• Korean Journal of Environmental Biology
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• v.23 no.3 s.59
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• pp.221-227
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• 2005

The effects of light and $CO_2$ on the electrophysiological characteristics of guard cells in the intact leaf and isolated epidermis have been investigated. Fast hyperpolarization of guard cell apoplastic PD in the intact leaf was recorded reaching up to around 7 mV and 20 mV in response to light and $CO_2$. Whenever the experiments were attempted with isolated epidermis, there was no response to light and $CO_2$. In order to determine the influence of the mesophyll cells, the apoplastic PD of guard cells in isolated epidermis was measured in the presence of the mesophyll supernatant or the control medium. The apoplastic PD in isolated epidermis was hyperpolarized to -7mV, changing from -22mV to -29mV at 40 min. But, when isolated epidermis was incubated with the supernatant from mesophyll cells incubated in the light, the apoplastic PD in isolated epidermis was hyperpolarized to -19 mV, changing from -22 mV to -40.5 mV. $CO_2$ also caused a change of 0.1 to 0.3 pH unit in the intact leaf. However, this change was absent in isolated epidermis. A vibrating probe was used to detect the change in electrical currents at the surface of excised intact leaves and isolated epidermis. The reading of excised intact leaves in the dark was $0.5\muA\;cm^{-2},$ remaining steady until illuminated. Light increased the current on the surface of excised leaves to about $0.8\muA\;cm^{-2},$. However, light had no effect in the current on the surface of isolated epidermis. Apoplastic pH changes across the stomatal complex in response to light and dark were measured both in the intact leaves and isolated epidermis over the same time period using pH micro-electrodes. The guard cell wall of intact leaf was acidified to 2.5 pH unit, falling from pH 7.5 to pH 5.0 in the first 10 min. in the light. At the same time the guard cell wall pH of isolated epidermis fell from pH 7.5 to pH 7.0 at 10 min. The guard cell wall pH of isolated epidermis incubated in the mesophyll supernatant fell from pH 7.6 to pH 6.7 at 10 min. Likewise, It could be imagined that an electrical signal, chemicals and hormones propagated from the mesophyll in response to light and $CO_2$ could control a fast stomatal response.

• Parasites, Hosts and Diseases
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• v.44 no.3
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• pp.221-228
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• 2006

We conducted a study to compare the safety and tolerability of anti-relapse drugs elubaquine and primaquine against Plasmodium vivax malaria. After standard therapy with chloroquine, 30 mg/kg given over 3 days, 141 patients with P. vivax infection were randomized to receive primaquine or elubaquine. The 2 treatment regimens were primaquine 30 mg once daily for 7 days (group A, n = 71), and elubaquine 25 mg once daily for 7 days (group B, n = 70). All patients cleared parasitemia within 7 days after chloroquine treatment. Among patients treated with primaquine, one patient relapsed on day 26; no relapse occurred with elubaquine treatement. Both drugs were well tolerated. Adverse effects occurred only in patients with G6PD deficiency who were treated with primaquine (group A, n = 4), whose mean hematocrit fell significantly on days 7,8 and 9 (P= 0.015, 0.027, and 0.048, respectively). No significant change in hematocrit was observed in patients with G6PD deficiency who were treated with elubaquine (group B, n = 3) or in patients with normal G6PD. In conclusion, elubaquine, as anti-relapse therapy for P. vivax malaria, was as safe and well tolerated as primaquine and did not cause clinically significant hemolysis.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.4
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• pp.626-631
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• 2019

