• Journal of Microbiology and Biotechnology
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• 제20권3호
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• pp.485-493
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• 2010

A modified graphite felt electrode with neutral red (NR-electrode) was shown to catalyze the chemical oxidation of nitrite to nitrate under aerobic conditions. The electrochemically oxidized NR-electrode (EO-NR-electrode) and reduced NR-electrode (ER-NR-electrode) catalyzed the oxidation of $1,094{\pm}39$ mg/l and $382{\pm}45$ mg/l of nitrite, respectively, for 24 h. The electrically uncharged NR-electrode (EU-NR-electrode) catalyzed the oxidation of $345{\pm}47$ mg/l of nitrite for 24 h. The aerobic bacterial community immobilized in the EO-NR-electrode did not oxidize ammonium to nitrite; however, the aerobic bacterial community immobilized in the ER-NR-electrode bioelectrochemically oxidized $1,412{\pm}39$ mg/l of ammonium for 48 h. Meanwhile, the aerobic bacterial community immobilized on the EU-NR-electrode biochemically oxidized $449{\pm}22$ mg/l of ammonium for 48 h. In the continuous culture system, the aerobic bacterial community immobilized on the ER-NR-electrode bioelectrochemically oxidized a minimal $1,337{\pm}38$ mg/l to a maximal $1,480{\pm}38$ mg/l of ammonium to nitrate, and the community immobilized on the EU-NR-electrode biochemically oxidized a minimal $327{\pm}23$ mg/l to a maximal $412{\pm}26$ mg/l of ammonium to nitrate every two days. The bacterial communities cultivated in the ER-NR-electrode and EU-NR-electrode in the continuous culture system were analyzed by TGGE on the $20^{th}$ and $50^{th}$ days of incubation. Some ammonium-oxidizing bacteria were enriched on the ER-NR-electrode, but not on the EU-NR-electrode.

• 한국대기환경학회지
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• 제33권2호
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• pp.124-138
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• 2017

Physico-chemical measurement of non-refractory submicron particles($NR-PM_1$) was conducted in Baengnyeong Island, Korea using Aerodyne High Resolution Time of Flight Aerosol Mass Spectrometer (HR-ToF-AMS) from 2012 to 2014. Organics and ammoniated sulfate were dominant species in $NR-PM_1$. The organics was found to have similar fractions(approximate 40%) of $NR-PM_1$ during the summer and winter, while the sulfate fractions of $NR-PM_1$ were calculated to be approximately 47% and 31% for the summer and winter, respectively, suggesting the possibility that particles provide non-acidic surfaces for condensation of nitric acid in the winter. The nitrate fractions of approximate 4% and 20% of $NR-PM_1$ were observed in August (summer) and November (winter), respectively, resulting that the relatively low concentration of sulfate in $NR-PM_1$ provided a non-acidic surface for nitric acid condensation and formation of particulate ammoniated nitrate is favored thermodynamically in winter. The new particle formation (NPF) event and particle growth rate were analyzed for each month in 2014 using Scanning Mobility Particle Sizer(SMPS). The Percent of NPF events was the highest in winter, but NPF event was not observed during summer due to relatively high temperature and frequent rainfall. The average particle growth rate was 3.5 nm/h and the highest particle growth rate was 5.5 nm/h in May. We observed the long-range transport of the anthropogenic sulfate from the East Asia during the intensive monitoring period of November between Qingdao and Baengnyeong Island in 2013. The relatively high concentrations of m/z 60 measured in HR-ToF-AMS was observed in May and June at Baengnyeong Island, suggesting the possibility of the influence of biomass burning from the East Asia to the Korean Peninsula.

• Applied Microscopy
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• 제40권2호
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• pp.53-64
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• 2010

