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Sample records for vesicle sodium na-dependent

  1. Expression and regulation of Na-dependent P(i) transport in matrix vesicles produced by osteoblast-like cells.

    Science.gov (United States)

    Montessuit, C; Bonjour, J P; Caverzasio, J

    1995-04-01

    Extracellular matrix vesicles (MV) are the loci of initial mineralization in several calcifying tissues. We recently reported that MV isolated from chicken epiphyseal cartilage are equipped with a Na-dependent P(i) transport (NaPiT) system. The activity of the NaPiT system appeared to be crucial for the development of MV-mediated calcification. In the present study we investigated the expression of NaPiT activity in MV produced by the osteoblast-like cells MC3T3-E1. The relationship between changes in NaPiT activity in the intact cells and in the released MV was also examined. NaPiT activity in MV harvested from cultured MC3T3-E1 cells was transiently expressed. It was markedly increased between Days 8 and 10 (5- to 6-fold), and then gradually decreased. NaPiT activity was enriched in MV as compared with the parent osteoblast-like cells, while the Na-dependent transport system for alanine (NaAlaT) was not. When NaPiT activity was enhanced in osteoblast-like cells by fetal calf serum (FCS) or P(i) depletion, P(i) transport stimulation was observed in the derived MV as well. Alkaline phosphatase (AP) was differentially expressed and regulated in MV from MC3T3-E1 cell cultures, as compared with NaPiT. In contrast to the transient expression of NaPiT, AP activity in MV increased continuously with time in culture. It was stimulated by FCS treatment of the parent cells, but decreased in MV obtained from P(i)-depleted cultures. These results suggest that the presence in osteogenic cells of selective regulatory mechanisms for the insertion and enrichment of P(i) transport activity in released MV.(ABSTRACT TRUNCATED AT 250 WORDS)

  2. Effect of sodium deoxycholate and sodium cholate on DPPC vesicles

    Indian Academy of Sciences (India)

    TECS

    monitor different stages of interaction of bile salts with DPPC vesicles. NaDC induced significant changes in the ... more hydrophilic NaC does not interact with the membrane efficiently. Complete solubilisation of phos- pholipids .... the temperature was controlled by circulating water through a jacketted cuvette holder from a ...

  3. SODIUM ION-DEPENDENT AMINO-ACID-TRANSPORT IN MEMBRANE-VESICLES OF BACILLUS-STEAROTHERMOPHILUS

    NARCIS (Netherlands)

    HEYNE, RIR; DEVRIJ, W; CRIELAARD, W; KONINGS, WN

    Amino acid transport in membrane vesicles of Bacillus stearothermophilus was studied. A relatively high concentration of sodium ions is needed for uptake of L-alanine (K(t) = 1.0 mM) and L-leucine (K(t) = 0.4 mM). In contrast, the Na+-H+-L-glutamate transport system has a high affinity for sodium

  4. Sodium-stimulated glutamate transport in osmotically shocked cells and membrane vesicles of Escherichia coli.

    Science.gov (United States)

    Miner, K M; Frank, L

    1974-03-01

    Three phenotypically distinct strains of Escherichia coli B were studied: one in which the transport of glutamate was strongly stimulated by sodium, one in which the transport was relatively independent of sodium, and one which did not transport glutamate. Membrane vesicle preparations from the three strains followed the behavior of whole cells with respect to sodium-stimulated transport. Although glutamate-binding material could be released from cells by osmotic shock, its affinity for glutamate was not significantly influenced by sodium. Furthermore, the shocked cells retained sodium-stimulated transport. The accumulated results suggest that the sodium-activated glutamate transport system resides in the cytoplasmic membrane and that releasable binding protein(s) is not intimately involved in its function.

  5. Light-induced DELTApH and DELTApsi in halobacterial vesicles related to sodium transport

    Energy Technology Data Exchange (ETDEWEB)

    Kamo, N.; Racanclli, T.; Packer, L.

    1986-01-01

    Membranes of Halobacterium halobium contain two retinoproteins, baceteriorhodopsin (BR/sub 568nm/) and halorhodopsin (HR/sub 588nm/). We have investigated the light- and sodium-dependent activities in vesicles from the HR containing R/sub 1/mR strain, and the BR + HR containing S/sub 9/ strain to study energy conversion and ion flow mechanisms. Simultaneous ..delta..pH and ..delta..psi measurements have been made with electrodes. In R/sub 1/mR vesicles, -..delta..psi and H/sup +/ uptake occurs in NaCl but not in KCl medium. In S/sub 9/ vesicles, net H/sup +/ extrusion is reduced at high light intensity in NaCl but not KCl medium. Such results indicate Na/sup +//H/sup +/ exchange in vesicles from both strains. As S/sub 9/ contains BR + HR, it is unclear whether the Na/sup +/ extrusion is due to a Na/sup +//H/sup +/ antiporter and/or HR which has been proposed to be a light driven Na/sup +/ pump. To evaluate these concepts for Na/sup +/ transport, the light intensity dependence and action of several membrane transport active agents have been compared. Digitoxin, electro-neutral exchangers (triphenyltin and monensin), and phloretin yielded similar results for HR (R/sub 1/mR) and HR + BR (S/sub 9/) vesicles. Moreover treatment of vesicles with carboxyl reacting reagents inhibited Na/sup +/ dependent activity in both types of vesicles. Thus, common mechanisms of Na/sup +/ transport are indicated in S/sub 9/ and R/sub 1/mR vesicles. 22 refs., 9 figs., 1 tab.

  6. Sophocarpine attenuates the Na(+)-dependent Ca2(+) overload induced by Anemonia sulcata toxin-increased late sodium current in rabbit ventricular myocytes.

    Science.gov (United States)

    Zhang, Shuo; Ma, Ji-Hua; Zhang, Pei-Hua; Luo, An-Tao; Ren, Zhi-Qiang; Kong, Ling-Hao

    2012-10-01

    Many studies indicate that an increase in late sodium current (I(Na.L)) of cardiomyocytes causes intracellular Na overload and subsequently raises the reverse Na/Ca exchanger current (INCX), ultimately resulting in intracellular Ca overload. Therefore, using drugs to inhibit the increased INa.L under various pathological conditions can lower intracellular Ca overload. This study was intended to explore the effect of sophocarpine (SOP) on the increase in INa.L, INCX, calcium transient and contraction in rabbit ventricular myocytes induced by Anemonia sulcata toxin II (ATX II), an opener of sodium channel, with the application of whole-cell patch-clamp techniques, the video-based motion edge detection system, and the intracellular calcium concentration determination system. The results indicate that tetrodotoxin (TTX, 4 μM ) obviously decreased INa.L and INCX enlarged by ATX II (30 nM), and SOP (20, 40, and 80 μM) also inhibited both the parameters concentration dependently in rabbit ventricular myocytes. However, transient sodium current remained unaffected by the above-mentioned concentrations of ATX II, TTX, and SOP. In addition, SOP also reversed diastolic calcium concentration, calcium transient amplitude, and ventricular muscle contractility augmented by ATX II. Its effects were similar to those of TTX, a specific inhibitor of the sodium channel. In conclusion, SOP inhibits INa.L, INCX, diastolic Ca concentration, and contractility in rabbit ventricular myocytes, which suggests that relief of intracellular Ca overload through inhibiting INa.L is likely to become a new therapeutic mechanism of SOP against arrhythmia and myocyte damage associated with intracellular Ca overload.

  7. Vesicle formation and stability in the surfactant sodium 4-(1'-heptylnonyl) benzenesulfonate

    Energy Technology Data Exchange (ETDEWEB)

    Franses, E.I.; Talmon, Y.; Scriven, L.E.; Davis, H.T.; Miller, W.G.

    1982-04-01

    Surfactants composed of a hydrophilic moiety covalently attached to the end of a hydrocarbon chain (e.g., sodium dodecyl sulfate), spontaneously form micelles, equilibrium aggregates, in solution if the surfactant concentration exceeds a critical value called the CMC. Naturally occurring double-tail surfactants (e.g., phospholipids) are not known to form micelles. Over a considerable range in surfactant concentration, 2 phases coexist in equilibrium: a hydrated, multilamellar (smectic) surfactant phase and an aqueous phase saturated with surfactant. In this report the preparation of vesicles, their direct, unstained visualization by electron microscopy, and investigation of their stability and structure by turbidimetry, conductimetry, light microscopy, densitometry, scanning calorimetry, and nuclear magnetic resonance spectroscopy are discussed. Dispersed liquid crystal was studied by the same means. For comparison, parallel studies on bovine lecithin are presented. From the results, it is concluded that these vesicles may be stable for many months, but eventually revert to multilamellar liquid crystals.

  8. Light-dependent delta pH and membrane potential changes in halobacterial vesicles coupled to sodium transport

    Energy Technology Data Exchange (ETDEWEB)

    Kamo, N.; Racanelli, T.; Packer, L.

    1982-01-01

    Bacteriorhodopsin and Halorhodopsin present in Halobacterium halobium strains have been investigated in relation to Na/sup +//H/sup +/ exchange in isolated cell envelope vesicles. Upon illumination, these retinal proteins result in extrusion of sodium ions by either an electrogenic Na/sup +//Ha/sup +/ antiporter and/or a direct sodium pump. Since a molecular characterization of these mechanism(s) of sodium extrusion has not yet been realized, it was of interest to measure directly the light- and sodium-dependent changes in delta pH and membrane potential under nearly identical conditions in S9 and R1mR cell membrane vesicles to gain information on the relation of these retinal proteins to sodium extrusion. These activities were evaluated in terms of their dependence on light intensity, and on the inhibitory effect of chemical modifiers of carboxyl groups (carbodiimides); electroneutral exchanges (monensin and triphenyltin); digitoxin and some analogues; and phloretin. Under most of the conditions and treatments employed, light- and sodium-dependent delta pH led to similar effects in both membrane vesicle types. Hence, it is concluded that the delta pH and delta psi which arise from sodium transport occur by either a single mechanism or by one which shares common features.

  9. Sodium dodecyl sulfate/β-cyclodextrin vesicles embedded in chitosan gel for insulin delivery with pH-selective release

    Directory of Open Access Journals (Sweden)

    Zhuo Li

    2016-07-01

    Full Text Available In an answer to the challenge of enzymatic instability and low oral bioavailability of proteins/peptides, a new type of drug-delivery vesicle has been developed. The preparation, based on sodium dodecyl sulfate (SDS and β-cyclodextrin (β-CD embedded in chitosan gel, was used to successfully deliver the model drug-insulin. The self-assembled SDS/β-CD vesicles were prepared and characterized by particle size, zeta potential, appearance, microscopic morphology and entrapment efficiency. In addition, both the interaction of insulin with vesicles and the stability of insulin loaded in vesicles in the presence of pepsin were investigated. The vesicles were crosslinked into thermo-sensitive chitosan/β-glycerol phosphate solution for an in-situ gel to enhance the dilution stability. The in vitro release characteristics of insulin from gels in media at different pH values were investigated. The insulin loaded vesicles–chitosan hydrogel (IVG improved the dilution stability of the vesicles and provided pH-selective sustained release compared with insulin solution–chitosan hydrogel (ISG. In vitro, IVG exhibited slow release in acidic solution and relatively quick release in neutral solutions to provide drug efficacy. In simulated digestive fluid, IVG showed better sustained release and insulin protection properties compared with ISG. Thus IVG might improve the stability of insulin during its transport in vivo and contribute to the bioavailability and therapeutic effect of insulin.

  10. Ternary phase behaviour and vesicle formation of a sodium N-lauroylsarcosinate hydrate/1-decanol/water system

    Science.gov (United States)

    Akter, Nasima; Radiman, Shahidan; Mohamed, Faizal; Rahman, Irman Abdul; Reza, Mohammad Imam Hasan

    2011-08-01

    The phase behaviour of a system composed of amino acid-based surfactant (sodium N-lauroylsarcosinate hydrate), 1-decanol and deionised water was investigated for vesicle formation. Changing the molar ratio of the amphiphiles, two important aggregate structures were observed in the aqueous corner of the phase diagram. Two different sizes of microemulsions were found at two amphiphile-water boundaries. A stable single vesicle lobe was found for 1∶2 molar ratios in 92 wt% water with vesicles approximately 100 nm in size and with high zeta potential value. Structural variation arises due to the reduction of electrostatic repulsions among the ionic headgroups of the surfactants and the hydration forces due to adsorbed water onto monolayer's. The balance of these two forces determines the aggregate structures. Analysis was followed by the molecular geometrical structure. These findings may have implications for the development of drug delivery systems for cancer treatments, as well as cosmetic and food formulations.

  11. Thermodynamics and Structural Evolution during a Reversible Vesicle-Micelle Transition of a Vitamin-Derived Bolaamphiphile Induced by Sodium Cholate.

    Science.gov (United States)

    Tian, Jun-Nan; Ge, Bing-Qiang; Shen, Yun-Feng; He, Yu-Xuan; Chen, Zhong-Xiu

    2016-03-09

    Interaction of endogenous sodium cholate (SC) with dietary amphiphiles would induce structural evolution of the self-assembled aggregates, which inevitably affects the hydrolysis of fat in the gut. Current work mainly focused on the interaction of bile salts with classical double-layered phospholipid vesicles. In this paper, the thermodynamics and structural evolution during the interaction of SC with novel unilamellar vesicles formed from vitamin-derived zwitterionic bolaamphiphile (DDO) were characterized. It was revealed that an increased temperature and the presence of NaCl resulted in narrowed micelle-vesicle coexistence and enlarged the vesicle region. The coexistence of micelles and vesicles mainly came from the interaction of monomeric SC with DDO vesicles, whereas micellar SC contributed to the total solubilization of DDO vesicles. This research may enrich the thermodynamic mechanism behind the structure transition of the microaggregates formed by amphiphiles in the gut. It will also contribute to the design of food formulation and drug delivery system.

  12. SODIUM DI-N-DODECYLPHOSPHATE VESICLES IN AQUEOUS-SOLUTION - EFFECTS OF ADDED ETHANOL, AND CA2+ AND NA+ IONS ON THE GEL LIQUID-PHASE TRANSITION

    NARCIS (Netherlands)

    BLANDAMER, MJ; BRIGGS, B; CULLIS, PM; ENGBERTS, JBFN; HOEKSTRA, D

    1994-01-01

    For aqueous solutions containing vesicles formed by sodium di-n-dodecylphosphate, the gel-liquid-crystal transition occurs near 35-degrees-C at the temperature T(m). When ethanol is added, T(m) decreases. When sodium chloride is added, T(m) shifts to higher temperatures whereas very complex scans

  13. Extracellular vesicles derived from gut microbiota, especially Akkermansia muciniphila, protect the progression of dextran sulfate sodium-induced colitis.

    Directory of Open Access Journals (Sweden)

    Chil-Sung Kang

    Full Text Available Gut microbiota play an important part in the pathogenesis of mucosal inflammation, such as inflammatory bowel disease (IBD. However, owing to the complexity of the gut microbiota, our understanding of the roles of commensal and pathogenic bacteria in the maintenance of immune homeostasis in the gut is evolving only slowly. Here, we evaluated the role of gut microbiota and their secreting extracellular vesicles (EV in the development of mucosal inflammation in the gut. Experimental IBD model was established by oral application of dextran sulfate sodium (DSS to C57BL/6 mice. The composition of gut microbiota and bacteria-derived EV in stools was evaluated by metagenome sequencing using bacterial common primer of 16S rDNA. Metagenomics in the IBD mouse model showed that the change in stool EV composition was more drastic, compared to the change of bacterial composition. Oral DSS application decreased the composition of EV from Akkermansia muciniphila and Bacteroides acidifaciens in stools, whereas increased EV from TM7 phylum, especially from species DQ777900_s and AJ400239_s. In vitro pretreatment of A. muciniphila-derived EV ameliorated the production of a pro-inflammatory cytokine IL-6 from colon epithelial cells induced by Escherichia coli EV. Additionally, oral application of A. muciniphila EV also protected DSS-induced IBD phenotypes, such as body weight loss, colon length, and inflammatory cell infiltration of colon wall. Our data provides insight into the role of gut microbiota-derived EV in regulation of intestinal immunity and homeostasis, and A. muciniphila-derived EV have protective effects in the development of DSS-induced colitis.

  14. Early induction of Na(+)-dependent uridine uptake in the regenerating rat liver.

    Science.gov (United States)

    Ruiz-Montasell, B; Martinez-Mas, J V; Enrich, C; Casado, F J; Felipe, A; Pastor-Anglada, M

    1993-01-18

    Na(+)-dependent uridine transport into liver plasma membrane vesicles from partially hepatectomized and sham-operated rats was studied. Preparations purified 6 h after 70% hepatectomy exhibited an increased Vmax of uridine uptake (3.7 vs. 1.4 pmol/mg prot/3 s) without any change in Km (6 microM). Incubation of the vesicles in the presence of monensin decreased uridine uptake although the differences between both experimental groups remained identical. It is concluded that uridine transport is induced early after partial hepatectomy by a mechanism which does not involve changes in the transmembrane Na+ gradient. This is the first evidence in favor of modulation of nucleoside transport into liver cells.

  15. Sodium

    Science.gov (United States)

    Table salt is a combination of two minerals - sodium and chloride Your body needs some sodium to work properly. It helps with the function ... in your body. Your kidneys control how much sodium is in your body. If you have too ...

  16. Sodium-Dependent Transport of Neutral Amino Acids by Whole Cells and Membrane Vesicles of Streptococcus bovis, a Ruminal Bacterium

    NARCIS (Netherlands)

    Russell, James B.; Strobel, Herbert J.; Driessen, Arnold J.M.; Konings, Wilhelmus

    Streptococcus bovis JB1 cells were able to transport serine, threonine, or alanine, but only when they were incubated in sodium buffers. If glucose-energized cells were washed in potassium phosphate and suspended in potassium phosphate buffer, there was no detectable uptake. Cells deenergized with

  17. Vesicle Photonics

    Science.gov (United States)

    Vasdekis, A. E.; Scott, E. A.; Roke, S.; Hubbell, J. A.; Psaltis, D.

    2013-07-01

    Amphiphiles, under appropriate conditions, can self-assemble into nanoscale thin membrane vessels (vesicles) that encapsulate and hence protect and transport molecular payloads. Vesicles assemble naturally within cells but can also be artificially synthesized. In this article, we review the mechanisms and applications of light-field interactions with vesicles. By being associated with light-emitting entities (e.g., dyes, fluorescent proteins, or quantum dots), vesicles can act as imaging agents in addition to cargo carriers. Vesicles can also be optically probed on the basis of their nonlinear response, typically from the vesicle membrane. Light fields can be employed to transport vesicles by using optical tweezers (photon momentum) or can directly perturb the stability of vesicles and hence trigger the delivery of the encapsulated payload (photon energy). We conclude with emerging vesicle applications in biology and photochemical microreactors.

  18. Effect of sodium deoxycholate and sodium cholate on DPPC ...

    Indian Academy of Sciences (India)

    Effects of two bile salts, namely sodium deoxycholate (NaDC) and sodium cholate (NaC), on DPPC small unilamellar vesicles have been investigated using the steady-state fluorescence anisotropy () of diphenylhexatriene (DPH) as a tool. It was found that the variation of is sensitive enough to monitor different ...

  19. Synaptic Vesicle Endocytosis

    Science.gov (United States)

    Saheki, Yasunori; De Camilli, Pietro

    2012-01-01

    Neurons can sustain high rates of synaptic transmission without exhausting their supply of synaptic vesicles. This property relies on a highly efficient local endocytic recycling of synaptic vesicle membranes, which can be reused for hundreds, possibly thousands, of exo-endocytic cycles. Morphological, physiological, molecular, and genetic studies over the last four decades have provided insight into the membrane traffic reactions that govern this recycling and its regulation. These studies have shown that synaptic vesicle endocytosis capitalizes on fundamental and general endocytic mechanisms but also involves neuron-specific adaptations of such mechanisms. Thus, investigations of these processes have advanced not only the field of synaptic transmission but also, more generally, the field of endocytosis. This article summarizes current information on synaptic vesicle endocytosis with an emphasis on the underlying molecular mechanisms and with a special focus on clathrin-mediated endocytosis, the predominant pathway of synaptic vesicle protein internalization. PMID:22763746

  20. Preparation of large monodisperse vesicles.

    Directory of Open Access Journals (Sweden)

    Ting F Zhu

    Full Text Available Preparation of monodisperse vesicles is important both for research purposes and for practical applications. While the extrusion of vesicles through small pores (approximately 100 nm in diameter results in relatively uniform populations of vesicles, extrusion to larger sizes results in very heterogeneous populations of vesicles. Here we report a simple method for preparing large monodisperse multilamellar vesicles through a combination of extrusion and large-pore dialysis. For example, extrusion of polydisperse vesicles through 5-microm-diameter pores eliminates vesicles larger than 5 microm in diameter. Dialysis of extruded vesicles against 3-microm-pore-size polycarbonate membranes eliminates vesicles smaller than 3 microm in diameter, leaving behind a population of monodisperse vesicles with a mean diameter of approximately 4 microm. The simplicity of this method makes it an effective tool for laboratory vesicle preparation with potential applications in preparing large monodisperse liposomes for drug delivery.

  1. Fusion of Nonionic Vesicles

    DEFF Research Database (Denmark)

    Bulut, Sanja; Oskolkova, M. Z.; Schweins, R.

    2010-01-01

    We present an experimental study of vesicle fusion using light and neutron scattering to monitor fusion events. Vesicles are reproducibly formed with an extrusion procedure using an single amphiphile triethylene glycol mono-n-decyl ether in water. They show long-term stability for temperatures ar...... a barrier to fusion changing from 15 k(B)T at T = 26 degrees C to 10k(H) T at T = 35 degrees C. These results are compatible with the theoretical predictions using the stalk model of vesicle fusion....

  2. Biochemical and morphological characterization of light and heavy sarcoplasmic reticulum vesicles. Volume I

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, Kevin Peter [Univ. of Rochester, NY (United States)

    1978-01-01

    Light (30 to 32.5% sucrose) and heavy (38.5 to 42% sucrose) sarcoplasmic reticulum vesicles (LSR, HSR) were isolated from rabbit leg muscle. They were then diluted and washed with sucrose or KCl and referred to as sucrose or KCl washed vesicles. Thin-section electron microscopy of LSR vesicles reveals empty vesicles of various sizes and shapes where as the HSR vesicles appear as rounded vesicles of uniform size filled with electron dense material. The LSR consists of predominantly Ca2+ + Mg2+ ATPase (80 to 90%), a small amount of the high affinity Ca binding protein (5%), and a 5000 dalton proteolipid. The sucrose HSR vesicles contain the Ca2+ + Mg2+ ATPase (50%), Calsequestrin (25%), high affinity Ca binding protein (5%), one extrinsic 34,000 dalton protein (3%), one intrinsic 30,000 dalton protein (3%), a 9000 dalton proteolipid, and a 5000 dalton proteolipid. The sucrose--washed HSR vesicles contain greater than three times the calcium content of the sucrose washed LSR vesicles where as the KCl--washed vesicles contain less than 15 nmoles Ca2+ mg of protein each. The light and heavy sarcoplasmic reticulum vesicles were both able to accumulate calcium in the presence of ATP. Exchange of methanesulfonate for chloride resulted in the release of calcium from both the light and heavy SR vesicles. Sucrose causes a slight inhibition of chloride--induced calcium release from the heavy SR vesicles but it greatly reduces the release of calcium from the light SR vesicles. Sodium dantrolene (20 uM) has no effect on the release of calcium from the light SR vesicles but it inhibits the release of calcium from the heavy SR vesicles. The results indicate that the chloride--induced release of calcium may be acting by two mechanisms, osmotic swelling and depolarization.

  3. Kinetic properties and Na+ dependence of rheogenic Na(+)-HCO3- co-transport in frog retinal pigment epithelium.

    Science.gov (United States)

    la Cour, M

    1991-01-01

    1. Na(+)-HCO3- co-transport across the retinal membrane of the frog retinal pigment epithelium was studied by means of double-barrelled pH-selective microelectrodes. Transient changes in the intracellular pH were monitored in response to abrupt changes in the Na+ concentration on the retinal side of the epithelium. 2. The experiments were performed as follows. The Na(+)-HCO3- co-transport was inhibited by perfusing the retinal side of the epithelium with a Na(+)-free solution. The co-transport was then stimulated by changing the perfusate from the Na(+)-free solution to a solution which contained from 5 to 110 mM-Na+. The resulting inward Na(+)-HCO3- co-transport produced an intracellular alkalinization, the initial rate of which was used to calculate the initial rate of Na(+)-HCO3- co-transport, JHCO3-. 3. The Na+ dependence of the Na(+)-HCO3- co-transport was studied at two different values of extracellular pH (7.40 and 7.10), at constant extracellular HCO3- concentration (27.5 mM) and at two different extracellular HCO3- concentrations (27.5 mM and 55 mM) at constant extracellular pH (7.40). In these experiments, the calculated values of JHCO3- followed single Michaelis-Menten kinetics with respect to the extracellular Na+ concentration. 4. The data are consistent with a model in which the co-transporter has a single binding site for the Na+ ion with an apparent affinity constant (apparent Km) of 37 mM. The apparent affinity constant for Na+ was independent of the extracellular concentration of CO3(2-) in the range of 16-65 microM, and of the extracellular HCO3- concentration in the range 27.5-55 mM. 5. The NaCO3- ion-pair hypothesis, in which sodium binds to the co-transporter and is translocated across the cell membrane as the NaCO3- ion pair, was analysed. For stoichiometries 1:2 and 1:3 of the Na(+)-HCO3- co-transport, the NaCO3- ion-pair hypothesis was found incompatible with the data. 6. The intracellular buffer capacity as measured by the CO2 method was

  4. How pure are your vesicles?

    Science.gov (United States)

    Webber, Jason; Clayton, Aled

    2013-01-01

    We propose a straightforward method to estimate the purity of vesicle preparations by comparing the ratio of nano-vesicle counts to protein concentration, using tools such as the increasingly available NanoSight platform and a colorimetric protein assay such as the BCA-assay. Such an approach is simple enough to apply to every vesicle preparation within a given laboratory, assisting researchers as a routine quality control step. Also, the approach may aid in comparing/standardising vesicle purity across diverse studies, and may be of particular importance in evaluating vesicular biomarkers. We herein propose some criteria to aid in the definition of pure vesicles. PMID:24009896

  5. Effect of surfactant counterion and organic modifier on the properties of surfactant vesicles in electrokinetic chromatography.

    Science.gov (United States)

    Schuster, Stephanie A; Foley, Joe P

    2005-08-01

    Counterion and organic modifier are two parameters in EKC that can be varied in order to obtain improved solubility, selectivity, and efficiency. The effect of changing surfactant counterion and/or organic modifier on the chromatographic and electrophoretic properties of cetyltrimethylammonium bromide (CTAB)/sodium octyl sulfate (SOS) vesicles is examined in EKC. The vesicles are prepared in a 1:3.66 cationic/ anionic mole ratio for a total surfactant concentration of 69 mM. The cationic CTAB is replaced by cetyltrimethylammonium chloride (CTAC) and the first use of CTAC/SOS vesicles is reported. The mean diameter of the CTAC/SOS vesicles is 96 nm while that of the CTAB/SOS vesicles is 85 nm. A class I modifier (2-amino-1-butanol) and a class II modifier (acetonitrile) have similar effects on the EOF, elution range, methylene selectivity, and the efficiency of the CTAB/SOS vesicles and the CTAC/SOS vesicles. Upon addition of 10% ACN, there is roughly a 10-fold increase in the efficiency of heptanophenone, a model hydrophobic compound, compared to the efficiency using unmodified vesicles. Linear free energy relationship (LFER) analysis using the Abraham solvation model is employed to characterize solute-vesicle interactions. The results suggest that organic modifier-vesicle interactions depend somewhat on the counterion.

  6. Mechanism of the Association between Na+ Binding and Conformations at the Intracellular Gate in Neurotransmitter:Sodium Symporters

    DEFF Research Database (Denmark)

    Stolzenberg, Sebastian; Quick, Matthias; Zhao, Chunfeng

    2015-01-01

    Neurotransmitter:sodium symporters (NSSs) terminate neurotransmission by Na+-dependent reuptake of released neurotransmitters. Previous studies suggested that Na+-binding reconfigures dynamically coupled structural elements in an allosteric interaction network (AIN) responsible for function-relat...

  7. Kemp elimination in membrane mimetic reaction media : Probing catalytic properties of catanionic vesicles formed from double-tailed amphiphiles

    NARCIS (Netherlands)

    Klijn, J.E.; Engberts, J.B.F.N.

    2003-01-01

    The rate-determining deprotonation of 5-nitrobenzisoxazole (Kemp elimination) by hydroxide is efficiently catalyzed by vesicles formed from dimethyldioctadecylammonium chloride (C18C18+). Gradual addition of sodium didecyl phosphate (C10C10-) leads to the formation of catanionic vesicles, which were

  8. ENTHALPIES OF INTERACTION BETWEEN DIMETHYLDIOCTADECYLAMMONIUM BROMIDE VESICLES IN AQUEOUS-SOLUTION AND EITHER DIPICOLINATE OR SULFATE ANIONS

    NARCIS (Netherlands)

    BLANDAMER, MJ; BRIGGS, B; BUTT, MD; CULLIS, PM; WATERS, M; ENGBERTS, JBFN; HOEKSTRA, D

    1994-01-01

    Injection of small aliquots of dipicolinate anions (sodium salt) into an aqueous solution containing dimethyldioctadecylammonium bromide (DOAB) vesicles is endothermic at 50-degrees-C, becoming first more and then less endothermic. The injection process is effectively athermal for solutions

  9. The toolbox of vesicle sidedness determination

    NARCIS (Netherlands)

    Meszaros, Peter; Hoekstra, Dick; Kok, Jan Willem

    2012-01-01

    Vesicles prepared from cellular plasma membranes are widely used in science for different purposes. The outer membrane leaflet differs from the inner membrane leaflet of the vesicle, and during vesicle preparation procedures two types of vesicles will be generated: right-side-out vesicles, of which

  10. Vesicles and vesicle gels - structure and dynamics of formation

    CERN Document Server

    Gradzielski, M

    2003-01-01

    Vesicles constitute an interesting morphology formed by self-aggregating amphiphilic molecules. They exhibit a rich structural variety and are of interest both from a fundamental point of view (for studying closed bilayer systems) and from a practical point of view (whenever one is interested in the encapsulation of active molecules). In many circumstances vesicular structures have to be formed by external forces, but of great interest are amphiphilic systems, where they form spontaneously. Here the question arises of whether this means that they are also thermodynamically stable structures, which at least in some systems appears to be the case. If such vesicles are well defined in size, it is possible to pack them densely and thereby form vesicle gels that possess highly elastic properties even for relatively low volume fractions of amphiphile. Conditions for the formation and the microstructure of such vesicle gels have been studied in some detail for the case of unilamellar vesicles. Another important and ...

  11. Preeclampsia and Extracellular Vesicles.

    Science.gov (United States)

    Gilani, Sarwat I; Weissgerber, Tracey L; Garovic, Vesna D; Jayachandran, Muthuvel

    2016-09-01

    Preeclampsia is a hypertensive pregnancy disorder characterized by development of hypertension and proteinuria after 20 weeks of gestation that remains a leading cause of maternal and neonatal morbidity and mortality. While preeclampsia is believed to result from complex interactions between maternal and placental factors, the proximate pathophysiology of this syndrome remains elusive. Cell-to-cell communication is a critical signaling mechanism for feto-placental development in normal pregnancies. One mechanism of cellular communication relates to activated cell-derived sealed membrane vesicles called extracellular vesicles (EVs). The concentrations and contents of EVs in biological fluids depend upon their cells of origin and the stimuli which trigger their production. Research on EVs in preeclampsia has focused on EVs derived from the maternal vasculature (endothelium, vascular smooth muscle) and blood (erythrocytes, leukocytes, and platelets), as well as placental syncytiotrophoblasts. Changes in the concentrations and contents of these EVs may contribute to the pathophysiology of preeclampsia by accentuating the pro-inflammatory and pro-coagulatory states of pregnancy. This review focuses on possible interactions among placental- and maternal-derived EVs and their contents in the initiation and progression of the pathogenesis of preeclampsia. Understanding the contributions of EVs in the pathogenesis of preeclampsia may facilitate their use as diagnostic and prognostic biomarkers.

  12. Extracellular Vesicles in Cardiovascular Theranostics

    OpenAIRE

    Bei, Yihua; Das, Saumya; Rodosthenous, Rodosthenis S.; Holvoet, Paul; Vanhaverbeke, Maarten; Monteiro,Marta Chagas; Monteiro, Valter Vinicius Silva; Radosinska, Jana; Bartekova, Monika; Jansen, Felix; Li, Qian; Rajasingh, Johnson; Xiao, Junjie

    2017-01-01

    Extracellular vesicles (EVs) are small bilayer lipid membrane vesicles that can be released by most cell types and detected in most body fluids. EVs exert key functions for intercellular communication via transferring their bioactive cargos to recipient cells or activating signaling pathways in target cells. Increasing evidence has shown the important regulatory effects of EVs in cardiovascular diseases (CVDs). EVs secreted by cardiomyocytes, endothelial cells, fibroblasts, and stem cells pla...

  13. Immunotherapeutic Potential of Extracellular Vesicles

    OpenAIRE

    Zhang, Bin; Yin, Yijun; Lai, Ruenn Chai; Lim, Sai Kiang

    2014-01-01

    Extracellular vesicle or EV is a term that encompasses all classes of secreted lipid membrane vesicles. Despite being scientific novelties, EVs are gaining importance as a mediator of important physiological and pathological intercellular activities possibly through the transfer of their cargo of protein and RNA between cells. In particular, exosomes, the currently best characterized EVs have been notable for their in vitro and in vivo immunomodulatory activities. Exosomes are nanometer-sized...

  14. Sodium Test

    Science.gov (United States)

    ... low levels of cortisol, aldosterone and sex hormones ( Addison disease ) Drinking too much water as might occur during ... urinary sodium levels may indicate diuretic use or Addison disease. Sodium levels are often evaluated in relation to ...

  15. RNA in extracellular vesicles.

    Science.gov (United States)

    Kim, Kyoung Mi; Abdelmohsen, Kotb; Mustapic, Maja; Kapogiannis, Dimitrios; Gorospe, Myriam

    2017-07-01

    Cells release a range of membrane-enclosed extracellular vesicles (EVs) into the environment. Among them, exosomes and microvesicles (collectively measuring 40-1000 nm in diameter) carry proteins, signaling lipids, and nucleic acids from donor cells to recipient cells, and thus have been proposed to serve as intercellular mediators of communication. EVs transport cellular materials in many physiologic processes, including differentiation, stem cell homeostasis, immune responses, and neuronal signaling. EVs are also increasingly recognized as having a direct role in pathologies such as cancer and neurodegeneration. Accordingly, EVs have been the focus of intense investigation as biomarkers of disease, prognostic indicators, and even therapeutic tools. Here, we review the classes of RNAs present in EVs, both coding RNAs (messenger RNAs) and noncoding RNAs (long noncoding RNAs, microRNAs, and circular RNAs). The rising attention to EV-resident RNAs as biomarkers stems from the fact that RNAs can be detected at extremely low quantities using a number of methods. To illustrate the interest in EV biology, we discuss EV RNAs in cancer and neurodegeneration, two major age-associated disease processes. WIREs RNA 2017, 8:e1413. doi: 10.1002/wrna.1413 For further resources related to this article, please visit the WIREs website. Published 2017. This article is a U.S. Government work and is in the public domain in the USA.

  16. Extracellular Vesicles in Renal Pathophysiology.

    Science.gov (United States)

    Pomatto, Margherita A C; Gai, Chiara; Bussolati, Benedetta; Camussi, Giovanni

    2017-01-01

    Extracellular vesicles are a heterogeneous population of microparticles released by virtually all living cells which have been recently widely investigated in different biological fields. They are typically composed of two primary types (exosomes and microvesicles) and are recently commanding increasing attention as mediators of cellular signaling. Indeed, these vesicles can affect recipient cells by carrying and delivering complex cargos of biomolecules (including proteins, lipids and nucleic acids), protected from enzymatic degradation in the environment. Their importance has been demonstrated in the pathophysiology of several organs, in particular in kidney, where different cell types secrete extracellular vesicles that mediate their communication with downstream urinary tract cells. Over the past few years, evidence has been shown that vesicles participate in kidney development and normal physiology. Moreover, EVs are widely demonstrated to be implicated in cellular signaling during renal regenerative and pathological processes. Although many EV mechanisms are still poorly understood, in particular in kidney, the discovery of their role could help to shed light on renal biological processes which are so far elusive. Lastly, extracellular vesicles secreted by renal cells gather in urine, thus becoming a great resource for disease or recovery markers and a promising non-invasive diagnostic instrument for renal disease. In the present review, we discuss the most recent findings on the role of extracellular vesicles in renal physiopathology and their potential implication in diagnosis and therapy.

  17. Extracellular vesicles in renal disease.

    Science.gov (United States)

    Karpman, Diana; Ståhl, Anne-Lie; Arvidsson, Ida

    2017-09-01

    Extracellular vesicles, such as exosomes and microvesicles, are host cell-derived packages of information that allow cell-cell communication and enable cells to rid themselves of unwanted substances. The release and uptake of extracellular vesicles has important physiological functions and may also contribute to the development and propagation of inflammatory, vascular, malignant, infectious and neurodegenerative diseases. This Review describes the different types of extracellular vesicles, how they are detected and the mechanisms by which they communicate with cells and transfer information. We also describe their physiological functions in cellular interactions, such as in thrombosis, immune modulation, cell proliferation, tissue regeneration and matrix modulation, with an emphasis on renal processes. We discuss how the detection of extracellular vesicles could be utilized as biomarkers of renal disease and how they might contribute to disease processes in the kidney, such as in acute kidney injury, chronic kidney disease, renal transplantation, thrombotic microangiopathies, vasculitides, IgA nephropathy, nephrotic syndrome, urinary tract infection, cystic kidney disease and tubulopathies. Finally, we consider how the release or uptake of extracellular vesicles can be blocked, as well as the associated benefits and risks, and how extracellular vesicles might be used to treat renal diseases by delivering therapeutics to specific cells.

  18. Characteristics of glutamine transport in dog jejunal brush-border membrane vesicles.

    Science.gov (United States)

    Bulus, N M; Abumrad, N N; Ghishan, F K

    1989-07-01

    The present study characterizes glutamine transport across brush-border membrane vesicles (BBMV) prepared from dog jejunum. The purity of these vesicles was demonstrated by a 20-fold enrichment of leucine aminopeptidase, a marker for BBM. Glutamine uptake was found to occur into an osmotically active space with no membrane binding and to exhibit temperature and pH dependence (optimal uptake at pH 7-7.5). Glutamine uptake was driven by an inwardly directed Na+ gradient with a distinct overshoot not observed under K+ gradient. Lithium could not substitute for Na+ as a stimulator of glutamine uptake. Na+-dependent glutamine uptake was not inhibited by methylaminoisobutyric acid, a typical substrate for system A, and was found to be electrogenic and saturable with a Km of 0.97 +/- 0.58 mM and a Vmax of 3.93 +/- 0.99 nmol.mg protein-1.10 s-1. A Na+-glutamine coupling ratio of 1:1 could be demonstrated by a plot of Hill transformation. Na+-independent glutamine uptake was found to be electroneutral and saturable with a Km of 3.70 +/- 0.66 mM and a Vmax of 2.70 +/- 1.55 nmol.mg protein-1.10 s-1. Inhibition studies confirmed the presence of a Na+-dependent as well as a Na+-independent carrier for glutamine uptake. We conclude that glutamine uptake across dog BBMV occurs via two transport systems: a Na+-dependent high-affinity system similar to the neutral brush-border system and a Na+-independent lower-affinity system similar to system L.

  19. Amino acids and carbohydrates absorption by Na+-dependent transporters in the pyloric ceca of Hoplias malabaricus (Erythrinidae

    Directory of Open Access Journals (Sweden)

    Vieira Vania Lucia Pimentel

    2001-01-01

    Full Text Available Information about amino acids and carbohydrate absorption in fish is important to formulate an adequate diet to obtain optimal growth. Therefore, the objective of this study was to investigate if Na+-dependent transporters are involved on the absorption of glycine, L-glutamine, L-leucine, L-lysine, L-proline, L-alanine, and the carbohydrates fructose and glucose in the pyloric ceca of Hoplias malabaricus. The pyloric ceca were mounted in a system of continuous perfusion "in vitro". Amino acids and carbohydrates were placed on the mucosal side at concentrations of 10, 20, and 40mM. The serosal side of the pyloric ceca was positive in relation to the mucosal side. The addition of glycine, L-glutamine, L-leucine, L-lysine, L-proline (all tested concentrations, and glucose (at concentrations of 20 and 40mM increased the positivity of the serosal side, indicating the presence of Na+-dependent transporters in the absorption of these substances. L-alanine and fructose did not change the positivity of the serosal side. The pyloric ceca seem to be the main site of nutrient absorption in the digestive tract of H. malabaricus.

  20. Extracellular Vesicles in Lung Disease.

    Science.gov (United States)

    Kubo, Hiroshi

    2018-01-01

    Accumulating evidence suggests that extracellular vesicles (EVs) play a role in the pathogenesis of lung diseases. These vesicles include exosomes, ectosomes (ie, microparticles, extracellular vesicles, microvesicles, and shedding vesicles), and apoptotic bodies. Exosomes are generated by inward budding of the membrane (endocytosis), subsequent forming of multivesicular bodies, and release by exocytosis. Ectosomes are formed by outward blebbing from the plasma membrane and are then released by proteolytic cleavage from the cell surface. Apoptotic bodies are generated on apoptotic cell shrinkage and death. Extracellular vesicles are released when the cells are activated or undergo apoptosis under inflammatory conditions. The number and types of released EVs are different according to the pathophysiological status of the disease. Therefore, EVs can be novel biomarkers for various lung diseases. EVs contain several molecules, including proteins, mRNA, microRNA, and DNA; they transfer these molecules to distant recipient cells. Circulating EVs modify the targeted cells and influence the microenvironment of the lungs. For this unique capability, EVs are expected to be a new drug delivery system and a novel therapeutic target. Copyright © 2017 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.

  1. Transition metal ion FRET uncovers K(+) regulation of a neurotransmitter/sodium symporter

    DEFF Research Database (Denmark)

    Billesbølle, Christian B; Mortensen, Jonas S; Sohail, Azmat

    2016-01-01

    Neurotransmitter/sodium symporters (NSSs) are responsible for Na(+)-dependent reuptake of neurotransmitters and represent key targets for antidepressants and psychostimulants. LeuT, a prokaryotic NSS protein, constitutes a primary structural model for these transporters. Here we show that K...

  2. Cystadenoma of the seminal vesicle

    Directory of Open Access Journals (Sweden)

    Gil Antônio O.

    2003-01-01

    Full Text Available Primary tumors of the seminal vesicle are extremely rare. Among them, there is a spectrum of tumors derived from both epithelium and stroma and so classified as epithelial-stromal tumors. Herein, we report a case of a cystadenoma in a 49-year-old asymptomatic man, detected in a routine ultrasonography for liver disease follow-up. The digital rectal examination detected a large mass anterior to rectum and posterior to bladder. Computed tomography scan and magnetic resonance imaging showed a normal prostate and a 9.0 cm cystic tumor, replacing the left seminal vesicle. The gross appearance and microscopic aspect was compatible with cystadenoma of seminal vesicle. Patient's postoperative recovery was uneventful. He is currently alive, 3 years after the diagnosis, with no signs of recurrence.

  3. When to biopsy seminal vesicles.

    Science.gov (United States)

    Panach-Navarrete, J; García-Morata, F; Hernández-Medina, J A; Martínez-Jabaloyas, J M

    2015-05-01

    The involvement of seminal vesicles in prostate cancer can affect the prognosis and determine the treatment. The objective of this study was to determine whether we could predict its infiltration at the time of the prostate biopsy to know when to indicate the biopsy of the seminal vesicles. observational retrospective study of 466 patients who underwent seminal vesicle biopsy. The indication for this biopsy was a prostate-specific antigen (PSA) level greater than 10 ng/ml or an asymmetric or obliterated prostatoseminal angle. The following variables were included in the analysis: PSA level, PSA density, prostate volume, number of cores biopsied, suspicious rectal examination, and preservation of the prostatoseminal angle, studying its relationship with the involvement of the seminal vesicles. Forty-one patients (8.8%) had infiltrated seminal vesicles and 425 (91.2%) had no involvement. In the univariate analysis, the cases with infiltration had a higher mean PSA level (P 19.60 ng/dL (P < .01) and 2.95 times higher if there is a suspicious rectal examination (P = .014). Furthermore, this probability increases by 1.04 times for each unit of prostate volume lower (P < .01). The ROC curves showed maximum sensitivity and specificity at 19.6 ng/mL for PSA and 0.39 for PSA density. In this series, greater involvement of seminal vesicles was associated with a PSA level ≥20 ng/ml, a suspicious rectal examination and a lack of prostatoseminal angle preservation. Copyright © 2014 AEU. Publicado por Elsevier España, S.L.U. All rights reserved.

  4. SMALL VESICLES, BIG VEHICLES: EXOSOMES.

    Directory of Open Access Journals (Sweden)

    Saiz-Lopez P

    2016-09-01

    Full Text Available Exosomes are small membranous vesicles released by different cell types. Since their discovery, they have evolved from being considered simple vehicles for the liberation of cellular wastes, to become one of the most promising fields in the area of biomedical research, and more specifically in oncology, since the different malignant tumors release exosomes to all biological fluids, being involved in various functions of the neoplastic process. At present, it is possible to study these vesicles by minimally invasive techniques in patients, which approach us to obtain a more detailed diagnosis and prognosis, as well as to the discovery of new antitumoral therapies

  5. Vesicles and vesicle fusion: coarse-grained simulations

    DEFF Research Database (Denmark)

    Shillcock, Julian C.

    2010-01-01

    Biological cells are highly dynamic, and continually move material around their own volume and between their interior and exterior. Much of this transport encapsulates the material inside phospholipid vesicles that shuttle to and fro, fusing with, and budding from, other membranes. A feature of v...

  6. Sodium and Food Sources

    Science.gov (United States)

    ... Sources Top 10 Sources of Sodium How to Reduce Sodium Sodium Reduction Resources for Everyone Sodium Reduction Fact ... in processed food [PDF-867K] and how to reduce sodium. Sodium Reduction Is Challenging Types of food matter: ...

  7. Hidden Sodium

    Centers for Disease Control (CDC) Podcasts

    2013-03-04

    In this podcast, learn about reducing sodium intake by knowing what to eat and the main sources of sodium in the diet. It's important for a healthy lifestyle.  Created: 3/4/2013 by National Center for Chronic Disease Prevention and Health Promotion (NCCDPHP).   Date Released: 3/4/2013.

  8. Ca2+ Dependence of Synaptic Vesicle Endocytosis.

    Science.gov (United States)

    Leitz, Jeremy; Kavalali, Ege T

    2016-10-01

    Ca(2+)-dependent synaptic vesicle recycling is essential for structural homeostasis of synapses and maintenance of neurotransmission. Although, the executive role of intrasynaptic Ca(2+) transients in synaptic vesicle exocytosis is well established, identifying the exact role of Ca(2+) in endocytosis has been difficult. In some studies, Ca(2+) has been suggested as an essential trigger required to initiate synaptic vesicle retrieval, whereas others manipulating synaptic Ca(2+) concentrations reported a modulatory role for Ca(2+) leading to inhibition or acceleration of endocytosis. Molecular studies of synaptic vesicle endocytosis, on the other hand, have consistently focused on the roles of Ca(2+)-calmodulin dependent phosphatase calcineurin and synaptic vesicle protein synaptotagmin as potential Ca(2+) sensors for endocytosis. Most studies probing the role of Ca(2+) in endocytosis have relied on measurements of synaptic vesicle retrieval after strong stimulation. Strong stimulation paradigms elicit fusion and retrieval of multiple synaptic vesicles and therefore can be affected by several factors besides the kinetics and duration of Ca(2+) signals that include the number of exocytosed vesicles and accumulation of released neurotransmitters thus altering fusion and retrieval processes indirectly via retrograde signaling. Studies monitoring single synaptic vesicle endocytosis may help resolve this conundrum as in these settings the impact of Ca(2+) on synaptic fusion probability can be uncoupled from its putative role on synaptic vesicle retrieval. Future experiments using these single vesicle approaches will help dissect the specific role(s) of Ca(2+) and its sensors in synaptic vesicle endocytosis. © The Author(s) 2015.

  9. Extracellular vesicles in physiological and pathological conditions

    NARCIS (Netherlands)

    Yuana, Yuana; Sturk, Auguste; Nieuwland, Rienk

    2013-01-01

    Body fluids contain surprising numbers of cell-derived vesicles which are now thought to contribute to both physiology and pathology. Tools to improve the detection of vesicles are being developed and clinical applications using vesicles for diagnosis, prognosis, and therapy are under investigation.

  10. Membrane Trafficking and Vesicle Fusion

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 19; Issue 5. Membrane Trafficking and Vesicle Fusion: Post-Palade Era Researchers Win the Nobel Prize. Riddhi Atul Jani Subba Rao Gangi Setty. General Article Volume 19 Issue 5 May 2014 pp 421-445 ...

  11. Dietary sodium

    DEFF Research Database (Denmark)

    Graudal, Niels

    2015-01-01

    The 2013 Institute of Medicine (IOM) report "Sodium Intake in Populations: Assessment of Evidence" did not support the current recommendations of the IOM and the American Heart Association (AHA) to reduce daily dietary sodium intake to below 2,300 mg. The report concluded that the population......-based health outcome evidence was not sufficient to define a safe upper intake level for sodium. Recent studies have extended this conclusion to show that a sodium intake below 2,300 mg/day is associated with increased mortality. In spite of this increasing body of evidence, the AHA, Centers for Disease...... Control (CDC), other public health advisory bodies, and major medical journals have continued to support the current policy of reducing dietary sodium....

  12. Enantioselectivity of vesicle-forming chiral surfactants in capillary electrophoresis. Role of the surfactant headgroup structure.

    Science.gov (United States)

    Mohanty, Ashok; Dey, Joykrishna

    2006-09-22

    Two vesicle-forming single-tailed amino acid derivatized surfactants sodium N-[4-n-dodecyloxybenzoyl]-L-leucinate (SDLL) and sodium N-[4-n-dodecyloxybenzoyl]-L-isoleucinate (SDLIL) have been synthesized and used as pseudo-stationary phase in micellar electrokinetic chromatography to evaluate the role of steric factor of amino acid headgroup and hydrophobic/hydrophilic interactions for enantiomeric separations. The aggregation behavior of the surfactants has been studied in aqueous buffered solution using surface tension and fluorescence probe techniques. Results of these studies have suggested formation of vesicles in aqueous solutions. Microenvironment of the vesicle, which determines the depth of penetration of the analytes into vesicle was determined by fluorescence probe technique using pyrene, N-phenyl-1-naphthylamine (NPN), and 1,6-diphenyl-1,3,5-hexatriene (DPH) as probe molecules. Atropisomeric compounds (+/-)-1,1'-bi-2-naphthol (BOH), (+/-)-1,1'-binaphthyl-2,2'-diamine (BDA), (+/-)-1,1'-binaphthyl-2,2'-diylhydrogen phosphate (BNP) and Tröger's base (TB) and chiral compound benzoin (BZN) has been enantioseparated. The separations were optimized with respect to surfactant concentration, pH, and borate buffer concentration. SDLL was found to provide better resolution for BOH, BNP, and BZN. On the other hand, SDLIL offers better resolution for BDA. The chromatographic results have been discussed in the light of the aggregation behavior of the surfactants and the interaction of the solutes with the vesicles.

  13. Vesicle fission of giant unilamellar vesicles of liquid-ordered-phase membranes induced by amphiphiles with a single long hydrocarbon chain.

    Science.gov (United States)

    Inaoka, Yasuyuki; Yamazaki, Masahito

    2007-01-16

    Vesicle fissions are very important processes of biomembranes in cells, but their mechanisms are not clear and are controversial. Using the single giant unilamellar vesicle (GUV) method, we recently found that low concentrations (less than the critical micelle concentration (CMC)) of lysophosphatidylcholine (lyso-PC) induced the vesicle fission of GUVs of dipalmitoylphosphatidylcholine/cholesterol(6/4) (DPPC/chol(6/4)) membranes and sphingomyelin/cholesterol membranes (6/4) in the liquid-ordered (lo) phase. In this report, to elucidate its mechanism, we have investigated the effect of low concentrations (much less than their CMC) of other amphiphiles with a single long hydrocarbon chain (i.e., single long chain amphiphiles) on DPPC/chol(6/4) GUVs as well as the effect of the membrane composition on the lyso-PC-induced vesicle fission. We found that low concentrations of single long chain amphiphiles (lyosophosphatidic acid, octylglucoside, and sodium dodecyl sulfate) induced the shape change from a prolate to two spheres connected by a very narrow neck, indicating that the single long chain amphiphiles can be partitioned into the external monolayer in the lo phase of the GUV from the aqueous solution. As the single long chain amphiphile concentrations were increased, all of them induced vesicle fission of DPPC/chol(6/4) GUVs above their threshold concentrations. To elucidate the role of cholesterol in the single long chain amphiphile-induced vesicle fission, we investigated the effect of lyso-PC on GUVs of dioleoyl-PC (DOPC)/chol(6/4) membranes in the Lalpha phase; no vesicle fission occurred, indicating that cholesterol in itself did not play an important role in the vesicle fission. Finally, to elucidate the effect of the inclusion of DOPC in the lo-phase membrane of GUVs on the lyso-PC-induced vesicle fission of the DPPC/chol(6/4) GUV, we investigated the effect of low concentrations of lyso-PC on GUVs of DPPC/DOPC/chol membranes. With an increase in DOPC

  14. The readily releasable pool of synaptic vesicles.

    Science.gov (United States)

    Kaeser, Pascal S; Regehr, Wade G

    2017-04-01

    Each presynaptic bouton is densely packed with many vesicles, only a small fraction of which are available for immediate release. These vesicles constitute the readily releasable pool (RRP). The RRP size, and the probability of release of each vesicle within the RRP, together determine synaptic strength. Here, we discuss complications and recent advances in determining the size of the physiologically relevant RRP. We consider molecular mechanisms to generate and regulate the RRP, and discuss the relationship between vesicle docking and the RRP. We conclude that many RRP vesicles are docked, that some docked vesicles may not be part of the RRP, and that undocked vesicles can contribute to the RRP by rapid recruitment to unoccupied, molecularly activated ready-to-release sites. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Phospholipid Vesicles in Materials Science

    Energy Technology Data Exchange (ETDEWEB)

    Granick, Steve [Univ. of Illinois, Champaign, IL (United States)

    2016-05-11

    The objective of this research was to develop the science basis needed to deploy phospholipid vesicles as functional materials in energy contexts. Specifically, we sought to: (1) Develop an integrated molecular-level understanding of what determines their dynamical shape, spatial organization, and responsiveness to complex, time-varying environments; and (2) Develop understanding of their active transportation in crowded environments, which our preliminary measurements in cells suggest may hold design principles for targeting improved energy efficiency in new materials systems. The methods to do this largely involved fluorescence imaging and other spectroscopy involving single particles, vesicles, particles, DNA, and endosomes. An unexpected importance outcome was a new method to image light-emitting diodes during actual operation using super-resolution spectroscopy.

  16. Dynamics of endocytic vesicle creation.

    Science.gov (United States)

    Perrais, David; Merrifield, Christien J

    2005-11-01

    Clathrin-mediated endocytosis is the main path for receptor internalization in metazoans and is essential for controlling cell integrity and signaling. It is driven by a large array of protein and lipid interactions that have been deciphered mainly by biochemical and genetic means. To place these interactions into context, and ultimately build a fully operative model of endocytosis at the molecular level, it is necessary to know the kinetic details of the role of each protein in this process. In this review, we describe the recent efforts made, by using live cell imaging, to define clear steps in the formation of endocytic vesicles and to observe the recruitment of key proteins during membrane invagination, the scission of a newly formed vesicle, and its movement away from the plasma membrane.

  17. Extracellular vesicles and blood diseases.

    Science.gov (United States)

    Nomura, Shosaku

    2017-04-01

    Extracellular vesicles (EVs) are small membrane vesicles released from many different cell types by the exocytic budding of the plasma membrane in response to cellular activation or apoptosis. EVs disseminate various bioactive effectors originating from the parent cells and transfer functional RNA and protein between cells, enabling them to alter vascular function and induce biological responses involved in vascular homeostasis. Although most EVs in human blood originate from platelets, EVs are also released from leukocytes, erythrocytes, endothelial cells, smooth muscle cells, and cancer cells. EVs were initially thought to be small particles with procoagulant activity; however, they can also evoke cellular responses in the immediate microenvironments and transport microRNAs (miRNA) into target cells. In this review, we summarize the recent literature relevant to EVs, including a growing list of clinical disorders that are associated with elevated EV levels. These studies suggest that EVs play roles in various blood diseases.

  18. Immunotherapeutic potential of extracellular vesicles

    Directory of Open Access Journals (Sweden)

    Bin eZhang

    2014-10-01

    Full Text Available Extracellular vesicles or EVs is a term that encompasses all classes of secreted lipid membrane vesicles. Despite being scientific novelties, EVs are gaining importance as a mediator of important physiological and pathological intercellular activities possibly through the transfer of their cargo of protein and RNA between cells. In particular, exosomes the currently best characterized EVs have been notable for their in vitro and in vivo immunomodulatory activities. Exosomes are nanometer-sized endosome-derived vesicles secreted by many cell types and their immunomodulatory potential is independent of their cell source. Besides immune cells such as dendritic cells, macrophages and T cells, cancer and stem cells also secrete immunologically active exosomes that could influence both physiological and pathological processes. The immunological activities of exosomes affect both innate and adaptive immunity and include antigen presentation, T cell activation, T cell polarisation to Tregs, immune suppression and anti-inflammation. As such, exosomes carry much immunotherapeutic potential as a therapeutic agent and a therapeutic target.

  19. Synaptic vesicle proteins and active zone plasticity

    Directory of Open Access Journals (Sweden)

    Robert J Kittel

    2016-04-01

    Full Text Available Neurotransmitter is released from synaptic vesicles at the highly specialized presynaptic active zone. The complex molecular architecture of active zones mediates the speed, precision and plasticity of synaptic transmission. Importantly, structural and functional properties of active zones vary significantly, even for a given connection. Thus, there appear to be distinct active zone states, which fundamentally influence neuronal communication by controlling the positioning and release of synaptic vesicles. Vice versa, recent evidence has revealed that synaptic vesicle components also modulate organizational states of the active zone.The protein-rich cytomatrix at the active zone (CAZ provides a structural platform for molecular interactions guiding vesicle exocytosis. Studies in Drosophila have now demonstrated that the vesicle proteins Synaptotagmin-1 (Syt1 and Rab3 also regulate glutamate release by shaping differentiation of the CAZ ultrastructure. We review these unexpected findings and discuss mechanistic interpretations of the reciprocal relationship between synaptic vesicles and active zone states, which has heretofore received little attention.

  20. Single-vesicle imaging reveals different transport mechanisms between glutamatergic and GABAergic vesicles

    NARCIS (Netherlands)

    Farsi, Z.; Preobraschenski, J.; Bogaart, G. van den; Riedel, D.; Jahn, R.; Woehler, A.

    2016-01-01

    Synaptic transmission is mediated by the release of neurotransmitters, which involves exo-endocytotic cycling of synaptic vesicles. To maintain synaptic function, synaptic vesicles are refilled with thousands of neurotransmitter molecules within seconds after endocytosis, using the energy provided

  1. Vesicle-cholesterol interactions : Effects of added cholesterol on gel-to-liquid crystal transitions in a phospholipid membrane and five dialkyl-based vesicles as monitored using DSC

    NARCIS (Netherlands)

    Blandamer, Michael J.; Briggs, B; Cullis, PM; Rawlings, BJ; Engberts, Jan B. F. N.; Cullis, Paul M.; Rawlings, Bernard J.

    2003-01-01

    Differential scanning calorimetry (DSC) results are reported characterising the effects of added cholesterol (CHOL) on vesicle bilayer systems formed in aqueous systems by three sodium dialkylphosphates, (RO)(2)PO2--Na+ where R = dodecyl (DDP), tetradecyl (DTP) and octadecyl (DOP), (ii) two

  2. Extracellular Vesicles: Evolving Contributors in Autoimmunity

    OpenAIRE

    Katsiougiannis, Stergios

    2015-01-01

    Extracellular vesicles, including microvesicles, exosomes and apoptotic bodies are recognized as carriers of pathogen-associated molecules with direct involvement in immune signaling and inflammation. Those observations have enforced the way these membranous vesicles are being considered as promising immunotherapeutic targets. In this review, we discuss the emerging roles of extracellular vesicles in autoimmunity and highlights their potential use as disease biomarkers as well as targets for ...

  3. Exosomes: secreted vesicles and intercellular communications

    OpenAIRE

    Théry, Clotilde

    2011-01-01

    Exosomes are small membrane vesicles of endocytic origin secreted by most cell types, and are thought to play important roles in intercellular communications. Although exosomes were originally described in 1983, interest in these vesicles has really increased dramatically in the last 3 years, after the finding that they contain mRNA and microRNA. This discovery sparked renewed interest for the general field of membrane vesicles involved in intercellular communications, and research on these s...

  4. Sodium technology

    Energy Technology Data Exchange (ETDEWEB)

    Kurzeka, W.J.; Oliva, R.M.; Horton, P.

    1973-12-01

    The objective of this program is to conduct friction screening tests in an environment of high-temperature, high-purity liquid sodium or sodium vapor to: (1) develop backup materials, processes, and vendors for core component wear pads, (2) investigate material treatments and coatings for improvement of wear behavior of common LMFBR structural materials, (3) evaluate weld-deposited hardfacings and/or prefabricated bearing materials for use in long-term, high-temperature, high-fluence regions, (4) evaluate bearing materials with a low potential for change in surface composition due to corrosion or mass transfer effects, and (5) develop statistical confidence in friction values for selected material combinations.

  5. Trafficking of astrocytic vesicles in hippocampal slices

    Energy Technology Data Exchange (ETDEWEB)

    Potokar, Maja; Kreft, Marko [Laboratory of Neuroendocrinology-Molecular Cell Physiology, Institute of Pathophysiology, Faculty of Medicine, University of Ljubljana, Zaloska 4, 1000 Ljubljana (Slovenia); Celica Biomedical Center, Technology Park 24, 1000 Ljubljana (Slovenia); Lee, So-Young; Takano, Hajime; Haydon, Philip G. [Department of Neuroscience, Room 215, Stemmler Hall, University of Pennsylvania, School of Medicine, Philadelphia, PA 19104 (United States); Zorec, Robert, E-mail: Robert.Zorec@mf.uni-lj.si [Laboratory of Neuroendocrinology-Molecular Cell Physiology, Institute of Pathophysiology, Faculty of Medicine, University of Ljubljana, Zaloska 4, 1000 Ljubljana (Slovenia); Celica Biomedical Center, Technology Park 24, 1000 Ljubljana (Slovenia)

    2009-12-25

    The increasingly appreciated role of astrocytes in neurophysiology dictates a thorough understanding of the mechanisms underlying the communication between astrocytes and neurons. In particular, the uptake and release of signaling substances into/from astrocytes is considered as crucial. The release of different gliotransmitters involves regulated exocytosis, consisting of the fusion between the vesicle and the plasma membranes. After fusion with the plasma membrane vesicles may be retrieved into the cytoplasm and may continue to recycle. To study the mobility implicated in the retrieval of secretory vesicles, these structures have been previously efficiently and specifically labeled in cultured astrocytes, by exposing live cells to primary and secondary antibodies. Since the vesicle labeling and the vesicle mobility properties may be an artifact of cell culture conditions, we here asked whether the retrieving exocytotic vesicles can be labeled in brain tissue slices and whether their mobility differs to that observed in cell cultures. We labeled astrocytic vesicles and recorded their mobility with two-photon microscopy in hippocampal slices from transgenic mice with fluorescently tagged astrocytes (GFP mice) and in wild-type mice with astrocytes labeled by Fluo4 fluorescence indicator. Glutamatergic vesicles and peptidergic granules were labeled by the anti-vesicular glutamate transporter 1 (vGlut1) and anti-atrial natriuretic peptide (ANP) antibodies, respectively. We report that the vesicle mobility parameters (velocity, maximal displacement and track length) recorded in astrocytes from tissue slices are similar to those reported previously in cultured astrocytes.

  6. Reversibly formed bilayer vesicles: Energetics and polydispersity

    DEFF Research Database (Denmark)

    Bergstöm, M.

