• 기본간호학회지
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• 제21권3호
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• pp.226-234
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• 2014

Purpose: This study was done to present guidelines for deciding appropriate times for measuring blood pressure (BP) in patients with neurological disorders who had surgery due to brain damage. Method: It was a repeated measures-experimental research on time variants in BP after nursing care. SBP (Systolic BP) and DBP (Diastolic) were measured every 2 minutes up to 5 times using an EKG patient monitor. Measured data were analyzed using repeated measures ANOVA and paired t-test. Results: For suctioning, there were significantly higher differences for SBP averages after 2 min. (138mmHg, p<0.01) and 4 min. (133mmHg, p<0.01) compared to before suctioning (120mmHg). For position change, there were significant differences in SBP averages after 2 min. (136mmHg, p<0.01) and 4 min. (130mmHg, p=0.01) compared to before changing position (121mmHg). For position change followed by suctioning there were significant differences in SBP averages after 2 min. (136mmHg, p<0.01), 4 min. (136mmHg, p<0.01) and 6 min. (125mmHg, p=0.003) compared to before the interventions (121mmHg). Conclusions: Results indicate that there are significant differences in SBP and DBP over time during nursing interventions, suggesting clinical measurement of BP after 6 min. or 8 min. be done for patients with neurological disorders in neurosurgery clinics.

• Toxicological Research
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• 제29권4호
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• pp.235-240
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• 2013

Extracellular accumulation of amyloid beta protein ($A{\beta}$) plays a central role in Alzheimer's disease (AD). Some metals, such as copper, lead, and aluminum can affect the $A{\beta}$ accumulation in the brain. However, the effect of mercury on $A{\beta}$ accumulation in the brain is not clear. Thus, this study was proposed to estimate whether mercury concentration affects $A{\beta}$ accumulation in PC12 cells. We treated 10, 100, and 1000 nM $HgCl_2$ (Hg) or $CH_3HgCl_2$ (MeHg) for 48 hr in PC12 cells. After treatment, $A{\beta}_{40}$ in culture medium increased in a dose- and time-dependent manner. Hg and MeHg increased amyloid precursor protein (APP), which is related to $A{\beta}$ production. Neprilysin (NEP) levels in PC12 cells were decreased by Hg and MeHg treatment. These results suggested that Hg induced $A{\beta}$ accumulation through APP overproduction and reduction of NEP.

• 한국재료학회지
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• 제26권6호
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• pp.298-305
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• 2016

In this work, recent progress on graphene/metal oxide composites as advanced materials for $HgCl_2$ and $CO_2$ capture was investigated. Density Functional Theory calculations were used to understand the effects of temperature on the adsorption ability of $HgCl_2$ and water vapor on $CO_2$ adsorption on CaO (001) with reinforced carbon-based nanostructures using B3LYP functional. Understanding the mechanism by which mercury and $CO_2$ adsorb on graphene/CaO (g-CaO) is crucial to the design and fabrication of effective capture technologies. The results obtained from the optimized geometries and frequencies of the proposed cluster site structures predicted that with respect to molecular binding the system possesses unusually large $HgCl_2$ ($0.1-0.4HgCl_2g/g$ sorbent) and $CO_2$ ($0.2-0.6CO_2g/g$ sorbent) uptake capacities. The $HgCl_2$ and $CO_2$ were found to be stable on the surface as a result of the topology and a strong interaction with the g-CaO system; these results strongly suggest the potential of CaO-doped carbon materials for $HgCl_2$ and $CO_2$ capture applications, the functional gives reliable answers compared to available experimental data.

• 대한화학회지
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• 제51권4호
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• pp.324-330
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• 2007

수은(II) 이온 센서로 이온투과 담체로서 bis(benzoylacetone) propylenediimine (H2(BA)2PD)을 근간으로 하는 새로운 이온 선택 PVC 막 전극이 개발하였다. 이 전극은 좋은 감응 특성을 보였고, 29.8±0.75 mV/10의 Nernstian 기울기로 부터 1.0×10-6-1.0×10-1 M 수은(II) 이온 농도 범위에서 선형 Emf vs. log[Hg2+]를 보였다. pH 2.5-11.5에서 검출한계는 2.2×10-7 M Hg(II)를 보였다. 다수의 전위 간섭이온에의 수은(II)이온 대한 선택 농도에 대해 역시 연구되었다. 이 센서는 다른 전하와 함께 많은 수의 양이온에 있어 수은(II)이온에 대해 고선택성을 보였다. 이 센 서는 60초 안에 빠는 감응을 보이며 화학적으로 불활성인 것을 알아 내었고 3개월 동안 좋은 재현성을 보였다(S = 0.27 mV). 이 전극은 실제 시료에서 수은(II)이온 의 분석에 대해 서도 만족할 만한 결과를 얻었다.

