• Title/Summary/Keyword: pi

Search Result 7,039, Processing Time 0.028 seconds

Elevated RalA activity in the hippocampus of PI3Kγ knock-out mice lacking NMDAR-dependent long-term depression

  • Sim, Su-Eon;Lee, Hye-Ryeon;Kim, Jae-Ick;Choi, Sun-Lim;Bakes, Joseph;Jang, Deok-Jin;Lee, Kyungmin;Han, Kihoon;Kim, Eunjoon;Kaang, Bong-Kiun
    • BMB Reports
    • /
    • v.46 no.2
    • /
    • pp.103-106
    • /
    • 2013
  • Phosphoinositide 3-kinases (PI3Ks) play key roles in synaptic plasticity and cognitive functions in the brain. We recently found that genetic deletion of $PI3K{\gamma}$, the only known member of class IB PI3Ks, results in impaired N-methyl-D-aspartate receptor-dependent long-term depression (NMDAR-LTD) in the hippocampus. The activity of RalA, a small GTP-binding protein, increases following NMDAR-LTD inducing stimuli, and this increase in RalA activity is essential for inducing NMDAR-LTD. We found that RalA activity increased significantly in $PI3K{\gamma}$ knockout mice. Furthermore, NMDAR-LTD-inducing stimuli did not increase RalA activity in $PI3K{\gamma}$ knockout mice. These results suggest that constitutively increased RalA activity occludes further increases in RalA activity during induction of LTD, causing impaired NMDAR-LTD. We propose that $PI3K{\gamma}$ regulates the activity of RalA, which is one of the molecular mechanisms inducing NMDAR-dependent LTD.

Experimental cryptosporidiosis in calves (송아지의 실험적 크립토스포리디움증)

  • Wee, Sung-hwan;Lee, Chung-gil;Kang, Yung-bai;Joo, Hoo-don;Joo, Yi-seok;Park, Yong-ho;Choi, Sang-ho
    • Korean Journal of Veterinary Research
    • /
    • v.35 no.1
    • /
    • pp.107-113
    • /
    • 1995
  • Four Holstein calves 7-day-old were infected with C parvum oocysts for parasitological and pathological investigations of bovine cryptosporidiosis. Of those calf 1 was orally administered with $7{\times}10^6$ oocysts of C parvum isolated from a Korean mouse (VRI-CN91), and calf 2 with same number of C parvum oocysts provided by Washington State University(WSU). The rest (calf 3 and 4) were orally administered with $1{\times}10^8$ oocysts of VRI-CN91 strain. Calf 1 commenced to discharge oocysts in feces at days 6 post inoculation(PI), and it reached a peak $1.4{\times}10^7$ oocysts per gram of feces(OPG) on day 8 PI. Calf 2 commenced to discharge oocysts in feces at day 4 PI, and it reached a peak $3.75{\times}10^6$ OPG on day 7 PI. Calf 3 and 4 commenced to discharge oocysts in feces at day 3 and day 4 PI, and it reached a peak on day 7 PI (calf 3, $7.8{\times}10^6$ OPG; calf 4, $1.7{\times}10^6$ OPG). Clinically, the calves began to show mucoid-watery diarrhea at day 3 to 5 PI, and the sign lasted 5 to 7 days. Calf 2 died on day 9 PI with a severe dehydration. On necropsy the intestine was found to be congested and hemorrhagic. Protozoan oocysts were observed mainly in the ileum and occasionally in jejunum. The results in the present study indicate that the Korean isolate was pathogenic in calves.

  • PDF

A Study on the Fabrication Process and Magnetic Properties of Buble Magnetic Materials. (버블자성재료의 제조 및 자기 특성에 관한 연구)

