• 제목/요약/키워드: vascular biology

검색결과 535건 처리시간 0.027초

Arctium tomentosum (Asteraceae): A new report of a native genus in the flora of Mongolia

  • JAVZANDOLGOR, Chuluunbat;BAASANMUNKH, Shukherdorj;TSEGMED, Zagarjav;OYUNTSETSEG, Batlai;GUNDEGMAA, Vanjil;CHOI, Hyeok Jae
    • 식물분류학회지
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    • 제51권4호
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    • pp.391-394
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    • 2021
  • Arctium tomentosum Mill. (Asteraceae), from Ulaanbaatar in the Khentei phytogeographical region of Mongolia, is recognized here as a new genus and species of the flora of Mongolia. Arctium differs from other genera of Asteraceae by the hooked apex of the involucral bracts. While A. tomentosum is most similar to A. lappa, it is easily distinguished by the glandular hairs of the corolla limb and the widened inner involucral bracts. Taxonomic notes, a description of the morphology, detailed photos, habitat information, the phenology and a distribution map of A. tomentosum are provided.

Intravenous administration of piceatannol, an arginase inhibitor, improves endothelial dysfunction in aged mice

  • Nguyen, Minh Cong;Ryoo, Sungwoo
    • The Korean Journal of Physiology and Pharmacology
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    • 제21권1호
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    • pp.83-90
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    • 2017
  • Advanced age is one of the risk factors for vascular diseases that are mainly caused by impaired nitric oxide (NO) production. It has been demonstrated that endothelial arginase constrains the activity of endothelial nitric oxide synthase (eNOS) and limits NO generation. Hence, arginase inhibition is suggested to be vasoprotective in aging. In this study, we examined the effects of intravenous injection of Piceatannol, an arginase inhibitor, on aged mice. Our results show that Piceatannol administration reduced the blood pressure in aged mice by inhibiting arginase activity, which was associated with NO production and reactive oxygen species generation. In addition, Piceatannol administration recovered $Ca^{2+}$/calmodulin-dependent protein kinase II phosphorylation, eNOS phosphorylation and eNOS dimer stability in the aged mice. The improved NO signaling was shown to be effective in attenuating the phenylephrine-dependent contractile response and in enhancing the acetylcholine-dependent vasorelaxation response in aortic rings from the aged mice. These data suggest Piceatannol as a potential treatment for vascular disease.

Thrombin inhibits HMGB1-mediated proinflammatory signaling responses when endothelial protein C receptor is occupied by its natural ligand

  • Bae, Jong-Sup;Rezaie, Alireza R.
    • BMB Reports
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    • 제46권11호
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    • pp.544-549
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    • 2013
  • High mobility group box 1 (HMGB1) is involved in the pathogenesis of vascular diseases. Unlike activated protein C (APC), the activation of PAR-1 by thrombin is known to elicit proinflammatory responses. To determine whether the occupancy of EPCR by the Gla-domain of APC is responsible for the PAR-1-dependent antiinflammatory activity of the protease, we pretreated HUVECs with the PC zymogen and then activated PAR-1 with thrombin. It was found that thrombin downregulates the HMGB1-mediated induction of both TNF-${\alpha}$ and IL-6 and inhibits the activation of both p38 MAPK and NF-${\kappa}B$ in HUVECs pretreated with PC. Furthermore, thrombin inhibited HMGB1-mediated hyperpermeability and leukocyte adhesion/migration by inhibiting the expression of cell adhesion molecules in HUVECs if EPCR was occupied. Collectively, these results suggest the concept that thrombin can initiate proinflammatory responses in vascular endothelial cells through the activation of PAR-1 may not hold true for normal vessels expressing EPCR under in vivo conditions.

Porphyromonas Gingivalis Lipopolysaccharide Increases Monocyte Adhesion to Microvascular Endothelium by Induction of Adhesion Molecules

  • Kim, Su-Ryun;Park, Hyun-Joo;Bae, Soo-Kyung;Park, Ji-Hyun;Kim, Hyo-Sun;Koo, Tae-Hyeon;Bae, Moon-Kyoung
    • International Journal of Oral Biology
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    • 제33권4호
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    • pp.149-154
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    • 2008
  • Porphyromonas gingivalis, a major periodontal pathogen, has been implicated in the initiation and progression of periodontal disease. Endothelial dysfunction (Editor note: Aberrant and dysfunction are somewhat redundant. The authors may want to choose one or the other.) contributes to chronic periodontal inflammation. Using cDNA-representational difference analysis, we found that P.gingivalis lipopolysaccharide differentially induces a number of genes in human microvascular endothelial cells. Among these upregulated genes, we focused on intercellular adhesion molecule-1 (VCAM-1), which is crucial for leukocyte recruitment during vascular inflammation. P. gingivalis LPS significantly increased the expression of vascular cell adhesion molecule-1 (VCAM-1) as well as ICAM-1. Promoter assays revealed that the transcription of these cell adhesion molecules was mainly regulated by nuclear factor-${\kappa}B$ (NF-${\kappa}B$) in endothelial cells. Furthermore, P. gingivalis LPS significantly increased leukocyte adhesiveness to microvascular endothelial cells and to aortic endothelium. Taken together, our results demonstrate that P. gingivalis LPS activates microvascular endothelial cells through NF-${\kappa}B$-dependent expression of cell adhesion molecules.

