34 research outputs found
Display of Cell Surface Sites for Fibronectin Assembly Is Modulated by Cell Adherence to 1F3 and C-Terminal Modules of Fibronectin
BACKGROUND: Fibronectin-null cells assemble soluble fibronectin shortly after adherence to a substrate coated with intact fibronectin but not when adherent to the cell-binding domain of fibronectin (modules (7)F3-(10)F3). Interactions of adherent cells with regions of adsorbed fibronectin other than modules (7)F3-(10)F3, therefore, are required for early display of the cell surface sites that initiate and direct fibronectin assembly. METHODOLOGY/PRINCIPAL FINDINGS: To identify these regions, coatings of proteolytically derived or recombinant pieces of fibronectin containing modules in addition to (7)F3-(10)F3 were tested for effects on fibronectin assembly by adherent fibronectin-null fibroblasts. Pieces as large as one comprising modules (2)F3-(14)F3, which include the heparin-binding and cell adhesion domains, were not effective in supporting fibronectin assembly. Addition of module (1)F3 or the C-terminal modules to modules (2)F3-(14)F3 resulted in some activity, and addition of both (1)F3 and the C-terminal modules resulted in a construct, (1)F3-C, that best mimicked the activity of a coating of intact fibronectin. Constructs (1)F3-C V0, (1)F3-C V64, and (1)F3-C Delta(V(15)F3(10)F1) were all able to support fibronectin assembly, suggesting that (1)F3 through (11)F1 and/or (12)F1 were important for activity. Coatings in which the active parts of (1)F3-C were present in different proteins were much less active than intact (1)F3-C. CONCLUSIONS: These results suggest that (1)F3 acts together with C-terminal modules to induce display of fibronectin assembly sites on adherent cells
Anatomical study of the female reproductive system and bacteriome of Diaphorina citri Kuwayama, (Insecta: Hemiptera, Liviidae) using micro-computed tomography
Huanglongbing (HLB) (citrus greening disease) is one of the most serious bacterial diseases of citrus. It
is caused by (1) Candidatus Liberibacter africanus, transmitted by Trioza erytreae and (2) C.L. asiaticus
and C.L. americanus, transmitted by Diaphorina citri. As part of a multidisciplinary project on D. citri
(www.citrusgreening.org), we made a detailed study, using micro-computed tomography, of the female
abdominal terminalia, reproductive system (ovaries, accessory glands, spermatheca, colleterial (=
cement) gland, connecting ducts, and ovipositor) and bacteriome, which we present here. New terms
and structures are introduced and described, particularly concerning the spermatheca, ovipositor and
bacteriome. The quality of images and bacteriome reconstructions are comparable, or clearer, than
those previously published using a synchrotron or fuorescence in situ hybridisation (FISH). This study:
reviews knowledge of the female reproductive system and bacteriome organ in D. citri; represents
the frst detailed morphological study of D. citri to use micro-CT; and extensively revises existing
morphological information relevant to psylloids, hemipterans and insects in general. High quality
images and supplementary videos represent a signifcant advance in knowledge of psylloid anatomy
and are useful tools for future research and as educational aids.Kansas State University (KSU)
S15192.01University of Granada, USDA-NIFA
S15192.01
2014-70016-2302
Plasma and cellular fibronectin: distinct and independent functions during tissue repair
Fibronectin (FN) is a ubiquitous extracellular matrix (ECM) glycoprotein that plays vital roles during tissue repair. The plasma form of FN circulates in the blood, and upon tissue injury, is incorporated into fibrin clots to exert effects on platelet function and to mediate hemostasis. Cellular FN is then synthesized and assembled by cells as they migrate into the clot to reconstitute damaged tissue. The assembly of FN into a complex three-dimensional matrix during physiological repair plays a key role not only as a structural scaffold, but also as a regulator of cell function during this stage of tissue repair. FN fibrillogenesis is a complex, stepwise process that is strictly regulated by a multitude of factors. During fibrosis, there is excessive deposition of ECM, of which FN is one of the major components. Aberrant FN-matrix assembly is a major contributing factor to the switch from normal tissue repair to misregulated fibrosis. Understanding the mechanisms involved in FN assembly and how these interplay with cellular, fibrotic and immune responses may reveal targets for the future development of therapies to regulate aberrant tissue-repair processes
Use Of Aluminum Phosphate, Polyphosphate And Metaphosphate Particles In Paper Coating Applications
Provided herein are coating compositions for paper comprising aluminum phosphate, aluminum metaphosphate, aluminum orthophosphate and/or aluminum polyphosphate pigments. Methods of making and using the compositions are described.CA2752120 (A1)D21H19/38CA20102752120D21H19/3
Age, muscle fatigue, and walking endurance in pre-menopausal women
Aging is associated with loss of endurance; however, aging is also associated with decreased fatigue during maximal isometric contractions. The aims of this study were to examine the relationship between age and walking endurance (WE) and maximal isometric fatigue (MIF) and to determine which metabolic/fitness components explain the expected age effects on WE and MIF. Subjects were 96 pre-menopausal women. Oxygen uptake (walking economy) was assessed during a 3-mph walk; aerobic capacity and WE by progressive treadmill test; knee extension strength by isometric contractions, MIF during a 90-s isometric plantar flexion (muscle metabolism measured by 31P MRS). Age was related to increased walking economy (low VO2, r = −0.19, P 0.80). In premenopausal women, age is related to WE and MIF. In addition, these results support the hypothesis that age-related increases in metabolic economy may decrease MIF. However, decreased muscle strength and oxidative capacity are related to WE