidly-progressed symptoms, and their common lesions could cause the manifestations of communication Stage V.ArticleACTA NEUROPATHOLOGICA COMMUNICATIONS.4:107(2016)journal articl

MDCT findings of extrapancreatic nerve plexus invasion by pancreas head carcinoma: correlation with en bloc pathological specimens and diagnostic accuracy

金沢大学医薬保健研究域Objective: To elucidate the multi-detector row computed tomography (MDCT) findings of extrapancreatic nerve plexus (PLX) invasion by pancreas head carcinoma (PhC) by "point-by-point" correlation with en bloc pathological specimens and to assess their diagnostic accuracy. Methods: Each pathological section of PhC and adjusted double oblique multiplanar reconstruction MDCT images were correlated in 554 sections from 37 patients. The diagnostic accuracy of the MDCT patterns derived was assessed by blind reading. Results: PLX invasion with fibrosis showed mass or strand shape (85.6%) or coarse reticula (13.3%). The CT findings were divided into fine reticular and linear, coarse reticular, mass and strand, and nodular patterns. PLX invasion was revealed pathologically in 92% of the regions of investigation showing the mass and strand pattern and 63% of the coarse reticular pattern (all continuous with PhC), and they were highly suggestive of PLX invasion by PhC on MDCT images (p < 0.001). Sensitivity, specificity, accuracy, and positive and negative predictive values of these MDCT findings in the diagnosis of PLX invasion were 100% (25/25), 83.3% (10/12), 94.6% (35/37), 92.6% (25/27) and 100% (10/10), respectively. Conclusion: The mass and strand pattern and the coarse reticular pattern continuous with PhC on MDCT images were highly suggestive of PLX invasion by PhC. © 2010 European Society of Radiology

Myofibroblasts impair myocardial impulse propagation by heterocellular connexin43 gap-junctional coupling through micropores

Aim: Composite population of myofibroblasts (MFs) within myocardial tissue is known to alter impulse propagation, leading to arrhythmias. However, it remains unclear whether and how MFs alter their propagation patterns when contacting cardiomyocytes (CMs) without complex structural insertions in the myocardium. We attempted to unveil the effects of the one-sided, heterocellular CM-MF connection on the impulse propagation of CM monolayers without the spatial insertion of MFs as an electrical or mechanical obstacle.Methods and results: We evaluated fluo8-based spatiotemporal patterns in impulse propagation of neonatal rat CM monolayers cultured on the microporous membrane having 8-μm diameter pores with co-culture of MFs or CMs on the reverse membrane side (CM-MF model or CM-CM model, respectively). During consecutive pacing at 1 or 2 Hz, the CM monolayers exhibited forward impulse propagation from the pacing site with a slower conduction velocity (θ) and a larger coefficient of directional θ variation in the CM-MF model than that in the CM-CM model in a frequency-dependent manner (2 Hz &gt;1 Hz). The localized placement of an MF cluster on the reverse side resulted in an abrupt segmental depression of the impulse propagation of the upper CM layer, causing a spatiotemporally non-uniform pattern. Dye transfer of the calcein loaded in the upper CM layer to the lower MF layer was attenuated by the gap-junction inhibitor heptanol. Immunocytochemistry identified definitive connexin 43 (Cx43) between the CMs and MFs in the membrane pores. MF-selective Cx43 knockdown in the MF layer improved both the velocity and uniformity of propagation in the CM monolayer.Conclusion: Heterocellular Cx43 gap junction coupling of CMs with MFs alters the spatiotemporal patterns of myocardial impulse propagation, even in the absence of spatially interjacent and mechanosensitive modulations by MFs. Moreover, MFs can promote pro-arrhythmogenic impulse propagation when in face-to-face contact with the myocardium that arises in the healing infarct border zone

Interaction Rating Scale (IRS) as an Evidence-Based Practical Index of Children’s Social Skills and Parenting

