채소내의 칼륨은 만성 신부전 환자에게 악영향을 주는 것으로 알려져 있다. 하지만 채소는많은 다른 영양 물질 또한 함유하고 있으므로, 이러한 환자들에게 채소의 섭 취는 불가피하다. 본 연구는 완전제어형 식물공장에서 신장환자들을 위해 적합한 저칼륨 상추 개발을 위해 수행되었다. 본 연구에 사용된 상추 품종은 ‘찰스’ 품종이 었다. 완전제어형 식물공장에서 정식 후 28일간 수행되었으며, 광 환경은 LED (W:R, 9:1), 일장 16시간, 200μmol·m-2·s-1 이었고 재배 온도, 상대습도와 이산화탄 소 농도는 각각 15-21oC, 65%와 600-650mg·L-1 이었다. 1차 실험에서 배양액은 수확 전 1주전과 2주전에 칼륨농도를 10%와 5%로 낮게 처리하였고, 이를 토대로 2차실 험의 처리는 수확 전 2주전 5%, 1% 낮춘 처리와 원수로 재배한 처리였다. 식물체 내의 다량원소 분석을 위해 수확 후 ICP 분석을 하였으며 생체중과 엽수를 측정하였다. 실험 결과 식물체 내 칼륨함량은 대조구에 비해 2주전 처리에서 통계적으로 유의하게 낮았다. 생체중과 엽수는 대조구와 처리구에서 유의적인 차이를 보이지 않았으나 처리구간의 유의적인 차이는 있었다. 신장환자들 의 채소섭취량을 고려했을 때, 저칼륨 상추 생산을 위한 적당한 칼륨농도 조성은 수확 2주전 1%와 5%로 낮춘 처리였다. 본 연구를 통해 양액 내 칼륨함량과 처리시리를 조절하여 신장환자를 위한 저칼륨 상추를 개발할 수 있었다.

The aim of this work was to evaluate the dielectric properties of impregnated and activated palm kernel shells (PKSs) samples using two activating agents, potassium carbonate (K2CO3) and sodium hydroxide (NaOH), at three impregnation ratios. The materials were characterized by moisture content, carbon content, ash content, thermal profile and functional groups. The dielectric properties were examined using an open-ended coaxial probe method at various microwave frequencies (1–6 GHz) and temperatures (25, 35, and 45°C). The results show that the dielectric properties varied with frequency, temperature, moisture content, carbon content and mass ratio of the ionic solids. PKSK1.75 (PKS impregnated with K2CO3 at a mass ratio of 1.75) and PKSN1.5 (PKS impregnated with NaOH at a mass ratio of 1.5) exhibited a high loss tangent (tan δ) indicating the effectiveness of these materials to be heated by microwaves. K2CO3 and NaOH can act as a microwave absorber to enhance the efficiency of microwave heating for low loss PKSs. Materials with a high moisture content exhibit a high loss tangent but low penetration depth. The interplay of multiple operating frequencies is suggested to promote better microwave heating by considering the changes in the materials characteristics.

Although stem cells are used as important cell therapies in regenerative medicine, the electrophysiological problems that arise in the expansion of cells have not been known much. This study was conducted to investigate the functional expression of inward rectifying K+ current (IKir) using a patch-clamp technique, and the change in the resting membrane potential and the membrane capacitance were investigated in mesenchymal stem cells derived from human umbilical vein (hUC-MSC). The IKir plays an important role in regulating the resting membrane potential in many cells and is known to contribute to the maintenance of intracellular K+ concentration. In this study, electrophysiologically recorded current exhibited typical IKir characteristics. The current shifted along the K+ equilibrium potential (Ek) with the extracellular K+ concentration change. In addition, IKir was blocked by the divalent Ba2+ in a dose-dependent manner. The frequency of functional expression of IKir changed with number of passages (P2: 5.3% vs P8: 77.8% vs P12: 34.5%). There was no significant change in the resting membrane potential of hUC-MSC (P2: -21.0 mV, P8: -20.1 mV and P12: -21.9 mV). However, the capacitance of the cell membrane was significantly changed after P9 (P2: 8.9 pF vs P9: 16.9 pF) compared to P2. All the results suggest that changes in electrophysiological distribution of IKir as the passages increase may cause changes in K+ permeability even in cell proliferation and differentiation, suggesting a possible physiological role in maintaining cell homeostasis and resting membrane potential (RMP).

