• 공업화학
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• 제8권5호
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• pp.715-721
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• 1997

$W_1/O/W_2$ 다중유화의 내부수상($W_1$)에 전해질인 $MgSO_4$를 모델약물로 주입하여 안정성과 약물방출 거동을 현미경관찰, 점도 및 전도도의 변화를 통해 관찰하였다. 내상에 약물을 도입함으로써 내부와 외부수상간의 삼투압차를 유발하여 다중유화계의 불안정성을 초래하였으며 이를 완화하기 위하여 외부수상($W_2$)에 글루코즈를 첨가하여 효과를 살펴본 결과 글루코즈의 유효삼투압 당량이 내부에 포함된 약물의 삼투압 당량과 유사해짐에 따라 안정성이 향상되었을 뿐아니라 초기 약물방출 속도도 글루코즈 농도에 의해 조절할 수 있음을 발견하였다. 이는 삼투압차에 의한 수분 이동시 친수성 계면활성제를 동반하여 내부수상/오일상 계면을 파괴하는 것을 방지하기 때문으로 보인다. 또한 이와같은 현상은 오일상이 cetostearyl alcohol에 의하여 친수화되었을 때 뚜렷하게 나타났다.

• 한국작물학회지
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• 제44권3호
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• pp.263-266
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• 1999

Tobacco (Nicotiana tabacum L. ‘KF109’) seeds were primed in polyethylene glycol 6000 (PEG 6000) solutions to determine a) what osmotic potential of the solution would be optimal for priming, i.e., critical potential level for preventing germination, and b) what temperature and duration would be the most effective in priming. The germination was completely prevented below -0.8 MPa of PEG 6000, that indicates a optimum water potential for seed priming. Seeds were primed for 0, 1, 2, 3, 5, 10 and 15 days at 15, 20 and $25^{\circ}C$, respectively, under the-0.8 MPa PEG 6000 solution to find out the most effective temperature and duration for priming. The effectiveness of priming, particularly in germination speed, was observed more distinctly when the primed seeds were germinated at 15$^{\circ}C$ than 2 5$^{\circ}C$. The greatest reduction of the time to 50% germination (T/sob 50/) was when the seeds were primed at $25^{\circ}C$. The reduction rate of the $T_{50}$ was rapid when primed from 1 day to 8 days and then slowed down in the seeds primed for longer than 8 days. The time from 10 to 90% germination ( $T_{10-90}$ increased in the primed seeds for longer than 8 days which showed the reversed effect of synchronous germination. However, $T_{50}$ was reduced continuously in the seeds even primed over 8 days. Thus, the optimum condition for tobacco seeds priming with PEG 6000 solution was -0.8 MPa in osmotic potential of the solution at $25^{\circ}C$ for 8 days.ays.

• Reproductive and Developmental Biology
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• 제37권4호
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• pp.213-217
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• 2013

The objective of this study was to investigate the effect of bacterial contamination on elapsed time after preservation on boar semen. Known numbers of Escherichia coli (E. coli) were inoculated to freshly ejaculated semen and sperm parameters such as viability, motility, agglutination, acrosome integrity and hypo-osmotic swelling test were performed during 7 days of liquid preservation. Semen samples were prepared using antibiotic free BTS extender and 4 different levels of E. coli were treated to semen with following concentrations; 3,000, 5,000, 7,000, 10,000 CFU/ml of sperms. Semen samples were preserved at $17^{\circ}C$ for 7 days in semen storage until analyzed. Aliquots were subjected to measure the sperm viability, motility and agglutination using computer assisted sperm analysis (CASA) system, acrosome integrity was performed using chlortetracycline (CTC) staining method and hypo-osmotic swelling test was performed using hypotonic solution from day 1 (day of semen collection) to 7. Detrimental effects on sperm motility and viability were observed 3 days after preservation at the level of 5,000 CFU/ml (p<0.05). Percentage of sperm abnormality was higher (p<0.05) in over 5,000 CFU/ml groups. Sperm agglutination rate was also significantly higher (p<0.05) in groups of 5,000 and 7,000 CFU/ml. The rate of acrosome reacted sperm was higher as preservation time goes in all the samples but the pattern was clearly higher among E. coli contaminated groups (p<0.05). The sperm membrane integrity in terms of hypo-osmotic test, E. coli affects little compared to other sperm parameters. The deleterious effects observed due to the bacterial contamination in semen suggest that importance of hygiene protocol to minimize the bacterial contamination during semen collection and processing.

