• Title/Summary/Keyword: vascular biology

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Leaf Anatomy of Parkia clappertoniana Keay(Mimosaceae)

  • Oladele, F.A.;Fawole, M.O.;Bhat, R.B.
    • Journal of Plant Biology
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    • v.28 no.1
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    • pp.21-28
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    • 1985
  • The bipinnate-compound leaf of Parkia clappertoniana has prominent, long petiole with a pulvinal base. The pulvinus has wood, periderm, lenticels and extensive cortical layer. Its vascular bundles are elongated with alternating rays. The vascular bundles of the petiole, rachis and veins are oval, with conspicuous bundle caps. Stomatal complex is predominantly paracytic with occasional occurrence of anomocytic stomata near the midrib. The oval stomata have conspicuous stomatal ledges. Trichomes are unicellular, acicular and restricted to the rachis, petiole and pinnule mid-ribs and margin. Ecological and taxonomic significance of features is discussed.

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The Flora of Jangsanbong (장산봉(부산)의 식물상)

  • Lee, Jung-Hoon;Moon, Sung-Gi
    • Journal of Environmental Science International
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    • v.16 no.8
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    • pp.881-889
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    • 2007
  • The flora of vascular plants in Jangsanbong located at Busan Metropolitan City was investigated from April 2003 to April 2004. Vascular plants in the surveyed area were 254 taxa that belonged to 78 families, 175 genera, 218 species, 34 varieties, and 2 forma. Among them, 20 taxa of evergreen broad trees, 31 taxa of naturalized plants were identified, and especially Rubus trifidus was first recorded in Busan. In the upper part of a circular road dominant species was Pinus thunbergii. In the lower part of a circular road and the coastal area, dominant species were Platycarya strobilacea, Clerodendron trichotomum, Euscaphis japonica, Quercus aliena, Quercus dentata, Mallotus japonicus, which distribute mainly in the subtropical and temperate zone. In the surveyed area, the canopy consistsed of tall trees, Pinus thunbergii, and the understratum were trees such as Eurya japonica, Ficus erecta, Ligustrum japonicum, Prunus sargentii, and Celtis sinensis var. japonica.

MicroRNAs as critical regulators of the endothelial to mesenchymal transition in vascular biology

  • Kim, Jongmin
    • BMB Reports
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    • v.51 no.2
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    • pp.65-72
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    • 2018
  • The endothelial to mesenchymal transition (EndMT) is a newly recognized, fundamental biological process involved in development and tissue regeneration, as well as pathological processes such as the complications of diabetes, fibrosis and pulmonary arterial hypertension. The EndMT process is tightly controlled by diverse signaling networks, similar to the epithelial to mesenchymal transition. Accumulating evidence suggests that microRNAs (miRNAs) are key regulators of this network, with the capacity to target multiple messenger RNAs involved in the EndMT process as well as in the regulation of disease progression. Thus, it is highly important to understand the molecular basis of miRNA control of EndMT. This review highlights the current fund of knowledge regarding the known links between miRNAs and the EndMT process, with a focus on the mechanism that regulates associated signaling pathways and discusses the potential for the EndMT as a therapeutic target to treat many diseases.

Vascular Endothelial Growth Factor Upregulates Follistatin in Human Umbilical Vein Endothelial Cells

  • Oh, In-Suk;Kim, Hwan-Gyu
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.9 no.3
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    • pp.201-206
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    • 2004
  • Vascular endothelial growth factor (VEGF), plays a key role in angiogenesis. Many endogenous factors can affect angiogenesis in endothelial cells. VEGF is known to be a strong migration, sprouting, survival, and proliferation factor for endothelial cells during angiogenesis in endothelial cells. Searching for novel genes involved in VEGF signaling during angiogenesis, we carried out differential display polymerase chain reaction on RNA from VEGF-stimulated human umbilical vein endothelial cells (HUVECs). In this study, follistatin (FS) differentially expressed in VEGF-treated HUVECs, compared with controls. Addition of VEGF (10ng/L) produced an approximately 11.8-fold increase of FS mRNA. F5 or VEGF produced approximately 1.8- or 2.9-fold increases, respectively, in matrix metalloproteinase-2 (MMP-2) secretion for 12h, compared to the addition of a control buffer. We suggest that VEGF may affect the angiogenic effect of HUVECs, through a combination of the direct effects of VEGF itself, and the indirect effects mediated via induction of FS in vitro.

