Journal articles on the topic 'Lipid content of extracellular polymer'
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Janecka, J., M. B. Jenkins, N. S. Brackett, L. W. Lion, and W. C. Ghiorse. "Characterization of a Sinorhizobium Isolate and Its Extracellular Polymer Implicated in Pollutant Transport in Soil." Applied and Environmental Microbiology 68, no. 1 (January 2002): 423–26. http://dx.doi.org/10.1128/aem.68.1.423-426.2002.
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ABSTRACT A bacterium isolated from soil (designated 9702-M4) synthesizes an extracellular polymer that facilitates the transport of such hydrophobic pollutants as polynuclear aromatic hydrocarbons, as well as the toxic metals lead and cadmium in soil. Biolog analysis, growth rate determinations, and percent G+C content identify 9702-M4 as a strain of Sinorhizobium meliloti. Sequence analysis of a 16S rDNA fragment gives 9702-M4 a phylogenetic designation most closely related to Sinorhizobium fredii. The extracellular polymer of isolate 9702-M4 is composed of both an extracellular polysaccharide (EPS) and a rough lipopolysaccharide. The EPS component is composed mainly of 4-glucose linkages with monomers of galactose, mannose, and glucuronic acid and has pyruval and acetyl constituents. The lipid fraction and the negative charge associated with carbonyl groups of the exopolymer are thought to account for the binding of polynuclear aromatic hydrocarbons and cationic metals.
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Claus, Claudia, Robert Fritz, Erik Schilling, and Uta Reibetanz. "The Metabolic Response of Various Cell Lines to Microtubule-Driven Uptake of Lipid- and Polymer-Coated Layer-by-Layer Microcarriers." Pharmaceutics 13, no. 9 (September 10, 2021): 1441. http://dx.doi.org/10.3390/pharmaceutics13091441.
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Lipid structures, such as liposomes or micelles, are of high interest as an approach to support the transport and delivery of active agents as a drug delivery system. However, there are many open questions regarding their uptake and impact on cellular metabolism. In this study, lipid structures were assembled as a supported lipid bilayer on top of biopolymer-coated microcarriers based on the Layer-by-Layer assembly strategy. The functionalized microcarriers were then applied to various human and animal cell lines in addition to primary human macrophages (MΦ). Here, their influence on cellular metabolism and their intracellular localization were detected by extracellular flux analysis and immunofluorescence analysis, respectively. The impact of microcarriers on metabolic parameters was in most cell types rather low. However, lipid bilayer-supported microcarriers induced a decrease in oxygen consumption rate (OCR, indicative for mitochondrial respiration) and extracellular acidification rate (ECAR, indicative for glycolysis) in Vero cells. Additionally, in Vero cells lipid bilayer microcarriers showed a more pronounced association with microtubule filaments than polymer-coated microcarrier. Furthermore, they localized to a perinuclear region and induced nuclei with some deformations at a higher rate than unfunctionalized carriers. This association was reduced through the application of the microtubule polymerization inhibitor nocodazole. Thus, the effect of respective lipid structures as a drug delivery system on cells has to be considered in the context of the respective target cell, but in general can be regarded as rather low.
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Dregulo, A. M. "A STUDY OF HEAVY METAL COMPOSITIONS AND PHOSPHATES IN POLYMER SUBSTANCES OF THE ACTIVATED SLUDGE BIOMASS." Water and Ecology 25, no. 3 (2020): 8–13. http://dx.doi.org/10.23968/2305-3488.2020.25.3.8-13.
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Introduction. Heavy metals discharged with wastewater can lead to a toxic effect on the microbiocenosis of activated sludge and significantly decrease the degree of wastewater treatment, which dictates the need for a more detailed study and search for ways to detoxify activated sludge at the recycling stage and, at the same time, solve the problems of the neutralization of sewage sludge for safe soil disposal. To ensure the adequacy of the approach to the choice of the methodology for the neutralization of sludge, including sewage sludge, it is necessary to perform compositional analysis of their organic fractions and heavy metal compositions. Methods. To determine the quantitative content of organic components in activated sludge, a sample of sludge was dried to an air-dry state and then subjected to separation into fractions using a method based on the different solubility of compounds with the use of different solvents. Then, extractants were added step by step to the weighted samples of sewage sludge weighing about 2 g each (in a volume 20 times greater than the weight of the weighted sample (40 ml)). Results. The results of the study show that polysaccharides are the dominant form of the organic fraction (polymers) in sewage sludge. Most heavy metals were identified in acidic polysaccharides, humic-like acids and lipids. Significant concentrations of phosphates were observed for the same components of polymer substances in the biomass of activated sludges. Conclusion. The products of extraction of polymer substances of the activated sludge biomass and the content of heavy metals in them may indicate the biosorption of heavy metals by zoogleal accumulations (having a polysaccharide structure) of activated sludges in aeration tanks during biological treatment. Therefore, extracellular biopolymers can be a “target” in the development of targeted technologies for the neutralization of activated sludges.
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Gavalás-Olea, Antonio, Antje Siol, Yvonne Sakka, Jan Köser, Nina Nentwig, Thomas Hauser, Juliane Filser, Jorg Thöming, and Imke Lang. "Potential of the Red Alga Dixoniella grisea for the Production of Additives for Lubricants." Plants 10, no. 9 (September 4, 2021): 1836. http://dx.doi.org/10.3390/plants10091836.
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There is an increasing interest in algae-based raw materials for medical, cosmetic or nutraceutical applications. Additionally, the high diversity of physicochemical properties of the different algal metabolites proposes these substances from microalgae as possible additives in the chemical industry. Among the wide range of natural products from red microalgae, research has mainly focused on extracellular polymers for additive use, while this study also considers the cellular components. The aim of the present study is to analytically characterize the extra- and intracellular molecular composition from the red microalga Dixoniella grisea and to evaluate its potential for being used in the tribological industry. D. grisea samples, fractionated into extracellular polymers (EPS), cells and medium, were examined for their molecular composition. This alga produces a highly viscous polymer, mainly composed of polysaccharides and proteins, being secreted into the culture medium. The EPS and biomass significantly differed in their molecular composition, indicating that they might be used for different bio-additive products. We also show that polysaccharides and proteins were the major chemical compounds in EPS, whereas the content of lipids depended on the separation protocol and the resulting product. Still, they did not represent a major group and were thus classified as a potential valuable side-product. Lyophilized algal fractions obtained from D. grisea were found to be not toxic when EPS were not included. Upon implementation of EPS as a commercial product, further assessment on the environmental toxicity to enchytraeids and other soil organisms is required. Our results provide a possible direction for developing a process to gain an environmentally friendly bio-additive for application in the tribological industry based on a biorefinery approach.
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Kistriyani, Lilis, Zainus Salimin, and Achmad Chafidz. "Utilization of extracellular polymeric substances (EPS) immobilized in epoxy polymer as double ion exchanger biosorbent for removal of chromium from aqueous solution." Communications in Science and Technology 5, no. 1 (July 2, 2020): 40–44. http://dx.doi.org/10.21924/cst.5.1.2020.179.
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Cation and industrial pollutant anions are removed from wastewater using organic cation and anion exchange resin. "Extracellular Polymeric Substance" (EPS) from bacterial extraction can accumulate cation and anion elements through biosorption by adsorption mechanism, ion exchange, formation of complex compounds and hydrogen bonds. EPS can be used as an biosorbent and ion exchange bioresin replacing organic resins, because EPS contains organic functional groups that are negatively charged (RCOOH, ROPO3H, ROPO3Na, ROSO3H, ROSO3Na, etc.) cation absorbers and positively charged (ROH, RCNH2HCOOH, etc.) anion absorber. EPS consists of 40-95% polysaccharide compounds, protein 1-60%, nucleic acids 1-10%, lipids 1-10% and the remaining amino acid polymers and other compounds. The tannery industry produces trivalent (Cr+3) chromium pollutants at levels of 15.2 ppm and hexavalent (CrO4-2 or Cr2O7-2) levels of 0.77 ppm which exceeds the standard quality for a total Cr of 0.6 ppm. Cr pollutants are very dangerous for human health. Research had been done on the use of immobilized EPS bioresin in epoxy polymers for chromium binding. EPS was extracted from bacterial activated sludge by centrifugation at 9000 rpm for 20 minutes at 4°C, the filtrate was EPS. The analysis showed EPS content were 16% fat, 12% carbohydrate, and 16% protein. The functional group analysis results with infrared ray spectroscopy (FTIR) showed EPS containing chemical bonds such as -CH, -OH, -NH, and -C=O which proved that EPS extraction contained RCOOH, ROH, and RCNH2HCOOH functional components which were exchanging components cations and anions. Epoxy polymers were prepared by mixing bisphenol A monomers and 1: 1 ratio epichlorohydrin. Immobilized EPS double ion exchange biorecin in epoxy polymers was prepared by mixing 200 mg EPS and 1800 mg epoxy. The binding of chromium ions in the resin was carried out by recirculating the chromium solution through a burette column filled with 2 rams of bioresin at pH 5, 6 and 7. The optimum results gave chromium ion absorption efficiency of 89.20% at pH 5. Column operations could be optimized by varied the amount of bioresin used.