The policy-making and technological development for the supply expansion of eco-friendly automobiles has been continuing, but the internal combustion engines still accounts for about 95%. Also, in order to meet the stricter emission regulations of internal combustion engines based on fossil fuels, the proportion of after-treatments for vehicles and (ocean going) vessels is gradually increasing. This study is a basic study for the post-Euro-VI exhaust response of CNG buses, and it is to investigate the basic characteristics according to Pd substitution transition metal effect, catalyst volume effect and space velocity. A catalysts was prepared and tested using a model gas reactor. The NGOC catalyst with 3Pd exhibited the highest catalytic activity with 22% at $300^{\circ}C$, 48% at $350^{\circ}C$ and about 75% at $500^{\circ}C$. 3Co NGOC containing 3wt% of transition metal was excellent in oxidation ability, and it was small in size of 2nm, and the degree of catalyst dispersion was improved and de-NO/CO conversion was high. The volume of the NGOC-LNT-SCR catalyst system was optimal in the combination of 1.5+0.5+0.5 with a total score of 165, considering $de-CH_4/NOx$ performance and catalyst cost. For SV $14,000h^{-1}$, the $CH_4$ reduction performance was the highest at about 20%, while the SV $56,000h^{-1}$ was the lowest at about 5%. If the space velocity is small, the flow velocity decreases and the time remaining in the catalyst volume become long, so that the harmful gas was reduced.

• Journal of the Korean Chemical Society
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• v.52 no.2
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• pp.140-147
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• 2008

.A new approach for a cloud point extraction-electrothermal atomic absorption spectrometric method was used for determining bismuth. The aqueous analyte was acidified with sulfuric acid (pH 3.0-3.5). Triton X-114 was added as a surfactant and natriumdiethyldithiocarbaminat (Na-DDTC) was used as a complexing agent. After phase separation at 50oC based on the cloud point separation of the mixture, the surfactant-rich phasen was diluted using tetrahydrofuran (THF). Twenty microliters (20 L) of the enriched solution and 10 l of 0.1% (w/v) Pd(NO3)2 as chemical modifier were dispersed into the graphite tube and the analyte determined by electrothermal atomic absorption spectrometry. After optimizing extraction conditions and instrumental parameters, a preconcentration factor of 195 was obtained for a sample of only 10 mL. The detection limit was 0.04 ng ml-1 and the analytical curve was linear for the concentration range of 0.04-0.70 ng mL-1. Relative standard deviations were <5%. The method was successfully applied for the extraction and determination of bismuth in water samples.

• Journal of Periodontal and Implant Science
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• v.50 no.2
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• pp.74-82
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• 2020

Purpose: The aim of this cross-sectional study was to investigate the effect of scaling and root planing (SRP) on the expression of anti-inflammatory cytokines (interleukin [IL]-4, IL-9, IL-10, and IL-13) in the gingival crevicular fluid (GCF) of electronic cigarette users and non-smokers with moderate chronic periodontitis (CP). Methods: Electronic cigarette users and non-smokers with CP were included in the study. Full-mouth plaque and gingival indices, probing depth (PD), clinical attachment loss (CAL), and marginal bone loss (MBL) were assessed. The GCF was collected, and its volume and levels of IL-4, IL-9, IL-10, and IL-13 were assessed. These parameters were evaluated at baseline and 3 months after SRP. The sample size was estimated, and comparisons between groups were performed. P<0.05 was considered to indicate statistical significance. Results: Thirty-six electronic cigarette users (47.7±5.8 years old) and 35 non-smokers (46.5±3.4 years old) with CP were included. At baseline, there were no differences in plaque index (PI), PD, CAL, MBL, and GCF IL-4, IL-9, IL-10, and IL-13 between electronic cigarette users and nonsmokers. At the 3-month follow-up, there were no significant differences in PI, gingival index (GI), PD, CAL, and MBL in electronic cigarette users compared to baseline, while there were significant reductions in PI, GI, and PD among non-smokers. At the 3-month follow-up, GCF IL-4, IL-9, IL-10, and IL-13 levels were significantly elevated in both groups (P<0.05) compared to baseline. The increases in GCF IL-4, IL-9, IL-10, and IL-13 levels were significantly higher in non-smokers (P<0.05) than in electronic cigarette users at the 3-month follow-up. Conclusions: Levels of GCF IL-4, IL-9, IL-10, and IL-13 increased after SRP in electronic cigarette users and non-smokers with CP; however, the anti-inflammatory effect of SRP was more profound in non-smokers than in electronic cigarette users.