We synthesized potassium hexatitanate, (K2Ti6O13, PT6), with a non-fibrous shape, by acid leaching and subsequent thermal treatment of potassium tetratitanate (K2Ti4O9, PT4), with layered crystal structure. By controlling nucleation and growth of PT4 crystals, we obtained splinter-type crystals of PT6 with increased width and reduced thickness. The optimal holding temperature for the layered PT4 was found to be ~920 oC. The length and width of the PT4 crystals were increased when the nucleation and growth time were increased. After a proton exchange reaction using aqueous 0.3 M HCl solution, and subsequent heat treatment at 850 oC, the PT4 crystal transformed into splinter-type PT6 crystals. The frictional characteristics of the friction materials show that as the particle size of PT6 increases, the coefficient of friction (COF) and wear amounts of both the friction materials and counter disc increase.

파프리카는 내수 뿐 아니라 수출 수요 증가로 시설재배 작물 중 가장 고소득 작물중의 하나로 부상하였다. 그런데 파프리카가 일반적으로 수경재배로 생산되고 있기 때문에 토양재배에서는 시비기준이 없어 시험을 수행 하였다. 질소와 칼륨의 관비기준을 설정하기 위하여 피망의 검정시비량을 기준으로 0.5. 1.0, 1.5, 2.0배로 시험 처리구를 두었고 질소 시험은 2012년에, 칼륨 시험은 2013년에 각각 수행하였다. 질소 관비 시험에서는 0.5배 관비구에서 다른 처리에 비하여 측지 두께가 비하여 얇았으나 길이는 처리의 영향을 받지 않았다. 착과수와 수량은 1그룹 수확에서 처리에 따른 차이가 발생하지 않았으나, 2그룹 수확에서는 1.0배 이상 처리에서 시비량이 많아질수록 감소하는 경향을 나타내었으며, 0.5배 처리구에서 가장 낮았다. 전체적인 수량을 기준으로 판단했을 때 파프리카 관비재배 시 질소의 시비량은 피망검 정시비량의 1.0배가 적정하다고 판단되었다. 칼륨 관비 시험에서는 관비량이 많은 처리구일수록 측지의 길이가 길었던 것을 제외하고 처리간 뚜렷한 생육의 차이를 나타내지 않았다. 심실수, 과피두께, 당도는 처리에 따른 차이를 나타내지 않았다. 과실의 착과수와 수량은 1, 2 그룹에서는 통계적 유의차를 나타내지 않았으나 3그룹에 서는 처리간에 뚜렷한 차이가 발생하여 1.5배 관비구에서 최대가 되었다. 전체적인 수량을 기준으로 판단했을 때 토양검정을 기준으로 한 관비재배에서 칼륨시비량은 피망검정시비량의 1.5배가 적정하다고 판단된다.

To determine the contents of sodium and potassium in side dishes, 92 samples from 22 different kinds of side dishes that can be classified into 3 groups were collected in Seoul area and analysed using ICP-OES. The highest sodium content was detected in pepper doenjang muchim, while potassium content was the highest in kong jorim. When comparing the content of sodium and potassium in 3 groups, namely namul, muchim, and jorim, the sodium content of namul group was significantly different from those of jorim and muchim (p-value < 0.05). Sodium intake per serving size was the highest in parae muchim among the samples as estimated to 20.2% of WHO recommendation that is 2,000 mg/day. The amount of sodium by simultaneously intake of soybean sprouts namul, anchovy jorim and parae muchim per one serving size was estimated to 1,000 mg. The potassim/sodium ratios of spinach namul and kong jorim were 1.70 and 0.81, respectively, while that of bracken namul was very low as about 0.1. Foodborne pathogens were not detected out of 92 side dishes.

