• Proceedings of the Korean Society of Applied Pharmacology
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• 1996.04a
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• pp.219-219
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• 1996

Mucin release from hamster tracheal surface epithelial(HTSE) cells can be stimulated by extracellular ATP via activation of P$_2$ purinoceptors located on the cell surface which appears to be coupled to phospholipase C via G proteins. However, our preliminary data indicate that the ATP-induced mucin release involves, in part, activation of PKC, but not an increase in the intracellular Ca++ level, suggesting the presence of another pathway which is separate from the PLC-PKC pathway, In this study, we intended to confirm the previous observation and subsequently identify an additional mechanism. Confluent HTSE cells were metabolically labeled with either $^3$H-glucosamine or $^3$H-arachidonic acid(AA), and release of either $^3$H-mucin or $^3$H-AA was quantified following various treatments. $^3$H-mucin was assayed using the sepharose CL-4B gel-filtration method, whereas $^3$H-AA liberation was measured by counting $^3$H-radioactivity in the chase medium. We found that: (1)Desensitization of PKC by pretreatment with PMA completely abolished the mucin releasing effect of PMA but partially inhibited the ATP-induced mucin release; (2) ATP increases release of $^3$H-AA in a dose-dependent fashion; (3) mepacrine, an inhibitor of PLA$_2$, attenuates ATP-induced mucin release in a dose-dependent fashion. These results confirm our previous notion that the PLC-PKC pathway is responsible, in part, for ATP-induced mucin release. Furthermore, activation of PLA$_2$ appears to be an additional pathway which is involved in ATP-induced mucin release.

• The Korean Journal of Pain
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• v.25 no.4
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• pp.221-227
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• 2012

Background: It has been reported that curcumin, the main active compound of Curcuma longa, also known as turmeric, exhibits antinociceptive properties. The aim of this study was to examine the participation of ATP-sensitive potassium channels ($K_{ATP}$ channels) and, in particular, that of the L-arginine-nitric oxide-cyclic GMP-$K_{ATP}$ channel pathway, in the antinociceptive effect of curcumin. Methods: Pain was induced by the intraplantar injection of 1% formalin in the right hind paw of Wistar rats. Formalin-induced flinching behavior was interpreted as an expression of nociception. The antinociceptive effect of oral curcumin was explored in the presence and absence of local pretreatment with L-NAME, an inhibitor of nitric oxide synthase, ODQ, an inhibitor of soluble guanylyl cyclase, and glibenclamide, a blocker of $K_{ATP}$ channels. Results: Oral curcumin produced a dose-dependent antinociceptive effect in the 1% formalin test. Curcumin-induced antinociception was not altered by local L-NAME or ODQ, but was significantly impaired by glibenclamide. Conclusions: Our results confirm that curcumin is an effective antinociceptive agent. Curcumin-induced antinociception appears to involve the participation of $K_{ATP}$ channels at the peripheral level, as local injection of glibenclamide prevented its effect. Activation of $K_{ATP}$ channels, however, does not occur by activation of the L-arginine-nitric oxide-cGMP-$K_{ATP}$ channel pathway.

• Journal of Plant Biology
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• v.23 no.1
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• pp.17-25
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• 1980

Kidneybean(Phaseolus vlgaris L.) and buckwheat(Fagopyrum esculentum M$\"{O}$nch) seedlings cultured with Hoagland solution to the height of 7 to 10cm in the earthern pot containing sand were used for experimental plants. One group of the plants was irrigated with Hoagland solution composed of various Al concentrations of 0 to 1,000 ppm containing 50ppm Ca, and the other group was irrigated with Hoagland solution composed of various Ca concentrations of 0 to 1,000ppm containing 100ppm Al for a month during June and July. By Al-surplus over 100ppm, the margins of backwheat leaves were curied down and turned into yellow-brown necrosis simialr to Ca-deficiency, and the old kidney bean leaves showed marginal and veinal chlorosis in addition to the early shedding of leaves. With Al-surplus of 100ppm the content of chlorophyll a and b in both plants was decreased by 30~40%. The ratio 3/1 of chlorophyll a/b was not altered by Al-surplus and Ca-deficienty at an early stage, but it was affected markedly at a final stage of growth. Leaf respiration with 100ppm Al containing 50pm Ca was slightly affected in buckwheat, but decreased by 20% in kidneybean. With Al-surplus of 100ppm the ATP content was decreased by 32% in the kidneybean leaves and by 80% in buckwheat leaves, whereas with Ca-deficiency it was decreased by 72% in kidneybean and by 90% in buckwheat. The rhythm of ATP level showed self-relience without being affected by light or temperature under the green house condition although by Al-s rplus and Ca-deficiency the ATP level of the rhythm was lower than that of control.trol.