    1997-01-01

    orders of magnitude larger than where the local free energy minima of the equilibrium vesicle actually occur. Moreover, according to our analysis, the relative width of a vesicle size distribution, sigma(R)/R-max, is generally at full equilibrium equal to 0.283, independently of the energetic vesicle....... and a statistical-mechanical factor that accounts for the fluctuations in composition, chain packing density and shape. We demonstrate that the free energy required to form a spherical vesicle is made up of two main contributions: the (size-independent) work of bending the constituent monolayers and the work...

  7. Extracellular vesicles in cardiovascular homeostasis and disease.

    Science.gov (United States)

    Hutcheson, Joshua D; Aikawa, Elena

    2018-02-19

    Extracellular vesicles have emerged as one of the most important means through which cells interact with each other and the extracellular environment, but extracellular vesicle research remains challenging due to their small size, limited amount of material required for traditional molecular biology assays and inconsistency in the methods of their isolation. The advent of new technologies and standards in the field, however, have led to increased mechanistic insight into extracellular vesicle function. Herein, the latest studies on the role of extracellular vesicles in cardiovascular physiology and disease are discussed. Extracellular vesicles help control cardiovascular homeostasis and remodelling by mediating communication between cells and directing alterations in the extracellular matrix to respond to changes in the environment. The message carried from the parent cell to extracellular space can be intended for both local (within the same tissue) and distal (downstream of blood flow) targets. Pathological cargo loaded within extracellular vesicles could further result in various diseases. On the contrary, new studies indicate that injection of extracellular vesicles obtained from cultured cells into diseased tissues can promote restoration of normal tissue function. Extracellular vesicles are an integral part of cell and tissue function, and harnessing the properties inherent to extracellular vesicles may provide a therapeutic strategy to promote tissue regeneration.

  8. Extracellular vesicles in cartilage homeostasis and osteoarthritis.

    Science.gov (United States)

    Miyaki, Shigeru; Lotz, Martin K

    2018-01-01

    Extracellular vesicles carry bioactive molecules that can be transferred between cells and tissues. The purpose of this review is to describe how extracellular vesicles regulate functions of cells in cartilage and other joint tissues. The potential application of extracellular vesicles in the treatment of osteoarthritis and as biomarkers will also be discussed. Extracellular vesicles are found in synovial fluid, in articular cartilage and in the supernatants of synoviocytes and chondrocytes. Extracellular vesicles in cartilage have been proposed to be involved in cross talk between cells in joint tissues and to affect extracellular matrix turnover and inflammation. Extracellular vesicles from arthritic joints can promote abnormal gene expression and changes in cartilage extracellular matrix, including abnormal mineralization. Promising results were obtained in the therapeutic application of mesenchymal stem cell-derived extracellular vesicles for cartilage repair and experimental osteoarthritis. Extracellular vesicles have emerged as vehicles for the exchange of bioactive signaling molecules within cartilage and between joint tissues to promote joint homeostasis and arthritis pathogenesis. As the molecular content of extracellular vesicles can be customized, they offer utility in therapeutic applications.

  9. How Anionic Vesicles Steer the Oligomerization of Enzymatically Oxidized p-Aminodiphenylamine (PADPA) toward a Polyaniline Emeraldine Salt (PANI-ES)-Type Product.

    Science.gov (United States)

    Luginbühl, Sandra; Bertschi, Louis; Willeke, Martin; Schuler, Lukas D; Walde, Peter

    2016-09-27

    The oxidation of the aniline dimer, p-aminodiphenylamine (PADPA), with Trametes versicolor laccase and O2 in an aqueous solution of pH 3.5 is controlled by negatively charged AOT (sodium bis(2-ethylhexyl) sulfosuccinate) vesicles. With vesicles, a product resembling polyaniline in its emeraldine salt form (PANI-ES) is obtained, in contrast to the reaction without vesicles where no such product is formed. To understand this observation, the product distribution and structures from the reaction with and without vesicles were determined by using partially selectively deuterated PADPA as a starting material and analyzing the products with HPLC-MS. We found that in the presence of vesicles the main product is obtained in about 50% yield, which is the N-C-para-coupled PADPA dimer that has spectroscopic properties of PANI-ES, as determined by time-dependent density functional theory (TD-DFT) calculations. A secondary reaction route leads to longer PADPA oligomers that must contain a phenazine core. Without vesicles, PADPA and its products undergo partial hydrolysis, but in the presence of vesicles, hydrolysis does not occur. Because molecular dynamics (MD) simulations show that the main intermediate oxidation product is embedded within the vesicle membrane, where the water content is very low, we propose that the microenvironment of the vesicle membrane protects the oxidation products from unwanted hydrolysis.

  10. Sodium Oxybate

    Science.gov (United States)

    ... the measuring device from its wrapper. Open the bottle by pushing down on the cap and turning the cap counterclockwise (to the left) ... Rinse the measuring device with water Replace the cap on the bottle of sodium oxybate and return the bottle and ...

  11. Sodium Phosphate

    Science.gov (United States)

    ... potassium in your blood; a high level of sodium or phosphate in your blood; colitis (inflammation of the large intestine) or other conditions that irritate your intestine; slow moving bowels; heart failure (condition in which the heart cannot pump blood through the body as well as it ...

  12. An immunoassay for urinary extracellular vesicles.

    Science.gov (United States)

    Salih, Mahdi; Fenton, Robert A; Knipscheer, Jeroen; Janssen, Joost W; Vredenbregt-van den Berg, Mirella S; Jenster, Guido; Zietse, Robert; Hoorn, Ewout J

    2016-04-15

    Although nanosized urinary extracellular vesicles (uEVs) are increasingly used for biomarker discovery, their isolation currently relies on time-consuming techniques hindering high-throughput application. To navigate this problem, we designed an immunoassay to isolate, quantify, and normalize uEV proteins. The uEV immunoassay consists of a biotinylated CD9 antibody to isolate uEVs, an antibody against the protein of interest, and two conjugated antibodies to quantify the protein of interest and CD9. As a proof of principle, the immunoassay was developed to analyze the water channel aquaporin-2 (AQP2) and the sodium-chloride cotransporter (NCC). CD9 was used as a capture antibody because immunoprecipitation showed that anti-CD9 antibody, but not anti-CD63 antibody, isolated AQP2 and NCC. CD9 correlated strongly with urine creatinine, allowing CD9 to be used for normalization of spot urines. The uEV immunoassay detected AQP2 and NCC with high sensitivity, low coefficients of variance, and stability in dilution series. After water loading in healthy subjects, the uEV immunoassay detected decreases in AQP2 and NCC equally well as the traditional method using ultracentrifugation and immunoblot. The uEV immunoassay also reliably detected lower and higher AQP2 or NCC levels in uEVs from patients with pathological water or salt reabsorption, respectively. In summary, we report a novel approach to analyze uEVs that circumvents existing isolation and normalization issues, requires small volumes of urine, and detects anticipated changes in physiological responses and clinical disorders. Copyright © 2016 the American Physiological Society.

  13. Involvement of multiple sodium ions in intestinal d-glucose transport.

    OpenAIRE

    Kaunitz, J D; Gunther, R.; Wright, E. M.

    1982-01-01

    Brush border membrane vesicles isolated from rabbit small intestine were used to measure the interactions between sodium and glucose transport with a rapid uptake technique. A plot of glucose uptake rate vs. increasing sodium concentration yielded a sigmoid curve. Hill analysis revealed a coefficient of 1.9 +/- 0.02 (+/- SEM), consistent with at least two sodium ions involved in glucose transport. Transport coupling was then measured directly with double-label experiments in which the uptakes...

  14. Self-Assembly of Bilayer Vesicles Made of Saturated Long Chain Fatty Acids.

    Science.gov (United States)

    Douliez, Jean-Paul; Houssou, Bérénice Houinsou; Fameau, A-Laure; Navailles, Laurence; Nallet, Frédéric; Grélard, Axelle; Dufourc, Erick J; Gaillard, Cédric

    2016-01-19

    Saturated long chain fatty acids (sLCFA, e.g., C14:0, C16:0, and C18:0) are potentially the greenest and cheapest surfactants naturally available. However, because aqueous sodium soaps of sLCFA are known to crystallize, the self-assembly of stable bilayer vesicles has not been reported yet. Here, by using such soaps in combination with guanidine hydrochloride (GuHCl), which has been shown recently to prevent crystallization, we were capable of producing stable bilayer vesicles made of sLCFA. The phase diagrams were established for a variety of systems showing that vesicles can form in a broad range of composition and pH. Both solid state NMR and small-angle neutron scattering allowed demonstrating that in such vesicles sLCFA are arranged in a bilayer structure which exhibits similar dynamic and structural properties as those of phospholipid membranes. We expect these vesicles to be of interest as model systems of protocells and minimal cells but also for various applications since fatty acids are potentially substitutes to phospholipids, synthetic surfactants, and polymers.

  15. Polycyclic aromatic hydrocarbons storage by Fusarium solani in intracellular lipid vesicles

    Energy Technology Data Exchange (ETDEWEB)

    Verdin, Anthony [Laboratoire de Mycologie/Phytopathologie/Environnement, Universite du Littoral-Cote d' Opale, 17 avenue Bleriot, BP 699, 62228 Calais Cedex (France); Lounes-Hadj Sahraoui, Anissa [Laboratoire de Mycologie/Phytopathologie/Environnement, Universite du Littoral-Cote d' Opale, 17 avenue Bleriot, BP 699, 62228 Calais Cedex (France)]. E-mail: lounes@univ-littoral.fr; Newsam, Ray [Department of Biosciences, University of Kent, Canterbury CT2 7NJ (United Kingdom); Robinson, Gary [Department of Biosciences, University of Kent, Canterbury CT2 7NJ (United Kingdom); Durand, Roger [Laboratoire de Mycologie/Phytopathologie/Environnement, Universite du Littoral-Cote d' Opale, 17 avenue Bleriot, BP 699, 62228 Calais Cedex (France)

    2005-01-01

    Accumulation and elimination of polycyclic aromatic hydrocarbons (PAHs) were studied in the fungus Fusarium solani. When the fungus was grown on a synthetic medium containing benzo[a]pyrene, hyphae of F. solani contained numerous lipid vesicles which could be stained by the lipid-specific dyes: Sudan III and Rhodamine B. The fluorescence produced by Rhodamine B and PAH benzo[a]pyrene were at the same locations in the fungal hyphae, indicating that F. solani stored PAH in pre-existing lipid vesicles. A passive temperature-independent process is involved in the benzo[a]pyrene uptake and storage. Sodium azide, a cytochrome c oxidation inhibitor, and the two cytoskeleton inhibitors colchicine and cytochalasin did not prevent the transport and accumulation of PAH in lipid vesicles of F. solani hyphae. F. solani degraded a large range of PAHs at different rates. PAH intracellular storage in lipid vesicles was not necessarily accompanied by degradation and was common to numerous other fungi. - Fungi can store PAHs intracellularly in lipid vesicles independently of their PAH degradation abilities.

  16. Extracellular Vesicles in Cardiovascular Theranostics.

    Science.gov (United States)

    Bei, Yihua; Das, Saumya; Rodosthenous, Rodosthenis S; Holvoet, Paul; Vanhaverbeke, Maarten; Monteiro, Marta Chagas; Monteiro, Valter Vinicius Silva; Radosinska, Jana; Bartekova, Monika; Jansen, Felix; Li, Qian; Rajasingh, Johnson; Xiao, Junjie

    2017-01-01

    Extracellular vesicles (EVs) are small bilayer lipid membrane vesicles that can be released by most cell types and detected in most body fluids. EVs exert key functions for intercellular communication via transferring their bioactive cargos to recipient cells or activating signaling pathways in target cells. Increasing evidence has shown the important regulatory effects of EVs in cardiovascular diseases (CVDs). EVs secreted by cardiomyocytes, endothelial cells, fibroblasts, and stem cells play essential roles in pathophysiological processes such as cardiac hypertrophy, cardiomyocyte survival and apoptosis, cardiac fibrosis, and angiogenesis in relation to CVDs. In this review, we will first outline the current knowledge about the physical characteristics, biological contents, and isolation methods of EVs. We will then focus on the functional roles of cardiovascular EVs and their pathophysiological effects in CVDs, as well as summarize the potential of EVs as therapeutic agents and biomarkers for CVDs. Finally, we will discuss the specific application of EVs as a novel drug delivery system and the utility of EVs in the field of regenerative medicine.

  17. Illuminating the physiology of extracellular vesicles

    OpenAIRE

    Choi, Hongyoon; Lee, Dong Soo

    2016-01-01

    Extracellular vesicles play a crucial role in intercellular communication by transmitting biological materials from donor cells to recipient cells. They have pathophysiologic roles in cancer metastasis, neurodegenerative diseases, and inflammation. Extracellular vesicles also show promise as emerging therapeutics, with understanding of their physiology including targeting, distribution, and clearance therefore becoming an important issue. Here, we review recent advances in methods for trackin...

  18. Amyloglucosidase enzymatic reactivity inside lipid vesicles

    Directory of Open Access Journals (Sweden)

    Kim Jin-Woo

    2007-10-01

    Full Text Available Abstract Efficient functioning of enzymes inside liposomes would open new avenues for applications in biocatalysis and bioanalytical tools. In this study, the entrapment of amyloglucosidase (AMG (EC 3.2.1.3 from Aspergillus niger into dipalmitoylphosphatidylcholine (DPPC multilamellar vesicles (MLVs and large unilamellar vesicles (LUVs was investigated. Negative-stain, freeze-fracture, and cryo-transmission electron microscopy images verified vesicle formation in the presence of AMG. Vesicles with entrapped AMG were isolated from the solution by centrifugation, and vesicle lamellarity was identified using fluorescence laser confocal microscopy. The kinetics of starch hydrolysis by AMG was modeled for two different systems, free enzyme in aqueous solution and entrapped enzyme within vesicles in aqueous suspension. For the free enzyme system, intrinsic kinetics were described by a Michaelis-Menten kinetic model with product inhibition. The kinetic constants, Vmax and Km, were determined by initial velocity measurements, and Ki was obtained by fitting the model to experimental data of glucose concentration-time curves. Predicted concentration-time curves using these kinetic constants were in good agreement with experimental measurements. In the case of the vesicles, the time-dependence of product (glucose formation was experimentally determined and simulated by considering the kinetic behavior of the enzyme and the permeation of substrate into the vesicle. Experimental results demonstrated that entrapped enzymes were much more stable than free enyzme. The entrapped enzyme could be recycled with retention of 60% activity after 3 cycles. These methodologies can be useful in evaluating other liposomal catalysis operations.

  19. Extracellular vesicles in coronary artery disease.

    Science.gov (United States)

    Boulanger, Chantal M; Loyer, Xavier; Rautou, Pierre-Emmanuel; Amabile, Nicolas

    2017-05-01

    Membrane vesicles released in the extracellular space are composed of a lipid bilayer enclosing soluble cytosolic material and nuclear components. Extracellular vesicles include apoptotic bodies, exosomes, and microvesicles (also known previously as microparticles). Originating from different subcellular compartments, the role of extracellular vesicles as regulators of transfer of biological information, acting locally and remotely, is now acknowledged. Circulating vesicles released from platelets, erythrocytes, leukocytes, and endothelial cells contain potential valuable biological information for biomarker discovery in primary and secondary prevention of coronary artery disease. Extracellular vesicles also accumulate in human atherosclerotic plaques, where they affect major biological pathways, including inflammation, proliferation, thrombosis, calcification, and vasoactive responses. Extracellular vesicles also recapitulate the beneficial effect of stem cells to treat cardiac consequences of acute myocardial infarction, and now emerge as an attractive alternative to cell therapy, opening new avenues to vectorize biological information to target tissues. Although interest in microvesicles in the cardiovascular field emerged about 2 decades ago, that for extracellular vesicles, in particular exosomes, started to unfold a decade ago, opening new research and therapeutic avenues. This Review summarizes current knowledge on the role of extracellular vesicles in coronary artery disease, and their emerging potential as biomarkers and therapeutic agents.

  20. Detection of extracellular vesicles: size does matter

    NARCIS (Netherlands)

    van der Pol, E.

    2015-01-01

    Cells release small sacks filled with fluid, which are called "extracellular vesicles". The diameter of extracellular vesicles (EV) typically ranges from 30 nm to 1 µm. Because cells release EV into their environment, our body fluids contain numerous EV. Cells release EV to remove waste and to

  1. Synaptic vesicle distribution by conveyor belt.

    Science.gov (United States)

    Moughamian, Armen J; Holzbaur, Erika L F

    2012-03-02

    The equal distribution of synaptic vesicles among synapses along the axon is critical for robust neurotransmission. Wong et al. show that the continuous circulation of synaptic vesicles throughout the axon driven by molecular motors ultimately yields this even distribution. Copyright © 2012 Elsevier Inc. All rights reserved.

  2. Urinary extracellular vesicles: biomarkers and beyond

    NARCIS (Netherlands)

    M. Salih (Mahdi)

    2017-01-01

    markdownabstractExtracellular vesicles have been isolated in various body fluids including urine. The cargo of urinary extracellular vesicles (uEVs) is composed of proteins and nucleic acids reflecting the physiological and possibly the pathophysiological state of cells lining the nephron. Because

  3. Test Your Sodium Smarts

    Science.gov (United States)

    ... You may be surprised to learn how much sodium is in many foods. Sodium, including sodium chloride ... foods with little or no salt. Test your sodium smarts by answering these 10 questions about which ...

  4. Fusion Competent Synaptic Vesicles Persist upon Active Zone Disruption and Loss of Vesicle Docking.

    Science.gov (United States)

    Wang, Shan Shan H; Held, Richard G; Wong, Man Yan; Liu, Changliang; Karakhanyan, Aziz; Kaeser, Pascal S

    2016-08-17

    In a nerve terminal, synaptic vesicle docking and release are restricted to an active zone. The active zone is a protein scaffold that is attached to the presynaptic plasma membrane and opposed to postsynaptic receptors. Here, we generated conditional knockout mice removing the active zone proteins RIM and ELKS, which additionally led to loss of Munc13, Bassoon, Piccolo, and RIM-BP, indicating disassembly of the active zone. We observed a near-complete lack of synaptic vesicle docking and a strong reduction in vesicular release probability and the speed of exocytosis, but total vesicle numbers, SNARE protein levels, and postsynaptic densities remained unaffected. Despite loss of the priming proteins Munc13 and RIM and of docked vesicles, a pool of releasable vesicles remained. Thus, the active zone is necessary for synaptic vesicle docking and to enhance release probability, but releasable vesicles can be localized distant from the presynaptic plasma membrane. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. Alternative methods for characterization of extracellular vesicles

    Directory of Open Access Journals (Sweden)

    Fatemeh eMomen-Heravi

    2012-09-01

    Full Text Available Extracellular vesicles are nano-sized vesicles released by all cells in vitro as well as in vivo. Their role has been implicated mainly in cell-cell communication, but also in disease biomarkers and more recently in gene delivery. They represent a snapshot of the cell status at the moment of release and carry bioreactive macromolecules such as nucleic acids, proteins and lipids. A major limitation in this emerging new field is the availability/awareness of techniques to isolate and properly characterize Extracellular vesicles. The lack of gold standards makes comparing different studies very difficult and may potentially hinder some Extracellular vesicles -specific evidence. Characterization of Extracellular vesicles has also recently seen many advances with the use of Nanoparticle Tracking Analysis (NTA, flow cytometry, cryo-EM instruments and proteomic technologies. In this review, we discuss the latest developments in translational technologies involving characterization methods including the facts in their support and the challenges they face.

  6. Extracellular vesicles: new players in cardiovascular diseases.

    Science.gov (United States)

    Gaceb, Abderahim; Martinez, Maria Carmen; Andriantsitohaina, Ramaroson

    2014-05-01

    Extracellular vesicles, particles released by all cell types, represent a new way to convey information between cells such as proteins, second messengers, and genetic information to modify the phenotype and function of the target cells. Recent data suggest that extracellular vesicles play a crucial role in both physiology and pathology, including coagulation, angiogenesis, cell survival, modulation of the immune response, and inflammation. Thus extracellular vesicles participate in the processes of cardiovascular diseases from atherosclerosis, myocardial infarction to heart failure. Consequently, extracellular vesicles can potentially be exploited for therapy, prognosis, and biomarkers for health and disease. This review focuses on the role of extracellular vesicles in the development of cardiovascular diseases, as well as the deleterious and beneficial effects that they may provide in vascular cells and myocardium. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. [Transvesical Removal of Seminal Vesicle Cystadenoma].

    Science.gov (United States)

    Takayasu, Kenta; Harada, Jiro; Kawa, Gen; Ota, Syuichi; Sakurai, Takanori

    2015-07-01

    Primary tumors of the seminal vesicles are extremely rare. There have been 25 reports of this tumor from overseas and most cases are cystadenoma. We report a case of seminal vesicle cystadenoma in a 70-year-old man who presented with lower abdominal pain and urinary frequency. A digital rectal examination detected a projecting and hard mass in the right side of the prostate. Magnetic resonance imaging (MRI) showed a 15 cm multiple cystic mass continuous with the right seminal vesicle. A transrectal needle biopsy revealed benign tissue. The tumor was resected using an open transvesical approach that enabled full exposure of the seminal vesicle without damaging the nerves and blood supply of the bladder. Pathology was consistent with a benign seminal vesicle cystadenoma. We describe the natural history, pathology,and surgical approach in this case.

  8. Pushing synaptic vesicles over the RIM.

    Science.gov (United States)

    Kaeser, Pascal S

    2011-05-01

    In a presynaptic nerve terminal, neurotransmitter release is largely restricted to specialized sites called active zones. Active zones consist of a complex protein network, and they organize fusion of synaptic vesicles with the presynaptic plasma membrane in response to action potentials. Rab3-interacting molecules (RIMs) are central components of active zones. In a recent series of experiments, we have systematically dissected the molecular mechanisms by which RIMs operate in synaptic vesicle release. We found that RIMs execute two critical functions of active zones by virtue of independent protein domains. They tether presyanptic Ca(2+) channels to the active zone, and they activate priming of synaptic vesicles by monomerizing homodimeric, constitutively inactive Munc13. These data indicate that RIMs orchestrate synaptic vesicle release into a coherent process. In conjunction with previous studies, they suggest that RIMs form a molecular platform on which plasticity of synaptic vesicle release can operate.

  9. Apoptotic Bodies: Selective Detection in Extracellular Vesicles.

    Science.gov (United States)

    Hauser, Paul; Wang, Sha; Didenko, Vladimir V

    2017-01-01

    Normal and dying cells release various types of membrane-bound vesicles including microvesicles, exosomes, and apoptotic bodies. These vesicles play important roles in intercellular communication and signal transduction. However, their diverse forms and subtypes fluctuate in size and other properties. In result current purification approaches do not fully discriminate between different categories of extracellular vesicles. Here, we present a fluorescence technique that specifically identifies apoptotic bodies in preparations of microvesicles, exosomes, and other extracellular vesicles.The approach exclusively labels the vesicles that contain DNA with 5'PO 4 blunt-ended DNA breaks, such as those produced by the apoptotic CAD nuclease during apoptotic DNA degradation. The technique can be useful in studies of apoptosis involving microvesicles and exosomes.

  10. Monosaccharide transport in protein-depleted vesicles from erythrocyte membranes

    National Research Council Canada - National Science Library

    M A Zoccoli; G E Lienhard

    1977-01-01

    .... Based on comparisons between erythrocytes and vesicles with regard to specificity, temparture dependence, and effects of inhibitors, we conclude that sorbose uptake into the vesicles occurs by way...

  11. Low sodium diet (image)

    Science.gov (United States)

    ... for you. Look for these words on labels: low-sodium, sodium-free, no salt added, sodium-reduced, or ... for you. Look for these words on labels: low-sodium, sodium-free, no salt added, sodium-reduced, or ...

  12. A Nonconventional Model of Protocell-like Vesicles: Anionic Clay Surface-Mediated Formation from a Single-Tailed Amphiphile.

    Science.gov (United States)

    Du, Na; Song, Ruiying; Li, Haiping; Song, Shue; Zhang, Renjie; Hou, Wanguo

    2015-11-24

    We report a novel model system of precursor cellular membranes, self-assembled from micellar solution of a common anionic single-tailed amphiphile (STA), including sodium dodecyl sulfate (SDS) and sodium dodecylbenzenesulfonate (SDBS). The self-assembly process was mediated with solid surfaces of Mg2Al-CO3 hydrotalcite-like compound (HTlc), an anionic clay, in the absence of cosurfactants or any additives. The resultant STA vesicles were characterized using negative-staining and cryogenic transmission electron microscopies, as well as dynamic light scattering and steady state fluorescence techniques. Interestingly, the obtained STA vesicles displayed good stability even after the removal of the anionic clay surface (ACS), and a self-reproduction phenomenon was observed for the "preformed" STA vesicles when mixing with corresponding STA micellar solutions. More importantly, the micelle-to-vesicle transition for SDS could be still arisen in high-salinity artificial seawater under the ACS mediation. Instead of conventional fatty acid scenario, our finding provides another novel possible model for protocell-like vesicles, which are easily formed under the plausible prebiotic conditions.

  13. Bicarbonate sulfate exchange in canalicular rat liver plasma membrane vesicles

    Energy Technology Data Exchange (ETDEWEB)

    Meier, P.J.; Valantinas, J.; Hugentobler, G.; Rahm, I. (University Hospital, Zurich (Switzerland))

    1987-10-01

    The mechanism(s) and driving forces for biliary excretion of sulfate were investigated in canalicular rat liver plasma membrane vesicles (cLPM). Incubation of cLPM vesicles in the presence of an inside-to-outside (in, out) bicarbonate gradient but not pH or out-to-in sodium gradients, stimulated sulfate uptake 10-fold compared with the absence of bicarbonate and approximately 2-fold above sulfate equilibrium (overshoot). Initial rates of this bicarbonate gradient-driven ({sup 35}S)-sulfate uptake were saturable with increasing concentrations of sulfate and could be inhibited by probenecid, N-(4-azido-2-nitrophenyl)-2-aminoethylsulfonate, acetazolamide, furosemide, 4-acetamideo-4{prime}-isothiocyanostilbene-2,2{prime}-disulfonic acid, and 4,4{prime}-diisothiocyanostilbene-2,2{prime}-disulfonic acid (IC{sub 50}, {approximately}40 {mu}M). Cisinhibition of initial bicarbonate gradient-stimulated sulfate uptake and transstimulation of sulfate uptake in the absence of bicarbonate were observed with sulfate, thiosulfate, and oxalate but not with chloride, nitrate, phosphate, acetate, lactate, glutamate, aspartate, cholate, taurocholate, dehydrocholate, taurodehydrocholate, and reduced or oxidized glutathione. These findings indicate the presence of a sulfate (oxalate)-bicarbonate anion exchange system in canalicular rat liver plasma membranes. These findings support the concept that bicarbonate-sensitive transport system might play an important role in bile acid-independent canalicular bile formation.

  14. Sodium Taste During Sodium Appetite.

    Science.gov (United States)

    Norgren, Ralph

    2017-02-01

    Sodium appetite appears to be an excellent model to study the neural mechanisms of motivation. In this issue of Chemical Senses, experiments by St John (2016) challenge 2 hypotheses for how a systemic sodium deficit guides an animal to find and ingest more Na ions in the environment. Both hypotheses deal with modifications of the sensory neural code produced by Na(+) ions on the tongue. One envisions a change in the Na(+) signal amplitude. A reduction could make the strong Na(+) signals less aversive; an increase, weak signals more noticeable. The other hypothesis requires no changes in the identity or amplitude of the Na(+) signal, but a shift in its hedonic tone toward sweetness or reward. The results of the 3 behavioral experiments render both explanations unlikely but fail to suggest alternatives. © The Author 2016. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  15. Effectiveness of Chlorinated Water, Sodium Hypochlorite, Sodium ...

    African Journals Online (AJOL)

    This study evaluated the efficacy of chlorinated water, sodium hypochlorite solution, sodium chloride solution and sterile distilled water in eliminating pathogenic bacteria on the surfaces of raw vegetables. Lettuce vegetables were dipped in different concentrations of chlorinated water, sodium hypochlorite solution, sodium ...

  16. Extracellular vesicles as emerging intercellular communicasomes.

    Science.gov (United States)

    Yoon, Yae Jin; Kim, Oh Youn; Gho, Yong Song

    2014-10-01

    All living cells release extracellular vesicles having pleiotropic functions in intercellular communication. Mammalian extracellular vesicles, also known as exosomes and microvesicles, are spherical bilayered proteolipids composed of various bioactive molecules, including RNAs, DNAs, proteins, and lipids. Extracellular vesicles directly and indirectly control a diverse range of biological processes by transferring membrane proteins, signaling molecules, mRNAs, and miRNAs, and activating receptors of recipient cells. The active interaction of extracellular vesicles with other cells regulates various physiological and pathological conditions, including cancer, infectious diseases, and neurodegenerative disorders. Recent developments in high-throughput proteomics, transcriptomics, and lipidomics tools have provided ample data on the common and specific components of various types of extracellular vesicles. These studies may contribute to the understanding of the molecular mechanism involved in vesicular cargo sorting and the biogenesis of extracellular vesicles, and, further, to the identification of disease-specific biomarkers. This review focuses on the components, functions, and therapeutic and diagnostic potential of extracellular vesicles under various pathophysiological conditions.

  17. Structure of Amphiphilic Terpolymer Raspberry Vesicles

    Directory of Open Access Journals (Sweden)

    Yingying Guo

    2017-07-01

    Full Text Available Terpolymer raspberry vesicles contain domains of different chemical affinities. They are potential candidates as multi-compartment cargo carriers. Their efficacy depends on their stability and load capacity. Using a model star terpolymer system in an aqueous solution, a dissipative particle dynamic (DPD simulation is employed to investigate how equilibrium aggregate structures are affected by polymer concentration and pairwise interaction energy in a solution. It is shown that a critical mass of polymer is necessary for vesicle formation. The free energy of the equilibrium aggregates are calculated and the results show that the transition from micelles to vesicles is governed by the interactions between the longest solvophobic block and the solvent. In addition, the ability of vesicles to encapsulate solvent is assessed. It is found that reducing the interaction energy favours solvent encapsulation, although solvent molecules can permeate through the vesicle’s shell when repulsive interactions among monomers are low. Thus, one can optimize the loading capacity and the release rate of the vesicles by turning pairwise interaction energies of the polymer and the solvent. The ability to predict and control these aspects of the vesicles is an essential step towards designing vesicles for specific purposes.

  18. Spontaneous vesicle phase formation by pseudogemini surfactants in aqueous solutions.

    Science.gov (United States)

    Sun, Nan; Shi, Lijuan; Lu, Fei; Xie, Shuting; Zheng, Liqiang

    2014-08-14

    The phase behavior of a kind of pseudogemini surfactant in aqueous solutions, formed by the mixture of sodium dodecyl benzene sulfonate (SDBS) and butane-1,4-bis (methylimidazolium bromide) ([mim-C4-mim]Br2) or butane-1,4-bis(methylpyrrolidinium bromide) ([mpy-C4-mpy]Br2) in a molar ratio of 2 : 1, is reported in the present work. When [mim-C4-mim]Br2 or [mpy-C4-mpy]Br2 is mixed with SDBS in aqueous solutions, one cationic [mim-C4-mim]Br2 or [mpy-C4-mpy]Br2 molecule "bridges" two SDBS molecules by noncovalent interactions (e.g. electrostatic, π-π stacking, and σ-π interactions), behaving like a pseudogemini surfactant. Vesicles can be formed by this kind of pseudogemini surfactant, determined by freeze-fracture transmission electron microscopy (FF-TEM) or cryogenic-transmission electron microscopy (cryo-TEM) and dynamic light scattering (DLS). The mixed system of sodium dodecyl sulfate (SDS) with [mim-C4-mim]Br2 or [mpy-C4-mpy]Br2 was also constructed, and only micelles were observed. We infer that a pseudogemini surfactant is formed under the synergic effect of electrostatic, π-π stacking, and σ-π interactions in the SDBS/[mim-C4-mim]Br2/H2O system, while electrostatic attraction and hydrophobic interactions may provide the directional force for vesicle formation in the SDBS/[mpy-C4-mpy]Br2/H2O system.

  19. Illuminating the physiology of extracellular vesicles.

    Science.gov (United States)

    Choi, Hongyoon; Lee, Dong Soo

    2016-04-16

    Extracellular vesicles play a crucial role in intercellular communication by transmitting biological materials from donor cells to recipient cells. They have pathophysiologic roles in cancer metastasis, neurodegenerative diseases, and inflammation. Extracellular vesicles also show promise as emerging therapeutics, with understanding of their physiology including targeting, distribution, and clearance therefore becoming an important issue. Here, we review recent advances in methods for tracking and imaging extracellular vesicles in vivo and critically discuss their systemic distribution, targeting, and kinetics based on up-to-date evidence in the literature.

  20. Classification, Functions, and Clinical Relevance of Extracellular Vesicles

    NARCIS (Netherlands)

    van der Pol, Edwin; Böing, Anita N.; Harrison, Paul; Sturk, Augueste; Nieuwland, Rienk

    2012-01-01

    Both eukaryotic and prokaryotic cells release small, phospholipid-enclosed vesicles into their environment. Why do cells release vesicles? Initial studies showed that eukaryotic vesicles are used to remove obsolete cellular molecules. Although this release of vesicles is beneficial to the cell, the

  1. Vesicle-MaNiA: extracellular vesicles in liquid biopsy and cancer

    OpenAIRE

    Torrano, Veronica; Royo, Felix; Peinado, Héctor; Loizaga-Iriarte, Ana; Unda, Miguel; Falcón-Perez, Juan M.; Carracedo, Arkaitz

    2016-01-01

    Normal and tumor cells shed vesicles to the environment. Within the large family of extracellular vesicles, exosomes and microvesicles have attracted much attention in the recent years. Their interest ranges from mediators of cancer progression, inflammation, immune regulation and metastatic niche regulation, to non-invasive biomarkers of disease. In this respect, the procedures to purify and analyze extracellular vesicles have quickly evolved and represent a source of variability for data in...

  2. Hybrid, Nanoscale Phospholipid/Block Copolymer Vesicles

    Directory of Open Access Journals (Sweden)

    Bo Liedberg

    2013-09-01

    Full Text Available Hybrid phospholipid/block copolymer vesicles, in which the polymeric membrane is blended with phospholipids, display interesting self-assembly behavior, incorporating the robustness and chemical versatility of polymersomes with the softness and biocompatibility of liposomes. Such structures can be conveniently characterized by preparing giant unilamellar vesicles (GUVs via electroformation. Here, we are interested in exploring the self-assembly and properties of the analogous nanoscale hybrid vesicles (ca. 100 nm in diameter of the same composition prepared by film-hydration and extrusion. We show that the self-assembly and content-release behavior of nanoscale polybutadiene-b-poly(ethylene oxide (PB-PEO/1-palmitoyl-2-oleoyl-sn-glycero-3-phosphatidylcholine (POPC hybrid phospholipid/block copolymer vesicles can be tuned by the mixing ratio of the amphiphiles. In brief, these hybrids may provide alternative tools for drug delivery purposes and molecular imaging/sensing applications and clearly open up new avenues for further investigation.

  3. Stability of Spherical Vesicles in Electric Fields

    Science.gov (United States)

    2010-01-01

    The stability of spherical vesicles in alternating (ac) electric fields is studied theoretically for asymmetric conductivity conditions across their membranes. The vesicle deformation is obtained from a balance between the curvature elastic energies and the work done by the Maxwell stresses. The present theory describes and clarifies the mechanisms for the four types of morphological transitions observed experimentally on vesicles exposed to ac fields in the frequency range from 500 to 2 × 107 Hz. The displacement currents across the membranes redirect the electric fields toward the membrane normal to accumulate electric charges by the Maxwell−Wagner mechanism. These accumulated electric charges provide the underlying molecular mechanism for the morphological transitions of vesicles as observed on the micrometer scale. PMID:20575588

  4. Kinetic regulation of coated vesicle secretion

    CERN Document Server

    Foret, Lionel

    2008-01-01

    The secretion of vesicles for intracellular transport often rely on the aggregation of specialized membrane-bound proteins into a coat able to curve cell membranes. The nucleation and growth of a protein coat is a kinetic process that competes with the energy-consuming turnover of coat components between the membrane and the cytosol. We propose a generic kinetic description of coat assembly and the formation of coated vesicles, and discuss its implication to the dynamics of COP vesicles that traffic within the Golgi and with the Endoplasmic Reticulum. We show that stationary coats of fixed area emerge from the competition between coat growth and the recycling of coat components, in a fashion resembling the treadmilling of cytoskeletal filaments. We further show that the turnover of coat components allows for a highly sensitive switching mechanism between a quiescent and a vesicle producing membrane, upon a slowing down of the exchange kinetics. We claim that the existence of this switching behaviour, also tri...

  5. Mutations in Synaptojanin Disrupt Synaptic Vesicle Recycling

    OpenAIRE

    Harris, Todd W.; Hartwieg, Erika; Horvitz, H. Robert; Jorgensen, Erik M.

    2000-01-01

    Synaptojanin is a polyphosphoinositide phosphatase that is found at synapses and binds to proteins implicated in endocytosis. For these reasons, it has been proposed that synaptojanin is involved in the recycling of synaptic vesicles. Here, we demonstrate that the unc-26 gene encodes the Caenorhabditis elegans ortholog of synaptojanin. unc-26 mutants exhibit defects in vesicle trafficking in several tissues, but most defects are found at synaptic termini. Specifically, we observed defects in ...

  6. Concentration-Independent Spontaneously Forming Biomimetric Vesicles

    Science.gov (United States)

    Nieh, M.-P.; Harroun, T. A.; Raghunathan, V. A.; Glinka, C. J.; Katsaras, J.

    2003-10-01

    In this Letter we present small-angle neutron scattering data from a biomimetic system composed of the phospholipids dimyristoyl and dihexanoyl phosphorylcholine (DMPC and DHPC, respectively). Doping DMPC-DHPC multilamellar vesicles with either the negatively charged lipid dimyristoyl phosphorylglycerol (DMPG, net charge -1) or the divalent cation, calcium (Ca2+), leads to the spontaneous formation of energetically stabilized monodisperse unilamellar vesicles whose radii are concentration independent and in contrast with previous experimental observations.

  7. Labeling Extracellular Vesicles for Nanoscale Flow Cytometry

    OpenAIRE

    Aizea Morales-Kastresana; Bill Telford; Musich, Thomas A.; Katherine McKinnon; Cassandra Clayborne; Zach Braig; Ari Rosner; Thorsten Demberg; Watson, Dionysios C.; Karpova, Tatiana S.; Freeman, Gordon J.; DeKruyff, Rosemarie H.; Pavlakis, George N.; Masaki Terabe; Marjorie Robert-Guroff

    2017-01-01

    Extracellular vesicles (EVs), including exosomes and microvesicles, are 30?800?nm vesicles that are released by most cell types, as biological packages for intercellular communication. Their importance in cancer and inflammation makes EVs and their cargo promising biomarkers of disease and cell-free therapeutic agents. Emerging high-resolution cytometric methods have created a pressing need for efficient fluorescent labeling procedures to visualize and detect EVs. Suitable labels must be brig...

  8. Sodium in diet

    Science.gov (United States)

    Diet - sodium (salt); Hyponatremia - sodium in diet; Hypernatremia - sodium in diet; Heart failure - sodium in diet ... Too much sodium in the diet may lead to: High blood pressure in some people A serious buildup of fluid in people with heart failure , cirrhosis of ...

  9. Cellular Phenotype and Extracellular Vesicles: Basic and Clinical Considerations

    OpenAIRE

    Quesenberry, Peter J.; Goldberg, Laura R.; Aliotta, Jason M.; Mark S Dooner; Pereira, Mandy G.; Wen, Sicheng; Camussi, Giovanni

    2014-01-01

    Early work on platelet and erythrocyte vesicles interpreted the phenomena as a discard of material from cells. Subsequently, vesicles were studied as possible vaccines and, most recently, there has been a focus on the effects of vesicles on cell fate. Recent studies have indicated that extracellular vesicles, previously referred to as microvesicles or exosomes, have the capacity to change the phenotype of neighboring cells. Extensive work has shown that vesicles derived from either the lung o...

  10. Hierarchical unilamellar vesicles of controlled compositional heterogeneity.

    Directory of Open Access Journals (Sweden)

    Maik Hadorn

    Full Text Available Eukaryotic life contains hierarchical vesicular architectures (i.e. organelles that are crucial for material production and trafficking, information storage and access, as well as energy production. In order to perform specific tasks, these compartments differ among each other in their membrane composition and their internal cargo and also differ from the cell membrane and the cytosol. Man-made structures that reproduce this nested architecture not only offer a deeper understanding of the functionalities and evolution of organelle-bearing eukaryotic life but also allow the engineering of novel biomimetic technologies. Here, we show the newly developed vesicle-in-water-in-oil emulsion transfer preparation technique to result in giant unilamellar vesicles internally compartmentalized by unilamellar vesicles of different membrane composition and internal cargo, i.e. hierarchical unilamellar vesicles of controlled compositional heterogeneity. The compartmentalized giant unilamellar vesicles were subsequently isolated by a separation step exploiting the heterogeneity of the membrane composition and the encapsulated cargo. Due to the controlled, efficient, and technically straightforward character of the new preparation technique, this study allows the hierarchical fabrication of compartmentalized giant unilamellar vesicles of controlled compositional heterogeneity and will ease the development of eukaryotic cell mimics that resemble their natural templates as well as the fabrication of novel multi-agent drug delivery systems for combination therapies and complex artificial microreactors.

  11. Elastic energy of polyhedral bilayer vesicles.

    Science.gov (United States)

    Haselwandter, Christoph A; Phillips, Rob

    2011-06-01

    In recent experiments [M. Dubois, B. Demé, T. Gulik-Krzywicki, J.-C. Dedieu, C. Vautrin, S. Désert, E. Perez, and T. Zemb, Nature (London) 411, 672 (2001)] the spontaneous formation of hollow bilayer vesicles with polyhedral symmetry has been observed. On the basis of the experimental phenomenology it was suggested [M. Dubois, V. Lizunov, A. Meister, T. Gulik-Krzywicki, J. M. Verbavatz, E. Perez, J. Zimmerberg, and T. Zemb, Proc. Natl. Acad. Sci. USA 101, 15082 (2004)] that the mechanism for the formation of bilayer polyhedra is minimization of elastic bending energy. Motivated by these experiments, we study the elastic bending energy of polyhedral bilayer vesicles. In agreement with experiments, and provided that excess amphiphiles exhibiting spontaneous curvature are present in sufficient quantity, we find that polyhedral bilayer vesicles can indeed be energetically favorable compared to spherical bilayer vesicles. Consistent with experimental observations we also find that the bending energy associated with the vertices of bilayer polyhedra can be locally reduced through the formation of pores. However, the stabilization of polyhedral bilayer vesicles over spherical bilayer vesicles relies crucially on molecular segregation of excess amphiphiles along the ridges rather than the vertices of bilayer polyhedra. Furthermore, our analysis implies that, contrary to what has been suggested on the basis of experiments, the icosahedron does not minimize elastic bending energy among arbitrary polyhedral shapes and sizes. Instead, we find that, for large polyhedron sizes, the snub dodecahedron and the snub cube both have lower total bending energies than the icosahedron.

  12. Endothelial Extracellular Vesicles-Promises and Challenges.

    Science.gov (United States)

    Hromada, Carina; Mühleder, Severin; Grillari, Johannes; Redl, Heinz; Holnthoner, Wolfgang

    2017-01-01

    Extracellular vesicles, including exosomes, microparticles, and apoptotic bodies, are phospholipid bilayer-enclosed vesicles that have once been considered as cell debris lacking biological functions. However, they have recently gained immense interest in the scientific community due to their role in intercellular communication, immunity, tissue regeneration as well as in the onset, and progression of various pathologic conditions. Extracellular vesicles of endothelial origin have been found to play a versatile role in the human body, since they are on the one hand known to contribute to cardiovascular diseases, but on the other hand have also been reported to promote endothelial cell survival. Hence, endothelial extracellular vesicles hold promising therapeutic potential to be used as a new tool to detect as well as treat a great number of diseases. This calls for clinically approved, standardized, and efficient isolation and characterization protocols to harvest and purify endothelial extracellular vesicles. However, such methods and techniques to fulfill stringent requirements for clinical trials have yet to be developed or are not harmonized internationally. In this review, recent advances and challenges in the field of endothelial extracellular vesicle research are discussed and current problems and limitations regarding isolation and characterization are pointed out.

  13. Vesicles formed by mixed catanionic surfactants as novel pseudostationary phase in electrokinetic chromatography.

    Science.gov (United States)

    Lu, Jie; Ni, Xinjiong; Cao, Yuhua; Ma, Xinyu; Cao, Guangqun

    2014-09-12

    In this paper, a novel pseudostationary phase (PSP), the vesicle formed from octyltriethylammonium bromide (C8NE3Br) and sodium dodecyl benzene sulfonate (SDBS), has been developed in electrokinetic chromatography (EKC). Physicochemical parameters of the mixture of catanionic surfactants such as ζ potential and size of the aggregates were characterized as the molar ratio of C8NE3Br to SDBS varied from 2:8 to 8:2 and total concentration of surfactants fixed at 20mM. At any ratio mentioned above, ζ potential of mixture of catanionic surfactants remained negative. The absolute values of ζ potential were even larger than in only SDBS system as the molar ratio of C8NE3Br to SDBS less than 4:6, and they decreased as increasing the ratio of cationic surfactants. The size of the aggregates became smaller as the ratio was close to 1. Unexpectedly, the size was smallest at ratio of 3:7 and 6:4, instead of at 5:5. Notably, coagulation did not occur in the catanionic system at any proportion of each other. TEM testified the formation of vesicles. The performance of the vesicle as PSP was evaluated by separating eight kinds of corticosteroids with EKC, these analytes were separated completely without any additives. Compared with SDS microemulsion modified with ionic liquid (IL) and polymeric micelle, the novel vesicle PSP had better separation performances. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. Extracellular Vesicles in Metabolic Syndrome.

    Science.gov (United States)

    Martínez, M Carmen; Andriantsitohaina, Ramaroson

    2017-05-12

    Metabolic syndrome defines a cluster of interrelated risk factors for cardiovascular disease and diabetes mellitus. These factors include metabolic abnormalities, such as hyperglycemia, elevated triglyceride levels, low high-density lipoprotein cholesterol levels, high blood pressure, and obesity, mainly central adiposity. In this context, extracellular vesicles (EVs) may represent novel effectors that might help to elucidate disease-specific pathways in metabolic disease. Indeed, EVs (a terminology that encompasses microparticles, exosomes, and apoptotic bodies) are emerging as a novel mean of cell-to-cell communication in physiology and pathology because they represent a new way to convey fundamental information between cells. These microstructures contain proteins, lipids, and genetic information able to modify the phenotype and function of the target cells. EVs carry specific markers of the cell of origin that make possible monitoring their fluctuations in the circulation as potential biomarkers inasmuch their circulating levels are increased in metabolic syndrome patients. Because of the mixed components of EVs, the content or the number of EVs derived from distinct cells of origin, the mode of cell stimulation, and the ensuing mechanisms for their production, it is difficult to attribute specific functions as drivers or biomarkers of diseases. This review reports recent data of EVs from different origins, including endothelial, smooth muscle cells, macrophages, hepatocytes, adipocytes, skeletal muscle, and finally, those from microbiota as bioeffectors of message, leading to metabolic syndrome. Depicting the complexity of the mechanisms involved in their functions reinforce the hypothesis that EVs are valid biomarkers, and they represent targets that can be harnessed for innovative therapeutic approaches. © 2017 American Heart Association, Inc.

  15. A two phase field model for tracking vesicle-vesicle adhesion.

    Science.gov (United States)

    Gu, Rui; Wang, Xiaoqiang; Gunzburger, Max

    2016-11-01

    A multi-phase-field model for simulating the adhesion between two vesicles is constructed. Two phase field functions are introduced to simulate each of the two vesicles. An energy model is defined which accounts for the elastic bending energy of each vesicle and the contact potential energy between the two vesicles; the vesicle volume and surface area constraints are imposed using a penalty method. Numerical results are provided to verify the efficacy of our model and to provide visual illustrations of the different types of contact. The method can be adjusted to solve endocytosis problems by modifying the bending rigidity coefficients of the two elastic bending energies. The method can also be extended to simulate multi-cell adhesions, one example of which is erythrocyte rouleaux. A comparison with laboratory observations demonstrates the effectiveness of the multi-phase field approach.

  16. Insights into the self-reproduction of oleate vesicles

    Energy Technology Data Exchange (ETDEWEB)

    Stano, P [' Enrico Fermi' Centre, Compendio Viminale, 00184 Rome (Italy); Wehrli, E [Electron Microscopy Centre (EMEZ), Applied Physics Institute, ETH Hoenggerberg, 8093 Zurich (Switzerland); Luisi, P L [Biology Department, University of RomaTre, Viale Marconi 446, 00146 Rome (Italy)

    2006-08-23

    In view of the importance of vesicles as models for early cells, several groups have started work looking for conditions under which vesicles can undergo growth and division. Evidence for growth and division has been obtained with the help of ferritin-labelled vesicles; furthermore, it has been shown that in such processes the vesicle size distribution is largely conserved. In both cases, the data suggest that the process under study is mainly characterized by vesicle growth and eventually division into daughter vesicles. However, direct evidence for vesicle division has not been obtained. In this paper, mostly based on freeze-fracture electron microscopy, we describe conditions under which for the first time division intermediates can be trapped in the form of twin vesicles. This finding, together with supporting dynamic light scattering and fluorescence investigations, permits us to establish some additional points in the mechanism of vesicle self-reproduction.

  17. Mechanics of post-fusion exocytotic vesicle.

    Science.gov (United States)

    Stephens, Thomas; Wu, Zhanghan; Liu, Jian

    2017-05-23

    Exocytosis is an important cellular process controlled by metabolic signaling. It involves vesicle fusion to the plasma membrane, followed by the opening of a fusion pore, and the subsequent release of the vesicular lumen content into the extracellular space. While most modeling efforts focus on the events leading to membrane fusion, how the vesicular membrane remodels after fusing to plasma membrane remains unclear. This latter event dictates the nature and the efficiency of exocytotic vesicular secretions, and is thus critical for exocytotic function. We provide a generic membrane mechanical model to systematically study the fate of post-fusion vesicles. We show that while membrane stiffness favors full-collapse vesicle fusion into the plasma membrane, the intravesicular pressure swells the vesicle and causes the fusion pore to shrink. Dimensions of the vesicle and its associated fusion pore further modulate this mechanical antagonism. We systematically define the mechanical conditions that account for the full spectrum of the observed vesicular secretion modes. Our model therefore can serve as a unified theoretical framework that sheds light on the elaborate control mechanism of exocytosis.

  18. Astrocytic Vesicle Mobility in Health and Disease

    Directory of Open Access Journals (Sweden)

    Robert Zorec

    2013-05-01

    Full Text Available Astrocytes are no longer considered subservient to neurons, and are, instead, now understood to play an active role in brain signaling. The intercellular communication of astrocytes with neurons and other non-neuronal cells involves the exchange of molecules by exocytotic and endocytotic processes through the trafficking of intracellular vesicles. Recent studies of single vesicle mobility in astrocytes have prompted new views of how astrocytes contribute to information processing in nervous tissue. Here, we review the trafficking of several types of membrane-bound vesicles that are specifically involved in the processes of (i intercellular communication by gliotransmitters (glutamate, adenosine 5'-triphosphate, atrial natriuretic peptide, (ii plasma membrane exchange of transporters and receptors (EAAT2, MHC-II, and (iii the involvement of vesicle mobility carrying aquaporins (AQP4 in water homeostasis. The properties of vesicle traffic in astrocytes are discussed in respect to networking with neighboring cells in physiologic and pathologic conditions, such as amyotrophic lateral sclerosis, multiple sclerosis, and states in which astrocytes contribute to neuroinflammatory conditions.

  19. Mechanics of post-fusion exocytotic vesicle

    Science.gov (United States)

    Stephens, Thomas; Wu, Zhanghan; Liu, Jian

    2017-06-01

    Exocytosis is an important cellular process controlled by metabolic signaling. It involves vesicle fusion to the plasma membrane, followed by the opening of a fusion pore, and the subsequent release of the vesicular lumen content into the extracellular space. While most modeling efforts focus on the events leading to membrane fusion, how the vesicular membrane remodels after fusing to plasma membrane remains unclear. This latter event dictates the nature and the efficiency of exocytotic vesicular secretions, and is thus critical for exocytotic function. We provide a generic membrane mechanical model to systematically study the fate of post-fusion vesicles. We show that while membrane stiffness favors full-collapse vesicle fusion into the plasma membrane, the intravesicular pressure swells the vesicle and causes the fusion pore to shrink. Dimensions of the vesicle and its associated fusion pore further modulate this mechanical antagonism. We systematically define the mechanical conditions that account for the full spectrum of the observed vesicular secretion modes. Our model therefore can serve as a unified theoretical framework that sheds light on the elaborate control mechanism of exocytosis.

  20. EXTRACELLULAR VESICLES: CLASSIFICATION, FUNCTIONS AND CLINICAL RELEVANCE

    Directory of Open Access Journals (Sweden)

    A. V. Oberemko

    2014-12-01

    Full Text Available This review presents a generalized definition of vesicles as bilayer extracellular organelles of all celular forms of life: not only eu-, but also prokaryotic. The structure and composition of extracellular vesicles, history of research, nomenclature, their impact on life processes in health and disease are discussed. Moreover, vesicles may be useful as clinical instruments for biomarkers, and they are promising as biotechnological drug. However, many questions in this area are still unresolved and need to be addressed in the future. The most interesting from the point of view of practical health care represents a direction to study the effect of exosomes and microvesicles in the development and progression of a particular disease, the possibility of adjusting the pathological process by means of extracellular vesicles of a particular type, acting as an active ingredient. Relevant is the further elucidation of the role and importance of exosomes to the surrounding cells, tissues and organs at the molecular level, the prospects for the use of non-cellular vesicles as biomarkers of disease.

  1. Functionally polymerized surfactant vesicles: synthesis and characterization

    Energy Technology Data Exchange (ETDEWEB)

    Tundo, P.; Kippenberger, D.J.; Klahn, P.L.; Prieto, N.E.; Fendler, J.H.

    1982-01-27

    Bis(2-(10-undecenoyloxycarbony bromide, bis(2-(10-undecenoyloxycarbony (2-hydroxyethyl)methylammonium bromide, bis(2-(10-undecenoyloxycarbony acid, bis(2-(10-undecenoyloxycarbony allylbis(2-dodecanoyloxycarbon bromide, and dimethyl-n-hexadecyl (10-(p-vin decyl)ammonium bromide have been synthesized. The predominantly single compartment bilayer vesicles formed from these surfactants could be polymerized either by exposure to ultraviolet irradiation or by the use of azoisobutyronitrile as an initiator. The presence of vesicles (unpolymerized and polymeric) has been demonstrated by electron micrography, H/sup 1/ NMR, gel filtration, phase transition, turbidity changes, substrate entrapment, and permeability. Polymerized vesicles are considerably more stable and less permeable and have reduced rates of turbidity changes compared to their unpolymerized counterparts. 19 references.

  2. Directed vesicle transport by diffusio-osmosis

    Science.gov (United States)

    Michler, D.; Shahidzadeh, N.; Sprik, R.; Bonn, D.

    2015-04-01

    We present a study on surfactant vesicles that spontaneously move towards an oil droplet that is deposited on a glass substrate. Tracer particles in the surfactant solution show that the motion is not self-propelled: the vesicles are entrained by a macroscopic hydrodynamic flow. Measurements of the flow velocity suggest that the flow is of diffusio-osmotic nature. The surfactant is observed to move into the oil phase which creates a gradient in ion concentration in the vicinity of the droplet. As the diffusion coefficients of the surfactant's co- and counter-ions differ, a charge separation takes place and an electric field arises. This electric field then generates a hydrodynamic flow along the charged glass substrate in which the vesicles are entrained.

  3. Functionalization of Block Copolymer Vesicle Surfaces

    Directory of Open Access Journals (Sweden)

    Wolfgang Meier

    2011-01-01

    Full Text Available In dilute aqueous solutions certain amphiphilic block copolymers self-assemble into vesicles that enclose a small pool of water with a membrane. Such polymersomes have promising applications ranging from targeted drug-delivery devices, to biosensors, and nanoreactors. Interactions between block copolymer membranes and their surroundings are important factors that determine their potential biomedical applications. Such interactions are influenced predominantly by the membrane surface. We review methods to functionalize block copolymer vesicle surfaces by chemical means with ligands such as antibodies, adhesion moieties, enzymes, carbohydrates and fluorophores. Furthermore, surface-functionalization can be achieved by self-assembly of polymers that carry ligands at their chain ends or in their hydrophilic blocks. While this review focuses on the strategies to functionalize vesicle surfaces, the applications realized by, and envisioned for, such functional polymersomes are also highlighted.

  4. Electrohydrodynamics of a compound vesicle under an AC electric field.

    Science.gov (United States)

    Sinha, Kumari Priti; Thaokar, Rochish M

    2017-07-12

    Compound vesicles are relevant as simplified models for biological cells as well as in technological applications such as drug delivery. Characterization of these compound vesicles, especially the inner vesicle, remains a challenge. Similarly their response to electric field assumes importance in light of biomedical applications such as electroporation. Fields lower than that required for electroporation cause electrodeformation in vesicles and can be used to characterize their mechanical and electrical properties. A theoretical analysis of the electrohydrodynamics of a compound vesicle with outer vesicle of radius R o and an inner vesicle of radius [Formula: see text], is presented. A phase diagram for the compound vesicle is presented and elucidated using detailed plots of electric fields, free charges and electric stresses. The electrohydrodynamics of the outer vesicle in a compound vesicle shows a prolate-sphere and prolate-oblate-sphere shape transitions when the conductivity of the annular fluid is greater than the outer fluid, and vice-versa respectively, akin to single vesicle electrohydrodynamics reported in the literature. The inner vesicle in contrast shows sphere-prolate-sphere and sphere-prolate-oblate-sphere transitions when the inner fluid conductivity is greater and smaller than the annular fluid, respectively. Equations and methodology are provided to determine the bending modulus and capacitance of the outer as well as the inner membrane, thereby providing an easy way to characterize compound vesicles and possibly biological cells.

  5. Electrohydrodynamics of a compound vesicle under an AC electric field

    Science.gov (United States)

    Priti Sinha, Kumari; Thaokar, Rochish M.

    2017-07-01

    Compound vesicles are relevant as simplified models for biological cells as well as in technological applications such as drug delivery. Characterization of these compound vesicles, especially the inner vesicle, remains a challenge. Similarly their response to electric field assumes importance in light of biomedical applications such as electroporation. Fields lower than that required for electroporation cause electrodeformation in vesicles and can be used to characterize their mechanical and electrical properties. A theoretical analysis of the electrohydrodynamics of a compound vesicle with outer vesicle of radius R o and an inner vesicle of radius λ {{R}o} , is presented. A phase diagram for the compound vesicle is presented and elucidated using detailed plots of electric fields, free charges and electric stresses. The electrohydrodynamics of the outer vesicle in a compound vesicle shows a prolate-sphere and prolate-oblate-sphere shape transitions when the conductivity of the annular fluid is greater than the outer fluid, and vice-versa respectively, akin to single vesicle electrohydrodynamics reported in the literature. The inner vesicle in contrast shows sphere-prolate-sphere and sphere-prolate-oblate-sphere transitions when the inner fluid conductivity is greater and smaller than the annular fluid, respectively. Equations and methodology are provided to determine the bending modulus and capacitance of the outer as well as the inner membrane, thereby providing an easy way to characterize compound vesicles and possibly biological cells.

  6. Mechanism of the Association between Na+ Binding and Conformations at the Intracellular Gate in Neurotransmitter:Sodium Symporters*

    OpenAIRE

    Stolzenberg, Sebastian; Quick, Matthias; Zhao, Chunfeng; Gotfryd, Kamil; Khelashvili, George; Gether, Ulrik; Claus J Loland; Javitch, Jonathan A.; Noskov, Sergei; Weinstein, Harel; Shi, Lei

    2015-01-01

    Neurotransmitter:sodium symporters (NSSs) terminate neurotransmission by Na+-dependent reuptake of released neurotransmitters. Previous studies suggested that Na+-binding reconfigures dynamically coupled structural elements in an allosteric interaction network (AIN) responsible for function-related conformational changes, but the intramolecular pathway of this mechanism has remained uncharted. We describe a new approach for the modeling and analysis of intramolecular dynamics in the bacterial...

  7. Vesicle-MaNiA: extracellular vesicles in liquid biopsy and cancer.

    Science.gov (United States)

    Torrano, Veronica; Royo, Felix; Peinado, Héctor; Loizaga-Iriarte, Ana; Unda, Miguel; Falcón-Perez, Juan M; Carracedo, Arkaitz

    2016-08-01

    Normal and tumor cells shed vesicles to the environment. Within the large family of extracellular vesicles, exosomes and microvesicles have attracted much attention in the recent years. Their interest ranges from mediators of cancer progression, inflammation, immune regulation and metastatic niche regulation, to non-invasive biomarkers of disease. In this respect, the procedures to purify and analyze extracellular vesicles have quickly evolved and represent a source of variability for data integration in the field. In this review, we provide an updated view of the potential of exosomes and microvesicles as biomarkers and the available technologies for their isolation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. The role of extracellular vesicles in malaria biology and pathogenesis.

    Science.gov (United States)

    Sampaio, Natalia Guimaraes; Cheng, Lesley; Eriksson, Emily M

    2017-06-09

    In the past decade, research on the functions of extracellular vesicles in malaria has expanded dramatically. Investigations into the various vesicle types, from both host and parasite origin, has revealed important roles for extracellular vesicles in disease pathogenesis and susceptibility, as well as cell-cell communication and immune responses. Here, work relating to extracellular vesicles in malaria is reviewed, and the areas that remain unknown and require further investigations are highlighted.

  9. Adsorption of DOPC vesicles on hydrophobic substrates in the ...

    Indian Academy of Sciences (India)

    Administrator

    In the present study, the interaction between an intact DOPC vesicle and the hydropho- bic surface is mainly through van der Waals interac- tion. In presence of increasing concentrations of electrolytes, counter ions are present in the vicinity of the DOPC vesicle. As the vesicle approaches the solid substrate, the counter ions ...

  10. Single-vesicle imaging reveals different transport mechanisms between glutamatergic and GABAergic vesicles.

    Science.gov (United States)

    Farsi, Zohreh; Preobraschenski, Julia; van den Bogaart, Geert; Riedel, Dietmar; Jahn, Reinhard; Woehler, Andrew

    2016-02-26

    Synaptic transmission is mediated by the release of neurotransmitters, which involves exo-endocytotic cycling of synaptic vesicles. To maintain synaptic function, synaptic vesicles are refilled with thousands of neurotransmitter molecules within seconds after endocytosis, using the energy provided by an electrochemical proton gradient. However, it is unclear how transmitter molecules carrying different net charges can be efficiently sequestered while maintaining charge neutrality and osmotic balance. We used single-vesicle imaging to monitor pH and electrical gradients and directly showed different uptake mechanisms for glutamate and γ-aminobutyric acid (GABA) operating in parallel. In contrast to glutamate, GABA was exchanged for protons, with no other ions participating in the transport cycle. Thus, only a few components are needed to guarantee reliable vesicle filling with different neurotransmitters. Copyright © 2016, American Association for the Advancement of Science.

  11. Role of Outer Membrane Vesicles of Bacteria

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 20; Issue 8. Role of Outer Membrance Vesicles of Bacteria. M V Jagannadham M K Chattopadhyay. General Article Volume 20 Issue 8 ... Keywords. Outer membrane ves ic les (OMVs); secretion; communication; virulence; antibiotic resistance; vaccines.

  12. Vesicle Pools: Lessons from Adrenal Chromaffin Cells

    Directory of Open Access Journals (Sweden)

    David R Stevens

    2011-02-01

    Full Text Available The adrenal chromaffin cell serves as a model system to study fast Ca2+-dependent exocytosis. Membrane capacitance measurements in combination with Ca2+ uncaging offers a temporal resolution in the millisecond range and reveals that catecholamine release occurs in three distinct phases. Release of a readily releasable (RRP and a slowly releasable (SRP pool are followed by sustained release, due to maturation and release of vesicles which were not release-ready at the start of the stimulus. Trains of depolarizations, a more physiological stimulus, induce release from a small immediately releasable pool of vesicles residing adjacent to calcium channels, as well as from the RRP. The SRP is poorly activated by depolarization. A sequential model, in which non-releasable docked vesicles are primed to a slowly releasable state, and then further mature to the readily releasable state, has been proposed. The docked state, dependent on membrane proximity, requires SNAP-25, synaptotagmin and syntaxin. The ablation or modification of SNAP-25 and syntaxin, components of the SNARE complex, as well as of synaptotagmin, the calcium sensor, and modulators such complexins and Snapin alter the properties and/or magnitudes of different phases of release, and in particular can ablate the RRP. These results indicate that the composition of the SNARE complex and its interaction with modulatory molecules drives priming and provides a molecular basis for different pools of releasable vesicles.

