• 약학회지
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• 제43권3호
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• pp.385-390
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• 1999

Camptothecin (CPT) has been known to induce apoptosis in various cancer cell lines. To examine the intracellular apoptotic death signal initiated by CPT, we investigated the possible connection between caspase-3 activation and GSH depletion during CPT-induced apoptosis in HL-60 cells. Treatment of cells with $1{\;}{\mu}M$ CPT induced PARP cleavage accompanied by DNA fragmentation. z-VAD-fmk, a caspase-3 inhibitor, blocked the CPT-induced DNA fragmentation. Pretreatment of cells with N-acetylcysteine, a precursor of GSH biosynthesis, failed to inhibit CPT-induced PARP celavage and DNA gragmenatation. No significant changes in GSH depletion is not essential for caspase activation during CPT-induced apoptosis. We also investigated whether CPT-induced apoptosis is associated with changes of the levels of Bax and Bcl-2, two proteins involved in the control of apoptosis. Bcl-2 levels exhibited a late decrease compared with the kinetics of DNA fragmentation, whereas Bax levels increased more rapidly after CPT treatment. These results suggest that Bax plays more important role than Bcl-2 in inducing DNA fragmentation and may function upsteam of proteolytic activation of caspase-3 pathway in CPT-induced apoptosis.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• 제8권2호
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• pp.273-286
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• 1997

본 연구는 주의력결핍 ${\cdot}$ 과잉행동장애 환아에서 사건관련전위와 연속과제수행에 대한 methylphenidate(MPH)의 영향을 평가하고 사건관련전위의 변화와 연속과제수행의 변화 사이의 상관성을 알아보고자 시행되었다. 11명의 주의력결핍 ${\cdot}$ 과잉행동장애 남아에서 MPH(0.5mg/kg)의 급성효과를 알아보기위하여 사건관련전위와 연속과제수행검사를 시행하여 다음과 같은 결과를 얻었다. 약물 투여후, Fz에서 표준자극에 대한 P3 잠복기가 유의하게 감소하였고 Pz, Oz에서 표적자극에 대한 P2 진폭, 그리고 Cz에서 표적자극에 대한 P3 진폭이 유의하게 증가하였다. 또한 CPT-X 파라다임에서 탈락수와 오보수, 그리고 CPT-AX 파라다임에서 오보수가 유의하게 감소하였으며 CPT-X 파라다임의 반응의 정확도(the number of correct responses to targets, Hits)와 민감도(Perceptual sensitivity, d') 그리고 CPT-AX 파라다임의 민감도가 유의하게 증가하였다. 마지막으로 Fz에서 표적자극에 대한 P3 잠복기의 변화와 CPT-AX 파라다임의 민감도의 변화사이에는 음의 상관(p<0.05)이 있었고 Pz에서의 표적자극에 대한 P2 진폭의 변화와 CPT-X 파라다임의 민감도의 변화 사이에는 유의한 양의 상관(p<0.05)이 있었다. 결론적으로 MPH는 주의력결핍 ${\cdot}$ 과잉행동장애 아동에서 변화지향반응, 과제와 연관된 자극에 대한 반응, 정확도, 민감도를 개선시키며 비표적자극으로부터 표적자극을 구별하는 능력의 증가는 큰 기억요소를 요하는 과제에서는 자극 평가시간의 단축을 반영하며 단순과제에서는 변화지향반응의 개선을 반영하는 것으로 나타났다.

• Asian Pacific Journal of Cancer Prevention
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• 제15권6호
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• pp.2439-2445
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• 2014

Cryptotanshinone (CPT), is a quinoid diterpene isolated from the root of the Asian medicinal plant, Salvia miotiorrhiza bunge. Numerous researchers have found that it could work as a potent antitumor agent to inhibit tumor growth in vitro, buith there has been much less emphasis on its in vivo role against breast tumors. Using a mouse tumor model of MCF7 cells, we showed that CPT strongly inhibited MCF7 cell growth in vivo with polarization of immune reactions toward Th1-type responses, stimulation of naive CD4+ T cell proliferation, and also increased IFN-${\gamma}$ and perforin production of CD4+ T cells in response to tumor-activated splenocytes. Furthermore, data revealed that the cytotoxic activity of CD4+ T cells induced by CPT was markedly abrogated by concanamycin A(CMA), a perforin inhibitor, but not IFN-${\gamma}$ Ab. On the other hand, after depletion of CD4+ T cells or blocked perforin with CMA in a tumor-bearing model, CPT could not effectively suppress tumor growth, but this phenomenon could be reversed by injecting naive CD4+ T cells. Thus, our results suggested that CPT mainly inhibited breast tumor growth through inducing cytotoxic CD4+ T cells to secrete perforin. We further found that CPT enhanced perforin production of CD4+ T cells by up-regulating JAK2 and STAT4 phosphorylation. These findings suggest a novel potential therapeutic role for CPT in tumor therapy, and demonstrate that CPT performs its antitumor functions through cytotoxic CD4+ T cells.

