• Food Science and Biotechnology
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• v.14 no.1
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• pp.73-76
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• 2005

The acaricidal activities of 12 commercial constituents derived from Eugenia caryophyllata leaf oils against Dermatophagoides farinae, D. pteronyssinus and Tyrophagus putrescentiae adults were examined using an impregnated fabric disk application and compared with that of the commercial benzyl benzoate as synthetic acaricide. On the basis of $LD_{50}$ values, the most toxic compound was methyl eugenol ($4.13\;{\mu}g/cm^2$), followed by methyl isoeugenol ($4.19\;{\mu}g/cm^2$), isoeugenol ($4.29\;{\mu}g/cm^2$), eugenol ($4.94\;{\mu}g/cm^2$), and acetyl eugenol ($13.91\;{\mu}g/cm^2$) against D. farinae. In the case of D. pteronyssinus, isoeugenol ($2.93\;{\mu}g/cm^2$) was the most toxic, followed by methyl isoeugenol ($3.28\;{\mu}g/cm^2$), methyl eugenol ($3.87\;{\mu}g/cm^2$), eugenol ($3.92\;{\mu}g/cm^2$), and acetyl eugenol ($7.21\;{\mu}g/cm^2$). These results suggest that D. pteronyssinus may be controlled more effectively by the application of eugenol congeners than D. farinae. In comparison with synthetic acaricides, the acaricidal activities of eugenol, isoeugenol, methyl eugenol, and methyl isoeugenol were about 1.9-2.2 times more toxic than benzyl benzoate. Furthermore, the most toxic constituent against T. putrescentiae was exhibited on eugenol ($10.11\;{\mu}g/cm^2$), followed by methyl eugenol ($38.67\;{\mu}g/cm^2$) and acetyl eugenol ($70.09\;{\mu}g/cm^2$), but no activity was observed for isoeugenol and methyl isoeugenol. The results suggested that eugenol congeners may be useful as a new source for selective control of house dust mites and stored food mites.

• Fire Science and Engineering
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• v.30 no.5
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• pp.108-115
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• 2016

Fire detectors play an important role in alerting the related people to the initial stages of fire to protect assets and life. Therefore, the performance in detecting fires in the early stages without the risk of false alarms is important. Owing to a recent revision of the national fire safety standards to install smoke detectors in living rooms used for sleeping, staying, hospitalizing in apartment house/efficiency apartment/lodging facility/medical facility/facility for elderly and young, the application of smoke detectors is increasing. On the other hand, there is lack of research in preventing false alarms. This study improved algorithms to prevent false alarms in analog photoelectric smoke detector's due to sudden dust and better classify pollution and fire signals through a self-compensatory function. Through this study, alternatives are suggested to reduce the number of false alarms of Analog Photoelectric smoke detectors, and prevent financial losses due to false alarms.

• The Korean Journal of Physiology and Pharmacology
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• v.19 no.3
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• pp.291-297
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• 2015

An oral environment is constantly exposed to environmental factors and microorganisms. The periodontal ligament (PDL) fibroblasts within this environment are subject to bacterial infection and allergic reaction. However, how these condition affect PDL fibroblasts has yet to be elucidated. PDL fibroblasts were isolated from healthy donors. We examined using reverse transcription-polymerase chain reaction and measuring the intracellular $Ca^{2+}$ concentration ($[Ca^{2+}]_i$). This study investigated the receptors activated by exogenous bacterial pathogens (Lipopolysaccharide and peptidoglycan) and allergens (German cockroach extract and house dust mite) as well as these pathogenic mediators-induced effects on the intracellular $Ca^{2+}$ signaling in human PDL fibroblasts. Moreover, we evaluated the expression of pro-inflammatory cytokines (interleukin (IL)-$1{\beta}$, IL-6, and IL-8) and bone remodeling mediators (receptor activator of NF-${\kappa}B$ ligand and osteoprotegerin) and intracellular $Ca^{2+}$-involved effect. Bacterial pathogens and allergic mediators induced increased expression of pro-inflammatory cytokines, and these results are dependent on intracellular $Ca^{2+}$. However, bacterial pathogens and allergic mediators did not lead to increased expression of bone remodeling mediators, except lipopolysaccharide-induced effect on receptor activator of NF-${\kappa}B$ ligand expression. These experiments provide evidence that a pathogens and allergens-induced increase in $[Ca^{2+}]_i$ affects the inflammatory response in human PDL fibroblasts.

