• 제목/요약/키워드: blocking effect

검색결과 904건 처리시간 0.024초

자외선차단 기능을 갖는 폴리실세스퀴옥산 구형 입자의 개발 (Development of UV-screening Polysilsesquioxane Spheres)

  • 윤경섭;임미선;김영백;정택규
    • 대한화장품학회지
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    • 제31권1호
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    • pp.65-71
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    • 2005
  • 자외선 차단제로 널리 사용되는 p-methoxycinnamoyl기를 함유하는 폴리실세스퀴옥산 전구체를 합성하고 그로부터 자외선을 흡수 차단하는 구 형태의 입자를 제조하였다. 여러 가지 제조 조건을 조절하여 100nm에서 수 ${\mu}m$ 사이의 직경을 가진 구를 제조하였으며, 얻어진 구의 피부 도포와 자외선차단 실험을 수행하였다. 직영이 대략 $0.6{\mu}m$인 구를 $10\%$의 농도로 바셀린에 분산시킨 제재를 손등에 도포하였을 때 백화현상이 나타나지 않았고 $10\%$ 농도 바셀린 제재의 자외선차단지수, SPF는 5.7로 양호한 편이었다. 또한 자외선을 흡수 차단하는 폴리실세스퀴옥산 구는 옥틸메톡시신나메이트 자외선차단제에 비하여 농도 증가시 SPF의 상승효과가 커, 자외선차단용 기능성화장품 신소재로의 사용이 기대된다.

OAS1 and OAS3 negatively regulate the expression of chemokines and interferon-responsive genes in human macrophages

  • Lee, Wook-Bin;Choi, Won Young;Lee, Dong-Hyun;Shim, Hyeran;KimHa, Jeongsil;Kim, Young-Joon
    • BMB Reports
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    • 제52권2호
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    • pp.133-138
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    • 2019
  • Upon viral infection, the 2', 5'-oligoadenylate synthetase (OAS)-ribonuclease L (RNaseL) system works to cleave viral RNA, thereby blocking viral replication. However, it is unclear whether OAS proteins have a role in regulating gene expression. Here, we show that OAS1 and OAS3 act as negative regulators of the expression of chemokines and interferon-responsive genes in human macrophages. Clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR-associated protein-9 nuclease (Cas9) technology was used to engineer human myeloid cell lines in which the OAS1 or OAS3 gene was deleted. Neither OAS1 nor OAS3 was exclusively responsible for the degradation of rRNA in macrophages stimulated with poly(I:C), a synthetic surrogate for viral double-stranded (ds)RNA. An mRNA sequencing analysis revealed that genes related to type I interferon signaling and chemokine activity were increased in $OAS1^{-/-}$ and $OAS3^{-/-}$ macrophages treated with intracellular poly(I:C). Indeed, retinoic-acid-inducible gene (RIG)-I- and interferon-induced helicase C domain-containing protein (IFIH1 or MDA5)-mediated induction of chemokines and interferon-stimulated genes was regulated by OAS3, but Toll-like receptor 3 (TLR3)- and TLR4-mediated induction of those genes was modulated by OAS1 in macrophages. However, stimulation of these cells with type I interferons had no effect on OAS1- or OAS3-mediated chemokine secretion. These data suggest that OAS1 and OAS3 negatively regulate the expression of chemokines and interferon-responsive genes in human macrophages.

Pre- and Postsynaptic Actions of Reactive Oxygen Species and Nitrogen Species in Spinal Substantia Gelatinosa Neurons

  • Park, Areum;Chun, Sang Woo
    • International Journal of Oral Biology
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    • 제43권4호
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    • pp.209-216
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    • 2018
  • Reactive oxygen species (ROS) and nitrogen species (RNS) are involved in cellular signaling processes as a cause of oxidative stress. According to recent studies, ROS and RNS are important signaling molecules involved in pain transmission through spinal mechanisms. In this study, a patch clamp recording was used in spinal slices of rats to investigate the action mechanisms of $O_2{^{{\bullet}_-}}$ and NO on the excitability of substantia gelatinosa (SG) neuron. The application of xanthine and xanthine oxidase (X/XO) compound, a ROS donor, induced inward currents and increased the frequency of spontaneous excitatory postsynaptic currents (sEPSC) in slice preparation. The application of S-nitroso-N-acetyl-DL-penicillamine (SNAP), a RNS donor, also induced inward currents and increased the frequency of sEPSC. In a single cell preparation, X/XO and SNAP had no effect on the inward currents, revealing the involvement of presynaptic action. X/XO and SNAP induced a membrane depolarization in current clamp conditions which was significantly decreased by the addition of thapsigargin to an external calcium free solution for blocking synaptic transmission. Furthermore, X/XO and SNAP increased the frequency of action potentials evoked by depolarizing current pulses, suggesting the involvement of postsynaptic action. According to these results, it was estblished that elevated ROS and RNS in the spinal cord can sensitize the dorsal horn neurons via pre- and postsynaptic mechanisms. Therefore, ROS and RNS play similar roles in the regulation of the membrane excitability of SG neurons.

