• 제목/요약/키워드: V21

검색결과 3,210건 처리시간 0.037초

Peptide Micelles for Anti-cancer Drug Delivery in an Intracranial Glioblastoma Animal Model

  • Yi, Na;Lee, Minhyung
    • Bulletin of the Korean Chemical Society
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    • 제35권10호
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    • pp.3030-3034
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    • 2014
  • Bis-chloroethylnitrosourea (BCNU) is currently used as an anti-cancer drug for glioblastoma therapy. In this study, BCNU was loaded into the hydrophobic cores of R3V6 amphiphilic peptide micelles for efficient delivery into brain tumors. The scanning electron microscope (SEM) study showed that the BCNU-loaded R3V6 peptide micelles (R3V6-BCNU) formed spherical micelles. MTT assay showed that R3V6-BCNU more efficiently induced cell death in C6 glioblastoma cells than did BCNU. In the Annexin V assay, R3V6-BCNU more efficiently induced apoptosis than did BCNU alone. Furthermore, the results showed that R3V6 was not toxic to cells. The positive charges of the R3V6 peptide micelles may facilitate the interaction between R3V6-BCNU and the cellular membrane, resulting in an increase in cellular uptake of BCNU. In vivo evaluation with an intracranial glioblastoma rat model showed that R3V6-BCNU more effectively reduced tumor size than BCNU alone. The results suggest that R3V6 peptide micelles may be an efficient carrier of BCNU for glioblastoma therapy.

접촉쌍성 V523 CAS의 광도곡선 분석 (LIGHT CURVE ANALYSIS OF CONTACT BINARY SYSTEM V523 CASSIOPEIAE)

  • 김진희;정장해
    • Journal of Astronomy and Space Sciences
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    • 제19권4호
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    • pp.263-272
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    • 2002
  • 보현산 천문대의 1.8m 망원경을 이용하여 1999년 10월 19일부터 21일까지 총 3일간 W UMa형 접촉쌍성 V523 Cas를 CCD 측광관측하여 총 616 (308의 ${\Delta}$b점, 308의 ${\Delta}$v점) 개의 관측점을 얻었다. 우리의 관측점으로부터 4개의 새로운 극심시각(주극심 2개, 부극심 2개)을 산출하였다. 우리가 얻은 BV 광도곡선과 Milone et al.(1985)의 시선속도곡선을 Wilson-Devinney(WD) 방법으로 흑점이 있는 경우와 없는 경우로 나누어 광도곡선의 해를 산출하였다.

Assessment of hemagglutination activity of porcine deltacoronavirus

  • Zhang, Yunfei;Han, Li;Xia, Lu;Yuan, Yixin;Hu, Hui
    • Journal of Veterinary Science
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    • 제21권1호
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    • pp.12.1-12.6
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    • 2020
  • Porcine deltacoronavirus (PDCoV) is an emerging swine enteric coronavirus that causes diarrhea in piglets. However, the biological characteristics of PDCoV are unclear. In this study, the hemagglutination (HA) abilities of two PDCoV strains (CH-01 and HNZK-04) were investigated. Our results showed that PDCoV has the ability to agglutinate rabbit erythrocytes after virion pretreatment with trypsin or neuraminidase. Additionally, the HA assay results showed a significant positive correlation with the infectious viral titer. Our results suggest that assessing the HA activity of PDCoV may be a useful diagnostic method for investigating and surveilling PDCoV infections.

Understanding the Host Innate Immune Responses against SARS-CoV-2 Infection and COVID-19 Pathogenesis

  • Yeon-Woo Kang;Subin Park;Kun-Joo Lee;Dain Moon;Young-Min Kim;Seung-Woo Lee
    • IMMUNE NETWORK
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    • 제21권1호
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    • pp.1.1-1.16
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    • 2021
  • The emergence of a new severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has become a significant health concern worldwide. Undoubtedly, a better understanding of the innate and adaptive immune responses against SARS-CoV-2 and its relationship with the coronavirus disease 2019 (COVID-19) pathogenesis will be the sole basis for developing and applying therapeutics. This review will summarize the published results that relate to innate immune responses against infections with human coronaviruses including SARS-CoV-1 and SARS-CoV-2 in both humans and animal models. The topics encompass the innate immune sensing of the virus to the dysregulation of various innate immune cells during infection and disease progression.

혼성반도체로 제조된 염료감응형 태양전지의 전기화학적 특성 (Electrochemical Characterization of Hybrid Semiconductor-Based Dye-Sensitized Solar Cells)