글루타메이트 수용체는 신경연접의 발달에서 신경연접과 정제 등에 중요한 역할을 한다. 포유류 청각뇌줄기의 가쪽위올리브 핵-안쪽마름섬유체핵 신경연접에서의 흥분성 신경전달물질의 전달은 글루타메이트와 같은 많은 흥분성 신경전달물질의 전달을 조절하므로 발생학적 연구에 매우 유용한 모델이다. 귀먹음은 흥분성 회로 또는 억제성 회로의 신경연접에서 신경전달물질들의 변화뿐 아니라 형태학적 변화도 초래하게 된다. 이런 이유로 선천적으로 태어나면서 달팽이 기관이 퇴화되는 선회생쥐는 귀먹음의 병태생리를 연구하는데 가장 좋은 동물모델이다. 그러나, 선회생쥐에서 이런 NMDA 수용체 각각의 아형들이 발달에 따라 어떻게 나타나는지에 관해서는 거의 알려진 사실이 없다. 따라서, 본 연구에서는 선천적으로 속귀에 돌연변이를 가진 선회생쥐를 이용하여 면역조직화학염색법으로 생후 7일과 16일의 쥐를 정상쥐와 비교해서 글루타메이트성의 흥분성 신호가 전달되는 청각뇌줄기의 가쪽위올리브핵(LSO)에서 N-메틸-D-아스파르 트산염(NMDA) 수용체의 아형인 NR1, NR2A, NR2B의 분포를 각각 조사하였다. 생후 7일째 선회생쥐의 NR1에 대한 면역반응성의 세기는 정상군에서 $128.67\pm8.87$로 나타났고 이형접합체에서는 $111.06\pm8.04$, 동형접합체에서는 $108.09\pm5.94$으로 나타났다. 그리고 생후 16일째 선회생쥐에서는 정상군에서 $43.83\pm10.49$, 이형접합체에서는 $40\pm13.88$, 동형접합체에서는 $55.96\pm17.35$으로 나타났다. 생후 7일째 선회생쥐의 NR2A에 대한 면역반응성의 세기는 정상군에서 $97.97\pm9.71$, 이형접합체에서 $102.87\pm9.30$, 동형접합체에서 $106.85\pm5.79$로 나타났다. 생후 16일 선회생쥐의 가쪽위올리브핵에서의 NR2A에 대한 면역반응성 세기는 정상군에서 $47.4\pm20.6$, 이형접합체에서 $43.9\pm17.5$, 동형접합체에서 $49.2\pm20.1$로 나타났다. 생후 7일의 선회생쥐의 NR2B의 면역반응성 세기는 정상군에서 $109.04\pm6.77$, 이형접합체에서 $106.43\pm10.24$, 동형접합체에서 $105.98\pm4.10$으로 나타났다. 생후 16일째 선회생쥐의 NR2B의 면역반응성의 세기는 정상군에서 $101.47\pm11.50$, 이형접합체에서 $91.47\pm14.81$, 동형접합체에서 $93.93\pm15.71$으로 나타났다. 이 결과들은 생후 7일과 16일의 선회생쥐의 가쪽위올리브핵에서 NMDA 수용체의 면역반응성의 변화를 나타낸 것으로 인간 귀먹음의 주요한 병태생리를 파악하는 데 기본적인 자료를 제시할 수 있을 것이다.

• 한국수산과학회지
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• 제44권1호
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• pp.64-70
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• 2011

Nitrate reductase (NR) is activated by nitrogen sources (${NO_3}^-$ and ${NH_4}^+$) and irradiance. This study investigated the effects of these factors on the NR activity of Ulva pertusa (Chlorophyta) and Ecklonia cava (Phaeophyta). In addition, the ammonium (${NH_4}^+$) and nitrate (${NO_3}^-$) uptake rates of the two species were examined. U. pertusa took up most of the ${NO_3}^-$ and ${NH_4}^+$ in the medium during a 3hour incubation, while E. cava had a relatively high uptake rate after 3 hours. The NR activities of the two species were affected by the nitrogen source and irradiance and were highest when they were exposed to ${NO_3}^-$-rich medium and high irradiance. However, the patterns of NR activity differed between the two species. In ${NO_3}^-$-rich medium and high irradiance, U. pertusa achieved the highest NR activity ($2.01{\pm}0.07\;{\mu}mol$ ${NO_2}^-$ $g^{-1}$ DW $h^{-1}$) within the first 3 hours and then this activity decreased drastically. By contrast, the NR activity of E. cava ($0.36{\pm}0.04\;{\mu}mol$ ${NO_2}^-$ $g^{-1}$ DW $h^{-1}$) was constant for 12 hours. When exposed to darkness, the NR activity of U. pertusa decreased dramatically, while that of E. cava increased gradually for 12 hours. Therefore, E. cava is able to maintain NR activity during the dark because of its adequate carbohydrate reserves and substrate.