  13. Extracellular vesicles: fundamentals and clinical relevance

    Directory of Open Access Journals (Sweden)

    Wael Nassar

    2015-01-01

    Full Text Available All types of cells of eukaryotic organisms produce and release small nanovesicles into their extracellular environment. Early studies have described these vesicles as ′garbage bags′ only to remove obsolete cellular molecules. Valadi and colleagues, in 2007, were the first to discover the capability of circulating extracellular vesicles (EVs to horizontally transfer functioning gene information between cells. These extracellular vesicles express components responsible for angiogenesis promotion, stromal remodeling, chemoresistance, genetic exchange, and signaling pathway activation through growth factor/receptor transfer. EVs represent an important mode of intercellular communication by serving as vehicles for transfer between cells of membrane and cytosolic proteins, lipids, signaling proteins, and RNAs. They contribute to physiology and pathology, and they have a myriad of potential clinical applications in health and disease. Moreover, vesicles can pass the blood-brain barrier and may perhaps even be considered as naturally occurring liposomes. These cell-derived EVs not only represent a central mediator of the disease microenvironment, but their presence in the peripheral circulation may serve as a surrogate for disease biopsies, enabling real-time diagnosis and disease monitoring. In this review, we′ll be addressing the characteristics of different types of extracellular EVs, as well as their clinical relevance and potential as diagnostic markers, and also define therapeutic options.

  14. Compartmentalization and Transport in Synthetic Vesicles

    Directory of Open Access Journals (Sweden)

    Christine eSchmitt

    2016-02-01

    Full Text Available Nano-scale vesicles have become a popular tool in life sciences. Besides liposomes that are generated from phospholipids of natural origin, polymersomes fabricated of synthetic block copolymers enjoy increasing popularity, as they represent more versatile membrane building blocks that can be selected based on their specific physicochemical properties, like permeability, stability or chemical reactivity.In this review, we focus on the application of simple and nested artificial vesicles in synthetic biology. First, we provide an introduction into the utilization of multi-compartmented vesosomes as compartmentalized nano-scale bioreactors. In the bottom-up development of protocells from vesicular nano-reactors, the specific exchange of pathway intermediates across compartment boundaries represents a bottleneck for future studies. To date, most compartmented bioreactors rely on unspecific exchange of substrates and products. This is either based on changes in permeability of the coblock polymer shell by physicochemical triggers or by the incorporation of unspecific porin proteins into the vesicle membrane. Since the incorporation of membrane transport proteins into simple and nested artificial vesicles offers the potential for specific exchange of substances between subcompartments, it opens new vistas in the design of protocells. Therefore we devote the main part of the review to summarize the technical advances in the use of phospholipids and block copolymers for the reconstitution of membrane proteins.

  15. Towards traceable size determination of extracellular vesicles

    NARCIS (Netherlands)

    Varga, Zoltán; Yuana, Yuana; Grootemaat, Anita E.; van der Pol, Edwin; Gollwitzer, Christian; Krumrey, Michael; Nieuwland, Rienk

    2014-01-01

    Extracellular vesicles (EVs) have clinical importance due to their roles in a wide range of biological processes. The detection and characterization of EVs are challenging because of their small size, low refractive index, and heterogeneity. In this manuscript, the size distribution of an

  16. Functional transferred DNA within extracellular vesicles

    Energy Technology Data Exchange (ETDEWEB)

    Cai, Jin [Department of Cardiology, Daping Hospital, The Third Military Medical University, Chongqing 400042 (China); Department of Neurology, Jinling Hospital, Nanjing University School of Medicine, Jiangsu Province (China); Wu, Gengze [Department of Cardiology, Daping Hospital, The Third Military Medical University, Chongqing 400042 (China); Jose, Pedro A. [Division of Nephrology, Department of Medicine and Physiology, University of Maryland, School of Medicine, Baltimore, MD 21201 (United States); Zeng, Chunyu, E-mail: Chunyuzeng01@163.com [Department of Cardiology, Daping Hospital, The Third Military Medical University, Chongqing 400042 (China)

    2016-11-15

    Extracellular vesicles (EVs) are small membrane vesicles including exosomes and shedding vesicles that mediated a cell-to-cell communication. EVs are released from almost all cell types under both physiological and pathological conditions and incorporate nuclear and cytoplasmic molecules for intercellular delivery. Besides protein, mRNA, and microRNA of these molecules, as recent studies show, specific DNA are prominently packaged into EVs. It appears likely that some of exosomes or shedding vesicles, bearing nuclear molecules are released upon bubble-like blebs. Specific interaction of EVs with susceptible recipients performs the uptake of EVs into the target cells, discharging their cargo including nuclear and cytoplasmic macromolecules into the cytosol. These findings expand the nucleic acid content of EVs to include increased levels of specific DNA. Thus, EVs contain a repertoire of genetic information available for horizontal gene transfer and potential use as blood biomarkers for cancer and atherosclerosis. In this review, the focus is on the characteristics, biological functions, and roles in diseases of DNA within EVs. - Highlights: • This review is focused on the DNA within EVs including its characteristics, biological functions, and roles in diseases. • It is clear that DNA within EVs might have important physiological and pathological roles in various diseases. • Knowledge in this area may provides us alternative methods for disease diagnosis or therapy in the future.

  17. Theory of Disk-to-Vesicle Transformation

    Science.gov (United States)

    Li, Jianfeng; Shi, An-Chang

    2009-03-01

    Self-assembled membranes from amphiphilic molecules, such as lipids and block copolymers, can assume a variety of morphologies dictated by energy minimization of system. The membrane energy is characterized by a bending modulus (κ), a Gaussian modulus (κG), and the line tension (γ) of the edge. Two basic morphologies of membranes are flat disks that minimize the bending energy at the cost of the edge energy, and enclosed vesicles that minimize the edge energy at the cost of bending energy. In our work, the transition from disk to vesicle is studied theoretically using the string method, which is designed to find the minimum energy path (MEP) or the most probable transition path between two local minima of an energy landscape. Previous studies of disk-to-vesicle transition usually approximate the transitional states by a series of spherical cups, and found that the spherical cups do not correspond to stable or meta-stable states of the system. Our calculation demonstrates that the intermediate shapes along the MEP are very different from spherical cups. Furthermore, some of these transitional states can be meta-stable. The disk-to-vesicle transition pathways are governed by two scaled parameters, κG/κ and γR0/4κ, where R0 is the radius of the disk. In particular, a meta-stable intermediate state is predicted, which may correspond to the open morphologies observed in experiments and simulations.

  18. Characterization of Extracellular Vesicles using Raman Spectroscopy

    NARCIS (Netherlands)

    Lee, Wooje; Nanou, Afroditi; Terstappen, Leonardus Wendelinus Mathias Marie; Rho, Hoon Suk; le Gac, Severine; Offerhaus, Herman L.

    2017-01-01

    In this research, we aim to characterize extracellular vesicles(EVs) with Confocal Raman spectroscopy to reveal relevant spectral lines that signify differences between EVs derived from different cell lines. In the first stage we performed confocal Raman measurements on various EV samples. For these

  19. Downregulation of surface sodium pumps by endocytosis during meiotic maturation of Xenopus laevis oocytes

    Energy Technology Data Exchange (ETDEWEB)

    Schmalzing, G.; Eckard, P.; Kroener, S.P.; Passow, H. (Max-Planck-Institut fuer Biophysik, Frankfurt (Germany, F.R.))

    1990-01-01

    During meiotic maturation, plasma membranes of Xenopus laevis oocytes completely lose the capacity to transport Na and K and to bind ouabain. To explore whether the downregulation might be due to an internalization of the sodium pump molecules, the intracellular binding of ouabain was determined. Selective permeabilization of the plasma membrane of mature oocytes (eggs) by digitonin almost failed to disclose ouabain binding sites. However, when the eggs were additionally treated with 0.02% sodium dodecyl sulfate (SDS) to permeabilize inner membranes, all sodium pumps present before maturation were recovered. Phosphorylation by (gamma-32P)ATP combined with SDS-polyacrylamide gel electrophoresis (PAGE) and autoradiography showed that sodium pumps were greatly reduced in isolated plasma membranes of eggs. According to sucrose gradient fractionation, maturation induced a shift of sodium pumps from the plasma membrane fraction to membranes of lower buoyant density with a protein composition different from that of the plasma membrane. Endocytosed sodium pumps identified on the sucrose gradient from (3H)ouabain bound to the cell surface before maturation could be phosphorylated with inorganic (32P)phosphate. The findings suggest that downregulation of sodium pumps during maturation is brought about by translocation of surface sodium pumps to an intracellular compartment, presumably endosomes. This contrasts the mechanism of downregulation of Na-dependent cotransport systems, the activities of which are reduced as a consequence of a maturation-induced depolarization of the membrane without a removal of the corresponding transporter from the plasma membrane.

  20. Genetically Controlled Fusion, Exocytosis and Fission of Artificial Vesicles

    DEFF Research Database (Denmark)

    Bönzli, Eva; Hadorn, Maik; De Lucrezia, Davide

    if a special class of viral proteins, termed fusogenic peptides, were added to the external medium. In the present work, we intend to develop genetically controlled fusion, fission and exocytosis of vesicles by the synthesis of peptides within vesicles. First, we enclosed synthesized peptides in vesicles...... to induce in a next step fusion of adjacent vesicles, fission and exocytosis of nested vesicles. Second, we will replace the peptides by an enclosed cell-free expression system to internally synthesize fusion peptides. To control the gene expression, different mechanisms are available, e.g. addition...... fusion, fission and exocytosis....

  1. Loading of Vesicles into Soft Amphiphilic Nanotubes using Osmosis.

    Science.gov (United States)

    Erne, Petra M; van Bezouwen, Laura S; Štacko, Peter; van Dijken, Derk Jan; Chen, Jiawen; Stuart, Marc C A; Boekema, Egbert J; Feringa, Ben L

    2015-12-07

    The facile assembly of higher-order nanoarchitectures from simple building blocks is demonstrated by the loading of vesicles into soft amphiphilic nanotubes using osmosis. The nanotubes are constructed from rigid interdigitated bilayers which are capped with vesicles comprising phospholipid-based flexible bilayers. When a hyperosmotic gradient is applied to these vesicle-capped nanotubes, the closed system loses water and the more flexible vesicle bilayer is pulled inwards. This leads to inclusion of vesicles inside the nanotubes without affecting the tube structure, showing controlled reorganization of the self-assembled multicomponent system upon a simple osmotic stimulus. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Coated vesicles as protein release mechanism in myeloma cells.

    Science.gov (United States)

    Trombetta, L D; Lazarus, S S

    An electron microscopic study was undertaken of the protein release mechanism within myeloma cells showing a very high degree of protein production. Smooth surfaced vesicles (50 millimicrons) were seen to originate from the outer margin of the perinuclear cistern. Similar vesicles were also associated with distended Golgi sacs. Possible function of these vesicles could not be determined. Coated vesicles (60 millimicrons) originated as evaginations from endoplasmic reticulum in the transitional region. They were present throughout the cytoplasm and were seen to fuse with the cell membrane discharging an electron dense material. These vesicles are, therefore, thought to transport protein from the rough endoplasmic reticulum and discharge it at the cell surface.

  3. Naproxen sodium overdose

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/002507.htm Naproxen sodium overdose To use the sharing features on this page, please enable JavaScript. Naproxen sodium is a nonsteroidal anti-inflammatory drug (NSAID) used ...

  4. Sodium Ferric Gluconate Injection

    Science.gov (United States)

    Sodium ferric gluconate injection is used to treat iron-deficiency anemia (a lower than normal number of ... are also receiving the medication epoetin (Epogen, Procrit). Sodium ferric gluconate injection is in a class of ...

  5. Diclofenac sodium overdose

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/002630.htm Diclofenac sodium overdose To use the sharing features on this page, please enable JavaScript. Diclofenac sodium is a prescription medicine used to relieve pain ...

  6. Interaction of insulin with SDS/CTAB catanionic Vesicles

    Energy Technology Data Exchange (ETDEWEB)

    Tah, Bidisha; Pal, Prabir; Talapatra, G.B., E-mail: spgbt@iacs.res.in

    2014-01-15

    In the present study, a novel method was used for entrapping the protein, insulin into the catanionic SDS/CTAB vesicle membrane. The anionic SDS and cationic CTAB formed catanionic vesicles at particular concentration (35:65 by volume). In this study, vesicle membrane can be considered as model membrane. The vesicle formation and entrapment efficiency depend on the pH of the aqueous solution. The insulin molecules have attached with the vesicular membrane at pH 7.0. However, at acidic pH, the vesicles were ruptured and the insulin did not entrap into the vesicle membrane, whereas at alkaline pH insulin became fibriller. The scanning electron microscope (SEM), Dynamic light scattering (DLS), and Zeta potential studies established the self-assembled structure formation of insulin and catanionic vesicles. To know the protein confirmations, Circular dichroism (CD) was also employed. The temperature dependent steady state and time resolved emission spectroscopy show that at room temperature (25 °C), apart from the 305 nm tyrosine fluorescence, a new emission peak at 450 nm was observed only in case of insulin-vesicle system, and was assigned as the tyrosine phosphorescence. This phosphorescence peak is the signature of the entrapment of insulin into the vesicle membrane. Highlights: • SDS-CTAB based catanionic vesicle has been fabricated. • Insulin has been successfully immobilized on these vesicles. • Immobilized insulin shows room temperature phosphorescence.

  7. Sodium sieving in children.

    NARCIS (Netherlands)

    Rusthoven, E.; Krediet, R.T.; Willems, H.L.; Monnens, L.A.H.; Schroder, C.H.

    2005-01-01

    Sodium sieving is a consequence of dissociation between the amount of water and sodium transported over the peritoneal membrane. This dissociation occurs in the presence of aquaporin-mediated water transport. Sieving of sodium can be used as a rough measure for aquaporin-mediated water transport.

  8. Sodium sieving in children

    NARCIS (Netherlands)

    Rusthoven, Esther; Krediet, Raymond T.; Willems, Hans L.; Monnens, Leo A.; Schröder, Cornelis H.

    2005-01-01

    Sodium sieving is a consequence of dissociation between the amount of water and sodium transported over the peritoneal membrane. This dissociation occurs in the presence of aquaporin-mediated water transport. Sieving of sodium can be used as a rough measure for aquaporin-mediated water transport.

  9. Soft vesicles in the synthesis of hard materials.

    Science.gov (United States)

    Dong, Renhao; Liu, Weimin; Hao, Jingcheng

    2012-04-17

    Vesicles of surfactants in aqueous solution have received considerable attention because of their use as simple model systems for biological membranes and their applications in various fields including colloids, pharmaceuticals, and materials. Because of their architecture, vesicles could prove useful as "soft" templates for the synthesis of "hard materials". The vesicle phase, however, has been challenging and difficult to work with in the construction of hard materials. In the solution-phase synthesis of various inorganic or macromolecular materials, templating methods provide a powerful strategy to control the size, morphology, and composition of the resulting micro- and nanostructures. In comparison with hard templates, soft templates are generally constructed using amphiphilic molecules, especially surfactants and amphiphilic polymers. These types of compounds offer advantages including the wide variety of available templates, simple fabrication processes under mild conditions, and easy removal of the templates with less damage to the final structures. Researchers have used many ordered molecular aggregates such as vesicles, micelles, liquid crystals, emulsion droplets, and lipid nanotubes as templates or structure-directing agents to control the synthesis or assembly hard micro- and nanomaterials composed from inorganic compounds or polymers. In addition to their range of sizes and morphologies, vesicles present unique structures that can simultaneously supply different microenvironments for the growth and assembly of hard materials: the inner chamber of vesicles, the outer surface of the vesicles, and the space between bilayers. Two main approaches for applying vesicles in the field of hard materials have been explored: (i) in situ synthesis of micro- or nanomaterials within a specific microenvironment by vesicle templating and (ii) the assembly or incorporation of guest materials during the formation of vesicles. This Account provides an in-depth look at

  10. Ammonium ion substitutes for K/sup +/ in ATP-dependent Na/sup +/ transport by basolateral membrane vesicles

    Energy Technology Data Exchange (ETDEWEB)

    Towle, D.W.; Hoelleland, T.

    1987-03-01

    Ion-transporting cells from posterior gills of blue crabs (Callinectes sapidus) acclimated to low salinity were used as starting material for the preparation of microsomal membrane vesicles by density gradient centrifugation. The Na/sup +/-K/sup +/-adenosinetriphosphatase (ATPase)-enriched basolateral vesicles were loaded with KCl- or NH/sub 4//sup +/-containing medium by dilution and centrifugation, and initial rates of /sup 22/Na/sup +/ uptake into the vesicles were measured by a rapid filtration procedure. Varying the extravesicular sucrose concentration altered equilibrium uptake of /sup 22/Na/sup +/, indicating the existence of osmotically sensitive vesicles. Monensin, a sodium-specific ionophore, enhanced passive uptake of /sup 22/Na/sup +/ across the vesicle membrane in the absence of ATP. With 100 mM KCl in the intravesicular medium, addition of ATP to the extravesicular medium increased initial rates of /sup 22/Na/sup +/ uptake 10- to 20-fold over levels measured without ATP. A nonhydrolyzable ATP analog failed to stimulate /sup 22/Na/sup +/ uptake. Intravesicular K/sup +/ could be replaced by NH/sub 4//sup +/ but not by choline. With NH/sub 4//sup +/ as counterion, Na/sup +/ transport was inhibited by digitoxin, but valinomycin had no effect. A study of the kinetic effects of intravesicular K/sup +/ and NH/sub 4//sup +/ on initial rates of /sup 22/Na/sup +/ uptake indicated the existence of two classes of binding sites, one responding to counterion concentrations in the millimolar range and a second class responding to counterion concentrations over 50 mM. The results indicate that ATP-dependent /sup 22/Na/sup +/ uptake by membrane vesicles from Callinectes sapidus gill, mediated by Na/sup +/-K/sup +/-ATPase, can utilize either K/sup +/ or NH/sub 4//sup +/ as counterion.

  11. Signaling by Extracellular Vesicles Advances Cancer Hallmarks.

    Science.gov (United States)

    Kanada, Masamitsu; Bachmann, Michael H; Contag, Christopher H

    2016-02-01

    Mammalian cells secrete various extracellular vesicles (EVs; exosomes, microvesicles, and apoptotic bodies) that differ in biogenesis, composition, and function. Each vesicle type can originate from normal or cancerous cells, transfer molecular cargo to both neighboring and distant cells, and modulate cellular behaviors involved in eubiology and pathology, such as tumor development. Here, we review evidence for the role of EVs in the establishment and maintenance of cancer hallmarks, including sustaining proliferative signaling, evading growth suppression, resisting cell death, reprogramming energy metabolism, acquiring genomic instability, and remodeling the tumor microenvironment. We also discuss how EVs are implicated in the induction of angiogenesis, control of cellular invasion, initiation of premetastatic niches, maintenance of inflammation, and evasion of immune surveillance. The deeper understanding of the biology of EVs and their contribution to the development and progression of tumors is leading to new opportunities in the diagnosis and treatment of cancer. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. Seminal vesicle cystadenoma: a rare clinical perspective.

    Science.gov (United States)

    Lorber, Gideon; Pizov, Galina; Gofrit, Ofer N; Pode, Dov

    2011-08-01

    A 52-yr-old man presented with severe obstructive urinary symptoms. Ten years earlier, a digital rectal examination disclosed a small mass above the prostate, and a computed tomography (CT) scan showed a 3.5-cm cystic tumor of the right seminal vesicle. He had been followed conservatively elsewhere. Reevaluation of the mass with a CT scan and magnetic resonance imaging showed that the mass had grown to a maximal diameter of 14 cm. A transabdominal needle biopsy revealed benign fibromuscular tissue. The tumor was then resected by an open transvesical approach. Pathology was consistent with a benign seminal vesicle cystadenoma. The natural history, pathology, and surgical approach are described. Copyright © 2009 European Association of Urology. Published by Elsevier B.V. All rights reserved.

  13. Docking of secretory vesicles is syntaxin dependent.

    Directory of Open Access Journals (Sweden)

    Heidi de Wit

    Full Text Available Secretory vesicles dock at the plasma membrane before they undergo fusion. Molecular docking mechanisms are poorly defined but believed to be independent of SNARE proteins. Here, we challenged this hypothesis by acute deletion of the target SNARE, syntaxin, in vertebrate neurons and neuroendocrine cells. Deletion resulted in fusion arrest in both systems. No docking defects were observed in synapses, in line with previous observations. However, a drastic reduction in morphologically docked secretory vesicles was observed in chromaffin cells. Syntaxin-deficient chromaffin cells showed a small reduction in total and plasma membrane staining for the docking factor Munc18-1, which appears insufficient to explain the drastic reduction in docking. The sub-membrane cortical actin network was unaffected by syntaxin deletion. These observations expose a docking role for syntaxin in the neuroendocrine system. Additional layers of regulation may have evolved to make syntaxin redundant for docking in highly specialized systems like synaptic active zones.

  14. Vitrification of Germinal Vesicle Stage Oocytes

    OpenAIRE

    ABE, Yasuyuki; AONO, Nobuya; Hara, Kenshiro; Matsumoto, Hiromichi; BAKHTIYARI, Mehrdad; Sasada, Hiroshi; Sato, Eimei

    2004-01-01

    In order to cryopreserve germinal vesicle (GV) stage oocytes, we first need to develop a novel container for keeping large quantities of GV oocytes, because of collecting them as cumulus oocytes complexes (COCs) that have bigger size and larger volume than oocytes themselves, and second modify a protocol for optimizing vitrification of them. In this mini-review, we describe our recent progress for attaining these objectives. When 65 bovine COCs having GV oocytes could be placed on a sheet of ...

  15. Inflammatory Stroke Extracellular Vesicles Induce Macrophage Activation.

    Science.gov (United States)

    Couch, Yvonne; Akbar, Naveed; Davis, Simon; Fischer, Roman; Dickens, Alex M; Neuhaus, Ain A; Burgess, Annette I; Rothwell, Peter M; Buchan, Alastair M

    2017-08-01

    Extracellular vesicles (EVs) are protein-lipid complexes released from cells, as well as actively exocytosed, as part of normal physiology, but also during pathological processes such as those occurring during a stroke. Our aim was to determine the inflammatory potential of stroke EVs. EVs were quantified and analyzed in the sera of patients after an acute stroke (inflammation in immune cells. © 2017 American Heart Association, Inc.

  16. A readily retrievable pool of synaptic vesicles

    OpenAIRE

    Hua, Y; Sinha, R.; Thiel, C.; Schmidt, R.; Hueve, J.; Martens, H.; Hell, S.; Egner, A.; Klingauf, J.

    2011-01-01

    Abstract Although clathrin-mediated endocytosis (CME) is thought to be the predominant mechanism of synaptic vesicle (SV) recycling, it seems to be too slow for fast recycling. Therefore, it was suggested that a pre-sorted and pre-assembled pool of SV proteins on the presynaptic membrane might support a first wave of fast CME. In this study we monitored the temporal dynamics of such a 'readily retrievable pool' of SV proteins in rat hippocampal neurons using a novel probe. Applying...

  17. Endothelial microparticles: Sophisticated vesicles modulating vascular function

    Science.gov (United States)

    Curtis, Anne M; Edelberg, Jay; Jonas, Rebecca; Rogers, Wade T; Moore, Jonni S; Syed, Wajihuddin; Mohler, Emile R

    2015-01-01

    Endothelial microparticles (EMPs) belong to a family of extracellular vesicles that are dynamic, mobile, biological effectors capable of mediating vascular physiology and function. The release of EMPs can impart autocrine and paracrine effects on target cells through surface interaction, cellular fusion, and, possibly, the delivery of intra-vesicular cargo. A greater understanding of the formation, composition, and function of EMPs will broaden our understanding of endothelial communication and may expose new pathways amenable for therapeutic manipulation. PMID:23892447

  18. Development, characterization, and skin delivery studies of related ultradeformable vesicles: transfersomes, ethosomes, and transethosomes.

    Science.gov (United States)

    Ascenso, Andreia; Raposo, Sara; Batista, Cátia; Cardoso, Pedro; Mendes, Tiago; Praça, Fabíola Garcia; Bentley, Maria Vitória Lopes Badra; Simões, Sandra

    2015-01-01

    Ultradeformable vesicles (UDV) have recently become a promising tool for the development of improved and innovative dermal and transdermal therapies. The aim of this work was to study three related UDV: transfersomes, ethosomes, and transethosomes for the incorporation of actives of distinct polarities, namely, vitamin E and caffeine, and to evaluate the effect of the carrier on skin permeation and penetration. These actives were incorporated in UDV formulations further characterized for vesicles imaging by transmission electron microscopy; mean vesicle size and polydispersity index by photon correlation spectroscopy; zeta potential by laser-Doppler anemometry; deformability by pressure-driven transport; and incorporation efficiency (IE) after actives quantification by high-performance liquid chromatography. Topical delivery studies were performed in order to compare UDV formulations regarding the release, skin permeation, and penetration profiles. All UDV formulations showed size values within the expected range, except transethosomes prepared by "transfersomal method", for which size was smaller than 100 nm in contrast to that obtained for vesicles prepared by "ethosomal method". Zeta potential was negative and higher for formulations containing sodium cholate. The IE was much higher for vitamin E- than caffeine-loaded UDV as expected. For flux measurements, the following order was obtained: transethosomes (TE) > ethosomes (E) ≥ transfersomes (T). This result was consistent with the release and skin penetration profiles for Vitamin E-loaded UDV. However, the releasing results were totally the opposite for caffeine-loaded UDV, which might be explained by the solubility and thermodynamic activity of this active in each formulation instead of the UDV deformability attending to the higher non-incorporated fraction of caffeine. Anyway, a high skin penetration and permeation for all caffeine-loaded UDV were obtained. Transethosomes were more deformable than ethosomes

  19. ATP: The crucial component of secretory vesicles.

    Science.gov (United States)

    Estévez-Herrera, Judith; Domínguez, Natalia; Pardo, Marta R; González-Santana, Ayoze; Westhead, Edward W; Borges, Ricardo; Machado, José David

    2016-07-12

    The colligative properties of ATP and catecholamines demonstrated in vitro are thought to be responsible for the extraordinary accumulation of solutes inside chromaffin cell secretory vesicles, although this has yet to be demonstrated in living cells. Because functional cells cannot be deprived of ATP, we have knocked down the expression of the vesicular nucleotide carrier, the VNUT, to show that a reduction in vesicular ATP is accompanied by a drastic fall in the quantal release of catecholamines. This phenomenon is particularly evident in newly synthesized vesicles, which we show are the first to be released. Surprisingly, we find that inhibiting VNUT expression also reduces the frequency of exocytosis, whereas the overexpression of VNUT drastically increases the quantal size of exocytotic events. To our knowledge, our data provide the first demonstration that ATP, in addition to serving as an energy source and purinergic transmitter, is an essential element in the concentration of catecholamines in secretory vesicles. In this way, cells can use ATP to accumulate neurotransmitters and other secreted substances at high concentrations, supporting quantal transmission.

  20. Detection of platelet vesicles by flow cytometry.

    Science.gov (United States)

    Nolan, John P; Jones, Jennifer C

    2017-05-01

    The composition and function of platelet-derived extracellular vesicles (EVs) in health and in disease are a major topic of investigation in biomedical research. However, efforts to delineate specific molecular repertoires and roles for different types of EVs in the circulation are limited not only by the lack of flow cytometers capable of analyzing submicron- and nano-materials across the full size spectrum of plasma EVs, but also by the lack of standardized methods and reference materials that would permit inter-laboratory reproducibility for these analyses. In this review, we summarize the flow cytometry of EVs, with a focus on platelet vesicles in plasma. In addition to delineating the basic principles that govern what precautions must be considered when using flow cytometry for the analysis of platelet vesicles, we provide an overview for how to standardize, control, annotate, and report EV flow cytometry data reproducibly, while looking forward to a next generation of high sensitivity instruments for the analysis of EVs and other submicron biomaterials in the circulation.

  1. Routes and mechanisms of extracellular vesicle uptake

    Directory of Open Access Journals (Sweden)

    Laura Ann Mulcahy

    2014-08-01

    Full Text Available Extracellular vesicles (EVs are small vesicles released by donor cells that can be taken up by recipient cells. Despite their discovery decades ago, it has only recently become apparent that EVs play an important role in cell-to-cell communication. EVs can carry a range of nucleic acids and proteins which can have a significant impact on the phenotype of the recipient. For this phenotypic effect to occur, EVs need to fuse with target cell membranes, either directly with the plasma membrane or with the endosomal membrane after endocytic uptake. EVs are of therapeutic interest because they are deregulated in diseases such as cancer and they could be harnessed to deliver drugs to target cells. It is therefore important to understand the molecular mechanisms by which EVs are taken up into cells. This comprehensive review summarizes current knowledge of EV uptake mechanisms. Cells appear to take up EVs by a variety of endocytic pathways, including clathrin-dependent endocytosis, and clathrin-independent pathways such as caveolin-mediated uptake, macropinocytosis, phagocytosis, and lipid raft–mediated internalization. Indeed, it seems likely that a heterogeneous population of EVs may gain entry into a cell via more than one route. The uptake mechanism used by a given EV may depend on proteins and glycoproteins found on the surface of both the vesicle and the target cell. Further research is needed to understand the precise rules that underpin EV entry into cells.

  2. Major involvement of Na(+) -dependent multivitamin transporter (SLC5A6/SMVT) in uptake of biotin and pantothenic acid by human brain capillary endothelial cells.

    Science.gov (United States)

    Uchida, Yasuo; Ito, Katsuaki; Ohtsuki, Sumio; Kubo, Yoshiyuki; Suzuki, Takashi; Terasaki, Tetsuya

    2015-07-01

    The purpose of this study was to clarify the expression of Na(+) -dependent multivitamin transporter (SLC5A6/SMVT) and its contribution to the supply of biotin and pantothenic acid to the human brain via the blood-brain barrier. DNA microarray and immunohistochemical analyses confirmed that SLC5A6 is expressed in microvessels of human brain. The absolute expression levels of SLC5A6 protein in isolated human and monkey brain microvessels were 1.19 and 0.597 fmol/μg protein, respectively, as determined by a quantitative targeted absolute proteomics technique. Using an antibody-free method established by Kubo et al. (2015), we found that SLC5A6 was preferentially localized at the luminal membrane of brain capillary endothelium. Knock-down analysis using SLC5A6 siRNA showed that SLC5A6 accounts for 88.7% and 98.6% of total [(3) H]biotin and [(3) H]pantothenic acid uptakes, respectively, by human cerebral microvascular endothelial cell line hCMEC/D3. SLC5A6-mediated transport in hCMEC/D3 was markedly inhibited not only by biotin and pantothenic acid, but also by prostaglandin E2, lipoic acid, docosahexaenoic acid, indomethacin, ketoprofen, diclofenac, ibuprofen, phenylbutazone, and flurbiprofen. This study is the first to confirm expression of SLC5A6 in human brain microvessels and to provide evidence that SLC5A6 is a major contributor to luminal uptake of biotin and pantothenic acid at the human blood-brain barrier. In humans, it was unclear (not concluded) about what transport system at the blood-brain barrier (BBB) is responsible for the brain uptakes of two vitamins, biotin and pantothenic acid, which are necessary for brain proper function. This study clarified for the first time that the solute carrier 5A6/Na(+) -dependent multivitamin transporter SLC5A6/SMVT is responsible for the supplies of biotin and pantothenic acid into brain across the BBB in humans. DHA, docosahexaenoic acid; NSAID, non-steroidal anti-inflammatory drug; PGE2, prostaglandin E2. © 2015

  3. Extracellular Vesicles in Renal Diseases: More than Novel Biomarkers?

    Science.gov (United States)

    Erdbrügger, Uta; Le, Thu H

    2016-01-01

    Extracellular vesicles from the urine and circulation have gained significant interest as potential diagnostic biomarkers in renal diseases. Urinary extracellular vesicles contain proteins from all sections of the nephron, whereas most studied circulating extracellular vesicles are derived from platelets, immune cells, and the endothelium. In addition to their diagnostic role as markers of kidney and vascular damage, extracellular vesicles may have functional significance in renal health and disease by facilitating communication between cells and protecting against kidney injury and bacterial infection in the urinary tract. However, the current understanding of extracellular vesicles has derived mostly from studies with very small numbers of patients or in vitro data. Moreover, accurate assessment of these vesicles remains a challenge, in part because of a lack of consensus in the methodologies to measure extracellular vesicles and the inability of most techniques to capture the entire size range of these vesicles. However, newer techniques and standardized protocols to improve the detection of extracellular vesicles are in development. A clearer understanding of the composition and biology of extracellular vesicles will provide insights into their pathophysiologic, diagnostic, and therapeutic roles. Copyright © 2016 by the American Society of Nephrology.

  4. Extracellular vesicles in cardiovascular disease: are they Jedi or Sith?

    Science.gov (United States)

    Osteikoetxea, Xabier; Németh, Andrea; Sódar, Barbara W; Vukman, Krisztina V; Buzás, Edit Irén

    2016-06-01

    In the recent past, extracellular vesicles have become recognized as important players in cell biology and biomedicine. Extracellular vesicles, including exosomes, microvesicles and apoptotic bodies, are phospholipid bilayer-enclosed structures found to be secreted by most if not all cells. Extracellular vesicle secretion represents a universal and highly conserved active cellular function. Importantly, increasing evidence supports that extracellular vesicles may serve as biomarkers and therapeutic targets or tools in human diseases. Cardiovascular disease undoubtedly represents one of the most intensely studied and rapidly growing areas of the extracellular vesicle field. However, in different studies related to cardiovascular disease, extracellular vesicles have been shown to exert diverse and sometimes discordant biological effects. Therefore, it might seem a puzzle whether these vesicles are in fact beneficial or detrimental to cardiovascular health. In this review we provide a general introduction to extracellular vesicles and an overview of their biological roles in cardiovascular diseases. Furthermore, we aim to untangle the various reasons for the observed discrepancy in biological effects of extracellular vesicles in cardiovascular diseases. To this end, we provide several examples that demonstrate that the observed functional diversity is in fact due to inherent differences among various types of extracellular vesicles. © 2016 The Authors. The Journal of Physiology © 2016 The Physiological Society.

  5. Cerebrospinal fluid sodium rhythms

    Directory of Open Access Journals (Sweden)

    Johnson Benjamin

    2010-01-01

    Full Text Available Abstract Background Cerebrospinal fluid (CSF sodium levels have been reported to rise during episodic migraine. Since migraine frequently starts in early morning or late afternoon, we hypothesized that natural sodium chronobiology may predispose susceptible persons when extracellular CSF sodium increases. Since no mammalian brain sodium rhythms are known, we designed a study of healthy humans to test if cation rhythms exist in CSF. Methods Lumbar CSF was collected every ten minutes at 0.1 mL/min for 24 h from six healthy participants. CSF sodium and potassium concentrations were measured by ion chromatography, total protein by fluorescent spectrometry, and osmolarity by freezing point depression. We analyzed cation and protein distributions over the 24 h period and spectral and permutation tests to identify significant rhythms. We applied the False Discovery Rate method to adjust significance levels for multiple tests and Spearman correlations to compare sodium fluctuations with potassium, protein, and osmolarity. Results The distribution of sodium varied much more than potassium, and there were statistically significant rhythms at 12 and 1.65 h periods. Curve fitting to the average time course of the mean sodium of all six subjects revealed the lowest sodium levels at 03.20 h and highest at 08.00 h, a second nadir at 09.50 h and a second peak at 18.10 h. Sodium levels were not correlated with potassium or protein concentration, or with osmolarity. Conclusion These CSF rhythms are the first reports of sodium chronobiology in the human nervous system. The results are consistent with our hypothesis that rising levels of extracellular sodium may contribute to the timing of migraine onset. The physiological importance of sodium in the nervous system suggests that these rhythms may have additional repercussions on ultradian functions.

  6. Neuronal Depolarization Drives Increased Dopamine Synaptic Vesicle Loading via VGLUT.

    Science.gov (United States)

    Aguilar, Jenny I; Dunn, Matthew; Mingote, Susana; Karam, Caline S; Farino, Zachary J; Sonders, Mark S; Choi, Se Joon; Grygoruk, Anna; Zhang, Yuchao; Cela, Carolina; Choi, Ben Jiwon; Flores, Jorge; Freyberg, Robin J; McCabe, Brian D; Mosharov, Eugene V; Krantz, David E; Javitch, Jonathan A; Sulzer, David; Sames, Dalibor; Rayport, Stephen; Freyberg, Zachary

    2017-08-30

    The ability of presynaptic dopamine terminals to tune neurotransmitter release to meet the demands of neuronal activity is critical to neurotransmission. Although vesicle content has been assumed to be static, in vitro data increasingly suggest that cell activity modulates vesicle content. Here, we use a coordinated genetic, pharmacological, and imaging approach in Drosophila to study the presynaptic machinery responsible for these vesicular processes in vivo. We show that cell depolarization increases synaptic vesicle dopamine content prior to release via vesicular hyperacidification. This depolarization-induced hyperacidification is mediated by the vesicular glutamate transporter (VGLUT). Remarkably, both depolarization-induced dopamine vesicle hyperacidification and its dependence on VGLUT2 are seen in ventral midbrain dopamine neurons in the mouse. Together, these data suggest that in response to depolarization, dopamine vesicles utilize a cascade of vesicular transporters to dynamically increase the vesicular pH gradient, thereby increasing dopamine vesicle content. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Human mammospheres secrete hormone-regulated active extracellular vesicles.

    Directory of Open Access Journals (Sweden)

    Esperanza Gonzalez

    Full Text Available Breast cancer is a leading cause of cancer-associated death worldwide. One of the most important prognostic factors for survival is the early detection of the disease. Recent studies indicate that extracellular vesicles may provide diagnostic information for cancer management. We demonstrate the secretion of extracellular vesicles by primary breast epithelial cells enriched for stem/progenitor cells cultured as mammospheres, in non-adherent conditions. Using a proteomic approach we identified proteins contained in these vesicles whose expression is affected by hormonal changes in the cellular environment. In addition, we showed that these vesicles are capable of promoting changes in expression levels of genes involved in epithelial-mesenchymal transition and stem cell markers. Our findings suggest that secreted extracellular vesicles could represent potential diagnostic and/or prognostic markers for breast cancer and support a role for extracellular vesicles in cancer progression.

  8. Gram-negative and Gram-positive bacterial extracellular vesicles.

    Science.gov (United States)

    Kim, Ji Hyun; Lee, Jaewook; Park, Jaesung; Gho, Yong Song

    2015-04-01

    Like mammalian cells, Gram-negative and Gram-positive bacteria release nano-sized membrane vesicles into the extracellular environment either in a constitutive manner or in a regulated manner. These bacterial extracellular vesicles are spherical bilayered proteolipids enriched with bioactive proteins, lipids, nucleic acids, and virulence factors. Recent progress in this field supports the critical pathophysiological functions of these vesicles in both bacteria-bacteria and bacteria-host interactions. This review provides an overview of the current understanding on Gram-negative and Gram-positive bacterial extracellular vesicles, especially regarding the biogenesis, components, and functions in poly-species communities. We hope that this review will stimulate additional research in this emerging field of bacterial extracellular vesicles and contribute to the development of extracellular vesicle-based diagnostic tools and effective vaccines against pathogenic Gram-negative and Gram-positive bacteria. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Proteomic analysis of extracellular vesicles derived from Mycobacterium tuberculosis.

    Science.gov (United States)

    Lee, Jaewook; Kim, Si-Hyun; Choi, Dong-Sic; Lee, Jong Seok; Kim, Dae-Kyum; Go, Gyeongyun; Park, Seon-Min; Kim, Si Hyun; Shin, Jeong Hwan; Chang, Chulhun L; Gho, Yong Song

    2015-10-01

    The release of extracellular vesicles, also known as outer membrane vesicles, membrane vesicles, exosomes, and microvesicles, is an evolutionarily conserved phenomenon from bacteria to eukaryotes. It has been reported that Mycobacterium tuberculosis releases extracellular vesicles harboring immunologically active molecules, and these extracellular vesicles have been suggested to be applicable in vaccine development and biomarker discovery. However, the comprehensive proteomic analysis has not been performed for M. tuberculosis extracellular vesicles. In this study, we identified a total of 287 vesicular proteins by four LC-MS/MS analyses with high confidence. In addition, we identified several vesicular proteins associated with the virulence of M. tuberculosis. This comprehensive proteome profile will help elucidate the pathogenic mechanism of M. tuberculosis. The data have been deposited to the ProteomeXchange with identifier PXD001160 (http://proteomecentral.proteomexchange.org/dataset/PXD001160). © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. DNA-mediated self-assembly of artificial vesicles.

    Science.gov (United States)

    Hadorn, Maik; Eggenberger Hotz, Peter

    2010-03-26

    Although multicompartment systems made of single unilamellar vesicles offer the potential to outperform single compartment systems widely used in analytic, synthetic, and medical applications, their use has remained marginal to date. On the one hand, this can be attributed to the binary character of the majority of the current tethering protocols that impedes the implementation of real multicomponent or multifunctional systems. On the other hand, the few tethering protocols theoretically providing multicompartment systems composed of several distinct vesicle populations suffer from the readjustment of the vesicle formation procedure as well as from the loss of specificity of the linking mechanism over time. In previous studies, we presented implementations of multicompartment systems and resolved the readjustment of the vesicle formation procedure as well as the loss of specificity by using linkers consisting of biotinylated DNA single strands that were anchored to phospholipid-grafted biotinylated PEG tethers via streptavidin as a connector. The systematic analysis presented herein provides evidences for the incorporation of phospholipid-grafted biotinylated PEG tethers to the vesicle membrane during vesicle formation, providing specific anchoring sites for the streptavidin loading of the vesicle membrane. Furthermore, DNA-mediated vesicle-vesicle self-assembly was found to be sequence-dependent and to depend on the presence of monovalent salts. This study provides a solid basis for the implementation of multi-vesicle assemblies that may affect at least three distinct domains. (i) Analysis. Starting with a minimal system, the complexity of a bottom-up system is increased gradually facilitating the understanding of the components and their interaction. (ii) Synthesis. Consecutive reactions may be implemented in networks of vesicles that outperform current single compartment bioreactors in versatility and productivity. (iii) Personalized medicine. Transport and

  11. Cellular phenotype and extracellular vesicles: basic and clinical considerations.

    Science.gov (United States)

    Quesenberry, Peter J; Goldberg, Laura R; Aliotta, Jason M; Dooner, Mark S; Pereira, Mandy G; Wen, Sicheng; Camussi, Giovanni

    2014-07-01

    Early work on platelet and erythrocyte vesicles interpreted the phenomena as a discard of material from cells. Subsequently, vesicles were studied as possible vaccines and, most recently, there has been a focus on the effects of vesicles on cell fate. Recent studies have indicated that extracellular vesicles, previously referred to as microvesicles or exosomes, have the capacity to change the phenotype of neighboring cells. Extensive work has shown that vesicles derived from either the lung or liver can enter bone marrow cells (this is a prerequisite) and alter their fate toward that of the originating liver and lung tissue. Lung vesicles interacted with bone marrow cells result in the bone marrow cells expressing surfactants A-D, Clara cell protein, and aquaporin-5 mRNA. In a similar vein, liver-derived vesicles induce albumin mRNA in target marrow cells. The vesicles contain protein, mRNA, microRNA, and noncoding RNA and variably some DNA. This genetic package is delivered to cells and alters the phenotype. Further studies have shown that initially the altered phenotype is due to the transfer of mRNA and a transcriptional modulator, but long-term epigenetic changes are induced through transfer of a transcriptional factor, and the mRNA is rapidly degraded in the cell. Studies on the capacity of vesicles to restore injured tissue have been quite informative. Mesenchymal stem cell-derived vesicles are able to reverse the injury to the damaged liver and kidney. Other studies have shown that mesenchymal stem cell-derived vesicles can reverse radiation toxicity of bone marrow stem cells. Extracellular vesicles offer an intriguing strategy for treating a number of diseases characterized by tissue injury.

  12. Spin State As a Probe of Vesicle Self-Assembly

    OpenAIRE

    Kim, Sanghoon; Bellouard, Christine; Eastoe, Julian; Canilho, Nadia; Rogers, Sarah E; Ihiawakrim, Dris; Ersen, Ovidiu; Pasc, Andreea

    2016-01-01

    A novel system of paramagnetic vesicles was designed using ion pairs of iron-containing surfactants. Unilamellar vesicles (diameter ≈ 200 nm) formed spontaneously and were characterized by cryogenic transmission electron microscopy, nanoparticle tracking analysis, and light and small-angle neutron scattering. Moreover, for the first time, it is shown that magnetization measurements can be used to investigate self-assembly of such functionalized systems, giving information on the vesicle compo...

  13. Spin State As a Probe of Vesicle Self-Assembly.

    Science.gov (United States)

    Kim, Sanghoon; Bellouard, Christine; Eastoe, Julian; Canilho, Nadia; Rogers, Sarah E; Ihiawakrim, Dris; Ersen, Ovidiu; Pasc, Andreea

    2016-03-02

    A novel system of paramagnetic vesicles was designed using ion pairs of iron-containing surfactants. Unilamellar vesicles (diameter ≈ 200 nm) formed spontaneously and were characterized by cryogenic transmission electron microscopy, nanoparticle tracking analysis, and light and small-angle neutron scattering. Moreover, for the first time, it is shown that magnetization measurements can be used to investigate self-assembly of such functionalized systems, giving information on the vesicle compositions and distribution of surfactants between the bilayers and the aqueous bulk.

  14. [Seminal vesicle cystadenoma as the cause of a retrovesical tumor].

    Science.gov (United States)

    Kaminsky, A; Kania, U; Ortloff, P; Sperling, H

    2014-04-01

    Tumors of the seminal vesicle are rare. Malignant tumors are more common than benign tumors. A seminal vesicle cystadenoma is a rarity. We report on a 41-year-old man with the incidental finding of an asymptomatic retrovesical tumor. The tumor, the seminal vesicle, and the abdominal part of the ductus deferens were surgically removed. The operative access is variable and surgical treatment is the method of choice. The patient's prognosis is good and there are no signs of recurrence.

  15. Dynamic properties of the alkaline vesicle population at hippocampal synapses.

    Directory of Open Access Journals (Sweden)

    Mareike Röther

    Full Text Available In compensatory endocytosis, scission of vesicles from the plasma membrane to the cytoplasm is a prerequisite for intravesicular reacidification and accumulation of neurotransmitter molecules. Here, we provide time-resolved measurements of the dynamics of the alkaline vesicle population which appears upon endocytic retrieval. Using fast perfusion pH-cycling in live-cell microscopy, synapto-pHluorin expressing rat hippocampal neurons were electrically stimulated. We found that the relative size of the alkaline vesicle population depended significantly on the electrical stimulus size: With increasing number of action potentials the relative size of the alkaline vesicle population expanded. In contrast to that, increasing the stimulus frequency reduced the relative size of the population of alkaline vesicles. Measurement of the time constant for reacification and calculation of the time constant for endocytosis revealed that both time constants were variable with regard to the stimulus condition. Furthermore, we show that the dynamics of the alkaline vesicle population can be predicted by a simple mathematical model. In conclusion, here a novel methodical approach to analyze dynamic properties of alkaline vesicles is presented and validated as a convenient method for the detection of intracellular events. Using this method we show that the population of alkaline vesicles is highly dynamic and depends both on stimulus strength and frequency. Our results implicate that determination of the alkaline vesicle population size may provide new insights into the kinetics of endocytic retrieval.

  16. Floating Escherichia coli by expressing cyanobacterial gas vesicle genes

    Science.gov (United States)

    Wang, Tianhe; Kang, Li; Li, Jiaheng; Wu, Wenjie; Zhang, Peiran; Gong, Minghao; Lai, Weihong; Zhang, Chunyan; Chang, Lei; Peng, Yong; Yang, Zhongzhou; Li, Lian; Bao, Yingying; Xu, Haowen; Zhang, Xiaohua; Sui, Zhenghong; Yang, Guanpin; Wang, Xianghong

    2015-02-01

    Gas vesicles are hollow, air-filled polyprotein structures that provide the buoyancy to cells. They are found in a variety of prokaryotes. In this study, we isolated a partial gas vesicle protein gene cluster containing gvpA and gvpC20Ψ from Planktothrix rubescens, and inserted it into an expression vector and expressed it in E. coli. The gas vesicle was developed in bacterial cells, which made bacterial cells to float on medium surface. We also amplified gvpA and gvpC20Ψ separately and synthesized an artificial operon by fusing these two genes with the standardized gene expression controlling elements of E. coli. The artificial operon was expressed in E. coli, forming gas vesicles and floating bacteria cells. Our findings verified that the whole set of genes and the overall structure of gas vesicle gene cluster are not necessary for developing gas vesicles in bacteria cells. Two genes, gvpA and gvpC20Ψ, of the gas vesicle gene cluster are sufficient for synthesizing an artificial operon that can develop gas vesicles in bacteria cells. Our findings provided a wide range of applications including easing the harvest of cultured microalgae and bacteria, as well as enriching and remediating aquatic pollutants by constructing gas vesicles in their cells.

  17. Solubilities of sodium nitrate, sodium nitrite, and sodium aluminate in simulated nuclear waste

    Energy Technology Data Exchange (ETDEWEB)

    Reynolds, D.A.; Herting, D.L.

    1984-09-01

    Solubilities were determined for sodium nitrate, sodium nitrite, and sodium aluminate in synthetic nuclear waste liquor. Solubilities were determined as a function of temperature and solution composition (concentrations of sodium hydroxide, sodium nitrate, sodium nitrite, and sodium aluminate). Temperature had the greatest effect on the solubilities of sodium nitrate and sodium nitrite and a somewhat lesser effect on sodium aluminate solubility. Hydroxide had a great effect on the solubilities of all three salts. Other solution components had minor effects. 2 references, 8 figures, 11 tables.

  18. Novel non-systemic inhibitor of ileal apical Na+-dependent bile acid transporter reduces serum cholesterol levels in hamsters and monkeys

    NARCIS (Netherlands)

    Kitayama, K.; Nakai, D.; Kono, K.; Hoop, A.G. van der; Kurata, H.; Wit, E.C. de; Cohen, L.H.; Inaba, T.; Kohama, T.

    2006-01-01

    1-{7-[(1-(3,5-Diethoxyphenyl)-3-{[(3,5-difluorophenyl)(ethyl)amino]carbo nyl}-4-oxo-1,4-dihydroquinolin-7-yl)oxy]heptyl}-1-methylpiperidinium bromide, R-146224, is a potent, specific ileum apical sodium-dependent bile acid transporter (ASBT) inhibitor; concentrations required for 50% inhibition of

  19. The International Society for Extracellular Vesicles launches the first massive open online course on extracellular vesicles

    Science.gov (United States)

    Lässer, Cecilia; Théry, Clotilde; Buzás, Edit I.; Mathivanan, Suresh; Zhao, Weian; Gho, Yong Song; Lötvall, Jan

    2016-01-01

    The International Society for Extracellular Vesicles (ISEV) has organised its first educational online course for students and beginners in the field of extracellular vesicles (EVs). This course, “Basics of Extracellular Vesicles,” uses recorded lectures from experts in the field and will be open for an unlimited number of participants. The course is divided into 5 modules and can be accessed at www.coursera.org/learn/extracellular-vesicles. The first module is an introduction to the field covering the nomenclature and history of EVs. Module 2 focuses on the biogenesis and uptake mechanisms of EVs, as well as their RNA, protein and lipid cargo. Module 3 covers the collection and processing of cell culture media and body fluids such as blood, breast milk, cerebrospinal fluid and urine prior to isolation of EVs. Modules 4 and 5 present different isolation methods and characterisation techniques utilised in the EV field. Here, differential ultracentrifugation, size-exclusion chromatography, density gradient centrifugation, kit-based precipitation, electron microscopy, cryo-electron microscopy, flow cytometry, atomic-force microscopy and nanoparticle-tracking analysis are covered. This first massive open online course (MOOC) on EVs was launched on 15 August 2016 at the platform “Coursera” and is free of charge. PMID:27989272

  20. The International Society for Extracellular Vesicles launches the first massive open online course on extracellular vesicles.

    Science.gov (United States)

    Lässer, Cecilia; Théry, Clotilde; Buzás, Edit I; Mathivanan, Suresh; Zhao, Weian; Gho, Yong Song; Lötvall, Jan

    2016-01-01

    The International Society for Extracellular Vesicles (ISEV) has organised its first educational online course for students and beginners in the field of extracellular vesicles (EVs). This course, "Basics of Extracellular Vesicles," uses recorded lectures from experts in the field and will be open for an unlimited number of participants. The course is divided into 5 modules and can be accessed at www.coursera.org/learn/extracellular-vesicles. The first module is an introduction to the field covering the nomenclature and history of EVs. Module 2 focuses on the biogenesis and uptake mechanisms of EVs, as well as their RNA, protein and lipid cargo. Module 3 covers the collection and processing of cell culture media and body fluids such as blood, breast milk, cerebrospinal fluid and urine prior to isolation of EVs. Modules 4 and 5 present different isolation methods and characterisation techniques utilised in the EV field. Here, differential ultracentrifugation, size-exclusion chromatography, density gradient centrifugation, kit-based precipitation, electron microscopy, cryo-electron microscopy, flow cytometry, atomic-force microscopy and nanoparticle-tracking analysis are covered. This first massive open online course (MOOC) on EVs was launched on 15 August 2016 at the platform "Coursera" and is free of charge.

  1. The International Society for Extracellular Vesicles launches the first massive open online course on extracellular vesicles

    Directory of Open Access Journals (Sweden)

    Cecilia Lässer

    2016-12-01

    Full Text Available The International Society for Extracellular Vesicles (ISEV has organised its first educational online course for students and beginners in the field of extracellular vesicles (EVs. This course, “Basics of Extracellular Vesicles,” uses recorded lectures from experts in the field and will be open for an unlimited number of participants. The course is divided into 5 modules and can be accessed at www.coursera.org/learn/extracellular-vesicles. The first module is an introduction to the field covering the nomenclature and history of EVs. Module 2 focuses on the biogenesis and uptake mechanisms of EVs, as well as their RNA, protein and lipid cargo. Module 3 covers the collection and processing of cell culture media and body fluids such as blood, breast milk, cerebrospinal fluid and urine prior to isolation of EVs. Modules 4 and 5 present different isolation methods and characterisation techniques utilised in the EV field. Here, differential ultracentrifugation, size-exclusion chromatography, density gradient centrifugation, kit-based precipitation, electron microscopy, cryo-electron microscopy, flow cytometry, atomic-force microscopy and nanoparticle-tracking analysis are covered. This first massive open online course (MOOC on EVs was launched on 15 August 2016 at the platform “Coursera” and is free of charge.

  2. Role of extracellular vesicles in autoimmune diseases.

    Science.gov (United States)

    Turpin, Delphine; Truchetet, Marie-Elise; Faustin, Benjamin; Augusto, Jean-François; Contin-Bordes, Cécile; Brisson, Alain; Blanco, Patrick; Duffau, Pierre

    2016-02-01

    Extracellular vesicles (EVs) consist of exosomes released upon fusion of multivesicular bodies with the cell plasma membrane and microparticles shed directly from the cell membrane of many cell types. EVs can mediate cell-cell communication and are involved in many processes including inflammation, immune signaling, angiogenesis, stress response, senescence, proliferation, and cell differentiation. Accumulating evidence reveals that EVs act in the establishment, maintenance and modulation of autoimmune processes among several others involved in cancer and cardiovascular complications. EVs could also present biomedical applications, as disease biomarkers and therapeutic targets or agents for drug delivery. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Formation of Polyion Complex (PIC) Micelles and Vesicles with Anionic pH-Responsive Unimer Micelles and Cationic Diblock Copolymers in Water.

    Science.gov (United States)

    Ohno, Sayaka; Ishihara, Kazuhiko; Yusa, Shin-Ichi

    2016-04-26

    A random copolymer (p(A/MaU)) of sodium 2-(acrylamido)-2-methylpropanesulfonate (AMPS) and sodium 11-methacrylamidoundecanate (MaU) was prepared via conventional radical polymerization, which formed a unimer micelle under acidic conditions due to intramolecular hydrophobic interactions between the pendant undecanoic acid groups. Under basic conditions, unimer micelles were opened up to an expanded chain conformation by electrostatic repulsion between the pendant sulfonate and undecanoate anions. A cationic diblock copolymer (P163M99) consisting of poly(3-(methacrylamido)propyl)trimethylammonium chloride (PMAPTAC) and hydrophilic polybetaine, 2-(methacryloyloxy)ethylphosphorylcholine (MPC), blocks was prepared via controlled radical polymerization. Mixing of p(A/MaU) and P163M99 in 0.1 M aqueous NaCl under acidic conditions resulted in the formation of spherical polyion complex (PIC) micelles and vesicles, depending on polymer concentration before mixing. Shapes of the PIC micelles and vesicles changed under basic conditions due to collapse of the charge balance between p(A/MaU) and P163M99. The PIC vesicles can incorporate nonionic hydrophilic guest molecules, and the PIC micelles and vesicles can accept hydrophobic guest molecules in the hydrophobic core formed from p(A/MaU).

  4. Prostasome-like vesicles stimulate acrosome reaction of pig spermatozoa

    Directory of Open Access Journals (Sweden)

    Marcianò Vito

    2008-01-01

    Full Text Available Abstract Background The presence of small membranous particles characterizes the male genital fluids of different mammalian species. The influence of semen vesicles, denominated prostasomes, on sperm functional properties has been well documented in humans, but their biological activity is scarcely known in other species. The present work investigated prostasome-like vesicles in pig semen for their ability to interact with spermatozoa and to affect acrosome reaction. Methods Prostasome-like vesicles have been isolated from pig seminal plasma by high-speed centrifugation and Sephadex G-200 gel chromatography. Morphology of purified vesicles has been checked by scanning electron microscopy while their protein pattern has been investigated by SDS-PAGE. Then prostasome- like vesicles have been incubated with pig spermatozoa and their ability to interact with sperm has been tested by the aminopeptidase assay. In addition, the efficiency of vesicles to influence the acrosome reaction has been investigated by assessing the sperm acrosomal status by the PI/FITC-PNA (propidium iodide/fluorescein isothiocyanate-labeled peanut agglutinin stainings. Results Purified vesicles revealed a complex protein pattern with the occurrence of bands in the high, medium and low molecular weight range. However, the two major bands were observed at ~90 kDa and ~60 kDa. A vesicle-mediated transfer of aminopeptidase to sperm cells has been also detected. Furthermore, a significant increase of acrosome reaction extent has been revealed in spermatozoa incubated with prostasome-like vesicles in comparison to control sperm. Conclusion This is the first report demonstrating that pig prostasome-like vesicles are able, in vitro, to interact with spermatozoa and to stimulate the acrosome reaction. These findings lead to hypothesize a transfer of molecules from vesicles to sperm membrane, thus sensitizing male gametes to undergo the acrosome reaction

  5. Effect of interlamellar interactions on shear induced multilamellar vesicle formation

    Science.gov (United States)

    Kawabata, Y.; Bradbury, R.; Kugizaki, S.; Weigandt, K.; Melnichenko, Y. B.; Sadakane, K.; Yamada, N. L.; Endo, H.; Nagao, M.; Seto, H.

    2017-07-01

    Shear-induced multilamellar vesicle (MLV) formation has been studied by coupling the small-angle neutron scattering (SANS) technique with neutron spin echo (NSE) spectroscopy. A 10% mass fraction of the nonionic surfactant pentaethylene glycol dodecyl ether (C12E5) in water was selected as a model system for studying weak inter-lamellar interactions. These interactions are controlled either by adding an anionic surfactant, sodium dodecyl sulfate, or an antagonistic salt, rubidium tetraphenylborate. Increasing the charge density in the bilayer induces an enhanced ordering of the lamellar structure. The charge density dependence of the membrane bending modulus was determined by NSE and showed an increasing trend with charge. This behavior is well explained by a classical theoretical model. By considering the Caillé parameters calculated from the SANS data, the layer compressibility modulus B ¯ is estimated and the nature of the dominant inter-lamellar interaction is determined. Shear flow induces MLV formation around a shear rate of 10 s-1, when a small amount of charge is included in the membrane. The flow-induced layer undulations are in-phase between neighboring layers when the inter-lamellar interaction is sufficiently strong. Under these conditions, MLV formation can occur without significantly changing the inter-lamellar spacing. On the other hand, in the case of weak inter-lamellar interactions, the flow-induced undulations are not in-phase, and greater steric repulsion leads to an increase in the inter-lamellar spacing with shear rate. In this case, MLV formation occurs as the amplitude of the undulations gets larger and the steric interaction leads to in-phase undulations between neighboring membranes.

  6. Bioinformatics Tools for Extracellular Vesicles Research.

    Science.gov (United States)

    Keerthikumar, Shivakumar; Gangoda, Lahiru; Gho, Yong Song; Mathivanan, Suresh

    2017-01-01

    Extracellular vesicles (EVs) are a class of membranous vesicles that are released by multiple cell types into the extracellular environment. This unique class of extracellular organelles which play pivotal role in intercellular communication are conserved across prokaryotes and eukaryotes. Depending upon the cell origin and the functional state, the molecular cargo including proteins, lipids, and RNA within the EVs are modulated. Owing to this, EVs are considered as a subrepertoire of the host cell and are rich reservoirs of disease biomarkers. In addition, the availability of EVs in multiple bodily fluids including blood has created significant interest in biomarker and signaling research. With the advancement in high-throughput techniques, multiple EV studies have embarked on profiling the molecular cargo. To benefit the scientific community, existing free Web-based resources including ExoCarta, EVpedia, and Vesiclepedia catalog multiple datasets. These resources aid in elucidating molecular mechanism and pathophysiology underlying different disease conditions from which EVs are isolated. Here, the existing bioinformatics tools to perform integrated analysis to identify key functional components in the EV datasets are discussed.

  7. Insight into the template effect of vesicles on the laccase-catalyzed oligomerization of N-phenyl-1,4-phenylenediamine from Raman spectroscopy and cyclic voltammetry measurements

    Science.gov (United States)

    Ležaić, Aleksandra Janoševic; Luginbühl, Sandra; Bajuk-Bogdanović, Danica; Pašti, Igor; Kissner, Reinhard; Rakvin, Boris; Walde, Peter; Ćirić-Marjanović, Gordana

    2016-08-01

    We report about the first Raman spectroscopy study of a vesicle-assisted enzyme-catalyzed oligomerization reaction. The aniline dimer N-phenyl-1,4-phenylenediamine (= p-aminodiphenylamine, PADPA) was oxidized and oligomerized with Trametes versicolor laccase and dissolved O2 in the presence of sodium bis(2-ethylhexyl)sulfosuccinate (AOT) vesicles (80-100 nm diameter) as templates. The conversion of PADPA into oligomeric products, poly(PADPA), was monitored during the reaction by in situ Raman spectroscopy. The results obtained are compared with UV/vis/NIR and EPR measurements. All three complementary methods indicate that at least some of the poly(PADPA) products, formed in the presence of AOT vesicles, resemble the conductive emeraldine salt form of polyaniline (PANI-ES). The Raman measurements also show that structural units different from those of “ordinary” PANI-ES are present too. Without vesicles PANI-ES-like products are not obtained. For the first time, the as-prepared stable poly(PADPA)-AOT vesicle suspension was used directly to coat electrodes (without product isolation) for investigating redox activities of poly(PADPA) by cyclic voltammetry (CV). CV showed that poly(PADPA) produced with vesicles is redox active not only at pH 1.1-as expected for PANI-ES-but also at pH 6.0, unlike PANI-ES and poly(PADPA) synthesized without vesicles. This extended pH range of the redox activity of poly(PADPA) is important for applications.

  8. Leucine transport in brush border membrane vesicles from freshwater insect larvae.

    Science.gov (United States)

    Forcella, Matilde; Berra, Elisa; Giacchini, Roberto; Parenti, Paolo

    2006-11-01

    Leucine transport across brush border membrane vesicles prepared from four insect species common to European freshwater streams has been characterized. The species studied were: Ephemera danica (Ephemeroptera: Ephemeridae), Isoperla grammatica (Plecoptera: Perlodidae), Hydropsyche pellucidula (Trichoptera: Hydropsychidae), and Hybomitra bimaculata (Diptera: Tabanidae). The transport differed among the studied taxa for several features, including pH and sodium dependence, substrate affinity and specificity, and efficiency. In H. pellucidula and E. danica, leucine uptake was higher at pH 7.4 than at more alkaline or acidic pH values, whereas in I. grammatica and H. bimaculata, the uptake was rather constant when pH varied from 5.0 to 7.4, then strongly decreased at pH 8.8. All but E. danica displayed a transient intravescicular leucine accumulation in the presence of sodium, suggesting the existence of a cation-leucine symport mechanism. The sodium dependence ranged according to the following order: H. pellucidula > I. grammatica > H. bimaculata > E. danica. Moreover, in H. pellucidula and I. grammatica, the sodium-dependence was stronger at pH 8.8 than at pH 7.4. In E. danica, leucine uptake was sodium-independent at all pH values. The highest value of V(max) (45.3 pmol.s(-1).mg proteins(-1)) was in E. danica, which, however, displayed the lowest affinity (K(m) 137 muM) when compared to the kinetic parameters of other taxa. The V(max) and K(m) values were: 40 and 52.5, 32.1 and 12.5, and 4.5 and 230 for H. bimaculata, H. pellucidula, and I. grammatica, respectively. The obtained results are discussed within our current knowledge of amino acid transport systems in insects. (c) 2006 Wiley-Liss, Inc.

