• Korean journal of applied entomology
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• v.34 no.3
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• pp.181-190
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• 1995

Malate dehydrogenase in the mosquito ovary after a blood meal, Aedes aegypti, was purified and characterized. MDH purification steps involved DEAE-Sepharose, S-Sepharose and Cibacron blue affinity chromatography. The purified MDH was 70,000 daltons in molecular weight and was a homodimer consisting of tow identical subunits. Optimal activity of purified MDH was obtained pH 9.0-9.2 in malate-oxaloacetate reaction and pH 9.8-10.2, in oxaloactate-malate reaction. With obtained pH 9.0-92 in malate-oxaloacetate reaction and pH 9.8-10.2, in oxaloactate-malate reaction. With malate as substrate, purified mitochondrial MDH (1.28$\times$${10}^{-4}$ M) had lower Km value than cytoplasmic MDH (8.92x${10}^{-3}$ M). MDH activity was inhibited by citrate, $\alpha$-ketoglutarate, and ATP. Inhibition of MDH activity by ATP and citrate was less in malate-oxaloacetate reaction and in oxaloacetate-malate reaction. MDH activity was completely inhibited by ATP in oxaloacetate-malate reaction and not inhibited by citrate in malate-oxaloacetate reaction. Temporal activity change of MDH is similar to that of isocitrate dehydrogenase in the ovary after blood feeding; their activities in the ovary began to rise at 18 hours after a blood meal, and reached at the maximal level at 48 hours.

• Korean Journal of Veterinary Research
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• v.35 no.2
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• pp.245-254
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• 1995

The density of ATP-sensitive potassium($K_{APT}$) channels, that open as intracellular ATP concentration falls below a critical level, is very high in skeletal muscle surface membrane and those high density may imply that $K_{ATP}$ channels have very important physiological roles. To elucidate a role of $K_{ATP}$ in relation to fatigue, the modulating effects of potassium channel openers and blockers on the fatigue velocity(FV) of mouse extensor hallucis longus muscle(EHL) were investigated in vitro. Twitch contraction was induced by an electrical field stimulation (EFS: 24-48V, 20ms, 0.2-4Hz) and resulting contraction force was isometrically recorded. The twitch forces were gradually decreased to 25% of initial contraction force(ICF) in $37.52{\pm}1.55sec$($mean{\pm}s.e.m.$, n=135), indicating the fatigue phenomena. The mean velocity for development of the fatigue was measured during the period that twitch force decreased to half($FV_{0/0.5}$) and during the period from half to 25%($FV_{0.5/0.25}$) of ICF. The fatigue was induced once every one hour and the tissue response was stable for up to 4 hours. In control condition, ICF was $5.8{\pm}0.12g$ (n=144) and decreased to 50% of ICF with the mean fatigue velocity of $0.182{\pm}0.006g/sec$($FV_{0/0.5}$, n=135) and from 50% to 25% of ICF with $0.084{\pm}0.004g/sec$($FV_{0.5/0.25}$, n=135). Cromakalim($50{\mu}M$) significantly increased $FV_{0.5/0.25}$(n=4). Glibenclamide($IC_{50}>50{\mu}M$), $Ba^{2+}$($IC_{50}=10{\mu}M$), 4-aminopyridine($FV_{0/0.5}$, $IC_{50}=0.5mM$; $FV_{0.5/0.25}$, $IC_{50}=2mM$) decreased both $FV_{0/0.5}$ and $FV_{0.5/0.25}$ concentration-dependently up to 75%. $TEA^+$(30mM), E-4031($10{\mu}M$), tolbutamide(1mM) decreased $FV_{0.5/0.25}$, but apamin(300nM) and $TEA^+$(10mM) showed no significant effects. Our results suggest that activation of the $K_{ATP}$ channels may be major cause of $K^+$ outflux during development of the fatigue and the isolated EHL muscle could be an useful experimental preparation in studying the fatigue phenomena in skeletal muscle. In addition, the possibility of activation of delayed rectifier during the fatigue development remains to be studied further.

• Applied Biological Chemistry
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• v.20 no.1
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• pp.33-42
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• 1977

Asparagine biosynthesis by soybean sprouts grown under the dark conditions has been demonstrated. The amount of free asparagine synthesized in ten day-old soybean sprouts increases to 22.7% on the dry weight base. The effects of nitrogen compounds such as $NH_4Cl,\;(NH_4)_2SO_4$ and urea on asparagine synthesis during the sprouting were examined and the results showed that urea was more effective than other two compounds. Glutamine-dependent asparagine synthetase was partially purified (8.6 folds) through ammonium sulfate fractionation, followed by Sephadex G-150 gel filtration. The enzyme was very labile and required protection by thiol groups or high level of glycerol. The mixture of ATP and $Mg^{++}$ ion also stabilized the enzyme activity. The enzyme utilized glutamine more effectively than ${NH_4}^+$ as an amide donor for the formation of asparagine. The enzyme required L-aspartate (Km=3.1 mM), L-glutamine, ATP and $Mg^{++}$. It showed pH optimum of 7.5 and catalyzed the formation of ${\beta}-aspartyl$ hydroxamate in the presence of L-aspartate, ATP, $Mg^{++}$ and $NH_2OH$ in the reaction mixture.