• 한국식품과학회지
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• 제30권2호
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• pp.348-355
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• 1998

건조키위의 제조시 건조에 의한 품질열화를 줄이기 위한 전처리공정으로서 삼투공정을 행하여 부분실시 계획법으로 실험계획을 수립한 후 반응표면분석법으로 최적화를 수행하여 최적조건을 얻고자 하였다. 삼투건조시 침지온도와 당농도 그리고 침지시간을 독립 변수로 하고 수분함량, solid gain, weight reduction, moisture loss, 적정산도, 당도, vitamin C를 반응변수로 하였다. 삼투건조 시 물질이동의 특성은 침지온도, 농도, 시간이 길어질수록 증가하는 것으로 나타났으며, 수분함량은 침지온도, 농도, 시간이 증가할수록 낮은 값을 보였고 당도는 침지온도와 농도 및 시간이 증가함에 따라 증가하였다. 적정산도와 vitamin C는 낮은 온도와 고농도의 처리에서 당의 보호작용으로 손실이 적게 나타났다. 수립된 회귀모형에 대한 적합성 결여분석 결과 반응변수 모두 유의성이 없어(P>0.05) 수립된 반응표면 모형이 통계적으로 유의하다고 할 수 있었으며 다중회귀분석 결과 일차항은 유의성이 인정되었다. 독립변수의 영향은 온도와 농도보다 유의성이 있었으나 시간에 대해서는 반응변수 모두 유의성이 인정되지 않았다. 독립변수중 가장 영향이 적은 침지시간인 1.5시간으로 고정하고 온도와 농도만을 변수로하여 수분함량을 $66{\sim}69%$로 하고, 당도와 vitamin C함량을 각각 $24^{\circ}Brix,\;23mg%$이상으로 하는 온도와 농도는 $34{\sim}39^{\circ}C,\;52{\sim}58^{\circ}Brix$로 나타나, 건조키위 제조를 위한 삼투처리의 최적조건을 $37^{\circ}C,\;55^{\circ}Brix$, 1.5시간으로 결정할 수 있었다.항균 효소제인 lysozyme을 분리하는데 매우 효과적인 방법이었다.제로 재차 이용할 경우 비드가 일정한 크기를 갖고, 감소한 표면적과 같은 양의 새로운 비드를 첨가한다면 사용된 비드의 재활용 가능성도 있다고 사료되었다.로 제조된 간장의 구수한 맛, 신맛, 짠맛과 종합적 기호도에서 유의차가 있어서 CM-메주로 제조한 간장보다 우수하였다. MCM-메주로 제조된 간장이 성분과 기호도에 있어서도 CM-메주로 제조된 간장보다 우수한 결과를 보였다. 일본인의 우리나라 전통적인 김치에 대한 종합적인 기호도는 염농도 2.03%, 2.63%, 1.07%의 김치 순으로 아주 싱거운 김치는 선호하지 않음을 알 수 있었다.{\;}8%+{\;}CO_2{\;}15%$ 조건이 보다 적합하였다.신증후군 재발을 경험한 응답자가 9명, 백신접종에도 불구 해당 질병 발병을 경험한 접종자가 3명, 생백신 접종 후 백신 균주에 의한 발병을 경험한 접종자가 2명이었다. 결론 : 국내의 소아 신장학 전문가들은 일반 소아에서 권장되는 예방접종 지침과는 다른 수정된 방식에 따른 예방접종을 실시하고 있었으나 아직 질병 경과와 스테로이드 사용에 따른 접종 시기에 다양성을 보이고 있었고, 또한 예방접종 후의 부작용을 경험한 경우도 다수 있었다. 따라서 향후 다수의 소아를 대상으로 한 전향적인 연구를 통하여 소아 신질한 환아에서 추천되는 예방접종 지침을 확립할 필요가 있다고 사료된다. 생리활성효과에 손색없는 것으로 판단되고, 이러한 기능성에 기초하여 chocolate, 음료 등의 식품이나 의약품의 기능성 소재로서의 산업적 응용 가능성이 높은 것으로 사료된다.대장균군이 역시 난각에서 가장 높은 빈도로 분리되었고, 난황(Yolk)에서는 극히 낮은 수준의 세균오염도를 보였다. 다양한 동물종유래 S. aureus

• Applied Biological Chemistry
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• 제49권4호
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• pp.281-286
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• 2006