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Miot, Jennyfer, Karim Benzerara, Martin Obst, Andreas Kappler, Florian Hegler, Sebastian Sch�dler, Camille Bouchez, Fran�ois Guyot, and Guillaume Morin. "Extracellular Iron Biomineralization by Photoautotrophic Iron-Oxidizing Bacteria." Applied and Environmental Microbiology 75, no. 17 (July 10, 2009): 5586–91. http://dx.doi.org/10.1128/aem.00490-09.
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ABSTRACT Iron oxidation at neutral pH by the phototrophic anaerobic iron-oxidizing bacterium Rhodobacter sp. strain SW2 leads to the formation of iron-rich minerals. These minerals consist mainly of nano-goethite (α-FeOOH), which precipitates exclusively outside cells, mostly on polymer fibers emerging from the cells. Scanning transmission X-ray microscopy analyses performed at the C K-edge suggest that these fibers are composed of a mixture of lipids and polysaccharides or of lipopolysaccharides. The iron and the organic carbon contents of these fibers are linearly correlated at the 25-nm scale, which in addition to their texture suggests that these fibers act as a template for mineral precipitation, followed by limited crystal growth. Moreover, we evidence a gradient of the iron oxidation state along the mineralized fibers at the submicrometer scale. Fe minerals on these fibers contain a higher proportion of Fe(III) at cell contact, and the proportion of Fe(II) increases at a distance from the cells. All together, these results demonstrate the primordial role of organic polymers in iron biomineralization and provide first evidence for the existence of a redox gradient around these nonencrusting, Fe-oxidizing bacteria.
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Karaz, Selcan, Mertcan Han, Gizem Akay, Asim Onal, Sedat Nizamoglu, Seda Kizilel, and Erkan Senses. "Multiscale Dynamics of Lipid Vesicles in Polymeric Microenvironment." Membranes 12, no. 7 (June 21, 2022): 640. http://dx.doi.org/10.3390/membranes12070640.
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Understanding dynamic and complex interaction of biological membranes with extracellular matrices plays a crucial role in controlling a variety of cell behavior and functions, from cell adhesion and growth to signaling and differentiation. Tremendous interest in tissue engineering has made it possible to design polymeric scaffolds mimicking the topology and mechanical properties of the native extracellular microenvironment; however, a fundamental question remains unanswered: that is, how the viscoelastic extracellular environment modifies the hierarchical dynamics of lipid membranes. In this work, we used aqueous solutions of poly(ethylene glycol) (PEG) with different molecular weights to mimic the viscous medium of cells and nearly monodisperse unilamellar DMPC/DMPG liposomes as a membrane model. Using small-angle X-ray scattering (SAXS), dynamic light scattering, temperature-modulated differential scanning calorimetry, bulk rheology, and fluorescence lifetime spectroscopy, we investigated the structural phase map and multiscale dynamics of the liposome–polymer mixtures. The results suggest an unprecedented dynamic coupling between polymer chains and phospholipid bilayers at different length/time scales. The microviscosity of the lipid bilayers is directly influenced by the relaxation of the whole chain, resulting in accelerated dynamics of lipids within the bilayers in the case of short chains compared to the polymer-free liposome case. At the macroscopic level, the gel-to-fluid transition of the bilayers results in a remarkable thermal-stiffening behavior of polymer–liposome solutions that can be modified by the concentration of the liposomes and the polymer chain length.
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Li, Yiyong, Wanyi Luo, Wen Liu, Yongcong Yang, Zexiang Lei, Xueqin Tao, and Baoe Wang. "C058 and Other Functional Microorganisms Promote the Synthesis of Extracellular Polymer Substances in Mycelium Biofloc." Catalysts 12, no. 7 (June 24, 2022): 693. http://dx.doi.org/10.3390/catal12070693.
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The mycelium biofloc bioaugmented by Cordyceps strain C058 effectively purifies water, which may be related to the synthesis of extracellular polymer substances. To verify this conjecture, we analyzed the changes in extracellular polymer substances content in the mycelium biofloc under various hydraulic retention times (36 h, 18 h, and 11 h). The microstructure and microflora composition were analyzed using a scanning electron microscope and high-throughput sequencing. The ordinary biofloc without bioaugmentation was taken as a control. The results showed that under the above hydraulic retention time, the extracellular polymer substances contents of the mycelium biofloc were 51.20, 55.89, and 33.84 mg/g, respectively, higher than that of the ordinary biofloc (14.58, 15.72, and 18.19 mg/g). The protein content or the polysaccharide content also followed the same trend. Meanwhile, the sedimentation performance of the mycelium biofloc was better than that of the ordinary biofloc, attributed to the content of the extracellular polymer substances. It is worth noting that C058 is the main biofloc content, which promotes the synthesis of extracellular polymer substances in the mycelium biofloc. Other functional microorganisms in the mycelium biofloc were Janthinobacterium, Phormidium, Leptolyngbya, Hymenobacter, and Spirotrichea, which also promote the synthesis of extracellular polymer substances.
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Houghton, Jennifer I., and Tom Stephenson. "Effect of influent organic content on digested sludge extracellular polymer content and dewaterability." Water Research 36, no. 14 (August 2002): 3620–28. http://dx.doi.org/10.1016/s0043-1354(02)00055-6.
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Seneviratne, Rashmi, Rosa Catania, Michael Rappolt, Lars J. C. Jeuken, and Paul A. Beales. "Membrane mixing and dynamics in hybrid POPC/poly(1,2-butadiene-block-ethylene oxide) (PBd-b-PEO) lipid/block co-polymer giant vesicles." Soft Matter 18, no. 6 (2022): 1294–301. http://dx.doi.org/10.1039/d1sm01591e.
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Li, Lanlan, Ye Shi, Lijia Pan, Yi Shi, and Guihua Yu. "Rational design and applications of conducting polymer hydrogels as electrochemical biosensors." Journal of Materials Chemistry B 3, no. 15 (2015): 2920–30. http://dx.doi.org/10.1039/c5tb00090d.
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Li, Lanlan, Ye Shi, Lijia Pan, Yi Shi, and Guihua Yu. "Additional Article Notification: Rational design and applications of conducting polymer hydrogels as electrochemical biosensors." Journal of Materials Chemistry B 3, no. 25 (2015): 5111–21. http://dx.doi.org/10.1039/c5tb90093j.
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Chen, Suming, Amrita Datta-Chaudhuri, Pragney Deme, Alex Dickens, Raha Dastgheyb, Pavan Bhargava, Honghao Bi, and Norman J. Haughey. "Lipidomic characterization of extracellular vesicles in human serum." Journal of Circulating Biomarkers 8 (January 1, 2019): 184945441987984. http://dx.doi.org/10.1177/1849454419879848.
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There is a wide variety of extracellular vesicles (EVs) that differ in size and cargo composition. EVs isolated from human plasma or serum carry lipid, protein, and RNA cargo that provides insights to the regulation of normal physiological processes, and to pathological states. Specific populations of EVs have been proposed to contain protein and RNA cargo that are biomarkers for neurologic and systemic diseases. Although there is a considerable amount of evidence that circulating lipids are biomarkers for multiple disease states, it not clear if these lipid biomarkers are enriched in EVs, or if specific populations of EVs are enriched for particular classes of lipid. A highly reproducible workflow for the analysis of lipid content in EVs isolated from human plasma or serum would facilitate this area of research. Here we optimized an MS/MSALL workflow for the untargeted analysis of the lipid content in EVs isolated from human serum. A simple sequential ultracentrifugation protocol isolated three distinct types of serum EVs that were identified based on size, targeted protein, and untargeted lipidomic analyses. EVs in the upper and middle fractions were approximately 140 nm in diameter, while EVs in the pellet were approximately 110 nm in diameter. EVs in the upper most buoyant fractions contained the highest concentration of lipids, were enriched with phospholipids, and immunopositive for the cytoskeletal markers actin, α-actinin, and the mitochondrial protein mitofillin, but negative for the typical EV markers CD63, TSG101, and flotillin. A central fraction of EVs was devoid of cytoskeletal and mitochondrial markers, and positive for CD63, and TSG101, but negative for flotillin. The EV pellet contained no cytoskeletal or mitochondrial markers, but was positive for CD63, TSG101, and flotillin. The EV pellet contained the lowest concentration of most lipids, but was enriched with ceramide. These results provided new insights into the lipid composition of EVs isolated from serum using a simple ultracentrifugation isolation method suitable for lipidomic analysis by mass spectrometry.
