• Title/Summary/Keyword: KIT-6

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Effect of Iron Species in Mesoporous Fe-N/C Catalysts with Different Shapes on Activity Towards Oxygen Reduction Reaction

  • Kang, Taehong;Lee, Jiyeon;Kim, Jong Gyeong;Pak, Chanho
    • Journal of Electrochemical Science and Technology
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    • v.12 no.1
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    • pp.137-145
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    • 2021
  • Among the non-precious metal catalysts, iron-nitrogen doped carbon (Fe-N/C) catalysts have been recognized as the most promising candidates for an alternative to Pt-based catalysts for the oxygen reduction reaction (ORR) under alkaline and acidic conditions. In this study, the nano replication method using mesoporous silica, which features tunable primary particle sizes and shape, is employed to prepare the mesoporous Fe-N/C catalysts with different shapes. Platelet SBA-15, irregular KIT-6, and spherical silica particle (SSP) were selected as a template to generate three different kinds of shapes of the mesoporous Fe-N/C catalyst. Physicochemical properties of mesoporous Fe-N/C catalysts are characterized by using small-angle X-ray diffraction, nitrogen adsorption-desorption isotherms, and scanning electron microscopy images. According to the electrochemical evaluation, there is no morphological preference of mesoporous Fe-N/C catalysts toward the ORR activity with half-cell configuration under alkaline electrolyte. By implementing X-ray photoelectron spectroscopy analysis of Fe and N atoms in the mesoporous Fe-N/C catalysts, it is possible to verify that the activity towards ORR highly depends on the portions of "Fe-N" species in the catalysts regardless of the shape of catalysts. It was suggested that active site distribution in the Fe-N/C is one important factor towards ORR activity.

Potential immune-modulatory effects of wheat phytase on the performance of a mouse macrophage cell line, Raw 264.7, exposed to long-chain inorganic polyphosphate

  • An, Jeongmin;Cho, Jaiesoon
    • Animal Bioscience
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    • v.34 no.3_spc
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    • pp.463-470
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    • 2021
  • Objective: This experiment was conducted to find out the immunological effects of wheat phytase when long-chain inorganic polyphosphate (polyP) treated with wheat phytase was added to a macrophage cell line, Raw 264.7, when compared to intact long-chain polyP. Methods: Nitric oxide (NO) production of Raw 264.7 cells exposed to P700, a long-chain polyP with an average of 1,150 phosphate residues, treated with or without wheat phytase, was measured by Griess method. Phagocytosis assay of P700 treated with or without phytase in Raw 264.7 cells was investigated using neutral red uptake. The secretion of tumor necrosis factor α (TNF-α) by Raw 264.7 cells with wheat phytase-treated P700 compared to intact P700 was observed by using Mouse TNF-α enzyme-linked immunosorbent assay kit. Results: P700 treated with wheat phytase effectively increased NO production of Raw 264.7 cells by 172% when compared with intact P700 at 12 h exposure. At 5 mM of P700 concentration, wheat phytase promoted NO production of macrophages most strongly. P700, treated with wheat phytase, stimulated phagocytosis in macrophages at 12 h exposure by about 1.7-fold compared to intact P700. In addition, P700 treated with wheat phytase effectively increased in vitro phagocytic activity of Raw 264.7 cells at a concentration above 5 mM when compared to intact P700. P700 dephosphorylated by wheat phytase increased the release of TNF-α from Raw 264.7 cells by 143% over that from intact P700 after 6 h exposure. At the concentration of 50 μM P700, wheat phytase increased the secretion of cytokine, TNF-α, by 124% over that from intact P700. Conclusion: In animal husbandry, wheat phytase can mitigate the long-chain polyP causing damage by improving the immune capabilities of macrophages in the host. Thus, wheat phytase has potential as an immunological modulator and future feed additive for regulating immune responses caused by inflammation induced by long-chain polyP from bacterial infection.