Tolaasin은 Pseudomonas tolaasii에 의해 생성된 분자량 1,985 Da의 펩티드로서 재배버섯에 갈반병을 유발하는 원인 독소이다. Tolaasin은 곰팡이, 세균, 식물세포 뿐만 아니라 적혈구의 원형질막에 이온통로를 형성하여 세포를 파괴한다. $Zn^{+2}$는 tolaasin의 활성을 저해함이 알려졌으나, 자세한 기작은 밝혀지지 않았다. 따라서, 본 연구에서는 tolaasin의 이온통로 형성에 대한 분자기작을 밝히기 위하여, 적혈구 용혈현상에 대한 $Zn^{+2}$의 저해효과를 조사하였다. $Zn^{+2}$와 $Cd^{+2}$은 tolaasin의 용혈활성을 농도의존적으로 저해하였으며, Ki 값은 각각 170 ${\mu}M$과 20 mM 이었다. $Zn^{+2}$의 저해효과는 EDTA의 첨가로 제거되어 $Zn^{+2}$의 효과가 가역적임을 보여준다. 한편, tolaasin과 함께 삼투억제제인 PEG 2000을 가하였을 때, 용혈현상은 나타나지 않았다. 적혈구를 원심분리로 회수하고 PEG 2000을 제거한 후, 신선한 반응용액에 현탁하였을 때, 용혈현상은 즉시 관측되었다. 그러나, 이때에도 $Zn^{+2}$가 존재시에는 용혈현상이 억제되었으며, 이것은 삼투억제제의 처리중에 이미 이온통로가 만들어졌음을 의미한다. 이러한 결과는 $Zn^{+2}$가 tolaasin의 세포막 결합 및 이온통로 형성에는 영향이 적으며, 형성된 이온통로의 활성을 저해함을 보인다.

• Journal of Electrochemical Science and Technology
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• 제9권2호
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• pp.85-92
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• 2018

Olivine structure of $LiFePO_4$ (LFP) is one of the most commonly used materials in aqueous rechargeable lithium batteries (ARLBs), and can store and release charge through the insertion/de-insertion of $Li^+$ between LFP and FP. We have fabricated LFP and LFP/FP electrodes on titanium paper and studied their electrochemical properties in 2 M $Li_2SO_4$. The LFP/FP electrode was determined to be a suitable electrode for electo-ostmotic pump (EOP) in terms of efficiency in water and 0.5 mM $Li_2SO_4$ solution. Experiments to determine the effect of cations and anions on the performance of EOP using LFP/FP electrode have shown that $Li^+$ is the best cation and that the anion does not significantly affect the performance of the EOP. As the concentration of $Li_2SO_4$ solution was increased, the current increased. The flow rate peaked at $4.8{\mu}L/30s$ in 1.0 mM $Li_2SO_4$ solution and then decreased. When the EOP was tested continuously in 1.0 mM $Li_2SO_4$ solution, the EOP transported approximately 35 mL of fluid while maintaining a stable flow rate and current for 144 h.

• Journal of Trauma and Injury
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• 제25권4호
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• pp.209-216
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• 2012

Purpose: The objectives of this study are to classify chronic subdural hematomas based on brain computerized tomographic scan (CT scan) findings and to determine the mechanism of evolution and treatment methods. Methods: One hundred thirty-nine patients who were diagnosed with a chronic subdural hematoma and who available for follow up assessment 6 months post-surgery were analyzed retrospectively. The presence of trauma and past medical history were reviewed and evaluation criteria based on brain CT scan findings were examined. Results: Initial brain CT scans revealed a chronic subdural hematoma in 106 patients, a subdural hygroma in 24 patients, and an acute subdural hematoma in 9 patients. In all cases where the initial acute subdural hematoma had progressed to a chronic subdural hematoma, final was a hypo-density chronic subdural hematoma. In case where the initial subdural hygroma had progressed to a chronic subdural hematoma, the most cases of hematoma were hyper-density and mixed-density chronic subdural hematoma. In total, 173 surgeries were performed, and they consisted of 97 one burr-hole drainages, 70 two burr-hole drainages and 6 craniotomies. Conclusion: This study demonstrates that rebleeding and osmotic effects are mechanisms for enlarging of a chronic subdural hematoma. In most cases, one burr-hole drainage is a sufficient for treatment. However, in cases of mixed or acute-on-chronic subdural hematomas, other appropriate treatment strategies are required.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• 제25권2호
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• pp.82-88
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• 2014

Objectives : The aim of our study was to investigate association of norepinephrine transporter gene (SLC6A2) polymorphism and side effects of osmotic-release oral system methylphenidate (OROS MPH) in children with attention-deficit hyperactivity disorder (ADHD). Methods : We recruited drug naive children with ADHD (N=97). We administered OROS MPH by tolerable dosage. At week 8 of treatment, parents completed the Barkley's side effect rating scale. We analyzed two SLC6A2 single nucleotide polymorphisms (SNPs), rs192303 and rs3785143, with blood of subjects. We compared the frequency and severity of each side effect among SLC6A2 genotypes of 2 SNPs. Results : In the analysis of frequency of each side effect, irritability differed according to rs192303 and rs3785143 genotype. In comparisons of severity, talking less and disinterest differed according to rs192303 genotype. In the case of rs3785143, severities of disinterest and irritability were involved with genotype. Conclusion : Side effects of OROS MPH showed an association with SLC6A2 genotype.