• 대한화학회지
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• 제55권5호
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• pp.746-750
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• 2011

Fluorescence correlation spectroscopy (FCS) is an emerging fluorescence technique used to study the dynamics of proteins on a millisecond to microsecond time scale at the single-molecule level. Solution pH-modulated protein conformational changes can be manifested by binding rate, fluorescence lifetime, and binding specificity of a probe molecule. The fluorescence lifetime of Nile red (NR) bound to apomyoglobin (apoMb) was measured to be $6{\pm}0.3$ ns, much longer than that in water solution ($2.9{\pm}0.2$ ns). As the unfolding population of apoMb increased by lowering pH of solution, the fraction for the longer lifetime of NR decreased with an increasing fraction for the shorter lifetime of NR in water. Unlike 1-anilino-8-naphthalene sulfonic acid, which has many lifetimes due to nonspecific binding to the unfolded apoMb, NR bound to apoMb possesses only a single lifetime. These results suggest that NR binds specifically to native apoMb and thus can be utilized to probe the folding/unfolding dynamics of apoMb using FCS.

• The Korean Journal of Physiology and Pharmacology
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• 제13권3호
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• pp.209-214
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• 2009

The striatum receives glutamatergic afferents from the cortex and thalamus, and these synaptic transmissions are mediated by ${\alpha}$-amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA) and N-methyl D-aspartate (NMDA) receptors. The purpose of this study was to characterize glutamate receptors by analyzing NMDA/AMPA ratio and rectification of AMPA and NMDA excitatory postsynaptic currents (EPSCs) using a whole-cell voltage-clamp method in the dorsal striatum. Receptor antagonists were used to isolate receptor or subunit specific EPSC, such as (DL)-2-amino-5-phosphonovaleric acid (APV), an NMDA receptor antagonist, ifenprodil, an NR2B antagonist, CNQX, an AMPA receptor antagonist and IEM-1460, a GluR2-lacking AMPA receptor blocker. AMPA and NMDA EPSCs were recorded at - 70 and + 40 mV, respectively. Rectification index was calculated by current ratio of EPSCs between + 50 and - 50 mV. NMDA/AMPA ratio was 0.20${\pm}$0.05, AMPA receptor ratio of GluR2-lacking/GluR2-containing subunit was 0.26${\pm}$0.05 and NMDA receptor ratio of NR2B/NR2A subunit was 0.32${\pm}$0.03. The rectification index (control 2.39${\pm}$0.27) was decreased in the presence of both APV and combination of APV and IEM-1460 (1.02${\pm}$0.11 and 0.93${\pm}$0.09, respectively). These results suggest that the major components of the striatal glutamate receptors are GluR2-containing AMPA receptors and NR2A-containing NMDA receptors. Our results may provide useful information for corticostriatal synaptic transmission and plasticity studies.

• BMB Reports
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• 제41권3호
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• pp.242-247
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• 2008

MSS, a comprising mixture of maesil (Prunus mume Sieb. et Zucc) concentrate, disodium succinate and Span80 (3.6 : 4.6 : 1 ratio) showed a significant improvement of memory when daily administered (460 mg/kg day, p.o.) into the normal rats for 3 weeks. During the spatial learning of 4 days in Morris water maze test, both working memory and short-term working memory index were significantly increased when compared to untreated controls. We investigated a molecular signal transduction mechanism of MSS on the behaviors of spatial learning and memory. MSS treatment increased hippocampal mRNA levels of NR2B and TrkB without changes of NR1, NR2A, ERK1, ERK2 and CREB. However, the protein levels of pERK/ERK and pCREB/CREB were all significantly increased to $1.5{\pm}0.17$ times. These results suggest that the improving effect of spatial memory for MSS is linked to MAPK/ERK signaling pathway that ends up in the phosphorylation of CREB through TrkB and/or NR2B of NMDA receptor.

• 한국대기환경학회지
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• 제34권3호
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• pp.430-446
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• 2018

