• Title/Summary/Keyword: action-spectrum

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Actionspectra for Circadian Melatonin Rhythms in the Avian Pineal In Vitro

  • Kondo, Chieko;Haldar, Chandana;Tamotsu, Satoshi;Oishi, Tadashi
    • Journal of Photoscience
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    • v.9 no.2
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    • pp.249-251
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    • 2002
  • The avian pineal as well as the retina has been known to contain several types of photoreceptors with different visual pigments such as rhodopsin, iodopsin and the pineal specific opsin, pinopsin. These organs are also known to have circadian clock to regulate melatonin production. Exposure of animals to light causes a decline of the melatonin level and the phase shifts of melatonin rhythms in the pineal and retina. Therefore, the circadian clock system of these organs seem to consist of three elements, i.e., light input, oscillator and melatonin output systems. In birds, it was suggested that rhodopsin might be involved in the entrainment of pineal melatonin rhythms from the action spectrum experiment for controlling NAT activity rhythms. However, there are much more pinopsin-immunoreactive (Pino-IR) cells than rhodopsin (Rho-IR) and iodopsin (Iodo-IR) cells in the avian pineal. We found that Pino-IR cells appeared earlier embryonic stages than Rho-IR and Iodo-IR cells. So, we tried to identify the visual pigments involved in the circadian melatonin rhythms in the pineal and retina. Organ cultured pineals were exposed to monochromatic light to find out which opsin participates in regulation of melatonin rhythms. The action spectra showed a peak at 475nm, suggesting that pinopsin is the major photopigment to regulate melatonin production in birds.

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Modulatory action of enrofloxacin in lipopolysaccharide-induced hyper-activated mouse spleen cells (Lipopolysaccharide에 의해 과활성화된 마우스 비장세포에서 Enrofloxacin의 조절작용)

  • Ko, Hyeong-Ju;Joo, Hong-Gu
    • Korean Journal of Veterinary Research
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    • v.59 no.2
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    • pp.75-80
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    • 2019
  • Enrofloxacin, a fluoroquinolone, is a broad-spectrum antibiotic widely used in veterinary medicine that inhibits the action of bacterial DNA gyrase, resulting in anti-bacterial effects. This study was performed to examine whether enrofloxacin has modulatory and anti-inflammatory activity on immune cells. A few studies have reported the anti-inflammatory effects of enrofloxacin. In this study, we used mouse spleen cells treated with lipopolysaccharide (LPS) and examined the effects of enrofloxacin. Several assays were performed in LPS-treated spleen cells after the enrofloxacin treatment. Enrofloxacin inhibited the metabolic activity and mitochondrial membrane potential of LPS-treated spleen cells significantly. On the other hand, enrofloxacin did not alter the proportion of the subsets in spleen cells, and did not induce cell death. The production of tumor necrosis factor-alpha in LPS-treated spleen cells was inhibited by enrofloxacin. Overall, enrofloxacin had modulatory activity in spleen cells treated with LPS. These data may broaden the use of enrofloxacin as an antibiotic with anti-inflammatory activity in veterinary clinics.

Mechanism of Action of and Resistance to Aminoglycoside Antibiotics

  • Tanaka, Nobuo
    • Archives of Pharmacal Research
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    • v.6 no.1
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    • pp.93-102
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    • 1983
  • Waksman's group discovered SM in 1944, and opened a new field of antibiotcs: i. e. AGs. A large group of antibiotics containing aminosugar and/or aminocyclitol is called the AGs. A majority of AGs are produced by actinomycetes. In the first period, AGs effective against tuberculosis were chiefly examined. Following the studies on NM and KM, AGs active against staphyllococci and gram-negative robs were investigated. The discovery of GM and synthesis of DKB and AMK led to the studies on the third generation AGs, which show a broad antimicrobial spectrum including Pseudomonas aeruginosa and drug-resistant bacteria. Since opportunistic infection caused by drug-resistant bacteria are increasing, the third generation AGs are extensively investigated at present.

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Improving Social Interaction Between Children With Autism Spectrum Disorder and Their Neurotypical Siblings Through a Cooperative Music Playing Intervention (자폐스펙트럼장애 아동과 비장애 형제간 상호작용 향상을 위한 협력적 악기연주 프로그램 적용 사례)

  • Jung, Jin Won
    • Journal of Music and Human Behavior
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    • v.20 no.2
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    • pp.61-88
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    • 2023
  • This case study examined whether a cooperative musical instrument playing could enhance interactions between children with autism spectrum disorder (ASD) and their neurotypical (NT) siblings. It involved three children with ASD aged 7-12 years and three NT siblings aged 6-11 years. Each group, comprising a child with ASD and their NT sibling, participated in a 40-minute sessions twice weekly for eight sessions over four weeks. The intervention included three stages: simultaneous action, complementary action, and achieving a joint goal. Evaluation criteria included the initiation and response behaviors of each child, and sequential interactive behaviors and cooperative behaviors between pairs were measured. Additionally, before and after the intervention, parents and NT sibling assessed their perceived sibling relationships. Results showed increased interactive and cooperative behaviors. Post-intervention, both parents and NT siblings rated the sibling relationship highly, despite little change in sibling conflict and competition consciousness. These findings indicate that interactive instrument playing can enhance perceptions of siblings as cooperative play partners and aid in teaching them how to collaborate during interactions.

