• Biomedical Science Letters
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• v.21 no.3
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• pp.152-159
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• 2015

Der p 2, which is a major allergen of house dust mite, plays an important role in the pathogenesis of allergic disease. There is controversy regarding whether Der p 2 binds to Toll-like receptor 4 (TLR4), and its inflammatory effect has not yet been elucidated. In the current study, we examined the interaction of Der p 2 with TLR4 and the effect of Der p 2 on cytokine release in THP-1 cells and lymphocytes. Among house dust mite extracts, recombinant TLR4 protein interacted with Der p 2. The overall structure of Der p 2 is characteristic of the immunoglobulin superfamily and contains ten ${\beta}-strands$, forming a ${\beta}-cup$ fold with two anti-parallel ${\beta}-sheets$, and a short 310 helix. The two sheets can be separated, further allowing the formation of a large internal pocket, which is narrow and suitable for binding large flat molecules such as lipid-like molecules. Der p 2 caused increased secretion of IL-6, IL-8, and MCP-1, which are neutrophil survival factors, in human monocytic THP-1 cells in a time-dependent manner. Der p 2 also induces the release of cytokines in normal and allergic lymphocytes. Supernatant after treatment with Der p 2 inhibited neutrophil apoptosis. In coculture of lymphocytes with neutrophils, Der p 2 inhibited spontaneous apoptosis of allergic neutrophils. In summary, Der p 2 binds to TLR4 and induces an inflammatory response such as cytokine secretion in immune cells. These findings may enable elucidation of allergy pathogenesis by specific allergen of house dust mite.

• Journal of Gastric Cancer
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• v.22 no.4
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• pp.348-368
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• 2022

Purpose: Chromosomal instability is a hallmark of gastric cancer (GC). It can be driven by single nucleotide variants (SNVs) in cell cycle genes. We investigated the associations between SNVs in candidate genes, PLK2, PLK3, and ATM, and GC risk and clinicopathological features. Materials and Methods: The genotyping study included 542 patients with GC and healthy controls. Generalized linear models were used for the risk and clinicopathological association analyses. Survival analysis was performed using the Kaplan-Meier method. The binding of candidate miRs was analyzed using a luciferase reporter assay. Results: The PLK2 C_rs15009-C_rs963615 haplotype was under-represented in the GC group compared to that in the control group (P_corr=0.050). Male patients with the PLK2 rs963615 CT genotype had a lower risk of GC, whereas female patients had a higher risk (P=0.023; P=0.026). The PLK2 rs963615 CT genotype was associated with the absence of vascular invasion (P=0.012). The PLK3 rs12404160 AA genotype was associated with a higher risk of GC in the male population (P=0.015). The ATM T_rs228589-A_rs189037-G_rs4585 haplotype was associated with a higher risk of GC (P<0.001). The ATM rs228589, rs189037, and rs4585 genotypes TA+AA, AG+GG, and TG+GG were associated with the absence of perineural invasion (P=0.034). In vitro analysis showed that the cancer-associated miR-23b-5p mimic specifically bound to the PLK2 rs15009 G allele (P=0.0097). Moreover, low miR-23b expression predicted longer 10-year survival (P=0.0066) in patients with GC. Conclusions: PLK2, PLK3, and ATM SNVs could potentially be helpful for the prediction of GC risk and clinicopathological features. PLK2 rs15009 affects the binding of miR-23b-5p. MiR-23b-5p expression status could serve as a prognostic marker for survival in patients with GC.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.12
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• pp.1147-1153
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• 2010

To evaluate the solar photocatalytic degradation efficiency of chloroform in a real solar-light driven compound parabolic concentrators (CPCs) system, $TiO_2$ was irradiated with a metalhalide lamp (1000 W), which has a similar wavelength to sunlight. The results were applied to a pilot scale reactor system by converting the data to a standardized illumination time. In addition, the effects of initial pH and the $TiO_2$ dose on the photocatalytic degradation of chloroform were investigated. The results were compared with the specific surface area (S.S.A) and particle size of $TiO_2$, which changed according to the pH, to determine the relationship between the S.S.A, particle size and the photocatalytic degradation of chloroform. The experiment was carried out at pH 4~7 using 0.1, 0.2, 0.4 g/L of $TiO_2$. The particle size and specific surface area of $TiO_2$ were measured. There was no significant difference between the variables. However, pH affects the particle size distribution and specific surface area of $TiO_2$. Inaddition, the activation of a photocatalyst did not show a linear relationship with the specific surface area of $TiO_2$ in the photocatalytic degradation of chloroform.