• Journal of Life Science
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• v.29 no.2
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• pp.191-197
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• 2019

Parkinson's disease (PD) is a progressive neurodegenerative disease that mainly affects motor system with clinical features such as bradykinesia, rigidity, tremor and abnormal posture. PD is characterized by the death of dopaminergic neurons in the substantia nigra pars compacta, which is associated with accumulation of oxidative stress and dysregulation of intracellular signaling pathway. Quercetin-3-O-glucuronide (Q3GA), a major metabolite of quercetin, has been reported to have neuroprotective effects. In this study, we examined the neuroprotective effect of Q3GA against 1-methyl-4-phenyl pyridinium ($MPP^+$)-induced neurotoxicity of PD and the underlying molecular mechanisms in SH-SY5Y cells. MTT and LDH assay showed that Q3GA significantly decreased $MPP^+$-induced cell death, which is accompanied by a reduction in poly (ADP-ribose) polymerase (PARP) cleavage. Furthermore, it attenuated $MPP^+$-induced intracellular reactive oxygen species (ROS) with the reduction of Bax/ Bcl-2 ratio. Moreover, Q3GA significantly increased the phosphorylation of Akt and cAMP response element binding protein (CREB), but it has no effects on the phosphorylation of extracellular signal-regulated kinase (ERK). Taken together, these results demonstrate that Q3GA significantly attenuates $MPP^+$-induced neurotoxicity through ROS reduction and Akt/CREB signaling pathway in SH-SY5Y cells. Our findings suggest that Q3GA might be one of the potential candidates for the prevention and/or treatment of PD.

• Journal of Korean Ophthalmic Optics Society
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• v.20 no.3
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• pp.377-384
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• 2015

Purpose: On this study, we measured and compared the dynamic stereoacuity by two-rods test (Howard-Dolman Test) and three-rods test. And we analyzed the correlation between PD and refractive error with dynamic stereoacuity. Methods: Dynamic stereoacuity of two-rods test and three-rods test at 2.5 m distance for 93 adults 93 (50 males, 43 females), mean age of $21.27{\pm}2.32$ (19~32) years old, were measured 5 times for two tests. Results: The mean of dynamic stereoacuity measured by two-rods test and three-rods test were $29.91{\pm}23.03sec$ of arc and $23.75{\pm}21.65sec$ of arc for total subjects, respectively. The mean of male and female were $36{\pm}22.38sec$ of arc and $22.28{\pm}23.79$, respectively. Three-rods test showed better dynamic stereoacuity than two-rods test, but there was no statistically significant difference (p>0.05). For the average standard deviation of PD between 60.63 mm~66.19 mm, dynamic stereoacuity fo two-rod test and three-rod test were $31.48{\pm}24.87sec$ of arc and $31.48{\pm}24.87sec$ of arc, respectively. The results showed statistically significant difference (p<0.05), but the relationship between dynamic stereoacuity and PD was not great. Comparison between two tests on the basis of refractive error, dynamic stereoacuity by three-rods test was better than by two-rods test with no significant difference between both tests (p>0.05) and there was little correlation between refractive error and two dynamic stereoacuity. Conclusions: Three-rods test showing lower stereoacuity than two-rods tests could measure the lower minimum threshold of dynamic stereoacuity. It was found that both tests can be applied to dynamic stereoacuity test as a standard test, and PD and refractive error was found that little effect upon the dynamic stereoacuity. PD and refractive error was found that little effect upon the dynamic stereoacuity.

• Korean Journal of Veterinary Service
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• v.33 no.1
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• pp.67-74
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• 2010