• Proceedings of the KSR Conference
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• 2011.05a
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• pp.910-917
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• 2011

CBTC(Communication Based Train Control) car-borne equipment, a part of the communication based train control system, mainly consists of automatic train protection(ATP) functions, automatic train operation(ATO) functions as well as the interface functions with other equipment including CBTC wayside equipment and train control management system etc. The CBTC car-borne software implementing ATP/ATO functions is a real-time embedded software requiring a high level of safety and reliability. To satisfy the requirements of the CBTC car-borne software, the model-based design techniques are applied with SCADE(Safety-Critical Application Development Environment) to the development of the CBTC car-borne software. In this paper, we illustrate the process modeling the car-borne ATP/ATO functions satisfying system requirement specification with system requirement management, modeling and document generation tools etc. supported by SCADE. In addition, the developed models corresponding to the ATP/ATO functions are applied to the train with CBTC car-borne equipment through its corresponding EN-50128 standards-compliant C code generated by the code generator. It is shown from the test result that the ATP/ATO models developed by SCADE work well while the trains are running in driverless operation mode.

• Molecules and Cells
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• v.22 no.2
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• pp.198-202
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• 2006

The $P2X_7$ receptor, an ATP-gated cation channel, induces cell death in immune cells and is involved in neurodegenerative diseases. Although the receptor plays various roles in these diseases, the cellular mechanisms involved are poorly understood and antagonists are limited. Here, the development of a cell-based assay for human $P2X_7$ receptor is reported. We established permanent lines of HEK 293 cells expressing a high level of $hP2X_7$ receptor. Functional activity of the $hP2X_7$ receptor was confirmed by whole-cell patch recording of ATP-induced ion currents. Prolonged exposure to ATP resulted in death of the $hP2X_7$-expressing HEK 293 cells and this cell death could be quantified. Two known $P2X_7$ antagonists, PPADS and KN-62, blocked ATP-induced death in a concentration-dependent manner. Thus, this assay can be used to screen for new antagonists of $hP2X_7$ receptors.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.5
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• pp.179-188
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• 2021

The purpose of this study is to examine the level of aggressive tax planning (ATP) among companies listed in the Access, Certainty, Efficiency (ACE) Market of Bursa Malaysia. On top of that, this study also investigates the relationship between company characteristics, ethnicity, and ATP. This study uses a balanced pooled sample of 105 firm years-observations for the period from 2014 to 2018. These samples were selected to provide new insight into this market and to explore the attitude of small firms toward ATP in Malaysia. The data was retrieved from DataStream and the downloaded annual reports. The finding shows that profitability and financial distress have a significant relationship with ATP. Other variables including size, capital intensity, inventory intensity, leverage, and ethnicity, were not determinants of ATP. The result in this study may assist the reader in understanding the nature of companies in the ACE market, particularly on its behavior toward tax planning. A strict requirement is needed to be adopted in the sample selection process, thus limiting the sample size. Further, since the previous study focused on large companies, the discussion of this paper will provide new insight into the nature of tax planning within the small- and medium-sized companies in Malaysia.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.8
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• pp.29-36
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• 2021

This study aims to estimate and calculate the ability to pay (ATP) and the willingness to pay (WTP) of households for wastewater management services (IPAL), the relationship between ATP and WTP, and factors that affect WTP. The location of IPAL construction is in the area of Lampung Province, Indonesia. There are 158 selected households for this study. The study employs a purposive sampling method in which the characteristics of households are classified into 3 categories - former households, newcomer households who had come to this area and have no experience of using water supply services, and newcomer households who have experience of using water supply services such as PDAM. The results of this study are, ATP and WTP values were not always in the same direction. The highest ATP was for newcomer households with experience of water supply services but the WTP was the lowest, on the contrary, the lowest ATP was for former households, but the WTP was the highest. Furthermore, experience and cognitive reference are positively correlated with WTP. Service quality perception, education/knowledge of respondents about environmental conservation, and level of income correlate with WTP.

• Korean Journal of Veterinary Research
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• v.29 no.3
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• pp.393-405
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• 1989