• Microbiology and Biotechnology Letters
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• v.49 no.1
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• pp.120-129
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• 2021

Rotavirus A (RVA) is recognized as a major etiology responsible for the development of acute gastroenteritis in children worldwide. The purpose of the present study was to perform the molecular characterization of RVA. A total of 323 stool specimens collected from hospitalized children with acute gastroenteritis in Chiang Rai, Thailand, in 2016-2018 were identified for G- and P-genotypes through RT-PCR analysis. RVA was more prevalent in 2017-2018 (37.8%) than in 2016-2017 (23.2%). The seasonal peak of RVA occurred from March to April. G3P[8] was predominant in 2016-2017 (90.6%) and 2017-2018 (58.6%). Other genotypes including G1P[8], G8P[8], G9P[8], and mixed infections were also identified. G3P[8] strains clustered together in the same lineage with other novel human equine-like G3P[8] strains previously identified in multiple countries and presented a genotype 2 constellation (G3-P[8]-I2-R2-C2-M2-A2-N2-T2-E2-H2). Several amino acid differences were observed in the antigenic epitopes of the VP7 and VP8* capsid proteins of the equine-like G3P[8] compared with those of the RVA vaccine strains. The homology modeling of the VP7 and VP8* capsid proteins of the equine-like G3P[8] strains evidently exhibited that these residue differences were present on the surface-exposed area of the capsid structure. The emergence of the equine-like G3P[8] strains in Thailand indicates the rapid spread of strains with human and animal gene segments. Continuous surveillance for RVA is essential to monitor genotypes and genetic diversity, which will provide useful information for selecting rotavirus strains to develop a safe and effective RVA vaccine that is efficacious against multiple genotypes and variants.

• Korean Journal of Microbiology
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• v.23 no.1
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• pp.9-12
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• 1985

As a part of the host cell development for a amplified recombinant trp operon, $aroP^-$ mutation was introduced in a E. coli host strain. $aroP^-$ mutation was induced by transposon Tn10 and transduced into the E. coli host cell by bacteriophage P1Kc. The effect of $aroP^-$ mutation on the excretion of tryptophan in E. coli $trpR^{-ts}/ColE_1 -trp^+$ cells was investigated. Mutant lacking the general aromatic transport system was resistant to ${\beta}-2-thienylalanine\;(2{\times}10^{-4}\;M)$, p-fluorophenylalanine $(2{\times}10^{-4}M)$, or 5-methyltryptophan $(2{\times}10^{-4}\;M.)[^3H]-tryptophan$ uptake of the $aroP^-$ mutant strain was reduced considerably as compared with $aroP^+$ counterpart. The rate of $[^3H]-tryptophan$ uptake of the $aroP^-$ mutant strain treated with $NaN_3(3{\times}10^{-2}\;M)$ was much less affected than that of $aroP^+$ counterpart. The $aroP^-$ transductants increased the tryptophan excretion from E. coli $trpR^{-ts}/ColE_1 -trp^+$ four times more than $aroP^+$ counterpart.

• Journal of Microbiology and Biotechnology
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• v.17 no.9
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• pp.1538-1545
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• 2007

Clavulanic acid (CA) is an inhibitor of ${\beta}$-lactamase that is produced from Streptomyces clavuligerus NRRL3585 and is used in combination with other antibiotics in clinical treatments. In order to increase the production of CA, the replicative and integrative expressions of ccaR (encoding for a specific regulator of the CA biosynthetic operon) and cas2 (encoding for the rate-limiting enzyme in the CA biosynthetic pathway) were applied. Six recombinant plasmids were designed for this study. The pIBRHL1, pIBRHL3, and pIBRHL13 were constructed for overexpression, whereas pNQ3, pNQ2, and pNQ1 were constructed for chromosomal integration with ccaR, cas2, and ccaR-cas2, respectively. All of these plasmids were transformed into S. clavuligerus NRRL3585. CA production in transformants resulted in a significantly enhanced amount greater than that of the wild type, a 2.25-fold increase with pIBRHLl, a 9.28-fold increase with pNQ3, a 5.06-fold increase with pIBRHL3, a 2.93-fold increase with pNQ2 integration, a 5.79-fold increase with pIBRHLl3, and a 23.8-fold increase with pNQ1. The integrative pNQl strain has been successfully applied to enhance production.