• Journal of Ginseng Research
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• 제41권3호
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• pp.403-410
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• 2017

Background: Prenyltransferases catalyze the sequential addition of isopentenyl diphosphate units to allylic prenyl diphosphate acceptors and are classified as either trans-prenyltransferases (TPTs) or cis-prenyltransferases (CPTs). The functions of CPTs have been well characterized in bacteria, yeast, and mammals compared to plants. The characterization of CPTs also has been less studied than TPTs. In the present study, molecular cloning and functional characterization of a CPT from a medicinal plant, Panax ginseng Mayer were addressed. Methods: Gene expression patterns of PgCPT1 were analyzed by quantitative reverse transcription polymerase chain reaction. In planta transformation was generated by floral dipping using Agrobacterium tumefaciens. Yeast transformation was performed by lithium acetate and heat-shock for $rer2{\Delta}$ complementation and yeast-two-hybrid assay. Results: The ginseng genome contains at least one family of three putative CPT genes. PgCPT1 is expressed in all organs, but more predominantly in the leaves. Overexpression of PgCPT1 did not show any plant growth defect, and its protein can complement yeast mutant $rer2{\Delta}$ via possible protein-protein interaction with PgCPTL2. Conclusion: Partial complementation of the yeast dolichol biosynthesis mutant $rer2{\Delta}$ suggested that PgCPT1 is involved in dolichol biosynthesis. Direct protein interaction between PgCPT1 and a human Nogo-B receptor homolog suggests that PgCPT1 requires an accessory component for proper function.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제7권2호
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• pp.405-424
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• 2013

In publishing applications, it is advantageous to embed data in halftone images. The CPT scheme (Chen-Pan-Tseng, 2000) is a steganographic data hiding scheme that was proposed for binary images, e.g., facsimiles. The CPT scheme uses a secret key and weight matrix to protect the hidden data and can hide as many as $r={\lfloor}{\log}_2(m{\times}n+1){\rfloor}$ bits of data in the image by changing at most 2 bits in the image. Our proposed scheme also uses a secret key to protect it from being compromised and a weight matrix to increase the data hiding rate. Our scheme improves the performance of the CPT scheme by using the simple principle of splitting each block into two parts. Our proposed scheme is called improved CPT (ICPT) and has a very high embedding capacity compared to previous schemes. Experimental results demonstrate that our proposed scheme generally has higher performance than previous schemes.

• KSBB Journal
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• 제16권1호
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• pp.66-70
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• 2001

순수한 초임계 이산화탄소를 이용하여 camptothecin(CPT)와 10-hydroxy camptothecin(HCPT) 추출 시험을 결과, 이들은 각각 유기용매 메탄올 추출에 비교하여 3%와 2% 밖에 추출되지 않았다. 보조용매로 메탄올과 에탄올을 이용하여 CPT와 HCPT를 추출하면 추출 효율이 상승됨을 확인할 수 있었다. 특히 에탄올 보다 메탄올이 효율이 좋았다. 따라서 보조용매 적용에 관련된 여러 조건들을 최적화 하였다. 메탄올을 보조용매로 사용하는 경우에 보조용매의 농도가 증가할수록 추출 효율도 증가하였고 16% 이상에서는 추출 효율이 완만하게 증가하였다. 또한 추출은 온도에 따라 크게 영향을 받지 않아으나 온도에 따라 약간 증가하는 경향을 보였다. 초임계 추출에서 압력의 영향을 살펴본 결과 250 bar까지 압력이 증가할수록 추출 효율은 증가하였다. Acetate ion을 공급하여 추출 실험을 수행하였으나 CPT나 HCPT 모두 ion pairing agent의 영향은 없었다. 본 시스템과 같은 solid/fluid 추출 시스템에서 추출 효율에 영향을 크게 미치는 3가지 요소 (용해도, 확산, 및 matrix)중 확산의 영향을 살펴보았다. 여러 기하학적 모델 중 matrix가 구형인 hot-ball model로 확산게수를 계산하였다. 본 시스템에서 보조용매를 포함한 초임계 유체의 $D/r^2$ 값은 0.0072 $min^{-1}$로서 순수한 메탄올 유기용매 추출보다 큰 값을 보였다.

• Animal Bioscience
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• 제35권9호
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• pp.1327-1339
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• 2022