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Galib, Mohammed A., Timothy Abbott, and Hyung-Sool Lee. "Examination of Extracellular Polymer (EPS) Extraction Methods for Anaerobic Membrane Bioreactor (AnMBR) Biomass." Sustainability 13, no. 22 (November 15, 2021): 12584. http://dx.doi.org/10.3390/su132212584.
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Membrane bioreactor fouling is a complex process, which is typically driven by extracellular polymeric substances (EPS), a complex mixture of polysaccharides, proteins, lipids, humic substances, and other intercellular polymers. While much is known about fouling in aerobic membrane reactors, far less is known about fouling in anaerobic membrane bioreactors (AnMBR). Much of this knowledge, including EPS extraction methods, has been extrapolated from aerobic processes and is commonly assumed to be comparable. Therefore, several extraction methods commonly used for aerobic EPS quantification, including ultrasonication, ethylenediaminetetraacetic acid (EDTA), and formaldehyde plus sodium hydroxide (CH2O+NaOH), were evaluated to determine the most suitable extraction method for EPS of anaerobic microorganisms in an AnMBR. To maximize EPS yields, each extraction was performed four times. Experimental results showed that the EDTA method was best for EPS quantification, based on chemical oxygen demand (COD), dissolved organic carbon (DOC), and protein yields: 1.43 mg COD/mg volatile suspended solids (VSS), 0.14 mg DOC/mg VSS, and 0.11 mg proteins/mg VSS. In comparison, the CH2O+NaOH method maximized the extraction of carbohydrates (0.12 mg carbohydrates/mg VSS). However, multiple extraction cycles with EDTA and ultrasonication exhibited lower extracellular adenosine triphosphate (ATP) concentrations compared to CH2O+NaOH extractions, indicating lower levels of released intracellular substances. Successive EPS extractions over four cycles are better able to quantify EPS from anaerobic microorganisms, since a single extraction may not accurately reflect the true levels of EPS contents in AnMBRs, and possibly in other anaerobic processes.
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Bowen, P. T., and T. M. Keinath. "Sludge Conditioning: Effects of Sludge Biochemical Composition." Water Science and Technology 17, no. 4-5 (April 1, 1985): 505–15. http://dx.doi.org/10.2166/wst.1985.0155.
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Variations in response of three different sludges to conditioning with organic polyelectrolytes were evaluated with respect to the carbohydrate, protein and lipid content of the sludges. These biochemicals comprise the surfaces of most sludges. The difference in the concentration of these compounds is intrinsic to the sludge type. Polymer Index (PI) , a measure of minimum polymer dose required to achieve maximum dewaterability, was statistically related to each of the three components. Carbohydrate content correlated most strongly with PI. As carbohydrate content increases, PI was found to decrease indicating better polymer performance. Biopolymers, which are composed mainly of carbohydrates may surround the cells forming a highly reactive surface. These exocellular materials also promote bioflocculation. Both actions result in a lower polymer requirement for destabilizing the sludge. Protein and lipid were not observed to have strong correlation with PI. Cellular surfaces and structures are composed of these components. The low correlation indicates these components are less favored than carbohydrates for polymer interaction.
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Berria, Rachele, Lishan Wang, Dawn K. Richardson, Jean Finlayson, Renata Belfort, Thongchai Pratipanawatr, Elena A. De Filippis, Sangeeta Kashyap, and Lawrence J. Mandarino. "Increased collagen content in insulin-resistant skeletal muscle." American Journal of Physiology-Endocrinology and Metabolism 290, no. 3 (March 2006): E560—E565. http://dx.doi.org/10.1152/ajpendo.00202.2005.
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Oversupply and underutilization of lipid fuels are widely recognized to be strongly associated with insulin resistance in skeletal muscle. Recent attention has focused on the mechanisms underlying this effect, and defects in mitochondrial function have emerged as a potential player in this scheme. Because evidence indicates that lipid oversupply can produce abnormalities in extracellular matrix composition and matrix changes can affect the function of mitochondria, the present study was undertaken to determine whether muscle from insulin-resistant, nondiabetic obese subjects and patients with type 2 diabetes mellitus had increased collagen content. Compared with lean control subjects, obese and type 2 diabetic subjects had reduced muscle glucose uptake ( P < 0.01) and decreased insulin stimulation of tyrosine phosphorylation of insulin receptor substrate-1 and its ability to associate with phosphatidylinositol 3-kinase ( P < 0.01 and P < 0.05). Because it was assayed by total hydroxyproline content, collagen abundance was increased in muscle from not only type 2 diabetic patients but also nondiabetic obese subjects (0.26 ± 0.05, 0.57 ± 0.18, and 0.67 ± 0.20 μg/mg muscle wet wt, lean controls, obese nondiabetics, and type 2 diabetics, respectively), indicating that hyperglycemia itself could not be responsible for this effect. Immunofluorescence staining of muscle biopsies indicated that there was increased abundance of types I and III collagen. We conclude that changes in the composition of the extracellular matrix are a general characteristic of insulin-resistant muscle.
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Jia, X. S., Herbert H. P. Fang, and H. Furumai. "Surface charge and extracellular polymer of sludge in the anaerobic degradation process." Water Science and Technology 34, no. 5-6 (September 1, 1996): 309–16. http://dx.doi.org/10.2166/wst.1996.0565.
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Changes of surface charge and extracellular polymer (ECP) content were investigated in batch experiments for three anaerobic sludges, each of which had been enriched at 35°C and pH 639-7.3 for more than 40 batches using propionate, butyrate and glucose, individually, as the sole substrate. Results showed that both ECP and the negative surface charge were dependent on the growth phase of microorganisms. They increased at the beginning of all batches when the microorganisms were in the prolific-growth phase, having high substrate concentration and food-to-microorganisms ratio. Both later gradually returned to their initial levels when the microorganisms were in the declined-growth phase, as the substrate became depleted. The negative surface charge increased linearly with the total-ECP content in all series with slopes of 0.0187, 0.0212 and 0.0157 meq/mg-total-ECP for sludge degrading propionate, butyrate and glucose, respectively. The change of surface charge for the first two sludges was mainly due to the increase of proteinaceous fraction of ECP; but, for glucose-degrading sludge, that could be due to the increases of both proteinaceous and carbohydrate fractions of ECP. The negative-charged nature of anaerobic sludge implies that cations should be able to promote granulation of anaerobic sludge.
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Boilard, Eric. "Extracellular vesicles and their content in bioactive lipid mediators: more than a sack of microRNA." Journal of Lipid Research 59, no. 11 (April 20, 2018): 2037–46. http://dx.doi.org/10.1194/jlr.r084640.
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Sun, Saito, and Saito. "Lipid Profile Characterization and Lipoprotein Comparison of Extracellular Vesicles from Human Plasma and Serum." Metabolites 9, no. 11 (November 1, 2019): 259. http://dx.doi.org/10.3390/metabo9110259.
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Extracellular vesicles (EVs) consist of lipid bilayers, occur in various biofluids, and are invaluable in biomarker screening. Liquid chromatography coupled with high-resolution mass spectrometry (LC-MS) was recently used to study comprehensive EV lipid profiles in vitro. The aim of this study was to establish a lipidomics platform for human plasma and serum EVs for comprehensive characterization of their lipid profiles, and to compare them with those of other lipid-containing particles, such as high-density lipoproteins (HDL), and low/very low-density lipoproteins (LDL/VLDL). Isolation was validated by specific protein markers; CD9 and MHC class for EVs, apoA-I for HDL, and apoB-100 for LDL/VLDL. Lipidomics identified 264 lipids from isolated plasma EVs, HDL, and LDL/VLDL. The absolute lipid levels per unit protein content in the EVs were more than eight times lower than those of the lipoproteins. Moreover, the EVs had higher lysoglycerophospholipid levels than HDL or LDL/VLDL. Similar profiles were also determined for human serum. The present study found that the lipid profiles of EVs are unique and distinctly different from those of lipoproteins. The lipidomics platform applied to human plasma and serum EVs could generate important information for the exploration and qualification of biomarkers in disease diagnosis.
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Durmaz, B., and F. D. Sanin. "Effect of carbon to nitrogen ratio on the composition of microbial extracellular polymers in activated sludge." Water Science and Technology 44, no. 10 (November 1, 2001): 221–29. http://dx.doi.org/10.2166/wst.2001.0626.