Obesity is a risk factor for various diseases, including cardiovascular disease, diabetes, renal disease, hypertension, cancer, and neural disease. Adipose tissue in animals is important for the mobilization of lipids, milk production, deposition of fat in different depots, and muscle and meat production. Understanding the genetic and physiological causes of metabolic disease is a priority in biomedical genome research. In this study, we examined several variables in mice fed a high-fat diet, including serum composition, body weight, total calorie intake, and differentially expressed genes. Body weight and blood glucose levels were not significantly different between animals fed high-fat and normal diets. However, high-fat diet groups showed reduced calorie and food intakes. Levels of sodium, ionized calcium, glucose, hematocrit, hemoglobin, pH, PCO2, PO2, TCO2+, HCO3+, base excess, and SO2 in the blood were not significantly different between mice fed high-fat and normal diets. Serum potassium concentration, however, was lower in mice a high-fat diet. Differentially expressed genes were also compared between the two groups. The purpose of this study was to discover new genes as a result of annealing control primer (ACP) PCR using 20 random primers. Five down regulated genes were identified and three of others were up-regulated by high-fat diet. Known genes were excluded from this result. In addition, the relationships among candidate genes and high-fat diet should be investigated according to potassium concentration in the blood. In conclusion, mice fed normal and high-fat diets showed no significant difference in body weight, whereas high-fat diet led to changesin blood composition and differential expression of several genes. These findings may provide a better understanding of the mechanisms underlying the association between obesity and metabolic diseases.

시설재배지에서 수용성 규산칼륨 처리가 수박의 생육, 수량, 양분흡수 및 토양특성에 미치는 영향을 조사하기 위해 수용성 규산칼륨을 무처리, 1.63mM, 3.25mM, 6.50mM의 4수준을 두어 토양관주 처리하였으며, 처리시기는 착과전 2회와 착과후 4회로 총 6회를 7일 간격으로 처리하였다. 시험후 토양화학성은 수용성 규산처리에 따라 pH, EC 유효인산, 치환성 K, Ca, Mg, NO3-N은 증가하였으며, 유기물 함량은 대조구와 비슷하였다. 수확 기 수박 생육 특성 중 경경, 생중 및 건물중은 수용성 규산칼륨 처리에서 두껍고 무거웠으며, 만장과 절수는 유의적인 차이를 나타내지 않았다. 수박 수확기 잎에 함유되어 있는 무기성분 함량은 수용성 규산칼륨 수준이 높아짐에 따라 N은 감소하고 P와 K는 증가하였으나 Ca 과 Mg는 차이가 없었다. 생육단계별 엽록소함량은 착과 전에는 수용성 규산칼륨처리에 따른 차이가 없었으나 착과후 및 수확기로 갈수록 수용성 규산칼륨 수준이 높아짐에 따라 엽색도가 높아지는 경향을 보였다. 흰가루병 발생정도는 대조구에 비하여 수용성 규산칼륨 수준이 높을수록 발생정도가 낮았다. 수박의 과중은 수용성 규산 칼륨 처리에 의해 0.1~0.5kg/개 무거워졌으며, 당도는 0.5~0.6 oBrix 정도 높아졌고, 상품수량은 대조구에 비하여 2~4% 증수되었다. 이상의 결과 시설수박 재배지에 수용성 규산칼륨 처리는 양분흡수 증가, 수박 상품수량 증가 및 흰가루병 발생 억제로 시설 수박재배에 친환경적인 방법으로 안정생산에 활용할 수 있으리라 본다.