Bacterial Community and Diversity from the Watermelon Cultivated Soils through Next Generation Sequencing Approach

  • Adhikari, Mahesh;Kim, Sang Woo;Kim, Hyun Seung;Kim, Ki Young;Park, Hyo Bin;Kim, Ki Jung;Lee, Youn Su
    • The Plant Pathology Journal
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    • v.37 no.6
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    • pp.521-532
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    • 2021
  • Knowledge and better understanding of functions of the microbial community are pivotal for crop management. This study was conducted to study bacterial structures including Acidovorax species community structures and diversity from the watermelon cultivated soils in different regions of South Korea. In this study, soil samples were collected from watermelon cultivation areas from various places of South Korea and microbiome analysis was performed to analyze bacterial communities including Acidovorax species community. Next generation sequencing (NGS) was performed by extracting genomic DNA from 92 soil samples from 8 different provinces using a fast genomic DNA extraction kit. NGS data analysis results revealed that, total, 39,367 operational taxonomic unit (OTU), were obtained. NGS data results revealed that, most dominant phylum in all the soil samples was Proteobacteria (37.3%). In addition, most abundant genus was Acidobacterium (1.8%) in all the samples. In order to analyze species diversity among the collected soil samples, OTUs, community diversity, and Shannon index were measured. Shannon (9.297) and inverse Simpson (0.996) were found to have the highest diversity scores in the greenhouse soil sample of Gyeonggi-do province (GG4). Results from NGS sequencing suggest that, most of the soil samples consists of similar trend of bacterial community and diversity. Environmental factors play a key role in shaping the bacterial community and diversity. In order to address this statement, further correlation analysis between soil physical and chemical parameters with dominant bacterial community will be carried out to observe their interactions.

Effects of Natural Mineral Water on Reflux Esophagitis (역류성 식도염에 대한 천연 미네랄 워터의 효과)

  • Choo, Byung-Kil
    • Korean Journal of Organic Agriculture
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    • v.30 no.1
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    • pp.75-87
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    • 2022
  • Reflux esophagitis (RE) is a gastroesophageal reflux disease (GERD) caused by repeated reflux of gastric acid into the esophagus. The present study investigated the protective effect of natural mineral water on esophageal injury induced by gastric acid reflux. The cytotoxicity of mineral water was confirmed using Cell viability, proliferation and cytotoxicity assay kit. The protective effect of mineral water on esophageal injury was investigated in RE rat model. The results showed that no cytotoxicity of mineral water was observed in RAW264.7 cells. Mineral water decreased the ratio of esophageal damage, inhibited the increase of inflammatory-protein expression levels and increased the mucosa protection and tight junction proteins expression level in RE control rat. The results suggest that mineral water may have the potential to protect esophageal damage caused by gastric acid reflux and the potential to alleviate reflux esophagitis.

Preliminary Study on Natural Killer Cell Activity for Interfer-on-Gamma Production after Gamma Knife Radiosurgery for Brain Tumors

  • Park, Kawngwoo;Jeong, Sang Soon;Kim, Jung Hoon;Chung, Hyun-Tai;Lee, Eun Jung;Moon, Hyo Eun;Park, Kwang Hyon;Kim, Jin Wook;Park, Hye Ran;Lee, Jae Meen;Lee, Hye Ja;Kim, Hye Rim;Cho, Yong Hwan;Paek, Sun Ha
    • Journal of Korean Neurosurgical Society
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    • v.65 no.6
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    • pp.861-867
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    • 2022
  • Objective : High-dose radiation is well known to induce and modulate the immune system. This study was performed to evaluate the correlation between clinical outcomes and changes in natural killer cell activity (NKA) after Gamma Knife Radiosurgery (GKS) in patients with brain cancer. Methods : We performed an open-label, prospective, cross-sectional study of 38 patients who were treated with GKS for brain tumors, including metastatic and benign brain tumors. All of the patients underwent GKS, and blood samples were collected before and after GKS. NKA was measured using an enzyme-linked immunosorbent assay kit, to measure interferon-gamma (IFNγ) secreted by ex vivo-stimulated NK cells from whole blood. We explored the correlations between NK cell-produced IFNγ (NKA-IFNγ) levels and clinical parameters of patients who were treated with GKS for brain tumors. Results : NKA-IFNγ levels were decreased in metastatic brain tumor patients compared to those with benign brain tumors (p<0.0001). All the patients who used steroid treatment to reduce brain swelling after GKS had an NKA-IFNγ level of zero except one patient. High NKA-IFNγ levels were not associated with a rapid decrease in brain metastasis and did not increase after GKS. Conclusion : The activity of NK cells in metastatic brain tumors decreased more than that in benign brain tumors after GKS.