Objective: Fat deposition in poultry is an important factor in production performance and meat quality research. miRNAs also play important roles in regulating adipocyte differentiation process. This study was to investigate the expression patterns of miRNAs in duck adipocytes after differentiation and explore the role of miR-214 in regulating carnitine palmitoyltransferases 2 (CPT2) gene expression during duck adipocyte differentiation. Methods: Successful systems for the isolation, culture, and induction of duck primary fat cells was developed in the experiment. Using Illumina next-generation sequencing, the miRNAs libraries of duck adipocytes were established. miRanda was used to predict differentially expressed (DE) miRNAs and their target genes. The expression patterns of miR-214 and CPT2 during the differentiation were verified by quantitative real-time polymerase chain reaction and western blot. Luciferase reporter assays were used to explore the specific regions of CPT2 targeted by miR-214. We used a miR-214 over-expression strategy in vitro to further investigate its effect on differentiation process and CPT2 gene transcription. Results: There were 481 miRNAs identified in duck adipocytes, included 57 DE miRNA candidates. And the 1,046 targets genes of DE miRNAs were mainly involved in p53 signaling, FoxO signaling, and fatty acid metabolism pathways. miR-214 and CPT2 showed contrasting expression patterns before and after differentiation, and they were selected for further research. The expression of miR-214 was decreased during the first 3 days of duck adipocytes differentiation, and then increased, while the expression of CPT2 increased both in the transcriptional and protein level. The luciferase assay suggested that miR-214 targets the 3'untranslated region of CPT2. Overexpression of miR-214 not only promoted the formation of lipid droplets but also decreased the protein abundance of CPT2. Conclusion: Current study reports the expression profile of miRNAs in duck adipocytes differentiated for 4 days. And miR-214 has been proved to have the regulator potential for fat deposition in duck.

• 운동영양학회지
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• 제16권1호
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• pp.1-9
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• 2012

Long chain fatty acids (LCFAs) are transported into cells via plasma transporters, are activated to fatty acyl-CoA by fatty acyl-CoA synthase (ACS), and enter mitochondria via the carnitine system (CPT1/CACT/CPT2). The mitochondrial carnitine system plays an obligatory role in β-oxidation of LCFAs by catalyzing their transport into the mitochondrial matrix. Fatty acyl-CoAs are oxidized via the β-oxidation pathway, which results in the production of acetyl-CoA. The acetyl-CoA can be imported into the tricarboxylic acid (TCA) cycle for oxidation in the mitochondrial matrix or can be used for malonyl-CoA synthesis by acetyl-CoA carboxylase 2 (ACC2) in the cytoplasm. In skeletal muscle, ACC2 catalyzes the carboxylation of acetyl-CoA to form malonyl-CoA, which is a potent endogenous inhibitor of carnitine palmitoyltransferase 1 (CPT1). Thus, ACC2 indirectly inhibits the influx of fatty acids into the mitochondria. Fatty acid metabolism can also be regulated by malonyl-CoA-mediated inhibition of CPT1.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2009년도 춘계 학술발표회
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• pp.349-360
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• 2009

The cone penetration test(CPT) has gained its popularity in site characterization indebted by its reliability, speed, economy, and automatic measurement system since its development in the 1930s. The CPT results, commonly consisting of cone tip resistance, sleeve friction, and pore water pressure measurements, allow us to classify soils as well as to reveal their engineering characteristics. The site condition at which the CPT is allowable is often dependent on the capacity of a CPT system. In Korea, it has been considered that the CPT could be appled only to soft soils in most cases because CPT systems available for stiff soils are very rare due to their expensive procurement and maintenance cost. Luoisiana Transportation Research Center(LTRC) has developed and implemented a field-rugged continuous intrusion miniature cone penetration test(CIMCPT) system since the late 1990s. The miniature cone penetrometer has a sectional cone area of $2cm^2$ allowing system capacity reduction compared to the standard $10cm^2$ cone penetrometer. The continuous intrusion mechanism allows fast and economic site investigation. Samsung Engineering & Construction has recently developed and implemented a similar CIMCPT system based on its original version developed in LTRC. The performance of the Samsung CIMCPT system has been investigated by calibration with the standard CPT system at a well-characterized test site in Pusan, Korea. In addition, scale effect between the miniature cone penetrometer and the standard cone penetrometer has been investigated by comparing the field test results using the both systems.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• 제22권4호
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• pp.246-252
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• 2011

Background : The objective of this study was to evaluate the diagnostic efficiency of the Comprehensive Attention Test (CAT) by comparing the results of the continuous performance test (CPT) and the CAT in children and adolescents with attention-deficit hyperactivity disorder (ADHD). Method : A total of 110 children and adolescents with ADHD (mean age : 11.2${\pm}$2.9 years, 76 boys) and 36 children and adolescents without ADHD (mean age : 12.0${\pm}$2.7 years, 25 boys) completed the CAT. We compared the specificity and sensitivity of the CPT and CAT at two different cut-off points via the McNemar test. The areas under the receiver operating characteristic curves (AUC) between the two groups were compared using Medcalc software. Results : The sensitivity and specificity of the CPT were .419 and .806, respectively. The sensitivity of the CAT was .827, which was significantly higher than that of the CPT (p<.001), and the specificity of CAT is .444, which was significantly lower than that of CPT (p<.001). The AUC of the CPT and CAT was .664 and .692, respectively, and there were no significant difference between the two groups on the paired comparison (p=.513). Conclusions : The results of this study suggest that the CAT has moderate specificity and high sensitivity. The CAT can be used as a useful tool to evaluate the neuropsychological function of children and adolescents with ADHD.