Synthesis and biodistribution of 18F-labeled α-, β- and ω-fluorohexadecanoic acid

  • Lee, Yun-Sang;Kim, Young Joo;Cheon, Gi Jeong;Jeong, Jae Min
    • 대한방사성의약품학회지
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    • 제4권2호
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    • pp.57-64
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    • 2018
  • ${\omega}-[^{18}F]$-Fluorohexadecanoic acid (FHA) has been used for imaging of fatty acid metabolism of myocardium. To increase retention of radiolabeled fatty acid by blocking ${\beta}$-oxidation, methyl branched analogues have been used. In this experiment, we tried to synthesize 18F-labeled ${\alpha}-$, ${\beta}-$ and ${\omega}-FHA$ for imaging of the myocardial fatty acid metabolism. We synthesized ${\alpha}-$, ${\beta}-$ and ${\omega}$-mesylated methyl hexadecanoates and labeled with $^{18}F$ by reacting with $[^{18}F]$TBAF in acetonitrile at $80^{\circ}C$ for 10 min. Methyl ester group was removed by 1 M NaOH at $80^{\circ}C$ for 5 min. The yields of ${\alpha}-[^{18}F]$ and ${\omega}-[^{18}F]FHA$ were 25.5 and 45.5%, respectively [EOS]. However, ${\beta}-[^{18}F]FHA$ was not labeled at all due to a fast elimination reaction. The biodistribution study in ICR-mice showed that ${\omega}-[^{18}F]FHA$ has higher myocardial uptake and lower liver uptake than ${\alpha}-[^{18}F]FHA$. The electron-withdrawing effect of fluorine at ${\alpha}-$ position is believed to be the major factor affecting the biodistribution.

Agastache rugosa Kuntze Attenuates UVB-Induced Photoaging in Hairless Mice through the Regulation of MAPK/AP-1 and TGF-β/Smad Pathways

  • Yun, Mann-Seok;Kim, Changhee;Hwang, Jae-Kwan
    • Journal of Microbiology and Biotechnology
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    • 제29권9호
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    • pp.1349-1360
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    • 2019
  • Chronic exposure to ultraviolet (UV) radiation, regarded as a major cause of extrinsic aging or photoaging characterized by wrinkle formation and skin dehydration, exerts adverse effects on skin by causing the overproduction of reactive oxygen species. Agastache rugosa Kuntze, known as Korean mint, possesses a wide spectrum of biological properties including anti-oxidation, anti-inflammation, and anti-atherosclerosis. Previous studies have reported that A. rugosa protected human keratinocytes against UVB irradiation by restoring the anti-oxidant defense system. However, the anti-photoaging effect of A. rugosa extract (ARE) in animal models has not yet been evaluated. ARE was orally administered to hairless mice at doses of 100 or 250 mg/kg/day along with UVB exposure for 12 weeks. ARE histologically improved UVB-induced wrinkle formation, epidermal thickening, erythema, and hyperpigmentation. In addition, ARE recovered skin moisture by improving skin hydration and transepidermal water loss (TEWL). Along with this, ARE increased hyaluronic acid levels by upregulating HA synthase genes. ARE markedly increased the density of collagen and the amounts of hydroxypoline via two pathways. First, ARE significantly downregulated the mRNA expression of matrix metalloproteinases responsible for collagen degradation by inactivating the mitogen-activated protein kinase/activator protein 1 pathway. Second, ARE stimulated the transforming growth factor beta/Smad signaling, consequently raising the mRNA levels of collagen-related genes. In addition, ARE not only increased the mRNA expression of anti-oxidant enzymes but also decreased inflammatory cytokines by blocking the protein expression of nuclear factor kappa B. Collectively, our findings suggest that A. rugosa may be a potential preventive and therapeutic agent for photoaging.