  9. Removal of Vesicle Structures from Transmission Electron Microscope Images

    DEFF Research Database (Denmark)

    Jensen, Katrine Hommelhoff; Sigworth, Fred; Brandt, Sami Sebastian

    2015-01-01

    symmetries of the vesicles in the polar coordinate plane. We then propose to lift the HOSVD model to a novel hierarchical model by summarizing the multidimensional HOSVD coefficients by their principal components. Along with the model, a solid vesicle normalization scheme and model selection criterion...

  10. IN-VITRO FUSION OF RETICULOCYTE ENDOCYTIC VESICLES WITH LIPOSOMES

    NARCIS (Netherlands)

    VIDAL, M; HOEKSTRA, D

    1995-01-01

    Since reticulocytes have a high demand for iron, which is required for heme biosynthesis, these cells are highly specialized in the endocytosis of the iron carrier transferrin (Tf). From the resulting endocytic vesicles (EVs), iron is released and the vesicles rapidly return to the cell membrane

  11. Generic sorting of raft lipids into secretory vesicles in yeast

    DEFF Research Database (Denmark)

    Surma, Michal A; Klose, Christian; Klemm, Robin W

    2011-01-01

    a complete lipid overview of the yeast late secretory pathway. We could show that vesicles captured with different baits carry the same cargo and have almost identical lipid compositions; being highly enriched in ergosterol and sphingolipids. This finding indicates that lipid raft sorting is a generic...... feature of vesicles carrying PM cargo and suggests a common lipid-based mechanism for their formation....

  12. Vesicle transport and photoreceptor death: fishing for molecular links.

    Science.gov (United States)

    Nagel-Wolfrum, Kerstin; Wolfrum, Uwe

    2013-06-10

    Intracellular vesicle transport defects can induce retinal degeneration and photoreceptor cell death, but the molecular connections between these processes remains poorly understood. Reporting in Developmental Cell, Nishiwaki et al. (2013) suggest that a vesicle fusion cis-SNARE complex component translates vesicular transport defects into photoreceptor cell apoptosis. Copyright © 2013 Elsevier Inc. All rights reserved.

  13. Formation and structural properties of multi-block copolymer vesicles

    Science.gov (United States)

    Wang, Rong; Ma, Shiying

    2014-03-01

    Due to the unique structure, vesicles have attracted considerable attention for their potential applications, such as gene and drug delivery, microcapsules, nanoreactors, cell membrane mimetic, synthetic organelles, etc. By using dissipative particle dynamics, we studied the self-assembly of amphiphilic multi-block copolymer. The phase diagram was constructed by varying the interaction parameters and the composition of the block copolymers. The results show that the vesicles are stable in a large region which is different from the diblock copolymer or triblock copolymer. The structural properties of vesicles can be controlled by varying the interaction parameters and the length of the hydrophobic block. The relationship between the hydrophilic and hydrophobic block length vs the aqueous cavity size and vesicle size are revealed. The copolymers with shorter hydrophobic blocks length or the higher hydrophilicity are more likely to form vesicles with larger aqueous cavity size and vesicle size as well as thinner wall thickness. However, the increase in hydrophobic-block length results to form vesicles with smaller aqueous cavity size and larger vesicle size. Acknowledgments. This work has been supported by NNSFC (No. 21074053) and NBRPC (No. 2010CB923303).

  14. Slow Sedimentation and Deformability of Charged Lipid Vesicles

    Science.gov (United States)

    Rey Suárez, Iván; Leidy, Chad; Téllez, Gabriel; Gay, Guillaume; Gonzalez-Mancera, Andres

    2013-01-01

    The study of vesicles in suspension is important to understand the complicated dynamics exhibited by cells in in vivo and in vitro. We developed a computer simulation based on the boundary-integral method to model the three dimensional gravity-driven sedimentation of charged vesicles towards a flat surface. The membrane mechanical behavior was modeled using the Helfrich Hamiltonian and near incompressibility of the membrane was enforced via a model which accounts for the thermal fluctuations of the membrane. The simulations were verified and compared to experimental data obtained using suspended vesicles labelled with a fluorescent probe, which allows visualization using fluorescence microscopy and confers the membrane with a negative surface charge. The electrostatic interaction between the vesicle and the surface was modeled using the linear Derjaguin approximation for a low ionic concentration solution. The sedimentation rate as a function of the distance of the vesicle to the surface was determined both experimentally and from the computer simulations. The gap between the vesicle and the surface, as well as the shape of the vesicle at equilibrium were also studied. It was determined that inclusion of the electrostatic interaction is fundamental to accurately predict the sedimentation rate as the vesicle approaches the surface and the size of the gap at equilibrium, we also observed that the presence of charge in the membrane increases its rigidity. PMID:23874582

  15. Lubrication synergy: Mixture of hyaluronan and dipalmitoylphosphatidylcholine (DPPC) vesicles

    DEFF Research Database (Denmark)

    Raj, Akanksha; Wang, Min; Zander, Thomas

    2017-01-01

    with the outer shell of dipalmitoylphophatidylcholine (DPPC) vesicles in bulk solution. Further, we follow adsorption to silica from mixed hyaluronan/DPPC vesicle solution by Quartz Crystal Microbalance with Dissipation measurements. Atomic Force Microscope imaging visualises the adsorbed layer structure...... and partly removed from between the surfaces under high loads. These layers offer very low friction coefficient (

  16. Block-Copolymer Vesicles as Nanoreactors for Enzymatic Reactions

    NARCIS (Netherlands)

    Chen, Qi; Schönherr, Holger; Vancso, Gyula J.

    2009-01-01

    The impact of the spatial confinement of polystyrene-block-poly(acrylic acid) (PS-b-PAA) block copolymer (BCP) vesicles on the reactivity of encapsulated bovine pancreas trypsin is studied. Enzymes, as well as small molecules, are encapsulated with loading efficiencies up to 30% in BCP vesicles with

  17. Vesiclepedia: A Compendium for Extracellular Vesicles with Continuous Community Annotation

    NARCIS (Netherlands)

    Kalra, Hina; Simpson, Richard J.; Ji, Hong; Aikawa, Elena; Altevogt, Peter; Askenase, Philip; Bond, Vincent C.; Borràs, Francesc E.; Breakefield, Xandra; Budnik, Vivian; Buzas, Edit; Camussi, Giovanni; Clayton, Aled; Cocucci, Emanuele; Falcon-Perez, Juan M.; Gabrielsson, Susanne; Gho, Yong Song; Gupta, Dwijendra; Harsha, H. C.; Hendrix, An; Hill, Andrew F.; Inal, Jameel M.; Jenster, Guido; Krämer-Albers, Eva-Maria; Lim, Sai Kiang; Llorente, Alicia; Lötvall, Jan; Marcilla, Antonio; Mincheva-Nilsson, Lucia; Nazarenko, Irina; Nieuwland, Rienk; Nolte-'t Hoen, Esther N. M.; Pandey, Akhilesh; Patel, Tushar; Piper, Melissa G.; Pluchino, Stefano; Prasad, T. S. Keshava; Rajendran, Lawrence; Raposo, Graca; Record, Michel; Reid, Gavin E.; Sánchez-Madrid, Francisco; Schiffelers, Raymond M.; Siljander, Pia; Stensballe, Allan; Stoorvogel, Willem; Taylor, Douglas; Thery, Clotilde; Valadi, Hadi; van Balkom, Bas W. M.; Vázquez, Jesús; Vidal, Michel; Wauben, Marca H. M.; Yáñez-Mó, María; Zoeller, Margot; Mathivanan, Suresh

    2012-01-01

    Extracellular vesicles (EVs) are membraneous vesicles released by a variety of cells into their microenvironment. Recent studies have elucidated the role of EVs in intercellular communication, pathogenesis, drug, vaccine and gene-vector delivery, and as possible reservoirs of biomarkers. These

  18. The freezing process of small lipid vesicles at molecular resolution

    NARCIS (Netherlands)

    Risselada, H. Jelger; Marrink, Siewert J.

    2009-01-01

    At present very little is known about the kinetic barriers which a small vesicle will face during the transformation from the liquid-crystalline to the gel phase, and what the structure of frozen vesicles looks like at the molecular level. The formation of gel domains in the strongly curved bilayer

  19. A scenario for a genetically controlled fission of artificial vesicles

    DEFF Research Database (Denmark)

    Bönzli, Eva; Hadorn, Maik; Jørgensen, Mikkel Girke

    2011-01-01

    Artificial vesicles have been used for decades as model systems of biological cells to investigate scientific questions in simulacra. In recent years, the significance of artificial vesicles further increased because they represent ideal candidates to become the building block of a de novo...... construction of a cell in a bottom-up manner. Numerous efforts to build an artificial cell that bridge the living and non-living world will most presumably represent one of the main goals of science in the 21st century. It was shown that artificial genetic programs and the required cellular machinery can...... be incorporated into vesicles, and therefore allow the synthesis of a large number of proteins (Noireaux et al. 2005). However, vesicle fission remains one of the upcoming challenges in the artificial cell project (Noireaux et al. 2011). So far, vesicle fission is implemented by applying mechanical stress...

  20. Recognition and tethering of transport vesicles at the Golgi apparatus.

    Science.gov (United States)

    Witkos, Tomasz M; Lowe, Martin

    2017-08-01

    The Golgi apparatus occupies a central position within the secretory pathway where it is a hub for vesicle trafficking. Distinct classes of transport vesicles traffic diverse cargoes into and out of this organelle, as well as between the different Golgi subcompartments. A key feature of Golgi trafficking is the specific recognition of transport vesicles at the different regions of the Golgi apparatus, required for the correct cargo delivery. Specificity is ensured by coiled-coil golgins and multi-subunit tethering complexes (MTCs), which act together to capture vesicles and promote their subsequent fusion with the Golgi membrane. In this review we discuss our current understanding of how golgins and MTCs function together to mediate the specific recognition of vesicles at the Golgi apparatus. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. ISEV position paper: extracellular vesicle RNA analysis and bioinformatics

    Directory of Open Access Journals (Sweden)

    Andrew F. Hill

    2013-12-01

    Full Text Available Extracellular vesicles (EVs are the collective term for the various vesicles that are released by cells into the extracellular space. Such vesicles include exosomes and microvesicles, which vary by their size and/or protein and genetic cargo. With the discovery that EVs contain genetic material in the form of RNA (evRNA has come the increased interest in these vesicles for their potential use as sources of disease biomarkers and potential therapeutic agents. Rapid developments in the availability of deep sequencing technologies have enabled the study of EV-related RNA in detail. In October 2012, the International Society for Extracellular Vesicles (ISEV held a workshop on “evRNA analysis and bioinformatics.” Here, we report the conclusions of one of the roundtable discussions where we discussed evRNA analysis technologies and provide some guidelines to researchers in the field to consider when performing such analysis.

  2. Membrane Protrusion Coarsening and Nanotubulation within Giant Unilamellar Vesicles

    KAUST Repository

    Węgrzyn, Ilona

    2011-11-16

    Hydrophobic side groups on a stimuli-responsive polymer, encapsulated within a single giant unilamellar vesicle, enable membrane attachment during compartment formation at elevated temperatures. We thermally modulated the vesicle through implementation of an IR laser via an optical fiber, enabling localized directed heating. Polymer-membrane interactions were monitored using confocal imaging techniques as subsequent membrane protrusions occurred and lipid nanotubes formed in response to the polymer hydrogel contraction. These nanotubes, bridging the vesicle membrane to the contracting hydrogel, were retained on the surface of the polymer compartment, where they were transformed into smaller vesicles in a process reminiscent of cellular endocytosis. This development of a synthetic vesicle system containing a stimuli-responsive polymer could lead to a new platform for studying inter/intramembrane transport through lipid nanotubes. © 2011 American Chemical Society.

  3. Extracellular vesicles as new pharmacological targets to treat atherosclerosis.

    Science.gov (United States)

    Yin, Min; Loyer, Xavier; Boulanger, Chantal M

    2015-09-15

    Extracellular vesicles released by most cell types, include apoptotic bodies (ABs), microvesicles (MVs) and exosomes. They play a crucial role in physiology and pathology, contributing to "cell-to-cell" communication by modifying the phenotype and the function of target cells. Thus, extracellular vesicles participate in the key processes of atherosclerosis from endothelial dysfunction, vascular wall inflammation to vascular remodeling. The purpose of this review is to summarize recent findings on extracellular vesicle formation, structure, release and clearance. We focus on the deleterious and beneficial effects of extracellular vesicles in the development of atherosclerosis. The potential role of extracellular vesicles as biomarkers and pharmacological targets, their innate therapeutic capacity, or their use for novel drug delivery devices in atherosclerotic cardiovascular diseases will also be discussed. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. Placental Extracellular Vesicles and Feto-Maternal Communication

    Science.gov (United States)

    Tong, M.; Chamley, L.W.

    2015-01-01

    The human placenta is an anatomically unique structure that extrudes a variety of extracellular vesicles into the maternal blood (including syncytial nuclear aggregates, microvesicles, and nanovesicles). Large quantities of extracellular vesicles are produced by the placenta in both healthy and diseased pregnancies. Since their first description more than 120 years ago, placental extracellular vesicles are only now being recognized as important carriers for proteins, lipids, and nucleic acids, which may play a crucial role in feto-maternal communication. Here, we summarize the current literature on the cargos of placental extracellular vesicles and the known effects of such vesicles on maternal cells/systems, especially those of the maternal immune and vascular systems. PMID:25635060

  5. Aceclofenac encapsulated ethanolic nano-vesicles for effective treatment of osteoarthritis

    National Research Council Canada - National Science Library

    Kaur, Arvinder; Jain, Sunil K; Pandey, Ravi S

    2012-01-01

    .... Ethanolic nano-vesicles were prepared by solvent dispersion method. Vesicles were characterized for vesicular size, surface morphology, size and size distribution, zeta potential, entrapment efficiency...

  6. Low-resolution simulations of vesicle suspensions in 2D

    Science.gov (United States)

    Kabacaoğlu, Gökberk; Quaife, Bryan; Biros, George

    2018-03-01

    Vesicle suspensions appear in many biological and industrial applications. These suspensions are characterized by rich and complex dynamics of vesicles due to their interaction with the bulk fluid, and their large deformations and nonlinear elastic properties. Many existing state-of-the-art numerical schemes can resolve such complex vesicle flows. However, even when using provably optimal algorithms, these simulations can be computationally expensive, especially for suspensions with a large number of vesicles. These high computational costs can limit the use of simulations for parameter exploration, optimization, or uncertainty quantification. One way to reduce the cost is to use low-resolution discretizations in space and time. However, it is well-known that simply reducing the resolution results in vesicle collisions, numerical instabilities, and often in erroneous results. In this paper, we investigate the effect of a number of algorithmic empirical fixes (which are commonly used by many groups) in an attempt to make low-resolution simulations more stable and more predictive. Based on our empirical studies for a number of flow configurations, we propose a scheme that attempts to integrate these fixes in a systematic way. This low-resolution scheme is an extension of our previous work [51,53]. Our low-resolution correction algorithms (LRCA) include anti-aliasing and membrane reparametrization for avoiding spurious oscillations in vesicles' membranes, adaptive time stepping and a repulsion force for handling vesicle collisions and, correction of vesicles' area and arc-length for maintaining physical vesicle shapes. We perform a systematic error analysis by comparing the low-resolution simulations of dilute and dense suspensions with their high-fidelity, fully resolved, counterparts. We observe that the LRCA enables both efficient and statistically accurate low-resolution simulations of vesicle suspensions, while it can be 10× to 100× faster.

  7. Mesenchymal stem cell-derived extracellular vesicles attenuate kidney inflammation.

    Science.gov (United States)

    Eirin, Alfonso; Zhu, Xiang-Yang; Puranik, Amrutesh S; Tang, Hui; McGurren, Kelly A; van Wijnen, Andre J; Lerman, Amir; Lerman, Lilach O

    2017-07-01

    Mesenchymal stem/stromal cells (MSCs) have distinct capability for renal repair, but may have safety concerns. MSC-derived extracellular vesicles emerged as a novel noncellular alternative. Using a porcine model of metabolic syndrome and renal artery stenosis we tested whether extracellular vesicles attenuate renal inflammation, and if this capacity is mediated by their cargo of the anti-inflammatory cytokine interleukin (IL) 10. Pigs with metabolic syndrome were studied after 16 weeks of renal artery stenosis untreated or treated four weeks earlier with a single intrarenal delivery of extracellular vesicles harvested from adipose tissue-derived autologous MSCs. Lean and sham metabolic syndrome animals served as controls (seven each). Five additional pigs with metabolic syndrome and renal artery stenosis received extracellular vesicles with pre-silenced IL10 (IL10 knock-down). Single-kidney renal blood flow, glomerular filtration rate, and oxygenation were studied in vivo and renal injury pathways ex vivo. Retention of extracellular vesicles in the stenotic kidney peaked two days after delivery and decreased thereafter. Four weeks after injection, extracellular vesicle fragments colocalized with stenotic-kidney tubular cells and macrophages, indicating internalization or fusion. Extracellular vesicle delivery attenuated renal inflammation, and improved medullary oxygenation and fibrosis. Renal blood flow and glomerular filtration rate fell in metabolic syndrome and renal artery stenosis compared to metabolic syndrome, but was restored in pigs treated with extracellular vesicles. These renoprotective effects were blunted in pigs treated with IL10-depleted extracellular vesicles. Thus, extracellular vesicle-based regenerative strategies might be useful for patients with metabolic syndrome and renal artery stenosis. Copyright © 2017 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.

  8. The launch of Journal of Extracellular Vesicles (JEV), the official journal of the International Society for Extracellular Vesicles ? about microvesicles, exosomes, ectosomes and other extracellular vesicles

    OpenAIRE

    L?tvall, Jan; Rajendran, Lawrence; Gho, Yong-Song; Thery, Clotilde; Wauben, Marca; Raposo, Graca; Sj?strand, Margareta; Taylor, Douglas; Telemo, Esbj?rn; Breakefield, Xandra O.

    2012-01-01

    In 2011, researchers around the world interested in extracellular vesicles (EV) joined forces and founded the International Society for Extracellular Vesicles (ISEV). Membership has grown to approximately 750 in eight months, and the Society’s first meeting will take place in Gothenburg, Sweden, on 18-21 April 2012. Already approximately 500 participants have been attracted to this event. These are signs of rapid expansion in global research in the field of EV.(Published: 16 April 2012)Citati...

  9. A Perspective on Extracellular Vesicles Proteomics

    Directory of Open Access Journals (Sweden)

    Livia Rosa-Fernandes

    2017-11-01

    Full Text Available Increasing attention has been given to secreted extracellular vesicles (EVs in the past decades, especially in the portrayal of their molecular cargo and role as messengers in both homeostasis and pathophysiological conditions. This review presents the state-of-the-art proteomic technologies to identify and quantify EVs proteins along with their PTMs, interacting partners and structural details. The rapid growth of mass spectrometry-based analytical strategies for protein sequencing, PTMs and structural characterization has improved the level of molecular details that can be achieved from limited amount of EVs isolated from different biological sources. Here we will provide a perspective view on the achievements and challenges on EVs proteome characterization using mass spectrometry. A detailed bioinformatics approach will help us to picture the molecular fingerprint of EVs and understand better their pathophysiological function.

  10. Versatile roles of extracellular vesicles in cancer

    Science.gov (United States)

    Kosaka, Nobuyoshi; Yoshioka, Yusuke; Fujita, Yu

    2016-01-01

    Numerous studies have shown that non–cell-autonomous regulation of cancer cells is an important aspect of tumorigenesis. Cancer cells need to communicate with stromal cells by humoral factors such as VEGF, FGFs, and Wnt in order to survive. Recently, extracellular vesicles (EVs) have also been shown to be involved in cell-cell communication between cancer cells and the surrounding microenvironment and to be important for the development of cancer. In addition, these EVs contain small noncoding RNAs, including microRNAs (miRNAs), which contribute to the malignancy of cancer cells. Here, we provide an overview of current research on EVs, especially miRNAs in EVs. We also propose strategies to treat cancers by targeting EVs around cancer cells. PMID:26974161

  11. Role of extracellular vesicles in rheumatoid arthritis.

    Science.gov (United States)

    Fu, Haitao; Hu, Die; Zhang, Licheng; Tang, Peifu

    2018-01-01

    Cell-derived extracellular vesicles (EVs) are involved in the pathogenesis of rheumatoid arthritis (RA), playing important roles in antigen presentation, inflammation, angiogenesis, cell-cell signal communication, thrombosis, and articular cartilage extracellular matrix degradation. Understanding the pathogenic mechanism of RA is important for developing therapies. The pathogenic indicators of RA, such as submicron-sized EVs, represent promising biomarkers for evaluating RA activity. This review summarizes the recent advances in understanding the pathogenesis of RA, and sheds light on the pathogenic as well as anti-inflammatory or immunosuppressive roles of EVs. We suggest that EVs could be harnessed as tools for drug delivery or targets for RA therapies. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  12. Isolation of Platelet-Derived Extracellular Vesicles.

    Science.gov (United States)

    Aatonen, Maria; Valkonen, Sami; Böing, Anita; Yuana, Yuana; Nieuwland, Rienk; Siljander, Pia

    2017-01-01

    Platelets participate in several physiological functions, including hemostasis, immunity, and development. Additionally, platelets play key roles in arterial thrombosis and cancer progression. Given this plethora of functions, there is a strong interest of the role of platelet-derived (extracellular) vesicles (PDEVs) as functional mediators and biomarkers. Moreover, the majority of the blood-borne EVs are thought to originate from either platelets or directly from the platelet precursor cells, the megakaryocytes, which reside in the bone marrow. To circumvent confusion, we use the term PDEVs for both platelet-derived and/or megakaryocyte-derived EVs. PDEVs can be isolated from blood or from isolated platelets after activation. In this chapter, we describe all commonly used PDEV isolation methods from blood and prepurified platelets.

  13. Methods to isolate extracellular vesicles for diagnosis

    Science.gov (United States)

    Kang, Hyejin; Kim, Jiyoon; Park, Jaesung

    2017-12-01

    Extracellular vesicles (EVs) are small membrane-bound bodies that are released into extracellular space by diverse cells, and are found in body fluids like blood, urine and saliva. EVs contain RNA, DNA and proteins, which can be biomarkers for diagnosis. EVs can be obtained by minimally-invasive biopsy, so they are useful in disease diagnosis. High yield and purity contribute to precise diagnosis of disease, but damaged EVs and impurities can cause confu sed results. However, EV isolation methods have different yields and purities. Furthermore, the isolation method that is most suitable to maximize EV recovery efficiency depends on the experimental conditions. This review focuses on merits and demerits of several types of EV isolation methods, and provides examples of how to diagnose disease by exploiting information obtained by analysis of EVs.

  14. A Perspective on Extracellular Vesicles Proteomics.

    Science.gov (United States)

    Rosa-Fernandes, Livia; Rocha, Victória Bombarda; Carregari, Victor Corasolla; Urbani, Andrea; Palmisano, Giuseppe

    2017-01-01

    Increasing attention has been given to secreted extracellular vesicles (EVs) in the past decades, especially in the portrayal of their molecular cargo and role as messengers in both homeostasis and pathophysiological conditions. This review presents the state-of-the-art proteomic technologies to identify and quantify EVs proteins along with their PTMs, interacting partners and structural details. The rapid growth of mass spectrometry-based analytical strategies for protein sequencing, PTMs and structural characterization has improved the level of molecular details that can be achieved from limited amount of EVs isolated from different biological sources. Here we will provide a perspective view on the achievements and challenges on EVs proteome characterization using mass spectrometry. A detailed bioinformatics approach will help us to picture the molecular fingerprint of EVs and understand better their pathophysiological function.

  15. SODIUM DEUTERIUM REACTOR

    Science.gov (United States)

    Oppenheimer, E.D.; Weisberg, R.A.

    1963-02-26

    This patent relates to a barrier system for a sodium heavy water reactor capable of insuring absolute separation of the metal and water. Relatively cold D/sub 2/O moderator and reflector is contained in a calandria into which is immersed the fuel containing tubes. The fuel elements are cooled by the sodium which flows within the tubes and surrounds the fuel elements. The fuel containing tubes are surrounded by concentric barrier tubes forming annular spaces through which pass inert gases at substantially atmospheric pressure. Header rooms above and below the calandria are provided for supplying and withdrawing the sodium and inert gases in the calandria region. (AEC)

  16. Biological reference materials for extracellular vesicle studies.

    Science.gov (United States)

    Valkonen, S; van der Pol, E; Böing, A; Yuana, Y; Yliperttula, M; Nieuwland, R; Laitinen, S; Siljander, P R M

    2017-02-15

    Extracellular vesicles (EVs) mediate normal physiological homeostasis and pathological processes by facilitating intercellular communication. Research of EVs in basic science and clinical settings requires both methodological standardization and development of reference materials (RM). Here, we show insights and results of biological RM development for EV studies. We used a three-step approach to find and develop a biological RM. First, a literature search was done to find candidates for biological RMs. Second, a questionnaire was sent to EV researchers querying the preferences for RM and their use. Third, a biological RM was selected, developed, characterized, and evaluated. The responses to the survey demonstrated a clear and recognized need for RM optimized for the calibration of EV measurements. Based on the literature, naturally occurring and produced biological RM, such as virus particles and liposomes, were proposed as RM. However, none of these candidate RMs have properties completely matching those of EVs, such as size and refractive index distribution. Therefore, we evaluated the use of nanoerythrosomes (NanoE), vesicles produced from erythrocytes, as a potential biological RM. The strength of NanoE is their resemblance to EVs. Compared to the erythrocyte-derived EVs (eryEVs), NanoE have similar morphology, a similar refractive index (1.37), larger diameter (70% of the NanoE are over 200nm), and increased positive staining for CD235a and lipids (Di-8-ANEPPS) (58% and 67% in NanoE vs. 21% and 45% in eryEVs, respectively). Altogether, our results highlight the general need to develop and validate new RM with similar physical and biochemical properties as EVs to standardize EV measurements between instruments and laboratories. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  17. Extracellular vesicles in obesity and diabetes mellitus.

    Science.gov (United States)

    Pardo, Fabián; Villalobos-Labra, Roberto; Sobrevia, Bastián; Toledo, Fernando; Sobrevia, Luis

    2017-11-24

    Cell-to-cell communication happens via diverse mechanisms including the synthesis, release and transfer to target cells of extracellular vesicles (EVs). EVs include nanovesicles (i.e., exosomes) and microvesicles, including apoptotic bodies. The amount and cargo of released EVs, which consist of microRNAs (miRNAs), mRNA, proteins, DNA, among other molecules, are altered in obesity and diabetes mellitus. EVs from these diseases show with altered cargo including several miRNAs and the enrichment with molecules involved in inflammation, immune efficiency, and cell activation. The role of EVs in obesity regards with adipocytes-released vesicles that may end in a systemic insulin resistance. In diabetes mellitus, the exosomes cargo may signal to transform a normal phenotype into a diabetic phenotype in endothelial cells. The evidence of EVs as modulators of cell function is increasing; however, it is still unclear whether exosomes or microvesicles are a trustable and useful marker for the diagnose or early detection of obesity or diabetes mellitus. In this review, we summarise the reported information regarding EVs involvement in obesity, T1 and T2 diabetes mellitus, and gestational diabetes mellitus. We emphasise the fact that studies addressing a potential effect of obesity or diabetes mellitus on cell function and the severity of the diseases are done in patients suffering simultaneously with both of these diseases, i.e., diabesity. Unfortunately, the lack of information regarding the biological effects and the potential involved mechanisms makes difficult to understand the role of the EVs as a marker of these and perhaps other diseases. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. In vitro toxicology studies of extracellular vesicles.

    Science.gov (United States)

    Maji, Sayantan; Yan, Irene K; Parasramka, Mansi; Mohankumar, Swathi; Matsuda, Akiko; Patel, Tushar

    2017-03-01

    Extracellular vesicles (EVs) are membrane-bound vesicles released from cells into the extracellular environment. There is emerging interest in the use of EVs as potential therapeutic interventions. We sought to evaluate the safety of EVs that may be therapeutically used by performing in vitro toxicological assessments. EVs were obtained from mesenchymal stem cells (MSC-EV) or from bovine milk (BM-EV) by differential ultracentrifugation, and quantitated using nanoparticle tracking analysis. Genotoxic effects, hematological effects, immunological effects and endotoxin production were evaluated at two dose levels. Neither MSC-EVs nor BM-EVs elicited detectable genotoxic effects using either the alkaline comet assay or micronucleus assay. Hemolysis was observed with BM-EVs but not with MSC-EVs. MSC-EVs did not have any significant effect on either spontaneous or collagen-induced platelet aggregation. In contrast, BM-EVs were noted to increase collagen-induced platelet aggregation, even though no spontaneous increase in platelet aggregation was noted. Both types of EVs induced leukocyte proliferation, which was greater with BM-EV. Neither MSC-EVs nor BM-EVs induced HL-60 phagocytosis, although BM-EVs decreased zymosan-induced phagocytosis. Furthermore, neither MSC-EVs nor BM-EVs induced nitric oxide production. Unlike MSC-EVs, BM-EVs tested positive for endotoxin and induced complement activation. There are significant differences in toxicological profiles between MSC-EVs and BM-EVs that may reflect variations in techniques for EV isolation, EV content or cross-species differences. The safety of MSC-EV supports their use for disease therapeutics, whereas detailed safety and toxicological assessment will be necessary before the use of BM-EVs. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  19. Polyion Complex Vesicles with Solvated Phosphobetaine Shells Formed from Oppositely Charged Diblock Copolymers

    Directory of Open Access Journals (Sweden)

    Keita Nakai

    2017-02-01

    Full Text Available Diblock copolymers consisting of a hydrophilic poly(2-(methacryloyloxyethyl phosphorylcholine (PMPC block and either a cationic or anionic block were prepared from (3-(methacrylamidopropyltrimethylammonium chloride (MAPTAC or sodium 2-(acrylamido-2-methylpropanesulfonate (AMPS. Polymers were synthesized via reversible addition-fragmentation chain transfer (RAFT radical polymerization using a PMPC macro-chain transfer agent. The degree of polymerization for PMPC, cationic PMAPTAC, and anionic PAMPS blocks was 20, 190, and 196, respectively. Combining two solutions of oppositely charged diblock copolymers, PMPC-b-PMAPTAC and PMPC-b-PAMPS, led to the spontaneous formation of polyion complex vesicles (PICsomes. The PICsomes were characterized using 1H NMR, static abd dynamic light scattering, transmittance electron microscopy (TEM, and atomic force microscopy. Maximum hydrodynamic radius (Rh for the PICsome was observed at a neutral charge balance of the cationic and anionic diblock copolymers. The Rh value and aggregation number (Nagg of PICsomes in 0.1 M NaCl was 78.0 nm and 7770, respectively. A spherical hollow vesicle structure was observed in TEM images. The hydrodynamic size of the PICsomes increased with concentration of the diblock copolymer solutions before mixing. Thus, the size of the PICsomes can be controlled by selecting an appropriate preparation method.

  20. Vesicle fusion with bilayer lipid membrane controlled by electrostatic interaction

    Directory of Open Access Journals (Sweden)

    Azusa Oshima

    2017-09-01

    Full Text Available The fusion of proteoliposomes is a promising approach for incorporating membrane proteins in artificial lipid membranes. In this study, we employed an electrostatic interaction between vesicles and supported bilayer lipid membranes (s-BLMs to control the fusion process. We combined large unilamellar vesicles (LUVs containing anionic lipids, which we used instead of proteoliposomes, and s-BLMs containing cationic lipids to control electrostatic interaction. Anionic LUVs were never adsorbed or ruptured on the SiO2 substrate with a slight negative charge, and selectively fused with cationic s-BLMs. The LUVs can be fused effectively to the target position. Furthermore, as the vesicle fusion proceeds and some of the positive charges are neutralized, the attractive interaction weakens and finally the vesicle fusion saturates. In other words, we can control the number of LUVs fused with s-BLMs by controlling the concentration of the cationic lipids in the s-BLMs. The fluidity of the s-BLMs after vesicle fusion was confirmed to be sufficiently high. This indicates that the LUVs attached to the s-BLMs were almost completely fused, and there were few intermediate state vesicles in the fusion process. We could control the position and amount of vesicle fusion with the s-BLMs by employing an electrostatic interaction.

  1. Removal of Vesicle Structures From Transmission Electron Microscope Images

    Science.gov (United States)

    Jensen, Katrine Hommelhoff; Sigworth, Fred J.; Brandt, Sami Sebastian

    2016-01-01

    In this paper, we address the problem of imaging membrane proteins for single-particle cryo-electron microscopy reconstruction of the isolated protein structure. More precisely, we propose a method for learning and removing the interfering vesicle signals from the micrograph, prior to reconstruction. In our approach, we estimate the subspace of the vesicle structures and project the micrographs onto the orthogonal complement of this subspace. We construct a 2d statistical model of the vesicle structure, based on higher order singular value decomposition (HOSVD), by considering the structural symmetries of the vesicles in the polar coordinate plane. We then propose to lift the HOSVD model to a novel hierarchical model by summarizing the multidimensional HOSVD coefficients by their principal components. Along with the model, a solid vesicle normalization scheme and model selection criterion are proposed to make a compact and general model. The results show that the vesicle structures are accurately separated from the background by the HOSVD model that is also able to adapt to the asymmetries of the vesicles. This is a promising result and suggests even wider applicability of the proposed approach in learning and removal of statistical structures. PMID:26642456

  2. [EXTRACELLULAR VESICLES: INTERCELLULAR INFORMATION FLOW AND MEDICAL APPLICATIONS].

    Science.gov (United States)

    Pupyshev, A B

    2015-01-01

    The major features of extracellular vesicles secreted by mammalian cells are considered. Cell activation caused by formation of pathology stimulates the secretion acutely. The vesicles (exosomes, microvesicles) are enriched with annexin V, tetraspanin, miRNA. Exosomes are enriched especially by integrins, heat shock proteins. Microvesicles contain elevated amounts of tissue factors, phosphatidylserine, mRNA. The vesicles carry information about the pathological process, and microvesicles contain more proteins characteristic of inflammation and death than exosomes. They are important mediators of inflammation and infection in the body, have different effects on the immune system and the processes of carcinogenesis and neurodegeneration. However, antigenic profiles of extracellular vesicles differ not profoundly in various pathologies and so far they help diagnostics limitedly. The vesicles carry signals of genetic reprogramming of the cells and epigenetic stimulation, connected with both protein factors and mRNA and miRNA. Profiles of miRNA vesicles produced by the various pathological sources are studied actively and are useful as indicators of source and stage of cancer. Some ways of therapeutic use of the vesicles are also considered.

  3. Placenta-derived extracellular vesicles: their cargo and possible functions.

    Science.gov (United States)

    Familari, Mary; Cronqvist, Tina; Masoumi, Zahra; Hansson, Stefan R

    2017-03-01

    The literature on extracellular vesicles consists of rapidly expanding and often contradictory information. In this paper we attempt to review what is currently known regarding extracellular vesicles released specifically from human placental syncytiotrophoblast cells with a focus on the common but complex pregnancy-associated syndrome pre-eclampsia, where the level of syncytiotrophoblast extracellular vesicle release is significantly increased. We review common methods for syncytiotrophoblast extracellular vesicle derivation and isolation and we discuss the cargo of syncytiotrophoblast extracellular vesicles including proteins, RNA and lipids and their possible functions. A meta-analysis of available trophoblast-derived extracellular vesicle proteomic datasets revealed only three proteins in common: albumin, fibronectin-1 and plasminogen activator inhibitor-1, suggesting some variability in vesicle cargo, most likely reflecting stage and cell type of origin. We discuss the possible sources of variability that may have led to the low number of common markers, which has led us to speculate that markers and density in common use may not be strict criteria for identifying and isolating placenta-derived exosomes.

  4. Rapid synaptic vesicle endocytosis in cone photoreceptors of salamander retina

    Science.gov (United States)

    Van Hook, Matthew J.; Thoreson, Wallace B.

    2013-01-01

    Following synaptic vesicle exocytosis, neurons retrieve the fused membrane by a process of endocytosis in order to provide a supply of vesicles for subsequent release and maintain the presynaptic active zone. Rod and cone photoreceptors use a specialized structure called the synaptic ribbon that enables them to sustain high rates of neurotransmitter release. They must also employ mechanisms of synaptic vesicle endocytosis capable of keeping up with release. While much is known about endocytosis at another retinal ribbon synapse, that of the goldfish Mb1 bipolar cell, less is known about endocytosis in photoreceptors. We used capacitance recording techniques to measure vesicle membrane fusion and retrieval in photoreceptors from salamander retinal slices. We found that application of brief depolarizing steps (endocytosis with a time constant ~250 ms. In some cases, the capacitance trace overshot the baseline, indicating excess endocytosis. Calcium had no effect on the time constant, but enhanced excess endocytosis resulting in a faster rate of membrane retrieval. Surprisingly, endocytosis was unaffected by blockers of dynamin, suggesting that cone endocytosis is dynamin-independent. This contrasts with synaptic vesicle endocytosis in rods, which was inhibited by the dynamin inhibitor dynasore and GTPγS introduced through the patch pipette, suggesting that the two photoreceptor types employ distinct pathways for vesicle retrieval. The fast kinetics of synaptic vesicle endocytosis in photoreceptors likely enables these cells to maintain a high rate of transmitter release, allowing them to faithfully signal changes in illumination to second-order neurons. PMID:23238726

  5. Tomosyn inhibits synaptic vesicle priming in Caenorhabditis elegans.

    Directory of Open Access Journals (Sweden)

    Elena O Gracheva

    2006-07-01

    Full Text Available Caenorhabditis elegans TOM-1 is orthologous to vertebrate tomosyn, a cytosolic syntaxin-binding protein implicated in the modulation of both constitutive and regulated exocytosis. To investigate how TOM-1 regulates exocytosis of synaptic vesicles in vivo, we analyzed C. elegans tom-1 mutants. Our electrophysiological analysis indicates that evoked postsynaptic responses at tom-1 mutant synapses are prolonged leading to a two-fold increase in total charge transfer. The enhanced response in tom-1 mutants is not associated with any detectable changes in postsynaptic response kinetics, neuronal outgrowth, or synaptogenesis. However, at the ultrastructural level, we observe a concomitant increase in the number of plasma membrane-contacting vesicles in tom-1 mutant synapses, a phenotype reversed by neuronal expression of TOM-1. Priming defective unc-13 mutants show a dramatic reduction in plasma membrane-contacting vesicles, suggesting these vesicles largely represent the primed vesicle pool at the C. elegans neuromuscular junction. Consistent with this conclusion, hyperosmotic responses in tom-1 mutants are enhanced, indicating the primed vesicle pool is enhanced. Furthermore, the synaptic defects of unc-13 mutants are partially suppressed in tom-1 unc-13 double mutants. These data indicate that in the intact nervous system, TOM-1 negatively regulates synaptic vesicle priming.

  6. Leukocytospermia and function of the seminal vesicles on seminal quality.

    Science.gov (United States)

    Gonzales, G F; Kortebani, G; Mazzolli, A B

    1992-05-01

    To determine possible relationships between number of leukocytes, function of seminal vesicles, and seminal quality. The study was carried out on men who consecutively attended an infertility clinic between June 1989 to June 1991. This study was conducted in a private immunological center for infertility, a tertiary care center, The Centro Immunológico-Sección Esterilidad y Reproducción. Semen samples from 280 infertility patients attending an Immunological Center for Infertility were analyzed. We evaluated the effect of leukocytospermia in the presence of normal or abnormal function of seminal vesicles on seminal quality. Sperm count, percent of motile sperm, and percent of sperm vitality were significantly reduced when both leukocytospermia and hypofunction of seminal vesicles were present (P less than 0.01). Leukocytospermic subjects with normal function of seminal vesicles showed similar seminal parameters to those nonleukocytspermics. The incidence of subjects with antisperm antibodies measured by direct immunobeads was significantly higher in leukocytospermic men with hypofunction of seminal vesicles. No differences in the incidence of antisperm antibodies with nonleukocytospermic samples were observed in those with both leukocytospermia and normal function of seminal vesicles. These data provide evidence that white blood cells were deleterious for seminal quality when seminal vesicles were also affected.

  7. Dispersion behavior and aqueous foams in mixtures of a vesicle-forming surfactant and edible nanoparticles.

    Science.gov (United States)

    Binks, Bernard P; Campbell, Shawn; Mashinchi, Saeed; Piatko, Michael P

    2015-03-17

    In an attempt to prepare ultrastable aqueous foams composed entirely of food-grade ingredients, we describe the foamability and foam stability of aqueous phases containing either calcium carbonate particles (CaCO3), sodium stearoyl lactylate surfactant (SSL), or their mixtures. Techniques including zeta potential measurements, adsorption isotherm determination, contact angles and optical and cryo-scanning electron microscopy are used to probe the interaction between particles and surfactant molecules. Aqueous dispersions of inherently hydrophilic cationic CaCO3 nanoparticles do not foam to any great extent. By contrast, aqueous dispersions of anionic SSL, which forms a lamellar phase/vesicles, foam progressively on increasing the concentration. Despite their foamability being low compared to that of micelle-forming surfactant sodium dodecyl sulfate, they are much more stable to collapse with half-lives (of up to 40 days) of around 2 orders of magnitude higher above the respective aggregation concentrations. We believe that, in addition to surfactant lamellae around bubbles, the bilayers within vesicles contain surfactant chains in a solidlike state yielding indestructible aggregates that jam the aqueous films between bubbles, reducing the drainage rate and both bubble coalescence and gas-transfer between bubbles. In mixtures of particles and surfactant, the adsorption of SSL monomers occurs on particle surfaces, leading to an increase in their hydrophobicity, promoting particle adsorption to bubble surfaces. Ultrastable foams result with half-lives of around an order of magnitude higher again at low concentrations and foams which lose only around 30% of their volume within a year at high concentrations. In the latter case, we evidence a high surface density of discrete surfactant-coated particles at bubble surfaces, rendering them stable to coalescence and disproportionation.

  8. Sodium carbonate poisoning

    Science.gov (United States)

    Sodium carbonate is found in: Automatic dishwashing soaps Clinitest (diabetes testing) tablets Glass products Pulp and paper products Some bleaches Some bubble bath solutions Some steam iron cleaners Note: This list is not all-inclusive.

  9. Docusate Sodium and Pregnancy

    Science.gov (United States)

    ... consider the benefits of treating constipation symptoms during pregnancy. Your health care provider may also want to confirm diagnosis of constipation and see how dietary and other lifestyle therapies may help. Can use of docusate sodium ...

  10. Low sodium level

    Science.gov (United States)

    ... do other vigorous activity, drink fluids such as sports drinks that contain electrolytes to keep your body's sodium level in a healthy range. Alternative Names Hyponatremia; Dilutional hyponatremia; Euvolemic hyponatremia; Hypervolemic hyponatremia; ...

  11. Characterization of transport mechanisms and determinants critical for Na+-dependent Pi symport of the PiT family paralogs human PiT1 and PiT2

    DEFF Research Database (Denmark)

    Bøttger, Pernille; Hede, Susanne E; Grunnet, Morten

    2006-01-01

    The general phosphate need in mammalian cells is accommodated by members of the P(i) transport (PiT) family (SLC20), which use either Na(+) or H(+) to mediate inorganic phosphate (P(i)) symport. The mammalian PiT paralogs PiT1 and PiT2 are Na(+)-dependent P(i) (NaP(i)) transporters...... and are exploited by a group of retroviruses for cell entry. Human PiT1 and PiT2 were characterized by expression in Xenopus laevis oocytes with (32)P(i) as a traceable P(i) source. For PiT1, the Michaelis-Menten constant for P(i) was determined as 322.5 +/- 124.5 microM. PiT2 was analyzed for the first time...... and showed positive cooperativity in P(i) uptake with a half-maximal activity constant for P(i) of 163.5 +/- 39.8 microM. PiT1- and PiT2-mediated Na(+)-dependent P(i) uptake functions were not significantly affected by acidic and alkaline pH and displayed similar Na(+) dependency patterns. However, only PiT2...

  12. Concurrent imaging of synaptic vesicle recycling and calcium dynamics.

    Directory of Open Access Journals (Sweden)

    Haiyan eLi

    2011-11-01

    Full Text Available Synaptic transmission involves the calcium-dependent release of neurotransmitter from synaptic vesicles. Genetically encoded optical probes emitting different wavelengths of fluorescent light in response to neuronal activity offer a powerful approach to understand the spatial and temporal relationship of calcium dynamics to the release of neurotransmitter in defined neuronal populations. To simultaneously image synaptic vesicle recycling and changes in cytosolic calcium, we developed a red-shifted reporter of vesicle recycling based on a vesicular glutamate transporter, VGLUT1-mOrange2 (VGLUT1-mOr2, and a presynaptically-localized green calcium indicator, synaptophysin-GCaMP3 (SyGCaMP3 with a large dynamic range. The fluorescence of VGLUT1-mOr2 is quenched by the low pH of synaptic vesicles. Exocytosis upon electrical stimulation exposes the luminal mOr2 to the neutral extracellular pH and relieves fluorescence quenching. Re-acidification of the vesicle upon endocytosis again reduces fluorescence intensity. Changes in fluorescence intensity thus monitor synaptic vesicle exo- and endocytosis, as demonstrated previously for the green VGLUT1-pHluorin. To monitor changes in calcium, we fused the synaptic vesicle protein synaptophysin to the recently improved calcium indicator GCaMP3. SyGCaMP3 is targeted to presynaptic varicosities, and exhibits changes in fluorescence in response to electrical stimulation consistent with changes in calcium concentration. Using real-time imaging of both reporters expressed in the same synapses, we determine the time course of changes in VGLUT1 recycling in relation to changes in presynaptic calcium concentration. Inhibition of P/Q- and N-type calcium channels reduces calcium levels, as well as the rate of synaptic vesicle exocytosis and the fraction of vesicles released.

  13. The puzzle of chloroplast vesicle transport – involvement of GTPases

    Directory of Open Access Journals (Sweden)

    Sazzad eKarim

    2014-09-01

    Full Text Available In the cytosol of plant cells vesicle transport occurs via secretory pathways among the endoplasmic reticulum (ER network, Golgi bodies, secretory granules, endosome and plasma membrane. Three systems transfer lipids, proteins and other important molecules through aqueous spaces to membrane-enclosed compartments, via vesicles that bud from donor membranes, being coated and uncoated before tethered and fused with acceptor membranes. In addition, molecular, biochemical and ultrastructural evidence indicates presence of a vesicle transport system in chloroplasts. Little is known about the protein components of this system. However, as chloroplasts harbour the photosynthetic apparatus that ultimately supports most organisms on the planet, close attention to their pathways is warranted. This may also reveal novel diversification and/or distinct solutions to the problems posed by the targeted intra-cellular trafficking of important molecules. To date two homologues to well-known yeast cytosolic vesicle transport proteins, CPSAR1 and CPRabA5e, have been shown to have roles in chloroplast vesicle transport, both being GTPases. Bioinformatic data indicate that several homologues of cytosolic vesicle transport system components are putatively chloroplast-localized and in addition other proteins have been implicated to participate in chloroplast vesicle transport, including vesicle-inducing protein in plastids 1 (VIPP1, thylakoid formation 1 (THF1, snowy cotyledon 2/cotyledon chloroplast biogenesis factor (SCO2/CYO1, curvature thylakoid 1 (CURT1 proteins, and a dynamin like GTPase FZO-like (FZL protein. Several putative potential cargo proteins have also been identified, including building blocks of the photosynthetic apparatus. Here we discuss details of the largely unknown putative chloroplast vesicle transport system, focusing on GTPase-related components.

  14. Dynamics of multicomponent vesicles in a viscous fluid

    Science.gov (United States)

    Sohn, Jin Sun; Tseng, Yu-Hau; Li, Shuwang; Voigt, Axel; Lowengrub, John S.

    2010-01-01

    We develop and investigate numerically a thermodynamically consistent model of two-dimensional multicomponent vesicles in an incompressible viscous fluid. The model is derived using an energy variation approach that accounts for different lipid surface phases, the excess energy (line energy) associated with surface phase domain boundaries, bending energy, spontaneous curvature, local inextensibility and fluid flow via the Stokes equations. The equations are high-order (fourth order) nonlinear and nonlocal due to incompressibil-ity of the fluid and the local inextensibility of the vesicle membrane. To solve the equations numerically, we develop a nonstiff, pseudo-spectral boundary integral method that relies on an analysis of the equations at small scales. The algorithm is closely related to that developed very recently by Veerapaneni et al. [81] for homogeneous vesicles although we use a different and more efficient time stepping algorithm and a reformulation of the inextensibility equation. We present simulations of multicomponent vesicles in an initially quiescent fluid and investigate the effect of varying the average surface concentration of an initially unstable mixture of lipid phases. The phases then redistribute and alter the morphology of the vesicle and its dynamics. When an applied shear is introduced, an initially elliptical vesicle tank-treads and attains a steady shape and surface phase distribution. A sufficiently elongated vesicle tumbles and the presence of different surface phases with different bending stiffnesses and spontaneous curvatures yields a complex evolution of the vesicle morphology as the vesicle bends in regions where the bending stiffness and spontaneous curvature are small. PMID:20808718

  15. Extracellular Vesicles in Luminal Fluid of the Ovine Uterus

    Science.gov (United States)

    Burns, Gregory; Brooks, Kelsey; Wildung, Mark; Navakanitworakul, Raphatphorn; Christenson, Lane K.; Spencer, Thomas E.

    2014-01-01

    Microvesicles and exosomes are nanoparticles released from cells and can contain small RNAs, mRNA and proteins that affect cells at distant sites. In sheep, endogenous beta retroviruses (enJSRVs) are expressed in the endometrial epithelia of the uterus and can be transferred to the conceptus trophectoderm. One potential mechanism of enJSRVs transfer from the uterus to the conceptus is via exosomes/microvesicles. Therefore, studies were conducted to evaluate exosomes in the uterine luminal fluid (ULF) of sheep. Exosomes/microvesicles (hereafter referred to as extracellular vesicles) were isolated from the ULF of day 14 cyclic and pregnant ewes using ExoQuick-TC. Transmission electron microscopy and nanoparticle tracking analysis found the isolates contained vesicles that ranged from 50 to 200 nm in diameter. The isolated extracellular vesicles were positive for two common markers of exosomes (CD63 and HSP70) by Western blot analysis. Proteins in the extracellular vesicles were determined by mass spectrometry and Western blot analysis. Extracellular vesicle RNA was analyzed for small RNAs by sequencing and enJSRVs RNA by RT-PCR. The ULF extracellular vesicles contained a large number of small RNAs and miRNAs including 81 conserved mature miRNAs. Cyclic and pregnant ULF extracellular vesicles contained enJSRVs env and gag RNAs that could be delivered to heterologous cells in vitro. These studies support the hypothesis that ULF extracellular vesicles can deliver enJSRVs RNA to the conceptus, which is important as enJSRVs regulate conceptus trophectoderm development. Importantly, these studies support the idea that extracellular vesicles containing select miRNAs, RNAs and proteins are present in the ULF and likely have a biological role in conceptus-endometrial interactions important for the establishment and maintenance of pregnancy. PMID:24614226

  16. Formation of Giant Protein Vesicles by a Lipid Cosolvent Method

    DEFF Research Database (Denmark)

    Hansen, Jesper S.; Vararattanavech, Ardcharaporn; Vissing, Thomas

    2011-01-01

    This paper describes a method to create giant protein vesicles (GPVs) of ≥10 μm by solvent‐driven fusion of large vesicles (0.1–0.2 μm) with reconstituted membrane proteins. We found that formation of GPVs proceeded from rotational mixing of protein‐reconstituted large unilamellar vesicles (LUVs)...... of spinach SoPIP2;1 and E. coli AqpZ aquaporins. Our findings show that hydrophobic interactions within the bilayer of formed GPVs are influenced not only by the solvent partitioning propensity, but also by lipid composition and membrane protein isoform....

  17. Extracellular vesicles are the Trojan horses of viral infection.

    Science.gov (United States)

    Altan-Bonnet, Nihal

    2016-08-01

    Extracellular vesicles have recently emerged as a novel mode of viral propagation exploited by both enveloped and non-enveloped viruses. In particular non-enveloped viruses utilize the hosts' production of extracellular vesicles to exit from cells non-lytically and to hide and manipulate the immune system. Moreover, challenging the long held idea that viruses behave as independent genetic units, extracellular vesicles enable multiple viral particles and genomes to collectively traffic in and out of cells, which can promote genetic cooperativity among viral quasispecies and enhance the fitness of the overall viral population. Published by Elsevier Ltd.

  18. Mating-reactive membrane vesicles from cilia of Paramecium caudatum

    Science.gov (United States)

    1976-01-01

    Membrane vesicles with a high mating reactivity were obtained from cilia of Paramecium caudatum by treatment with a solution containing 2 M urea and 0.1 mM Na2-EDTA. All processes of conjugation were induced in cells of the complementary mating type by approximately 10 mug/ml proteins of the vesicles. Electron microscope observation showed that the membrane vesicles have a diameter of 100-150 nm. Electrophoretic analysis on SDS polyacrylamide gel revealed no significant difference in polypeptide patterns of the particles from the two complementary mating types. PMID:818093

  19. Colocalization of synapsin and actin during synaptic vesicle recycling

    DEFF Research Database (Denmark)

    Bloom, Ona; Evergren, Emma; Tomilin, Nikolay

    2003-01-01

    activity, however, synapsin was detected in the pool of vesicles proximal to the active zone. In addition, actin and synapsin were found colocalized in a dynamic filamentous cytomatrix at the sites of synaptic vesicle recycling, endocytic zones. Synapsin immunolabeling was not associated with clathrin......-coated intermediates but was found on vesicles that appeared to be recycling back to the cluster. Disruption of synapsin function by microinjection of antisynapsin antibodies resulted in a prominent reduction of the cytomatrix at endocytic zones of active synapses. Our data suggest that in addition to its known...

  20. The Vesicle Priming Factor CAPS Functions as a Homodimer via C2 Domain Interactions to Promote Regulated Vesicle Exocytosis.

    Science.gov (United States)

    Petrie, Matt; Esquibel, Joseph; Kabachinski, Greg; Maciuba, Stephanie; Takahashi, Hirohide; Edwardson, J Michael; Martin, Thomas F J

    2016-09-30

    Neurotransmitters and peptide hormones are secreted by regulated vesicle exocytosis. CAPS (also known as CADPS) is a 145-kDa cytosolic and peripheral membrane protein required for vesicle docking and priming steps that precede Ca 2+ -triggered vesicle exocytosis. CAPS binds phosphatidylinositol 4,5-bisphosphate (PI(4,5)P 2 ) and SNARE proteins and is proposed to promote SNARE protein complex assembly for vesicle docking and priming. We characterized purified soluble CAPS as mainly monomer in equilibrium with small amounts of dimer. However, the active form of CAPS bound to PC12 cell membranes or to liposomes containing PI(4,5)P 2 and Q-SNARE proteins was mainly dimer. CAPS dimer formation required its C2 domain based on mutation or deletion studies. Moreover, C2 domain mutations or deletions resulted in a loss of CAPS function in regulated vesicle exocytosis, indicating that dimerization is essential for CAPS function. Comparison of the CAPS C2 domain to a structurally defined Munc13-1 C2A domain dimer revealed conserved residues involved in CAPS dimerization. We conclude that CAPS functions as a C2 domain-mediated dimer in regulated vesicle exocytosis. The unique tandem C2-PH domain of CAPS may serve as a PI(4,5)P 2 -triggered switch for dimerization. CAPS dimerization may be coupled to oligomeric SNARE complex assembly for vesicle docking and priming. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  1. Ionic control of the size of the vesicle matrix of beige mouse mast cells.

    Science.gov (United States)

    Curran, M J; Brodwick, M S

    1991-10-01

    Isolated matrices of the giant secretory vesicles of mast cells of the beige mouse were reliably produced by the osmotic lysis of isolated vesicles. These matrices maintained their form, and their sizes were easily measured using Nomarski optics. The size of the matrix depended on the ionic composition of the bathing solution. The physiologically relevant ions, histamine and serotonin, contracted the matrix. Multivalent cations condensed the matrix relative to univalents. Ag+, acid pH (below 5), and basic pH (above 9) expanded the matrix. In the presence of 10 mM histamine, lowering the pH from 9 to 5 contracted the matrix more than can be attributed to the pH-dependent matrix contraction in zero histamine. The nontitratable organic cation, dimethonium, contracts the matrix with little effect of pH in the range of 5-9. These results suggest that histamine acts as a matrix contractor in the divalent form. The dose-response (contraction) relation for histamine was gradual from micromolar to 316 mM (millimolar) histamine. Experiments with mixtures of histamine and sodium show antagonistic effects on the matrix but are inconsistent with either a model where ions compete for identical sites or a parallel model where ions interact with separate independent sites. In vigorous histamine washoff experiments, the half time for vesicle expansion in 10(-4) M pH buffer was approximately 4 s; in isotonic NaCl solution, it was 0.5 s. When 1 M histamine was presented to closely apposed matrices, fusion resulted. The matrix material returned to its initial shape after being mechanically deformed with a glass probe. These results suggest that the matrix size is controlled by its ion exchange properties. The matrix expansion can quantitatively account for the vesicular size increase observed upon exocytosis (as a postfusional event) and the osmotic nonideality of intact vesicles. The mechanical expansion is probably significant in the widening of the exocytotic pore and the dispersal

  2. Additive effects on the energy barrier for synaptic vesicle fusion cause supralinear effects on the vesicle fusion rate

    DEFF Research Database (Denmark)

    Schotten, Sebastiaan; Meijer, Marieke; Walter, Alexander Matthias

    2015-01-01

    supralinear effects on the fusion rate. To test this prediction experimentally, we developed a method to assess the number of releasable vesicles, rate constants for vesicle priming, unpriming, and fusion, and the activation energy for fusion by fitting a vesicle state model to synaptic responses induced...... by hypertonic solutions. We show that complexinI/II deficiency or phorbol ester stimulation indeed affects responses to hypertonic solution in a supralinear manner. An additive vs multiplicative relationship between activation energy and fusion rate provides a novel explanation for previously observed non...

  3. Glioblastoma extracellular vesicles: reservoirs of potential biomarkers

    Directory of Open Access Journals (Sweden)

    Redzic JS

    2014-02-01

    Full Text Available Jasmina S Redzic,1 Timothy H Ung,2 Michael W Graner2 1Skaggs School of Pharmacy and Pharmaceutical Sciences, 2Department of Neurosurgery, School of Medicine, University of Colorado Denver, Aurora, CO, USA Abstract: Glioblastoma multiforme (GBM is the most frequent and most devastating of the primary central nervous system tumors, with few patients living beyond 2 years postdiagnosis. The damage caused by the disease and our treatments for the patients often leave them physically and cognitively debilitated. Generally, GBMs appear after very short clinical histories and are discovered by imaging (using magnetic resonance imaging [MRI], and the diagnosis is validated by pathology, following surgical resection. The treatment response and diagnosis of tumor recurrence are also tracked by MRI, but there are numerous problems encountered with these monitoring modalities, such as ambiguous interpretation and forms of pseudoprogression. Diagnostic, prognostic, and predictive biomarkers would be an immense boon in following treatment schemes and in determining recurrence, which often requires an invasive intracranial biopsy to verify imaging data. Extracellular vesicles (EVs are stable, membrane-enclosed, virus-sized particles released from either the cell surface or from endosomal pathways that lead to the systemic release of EVs into accessible biofluids, such as serum/plasma, urine, cerebrospinal fluid, and saliva. EVs carry a wide variety of proteins, nucleic acids, lipids, and other metabolites, with many common features but with enough individuality to be able to identify the cell of origin of the vesicles. These components, if properly interrogated, could allow for the identification of tumor-derived EVs in biofluids, indicating tumor progression, relapse, or treatment failure. That knowledge would allow clinicians to continue with treatment regimens that were actually effective or to change course if the therapies were failing. Here, we review

  4. Visualization of peptide secretory vesicles in living nerve cells.

    Science.gov (United States)

    Park, Joshua J; Loh, Y Peng

    2011-01-01

    Analysis of real-time movements of peptidergic vesicles in live neurons provides insight into molecular mechanism(s) supporting the activity-dependent secretion of neurotrophins and neuropeptides. We examined the effect of overexpression of exogenous peptides comprising of the cytoplasmic tail sequence of vesicular carboxypeptidase E (CPE), proposed to be involved in the mechanism of trafficking of peptidergic secretory vesicles, in live hippocampal neurons. E16 rat hippocampal neurons were transfected with the peptidergic vesicle markers, CPE C-terminally tagged with red or green fluorescent protein, or brain-derived neurotrophic factor (BDNF) tagged with green fluorescent protein, and grown on dishes specialized for real-time live cell visualization. Movements of peptidergic vesicles were imaged in a temperature-controlled chamber on a confocal inverted microscope and analyzed with respect to their velocity, displacement distance, and processivity.

  5. Tension-induced fusion of bilayer membranes and vesicles

    Science.gov (United States)

    Shillcock, Julian C.; Lipowsky, Reinhard

    2005-03-01

    Maintaining the integrity of their protective plasma membrane is a primary requirement of cells. Accordingly, cellular events that breach the membrane are tightly regulated. Artificial vesicles used in drug delivery must also stay intact until they have reached the desired target. In both cases, the intrinsic resistance of the membrane to rupture must be overcome to allow the efflux of the vesicle's contents. Here, we use mesoscopic simulations to study the fusion of 28-nm-diameter vesicles to 50 × 50 nm2 planar membrane patches over 2 μs. We monitor the time evolution of 93 different fusion attempts. This allows us to construct a global morphology diagram, using the initial tensions of the vesicle and the planar membrane patch as control parameters, and to determine the corresponding fusion statistics. All successful fusion events are observed to occur within 350 ns, which reflects the presence of alternative pathways for the tension relaxation.