• Journal of the Korean Society of Safety
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• v.33 no.4
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• pp.1-7
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• 2018

This paper is analyzed for the thermal characteristics(1 year) of the 6 components(DC breaker, DC filter(including capacitor and discharge resistance), IGBT(Insulated gate bipolar mode transistor), AC filter, AC breaker, etc.) of a photovoltaic power generation-based PCS(Power conditioning system) below 20 kW. Among the modules, the discharge resistance included in the DC filter indicated the highest heat at $125^{\circ}C$, and such heat resulting from the discharge resistance had an influence on the IGBT installed on the rear side the board. Therefore, risk priority through risk priority number(RPN) of FMEA(Failure modes and effects analysis) sheet is conducted for classification into top 10 %. According to thermal characteristics and FMEA, it is necessary to pay attention to not only the in-house defects found in the IGBT, but also the conductive heat caused by the discharge resistance. Since it is possible that animal, dust and others can be accumulated within the PCS, it is possible that the heat resulting from the discharge resistance may cause fire. Accordingly, there are two options that can be used: installing a heat sink while designing the discharge resistance, and designing the discharge resistance in a structure capable of avoiding heat conduction through setting a separation distance between discharge resistance and IGBT. This data can be used as the data for conducting a comparative analysis of abnormal signals in the process of developing a safety device for solar electricity-based photovoltaic power generation systems, as the data for examining the fire accidents caused by each module, and as the field data for setting component management priorities.

• Allergy, Asthma & Immunology Research
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• v.10 no.6
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• pp.686-697
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• 2018

Purpose: Several markers for eosinophilic inflammation have been proposed to predict response to asthma treatment. However, definitive criteria for treatment decisions have not yet been established. We investigate a potentially useful relatively non-invasive biomarker, eosinophil-derived neurotoxin (EDN), to predict favorable responses to budesonide or montelukast, common treatment for children with asthma. Methods: Young children (1 to 6 years old) were enrolled in this randomized, parallel, 2-group, open-label trial. Criteria for eligibility included: 1) being symptomatic during the run-in period; and 2) having a serum EDN (sEDN) level ${\geq}53ng/mL$, with positive specific immunoglobulin E to house dust mite. Eligible patients were randomly placed into 2 groups: the BIS group received budesonide inhalation suspension (BIS) 0.5 mg once daily; the MONT group received montelukast 4 mg once daily. Ineligible patients were invited to receive montelukast 4 mg once daily (OBS group). Treatment period was 12 weeks. Results: Asthma control days increased significantly in the BIS and MONT groups (P < 0.000) over the 12-week study period. There was no significant change in sEDN in the BIS group but there was a significant decrease in the MONT group (P < 0.000). Patients in the OBS group with high EDN levels (> 53 ng/mL) showed a significant decrease due to MONT treatment (P = 0.023). Rescue medication usage significantly decreased in the BIS and MONT groups (P < 0.000). Conclusions: EDN is a useful relatively non-invasive biomarker for predicting responses to montelukast and budesonide treatment of preschool children with beta2-agonist responsive recurrent wheeze and multiple-trigger wheeze (Trial registry at UMIN Clinical Trials Registry, UMIN000008335).

• Molecules and Cells
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• v.44 no.8
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• pp.580-590
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• 2021

Patients with severe asthma have unmet clinical needs for effective and safe therapies. One possibility may be mesenchymal stem cell (MSC) therapy, which can improve asthma in murine models. However, it remains unclear how MSCs exert their beneficial effects in asthma. Here, we examined the effect of human umbilical cord blood-derived MSCs (hUC-MSC) on two mouse models of severe asthma, namely, Alternaria alternata-induced and house dust mite (HDM)/diesel exhaust particle (DEP)-induced asthma. hUC-MSC treatment attenuated lung type 2 (Th2 and type 2 innate lymphoid cell) inflammation in both models. However, these effects were only observed with particular treatment routes and timings. In vitro co-culture showed that hUC-MSC directly downregulated the interleukin (IL)-5 and IL-13 production of differentiated mouse Th2 cells and peripheral blood mononuclear cells from asthma patients. Thus, these results showed that hUC-MSC treatment can ameliorate asthma by suppressing the asthmogenic cytokine production of effector cells. However, the successful clinical application of MSCs in the future is likely to require careful optimization of the route, dosage, and timing.