경옥 가루 표면 개질과 화장품에의 응용을 위한 제형 연구 (Formulation Studies for Surface Modification and Application to Cosmetics of Jadeite Powder)

  • 김용우;박수남
    • 공업화학
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    • 제30권2호
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    • pp.167-177
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    • 2019
  • 경옥 가루는 화장품 제형에 적용 시 분체의 응집 현상으로 인해 제형 안정성에 영향을 주는 단점이 있다. 이러한 문제점을 개선코자 경옥 가루 표면 개질을 통한 새로운 복합 분체를 개발하였고 이를 고형 밤 파운데이션과 선 스틱에 적용하였다. 본 연구에서는 다양한 표면 개질제 중 triethoxycaprylylsilane을 최적의 성분으로 선정하였고 경옥 가루 복합체를 제조하여 각 제형에 적용하였다. 그 결과 고형 밤 파운데이션에서는 제품 자체 색상에 대한 선명도를 유지해 주는 역할을 했고, 선 스틱의 경우는 UVB 영역에서 기존 대비 약 30% 향상된 자외선 차단 효과를 나타내었다. 관능평가에서 경옥 가루 복합체를 함유하는 제형은 전반적인 지표에서 높은 점수를 나타내었다. 안정성 평가 결과에서는 변색, 변취 및 경도 변화에 대해 안정성이 확인되었다. 결론적으로 경옥 가루 복합체는 무기안료로써 제형 안정성이 확보되었으며, 제품의 색채 선명성 유지 및 자외선 차단제의 부스터 역할도 수행하는 다기능 소재로써 화장품에 응용가능성이 있음을 확인하였다.

Vaccinium oldhamii Stems Inhibit Pro-inflammatory Response and Osteoclastogenesis through Inhibition of NF-κB and MAPK/ATF2 Signaling Activation in LPS-stimulated RAW264.7 Cells

  • Park, Su Bin;Kim, Ha Na;Kim, Jeong Dong;Jeong, Jin Boo
    • 한국자원식물학회:학술대회논문집
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    • 한국자원식물학회 2019년도 추계학술대회
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    • pp.67-67
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    • 2019
  • Vaccinium oldhamii (V. oldhamii) has been reported to exert a variety of the pharmacological properties such as anti-oxidant activity, anti-cancer activity, and inhibitory activity of ${\alpha}$-amylase and acetylcholinesterase. However, the anti-inflammatory activity of V. oldhamii has not been studied. In this study, we aimed to investigate anti-inflammatory activity of the stem extracts from V. oldhamii, and to elucidate the potential mechanisms in LPS-stimulated RAW264.7 cells. Among VOS, VOL and VOF, the inhibitory effect of NO and PGE2 production induced by LPS was highest in VOS treatment. Thus, VOS was selected for the further study. VOS dose-dependently blocked LPS-induced NO and PGE2 production by inhibiting iNOS and COX-2 expression, respectively. VOS inhibited the expression of pro-inflammatory cytokines such as $IL-1{\beta}$, IL-6 and $TNF-{\alpha}$. In addition, VOS suppressed TRAP activity and attenuated the expression of the osteoclast-specific genes such as NFATc1, c-FOS, TRAP, MMP-9, cathepsin K, CA2, OSCAR and ATPv06d2. VOS inhibited LPS-induced $NF-{\kappa}B$ signaling activation through blocking $I{\kappa}B-{\alpha}$ degradation and p65 nuclear accumulation. VOS inhibited MAPK signaling activation by attenuating the phosphorylation of ERK1/2, p38 and JNK. Furthermore, VOS inhibited ATF2 phosphorylation and blocked ATF2 nuclear accumulation. From these findings, VOS has potential to be a candidate for the development of chemopreventive or therapeutic agents for the inflammatory diseases.

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DRDoS 증폭 공격 대응 시스템 (Response System for DRDoS Amplification Attacks)

  • 김효종;한군희;신승수
    • 융합정보논문지
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    • 제10권12호
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    • pp.22-30
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    • 2020
  • 정보통신기술의 발전에 따라 DDoS와 DRDoS은 지속적으로 보안상 이슈가 되고, 고도화된 기법으로 점차 발전하고 있다. 최근에는 정상 서버의 프로토콜을 이용하여 반사 서버로 악용하는 DRDoS 기법으로 IT 기업들을 위협하고 있다. 반사 트래픽은 정상적인 서버에서 발생되는 트래픽으로 보안장비에서 판별하기가 어렵고 실제 사례에서도 최대 Tbps 까지 증폭되었다. 본 논문에서는 DRDoS 공격에서 사용되는 DNS증폭과 Memcached증폭을 비교 분석한 뒤 공격의 효과를 감소시킬 수 있는 대응방안을 제안한다. 반사 트래픽으로 사용되는 프로토콜은 TCP와 UDP, 그리고 NTP, DNS, Memcached등이 존재한다. 반사 트래픽으로 이용되는 프로토콜 중에서 반사 트래픽의 응답크기가 높은 DNS 프로토콜과 Memcached 프로토콜을 비교분석결과, Memcached 프로토콜은 DNS 프로토콜보다 ±21% 증폭된다. 대응방안은 Memcached 프로토콜의 메모리 초기화 명령어를 사용하여 공격의 효과를 감소시킬 수 있다. 향후 연구에서는 보안에 취약한 다양한 서버들을 보안 네트워크를 통해 공유하여 원천적 차단효과를 전망할 수 있다.

