Analysis of the incidence of influenza before and after the COVID-19 pandemic in South Korea.

Objectives: Influenza outbreaks of varying size occur every year, but during the COVID-19 pandemic, many countries experienced influenza at lower levels. However, following the relaxation of COVID-19 prevention measures in 2022, the incidence of influenza began to increase gradually. Thus, this study compared the occurrence of influenza from week 36 of 2017, before the COVID-19 outbreak, until 2023.

The evolutionary and genetic patterns of African swine fever virus.

African swine fever (ASF) is a serious animal disease, and has spread to Africa, Europe and Asia, causing massive economic losses. African swine fever virus (ASFV) is transmitted from a reservoir host (warthog) to domestic pigs via a sylvatic cycle (transmission between warthogs and soft ticks) and a domestic cycle (transmission between domestic pigs) and survives by expressing a variety of genes related to virus-host interactions. We evaluated differences in codon usage patterns among ASFV genotypes and clades and explored the common and specific evolutionary and genetic characteristics of ASFV sequences.

Utilization of systematic error-assessment software to improve phylogenetic accuracy.

Unlike classical systems based on the use of morphological data, modern phylogenetic analyses use genetic information to construct phylogenetic trees. Ongoing research in the field of phylogenetics is evaluating the accuracy of phylogenetic estimation results and the reliability of phylogenetic trees to explain evolutionary relationships. Recently, the probability of stochastic errors in large-scale phylogenetic datasets has decreased, while the probability of systematic errors has increased.

Preparation of human astrocytes with potent therapeutic functions from human pluripotent stem cells using ventral midbrain patterning.

Introduction: Astrocytes are glial-type cells that protect neurons from toxic insults and support neuronal functions and metabolism in a healthy brain. Leveraging these physiological functions, transplantation of astrocytes or their derivatives has emerged as a potential therapeutic approach for neurodegenerative disorders.

Methods: To substantiate the clinical application of astrocyte-based therapy, we aimed to prepare human astrocytes with potent therapeutic capacities from human pluripotent stem cells (hPSCs).

TRPC4 deletion elicits behavioral defects in sociability by dysregulating expression of microRNA-138-2.

To investigate whether the defects in transient receptor potential canonical 4 (TRPC4), which is strongly expressed in the hippocampus, are implicated in ASD, we examined the social behaviors of mice in which was deleted (). mice displayed the core symptoms of ASD, namely, social disability and repetitive behaviors. In microarray analysis of the hippocampus, microRNA (miR)-138-2, the precursor of miR-138, was upregulated in mice.

Dialdehyde modification of laminarin for facile synthesis of ultrafine silver nanoparticles with excellent antibacterial and wound healing properties.

Laminarin is a promising marine biopolymer that is abundant, non-toxic, and biodegradable. However, laminarin has a weak reduction potential for metal ions, resulting in the synthesis of a lower content of large-sized silver nanoparticles (AgNPs). Here, we showed that after the introduction of aldehyde groups, the reduction potential of laminarin increased, decreasing the synthesis time and increasing the density of AgNPs.

Analysis of evolutionary and genetic patterns in structural genes of primate lentiviruses.

Background: Primate lentiviruses (HIV1, HIV2, and Simian immunodeficiency virus [SIV]) cause immune deficiency, encephalitis, and infectious anemia in mammals such as cattle, cat, goat, sheep, horse, and puma.

Objective: This study was designed and conducted with the main purpose of confirming the overall codon usage pattern of primate lentiviruses and exploring the evolutionary and genetic characteristics commonly or specifically expressed in HIV1, HIV2, and SIV.

Methods: The gag, pol, and env gene sequences of HIV1, HIV2, and SIV were analyzed to determine their evolutionary relationships, nucleotide compositions, codon usage patterns, neutrality, selection pressure (influence of mutational pressure and natural selection), and viral adaptation to human codon usage.

Autistic-like social deficits in hippocampal MeCP2 knockdown rat models are rescued by ketamine.