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Effect of carbon to nitrogen ratio (C/N) on the sludge extracellular polymer composition is studied in synthetically fed semi-continuous reactors with 8 days of sludge age. Results show that C/N ratio influences the relative distribution of polymer carbohydrate and protein. At low C/N ratio of 5, polymer extracts have high protein and low carbohydrate content. As the C/N ratio is increased to 17.5 and then to 40, carbohydrate concentration increases sharply and protein concentration decreases.
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Buchet, R., and S. Pikuła. "Alzheimer's disease: its origin at the membrane, evidence and questions." Acta Biochimica Polonica 47, no. 3 (September 30, 2000): 725–33. http://dx.doi.org/10.18388/abp.2000_3991.
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Numerous results on membrane lipid composition from different regions of autopsied Alzheimer's disease brains in comparison with corresponding fractions isolated from control brains revealed significant differences in serine- and ethanolamine-containing glycerophospholipid as well as in glycosphingolipid content. Changes in membrane lipid composition are frequently accompanied by alterations in membrane fluidity, hydrophobic mismatch, lipid signaling pathways, transient formation and disappearance of lipid microdomains, changes in membrane permeability to cations and variations of other membrane properties. In this review we focus on possible implications of altered membrane composition on beta-amyloid precursor protein (APP) and on proteolysis of APP leading eventually to the formation of neurotoxic beta-amyloid (A beta) peptides, the major proteinaceous component of extracellular senile plaques, directly involved in Alzheimer's disease pathogenesis.
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Williams, Charles, Mari Palviainen, Niels-Christian Reichardt, Pia R. M. Siljander, and Juan M. Falcón-Pérez. "Metabolomics Applied to the Study of Extracellular Vesicles." Metabolites 9, no. 11 (November 12, 2019): 276. http://dx.doi.org/10.3390/metabo9110276.
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Cell-secreted extracellular vesicles (EVs) have rapidly gained prominence as sources of biomarkers for non-invasive biopsies, owing to their ubiquity across human biofluids and physiological stability. There are many characterisation studies directed towards their protein, nucleic acid, lipid and glycan content, but more recently the metabolomic analysis of EV content has also gained traction. Several EV metabolite biomarker candidates have been identified across a range of diseases, including liver disease and cancers of the prostate and pancreas. Beyond clinical applications, metabolomics has also elucidated possible mechanisms of action underlying EV function, such as the arginase-mediated relaxation of pulmonary arteries or the delivery of nutrients to tumours by vesicles. However, whilst the value of EV metabolomics is clear, there are challenges inherent to working with these entities—particularly in relation to sample production and preparation. The biomolecular composition of EVs is known to change drastically depending on the isolation method used, and recent evidence has demonstrated that changes in cell culture systems impact upon the metabolome of the resulting EVs. This review aims to collect recent advances in the EV metabolomics field whilst also introducing researchers interested in this area to practical pitfalls in applying metabolomics to EV studies.
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Nasci, Victoria L., Sandra Chuppa, Lindsey Griswold, Kathryn A. Goodreau, Ranjan K. Dash, and Alison J. Kriegel. "miR-21-5p regulates mitochondrial respiration and lipid content in H9C2 cells." American Journal of Physiology-Heart and Circulatory Physiology 316, no. 3 (March 1, 2019): H710—H721. http://dx.doi.org/10.1152/ajpheart.00538.2017.
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Cardiovascular-related pathologies are the single leading cause of death in patients with chronic kidney disease (CKD). Previously, we found that a 5/6th nephrectomy model of CKD leads to an upregulation of miR-21-5p in the left ventricle, targeting peroxisome proliferator-activated receptor-α and altering the expression of numerous transcripts involved with fatty acid oxidation and glycolysis. In the present study, we evaluated the potential for knockdown or overexpression of miR-21-5p to regulate lipid content, lipid peroxidation, and mitochondrial respiration in H9C2 cells. Cells were transfected with anti-miR-21-5p (40 nM), pre-miR-21-5p (20 nM), or the appropriate scrambled oligonucleotide controls before lipid treatment in culture or as part of the Agilent Seahorse XF fatty acid oxidation assay. Overexpression of miR-21-5p attenuated the lipid-induced increase in cellular lipid content, whereas suppression of miR-21-5p augmented it. The abundance of malondialdehyde, a product of lipid peroxidation, was significantly increased with lipid treatment in control cells but attenuated in pre-miR-21-5p-transfected cells. This suggests that miR-21-5p reduces oxidative stress. The cellular oxygen consumption rate (OCR) was increased in both pre-miR-21-5p- and anti-miR-21-5p-transfected cells. Levels of intracellular ATP were significantly higher in anti-mR-21-5p-transfected cells. Pre-miR-21-5p blocked additional increases in OCR in response to etomoxir and palmitic acid. Conversely, anti-miR-21-5p-transfected cells exhibited reduced OCR with both etomoxir and palmitic acid, and the glycolytic capacity was concomitantly reduced. Together, these results indicate that overexpression of miR-21-5p attenuates both lipid content and lipid peroxidation in H9C2 cells. This likely occurs by reducing cellular lipid uptake and utilization, shifting cellular metabolism toward reliance on the glycolytic pathway. NEW & NOTEWORTHY Both overexpression and suppression of miR-21-5p augment basal and maximal mitochondrial respiration. Our data suggest that reliance on glycolytic and fatty acid oxidation pathways can be modulated by the abundance of miR-21-5p within the cell. miR-21-5p regulation of mitochondrial respiration can be modulated by extracellular lipids.
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Ram, S. K., L. R. Kumar, R. D. Tyagi, and P. Drogui. "Techno-economic evaluation of simultaneous production of extra-cellular polymeric substance (EPS) and lipids by Cloacibacterium normanense NK6 using crude glycerol and sludge as substrate." Water Science and Technology 77, no. 9 (March 27, 2018): 2228–41. http://dx.doi.org/10.2166/wst.2018.140.
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Abstract This study used the technical, economic analysis tool, SuperPro designer in evaluating a novel technology for simultaneous production of extracellular polymeric substance (EPS) and biodiesel using crude glycerol and secondary sludge. As renewable energy sources are depleting, the process utilizes municipal sewage sludge for production of EPS and biodiesel along with crude glycerol, which is a waste byproduct of biodiesel industry providing an alternate way for disposal of municipal sludge and crude glycerol. Newly isolated Cloacibacterium normanense NK6 is used as micro-organism in the study as it is capable of producing high EPS concentration, using activated sludge and crude glycerol as the sole carbon source. The technology has many environmental and economic advantages like the simultaneous production of two major products: EPS and lipids. Sensitivity analysis of the process revealed that biomass lipid content is a most significant factor where unit cost production of biodiesel was highly sensitive to lipid content during bioreaction. B7 biodiesel unit production cost can be lowered from $1 to $0.6 if the lipid content of the biomass is improved by various process parameter modifications.
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Davies, M. J., P. D. Richardson, N. Woolf, D. R. Katz, and J. Mann. "Risk of thrombosis in human atherosclerotic plaques: role of extracellular lipid, macrophage, and smooth muscle cell content." Heart 69, no. 5 (May 1, 1993): 377–81. http://dx.doi.org/10.1136/hrt.69.5.377.
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Rupert, Déborah L. M., Mokhtar Mapar, Ganesh Vilas Shelke, Karin Norling, Mathias Elmeskog, Jan O. Lötvall, Stephan Block, Marta Bally, Björn Agnarsson, and Fredrik Höök. "Effective Refractive Index and Lipid Content of Extracellular Vesicles Revealed Using Optical Waveguide Scattering and Fluorescence Microscopy." Langmuir 34, no. 29 (June 20, 2018): 8522–31. http://dx.doi.org/10.1021/acs.langmuir.7b04214.
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Ceccarelli, Lorenzo, Chiara Giacomelli, Laura Marchetti, and Claudia Martini. "Microglia extracellular vesicles: focus on molecular composition and biological function." Biochemical Society Transactions 49, no. 4 (August 20, 2021): 1779–90. http://dx.doi.org/10.1042/bst20210202.
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Extracellular vesicles (EVs) are a heterogeneous family of cell-derived lipid bounded vesicles comprising exosomes and microvesicles. They are potentially produced by all types of cells and are used as a cell-to-cell communication method that allows protein, lipid, and genetic material exchange. Microglia cells produce a large number of EVs both in resting and activated conditions, in the latter case changing their production and related biological effects. Several actions of microglia in the central nervous system are ascribed to EVs, but the molecular mechanisms by which each effect occurs are still largely unknown. Conflicting functions have been ascribed to microglia-derived EVs starting from the neuronal support and ending with the propagation of inflammation and neurodegeneration, confirming the crucial role of these organelles in tuning brain homeostasis. Despite the increasing number of studies reported on microglia-EVs, there is also a lot of fragmentation in the knowledge on the mechanism at the basis of their production and modification of their cargo. In this review, a collection of literature data about the surface and cargo proteins and lipids as well as the miRNA content of EVs produced by microglial cells has been reported. A special highlight was given to the works in which the EV molecular composition is linked to a precise biological function.