Origin of Callus and Vascular Cambium in Debarked Stem of Robinia pseudoacacia

  • Soh, Woong-Young
    • Journal of Plant Biology
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    • 제37권3호
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    • pp.317-323
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    • 1994
  • The calluses formed on the surface of a quarter-girdled Robinia pseudoacacia stems have been shown to originate from immature xylem cells and preexisting cambial cells. The cellus is not only formed by periclinal and anticlinal divisions of radial cells, but also axial cells. In tangential view, the callus at initial stage showed heterogeneous structure composed of long and short cells and then homogeneous one with short cells. Some cells of homogeneous structure in middle region of callus at early stage is later elongated and others mainly divided in trasverse plane. In the result the homogeneous structure becomes into a heterogeneous one. Subsequently, the long cells in heterogeneous structures elongated further and became fusifrom initials, and the short cells divided transversely became ray initials. The appearence of homogeneous and heterogeneous structure in the callus on debarked stem without organ elongation is almost similar to that of the structure in the procambium of young stem which is elongating extensively. Eventually, the ontogeny of vascular cambium in wound callus resembles that of a young stem grown normally, although the debarked stem does not grow in length but in girth and the young stem elongates activity. These findings mean that the active intrusive growth of short procambial cells occurs during the differentiation of fusiform cambial cells.

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한국에서 채집된 미키 박사 표본에 대한 분류학적 검토 (Taxonomic Notes on the Dr. Miki's Specimens Collected from Korea)

  • 신현철
    • 식물분류학회지
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    • 제36권1호
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    • pp.41-52
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    • 2006
  • 일본 오사카 자연사박물관에는 미키 박사의 수생관속식물 표본 3,600 여점이 소장되어 있다. 그 중에서 우리나라에서 채집된 표본은 104점이었고, 이를 재동정한 결과 48종류인 것으로 밝혀졌다. 이는 미키 박사와 장형두를 비롯한 14인에 의하여 1920년대에 주로 채집된 것이다. 매화마름 (Ranunculus kadzusensis), 솔잎가래 (Potamogeton pectinatus), 애기거머리말 (Zostera japonica), Ruppia truncatifolia(국명 없음), 그리고 통발속 (Utricularia species)과 같이 국내에서 멸종 위기 내지 희귀종인 수생관속식물에 대하여 분류학적 검토를 하였다. 또한, 통발 속의 Utricularia ochroleuca Hartm. 와 U. tenuicaulis Miki, Blyxa leiosperma Koidz., Najas japonica Nakai, 그리고 Rotala leptopetala Koehne 등 5종은 우리나라 미기록종이다.

The Bioinformatics and Molecular Biology Approaches for Vascular Cell Signaling by Advanced Glycation Endproducts Receptor and Small Ubiquitin-Related Modifier

  • Kim, June Hyun
    • Interdisciplinary Bio Central
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    • 제4권4호
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    • pp.12.1-12.6
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    • 2012
  • The advanced glycation endproducts receptor (AGE-R) is a signal transduction receptor for multiligand such as S100b and AGEs. S100b has been demonstrated to activate various cells with important links to atherosclerosis initiation and progression including endothelial cells, and smooth muscle cells via AGE-R, triggering activation of multiple signaling cascades through its cytoplasmic domain. Many studies have suggested AGE-R might even participate in the cardiovascular complications involved in the pathogenesis of type I diabetes. Recently, Small Ubiquitin-Related Modifier 1 (SURM-1 also known as SUMO-1) has been recognized as a protein that plays an important role in cellular post-translational modifications in a variety of cellular processes, such as transport, transcriptional, apoptosis and stability. Computer Database search with SUMOplot Analysis program identified the five potential SURMylation sites in human AGE-R: K43, K44, K123, and K273 reside within the extracellular domain of AGE-R, and lastly K374 resides with the cytosolic domain of AGE-R. The presence of the consensus yKXE motif in the AGE-R strongly suggests that AGE-R may be regulated by SURMylation process. To test this, we decided to determine if AGE-R is SURMylated in living vascular cell system. S100b-stimulated murine aortic vascular smooth muscle cells were used for western blot analysis with relevant antibodies. Taken together, bioinformatics database search and molecular biological approaches suggested AGE-R is SURMylated in living cardiovascular cell system. Whilst SURMylation and AGE-R undoubtedly plays an important role in the cardiovascular biology, it remains unclear as to the exact nature of this contribution under both physiological and pathological conditions.