• Journal of Microbiology and Biotechnology
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• v.27 no.12
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• pp.2173-2179
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• 2017

The intracytoplasmic membrane of Rhodobacter sphaeroides readily vesiculates when cells are lysed. The resulting chromatophore membrane vesicle (CMV) contains the photosynthetic machineries to synthesize ATP by ATPase. The light-dependent ATPase activity of CMV was lowered in the presence of $O_2$, but the activity increased to the level observed under anaerobic condition when the reaction mixture was supplemented with ascorbic acid (${\geq}0.5mM$). Cell lysis in the presence of biotinyl cap phospholipid (bcp) resulted in the incorporation of bcp into the membrane to form biotinylated CMV (bCMV), which binds to streptavidin resin at a ratio of approximately $24{\mu}g$ bacteriochlorophyll a/ml resin. The ATPase activity of CMV was not affected by biotinylation, but approximately 30% of the activity was lost by immobilization to resin. Interestingly, the remaining 70% of ATPase activity stayed constant during 7-day storage at $4^{\circ}C$. On the contrary, the ATPase activity of bCMV without immobilization gradually decreased to approximately 40% of the initial level in the same comparison. Thus, the ATPase activity of CMV is sustainable after immobilization, and the immobilized bCMV can be used repeatedly as an ATP generator.

• Toxicological Research
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• v.23 no.1
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• pp.1-9
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• 2007

Transporters are membrane proteins that mediate the transfer of substrate across the cellular membrane. In this overview, the characteristics and the toxicological relevance were discussed for various types of transporters. For drug transporters, the overview focused on ATP-binding cassette transporters and solute carrier family 21A/22A member transporters. Except for OCTN transporters and OATP transporters, drug transporters tend to have broad substrate specificity, suggesting drug-drug interaction at the level of transport processes (e.g., interaction between methotrexate and non-steroidal anti-inflammatory agents) is likely. For metal transporters, transporters for zinc, copper and multiple metals were discussed in this overview. These metal transporters have comparatively narrow substrate specificity, except for multiple metal transporters, suggesting that inter-substrate interaction at the level of transport is less likely. In contrast, the expressions of the transporters are often regulated by their substrates, suggesting cellular adaptation mechanism exists for these transporters. The drug-drug interactions in drug transporters and the cellular adaptation mechanisms for metal transporters are likely to lead to alterations in pharmacokinetics and cellular metal homeostasis, which may be linked to the development of toxicity. Therefore, the transporter-mediated alterations may have toxicological relevance.

• BMB Reports
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• v.28 no.1
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• pp.79-82
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• 1995

Exposure of spleen lymphocytes to 2-chloroethylethyl sulfide (CEES) leads to a reduction of the intracellular ATP level, followed by a decrease in cell viability. Addition of nicotinamide, an inhibitor of poly(ADP-ribose) polymerase (PADPRP), restores both ATP level and viability, indicating that an activation of PADPRP is responsible for the cytotoxicity of CEES. The involvement of a $Ca^{2+}$-mediated process in cytotoxicity is suggested. Verapamil, EGTA, trifluoperazine, and butacaine exhibit a partial protection (20 to 58%) against the cytotoxicity of CEES. Investigation of the causative role of proteolytic degradation in cell death indicate that pepstatin and leupeptin exert a substantial protective effect (60 to 70%), suggesting the involvement of lysosomal destabilization in CEES-induced cytotoxicity. Also, lysosomotropic agents markedly decrease the cytotoxicity. Lysosomal labilization may be a mechanism for the cytotoxicity of CEES.

• Journal of the Korea Safety Management & Science
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• v.3 no.4
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• pp.181-191
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• 2001

Integrated Supply Chain Management is a important subject for all enterprise activities as include logistics/sales, transfer and storage, manufacturing, purchasing of materials. A recent customer wants to receive high level service of all parts as Qualify, Delivery, Cost and Product. Therefore, Enterprise effort to supply for customers needs use some techniques like Data Mining, POS, MIS. Inventory and Logistics cost is the highest expense of all cost from first supplier to final customer on supply routine. So, SCM's basic purpose is reduce to that cost. So that this paper explain necessary, background, concept of SCM, analyze several using methodology and function of main SCM solution, after propose to ATP model include arithmetic procedure, functions, input data for determines available due date.