• 한국환경보건학회:학술대회논문집
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• 한국환경보건학회 2005년도 국제학술대회
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• pp.73-83
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• 2005

Higher methylmercury (MeHg) accumulation and susceptibility to toxicity in the fetus than in the mother at parturition is well known. However, the difference in MeHg exposure to fetus and offspring throughout gestation and suckling is not well established. In the human, the effects of MeHg exposure on pregnant and breast-feeding women remain an important issue for elucidation, especially those of continuous uptake in high-fish-consumption populations. The purpose of this paper was to evaluate the difference in MeHg exposure to fetus and offspring throughout gestation and lactation using our recent animal and human studies data. In the animal study, adult female rats were given a diet containing 5 ${\mu}$g/g Hg (as MeHg) for 8 weeks. Then they were mated and subsequently given the same diet throughout gestation and suckling. On embryonic days 18, 20, 22 and at parturition, the concentrations of Hg in the brains of fetus were approximately 1.5-2.0 times higher than those in the mothers. However, during the suckling period Hg concentrations in the brain rapidly declined to about 1/10 of that during late pregnancy. Hg concentrations in blood also decreased rapidly after birth. In human study, Hg concentrations in red blood cells (RBCs-Hg) in 16 pairs of maternal and umbilical cord blood samples were compared at birth and 3 months of age after parturition. RBCs-Hg concentration in the umbilical cords was about 1.6 times higher than those in the mothers at parturition. However, all the infants showed declines in Hg concentrations throughout the breast-feeding period. The Hg concentration in RBCs-Hg at 3 months of age was about half that at birth. Both the animal and human studies indicated that MeHg exposure to the fetus might be especially high but it dramatically decreases during the suckling period. Therefore, close attention should be paid to the gestation rather than the breast-feeding period to avoid the risk of MeHg to human infants.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 춘계학술대회 논문집
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• pp.54-56
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• 2005

Fabrication of c-axis oriented $(Hg_{0.75}Rc_{0.25})Ba_2Ca_2Cu_3O_y$ thick fabricated has been attempted using Ni substrates with the buffer layer of Cr or NiO. Coexistence of $(Hg_{0.75}Rc_{0.25})Ba_2Ca_3Cu_4O_y$ pellets wad found to stabilize $(Hg_{0.75}Rc_{0.25})Ba_2Ca_2Cu_3O_y$ phase of the tape. The c-axis oriented tapes were reproducibly obtained on the NiO/Ni substerate and they recorded high $B_{irr}$ at 77K.$(Hg_{0.75}Rc_{0.25})Ba_2Ca_2Cu_3O_y$ 1223.

• Applied Biological Chemistry
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• 제40권4호
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• pp.347-351
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• 1997

군산 장항 해안지역의 중금속 오염실태를 파악하기 위하여 해수, 해안저질토 및 어패류중 중금속함량을 조사한 결과는 다음과 같다. 해수중 중금속 평균함량은 Pb 2.35, Cd 0.52, Cu 2.09, Zn 13.65, $Hg\;0.24\;{\mu}g/l$이었다. 해안저질토중 중금속 평균함량은 Pb 19.49, Cd 0.15, Cu 9.31, Zn 20.07, Hg 0.136 mg/kg이었으며, 각 조사지점 별로 중금속함량간에 차이를 나타내고 있었다. 어류의 건물중 Pb, Cd, Cu, Zn, Hg평균함량은 풀망독(Acantogobius hasta)에서 각각 1.08, 0.05, 2.24, 58.14, 0.151 mg/kg이었으며, 숭어(Mugil cephalus)에서 각각 1.63, 0.05, 1.51, 32.69, 0.065 mg/kg으로 나타났다. 풀망독 및 숭어에서 Pb, Cu의 경우는 비슷한 축적률을 보이고 있으나 풀망독이 숭어에 비해 Zn과 Hg에서 2배 이상 높은 축적률을 보였다. 패류의 건물중 Pb, Cd, Cu, Zn, Hg 평균함량은 가무락(Cyclina sinensis)에서 각각 1.03, 1.23, 6.83, 75.83, 0.071 mg/kg이었으며, 반지락(Ruditpes philippinarum)에서 각각 0.93, 0.86, 5.90, 52.16, 0.074 mg/kg으로 나타났다. 인근 해수중 평균 중금속함량을 기준으로 계산된 중금속 축적률 순위는 패류종에 관계없이 Cu>Cd>Zn>Pb>Hg 순이었다.

