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This review summarizes the presentations given at the 22nd International conference on Emerging Infectious Diseases in the Pacific Rim. The purpose of this annual meeting is to foster international collaborations and address important public health issues in the Asia-Pacific region. This meeting was held in Bangkok in February 2020 and focused on emerging virus infections. Unexpectedly, the SARS-CoV-2 pandemic was in the initial stages leading to a special session on COVID-19 in addition to talks on dengue, influenza, hepatitis, AIDS, Zika, chikungunya, rabies, cervical cancer and nasopharyngeal carcinoma. • Early recognition and response to SARS-CoV-2 entry into Thailand and Cambodia. • Pathogenesis of HIV, rabies, Lassa, chikungunya, coronavirus and paramyxovirus. • Improved diagnosis and treatment for norovirus, HBV and EBV infections. • Vaccine development for influenza, dengue, HIV, HCV and mosquito-borne pathogens. • Successful control of human papillomavirus infection through vaccination. [ABSTRACT FROM AUTHOR]

Abstract: The millimeter- and submillimeter-wave spectra of PtS in the state were observed by employing a source-modulated microwave spectrometer. The PtS radical was generated in a free space cell by using a dc glow plasma of H2S and Ar. Platinum atoms were supplied from a small piece of platinum sheet lining the inner surface of a stainless steel cathode by the sputtering reaction. Rotational transitions were recorded for four dominant isotopomers, 194PtS, 195PtS, 196PtS, and 198PtS in the ground state, and the spectroscopic constants for each isotopomer were determined using a Hund’s case (c) Hamiltonian. The lower limit of the energy separation is estimated from a Hund’s case (a) analysis. [Copyright &y& Elsevier]

Tob, a member of the Tob and BTG antiproliferative protein family, plays an important role in many cellular processes including cell proliferation. In this study, we have addressed molecular mechanisms regulating subcellular localization of Tob. Treatment with leptomycin B, an inhibitor of nuclear export signal (NES) receptor, resulted in a change in subcellular distribution of Tob from its pan-cellular distribution to nuclear accumulation, indicating the existence of NES in Tob. Our results have then identified an N-terminal region (residues 2–14) of Tob as a functional NES. They have also shown that Tob has a functional, bipartite nuclear localization signal (NLS) in residues 18–40. Thus, Tob is shuttling between the nucleus and the cytoplasm by its NES and NLS. To examine a possible relationship between subcellular distribution of Tob and its function, we exogenously added a strong NLS sequence or a strong NES sequence or both to Tob. The obtained results have demonstrated that the strong NLS-added Tob has a much weaker activity to inhibit cell cycle progression from G0/G1 to S phase. These results suggest that cytoplasmic localization or nucleocytoplasmic shuttling is important for the antiproliferative function of Tob. [Copyright &y& Elsevier]

Lipid metabolism is one of energy metabolic pathways that produce adenosine triphosphate (ATP). In this pathway, lysosomal acid lipase (LAL) encoded by Lipase A (LIPA), plays an important role in catalyzing lipids to fatty acids (FAs), which drive oxidative phosphorylation (OXPHOS) and generate ATP. Previously, we found that a LIPA single nucleotide polymorphism rs143793106, which decreases the LAL activity, suppressed the cytodifferentiation of human periodontal ligament (HPDL) cells. However, the mechanisms underlying that suppression are still not fully clarified. Thus, we aimed to investigate the mechanisms regulating the cytodifferentiation of HPDL cells by LAL in terms of energy metabolism. We performed the osteogenic induction of HPDL cells with or without Lalistat-2, a LAL inhibitor. To visualize lipid droplet (LD) utilization, we performed confocal microscopy on HPDL cells. We also performed real-time PCR to analyze the gene expression of calcification-related and metabolism-related genes. Furthermore, we measured the ATP production rate from two major energy production pathways, OXPHOS and glycolysis, and OXPHOS-related parameters of HPDL cells during their cytodifferentiation. We found that LDs were utilized during the cytodifferentiation of HPDL cells. Alkaline phosphatase (ALPL), collagen type 1 alpha 1 chain (COL1A1), ATP synthase F1 subunit alpha (ATP5F1A), and carnitine palmitoyltransferase 1A (CPT1A) mRNA expressions were upregulated, whereas lactate dehydrogenase A (LDHA) mRNA expression was downregulated. Additionally, total ATP production rate was significantly increased. In contrast, in the presence of Lalistat-2, LD utilization was inhibited and ALPL , COL1A1 , and ATP5F1A mRNA expression was downregulated. Additionally, ATP production rate and spare respiratory capacity of the OXPHOS pathway were decreased in HPDL cells during their cytodifferentiation. Collectively, the defect of LAL in HPDL cells decreased LD utilization and OXPHOS capacity, resulting in reduced energy to sustain the adequate ATP production required for the cytodifferentiation of HPDL cells. Thus, LAL is important for periodontal tissue homeostasis as a regulator of bioenergetic process of HPDL cells. [Display omitted] • LAL inhibition by Lalistat-2 suppressed the cytodifferentiation of HPDL cells. • LAL was involved in energy metabolism during HPDL cytodifferentiation. • LAL inhibition reduced spare respiratory capacity during HPDL cytodifferentiation. [ABSTRACT FROM AUTHOR]