  6. EVpedia: a community web portal for extracellular vesicles research

    NARCIS (Netherlands)

    Kim, Dae-Kyum; Lee, Jaewook; Kim, Sae Rom; Choi, Dong-Sic; Yoon, Yae Jin; Kim, Ji Hyun; Go, Gyeongyun; Nhung, Dinh; Hong, Kahye; Jang, Su Chul; Kim, Si-Hyun; Park, Kyong-Su; Kim, Oh Youn; Park, Hyun Taek; Seo, Ji Hye; Aikawa, Elena; Baj-Krzyworzeka, Monika; van Balkom, Bas W. M.; Belting, Mattias; Blanc, Lionel; Bond, Vincent; Bongiovanni, Antonella; Borràs, Francesc E.; Buée, Luc; Buzás, Edit I.; Cheng, Lesley; Clayton, Aled; Cocucci, Emanuele; Dela Cruz, Charles S.; Desiderio, Dominic M.; Di Vizio, Dolores; Ekström, Karin; Falcon-Perez, Juan M.; Gardiner, Chris; Giebel, Bernd; Greening, David W.; Gross, Julia Christina; Gupta, Dwijendra; Hendrix, An; Hill, Andrew F.; Hill, Michelle M.; Nolte-'t Hoen, Esther; Hwang, Do Won; Inal, Jameel; Jagannadham, Medicharla V.; Jayachandran, Muthuvel; Jee, Young-Koo; Jørgensen, Malene; Kim, Kwang Pyo; Kim, Yoon-Keun; Kislinger, Thomas; Lässer, Cecilia; Lee, Dong Soo; Lee, Hakmo; van Leeuwen, Johannes; Lener, Thomas; Liu, Ming-Lin; Lötvall, Jan; Marcilla, Antonio; Mathivanan, Suresh; Möller, Andreas; Morhayim, Jess; Mullier, François; Nazarenko, Irina; Nieuwland, Rienk; Nunes, Diana N.; Pang, Ken; Park, Jaesung; Patel, Tushar; Pocsfalvi, Gabriella; del Portillo, Hernando; Putz, Ulrich; Ramirez, Marcel I.; Rodrigues, Marcio L.; Roh, Tae-Young; Royo, Felix; Sahoo, Susmita; Schiffelers, Raymond; Sharma, Shivani; Siljander, Pia; Simpson, Richard J.; Soekmadji, Carolina; Stahl, Philip; Stensballe, Allan; Stępień, Ewa; Tahara, Hidetoshi; Trummer, Arne; Valadi, Hadi; Vella, Laura J.; Wai, Sun Nyunt; Witwer, Kenneth; Yáñez-Mó, María; Youn, Hyewon; Zeidler, Reinhard; Gho, Yong Song

    2015-01-01

    Extracellular vesicles (EVs) are spherical bilayered proteolipids, harboring various bioactive molecules. Due to the complexity of the vesicular nomenclatures and components, online searches for EV-related publications and vesicular components are currently challenging. We present an improved

  7. EVpedia : a community web portal for extracellular vesicles research

    NARCIS (Netherlands)

    Kim, Dae-Kyum; Lee, Jaewook; Kim, Sae Rom; Choi, Dong-Sic; Yoon, Yae Jin; Kim, Ji Hyun; Go, Gyeongyun; Nhung, Dinh; Hong, Kahye; Jang, Su Chul; Kim, Si-Hyun; Park, Kyong-Su; Kim, Oh Youn; Park, Hyun Taek; Seo, Ji Hye; Aikawa, Elena; Baj-Krzyworzeka, Monika; van Balkom, Bas W M; Belting, Mattias; Blanc, Lionel; Bond, Vincent; Bongiovanni, Antonella; Borràs, Francesc E; Buée, Luc; Buzás, Edit I; Cheng, Lesley; Clayton, Aled; Cocucci, Emanuele; Dela Cruz, Charles S; Desiderio, Dominic M; Di Vizio, Dolores; Ekström, Karin; Falcon-Perez, Juan M; Gardiner, Chris; Giebel, Bernd; Greening, David W; Gross, Julia Christina; Gupta, Dwijendra; Hendrix, An; Hill, Andrew F; Hill, Michelle M; Nolte-'t Hoen, Esther; Hwang, Do Won; Inal, Jameel; Jagannadham, Medicharla V; Jayachandran, Muthuvel; Jee, Young-Koo; Jørgensen, Malene; Kim, Kwang Pyo; Kim, Yoon-Keun; Kislinger, Thomas; Lässer, Cecilia; Lee, Dong Soo; Lee, Hakmo; van Leeuwen, Johannes; Lener, Thomas; Liu, Ming-Lin; Lötvall, Jan; Marcilla, Antonio; Mathivanan, Suresh; Möller, Andreas; Morhayim, Jess; Mullier, François; Nazarenko, Irina; Nieuwland, Rienk; Nunes, Diana N; Pang, Ken; Park, Jaesung; Patel, Tushar; Pocsfalvi, Gabriella; Del Portillo, Hernando; Putz, Ulrich; Ramirez, Marcel I; Rodrigues, Marcio L; Roh, Tae-Young; Royo, Felix; Sahoo, Susmita; Schiffelers, Raymond|info:eu-repo/dai/nl/212909509; Sharma, Shivani; Siljander, Pia; Simpson, Richard J; Soekmadji, Carolina; Stahl, Philip; Stensballe, Allan; Stępień, Ewa; Tahara, Hidetoshi; Trummer, Arne; Valadi, Hadi; Vella, Laura J; Wai, Sun Nyunt; Witwer, Kenneth; Yáñez-Mó, María; Youn, Hyewon; Zeidler, Reinhard; Gho, Yong Song; Nolte - t Hoen, Esther|info:eu-repo/dai/nl/261632175

    2014-01-01

    MOTIVATION: Extracellular vesicles (EVs) are spherical bilayered proteolipids, harboring various bioactive molecules. Due to the complexity of the vesicular nomenclatures and components, online searches for EV-related publications and vesicular components are currently challenging. RESULTS: We

  8. Biological properties of extracellular vesicles and their physiological functions

    NARCIS (Netherlands)

    Yáñez-Mó, María; Siljander, Pia R-M; Andreu, Zoraida; Zavec, Apolonija Bedina; Borràs, Francesc E; Buzas, Edit I; Buzas, Krisztina; Casal, Enriqueta; Cappello, Francesco; Carvalho, Joana; Colás, Eva; Cordeiro-da Silva, Anabela; Fais, Stefano; Falcon-Perez, Juan M; Ghobrial, Irene M; Giebel, Bernd; Gimona, Mario; Graner, Michael; Gursel, Ihsan; Gursel, Mayda; Heegaard, Niels H H; Hendrix, An; Kierulf, Peter; Kokubun, Katsutoshi; Kosanovic, Maja; Kralj-Iglic, Veronika; Krämer-Albers, Eva-Maria; Laitinen, Saara; Lässer, Cecilia; Lener, Thomas; Ligeti, Erzsébet; Linē, Aija; Lipps, Georg; Llorente, Alicia; Lötvall, Jan; Manček-Keber, Mateja; Marcilla, Antonio; Mittelbrunn, Maria; Nazarenko, Irina; Nolte-'t Hoen, Esther N M; Nyman, Tuula A; O'Driscoll, Lorraine; Olivan, Mireia; Oliveira, Carla; Pállinger, Éva; Del Portillo, Hernando A; Reventós, Jaume; Rigau, Marina; Rohde, Eva; Sammar, Marei; Sánchez-Madrid, Francisco; Santarém, N; Schallmoser, Katharina; Ostenfeld, Marie Stampe; Stoorvogel, Willem|info:eu-repo/dai/nl/074352385; Stukelj, Roman; Van der Grein, Susanne G|info:eu-repo/dai/nl/412755211; Vasconcelos, M Helena; Wauben, Marca H M|info:eu-repo/dai/nl/112675735; De Wever, Olivier

    2015-01-01

    In the past decade, extracellular vesicles (EVs) have been recognized as potent vehicles of intercellular communication, both in prokaryotes and eukaryotes. This is due to their capacity to transfer proteins, lipids and nucleic acids, thereby influencing various physiological and pathological

  9. Theory of dielectric response of charged-bilayer-vesicle solutions

    Science.gov (United States)

    Lu, C.-Y. D.

    1996-10-01

    The dielectric response is calculated for a solution containing charged bilayer vesicles and simple electrolyte. The solution is assumed to contain a high salt concentration so that the Debye screening length is small compared to the size of the vesicles. The presence of two (electric) double layers, one on each side of the bilayer, gives low-frequency salt relaxations (kHz for 1 μm vesicles) that explain the experimentally observed α relaxations which are known to appear only for charged vesicles. The double layers also modify the high-frequency β relaxations which have been previously modeled by using the Maxwell-Wagner theory. The calculation method can be easily extended to other bilayer geometries.

  10. Biogenesis and function of Porphyromonas gingivalis outer membrane vesicles

    Science.gov (United States)

    Xie, H

    2015-01-01

    Porphyromonas gingivalis is one of the keystone pathogens associated with chronic periodontitis. All P. gingivalis strains examined thus far produce outer membrane vesicles. Recent studies have found that vesicles possess some well-known virulence factors of P. gingivalis such as adhesins, toxins and proteolytic enzymes. Carrying most of the characteristic features of their parent P. gingivalis cells, vesicles communicate with host cells and other members of microbial biofilms, resulting in the transmission of virulence factors into these host cells and the formation of pathogenic bacteria-dominated microbial communities. An in-depth understanding of both the nature and role of vesicles in the pathogenicity of P. gingivalis is both important and timely, particularly when speaking of periodontitis and its related systemic effects. PMID:26343879

  11. Yeast Membrane Vesicles: Isolation and General Characteristics1

    Science.gov (United States)

    Christensen, Michael S.; Cirillo, Vincent P.

    1972-01-01

    Yeast membrane vesicles are formed when packed yeast are ground manually in a porcelain mortar and pestle with glass beads (0.2 mm diameter). These vesicles can be separated from the other components of the grinding mixture by a combination of centrifugation steps and elution from a column of the same glass beads (0.2 mm diameter). Isolated vesicles are osmotically sensitive, contain cytoplasmic components, and have energy-independent transport function. They are unable to metabolize glucose, but have respiratory function which is thought to be associated with intravesicular mitochondria. Invertase and oligomycin-insensitive adenosine triphosphatase are present in lysed vesicle preparations, and the appropriateness of these enzyme activities as membrane markers is discussed. Images PMID:4337848

  12. Extracellular vesicles secreted by Schistosoma mansoni contain protein vaccine candidates.

    Science.gov (United States)

    Sotillo, Javier; Pearson, Mark; Potriquet, Jeremy; Becker, Luke; Pickering, Darren; Mulvenna, Jason; Loukas, Alex

    2016-01-01

    Herein we show for the first time that Schistosoma mansoni adult worms secrete exosome-like extracellular vesicles ranging from 50 to 130nm in size. Extracellular vesicles were collected from the excretory/secretory products of cultured adult flukes and purified by Optiprep density gradient, resulting in highly pure extracellular vesicle preparations as confirmed by transmission electron microscopy and Nanosight tracking analysis. Extracellular vesicle proteomic analysis showed numerous known vaccine candidates, potential virulence factors and molecules implicated in feeding. These findings provide new avenues for the exploration of host-schistosome interactions and offer a potential mechanism by which some vaccine antigens exert their protective efficacy. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  13. Large Deformation Mechanics of Plasma Membrane Chained Vesicles in Cells

    Science.gov (United States)

    Kosawada, Tadashi; Sanada, Kouichi; Takano, Tetsuo

    The clathrin-coated pits, vesicles and chained vesicles on the inner surface of the plasma membrane facilitate the cell to transport specific extracellular macromolecules. This cellular process is strongly involved with large mechanical deformations of the plasma membrane accompanied by changes in membrane curvature. The assembly of the clathrin coat is thought to provide curvature into the membrane. Hence, effects of in-plane shear elasticity due to these coat structure may be significant on the vesicular mechanics. In this study, large deformation mechanics of plasma membrane chained vesicles in cells have been formulated based on minimization of bending and in-plane shear strain energy of the membrane. Effects of outer surrounding cytoplasmic flat membrane upon mechanically stable shapes of the vesicles were revealed, while effects of in-plane shear elasticity were partly discussed.

  14. Assembly of cells and vesicles for organ engineering

    Energy Technology Data Exchange (ETDEWEB)

    Taguchi, Tetsushi, E-mail: taguchi.tetsushi@nims.go.jp [Biofunctional Materials Unit, Nano-Bio Field, Materials Nanoarchitectonics (MANA), National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan)

    2011-12-15

    The development of materials and technologies for the assembly of cells and/or vesicles is a key for the next generation of tissue engineering. Since the introduction of the tissue engineering concept in 1993, various types of scaffolds have been developed for the regeneration of connective tissues in vitro and in vivo. Cartilage, bone and skin have been successfully regenerated in vitro, and these regenerated tissues have been applied clinically. However, organs such as the liver and pancreas constitute numerous cell types, contain small amounts of extracellular matrix, and are highly vascularized. Therefore, organ engineering will require the assembly of cells and/or vesicles. In particular, adhesion between cells/vesicles will be required for regeneration of organs in vitro. This review introduces and discusses the key technologies and materials for the assembly of cells/vesicles for organ regeneration. (topical review)

  15. Sortilin mediates vascular calcification via its recruitment into extracellular vesicles

    DEFF Research Database (Denmark)

    Goettsch, Claudia; Hutscheson, JD; Aikawa, M

    2016-01-01

    Vascular calcification is a common feature of major cardiovascular diseases. Extracellular vesicles participate in the formation of microcalcifications that are implicated in atherosclerotic plaque rupture; however, the mechanisms that regulate formation of calcifying extracellular vesicles remain...... obscure. Here, we have demonstrated that sortilin is a key regulator of smooth muscle cell (SMC) calcification via its recruitment to extracellular vesicles. Sortilin localized to calcifying vessels in human and mouse atheromata and participated in formation of microcalcifications in SMC culture. Sortilin...... regulated the loading of the calcification protein tissue nonspecific alkaline phosphatase (TNAP) into extracellular vesicles, thereby conferring its calcification potential. Furthermore, SMC calcification required Rab11-dependent trafficking and FAM20C/casein kinase 2-dependent C-terminal phosphorylation...

  16. Assembly of cells and vesicles for organ engineering

    Science.gov (United States)

    Taguchi, Tetsushi

    2011-12-01

    The development of materials and technologies for the assembly of cells and/or vesicles is a key for the next generation of tissue engineering. Since the introduction of the tissue engineering concept in 1993, various types of scaffolds have been developed for the regeneration of connective tissues in vitro and in vivo. Cartilage, bone and skin have been successfully regenerated in vitro, and these regenerated tissues have been applied clinically. However, organs such as the liver and pancreas constitute numerous cell types, contain small amounts of extracellular matrix, and are highly vascularized. Therefore, organ engineering will require the assembly of cells and/or vesicles. In particular, adhesion between cells/vesicles will be required for regeneration of organs in vitro. This review introduces and discusses the key technologies and materials for the assembly of cells/vesicles for organ regeneration.

  17. Improved Methods of Producing and Administering Extracellular Vesicles | Poster

    Science.gov (United States)

    An efficient method of producing purified extracellular vesicles (EVs), in conjunction with a method that blocks liver macrophages from clearing EVs from the body, has produced promising results for the use of EVs in cancer therapy.

  18. Extracellular vesicles in human follicular fluid do not promote coagulation.

    Science.gov (United States)

    Franz, Cordula; Böing, Anita N; Montag, Markus; Strowitzki, Thomas; Markert, Udo R; Mastenbroek, Sebastiaan; Nieuwland, Rienk; Toth, Bettina

    2016-11-01

    Body fluids contain extracellular vesicles expressing tissue factor on their surface and serve as an additional trigger for coagulation. During the menstrual cycle ovarian tissue restoration is mandatory and it is unknown whether follicular fluid might provide procoagulant substances. Within an observational study, follicular fluid from women undergoing IVF/intracytoplasmic sperm injection (ICSI) was analysed by fluorescence-activated cell sorting (FACS), electron microscopy, resistive pulse sensing (RPS), nanoparticle-tracking analysis (NTA) and fibrin generation tests (FGT). The presence of extracellular vesicles, especially CD9-positive extracellular vesicles in follicular fluid, was proven. However, clotting tests revealed no procoagulant properties of the detected extracellular vesicles. Copyright © 2016 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

  19. Unilamellar Vesicle Formation and Encapsulation by Microfluidic Jetting

    National Research Council Canada - National Science Library

    Jeanne C. Stachowiak; David L. Richmond; Thomas H. Li; Allen P. Liu; Sapun H. Parekh; Daniel A. Fletcher

    2008-01-01

    ...) using a pulsed microfluidic jet. Akin to blowing a bubble, the microfluidic jet deforms a planar lipid bilayer into a vesicle that is filled with solution from the jet and separates from the planar bilayer...

  20. Interaction and rheology of vesicle suspensions in confined shear flow

    Science.gov (United States)

    Shen, Zaiyi; Farutin, Alexander; Thiébaud, Marine; Misbah, Chaouqi

    2017-10-01

    Dynamics and rheology of a confined suspension of vesicles (a model for red blood cells) are studied numerically in two dimensions by using an immersed boundary lattice Boltzmann method. We pay particular attention to the link between the spatiotemporal organization and the rheology of the suspension. Besides confinement, we analyze the effect of concentration of the suspension, ϕ (defined as the area fraction occupied by the vesicles in the simulation domain), as well as the viscosity contrast λ (defined as the ratio between the viscosity of the fluid inside the vesicles, ηint, and that of the suspending fluid, ηext). The hydrodynamic interaction between two vesicles is shown to play a key role in determining the spatial organization. For λ =1 , the pair of vesicles settles into an equilibrium state with constant interdistance, which is regulated by the confinement. The equilibrium interdistance increases with the gap between walls, following a linear relationship. However, no stable equilibrium interdistance between two tumbling vesicles is observed for λ =10 . A quite ordered suspension is observed concomitant with the existence of an equilibrium interdistance between a vesicle pair. However, a disordered suspension prevails when no pair equilibrium interdistance exists, as occurs for tumbling vesicles. We then analyze the rheology, focusing on the effective viscosity, denoted as η , as well as on normalized viscosity, defined as [η ] =(η -ηext) /(ηextϕ ) . Ordering of the suspension is accompanied by a nonmonotonic behavior of [η ] with ϕ , while η exhibits plateaus. The nonmonotonic behavior of [η ] is suppressed when a disordered pattern prevails.

  1. Cryo-electron microscopy of extracellular vesicles in fresh plasma

    OpenAIRE

    Yuana, Yuana; Koning, Roman I.; Maxim E. Kuil; Rensen, Patrick C.N.; Koster, Abraham J.; Bertina, Rogier M.; Osanto, Susanne

    2013-01-01

    Introduction: Extracellular vesicles (EV) are phospholipid bilayer-enclosed vesicles recognized as new mediators in intercellular communication and potential biomarkers of disease. They are found in many body fluids and mainly studied in fractions isolated from blood plasma in view of their potential in medicine. Due to the limitations of available analytical methods, morphological information on EV in fresh plasma is still rather limited.Objectives: To image EV and determine the morphology, ...

  2. Cystadenoma of the seminal vesicle. A case report

    DEFF Research Database (Denmark)

    Lundhus, E; Bundgaard, N; Sørensen, Flemming Brandt

    1984-01-01

    Cystadenomas of the seminal vesicle are extremely rare benign tumours, which only have been reported seven times earlier in the literature. The first Danish case is reported with discussion of symptomatology, pathology and treatment.......Cystadenomas of the seminal vesicle are extremely rare benign tumours, which only have been reported seven times earlier in the literature. The first Danish case is reported with discussion of symptomatology, pathology and treatment....

  3. Luminescent functionalized vesicles: synthesis, characterization and analytical applications

    OpenAIRE

    Balk, Stefan

    2014-01-01

    This work describes the membrane functionalization of small unilamellar phospholipid vesicles by incorporation of artificial amphiphiles. The presented investigations demonstrate a fast and simple approach for sensing molecular recognition events at the membrane-water interface. Chapter 1 describes the dynamic recognition of multivalent ligands by receptor recruiting in fluid vesicle membranes. Two amphiphilic metal-complexes with attached FRET-pair labels were prepared and embedded into D...

  4. Extracellular vesicles provide a means for tissue crosstalk during exercise

    DEFF Research Database (Denmark)

    Whitham, Martin; Parker, Benjamin L; Friedrichsen, Martin

    2018-01-01

    Exercise stimulates the release of molecules into the circulation, supporting the concept that inter-tissue signaling proteins are important mediators of adaptations to exercise. Recognizing that many circulating proteins are packaged in extracellular vesicles (EVs), we employed quantitative...... vesicles. Pulse-chase and intravital imaging experiments suggested EVs liberated by exercise have a propensity to localize in the liver and can transfer their protein cargo. Moreover, by employing arteriovenous balance studies across the contracting human limb, we identified several novel candidate...

  5. TNF-? promotes extracellular vesicle release in mouse astrocytes through glutaminase

    OpenAIRE

    Wang, Kaizhe; Ye, Ling; Lu, Hongfang; Chen, Huili; Zhang, Yanyan; Huang, Yunlong; Zheng, Jialin C.

    2017-01-01

    Background Extracellular vesicles (EVs) are membrane-contained vesicles shed from cells. EVs contain proteins, lipids, and nucleotides, all of which play important roles in intercellular communication. The release of EVs is known to increase during neuroinflammation. Glutaminase, a mitochondrial enzyme that converts glutamine to glutamate, has been implicated in the biogenesis of EVs. We have previously demonstrated that TNF-? promotes glutaminase expression in neurons. However, the expressio...

  6. Adsorption and encapsulation of flexible polyelectrolytes in charged spherical vesicles

    Science.gov (United States)

    Shojaei, H. R.; Muthukumar, M.

    2017-06-01

    We present a theory of adsorption of flexible polyelectrolytes on the interior and exterior surfaces of a charged vesicle in an electrolyte solution. The criteria for adsorption and the density profiles of the adsorbed polymer chain are derived in terms of various characteristics of the polymer, vesicle, and medium, such as the charge density and length of the polymer, charge density and size of the vesicle, electrolyte concentration and dielectric constant of the medium. For adsorption inside the vesicle, the competition between the loss of conformational entropy and gain in adsorption energy results in two kinds of encapsulated states, depending on the strength of the polymer-vesicle interaction. By considering also the adsorption from outside the vesicle, we derive the entropic and energy contributions to the free energy change to transfer an adsorbed chain in the interior to an adsorbed chain on the exterior. In this paper, we have used the Wentzel-Kramers-Brillouin (WKB) method to solve the equation for the probability distribution function of the chain. The present WKB results are compared with the previous results based on variational methods. The WKB and variational results are in good agreement for both the interior and exterior states of adsorption, except in the zero-salt limit for adsorption in the exterior region. The adsorption criteria and density profiles for both the interior and exterior states are presented in terms of various experimentally controllable variables. Calculation of the dependencies of free energy change to transfer an adsorbed chain from the interior to the exterior surface on salt concentration and vesicle radius shows that the free energy penalty to expel a chain from a vesicle is only of the order of thermal energy.

  7. Development of sodium technology

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Sung Tai; Nam, H. Y.; Choi, Y. D. [and others

    2000-05-01

    The objective of present study is to produce the experimental data for development and verification of computer codes for development of LMR and to develop the preliminary technologies for the future large scale verification experiments. A MHD experimental test loop has been constructed for the quantitative analysis of the effect of magnetic field on the sodium flow and experiments are carried out for three EM pumps. The previous pressure drop correlations are evaluated using the experimental data obtained from the pressure drop experiment in a 19-pin fuel assembly with wire spacer. An dimensionless variable is proposed to describe the amplitude and frequency of the fluctuation of free surface using the experimental data obtained from free surface experimental apparatus and an empirical correlation is developed using this dimensionless variable. An experimental test loop is constructed to measure the flow characteristics in IHX shell side and the local pressure drop in fuel assembly, and to test the vibration behaviour of fuel pins due to flow induced vibration. The sodium two-phase flow measuring technique using the electromagnetic flowmeter is developed and the sodium differential pressure drop measuring technique using the method of direct contact of sodium and oil is established. The work on the analysis of sodium fire characteristics and produce data for vlidation of computer code is performed. Perfect reopen time of self plugged leak path was observed to be about 130 minutes after water leak initiation. Reopen shape of a specimen appeared to be double layer of circular type, and reopen size of this specimen surface was about 2mm diameter on sodium side. In small water leakage experiments, the following correlation equation about the reopen time between sodium temperature and initial leak rate was obtained, {tau}{sub c} = {delta}{center_dot}g{sup -0.83}{center_dot}10{sup (3570/T{sub Na}-3.34)}, in 400-500 deg C of liquid sodium atmosphere. The characteristics

  8. Inherited sodium avid states.

    Science.gov (United States)

    Achard, Jean-Michel; Hadchouel, Juliette; Faure, Sébastien; Jeunemaitre, Xavier

    2006-04-01

    Several familial forms of hypertension have been identified, in which the mendelian pattern of inheritance indicated that hypertension results from the alteration of a single gene. This short review focuses on those rare monogenic disorders characterized by a low-renin profile. This common feature reflects that the causative mutations responsible for these disorders all result in an excessive sodium reabsorption in the aldosterone-dependent nephron. Low-renin familial hypertensions with hypokalemia encompass familial hyperaldosteronisms, in which aldosterone levels are elevated, and familial pseudohyperaldosteronisms, mimicking aldosteronism despite appropriately suppressed aldosterone levels. In these disorders, the avidity of the kidney for sodium is because of dysregulated sodium reabsorption through the epithelial sodium channel ENaC and results in potassium wasting and metabolic alcalosis. Familial hypertension with hyperkalemia is a specific syndrome resulting from mutations in at least 3 different genes, among which 2 have been recently identified. These genes encode members of a new family of kinase, the WNK kinases, involved in the regulation of sodium and potassium excretion by the kidney.

  9. Melanoma affects the composition of blood cell-derived extracellular vesicles

    OpenAIRE

    Nina Koliha; Ute Heider; Tobias Ozimkowski; Martin Wiemann; Andreas Bosio; Stefan Wild

    2016-01-01

    Extracellular vesicles are specifically loaded with nucleic acids, lipids, and proteins from their parental cell. Therefore, the constitution of extracellular vesicles reflects the type and status of the originating cell and extracellular vesicles in melanoma patient’s plasma could be indicative for the tumor. Likewise, extracellular vesicles might influence tumor progression by regulating immune responses. We performed a broad protein characterization of extracellular vesicles from plasma of...

  10. Lipid Vesicle Shape Analysis from Populations Using Light Video Microscopy and Computer Vision

    OpenAIRE

    Jernej Zupanc; Barbara Drašler; Sabina Boljte; Veronika Kralj-Iglič; Aleš Iglič; Deniz Erdogmus; Damjana Drobne

    2014-01-01

    We present a method for giant lipid vesicle shape analysis that combines manually guided large-scale video microscopy and computer vision algorithms to enable analyzing vesicle populations. The method retains the benefits of light microscopy and enables non-destructive analysis of vesicles from suspensions containing up to several thousands of lipid vesicles (1-50 µm in diameter). For each sample, image analysis was employed to extract data on vesicle quantity and size distributions of their ...

  11. Extracellular Vesicles and Autophagy in Osteoarthritis

    Directory of Open Access Journals (Sweden)

    Tianyang Gao

    2016-01-01

    Full Text Available Osteoarthritis (OA is a type of chronic joint disease that is characterized by the degeneration and loss of articular cartilage and hyperplasia of the synovium and subchondral bone. There is reasonable knowledge about articular cartilage physiology, biochemistry, and chondrocyte metabolism. However, the etiology and pathogenesis of OA remain unclear and need urgent clarification to guide the early diagnosis and treatment of OA. Extracellular vesicles (EVs are small membrane-linking particles that are released from cells. In recent decades, several special biological properties have been found in EV, especially in terms of cartilage. Autophagy plays a critical role in the regulation of cellular homeostasis. Likewise, more and more research has gradually focused on the effect of autophagy on chondrocyte proliferation and function in OA. The synthesis and release of EV are closely associated with autophagy. At the same time, both EV and autophagy play a role in OA development. Based on the mechanism of EV and autophagy in OA development, EV may be beneficial in the early diagnosis of OA; on the other hand, the combination of EV and autophagy-related regulatory drugs may provide insight into possible OA therapeutic strategies.

  12. Dysregulations of Synaptic Vesicle Trafficking in Schizophrenia.

    Science.gov (United States)

    Egbujo, Chijioke N; Sinclair, Duncan; Hahn, Chang-Gyu

    2016-08-01

    Schizophrenia is a serious psychiatric illness which is experienced by about 1 % of individuals worldwide and has a debilitating impact on perception, cognition, and social function. Over the years, several models/hypotheses have been developed which link schizophrenia to dysregulations of the dopamine, glutamate, and serotonin receptor pathways. An important segment of these pathways that have been extensively studied for the pathophysiology of schizophrenia is the presynaptic neurotransmitter release mechanism. This set of molecular events is an evolutionarily well-conserved process that involves vesicle recruitment, docking, membrane fusion, and recycling, leading to efficient neurotransmitter delivery at the synapse. Accumulated evidence indicate dysregulation of this mechanism impacting postsynaptic signal transduction via different neurotransmitters in key brain regions implicated in schizophrenia. In recent years, after ground-breaking work that elucidated the operations of this mechanism, research efforts have focused on the alterations in the messenger RNA (mRNA) and protein expression of presynaptic neurotransmitter release molecules in schizophrenia and other neuropsychiatric conditions. In this review article, we present recent evidence from schizophrenia human postmortem studies that key proteins involved in the presynaptic release mechanism are dysregulated in the disorder. We also discuss the potential impact of dysfunctional presynaptic neurotransmitter release on the various neurotransmitter systems implicated in schizophrenia.

  13. Extracellular Vesicles and Autophagy in Osteoarthritis

    Science.gov (United States)

    Guo, Weimin; Chen, Mingxue; Huang, Jingxiang; Yuan, Zhiguo; Zhang, Yu; Wang, Mingjie; Li, Penghao; Wang, Aiyuan; Wang, Yu; Sui, Xiang; Zhang, Li; Xu, Wenjing; Lu, Shibi

    2016-01-01

    Osteoarthritis (OA) is a type of chronic joint disease that is characterized by the degeneration and loss of articular cartilage and hyperplasia of the synovium and subchondral bone. There is reasonable knowledge about articular cartilage physiology, biochemistry, and chondrocyte metabolism. However, the etiology and pathogenesis of OA remain unclear and need urgent clarification to guide the early diagnosis and treatment of OA. Extracellular vesicles (EVs) are small membrane-linking particles that are released from cells. In recent decades, several special biological properties have been found in EV, especially in terms of cartilage. Autophagy plays a critical role in the regulation of cellular homeostasis. Likewise, more and more research has gradually focused on the effect of autophagy on chondrocyte proliferation and function in OA. The synthesis and release of EV are closely associated with autophagy. At the same time, both EV and autophagy play a role in OA development. Based on the mechanism of EV and autophagy in OA development, EV may be beneficial in the early diagnosis of OA; on the other hand, the combination of EV and autophagy-related regulatory drugs may provide insight into possible OA therapeutic strategies. PMID:28078284

  14. Towards traceable size determination of extracellular vesicles

    Directory of Open Access Journals (Sweden)

    Zoltán Varga

    2014-02-01

    Full Text Available Background: Extracellular vesicles (EVs have clinical importance due to their roles in a wide range of biological processes. The detection and characterization of EVs are challenging because of their small size, low refractive index, and heterogeneity. Methods: In this manuscript, the size distribution of an erythrocyte-derived EV sample is determined using state-of-the-art techniques such as nanoparticle tracking analysis, resistive pulse sensing, and electron microscopy, and novel techniques in the field, such as small-angle X-ray scattering (SAXS and size exclusion chromatography coupled with dynamic light scattering detection. Results: The mode values of the size distributions of the studied erythrocyte EVs reported by the different methods show only small deviations around 130 nm, but there are differences in the widths of the size distributions. Conclusion: SAXS is a promising technique with respect to traceability, as this technique was already applied for traceable size determination of solid nanoparticles in suspension. To reach the traceable measurement of EVs, monodisperse and highly concentrated samples are required.

  15. Formulation and optimization of nano-sized ethosomes for enhanced transdermal delivery of cromolyn sodium.

    Science.gov (United States)

    Rakesh, R; Anoop, K R

    2012-10-01

    The current study was aimed to investigate the feasibility of transdermal delivery of cromolyn sodium using a novel lipid vesicular carrier, ethosomes. Ethosomes of cromolyn sodium was prepared, optimized, and characterized for vesicle shape, vesicle size and size distribution, zeta potential, entrapment efficiency, in vitro drug release, in vitro skin permeation, in vitro skin deposition and vesicle stability. Histological examination of porcine ear skin treated with optimized ethosomal formulation was performed to study the change of skin morphologies. The optimized cromolyn sodium ethosomes showed reasonable entrapment efficiency (49.88±1.84%), optimum nanometric size range (133.8 ± 7.5 nm), and high zeta potential (-69.82 ± 1.2 mV). In vitro drug release studies of optimized ethosomal formulation through cellophane membrane showed an enhanced and sustained delivery of drug compared to conventional liposomes, hydroethanolic, (45% v/v) and phosphate buffer saline PBS pH 7.4 drug solutions. The optimized ethosomal formulation showed significantly-enhanced transdermal flux (18.49 ± 0.08 mg/cm(2)/h) across porcine ear skin as compared to liposome (1.80 ± 0.12 mg/cm(2)/h), hydroethanolic drug solution (4.45 ± 0.71 mg/cm(2)/h), and PBS pH 7.4 drug solution (1.18 ± 0.35 mg/cm(2)/h). Moreover, ethosomal formulation showed better skin drug deposition (10.28 ± 0.67%) and shortest lag time (0.11 ± 0.09 h) for cromolyn sodium. Our significant results suggest that ethosomes can be a promising tool for transdermal delivery of cromolyn sodium.

  16. Formulation and optimization of nano-sized ethosomes for enhanced transdermal delivery of cromolyn sodium

    Directory of Open Access Journals (Sweden)

    R Rakesh

    2012-01-01

    Full Text Available Aim: The current study was aimed to investigate the feasibility of transdermal delivery of cromolyn sodium using a novel lipid vesicular carrier, ethosomes. Materials And Methods: Ethosomes of cromolyn sodium was prepared, optimized, and characterized for vesicle shape, vesicle size and size distribution, zeta potential, entrapment efficiency, in vitro drug release, in vitro skin permeation, in vitro skin deposition and vesicle stability. Histological examination of porcine ear skin treated with optimized ethosomal formulation was performed to study the change of skin morphologies. Results: The optimized cromolyn sodium ethosomes showed reasonable entrapment efficiency (49.88±1.84%, optimum nanometric size range (133.8 ± 7.5 nm, and high zeta potential (-69.82 ± 1.2 mV. In vitro drug release studies of optimized ethosomal formulation through cellophane membrane showed an enhanced and sustained delivery of drug compared to conventional liposomes, hydroethanolic, (45% v/v and phosphate buffer saline PBS pH 7.4 drug solutions. The optimized ethosomal formulation showed significantly-enhanced transdermal flux (18.49 ± 0.08 mg/cm 2 /h across porcine ear skin as compared to liposome (1.80 ± 0.12 mg/cm 2 /h, hydroethanolic drug solution (4.45 ± 0.71 mg/cm 2 /h, and PBS pH 7.4 drug solution (1.18 ± 0.35 mg/cm 2 /h. Moreover, ethosomal formulation showed better skin drug deposition (10.28 ± 0.67% and shortest lag time (0.11 ± 0.09 h for cromolyn sodium. Conclusion: Our significant results suggest that ethosomes can be a promising tool for transdermal delivery of cromolyn sodium.

  17. Measuring Synaptic Vesicle Endocytosis in Cultured Hippocampal Neurons.

    Science.gov (United States)

    Villarreal, Seth; Lee, Sung Hoon; Wu, Ling-Gang

    2017-09-04

    During endocytosis, fused synaptic vesicles are retrieved at nerve terminals, allowing for vesicle recycling and thus the maintenance of synaptic transmission during repetitive nerve firing. Impaired endocytosis in pathological conditions leads to decreases in synaptic strength and brain functions. Here, we describe methods used to measure synaptic vesicle endocytosis at the mammalian hippocampal synapse in neuronal culture. We monitored synaptic vesicle protein endocytosis by fusing a synaptic vesicular membrane protein, including synaptophysin and VAMP2/synaptobrevin, at the vesicular lumenal side, with pHluorin, a pH-sensitive green fluorescent protein that increases its fluorescence intensity as the pH increases. During exocytosis, vesicular lumen pH increases, whereas during endocytosis vesicular lumen pH is re-acidified. Thus, an increase of pHluorin fluorescence intensity indicates fusion, whereas a decrease indicates endocytosis of the labelled synaptic vesicle protein. In addition to using the pHluorin imaging method to record endocytosis, we monitored vesicular membrane endocytosis by electron microscopy (EM) measurements of Horseradish peroxidase (HRP) uptake by vesicles. Finally, we monitored the formation of nerve terminal membrane pits at various times after high potassium-induced depolarization. The time course of HRP uptake and membrane pit formation indicates the time course of endocytosis.

  18. Asymmetric osmotic water permeation through a vesicle membrane

    Science.gov (United States)

    Su, Jiaye; Zhao, Yunzhen; Fang, Chang; Shi, Yue

    2017-05-01

    Understanding the water permeation through a cell membrane is of primary importance for biological activities and a key step to capture its shape transformation in salt solution. In this work, we reveal the dynamical behaviors of osmotically driven transport of water molecules across a vesicle membrane by molecular dynamics simulations. Of particular interest is that the water transport in and out of vesicles is highly distinguishable given the osmotic force are the same, suggesting an asymmetric osmotic transportation. This asymmetric phenomenon exists in a broad range of parameter space such as the salt concentration, temperature, and vesicle size and can be ascribed to the similar asymmetric potential energy of lipid-ion, lipid-water, lipid-solution, lipid-lipid, and the lipid-lipid energy fluctuation. Specifically, the water flux has a linear increase with the salt concentration, similar to the prediction by Nernst-Planck equation or Fick's first law. Furthermore, due to the Arrhenius relation between the membrane permeability and temperature, the water flux also exhibits excellent Arrhenius dependence on the temperature. Meanwhile, the water flux shows a linear increase with the vesicle surface area since the flux amount across a unit membrane area should be a constant. Finally, we also present the anonymous diffusion behaviors for the vesicle itself, where transitions from normal diffusion at short times to subdiffusion at long times are identified. Our results provide significant new physical insights for the osmotic water permeation through a vesicle membrane and are helpful for future experimental studies.

  19. Active elastohydrodynamics of vesicles in narrow blind constrictions

    Science.gov (United States)

    Fai, T. G.; Kusters, R.; Harting, J.; Rycroft, C. H.; Mahadevan, L.

    2017-11-01

    Fluid-resistance limited transport of vesicles through narrow constrictions is a recurring theme in many biological and engineering applications. Inspired by the motor-driven movement of soft membrane-bound vesicles into closed neuronal dendritic spines, here we study this problem using a combination of passive three-dimensional simulations and a simplified semianalytical theory for the active transport of vesicles forced through constrictions by molecular motors. We show that the motion of these objects is characterized by two dimensionless quantities related to the geometry and to the strength of forcing relative to the vesicle elasticity. We use numerical simulations to characterize the transit time for a vesicle forced by fluid pressure through a constriction in a channel and find that relative to an open channel, transport into a blind end leads to the formation of a smaller forward-flowing lubrication layer that strongly impedes motion. When the fluid pressure forcing is complemented by forces due to molecular motors that are responsible for vesicle trafficking into dendritic spines, we find that the competition between motor forcing and fluid drag results in multistable dynamics reminiscent of the real system. Our study highlights the role of nonlocal hydrodynamic effects in determining the kinetics of vesicular transport in constricted geometries.

  20. Formation of asymmetric vesicles via phospholipase D-mediated transphosphatidylation.

    Science.gov (United States)

    Takaoka, Rina; Kurosaki, Haruko; Nakao, Hiroyuki; Ikeda, Keisuke; Nakano, Minoru

    2018-02-01

    Most biomembranes have an asymmetric structure with regard to phospholipid distribution between the inner and outer leaflets of the lipid bilayers. Control of the asymmetric distribution plays a pivotal role in several cellular functions such as intracellular membrane fusion and cell division. The mechanism by which membrane asymmetry and its alteration function in these transformation processes is not yet clear. To understand the significance of membrane asymmetry on trafficking and metabolism of intracellular vesicular components, a system that experimentally reproduces the asymmetric nature of biomembranes is essential. Here, we succeeded in obtaining asymmetric vesicles by means of transphosphatidylation reactions with phospholipase D (PLD), which acts exclusively on phosphatidylcholine (PC) present in the outer leaflet of vesicles. By treating PC vesicles with PLD in the presence of 1.7M serine and 0.3M ethanolamine, we obtained asymmetric vesicles that are topologically similar to intracellular vesicles containing phosphatidylserine and phosphatidylethanolamine in the cytosolic leaflet. PLD and other unwanted compounds could be removed by trypsin digestion followed by dialysis. Our established technique has a great advantage over conventional methods in that asymmetric vesicles can be provided at high yield and high efficiency, which is requisite for most physicochemical assays. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Extracellular Membrane Vesicles and Phytopathogenicity of Acholeplasma laidlawii PG8

    Directory of Open Access Journals (Sweden)

    Vladislav M. Chernov

    2012-01-01

    Full Text Available For the first time, the phytopathogenicity of extracellular vesicles of Acholeplasma laidlawii PG8 (a ubiquitous mycoplasma that is one of the five common species of cell culture contaminants and is a causative agent for phytomycoplasmoses in Oryza sativa L. plants was studied. Data on the ability of extracellular vesicles of Acholeplasma laidlawii PG8 to penetrate from the nutrient medium into overground parts of Oryza sativa L. through the root system and to cause alterations in ultrastructural organization of the plants were presented. As a result of the analysis of ultrathin leaf sections of plants grown in medium with A. laidlawii PG8 vesicles, we detected significant changes in tissue ultrastructure characteristic to oxidative stress in plants as well as their cultivation along with bacterial cells. The presence of nucleotide sequences of some mycoplasma genes within extracellular vesicles of Acholeplasma laidlawii PG8 allowed a possibility to use PCR (with the following sequencing to perform differential detection of cells and bacterial vesicles in samples under study. The obtained data may suggest the ability of extracellular vesicles of the mycoplasma to display in plants the features of infection from the viewpoint of virulence criteria—invasivity, infectivity—and toxigenicity—and to favor to bacterial phytopathogenicity.

  2. Biogenesis and function of ESCRT-dependent extracellular vesicles.

    Science.gov (United States)

    Juan, Thomas; Fürthauer, Maximilian

    2018-02-01

    From bacteria to humans, cells secrete a large variety of membrane-bound extracellular vesicles. Only relatively recently has it however started to become clear that the exovesicular transport of proteins and RNAs is important for normal physiology and numerous pathological conditions. Extracellular vesicles can be formed through the release of the intralumenal vesicles of multivesicular endosomes as so-called exosomes, or through direct, ectosomal, budding from the cell surface. Through their ability to promote the bending of membranes away from the cytoplasm, the components of the Endosomal Sorting Complex Required for Transport (ESCRT) have been implicated in both exo- and ectosomal biogenesis. Studies of the ESCRT machinery may therefore provide important insights into the formation and function of extracellular vesicles. In the present review, we first describe the cell biological mechanisms through which ESCRT components contribute to the biogenesis of different types of extracellular vesicles. We then discuss how recent functional studies have started to uncover important roles of ESCRT-dependent extracellular vesicles in a wide variety of processes, including the transport of developmental signaling molecules and embryonic morphogenesis, the regulation of social behavior and host-pathogen interactions, as well as the etiology and progression of neurodegenerative pathologies and cancer. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Endothelial plasmalemmal vesicles have a characteristic striped bipolar surface structure.

    Science.gov (United States)

    Peters, K R; Carley, W W; Palade, G E

    1985-12-01

    Capillary endothelial cells have a large population of small (65-80 nm diameter in transmission electron microscopy) vesicles of which a large fraction is associated with the plasmalemma of the luminal and abluminal side. We studied the fine structure and distribution of these plasmalemmal vesicles by high resolution scanning electron microscopy in cultured endothelial cells obtained from bovine adrenal cortical capillaries. Cell monolayers were covered with polylysine-coated silicon chips, split in high potassium buffer, fixed in aldehyde mixtures, and then treated with OsO4 and thiocarbohydrazide. After critical point drying, the specimens were coated with a thin (less than 2 nm) continuous film of chromium. On the cytoplasmic aspect of the dorsal plasmalemmal fragments seen in such specimens, plasmalemmal vesicles appear as uniform vesicular protrusions approximately 70-90 nm in diameter, preferentially concentrated in distinct large fields in which they occur primarily as single units. Individual plasmalemmal vesicles exhibit a striped surface fine structure which consists of ridges approximately 10 nm in diameter, separated by furrows and oriented as meridians, often ending at two poles on opposite sides of the vesicles in a plane parallel to the plasmalemma. This striped surface structure is clearly distinct from the cage structure of coated pits found, at low surface density, on the same specimens. The cytoplasmic aspect of the plasmalemma proper is covered by a fibrillar infrastructure which does not extend over plasmalemmal vesicles but on which the latter appear to be anchored by fine filaments.

  4. Minimal experimental requirements for definition of extracellular vesicles and their functions : a position statement from the International Society for Extracellular Vesicles

    NARCIS (Netherlands)

    Lötvall, Jan; Hill, Andrew F; Hochberg, Fred; Buzás, Edit I; Di Vizio, Dolores; Gardiner, Christopher; Gho, Yong Song; Kurochkin, Igor V; Mathivanan, Suresh; Quesenberry, Peter; Sahoo, Susmita; Tahara, Hidetoshi; Wauben, Marca H|info:eu-repo/dai/nl/112675735; Witwer, Kenneth W; Théry, Clotilde

    2014-01-01

    Secreted membrane-enclosed vesicles, collectively called extracellular vesicles (EVs), which include exosomes, ectosomes, microvesicles, microparticles, apoptotic bodies and other EV subsets, encompass a very rapidly growing scientific field in biology and medicine. Importantly, it is currently

  5. Sodium sulfur battery seal

    Science.gov (United States)

    Mikkor, Mati

    1981-01-01

    This disclosure is directed to an improvement in a sodium sulfur battery construction in which a seal between various battery compartments is made by a structure in which a soft metal seal member is held in a sealing position by holding structure. A pressure applying structure is used to apply pressure on the soft metal seal member when it is being held in sealing relationship to a surface of a container member of the sodium sulfur battery by the holding structure. The improvement comprises including a thin, well-adhered, soft metal layer on the surface of the container member of the sodium sulfur battery to which the soft metal seal member is to be bonded.

  6. Direct imaging of RAB27B-enriched secretory vesicle biogenesis in lacrimal acinar cells reveals origins on a nascent vesicle budding site.

    Directory of Open Access Journals (Sweden)

    Lilian Chiang

    Full Text Available This study uses YFP-tagged Rab27b expression in rabbit lacrimal gland acinar cells, which are polarized secretory epithelial cells, to characterize early stages of secretory vesicle trafficking. Here we demonstrate the utility of YFP-Rab27b to delineate new perspectives on the mechanisms of early vesicle biogenesis in lacrimal gland acinar cells, where information is significantly limited. Protocols were developed to deplete the mature YFP-Rab27b-enriched secretory vesicle pool in the subapical region of the cell, and confocal fluorescence microscopy was used to track vesicle replenishment. This analysis revealed a basally-localized organelle, which we termed the "nascent vesicle site," from which nascent vesicles appeared to emerge. Subapical vesicular YFP-Rab27b was co-localized with p150(Glued, a component of the dynactin cofactor of cytoplasmic dynein. Treatment with the microtubule-targeted agent, nocodazole, did not affect release of mature secretory vesicles, although during vesicle repletion it significantly altered nascent YFP-Rab27b-enriched secretory vesicle localization. Instead of moving to the subapical region, these vesicles were trapped at the nascent vesicle site which was adjacent to, if not a sub-compartment of, the trans-Golgi network. Finally, YFP-Rab27b-enriched secretory vesicles which reached the subapical cytoplasm appeared to acquire the actin-based motor protein, Myosin 5C. Our findings show that Rab27b enrichment occurs early in secretory vesicle formation, that secretory vesicles bud from a visually discernable nascent vesicle site, and that transport from the nascent vesicle site to the subapical region requires intact microtubules.

  7. Too Much Sodium

    Centers for Disease Control (CDC) Podcasts

    2012-02-07

    This podcast is based on the February 2012 CDC Vital Signs report. Ninety percent of Americans age two and older eat too much sodium which can increase your risk for high blood pressure and often leads to heart disease and stroke, two leading causes of death in the US. Learn several small steps you can take to reduce the amount of sodium in your diet.  Created: 2/7/2012 by Centers for Disease Control and Prevention (CDC).   Date Released: 2/7/2012.

  8. Mutations in the major gas vesicle protein GvpA and impacts on gas vesicle formation in Haloferax volcanii.

    Science.gov (United States)

    Knitsch, Regine; Schneefeld, Marie; Weitzel, Kerstin; Pfeifer, Felicitas

    2017-09-12

    Gas vesicles are proteinaceous, gas-filled nanostructures produced by some bacteria and archaea. The hydrophobic major structural protein GvpA forms the ribbed gas vesicle wall. An in-silico 3D-model of GvpA of the predicted coil-α1-β1-β2-α2-coil structure is available and implies that the two β-chains constitute the hydrophobic interior surface of the gas vesicle wall. To test the importance of individual amino acids in GvpA we performed 85 single substitutions and analyzed these variants in Haloferax volcanii ΔA + Amut transformants for their ability to form gas vesicles (Vac(+) phenotype). In most cases, an alanine substitution of a non-polar residue did not abolish gas vesicle formation, but the replacement of single non-polar by charged residues in β1 or β2 resulted in Vac(-) transformants. A replacement of residues near the β-turn altered the spindle-shape to a cylindrical morphology of the gas vesicles. Vac(-) transformants were also obtained with alanine substitutions of charged residues of helix α1 suggesting that these amino acids form salt-bridges with another GvpA monomer. In helix α2, only the alanine substitution of His53 or Tyr54, led to Vac(-) transformants, whereas most other substitutions had no effect. We discuss our results in respect to the GvpA structure and data available from solid-state NMR. © 2017 John Wiley & Sons Ltd.

  9. Focus on Extracellular Vesicles: Physiological Role and Signalling Properties of Extracellular Membrane Vesicles

    Directory of Open Access Journals (Sweden)

    Nunzio Iraci

    2016-02-01

    Full Text Available Extracellular vesicles (EVs are a heterogeneous population of secreted membrane vesicles, with distinct biogenesis routes, biophysical properties and different functions both in physiological conditions and in disease. The release of EVs is a widespread biological process, which is conserved across species. In recent years, numerous studies have demonstrated that several bioactive molecules are trafficked with(in EVs, such as microRNAs, mRNAs, proteins and lipids. The understanding of their final impact on the biology of specific target cells remains matter of intense debate in the field. Also, EVs have attracted great interest as potential novel cell-free therapeutics. Here we describe the proposed physiological and pathological functions of EVs, with a particular focus on their molecular content. Also, we discuss the advances in the knowledge of the mechanisms regulating the secretion of EV-associated molecules and the specific pathways activated upon interaction with the target cell, highlighting the role of EVs in the context of the immune system and as mediators of the intercellular signalling in the brain.

  10. Focus on Extracellular Vesicles: Physiological Role and Signalling Properties of Extracellular Membrane Vesicles.

    Science.gov (United States)

    Iraci, Nunzio; Leonardi, Tommaso; Gessler, Florian; Vega, Beatriz; Pluchino, Stefano

    2016-02-06

    Extracellular vesicles (EVs) are a heterogeneous population of secreted membrane vesicles, with distinct biogenesis routes, biophysical properties and different functions both in physiological conditions and in disease. The release of EVs is a widespread biological process, which is conserved across species. In recent years, numerous studies have demonstrated that several bioactive molecules are trafficked with(in) EVs, such as microRNAs, mRNAs, proteins and lipids. The understanding of their final impact on the biology of specific target cells remains matter of intense debate in the field. Also, EVs have attracted great interest as potential novel cell-free therapeutics. Here we describe the proposed physiological and pathological functions of EVs, with a particular focus on their molecular content. Also, we discuss the advances in the knowledge of the mechanisms regulating the secretion of EV-associated molecules and the specific pathways activated upon interaction with the target cell, highlighting the role of EVs in the context of the immune system and as mediators of the intercellular signalling in the brain.

  11. Sugar-based gemini surfactant with a vesicle-to-micelle transition at acidic pH and a reversible vesicle flocculation near neutral pH

    NARCIS (Netherlands)

    Johnsson, M; Wagenaar, A; Engberts, JBFN

    2003-01-01

    A sugar-based (reduced glucose) gemini surfactant forms vesicles in dilute aqueous solution near neutral pH. At lower pH, there is a vesicle-to-micelle transition within a narrow pH region (pH 6.0-5.6). The vesicles are transformed into large cylindrical micelles that in turn are transformed into

  12. Procoagulant extracellular vesicles in amniotic fluid.

    Science.gov (United States)

    Hell, Lena; Wisgrill, Lukas; Ay, Cihan; Spittler, Andreas; Schwameis, Michael; Jilma, Bernd; Pabinger, Ingrid; Altevogt, Peter; Thaler, Johannes

    2017-06-01

    Embolization of amniotic fluid (AF) into the blood circulation leads to disseminated intravascular coagulation (DIC). Procoagulant phosphatidylserine (PS)- and tissue factor (TF)-exposing extracellular vesicles (EVs) might play an important role in AF embolism-induced DIC. It was the aim of the present study to perform analyses of the procoagulant properties of AF with a panel of functional coagulation assays and flow cytometry. We applied a prothrombinase assay (that quantifies PS exposure on EVs), an EV-associated TF activity assay, a fibrin generation assay, a thrombin generation assay, a whole blood clotting model, and flow cytometry in AF and control plasma. We found that PS exposure on EVs was 21-fold increased in AF compared with plasma. Also, EV-associated TF activity was highly increased in AF compared with plasma. AF-derived EVs activated the blood coagulation cascade via PS and TF in the fibrin and thrombin generation assays. In a whole blood clotting model, AF-derived EVs significantly shortened the clotting time from 734 ± 139 seconds in the presence to 232 ± 139 seconds in the absence of an anti-TF antibody. The contact activation pathway via factor XII (FXII) was not affected. Applying flow cytometry, a subpopulation of PS+ and TF+ EVs was identified in AF but not in control plasma. In conclusion, we investigated the effect of AF on blood coagulation and found that PS+ and TF+ EVs determine their procoagulant potential. Taken together, our data further delineate the pathomechanisms underlying AF-induced coagulopathy. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Surface glycosylation profiles of urine extracellular vesicles.

    Directory of Open Access Journals (Sweden)

    Jared Q Gerlach

    Full Text Available Urinary extracellular vesicles (uEVs are released by cells throughout the nephron and contain biomolecules from their cells of origin. Although uEV-associated proteins and RNA have been studied in detail, little information exists regarding uEV glycosylation characteristics. Surface glycosylation profiling by flow cytometry and lectin microarray was applied to uEVs enriched from urine of healthy adults by ultracentrifugation and centrifugal filtration. The carbohydrate specificity of lectin microarray profiles was confirmed by competitive sugar inhibition and carbohydrate-specific enzyme hydrolysis. Glycosylation profiles of uEVs and purified Tamm Horsfall protein were compared. In both flow cytometry and lectin microarray assays, uEVs demonstrated surface binding, at low to moderate intensities, of a broad range of lectins whether prepared by ultracentrifugation or centrifugal filtration. In general, ultracentrifugation-prepared uEVs demonstrated higher lectin binding intensities than centrifugal filtration-prepared uEVs consistent with lesser amounts of co-purified non-vesicular proteins. The surface glycosylation profiles of uEVs showed little inter-individual variation and were distinct from those of Tamm Horsfall protein, which bound a limited number of lectins. In a pilot study, lectin microarray was used to compare uEVs from individuals with autosomal dominant polycystic kidney disease to those of age-matched controls. The lectin microarray profiles of polycystic kidney disease and healthy uEVs showed differences in binding intensity of 6/43 lectins. Our results reveal a complex surface glycosylation profile of uEVs that is accessible to lectin-based analysis following multiple uEV enrichment techniques, is distinct from co-purified Tamm Horsfall protein and may demonstrate disease-specific modifications.

  14. Sodium Phosphate Rectal

    Science.gov (United States)

    ... liquid using a measuring spoon. Then replace the bottle cap.To use the sodium phosphate enema, follow these steps: Remove the protective shield from the tip of the enema. Lie down on ... insert the enema bottle into your rectum with the tip pointing toward ...

  15. Cardiac sodium channelopathies

    NARCIS (Netherlands)

    Amin, Ahmad S.; Asghari-Roodsari, Alaleh; Tan, Hanno L.

    2010-01-01

    Cardiac sodium channel are protein complexes that are expressed in the sarcolemma of cardiomyocytes to carry a large inward depolarizing current (I-Na) during phase 0 of the cardiac action potential. The importance of I-Na for normal cardiac electrical activity is reflected by the high incidence of

  16. Sodium fluxes in sweet pepper exposed to varying sodium concentrations

    NARCIS (Netherlands)

    Blom-Zandstra, M.; Vogelzang, S.A.; Veen, B.W.

    1998-01-01

    The sodium transport and distribution of sweet pepper (Capsicum annuum L.) under saline conditions were studied after transferring the plants to a sodium-free nutrient solution. Sodium stress up to 60 mM did not affect the growth of sweet pepper, as it appears able to counteract the unfavourable

  17. Melanoma affects the composition of blood cell-derived extracellular vesicles

    Directory of Open Access Journals (Sweden)

    Nina Koliha

    2016-07-01

    Full Text Available Extracellular vesicles are specifically loaded with nucleic acids, lipids, and proteins from their parental cell. Therefore, the constitution of extracellular vesicles reflects the type and status of the originating cell and extracellular vesicles in melanoma patient’s plasma could be indicative for the tumor. Likewise, extracellular vesicles might influence tumor progression by regulating immune responses. We performed a broad protein characterization of extracellular vesicles from plasma of melanoma patients and healthy donors as well as from T cells, B cells, natural killer cells, monocytes, monocyte-derived dendritic cells and platelets using a multiplex bead-based platform. Using this method, we succeeded in analyzing 58 proteins that were differentially displayed on extracellular vesicles. Hierarchal clustering of protein intensity patterns grouped extracellular vesicles according to their originating cell type. The analysis of extracellular vesicles from stimulated B cells and monocyte-derived dendritic cells revealed the transfer of surface proteins to vesicles depending on the cell status. The protein profiles of plasma vesicles resembled the protein profiles of extracellular vesicles from platelets, antigen presenting cells and natural cells as shown by platelet markers, costimulatory proteins, and a natural killer cell subpopulation marker. In comparison to healthy plasma vesicles, melanoma plasma vesicles showed altered signals for platelet markers indicating a changed vesicle secretion or protein loading of extracellular vesicles by platelets and a lower CD8 signal that might be associated with a diminished activity of natural killer cells or T cells. As we hardly detected melanoma-derived vesicles in patient’s plasma, we concluded that blood cells induced the observed differences. In summary, our results question a direct effect of melanoma cells on the composition of extracellular vesicles in melanoma plasma, but rather argue

  18. α-Synuclein Dimers Impair Vesicle Fission during Clathrin-Mediated Synaptic Vesicle Recycling

    Directory of Open Access Journals (Sweden)

    Audrey T. Medeiros

    2017-12-01

    Full Text Available α-Synuclein is a presynaptic protein that regulates synaptic vesicle (SV trafficking. In Parkinson’s disease (PD and several other neurodegenerative disorders, aberrant oligomerization and aggregation of α-synuclein lead to synaptic dysfunction and neurotoxicity. Despite evidence that α-synuclein oligomers are generated within neurons under physiological conditions, and that altering the balance of monomers and oligomers contributes to disease pathogenesis, how each molecular species of α-synuclein impacts SV trafficking is currently unknown. To address this, we have taken advantage of lamprey giant reticulospinal (RS synapses, which are accessible to acute perturbations via axonal microinjection of recombinant proteins. We previously reported that acute introduction of monomeric α-synuclein inhibited SV recycling, including effects on the clathrin pathway. Here, we report the effects of α-synuclein dimers at synapses. Similar to monomeric α-synuclein, both recombinant α-synuclein dimers that were evaluated bound to small liposomes containing anionic lipids in vitro, but with reduced efficacy. When introduced to synapses, the α-synuclein dimers also induced SV recycling defects, which included a build up of clathrin-coated pits (CCPs with constricted necks that were still attached to the plasma membrane, a phenotype indicative of a vesicle fission defect. Interestingly, both α-synuclein dimers induced longer necks on CCPs as well as complex, branching membrane tubules, which were distinct from the CCPs induced by a dynamin inhibitor, Dynasore. In contrast, monomeric α-synuclein induced a buildup of free clathrin-coated vesicles (CCVs, indicating an inhibition of clathrin-mediated endocytosis at a later stage during the clathrin uncoating process. Taken together, these data further support the conclusion that excess α-synuclein impairs SV recycling. The data additionally reveal that monomeric and dimeric α-synuclein produce

  19. End-capping of amphiphilic nanotubes with phospholipid vesicles: impact of the phospholipid on the cap formation and vesicle loading under osmotic conditions.

    Science.gov (United States)

    Erne, Petra M; Štacko, Peter; van Dijken, Derk Jan; Chen, Jiawen; Stuart, Marc C A; Feringa, Ben L

    2016-09-22

    Soft amphiphilic nanotubes are capped with vesicles comprised of either overall neutral, zwitterionic phospholipids, or those that carry a net charge. The phase transition temperature of the zwitterionic phospholipids plays a crucial role in the phase separation that leads to the end-capped nanotubes. The cationic vesicle caps can be loaded into the nanotubes via osmosis whereas the anionic vesicle caps are stable under hyper-osmotic conditions. Furthermore, no additional salt needs to be added for the cationic vesicle caps to induce the loading of the vesicles into the nanotubes due to the presence of counterions.

  20. Discovering vesicle traffic network constraints by model checking.

    Science.gov (United States)

    Shukla, Ankit; Bhattacharyya, Arnab; Kuppusamy, Lakshmanan; Srivas, Mandayam; Thattai, Mukund

    2017-01-01

    A eukaryotic cell contains multiple membrane-bound compartments. Transport vesicles move cargo between these compartments, just as trucks move cargo between warehouses. These processes are regulated by specific molecular interactions, as summarized in the Rothman-Schekman-Sudhof model of vesicle traffic. The whole structure can be represented as a transport graph: each organelle is a node, and each vesicle route is a directed edge. What constraints must such a graph satisfy, if it is to represent a biologically realizable vesicle traffic network? Graph connectedness is an informative feature: 2-connectedness is necessary and sufficient for mass balance, but stronger conditions are required to ensure correct molecular specificity. Here we use Boolean satisfiability (SAT) and model checking as a framework to discover and verify graph constraints. The poor scalability of SAT model checkers often prevents their broad application. By exploiting the special structure of the problem, we scale our model checker to vesicle traffic systems with reasonably large numbers of molecules and compartments. This allows us to test a range of hypotheses about graph connectivity, which can later be proved in full generality by other methods.

  1. Vesicle shape, molecular tilt, and the suppression of necks

    Science.gov (United States)

    Jiang, Hongyuan; Huber, Greg; Pelcovits, Robert A.; Powers, Thomas R.

    2007-09-01

    Can the presence of molecular-tilt order significantly affect the shapes of lipid bilayer membranes, particularly membrane shapes with narrow necks? Motivated by the propensity for tilt order and the common occurrence of narrow necks in the intermediate stages of biological processes such as endocytosis and vesicle trafficking, we examine how tilt order inhibits the formation of necks in the equilibrium shapes of vesicles. For vesicles with a spherical topology, point defects in the molecular order with a total strength of +2 are required. We study axisymmetric shapes and suppose that there is a unit-strength defect at each pole of the vesicle. The model is further simplified by the assumption of tilt isotropy: invariance of the energy with respect to rotations of the molecules about the local membrane normal. This isotropy condition leads to a minimal coupling of tilt order and curvature, giving a high energetic cost to regions with Gaussian curvature and tilt order. Minimizing the elastic free energy with constraints of fixed area and fixed enclosed volume determines the allowed shapes. Using numerical calculations, we find several branches of solutions and identify them with the branches previously known for fluid membranes. We find that tilt order changes the relative energy of the branches, suppressing thin necks by making them costly, leading to elongated prolate vesicles as a generic family of tilt-ordered membrane shapes.

  2. Souffle/Spastizin Controls Secretory Vesicle Maturation during Zebrafish Oogenesis

    Science.gov (United States)

    Riedel, Dietmar; Schomburg, Christoph; Cerdà, Joan; Vollack, Nadine; Dosch, Roland

    2014-01-01

    During oogenesis, the egg prepares for fertilization and early embryogenesis. As a consequence, vesicle transport is very active during vitellogenesis, and oocytes are an outstanding system to study regulators of membrane trafficking. Here, we combine zebrafish genetics and the oocyte model to identify the molecular lesion underlying the zebrafish souffle (suf) mutation. We demonstrate that suf encodes the homolog of the Hereditary Spastic Paraplegia (HSP) gene SPASTIZIN (SPG15). We show that in zebrafish oocytes suf mutants accumulate Rab11b-positive vesicles, but trafficking of recycling endosomes is not affected. Instead, we detect Suf/Spastizin on cortical granules, which undergo regulated secretion. We demonstrate genetically that Suf is essential for granule maturation into secretion competent dense-core vesicles describing a novel role for Suf in vesicle maturation. Interestingly, in suf mutants immature, secretory precursors accumulate, because they fail to pinch-off Clathrin-coated buds. Moreover, pharmacological inhibition of the abscission regulator Dynamin leads to an accumulation of immature secretory granules and mimics the suf phenotype. Our results identify a novel regulator of secretory vesicle formation in the zebrafish oocyte. In addition, we describe an uncharacterized cellular mechanism for Suf/Spastizin activity during secretion, which raises the possibility of novel therapeutic avenues for HSP research. PMID:24967841

  3. Souffle/Spastizin controls secretory vesicle maturation during zebrafish oogenesis.

    Directory of Open Access Journals (Sweden)

    Palsamy Kanagaraj

    2014-06-01

    Full Text Available During oogenesis, the egg prepares for fertilization and early embryogenesis. As a consequence, vesicle transport is very active during vitellogenesis, and oocytes are an outstanding system to study regulators of membrane trafficking. Here, we combine zebrafish genetics and the oocyte model to identify the molecular lesion underlying the zebrafish souffle (suf mutation. We demonstrate that suf encodes the homolog of the Hereditary Spastic Paraplegia (HSP gene SPASTIZIN (SPG15. We show that in zebrafish oocytes suf mutants accumulate Rab11b-positive vesicles, but trafficking of recycling endosomes is not affected. Instead, we detect Suf/Spastizin on cortical granules, which undergo regulated secretion. We demonstrate genetically that Suf is essential for granule maturation into secretion competent dense-core vesicles describing a novel role for Suf in vesicle maturation. Interestingly, in suf mutants immature, secretory precursors accumulate, because they fail to pinch-off Clathrin-coated buds. Moreover, pharmacological inhibition of the abscission regulator Dynamin leads to an accumulation of immature secretory granules and mimics the suf phenotype. Our results identify a novel regulator of secretory vesicle formation in the zebrafish oocyte. In addition, we describe an uncharacterized cellular mechanism for Suf/Spastizin activity during secretion, which raises the possibility of novel therapeutic avenues for HSP research.