Effect of Low-level Laser Therapy on Propylthiouracil-induced Hypothyroidism Model Mice: A Pilot Study

  • Mun, In Kwon;Yoo, Won Sang;Lee, Sang Joon;Chung, Phil-Sang;Woo, Seung Hoon
    • Medical Lasers
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    • v.10 no.1
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    • pp.37-44
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    • 2021
  • Background and Objectives Hypothyroidism is the most common endocrine disease. On the other hand, there is no treatment that can improve the thyroid function. Low-level laser therapy (LLLT) can improve the cellular activity. The effect of hypothyroidism is not obvious. This study examined the effects of LLLT on the thyroid gland function of a propylthiouracil (PTU)-induced hypothyroidism mouse model. Materials and Methods Twenty-five male ICR mice were distributed into five groups of five animals each: Negative control (none PTU animal) and positive control (PTU animal) of unirradiated animals, and three experimental groups with LLLT (3J, 6J, and 12J). Each mouse was exposed to a distinct dose of a 632-nm laser once a week for three rounds. The positive control group and three LLLT groups were induced into a hypothyroidism state by PTU administration. The animals' thyroid-stimulating hormone and thyroxine levels were measured using an ELISA kit, and their thyroid tissue was harvested and analyzed after sacrifice at the end of the experiment. The hormone level and morphological changes in the tissue of the five groups were compared. Results The thyroid hormone levels in the control group and LLLT groups were similar. On the other hand, the thyroid tissue of the LLLT groups showed some morphological changes that were similar to those of iodine deficiency thyroid. Conclusion LLLT did not affect the thyroid gland function in PTU-induced hypothyroidism mice.

Residue Characteristics and Risk Assessment of Pesticides (Boscalid and Pyraclostrobin) in Hylomecon vernalis (피나물 중 boscalid 및 pyraclostrobin의 토양 처리시 잔류특성 및 안전성 평가)

  • Yu, Ji-Woo;Song, Min-Ho;Kim, Jinchan;Lee, Kwanghun;Ko, Rakdo;Keum, Young-Soo;Lee, Jiho
    • Korean Journal of Environmental Agriculture
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    • v.41 no.2
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    • pp.95-100
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    • 2022
  • BACKGROUND: This study was aimed to determine characteristics of residues of the soil-treated boscalid and pyraclostrobin within Hylomecon vernalis and to evaluate the risks from intake of the residual pesticides in the crop. METHODS AND RESULTS: The pesticides were treated to soils at two different concentrations, and the plant samples were collected 57 days after seeding. The samples were extracted using the QuEChERS extraction kit (MgSO4 4 g, NaCl 1 g). The quantitative methods for boscalid and pyraclostrobin were validated using linearity, recovery, and CV (coefficient of variation). Risk assessment of the pesticides was performed using Korea national nutrition statistics 2019. CONCLUSION(S): The residual levels of boscalid were 0.02-0.05 mg/kg (for the treatment at 6 Kg/10a) and 0.05-0.08 mg/kg (for the treatment at 12 Kg/10a), respectively. The residual concentrations of pyraclostrobin were below the LOQ. The amounts of pesticides were less than Maximum Residue Limits specified by the Korean Ministry of Food and Drug Safety. The maximum hazard indices of boscalid in chwinamul and amaranth for consumers were 0.0075% and 0.1525%, respectively, and it indicates that the risk of the pesticides from the crop is considered to be low.

Prevalence of giardiasis of stray cats in the Daejeon city

  • Dong-Kwan, Lee;Han-Joon, Lee;Joong-Hyun, Song;Kun-Ho, Song
    • Korean Journal of Veterinary Service
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    • v.45 no.4
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    • pp.249-252
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    • 2022
  • Giardiasis is widespread all over the world, and it is a disease that causes both acute and chronic digestive symptoms. It is zoonotic disease that affects animals and humans. There are few studies on giardiasis in stray cats due to difficulties in catching and sampling. Therefore, this study evaluated the prevalence of giardiasis in stray cats in the Daejeon city because of increasing interest as zoonotic disease. The specimens were the feces of stray cats captured for the neutering project (TNR) in Daejeon; 30 fecal samples were collected from 2021 to 2022 in each of 5 districts in Daejeon. A total of 150 samples were collected. All samples were tested for giardiasis using the Giardia SNAP kit (SNAP test, IDEXX Laboratories. Inc., Westbrook, ME). The overall prevalence rate was 46 out of 150 cats (30.7%). By age, 25 out of 71 juvenile cats (35.2%) were positive, and 21 out of 79 adult cats (26.6%) were positive. A total of 19 out of 69 cats (27.5%) with diarrhea were positive, and 27 out of 81 asymptomatic cats (33.3%) were positive. For gender, 38 out of 99 females (38.4%) were positive, and 8 out of 51 males (15.7%) were positive. The positive rate of giardiasis in stray cats was over 30%, which is high compared to other research results. It is necessary to increase the public's awareness of the value of deworming stray cats and the sanitation of people who have come into contact with them.

