1,276 research outputs found
Efficacy of erythropoietin-pretreated mesenchymal stem cells in murine burn wound healing: possible in vivo transdifferentiation into keratinocytes
Background: Stem cells have shown promising potential to treat burn wounds. Erythropoietin was capable of promoting in vitro transdifferentiation of mesenchymal stem cells (MSCs). The aim of the study was to investigate possible role of erythropoietin-pretreated mesenchymal stem cells (EPOa/MSCs) in burn wounds healing and to evaluate its in vivo differentiation into keratinocytes. Materials and methods: Forty rats were utilised in this study divided into four groups (n = 10 for each). Control group (I), burn group (II), burn + MSCs, group (III), burn + EPOa/MSCs. 1 × 106 cells were injected locally for each 1 cm2 of burn areas. Burn areas were followed-up morphologically. After 21 days of the experiment, the rats were euthanised, skin specimens were assessed biochemically, histologically and immunohistochemically. Results: EPOa/MSCs enhanced significantly (p < 0.05) burn wound vimentin gene expression and level of interleukin (IL)-10 while decreased IL-1 and COX2 as compared to the burn group. Histologically, EPOa/MSCs improved epithelialisation despite stem cells’ differentiation into keratinocytes was rarely detected by PKH26 red fluorescence. EPOa/MSCs promoted angiogenesis as detected by significant increase in VEGF and PDGF immunoexpression as compared to burn group. Conclusions: EPOa/MSCs may improve burn wound healing, probably through anti-inflammatory, immunomodulatory and angiogenic action. However, in vivo transdifferentiation into keratinocytes was rarely detected
Biosynthesis and assembly of pectin and glucuronoarabinoxylan in plants
Nascent pectin and glucuronarabinoxylan (GAX), synthesized in vitro by membrane-bound enzymes from etiolated pea (Pisum sativum L.) epicotyls, were found to bind to pea xyloglucan in a pH-dependent manner. The binding was maximum at low pH (3-4), and decreased to almost zero at pH 6. The binding seemed to occur instantaneously, to be non-covalent, and to require both terminal fucose residues of xyloglucan, in addition to the non-reduced acid residues of GAX and pectin. Removal by protease of the proteins attached to nascent pectin and GAX, greatly reduced the maximum binding and abolished the pH-dependence. The proteins involved seem to have approximate molecular weights of 14 and 94 kDa.
The pH-dependent binding of nascent pectin and GAX is not completely specific to xyloglucan, since some binding occurred to a range of other matrix polysaccharides, though at a lower level than to pea xyloglucan.
Newly-deposited pectin was extracted from peas that were incubated with radioactively labelled sucrose. It was shown to behave in a similar manner as nascent pectin, exhibiting the same pH-dependent binding pattern to xyloglucan. Protease treatment of pectin decreased the binding, indicating the possible presence of proteins attached to pectin in the cell wall, and revealing the role of those proteins in the interaction of pectin with other matrix polysaccharides, particularly xyloglucan.
The pH-dependence of the binding suggests a functional interaction with the mechanisms that control growth, since the wall pH decreases when elongation growth is initiated. The proteins involved would play a significant role in cell-wall assembly and cell-wall elongation
Protocols and pitfalls in obtaining fatty acid-binding proteins for biophysical studies of ligand-protein and protein-protein interactions
Adipocyte fatty acid-binding protein (AFABP: FABP4) is a member of the intracellular lipid-binding protein family that is thought to target long-chain fatty acids to nuclear receptors such as peroxisome proliferatoractivated receptor gamma (PPARÎł), which in turn plays roles in insulin resistance and obesity. A molecular understanding of AFABP function requires robust isolation of the protein in liganded and free forms as well as characterization of its oligomerization state(s) under physiological conditions. We report development of a protocol to optimize the production of members of this protein family in pure form, including removal of their bound lipids by mixing with hydrophobically functionalized hydroxypropyl dextran beads and validation by two-dimensional NMR spectroscopy. The formation of self-associated or covalently bonded protein dimers was evaluated critically using gel filtration chromatography, revealing conditions that promote or prevent formation of disulfide-linked homodimers. The resulting scheme provides a solid foundation for future investigations of AFABP interactions with key ligand and protein partners involved in lipid metabolism
Efficiency of selenium in attenuating epididymal histopathological changes in hypercholesterolaemic adult rat
Background: Studies on sperm maturation, epididymal histology, or epididymal tubule physiology are significant parts in reproductive researches. The present study was aimed to evaluate the effect of induced hypercholesterolaemia on the epididymis of adult albino rats and to clarify the possible protective role of selenium.
Materials and methods: Forty adult albino Wistar rats were divided into four groups; untreated control group (group I), sham control (group II), group with induced hypercholesterolaemia (group III), group with induced hypercholesterolaemia treated with selenium 0.25 mg/kg/day (group IV).