  4. Overall energy conversion efficiency of a photosynthetic vesicle.

    Science.gov (United States)

    Sener, Melih; Strumpfer, Johan; Singharoy, Abhishek; Hunter, C Neil; Schulten, Klaus

    2016-08-26

    The chromatophore of purple bacteria is an intracellular spherical vesicle that exists in numerous copies in the cell and that efficiently converts sunlight into ATP synthesis, operating typically under low light conditions. Building on an atomic-level structural model of a low-light-adapted chromatophore vesicle from Rhodobacter sphaeroides, we investigate the cooperation between more than a hundred protein complexes in the vesicle. The steady-state ATP production rate as a function of incident light intensity is determined after identifying quinol turnover at the cytochrome bc1 complex (cytb⁢c1) as rate limiting and assuming that the quinone/quinol pool of about 900 molecules acts in a quasi-stationary state. For an illumination condition equivalent to 1% of full sunlight, the vesicle exhibits an ATP production rate of 82 ATP molecules/s. The energy conversion efficiency of ATP synthesis at illuminations corresponding to 1%-5% of full sunlight is calculated to be 0.12-0.04, respectively. The vesicle stoichiometry, evolutionarily adapted to the low light intensities in the habitat of purple bacteria, is suboptimal for steady-state ATP turnover for the benefit of protection against over-illumination.

  5. Biodegradable theranostic plasmonic vesicles of amphiphilic gold nanorods.

    Science.gov (United States)

    Song, Jibin; Pu, Lu; Zhou, Jiajing; Duan, Bo; Duan, Hongwei

    2013-11-26

    We have developed surface-initiated organocatalytic ring-opening polymerization on functional nanocrystals and synthesized amphiphilic gold nanorods carrying well-defined mixed polymer brushes of poly(ethylene glycol) and polylactide. Self-assembly of the amphiphilic gold nanorods affords biodegradable plasmonic vesicles that can be destructed by both enzymatic degradation and near-infrared photothermal heating. When tagged with Raman probes, strongly coupled gold nanorods in the self-assembled vesicles give rise to highly active SERS signals. The biodegradable plasmonic vesicles exhibit a unique combination of optical and structural properties that are of particular interest for theranostic applications. We have demonstrated that bioconjugated SERS-active plasmonic vesicles can specifically target EpCAM-positive cancer cells, leading to ultrasensitive spectroscopic detection of cancer cells. Furthermore, integration of photothermal effect of gold nanorods and large loading capacity of the vesicles provides opportunities for localized synergistic photothermal ablation and photoactivated chemotherapy, which have shown higher efficiency in killing targeted cancer cells than either single therapeutic modality. The versatile chemistry of organocatalytic ring-opening polymerization, in conjugation with recent development in synthesizing functional nanocrystals with tailored optical, electronic, and magnetic properties opens the possibilities for constructing multifunctional biodegradable platforms for clinical translation.

  6. Slicing sodium from bakery products

    NARCIS (Netherlands)

    Noort, M.

    2012-01-01

    The need for sodium reduction in our diet is clear to consumers, dieticians and food manufacturers. As sodium concentration has a strengthening effect on gluten, sodium reduction decreases dough mixing tolerance, dough resistance and induces dough stickiness. In particular, the latter may cause

  7. Hanford site sodium management plan

    Energy Technology Data Exchange (ETDEWEB)

    Guttenberg, S.

    1995-09-25

    The Hanford Site Sodium Management Plan, Revision 1, provides changes to the major elements and management strategy to ensure an integrated and coordinated approach for disposition of the more than 350,000 gallons of sodium and related sodium facilities located at the DOE`s Hanford Site

  8. Characteristic spatial scale of vesicle pair interactions in a plane linear flow.

    Science.gov (United States)

    Levant, Michael; Deschamps, Julien; Afik, Eldad; Steinberg, Victor

    2012-05-01

    We report the experimental studies on interaction of two vesicles trapped in a microfluidic four-roll mill, where a plane linear flow is realized. We found that the dynamics of a vesicle in tank-treading motion is significantly altered by the presence of another vesicle at separation distances up to 3.2-3.7 times of the vesicle effective radius. This result is supported by measurement of a single vesicle back-reaction on the velocity field. Thus the experiment provides the upper bound for the volume fraction φ = 0.08-0.13 of noninteracting vesicle suspensions.

  9. Characterization of extracellular vesicles in whole blood: Influence of pre-analytical parameters and visualization of vesicle-cell interactions using imaging flow cytometry.

    Science.gov (United States)

    Fendl, Birgit; Weiss, René; Fischer, Michael B; Spittler, Andreas; Weber, Viktoria

    2016-09-09

    Extracellular vesicles are central players in intercellular communication and are released from the plasma membrane under tightly regulated conditions, depending on the physiological and pathophysiological state of the producing cell. Their heterogeneity requires a spectrum of methods for isolation and characterization, where pre-analytical parameters have profound impact on vesicle analysis, particularly in blood, since sampling, addition of anticoagulants, as well as post-sampling vesicle generation may influence the outcome. Here, we characterized microvesicles directly in whole blood using a combination of flow cytometry and imaging flow cytometry. We assessed the influence of sample agitation, anticoagulation, and temperature on post-sampling vesicle generation, and show that vesicle counts remained stable over time in samples stored without agitation. Storage with gentle rolling mimicking agitation, in contrast, resulted in strong release of platelet-derived vesicles in blood anticoagulated with citrate or heparin, whereas vesicle counts remained stable upon anticoagulation with EDTA. Using imaging flow cytometry, we could visualize microvesicles adhering to blood cells and revealed an anticoagulant-dependent increase in vesicle-cell aggregates over time. We demonstrate that vesicles adhere preferentially to monocytes and granulocytes in whole blood, while no microvesicles could be visualized on lymphocytes. Our data underscore the relevance of pre-analytical parameters in vesicle analysis and demonstrate that imaging flow cytometry is a suitable tool to study the interaction of extracellular vesicles with their target cells. Copyright © 2016 Elsevier Inc. All rights reserved.

  10. Immobilization of stable thylakoid vesicles in conductive nanofibers by electrospinning.

    Science.gov (United States)

    Bedford, Nicholas M; Winget, G Douglas; Punnamaraju, Srikoundinya; Steckl, Andrew J

    2011-03-14

    Electrospun fibers consisting of poly(3,4-ethylenedioxythiophene)/poly(styrene sulfonate) (PEDOT/PSS) and poly(ethylene oxide) (PEO) have been used to successfully encapsulate and stabilize thylakoid membrane vesicles isolated from spinach. Light-driven electronic properties were measured. Fibers with immobilized thylakoids show higher electrical conductivity compared with fibers without thylakoids under white light conditions. This is attributed to the electron-generating photosynthetic reactions from the thylakoids. Electron and optical microscopy show the presence of thylakoid vesicles within the fibers using lipid-specific stains. After electrospinning into fibers, the thylakoid vesicles still exhibit an ability to produce a light-driven electron gradient, indicating that activity is preserved during the electrospinning process. These electrospun fibers provide an excellent example of incorporating photosynthetic function into an artificial system.

  11. Dynamics of Shape Fluctuations of Quasi-spherical Vesicles Revisited

    DEFF Research Database (Denmark)

    Miao, L.; Lomholt, Michael Andersen; Kleis, J.

    2002-01-01

    of the phenomenological constants in a canonical continuum description of fluid lipid-bilayer membranes and shown the consequences of this new interpretation in terms of the characteristics of the dynamics of vesicle shape fluctuations. Moreover, we have used the systematic formulation of our theory as a framework...... against which we have discussed the previously existing theories and their discrepancies. Finally, we have made a systematic prediction about the system-dependent characteristics of the relaxation dynamics of shape fluctuations of quasi-spherical vesicles with a view of experimental studies......In this paper, the dynamics of spontaneous shape fluctuations of a single, giant quasi-spherical vesicle formed from a single lipid species is revisited theoretically. A coherent physical theory for the dynamics is developed based on a number of fundamental principles and considerations...

  12. Exosomes and other extracellular vesicles in host–pathogen interactions

    Science.gov (United States)

    Schorey, Jeffrey S; Cheng, Yong; Singh, Prachi P; Smith, Victoria L

    2015-01-01

    An effective immune response requires the engagement of host receptors by pathogen-derived molecules and the stimulation of an appropriate cellular response. Therefore, a crucial factor in our ability to control an infection is the accessibility of our immune cells to the foreign material. Exosomes—which are extracellular vesicles that function in intercellular communication—may play a key role in the dissemination of pathogen- as well as host-derived molecules during infection. In this review, we highlight the composition and function of exosomes and other extracellular vesicles produced during viral, parasitic, fungal and bacterial infections and describe how these vesicles could function to either promote or inhibit host immunity. PMID:25488940

  13. Extracellular Vesicles in Brain Tumors and Neurodegenerative Diseases

    Directory of Open Access Journals (Sweden)

    Federica Ciregia

    2017-08-01

    Full Text Available Extracellular vesicles (EVs can be classified into apoptotic bodies, microvesicles (MVs, and exosomes, based on their origin or size. Exosomes are the smallest and best characterized vesicles which derived from the endosomal system. These vesicles are released from many different cell types including neuronal cells and their functions in the nervous system are investigated. They have been proposed as novel means for intercellular communication, which takes part not only to the normal neuronal physiology but also to the transmission of pathogenic proteins. Indeed, exosomes are fundamental to assemble and transport proteins during development, but they can also transfer neurotoxic misfolded proteins in pathogenesis. The present review will focus on their roles in neurological diseases, specifically brain tumors, such as glioblastoma (GBM, neuroblastoma (NB, medulloblastoma (MB, and metastatic brain tumors and chronic neurodegenerative diseases, such as Alzheimer, Parkinson, multiple sclerosis (MS, amyotrophic lateral sclerosis (ALS, Huntington, and Prion diseseases highlighting their involvement in spreading neurotoxicity, in therapeutics, and in pathogenesis.

  14. Extracellular Vesicles in Brain Tumors and Neurodegenerative Diseases

    Science.gov (United States)

    Ciregia, Federica; Urbani, Andrea; Palmisano, Giuseppe

    2017-01-01

    Extracellular vesicles (EVs) can be classified into apoptotic bodies, microvesicles (MVs), and exosomes, based on their origin or size. Exosomes are the smallest and best characterized vesicles which derived from the endosomal system. These vesicles are released from many different cell types including neuronal cells and their functions in the nervous system are investigated. They have been proposed as novel means for intercellular communication, which takes part not only to the normal neuronal physiology but also to the transmission of pathogenic proteins. Indeed, exosomes are fundamental to assemble and transport proteins during development, but they can also transfer neurotoxic misfolded proteins in pathogenesis. The present review will focus on their roles in neurological diseases, specifically brain tumors, such as glioblastoma (GBM), neuroblastoma (NB), medulloblastoma (MB), and metastatic brain tumors and chronic neurodegenerative diseases, such as Alzheimer, Parkinson, multiple sclerosis (MS), amyotrophic lateral sclerosis (ALS), Huntington, and Prion diseseases highlighting their involvement in spreading neurotoxicity, in therapeutics, and in pathogenesis. PMID:28912682

  15. A Network of Three Types of Filaments Organizes Synaptic Vesicles for Storage, Mobilization, and Docking.

    Science.gov (United States)

    Cole, Andy A; Chen, Xiaobing; Reese, Thomas S

    2016-03-16

    Synaptic transmission between neurons requires precise management of synaptic vesicles. While individual molecular components of the presynaptic terminal are well known, exactly how the molecules are organized into a molecular machine serving the storage and mobilization of synaptic vesicles to the active zone remains unclear. Here we report three filament types associated with synaptic vesicles in glutamatergic synapses revealed by electron microscope tomography in unstimulated, dissociated rat hippocampal neurons. One filament type, likely corresponding to the SNAREpin complex, extends from the active zone membrane and surrounds docked vesicles. A second filament type contacts all vesicles throughout the active zone and pairs vesicles together. On the third filament type, vesicles attach to side branches extending from the long filament core and form vesicle clusters that are distributed throughout the vesicle cloud and along the active zone membrane. Detailed analysis of presynaptic structure reveals how each of the three filament types interacts with synaptic vesicles, providing a means to traffic reserved and recycled vesicles from the cloud of vesicles into the docking position at the active zone. The formation and release of synaptic vesicles has been extensively investigated. Explanations of the release of synaptic vesicles generally begin with the movement of vesicles from the cloud into the synaptic active zone. However, the presynaptic terminal is filled with filamentous material that would appear to limit vesicular diffusion. Here, we provide a systematic description of three filament types connecting synaptic vesicles. A picture emerges illustrating how the cooperative attachment and release of these three filament types facilitate the movement of vesicles to the active zone to become docked in preparation for release. Copyright © 2016 the authors 0270-6474/16/363222-09$15.00/0.

  16. Cryo-electron microscopy of extracellular vesicles in fresh plasma.

    Science.gov (United States)

    Yuana, Yuana; Koning, Roman I; Kuil, Maxim E; Rensen, Patrick C N; Koster, Abraham J; Bertina, Rogier M; Osanto, Susanne

    2013-12-31

    Extracellular vesicles (EV) are phospholipid bilayer-enclosed vesicles recognized as new mediators in intercellular communication and potential biomarkers of disease. They are found in many body fluids and mainly studied in fractions isolated from blood plasma in view of their potential in medicine. Due to the limitations of available analytical methods, morphological information on EV in fresh plasma is still rather limited. To image EV and determine the morphology, structure and size distribution in fresh plasma by cryo-electron microscopy (cryo-EM). Fresh citrate- and ethylenediaminetetraacetic acid (EDTA)-anticoagulated plasma or EV isolated from these plasmas were rapidly cryo-immobilized by vitrification and visualized by cryo-EM. EV isolated from fresh plasma were highly heterogeneous in morphology and size and mostly contain a discernible lipid bilayer (lipid vesicles). In fresh plasma there were 2 types of particles with a median diameter of 30 nm (25-260 nm). The majority of these particles are electron dense particles which most likely represent lipoproteins. The minority are lipid vesicles, either electron dense or electron lucent, which most likely represent EV. Lipid vesicles were occasionally observed in close proximity of platelets in citrate and EDTA-anticoagulated platelet-rich plasma. Cryo-electron tomography (cryo-ET) was employed to determine the 3D structure of platelet secretory granules. Cryo-EM is a powerful technique that enables the characterization of EV in fresh plasma revealing structural details and considerable morphological heterogeneity. Only a small proportion of the submicron structures in fresh plasma are lipid vesicles representing EV.

  17. Cryo-electron microscopy of extracellular vesicles in fresh plasma

    Directory of Open Access Journals (Sweden)

    Yuana Yuana

    2013-12-01

    Full Text Available Introduction: Extracellular vesicles (EV are phospholipid bilayer-enclosed vesicles recognized as new mediators in intercellular communication and potential biomarkers of disease. They are found in many body fluids and mainly studied in fractions isolated from blood plasma in view of their potential in medicine. Due to the limitations of available analytical methods, morphological information on EV in fresh plasma is still rather limited. Objectives: To image EV and determine the morphology, structure and size distribution in fresh plasma by cryo-electron microscopy (cryo-EM. Methods: Fresh citrate- and ethylenediaminetetraacetic acid (EDTA-anticoagulated plasma or EV isolated from these plasmas were rapidly cryo-immobilized by vitrification and visualized by cryo-EM. Results: EV isolated from fresh plasma were highly heterogeneous in morphology and size and mostly contain a discernible lipid bilayer (lipid vesicles. In fresh plasma there were 2 types of particles with a median diameter of 30 nm (25–260 nm. The majority of these particles are electron dense particles which most likely represent lipoproteins. The minority are lipid vesicles, either electron dense or electron lucent, which most likely represent EV. Lipid vesicles were occasionally observed in close proximity of platelets in citrate and EDTA-anticoagulated platelet-rich plasma. Cryo-electron tomography (cryo-ET was employed to determine the 3D structure of platelet secretory granules. Conclusions: Cryo-EM is a powerful technique that enables the characterization of EV in fresh plasma revealing structural details and considerable morphological heterogeneity. Only a small proportion of the submicron structures in fresh plasma are lipid vesicles representing EV.

  18. Vesicle biomechanics in a time-varying magnetic field.

    Science.gov (United States)

    Ye, Hui; Curcuru, Austen

    2015-01-01

    Cells exhibit distortion when exposed to a strong electric field, suggesting that the field imposes control over cellular biomechanics. Closed pure lipid bilayer membranes (vesicles) have been widely used for the experimental and theoretical studies of cellular biomechanics under this electrodeformation. An alternative method used to generate an electric field is by electromagnetic induction with a time-varying magnetic field. References reporting the magnetic control of cellular mechanics have recently emerged. However, theoretical analysis of the cellular mechanics under a time-varying magnetic field is inadequate. We developed an analytical theory to investigate the biomechanics of a modeled vesicle under a time-varying magnetic field. Following previous publications and to simplify the calculation, this model treated the inner and suspending media as lossy dielectrics, the membrane thickness set at zero, and the electric resistance of the membrane assumed to be negligible. This work provided the first analytical solutions for the surface charges, electric field, radial pressure, overall translational forces, and rotational torques introduced on a vesicle by the time-varying magnetic field. Frequency responses of these measures were analyzed, particularly the frequency used clinically by transcranial magnetic stimulation (TMS). The induced surface charges interacted with the electric field to produce a biomechanical impact upon the vesicle. The distribution of the induced surface charges depended on the orientation of the coil and field frequency. The densities of these charges were trivial at low frequency ranges, but significant at high frequency ranges. The direction of the radial force on the vesicle was dependent on the conductivity ratio between the vesicle and the medium. At relatively low frequencies (biomechanics under a time-varying magnetic field. Biological effects of clinical TMS are not likely to occur via alteration of the biomechanics of brain

  19. 21 CFR 184.1736 - Sodium bicarbonate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Sodium bicarbonate. 184.1736 Section 184.1736 Food... Specific Substances Affirmed as GRAS § 184.1736 Sodium bicarbonate. (a) Sodium bicarbonate (NaHCO3, CAS Reg. No. 144-55-8) is prepared by treating a sodium carbonate or a sodium carbonate and sodium bicarbonate...

  20. 21 CFR 201.64 - Sodium labeling.

    Science.gov (United States)

    2010-04-01

    ... paragraph (b) of this section). (e) The term very low sodium may be used in the labeling of OTC drug... milligrams or less. (f) The term low sodium may be used in the labeling of OTC drug products intended for... substituted for the term sodium. (h) The terms sodium free, very low sodium, and low sodium shall be in print...

  1. Sodium intake and cardiovascular health.

    Science.gov (United States)

    O'Donnell, Martin; Mente, Andrew; Yusuf, Salim

    2015-03-13

    Sodium is an essential nutrient. Increasing sodium intake is associated with increasing blood pressure, whereas low sodium intake results in increased renin and aldosterone levels. Randomized controlled trials have reported reductions in blood pressure with reductions in sodium intake, to levels of sodium intake 6-month duration). It is assumed that the blood pressure-lowering effects of reducing sodium intake to low levels will result in large reductions in cardiovascular disease globally. However, current evidence from prospective cohort studies suggests a J-shaped association between sodium intake and cardiovascular events, based on studies from >300 000 people, and suggests that the lowest risk of cardiovascular events and death occurs in populations consuming an average sodium intake range (3-5 g/d). The increased risk of cardiovascular events associated with higher sodium intake (>5 g/d) is most prominent in those with hypertension. A major deficit in the field is the absence of large randomized controlled trials to provide definitive evidence on optimal sodium intake for preventing cardiovascular events. Pending such trials, current evidence would suggest a recommendation for moderate sodium intake in the general population (3-5 g/d), with targeting the lower end of the moderate range among those with hypertension. © 2015 American Heart Association, Inc.

  2. Electrolytes: Sodium Disorders.

    Science.gov (United States)

    Braun, Michael M; Mahowald, Megan

    2017-08-01

    Sodium disorders (ie, hyponatremia, hypernatremia) are common electrolyte disturbances in clinical medicine and are associated with increased rates of morbidity and mortality. Etiologies of hyponatremia are classified into four categories. The first is pseudohyponatremia, in which the sodium level is low due to hyperproteinemia, hyperlipidemia, or hyperglycemia. The other three categories are based on overall patient fluid status and include hypovolemic (commonly due to fluid loss), hypervolemic (commonly due to fluid retention from heart failure, cirrhosis, or renal failure), and euvolemic (most often because of syndrome of inappropriate secretion of antidiuretic hormone). Hypovolemic hyponatremia is managed by rehydration with isotonic saline. Hypervolemic hyponatremia is managed by addressing the underlying cause. Euvolemic hyponatremia is managed by restricting free water intake, addressing the underlying cause, and occasionally with drugs (eg, vasopressin receptor antagonists). Patients with severe or acutely symptomatic hyponatremia (eg, altered mental status, seizures), including those with acute symptomatic exercise-induced hyponatremia, require urgent treatment. This should consist of hypertonic saline administration along with monitoring of sodium levels to avoid overly rapid correction. Hypernatremia most often occurs because of water loss or inadequate water intake. Depending on severity, management involves oral or intravenous hypotonic fluids and addressing the underlying cause. Written permission from the American Academy of Family Physicians is required for reproduction of this material in whole or in part in any form or medium.

  3. Postcoital Hemorrhage of a Recurrent Seminal Vesicle Cyst Requiring Embolization

    Directory of Open Access Journals (Sweden)

    Eric Royston

    2014-09-01

    Full Text Available Herein is a case of a 23-year-old man with recurrence of a seminal vesicle cyst after percutaneous drainage and laparoscopic excision complicated by hemorrhage requiring embolization. He presented to the emergency department for pain after ejaculation. Computed tomographic scan of his pelvis revealed extravasation of contrast near his cyst and pelvic fluid collection suspicious for a hematoma. The patient had steadily decreasing hemoglobin and hematocrit levels. An interventional radiologist performed an embolization of the left seminal vesicle cystic arteries. Hemoglobin and hematocrit values improved and he was discharged. Hemorrhage resolved with embolization procedure and pain dissipated over the course of follow up care.

  4. Potentials and capabilities of the Extracellular Vesicle (EV Array

    Directory of Open Access Journals (Sweden)

    Malene Møller Jørgensen

    2015-04-01

    Full Text Available Extracellular vesicles (EVs and exosomes are difficult to enrich or purify from biofluids, hence quantification and phenotyping of these are tedious and inaccurate. The multiplexed, highly sensitive and high-throughput platform of the EV Array presented by Jørgensen et al., (J Extracell Vesicles, 2013; 2: 10 has been refined regarding the capabilities of the method for characterization and molecular profiling of EV surface markers. Here, we present an extended microarray platform to detect and phenotype plasma-derived EVs (optimized for exosomes for up to 60 antigens without any enrichment or purification prior to analysis.

  5. Proteomic analysis of cerebrospinal fluid extracellular vesicles: a comprehensive dataset.

    Science.gov (United States)

    Chiasserini, Davide; van Weering, Jan R T; Piersma, Sander R; Pham, Thang V; Malekzadeh, Arjan; Teunissen, Charlotte E; de Wit, Heidi; Jiménez, Connie R

    2014-06-25

    Extracellular vesicles (EVs) are present in human cerebrospinal fluid (CSF), yet little is known about their protein composition. The aim of this study is to provide a comprehensive analysis of the proteome of CSF EVs by electron microscopy and high resolution tandem mass spectrometry (MS/MS) in conjunction with bioinformatics. We report an extensive catalog of 1315 proteins identified in EVs isolated from two different CSF pools by ultracentrifugation, including 230 novel EV proteins. Out of 1315 proteins, 760 were identified in both CSF pools and about 30% of those were also quantitatively enriched in the EV fraction versus the soluble CSF fraction. The proteome of CSF EVs was enriched in exosomal markers such as alix and syntenin-1, heat shock proteins and tetraspanins and contained a high proportion of brain-derived proteins (n=373). Interestingly, several known biomarkers for neurodegenerative diseases such as the amyloid precursor protein, the prion protein and DJ-1 were identified in the EV fractions. Our dataset represents the first comprehensive inventory of the EV proteome in CSF, underscoring the biomarker potential of this organelle. Further comparative studies on CSF EVs isolated from patients diagnosed with neurological disorders are warranted. Data are available via ProteomeXchange with identifier PXD000608. Biological significance In this study we analyzed the protein composition of extracellular vesicles isolated from pooled samples of human cerebrospinal fluid (CSF). CSF is a colorless fluid surrounding the brain and the spinal cord, important for the physiology of the central nervous system, ensuing mechanical protection, regulation of brain blood flow and elimination of byproducts of the brain. Since brain (patho)physiology is reflected in CSF, this biological fluid represents an ideal source of soluble and vesicle-based biomarkers for neurological diseases. Here we confirm the presence of exosome-like extracellular vesicles in CSF, underscoring

  6. Erythrocyte-derived optical nano-vesicles as theranostic agents

    Science.gov (United States)

    Mac, Jenny T.; Nunez, Vicente; Bahmani, Baharak; Guerrero, Yadir; Tang, Jack; Vullev, Valentine I.; Anvari, Bahman

    2015-07-01

    We have engineered nano-vesicles, derived from erythrocytes, which can be doped with various near infrared (NIR) organic chromophores, including the FDA-approved indocyanine green (ICG). We refer to these vesicles as NIR erythrocyte-mimicking transducers (NETS) since in response to NIR photo-excitation they can generate heat or emit fluorescent light. Using biochemical methods based on reduction amination, we have functionalized the surface of NET with antibodies to target specific biomolecules. We present results that demonstrate the effectiveness of NETs in targeted imaging of cancer cells that over-express the human epidermal growth factor receptor-2 (HER2).

  7. MiR-21-5p in urinary extracellular vesicles is a novel biomarker of urothelial carcinoma

    OpenAIRE

    Matsuzaki, Kyosuke; Fujita, Kazutoshi; Jingushi, Kentaro; Kawashima, Atsunari; Ujike, Takeshi; Nagahara, Akira; Ueda, Yuko; Tanigawa, Go; Yoshioka, Iwao; Ueda, Koji; Hanayama, Rikinari; Uemura, Motohide; Miyagawa, Yasushi; Tsujikawa, Kazutake; Nonomura, Norio

    2017-01-01

    Background Extracellular vesicles are lipid bilayer vesicles containing protein, messengerRNA and microRNA. Cancer cell-derived extracellular vesicles may be diagnostic and therapeutic targets. We extracted extracellular vesicles from urine of urothelial carcinoma patients and the control group to identify cancer-specific microRNAs in urinary extracellular vesicles as new biomarkers. Materials and methods microRNA from urinary extracellular vesicles extracted from 6 urothelial carcinoma patie...

  8. Polymer/TiO₂ hybrid vesicles for excellent UV screening and effective encapsulation of antioxidant agents.

    Science.gov (United States)

    Du, Jianzhong; Sun, Hui

    2014-08-27

    Presented in this paper is a hybrid polymer/titanium dioxide (TiO2) vesicle that has excellent UV-screening efficacy and strong capacity to encapsulate antioxidant agents. Poly(ethylene oxide)-block-poly(2-(dimethylamino)ethyl methacrylate)-block-polystyrene (PEO-b-PDMAEMA-b-PS) triblock terpolymer was synthesized by atom transfer radical polymerization (ATRP) and then self-assembled into vesicles. Those vesicles showed excellent UV-screening property due to the scattering by vesicles and the absorption by PS vesicle membrane. The selective deposition of solvophobic tetrabutyl titanate in the PDMAEMA shell and the PS membrane of the vesicles led to the formation of polymer/TiO2 hybrid vesicles, resulting in an enhanced UV-screening property by further reflecting and scattering UV radiation. The vesicles can effectively encapsulate antioxidant agents such as ferulic acid (up to 57%), showing a rapid antioxidant capability (within 1 min) and a long-lasting antioxidant effect.

  9. Matrix-dependent local retention of secretory vesicle cargo in cortical neurons

    NARCIS (Netherlands)

    de Wit, J.; Toonen, R.F.G.; Verhage, M.

    2009-01-01

    Neurons secrete many diffusible signals from synaptic and other secretory vesicles. We characterized secretion of guidance cues, neuropeptides, neurotrophins, and proteases from single secretory vesicles using pHluorin-tagged cargo in cortical neurons. Stimulation triggered transient and persistent

  10. Engineering Globular Protein Vesicles through Tunable Self-Assembly of Recombinant Fusion Proteins.

    Science.gov (United States)

    Jang, Yeongseon; Choi, Won Tae; Heller, William T; Ke, Zunlong; Wright, Elizabeth R; Champion, Julie A

    2017-09-01

    Vesicles assembled from folded, globular proteins have potential for functions different from traditional lipid or polymeric vesicles. However, they also present challenges in understanding the assembly process and controlling vesicle properties. From detailed investigation of the assembly behavior of recombinant fusion proteins, this work reports a simple strategy to engineer protein vesicles containing functional, globular domains. This is achieved through tunable self-assembly of recombinant globular fusion proteins containing leucine zippers and elastin-like polypeptides. The fusion proteins form complexes in solution via high affinity binding of the zippers, and transition through dynamic coacervates to stable hollow vesicles upon warming. The thermal driving force, which can be tuned by protein concentration or temperature, controls both vesicle size and whether vesicles are single or bi-layered. These results provide critical information to engineer globular protein vesicles via self-assembly with desired size and membrane structure. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Introduction to Extracellular Vesicles: Biogenesis, RNA Cargo Selection, Content, Release, and Uptake.

    Science.gov (United States)

    Abels, Erik R; Breakefield, Xandra O

    2016-04-01

    Extracellular vesicles are a heterogeneous group of membrane-limited vesicles loaded with various proteins, lipids, and nucleic acids. Release of extracellular vesicles from its cell of origin occurs either through the outward budding of the plasma membrane or through the inward budding of the endosomal membrane, resulting in the formation of multivesicular bodies, which release vesicles upon fusion with the plasma membrane. The release of vesicles can facilitate intercellular communication by contact with or by internalization of contents, either by fusion with the plasma membrane or by endocytosis into "recipient" cells. Although the interest in extracellular vesicle research is increasing, there are still no real standards in place to separate or classify the different types of vesicles. This review provides an introduction into this expanding and complex field of research focusing on the biogenesis, nucleic acid cargo loading, content, release, and uptake of extracellular vesicles.

  12. Commercial cow milk contains physically stable extracellular vesicles expressing immunoregulatory TGF-beta

    NARCIS (Netherlands)

    Pieters, B.C.; Arntz, O.J.; Bennink, M.B.; Broeren, M.G.; Caam, A.P.M. van; Koenders, M.I.; Lent, P.L. van; Berg, W.B. van den; Vries, M. de; Kraan, P.M. van der; Loo, F.A.J. van de

    2015-01-01

    SCOPE: Extracellular vesicles, including exosomes, have been identified in all biological fluids and rediscovered as an important part of the intercellular communication. Breast milk also contains extracellular vesicles and the proposed biological function is to enhance the antimicrobial defense in

  13. Sodium regulation, sodium pump function and sodium pump inhibitors in uncomplicated pregnancy and preeclampsia.

    Science.gov (United States)

    Graves, Steven W

    2007-01-01

    Preeclampsia is a disease characterized by hypertension and proteinuria but can manifest many abnormalities. Some of the best documented alterations involve changes in the handling of sodium ion both on the systemic and on the cellular level. There is broad agreement that the components of the renin-angiotensin-aldosterone pathway are markedly reduced in women with preeclampsia. However, other changes, especially those involving cell sodium are less consistent. A majority of studies support an increase in peripheral cell sodium concentration. This would suggest a defect in (Na,K)ATPase or sodium pump activity. Direct study of cellular sodium pump activity provides suggestive but not unequivocal support for this decreased sodium pump activity. Other evidence indicates increased circulating concentrations of a sodium pump inhibitor in most, but not all, studies of preeclampsia. Together, current research argues more strongly in favor of derangements of cell sodium handling perhaps mediated by circulating sodium pump inhibitors leading often to increased cell sodium. Such an increase of cell sodium in vascular tissue has previously been shown to enhance vascular sensitivity to vasoconstrictor agents or lead directly to increased vasoconstriction.

  14. Single-step isolation of extracellular vesicles by size-exclusion chromatography

    OpenAIRE

    Böing, Anita N.; van der Pol, Edwin; Anita E. Grootemaat; Coumans, Frank A. W.; Sturk, Auguste; Nieuwland, Rienk

    2014-01-01

    Background: Isolation of extracellular vesicles from plasma is a challenge due to the presence of proteins and lipoproteins. Isolation of vesicles using differential centrifugation or density-gradient ultracentrifugation results in co-isolation of contaminants such as protein aggregates and incomplete separation of vesicles from lipoproteins, respectively.Aim: To develop a single-step protocol to isolate vesicles from human body fluids.Methods: Platelet-free supernatant, derived from platelet...

  15. Specific surface modification of the acetylene-linked glycolipid vesicle by click chemistry.

    Science.gov (United States)

    Ito, Hidehiro; Kamachi, Toshiaki; Yashima, Eiji

    2012-06-07

    A novel glycolipid with a terminal acetylene was synthesized and used to prepare unilamellar vesicles. Using these vesicles, a convenient method was developed for the specific modification of the vesicle surface using the photoresponsive copper complex [Cu(OH(2))(cage)] as the catalyst for a click reaction.

  16. Studies of matrix vesicle-induced mineralization in a gelatin gel

    Science.gov (United States)

    Boskey, A. L.; Boyan, B. D.; Doty, S. B.; Feliciano, A.; Greer, K.; Weiland, D.; Swain, L. D.; Schwartz, Z.

    1992-01-01

    Matrix vesicles isolated from fourth-passage cultures of chondrocytes were tested for their ability to induce hydroxyapatite formation in a gelatin gel in order to gain insight into the function of matrix vesicles in in situ mineralization. These matrix vesicles did not appear to be hydroxyapatite nucleators per se since the extent of mineral accumulation in the gel diffusion system was not altered by the presence of matrix vesicles alone, and in the vesicle containing gels, mineral crystals were formed whether associated with vesicles or not. In gels with these matrix vesicles and beta-glycerophosphate, despite the presence of alkaline phosphatase activity, there was no increase in mineral deposition. This suggested that in the gel system these culture-derived vesicles did not increase local phosphate concentrations. However, when known inhibitors of mineral crystal formation and growth (proteoglycan aggregates [4 mg/ml], or ATP [1 mM], or both proteoglycan and ATP) were included in the gel, more mineral was deposited in gels with the vesicles than in comparable gels without vesicles, indicating that enzymes within these vesicles were functioning to remove the inhibition. These data support the suggestion that one function of the extracellular matrix vesicles is to transport enzymes for matrix modification.

  17. Pseudomonas aeruginosa vesicles associate with and are internalized by human lung epithelial cells

    Directory of Open Access Journals (Sweden)

    Kuehn Meta J

    2009-02-01

    Full Text Available Abstract Background Pseudomonas aeruginosa is the major pathogen associated with chronic and ultimately fatal lung infections in patients with cystic fibrosis (CF. To investigate how P. aeruginosa-derived vesicles may contribute to lung disease, we explored their ability to associate with human lung cells. Results Purified vesicles associated with lung cells and were internalized in a time- and dose-dependent manner. Vesicles from a CF isolate exhibited a 3- to 4-fold greater association with lung cells than vesicles from the lab strain PAO1. Vesicle internalization was temperature-dependent and was inhibited by hypertonic sucrose and cyclodextrins. Surface-bound vesicles rarely colocalized with clathrin. Internalized vesicles colocalized with the endoplasmic reticulum (ER marker, TRAPα, as well as with ER-localized pools of cholera toxin and transferrin. CF isolates of P. aeruginosa abundantly secrete PaAP (PA2939, an aminopeptidase that associates with the surface of vesicles. Vesicles from a PaAP knockout strain exhibited a 40% decrease in cell association. Likewise, vesicles from PAO1 overexpressing PaAP displayed a significant increase in cell association. Conclusion These data reveal that PaAP promotes the association of vesicles with lung cells. Taken together, these results suggest that P. aeruginosa vesicles can interact with and be internalized by lung epithelial cells and contribute to the inflammatory response during infection.

  18. Commercial cow milk contains physically stable extracellular vesicles expressing immunoregulatory TGF-β.

    Science.gov (United States)

    Pieters, Bartijn C H; Arntz, Onno J; Bennink, Miranda B; Broeren, Mathijs G A; van Caam, Arjan P M; Koenders, Marije I; van Lent, Peter L E M; van den Berg, Wim B; de Vries, Marieke; van der Kraan, Peter M; van de Loo, Fons A J

    2015-01-01

    Extracellular vesicles, including exosomes, have been identified in all biological fluids and rediscovered as an important part of the intercellular communication. Breast milk also contains extracellular vesicles and the proposed biological function is to enhance the antimicrobial defense in newborns. It is, however, unknown whether extracellular vesicles are still present in commercial milk and, more importantly, whether they retained their bioactivity. Here, we characterize the extracellular vesicles present in semi-skimmed cow milk available for consumers and study their effect on T cells. Extracellular vesicles from commercial milk were isolated and characterized. Milk-derived extracellular vesicles contained several immunomodulating miRNAs and membrane protein CD63, characteristics of exosomes. In contrast to RAW 267.4 derived extracellular vesicles the milk-derived extracellular vesicles were extremely stable under degrading conditions, including low pH, boiling and freezing. Milk-derived extracellular vesicles were easily taken up by murine macrophages in vitro. Furthermore, we found that they can facilitate T cell differentiation towards the pathogenic Th17 lineage. Using a (CAGA)12-luc reporter assay we showed that these extracellular vesicles carried bioactive TGF-β, and that anti-TGF-β antibodies blocked Th17 differentiation. Our findings show that commercial milk contains stable extracellular vesicles, including exosomes, and carry immunoregulatory cargo. These data suggest that the extracellular vesicles present in commercial cow milk remains intact in the gastrointestinal tract and exert an immunoregulatory effect.

  19. Molecular Recognition of Vesicles : Host-Guest Interactions Combined with Specific Dimerization of Zwitterions

    NARCIS (Netherlands)

    Voskuhl, Jens; Fenske, Tassilo; Stuart, Marc C. A.; Wibbeling, Birgit; Schmuck, Carsten; Ravoo, Bart Jan

    2010-01-01

    The aggregation of beta-cyclodextrin vesicles can be induced by an adamantyl-substituted zwitterionic guanidiniocarbonylpyrrole carboxylate guest molecule (1). Upon addition of 1 to the cyclodextrin vesicles at neutral pH, the vesicles aggregate (but do not fuse), as shown by using UV/Vis and

  20. The function of vesicles in the actinomycete Frankia

    NARCIS (Netherlands)

    Meesters, T.

    1988-01-01

    The actinomycete Frankia is a symbiotic nitrogen fixer, living in root nodules of many non-leguminous plants. A typical characteristic of this endophytic organism is the formation of specialized swollen cell structures, called vesicles. Frankia

  1. Ultrasound-guided seminal vesicle biopsies in prostate cancer

    NARCIS (Netherlands)

    Wymenga, LFA; Duisterwinkel, FJ; Groenier, K; Mensink, HJA

    2000-01-01

    Invasion of prostatic adenocarcinoma into the seminal vesicles (SV) is generally accepted as an index of poor prognosis. The pre-operative identification of SV invasion is an important element in staging since it may alter subsequent treatment decisions. We studied the possibility of diagnosing SV

  2. Reconciling Ligase Ribozyme Activity with Fatty Acid Vesicle Stability

    Directory of Open Access Journals (Sweden)

    Fabrizio Anella

    2014-12-01

    Full Text Available The “RNA world” and the “Lipid world” theories for the origin of cellular life are often considered incompatible due to the differences in the environmental conditions at which they can emerge. One obstacle resides in the conflicting requirements for divalent metal ions, in particular Mg2+, with respect to optimal ribozyme activity, fatty acid vesicle stability and protection against RNA strand cleavage. Here, we report on the activity of a short L1 ligase ribozyme in the presence of myristoleic acid (MA vesicles at varying concentrations of Mg2+. The ligation rate is significantly lower at low-Mg2+ conditions. However, the loss of activity is overcompensated by the increased stability of RNA leading to a larger amount of intact ligated substrate after long reaction periods. Combining RNA ligation assays with fatty acid vesicles we found that MA vesicles made of 5 mM amphiphile are stable and do not impair ligase ribozyme activity in the presence of approximately 2 mM Mg2+. These results provide a scenario in which catalytic RNA and primordial membrane assembly can coexist in the same environment.

  3. Swinging of two-domains vesicles in shear flow

    Science.gov (United States)

    Viallat, Annie; Tusch, Simon; Khelloufi, Kamel; Leonetti, Marc

    2014-11-01

    Giant lipid vesicles and red blood cells in shear flow at low shear rates tank tread (TT) at small viscosity ratio between the inner particle volume and the external fluid, and flip or tumble (T) at large viscosity ratio. The phase diagram of motion of red blood cells is however much more complex. Swinging superimposes to TT, cells wobble and roll rather than tumble with increasing shear rate and present a shear-rate driven transition between TT to T. These features are attributed to the shear elasticity and the non spherical stress-free shape of the cell membrane, which stores shear elastic energy as a function of the relative position of its elements. We have created vesicles with a phase diagram of motion comparable to that of red blood cells by preparing membranes with two lipids and cholesterol. These membranes present two domains separated by a contact line. The line has a tension energy that depends on its relative position on the vesicle. Similarly to red blood cells, two-domains vesicles swing and wobble. An analytical model where line tension energy is added to the Keller and Skalak's model fits our experimental data without any adjustable parameter. Our experiments and model shed light on the motion of deformable particles in shear flow.

  4. Dimensional characterization of extracellular vesicles using atomic force microscopy

    NARCIS (Netherlands)

    Sebaihi, N.; de Boeck, B.; Yuana, Y.; Nieuwland, R.; Petry, J.

    2017-01-01

    Extracellular vesicles (EV) are small biological entities released from cells into body fluids. EV are recognized as mediators in intercellular communication and influence important physiological processes. It has been shown that the concentration and composition of EV in body fluids may differ from

  5. Calcium transport in vesicles energized by cytochrome oxidase

    Energy Technology Data Exchange (ETDEWEB)

    Rosier, Randy N. [Univ. of Rochester, NY (United States)

    1979-01-01

    Experiments on the reconstitution of cytochrome oxidase into phospholipid vesicles were carried out using techniques of selectivity energizing the suspensions with ascorbate and cytochrome c or ascorbate, PMS, and internally trapped cytochrome c. It was found that the K+ selective ionophore valinomycin stimulated the rate of respiration of cytochrome oxidase vesicles regardless of the direction of the K+ flux across the vesicle membranes. The stimulation occurred in the presence of protonophoric uncouplers and in the complete absence of potassium or in detergent-lysed suspensions. Gramicidin had similar effects and it was determined that the ionophores acted by specific interaction with cytochrome oxidase rather than by the previously assumed collapse of membrane potentials. When hydrophobic proteins and appropriate coupling factors were incorporated into the cytochrome oxidase, vesicles phosphorylation of ADP could be coupled to the oxidation reaction of cytochrome oxidase. Relatively low P:O, representing poor coupling of the system, were problematical and precluded measurements of protonmotive force. However the system was used to study ion translocation.

  6. A Pathogenic Potential of Acinetobacter baumannii-Derived Membrane Vesicles

    Directory of Open Access Journals (Sweden)

    Jong Suk Jin

    2011-12-01

    Full Text Available Acinetobacter baumannii secretes outer membrane vesicles (OMVs. A. baumannii OMVs deliver many virulence factors to host cells and then induce cytotoxicity and innate immune response. OMVs secreted from bacteria contribute directly to host pathology during A. baumannii infection.

  7. Patterns of Surface Immobilized Block Copolymer Vesicle Nanoreactors

    NARCIS (Netherlands)

    Chen, Qi; de Groot, G.W.; Schönherr, Holger; Vancso, Gyula J.

    2011-01-01

    The immobilization and positioning of ultra small reaction vessels on solid supports open new pathways in applications such as lab-on-a-chip, sensors, microanalyses and microreactors. In our work block copolymer vesicles made from polystyrene-block-polyacrylic acid (PS-b-PAA) were immobilized from

  8. Cdk5 is essential for synaptic vesicle endocytosis

    DEFF Research Database (Denmark)

    Tan, Timothy C; Valova, Valentina A; Malladi, Chandra S

    2003-01-01

    Synaptic vesicle endocytosis (SVE) is triggered by calcineurin-mediated dephosphorylation of the dephosphin proteins. SVE is maintained by the subsequent rephosphorylation of the dephosphins by unidentified protein kinases. Here, we show that cyclin-dependent kinase 5 (Cdk5) phosphorylates dynamin...

  9. Response of midpiece vesicles on human sperm to osmotic stress

    DEFF Research Database (Denmark)

    Abraham-Peskir, Joanna V; Chantler, Eric; Uggerhøj, Erik

    2002-01-01

    BACKGROUND: We investigated the osmotic response of midpiece vesicles (MPV) on human sperm. METHODS: Light microscopy, transmission X-ray microscopy and computer-aided semen analysis was used to investigate sperm in normozoospermic semen from healthy donors, separated from semen and suspended...

  10. Packing states of multilamellar vesicles in a nonionic surfactant system

    DEFF Research Database (Denmark)

    Le, T.D.; Olsson, U.; Mortensen, K.

    2001-01-01

    under shear. Here, we focused only in the MLV region, L-alpha(*), of a temperature sensitive surfactant system (C12E4-water) to investigate the packing of multilamellar vesicles as a function of temperature under constant shear. Two sets of temperature scan experiments were performed in the L...

  11. Intermedin inhibits norepinephrine-induced contraction of rat seminal vesicle

    Directory of Open Access Journals (Sweden)

    P.F. Wong

    2014-09-01

    Conclusion: The results demonstrated that the inhibitory action of IMD on NE-induced seminal vesicle contraction was mediated via the ADM receptor(s and the nitric oxide production pathway, partially by the IMD receptor, but not by the CGRP receptor and the cAMP-PKA pathway.

  12. Glucose-oxidase based self-destructing polymeric vesicles

    NARCIS (Netherlands)

    Napoli, A.; Boerakker, M.J.; Tirelli, N.; Nolte, R.J.M.; Sommerdijk, N.A.J.M.; Hubbell, J.A.

    2004-01-01

    We have designed oxidation-responsive vesicles from synthetic amphiphilic block copolymers ("polymersomes") of ethylene glycol and propylene sulfide. Thioethers in the hydrophobic poly(propylene sulfide) block are converted into the more hydrophilic sulfoxides and sulfones upon exposure to an

  13. Proteomic analysis of cerebrospinal fluid extracellular vesicles: A comprehensive dataset

    NARCIS (Netherlands)

    Chiasserini, D.; van Weering, J.R.T.; Piersma, S.R.; Pham, T.V.; Malekzadeh, A.; Teunissen, C.E.; de Wit, H.; Jimenez, C.R.

    2014-01-01

    Extracellular vesicles (EVs) are present in human cerebrospinal fluid (CSF), yet little is known about their protein composition. The aim of this study is to provide a comprehensive analysis of the proteome of CSF EVs by electron microscopy and high resolution tandem mass spectrometry (MS/MS) in

  14. Cell-derived vesicles exposing coagulant tissue factor in saliva

    NARCIS (Netherlands)

    Berckmans, René J.; Sturk, Auguste; van Tienen, Laurens M.; Schaap, Marianne C. L.; Nieuwland, Rienk

    2011-01-01

    On vascular damage, coagulation is initiated by extravascular tissue factor (TF). Intravascular TF, which is present on circulating cell-derived vesicles, is non-coagulant under physiologic conditions but prothrombotic under pathologic conditions. Human saliva triggers coagulation, but the mechanism

  15. Cell-derived vesicles exposing coagulant tissue factor in saliva.

    Science.gov (United States)

    Berckmans, René J; Sturk, Auguste; van Tienen, Laurens M; Schaap, Marianne C L; Nieuwland, Rienk

    2011-03-17

    On vascular damage, coagulation is initiated by extravascular tissue factor (TF). Intravascular TF, which is present on circulating cell-derived vesicles, is noncoagulant under physiologic conditions but prothrombotic under pathologic conditions. Human saliva triggers coagulation, but the mechanism and physiologic relevance are unknown. Because saliva is known to contain TF, we hypothesized that this TF may also be associated with cell-derived vesicles to facilitate coagulation when saliva directly contacts blood. The saliva-induced shortening of the clotting time of autologous plasma and whole blood from healthy subjects (n = 10) proved TF-dependent. This TF was associated with various types of cell-derived vesicles, including microparticles and exosomes. The physiologic function was shown by adding saliva to human pericardial wound blood collected from patients undergoing cardiac surgery. Addition of saliva shortened the clotting time from 300 ± 96 to 186 ± 24 seconds (P = .03). Our results show that saliva triggers coagulation, thereby reducing blood loss and the risk of pathogens entering the blood. We postulate that our reflex to lick a wound may be a mechanism to enable TF-exposing vesicles, present in saliva, to aid in the coagulation process and thus protect the organism from entering pathogens. This unique compartmentalization may be highly conserved because also animals lick their wounds.

  16. Extracellular vesicles in human follicular fluid do not promote coagulation

    NARCIS (Netherlands)

    Franz, Cordula; Böing, Anita N.; Montag, Markus; Strowitzki, Thomas; Markert, Udo R.; Mastenbroek, Sebastiaan; Nieuwland, Rienk; Toth, Bettina

    2016-01-01

    Body fluids contain extracellular vesicles expressing tissue factor on their surface and serve as an additional trigger for coagulation. During the menstrual cycle ovarian tissue restoration is mandatory and it is unknown whether follicular fluid might provide procoagulant substances. Within an

  17. The role of extracellular vesicles in neurodegenerative diseases.

    Science.gov (United States)

    Quek, Camelia; Hill, Andrew F

    2017-02-19

    Extracellular vesicles, including exosomes, are small membranous vesicles released from many biotypes, contributing to the disease progression and spreading. These extracellular vesicles provide an important mode of cell-to-cell communication by delivering proteins, lipids and RNA to target cells. Exosomes are found associated with neurodegenerative diseases, which are characterised by progressive degeneration of neurons and often associated with misfolded protein. The common diseases include Parkinson's disease (PD), Alzheimer's diseases (AD), amyotrophic lateral sclerosis (ALS), and the prion diseases. Of all neurodegenerative diseases, prion diseases are classified as the distinctive group owing to its transmissible and infectious nature of misfolded prion protein. The infectious prion particles have been demonstrated to be present in exosomes to spread prion infectivity within cells. Similarly, misfolded proteins involved in other neurodegenerative diseases such as Amyloid-β and tau in AD, α-synuclein in PD, and superoxide dismutase 1 in ALS have been demonstrated to exploit exosomes for induced spreading of misfolded proteins in a prion-like mechanism. Furthermore, RNA molecules can be taken up by the recipient cells as cargo in exosomes. These RNAs can module the expression of the target genes by repressing or inhibiting protein translation. Here we review the role of exosomes in prion diseases and other common neurodegenerative diseases, and discuss the potential of these vesicles for disease pathogenesis. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. Transmembrane topology of the acetylcholine receptor examined in reconstituted vesicles

    Energy Technology Data Exchange (ETDEWEB)

    McCrea, P.D.

    1987-01-01

    Each of the five acetylcholine receptor (AChR) subunits, ..cap alpha../sub 2/..beta..-..gamma..delta, is believed to have the same number of transmembrane crossing and to share the same general folding pattern. AChR isolated from the electric organ of electric fish is predominantly dimeric. We have used this bridge as a marker for the C-terminus of the delta subunit, and presumably that of the other subunits in addition. The disulfide's accessibility to hydrophilic reductants, principally glutathione (GSH), was tested in a reconstituted vesicle system. The reduction of the delta-delta desulfide, as evidenced by the transition of AChrR dimers to monomers, was quantitatively monitored on velocity sedimentation sucrose gradients. Alternatively, the reduction of delta/sub 2/ to delta was followed by employing non-reducing SDS-PAGE. Reductants such as GSH were able to access the bridge in intact right-side-out vesicles. No acceleration of this process was evident when the vesicles were disrupted by freeze-thaw or by detergents. Control experiments which determined the rate of reduction of entrapped diphtheria toxin, or that of /sup 3/H-GSH efflux, demonstrated that intact reconstituted vesicles provide an adequate permeability barrier to GSH access of their intravesicular space.

  19. Polymeric vesicles: from drug carriers to nanoreactors and artificial organelles.

    Science.gov (United States)

    Tanner, Pascal; Baumann, Patric; Enea, Ramona; Onaca, Ozana; Palivan, Cornelia; Meier, Wolfgang

    2011-10-18

    One strategy in modern medicine is the development of new platforms that combine multifunctional compounds with stable, safe carriers in patient-oriented therapeutic strategies. The simultaneous detection and treatment of pathological events through interactions manipulated at the molecular level offer treatment strategies that can decrease side effects resulting from conventional therapeutic approaches. Several types of nanocarriers have been proposed for biomedical purposes, including inorganic nanoparticles, lipid aggregates, including liposomes, and synthetic polymeric systems, such as vesicles, micelles, or nanotubes. Polymeric vesicles--structures similar to lipid vesicles but created using synthetic block copolymers--represent an excellent candidate for new nanocarriers for medical applications. These structures are more stable than liposomes but retain their low immunogenicity. Significant efforts have been made to improve the size, membrane flexibility, and permeability of polymeric vesicles and to enhance their target specificity. The optimization of these properties will allow researchers to design smart compartments that can co-encapsulate sensitive molecules, such as RNA, enzymes, and proteins, and their membranes allow insertion of membrane proteins rather than simply serving as passive carriers. In this Account, we illustrate the advances that are shifting these molecular systems from simple polymeric carriers to smart-complex protein-polymer assemblies, such as nanoreactors or synthetic organelles. Polymeric vesicles generated by the self-assembly of amphiphilic copolymers (polymersomes) offer the advantage of simultaneous encapsulation of hydrophilic compounds in their aqueous cavities and the insertion of fragile, hydrophobic compounds in their membranes. This strategy has permitted us and others to design and develop new systems such as nanoreactors and artificial organelles in which active compounds are simultaneously protected and allowed to

  20. Sodium channels and pain.

    Science.gov (United States)

    Habib, Abdella M; Wood, John N; Cox, James J

    2015-01-01

    Human and mouse genetic studies have led to significant advances in our understanding of the role of voltage-gated sodium channels in pain pathways. In this chapter, we focus on Nav1.7, Nav1.8, Nav1.9 and Nav1.3 and describe the insights gained from the detailed analyses of global and conditional transgenic Nav knockout mice in terms of pain behaviour. The spectrum of human disorders caused by mutations in these channels is also outlined, concluding with a summary of recent progress in the development of selective Nav1.7 inhibitors for the treatment of pain.

  1. Reconstitution of lipid vesicles associated with HVJ (Sendai virus) sikes. Purification and some properties of vesicles containing nontoxic fragment A of diphtheria toxin

    Science.gov (United States)

    1979-01-01

    A mixture of HVJ (Sendai virus) spike proteins, the nontoxic fragment A of diphtheria toxin, lecithin, and cholesterol was solubilized in sucrose solution containing a nonionic neutral detergent. The liposomal vesicles which formed on removal of the detergent by dialysis were purified by gel filtration and centrifugation on a sucrose gradient. The resulting purified vesicles had hemagglutinating activity, hemolytic activity and, after solubilization, the enzymic activity of fragment A. The vesicles had no cell fusion activity. Electron microscopy showed that both the outside and inside of membranes of the vesicles were associated with the spikes. When the vesicles were freeze- fractured, no large aggregates of particles were seen on either face. Such fragment A-containing lipid vesicles (liposomes) with HVJ spikes bound to mamalian cell membrane and released their fragment A into the cytoplasm causing cell death. Neither fragment A-containing liposomes without spikes nor empty liposomes with spikes were toxic. PMID:217880

  2. Enhanced transdermal delivery of diclofenac sodium via conventional liposomes, ethosomes, and transfersomes.

    Science.gov (United States)

    Ghanbarzadeh, Saeed; Arami, Sanam

    2013-01-01

    The aim of this study was to improve the transdermal permeation of Diclofenac sodium, a poorly water-soluble drug, employing conventional liposomes, ethosomes, and transfersomes. The prepared formulations had been characterized for the loaded drug amount and vesicle size. The prepared vesicular systems were incorporated into 1% Carbopol 914 gel, and a survey of in vitro drug release and drug retention into rat skin has been done on them using a modified Franz diffusion cell. The cumulative amount of drug permeated after 24 h, flux, and permeability coefficient were assessed. Stability studies were performed for three months. The size of vesicles ranged from 145 to 202 nm, and the encapsulation efficiency of the Diclofenac sodium was obtained between 42.61% and 51.72%. The transfersomes and ethosomes provided a significantly higher amount of cumulative permeation, steady state flux, permeability coefficient, and residual drug into skin compared to the conventional liposomes, conventional gel, or hydroethanolic solution. The in vitro release data of all vesicular systems were well fit into Higuchi model (RSD > 0.99). Stability tests indicated that the vesicular formulations were stable over three months. Results revealed that both ethosome and transfersome formulations can act as drug reservoir in skin and extend the pharmacologic effects of Diclofenac sodium.

  3. Enhanced Transdermal Delivery of Diclofenac Sodium via Conventional Liposomes, Ethosomes, and Transfersomes

    Directory of Open Access Journals (Sweden)

    Saeed Ghanbarzadeh

    2013-01-01

    Full Text Available The aim of this study was to improve the transdermal permeation of Diclofenac sodium, a poorly water-soluble drug, employing conventional liposomes, ethosomes, and transfersomes. The prepared formulations had been characterized for the loaded drug amount and vesicle size. The prepared vesicular systems were incorporated into 1% Carbopol 914 gel, and a survey of in vitro drug release and drug retention into rat skin has been done on them using a modified Franz diffusion cell. The cumulative amount of drug permeated after 24 h, flux, and permeability coefficient were assessed. Stability studies were performed for three months. The size of vesicles ranged from 145 to 202 nm, and the encapsulation efficiency of the Diclofenac sodium was obtained between 42.61% and 51.72%. The transfersomes and ethosomes provided a significantly higher amount of cumulative permeation, steady state flux, permeability coefficient, and residual drug into skin compared to the conventional liposomes, conventional gel, or hydroethanolic solution. The in vitro release data of all vesicular systems were well fit into Higuchi model (RSD > 0.99. Stability tests indicated that the vesicular formulations were stable over three months. Results revealed that both ethosome and transfersome formulations can act as drug reservoir in skin and extend the pharmacologic effects of Diclofenac sodium.

  4. S-Layered Aneurinibacillus and Bacillus spp. Are Susceptible to the Lytic Action of Pseudomonas aeruginosa Membrane Vesicles

    Science.gov (United States)

    Kadurugamuwa, J. L.; Mayer, A.; Messner, P.; Sára, M.; Sleytr, U. B.; Beveridge, T. J.

    1998-01-01

    When S-layered strains of Bacillus stearothermophilus and Aneurinibacillus thermoaerophilus, possessing S-layers of different lattice type and lattice constant as well as S-(glyco)protein chemistry, and isogenic S-layerless variants were subjected to membrane vesicles (MVs) from P. aeruginosa during plaque assays on plates or CFU measurements on cell suspensions, all bacterial types lysed. Electron microscopy of negative stains, thin sections, and immunogold-labelled MV preparations revealed that the vesicles adhered to all bacterial surfaces, broke open, and digested the underlying peptidoglycan-containing cell wall of all cell types. Reassembled S-layer did not appear to be affected by MVs, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis showed that the S-(glyco)proteins remained intact. meso-Diaminopimelic acid, as a peptidoglycan breakdown product, was found in all culture supernatants after MV attack. These results suggest that even though MVs are much larger than the channels which penetrate these proteinaceous arrays, S-layers on gram-positive bacteria do not form a defensive barrier against the lytic action of MVs. The primary mode of attack is by the liberation from the MVs of a peptidoglycan hydrolase, which penetrates through the S-layer to digest the underlying peptidoglycan-containing cell wall. The S-layer is not affected by MV protease. PMID:9573179

  5. Reconstituted proteolipid vesicles prepared from Mycoplasma fermentans membranes are able to bind and fuse with Molt-3 cells.

    Science.gov (United States)

    Rechnitzer, Hagai; Rottem, Shlomo

    2006-10-01

    We describe and characterize reconstituted proteolipid vesicles (rPLV) prepared from solubilized Mycoplasma fermentans membranes and studied their binding to and fusion with host Molt-3 cells. The rPLV were prepared following membrane solubilization by Triton X-100 and detergent removal by SM-2 resin beads. The vesicles thus obtained had a rather uniform diameter of about 1 microm and were sealed as monitored by measuring in an assay that measures the quenching by sodium dithionite of a hydrophobic fluorescent probe incorporated into the rPLV membrane. The rPLV adhered to Molt-3 cells and, based on measurements of lipid mixing, fused with the host cells at a similar rate and to about the same extent as intact M. fermentans. Preliminary experiments showed that a chimeric protein, GnRH-PE66, could be encapsulated within these rPLV, opening the way to develop a system for the transfer of high-molecular weight soluble molecules, encapsulated in the rPLV, to target eukaryotic cells.

  6. Mechanistic studies of sodium pump.

    Science.gov (United States)

    Faller, Larry D

    2008-08-01

    Sodium pump was the first ion pump discovered. A member of the family of active transporters that catalyze adenosine 5'-triphosphate hydrolysis by forming a phosphorylated enzyme intermediate, sodium pump couples the energy released to unequal countertransport of sodium and potassium ions. The ion gradient generated by the pump is important for a variety of secondary physiological processes ranging from metabolite transport to electrical excitation of nerve and muscle. Selected experiments relating structure to function are reviewed.

  7. Sodium channelopathies and pain.

    Science.gov (United States)

    Lampert, Angelika; O'Reilly, Andrias O; Reeh, Peter; Leffler, Andreas

    2010-07-01

    Chronic pain often represents a severe, debilitating condition. Up to 10% of the worldwide population are affected, and many patients are poorly responsive to current treatment strategies. Nociceptors detect noxious conditions to produce the sensation of pain, and this signal is conveyed to the CNS by means of action potentials. The fast upstroke of action potentials is mediated by voltage-gated sodium channels, of which nine pore-forming alpha-subunits (Nav1.1-1.9) have been identified. Heterogeneous functional properties and distinct expression patterns denote specialized functions of each subunit. The Nav1.7 and Nav1.8 subunits have emerged as key molecules involved in peripheral pain processing and in the development of an increased pain sensitivity associated with inflammation and tissue injury. Several mutations in the SCN9A gene encoding for Nav1.7 have been identified as important cellular substrates for different heritable pain syndromes. This review aims to cover recent progress on our understanding of how biophysical properties of mutant Nav1.7 translate into an aberrant electrogenesis of nociceptors. We also recapitulate the role of Nav1.8 for peripheral pain processing and of additional sodium channelopathies which have been linked to disorders with pain as a significant component.

  8. Arabinogalactan Proteins Are Involved in Salt-Adaptation and Vesicle Trafficking in Tobacco by-2 Cell Cultures

    Directory of Open Access Journals (Sweden)

    Enrique Olmos

    2017-06-01

    Full Text Available Arabinogalactan proteins (AGPs are a highly diverse family of glycoproteins that are commonly found in most plant species. However, little is known about the physiological and molecular mechanisms of their function. AGPs are involved in different biological processes such as cell differentiation, cell expansion, tissue development and somatic embryogenesis. AGPs are also involved in abiotic stress response such as salinity modulating cell wall expansion. In this study, we describe how salt-adaptation in tobacco BY-2 cell cultures induces important changes in arabinogalactan proteins distribution and contents. Using the immuno-dot blot technique with different anti-AGP antibodies (JIM13, JIM15, and others, we observed that AGPs were highly accumulated in the culture medium of salt-adapted tobacco cells, probably due to the action of phospholipases. We located these AGP epitopes using immunogold labeling in the cytoplasm associated to the endoplasmic reticulum, the golgi apparatus, and vesicles, plasma membrane and tonoplast. Our results show that salt-adaptation induced a significant reduction of the cytoplasm, plasma membrane and tonoplast content of these epitopes. Yariv reagent was added to the control and salt-adapted tobacco cell cultures, leading to cell death induction in control cells but not in salt-adapted cells. Ultrastructural and immunogold labeling revealed that cell death induced by Yariv reagent in control cells was due to the interaction of Yariv reagent with the AGPs linked to the plasma membranes. Finally, we propose a new function of AGPs as a possible sodium carrier through the mechanism of vesicle trafficking from the apoplast to the vacuoles in salt-adapted tobacco BY-2 cells. This mechanism may contribute to sodium homeostasis during salt-adaptation to high saline concentrations.