To reduce an economic loss by swine disease, this study was designed to provide helpful data which are particularly useful for each individual farm. From february to December 2009, a total of 18,173 slaughter pigs (612 herds) were randomly sampled, which were produced just in southern region of Gyeonggi-do. We examined all of them for the slaughter lesions of 8 kind diseases such as swine enzootic pneumonia (SEP), pleuritis (PL), pleuropneumonia (PP), white milk spot in liver (WMS), papular dermitis (PD), pericarditis (PC), ileitis (IL) and peritonitis (PT). Twenty four percentages (4431/18173 pigs) of the examined pigs had no lesions about 8 kind diseases. Among the pigs with lesions, the numbers of the pigs with just one lesion were 7,637(42%), followed by 4,551(25%) pigs with 2 lesions. Average prevalence of pigs were 56.5% (10288/18173 pigs) in SEP, followed by 34% in PL, 12.4% in PP, 10.1% in WMS, 6.1% in PD, 4.7% in PC, 0.1% in IL and PT, respectively. Each prevalence of SEP, PL, PP and PD was higher in spring than in winter, respectively (P<0.01). Among the pigs (n=6,105) with 2 or more than 2 kinds of lesions the top (55.5%) was the pigs with SEP and PL, and the second was 1,179 (19.3%). Swine enzootic pneumonia was considered as one of the more likely risk factors for initiation or/and acceleration of other diseases such as PL, PP, WMS and PD. The lesion of SEP was relatively severe since the pigs with late stage were more (7,277 pigs) than those with early stage.

• The Journal of Korean Academy of Prosthodontics
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• v.36 no.4
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• pp.566-580
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• 1998

Implant-supported overdenture is known as a useful appliance, instead of using the conventional complete denture, for better retention and stability. In this study 4 types of materials such as, gold bar/plastic clip(group AuP), gold bar/metal clip(group AuM), palladium bar/plastic clip(group PdP), and palladium bar/metal clip (group PdM) were used to evaluate the retention forces according the type of clips and alloys used for bar fabrication, in the Hader bar system. Repeated insertions and removals of overdenture were conducted in each group. and the retention forces were measured and compared the data of each group according to the number of insertion and removal. The obtained results were as follows, 1. In the comparison of retention forces according to type of bar-clip, retention was increased in the order of group AuM, PdM, PdP AuP. and the retention force of group AuM was significantly increased compared with those of others (p<0.05). 2. In the comparison of retention forces according to the number of insertion, only group PdP showed significant decrease in retention(p<0.05). 3. In the comparison of retention forces according to the type of bar and clip. there was no significant difference in the type of bar, but the retention of plastic clip was significantly higher than that of metal clip when Au bar was used(p<0.05). 4. In the observation of the bar surface, group AuM using Au bar and metal clip showed the most scratches among bar groups.

• Molecules and Cells
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• v.39 no.7
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• pp.543-549
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• 2016

MicroRNAs (miRNAs) have been reported to be involved in many neurodegenerative diseases. The present study focused on the role of hsa-miR-144-3p in one of the neuro-degenerative diseases, Parkinson's disease (PD). Our study showed a remarkable down-regulation of miR-144-3p expression in 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP)-treated SH-SY5Y cells. MiR-144-3p was then overexpressed and silenced in human SH-SY5Y cells by miRNA-mimics and miRNA-inhibitor transfections, respectively. Furthermore, ${\beta}$-amyloid precursor protein (APP) was identified as a target gene of miR-144-3p via a luciferase reporter assay. We found that miR-144-3p overexpression significantly inhibited the protein expression of APP. Since mitochondrial dysfunction has been shown to be one of the major pathological events in PD, we also focused on the role of miR-144-3p and APP in regulating mitochondrial functions. Our study demonstrated that up-regulation of miR-144-3p increased expression of the key genes involved in maintaining mitochondrial function, including peroxisome proliferator-activated receptor ${\gamma}$ coactivator-$1{\alpha}$(PGC-$1{\alpha}$), nuclear respiratory factor 1 (NRF-1) and mitochondrial transcription factor A (TFAM). Moreover, there was also a significant increase in cellular ATP, cell viability and the relative copy number of mtDNA in the presence of miR-144-3p overexpression. In contrast, miR-144-3p silencing showed opposite effects. We also found that APP overexpression significantly decreased ATP level, cell viability, the relative copy number of mtDNA and the expression of these three genes, which reversed the effects of miR-144-3p overexpression. Taken together, these results show that miR-144-3p plays an important role in maintaining mitochondrial function, and its target gene APP is also involved in this process.