나트륨 저감화를 위한 식생활 지도의 기초자료로 활용하고자 서울지역 다소비 음식점 메뉴를 대상으로 나트륨함량이 높은 국 및 탕류, 찌개 및 전골류, 면류 등에 대한 나트륨 및 칼륨 함량을 조사하였다. 음식점 메뉴는 생선찌개 등 25종류 144건과 김치 50건이다. 음식점 메뉴 중 김치의 나트륨 및 칼륨 평균 함량이 각각 554.9 ± 155.5 mg/100 g, 225.1 ± 69.1 mg/100 g으로 가장 높았으며, 반면 설렁탕의 나트륨 및 칼륨 평균 함량이 각각 24.2 ± 5.8 mg/100 g, 12.7 ± 3.9 mg/100 g으로 가장낮게 나타났다. 음식점 메뉴의 나트륨과 칼륨 평균 함량간의 상관관계를 분석한 결과, 상관계수가 0.782(P < 0.01)로 양의 선형관계가 있는 것으로 나타났다. 나트륨/칼륨비는 불고기가 1.17 ± 0.44로 가장 적합한 비를 나타내었고, 우동, 잔치국수, 칼국수의 나트륨/칼륨 비는 10이상으로 높게 나타나 칼륨 함량에 비해 나트륨 함량이 높음을알 수 있었다. 음식군 분류별 나트륨 및 칼륨 평균 함량은 통계적으로 유의한 차이가 있는 것으로 나타났다(p < 0.001). 음식군별 나트륨 평균 함량은 김치류가 554.9 ± 155.5 mg/100 g으로 가장 높았고, 찌개 및 전골류, 국 및 탕류, 볶음류, 면류 순이었다. 칼륨 평균 함량도 김치류가 225.1 ± 69.1 mg/100 g으로 가장 높았고 볶음류, 찌개 및 전골류, 국 및 탕류, 면류 순이었다. 음식군 분류별 나트륨/칼륨 비도 통계적으로 유의한 차이가 있는 것으로 나타났다(p < 0.001). 볶음류가 1.18 ± 0.44로 나트륨/칼륨 비가 1에 가장 근접하였고 김치류, 찌개 및 전골류, 국 및 탕류, 면류 순이었다. 적절한 나트륨/칼륨 비의 유지가 건강에 도움이 되므로 나트륨 섭취를 줄이고 칼륨 섭취를 증가시킬 수 있는 방법에 대한 홍보와 함께 효과적인 식단 및 식생활교육의 개발과 보급이 필요할 것으로 판단된다.

Bladder cancer is a common cancer in smoking men and may correlate with mechanosensitive potassium channels because the urinary bladder is a stretch sensing organ. Two-pore K+ channels (K2P), such as TASK3 and TREK1, have recently been shown to play a critical role in both cell apoptosis and tumorigenesis. Of the channels, TREK1 can be activated by many physiological stimuli, including polyunsaturated fatty acids, and intracellular pH, hypoxia, and neurotransmitters. Here we attempted to determine whether TREK1 is functionally expressed in bladder cancer 253J cells. K2P channels, including TREK1, TREK2, TASK1, TASK3, and TWIK1, were quantified in cultured human bladder cancer 253J cells using real time quantitative RT-PCR (qRT-PCR) analysis. Among them, TREK1-like channel was recorded at a single channel level using the patch-clamp technique. The TREKl-like channel, with single-channel conductance of ~90 pS at −80 mV, was recorded in symmetrical 150 mM KCl using an excised inside-out patch configuration. The current- voltage relationships were linear and were insensitive to tetraethylammonium. The channel was activated by membrane stretch, free fatty acids, and intracellular acidosis. These results with electrophysiological properties resemble to those of K2P channel, for instance, TREK1. Therefore, we conclude that TREK1 channel is functionally present in bladder cancer 253J cells.

This study was conducted to determine the effects of partial replacement (40.0%) of sodium chloride by potassium chloride, potassium lactate and calcium ascorbate on quality characteristics of cooked pork ham during cold storage. The cooked pork hams with partial replacement of sodium chloride by potassium chloride and potassium lactate had lower lightness (L*) and higher bitterness than others (p <0.05). However, redness (a*), yellowness (b*) and overall acceptability of sensory properties were not different among the treatments (p >0.05). The partial replacement of sodium chloride by all substitutes leads to increase tenderness (p <0.05). There are no problems in microbiological stability and lipid oxidation of cooked pork hams with 40% replacement of sodium chloride by potassium chloride, potassium lactate and calcium ascorbate during cold storage. Therefore, it is possible to use potassium chloride, potassium lactate and calcium ascorbate as partial substitutes of sodium chloride in cooked pork ham.