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Han, Xiangpeng, Qingying Chen, Xingguo Zhang, Xiaolan Chen, Dongsheng Luo, and Qingping Zhong. "Antibiofilm and Antiquorum Sensing Potential of Lactiplantibacillus plantarum Z057 against Vibrio parahaemolyticus." Foods 11, no. 15 (July 27, 2022): 2230. http://dx.doi.org/10.3390/foods11152230.
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Vibrio parahaemolyticus is a widespread foodborne pathogen that causes serious seafood-borne gastrointestinal infections. Biofilm and quorum sensing (QS) are critical in regulating these infections. In this study, first, the ability of Lactiplantibacillus plantarum Z057 to compete, exclude, and displace V. parahaemolyticus biofilm was evaluated. Then, the inhibitory effects of L. plantarum Z057 extract (Z057-E) on V. parahaemolyticus biofilm and QS were explored from the aspects of biofilm biomass, metabolic activity, physicochemical properties, extracellular polymer matrix content, QS signal AI-2 activity, biofilm microstructure, and the expression levels of biofilm and QS-related genes. Results showed that L. plantarum Z057 effectively inhibited biofilm formation of V. parahaemolyticus and interfered with the adhesion of V. parahaemolyticus on the carrier surface. In addition, the Z057-E could significantly reduce the biofilm biomass, metabolic activity, hydrophobicity, auto-aggregation ability, swimming and swarming migration diameter, AI-2 activity, extracellular polysaccharide (EPS), and extracellular protein content of V. parahaemolyticus. Fluorescence microscope and scanning electron microscope (SEM) images demonstrated that the Z057-E could efficiently inactivate the living cells, destroy the dense and complete biofilm architectures, and reduce the essential component of the extracellular polymer matrix. Real-time fluorescence quantitative PCR revealed that the Z057-E treatment down-regulated the expression of flagellum synthesis-related genes (flaA, flgM), EPS, and extracellular protein synthesis-related genes (cpsA, cpsQ, cpsR, ompW), QS-related genes (luxS, aphA, opaR), and hemolysin secretion-related genes (toxS, toxR) of V. parahaemolyticus. Thus, our results suggested that L. plantarum Z057 could represent an alternative biocontrol strategy against foodborne pathogens with anti-adhesive, antibiofilm, and antiquorum sensing activities.
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Samuels, Mark, Chiara Cilibrasi, Panagiotis Papanastasopoulos, and Georgios Giamas. "Extracellular Vesicles as Mediators of Therapy Resistance in the Breast Cancer Microenvironment." Biomolecules 12, no. 1 (January 14, 2022): 132. http://dx.doi.org/10.3390/biom12010132.
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Resistance to various therapies, including novel immunotherapies, poses a major challenge in the management of breast cancer and is the leading cause of treatment failure. Bidirectional communication between breast cancer cells and the tumour microenvironment is now known to be an important contributor to therapy resistance. Several studies have demonstrated that crosstalk with the tumour microenvironment through extracellular vesicles is an important mechanism employed by cancer cells that leads to drug resistance via changes in protein, lipid and nucleic acid cargoes. Moreover, the cargo content enables extracellular vesicles to be used as effective biomarkers for predicting response to treatments and as potential therapeutic targets. This review summarises the literature to date regarding the role of extracellular vesicles in promoting therapy resistance in breast cancer through communication with the tumour microenvironment.
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Jonca, Nathalie. "Ceramides metabolism and impaired epidermal barrier in cutaneous diseases and skin aging: focus on the role of the enzyme PNPLA1 in the synthesis of ω-O-acylceramides and its pathophysiological involvement in some forms of congenital ichthyoses." OCL 26 (2019): 17. http://dx.doi.org/10.1051/ocl/2019013.
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The outermost layer of the skin, the stratum corneum, is essential for the protective barrier functions of the skin. It results from the stacking of corneocytes, the dead flattened cells resulting from epidermal terminal differentiation of underlying living keratinocytes. The cornified lipid envelope, encapsulating corneocytes, and the extracellular mortar-like multilayered lipid matrix, called lamellae, are two crucial elements of the epidermal barrier. Stratum corneum extracellular lipids are mainly composed of ceramides, cholesterol and free fatty acids. Ceramides, and more specifically the epidermis specific ω-O-acylceramides, are essential for lipid-matrix organization into lamellae and formation of the corneocyte lipid envelope. Pathophysiological studies of inherited lipid metabolism disorders recently contributed to a better understanding of stratum corneum lipid metabolism. In the lab, our data from patients with Autosomal Recessive Congenital Ichthyosis and a murine knock-out model showed that the enzyme PNPLA1 is essential for the last step of synthesis of omega-O-acylceramides. Skin aging is a complex biological process caused by genetic and extrinsic factors e.g. sun exposure, smoke, and pollution. Aging skin is marked by a senescence-related decline in lipid and water content, which ultimately impairs epidermal barrier function. Thus, aged epidermis is prone to develop altered drug permeability, increased susceptibility to irritants contact dermatitis and severe xerosis. Ceramide deficiency may account, at least in part, for the dysfunction of the stratum corneum associated with ageing. Hence, treatments able to increase skin-ceramide levels could improve the epidermal barrier function in aged skin. Many animal testing and clinical trials are taken in that regard.
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Catandi, Giovana D., Yusra M. Obeidat, Corey D. Broeckling, Thomas W. Chen, Adam J. Chicco, and Elaine M. Carnevale. "Equine maternal aging affects oocyte lipid content, metabolic function and developmental potential." Reproduction 161, no. 4 (April 2021): 399–409. http://dx.doi.org/10.1530/rep-20-0494.
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Advanced maternal age is associated with a decline in fertility and oocyte quality. We used novel metabolic microsensors to assess effects of mare age on single oocyte and embryo metabolic function, which has not yet been similarly investigated in mammalian species. We hypothesized that equine maternal aging affects the metabolic function of oocytes and in vitro-produced early embryos, oocyte mitochondrial DNA (mtDNA) copy number, and relative abundance of metabolites involved in energy metabolism in oocytes and cumulus cells. Samples were collected from preovulatory follicles from young (≤14 years) and old (≥20 years) mares. Relative abundance of metabolites in metaphase II oocytes (MII) and their respective cumulus cells, detected by liquid and gas chromatography coupled to mass spectrometry, revealed that free fatty acids were less abundant in oocytes and more abundant in cumulus cells from old vs young mares. Quantification of aerobic and anaerobic metabolism, respectively measured as oxygen consumption rate (OCR) and extracellular acidification rate (ECAR) in a microchamber containing oxygen and pH microsensors, demonstrated reduced metabolic function and capacity in oocytes and day-2 embryos originating from oocytes of old when compared to young mares. In mature oocytes, mtDNA was quantified by real-time PCR and was not different between the age groups and not indicative of mitochondrial function. Significantly more sperm-injected oocytes from young than old mares resulted in blastocysts. Our results demonstrate a decline in oocyte and embryo metabolic activity that potentially contributes to the impaired developmental competence and fertility in aged females.
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Martin, Breonna J., and Kenneth L. van Golen. "A Comparison of Cholesterol Uptake and Storage in Inflammatory and Noninflammatory Breast Cancer Cells." International Journal of Breast Cancer 2012 (2012): 1–10. http://dx.doi.org/10.1155/2012/412581.
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Although there are many subtypes of breast cancer, inflammatory breast cancer (IBC) is arguably the deadliest. Research over the past decade has demonstrated that IBC is a distinct entity from other forms of breast cancer. Important risk factors that have been associated with the development of aggressive breast cancers, such as IBC, include obesity and diet, which are evident in the United States, where the overconsumption of high-fat foods continues to contribute to obesity in the nation. Here we investigate differences in cholesterol uptake and storage between IBC, non-IBC, and mammary epithelial cell lines. Our results demonstrate that compared with human mammary epithelial cells (HMECs), both IBC and non-IBC cells have increased cholesterol content. IBC cells retain intracellular cholesterol esters, free cholesterol, and triglycerides in lipid-deficient environments. In contrast, we observe in cell-type-of-origin-matched non-IBC a significant decrease in lipid content under the same lipid-deficient conditions. These data suggest that cholesterol storage may be affected by the cholesterol content of the environment where the tumor cell was isolated. Here, we suggest that breast cancer cells may migrate when they are unable to obtain cholesterol from their extracellular environments.
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Li, Yajing, Yaping Wu, Shaopo Wang, and Liyuan Jia. "Effect of organic loading on phosphorus forms transformation and microbial community in continuous-flow A2/O process." Water Science and Technology 83, no. 11 (April 26, 2021): 2640–51. http://dx.doi.org/10.2166/wst.2021.158.