  • 이성규;정의경;임지선;이영석
    • Korean Chemical Engineering Research
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    • 제49권2호
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    • pp.175-180
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    • 2011
  • 본 연구에서는, 전자의 재결합을 감소시켜 염료 감응형 태양전지의 효율을 향상시키고자 다른 에너지 준위를 갖는 $TiO_{2}$$V_{2}O_{5}$을 혼합하여 $TiO_{2}/V_{2}O_{5}$ 혼성반도체를 제조하였다. 또한 제조된 $TiO_{2}/V_{2}O_{5}$ 혼성반도체는 페인트 쉐이커를 이용하여 회쇄 후 염료 감응형 태양전지의 제조 및 전기화학적 특성 평가를 함으로써 $V_{2}O_{5}$ 혼합 및 회쇄 효과가 전지효율에 미치는 영향을 고찰하였다. I-V 곡선을 통하여 측정된 염료 감응형 태양전지의 효율은 $V_{2}O_{5}$ 혼합 및 회쇄 효과에 의하여 2.9에서 5.7%로, $TiO_{2}$ 염료 감응형 태양전지에 비하여 약 2배 증가하였다. 이러한 결과는 $TiO_{2}$의 전도대보다 낮은 전도대를 갖는 $V_{2}O_{5}$의 도입으로 효과적으로 전자를 FTO 유리에 전달하여, 전자가 염료 및 전해질과의 재결합을 감소하게 되어 에너지 전환효율이 증가된 것으로 여겨 진다. 또한, 임피던스 결과도 회쇄된 $TiO_{2}/V_{2}O_{5}$ 혼성 반도체의 효과를 나타내는 $TiO_{2}$/염료/전해질 계면의 저항감소를 보여 주었다.

Li drifted Ge 검출기에 관해서 (For the Li Drifted Germanium Detector)

  • 함창식
    • 대한전자공학회논문지
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    • 제4권2호
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    • pp.16-21
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    • 1967
  • 이 보고는 처음에 Li drifted Ge 검출기에 관해서 이 Li drifted Ge 검출기에 의한 열중성자로부터의 Cl(n, r) 반응에서 생기는 r선 스텍트로를 보여준다. 이 Li drifted Ge 검출기의 에너지 분해능은 의 122KeV에서 4.5KeV, 의 1333KeV에서 10KeV이다.

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바나듐 첨가에 의한 저탄소 구조용강의 강화 (Strengthening of 0.25%C Low Carbon Structural Steels by Vanadium Addition)

  • 이상옥;이현권;이상우
    • 열처리공학회지
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    • 제21권2호
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    • pp.79-86
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    • 2008
  • As a basic research for developing 600 MPa yield strength reinforcing steel bars, the strengthening of 0.25 wt.% carbon steel by vanadium addition was studied. The changes of microstructure and mechanical properties were investigated for the specimen V0 (0.00 wt.% V), V1 (0.03 wt.% V) and V2 (0.06 wt.% V) processed by various heat treatments. To set the heat treatment conditions, the continuous cooling transformation (CCT) curves were drawn for austenitizing temperatures of $900^{\circ}C$ and $1100^{\circ}C$. For specimens tempered at $600^{\circ}C$ after quenching from $900^{\circ}C$ and $1100^{\circ}C$, yield strength was increased by 19 MPa and 21 MPa for 0.01 wt % V addition, and tensile strength was increased by 25 MPa and 28 MPa for 0.01 wt % V addition, respectively. Also, for 0.06 wt.% V added specimens tempered after quenching and normalized, tensile strength was increased by 50 MPa and 30 MPa for increasing austenitizing temperature of $100^{\circ}C$, respectively.

SARS-CoV-2-Specific T Cell Responses in Patients with COVID-19 and Unexposed Individuals

  • Min-Seok Rha;A Reum Kim;Eui-Cheol Shin
    • IMMUNE NETWORK
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    • 제21권1호
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    • pp.2.1-2.11
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    • 2021
  • Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection causes coronavirus disease 2019 (COVID-19), an ongoing pandemic disease. In the current review, we describe SARS-CoV-2-specific CD4+ and CD8+ T-cell responses in acute and convalescent COVID-19 patients. We also discuss the relationships between COVID-19 severity and SARS-CoV-2-specific T-cell responses and summarize recent reports regarding SARS-CoV-2-reactive T cells in SARS-CoV-2-unexposed individuals. These T cells may be cross-reactive cells primed by previous infection with human common-cold coronaviruses. Finally, we outline SARS-CoV-2-specific T-cell responses in the context of vaccination. A better understanding of SARS-CoV-2-specific T-cell responses is needed to develop effective vaccines and therapeutics.

SARS-CoV-2 Infection of Airway Epithelial Cells

  • Gwanghui Ryu;Hyun-Woo Shin
    • IMMUNE NETWORK
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    • 제21권1호
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    • pp.3.1-3.16
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    • 2021
  • Coronavirus disease 2019 caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been spreading worldwide since its outbreak in December 2019, and World Health Organization declared it as a pandemic on March 11, 2020. SARS-CoV-2 is highly contagious and is transmitted through airway epithelial cells as the first gateway. SARS-CoV-2 is detected by nasopharyngeal or oropharyngeal swab samples, and the viral load is significantly high in the upper respiratory tract. The host cellular receptors in airway epithelial cells, including angiotensin-converting enzyme 2 and transmembrane serine protease 2, have been identified by single-cell RNA sequencing or immunostaining. The expression levels of these molecules vary by type, function, and location of airway epithelial cells, such as ciliated cells, secretory cells, olfactory epithelial cells, and alveolar epithelial cells, as well as differ from host to host depending on age, sex, or comorbid diseases. Infected airway epithelial cells by SARS-CoV-2 in ex vivo experiments produce chemokines and cytokines to recruit inflammatory cells to target organs. Same as other viral infections, IFN signaling is a critical pathway for host defense. Various studies are underway to confirm the pathophysiological mechanisms of SARS-CoV-2 infection. Herein, we review cellular entry, host-viral interactions, immune responses to SARS-CoV-2 in airway epithelial cells. We also discuss therapeutic options related to epithelial immune reactions to SARS-CoV-2.