  9. Genetically controlled fusion, exocytosis and fission of artificial vesicles-a roadmap

    DEFF Research Database (Denmark)

    Bönzli, Eva; Hadorn, Maik; de Lucrezia, Davide

    2011-01-01

    were shown to fuse if a special class of viral proteins, termed fusogenic peptides, were added to the external medium (Nomura et al. 2004). In the present work, we intend to develop genetically controlled fusion, fission and exocytosis of vesicles by the synthesis of peptides within vesicles. First, we...... enclosed synthesized peptides in vesicles to induce in a next step fusion of adjacent vesicles, fission and exocytosis of nested vesicles. Second, we will replace the peptides by an enclosed cell-free expression system to internally synthesize fusion peptides. To control the gene expression, different...

  10. Role of extracellular vesicles in de novo mineralization: an additional novel mechanism of cardiovascular calcification.

    Science.gov (United States)

    New, Sophie E P; Aikawa, Elena

    2013-08-01

    Extracellular vesicles are membrane micro/nanovesicles secreted by many cell types into the circulation and the extracellular milieu in physiological and pathological conditions. Evidence suggests that extracellular vesicles, known as matrix vesicles, play a role in the mineralization of skeletal tissue, but emerging ultrastructural and in vitro studies have demonstrated their contribution to cardiovascular calcification as well. Cells involved in the progression of cardiovascular calcification release active vesicles capable of nucleating hydroxyapatite on their membranes. This review discusses the role of extracellular vesicles in cardiovascular calcification and elaborates on this additional mechanism of calcification as an alternative pathway to the currently accepted mechanism of biomineralization via osteogenic differentiation.

  11. Proteomic Analysis of Blood Extracellular Vesicles in Cardiovascular Disease by LC-MS/MS Analysis.

    Science.gov (United States)

    Baldan-Martin, Montserrat; de la Cuesta, Fernando; Alvarez-Llamas, Gloria; Ruiz-Hurtado, Gema; Ruilope, Luis M; Barderas, Maria G

    2017-01-01

    Extracellular vesicles are membrane vesicles related to cell communication. These vesicles consist of proteins, RNA, and microRNA and are an interesting and important tool to understand the processes taking place in the secreting cell, especially in diseases in which its release is often enhanced. The used of blood extracellular vesicles in cardiovascular disease as a low invasive, easily accessible source of circulating markers could give us important information related to pathological process even more with the use of proteomic analysis. In this chapter, we describe a protocol to isolate and proteomic analyze extracellular vesicles from blood associated with cardiovascular disease.

  12. Minimal experimental requirements for definition of extracellular vesicles and their functions: a position statement from the International Society for Extracellular Vesicles

    Science.gov (United States)

    Hill, Andrew F.; Hochberg, Fred; Buzás, Edit I.; Di Vizio, Dolores; Gardiner, Christopher; Gho, Yong Song; Kurochkin, Igor V.; Mathivanan, Suresh; Quesenberry, Peter; Sahoo, Susmita; Tahara, Hidetoshi; Wauben, Marca H.; Witwer, Kenneth W.; Théry, Clotilde

    2014-01-01

    Secreted membrane-enclosed vesicles, collectively called extracellular vesicles (EVs), which include exosomes, ectosomes, microvesicles, microparticles, apoptotic bodies and other EV subsets, encompass a very rapidly growing scientific field in biology and medicine. Importantly, it is currently technically challenging to obtain a totally pure EV fraction free from non-vesicular components for functional studies, and therefore there is a need to establish guidelines for analyses of these vesicles and reporting of scientific studies on EV biology. Here, the International Society for Extracellular Vesicles (ISEV) provides researchers with a minimal set of biochemical, biophysical and functional standards that should be used to attribute any specific biological cargo or functions to EVs. PMID:25536934

  13. Effects of topical flurbiprofen sodium, diclofenac sodium, ketorolac ...

    African Journals Online (AJOL)

    To evaluate corneal sensitivity by using the Cochet-Bonnet® esthesiometer in normal canine eyes at different time points following instillation of three different topical non-steroidal anti-inflammatory drugs (flurbiprofen sodium 0.03%, diclofenac sodium 0.1% and ketorolac tromethamine 0.5%) and benzalkonium chloride ...

  14. Contribution of sodium dodecyl sulphate and sodium lauric acid in ...

    Indian Academy of Sciences (India)

    Contribution of sodium dodecyl sulphate and sodium lauric acid in the one-pot synthesis of intercalated ZnAl-layered double hydroxides. Fengzhu Lv Zilin Meng Penggang Li Yihe Zhang Guocheng Lv Qian Zhang Zhilei Zhang. Volume 38 Issue 4 August 2015 pp 1079-1085. Fulltext. Click here to view fulltext PDF.

  15. Solute partitioning in aqueous surfactant assemblies: comparison of hydrophobic-hydrophilic interactions in micelles, alcohol-swollen micelles, microemulsions, and synthetic vesicles

    Energy Technology Data Exchange (ETDEWEB)

    Russell, J.C.; Whitten, D.G.

    1982-11-03

    The structures of anionic assemblies including sodium lauryl sulfate (SLS) micelles, alcohol-swollen SLS micelles, microemulsions, and vesicles of a mixture of dipalmitoyllecithin and dicetyl phosphate are investigated by using the ground-state complexation of a hydrophilic quencher (methyl viologen) with several hydrophobic fluorescent probes, including surfactant stilbenes and 1,4-diphenylbutadiene. In SLS micelles this complexation can be decreased nearly an order of magnitude by addition of 1-heptanol, indicating that the structure of the micelle can be adjusted from the highly open structure of the pure micelle to a much more closed structure in which hydrophobic solubilizates can be sequestered from hydrophilic reagents bound to the surface. The fluorescence quenching process in anionic vesicles is strongly dependent on temperature; at low temperatures quenching occurs, while at higher temperatures addition of methyl viologen appears to increase the stilbene fluorescence, indicating that the dicationic quencher binds to the vesicle surface, increasing the order of the system. These results indicate that the degree of organization of surfactant systems can be adjusted by simple changes in composition. 33 references.

  16. USE OF SODIUM ALUMINATE IN FOUNDRY PAINTS

    Directory of Open Access Journals (Sweden)

    O. S. Komarov

    2016-01-01

    Full Text Available Comparison of the properties of the casting paints based on sodium silicate and sodium aluminat, and sodium aluminat as an additive to the ink for the organic binder has shown that sodium aluminat provides a higher level of properties than sodium silicate and aluminat, in addition to an organic paint binder improves properties

  17. Astrocyte VAMP3 vesicles undergo Ca2+-independent cycling and modulate glutamate transporter trafficking

    Science.gov (United States)

    Li, Dongdong; Hérault, Karine; Zylbersztejn, Kathleen; Lauterbach, Marcel A; Guillon, Marc; Oheim, Martin; Ropert, Nicole

    2015-01-01

    Key points Mouse cortical astrocytes express VAMP3 but not VAMP2. VAMP3 vesicles undergo Ca2+-independent exo- and endocytotic cycling at the plasma membrane. VAMP3 vesicle traffic regulates the recycling of plasma membrane glutamate transporters. cAMP modulates VAMP3 vesicle cycling and glutamate uptake. Abstract Previous studies suggest that small synaptic-like vesicles in astrocytes carry vesicle-associated vSNARE proteins, VAMP3 (cellubrevin) and VAMP2 (synaptobrevin 2), both contributing to the Ca2+-regulated exocytosis of gliotransmitters, thereby modulating brain information processing. Here, using cortical astrocytes taken from VAMP2 and VAMP3 knock-out mice, we find that astrocytes express only VAMP3. The morphology and function of VAMP3 vesicles were studied in cultured astrocytes at single vesicle level with stimulated emission depletion (STED) and total internal reflection fluorescence (TIRF) microscopies. We show that VAMP3 antibodies label small diameter (∼80 nm) vesicles and that VAMP3 vesicles undergo Ca2+-independent exo-endocytosis. We also show that this pathway modulates the surface expression of plasma membrane glutamate transporters and the glutamate uptake by astrocytes. Finally, using pharmacological and optogenetic tools, we provide evidence suggesting that the cytosolic cAMP level influences astrocytic VAMP3 vesicle trafficking and glutamate transport. Our results suggest a new role for VAMP3 vesicles in astrocytes. PMID:25864578

  18. Lipid vesicle shape analysis from populations using light video microscopy and computer vision.

    Directory of Open Access Journals (Sweden)

    Jernej Zupanc

    Full Text Available We present a method for giant lipid vesicle shape analysis that combines manually guided large-scale video microscopy and computer vision algorithms to enable analyzing vesicle populations. The method retains the benefits of light microscopy and enables non-destructive analysis of vesicles from suspensions containing up to several thousands of lipid vesicles (1-50 µm in diameter. For each sample, image analysis was employed to extract data on vesicle quantity and size distributions of their projected diameters and isoperimetric quotients (measure of contour roundness. This process enables a comparison of samples from the same population over time, or the comparison of a treated population to a control. Although vesicles in suspensions are heterogeneous in sizes and shapes and have distinctively non-homogeneous distribution throughout the suspension, this method allows for the capture and analysis of repeatable vesicle samples that are representative of the population inspected.

  19. Vesicle dynamics in a confined Poiseuille flow: From steady state to chaos

    Science.gov (United States)

    Aouane, Othmane; Thiébaud, Marine; Benyoussef, Abdelilah; Wagner, Christian; Misbah, Chaouqi

    2014-09-01

    Red blood cells (RBCs) are the major component of blood, and the flow of blood is dictated by that of RBCs. We employ vesicles, which consist of closed bilayer membranes enclosing a fluid, as a model system to study the behavior of RBCs under a confined Poiseuille flow. We extensively explore two main parameters: (i) the degree of confinement of vesicles within the channel and (ii) the flow strength. Rich and complex dynamics for vesicles are revealed, ranging from steady-state shapes (in the form of parachute and slipper shapes) to chaotic dynamics of shape. Chaos occurs through a cascade of multiple periodic oscillations of the vesicle shape. We summarize our results in a phase diagram in the parameter plane (degree of confinement and flow strength). This finding highlights the level of complexity of a flowing vesicle in the small Reynolds number where the flow is laminar in the absence of vesicles and can be rendered turbulent due to elasticity of vesicles.

  20. Focus on Extracellular Vesicles: Therapeutic Potential of Stem Cell-Derived Extracellular Vesicles

    Directory of Open Access Journals (Sweden)

    Bin Zhang

    2016-02-01

    Full Text Available The intense research focus on stem and progenitor cells could be attributed to their differentiation potential to generate new cells to replace diseased or lost cells in many highly intractable degenerative diseases, such as Alzheimer disease, multiple sclerosis, and heart diseases. However, experimental and clinical studies have increasingly attributed the therapeutic efficacy of these cells to their secretion. While stem and progenitor cells secreted many therapeutic molecules, none of these molecules singly or in combination could recapitulate the functional effects of stem cell transplantations. Recently, it was reported that extracellular vesicles (EVs could recapitulate the therapeutic effects of stem cell transplantation. Based on the observations reported thus far, the prevailing hypothesis is that stem cell EVs exert their therapeutic effects by transferring biologically active molecules such as proteins, lipids, mRNA, and microRNA from the stem cells to injured or diseased cells. In this respect, stem cell EVs are similar to EVs from other cell types. They are both primarily vehicles for intercellular communication. Therefore, the differentiating factor is likely due to the composition of their cargo. The cargo of EVs from different cell types are known to include a common set of proteins and also proteins that reflect the cell source of the EVs and the physiological or pathological state of the cell source. Hence, elucidation of the stem cell EV cargo would provide an insight into the multiple physiological or biochemical changes necessary to affect the many reported stem cell-based therapeutic outcomes in a variety of experimental models and clinical trials.

  1. Comparative Study of Extracellular Vesicles from the Urine of Healthy Individuals and Prostate Cancer Patients.

    Science.gov (United States)

    Bryzgunova, Olga E; Zaripov, Marat M; Skvortsova, Tatyana E; Lekchnov, Evgeny A; Grigor'eva, Alina E; Zaporozhchenko, Ivan A; Morozkin, Evgeny S; Ryabchikova, Elena I; Yurchenko, Yuri B; Voitsitskiy, Vladimir E; Laktionov, Pavel P

    2016-01-01

    Recent studies suggest that extracellular vesicles may be the key to timely diagnosis and monitoring of genito-urological malignancies. In this study we investigated the composition and content of extracellular vesicles found in the urine of healthy donors and prostate cancer patients. Urine of 14 PCa patients and 20 healthy volunteers was clarified by low-speed centrifugation and total extracellular vesicles fraction was obtain by high-speed centrifugation. The exosome-enriched fraction was obtained by filtration of total extracellular vesicles through a 0.1 μm pore filter. Transmission electron microscopy showed that cell-free urine in both groups contained vesicles from 20 to 230 nm. Immunogold staining after ultrafiltration demonstrated that 95% and 90% of extracellular vesicles in healthy individuals and cancer patients, respectively, were exosomes. Protein, DNA and RNA concentrations as well as size distribution of extracellular vesicles in both fractions were analyzed. Only 75% of the total protein content of extracellular vesicles was associated with exosomes which amounted to 90-95% of all vesicles. Median DNA concentrations in total extracellular vesicles and exosome-enriched fractions were 18 pg/ml and 2.6 pg/ml urine, correspondingly. Urine extracellular vesicles carried a population of RNA molecules 25 nt to 200 nt in concentration of no more than 290 pg/ml of urine. Additionally, concentrations of miR-19b, miR-25, miR-125b, and miR-205 were quantified by qRT-PCR. MiRNAs were shown to be differently distributed between different fractions of extracellular vesicles. Detection of miR-19b versus miR-16 in total vesicles and exosome-enriched fractions achieved 100%/93% and 95%/79% specificity/sensitivity in distinguishing cancer patients from healthy individuals, respectively, demonstrating the diagnostic value of urine extracellular vesicles.

  2. MAA-1, a novel acyl-CoA-binding protein involved in endosomal vesicle transport in Caenorhabditis elegans

    DEFF Research Database (Denmark)

    Kobæk Larsen, Morten; Tuck, Simon; Færgeman, Nils J.

    2006-01-01

    The budding and fission of vesicles during membrane trafficking requires many proteins, including those that coat the vesicles, adaptor proteins that recruit components of the coat, and small GTPases that initiate vesicle formation. In addition, vesicle formation in vitro is promoted by the hydro...

  3. Three-component vesicle aggregation driven by adhesion interactions between Au nanoparticles and polydopamine-coated nanotubes.

    Science.gov (United States)

    Jin, Haibao; Zhou, Yongfeng; Huang, Wei; Zheng, Yongli; Zhu, Xinyuan; Yan, Deyue

    2014-06-11

    Large-scale and robust vesicle aggregates were obtained through molecular recognition among cell-sized polymer vesicles, carbon nanotubes and AuNPs, driven by adhesion interactions between Au and polydopamine. Vesicle fusion was effectively avoided in this three-component vesicle aggregation process.

  4. Synthesis of Non-Toxic Silica Particles Stabilized by Molecular Complex Oleic-Acid/Sodium Oleate

    Directory of Open Access Journals (Sweden)

    Catalin Ilie Spataru

    2016-11-01

    Full Text Available The present work is focused on the preparation of biocompatible silica particles from sodium silicate, stabilized by a vesicular system containing oleic acid (OLA and its alkaline salt (OLANa. Silica nanoparticles were generated by the partial neutralization of oleic acid (OLA, with the sodium cation present in the aqueous solutions of sodium silicate. At the molar ratio OLA/Na+ = 2:1, the molar ratio (OLA/OLANa = 1:1 required to form vesicles, in which the carboxyl and carboxylate groups have equal concentrations, was achieved. In order to obtain hydrophobically modified silica particles, octadecyltriethoxysilane (ODTES was added in a sodium silicate sol–gel mixture at different molar ratios. The interactions between the octadecyl groups from the modified silica and the oleyl chains from the OLA/OLANa stabilizing system were investigated via simultaneous thermogravimetry (TG and differential scanning calorimetry (DSC (TG-DSC analyses.A significant decrease in vaporization enthalpy and an increase in amount of ODTES were observed. Additionally, that the hydrophobic interaction between OLA and ODTES has a strong impact on the hybrids’ final morphology and on their textural characteristics was revealed. The highest hydrodynamic average diameter and the most negative ζ potential were recorded for the hybrid in which the ODTES/sodium silicate molar ratio was 1:5. The obtained mesoporous silica particles, stabilized by the OLA/OLANa vesicular system, may find application as carriers for hydrophobic bioactive molecules.

  5. Sodium pump localization in epithelia.

    Science.gov (United States)

    Bystriansky, Jason S; Kaplan, Jack H

    2007-12-01

    In epithelial cells, the sodium pump, in coordination with several other ion transporting proteins and channels, acts to regulate directional water and ion flux across the epithelial barrier. This function is dependant on the polarized localization of the sodium pump to a single plasma membrane domain. In most epithelial cell types the sodium pump is found in an exclusively basolateral position. Despite the clear importance of maintaining a polarized distribution of the sodium pump, surprisingly little is known about the specific mechanisms responsible for the targeting and trafficking of the sodium pump to the basolateral surface. We briefly discuss our current understanding of factors which may act to regulate the cellular distribution of the sodium pump, including the potential role of the sodium pump beta-subunit. Several previous, studies have suggested that the expression of the beta2 isoform (instead of beta1) may cause the apical localization of the sodium pump. This appeared to be confirmed by Wilson et al. Am J Pathol, 156: 253-268, 2000 who found that MDCK cells stably transfected with the beta2 subunit express the sodium pump at the apical surface. However, careful examination by Laughery et al.,Am J Physiol, 292: F1718-F1725, 2007, showed that the apical targeting of the pump was caused by the presence of butyrate in the cell growth media and was not due to the presence of the beta2 isoform. These findings are discussed below, along with potential explanations as to how butyrate may influence the polarity of the sodium pump in epithelial cells.

  6. Kinetic partitioning between aggregation and vesicle permeabilization by modified ADan

    DEFF Research Database (Denmark)

    Nesgaard, Lise W.; Vad, Brian; Christiansen, Gunna

    2009-01-01

    changed to serines to emulate the reduced peptide. SerADan aggregates rapidly at pH 5.0 and 7.5 in a series of conformational transitions to form beta-sheet rich fibril-like structures, which nevertheless do not bind amyloid-specific dyes, probably due to the absence of organized beta-sheet contacts....... Aggregation is prevented at neutral/acidic pH and low ionic strength by anionic lipid vesicles. These vesicles are permeabilized by monomeric SerADan assembling on the membrane to form stable beta-sheet structures which are different from the solution aggregates. In contrast, solution ageing of SerADan first......-fibrillar aggregates can assemble in a series of steps to form a hierarchy of higher-order assemblies, where rapid formation of stable local beta-sheet structure may prevent rearrangement to amyloid proper....

  7. Decoding the Secret of Cancer by Means of Extracellular Vesicles

    Directory of Open Access Journals (Sweden)

    Nobuyoshi Kosaka

    2016-02-01

    Full Text Available One of the recent outstanding developments in cancer biology is the emergence of extracellular vesicles (EVs. EVs, which are small membrane vesicles that contain proteins, mRNAs, long non-coding RNAs, and microRNAs (miRNAs, are secreted by a variety of cells and have been revealed to play an important role in intercellular communications. These molecules function in the recipient cells; this has brought new insight into cell-cell communication. Recent reports have shown that EVs contribute to cancer cell development, including tumor initiation, angiogenesis, immune surveillance, drug resistance, invasion, metastasis, maintenance of cancer stem cells, and EMT phenotype. In this review, I will summarize recent studies on EV-mediated miRNA transfer in cancer biology. Furthermore, I will also highlight the possibility of novel diagnostics and therapy using miRNAs in EVs against cancer.

  8. Decoding the Secret of Cancer by Means of Extracellular Vesicles

    Science.gov (United States)

    Kosaka, Nobuyoshi

    2016-01-01

    One of the recent outstanding developments in cancer biology is the emergence of extracellular vesicles (EVs). EVs, which are small membrane vesicles that contain proteins, mRNAs, long non-coding RNAs, and microRNAs (miRNAs), are secreted by a variety of cells and have been revealed to play an important role in intercellular communications. These molecules function in the recipient cells; this has brought new insight into cell-cell communication. Recent reports have shown that EVs contribute to cancer cell development, including tumor initiation, angiogenesis, immune surveillance, drug resistance, invasion, metastasis, maintenance of cancer stem cells, and EMT phenotype. In this review, I will summarize recent studies on EV-mediated miRNA transfer in cancer biology. Furthermore, I will also highlight the possibility of novel diagnostics and therapy using miRNAs in EVs against cancer. PMID:26861408

  9. Complex motions of vesicles and capsules in flow

    Science.gov (United States)

    Vlahovska, Petia; Young, Yuan-Nan; Misbah, Chaouqi

    2009-11-01

    Membrane-bound particles exhibit rich dynamics when placed in flow. For example, in simple shear flow, vesicles made of lipid bilayers tank-tread or tumble. Capsules and red blood cells also show oscillations in the tank-treading inclination angle, called swinging. This motion originates from membrane shear--elasticity and non--spherical unstressed shape. We develop an analytical theory that quantitatively describes the swinging dynamics. Our analysis takes into account that the membrane is deformable, incompressible, and resists bending and shearing. Analytical results for the shape evolution are derived by considering a nearly-spherical particle shape. The phase diagram is constructed and compared to previous models which assume fixed ellipsoidal shape. Dynamics in quadratic and time-dependent flows is also discussed. Floquet analysis is conducted to investigate the vesicle dynamics and conditions for chaotic shape and flow dynamics are established.

  10. Significance of Extracellular Vesicles: Pathobiological Roles in Disease.

    Science.gov (United States)

    Yamamoto, Seiji; Azuma, Erika; Muramatsu, Masashi; Hamashima, Takeru; Ishii, Yoko; Sasahara, Masakiyo

    2016-11-25

    Over the past decade, many studies have been conducted on extracellular vesicles (EVs) in the fields of basic and clinical research. EVs are small sized membranous vesicles generated from many type of cells upon activation by environmental stresses such as heat, hypoxia, and irradiation. EVs theoretically consist of microparticles/microvesicles, exosomes, and apoptotic bodies by different productive mechanisms. Clinically, EVs are observed in the blood stream of patients suffering from acute and chronic inflammation evoked by various diseases, and number of EVs in blood flow is often dependent on the inflammatory status and severity of the diseases. To date, it has been reported that small molecules such as RNAs and proteins are encapsulated in EVs; however, the functions of EVs are still unclear in the biological, pathological, and clinical aspects. In this review, we summarize and discuss the biogenesis-based classification, expected function, and pathobiological activities of EVs.

  11. Emerging roles of extracellular vesicles in cellular senescence and aging.

    Science.gov (United States)

    Takasugi, Masaki

    2018-02-01

    Cellular senescence is a cellular program that prevents the proliferation of cells at risk of neoplastic transformation. On the other hand, age-related accumulation of senescent cells promotes aging at least partially due to the senescence-associated secretory phenotype, whereby cells secrete high levels of inflammatory cytokines, chemokines, and matrix metalloproteinases. Emerging evidence, however, indicates that extracellular vesicles (EVs) are important mediators of the effects of senescent cells on their microenvironment. Senescent cells secrete more EphA2 and DNA via EVs, which can promote cancer cell proliferation and inflammation, respectively. Extracellular vesicles secreted from DNA-damaged cells can also affect telomere regulation. Furthermore, it has now become clear that EVs actually play important roles in many aspects of aging. This review is intended to summarize these recent progresses, with emphasis on relationships between cellular senescence and EVs. © 2018 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.

  12. Extracellular Vesicles as Therapeutic Agents in Systemic Lupus Erythematosus.

    Science.gov (United States)

    Perez-Hernandez, Javier; Redon, Josep; Cortes, Raquel

    2017-03-28

    Systemic lupus erythematosus (SLE) is a heterogeneous autoimmune disease that affects multiple organs. Currently, therapeutic molecules present adverse side effects and are only effective in some SLE patient subgroups. Extracellular vesicles (EV), including exosomes, microvesicles and apoptotic bodies, are released by most cell types, carry nucleic acids, proteins and lipids and play a crucial role in cell-to-cell communication. EVs can stimulate or suppress the immune responses depending on the context. In SLE, EVs can work as autoadjuvants, enhance immune complex formation and maintaining inflammation state. Over the last years, EVs derived from mesenchymal stem cells and antigen presenting cells have emerged as cell-free therapeutic agents to treat autoimmune and inflammatory diseases. In this review, we summarize the current therapeutic applications of extracellular vesicles to regulate immune responses and to ameliorate disease activity in SLE and other autoimmune disorders.

  13. Understanding the biosynthesis of platelets-derived extracellular vesicles.

    Science.gov (United States)

    Antwi-Baffour, Samuel; Adjei, Jonathan; Aryeh, Claudia; Kyeremeh, Ransford; Kyei, Foster; Seidu, Mahmood A

    2015-09-01

    Platelet-derived extracellular vesicles (PEVs) are described as sub-cellular vesicles released into circulation upon platelets shear stress, activation, injury, or apoptosis. They are considered as universal biomarkers in a wide range of physiological and pathological processes. They are of tremendous significance for the prediction, diagnosis, and observation of the therapeutic success of many diseases. Understanding their biosynthesis and therefore functional properties would contribute to a better understanding of the pathological mechanisms leading to various diseases in which their levels are raised and they are implicated. The review takes a critical look at the historical background of PEVs, their structural components, the mechanism of their formation, physiological, and exogenous stimuli inducing their release and their detection. It concludes by highlighting on the importance of undertaking in-depth studies into PEVs biosynthesis and subsequently gaining a better understanding of their biological role in general.

  14. Imaging and Quantification of Extracellular Vesicles by Transmission Electron Microscopy.

    Science.gov (United States)

    Linares, Romain; Tan, Sisareuth; Gounou, Céline; Brisson, Alain R

    2017-01-01

    Extracellular vesicles (EVs) are cell-derived vesicles that are present in blood and other body fluids. EVs raise major interest for their diverse physiopathological roles and their potential biomedical applications. However, the characterization and quantification of EVs constitute major challenges, mainly due to their small size and the lack of methods adapted for their study. Electron microscopy has made significant contributions to the EV field since their initial discovery. Here, we describe the use of two transmission electron microscopy (TEM) techniques for imaging and quantifying EVs. Cryo-TEM combined with receptor-specific gold labeling is applied to reveal the morphology, size, and phenotype of EVs, while their enumeration is achieved after high-speed sedimentation on EM grids.

  15. Curvature-Mediated Assembly of Janus Nanoparticles on Membrane Vesicles.

    Science.gov (United States)

    Bahrami, Amir Houshang; Weikl, Thomas R

    2018-01-08

    Besides direct particle-particle interactions, nanoparticles adsorbed to biomembranes experience indirect interactions that are mediated by the membrane curvature arising from particle adsorption. In this Letter, we show that the curvature-mediated interactions of adsorbed Janus particles depend on the initial curvature of the membrane prior to adsorption, that is, on whether the membrane initially bulges toward or away from the particles in our simulations. The curvature-mediated interaction can be strongly attractive for Janus particles adsorbed to the outside of a membrane vesicle, which initially bulges away from the particles. For Janus particles adsorbed to the vesicle inside, in contrast, the curvature-mediated interactions are repulsive. We find that the area fraction of the adhesive Janus particle surface is an important control parameter for the curvature-mediated interaction and assembly of the particles, besides the initial membrane curvature.

  16. Extracellular vesicles: small bricks for tissue repair/regeneration.

    Science.gov (United States)

    Taverna, Simona; Pucci, Marzia; Alessandro, Riccardo

    2017-02-01

    Extracellular vesicles (EVs) are nano-sized membrane vesicles involved in intercellular communication. EVs have pleiotropic actions in physiological and pathological conditions. The ability of EVs to transports proteins, drugs and nucleic acid, to target specific cells and to increase the stability of therapeutic cargo, make EVs interesting as new devices for the treatment of human disease. In a recently published issue of European journal of pharmaceutical sciences, Silva and colleagues reviewed the ability of EVs to modulate tissue repair and regeneration, focusing on their roles and therapeutic potential as immunomodulatory messengers. In this perspective, we discussed the open questions regarding the dual role of EVs in immune system, as well as the technical limitation of the procedure for EVs isolation and administration in clinical practices. EV-based therapies require further studies to consider EVs as promising candidate for a novel cell-free therapy in the context of regeneration medicine.

  17. Morphological and topological transformations of lipid bilayer vesicles

    Science.gov (United States)

    Nomura, Fumimasa; Honda, Makoto; Takeda, Shuichi; Umeda, Tamiki; Takiguchi, Kingo; Hotani, Hirokazu

    2000-06-01

    Liposomes are the micro compartments made of lipid bilayer membrane of which characteristics are quite similar to those of biological membrane. To form artificial cell-like structure, we made liposomes that contained subunit of cytoskeletons: tubulin or actin. Spherical liposomes were transformed into bipolar or cell-like shape by mechanical force generated by the polymerization of encapsulated subunits of microtubules. Disk or dumbbell shape was generated by the polymerization of encapsulated action. Dynamic processes of morphological transformations of liposomes were visualized by the high intensity dark-field light microscopy. Topological changes such as fusion and division of membrane vesicles also play an essential role in cellular activities. We investigated the mechanism of these topological transformations by visualizing their real-time processes. A variety of novel topological transformations were found, including the opening-up of liposomes and the direct expulsion of inner vesicles. .

  18. Numerical computations of the dynamics of fluidic membranes and vesicles

    CERN Document Server

    Barrett, John W; Nürnberg, Robert

    2015-01-01

    Vesicles and many biological membranes are made of two monolayers of lipid molecules and form closed lipid bilayers. The dynamical behaviour of vesicles is very complex and a variety of forms and shapes appear. Lipid bilayers can be considered as a surface fluid and hence the governing equations for the evolution include the surface (Navier--)Stokes equations, which in particular take the membrane viscosity into account. The evolution is driven by forces stemming from the curvature elasticity of the membrane. In addition, the surface fluid equations are coupled to bulk (Navier--)Stokes equations. We introduce a parametric finite element method to solve this complex free boundary problem, and present the first three dimensional numerical computations based on the full (Navier--)Stokes system for several different scenarios. For example, the effects of the membrane viscosity, spontaneous curvature and area difference elasticity (ADE) are studied. In particular, it turns out, that even in the case of no viscosit...

  19. CAPS and Munc13: CATCHRs that SNARE vesicles

    Directory of Open Access Journals (Sweden)

    Declan J James

    2013-12-01

    Full Text Available Abstract. CAPS (Calcium-dependent Activator Protein for Secretion, aka CADPS and Munc13 (Mammalian Unc-13 proteins function to prime vesicles for Ca2+-triggered exocytosis in neurons and neuroendocrine cells. CAPS and Munc13 proteins contain conserved C-terminal domains that promote the assembly of SNARE complexes for vesicle priming. Similarities of the C-terminal domains of CAPS/Munc13 proteins with CATCHR (Complex Associated with Tethering Containing Helical Rods domains in multi-subunit tethering complexes have been reported. Multi-subunit tethering complexes coordinate multiple interactions for SNARE complex assembly at constitutive membrane fusion steps. We review aspects of these diverse tethering and priming factors to identify common operating principles.

  20. Production and Characterization of Extracellular Vesicles in Malaria.

    Science.gov (United States)

    Mbagwu, Smart; Walch, Michael; Filgueira, Luis; Mantel, Pierre-Yves

    2017-01-01

    Growing attention is drawn toward the role of extracellular vesicles (EVs) in infectious diseases. EVs, which are small vesicles released by cells, are involved in cellular communication, immune regulation, and pathogenesis. EVs act as messenger carrying functional cargoes, including RNA, DNA, lipids and proteins from a donor cell to regulate the function of a recipient cell. In malaria, EVs play a key role in regulating the progression from the blood to the transmission stage by promoting the switch between asexual and sexual stages that are taken up by mosquitoes. In addition to their role in parasite communication, EVs modulate the immune system and regulate endothelial cell function.In this chapter, we describe protocols to isolate, purify and characterize EVs derived from Plasmodium falciparum infected red blood cell culture.

  1. Shear-Induced Deformation of Surfactant Multilamellar Vesicles

    Science.gov (United States)

    Pommella, Angelo; Caserta, Sergio; Guida, Vincenzo; Guido, Stefano

    2012-03-01

    Surfactant multilamellar vesicles (SMLVs) play a key role in the formulation of many industrial products, such as detergents, foodstuff, and cosmetics. In this Letter, we present the first quantitative investigation of the flow behavior of single SMLVs in a shearing parallel plate apparatus. We found that SMLVs are deformed and oriented by the action of shear flow while keeping constant volume and exhibit complex dynamic modes (i.e., tumbling, breathing, and tank treading). This behavior can be explained in terms of an excess area (as compared to a sphere of the same volume) and of microstructural defects, which were observed by 3D shape reconstruction through confocal microscopy. Furthermore, the deformation and orientation of SMLVs scale with radius R in analogy with emulsion droplets and elastic capsules (instead of R3, such as in unilamellar vesicles). A possible application of the physical insight provided by this Letter is in the rationale design of processing methods of surfactant-based systems.

  2. Targeting sodium channels in cardiac arrhythmia

    NARCIS (Netherlands)

    Remme, Carol Ann; Wilde, Arthur A. M.

    2014-01-01

    Cardiac voltage-gated sodium channels are responsible for proper electrical conduction in the heart. During acquired pathological conditions and inherited sodium channelopathies, altered sodium channel function causes conduction disturbances and ventricular arrhythmias. Although the clinical,

  3. Pulmonary Extracellular Vesicles as Mediators of Local and Systemic Inflammation

    OpenAIRE

    Wahlund, Casper J. E.; Eklund, Anders; Grunewald, Johan; Gabrielsson, Susanne

    2017-01-01

    Cells of the airways are constantly exposed to environmental hazards including cigarette smoke, irritants, pathogens, and mechanical insults. Maintaining barrier integrity is vital, and mounting responses to threats depends on intercellular communication. Extracellular vesicles (EVs), including exosomes and microvesicles, are major signal mediators between cells, shuttling cargo in health and disease. Depending on the state of the originating cells, EVs are capable of inducing proinflammatory...

  4. Isolation and characterization of platelet-derived extracellular vesicles

    OpenAIRE

    Aatonen, Maria T.; Öhman, Tiina; Nyman, Tuula A.; Laitinen, Saara; Grönholm, Mikaela; Siljander, Pia R.-M.

    2014-01-01

    Background: Platelet-derived extracellular vesicles (EVs) participate, for example, in haemostasis, immunity and development. Most studies of platelet EVs have targeted microparticles, whereas exosomes and EV characterization under various conditions have been less analyzed. Studies have been hampered by the difficulty in obtaining EVs free from contaminating cells and platelet remnants. Therefore, we optimized an EV isolation protocol and compared the quantity and protein content of EVs indu...

  5. Association of Randall's Plaques with Collagen Fibers and Membrane Vesicles

    Science.gov (United States)

    Khan, Saeed R.; Rodriguez, Douglas E.; Gower, Laurie B.; Monga, Manoj

    2013-01-01

    Background Idiopathic calcium oxalate (CaOx) kidney stones develop by deposition of CaOx crystals on Randall's plaques (RP). Mechanisms involved in RP formation are still unclear. Objective It is our hypotheses that RP formation is similar to vascular calcification involving components of extracellular matrix including membrane bound vesicles (MV) and collagen fibers. In order to verify our hypothesis we critically examined renal papillary tissue from stone patients. Methods 4 mm cold-cup biopies of renal papillae were performed on fifteen idiopathic stone patients undergoing PCNL. Tissue was immediately fixed and processed for analyses by various light and electron microscopic techniques. Results and Limitations Spherulitic CaP crystals, the hallmark of RP's, were seen in all samples examined. They were seen in interstitium as well as laminated basement membrane of tubular epithelia. Large crystalline deposits comprised of dark elongated strands mixed with spherulites. Strands showed banded patterns similar to collagen. Crystal deposits were surrounded by collagen fibers and membrane bound vesicles. Energy dispersive x-ray microanalyses (EDX) and electron diffraction identified the crystals as hydroxyapatite. The number of kidneys examined is small and urinary data was not available for all the patients. Conclusions Results presented here show that crystals in the Randall's plaques are associated with both the collagen as well as MV. Collagen fibers appeared calcified and vesicles contained crystals. We conclude that crystal deposition in renal papillae may have started with membrane vesicle induced nucleation and grew by addition of crystals on the periphery within a collagen framework. PMID:22266007

  6. Isolation and Characterization of Chick Epiphyseal Cartilage Matrix Vesicle Proteolipid

    Science.gov (United States)

    1988-01-01

    initial calcification in dentine and enamel . J. Ultrastr. Res., 41: 1-17. Bernard GW and Pease DC. 1969. An electron microscopic study of initial...characterization of matrix vesicle protease. Bone, 6: 470. ----------- -40 IT 7, T 7 69 Ketenjian AY and Arsenis C. 1975. Morphological and...J. Biol. Chem., 258: 8601-8607. Siska RF and Provenza DV. 1972. Initial dentin formation in human deciduous teeth . An electron microscopic study

  7. Dimensional characterization of extracellular vesicles using atomic force microscopy

    Science.gov (United States)

    Sebaihi, N.; De Boeck, B.; Yuana, Y.; Nieuwland, R.; Pétry, J.

    2017-03-01

    Extracellular vesicles (EV) are small biological entities released from cells into body fluids. EV are recognized as mediators in intercellular communication and influence important physiological processes. It has been shown that the concentration and composition of EV in body fluids may differ from healthy subjects to patients suffering from particular disease. So, EV have gained a strong scientific and clinical interest as potential biomarkers for diagnosis and prognosis of disease. Due to their small size, accurate detection and characterization of EV remain challenging. The aim of the presented work is to propose a characterization method of erythrocyte-derived EV using atomic force microscopy (AFM). The vesicles are immobilized on anti-CD235a-modified mica and analyzed by AFM under buffer liquid and dry conditions. EV detected under both conditions show very similar sizes namely ~30 nm high and ~90 nm wide. The size of these vesicles remains stable over drying time as long as 7 d at room temperature. Since the detected vesicles are not spherical, EV are characterized by their height and diameter, and not only by the height as is usually done for spherical nanoparticles. In order to obtain an accurate measurement of EV diameters, the geometry of the AFM tip was evaluated to account for the lateral broadening artifact inherent to AFM measurements. To do so, spherical polystyrene (PS) nanobeads and EV were concomitantly deposited on the same mica substrate and simultaneously measured by AFM under dry conditions. By applying this procedure, direct calibration of the AFM tip could be performed together with EV characterization under identical experimental conditions minimizing external sources of uncertainty on the shape and size of the tip, thus allowing standardization of EV measurement.

  8. Preparation of PVP hydrogel nanoparticles using lecithin vesicles

    Directory of Open Access Journals (Sweden)

    Vânia Blasques Bueno

    2010-01-01

    Full Text Available Hydrogels micro, sub-micro and nanoparticles are of great interest for drug encapsulation and delivery or as embolotherapic agents. In this work it is described the preparation of nano and sub-microparticles of pre-formed, high molecular weight and monomer free poly(N-vinyl-2-pyrrolidone encapsulated inside the core of lecithin vesicles. The hydrogel particles are formed with a very narrow diameter distribution, of about 800 nm, and a moderate swelling ratio, of approximately 10.

  9. Fluorescent Probe Study of AOT Vesicle Membranes and Their Alteration upon Addition of Aniline or the Aniline Dimer p-Aminodiphenylamine (PADPA).

    Science.gov (United States)

    Iwasaki, Fumihiko; Luginbühl, Sandra; Suga, Keishi; Walde, Peter; Umakoshi, Hiroshi

    2017-02-28

    Artificial vesicles formed from sodium bis(2-ethylhexyl) sulfosuccinate (AOT) in aqueous solution are used successfully as additives for enzymatic oligomerizations or polymerizations of aniline or the aniline dimer p-aminodiphenylamine (PADPA) under slightly acidic conditions (e.g., pH 4.3 with horseradish peroxidase and hydrogen peroxide as oxidants). In these systems, the reactions occur membrane surface-confined. Therefore, (i) the physicochemical properties of the vesicle membrane and (ii) the interaction of aniline or PADPA with the AOT membrane play crucial roles in the progress and final outcome of the reactions. For this reason, the properties of AOT vesicles with and without added aniline or PADPA were investigated by using two fluorescent membrane probes: 1,6-diphenyl-1,3,5-hexatriene (DPH) and 6-lauroyl-2-dimethylaminonaphthalene (Laurdan). DPH and Laurdan were used as "sensors" of the membrane fluidity, surface polarity, and membrane phase state. Moreover, the effect of hexanol, alone or in combination with aniline or PADPA, as a possible modifier of the AOT membrane, was also studied with the aim of evaluating whether the membrane fluidity and surface polarity is altered significantly by hexanol, which, in turn, may have an influence on the mentioned types of reactions. The data obtained indicate that the AOT vesicle membrane at room temperature and pH 4.3 (0.1 M NaH2PO4) is more fluid and has a more polar surface than in the case of fluid phospholipid vesicle membranes formed from 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC). Furthermore, the fluorescence measurements indicate that mixed AOT-hexanol membranes are less fluid than pure AOT membranes and that they have a lower surface polarity than pure AOT membranes. PADPA strongly binds to AOT and to mixed AOT/hexanol membranes and leads to drastic changes in the membrane properties (decrease in fluidity and surface polarity), resulting in Laurdan fluorescence spectra, which are characteristic for

  10. Sodium fire testing: structural evaluation of sodium fire suppression system

    Energy Technology Data Exchange (ETDEWEB)

    None

    1984-08-01

    This report describes the development and the lessons learned from the Clinch River Breeder Reactor Sodium Fire Testing Program (DRS 26.03). The purpose of this program was to evaluate the behavior of the Sodium Fire Suppression System and validate the analytical techniques used in the calculation of the effects of sodium fires in air-filled cells. This report focuses on the fire suppression capability and the structural integrity of the Fire Suppression System. System features are discussed; the test facility is described and the key results are provided. Modifications to the fire suppression system and the plant made as a result of test experience are also discussed.

  11. Tables of thermodynamic properties of sodium

    Energy Technology Data Exchange (ETDEWEB)

    Fink, J.K.

    1982-06-01

    The thermodynamic properties of saturated sodium, superheated sodium, and subcooled sodium are tabulated as a function of temperature. The temperature ranges are 380 to 2508 K for saturated sodium, 500 to 2500 K for subcooled sodium, and 400 to 1600 K for superheated sodium. Tabulated thermodynamic properties are enthalpy, heat capacity, pressure, entropy, density, instantaneous thermal expansion coefficient, compressibility, and thermal pressure coefficient. Tables are given in SI units and cgs units.

  12. Complexin synchronizes primed vesicle exocytosis and regulates fusion pore dynamics

    Science.gov (United States)

    Dhara, Madhurima; Yarzagaray, Antonio; Schwarz, Yvonne; Dutta, Soumyajit; Grabner, Chad; Moghadam, Paanteha K.; Bost, Anneka; Schirra, Claudia; Rettig, Jens; Reim, Kerstin; Brose, Nils; Mohrmann, Ralf

    2014-01-01

    ComplexinII (CpxII) and SynaptotagminI (SytI) have been implicated in regulating the function of SNARE proteins in exocytosis, but their precise mode of action and potential interplay have remained unknown. In this paper, we show that CpxII increases Ca2+-triggered vesicle exocytosis and accelerates its secretory rates, providing two independent, but synergistic, functions to enhance synchronous secretion. Specifically, we demonstrate that the C-terminal domain of CpxII increases the pool of primed vesicles by hindering premature exocytosis at submicromolar Ca2+ concentrations, whereas the N-terminal domain shortens the secretory delay and accelerates the kinetics of Ca2+-triggered exocytosis by increasing the Ca2+ affinity of synchronous secretion. With its C terminus, CpxII attenuates fluctuations of the early fusion pore and slows its expansion but is functionally antagonized by SytI, enabling rapid transmitter discharge from single vesicles. Thus, our results illustrate how key features of CpxII, SytI, and their interplay transform the constitutively active SNARE-mediated fusion mechanism into a highly synchronized, Ca2+-triggered release apparatus. PMID:24687280

  13. Extracellular Vesicles and Their Convergence with Viral Pathways

    Directory of Open Access Journals (Sweden)

    Thomas Wurdinger

    2012-01-01

    Full Text Available Extracellular vesicles (microvesicles, such as exosomes and shed microvesicles, contain a variety of molecules including proteins, lipids, and nucleic acids. Microvesicles appear mostly to originate from multivesicular bodies or to bud from the plasma membrane. Here, we review the convergence of microvesicle biogenesis and aspects of viral assembly and release pathways. Herpesviruses and retroviruses, amongst others, recruit several elements from the microvesicle biogenesis pathways for functional virus release. In addition, noninfectious pleiotropic virus-like vesicles can be released, containing viral and cellular components. We highlight the heterogeneity of microvesicle function during viral infection, addressing microvesicles that can either block or enhance infection, or cause immune dysregulation through bystander action in the immune system. Finally, endogenous retrovirus and retrotransposon elements deposited in our genomes millions of years ago can be released from cells within microvesicles, suggestive of a viral origin of the microvesicle system or perhaps of an evolutionary conserved system of virus-vesicle codependence. More research is needed to further elucidate the complex function of the various microvesicles produced during viral infection, possibly revealing new therapeutic intervention strategies.

  14. Thin shell vesicles composed of hydrophilic plate-like nanoparticles

    Science.gov (United States)

    Subramaniam, Anand; Wan, Jiandi; Gopinath, Arvind; Stone, Howard

    2011-03-01

    Nanopowders of graphene oxide, montmorillonite and laponite spontaneously delaminate into ultrathin nanoscopic plates when dispersed in water. These plates, which are typically ~ 1 nm thick and microns in lateral dimension, have found many uses as precursors to graphene, ceramics, layer-by-layer structures, and as structural modifiers of nanocomposites. Here we show that mechanical forces due to shear in a narrow gap can assemble hydrophilic plate-like particles on air bubbles, forming stable nanoplated armored bubbles. Translucent inorganic vesicles (vesicles defined here as closed thin-shelled structures with the same liquid inside and outside) of these particles are produced when the nanoplated armored bubbles are exposed to common water-miscible organic liquids and surfactants. These inorganic vesicles are mechanically robust, have walls that are about six nanometres thick, and are perforated with pores of submicron dimensions. We characterize the phenomenon and find that a wetting transition at the scale of the nanoparticles is the primary mechanism of formation. The discovery of these novel inorganic structures raises a wealth of questions of fundamental interest in materials and surface science.

  15. Isolation and characterization of platelet-derived extracellular vesicles.

    Science.gov (United States)

    Aatonen, Maria T; Ohman, Tiina; Nyman, Tuula A; Laitinen, Saara; Grönholm, Mikaela; Siljander, Pia R-M

    2014-01-01

    Platelet-derived extracellular vesicles (EVs) participate, for example, in haemostasis, immunity and development. Most studies of platelet EVs have targeted microparticles, whereas exosomes and EV characterization under various conditions have been less analyzed. Studies have been hampered by the difficulty in obtaining EVs free from contaminating cells and platelet remnants. Therefore, we optimized an EV isolation protocol and compared the quantity and protein content of EVs induced by different agonists. Platelets isolated with iodixanol gradient were activated by thrombin and collagen, lipopolysaccharide (LPS) or Ca(2+) ionophore. Microparticles and exosomes were isolated by differential centrifugations. EVs were quantitated by nanoparticle tracking analysis (NTA) and total protein. Size distributions were determined by NTA and electron microscopy. Proteomics was used to characterize the differentially induced EVs. The main EV populations were 100-250 nm and over 90% were vesicle subpopulations. Although platelets constitutively release EVs, vesiculation can be increased, and the activation pathway determines the number and the cargo of the formed EVs. These activation-dependent variations render the use of protein content in sample normalization invalid. Since most platelet EVs are 100-250 nm, only a fraction has been analyzed by previously used methods, for example, flow cytometry. As the EV subpopulations could not be distinguished and large vesicle populations may be lost by differential centrifugation, novel methods are required for the isolation and the differentiation of all EVs.

  16. Durable vesicles for reconstitution of membrane proteins in biotechnology.

    Science.gov (United States)

    Beales, Paul A; Khan, Sanobar; Muench, Stephen P; Jeuken, Lars J C

    2017-02-08

    The application of membrane proteins in biotechnology requires robust, durable reconstitution systems that enhance their stability and support their functionality in a range of working environments. Vesicular architectures are highly desirable to provide the compartmentalisation to utilise the functional transmembrane transport and signalling properties of membrane proteins. Proteoliposomes provide a native-like membrane environment to support membrane protein function, but can lack the required chemical and physical stability. Amphiphilic block copolymers can also self-assemble into polymersomes: tough vesicles with improved stability compared with liposomes. This review discusses the reconstitution of membrane proteins into polymersomes and the more recent development of hybrid vesicles, which blend the robust nature of block copolymers with the biofunctionality of lipids. These novel synthetic vesicles hold great promise for enabling membrane proteins within biotechnologies by supporting their enhanced in vitro performance and could also contribute to fundamental biochemical and biophysical research by improving the stability of membrane proteins that are challenging to work with. © 2017 The Author(s).

  17. Origin of life: LUCA and extracellular membrane vesicles (EMVs)

    Science.gov (United States)

    Gill, S.; Forterre, P.

    2016-01-01

    Cells from the three domains of life produce extracellular membrane vesicles (EMVs), suggesting that EMV production is an important aspect of cellular physiology. EMVs have been implicated in many aspects of cellular life in all domains, including stress response, toxicity against competing strains, pathogenicity, detoxification and resistance against viral attack. These EMVs represent an important mode of inter-cellular communication by serving as vehicles for transfer of DNA, RNA, proteins and lipids between cells. Here, we review recent progress in the understanding of EMV biology and their various roles. We focus on the role of membrane vesicles in early cellular evolution and how they would have helped shape the nature of the last universal common ancestor. A membrane-protected micro-environment would have been a key to the survival of spontaneous molecular systems and efficient metabolic reactions. Interestingly, the morphology of EMVs is strongly reminiscent of the morphology of some virions. It is thus tempting to make a link between the origin of the first protocell via the formation of vesicles and the origin of viruses.

  18. Myeloid extracellular vesicles: messengers from the demented brain

    Directory of Open Access Journals (Sweden)

    Annamaria eNigro

    2016-01-01

    Full Text Available Blood-borne monocyte derived cells play a pivotal, initially unrecognized, role in most central nervous system disorders, including diseases initially classified as purely neurodegenerative (i.e. AD, PD, and ALS. Their trafficking to the brain and spinal cord has been extensively studied in classical neuroinflammatory disorders such as multiple sclerosis. Central nervous system resident myeloid cells, namely microglia and perivascular macrophages, also are in the spotlight of investigations on neurological disorders. Myeloid cells, such as infiltrating macrophages and microglia, have been described as having both protective and destructive features in neurological disorders, thus identification of their functional phenotype during disease evolution would be of paramount importance. Extracellular vesicles, namely exosomes and shed vesicles, are released by virtually any cell type and can be detected and identified in terms of cell origin in biological fluids. They therefore constitute an ideal tool to access information on cells residing in an inaccessible site such as the brain. We will review here available information on extracellular vesicles detection in neurological disorders with special emphasis on neurodegenerative diseases.

  19. A Hierarchical Convolutional Neural Network for vesicle fusion event classification.

    Science.gov (United States)

    Li, Haohan; Mao, Yunxiang; Yin, Zhaozheng; Xu, Yingke

    2017-09-01

    Quantitative analysis of vesicle exocytosis and classification of different modes of vesicle fusion from the fluorescence microscopy are of primary importance for biomedical researches. In this paper, we propose a novel Hierarchical Convolutional Neural Network (HCNN) method to automatically identify vesicle fusion events in time-lapse Total Internal Reflection Fluorescence Microscopy (TIRFM) image sequences. Firstly, a detection and tracking method is developed to extract image patch sequences containing potential fusion events. Then, a Gaussian Mixture Model (GMM) is applied on each image patch of the patch sequence with outliers rejected for robust Gaussian fitting. By utilizing the high-level time-series intensity change features introduced by GMM and the visual appearance features embedded in some key moments of the fusion process, the proposed HCNN architecture is able to classify each candidate patch sequence into three classes: full fusion event, partial fusion event and non-fusion event. Finally, we validate the performance of our method on 9 challenging datasets that have been annotated by cell biologists, and our method achieves better performances when comparing with three previous methods. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Charged copolypeptide vesicles with controlled size for intracellular drug delivery

    Science.gov (United States)

    Holowka, Eric Peter

    Much focus has been given to the synthesis of polypeptidic based materials due to their unique structural features. These polypeptides commonly are amphiphilic in character that benefit from secondary structural features associated with one of the polymer blocks. These features, such as alpha-helix and beta-sheet conformations, allow for control over nanoscale ordering through self-assembly for use in biological sensors and therapeutic drug delivery. We report the preparation and characterization of charged amphiphilic block copolypeptide vesicle formers using transition metal mediated living ring-opening polymerization of N-carboxyanhydrides (NCAs). The vesicle membranes show fluidic properties suggested by dynamic physical behavior allowing for fine size adjustments using liposomal extrusion methods. This extrusion also allows for a facile mode of encapsulation of biomolecules for drug delivery. Modification of the charged residues has shown vesicle stability under osmotic and thermal stress, in pH buffers, and serum cell media, as well as the ability for lipid interaction and cellular interactions.

  1. Quantitative and qualitative analysis of nano-sized vesicles released by dendritic cells and T cells. Towards deciphering the role of extracellular vesicles in immune cell communication

    NARCIS (Netherlands)

    van der Vlist, E.J.|info:eu-repo/dai/nl/314640908

    2013-01-01

    Many cell types release nano-sized vesicles, which can be found in body fluids as well as in cell culture-conditioned medium. These extracellular vesicles (EV) have been identified as vehicles for intercellular communication and are thought to be involved in many (patho)physiological processes. They

  2. Spermatozoa as a transport system of large unilamellar lipid vesicles into the oocyte.

    Science.gov (United States)

    Geerts, N; McGrath, J; Stronk, J N; Vanderlick, T K; Huszar, G

    2014-04-01

    In addition to their role as man-made membranes, vesicles continue to be investigated as carriers for drug delivery. While most research focuses on their injectable properties, here a new delivery strategy is proposed. It is shown that spermatozoa can transport vesicles of variable composition. For human spermatozoa, the vesicles started to show binding after 20 mol% of the nonbinding vesicle backbone lipids were substituted with positive, negative, cerebroside or ganglioside lipids. Vesicle binding is a dynamic process with constant 'on' and 'off' binding. The physiological and motility attributes of the spermatozoa are not affected by the attached vesicles. Sperm swimming characteristics changed only marginally. Also, the activation status of the acrosomal membrane, tested with the fluorescent probe Pisum sativum agglutinin, was not affected by vesicle binding. Moreover, the hyaluronic acid-binding test showed that viable, fully developed spermatozoa will attach and remain bound to hyaluronic acid-coated slides regardless of vesicle binding. Therefore a new 'hybrid' delivery system was created with human spermatozoa, and tested with a mouse IVF system. Large unilamellar vesicles physisorbed to mouse spermatozoa can not only penetrate the mouse oocytes in these proof-of-principle experiments, but also deliver the cargo placed within the vesicles. Copyright © 2013 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

  3. Emergent properties of extracellular vesicles: a holistic approach to decode the complexity of intercellular communication networks.

    Science.gov (United States)

    Gho, Yong Song; Lee, Changjin

    2017-06-27

    Shedding of nano-sized bilayered extracellular vesicles and extracellular vesicle-mediated intercellular communication are evolutionarily conserved biological processes. Communication between cells and the environment is an essential process in living organisms and dysregulation of intercellular communication leads to various diseases. Thus, systematic studies on extracellular vesicles, also known as exosomes, microvesicles, and outer membrane vesicles, are critical for a deeper understanding of intercellular communication networks that are crucial for decoding the exact causes of various difficult-to-cure diseases. Recent progress in this emerging field reveals that extracellular vesicles are endogenous carriers of specific subsets of proteins, mRNAs, miRNAs, and other bioactive materials, as well as play diverse pathophysiological roles. However, certain issues regarding diverse subtypes and the complex pathophysiological roles of extracellular vesicles are not yet clearly elucidated. In this review, we first briefly introduce the complexity of extracellular vesicles in terms of their vesicular cargos and protein-protein interaction networks, their diverse subtypes, and multifaceted pathophysiological functions. Then, we introduce the limitation of reductionist approaches in understanding the complexity of extracellular vesicles. We finally suggest that molecular systems biology approaches based on the concept of emergent properties are essential for a comprehensive understanding of the complex pathophysiological functions of heterogeneous extracellular vesicles, either at the single vesicle level or at a systems level as a whole.

  4. Hyperbranched polymer vesicles: from self-assembly, characterization, mechanisms, and properties to applications.

    Science.gov (United States)

    Jiang, Wenfeng; Zhou, Yongfeng; Yan, Deyue

    2015-06-21

    Vesicles, including lipid vesicles, surfactant vesicles, as well as polymer vesicles, have been extensively investigated over the past fifty years. Among them, polymer vesicles have attracted more and more attention because of their low permeability, superior stability and toughness, in addition to the numerous possibilities for tailoring physical, chemical and biological properties. Polymer vesicles are generally fabricated through the self-assembly of amphiphilic polymers with a linear architecture. Recently, as representative polymers with a highly branched three-dimensional architecture, hyperbranched polymers have also exhibited great potential for preparing vesicles. The resultant hyperbranched polymer vesicles, defined as branched-polymersomes (BPs), have shown unique properties, such as giant and easily tuned vesicle sizes, facile functionalization, a special formation mechanism, and appealing solution behaviours. In this tutorial review, ten years of advances in BPs have been summarized since their first discovery in the year 2004, including the syntheses of vesicle-forming hyperbranched polymers, self-assembly methods, self-assembly mechanisms, as well as the special properties. In addition, the cytomimetic, biomedical and other initiatory applications of BPs are also included.

  5. Myo1c binding to submembrane actin mediates insulin-induced tethering of GLUT4 vesicles

    Science.gov (United States)

    Boguslavsky, Shlomit; Chiu, Tim; Foley, Kevin P.; Osorio-Fuentealba, Cesar; Antonescu, Costin N.; Bayer, K. Ulrich; Bilan, Philip J.; Klip, Amira

    2012-01-01

    GLUT4-containing vesicles cycle between the plasma membrane and intracellular compartments. Insulin promotes GLUT4 exocytosis by regulating GLUT4 vesicle arrival at the cell periphery and its subsequent tethering, docking, and fusion with the plasma membrane. The molecular machinery involved in GLUT4 vesicle tethering is unknown. We show here that Myo1c, an actin-based motor protein that associates with membranes and actin filaments, is required for insulin-induced vesicle tethering in muscle cells. Myo1c was found to associate with both mobile and tethered GLUT4 vesicles and to be required for vesicle capture in the total internal reflection fluorescence (TIRF) zone beneath the plasma membrane. Myo1c knockdown or overexpression of an actin binding–deficient Myo1c mutant abolished insulin-induced vesicle immobilization, increased GLUT4 vesicle velocity in the TIRF zone, and prevented their externalization. Conversely, Myo1c overexpression immobilized GLUT4 vesicles in the TIRF zone and promoted insulin-induced GLUT4 exposure to the extracellular milieu. Myo1c also contributed to insulin-dependent actin filament remodeling. Thus we propose that interaction of vesicular Myo1c with cortical actin filaments is required for insulin-mediated tethering of GLUT4 vesicles and for efficient GLUT4 surface delivery in muscle cells. PMID:22918957

  6. Susceptibility of Clostridium difficile to the food preservatives sodium nitrite, sodium nitrate and sodium metabisulphite.

    Science.gov (United States)

    Lim, Su-Chen; Foster, Niki F; Riley, Thomas V

    2016-02-01

    Clostridium difficile is an important enteric pathogen of humans and food animals. Recently it has been isolated from retail foods with prevalences up to 42%, prompting concern that contaminated foods may be one of the reasons for increased community-acquired C. difficile infection (CA-CDI). A number of studies have examined the prevalence of C. difficile in raw meats and fresh vegetables; however, fewer studies have examined the prevalence of C. difficile in ready-to-eat meat. The aim of this study was to investigate the in vitro susceptibility of 11 C. difficile isolates of food animal and retail food origins to food preservatives commonly used in ready-to-eat meats. The broth microdilution method was used to determine the minimum inhibitory concentrations (MIC) and minimum bactericidal concentrations (MBC) for sodium nitrite, sodium nitrate and sodium metabisulphite against C. difficile. Checkerboard assays were used to investigate the combined effect of sodium nitrite and sodium nitrate, commonly used in combination in meats. Modal MIC values for sodium nitrite, sodium nitrate and sodium metabisulphite were 250 μg/ml, >4000 μg/ml and 1000 μg/ml, respectively. No bactericidal activity was observed for all three food preservatives. The checkerboard assays showed indifferent interaction between sodium nitrite and sodium nitrate. This study demonstrated that C. difficile can survive in the presence of food preservatives at concentrations higher than the current maximum permitted levels allowed in ready-to-eat meats. The possibility of retail ready-to-eat meats contaminated with C. difficile acting as a source of CDI needs to be investigated. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Label-free tracking of single extracellular vesicles in a nano-fluidic optical fiber (Conference Presentation)

    Science.gov (United States)

    van der Pol, Edwin; Weidlich, Stefan; Lahini, Yoav; Coumans, Frank A. W.; Sturk, Auguste; Nieuwland, Rienk; Schmidt, Markus A.; Faez, Sanli; van Leeuwen, Ton G.

    2016-03-01

    Background: Extracellular vesicles, such as exosomes, are abundantly present in human body fluids. Since the size, concentration and composition of these vesicles change during disease, vesicles have promising clinical applications, including cancer diagnosis. However, since ~70% of the vesicles have a diameter vesicles remains challenging. Thus far, vesicles vesicles to be adhered to a surface. Consequently, the majority of vesicles have never been studied in their physiological environment. We present a novel label-free optical technique to track single vesicles vesicles were contained within a single-mode light-guiding silica fiber containing a 600 nm nano-fluidic channel. Light from a diode laser (660 nm wavelength) was coupled to the fiber, resulting in a strongly confined optical mode in the nano-fluidic channel, which continuously illuminated the freely diffusing vesicles inside the channel. The elastic light scattering from the vesicles, in the direction orthogonal to the fiber axis, was collected using a microscope objective (NA=0.95) and imaged with a home-built microscope. Results: We have tracked single urinary vesicles as small as 35 nm by elastic light scattering. Please note that vesicles are low-refractive index (nvesicles vesicle-based clinical applications.

  8. Extracellular Vesicles and Their Role in Urologic Malignancies.

    Science.gov (United States)

    Junker, Kerstin; Heinzelmann, Joana; Beckham, Carla; Ochiya, Takahiro; Jenster, Guido

    2016-08-01

    Research has increased significantly on small vesicles secreted by healthy and diseased cells. Recent discoveries have revealed their functional and biomarker roles in urologic diseases. Whether and how this knowledge of extracellular vesicles (EVs) affects translational research and clinical practices have become pertinent questions. To provide an overview of the currently available literature on the rising field of EVs, focusing on function and pathogenesis in urologic cancers and the usefulness of EVs as biomarkers. A systematic literature search was conducted using PubMed to identify original articles, review articles, and editorials regarding EVs in different types of urologic tumor diseases. Articles published between 2005 and 2015 were reviewed and selected with the consensus of all authors. Besides soluble factors, different types of EVs are involved in the complex cross talk between different cell types. EVs regulate normal physiologic processes like spermatogenesis and renal function, as well as disease-specific processes including bladder, kidney, and prostate cancer. The content of EVs is derived from the cytoplasm of the donor cell. The proteins and RNAs within these EVs can be isolated from body fluids (eg, urine and blood) and represent potential diagnostic and prognostic biomarkers. EVs are also candidate therapeutic targets and potentially useful as therapeutic vehicles. The current data suggest that EVs are important regulators of cell-cell communication. The growing knowledge about their roles in urologic malignancies provides the basis for novel therapeutic strategies. In addition, nucleic acid and the protein content of EVs holds promise for the discovery of urine- or serum-based biomarkers for kidney, bladder, and prostate cancer. Normal and cancer cells secrete small vesicles that contain proteins and RNAs from the cell of origin. Changes in the diseased cells can be detected by examining the altered content of these vesicles when secreted in

  9. Sodium diffusion in boroaluminosilicate glasses

    DEFF Research Database (Denmark)

    Smedskjaer, Morten M.; Zheng, Qiuju; Mauro, John C.