Baicalein and wogonin inhibit collagen deposition in SHR and WKY cardiac fibroblast cultures

  • Kong, Ebenezer K.C.;Huang, Yu;Sanderson, John E.;Chan, Kar-Bik;Yu, Shan;Yu, Cheuk-Man
    • BMB Reports
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    • v.43 no.4
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    • pp.297-303
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    • 2010
  • In order to demonstrate the potential therapeutic effect of two flavonoids, Baicalein and Wogonin, on suppression of pathological myocardial fibrosis in hypertension, we investigated their in vitro effects on collagen expression in primary cultured cardiac fibroblasts isolated from neonatal normotensive (WKY) and hypertensive (SHR) rats. Our results showed that over-expression of collagen mRNA and protein induced in cardiac fibroblasts by angiotensin (AngII) could be attenuated significantly by both flavonoids at an optimal dosage ($30\;{\mu}M$; P < 0.01). Results of immunoblots showed that expression of 12-LO level, p-ERK/ ERK ratio and MMP-9 in AngII-stimulated SHR cardiac fibroblasts were significantly down-regulated by both flavonoids. Our results show that both Baicalein and Wogonin can suppress collagen deposition in AngII-stimulated SHR and WKY cardiac fibroblasts.

The bimodal regulation of vascular function by superoxide anion: role of endothelium

  • Demirci, Buket;McKeown, Pascal P.;Bayraktutan DVM, Ulvi
    • BMB Reports
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    • v.41 no.3
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    • pp.223-229
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    • 2008
  • Reactive oxygen species (ROS) are implicated in vascular homeostasis. This study investigated whether ${O_2}^{\cdot^-}$, the foundation molecule of all ROS, regulates vasomotor function. Hence, vascular reactivity was measured using rat thoracic aortas exposed to an ${O_2}^{\cdot^-}$ generator (pyrogallol) which dose-dependently regulated both $\alpha$-adrenergic agonist-mediated contractility to phenylephrine and endothelium-dependent relaxations to acetylcholine. Pyrogallol improved and attenuated responses to acetylcholine at its lower (10 nM - 1 ${\mu}M$) and higher (10 - 100 ${\mu}M$) concentrations, respectively while producing the inverse effects with phenylephrine. The endothelial inactivation by L-NAME abolished acetylcholine-induced vasodilatations but increased phenylephrine and KCl-induced vasoconstrictions regardless of the pyrogallol dose used. Relaxant responses to sodium nitroprusside, a nitric oxide donor, were not affected by pyrogallol. Other ROS i.e. peroxynitrite and $H_2O_2$ that may be produced during experiments did not alter vascular functions. These findings suggest that the nature of ${O_2}^{\cdot^-}$-evoked vascular function is determined by its local concentration and the presence of a functional endothelium.

Post-Transcriptional Control of Tropoelastin in Aortic Smooth Muscle Cells Affects Aortic Dissection Onset

