Article
Cell Biology
Kerry C. Ryan, Zahra Ashkavand, Shaarika Sarasija, Jocelyn T. Laboy, Rohan Samarakoon, Kenneth R. Norman
Summary: Metabolic dysfunction and protein aggregation are common characteristics in age-related neurodegenerative diseases. Mutations in presenilin genes can lead to familial Alzheimer's disease, while loss of SEL-12/presenilin results in hyperactivation of the mTORC1 pathway. This hyperactivation exacerbates proteostasis defects and neuronal dysfunction in sel-12 mutants, highlighting the critical role of presenilin in promoting neuronal health.
Review
Biochemistry & Molecular Biology
Mehdi Eshraghi, Aida Adlimoghaddam, Amir Mahmoodzadeh, Farzaneh Sharifzad, Hamed Yasavoli-Sharahi, Shahrokh Lorzadeh, Benedict C. Albensi, Saeid Ghavami
Summary: Alzheimer's disease is a debilitating neurological disorder with no current cure. Pathological features such as amyloid plaques and tau tangles are characteristic of AD, but targeting these has not shown desired efficacy in patients. Autophagy, inflammation, and microglia play significant roles in AD pathogenesis and may provide potential therapeutic targets.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2021)
Article
Astronomy & Astrophysics
Aleksandr Petrashchuk, S. A. Anfinogentov, V. V. Fedenev, P. N. Mager, D. Yu Klimushkin
Summary: Numerical and analytical analysis of magnetohydrodynamic (MHD) waves in solar coronal arcades is conducted. A semicylinder slab model is used to represent the field lines and magnetic shells. The study considers finite plasma pressure and the 'corrugational' perturbations. The analysis reveals the existence of two oscillation modes, the Alfven and slow magnetosonic modes, coupled due to field line curvature. The results show that the waves are concentrated in the Alfven and magnetosonic transparent regions, bounded by resonance surfaces and cut-off frequencies.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
D. Agapova, S. A. Belov, N. E. Molevich, D. Zavershinskii
Summary: The study investigates the impact of solar atmospheric non-uniformity and non-adiabatic processes on magnetoacoustic waves, revealing a significant effect of thermal misbalance on slow waves and the primary dispersion mechanism for fast waves being the geometric magnetic structure. This has important implications for estimating plasma parameters and non-adiabatic processes using magnetoacoustic waves.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
Mohammad Sadeghi, Karam Bahari, Kayoomars Karami
Summary: Observations indicate the existence of twisted magnetic flux tubes and plasma flow in the solar atmosphere. The goal of this study is to determine the damping rate of sausage modes in the presence of magnetic twist and plasma flow. By numerically solving the dispersion relation for sausage modes in a non-uniform layer with magnetic pores under the condition of slow continuity, we find that the effect of twisted magnetic field on resonance absorption is greater for low speed plasma flow than for high speed.
ASTROPHYSICAL JOURNAL
(2023)
Article
Cell Biology
Benjamin Chun-Kit Tong, Aston Jiaxi Wu, Alexis Shiying Huang, Rui Dong, Sandeep Malampati, Ashok Iyaswamy, Senthilkumar Krishnamoorthi, Sravan Gopalkrishnashetty Sreenivasmurthy, Zhou Zhu, Chengfu Su, Jia Liu, Juxian Song, Jia-Hong Lu, Jieqiong Tan, Weidong Pan, Min Li, King-Ho Cheung
Summary: This study identified a mechanism of impairment in the macroautophagy/autophagy-lysosomal pathway (ALP) in Alzheimer's disease, mediated by the lysosomal TPCN2/TPC2 channel. Targeting TPCN2 was shown to restore lysosomal function and reduce amyloid plaque accumulation, suggesting a potential therapeutic strategy for AD treatment in the future.
Review
Genetics & Heredity
Nicholas Schultheis, Robert Becker, Gelila Berhanu, Alexander Kapral, Matthew Roseman, Shalini Shah, Alyssa Connell, Scott Selleck
Summary: Heparan sulfate modified proteins or proteoglycans (HSPGs) play important roles in cell signaling, membrane trafficking, autophagy and lipid metabolism, all of which are associated with neurodegenerative diseases such as Alzheimer's disease (AD). Altering heparan sulfate structure and function could potentially counter AD-associated pathological processes and improve cellular deficits.
FRONTIERS IN GENETICS
(2023)
Article
Astronomy & Astrophysics
S. Krishna Prasad, T. Van Doorsselaere
Summary: The study utilizing high-resolution EUV imaging observations reveals that sloshing oscillations can transform into standing waves, confirming recent numerical studies. By introducing a new analytical expression, the oscillation properties were successfully extracted, showing substantial plasma cooling during the oscillation.