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Abstract A continuous-flow Anaerobic/Anoxic/Oxic (A2/O) system was operated at different organic concentrations to systematically investigate the effect on the nutrient removal, secretion characteristics of extracellular polymer, phosphorus forms transformation and changes in functional flora in this system. The results showed that high organic loading was more conducive to promote the secretion of extracellular polymeric substance (EPS), the increase of polysaccharide content was more obvious compared with protein, the impact of organic loading on the components of loosely bound EPS (LB-EPS) was higher than that of tight-bound EPS (TB-EPS). Phosphorus in sludge floc mainly existed in the form of inorganic phosphorus (IP), and IP mainly existed in the form of apatite inorganic phosphorus (AP). High organic load showed higher phosphorus storage in EPS, and the phosphorus content in EPS was positively correlated with the content of EPS. Non-apatite phosphorus (NAIP) content played an important role in the extracellular dephosphorization. The abundance of Nitrosomonas and Nitrospira responsible for nitrification decreased with the increase in organic loading. The group of denitrifiers was large, and Azospira was the most abundant genus among them. Dechloromonas, Acinetobacter, Povalibacter, Chryseolinea and Pirellula were the functional genera closely associated with phosphorus removal.
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Yan, L. L., X. L. Zhang, Z. L. Chen, Y. Ren, S. Liu, M. Y. Zhang, Y. Liu, Q. P. Liu, and L. B. Yu. "Effects of Phosphorus on Loosely Bound and Tightly Bound Extracellular Polymer Substances in Aerobic Granular Sludge." Chemical & biochemical engineering quarterly 33, no. 1 (2019): 59–68. http://dx.doi.org/10.15255/cabeq.2018.1445.
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The stability of aerobic granular sludge (AGS) is closely related to its extracellular polymeric substances (EPS). In this study, the composition and physicochemical characteristics of EPS in AGS were determined to evaluate their roles in AGS stability. The study evaluated the influence of influent phosphorus concentration on EPS protein (PN), polysaccharide (PS) and orthophosphate content, zeta potential (ζ) and fluorescence spectrum (EEM) in loosely bound EPS (LB-EPS) and tightly bound EPS (TB-EPS). With higher influent phosphorus concentration, the PN, PS and orthophosphate content were higher, as was the zeta potential in TB-EPS, but it had less influence on LB-EPS. Three-dimensional, synchronous fluorescence spectroscopy and fluorescence region integral (FRI) showed that protein-like substances were the primary components of LB-EPS and TB-EPS. Phosphorus had a dynamic quenching effect on EPS at a concentration between 0 mg L–1 and 17.5 mg L–1, which is the indirect production of phosphorus by cations. An increased concentration of influent phosphorus was beneficial to AGS stability
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Cheng-Mao, Xie, Long Yan, Lin Li, Jin Hua, Wang Xiao-Ju, and Zhang Jie-Wen. "Placental ABCA1 Expression Is Increased in Spontaneous Preterm Deliveries Compared with Iatrogenic Preterm Deliveries and Term Deliveries." BioMed Research International 2017 (2017): 1–9. http://dx.doi.org/10.1155/2017/8248094.
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Objective. Abnormal expression of ABCA1 and ABCG1 in the placenta can elicit lipid metabolism disorder and adverse pregnancy outcomes. However, whether it is associated with preterm delivery remains unclear. Our present study aimed to evaluate the relationship between abnormal expression of ABCA1 or ABCG1 and preterm delivery. Methods. Maternal blood and placental tissues from women with spontaneous deliveries (SPD), iatrogenic deliveries (IPD), and term deliveries (TD) were collected. The lipid content and expression of ABCA1 and ABCG1 were subsequently measured. Results. Compared with IPD and TD groups, the HDL, TD, LDL, and TC levels were lower in the maternal blood but higher (except TC) in the cord blood of the SPD group. The extracellular lipid content in the placentas of the SPD group was also notably lower relative to the IPD and TD groups. Moreover, the protein and mRNA expressions of ABCA1 in the placentas of the SPD group were significantly higher compared with the IPD and TD groups; however, there was no obvious difference among the three groups in the protein and mRNA expressions of ABCG1. Conclusions. Abnormal expression of ABCA1 may be associated with the dysregulation of placental lipid metabolism and the occurrence or development of SPD.
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Cindrić, Marina, Ana Čipak Gašparović, Lidija Milković, Ivana Tartaro Bujak, Branka Mihaljević, Neven Žarković, and Kamelija Žarković. "4-Hydroxynonenal Modulates Blood–Brain Barrier Permeability In Vitro through Changes in Lipid Composition and Oxidative Status of Endothelial Cells and Astrocytes." International Journal of Molecular Sciences 23, no. 22 (November 19, 2022): 14373. http://dx.doi.org/10.3390/ijms232214373.
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Blood brain barrier (BBB) is a dynamic interface responsible for proper functioning of brain, but also a major obstacle for effective treatment of neurological diseases. Increased levels of free radicals, in high ferrous and high lipid content surrounding, induce lipid peroxidation, leading to production of 4-hydroxynonenal (HNE). HNE modifies all key proteins responsible for proper brain functioning thus playing a major role in the onset of neurological diseases. To investigate HNE effects on BBB permeability, we developed two in vitro BBB models–‘physiological’ and ‘pathological’. The latter mimicked HNE modified extracellular matrix under oxidative stress conditions in brain pathologies. We showed that exogenous HNE induce activation of antioxidative defense systems by increasing catalase activity and glutathione content as well as reducing lipid peroxide levels in endothelial cells and astrocytes of ‘physiological’ model. While in ‘pathological’ model, exogenous HNE further increased lipid peroxidation levels of endothelial cells and astrocytes, followed by increase in Nrf2 and glutathione levels in endothelial cells. At lipid composition level, HNE caused increase in ω3 polyunsaturated fatty acid (PUFA) level in endothelial cells, followed by decrease in ω3 PUFA level and increase in monounsaturated fatty acid level in astrocytes. Using these models, we showed for the first time that HNE in ‘pathological’ model can reduce BBB permeability.
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Bunkin, Nikolai F., Polina N. Bolotskova, Elena V. Bondarchuk, Valery G. Gryaznov, Valeriy A. Kozlov, Maria A. Okuneva, Oleg V. Ovchinnikov, Nikita V. Penkov, Oleg P. Smoliy, and Igor F. Turkanov. "Dynamics of Polymer Membrane Swelling in Aqueous Suspension of Amino-Acids with Different Isotopic Composition; Photoluminescence Spectroscopy Experiments." Polymers 13, no. 16 (August 7, 2021): 2635. http://dx.doi.org/10.3390/polym13162635.
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In photoluminescence spectroscopy experiments, the interaction mode of the polymer membrane Nafion with various amino-acids was studied. The experiments were performed with physiological NaCl solutions prepared in an ordinary water (the deuterium content is 157 ± 1 ppm) and also in deuterium-depleted water (the deuterium content is ≤1 ppm). These studies were motivated by the fact that when Nafion swells in ordinary water, the polymer fibers are effectively “unwound” into the liquid bulk, while in the case of deuterium-depleted water, the unwinding effect is missing. In addition, polymer fibers, unwound into the liquid bulk, are similar to the extracellular matrix (glycocalyx) on the cell membrane surface. It is of interest to clarify the role of unwound fibers in the interaction of amino-acids with the polymer membrane surface. It turned out that the interaction of amino-acids with the membrane surface gives rise to the effects of quenching luminescence from the luminescence centers. We first observed various dynamic regimes arising upon swelling the Nafion membrane in amino-acid suspension with various isotopic content, including triggering effects, which is similar to the processes in the logical gates of computers.
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Obuotor, T. M., A. J. Okewale, and A. M. Taiwo. "Biodegradation of Vegetable Oil Factory Effluent Using Extracellular Lipase Obtained from Alcaligenes Spp." Journal of Solid Waste Technology and Management 46, no. 3 (August 1, 2020): 223–29. http://dx.doi.org/10.5276/jswtm/2020.223.
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This study determined the degradation of vegetable oil factory effluent by extracellular lipase obtained from Alcaligenes spp. The extracellular lipase produced by isolated Alcaligenes spp was obtained and concentrated using Glycerol before Gel Filtration Chromatography. The partially purified enzyme obtained from the Gel Filtration Chromatography purification showed optimum activity at a temperature of 55° C and pH 7. The enzyme was then concentrated using glycerol prior to treatment. The raw effluent samples (from the vegetable oil factory) were treated with the partially purified enzyme for 20 days. The degradation activity of the enzymes on contaminant concentrations was monitored at every 5 days. A control experiment was also set up for possible natural degradation of contaminants. Effluents were analyzed for metals (Fe, Mn and Zn), Chemical Oxygen Demand (COD) and Lipid Content using the standard method. Data were analysed for graphical presentation using the Microsoft Excel package. Results showed reduction in Fe, Mn, Zn, COD and Lipid Contents between day 5 and 20 as 46.28%, 68.71%, 62.53%, 71.45% and 72.57% respectively. The application of extracellular enzyme in the treatment of the effluent enhanced the degradation of the effluent at a higher percentage than the natural attenuation process of the effluent. This showed the promising bioremediation potential of Alcaligenes spp.