The rotational spectrum of the AgS radical in the X 2 Π i state was observed using a source-modulation microwave spectrometer. This radical was generated in a free-space cell by a DC glow discharge under Ar-diluted H 2 S. Silver atoms were supplied by sputtering from silver sheets placed on the inner surface of the stainless steel cathode. Rotational transitions from J = 7.5 – 6.5 to 39.5 – 38.5 were measured in the 58–310 GHz region. Rotational, centrifugal distortion, and several fine- and hyperfine-structure constants were determined by least-squares analysis. Other spectroscopic parameters such as the dissociation energy, vibrational wavenumber, and equilibrium bond length were also derived from the determined molecular constants. In addition, some electronic properties were estimated from the fine- and hyperfine-structure constants. [ABSTRACT FROM AUTHOR]

Isolation of antigen (Ag)-specific T cells is an important step in the investigation of T-cell immunity. Activation-induced markers (AIMs), such as CD154/tumor necrosis factor (TNF)/CD107A/CD134/CD137 enable the sorting of Ag-specific T cells without using human leukocyte antigen (HLA)-multimers. However, optimal conditions suitable for simultaneous detection of both Ag-specific CD4 and CD8 T cells have not been investigated. Here, conditions were optimized to simultaneously detect the maximum number of activated CD4 and CD8 T cells in a TCR-dependent manner. First, the frequency of total pools of AIM-positive cells induced by superantigen, staphylococcal enterotoxin B (SEB), stimulation in various culture conditions was monitored and compared side-by-side. The total amount of AIM-positive CD4 T cells, but not CD8 T cells, was significantly abrogated by addition of brefeldin A. TNF-alpha converting enzyme inhibitor treatment effectively increased the TNF-positive population, without affecting other markers' positivity. AIM-positive CD4 T cells and CD8 T cells were detected at least 3 h after stimulation. Furthermore, examination of the multiple combination of each marker revealed that minimum contribution of CD134 on the total pool of AIM-positive cells at this setting, suggesting the essential and non-essential AIMs to maximize the detected number of AIM-positive cells. Taken together, this optimized method will be a useful tool for the simultaneous monitoring the T-cell receptor stimulation-dependent activation of CD4 and CD8 T cells using inducible markers on the cell surface including Ag-specific T cells. [Display omitted] • CD154/TNF/CD134/CD137 combination boosts the detected the AIM-positive CD4 T cells pool. • CD107A/TNF/CD134/CD137 combination boosts the detected the AIM-positive CD8 T cells pool. • This method simultaneously detects human PBMC AIM-positive CD4 and CD8 T cells during short period after stimulation. • CD154/CD107A/TNF/CD137 combination enable us to detect nearly 100% of AIM-positive CD4 T cells and CD8 T cells. [ABSTRACT FROM AUTHOR]