Results: Histological and ultrastructural examination of the epididymal epithelial cells of hypercholesterolaemic rats (group III) showed loss of cilia with many vacuolations, fatty degenerative changes and increased collagen fibres. Morphometrically significant increase (p < 0.0001) in the per cent area of collagen fibres with no significant change in the optical density of periodic acid Schiff reaction (p > 0.05). Selenium treated group (group IV) produced marked improvement in histological, ultrastructural and morphometric results as compared with group III.
Conclusions: It could be concluded that hypercholesterolaemia produced deleterious effects to the epididymis and selenium could attenuate these effects
EFFECT OF SUBSTITUTION OF WHEAT FLOUR WITH QUINOA FLOUR ON QUALITY OF PAN BREAD AND BISCUIT
This study was carried out to investigate the effect of partial substitution (5, 10 and15%) of wheat flour (72% ext.) by whole meal quinoa flour (QF) on quality parameter of pan bread. QF contained the highest percentage of protein, Lipids, ash and crude fiber. Also, QF contained the highest amount of essential amino acids such as (threonine, methionine, lysine and histidine). From the results, it could be seen that, water absorption and degree of softening increased by increasing the substitution levels, but stability, resistance to extensions and energy of dough decreased. The addition of QF adversely affected on the specific volume of pan bread. The lightness (L*) and yellowness (b*) of pan bread decreased, but redness (a*) increased gradually by increasing QF. Evaluation of the organoleptic properties of pan bread revealed that no significant differences (P≥0.05) between control sample and bread samples contained QF for taste and summitry form. The bread contained QF had higher score for crust color, pore size and overall acceptability than control sample. Hardness (g) of pan bread increased and springiness decreased gradually during storage of bread at (25˚c ±2). The rate of staling of bread contained QF lower than control sample. Gluten – free biscuit made from 100%QF contained the highest percentage of protein, lipids, ash and crude fiber compared to that of corn and rice – quinoa composite flour. The addition of corn and rice flour adversely affected on the thickness, diameter and spread ratio. The highest spread ratio was noticed in the biscuit made from 100% QF. It is worth mentioning that the biscuit made from 100 % QF or that of corn and rice – quinoa composite flour gave the biscuit with sensory acceptable. On the other hand, it could be noticed to that the biscuit contained high level of quinoa flour was darker in compared to another samples
A Guidebook: navigating custody and access negotiation
guidelines for family negotiation: what to do in the interest of minors after a family breakup
EFFECT OF BARLEY FLOUR ON WHEAT BREAD QUALITY
This study was carried out to investigate the possibility of utilization of barley flour in production of pan bread. wheat flour of (72% extract) was replaced by 10, 15 and 20% barley flour. The effect of such replacements on physical and chemical characteristics of produced pan bread were studied. The results indicated that barley flour had a higher contents of chemical composition than that in wheat flour except carbohydrate content was the highest in wheat flour (85.53%) than in barley flour (76.67%),whereas, protein, ash, dietary fiber, β-glucan and antioxidant were higher content in barley flour (13.63, 2.44, 19.00, 8.65, 97.34 respectively) as compared with its content in wheat flour (12.26, 0.49, 4.88, 0.34, 55.33 respctively),while, wet gluten and falling number were reduced by added barley in composite flour. The rheological properties of the five dough mixes were studied using farinograph and extensograph. The water absorption and dough weakening increased as the percentage of barley flour increased, while were decreased the extensibility and maximum resistance to extension . The results of sensory characteristies of prepared bread (containes10% barley flour) was not significants different from control for crust color, grain and texture. The results revealed that it was possible to use barley flour at level of 10, 15% to produce bread that satisfied baker's and consumer's sensory expectation. This levels may be to increased the nutritional value from dietary fibers, β-glucan, minerals, vitamins and antioxidants
Extraction of certain heavy metals from sewage sludge using different types of acids
The removal of heavy metal from sludge before disposal or application
to farmland is a necessary step to achieve a more safe sludge usage or
disposal. Chemical extraction using inorganic acids (nitric,
hydrochloric) and organic acids (citric, oxalic) were tested for
extraction of chromium, copper, nickel, lead and zinc from contaminated
sewage sludge at different pH and reaction time. Results revealed that
solubilization of metals using inorganic acids achieved its maximum
extraction efficiency (Cr-88%, Cu-82%, Ni-86%, Pb-94%, Zn-89%) at pH
value lower than 2 and acid contact times of 1hour. while in case of
organic acids oxalic acid does not show good results comparing to
citric acid that at pH 2.43 citric acid seemed to be highly effective
in extracting Cu (86%), Zn(88%), mostly after 1 day of extraction time,
Cr (90%), Ni (96%) at 5 days leaching time, while Pb(85%) removal at
the same pH was at a longer leaching time 10 days. At pH 3, citric acid
seemed to be also highly effective in extracting Cr (66%), Cu(48%), Pb
(66%), Zn(69%) at 1 day, while higher removal was also attained for
Ni(68%) at only 4 h leaching time. Finally the extraction efficiencies
of citric acid for Cr, Cu, Ni, Pb, Zn, are high enough to reduce the
heavy metal content in sludge to levels below the legal standards
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