Dynamic and stable hippocampal representations of social identity and reward expectation support associative social memory in male mice.

Recognizing an individual and retrieving and updating the value information assigned to the individual are fundamental abilities for establishing social relationships. To understand the neural mechanisms underlying the association between social identity and reward value, we developed Go-NoGo social discrimination paradigms that required male subject mice to distinguish between familiar mice based on their individually unique characteristics and associate them with reward availability. We found that mice could discriminate individual conspecifics through a brief nose-to-nose investigation, and this ability depended on the dorsal hippocampus.

Internet of medical things-based real-time digital health service for precision medicine: Empirical studies using MEDBIZ platform.

The aim of this study was to introduce the implemented MEDBIZ platform based on the internet of medical things (IoMT) supporting real-time digital health services for precision medicine. In addition, we demonstrated four empirical studies of the digital health ecosystem that could provide real-time healthcare services based on IoMT using real-world data from in-hospital and out-hospital patients. Implemented MEDBIZ platform based on the IoMT devices and big data to provide digital healthcare services to the enterprise and users.

Concept and Proof of the Lifelog Bigdata Platform for Digital Healthcare and Precision Medicine on the Cloud.

Purpose: We propose the Lifelog Bigdata Platform as a sustainable digital healthcare system based on individual-centric lifelog datasets and describe the standardization of lifelog and clinical data in its full-cycle management system.

Materials And Methods: The Lifelog Bigdata Platform was developed by Yonsei Wonju Health System on the cloud to support digital healthcare and precision medicine. It consists of five core components: data acquisition system, de-identification of individual information, lifelog integration, analyzer, and service.

AI-Enabled Algorithm for Automatic Classification of Sleep Disorders Based on Single-Lead Electrocardiogram.

Healthy sleep is an essential physiological process for every individual to live a healthy life. Many sleep disorders both destroy the quality and decrease the duration of sleep. Thus, a convenient and accurate detection or classification method is important for screening and identifying sleep disorders.

Inter-spike mitochondrial Ca release enhances high frequency synaptic transmission.

Key Points: Presynaptic mitochondria not only absorb but also release Ca during high frequency stimulation (HFS) when presynaptic [Ca ] is kept low (<500 nm) by high cytosolic Ca buffer or strong plasma membrane calcium clearance mechanisms under physiological external [Ca ]. Mitochondrial Ca release (MCR) does not alter the global presynaptic Ca transients. MCR during HFS enhances short-term facilitation and steady state excitatory postsynaptic currents by increasing vesicular release probability.

Bidirectional Signaling of Neuregulin-2 Mediates Formation of GABAergic Synapses and Maturation of Glutamatergic Synapses in Newborn Granule Cells of Postnatal Hippocampus.

Unlabelled: Expression of neuregulin-2 (NRG2) is intense in a few regions of the adult brain where neurogenesis persists; however, little is understood about its role in developments of newborn neurons. To study the role of NRG2 in synaptogenesis at different developmental stages, newborn granule cells in rat hippocampal slice cultures were labeled with retrovirus encoding tetracycline-inducible microRNA targeting NRG2 and treated with doxycycline (Dox) at the fourth or seventh postinfection day (dpi). The developmental increase of GABAergic postsynaptic currents (GPSCs) was suppressed by the early Dox treatment (4 dpi), but not by late treatment (7 dpi).

Ca(2+) clearance by plasmalemmal NCLX, Li(+)-permeable Na(+)/Ca(2+) exchanger, is required for the sustained exocytosis in rat insulinoma INS-1 cells.

Na(+)/Ca(2+) exchangers are key players for Ca(2+) clearance in pancreatic β-cells, but their molecular determinants and roles in insulin secretion are not fully understood. In the present study, we newly discovered that the Li(+)-permeable Na(+)/Ca(2+) exchangers (NCLX), which were known as mitochondrial Na(+)/Ca(2+) exchangers, contributed to the Na(+)-dependent Ca(2+) movement across the plasma membrane in rat INS-1 insulinoma cells. Na(+)/Ca(2+) exchange activity by NCLX was comparable to that by the Na(+)/Ca(2+) exchanger, NCX.

Kv1.2 mediates heterosynaptic modulation of direct cortical synaptic inputs in CA3 pyramidal cells.

Key Points: We investigated the cellular mechanisms underlying mossy fibre-induced heterosynaptic long-term potentiation of perforant path (PP) inputs to CA3 pyramidal cells. Here we show that this heterosynaptic potentiation is mediated by downregulation of Kv1.2 channels.

Costimulation of AMPA and metabotropic glutamate receptors underlies phospholipase C activation by glutamate in hippocampus.