  • Qi, You-Fei;Shu, Chang;Xiao, Zhan-Xiang;Luo, Ming-Yao;Fang, Kun;Guo, Yuan-Yuan;Zhang, Wen-Bo;Yue, Jie
    • Molecules and Cells
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    • v.41 no.3
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    • pp.198-206
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    • 2018
  • Aortic dissection (AD) is a catastrophic disease with high mortality and morbidity, characterized with fragmentation of elastin and loss of smooth muscle cells. Although AD has been largely attributable to polymorphisms defect in the elastin-coding gene, tropoelastin (TE), other undermined factors also appear to play roles in AD onset. Here, we investigated the effects of post-transcriptional control of TE by microRNAs (miRNAs) on elastin levels in aortic smooth muscle cells (ASMC). We found that miR-144-3p is a miRNA that targets TE mRNA in both human and mouse. Bioinformatics analyses and dual luciferase reporter assay showed that miR-144-3p inhibited protein translation of TE, through binding to the 3'-UTR of the TE mRNA. Interestingly, higher miR-144-3p levels and lower TE were detected in the ASMC obtained from AD patients, compared to those from non-AD controls. In a mouse model for human AD, infusion of adeno-associated viruses (serotype 6) carrying antisense for miR-144-3p (asmiR-144-3p) under CAG promoter significantly reduced the incidence and severity of AD, seemingly through enhancement of TE levels in ASMC. Thus, our data suggest an essential role of miR-144-3p on the pathogenesis of AD.

Oleanolic Acids Inhibit Vascular Endothelial Growth Factor Receptor 2 Signaling in Endothelial Cells: Implication for Anti-Angiogenic Therapy

  • Lee, Da-Hye;Lee, Jungsul;Jeon, Jongwook;Kim, Kyung-Jin;Yun, Jang-Hyuk;Jeong, Han-Seok;Lee, Eun Hui;Koh, Young Jun;Cho, Chung-Hyun
    • Molecules and Cells
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    • v.41 no.8
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    • pp.771-780
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    • 2018
  • Angiogenesis must be precisely controlled because uncontrolled angiogenesis is involved in aggravation of disease symptoms. Vascular endothelial growth factor (VEGF)/VEGF receptor 2 (VEGFR-2) signaling is a key pathway leading to angiogenic responses in vascular endothelial cells (ECs). Therefore, targeting VEGF/VEGFR-2 signaling may be effective at modulating angiogenesis to alleviate various disease symptoms. Oleanolic acid was verified as a VEGFR-2 binding chemical from anticancer herbs with similar binding affinity as a reference drug in the Protein Data Bank (PDB) entry 3CJG of model A coordination. Oleanolic acid effectively inhibited VEGF-induced VEGFR-2 activation and angiogenesis in HUVECs without cytotoxicity. We also verified that oleanolic acid inhibits in vivo angiogenesis during the development and the course of the retinopathy of prematurity (ROP) model in the mouse retina. Taken together, our results suggest a potential therapeutic benefit of oleanolic acid for inhibiting angiogenesis in proangiogenic diseases, including retinopathy.

Studies on the concentrations of hormones and the structure of uterine endometrium during the implantation period in rats (흰쥐 수정란 착상시기에 있어서의 호르몬 농도의 변화와 자궁내막의 구조에 관한 연구)

  • Yoon, Mi-Chung;Sohn, Seong-Hyang;Kim, Chang-Mee;Choe, Rim-Soon
    • Applied Microscopy
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    • v.23 no.1
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    • pp.77-90
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    • 1993
  • The mechanism by which blastocysts implant to uterine endometrium has not been clearly understood. In the present study, the following question was investigated: how are hormonal levels changed and how is uterine endometrium morphologically changed? Results obtained are as follows: Concentrations of serum estradiol and progesterone were significantly increased on day 4 and 5 of pregnancy. Uterine concentrations of PGE and $PGE_{2a}$ were sharply increased on day 1 and maintained similar concentrations thereafter, reaching the maximum on day 5. Both prostaglandins (PGs) concentrations were gradually decreased thereafter. Furthermore, concentrations of PGs in implant sites were greater than those in non-implant sites. PBR (pontamine blue reaction) in uterine endometrium was positive on day 6 of pregnancy, indicating that vascular permeability was increased. Edema and changes in structure of cell components were pronounced in stroma where PBR was developed. Moreover, these were more prominent in implant sites than non-implant sites. These results suggest that uterine PGs as well as steroid hormones increase during implantation in rats and these hormones might be involved in the process of implantation by modulating vascular permeability and the fine structures of uterine endometrial cells.

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