ASTROPHYSICAL JOURNAL
(2021)
Article
Astronomy & Astrophysics
Daye Lim, Valery M. Nakariakov, Yong-Jae Moon
Summary: This study investigates slow magnetoacoustic oscillations in stellar coronal loops with gravitational stratification, focusing on resonant periods and the effects of various factors. Results show that the discrepancy between stratified and nonstratified loops is higher in density perturbations. The periods in stratified loops are slightly longer than in nonstratified loops, with calculated periods consistent with observed stellar quasi-periodic pulsations.
ASTROPHYSICAL JOURNAL
(2022)
Article
Mathematics, Applied
Naziru M. Awal, Irving R. Epstein, Tasso J. Kaper, Theodore Vo
Summary: Symmetry-breaking in coupled, identical, fast-slow systems leads to a diverse range of dynamic behaviors, including significant differences in amplitude and frequency as well as qualitatively distinct rhythms between oscillators associated with different functional states. A novel method is presented to analyze these systems, identifying key geometric structures responsible for the symmetry-breaking and demonstrating the robust emergence of various types of symmetry-breaking rhythms. The method is illustrated with two prototypical fast-slow systems: the van der Pol equation describing electrical circuits and the Lengyel-Epstein model of chemical oscillators.
Article
Cell Biology
Lucia Barazzuol, Domenico Cieri, Nicola Facchinello, Tito Cali, Philip Washbourne, Francesco Argenton, Paola Pizzo
Summary: This study generated a zebrafish line with a psen2 knockout, and found that the absence of the protein does not significantly affect Notch signaling, but leads to an exaggeration of locomotor response, a decrease in ER-mitochondria contacts, and an increase in basal autophagy. The protein also plays a role in mitochondrial axonal transport, and its downregulation reduces organelle flux in zebrafish sensory neurons. These findings highlight zebrafish as a valuable model organism for studying PS2 functions and testing potential therapies for Alzheimer's disease.
Article
Neurosciences
Miguel Dasilva, Alessandra Camassa, Alvaro Navarro-Guzman, Antonio Pazienti, Lorena Perez-Mendez, Gorka Zamora-Lopez, Maurizio Mattia, Maria V. Sanchez-Vivesa
Summary: Different groups of cortical neurons are able to engage in complex dynamic patterns in the brain, with higher complexity observed during wakefulness. As anesthesia levels decrease, there is a modulation of slow oscillation frequency along with an increase in perturbational and spontaneous complexity, correlated with a decrease in network coherence. This suggests that changes in cortical complexity can occur within a single brain state dominated by slow oscillations, leading to higher complexity associated with consciousness.
Article
Astronomy & Astrophysics
Leon Ofman, Tongjiang Wang
Summary: In this study, a three-dimensional magnetohydrodynamic (MHD) model was used to simulate the excitation and dissipation of slow magnetosonic waves in hot flaring coronal loops based on observational data. The results showed significant leakage of the waves from the hot loops, with a small effect of viscous dissipation in cooler loops and more significant effects in hotter loops. These findings highlight the importance of nonlinear 3D MHD models in understanding the various wave couplings, damping, and viscous dissipation in hot flaring coronal loops.
ASTROPHYSICAL JOURNAL
(2022)
Article
Astronomy & Astrophysics
Fanxiaoyu Xia, Tongjiang Wang, Yang Su, Jie Zhao, Qingmin Zhang, Astrid M. Veronig, Weiqun Gan
Summary: We present a detailed analysis of a reflecting intensity perturbation in a large coronal loop, which appeared as a sloshing oscillation and lasted for one and a half periods. Through differential emission measures analysis and coronal seismology, we find that the local sound speed and propagation speed of the perturbation during the oscillation are consistent, and thermal conduction is the major damping mechanism of the wave. Additionally, a wave-induced nanoflare at the remote footpoint is observed for the first time.
ASTROPHYSICAL JOURNAL LETTERS
(2022)
Article
Astronomy & Astrophysics
A. Alharbi, I Ballai, V Fedun, G. Verth
Summary: The study investigates the slow sausage waves in the solar atmosphere using a two-fluid model, focusing on the interaction between charged particles and neutrals. Results show that waves associated with charged particles are affected by gravitational stratification, while waves associated with neutrals are affected by wavelength.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Review
Biochemistry & Molecular Biology
Michela Rossini, Paola Pizzo, Riccardo Filadi
Summary: The strategic importance of inter-organelle cross-talk in regulating physiological cellular mechanisms is well established. Efforts have been made to study these organelle interactions and understand their functional roles within the cell. The available methods for investigating membrane contact sites have both advantages and disadvantages.
