• 제목/요약/키워드: Induced current

검색결과 2,676건 처리시간 0.029초

폴리에틸렌 미세플라스틱의 임신 마우스 위내 투여 및 기도 점적에 따른 신생자 간독성 평가 (Evaluation of Liver Toxicity of Neonates Following Intragastric Administration or Intratracheal Instillation of Polyethylene Microplatics to Pregnant Mice)

  • 김근우;김창열
    • 한국환경보건학회지
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    • 제48권2호
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    • pp.106-115
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    • 2022
  • Background: Current research suggests that humans are exposed to microplastics through consumption of foods and beverages, the airway route, and a variety of other means. Objectives: We evaluated oxidative stress and inflammation from polyethylene microplastics (PE-MPs) in the neonatal liver through intragastric administration or intratracheal instillation in pregnant mice. Methods: PE-MPs were administered from gestational day 9 to postnatal day 7. The intragastric administration group (0.01 mg/mouse/day or 0.1 mg/mouse/day) and intratracheal instillation group (6 ㎍/mouse/day or 60 ㎍/mouse/day) of PE-MPs were administered. After sacrifice, the oxidative stress and inflammation of the neonatal livers were measured. Results: As a result of the oxidative stress caused by PE-MPs in the neonatal livers, glutathione peroxidase decreased in a concentration-dependent manner in the intragastric administration group compared to the control group and intratracheal instillation decreased in high concentration PE-MPs. The catalase level increased at high concentrations of intragastric administration and intratracheal instillation. To confirm the level of inflammation caused by PE-MPs, monocyte chemoattractant protein-1 and tumor necrosis factoralpha were increased compared to the control group except for intratracheal intilation-high concentration PEMPs. The C-reactive protein level was decreased by intragastric administration compared to the control group and intratracheal instillation was increased compared to the control group. Conclusions: Despite the difficulty in comparing the toxic intensity between intragastric administration and intratracheal instillation of PE-MPs, our study revealed that oxidative stress and inflammation were induced in the neonatal liver. However, it is necessary to evaluate the toxic effects of microplastics on various organs as well. Overall, the present study indicates that the evaluation of toxic effects of long-term microplastic exposure, potential of microplastic toxicity on next-generation offspring and toxicity mechanism in human should be considered for further investigations.

그래핀-폴리 아닐린 복합체의 광열전 효과 연구 (Photothermoelectric Effect of Graphene-polyaniline Composites)

  • 최종완
    • Composites Research
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    • 제34권6호
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    • pp.434-439
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    • 2021
  • 그래핀과 폴리 아닐린은 기존의 무기물 기반 열전 소재의 단점을 극복하고 유연한 열전 소자에 응용할 수 있는 유기물 기반 열전 소재이다. 본 연구에서는 그래핀-폴리 아닐린 복합체를 합성하고 빛에 의해 유도되는 광열전 특성을 측정하였다. 그래핀-폴리 아닐린 복합체는 그래핀과 폴리 아닐린을 공유결합으로 연결하기 위해 산화 그래핀에 아민 작용기를 도입하였고 산화 그래핀을 다시 환원하여 환원된 산화 그래핀을 얻은 뒤 아닐린과 중합하여 그래핀-폴리 아닐린 복합체를 합성하였다. 최적의 광열전 효과를 기대하기 위해 아닐린의 함유량을 변화하여 그래핀-폴리 아닐린 복합체를 제조하였고, FT-IR과 라만 분석을 통하여 화학 구조와 조성을 확인하였다. 광전류와 광전압 특성은 외부 전기장이 없이 빛을 비대칭으로 조사하여 아닐린 함유량에 따른 전류와 전압을 분석하였다. 아닐린의 함량이 증가할수록 그래핀-폴리 아닐린 복합체의 광전류가 증가하는 전기 전도도와 같은 경향을 보였고 광전압은 빛에 의해 열에너지로 전환되어 나타나는 그래핀-폴리 아닐린 복합체의 온도변화와 관련 있음을 확인하였다.