Autism or autism spectrum disorder (ASD) is a behavioral syndrome characterized by persistent deficits in social interaction, and repetitive patterns of behavior, interests, or activities. The gene encoding Methyl-CpG binding protein 2 (MeCP2) is one of a few exceptional genes of established causal effect in ASD. Although genetically engineered mice studies may shed light on how MeCP2 loss affects synaptic activity patterns across the whole brain, such studies are not considered practical in ASD patients due to the overall level of impairment, and are technically challenging in mice.

LGI1 governs neuritin-mediated resilience to chronic stress.

Depression is accompanied by neuronal atrophy and decreased neuroplasticity. Leucine-rich glioma-inactivated protein 1 (LGI1), a metastasis suppressor, plays an important role in the development of CNS synapses. We found that LGI1 expression was reduced in the hippocampi of mice that underwent chronic unpredictable stress (CUS), and could be rescued by the antidepressant, fluoxetine.

SGK1 inhibition in glia ameliorates pathologies and symptoms in Parkinson disease animal models.

Astrocytes and microglia are brain-resident glia that can establish harmful inflammatory environments in disease contexts and thereby contribute to the progression of neuronal loss in neurodegenerative disorders. Correcting the diseased properties of glia is therefore an appealing strategy for treating brain diseases. Previous studies have shown that serum/ glucocorticoid related kinase 1 (SGK1) is upregulated in the brains of patients with various neurodegenerative disorders, suggesting its involvement in the pathogenesis of those diseases.

Analysis of protein determinants of host-specific infection properties of polyomaviruses using machine learning.

Background: The large tumor antigen (LT-Ag) and major capsid protein VP1 are known to play important roles in determining the host-specific infection properties of polyomaviruses (PyVs).

Objective: The objective of this study was to investigate the physicochemical properties of amino acids of LT-Ag and VP1 that have important effects on host specificity, as well as classification techniques used to predict PyV hosts.

Methods: We collected and used reference sequences of 86 viral species for analysis.

Comparative analysis of codon usage patterns in Rift Valley fever virus.

Rift Valley fever virus (RVFV) is a vector-borne pathogen and is the most widely known virus in the genus Phlebovirus. Since it was first reported, RVFV has spread to western Africa, Egypt and Madagascar from its traditional endemic region, and infections continue to occur in new areas. In this study, we analyzed genomic patterns according to the infection properties of RVFV.

Codon usage patterns of LT-Ag genes in polyomaviruses from different host species.

Background: Polyomaviruses (PyVs) have a wide range of hosts, from humans to fish, and their effects on hosts vary. The differences in the infection characteristics of PyV with respect to the host are assumed to be influenced by the biochemical function of the LT-Ag protein, which is related to the cytopathic effect and tumorigenesis mechanism via interaction with the host protein.

Methods: We carried out a comparative analysis of codon usage patterns of large T-antigens (LT-Ags) of PyVs isolated from various host species and their functional domains and sequence motifs.

Downregulation of SIRT2 by Chronic Stress Reduces Expression of Synaptic Plasticity-related Genes through the Upregulation of Ehmt2.

Silent information regulator 2 (Sirtuin2 / SIRT2) is a NAD-dependent deacetylase that regulates the cellular oxidative stress response. It modulates transcriptional silencing and protein stability through deacetylation of target proteins including histones. Previous studies have shown that SIRT2 plays a role in mood disorders and hippocampus-dependent cognitive function, but the underlying neurobiological mechanism is poorly understood.

Prediction of cross-species infection propensities of viruses with receptor similarity.

Studies of host factors that affect susceptibility to viral infections have led to the possibility of determining the risk of emerging infections in potential host organisms. In this study, we constructed a computational framework to estimate the probability of virus transmission between potential hosts based on the hypothesis that the major barrier to virus infection is differences in cell-receptor sequences among species. Information regarding host susceptibility to virus infection was collected to classify the cross-species infection propensity between hosts.

Analysis of the codon usage pattern of the RdRP gene of mycovirus infecting Aspergillus spp.

Background: Mycoviruses that infect fungi generally do not have a significant effect on the host and, instead, reduce the toxicity of the fungi. However, recent studies have shown that polymycovirus-1, a mycovirus that infects Aspergillus species known to cause disease in humans, is related to increased virulence of the fungus.

Methods: Comparative analysis was performed of RdRP gene codon usage patterns of Aspergillus fumigatus polymycovirus-1 (AfuPmV-1) and other mycoviruses known to infect Aspergillus spp.