New formulated "DOX-MTX-loaded Nanoparticles" Down-regulate HER2 Gene Expression and Improve the Clinical Outcome in OSCCs Model in Rat: the Effect of IV and Oral Modalities

  • Abbasi, Mehran Mesgari;Monfaredan, Amir;Hamishehkar, Hamed;Jahanban-Esfahlan, Rana
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.21
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    • pp.9355-9360
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    • 2014
  • Background: Oral squamous cell carcinoma (OSCC) remains as one of the most difficult malignancies to control because of its high propensity for local invasion and cervical lymph node dissemination. In this study, we evaluate the efficacy of our novel pH and temperature sensitive doxorubicin-methotrexate-loaded nanoparticles (DOX-MTX NP) in affecting HER2 expression profile in OSCC model in rat. Results: DOX-MTX- nanoparticle complexes caused significant decrease in mRNA level of HER2 compared to untreated cancers (p<0.05) and this finding was more pronounced with the IV mode (p<0.000). Surprisingly, HER2 mRNA was not affected in DOX treated as compared to the control group (p>0.05). On the other hand, in the DOX-MTX NP treated group, fewer tumors characterized with advanced stage and decreased HER2 paralleled improved clinical outcome (P<0.05). Moreover, the effectiveness of the oral route in the group treated with nanodrug accounted for the enhanced bioavailability of nanoparticulated DOX-MTX compared to free DOX. Furthermore, there was no significant difference in mRNA level of HER2 (p>0.05). Conclusions: Influence of HER2 gene expression is a new feature and mechanism of action observed only in dual action DOX-MTX-NPs treated groups. Down-regulation of HER2 mRNA as a promising marker and prognosticator of OSCC adds to the cytotoxic benefits of DOX in its new formulation. Both oral and IV application of this nanodrug could be used, with no preferences in term of their safety or toxicity. As HER2 is expressed abundantly by a wide spectrum of tumors, i DOX-MTX NPs may be useful for a wide-spectrum of lesions. However, molecular mechanisms underlying HER2 down regulation induced by DOX-MTX NPs remain to be addressed.

Antimicrobial Characteristic of Prunus mune extract (매실추출물의 항균특성)

  • Ha Myung-Hee;Park Woo-Po;Lee Seung-Cheol;Choi Sung-Gil;Cho Sung-Hwan
    • Food Science and Preservation
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    • v.13 no.2
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    • pp.198-203
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    • 2006
  • Prunus mume extract showed antimicrobial efface remarkably against the wide spectrum of putrefactive and food spoilage microorganisms above 250 ppm of concentration. Their thermal and pH stabilities were effective under the range of temperature $(40^{\circ}C{\sim}120^{\circ}C)$ and $pH(3{\sim}11)$. Prunus mume extract seemed to be a natural antimicrobial ideally with the view of their effectiveness and thermal & pH stabilities. In addition, their action modes suggested that their hydrophillic components would perturb the fucntions of microbial cell membranes synergistically.

AN EXPERIMENTAL STUDY ON THE CHEMOPREVENTIVE EFFECT OF CHLOROPHYLLIN IN HAMSTER CHEEK POUCH TUMOR INDUCED BY 7, 12-DIMETHYLBENZ[A]ANTHRACENE (7, 12-dimethylbenz[a]anthracene(DMBA)로 유발된 햄스터 협낭암에서 chlorophylln의 암예방효과에 관한 실험적 연구)