ES cell (ESC) identity is stably maintained through the coordinated regulation of transcription factors and chromatin structure. SMARCB1, also known as INI1, SNF5, BAF47, is one of the subunits of SWI/SNF (BAF) complexes that play a crucial role in regulating gene expression by controlling chromatin dynamics. Genetic ablation of Smarcb1 in mice leads to embryonic lethality at the peri-implantation stage, indicating that Smarcb1 is important for the early developmental stages. However, the role of SMARCB1 in the maintenance of the ESC identity remains unknown. Here we established mouse ESCs lacking Smarcb1 and investigated the effect of Smarcb1 ablation on the differentiation propensity of ESCs. We found an increased expression of trophectoderm-related genes including Cdx2 in Smarcb1 -deficient ESCs. Consistently, they exhibited an extended differentiation propensity into the trophectoderm lineage cells in teratomas. However, although Smarcb1 -deficient cells were infrequently incorporated into the trophectoderm cell layer of blastocysts, they failed to contribute to mature placental tissues in vivo. Furthermore, Smarcb1 -deficient cells exhibited a premature differentiation in the neural tissue of E14.5 chimeric embryos. Notably, we found that binding motifs for CTCF, which is involved in the maintenance of genomic DNA architecture was significantly enriched in chromatin regions whose accessibility was augmented in Smarcb1 -deficient cells, while those for pluripotency factors were overrepresented in regions which have more closed structure in those cells. Collectively, we propose that SMARCB1-mediated remodeling of chromatin landscapes is important for the maintenance and differentiation of ESCs. • Smarcb1 -deficient ES cells exhibit an increased expression of trophectoderm-related genes including Cdx2. • Smarcb1 -deficient ES cells retain pluripotency but exhibit an impaired differentiation in vivo. • SMARCB1-mediated remodeling of chromatin landscapes may be important for the maintenance and differentiation of ESCs. [ABSTRACT FROM AUTHOR]

Abstract: It is well known that calcium ions (Ca2+) induce keratinocyte differentiation. Ca2+ distributes to form a vertical gradient that peaks at the stratum granulosum. It is thought that the stratum corneum (SC) forms the Ca2+ gradient since it is considered the only permeability barrier in the skin. However, the epidermal tight junction (TJ) in the granulosum has recently been suggested to restrict molecular movement to assist the SC as a secondary barrier. The objective of this study was to clarify the contribution of the TJ to Ca2+ gradient and epidermal differentiation in reconstructed human epidermis. When the epidermal TJ barrier was disrupted by sodium caprate treatment, Ca2+ flux increased and the gradient changed in ion-capture cytochemistry images. Alterations of ultrastructures and proliferation/differentiation markers revealed that both hyperproliferation and precocious differentiation occurred regionally in the epidermis. These results suggest that the TJ plays a crucial role in maintaining epidermal homeostasis by controlling the Ca2+ gradient. [Copyright &y& Elsevier]

Abstract: Carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) regulates intestinal immunological homeostasis. However, precise expression patterns of CEACAM1 isoforms remain poorly understood in the intestinal epithelia. Focusing on the small intestinal epithelium of BALB/c mice, we identified three novel splice variants encoding CEACAM1a-2, -2C1, and -4C1 by RT-PCR. CEACAM1a-2, -2C1, and -4C1 demonstrated secretory properties by transfection experiments in vitro. Among them, CEACAM1a-4C1 was the major secreted isoform in vivo due to the soluble/secreted CEACAM1a with a frameshift sequence in the C-terminus, specific for CEACAM1a-2C1 and -4C1. CEACAM1a-4C1 was capable of binding murine hepatitis virus (MHV) and was detected at approximately 120kDa in the small intestinal secretions. Neutralizing effects of the soluble CEACAM1a on MHV infectivity in vitro were demonstrated by using recombinant CEACAM1a-4C1. Our data suggest an intrinsic mechanism operated by free CEACAM1 for surveillance of pathogens and maintenance of homeostasis in the intestine. [Copyright &y& Elsevier]

Abstract: Tight junctions (TJs) restrict paracellular flux of water and solutes in epithelia and endothelia. In epidermis, the physiological role of TJs is not fully understood. In this study, sodium caprate (C10), which dilates intestinal TJs, was applied to cultured human epidermal keratinocytes and reconstructed human epidermis to investigate the effects of C10 on epidermal TJs. C10 treatment decreased transepithelial electrical resistance and increased paracellular permeability, although Western blots showed that the expression of TJ-related transmembrane proteins was not decreased. The effects of C10 were reversible. Immunofluorescence microscopy and immuno-replica electron microscopy showed that the localization of TJ strands were disintegrated, concomitant with the dispersion and/or disappearance of TJ-related molecules from the cell surface. These findings suggest that C10 impairs barrier function by physically disrupting TJ conformation in the epidermis. Furthermore, these results also show that proper localization of the molecules on the cellular membrane is important for TJ barrier function. [Copyright &y& Elsevier]