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Gileva, O. G., E. G. Butolin, and M. V. Tereshchenko. "Serum level of laminin in rats fed with a high-fat diet with sulodexide administration." Bulletin of Siberian Medicine 21, no. 1 (April 12, 2022): 21–27. http://dx.doi.org/10.20538/1682-0363-2022-1-21-27.
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Background. Increased consumption of animal fat with food contributes to the accumulation of lipids both in the blood and in individual cell structures. Excess fat initiates oxidative stress reactions, which may result in a violation of the structural and functional integrity of cells, in particular, hepatocytes and endotheliocytes. Cytolysis may release specific liver enzymes and activate synthesis of extracellular matrix components, one of the markers of which is a non-collagen glycoprotein laminin.The drug sulodexide, having a pronounced angioprotective, hypolipidemic, and fibrinolytic effects, contributes to restoration of a number of metabolic disorders.Aim. To study the content of lipid metabolism parameters, major enzymes of hepatic cytolysis, and laminin in the blood of rats fed with a high-fat diet against the background of sulodexide administration.Materials and methods. For the study, outbred rats were selected, which were divided into three groups – two experimental groups and one control group. The rats of the first and second experimental groups were fed with a diet with a high content of animal fat (44% of the daily calorie content) for 35 days. In addition, the rats of the second experimental group were daily subcutaneously injected with sulodexide at a dose of 8.5 LRU / kg in terms of the animal’s body weight for 35 days. Starting from day 36 of the experiment, the rats of the control group, as well as the rats of the two experimental groups were fed with a standard diet of the vivarium. The animals were decapitated and blood was taken on day 21, 35, and 60 of the experiment. In the blood serum, the levels of the main lipid metabolism parameters, specific liver enzymes, and laminin were determined.Results. An increase in the body weight of animals and the level of the studied lipid metabolism parameters in the blood serum was revealed. It is likely that the structural integrity of hepatocytes was affected with the release of liver enzymes into the bloodstream and an increase in their content in the blood of rats. In addition, synthesis of extracellular matrix components was activated with an increase in the serum level of laminin, which performs important structural and regulatory functions.Conclusion. The use of sulodexide had a favorable effect on the studied metabolic disorders caused by a high-fat diet. It resulted in the normalization of the synthesis of laminin, one of the major non-collagen proteins of the extracellular matrix.
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Hesser, Anthony R., Kaitlin Schaefer, Wonsik Lee, and Suzanne Walker. "Lipoteichoic acid polymer length is determined by competition between free starter units." Proceedings of the National Academy of Sciences 117, no. 47 (November 10, 2020): 29669–76. http://dx.doi.org/10.1073/pnas.2008929117.
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Carbohydrate polymers exhibit incredible chemical and structural diversity, yet are produced by polymerases without a template to guide length and composition. As the length of carbohydrate polymers is critical for their biological functions, understanding the mechanisms that determine polymer length is an important area of investigation. Most Gram-positive bacteria produce anionic glycopolymers called lipoteichoic acids (LTA) that are synthesized by lipoteichoic acid synthase (LtaS) on a diglucosyl-diacylglycerol (Glc2DAG) starter unit embedded in the extracellular leaflet of the cell membrane. LtaS can use phosphatidylglycerol (PG) as an alternative starter unit, but PG-anchored LTA polymers are significantly longer, and cells that make these abnormally long polymers exhibit major defects in cell growth and division. To determine how LTA polymer length is controlled, we reconstitutedStaphylococcus aureusLtaS in vitro. We show that polymer length is an intrinsic property of LtaS that is directly regulated by the identity and concentration of lipid starter units. Polymerization is processive, and the overall reaction rate is substantially faster for the preferred Glc2DAG starter unit, yet the use of Glc2DAG leads to shorter polymers. We propose a simple mechanism to explain this surprising result: free starter units terminate polymerization by displacing the lipid anchor of the growing polymer from its binding site on the enzyme. Because LtaS is conserved across most Gram-positive bacteria and is important for survival, this reconstituted system should be useful for characterizing inhibitors of this key cell envelope enzyme.
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Leikina, Evgenia, Kamran Melikov, Sarmistha Sanyal, Santosh K. Verma, Bokkee Eun, Claudia Gebert, Karl Pfeifer, Vladimir A. Lizunov, Michael M. Kozlov, and Leonid V. Chernomordik. "Extracellular annexins and dynamin are important for sequential steps in myoblast fusion." Journal of Cell Biology 200, no. 1 (December 31, 2012): 109–23. http://dx.doi.org/10.1083/jcb.201207012.
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Myoblast fusion into multinucleated myotubes is a crucial step in skeletal muscle development and regeneration. Here, we accumulated murine myoblasts at the ready-to-fuse stage by blocking formation of early fusion intermediates with lysophosphatidylcholine. Lifting the block allowed us to explore a largely synchronized fusion. We found that initial merger of two cell membranes detected as lipid mixing involved extracellular annexins A1 and A5 acting in a functionally redundant manner. Subsequent stages of myoblast fusion depended on dynamin activity, phosphatidylinositol(4,5)bisphosphate content, and cell metabolism. Uncoupling fusion from preceding stages of myogenesis will help in the analysis of the interplay between protein machines that initiate and complete cell unification and in the identification of additional protein players controlling different fusion stages.
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Gupta, Madhu, Annabel Gameiro, and Pawan K. Singal. "Reduced vulnerability of the hypertrophied rat heart to oxygen-radical injury." Canadian Journal of Physiology and Pharmacology 65, no. 6 (June 1, 1987): 1157–64. http://dx.doi.org/10.1139/y87-183.
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Effects of xanthine – xanthine oxidase produced oxygen radicals were studied in hypertrophied rat hearts in a Langendorff preparation. Heart hypertrophy was produced by banding of the abdominal aorta for 6 weeks. This resulted in a 22% increase in ventricle/body weight ratio compared with that of sham-operated controls. Perfusion with xanthine – xanthine oxidase caused contractile failure and a significant rise in the resting tension. Complete contractile failure in hypertrophied hearts was seen at 25.5 ± 3.2 min, whereas in control hearts it happened at 14.4 ± 5.6 min. Contractile failure due to oxygen radicals in both groups was associated with a decline in high energy phosphates, increased lipid peroxidation, and extensive structural damage. Sarcolemma in both groups became permeable to the extracellular tracer lanthanum. As compared with control, in hypertrophied hearts the malondialdehyde content, indicative of lipid peroxidation, was less by 40%; whereas superoxide dismutase, a free radical scavenger, was higher by a similar amount. These data show a greater capacity of the 6-week hypertrophied heart to withstand a free radical induced contractile failure. This delay in oxygen radical effect can be partially explained by the reduced lipid peroxide content and increased superoxide dismutase activity in the hypertrophied hearts.
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Mazza, S., F. M. Accattatis, F. Bordonaro, A. Granata, L. Bianchi, F. Francomano, A. Carleo, et al. "Pharmacological modulation of lipid metabolism in a human cell line alters protein content and signalling of secreted extracellular vesicles." Atherosclerosis 355 (August 2022): 77. http://dx.doi.org/10.1016/j.atherosclerosis.2022.06.458.
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Beauséjour, Julie, Claudia Goyer, Joanne Vachon, and Carole Beaulieu. "Production of thaxtomin A by Streptomyces scabies strains in plant extract containing media." Canadian Journal of Microbiology 45, no. 9 (September 1, 1999): 764–68. http://dx.doi.org/10.1139/w99-072.
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Thaxtomin A production by Streptomyces scabies is induced by plant extracts in culture media. We compared the production of thaxtomin A by three Streptomyces scabies strains (EF-35, CG1, and ATCC 49173) in different culture media in a first attempt to identify the plant molecules required for the biosynthesis of thaxtomin A. Thaxtomin A production varied greatly among media and among S. scabies strains. Strain CG1 presented a higher production than the other strains in all complex media. Oat bran broth is the best thaxtomin A production medium, and suberin is the only plant polymer allowing the production of thaxtomin A in minimal medium. The three S. scabies strains had extracellular esterase activities when grown in the presence of potato suberin or oat bran. We suggest that extracellular esterases allow the release from lipid polymers of plant molecules that may act as inducers for thaxtomin A biosynthesis genes or as precursors in the biosynthetic pathway of thaxtomin A.Key words: common scab, phytotoxin, suberin, esterase.