• Journal of Ginseng Research
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• v.37 no.2
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• pp.176-186
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• 2013

In this study, we have investigated the effects of total saponin from Korean red ginseng (TSKRG) on thrombin-induced platelet aggregation. TSKRG dose-dependently inhibited thrombin-induced platelet aggregation with $IC_{50}$ value of about 81.1 ${\mu}g/mL$. In addition, TSKRG dose-dependently decreased thrombin-elevated the level of cytosolic-free $Ca^{2+}$ ($[Ca^{2+}]_i$), one of aggregation-inducing molecules. Of two $Ca^{2+}$-antagonistic cyclic nucleotides as aggregation-inhibiting molecules, cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP), TSKRG significantly dose-dependently elevated intracellular level of cAMP, but not cGMP. In addition, TSKRG dose-dependently inhibited thrombin-elevated adenosine triphosphate (ATP) release from platelets. These results suggest that the suppression of $[Ca^{2+}]_i$ elevation, and of ATP release by TSKRG are associated with upregulation of cAMP. TSKRG elevated the phosphorylation of vasodilator-stimulated phosphoprotein (VASP)-$Ser^{157}$, a cAMP-dependent protein kinase (A-kinase) substrate, but not the phosphorylation of VASP-$Ser^{239}$, a cGMP-dependent protein kinase substrate, in thrombin-activated platelets. We demonstrate that TSKRG involves in increase of cAMP level and subsequent elevation of VASP-$Ser^{157}$ phosphorylation through A-kinase activation to inhibit $[Ca^{2+}]_i$ mobilization and ATP release in thrombin-induced platelet aggregation. These results strongly indicate that TSKRG is a beneficial herbal substance elevating cAMP level in thrombin-platelet interaction, which may result in preventing of platelet aggregation-mediated thrombotic diseases.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.28 no.1
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• pp.23-30
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• 1995

This study was undertaken to clarify the effects of electrical stimulation on physicochemical and rheological properties of the plaice (Paralichthys olivaceus) muscle at early period after death. The plaices were electrically stimulated in seawater bath (110V/60Hz) for 15sec., 35sec., and 60sec. and killed instantly with spiking at the head. Killed samples were stored at $5^{\circ}C$, and the changes in rigor index, ATP breakdown, lactate accumulation, and breaking strength of muscle through storage were investigated. Electrical stimulation effectively accelerated rigor-mortis, lactate accumulation , and ATP breakdown. As the time of electrical stimulation was lengthened, the onset of rigor-mortis of all samples were accelerated Just after killing, and the amount of lactate was rapidly increased, But, significant differences were not observed in variance of rigor-mortis and lactate concentration. Electrically stimulated plaices showed decreasing in ATP to $4.58{\mu}mole/g$ for 15sec., $4.13{\mu}mole/g$ for 35sec., and $2.39{\mu}mole/g$ for 60sec. samples as compared with $5.5{\mu}mole/g$ of unstimulated samples. As the time of electrical stimulation was lengthened, ATP in samples were decomposed more rapidly. The rate constant of ATP breakdown were $0.244hr^{-1}$ for 15sec., $0.358hr^{-1}$ for 35sec., and $0.479hr^{-1}$ for 60sec.. The level of breaking strength in muscle of the plaice was $1050.30\pm50.23g$ immediately after killing. Values of breaking strength in samples electrically stimulated for 35sec. increased rapidly just after killing among all samples. However, the breaking strength was not increased through the whole storage time in samples stimulated for 60sec.. The value and time roaching to the maximum breaking strength for each samples stimulated electrically for 15, 35 and 60 second were $1264.43\pm35.76g$ and 2hr, $1357.68\pm22.50g$ and Ohr, and $1012.18\pm57.36g$ and Ohr. Breaking strength in all samples electrically stimulated decreased significantly (P<0.05) after reaching the maximum values.

• The Korean Journal of Nuclear Medicine Technology
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• v.22 no.2
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• pp.84-87
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• 2018

Purpose The radiopharmaceutical used in the nuclear medicine department is used only for the specific patient according to the prescription or instruction of the doctor without selling, so it is dispensed and it is distributed and used for the examination. Radiopharmaceuticals administered to patients should be managed appropriately as well as radiation safety management during dispensation. The purpose of this study is to investigate microbial contamination during dispensation of radiopharmaceuticals Materials and Methods This study distinguished between general workbench and clean workbench and performed three tests. First, microbial cultivation test of radiopharmaceutical prepared and dispensed in general workbenches and sterile workbenches were carried out five times, respectively. The second test was performed settle plate method three times before and after the use of the exhaust filter. Finally, Adenosine Triphosphate (ATP) measurement was performed in each workbench to measure bacterial counts. In addition, ATP measurement were carried out by designating locations and items that may be contaminated during dispensation. Results In the microbial culture test, no microorganisms were detected in both samples. In the settle plate method, it was detected without using of the exhaust filter in a general workbench once. In the ATP measurement test, it was measured at the level of 400 RLU or less, which is the standard value of contamination, in both workbenches surface. In additional ATP measurement test, the refrigerator handle in the distribution room was measured above the reference value of 1217 RLU, the vacuum vial shield of the Tech Generator at 435 RLU, and the syringe holder at 1357 RLU. After environmental disinfection, the results were reduced to 311 RLU, 136 RLU, and 291 RLU. Conclusion No contamination by bacteria was found in both workbenches. However, microbial contamination may occur if the use of an exhaust filter or proper hand hygiene is not achieved. Regular inspections and management for aseptic processing themselves will be necessary.