Signaling Role of Adipocyte Leptin in Prostate Cell Proliferation Induced by Trichomonas vaginalis

  • Kim, Jung-Hyun;Han, Ik-Hwan;Shin, Su-Jin;Park, Sung-Yul;Chung, Hyo-Yeoung;Ryu, Jae-Sook
    • Parasites, Hosts and Diseases
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    • 제59권3호
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    • pp.235-249
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    • 2021
  • Leptin is a type of adipokine mainly produced by adipocytes and reported to be overproduced in prostate cancer. However, it is not known whether it stimulates the proliferation of prostate cells. In this study, we investigated whether benign prostatic hyperplasia epithelial cells (BPH-1 cells) infected with Trichomonas vaginalis induced the proliferation of prostate cells via a leptin signaling pathway. To investigate the effect of crosstalk between adipocyte leptin and inflamed epithelial cell in proliferation of prostate cells, adipocytes 3T3-L1 cells were incubated in conditioned medium of BPH-1 cells infected with T. vaginalis (T. vaginalis-conditioned medium, TCM), and then the adipocyte-conditioned medium (ATCM) was identified to cause proliferation of prostate cells. BPH-1 cells incubated with live T. vaginalis released pro-inflammatory cytokines, and conditioned medium of these cells caused migration of adipocytes. When prostate stromal cells and BPH-1 cells were incubated with adipocyte conditioned medium containing leptin, their growth rates increased as did expression of the leptin receptor (known as OBR) and signaling molecules such as JAK2/STAT3, Notch and survivin. Moreover, blocking the OBR reduced this proliferation and the expression of leptin signaling molecules in response to ATCM. In conclusion, our findings show that inflamed BPH-1 cells infected with T. vaginalis induce the proliferation of prostate cells through leptin-OBR signaling. Therefore, it is likely that T. vaginalis contributes to prostate enlargement in BPH via adipocyte leptin released as a result of inflammation of the prostate.

p-coumaric acid, an active ingredient of Panax ginseng, ameliolates atopic dermatitis-like skin lesions through inhibition of thymic stromal lymphopoietin in mice

  • Moon, Phil-Dong;Han, Na-Ra;Lee, Jin Soo;Kim, Hyung-Min;Jeong, Hyun-Ja
    • Journal of Ginseng Research
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    • 제45권1호
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    • pp.176-182
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    • 2021
  • Background: Atopic dermatitis (AD) is associated with chronic skin inflammatory reactions. p-coumaric acid (pCA) is an active ingredient of Panax ginseng Meyer (Araliaceae). Methods: Here, we estimated an anti-AD effect of pCA on activated mast cells, activated splenocytes, and a mouse model of AD. Cytokines levels were measured by ELISA and protein activation was analyzed by Western blotting. 2,4-dinitrofluorobenzene (DNFB) was used to induce AD-like skin lesions. Results: The treatment with pCA suppressed the productions and mRNA expressions of thymic stromal lymphopoietin (TSLP), TNF-α, IL-6, and IL-1β in HMC-1 cells. pCA downregulated the expressions of RIP2 and caspase-1, phosphorylated-(p)p38/pJNK/pERK, and pIKKβ/pIkBα/NF-κB in HMC-1 cells. pCA also decreased the productions of TSLP, TNF-α, IL-6, IL-4, and IFN-γ in the supernatant of stimulated splenic cells. Comparing to DNFB-sensitized control group, pCA-treated group alleviated pathological changes of AD-like lesions. pCA decreased the proteins and mRNA expressions levels of TSLP, IL-6, and IL-4 in the skin lesions. Caspase-1 activation was also downregulated by pCA treatment in the AD-like lesions. The serum levels of histamine, IgE, TSLP, TNF-α, IL-6, and IL-4 were suppressed following treatment with pCA. Conclusion: This study suggests that pCA has the potential to improve AD by suppressing TSLP as well as inflammatory cytokines via blocking of caspase-1/NF-κB signal cascade.