• Biomedical Science Letters
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• v.13 no.3
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• pp.197-206
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• 2007

P2X receptors are membrane-bound ion channels that conduct $Na^+,\;K^+$, and $Ca^{2+}$ in response to ATP and its analogs. There are seven subunits identified so far ($P2X_1-P2X_7$). $P2X_2$ receptors are known to be expressed in a wide range of organs including brains and adrenal grands. PC12 cells are originated from adrenal grand and differentiated by nerve growth factor or pituitary adenylate cyclase activating poly peptide (PACAP). Previous studies indicate that $P2X_2$ receptor activation in PC12 cells couples to $Ca^{2+}-dependent$ release of catecholamine and ATP. It is known that acidic pH potentiates ATP currents at $P2X_2$ receptors. This leads to a hypothesis that $P2X_2$ receptors may play an important role in PC12 cell differentiation, one of the characteristics of which is neurite outgrowth, induced by the hormones under lower pH. In the present study, we isolated several clones which potentiate neurite outgrowth by PACAP in acidic pH (6.8), but not in alkaline pH (7.6). RT-PCR and electrophysiology data indicate that these clones express only functional $P2X_2$ receptors in the absence or presence of PACAP for 3 days. Potentiation of neurite outgrowth resulted from PACAP (100 nM) in acidic pH is inhibited by the two P2X receptor antagonists, suramin and PPADS ($100\;{\mu}M)$ each), and exogenous exprerssion of ATP-binding mutant $P2X_2$ receptor subunit ($P2X_2[K69A]$). However, acid sensing ion channels (ASICs) are not involved in PACAP-induced neurite outgrowth potentiation in lower pH since treatments of an inhibitor of ASICs, amyloride ($10\;{\mu}M$), did not give any effects to neurite extension. The vesicular proton pump ($H^+-ATPase$) inhibitor, bafilomycin (100 nM), reduced neurite extension indicating that ATP release resulted from $P2X_2$ receptor activation in PC12 cells is needed for neurite outgrowth. These were confirmed by activation of mitogen activated protein kinases, such as ERKs and p38. These results suggest roles of ATP and $P2X_2$ receptors in hormone-induced cell differentiation or neuronal synaptogenesis in local acidic environments.

• YAKHAK HOEJI
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• v.9 no.1_2
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• pp.1-3
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• 1965

A new compound, (5-nitro-2-furfurylidene)-p, $p^{'}$ -diaminodiphenylsulfone, was synthesized by refluxing the mixture of 5-nitrofurfural and p, $p^{'}$-diaminodiphenylsulfone$ in ethanol solution. It exhibited good antibactericidal action against several micro-organisms.

• Bulletin of the Korean Mathematical Society
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• v.58 no.4
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• pp.795-814
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• 2021

In this paper, we study the transcendental meromorphic solutions for the nonlinear differential equations: fⁿ + P(f) = R(z)e^α(z) and fⁿ + P_*(f) = p₁(z)e^α₁(z) + p₂(z)e^α₂(z) in the complex plane, where P(f) and P_*(f) are differential polynomials in f of degree n - 1 with coefficients being small functions and rational functions respectively, R is a non-vanishing small function of f, α is a nonconstant entire function, p₁, p₂ are non-vanishing rational functions, and α₁, α₂ are nonconstant polynomials. Particularly, we consider the solutions of the second equation when p₁, p₂ are nonzero constants, and deg α₁ = deg α₂ = 1. Our results are improvements and complements of Liao ([9]), and Rong-Xu ([11]), etc., which partially answer a question proposed by Li ([7]).

• Journal of Veterinary Clinics
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• v.23 no.1
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• pp.9-13
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• 2006

Anaplasma phagocytophilum major surface protein-2 (Msp2 or p44) is the immunodominant outer membrane protein of the bacterium. Recently, we disclosed that Msp2 was an A. phagocytophilum adhesin for binding to host neutrophils and HL-60 cells, probably mediated by attachment to platelet selectin glycoprotein ligand-1 (PSGL-1). In this study, we further elucidated that Msp2 bound to PSGL-1/FucT IV-transfected BJAB but not nontransfected BJAB cells. Binding of recombinant Msp2 or cell (lee bacteria to the surface of PSGL-1/FucT IV-transfected BJAB cells was significantly higher than to nontransfected BJAB cells (p<0.01 and p<0.01). Also, Msp2 monoclonal antibody and soluble recombinant Msp2 as antagonist led to concentration-dependent reductions in A. phagocytophilum adhesln (p<0.05 and p<0.01) to transfected BJAB cells. Thus, we conclude that Msp2 of. A. phagocytophilum acts as an adhesin by which the bacterium binds to PSGL-1 on host neutrophils and myeloid cells.