• The Korean Journal of Physiology
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• 제21권2호
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• pp.157-167
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• 1987

Benzyl alcohol is known to have dual effect on the red blood cell shape change. At low concentration up to 50 mM benzyl alcohol transformed the shape from discocyte to stomatocyte by preferent binding to the inner hemileaflet, however, at higher concentratransformed the shape from discocyte to stomatocyte by preferential binding to the inner monolayer, however, at higher concentration above 50 mM benzyl alcohol transformed to echinocyte by affecting both monolayers. These results suggest that the effect of benzyl alcohol on the red blood cell shape and $Ca^{++}$ transport across cardiac cell membranes to assess the effects of the drug on the structures and functions of the biological cell membranes. The results are as follows: 1) Benzyl alcohol up to 40 mM caused progressive stomatocytic shap change of the red blood cell but above 50 mM benzyl alcohol caused echinocytic shape change. 2) Benzyl alcohol up to 40 mM inhibited both osmotic hemolysis and osmotic volume change of the red blood cell in hypotonic and hypertonic NaCl solutions, respectively. 3) Benzyl alcohol inhibited both Bowditch Staircase and Wood-worth Staircase phenomena at rat left auricle. 4) Benzyl alcohol at concentration of 5 mM increased $Ca^{++}-ATPase$ activity of red blood cell ghosts slightly but above S mM benzyl alcohol inhibited the $Ca^{++}-ATPase$ activity. 5) Benzyl alcohol at concentrations of 5 mM and 10 mM increased $Ca^{++}-ATPase$ activity slightly at rat gastrocnemius muscle S.R. but above 10 mM benzyl alcohol inhibited the $Ca^{++}-ATPase$ activity. Above results indicate that benzyl alcohol inhibit water permeability and $Ca^{++}$ transport across cell membranes in part via effects on the fluidity and transition temperatures of the bulk lipid by preferential intercalation into cytoplasmic monolayer and in part via other effect on the conformational change of active sites of the $Ca^{++}-ATPase$ molecule extended in cytoplasmic face.

• 한국작물학회지
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• 제45권1호
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• pp.50-54
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• 2000

The elongation of mesocotyl and coleoptile plays important roles in the seedling emergence and stand establishment of dry direct-seeded rice. Experiments were carried out to elucidate the effects of seed-presoaking treatments of GA$_3$ and some inorganic salts on the mesocotyl, and coleoptile elongation of rice. Seed-soaked GA$_3$ promoted the elongation of mesocotyl, but little effect on the coleoptile elongation. The stimulation effects of GA$_3$ were found to be enhanced by addition of CaCl$_2$ However, the sole treatment of CaCl$_2$ showed no stimulating effect on the mesocotyl and coleoptile elongation. Mesocotyl elongation was most prominent in the combined treatments of 50ppm GA$_3$ with 100 mM CaCl$_2$. The synergistic effects of GA$_3$ and CaCl$_2$ on mesocotyl elongation varied with varietal groups. The stimulating effects of GA$_3$ were enhanced significantly by the addition of CaCl$_2$ in japonica varieties, Dongjinbyeo, Ilpumbyeo and Milyang 95, and tall indica variety, Labelle, but not in semidwarf Tongil type varieties, Tongilbyeo, Milyang 23, and Nampungbyeo, and semi-dwarf indica, Short Labelle. The promoting effects of GA$_3$ on the mesocotyl elongation were decreased in proportion to the lowered osmotic potential by PEG 6000 on the contrary to CaCl$_2$ This implies that the synergistic effects of CaCl$_2$ with GA$_3$ on mesocotyl elongation was not caused by osmotic potential lowered by CaCl$_2$ addition but by the salt itself. Salts such as Ca(NO$_3$)$_2$, MgCl$_2$ BaCl$_2$, NaCl, KCl and KNO$_3$ showed the synergistic effects with GA$_3$ on mesocotyl elongation as well. The degree of synergistic effects showed no differences among salts tested, implying that there is no specificity of ions constituting the salts.