• Parasites, Hosts and Diseases
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• v.61 no.2
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• pp.202-209
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• 2023

Lophomonas blattarum is an anaerobic protozoan living in the intestine of cockroaches and house dust mites, with ultramicroscopic characteristics such as the presence of a parabasal body, axial filament, and absence of mitochondria. More than 200 cases of Lophomonas infection of the respiratory tract have been reported worldwide. However, the current diagnosis of such infection depends only on light microscopic morphological findings from respiratory secretions. In this study, we attempted to provide more robust evidence of protozoal infection in an immunocompromised patient with atypical pneumonia, positive for Lophomonas-like protozoal cell forms. A direct search of bronchoalveolar lavage fluid via polymerase chain reaction (PCR), transmission electron microscopy (TEM), and metagenomic next-generation sequencing did not prove the presence of protozoal infection. PCR results were not validated with sufficient rigor, while de novo assembly and taxonomic classification results did not confirm the presence of an unidentified pathogen. The TEM results implied that such protozoal forms in light microscopy are actually non-detached ciliated epithelial cells. After ruling out infectious causes, the patient's final diagnosis was drug-induced pneumonitis. These findings underscore the lack of validation in the previously utilized diagnostic methods, and more evidence in the presence of L. blattarum is required to further prove its pathogenicity.

• Korean Journal of Clinical Laboratory Science
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• v.49 no.2
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• pp.128-134
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• 2017

Der p 1 and Der p 2 are essential allergens of house dust mite associated with the development of asthma. In the present study, we examined whether Der p 1 and Der p 2 induce a release of S100A8 and S100A9 in monocytes, which are involved in the regulatory mechanism of neutrophil apoptosis. We found that Der p 1 and Der p 2 significantly increased the secretion of S100A8 and S100A9 in normal monocytes. Moreover, S100A8 and S100A9 strongly suppressed the spontaneous apoptosis of normal and asthmatic neutrophils. The inhibitory effect of S100A9 was stronger than that of S100A8, and asthmatic neutrophils showed a higher inhibitory effect than normal neutrophils. S100A8 and S100A9 induced activation of Lyn, Akt, and ERK in a time-dependent manner. These findings elucidate the roles of Der p 1 and Der p 2 in the interaction between monocytes and neutrophils, as well as contributing to our knowledge of the pathogenesis of allergic diseases.

• Korean Journal of Clinical Laboratory Science
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• v.47 no.4
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• pp.230-236
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• 2015

Dermatophagoides pteronissinus (DP) is one of the house dust mites (HDM) associated with allergic diseases. The cysteine protease Der p 1 from DP is a powerful allergen. The pathogenic mechanism of allergy is involved in cytokine secretion of lymphocytes and spontaneous apoptosis of neutrophils. In this study, we investigated whether Der p 1 induces cytokine secretion of lymphocytes and if the release of cytokines is associated with regulation of neutrophil apoptosis. In normal and allergic subjects, Der p 1 increased IL-6, IL-8, MCP-1, and GM-CSF release in a time-dependent course. Supernatants collected from normal and allergic neutrophils after Der p 1 stimulation suppressed the apoptosis of normal and allergic neutrophils, although Der p 1 alone has no effect on neutrophils. Der p 1 suppressed neutrophil apoptosis in coculture of normal neutrophils with normal lymphocytes. Der p 1 more strongly suppressed apoptosis of allergic neutrophils cocultured with allergic lymphocytes than normal neutrophils cocultured with normal lymphocytes. In summary, Der p 1 increases the secretion of cytokines, which has anti-apoptotic effects on neutrophils of normal and allergic subjects. These results will contribute to elucidate the pathogenic mechanism of allergic diseases.

• Journal of Mushroom
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• v.14 no.4
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• pp.155-161
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• 2016

A recent study reported that Pleurotus ostreatus has the potential to be used as a ${\beta}-glucan-based$ cream for supportive complementary therapy of atopic dermatitis. KH054 is a new herbal prescription consisting of P. ostreatus and Panax ginseng. The effects of atopic dermatitis-induced materials on the expression of cytokine genes in human monocytes (THP-1, EoL- 1) have been examined. Some reports demonstrated that P. ginseng augments the activity of natural killer cells, which plays an important role in innate immunity against infection and tumor development. Monocyte chemotactic protein 1 (MCP-1), interleukin (IL)-6, and IL-8 have important roles in mediating the infiltration of various cells into the skin of atopic dermatitis and psoriasis. The present study investigated whether KH054 on induced IL-6, IL-8, and MCP-1 secretion by house dust mite (Dermatophagoides pteronissinus) in THP-1 (human acute monocytic leukemia) and EoL-1(Human eosinophilic leukemia) cell. D. pteronissinus functions in the pathogenesis of allergic diseases, including atopic dermatitis and asthma. The inhibitory effect of KH054 on the induction of IL-6, IL-8, and MCP-1 secretion by D. pteronissinus extract in THP-1 and EoL-1 cells was examined. KH054 potently suppressed the elevated production of IL-6 and IL-8 induced by D. pteronissinus treatment in THP-1 and EoL-1 cells. Based on the present results, KH054 may be useful for developing functional foods to treat atopic dermatitis.