  • Park, Yong-Du;Kim, Jong-O
    • Korean Journal of Materials Research
    • /
    • v.5 no.8
    • /
    • pp.1040-1044
    • /
    • 1995
  • Magnetic garnet films of (YSmLuCa)$_3$(FeGe)$\_$5/O$\_$12/ have been grown by the liquid phase eqitaxy method on the substrate of non-magnetic garnet Gd$_3$Ga$\_$5/O$\_$12/. The variation of Sm ion concentration were varied 0.3, 0.4, 0.6, mole/formula unit respectively. The magnetic properties of the samples for the bubble magnetic materials, such as, line width ΔH of ferromagnetic resonance (FMR), magnetic saturation induction 4$\pi$Ms, wall mobility u$\_$w/ uniaxial magnetic anisotropy energy Ku, were measured and discussed the relations between these properties. The line width ΔH decreases with increasing 4$\pi$Ms, and with decreasing Sm concentration. The anisotropy energy Ku increases not only with increasing Sm ion concentration, but also increasing 4$\pi$Ms. The value of wall mobility u$\_$w/ increase with increasing 4$\pi$Ms and decreases with increasing Sm concentration. We define a physical constant Eι from the fact that the product of 4$\pi$Ms and ΔH is constant with dimension of energy density. The Eι is dependent only on Sm concentration.density. The Eι is dependent only on Sm concentration.

  • PDF

A Review on Patterns and Classification Criteria of Psoriasis by analyzing Chinese Theses (중국 논문에 나타난 건선의 변증 분석 및 변증체계에 대한 고찰)

  • Cho, Eun-Chai;Kim, Kyu-Seok
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
    • /
    • v.33 no.2
    • /
    • pp.112-129
    • /
    • 2020
  • Objectives : The aim of this study is to explore the types of pattern identification (PI, 辨證) and the differential points of PI used for the treatment of psoriasis in Traditional Chinese Medicine (TCM) based on the Chinese references and to provide the evidences applying PI for the treatment of psoriasis in clinical practice. Methods : This study extracted patterns of psoriasis through database CNKI (China National Knowledge Infrastructure) and analysis the patterns and classification criteria of the patterns. Those examined in the study are dermal symptoms, general symptoms, formula and herbs which are different depending on the patterns. Results : Total 60 studies were selected and 44 pattern types were extracted from them. We categorized the main pattern types on psoriasis used in TCM as 'blood-heat syndrome(BHS, 血熱證)', blood-stasis syndrome(BSS, 血瘀證), and 'blood-dryness syndrome(BDS, 血燥證)', 'dampness-heat syndrome(DHS, 濕熱證)' and 'yang-deficiency syndrome(YDS, 陽虛證)'. Among these patterns, BHS was the most common. In TCM, the pattern of BHS tended to have skin symptoms and signs related to inflammatory erythema and heat. Both BSS and BDS were characterized by long disease duration and poor healing. In addition, DHS tended to have the skin symptoms and signs such as oozing and severe itching. The symptoms and signs related to coldness mainly showed in YDS. For PI criteria, 'qi-blood-essence criteria(氣血津液辨證)' and 'eight-doctrine criteria(八鋼辨證) are commonly used. Conclusions : Our findings show that each PI on psoriasis in TCM has different characteristics related to dermal and general symptoms or signs. Further studies are needed to develop the diagnostic tool of PI on psoriasis reflecting on clinical practices in Korean Medicine by referring to the findings of this study about PI on psoriasis in TCM.

Development of ELISA for detection of canine brucellosis (Canine brucellosis 검출을 위한 ELISA 진단법 확립)

  • Hur, Jin;Baek, Byeong-Kirl
    • Korean Journal of Veterinary Service
    • /
    • v.34 no.2
    • /
    • pp.159-166
    • /
    • 2011
  • This study was carried out to develope enzyme-linked immunosorbent assay (ELISA) for detection of canine brucellosis in dogs experimentally inoculated with Brucella abortus 1119-3 and B. canis RM666. Groups A, B and C of dogs (each group consisting of three dogs) were orally inoculated with approximately $5{\times}10^9$ colony-forming units of B. abortus and B. canis, and with sterile pyrogen-free PBS, respectively. The animals were monitored at regular intervals upto the 12th week post inoculation (PI) by standard tube agglutination test (STAT), plate agglutination test (PAT), Rose Bengal test (RBT), 2-mercaptoethanol rapid slide agglutination test (2ME-RSAT) and ELISA. The induced antibody titers in group A dogs were detected from the first week PI to the eighth week PI in STAT, PAT and RBT using the inactivated whole cells of B. abortus 1119-3 as antigens, while no sera in groups B and C dogs reacted with the antigens. In 2ME-RSAT using whole cells of B. canis M-strain as antigens, the induced antibody titers in group B dogs were observed at the second week PI and persisted for the 12th week PI, while sera of groups A and C dogs did not react with the whole cells. In ELISA using cytoplasmic fractions antigen of B. abortus 1119-3, the mean optical density of antibodies in groups A and B was detected from the first and second weeks PI, respectively, and persisted for 12th week PI, while sera of group C did not cross-react with the fractions antigen. However, in ELISA using the hot saline extracts of B. canis M- as an antigen, the induced antibody titers in only group B dogs were detected from second week PI and persisted for until the end of this study. These results indicate that the ELISA using B. abortus 1119-3 cytoplasmic fractions as antigens can be a good candidate for detection of brucellosis by B. abortus as well as B. canis in dogs.

