scholarly journals The Role of the Fibronectin IGD Motif in Stimulating Fibroblast Migration

2007 ◽  
Vol 282 (49) ◽  
pp. 35530-35535 ◽  
Author(s):  
Christopher J. Millard ◽  
Ian R. Ellis ◽  
Andrew R. Pickford ◽  
Ana M. Schor ◽  
Seth L. Schor ◽  
...  

The motogenic activity of migration-stimulating factor, a truncated isoform of fibronectin (FN), has been attributed to the IGD motifs present in its FN type 1 modules. The structure-function relationship of various recombinant IGD-containing FN fragments is now investigated. Their structure is assessed by solution state NMR and their motogenic ability tested on fibroblasts. Even conservative mutations in the IGD motif are inactive or have severely reduced potency, while the structure remains essentially the same. A fragment with two IGD motifs is 100 times more active than a fragment with one and up to 106 times more than synthetic tetrapeptides. The wide range of potency in different contexts is discussed in terms of cryptic FN sites and cooperativity. These results give new insight into the stimulation of fibroblast migration by IGD motifs in FN.

1983 ◽  
Vol 213 (3) ◽  
pp. 587-594 ◽  
Author(s):  
J Nandi ◽  
Z Meng-Ai ◽  
T K Ray

The distribution of free thiol groups associated with the membrane proteins of the purified pig gastric microsomal vesicles was quantified, and the relation of thiol groups to the function of the gastric (H+ + K+)-transporting ATPase system was investigated. Two different thiol-specific agents, carboxypyridine disulphide (CPDS) and N-(1-naphthyl)maleimide (NNM) were used for the study. The structure-function relationship of the membrane thiol groups was studied after modification by the probes under various conditions, relating the inhibition of the (H+ + K+)-transporting ATPase to the ATP-dependent H+ accumulation by the gastric microsomal vesicles. On the basis of the extent of stimulation of the microsomal (H+ + K+)-transporting ATPase in the presence and absence of valinomycin (val) about 85% of the vesicles were found to be intact. CPDS at 1 mM completely inhibits the valinomycin-stimulated ATPase and the associated p-nitrophenyl phosphatase with a concomitant inhibition of vesicular H+ uptake. Both the enzyme and dye-uptake activities were fully protected against CPDS inhibition when the treatment with CPDS was carried out in the presence of ATP. ATP also offered protection (about 65%) against NNM inhibition of the (H+ + K+)-transporting ATPase system and vesicular H+ uptake. Under similar conditions ATP also protected about 10 and 6 nmol of thiol groups/mg of protein respectively from CPDS and NNM reaction. Our data suggest that the thiol groups on the outer surface of the vesicles are primarily involved in gastric (H+ + K+)-transporting ATPase function. Furthermore, at least about 15% of the total microsomal thiol groups appear to be associated with the ATPase system. The data have been discussed in terms of the structure-function relationship of gastric microsomes.


2019 ◽  
Vol 58 (2) ◽  
pp. 249-259
Author(s):  
Joseph Acquisto

This essay examines a polemic between two Baudelaire critics of the 1930s, Jean Cassou and Benjamin Fondane, which centered on the relationship of poetry to progressive politics and metaphysics. I argue that a return to Baudelaire's poetry can yield insight into what seems like an impasse in Cassou and Fondane. Baudelaire provides the possibility of realigning metaphysics and politics so that poetry has the potential to become the space in which we can begin to think the two of them together, as opposed to seeing them in unresolvable tension. Or rather, the tension that Baudelaire animates between the two allows us a new way of thinking about the role of esthetics in moments of political crisis. We can in some ways see Baudelaire as responding, avant la lettre, to two of his early twentieth-century readers who correctly perceived his work as the space that breathes a new urgency into the questions of how modern poetry relates to the world from which it springs and in which it intervenes.


Author(s):  
M. G. Monika Bai ◽  
H. Vignesh Babu ◽  
V. Lakshmi ◽  
M. Rajeswara Rao

Fluorescent porous organic polymers are a unique class of materials owing to their strong aggregation induced emission, long range exciton migration and permanent porosity, thus envisioned to possess a wide range of applications (sensing, OLEDs).