  • Yoon, Kyu-Ho
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.26 no.2
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    • pp.137-145
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    • 2000
  • Carcinogenesis is a multi-stage process that generally consists of at least three steps; initiation, promotion, and progression. If one of these carcinogenic steps were suppressed or delayed, the cancer could be prevented. Cancer chemoprevention is defined to be inhibition or reversal of the carcinogenic process by the specific chemical agents and is a novel approach to cancer management alternative to conventional chemotherapy. Chlorophylln(CHL), a water-soluble derivative of chlorophyll, containing sodium and copper, has been known to be strong antimutagen in several test systems, but its mechanism of antimutagenic action is unknown. In the present experiment, the possibility of CHL as chemopreventive drugs on 7,12-dimethylbenz[a]anthracene(DMBA)-induced hamster buccal pouch carcinogenesis was investigated by mutagenicity test, carcinogenicity test, and frequency or spectrum of H-ras mutations in the both of DMBA-induced and chlorophylln-pretreated-DMBA induced tumor by polymerase chain reaction and non-isotopic restriction fragment length polymorphism. The treatment of CHL reduced the yields and multiplicity of the 0.5% DMBA-induced tumor, 86% to 62.5% and $3.7{\pm}0.6$ to $1.4{\pm}0.3$, respectively. The occurrence of histidine revertant by $20{\mu}mole$ DMBA was inhibited 25.6 to 81.7% by 1 to $5{\mu}M$ CHL in a dose-dependent manner. The mutation rates of H-ras gene in DMBA-induced and CHL-pretreated-DMBA induced tumor were 96%, 94% of which the most mutations were in codon 12/13. These results suggest that CHL inhibits the carcinogenic action of DMBA by the formation of complex between CHL and DMBA or the inhibition of the activation of DMBA in vivo. But CHL did not affect the mutation rates or its spectrum in already formed tumor.

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A Study of the Photoelectrochemical Effects of Squaraine Aggregate in Monolayer (스쿠알렌 집합체의 광전기화학적 효과에 관한 연구)

  • Young Soon Kim;Kock-Yee Law;David G. Whitten
    • Journal of the Korean Chemical Society
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    • v.37 no.7
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    • pp.642-647
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    • 1993
  • Monolayers of pure surfactant squaraine, DSSQ(4-distearyl amino phenyl-4'-dimethylaminophenylsquaraine), were deposited on $SnO_2 $ electrodes by the Langmuir-Blodgett film technique. The DSSQ film exhibits ${\lambda}_{max}$ at ∼530 nm. The absorption is significantly red-shifted from the solution of DSSQ (633 nm in chloroform), suggesting that the squaraine chromophores form aggregates in the LB film. The photogeneration of the squaraine aggregates is studied by measuring the photocurrents in photoelectrochemical cells consisting of the squaraine of the aggregates is found to parallel its absorption spectrum and quantum efficiency as high as 0.3% has been observed. While the photocurrent was attenuated exponentially when stearic acid layers (up to 8 layers) are inserted between the squaraine layer and the electrode, it is nearly extinguished when the squaraine layer is over-coated with 2 layers of stearic acid. A model for the observation is proposed and the roles of the electrolytes and oxygen on the photogeneration process will be discussed.

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Therapeutic Robot Action Design for ASD Children Using Speech Data (음성 정보를 이용한 자폐아 치료용 로봇의 동작 설계)

  • Lee, Jin-Gyu;Lee, Bo-Hee
    • Journal of IKEEE
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    • v.22 no.4
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    • pp.1123-1130
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    • 2018
  • A cat robot for the Autism Spectrum Disorders(ASD) treatment was designed and conducted field test. The designed robot had emotion expressing action through interaction by the touch, and performed a reasonable emotional expression based on Artificial Neural Network(ANN). However these operations were difficult to use in the various healing activities. In this paper, we describe a motion design that can be used in a variety of contexts and flexibly reaction with various kinds of situations. As a necessary element, the speech recognition system using the speech data collection method and ANN was suggested and the classification results were analyzed after experiment. This ANN will be improved through collecting various voice data to raise the accuracy in the future and checked the effectiveness through field test.

Seismic response of steel reinforced concrete frame-bent plant of CAP1400 nuclear power plant considering the high-mode vibration

  • Biao Liu;Zhengzhong Wang;Bo Zhang;Ningjun Du;Mingxia Gao;Guoliang Bai
    • Steel and Composite Structures
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    • v.46 no.2
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    • pp.221-236
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    • 2023
  • In order to study the seismic response of the main plant of steel reinforced concrete (SRC) structure of the CAP1400 nuclear power plant under the influence of different high-mode vibration, the 1/7 model structure was manufactured and its dynamic characteristics was tested. Secondly, the finite element model of SRC frame-bent structure was established, the seismic response was analyzed by mode-superposition response spectrum method. Taking the combination result of the 500 vibration modes as the standard, the error of the base reactions, inter-story drift, bending moment and shear of different modes were calculated. Then, based on the results, the influence of high-mode vibration on the seismic response of the SRC frame-bent structure of the main plant was analyzed. The results show that when the 34 vibration modes were intercepted, the mass participation coefficient of the vertical and horizontal vibration mode was above 90%, which can meet the requirements of design code. There is a large error between the seismic response calculated by the 34 and 500 vibration modes, and the error decreases as the number of modes increases. When 60 modes were selected, the error can be reduced to about 1%. The error of the maximum bottom moment of the bottom column appeared in the position of the bent column. Finally, according to the characteristics of the seismic influence coefficient αj of each mode, the mode contribution coefficient γj•Xji was defined to reflect the contribution of each mode to the seismic action.