Transient receptor potential melastatin 2 governs stress-induced depressive-like behaviors.

Major depressive disorder (MDD) is a devastating disease that arises in a background of environmental risk factors, such as chronic stress, that produce reactive oxygen species (ROS) in the brain. The chronic stress-induced ROS production involves Ca signals; however, the mechanism is poorly understood. Transient receptor potential melastatin type 2 (TRPM2) is a Ca-permeable cation channel that is highly expressed in the brain.

Simulation Model of Bacterial Resistance to Antibiotics Using Individual-Based Modeling.

We designed and implemented simulation models of bacterial growth and antibiotic resistance to determine the appropriate antibiotics to use against antibiotic-resistant bacteria. Simulation models were designed using individual-based modeling, and a simulation tool, ARSim, was developed to conduct experiments using the models. Simulations of bacterial growth were conducted by virtually growing Klebsiella pneumoniae bacteria in a virtual environment with predefined parameters.

The antidepressant action of 3-(2-carboxypiperazin-4-yl)propyl-1-phosphonic acid is mediated by phosphorylation of histone deacetylase 5.

3-(2-Carboxypiperazin-4-yl)propyl-1-phosphonic acid (CPP), a competitive N-methyl-D-aspartate (NMDA) receptor antagonist, produces rapid antidepressant-like effects in animal models of depression. However, the molecular mechanisms underlying these behavioral actions remain unknown. Here, we demonstrate that CPP rapidly stimulates histone deacetylase (HDAC) 5 phosphorylation and nuclear export in rat hippocampal neurons.

Capsaicin upregulates HDAC2 via TRPV1 and impairs neuronal maturation in mice.

Transient receptor potential vanilloid 1 (TRPV1) affects mood and neuroplasticity in the brain, where its role is poorly understood. In the present study we investigated whether capsaicin (8-methyl-N-vanillyl-trans-6-nonenamide), an agonist of TRPV1, induced chromatin remodeling and thereby altered gene expression related to synaptic plasticity. We found that capsaicin treatment resulted in upregulation of histone deacetylase 2 (HDAC2) in the mouse hippocampus and HDAC2 was enriched at Psd95, synaptophysin, GLUR1, GLUR2 promoters.

Role of Dorsal Striatum Histone Deacetylase 5 in Incubation of Methamphetamine Craving.

Background: Methamphetamine (meth) seeking progressively increases after withdrawal (incubation of meth craving). We previously demonstrated an association between histone deacetylase 5 (HDAC5) gene expression in the rat dorsal striatum and incubation of meth craving. Here we used viral constructs to study the causal role of dorsal striatum HDAC5 in this incubation.

Oleanolic Acid Promotes Neuronal Differentiation and Histone Deacetylase 5 Phosphorylation in Rat Hippocampal Neurons.

Oleanolic acid (OA) has neurotrophic effects on neurons, although its use as a neurological drug requires further research. In the present study, we investigated the effects of OA and OA derivatives on the neuronal differentiation of rat hippocampal neural progenitor cells. In addition, we investigated whether the class II histone deacetylase (HDAC) 5 mediates the gene expression induced by OA.

Ketamine induces brain-derived neurotrophic factor expression via phosphorylation of histone deacetylase 5 in rats.

Ketamine shows promise as a therapeutic agent for the treatment of depression. The increased expression of brain-derived neurotrophic factor (BDNF) has been associated with the antidepressant-like effects of ketamine, but the mechanism of BDNF induction is not well understood. In the current study, we demonstrate that the treatment of rats with ketamine results in the dose-dependent rapid upregulation of Bdnf promoter IV activity and expression of Bdnf exon IV mRNAs in rat hippocampal neurons.

TRPV1 Regulates Stress Responses through HDAC2.

Stress causes changes in neurotransmission in the brain, thereby influencing stress-induced behaviors. However, it is unclear how neurotransmission systems orchestrate stress responses at the molecular and cellular levels. Transient receptor potential vanilloid 1 (TRPV1), a non-selective cation channel involved mainly in pain sensation, affects mood and neuroplasticity in the brain, where its role is poorly understood.