Article
Cell Biology
Riccardo Filadi, Elisa Greotti
Summary: Mitochondria play crucial roles in cellular activities by orchestrating diverse cell signaling pathways, with Ca2+ being one of the most significant targets. Understanding the role of mitochondrial Ca2+ signaling in physiological and pathological processes can provide insights into cellular functions and disease mechanisms. Specifically, investigating mitochondrial Ca2+ alterations in various pathological conditions, such as Alzheimer's disease, highlights the pivotal role of mitochondria in pathology.
Article
Cell Biology
Michela Rossini, Paloma Garcia-Casas, Riccardo Filadi, Paola Pizzo
Summary: Presenilin 2 (PS2) is a key protein linked to familial Alzheimer's disease (FAD) and plays a role in modulating various processes on signaling hubs such as the endoplasmic reticulum (ER) and mitochondria-associated membranes (MAM). Mutations in PS2 affect ER-mitochondria tethering and Ca2+ crosstalk, contributing to AD pathogenesis. Developing tools to target specific domains of PS2 may help counteract FAD-related cellular alterations.
Article
Cell Biology
Alessandro Leparulo, Marta Bisio, Nelly Redolfi, Tullio Pozzan, Stefano Vassanelli, Cristina Fasolato
Summary: This study compares the spontaneous brain electrical activity in AD and WT mice to investigate the specific features of AD and the effects of aging. The findings suggest that AD features can appear in young AD mice before plaque deposition, and aging characteristics can occur prematurely in young AD mice. These findings are important for understanding the pathogenesis of AD and the impact of aging.
Article
Biochemistry & Molecular Biology
Filippo Fornasiero, Cristina Scapin, Maurizio Vitadello, Paola Pizzo, Luisa Gorza
Summary: This study reveals the role of Grp94/gp96 in cytoprotection by regulating SERCA2 and improving Ca2+ homeostasis. It demonstrates that Grp94 can co-immunoprecipitate with non-client proteins and form a multiprotein complex involving active nNOS, contributing to antioxidant cytoprotection. Moreover, in breast cancer cells, the presence of Grp94-nNOS, SERCA2, and PMCA co-immunoprecipitation is associated with increased oxidant-induced apoptosis.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2022)
Article
Neurosciences
Horst Petschenig, Marta Bisio, Marta Maschietto, Alessandro Leparulo, Robert Legenstein, Stefano Vassanelli
Summary: Spike-based neuromorphic hardware shows great potential for low-energy brain-machine interfaces and exhibits high classification performance, while being insensitive to the recorded signal type and network state.
FRONTIERS IN NEUROSCIENCE
(2022)
Editorial Material
Cell Biology
Riccardo Filadi, Paola Pizzo
Article
Cell Biology
Lucia Barazzuol, Domenico Cieri, Nicola Facchinello, Tito Cali, Philip Washbourne, Francesco Argenton, Paola Pizzo
Summary: This study generated a zebrafish line with a psen2 knockout, and found that the absence of the protein does not significantly affect Notch signaling, but leads to an exaggeration of locomotor response, a decrease in ER-mitochondria contacts, and an increase in basal autophagy. The protein also plays a role in mitochondrial axonal transport, and its downregulation reduces organelle flux in zebrafish sensory neurons. These findings highlight zebrafish as a valuable model organism for studying PS2 functions and testing potential therapies for Alzheimer's disease.
Article
Multidisciplinary Sciences
Annamaria Lia, Gabriele Sansevero, Angela Chiavegato, Miriana Sbrissa, Diana Pendin, Letizia Mariotti, Tullio Pozzan, Nicoletta Berardi, Giorgio Carmignoto, Cristina Fasolato, Micaela Zonta
Summary: This study reveals that decreased calcium activity in astrocytes is associated with memory loss in a mouse model of Alzheimer's disease. Overexpression of STIM1 can restore calcium signaling and synaptic plasticity in astrocytes.
NATURE COMMUNICATIONS
(2023)
Article
Geriatrics & Gerontology
Diana Pendin, Cristina Fasolato, Emy Basso, Riccardo Filadi, Elisa Greotti, Luisa Galla, Chiara Gomiero, Alessandro Leparulo, Nelly Redolfi, Elena Scremin, Nicola Vajente, Tullio Pozzan, Paola Pizzo
Summary: Alzheimer's disease is a common cause of dementia in the elderly, with familial and non-familial cases. Studies focusing on the Aβ pathway have not been successful in modifying disease progression, indicating the presence of other pathogenic mechanisms such as Ca2+ dysregulation.
AGING CLINICAL AND EXPERIMENTAL RESEARCH
(2021)