PI3-Kinase and PDK-1 Regulate HDAC1-mediated Transcriptional Repression of Transcription Factor NF-κB

  • Choi, Yong Seok;Jeong, Sunjoo
    • Molecules and Cells
    • /
    • v.20 no.2
    • /
    • pp.241-246
    • /
    • 2005
  • PDK-1 activates PI3-kinase/Akt signaling and regulates fundamental cellular functions, such as growth and survival. NF-${\kappa}B$ is involved in the induction of a variety of cellular genes affecting immunity, inflammation and the resistance to apoptosis induced by some anti-cancer drugs. Even though the crucial involvement of the PI3-kinase/Akt pathway in the anti-apoptotic activation of NF-${\kappa}B$ is well known, the exact role of PDK-1 as well as PI3-kinase/Akt in NF-vactivation is not understood. Here we demonstrate that PDK-1 plays a pivotal role in transcriptional activation of NF-${\kappa}B$ by dissociating the transcriptional co-repressor HDAC1 from the p65 subunit of NF-${\kappa}B$. The association of CBP with p65 was not directly modulated by PDK-1 or by PI3-kinase. Etoposide activated NF-${\kappa}B$ through PI3-kinase/Akt, and the transcription activation domain (TAD) of p65 was further activated by wild-type PDK-1. Overexpression of a dominant negative PDK-1 mutant decreased etoposide-induced NF-${\kappa}B$ transcription and further down-regulated the ectopic HDAC1-mediated decrease in NF-${\kappa}B$ transcriptional activity. Thus activation of PDK-1 relieves the HDAC1-mediated repression of NF-${\kappa}B$ that may be related to basal as well as activated transcription by NF-${\kappa}B$. This effect may also explain the role of the PI3-kinase/PDK-1 pathway in the anti-apoptotic function of NF-${\kappa}B$ associated with the chemoresistance of cancer cells.

Prevalence for persistently infected cattle with bovine viral diarrhea virus in Korea (국내 한우의 소바이러스성 설사 바이러스 지속감염우에 대한 실태 조사)

  • Cho, Jong-Suk;Kim, Gyung-Dong;Park, Hong-Je;Lim, Yeoun-Su;Hong, Sung-Hee;Seo, Chang-Won;Ryu, Hee-Jeong;Sin, Ryeong-Ja
    • Korean Journal of Veterinary Service
    • /
    • v.36 no.2
    • /
    • pp.105-110
    • /
    • 2013
  • Bovine viral diarrhea virus (BVDV) is very important disease in domestic and wild ruminants and has a world wide distribution. Cattle persistently infected with BVDV (BVDV-PI) are the primary reservoir for BVDV infection in Korean native cattle herds. The prevalence of cattle persistently infected with BVDV (BVD-PI) was determined using 4,260 heads from 29 Korean native cattle farms at 8 districts from 2011 to 2012. The sera and ear nothches were collected for each sample. We surveyed BVD-PI cattle using antibody ELISA and antigen capture ELISA for detection of antibody and antigen respectively. Three thousand seventy-six cattle (72.2%) were positive for BVDV antibody and a total of 27 BVD-PI cattle were found in 12 farms. 11 cattle (40.7%) out of the total 27 BVDV-PI cattle were six months old or under. The positive rate of BVDV antibody (83.2%) from 12 farms with BVD-PI cattle was higher than the positive rate of BVDV antibody (63.6%) from 17 farms without BVD-PI cattle.