Various voltage-gated K+ currents were recently described in dorsal root ganglion (DRG) neurons. However, the characterization and diversity of voltage-gated K+ currents have not been well studied in trigeminal root ganglion (TRG) neurons, which are similar to the DRG neurons in terms of physiological roles and anatomy. This study was aimed to investigate the characteristics and diversity of voltage-gated K+ currents in acutely isolated TRG neurons of rat using whole cell patch clamp techniques. The first type (type I) had a rapid, transient outward current (IA) with the largest current size having a slow inactivation rate and a sustained delayed rectifier outward current (IK) that was small in size having a fast inactivation rate. The IA currents of this type were mostly blocked by TEA and 4-AP, K channel blockers whereas the IK current was inhibited by TEA but not by 4-AP. The second type had a large IA current with a slow inactivation rate and a medium size-sustained delayed IK current with a slow inactivation rate. In this second type (type II), the sensitivities of the IA or IK current by TEA and 4-AP were similar to those of the type I. The third type (type III) had a medium sized IA current with a fast inactivation rate and a large sustained IK current with the slow inactivation rate. In type III current, TEA decreased both IA and IK but 4-AP only blocked IA current. The fourth type (type IV) had a smallest IA with a fast inactivation rate and a large IK current with a slow inactivation rate. TEA or 4-AP similarly decreased the IA but the IK was only blocked by 4-AP. These findings suggest that at least four different voltage-gated K+ currents in biophysical and pharmacological properties exist in the TRG neurons of rats.

Ammonium dinitramide (AND) is one of the most promising oxidizers in propellants without chlorinated pollution to the atmosphere in these days. Potassium sulfamate (PS) is a key substance in ADN synthesis as forming nitrates such as -N(NO2)2. In this paper, potassium sulfamate as a starting material for ADN synthesis was prepared in a lab scale through crystallization with ethanol solvent, and observed the effects on the yield and purity of KDN. The prepared potassium sulfamates were analyzed using FE-SEM, XRD, BET and TGA-DSC. The lab-made PS, which was ground to 20μm showed more beneficial than a commercial product achieving high yield and purity of the synthesized KDN. It would be associated closely with crystallinity, porosity and pore size of prepared PS.

The aims of the present study were to estimate the possibility for toxicity test and compare acute toxicity of potassium dichromate in the larva stage of Neocaridina denticulata, Daphnia magna and the juvenile stage of Oryzias latipes. N. denticulate, a freshwater shrimp lives in Korea, is an indigenous species and considered to be useful for toxicity test. D. magna and O. latipes were recommended as a test species for the OECD test guideline. The 96 h-LC50 potassium dichromate value was 0.62 mg L-1 for the larva stage of N. denticulata and 168.44 mg L-1 for the juvenile stage of O. latipes. The 48 h-EC50 value was 1.27 mg L-1 for the D. magna. The study was confirmed higher sensitivity of the larva stage of N. denticulata to potassium dichromate compared to the D. magna and the juvenile stage of O. latipes.