• BMB Reports
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• 제31권2호
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• pp.189-195
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• 1998

Methylmercury (MeHg), which is widely distributed in the environment, is well known for both its acute and chronic poisoning effects on the human health; however, the precise biochemical mechanisms by which this compound elicits its toxicity in a cellular level are still poorly understood. To examine whether MeHg-induced liver injury involves activation of Phospholipase $A_2$ ($PLA_2$), the $PLA_2$ activity of control and MeHg-administrated livers was measured. MeHg stably enhanced a liver form of cytosolic $PLA_2$ activity, which exhibited several biochemical properties similar to those of the 100 kDa $cPLA_2$, except in its elution profile of a DEAE-5PW HPLC, and it migrated as a molecular weight of 80 kDa in Western blot analysis. This blotting analysis also indicated that the MeHg-induced enhancement of the activity could be due to the increase in the amount of the enzyme protein rather than a stable modification of the enzyme such as phosphorylation. Our data also showed the higher myeloperoxidase activity in MeHg-administrated liver than in the control, suggesting that this increase in the amounts of the 80 kDa $PLA_2$ and its activity may be resulted from infiltration of neutrophils into the liver during a hepatic injury process such as MeHg-induced inflammation. Taken together, these data suggest that MeHg-induced liver injury may be mediated by activation of the 80 kDa form of liver cytosolic $PLA_2$.

• 한국독성학회:학술대회논문집
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• 한국독성학회 2006년도 추계학술대회
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• pp.46-54
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• 2006

The methylmercury (MeHg) is a toxic environmental pollutant, causing serious neurological and developmental effects in humans. Recent epidemiological studies have indicated that ingestion of MeHg in fish during pregnancy can result in neuroethological effects in the offspring. However, the mechanism underlying the MeHg-toxicity is not fully understood. To elucidate the mechanisms of toxicity of MeHg and of defense against MeHg, we searched for factors that determine the sensitivity of yeast cells to MeHg, and found that overexpression of Cdc34, a ubiquitin-conjugating enzyme (E2) that is a component of the ubiquitin-proteasome (UP) system, induces a resistance to MeHg toxicity in both yeast and human cells. The UP system is involved in the intracellular degradation of proteins. When Cdc34 is overexpressed in cells, ubiquitination reactions are activated and the degradation of certain proteins by the UP system is enhanced. Therefore, it seems likely that certain as-yet-unidentified proteins that increase MeHg toxicity might exist in cons and that toxicity might be reduced by the enhanced degradation of such proteins, mediated by the UP system, when Cdc34 is overexpressed. SCF ubiquitin-ligase is a component of UP system and consists of Skpl, the scaffold protein Cdc53, the RING-finger protein Hrt1, and one member of the family of F-box proteins. The F-box proteins directly bind to the substrates and are the determinants of substrate specificity of SCF. Therefore, we searched for the f-box protein that cofers resistance to MeHg, and found that overexpression of Hrt3 or Yi1224w induced resistance to MeHg toxicity in yeast cells. Since the protein(5) that enhance toxicity of MeHg might plausibly be induced in substrates of both f-box proteins, we next searched for substrate proteins that are recognized by Hrt3 or Y1r224w using two-hybrid screen. We found that Did3 or Crsl interacts with Hrt3; and Eno2 interacts with Yir224w. The yeast cells that overexpressed each those proteins showed hypersensitivity to MeHg, respectively, indicating that those proteins enhance the MeHg toxicity. Both Dld3 and Eno2 are proteins involved in the synthesis of pyruvate, and overexpression of both proteins might induce increase in interacellular levels of pyruvate. Deletion of Yi1006w that transports pyruvate into the mitochondria induced aresistance to MeHg. These results suggest that the promotion of the pyruvate irdlowinto the mitochondria might enhance MeHg toxicity. This study providesimportant keyfor the elucidauon of the molecular mechanism of MeHg toxicity.

• 한국전기전자재료학회논문지
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• 제16권11호
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• pp.969-974
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• 2003

HgGa$_2$S$_4$ single crystals were grown by the chemical transport reaction method. The HgGa$_2$S$_4$ single crystal crystallized into a defect chalcopyrite structure (I 4). The lattice constants of the single crystal were found to be a = 5.635 $\AA$ and c = 10.473 $\AA$. The direct and indirect optical energy gaps were found to be 2.84eV and 2.78eV, respectively. Photoluminescence peaks of HgGa$_2$S$_4$ single crystal were observed at 2.37 eV, 2.18 eV, and 1.81 eV. In the single crystal, the donor level of 0.25 eV, the acceptor levels of 0.97 eV and 0.41 eV were obtained by TSC, PICTS, and absorption measurements. The photoluminescence peaks were analyzed to relate to the indirect conduction band, the donor level, and the acceptor levels.