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Suire, Caitlin N., and Mangesh D. Hade. "Extracellular Vesicles in Type 1 Diabetes: A Versatile Tool." Bioengineering 9, no. 3 (March 4, 2022): 105. http://dx.doi.org/10.3390/bioengineering9030105.
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Type 1 diabetes is a chronic autoimmune disease affecting nearly 35 million people. This disease develops as T-cells continually attack the β-cells of the islets of Langerhans in the pancreas, which leads to β-cell death, and steadily decreasing secretion of insulin. Lowered levels of insulin minimize the uptake of glucose into cells, thus putting the body in a hyperglycemic state. Despite significant progress in the understanding of the pathophysiology of this disease, there is a need for novel developments in the diagnostics and management of type 1 diabetes. Extracellular vesicles (EVs) are lipid-bound nanoparticles that contain diverse content from their cell of origin and can be used as a biomarker for both the onset of diabetes and transplantation rejection. Furthermore, vesicles can be loaded with therapeutic cargo and delivered in conjunction with a transplant to increase cell survival and long-term outcomes. Crucially, several studies have linked EVs and their cargos to the progression of type 1 diabetes. As a result, gaining a better understanding of EVs would help researchers better comprehend the utility of EVs in regulating and understanding type 1 diabetes. EVs are a composition of biologically active components such as nucleic acids, proteins, metabolites, and lipids that can be transported to particular cells/tissues through the blood system. Through their varied content, EVs can serve as a flexible aid in the diagnosis and management of type 1 diabetes. In this review, we provide an overview of existing knowledge about EVs. We also cover the role of EVs in the pathogenesis, detection, and treatment of type 1 diabetes and the function of EVs in pancreas and islet β-cell transplantation.
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Llamas, Sara, Eduardo Guzmán, Francisco Ortega, and Ramón G. Rubio. "Adsorption of Mixtures of a Pegylated Lipid with Anionic and Zwitterionic Surfactants at Solid/Liquid." Colloids and Interfaces 4, no. 4 (October 29, 2020): 47. http://dx.doi.org/10.3390/colloids4040047.
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This work explores the association of a pegylated lipid (DSPE-PEG) with different anionic and zwitterionic surfactants (pseudo-binary and pseudo-ternary polymer+ surfactant mixtures), and the adsorption of the polymer + surfactant aggregates onto negatively charged surfaces, with a surface charge density similar to that existing on the damaged hair epicuticle. Dynamic light scattering and zeta potential measurements shows that, in solution, the polymer + surfactant association results from an intricate balance between electrostatic and hydrophobic interactions, which leads to the formation of at least two different types of micellar-like polymer + surfactant aggregates. The structure and physicochemical properties of such aggregates were found strongly dependent on the specific nature and concentration of the surfactant. The adsorption of the polymer + surfactant aggregates onto negatively charged surface was studied using a set of surface-sensitive techniques (quartz crystal microbalance with dissipation monitoring, ellipsometry and Atomic Force Microscopy), which allows obtaining information about the adsorbed amount, the water content of the layers and the topography of the obtained films. Ion-dipole interactions between the negative charges of the surface and the oxyethylene groups of the polymer + surfactant aggregates appear as the main driving force of the deposition process. This is strongly dependent on the surfactant nature and its concentration, with the impact of the latter on the adsorption being especially critical when anionic surfactant are incorporated within the aggregates. This study opens important perspectives for modulating the deposition of a poorly interacting polymer onto negatively charged surfaces, which can impact in the fabrication on different aspects with technological and industrial interest.
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Stoneham, Susanna, Tuula Kiviluoto, Leila Keso, and Jorma J. Ohisalo. "Adenosine and the regional differences in adipose tissue metabolism in women." Acta Endocrinologica 118, no. 3 (July 1988): 327–31. http://dx.doi.org/10.1530/acta.0.1180327.
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Abstract. Adenosine content in abdominal and femoral adipose tissue in menstruating women was 0.38 ± 0.10 and 0.59 ± 0.14 nmol/g of wet weight, respectively (mean ± sem; N = 17). No difference in adenosine sensitivity was found between abdominal and femoral adipocytes. In lactating women, the adenosine content was lower in femoral than in abdominal adipose tissue (0.40 ± 0.08 and 0.57 ± 0.08 nmol/g of wet weight, respectively; N = 10). Adenosine sensitivity in femoral adipocytes was not increased during lactation. As adenosine is a locally acting insulin-like effector, these results suggest that the higher adenosine content in femoral adipose tissue in menstruating women could explain its higher lipoprotein lipase activity and tendency to accumulate fat. During lactation, the lower extracellular adenosine concentration would allow lipid mobilization preferentially from the femoral site.
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Matsuzaka, Yasunari, and Ryu Yashiro. "Therapeutic Strategy of Mesenchymal-Stem-Cell-Derived Extracellular Vesicles as Regenerative Medicine." International Journal of Molecular Sciences 23, no. 12 (June 9, 2022): 6480. http://dx.doi.org/10.3390/ijms23126480.
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Extracellular vesicles (EVs) are lipid bilayer membrane particles that play critical roles in intracellular communication through EV-encapsulated informative content, including proteins, lipids, and nucleic acids. Mesenchymal stem cells (MSCs) are pluripotent stem cells with self-renewal ability derived from bone marrow, fat, umbilical cord, menstruation blood, pulp, etc., which they use to induce tissue regeneration by their direct recruitment into injured tissues, including the heart, liver, lung, kidney, etc., or secreting factors, such as vascular endothelial growth factor or insulin-like growth factor. Recently, MSC-derived EVs have been shown to have regenerative effects against various diseases, partially due to the post-transcriptional regulation of target genes by miRNAs. Furthermore, EVs have garnered attention as novel drug delivery systems, because they can specially encapsulate various target molecules. In this review, we summarize the regenerative effects and molecular mechanisms of MSC-derived EVs.
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Giusti, Ilaria, and Vincenza Dolo. "Extracellular Vesicles in Prostate Cancer: New Future Clinical Strategies?" BioMed Research International 2014 (2014): 1–14. http://dx.doi.org/10.1155/2014/561571.
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Prostate cancer (PCa) is the most common cancer—excluding skin tumors—in men older than 50 years of age. Over time, the ability to diagnose PCa has improved considerably, mainly due to the introduction of prostate-specific antigen (PSA) in the clinical routine. However, it is important to take into account that although PSA is a highly organ-specific marker, it is not cancer-specific. This shortcoming suggests the need to find new and more specific molecular markers. Several emerging PCa biomarkers have been evaluated or are being assessed for their potential use. There is increasing interest in the prospective use of extracellular vesicles as specific markers; it is well known that the content of vesicles is dependent on their cellular origin and is strongly related to the stimulus that triggers the release of the vesicles. Consequently, the identification of a disease-specific molecule (protein, lipid or RNA) associated with vesicles could facilitate their use as novel biological markers. The present review describes severalin vitrostudies that demonstrate the role of vesicles in PCa progression and severalin vivostudies that highlight the potential use of vesicles as PCa biomarkers.
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Andrews, John H., Robin F. Harris, Russell N. Spear, Gee W. Lau, and Erik V. Nordheim. "Morphogenesis and adhesion of Aureobasidium pullulans." Canadian Journal of Microbiology 40, no. 1 (January 1, 1994): 6–17. http://dx.doi.org/10.1139/m94-002.
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Two strains of the dimorphic fungus Aureobasidium pullulans were grown in liquid and on solid media varying in carbon and nitrogen content, and on leaf surfaces. Hyphae were observed in all systems but comprised a very low proportion (often below quantitative detection) of the total biomass. In liquid media, hyphae were found sparsely and only in the wash-zone on walls of the culture flasks. Yeast phase growth (blastospores) occurred in pH-buffered media that were nutrient balanced, or continuously carbon-limited (fed-batch culture), or carbon-exhausted (batch culture). Blastospores exposed to conditions with limited nitrogen but sufficient organic carbon, or to acidified media, converted to swollen cells and chlamydospores. The latter morphotypes accumulated carbon internally as lipid granules, and then externally as capsular and soluble extracellular polysaccharide. They were cohesive and also adhered more strongly to cellulose membranes overlying agar media or to leaves than did blastospores. Pullulanase treatment diminished the capsules, cohesion, and adhesion. Addition of soluble extracellular polysaccharide to blastospores enhanced their adhesion to leaves. We conclude that extracellular polysaccharide can play a role in adhesion of A. pullulans.Key words: phylloplane, leaf surface, epiphytic growth, extracellular polysaccharide, cell attachment.