본 연구는 칼륨의 독성에 따른 배추의 생육과 생리적 특성 그리고 형태적 변화를 관찰하기 위하여 수행하였다. 100mM의 칼륨 농도 처리구까지 전체적인 생육이 증가한 반면, 600mM 처리구에서 생육이 가장 저조하였다. 칼륨 처리 농도가 높을수록 N, P, K, 함량은 증가하였지만 Ca, Mg, Na 함량은 감소하는 경향을 보였으며 미량원소, Fe, Mn, Zn의 경우 100mM의 처리구에서 가장 높은 함량을 나타내었다. 생체중당 Chl a, b와 carotenoid 함량은 600mM에서 가장 많이 증가하였으나 증가한 엽록소 함량에 비해 광합성효율(Fv/Fm)은 처리구간에 차이가 없었고 CO2 동화율은 오히려 감소하였다. 이는 칼륨 과다에 의한 삼투스트레스의 결과로 기공의 퇴화와 CO2 동화능력과 밀접한 관계가 있는 것을 형태학적 관찰로 확인되었다. Total free amino acid의 경우 100mM 처리구까지 칼륨 처리 농도가 증가함에 따라 증가한 반면 600mM에서 급격히 감소하였다. 따라서 본 실험에서의 배추는100mM의 칼륨 농도까지는 긍정적인 효과가 있는 것으로 판단되었다.

Petroleum pitch-based activated carbons (ACs) were obtained in this work from a combination of pretreatment with different amounts of potassium permanganate (KMnO4) and chemical activation with potassium hydroxide. The surface characteristics of the pitch after the KMnO4 pretreatment were characterized by means of Fourier transform infrared spectroscopy (FT-IR). The structural characteristics of the pitch after the KMnO4 pretreatment were determined by means of X-ray diffraction. The influence of the KMnO4 treatment on the textural properties of the petroleum pitch-based ACs was investigated by means of N2/77K adsorption isotherms. The investigation also involved the use of the Brunauer-Emmett-Teller equation and the Dubinin-Radushkevich method. The FT-IR results show that the pretreatment promotes the formation of surface oxygen functionalities and leads to an increase of the interplanar distance (d002) of the functional groups induced between carbon layers. Moreover, the specific surface area of the pitch-based ACs increases in proportion to the amount of KMnO4 pretreatment and reaches its highest value of 2334 m2/g with 2 g of KMnO4 because the surface oxygen groups of the pitch act as an active site during chemical activation.

The analysis of reaction kinetics provided that the reaction order was the 1st of triglyceride and the rate constant was 0.067 min-1. The transesterification of camelina oil using 0.6 wt% mixed catalyst which consists of 40 v/v% of potassium hydroxide (1 wt%) and 60 v/v% of tetra methyl ammonium hydroxide (0.8 wt%), was carried out at 65℃ on the tubular reactor packed with static mixer. The conversion was shown to be 95.5% at the 6:1 molar ratio of methanol to oil, flow rate of feed of 3.0 mL/min and 24 of element of static mixer. The volume of washing water emitted by 0.6 wt% mixed catalyst was the half of the volume emitted by 1 wt% potassium hydroxide.

Sodium-potassium-chloride co-transporter (NKCC) is a membrane bound channel protein that plays a prominent role in a variety of epithelial absorptive, secretory processes and a direct role in cell volume regulation, in which NKCC transports sodium, potassium, and chloride ions across the cell membrane. It has been known that prostaglandin E2 (PGE2) induces an acute cell lysis of specific hemocyte type, oenocytoid, to release prophenoloxidase into the plasma and ouabain (a specific sodium pump inhibitor) inhibits the oenocytoid cell lysis resulting in preventing phenoloxidase activation. However, it is not clear how the intracellular signaling pathway leads to oenocytoid cell lysis in response to PGE2. This study was designed to analyze functional role of NKCC in the cell lysis to release prophenoloxidase. A gene structure of NKCC was derived from cDNA library of Spodoptera exigua hemocyte, NKCC was expressed in all developmental stages and tissues. A real time quantitative RT-PCR showed that bacterial challenge significantly induced its expression. Specific inhibitors of NKCC, bumetanide and chlorothiazide, clearly prevented the cell lysis in a dose dependent manner. When RNA interference using double stranded RNA (dsRNA) specific to NKCC suppressed its expression, the oenocytoid lysis and PO activation was significantly inhibited in response to PGE2. It also reduced nodule formation to bacterial challenge. These results indicate that NKCC is associated with oenocytoid cell lysis probably by increasing cell volume through inward transport of ions in response to PGE2.