CBP-Mediated Acetylation of Importin α Mediates Calcium-Dependent Nucleocytoplasmic Transport of Selective Proteins in Drosophila Neurons

  • Cho, Jae Ho;Jo, Min Gu;Kim, Eun Seon;Lee, Na Yoon;Kim, Soon Ha;Chung, Chang Geon;Park, Jeong Hyang;Lee, Sung Bae
    • Molecules and Cells
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    • 제45권11호
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    • pp.855-867
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    • 2022
  • For proper function of proteins, their subcellular localization needs to be monitored and regulated in response to the changes in cellular demands. In this regard, dysregulation in the nucleocytoplasmic transport (NCT) of proteins is closely associated with the pathogenesis of various neurodegenerative diseases. However, it remains unclear whether there exists an intrinsic regulatory pathway(s) that controls NCT of proteins either in a commonly shared manner or in a target-selectively different manner. To dissect between these possibilities, in the current study, we investigated the molecular mechanism regulating NCT of truncated ataxin-3 (ATXN3) proteins of which genetic mutation leads to a type of polyglutamine (polyQ) diseases, in comparison with that of TDP-43. In Drosophila dendritic arborization (da) neurons, we observed dynamic changes in the subcellular localization of truncated ATXN3 proteins between the nucleus and the cytosol during development. Moreover, ectopic neuronal toxicity was induced by truncated ATXN3 proteins upon their nuclear accumulation. Consistent with a previous study showing intracellular calcium-dependent NCT of TDP-43, NCT of ATXN3 was also regulated by intracellular calcium level and involves Importin α3 (Imp α3). Interestingly, NCT of ATXN3, but not TDP-43, was primarily mediated by CBP. We further showed that acetyltransferase activity of CBP is important for NCT of ATXN3, which may acetylate Imp α3 to regulate NCT of ATXN3. These findings demonstrate that CBP-dependent acetylation of Imp α3 is crucial for intracellular calcium-dependent NCT of ATXN3 proteins, different from that of TDP-43, in Drosophila neurons.

A plant-based multivitamin, multimineral, and phytonutrient supplementation enhances the DNA repair response to metabolic challenges

  • Yeo, Eunji;Hong, Jina;Kang, Seunghee;Lee, Wonyoung;Kwon, Oran;Park, Eunmi
    • Journal of Nutrition and Health
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    • 제55권4호
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    • pp.450-461
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    • 2022
  • Purpose: DNA damage and repair responses are induced by metabolic diseases and environmental stress. The balance of DNA repair response and the antioxidant system play a role in modulating the entire body's health. This study uses a high-fat and high-calorie (HFC) drink to examine the new roles of a plant-based multivitamin/mineral supplement with phytonutrients (PMP) for regulating the antioxidant system and cellular DNA repair signaling in the body resulting from metabolic stress. Methods: In a double-blind, randomized, parallel-arm, and placebo-controlled trial, healthy adults received a capsule containing either a PMP supplement (n = 12) or a placebo control (n = 12) for 8 weeks. Fasting blood samples were collected at 0, 1, and 3 hours after consuming a HFC drink (900 kcal). The blood samples were analyzed for the following oxidative stress makers: areas under the curve reactive oxygen species (ROS) levels, plasma malondialdehyde (MDA), erythrocytes MDA, urinary MDA, oxidized low-density lipoprotein, and the glutathione:oxidized glutathione ratio at the time points. We further examined the related protein levels of DNA repair signaling (pCHK1 (Serine 345), p-P53 (Serine 15), and 𝛄H2AX expression) in the plasma of subjects to evaluate the time-dependent effects of a HFC drink. Results: In a previous study, we showed that PMP supplementation for eight weeks reduces the ROS and endogenous DNA damage in human blood plasma. Results of the current study further show that PMP supplementation is significantly correlated with antioxidant defense. Compared to the placebo samples, the blood plasma obtained after PMP supplementation showed enhanced DNA damage response genes such as pCHK1(Serine 345) (a transducer of DNA response) and 𝛄H2AX (a hallmark of DNA damage) during the 8 weeks trial on metabolic challenges. Conclusion: Our results indicate that PMP supplementation for 8 weeks enhances the antioxidant system against oxidative stress and prevents DNA damage signaling in humans.

자세변화에 따른 PNF 다리패턴 적용이 반대측 볼기근과 배가로근에 미치는 영향: 예비 연구 (Effect of PNF Leg Pattern Application According to Posture on Muscle Activation of the Contralateral Gluteus and Transverse Abdominis: A Preliminary Study)

  • 채정병;정주현;정다은
    • PNF and Movement
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    • 제20권2호
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    • pp.285-293
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    • 2022
  • Purpose: The purpose of this study was to confirm that the activation of the contralateral muscles changes according to posture after applying the proprioceptive neuromuscular facilitation leg pattern. Methods: Ten healthy adults (four males and six females) with no history of current musculoskeletal/neurological injuries were recruited for this study. Abdominal muscle (transverse abdominis) and hip joint muscle (gluteus maximus and gluteus medius) activation was assessed using surface electromyography (Ultium EMG, Noraxon Inc., USA). We evaluated muscle activation during the application of the PNF leg pattern. The data were analyzed using the SPSS version 21.0 program. Results: The results were found to be statistically significantly different in the 90/90 supine posture and sitting posture for the gluteus maximus (p < 0.05). The results were found to be not statistically significantly different for the transverse abdominis according to posture (p > 0.05). The results were found to be not statistically significantly different for the gluteus medius according to posture (p > 0.05). Conclusion: Application of the PNF leg pattern resulted in a significant change in the muscle activation of the contralateral segment according to posture, and the 90/90 supine posture induced high muscle activation of the gluteus maximus. In addition, the activation of the transverse abdominis was high in all three postures.