To improve understanding of the sources and chemical properties of particulate pollutants on the Korean Peninsula, An Aerodyne High Resolution Time of Flight Aerosol Mass Spectrometer (HR-ToF-AMS) measured non-refractory fine particle ($NR-PM_1$) from 2013 to 2015 at Baengnyeong Island and Seoul metropolitan area (SMA), Korea. The chemical composition of $NR-PM_1$ in Baengnyeong island was dominated by organics and sulfate in the range of 36~38% for 3 years, and the organics were the dominant species in the range of 44~55% of $NR-PM_1$ in Seoul metropolitan area. The sulfate was found to be more than 85% of the anthropogenic origin in the both areas of Baengnyeong and SMA. Ratio of gas to particle partition of sulfate and nitrate were observed in both areas as more than 0.6 and 0.8, respectively, representing potential for formation of additional particulate sulfate and nitrate. The high-resolution spectra of organic aerosol (OA) were separated by three factors which were Primary OA(POA), Semi-Volatility Oxygenated Organic Aerosol (SV-OOA), and Low-Volatility OOA(LV-OOA) using positive matrix factorization (PMF) analysis. The fraction of oxygenated OA (SOA, ${\fallingdotseq}OOA$=SV-OOA+LV-OOA) was bigger than the fraction of POA in $NR-PM_1$. The POA fraction of OA in Seoul is higher than it of Baengnyeong Island, because Seoul has a relatively large number of primary pollutants, such as gasoline or diesel vehicle, factories, energy facilities. Potential source contribution function (PSCF) analysis revealed that transport from eastern China, an industrial area with high emissions, was associated with high particulate sulfate and organic concentrations at the Baengnyeong and SMA sites. PSCF also presents that the ship emissions on the Yellow Sea was associated with high particulate sulfate concentrations at the measurement sites.

• 한국산학기술학회논문지
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• 제13권1호
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• pp.227-235
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• 2012

이 연구에서는 최근 국내에서 개발된 보행용 기능성 신발 중 걷기 효율성을 변화시키는 복합적 기능성 신발(double rocker sole;CDR)과 negative-heel rocker sole(NR)형태 신발의 근육 활성도를 비교하였다. 연구대상은 하지정형 외과적 질환이 없는 40-50대 중년여성 11명을 대상(연령 $47.33{\pm}4.4$, 신장 $158.00{\pm}3.3$cm, 체중 $59.50{\pm}6.1$, BMI $23.80{\pm}1.8kg/m^2$)으로 하였다. 연구결과 좌,우측의 내측광근, 비복근, 반건양근에서는 근활성도의 수준은 통계적으로 유의한 차이가 나타나지 않았지만, CDR신발이 전경골근에서 통계적으로 유의하게 높은 결과가 나타났다(p<.05). 걷기운 동시 동일한 조건속에 운동을 실시할 경우 신발 밑창의 변화를 통해 인위적으로 운동량을 증가시킬 수 있을 것이다.

• Journal of Animal Science and Technology
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• 제61권5호
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• pp.260-271
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• 2019

The objective of this study was to determine the effect of different stocker management programs on skeletal muscle development and growth characteristics, satellite cell (SC) activity in growing-finishing beef cattle as well as the effects of SC-conditioned media on preadipocyte gene expression and differentiation. Fall-weaned Angus steers (n = 76; $258{\pm}28kg$) were randomly assigned to 1 of 4 stocker production systems: 1) grazing dormant native range (NR) supplemented with a 40% CP cottonseed meal-based supplement ($1.02kg{\cdot}steer^{-1}{\cdot}d^{-1}$) followed by long-season summer grazing (CON, 0.46 kg/d); 2) grazing dormant NR supplemented with a ground corn and soybean meal-based supplement fed at 1% of BW followed by short-season summer grazing (CORN, 0.61 kg/d); 3) grazing winter wheat pasture (WP) at high stocking density (3.21 steers/ha) to achieve a moderate rate of gain (LGWP, 0.83 kg/d); and 4) grazing winter WP at low stocking density (0.99 steers/ha) to achieve a high rate of gain (HGWP, 1.29 kg/d). At the end of the stocker (intermediate harvest, IH) and finishing (final harvest, FH) phases, 4 steers / treatment were harvested and longissimus muscles (LM) sampled for cryohistological immunofluorescence analysis and SC culture assays. At IH, WP steers had greater LM fiber cross-sectional area than NR steers; however, at FH, the opposite was observed (p < 0.0001). At IH, CORN steers had the lowest Myf-5+:Pax7+ SC density (p = 0.020), while LGWP steers had the most Pax7+ SC (p = 0.043). At FH, CON steers had the highest LM capillary density (p = 0.003) and their cultured SC differentiated more readily than all other treatments (p = 0.017). At FH, Pax7 mRNA was more abundant in 14 d-old SC cultures from HGWP cattle (p = 0.03). Preadipocytes exposed to culture media from proliferating SC cultures from WP cattle isolated at FH had more $PPAR{\gamma}$ (p = 0.037) and less FABP4 (p = 0.030) mRNA expression compared with NR cattle. These data suggest that different stocker management strategies can impact skeletal muscle growth, SC function, and potentially impact marbling development in growing-finishing beef cattle.