Biochemistry ◽  
1982 ◽  
Vol 21 (11) ◽  
pp. 2592-2600 ◽  
Author(s):  
Yee Hsiung Chen ◽  
Jang Chyi Tai ◽  
Wan Jen Huang ◽  
Ming Zong Lai ◽  
Mien Chie Hung ◽  
...  

Hypertension ◽  
2000 ◽  
Vol 36 (suppl_1) ◽  
pp. 688-688
Author(s):  
Toshihiro Ichiki ◽  
Kotaro Takeda ◽  
Akira Takeshita

58 Recent studies suggest a crucial role of reactive oxygen species (ROS) for the signaling of Angiotensin II (Ang II) through type 1 Ang II receptor (AT1-R). However, the role of ROS in the regulation of AT1-R expression has not been explored. In this study, we examined the effect of an antioxidant on the homologous downregulation of AT1-R by Ang II. Ang II (10 -6 mol/L) decreased AT1-R mRNA with a peak suppression at 6 hours of stimulation in rat aortic vascular smooth muscle cells (VSMC). Ang II dose-dependently (10 -8 -10 -6 ) suppressed AT1-R mRNA at 6 hours of stimulation. Preincubation of VSMC with N-acetylcysteine (NAC), a potent antioxidant, almost completely inhibited the Ang II-induced downregulation of AT1-R mRNA. The effect of NAC was due to stabilization of the AT1-R mRNA that was destabilized by Ang II. Ang II did not affect the promoter activity of AT1-R gene. Diphenylene iodonium (DPI), an inhibitor of NADH/NADPH oxidase failed to inhibit the Ang II-induced AT1-R mRNA downregulation. The Ang II-induced AT1-R mRNA downregulation was also blocked by PD98059, an extracellular signal-regulated protein kinase (ERK) kinase inhibitor. Ang II-induced ERK activation was inhibited by NAC as well as PD98059 whereas DPI did not inhibit it. To confirm the role of ROS in the regulation of AT1-R mRNA expression, VSMC were stimulated with H 2 O 2 . H 2 O 2 suppressed the AT1-R mRNA expression and activated ERK. These results suggest that production of ROS and activation of ERK are critical for downregulation of AT1-R mRNA. The differential effect of NAC and DPI on the downregulation of AT1-R mRNA may suggest the presence of other sources than NADH/NADPH oxidase pathway for ROS in Ang II signaling. Generation of ROS through stimulation of AT1-R not only mediates signaling of Ang II but may play a crucial role in the adaptation process of AT1-R to the sustained stimulation of Ang II.


2013 ◽  
Author(s):  
◽  
Raksha Padaruth

This paper documents and evaluates the use of ceramics as an aesthetic architectural element in Durban from 1914-2012 with special reference to James Hall (1916-2006), Andrew Walford (b.1942) and Jane du Rand (b.1969). These artists were selected because their work demonstrates a wide range of the use of decorative tiles and mosaics as aesthetic elements in Durban architecture over a period of more than fifty years. Reference is made to the historical use of tiles and mosaics as aesthetic architectural elements in Durban from 1914-1955 in order to provide a context to an investigation and evaluation of the contribution of Hall, Walford and du Rand to the use of tiles and mosaics as an aesthetic architectural element in Durban. The paper begins by highlighting the importance of this study, discusses the role of ceramic architectural adornment and defines terminology for the purpose of this research. In addition an explanation of the research methodology used, research questions and literature review is provided. The study is contextualised through an overview of the historical background of the use of ceramics (tiles and mosaics) as an aesthetic element in architecture. The importance of the use of ceramic elements in relation to architecture, as well as the different techniques and methods of production, are highlighted and related to contemporary practice. The overview provides insight into how the use of ceramic elements in the past has influenced the approach of contemporary practice. My contribution to the use of mosaics as an aesthetic architectural element in Durban and my art practice, in the form of an installation titled passage is discussed and evaluated. The paper concludes by noting that the historical use of tiles and mosaics as aesthetic elements in architecture persists in contemporary art practice. However, the methods of tiled mosaic production and tiled mosaic techniques have been revolutionised extensively. It is evident that, the use of ceramics as an aesthetic element in Durban architecture reflects, both a strong European design influence and a distinctive local identity.