청년층의 성별에 따른 남용약물에 대한 사용실태와 인식 (Current Status and Perception of Abused Drugs by Gender Among Young People)

  • 정현주;박정숙
    • 산업융합연구
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    • 제21권2호
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    • pp.79-84
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    • 2023
  • 본 연구는 청소년층에서 성인층으로 진입하는 청년층의 성별에 따른 남용약물에 대한 사용실태와 인식을 살펴 보기 위해 분석 가능한 설문지 1051부를 토대로 분석하였다. 설문에 참여한 청년들의 성별을 보면 남자 686명, 여자 365명이었으며, 성별에 따라 남용되는 약물의 종류와 마약류 및 남용약물에 대한 폐해 인식에 대해 분석하였다. 연구결과 술, 담배, 식욕억제제, 진정수면제, 아편계열 진통제 사용 경험이 성별에 따라 통계적으로 유의하였으며, 마약류 및 남용약물에 대한 폐해 인식 중 위험성과 유발문제인식, 위험성에 대한 공감에 대해서도 유의한 결과를 보였다. 마약류 및 약물남용 문제를 개선하기 위한 바람직한 방안은 여성은 257명(68.2%)가 홍보(계몽) 활동을 원하는 것으로 나타났으며, 마약류 및 약물남용 예방을 위한 효과적인 교육에 대해서 남성은 379명(54.2%)이 인터넷 온라인교육으로 나타났다. 남용약물에 의한 청년층의 약물 중독이 증가하고 있는 현실에서 약물사용에 대한 올바른 교육과 홍보가 필요하다고 사료된다.

Tramadol as a Voltage-Gated Sodium Channel Blocker of Peripheral Sodium Channels Nav1.7 and Nav1.5

  • Chan-Su, Bok;Ryeong-Eun, Kim;Yong-Yeon, Cho;Jin-Sung, Choi
    • Biomolecules & Therapeutics
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    • 제31권2호
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    • pp.168-175
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    • 2023
  • Tramadol is an opioid analog used to treat chronic and acute pain. Intradermal injections of tramadol at hundreds of millimoles have been shown to produce a local anesthetic effect. We used the whole-cell patch-clamp technique in this study to investigate whether tramadol blocks the sodium current in HEK293 cells, which stably express the pain threshold sodium channel Nav1.7 or the cardiac sodium channel Nav1.5. The half-maximal inhibitory concentration of tramadol was 0.73 mM for Nav1.7 and 0.43 mM for Nav1.5 at a holding potential of -100 mV. The blocking effects of tramadol were completely reversible. Tramadol shifted the steady-state inactivation curves of Nav1.7 and Nav1.5 toward hyperpolarization. Tramadol also slowed the recovery rate from the inactivation of Nav1.7 and Nav1.5 and induced stronger use-dependent inhibition. Because the mean plasma concentration of tramadol upon oral administration is lower than its mean blocking concentration of sodium channels in this study, it is unlikely that tramadol in plasma will have an analgesic effect by blocking Nav1.7 or show cardiotoxicity by blocking Nav1.5. However, tramadol could act as a local anesthetic when used at a concentration of several hundred millimoles by intradermal injection and as an antiarrhythmic when injected intravenously at a similar dose, as does lidocaine.

Microbiota, co-metabolites, and network pharmacology reveal the alteration of the ginsenoside fraction on inflammatory bowel disease