탐진강 하구역 일대(강진군)의 관속식물상 (Floristic Study of Tamjin River Estuary in Gangjin-gun, Korea)

  • 장현도;임효선;한세희;오아미;오병운;양선규
    • 한국환경과학회지
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    • 제29권6호
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    • pp.579-603
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    • 2020
  • In order to provide fundamental information about the floristic composition of the area along with an assessment of the environmental impact, a floristic study of the vascular plants in the Tamjin River estuary in Gangjin-gun was conducted for a total of nine days, in the period from June 2014 to September 2014. We found that the vascular plants in this region comprised 424 taxa belong to 102 families, 281 genera, 390 species, 5 subspecies, 26 varieties, and 3 forma. Five taxa of Korean endemic plants including Weigela subsessilis (Nakai) L.H.Bailey, Lespedeza maximowiczii var. tricolor (Nakai) Nakai, and Clematis trichotoma Nakai were collected. Two least concern (LC) taxa of rare plants (as designated by the Korea Forest Service) were collected: Hydrocharis dubia (Blume) Backer and Platycladus orientalis (L.) Franco. Ten the floristic regional indicator taxa from the third to the fifth grade were identified: two taxa belonged to grade IV, and eight taxa belonged to grade III. Twenty-four taxa of salt-tolerant plants, including Artemisia fukudo Makino, Carex rugulosa Kuk., and Suaeda glauca (Bunge) Bunge, as well as 44 taxa of aquatic plants, including Najas marina L., Nuphar oguraensis Miki, and Nymphoides indica (L.) Kuntze, were investigated in this region. Fifty-nine taxa of naturalized plants were recorded, among which the following six taxa were plants that caused ecosystem disturbance: Ambrosia artemisiifolia L., Humulus scandens (Lour.) Merr., Lactuca scariola L., Rumex acetosella L., Solidago altissima L., and Symphyotrichum pilosum (Willd.) G.L.Nesom.

Protease-Activated Receptor 2 Activation Inhibits N-Type Ca2+ Currents in Rat Peripheral Sympathetic Neurons

  • Kim, Young-Hwan;Ahn, Duck-Sun;Kim, Myeong Ok;Joeng, Ji-Hyun;Chung, Seungsoo
    • Molecules and Cells
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    • 제37권11호
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    • pp.804-811
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    • 2014
  • The protease-activated receptor (PAR)-2 is highly expressed in endothelial cells and vascular smooth muscle cells. It plays a crucial role in regulating blood pressure via the modulation of peripheral vascular tone. Although several mechanisms have been suggested to explain PAR-2-induced hypotension, the precise mechanism remains to be elucidated. To investigate this possibility, we investigated the effects of PAR-2 activation on N-type $Ca^{2+}$ currents ($I_{Ca-N}$) in isolated neurons of the celiac ganglion (CG), which is involved in the sympathetic regulation of mesenteric artery vascular tone. PAR-2 agonists irreversibly diminished voltage-gated $Ca^{2+}$ currents ($I_{Ca}$), measured using the patch-clamp method, in rat CG neurons, whereas thrombin had little effect on $I_{Ca}$. This PAR-2-induced inhibition was almost completely prevented by ${\omega}$-CgTx, a potent N-type $Ca^{2+}$ channel blocker, suggesting the involvement of N-type $Ca^{2+}$ channels in PAR-2-induced inhibition. In addition, PAR-2 agonists inhibited $I_{Ca-N}$ in a voltage-independent manner in rat CG neurons. Moreover, PAR-2 agonists reduced action potential (AP) firing frequency as measured using the current-clamp method in rat CG neurons. This inhibition of AP firing induced by PAR-2 agonists was almost completely prevented by ${\omega}$-CgTx, indicating that PAR-2 activation may regulate the membrane excitability of peripheral sympathetic neurons through modulation of N-type $Ca^{2+}$ channels. In conclusion, the present findings demonstrate that the activation of PAR-2 suppresses peripheral sympathetic outflow by modulating N-type $Ca^{2+}$ channel activity, which appears to be involved in PAR-2-induced hypotension, in peripheral sympathetic nerve terminals.

외나로도의 관속식물상 (Flora of vascular plants on Oenarodo Island)

  • 황승현;라은화;이진웅;안진갑
    • 식물분류학회지
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    • 제49권2호
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    • pp.179-197
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    • 2019
  • 전라남도 고흥군에 위치하는 외나로도의 관속식물상을 조사하고 분포가 확인된 주요식물에 대해 논의하였다. 2015년 3월부터 2017년 10월까지 3년 동안 총 21회의 현지조사에서 확보된 표본에 근거하여 관속식물목록을 작성하였고, 국립생물자원관 표본관(KB)과 대전대 생물학과 표본실(TUT)에 수장하였다. 본 조사에서 생육이 확인된 관속식물은 122과 364속 538종 6아종 41변종 2품종의 총 587분류군이다. 멸종위기야생생물로는 혹난초, 지네발란, 대흥란, 석곡 4분류군을 확인하였다. 한반도고유종은 변산바람꽃, 해변싸리, 거제물봉선 등 14분류군이었고, 식물구계학적 특정식물로는 V등급 4분류군, IV등급 4분류군, III등급 47분류군, II등급 18분류군, I등급 64분류군으로 총 137분류군이 조사되었다. 적색식물목록종으로는 위급종(critically endangered) 꽃꿩의다리를 포함하여16분류군을 확인하였다. 귀화식물로는 가시상추, 물참새피 등 46분류군이 조사되었다.