Kardiologiia ◽  
2020 ◽  
Vol 60 (4) ◽  
pp. 4-9 ◽  
Author(s):  
Yu. V. Mareev ◽  
V. Yu. Mareev

The review addressed the relationship of coronavirus disease 2019 (COVID-19) with functioning of the renin-angiotensin-aldosterone axis and the causes for unfavorable prognosis depending on patients’ age and comorbidities. The authors discussed in detail potential effects of angiotensin-converting enzyme inhibitors and angiotensin II type 1 receptor antagonists on the risk of infection and the course of COVID-2019 as well as the effect of SARS-COV2 virus on the cardiovascular system.


Author(s):  
Robert Bogue

Purpose This paper aims to illustrate the growing role robots are playing in recycling and product disassembly and provide an insight into recent research activities. Design/methodology/approach Following a short introduction, this first considers robotic waste sorting systems and then describes two systems for the disassembly of electronic products. It then provides details of some recent research activities. Finally, brief conclusions are drawn. Findings Robotic systems exploiting artificial intelligence combined with various sensing and machine vision technologies are playing a growing role in the sorting of municipal and industrial waste, prior to recycling. These are mostly based on delta robots and can achieve pick rates of 60-70 items/min and be configured to recognise and select a wide range of different materials and items from moving conveyors. Electronic waste recycling is yet to benefit significantly from robotics although a limited number of systems have been developed for product disassembly. Disassembly techniques are the topic of a concerted research effort which often involves robots and humans collaborating and sharing disassembly tasks. Originality/value This provides an insight into the present-day uses and potential future role of robots in recycling which has traditionally been a highly labour-intensive industry.


2020 ◽  
Vol 21 (6) ◽  
pp. 2099 ◽  
Author(s):  
Eugeniusz Małkowski ◽  
Krzysztof Sitko ◽  
Michał Szopiński ◽  
Żaneta Gieroń ◽  
Marta Pogrzeba ◽  
...  

Hormesis, which describes the stimulatory effect of low doses of toxic substances on growth, is a well-known phenomenon in the plant and animal kingdoms. However, the mechanisms that are involved in this phenomenon are still poorly understood. We performed preliminary studies on corn coleoptile sections, which showed a positive correlation between the stimulation of growth by Cd or Pb and an increase in the auxin and H2O2 content in the coleoptile sections. Subsequently, we grew corn seedlings in hydroponic culture and tested a wide range of Cd or Pb concentrations in order to determine hormetic growth stimulation. In these seedlings the gas exchange and the chlorophyll a fluorescence, as well as the content of chlorophyll, flavonol, auxin and hydrogen peroxide, were measured. We found that during the hormetic stimulation of growth, the response of the photosynthetic apparatus to Cd and Pb differed significantly. While the application of Cd mostly caused a decrease in various photosynthetic parameters, the application of Pb stimulated some of them. Nevertheless, we discovered that the common features of the hormetic stimulation of shoot growth by heavy metals are an increase in the auxin and flavonol content and the maintenance of hydrogen peroxide at the same level as the control plants.


Holzforschung ◽  
2020 ◽  
Vol 74 (3) ◽  
pp. 321-331 ◽  
Author(s):  
Caiping Lian ◽  
Shuqin Zhang ◽  
Xianmiao Liu ◽  
Junji Luo ◽  
Feng Yang ◽  
...  

AbstractPits are the main transverse channels of intercellular liquid transport in bamboo. Ramiform pits are a special type of simple pit with two or more branches. However, little is known about the morphology and physiological functions of ramiform pits. The anatomy of plants can provide important evidence for the role of cells. To better understand the ultrastructure and the structure-function relationship of ramiform pits, their characteristics need to be investigated. In this study, both qualitative and quantitative features of ramiform pits were studied using field-emission environmental scanning electron microscopy (FE-ESEM). The samples included the native structures and the replica structures obtained by resin castings. The results show that the ramiform pits have a diverse morphology that can be divided into main categories: type I (the primary branches) and type II (the secondary branches). The distribution of ramiform pits is different in ground parenchyma cells (GPCs) and vascular parenchyma cells (VPCs). The number, the pit aperture diameter and the pit canal length of ramiform pits in the VPCs were, respectively, greater (3-fold), larger (2–3-fold) and shorter (1.3-fold) than those in the GPCs.


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