Anti-inflammatory Effect of Bodusan (보두산(寶豆散) 메탄올 추출물의 항염증 효과)

  • Kim, Pan-Joon;Yun, Hyun-Jeong;Heo, Sook-Kyoung;Kim, Kyoung-Ae;Kim, Dong-Wan;Kim, Jae-Eun;Park, Sun-Dong
    • The Korea Journal of Herbology
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    • v.24 no.2
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    • pp.49-56
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    • 2009
  • Objectives : Inflammation is important event in the development of vascular diseases including hypertension, atherosclerosis, and restenosis. Bodusan (BDS) was a traditional Korean herbal medicine and widely used in treatment of gastrointestinal complaint and stomach ulcer. The aim of this study was to determine whether BDS and its components inhibit production of nitrite, PGE2 and proinflammatory cytokines in lipopolysaccharide (LPS)-treated RAW 264.7 macrophages. Methods : Cytotoxic activity of BDS and its components on RAW 264.7 cells was using 5-(3caroboxymcrophages. eth-oxyphenyj)-2H-tetra-zolium inner salt (MTS) assay. The nitric oxide (NO) production was measured by Griess reagent system. And proinflammatory cytokines were measured by ELISA kit. The levels of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expression were detected by western blot. Results : Our results indicated that BDS and its components significantly inhibited the LPS-induced NO and PGE2 production. Moreover. BDS and its components inhibited iNOS and COX-2 expression accompanied by an attenuation of TNF-${\alpha}$, IL-11${\beta}$, IL-6 and MCP-1 formation in macrophages. Conclusions: These results indicate that BDS and its components have potential as an anti-inflammatory agent.

Local and regional steppe vegetation palatability at grazing hotspot areas in Mongolia

  • Amartuvshin, Narantsetsegiin;Kim, Jaebeom;Cho, Nanghyun;Seo, Bumsuk;Kang, Sinkyu
    • Journal of Ecology and Environment
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    • v.46 no.1
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    • pp.76-84
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    • 2022
  • Background: Climate and livestock grazing are key agents in determining current Mongolian steppe vegetation communities. Together with plant coverage or biomass, palatability of steppe community is regarded as a useful indicator of grassland degradation, in particular, at grazing hotspots in arid and semi-arid grasslands. This study analyzed relationships between livestock grazing pressure and steppe vegetation palatability at three summer pastures with different aridity (dry, xeric, and mesic) and livestock numbers (1,100, 1,800, and 4,100 sheep units, respectively). At each site, it was surveyed coverage, biomass, and species composition of different palatability groups (i.e., palatable [P], impalatable [IP], and trampling-tolerant [TT]) along a 1-km transect from grazing hotspots (i.e., well) in every July from 2015 to 2018. Results: In results, total vegetation coverage increased with wetness, 7 times greater at mesic site than dry one in averages (33.1% vs. 4.5%); biomass was 3 times higher (47.1 g m-2 vs. 15.7 g m-2). Though P was the dominant palatability group, the importance of IP in total coverage increased with aridity from mesic (0.6%) to dry (40.2%) sites. Whereas, TT increased with livestock numbers across sites. Locally, IP was observed more frequently near the wells and its spatial range of occurrence becomes farther along the transects with aridity across sites from mesic (< 100 m) to dry (< 700 m from the well). Conclusions: Our results showed that the importance of IP and its spatial distribution are different at both local and regional scales, indicating that the palatability parameters are sensitive to discern balance between selective-grazing demand and climate-driven foraging supply in Mongolian rangelands.