Photoelectrochemical Water Oxidation Using ZnO Nanorods Coupled with Cobalt-Based Catalysts

  • Jeon, Tae-Hwa;Choi, Sung-Kyu;Jeong, Hye-Won;Kim, Seung-Do;Park, Hyun-Woong
    • Journal of Electrochemical Science and Technology
    • /
    • v.2 no.4
    • /
    • pp.187-192
    • /
    • 2011
  • Photoelectrochemical performances of ZnO electrodes are enhanced by coupling with cobalt-based catalyst (CoPi) in phosphate electrolyte (pH 7). For this study, hexagonal pillar-shaped ZnO nanorods are grown on ZnO electrodes through a chemical bath deposition, onto which CoPi is deposited with different photodeposition times (10-30 min). A scanning electron microscopic study indicates that CoPi deposition does not induce any change of ZnO morphology and an energy-dispersive X-ray spectroscopic analysis shows that inorganic phosphate ions (Pi) exist on ZnO surface. Bare ZnO electrodes generate the current of ca. $0.36mA/cm^2$ at a bias potential of 0.5 V vs. SCE, whereas ZnO/CoPi (deposited for 10 min) has ca. 50%-enhanced current ($0.54mW/cm^2$) under irradiation of AM 1.5G-light ($400mW/cm^2$). The excess loading of CoPi on ZnO results in decrease of photocurrents as compared to bare ZnO likely due to limited electrolyte access to ZnO and/or CoPi-mediated recombination of photogenerated charge carriers. The primary role of CoPi is speculated to trap the photogenerated holes and thereby oxidize water into molecular oxygen via an intervalency cycle among Co(II), Co(III), and Co(IV).

Purification and Characterization of Membrane-Bound Phosphatidylinositol 4-Kinase from Mouse Brain

  • Lee, Sang-Min;Son, Hyeog-Gin;Lee, Young-Seek;Lee, Kang-Suk;Rhee, Sue-Goo;Cho, Key-Seung
    • BMB Reports
    • /
    • v.29 no.6
    • /
    • pp.555-563
    • /
    • 1996
  • A membrane-bound phosphatidylinositol 4-kinase (PI 4-kinase) was separated in a sucrose gradient and solubilized with 1% Triton X-100 from mouse brain. The enzyme was purified 2,952-fold by various chromatographic techniques including DEAE-cellulose, PI-Sepharose and Sephacryl S-200 gel filtration. The molecular weight of PI 4-kinase was approximately 76 kDa by gel filtration and 70.8 kDa by SDS-polyacrylamide gel electrophoresis. The purified enzyme exhibited specific activity of 11.2 nmol/min/mg protein and pi value of 4.7. Kinetic analysis of the PI 4-kinase indicated apparent $K_m$, values of 190 ${\mu}M$ and 120 ${\mu}M$ for phosphatidylinositol and ATP, respectively. The maximal activity of this purified enzyme was observed at pH 7.4 at an incubation temperature of $37^{\circ}C$. The enzyme activity was significantly activated by $Mg^{2+}$, $Mn^{2+}$ and $Fe^{2+}$, and inhibited severely by $Ca^{2+}$. PI 4-kinase was proved to be pure in its immunoblot test by polyclonal antibody prepared from immunized rabbit sera. By this test, we were able to detect the existence of the same type of PI 4-kinase from other mouse organ tissues, such as liver, heart, kidney and spleen. Furthermore, similar immunoblot analysis with the same antisera recognized the different epitopes of PI 4-kinase proteins from various organs of rabbit, chinese hamster and rat.

  • PDF

A Performance Analysis Based on Hadoop Application's Characteristics in Cloud Computing (클라우드 컴퓨팅에서 Hadoop 애플리케이션 특성에 따른 성능 분석)

  • Keum, Tae-Hoon;Lee, Won-Joo;Jeon, Chang-Ho
    • Journal of the Korea Society of Computer and Information
    • /
    • v.15 no.5
    • /
    • pp.49-56
    • /
    • 2010
  • In this paper, we implement a Hadoop based cluster for cloud computing and evaluate the performance of this cluster based on application characteristics by executing RandomTextWriter, WordCount, and PI applications. A RandomTextWriter creates given amount of random words and stores them in the HDFS(Hadoop Distributed File System). A WordCount reads an input file and determines the frequency of a given word per block unit. PI application induces PI value using the Monte Carlo law. During simulation, we investigate the effect of data block size and the number of replications on the execution time of applications. Through simulation, we have confirmed that the execution time of RandomTextWriter was proportional to the number of replications. However, the execution time of WordCount and PI were not affected by the number of replications. Moreover, the execution time of WordCount was optimum when the block size was 64~256MB. Therefore, these results show that the performance of cloud computing system can be enhanced by using a scheduling scheme that considers application's characteristics.