Glutamate, a major neurotransmitter in the brain, activates ionotropic and metabotropic glutamate receptors (iGluRs and mGluRs, respectively). The two types of glutamate receptors interact with each other, as exemplified by the modulation of iGluRs by mGluRs. However, the other way of interaction (i.

Activity-dependent downregulation of D-type K+ channel subunit Kv1.2 in rat hippocampal CA3 pyramidal neurons.

The intrinsic excitability of neurons plays a critical role in the encoding of memory at Hebbian synapses and in the coupling of synaptic inputs to spike generation. It has not been studied whether somatic firing at a physiologically relevant frequency can induce intrinsic plasticity in hippocampal CA3 pyramidal cells (CA3-PCs). Here, we show that a conditioning train of 20 action potentials (APs) at 10 Hz causes a persistent reduction in the input conductance and an acceleration of the AP onset time in CA3-PCs, but not in CA1-PCs.

Leptin promotes K(ATP) channel trafficking by AMPK signaling in pancreatic β-cells.

Leptin is a pivotal regulator of energy and glucose homeostasis, and defects in leptin signaling result in obesity and diabetes. The ATP-sensitive potassium (K(ATP)) channels couple glucose metabolism to insulin secretion in pancreatic β-cells. In this study, we provide evidence that leptin modulates pancreatic β-cell functions by promoting K(ATP) channel translocation to the plasma membrane via AMP-activated protein kinase (AMPK) signaling.

Endocytosis of somatodendritic NCKX2 is regulated by Src family kinase-dependent tyrosine phosphorylation.

We have previously reported that the surface expression of K(+)-dependent Na(+)/Ca(2+) exchanger 2 (NCKX2) in the somatodendritic compartment is kept low by constitutive endocytosis, which results in the polarization of surface NCKX2 to the axon. Clathrin-mediated endocytosis is initiated by interaction of the μ subunit of adaptor protein complex 2 (AP-2) with the canonical tyrosine motif (YxxΦ) of a target molecule. We examined whether endocytosis of NCKX2 involves two putative tyrosine motifs ((365)YGKL and (371)YDTM) in the cytoplasmic loop of NCKX2.

KIF21A-mediated axonal transport and selective endocytosis underlie the polarized targeting of NCKX2.

We have previously shown that K(+)-dependent Na(+)/Ca(2+) exchanger (NCKX) is a major calcium clearance mechanism at the large axon terminals of central neurons, whereas their somata display little NCKX activity. We investigated mechanisms underlying the axonal polarization of NCKX2 in rat hippocampal neurons. We identified NCKX2 as the first neuron-specific cargo molecule of kinesin family member 21A (KIF21A).

Target cell-specific involvement of presynaptic mitochondria in post-tetanic potentiation at hippocampal mossy fiber synapses.

Previous studies indicate that boutons from the same axon exhibit distinct Ca2+ dynamics depending on the postsynaptic targets. Mossy fibers of hippocampal granule cells innervate synaptic targets via morphologically distinct boutons. We investigated mitochondrial involvement in the generation of post-tetanic residual Ca2+ (Ca(res)) at large and small en passant mossy fiber boutons (MFBs).

A new cytotoxic prenylated chalcone from Sophora flavescens.

We have isolated a new prenylated chalcone from the roots of Sophora flavescens (Leguminosae). We determined that structure of this compound is 7,9,2',4'-tetrahydroxy-8-isopentenyl-5-methoxychalcone (1) on the basis of spectroscopic analysis (1D and 2D NMR data). Compound 1 exhibited potent cytotoxicity against human acute promyelocytic (HL60), mouse lymphocytic (L1210) and human histiocytic (U937) leukemia cells.

Protein kinase C-dependent enhancement of activity of rat brain NCKX2 heterologously expressed in HEK293 cells.

Different members of the Na+/Ca2++K+ exchanger (NCKX) family are present in distinct brain regions, suggesting that they may have cell-specific functions. Many neuronal channels and transporters are regulated via phosphorylation. Regulation of the rat brain NCKXs by protein kinases, however, has not been described.

Secretory low molecular weight phospholipase A2 plays important roles in cell elongation and shoot gravitropism in Arabidopsis.

To elucidate the cellular functions of phospholipase A(2) in plants, an Arabidopsis cDNA encoding a secretory low molecular weight phospholipase A(2) (AtsPLA(2)beta) was isolated. Phenotype analyses of transgenic plants showed that overexpression of AtsPLA(2)beta promotes cell elongation, resulting in prolonged leaf petioles and inflorescence stems, whereas RNA interference-mediated silencing of AtsPLA(2)beta expression retards cell elongation, resulting in shortened leaf petioles and stems. AtsPLA(2)beta is expressed in the cortical, vascular, and endodermal cells of the actively growing tissues of inflorescence stems and hypocotyls.