This study was carried out to treatment test for bovine mastitis by the determination of adenosine triphosphate (ATP) based on firefly bioluminescence. The results obtained are followed; 1. In the susceptibility test, cephalothin which looks the most effective were sensitive to Staphylococcus sp. (72.3%), Micrococcus sp. (84.2%), Streptococcus sp. (72.7%) and Gram positive bacilli (72.7%), Gram negative bacilli were sensitive to gentamicin (92.3%) and Yeast-like-fungi was the most sensitive to clotrimazole, and nystatin in order. 2. When the number of bacteria, such as Staphylococcus aureus, Candida tropicalis isolated from the mastitis milk were counted by conventional agar plating technique, and compared with the concentration of bacterial ATP, it gave a good linear relationship. The content of ATP per Staphylococcus aureus, cell was 3.1fM and Candida tropicalis showed the high level of A TP (90fM). 3. The ATP assay was applied to the determination of minimal inhibitory concentration (MIC) of various antibiotics. When Staphylococcus aureus was incubated in the presence of different concentration of tetracycline, erythromycin, kanamycin and streptomycin sulfate and the growth was monitored by the conventional agar plating technique and ATP assay, both methods shown the same results that they were 1mcg/ml, 2mcg/ml, 6.25mcg/ml and 8mcg/ml, respectively. 4. For the determination of susceptibility of sensitive and resistant Staphylococcus au reus isolated for the milk with mastitis to tetracycline, erythromycin kanamycin and streptomycin sulfate, the minimum time required for the test was determined by the assay of ATP every 30 minutes during incubation of 3 hours at $37^{\circ}C$. ATP concentration time curve calculated on both resistant and sensitive strains incubated 3 hours as the optimum time for the determination of susceptibilities of various antibiotics exemed. The ATP concentration of each test broth (antibiotic containing), expressed as a percentage of its own control brith (antibioticfree) indicated values of 30% to be indicative of each antibiotic sensitivity. Single time point ATP assay carried out on the various sensitive and resistant of Staphylococcus aureus to antibiotics examined after 3 hours at $37^{\circ}C$ correlated exactly with disc diffusion and MIC. 5. In the cure of intramammary treatment of bovine mastitis in lactating quarters, the cure rate of Staphylococcal mastitis showed to cephalexin (80%), cloxacillin and gentamicin (70%), ampicillin and oxytetracycline (60%), and Streptococcal mastitis showed to cephalexin (85%), penicillin (80%), cloxacillin and oxytetracycline (75%), and ampicillin (70%), but intramammary antimycotic drug (clotrimazol) were only a little effect about fungal mastitis.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.10
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• pp.1353-1359
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• 2001

The present study was undertaken to assess the influence of dimethyl-sulfoxide plus sucrose solution as a cryoprotectant on the adenosine triphosphate (ATP) content, the ultrastructure and the embryonic development of bovine oocytes matured in vitro. We measured the amount of ATP in cumulus cells enclosed oocytes (CO) or denuded oocytes (DO) equilibrated with or removed from the cryoprotectant (1.5 M DMSO + 0.25 M sucrose + 20% fetal bovine serum in physiological saline). As a result, the ATP contents in both CO and DO, equilibrated with the cryoprotectant, were significantly lower (p<0.05) than that of the each control group. However, ATP content of DO was recovered to the level of the control group ailer removal of the cryoprotectant, but failed to restore for CO. In the observation of the ultrastructure by a transmission electron microscope, all of the mitochondria in the ooplasm of CO and DO equilibrated with the cryoprotectant were swollen with peripherally located cristae following decreased electron density. However, a large proportion of these swollen mitochondria were restored to the normal shape which can be observed usually in the control group after removal from the cryoprotectant. To the contrary, the morphology of many mitochondria of the cumulus cells in CO were not recovered to that of the control group after removal of the cryoprotectant. CO with removed cryoprotectant had significantly lower embryonic development up to the blastocysts stage (p<0.05) after in vitro fertilization compared with that in the control group. These results suggest that the addition and removal of a cryoprotectant has a negative effect for the ATP content of cumulus enclosed oocytes. One of the factor(s) causing the lower embryonic development after removal of cryoprotectant, may be associated with ATP metabolism.

• The Korean Journal of Physiology and Pharmacology
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• v.5 no.5
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• pp.433-441
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• 2001

The ATP-sensitive potassium $(K_{ATP})$) channel is a member of inward rectifier potassium channel (Kir) that is inhibited by intracellular ATP and functions in close relation to sulfonylurea receptors (SUR). Although the molecular mechanism and physiological function of $K_{ATP}$ channels are well understood, the expression pattern during development or treatment with the channel modulators such as glybenclamide is little known. In this work, we determined mRNA levels of a $K_{ATP}$ channel (Kir6.2) and a sulfonylurea receptor (SUR2) in rat tissues by RNase protection assay. Levels of Kir6.2 and SUR2 mRNA in the rat brain and skeletal muscle were higher in adult $(90{\sim}120\;days)$ than in neonate $(2{\sim}8\;days),$ whereas those in the heart were not much different between neonate $(2{\sim}8\;days)$ and adult $(90{\sim}120\;days).$ In addition, none of $K_{ATP}$ channel modulators (opener, pinacidil and nicorandil; blocker, glybenclamide) affected the Kir6.2 mRNA levels in the heart, brain and skeletal muscle. The results indicate that the expression of Kir and SUR genes can vary age-dependently, but the expression of Kir is not dependent on the long-term treatment of channel modulators. The effect of the channel modulators on mRNA level of SUR is remained to be studied further.