  • Dandan Wang;Mingkun Guo;Xiangyan Li;Daqing Zhao;Mingxing Wang
    • Journal of Ginseng Research
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    • 제47권1호
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    • pp.54-64
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    • 2023
  • Background: Panax ginseng Meyer (P. ginseng) is a traditional natural/herbal medicine. The amelioration on inflammatory bowel disease (IBD) activity rely mainly on its main active ingredients that are referred to as ginsenosides. However, the current literature on gut microbiota, gut microbiota-host co-metabolites, and systems pharmacology has no studies investigating the effects of ginsenoside on IBD. Methods: The present study was aimed to investigate the role of ginsenosides and the possible underlying mechanisms in the treatment of IBD in an acetic acid-induced rat model by integrating metagenomics, metabolomics, and complex biological networks analysis. In the study ten ginsenosides in the ginsenoside fraction (GS) were identified using Q-Orbitrap LC-MS. Results: The results demonstrated the improvement effect of GS on IBD and the regulation effect of ginsenosides on gut microbiota and its co-metabolites. It was revealed that 7 endogenous metabolites, including acetic acid, butyric acid, citric acid, tryptophan, histidine, alanine, and glutathione, could be utilized as significant biomarkers of GS in the treatment of IBD. Furthermore, the biological network studies revealed EGFR, STAT3, and AKT1, which belong mainly to the glycolysis and pentose phosphate pathways, as the potential targets for GS for intervening in IBD. Conclusion: These findings indicated that the combination of genomics, metabolomics, and biological network analysis could assist in elucidating the possible mechanism underlying the role of ginsenosides in alleviating inflammatory bowel disease and thereby reveal the pathological process of ginsenosides in IBD treatment through the regulation of the disordered host-flora co-metabolism pathway.

Peptides derived from high voltage-gated calcium channel β subunit reduce blood pressure in rats

  • Hyung Kyu Kim;Jiyeon Jun;Tae Wan Kim;Dong-ho Youn
    • The Korean Journal of Physiology and Pharmacology
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    • 제27권5호
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    • pp.481-491
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    • 2023
  • The β subunits of high voltage-gated calcium channels (HGCCs) are essential for optimal channel functions such as channel gating, activation-inactivation kinetics, and trafficking to the membrane. In this study, we report for the first time the potent blood pressure-reducing effects of peptide fragments derived from the β subunits in anesthetized and non-anesthetized rats. Intravenous administration of 16-mer peptide fragments derived from the interacting regions of the β1 [cacb1(344-359)], β2 [cacb2(392-407)], β3 [cacb3(292-307)], and β4 [cacb4(333-348)] subunits with the main α-subunit of HGCC decreased arterial blood pressure in a dose-dependent manner for 5-8 min in anesthetized rats. In contrast, the peptides had no effect on the peak amplitudes of voltage-activated Ca2+ current upon their intracellular application into the acutely isolated trigeminal ganglion neurons. Further, a single mutated peptide of cacb1(344-359)-cacb1(344-359)K357R-showed consistent and potent effects and was crippled by a two-amino acid-truncation at the N-terminal or C-terminal end. By conjugating palmitic acid with the second amino acid (lysine) of cacb1(344-359)K357R (named K2-palm), we extended the blood pressure reduction to several hours without losing potency. This prolonged effect on the arterial blood pressure was also observed in non-anesthetized rats. On the other hand, the intrathecal administration of acetylated and amidated cacb1(344-359)K357R peptide did not change acute nociceptive responses induced by the intradermal formalin injection in the plantar surface of rat hindpaw. Overall, these findings will be useful for developing antihypertensives.

A Study on the Magnetic Properties of Ion Irradiated Cu/Co Multilayer System

  • Kim, T.Y.;Chang, G.S.;Son, J.H.;Kim, S.H.;Shin, S.W.;Chae, K.H.;Sung, M.C.;Lee, J.;Jeong, K.;Lee, Y.P.;;Whang, C.N
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2000년도 제18회 학술발표회 논문개요집
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    • pp.163-163
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    • 2000
  • In this research, we used the ion irradiation technique which has an advantae in improving intentionally the properties of surface and interface in a non-equilibrium, instead of the conventional annealing method which has been known to improve the material properties in the equilibrium stat. Cu/Co multilayered films were prepared on SiN4/SiO2/Si substrates by the electron-beam evaporation for the Co layers and the thermal evaporation for the Cu layers in a high vacuum. The ion irradiation with a 80keV Ar+ was carried out at various ion doses in a high vacuum. Hysteresis loops of the films were investigated by magneto-optical polar Kerr spectroscopy at various experimental conditions. The change of atomic structure of the films before and after the ion irradiation was studied by glancing angle x-ray diffraction, and the intermixing between Co and Cu sublayers was confirmed by Rutherford backscattering spectroscopy. The surface roughness and magneto-resistance were measured by atomic force microscopy and with a four-point probe system, respectively. During the magneto-resistance measurement, we changed temperature and the direction of magnetization. From the results of experiments, we found that the change at the interfaces of the Cu/Co multilayered film induced by ion irradiation cause the change of magnetic properties. According to the change in hysteresis loop, the surface inplane component of magnetic easy axis was isotropic before the ion irradiation, but became anisotropic upon irradiation. It was confirmed that this change influences the axial behavior of magneto-resistance. Especially, the magneto-resistance varied in accordance with an external magnetic field and the direction of current, which means that magneto-resistance also shows the uniaxial behavior.

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