Background: The purpose of this paper is to describe the features of the Interaction Rating Scale (IRS) as an evidence-based practical index of children’s social skills and parenting.Methods: The participants in our study, which was conducted as part of a Japan Science and Technology Agency (JST) project, were 370 dyads of children (aged 18, 30, and 42 month) and 81 dyads of 7-year-old children with their caregivers. The participants completed the five minute interaction session and were observed using the IRS.Results: The results indicated that the IRS can measure children’s social skill development and parenting with high validity. Along with the discriminate validity for pervasive development disorder (PDD), attention-deficit/hyperactivity disorder (ADHD), abuse and maltreatment, a high correlation with the SDQ (Strength and Difficulties Questionnaire), and high reliability, the IRS is effective in describing features of social skill development.Conclusions: The IRS provides further evidence of the fact that in order to study children’s social skill development, it is important to evaluate various features of the caregiver-child interaction as a predictor of social skills

Ultrasonication-based rapid amplification of α-synuclein aggregates in cerebrospinal fluid

Kakuda K., Ikenaka K., Araki K., et al. Ultrasonication-based rapid amplification of α-synuclein aggregates in cerebrospinal fluid. Scientific Reports 9, 6001 (2019); https://doi.org/10.1038/s41598-019-42399-0.α-Synuclein aggregates, a key hallmark of the pathogenesis of Parkinson’s disease, can be amplified by using their seeding activity, and the evaluation of the seeding activity of cerebrospinal fluid (CSF) is reportedly useful for diagnosis. However, conventional shaking-based assays are time-consuming procedures, and the clinical significance of the diversity of seeding activity among patients remains to be clarified. Previously, we reported a high-throughput ultrasonication-induced amyloid fibrillation assay. Here, we adapted this assay to amplify and detect α-synuclein aggregates from CSF, and investigated the correlation between seeding activity and clinical indicators. We confirmed that this assay could detect α-synuclein aggregates prepared in vitro and also aggregates released from cultured cells. The seeding activity of CSF correlated with the levels of α-synuclein oligomers measured by an enzyme-linked immunosorbent assay. Moreover, the seeding activity of CSF from patients with Parkinson’s disease was higher than that of control patients. Notably, the lag time of patients with Parkinson’s disease was significantly correlated with the MIBG heart-to-mediastinum ratio. These findings showed that our ultrasonication-based assay can rapidly amplify misfolded α-synuclein and can evaluate the seeding activity of CSF

Discovery of New Hydrothermal Activity and Chemosynthetic Fauna on the Central Indian Ridge at 18°–20°S

Indian Ocean hydrothermal vents are believed to represent a novel biogeographic province, and are host to many novel genera and families of animals, potentially indigenous to Indian Ocean hydrothermal systems. In particular, since its discovery in 2001, much attention has been paid to a so-called ‘scaly-foot’ gastropod because of its unique iron-sulfide-coated dermal sclerites and the chemosynthetic symbioses in its various tissues. Despite increasing interest in the faunal assemblages at Indian Ocean hydrothermal vents, only two hydrothermal vent fields have been investigated in the Indian Ocean. Here we report two newly discovered hydrothermal vent fields, the Dodo and Solitaire fields, which are located in the Central Indian Ridge (CIR) segments 16 and 15, respectively. Chemosynthetic faunal communities at the Dodo field are emaciated in size and composition. In contrast, at the Solitaire field, we observed faunal communities that potentially contained almost all genera found at CIR hydrothermal environments to date, and even identified previously unreported taxa. Moreover, a new morphotype of ‘scaly-foot’ gastropod has been found at the Solitaire field. The newly discovered ‘scaly-foot’ gastropod has similar morphological and anatomical features to the previously reported type that inhabits the Kairei field, and both types of ‘scaly-foot’ gastropods genetically belong to the same species according to analyses of their COI gene and nuclear SSU rRNA gene sequences. However, the new morphotype completely lacks an iron-sulfide coating on the sclerites, which had been believed to be a novel feature restricted to ‘scaly-foot’ gastropods. Our new findings at the two newly discovered hydrothermal vent sites provide important insights into the biodiversity and biogeography of vent-endemic ecosystems in the Indian Ocean