    2011-01-01

    Understanding the fundamentals of alkali diffusion in boroaluminosilicate (BAS) glasses is of critical importance for advanced glass applications, e.g., the production of chemically strengthened glass covers for personal electronic devices. Here, we investigate the composition dependence...... of isothermal sodium diffusion in BAS glasses by ion exchange, inward diffusion, and tracer diffusion experiments. By varying the [SiO2]/[Al2O3] ratio of the glasses, different structural regimes of sodium behavior are accessed. We show that the mobility of the sodium ions decreases with increasing [SiO2]/[Al2O...

  10. Teratogenicity of sodium valproate.

    Science.gov (United States)

    Alsdorf, Rachel; Wyszynski, Diego F

    2005-03-01

    The teratogenicity of the widely popular antiepileptic drug (AED) and mood stabiliser sodium valproate (also known as valproate, VPA) has been evidenced by previous research; however, these findings have often been limited by a small population sample of exposed women and a retrospective study design. Many factors contribute to the teratogenicity of VPA. These include the number of drugs that are co-administered, drug dosage, differences in maternal and/or infant metabolism, the gestational age of the fetus at exposure, and hereditary susceptibility. VPA has been associated with a variety of major and minor malformations, including a 20-fold increase in neural tube defects, cleft lip and palate, cardiovascular abnormalities, genitourinary defects, developmental delay, endocrinological disorders, limb defects, and autism. It has been suggested that polytherapy treatment in epileptic pregnant women increases the risk of teratogenicity in offspring. Furthermore, there is an established relationship between VPA dose and adverse outcome. Large single doses of VPA potentially cause high peak levels in the fetal serum resulting in deleterious effects. Currently there is an increase in the number of national and international pregnancy registries being formed in an effort to better identify the teratogenic effects of AEDs. These efforts hope to enhance our understanding of AEDs and their associated risks by addressing past study limitations.

  11. Sodium management in dialysis by conductivity.

    Science.gov (United States)

    Bosetto, A; Bene, B; Petitclerc, T

    1999-07-01

    The determination of dialysate sodium concentration is one of the challenges of dialysis prescription, because no accurate information on the predialytic sodium overload is available. Too low dialysate sodium is responsible for intradialytic intolerance symptoms, whereas too high sodium may lead to long-term water sodium overload with cardiovascular hazards (hypertension, left heart failure). We propose here a biofeedback system based on noninvasive repeated measures of ionic dialysance and plasma water conductivity used here as a surrogate of plasma water sodium. This system achieves a stable postdialytic sodium pool and subsequently a dialysate sodium concentration adapted to the inter dialytic sodium load. This new tool in dialysate sodium prescription aims at reducing the morbidity related to patient sodium balance impairment.

  12. Parametric Effect of Sodium Hydroxide and Sodium Carbonate on the Potency of a Degreaser

    OpenAIRE

    Babatope Abimbola Olufemi

    2016-01-01

    Experimental and statistical analysis was carried out on the comparative effect of sodium hydroxide and sodium carbonate on the potency of a laboratory produced degreaser in this work. The materials used include; octadecyl benzene sulphonic acid, sodium hydroxide, sodium carbonate, sodium metasilicate, carboxyl methyl cellulose (C.M.C), formadelhyde, perfume, colourant and distilled water. Different samples of degreaser were produced with varying composition of sodium hydroxide and sodium car...

  13. Growth and instability of a phospholipid vesicle in a bath of fatty acids

    Science.gov (United States)

    Dervaux, J.; Noireaux, V.; Libchaber, A. J.

    2017-06-01

    Using a microfluidic trap, we study the behavior of individual phospholipid vesicles in contact with fatty acids. We show that spontaneous fatty acids insertion inside the bilayer is controlled by the vesicle size, osmotic pressure difference across the membrane and fatty acids concentration in the external bath. Depending on these parameters, vesicles can grow spherically or become unstable and fragment into several daughter vesicles. We establish the phase diagram for vesicle growth and we derive a simple thermodynamic model that reproduces the time evolution of the vesicle volume. Finally, we show that stable growth can be achieved on an artificial cell expressing a simple set of bacterial cytoskeletal proteins, paving the way toward artificial cell reproduction.

  14. Vesicles from Amphiphilic Dumbbells and Janus Dendrimers: Bioinspired Self-Assembled Structures for Biomedical Applications

    Directory of Open Access Journals (Sweden)

    Soraya Taabache

    2017-07-01

    Full Text Available The current review focuses on vesicles obtained from the self-assembly of two types of dendritic macromolecules, namely amphiphilic Janus dendrimers (forming dendrimersomes and amphiphilic dumbbells. In the first part, we will present some synthetic strategies and the various building blocks that can be used to obtain dendritic-based macromolecules, thereby showing their structural versatility. We put our focus on amphiphilic Janus dendrimers and amphiphilic dumbbells that form vesicles in water but we also encompass vesicles formed thereof in organic solvents. The second part of this review deals with the production methods of these vesicles at the nanoscale but also at the microscale. Furthermore, the influence of various parameters (intrinsic to the amphiphilic JD and extrinsic—from the environment on the type of vesicle formed will be discussed. In the third part, we will review the numerous biomedical applications of these vesicles of nano- or micron-size.

  15. Salt, shake, fuse--giant hybrid polymer/lipid vesicles through mechanically activated fusion.

    Science.gov (United States)

    Henderson, Ian M; Paxton, Walter F

    2014-03-24

    Large (200 nm) poly(ethylene oxide)-b-poly(butadiene) polymer vesicles fuse into giant (>1 μm) vesicles with mild agitation in dilute aqueous NaCl solutions. This unusual effect is attributed to the salt-induced contraction of the poly(ethylene oxide) corona, reducing steric resistance between vesicles and, with agitation, increasing the probability of contact between the hydrophobic cores of adjacent membranes. In addition, NaCl and agitation facilitated the creation of giant hybrid vesicles from much smaller homogeneous polymersomes and liposomes. Whereas lipid vesicles do not readily fuse with each other under the same circumstances, they did fuse with polymersomes to produce hybrid polymer/lipid vesicles. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Wolbachia bacteria reside in host Golgi-related vesicles whose position is regulated by polarity proteins.

    Directory of Open Access Journals (Sweden)

    Kyung-Ok Cho

    Full Text Available Wolbachia pipientis are intracellular symbiotic bacteria extremely common in various organisms including Drosophila melanogaster, and are known for their ability to induce changes in host reproduction. These bacteria are present in astral microtubule-associated vesicular structures in host cytoplasm, but little is known about the identity of these vesicles. We report here that Wolbachia are restricted only to a group of Golgi-related vesicles concentrated near the site of membrane biogenesis and minus-ends of microtubules. The Wolbachia vesicles were significantly mislocalized in mutant embryos defective in cell/planar polarity genes suggesting that cell/tissue polarity genes are required for apical localization of these Golgi-related vesicles. Furthermore, two of the polarity proteins, Van Gogh/Strabismus and Scribble, appeared to be present in these Golgi-related vesicles. Thus, establishment of polarity may be closely linked to the precise insertion of Golgi vesicles into the new membrane addition site.

  17. The Role of Extracellular Vesicles: An Epigenetic View of the Cancer Microenvironment.

    Science.gov (United States)

    Qian, Zhongrun; Shen, Qi; Yang, Xi; Qiu, Yongming; Zhang, Wenbin

    2015-01-01

    Exosomes, microvesicles, and other extracellular vesicles are released by many cell types, including cancer cells and cancer-related immune cells. Extracellular vesicles can directly or indirectly facilitate the transfer of bioinformation to recipient cells or to the extracellular environment. In cancer, exosomes have been implicated in tumor initiation, proliferation, and metastasis. Extracellular vesicles can transmit proteins and nucleic acids that participate in DNA methylation, histone modification, and posttranscriptional regulation of RNA. Factors transmitted by extracellular vesicles reflect the donor cell status, and extracellular vesicles derived from tumor cells may be also responsible for altering expression of tumor promoting and tumor suppressing genes in recipient cells. Thus, circulating extracellular vesicles may act as biomarkers of cancer, and detection of these biomarkers may be applied to diagnosis or assessment of prognosis in patients with cancer.

  18. The biology and function of extracellular vesicles in nasopharyngeal carcinoma (Review).

    Science.gov (United States)

    You, Bo; Shan, Ying; Bao, Lili; Chen, Jing; Yang, Liu; Zhang, Qicheng; Zhang, Wei; Zhang, Zhenxin; Zhang, Jie; Shi, Si; You, Yiwen

    2018-01-01

    Extracellular vesicles are a heterogeneous group of membrane-enclosed vesicles, which play an important role in intercellular communication. Increasing number of studies have shown that tumor-derived extracellular vesicles might be involved in the transfer of oncogenic cargo (proteins, lipids, messenger RNA, microRNA, non-coding RNAs and DNA) through which cancer cells could shape the tumor microenvironment and influence tumor progression. Nasopharyngeal carcinoma-derived extracellular vesicles have also reported to facilitate tumor proliferation, metastasis and immune escape. Moreover, nasopharyngeal carcinoma-derived extracellular vesicles might serve as biomarkers for early diagnosis and therapeutic targets. The present review provides information on the biological and clinical significance of extracellular vesicles in tumors, especially in nasopharyngeal carcinoma.

  19. Agonists that increase [Ca2+]i halt the movement of cytoplasmatic vesicles in MDCK cells

    DEFF Research Database (Denmark)

    Bjælde, Randi Groslier; Árnadóttir, Sigrid Salling; Leipziger, Jens Georg

    2011-01-01

    of vesicles by 40%. Because all these perturbations increase [Ca²⁺]i, we speculated that this increase in [Ca²⁺]i was responsible for the vesicle arrest. Therefore, we tested the effect of the Ca²⁺ ionophore, ionomycin (1 μM), which in the presence of extracellular Ca²⁺ resulted in a considerable......Translocation of vesicles within the cytoplasm is essential to normal cell function. The vesicles are typically transported along the microtubules to their destination. The aim of this study was to characterize the vesicular movement in resting and stimulated renal epithelial cells. MDCK cells...... loaded with either quinacrine or acridine orange, dyes taken up by acidic vesicles, were observed at 37°C in semiopen perfusion chambers. Time-lapse series were analyzed by Imaris software. Our data revealed vigorous movement of stained vesicles in resting MDCK cells. These movements seem to require...

  20. Mapping organelle motion reveals a vesicular conveyor belt spatially replenishing secretory vesicles in stimulated chromaffin cells.

    Science.gov (United States)

    Maucort, Guillaume; Kasula, Ravikiran; Papadopulos, Andreas; Nieminen, Timo A; Rubinsztein-Dunlop, Halina; Meunier, Frederic A

    2014-01-01

    How neurosecretory cells spatially adjust their secretory vesicle pools to replenish those that have fused and released their hormonal content is currently unknown. Here we designed a novel set of image analyses to map the probability of tracked organelles undergoing a specific type of movement (free, caged or directed). We then applied our analysis to time-lapse z-stack confocal imaging of secretory vesicles from bovine Chromaffin cells to map the global changes in vesicle motion and directionality occurring upon secretagogue stimulation. We report a defined region abutting the cortical actin network that actively transports secretory vesicles and is dissipated by actin and microtubule depolymerizing drugs. The directionality of this "conveyor belt" towards the cell surface is activated by stimulation. Actin and microtubule networks therefore cooperatively probe the microenvironment to transport secretory vesicles to the periphery, providing a mechanism whereby cells globally adjust their vesicle pools in response to secretagogue stimulation.

  1. A novel multiplex bead-based platform highlights the diversity of extracellular vesicles

    OpenAIRE

    Wild, Stefan; Koliha, Nina; Wiencek, Yvonne; Heider, Ute; Jüngst, Christian; Kladt, Nikolay; Krauthäuser, Susanne; Ian C. D. Johnston; Bosio, Andreas; Schauss, Astrid

    2016-01-01

    The surface protein composition of extracellular vesicles (EVs) is related to the originating cell and may play a role in vesicle function. Knowledge of the protein content of individual EVs is still limited because of the technical challenges to analyse small vesicles. Here, we introduce a novel multiplex bead-based platform to investigate up to 39 different surface markers in one sample. The combination of capture antibody beads with fluorescently labelled detection antibodies allows the an...

  2. ACECLOFENAC ENCAPSULATED ETHANOLIC NANO-VESICLES FOR EFFECTIVE TREATMENT OF OSTEOART HRITIS

    OpenAIRE

    Arvinder Kaur et al

    2012-01-01

    In the present study, ethanolic nanovesicles of Aceclofenac developed for the site specific delivery to joints for effective treatment of osteoarthritis. Ethanolic nano-vesicles were prepared by solvent dispersion method. Vesicles were characterized for vesicular size, surface morphology, size and size distribution, zeta potential, entrapment efficiency. Formulations were also evaluated for drug-vesicle (excipients) interaction, in vitro permeation, in vitro deposition. The TEM showed dark ve...

  3. Why the need and how to approach the functional diversity of extracellular vesicles

    OpenAIRE

    Tkach, Mercedes; Kowal, Joanna; Théry, Clotilde

    2017-01-01

    In the past decade, cell-to-cell communication mediated by exosomes has attracted growing attention from biomedical scientists and physicians, leading to several recent publications in top-tier journals. Exosomes are generally defined as secreted membrane vesicles, or extracellular vesicles (EVs), corresponding to the intraluminal vesicles of late endosomal compartments, which are secreted upon fusion of multi-vesicular endosomes with the cell's plasma membrane. Cells, however, were shown to ...

  4. Plasma biomarker discovery in preeclampsia using a novel differential isolation technology for circulating extracellular vesicles.

    Science.gov (United States)

    Tan, Kok Hian; Tan, Soon Sim; Sze, Siu Kwan; Lee, Wai Kheong Ryan; Ng, Mor Jack; Lim, Sai Kiang

    2014-10-01

    To circumvent the complex protein milieu of plasma and discover robust predictive biomarkers for preeclampsia (PE), we investigate if phospholipid-binding ligands can reduce the milieu complexity by extracting plasma extracellular vesicles for biomarker discovery. Cholera toxin B chain (CTB) and annexin V (AV) which respectively binds GM1 ganglioside and phosphatidylserine were used to isolate extracellular vesicles from plasma of PE patients and healthy pregnant women. The proteins in the vesicles were identified using enzyme-linked immunosorbent assay, antibody array, and mass spectrometry. CTB and AV were found to bind 2 distinct groups of extracellular vesicles. Antibody array and enzyme-linked immunosorbent assay revealed that PE patients had elevated levels of CD105, interleukin-6, placental growth factor, tissue inhibitor of metallopeptidase 1, and atrial natriuretic peptide in cholera toxin B- but not AV-vesicles, and elevated levels of plasminogen activator inhibitor-1, pro-calcitonin, S100b, tumor growth factor β, vascular endothelial growth factor receptor 1, brain natriuretic peptide, and placental growth factor in both cholera toxin B- and AV-vesicles. CD9 level was elevated in cholera toxin B-vesicles but reduced in AV vesicles of PE patients. Proteome analysis revealed that in cholera toxin B-vesicles, 87 and 222 proteins were present only in PE patients and healthy pregnant women respectively while in AV-vesicles, 104 and 157 proteins were present only in PE and healthy pregnant women, respectively. This study demonstrated for the first time that CTB and AV bind unique extracellular vesicles, and their protein cargo reflects the disease state of the patient. The successful use of these 2 ligands to isolate circulating plasma extracellular vesicles for biomarker discovery in PE represents a novel technology for biomarker discovery that can be applied to other specialties. Copyright © 2014 Elsevier Inc. All rights reserved.

  5. Transferring intercellular signals and traits between cancer cells: extracellular vesicles as "homing pigeons".

    Science.gov (United States)

    Cesi, Giulia; Walbrecq, Geoffroy; Margue, Christiane; Kreis, Stephanie

    2016-06-10

    Extracellular vesicles are cell-derived vesicles, which can transport various cargos out of cells. From their cell of origin, the content molecules (proteins, non-coding RNAs including miRNAs, DNA and others) can be delivered to neighboring or distant cells and as such extracellular vesicles can be regarded as vehicles of intercellular communication or "homing pigeons". Extracellular vesicle shuttling is able to actively modulate the tumor microenvironment and can partake in tumor dissemination. In various diseases, including cancer, levels of extracellular vesicle secretion are altered resulting in different amounts and/or profiles of detectable vesicular cargo molecules and these distinct content profiles are currently being evaluated as biomarkers. Apart from their potential as blood-derived containers of specific biomarkers, the transfer of extracellular vesicles to surrounding cells also appears to be involved in the propagation of phenotypic traits. These interesting properties have put extracellular vesicles into the focus of many recent studies.Here we review findings on the involvement of extracellular vesicles in transferring traits of cancer cells to their surroundings and briefly discuss new data on oncosomes, a larger type of vesicle. A pressing issue in cancer treatment is rapidly evolving resistance to many initially efficient drug therapies. Studies investigating the role of extracellular vesicles in this phenomenon together with a summary of the technical challenges that this field is still facing, are also presented. Finally, emerging areas of research such as the analysis of the lipid composition on extracellular vesicles and cutting-edge techniques to visualise the trafficking of extracellular vesicles are discussed.

  6. Dietary sodium and cardiovascular disease.

    Science.gov (United States)

    Smyth, Andrew; O'Donnell, Martin; Mente, Andrew; Yusuf, Salim

    2015-06-01

    Although an essential nutrient, higher sodium intake is associated with increasing blood pressure (BP), forming the basis for current population-wide sodium restriction guidelines. While short-term clinical trials have achieved low intake (6 months). Guidelines assume that low sodium intake will reduce BP and reduce cardiovascular disease (CVD), compared to moderate intake. However, current observational evidence suggests a J-shaped association between sodium intake and CVD; the lowest risks observed with 3-5 g/day but higher risk with 5 g/day) and increased risk of CVD. Although lower intake may reduce BP, this may be offset by marked increases in neurohormones and other adverse effects which may paradoxically be adverse. Large randomised clinical trials with sufficient follow-up are required to provide robust data on the long-term effects of sodium reduction on CVD incidence. Until such trials are completed, current evidence suggests that moderate sodium intake for the general population (3-5 g/day) is likely the optimum range for CVD prevention.

  7. Extracellular Vesicles Produced by the Gram-positive Bacterium Bacillus subtilis are Disrupted by the Lipopeptide Surfactin

    Science.gov (United States)

    Brown, Lisa; Kessler, Anne; Cabezas-Sanchez, Pablo; Luque-Garcia, Jose L.; Casadevall, Arturo

    2014-01-01

    Summary Previously, extracellular vesicle production in Gram-positive bacteria was dismissed due to the absence of an outer membrane, where Gram-negative vesicles originate, and the difficulty in envisioning how such a process could occur through the cell wall. However, recent work has shown that Gram-positive bacteria produce extracellular vesicles and that the vesicles are biologically active. In this study, we show that Bacillus subtilis produces extracellular vesicles similar in size and morphology to other bacteria, characterized vesicles using a variety of techniques, provide evidence that these vesicles are actively produced by cells, show differences in vesicle production between strains, and identified a mechanism for such differences based on vesicle disruption. We found that in wild strains of B. subtilis, surfactin disrupted vesicles while in laboratory strains harboring a mutation in the gene sfp, vesicles accumulated in the culture supernatant. Surfactin not only lysed B. subtilis vesicles, but also vesicles from Bacillus anthracis, indicating a mechanism that crossed species boundaries. To our knowledge, this is the first time a gene and a mechanism has been identified in the active disruption of extracellular vesicles and subsequent release of vesicular cargo in Gram-positive bacteria. We also identify a new mechanism of action for surfactin. PMID:24826903

  8. 21 CFR 522.460 - Cloprostenol sodium.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Cloprostenol sodium. 522.460 Section 522.460 Food... Cloprostenol sodium. (a)(1) Specifications. Each milliliter of the aqueous solution contains 263 micrograms of cloprostenol sodium (equivalent to 250 micrograms of cloprostenol) in a sodium citrate, anhydrous citric acid...

  9. Technical Guidelines for Sodium Storage and Handling

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Y. B.; Kim, J. M.; Kim, T. J.; Nam, H. Y.; Lee, T. H.; Jeong, J. Y.; Choi, B. H.; Choi, J. H.

    2010-09-15

    This document presents as a technical guideline for education and training of beginners who engage in the sodium facility operation and R and D activities for the first time. This guideline covers the following technical areas. - General properties of sodium - Sodium handling technology - Sodium fire and fire fighting - Material safety data sheet(MSDS)

  10. Are Reductions in Population Sodium Intake Achievable?

    Directory of Open Access Journals (Sweden)

    Jessica L. Levings

    2014-10-01

    Full Text Available The vast majority of Americans consume too much sodium, primarily from packaged and restaurant foods. The evidence linking sodium intake with direct health outcomes indicates a positive relationship between higher levels of sodium intake and cardiovascular disease risk, consistent with the relationship between sodium intake and blood pressure. Despite communication and educational efforts focused on lowering sodium intake over the last three decades data suggest average US sodium intake has remained remarkably elevated, leading some to argue that current sodium guidelines are unattainable. The IOM in 2010 recommended gradual reductions in the sodium content of packaged and restaurant foods as a primary strategy to reduce US sodium intake, and research since that time suggests gradual, downward shifts in mean population sodium intake are achievable and can move the population toward current sodium intake guidelines. The current paper reviews recent evidence indicating: (1 significant reductions in mean population sodium intake can be achieved with gradual sodium reduction in the food supply, (2 gradual sodium reduction in certain cases can be achieved without a noticeable change in taste or consumption of specific products, and (3 lowering mean population sodium intake can move us toward meeting the current individual guidelines for sodium intake.

  11. 21 CFR 172.170 - Sodium nitrate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Sodium nitrate. 172.170 Section 172.170 Food and... Preservatives § 172.170 Sodium nitrate. The food additive sodium nitrate may be safely used in or on specified... sablefish, smoked, cured salmon, and smoked, cured shad, so that the level of sodium nitrate does not exceed...

  12. The Influence of Vesicle Shape and Medium Conductivity on Possible Electrofusion under a Pulsed Electric Field.

    Science.gov (United States)

    Liu, Linying; Mao, Zheng; Zhang, Jianhua; Liu, Na; Liu, Qing Huo

    2016-01-01

    The effects of electric field on lipid membrane and cells have been extensively studied in the last decades. The phenomena of electroporation and electrofusion are of particular interest due to their wide use in cell biology and biotechnology. However, numerical studies on the electrofusion of cells (or vesicles) with different deformed shapes are still rare. Vesicle, being of cell size, can be treated as a simple model of cell to investigate the behaviors of cell in electric field. Based on the finite element method, we investigate the effect of vesicle shape on electrofusion of contact vesicles in various medium conditions. The transmembrane voltage (TMV) and pore density induced by a pulsed field are examined to analyze the possibility of vesicle fusion. In two different medium conditions, the prolate shape is observed to have selective electroporation at the contact area of vesicles when the exterior conductivity is smaller than the interior one; selective electroporation is more inclined to be found at the poles of the oblate vesicles when the exterior conductivity is larger than the interior one. Furthermore, we find that when the exterior conductivity is lower than the internal conductivity, the pulse can induce a selective electroporation at the contact area between two vesicles regardless of the vesicle shape. Both of these two findings have important practical applications in guiding electrofusion experiments.

  13. Syncytiotrophoblast Extracellular Vesicles from Pre-Eclampsia Placentas Differentially Affect Platelet Function

    National Research Council Canada - National Science Library

    Tannetta, Dionne S; Hunt, Kathryn; Jones, Chris I; Davidson, Naomi; Coxon, Carmen H; Ferguson, David; Redman, Christopher W; Gibbins, Jonathan M; Sargent, Ian L; Tucker, Katherine L

    2015-01-01

    .... In PE, the failing endoplasmic reticulum, oxidative and inflammatory stressed syncytiotrophoblast layer of the placenta sheds increased numbers of syncytiotrophoblast extracellular vesicles (STBEV...

  14. α-Synuclein can inhibit SNARE-mediated vesicle fusion through direct interactions with lipid bilayers.

    Science.gov (United States)

    DeWitt, David C; Rhoades, Elizabeth

    2013-04-09

    The native function of α-synuclein is thought to involve regulation of synaptic vesicle trafficking. Recent work has also implicated a role in neurotransmission, possibly through interactions with the proteins involved in synaptic vesicle fusion. Here, we demonstrate that α-synuclein inhibits SNARE-mediated vesicle fusion through binding the membrane, without a direct interaction between α-synuclein and any of the SNARE proteins. This work supports a model in which α-synuclein plays a role in the regulation of vesicle fusion by modulating properties of the lipid bilayer.

  15. Phosphorylation of Synaptojanin Differentially Regulates Endocytosis of Functionally Distinct Synaptic Vesicle Pools.

    Science.gov (United States)

    Geng, Junhua; Wang, Liping; Lee, Joo Yeun; Chen, Chun-Kan; Chang, Karen T

    2016-08-24

    The rapid replenishment of synaptic vesicles through endocytosis is crucial for sustaining synaptic transmission during intense neuronal activity. Synaptojanin (Synj), a phosphoinositide phosphatase, is known to play an important role in vesicle recycling by promoting the uncoating of clathrin following synaptic vesicle uptake. Synj has been shown to be a substrate of the minibrain (Mnb) kinase, a fly homolog of the dual-specificity tyrosine phosphorylation-regulated kinase 1A (DYRK1A); however, the functional impacts of Synj phosphorylation by Mnb are not well understood. Here we identify that Mnb phosphorylates Synj at S1029 in Drosophila We find that phosphorylation of Synj at S1029 enhances Synj phosphatase activity, alters interaction between Synj and endophilin, and promotes efficient endocytosis of the active cycling vesicle pool (also referred to as exo-endo cycling pool) at the expense of reserve pool vesicle endocytosis. Dephosphorylated Synj, on the other hand, is deficient in the endocytosis of the active recycling pool vesicles but maintains reserve pool vesicle endocytosis to restore total vesicle pool size and sustain synaptic transmission. Together, our findings reveal a novel role for Synj in modulating reserve pool vesicle endocytosis and further indicate that dynamic phosphorylation and dephosphorylation of Synj differentially maintain endocytosis of distinct functional synaptic vesicle pools. Synaptic vesicle endocytosis sustains communication between neurons during a wide range of neuronal activities by recycling used vesicle membrane and protein components. Here we identify that Synaptojanin, a protein with a known role in synaptic vesicle endocytosis, is phosphorylated at S1029 in vivo by the Minibrain kinase. We further demonstrate that the phosphorylation status of Synaptojanin at S1029 differentially regulates its participation in the recycling of distinct synaptic vesicle pools. Our results reveal a new role for Synaptojanin in

  16. Quantitative analysis of vesicle recycling at the calyx of Held synapse

    Science.gov (United States)

    Qiu, Xufeng; Zhu, Qianwen; Sun, Jianyuan

    2015-01-01

    Vesicle recycling is pivotal for maintaining reliable synaptic signaling, but its basic properties remain poorly understood. Here, we developed an approach to quantitatively analyze the kinetics of vesicle recycling with exquisite signal and temporal resolution at the calyx of Held synapse. The combination of this electrophysiological approach with electron microscopy revealed that ∼80% of vesicles (∼270,000 out of ∼330,000) in the nerve terminal are involved in recycling. Under sustained stimulation, recycled vesicles start to be reused in tens of seconds when ∼47% of the preserved vesicles in the recycling pool (RP) are depleted. The heterogeneity of vesicle recycling as well as two kinetic components of RP depletion revealed the existence of a replenishable pool of vesicles before the priming stage and led to a realistic kinetic model that assesses the size of the subpools of the RP. Thus, our study quantified the kinetics of vesicle recycling and kinetically dissected the whole vesicle pool in the calyceal terminal into the readily releasable pool (∼0.6%), the readily priming pool (∼46%), the premature pool (∼33%), and the resting pool (∼20%). PMID:25825725

  17. A preliminary proteomic characterisation of extracellular vesicles released by the ovine parasitic nematode, Teladorsagia circumcincta.

    Science.gov (United States)

    Tzelos, Thomas; Matthews, Jacqueline B; Buck, Amy H; Simbari, Fabio; Frew, David; Inglis, Neil F; McLean, Kevin; Nisbet, Alasdair J; Whitelaw, C Bruce A; Knox, David P; McNeilly, Tom N

    2016-05-15

    Teladorsagia circumcincta is a major cause of ovine parasitic gastroenteritis in temperate climatic regions. The development of high levels of anthelmintic resistance in this nematode species challenges its future control. Recent research indicates that many parasite species release extracellular vesicles into their environment, many of which have been classified as endocytic in origin, termed exosomes. These vesicles are considered to play important roles in the intercellular communication between parasites and their hosts, and thus represent potentially useful targets for novel control strategies. Here, we demonstrate that exosome-like extracellular vesicles can be isolated from excretory-secretory (ES) products released by T. circumcincta fourth stage larvae (Tci-L4ES). Furthermore, we perform a comparative proteomic analysis of vesicle-enriched and vesicle-free Tci-L4ES. Approximately 73% of the proteins identified in the vesicle-enriched fraction were unique to this fraction, whilst the remaining 27% were present in both vesicle-enriched and vesicle-free fraction. These unique proteins included structural proteins, nuclear proteins, metabolic proteins, proteolytic enzymes and activation-associated secreted proteins. Finally, we demonstrate that molecules present within the vesicles-enriched material are targets of the IgA and IgG response in T. circumcincta infected sheep, and could potentially represent useful targets for future vaccine intervention studies. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Identification of EDIL3 on extracellular vesicles involved in breast cancer cell invasion.

    Science.gov (United States)

    Lee, Jeong-Eun; Moon, Pyong-Gon; Cho, Young-Eun; Kim, Young-Bum; Kim, In-San; Park, Hoyong; Baek, Moon-Chang

    2016-01-10

    Cancer cell-derived extracellular vesicles have been linked to the pathogenesis of various cancers; however, the role of extracellular vesicles in tumorigenesis remains unclear. To identify extracellular vesicle proteins involved in cancer metastasis, quantitative proteomic analyses were performed on extracellular vesicles derived from two representative breast cancer cell lines: the less invasive MCF-7 and the invasive MDA-MB-231. Proteomic analysis allowed for the identification of 270 proteins in the extracellular vesicles. Here we report a new function of EDIL3 on extracellular vesicles, which are sufficient for enhancement of cell invasion and for acceleration of lung metastasis in vivo. This invasion is most likely mediated via the integrin-FAK signaling cascade in breast cancer cells. However, these effects are suppressed when EDIL3 is inactivated, providing evidence for a critical role of EDIL3 in development of cancer. Consistently, in human patients with metastatic breast cancer, the levels of EDIL3 on circulating extracellular vesicles are significantly elevated. This information is a remarkable breakthrough in understanding of the molecular mechanism underlying metastasis of breast cancer as well as in the research for cancer biomarkers using circulating extracellular vesicles. Furthermore, targeting EDIL3 on extracellular vesicles may lead to a new therapeutic option for treatment of breast cancer. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. Antibody Binding Alters the Characteristics and Contents of Extracellular Vesicles Released by Histoplasma capsulatum.

    Science.gov (United States)

    Matos Baltazar, Ludmila; Nakayasu, Ernesto S; Sobreira, Tiago J P; Choi, Hyungwon; Casadevall, Arturo; Nimrichter, Leonardo; Nosanchuk, Joshua D

    2016-01-01

    Histoplasma capsulatum produces extracellular vesicles containing virulence-associated molecules capable of modulating host machinery, benefiting the pathogen. Treatment of H. capsulatum cells with monoclonal antibodies (MAbs) can change the outcome of infection in mice. We evaluated the sizes, enzymatic contents, and proteomic profiles of the vesicles released by fungal cells treated with either protective MAb 6B7 (IgG1) or nonprotective MAb 7B6 (IgG2b), both of which bind H. capsulatum heat shock protein 60 (Hsp60). Our results showed that treatment with either MAb was associated with changes in size and vesicle loading. MAb treatments reduced vesicle phosphatase and catalase activities compared to those of vesicles from untreated controls. We identified 1,125 proteins in vesicles, and 250 of these manifested differences in abundance relative to that of proteins in vesicles isolated from yeast cells exposed to Hsp60-binding MAbs, indicating that surface binding of fungal cells by MAbs modified protein loading in the vesicles. The abundance of upregulated proteins in vesicles upon MAb 7B6 treatment was 44.8% of the protein quantities in vesicles from fungal cells treated with MAb 6B7. Analysis of orthologous proteins previously identified in vesicles from other fungi showed that different ascomycete fungi have similar proteins in their extracellular milieu, many of which are associated with virulence. Our results demonstrate that antibody binding can modulate fungal cell responses, resulting in differential loading of vesicles, which could alter fungal cell susceptibility to host defenses. This finding provides additional evidence that antibody binding modulates microbial physiology and suggests a new function for specific immunoglobulins through alterations of fungal secretion. IMPORTANCE Diverse fungal species release extracellular vesicles, indicating that this is a common pathway for the delivery of molecules to the extracellular space. However, there has

  20. Extracellular vesicles: An overview of biogenesis, function, and role in breast cancer.

    Science.gov (United States)

    Zha, Quan Bin; Yao, Yu Feng; Ren, Zhao Jun; Li, Xiu Juan; Tang, Jin Hai

    2017-02-01

    Extracellular vesicles have emerged as important mediators of intercellular communication and play an active role in cancer, including breast cancer. Despite limited studies, initial observations suggest that these vesicles are important in breast physiology and pathophysiology. We here, in brief, describe their potential use as future biomarkers and therapeutic agents in breast cancer. Extracellular vesicles in blood and breast fluid may have a great potential to detect and predict the presence of breast cancer, and extracellular vesicles modulation may emerge as a therapeutic approach in cancer therapy.

  1. Isolation and characterization of urinary extracellular vesicles: implications for biomarker discovery.

    Science.gov (United States)

    Merchant, Michael L; Rood, Ilse M; Deegens, Jeroen K J; Klein, Jon B

    2017-12-01

    Urine is a valuable diagnostic medium and, with the discovery of urinary extracellular vesicles, is viewed as a dynamic bioactive fluid. Extracellular vesicles are lipid-enclosed structures that can be classified into three categories: exosomes, microvesicles (or ectosomes) and apoptotic bodies. This classification is based on the mechanisms by which membrane vesicles are formed: fusion of multivesicular bodies with the plasma membranes (exosomes), budding of vesicles directly from the plasma membrane (microvesicles) or those shed from dying cells (apoptotic bodies). During their formation, urinary extracellular vesicles incorporate various cell-specific components (proteins, lipids and nucleic acids) that can be transferred to target cells. The rigour needed for comparative studies has fueled the search for optimal approaches for their isolation, purification, and characterization. RNA, the newest extracellular vesicle component to be discovered, has received substantial attention as an extracellular vesicle therapeutic, and compelling evidence suggests that ex vivo manipulation of microRNA composition may have uses in the treatment of kidney disorders. The results of these studies are building the case that urinary extracellular vesicles act as mediators of renal pathophysiology. As the field of extracellular vesicle studies is burgeoning, this Review focuses on primary data obtained from studies of human urine rather than on data from studies of laboratory animals or cultured immortalized cells.

  2. Nonmuscle Myosin II helps regulate synaptic vesicle mobility at the Drosophila neuromuscular junction

    Directory of Open Access Journals (Sweden)

    Qiu Xinping

    2010-03-01

    Full Text Available Abstract Background Although the mechanistic details of the vesicle transport process from the cell body to the nerve terminal are well described, the mechanisms underlying vesicle traffic within nerve terminal boutons is relatively unknown. The actin cytoskeleton has been implicated but exactly how actin or actin-binding proteins participate in vesicle movement is not clear. Results In the present study we have identified Nonmuscle Myosin II as a candidate molecule important for synaptic vesicle traffic within Drosophila larval neuromuscular boutons. Nonmuscle Myosin II was found to be localized at the Drosophila larval neuromuscular junction; genetics and pharmacology combined with the time-lapse imaging technique FRAP were used to reveal a contribution of Nonmuscle Myosin II to synaptic vesicle movement. FRAP analysis showed that vesicle dynamics were highly dependent on the expression level of Nonmuscle Myosin II. Conclusion Our results provide evidence that Nonmuscle Myosin II is present presynaptically, is important for synaptic vesicle mobility and suggests a role for Nonmuscle Myosin II in shuttling vesicles at the Drosophila neuromuscular junction. This work begins to reveal the process by which synaptic vesicles traverse within the bouton.

  3. Effects of deuterium oxide on cell growth and vesicle speed in RBL-2H3 cells

    Directory of Open Access Journals (Sweden)

    Roshni S. Kalkur

    2014-09-01

    Full Text Available For the first time we show the effects of deuterium oxide on cell growth and vesicle transport in rat basophilic leukemia (RBL-2H3 cells. RBL-2H3 cells cultured with 15 moles/L deuterium showed decreased cell growth which was attributed to cells not doubling their DNA content. Experimental observations also showed an increase in vesicle speed for cells cultured in deuterium oxide. This increase in vesicle speed was not observed in deuterium oxide cultures treated with a microtubule-destabilizing drug, suggesting that deuterium oxide affects microtubule-dependent vesicle transport.

  4. Isolation and characterization of platelet-derived extracellular vesicles

    Directory of Open Access Journals (Sweden)

    Maria T. Aatonen

    2014-08-01

    Full Text Available Background: Platelet-derived extracellular vesicles (EVs participate, for example, in haemostasis, immunity and development. Most studies of platelet EVs have targeted microparticles, whereas exosomes and EV characterization under various conditions have been less analyzed. Studies have been hampered by the difficulty in obtaining EVs free from contaminating cells and platelet remnants. Therefore, we optimized an EV isolation protocol and compared the quantity and protein content of EVs induced by different agonists. Methods: Platelets isolated with iodixanol gradient were activated by thrombin and collagen, lipopolysaccharide (LPS or Ca2+ ionophore. Microparticles and exosomes were isolated by differential centrifugations. EVs were quantitated by nanoparticle tracking analysis (NTA and total protein. Size distributions were determined by NTA and electron microscopy. Proteomics was used to characterize the differentially induced EVs. Results: The main EV populations were 100–250 nm and over 90% were <500 nm irrespective of the activation. However, activation pathways differentially regulated the quantity and the quality of EVs, which also formed constitutively. Thrombogenic activation was the most potent physiological EV-generator. LPS was a weak inducer of EVs, which had a selective protein content from the thrombogenic EVs. Ca2+ ionophore generated a large population of protein-poor and unselectively packed EVs. By proteomic analysis, EVs were highly heterogeneous after the different activations and between the vesicle subpopulations. Conclusions: Although platelets constitutively release EVs, vesiculation can be increased, and the activation pathway determines the number and the cargo of the formed EVs. These activation-dependent variations render the use of protein content in sample normalization invalid. Since most platelet EVs are 100–250 nm, only a fraction has been analyzed by previously used methods, for example, flow cytometry. As

  5. Shapes and singularities in triatic liquid-crystal vesicles

    Science.gov (United States)

    Bowick, Mark J.; Manyuhina, O. V.; Serafin, F.

    2017-01-01

    Determining the equilibrium configuration and shape of curved two-dimensional films with (generalized) liquid-crystalline order is a difficult infinite-dimensional problem of direct relevance to the study of generalized polymersomes, soft matter and the fascinating problem of understanding the origin and formation of shape (morphogenesis). The symmetry of the free energy of the LC film being considered and the topology of the surface to be determined often requires that the equilibrium configuration possesses singular structures in the form of topological defects such as disclinations for nematic films. The precise number and type of defect plays a fundamental role in restricting the space of possible equilibrium shapes. Flexible closed vesicles with spherical topology and nematic or smectic order, for example, inevitably possess four elementary strength +1/2 disclination defects positioned at the four vertices of a tetrahedral shell. Here we address the problem of determining the equilibrium shape of flexible vesicles with generalized liquid-crystalline order. The order parameter in these cases is an element of S^1/Zp , for any positive integer p. We will focus on the case p =3 , known as triatic liquid crystals (LCs). We construct the appropriate order parameter for triatics and find the associated free energy. We then describe the structure of the elementary defects of strength +1/3 in flat space. Finally, we prove that sufficiently floppy triatic vesicles with the topology of the 2-sphere equilibrate to octahedral shells with strength +1/3 defects at each of the six vertices, independently of the scale.

  6. Synaptic vesicle dynamic changes in a model of fragile X.

    Science.gov (United States)

    Broek, Jantine A C; Lin, Zhanmin; de Gruiter, H Martijn; van 't Spijker, Heleen; Haasdijk, Elize D; Cox, David; Ozcan, Sureyya; van Cappellen, Gert W A; Houtsmuller, Adriaan B; Willemsen, Rob; de Zeeuw, Chris I; Bahn, Sabine

    2016-01-01

    Fragile X syndrome (FXS) is a single-gene disorder that is the most common heritable cause of intellectual disability and the most frequent monogenic cause of autism spectrum disorders (ASD). FXS is caused by an expansion of trinucleotide repeats in the promoter region of the fragile X mental retardation gene (Fmr1). This leads to a lack of fragile X mental retardation protein (FMRP), which regulates translation of a wide range of messenger RNAs (mRNAs). The extent of expression level alterations of synaptic proteins affected by FMRP loss and their consequences on synaptic dynamics in FXS has not been fully investigated. Here, we used an Fmr1 knockout (KO) mouse model to investigate the molecular mechanisms underlying FXS by monitoring protein expression changes using shotgun label-free liquid-chromatography mass spectrometry (LC-MS(E)) in brain tissue and synaptosome fractions. FXS-associated candidate proteins were validated using selected reaction monitoring (SRM) in synaptosome fractions for targeted protein quantification. Furthermore, functional alterations in synaptic release and dynamics were evaluated using live-cell imaging, and interpretation of synaptic dynamics differences was investigated using electron microscopy. Key findings relate to altered levels of proteins involved in GABA-signalling, especially in the cerebellum. Further exploration using microscopy studies found reduced synaptic vesicle unloading of hippocampal neurons and increased vesicle unloading in cerebellar neurons, which suggests a general decrease of synaptic transmission. Our findings suggest that FMRP is a regulator of synaptic vesicle dynamics, which supports the role of FMRP in presynaptic functions. Taken together, these studies provide novel insights into the molecular changes associated with FXS.

  7. A Patient with MSUD: Acute Management with Sodium Phenylacetate/Sodium Benzoate and Sodium Phenylbutyrate

    OpenAIRE

    Melis Köse; Ebru Canda; Mehtap Kagnici; Sema Kalkan Uçar; Mahmut Çoker

    2017-01-01

    In treatment of metabolic imbalances caused by maple syrup urine disease (MSUD), peritoneal dialysis, and hemofiltration, pharmacological treatments for elimination of toxic metabolites can be used in addition to basic dietary modifications. Therapy with sodium phenylacetate/benzoate or sodium phenylbutyrate (NaPB) in urea-cycle disorder cases has been associated with a reduction in branched-chain amino acid (BCAA) concentrations when the patients are on adequate dietary protein intake. Moreo...

  8. Miscibility Phase Diagrams of Giant Vesicles Containing Sphingomyelin

    Science.gov (United States)

    Veatch, Sarah L.; Keller, Sarah L.

    2005-04-01

    Saturated sphingomyelin (SM) lipids are implicated in lipid rafts in cell plasma membranes. Here we use fluorescence microscopy to observe coexisting liquid domains in vesicles containing SM, an unsaturated phosphatidylcholine lipid (either DOPC or POPC), and cholesterol. We note similar phase behavior in a model membrane mixture without SM (DOPC/DPPC/Chol), but find no micron-scale liquid domains in membranes of POPC/PSM/Chol. We delineate the onset of solid phases below the miscibility transition temperature, and detail indirect evidence for a three-phase coexistence of one solid and two liquid phases.

  9. Phase transitions in methyl parben doped dipalmitoyl phosphatidylethanolamine vesicles

    Science.gov (United States)

    Panicker, Lata

    2013-02-01

    Influence of the preservative, methyl paraben (MPB), on the thermal properties of dipalmitoyl phosphatidylethanolamine (DPPE) vesicles was investigated using DSC. DSC measurement of the lipid acyl chain melting transition in DPPE membrane doped with MPB, showed MPB concentration dependant modifications in the membrane thermal properties. The interesting findings are: (1) the presence of parabens increases the membrane fluidity. (2) the MPB molecules seem to be present in the aqueous bilayer interfacial region intercalated between the neighboring lipid polar headgroup (3) high concentration of MPB favored formation of crystalline and glassy phases.

  10. Time-resolved SERS for characterizing extracellular vesicles

    Science.gov (United States)

    Rojalin, Tatu; Saari, Heikki; Somersalo, Petter; Laitinen, Saara; Turunen, Mikko; Viitala, Tapani; Wachsmann-Hogiu, Sebastian; Smith, Zachary J.; Yliperttula, Marjo

    2017-02-01

    The aim of this work is to develop a platform for characterizing extracellular vesicles (EV) by using gold-polymer nanopillar SERS arrays simultaneously circumventing the photoluminescence-related disadvantages of Raman with a time-resolved approach. EVs are rich of biochemical information reporting of, for example, diseased state of the biological system. Currently, straightforward, label-free and fast EV characterization methods with low sample consumption are warranted. In this study, SERS spectra of red blood cell and platelet derived EVs were successfully measured and their biochemical contents analyzed using multivariate data analysis techniques. The developed platform could be conveniently used for EV analytics in general.

  11. Extracellular Vesicles in Heart Disease: Excitement for the Future?

    Directory of Open Access Journals (Sweden)

    Kirsty M. Danielson

    2014-01-01

    Full Text Available Extracellular vesicles (EV, including exosomes, microvesicles and apoptotic bodies, are released from numerous cell types and are involved in intercellular communication, physiological functions and the pathology of disease. They have been shown to carry and transfer a wide range of cargo including proteins, lipids and nucleic acids. The role of EVs in cardiac physiology and heart disease is an emerging field that has produced intriguing findings in recent years. This review will outline what is currently known about EVs in the cardiovascular system, including cellular origins, functional roles and utility as biomarkers and potential therapeutics.

  12. Potential Roles of Fungal Extracellular Vesicles during Infection

    Science.gov (United States)

    Joffe, Luna S.; Nimrichter, Leonardo

    2016-01-01

    ABSTRACT Extracellular vesicles (EVs) are produced by virtually all cell types. Within the past few years, work in this field has revealed more information about fungal EVs. Fungal EVs have been shown to carry proteins, lipids, pigments, polysaccharides, and RNA; these components are known virulence factors, a fact which supports the hypothesis that fungal EVs concentrate pathogenic determinants. Additionally, recent studies have demonstrated that fungal EVs stimulate the host immune system. In this review, putative roles of fungal EVs are discussed, including their potential as vaccination tools and their possible contribution to pathogenesis in invasive fungal diseases. PMID:27390779

  13. Tension-induced vesicle fusion: pathways and pore dynamics

    DEFF Research Database (Denmark)

    Shillcock, Julian C.

    2008-01-01

    and eventually opens a pore to complete the fusion process. In pathway II, at higher tension, a stalk is formed during the fusion process that is then transformed by transmembrane pore formation into a fusion pore. Whereas the latter pathway II resembles stalk pathways as observed in other simulation studies......, fusion pathway I, which does not involve any stalk formation, has not been described previously to the best of our knowledge. A statistical analysis of the various processes shows that fusion is the dominant pathway for releasing the tension of the vesicles. The functional dependence of the observed...

  14. On the growth of walled cells: From shells to vesicles.

    Science.gov (United States)

    Boudaoud, Arezki

    2003-03-01

    The growth of isolated walled cells is investigated. Examples of such cells range from bacteria to giant algae, and include cochlear hair, plant root hair, fungi and yeast cells. They are modeled as elastic shells inflated by a liquid. Cell growth is driven by fluid pressure and is similar to a plastic deformation of the wall. The requirement of mechanical equilibrium leads to two new scaling laws for cell size that are in quantitative agreement with the compiled biological data. Given these results, possible shapes for growing cells are computed by analogy with those of vesicle membranes.

  15. Growth of Walled Cells: From Shells to Vesicles

    Science.gov (United States)

    Boudaoud, Arezki

    2003-07-01

    The growth of isolated walled cells is investigated. Examples of such cells range from bacteria to giant algae, and include cochlear hair, plant root hair, fungi, and yeast cells. They are modeled as elastic shells containing a liquid. Cell growth is driven by fluid pressure and is is similar to a plastic deformation of the wall. The requirement of mechanical equilibrium leads to two new scaling laws for cell size that are in quantitative agreement with the compiled biological data. Given these results, possible shapes for growing cells are computed by analogy with those of vesicle membranes.

  16. Insect sodium channels and insecticide resistance

    OpenAIRE

    Dong, Ke

    2007-01-01

    Voltage-gated sodium channels are essential for the generation and propagation of action potentials (i.e., electrical impulses) in excitable cells. Although most of our knowledge about sodium channels is derived from decades of studies of mammalian isoforms, research on insect sodium channels is revealing both common and unique aspects of sodium channel biology. In particular, our understanding of the molecular dynamics and pharmacology of insect sodium channels has advanced greatly in recent...

  17. Sodium Velocity Maps on Mercury

    Science.gov (United States)

    Potter, A. E.; Killen, R. M.

    2011-01-01

    The objective of the current work was to measure two-dimensional maps of sodium velocities on the Mercury surface and examine the maps for evidence of sources or sinks of sodium on the surface. The McMath-Pierce Solar Telescope and the Stellar Spectrograph were used to measure Mercury spectra that were sampled at 7 milliAngstrom intervals. Observations were made each day during the period October 5-9, 2010. The dawn terminator was in view during that time. The velocity shift of the centroid of the Mercury emission line was measured relative to the solar sodium Fraunhofer line corrected for radial velocity of the Earth. The difference between the observed and calculated velocity shift was taken to be the velocity vector of the sodium relative to Earth. For each position of the spectrograph slit, a line of velocities across the planet was measured. Then, the spectrograph slit was stepped over the surface of Mercury at 1 arc second intervals. The position of Mercury was stabilized by an adaptive optics system. The collection of lines were assembled into an images of surface reflection, sodium emission intensities, and Earthward velocities over the surface of Mercury. The velocity map shows patches of higher velocity in the southern hemisphere, suggesting the existence of sodium sources there. The peak earthward velocity occurs in the equatorial region, and extends to the terminator. Since this was a dawn terminator, this might be an indication of dawn evaporation of sodium. Leblanc et al. (2008) have published a velocity map that is similar.

  18. Two barriers for sodium in vascular endothelium?

    Science.gov (United States)

    Oberleithner, Hans

    2012-01-01

    Vascular endothelium plays a key role in blood pressure regulation. Recently, it has been shown that a 5% increase of plasma sodium concentration (sodium excess) stiffens endothelial cells by about 25%, leading to cellular dysfunction. Surface measurements demonstrated that the endothelial glycocalyx (eGC), an anionic biopolymer, deteriorates when sodium is elevated. In view of these results, a two-barrier model for sodium exiting the circulation across the endothelium is suggested. The first sodium barrier is the eGC which selectively buffers sodium ions with its negatively charged prote-oglycans.The second sodium barrier is the endothelial plasma membrane which contains sodium channels. Sodium excess, in the presence of aldosterone, leads to eGC break-down and, in parallel, to an up-regulation of plasma membrane sodium channels. The following hypothesis is postulated: Sodium excess increases vascular sodium permeability. Under such con-ditions (e.g. high-sodium diet), day-by-day ingested sodium, instead of being readily buffered by the eGC and then rapidly excreted by the kidneys, is distributed in the whole body before being finally excreted. Gradually, the sodium overload damages the organism. PMID:22471931

  19. Differential regulation of synaptic vesicle tethering and docking by UNC-18 and TOM-1

    Directory of Open Access Journals (Sweden)

    Elena O Gracheva

    2010-10-01

    Full Text Available The assembly of SNARE complexes between syntaxin, SNAP-25 and synaptobrevin is required to prime synaptic vesicles for fusion. Since Munc18 and tomosyn compete for syntaxin interactions, the interplay between these proteins is predicted to be important in regulating synaptic transmission. We explored this possibility, by examining genetic interactions between C. elegans unc-18(Munc18, unc-64(syntaxin and tom-1(tomosyn. We have previously demonstrated that unc-18 mutants have reduced synaptic transmission, whereas tom-1 mutants exhibit enhanced release. Here we show that the unc-18 mutant release defect is associated with loss of two morphologically distinct vesicle pools; those tethered within 25nm of the plasma membrane and those docked with the plasma membrane. In contrast, priming defective unc-13 mutants accumulate tethered vesicles, while docked vesicles are greatly reduced, indicating tethering is UNC-18-dependent and occurs in the absence of priming. C. elegans unc-64 mutants phenocopy unc-18 mutants, losing both tethered and docked vesicles, whereas overexpression of open syntaxin preferentially increases vesicle docking, suggesting UNC-18/closed syntaxin interactions are responsible for vesicle tethering. Given the competition between vertebrate tomosyn and Munc18, for syntaxin binding, we hypothesized that C. elegans TOM-1 may inhibit both UNC-18-dependent vesicle targeting steps. Consistent with this hypothesis, tom-1 mutants exhibit enhanced UNC-18 plasma membrane localization and a concomitant increase in both tethered and docked synaptic vesicles. Furthermore, in tom-1;unc-18 double mutants the docked, primed vesicle pool is preferentially rescued relative to unc-18 single mutants. Together these data provide evidence for the differential regulation of two vesicle targeting steps by UNC-18 and TOM-1 through competitive interactions with syntaxin

  20. Characterization of an additional articular cartilage vesicle fraction that generates calcium pyrophosphate dihydrate crystals in vitro.

    Science.gov (United States)

    Derfus, B; Steinberg, M; Mandel, N; Buday, M; Daft, L; Ryan, L

    1995-08-01

    We previously identified a unique fraction of porcine articular cartilage vesicles, sedimentable at 8 x 10(6) g/min, which generate calcium pyrophosphate dihydrate crystals (CPPD) in vitro. We sought to identify and characterize other fractions of articular cartilage digest, sedimentable at lower g forces, which may also contain mineralizing vesicles. Electron microscopy and alkaline phosphatase and nucleoside triphosphate pyrophosphohydrolase (NTPPPH) assays were used to analyze each fraction. Radiometric mineralization assays, Fourier transform infrared (FTIR) spectroscopy, and compensated polarized light microscopy were used to analyze crystals formed by these fractions. Vesicles of varying sizes identical to epiphyseal cartilage matrix vesicles were seen in all sedimentable fractions examined, but were the exclusive component of fractions sedimentable at 3 x 10(6) g/min, termed the heavy vesicle fraction (HVF), and at 8 x 10(6) g/min, now termed the light vesicle fraction (LVF). All vesicle containing fractions supported ATP dependent calcium pyrophosphate precipitation. The HVF and LVF precipitated 30 x more calcium than vesicle poor supernatant (p < 0.01) and 1.5-4 x more than cell-free unfractionated digest (p < 0.01). HVF differed from LVF in that it contained 3-4 x higher NTPPPH specific activity (p < 0.05). HVF resembled LVF in that both precipitated crystals consistent with CPPD by FTIR spectroscopy and compensated polarized light microscopy. These data expand our previous estimate of the total number of vesicles available for biologic mineralization and demonstrate heterogeneity of vesicle fractions. They support a key role for vesicles in CPPD crystal formation.

  1. Composition Effect of the Outer Layer on the Vesicle Fusion Catalyzed by Phospholipase D

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jin Won [Seoul National University, Seoul (Korea, Republic of)

    2014-09-15

    Phospholipase D (PLD) catalyzed the generation of phosphatidic acid (PA) from phosphatidylcholine (PC) at the outer layer of the vesicles prepared through layer by layer via a double emulsion technique. The generation induced a curvature change in the vesicles, which eventually led them to fuse each other. The ratio of two-fattyacid-tail ethanolamine (PE) to one-fatty-acid-tail ethanolamine (PE) was found to acquire the condition where the mixed-phospholipid vesicles were stable identically with pure two-fatty-acid-tail PC. The effect of the outer-layer mixture on the PLD-induced vesicle fusion was investigated using the fluorescence intensity change. 8-Aminonaph- thalene-1,3,6-trisulfonic acid disodium salt (ANTS) and p-Xylene-bis(N-pyridinium bromide) (DPX) were encapsulated in the vesicles, respectively, for the quantification of the fusion. The fluorescence scale was calibrated with the fluorescence of a 1/1 mixture of ANTS and DPX vesicles in NaCl buffer taken as 100% fluorescence (0% fusion) and the vesicles containing both ANTS and DPX as 0% fluorescence (100% fusion), considering the leakage into the medium studied directly in a separate experiment using vesicles containing both ANTS and DPX. The fusion data for each composition were acquired with the subtraction of the leakage from the quenching. From the monitoring, the vesicle fusion caused by the PLD reaction seems dominantly to occur rather than the vesicle lysis, because the composition effect on the fusion was observed identically with that on the change in the vesicle structure. Furthermore, the diameter measurements also support the fusion dominancy.

  2. Methods for the physical characterization and quantification of extracellular vesicles in biological samples.

    Science.gov (United States)

    Rupert, Déborah L M; Claudio, Virginia; Lässer, Cecilia; Bally, Marta

    2017-01-01

    Our body fluids contain a multitude of cell-derived vesicles, secreted by most cell types, commonly referred to as extracellular vesicles. They have attracted considerable attention for their function as intercellular communication vehicles in a broad range of physiological processes and pathological conditions. Extracellular vesicles and especially the smallest type, exosomes, have also generated a lot of excitement in view of their potential as disease biomarkers or as carriers for drug delivery. In this context, state-of-the-art techniques capable of comprehensively characterizing vesicles in biological fluids are urgently needed. This review presents the arsenal of techniques available for quantification and characterization of physical properties of extracellular vesicles, summarizes their working principles, discusses their advantages and limitations and further illustrates their implementation in extracellular vesicle research. The small size and physicochemical heterogeneity of extracellular vesicles make their physical characterization and quantification an extremely challenging task. Currently, structure, size, buoyant density, optical properties and zeta potential have most commonly been studied. The concentration of vesicles in suspension can be expressed in terms of biomolecular or particle content depending on the method at hand. In addition, common quantification methods may either provide a direct quantitative measurement of vesicle concentration or solely allow for relative comparison between samples. The combination of complementary methods capable of detecting, characterizing and quantifying extracellular vesicles at a single particle level promises to provide new exciting insights into their modes of action and to reveal the existence of vesicle subpopulations fulfilling key biological tasks. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. Characterisation of adipocyte-derived extracellular vesicle subtypes identifies distinct protein and lipid signatures for large and small extracellular vesicles.

    Science.gov (United States)

    Durcin, Maëva; Fleury, Audrey; Taillebois, Emiliane; Hilairet, Grégory; Krupova, Zuzana; Henry, Céline; Truchet, Sandrine; Trötzmüller, Martin; Köfeler, Harald; Mabilleau, Guillaume; Hue, Olivier; Andriantsitohaina, Ramaroson; Martin, Patrice; Le Lay, Soazig

    2017-01-01

    Extracellular vesicles (EVs) are biological vectors that can modulate the metabolism of target cells by conveying signalling proteins and genomic material. The level of EVs in plasma is significantly increased in cardiometabolic diseases associated with obesity, suggesting their possible participation in the development of metabolic dysfunction. With regard to the poor definition of adipocyte-derived EVs, the purpose of this study was to characterise both qualitatively and quantitatively EVs subpopulations secreted by fat cells. Adipocyte-derived EVs were isolated by differential centrifugation of conditioned media collected from 3T3-L1 adipocytes cultured for 24 h in serum-free conditions. Based on morphological and biochemical properties, as well as quantification of secreted EVs, we distinguished two subpopulations of adipocyte-derived EVs, namely small extracellular vesicles (sEVs) and large extracellular vesicles (lEVs). Proteomic analyses revealed that lEVs and sEVs exhibit specific protein signatures, allowing us not only to define novel markers of each population, but also to predict their biological functions. Despite similar phospholipid patterns, the comparative lipidomic analysis performed on these EV subclasses revealed a specific cholesterol enrichment of the sEV population, whereas lEVs were characterised by high amounts of externalised phosphatidylserine. Enhanced secretion of lEVs and sEVs is achievable following exposure to different biological stimuli related to the chronic low-grade inflammation state associated with obesity. Finally, we demonstrate the ability of primary murine adipocytes to secrete sEVs and lEVs, which display physical and biological characteristics similar to those described for 3T3-L1. Our study provides additional information and elements to define EV subtypes based on the characterisation of adipocyte-derived EV populations. It also underscores the need to distinguish EV subpopulations, through a combination of multiple

  4. Salmonella Choleraesuis outer membrane vesicles: Proteomics and immunogenicity.

    Science.gov (United States)

    Liu, Qiong; Yi, Jie; Liang, Kang; Zhang, Xiangmin; Liu, Qing

    2017-10-01

    Salmonella enterica serotype Choleraesuis (S. Choleraesuis), Gram-negative facultative intracellular pathogen is capable of inducing the cholera in pigs whose symptoms manifest as fever, depression, septicemia, arthritis, and diarrhea. Infections with S. Choleraesuis has resulted in great economic loss for the swine breeding operations. Bacterial outer membrane vesicles (OMVs) play an important role in pathogenicity and host-pathogen interaction. In this study, we purified OMVs released by S. Choleraesuis strain χ3545 and characterized their lipopolysaccharide (LPS) profile. The OMVs contained intact LPS molecules. By using LC-MS/MS, we identified 192 proteins in the OMVs. In addition, the subcellular location and biological functions of the vesicles was predicted. The proteins were mainly derived from outer membranes and cytoplasm. Several proteins were immunoreactive and associated with the secretion pathway. Some putative multi-drug resistance-associated proteins were also identified. Furthermore, immunization experiment via intranasal or intraperitoneal route in mice demonstrated that S. Choleraesuis OMVs could elicit strong humoral and mucosal immune responses. Although OMVs as vaccine did not provide strong protection against clinical strain of wild-type S. Choleraesuis, immunization of OMVs still prolonged the survival time of vaccinated mice after high dose of S. Choleraesuis infection. Overall, this study provides valuable fundamental information toward elucidating the pathogenicity and functions of OMVs secreted from S. Choleraesuis. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Extracellular vesicles in the pathogenesis of rheumatoid arthritis and osteoarthritis.

    Science.gov (United States)

    Withrow, Joseph; Murphy, Cameron; Liu, Yutao; Hunter, Monte; Fulzele, Sadanand; Hamrick, Mark W

    2016-12-01

    Osteoarthritis (OA) and rheumatoid arthritis (RA) are both debilitating diseases that cause significant morbidity in the US population. Extracellular vesicles (EVs), including exosomes and microvesicles, are now recognized to play important roles in cell-to-cell communication by transporting various proteins, microRNAs (miRNAs), and mRNAs. EV-derived proteins and miRNAs impact cell viability and cell differentiation, and are likely to play a prominent role in the pathophysiology of both OA and RA. Some of the processes by which these membrane-bound vesicles can alter joint tissue include extracellular matrix degradation, cell-to-cell communication, modulation of inflammation, angiogenesis, and antigen presentation. For example, EVs from IL-1β-stimulated fibroblast-like synoviocytes have been shown to induce osteoarthritic changes in chondrocytes. RA models have shown that EVs stimulated with inflammatory cytokines are capable of inducing apoptosis resistance in T cells, presenting antigen to T cells, and causing extracellular damage with matrix-degrading enzymes. EVs derived from rheumatoid models have also been shown to induce secretion of COX-2 and stimulate angiogenesis. Additionally, there is evidence that synovium-derived EVs may be promising biomarkers of disease in both OA and RA. The characterization of EVs in the joint space has also opened up the possibility for delivery of small molecules. This article reviews current knowledge on the role of EVs in both RA and OA, and their potential role as therapeutic targets for modulation of these debilitating diseases.

  6. Extracellular Vesicles: Evolving Factors in Stem Cell Biology

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    Muhammad Nawaz

    2016-01-01

    Full Text Available Stem cells are proposed to continuously secrete trophic factors that potentially serve as mediators of autocrine and paracrine activities, associated with reprogramming of the tumor microenvironment, tissue regeneration, and repair. Hitherto, significant efforts have been made to understand the level of underlying paracrine activities influenced by stem cell secreted trophic factors, as little is known about these interactions. Recent findings, however, elucidate this role by reporting the effects of stem cell derived extracellular vesicles (EVs that mimic the phenotypes of the cells from which they originate. Exchange of genetic information utilizing persistent bidirectional communication mediated by stem cell-EVs could regulate stemness, self-renewal, and differentiation in stem cells and their subpopulations. This review therefore discusses stem cell-EVs as evolving communication factors in stem cell biology, focusing on how they regulate cell fates by inducing persistent and prolonged genetic reprogramming of resident cells in a paracrine fashion. In addition, we address the role of stem cell-secreted vesicles in shaping the tumor microenvironment and immunomodulation and in their ability to stimulate endogenous repair processes during tissue damage. Collectively, these functions ensure an enormous potential for future therapies.

  7. Extracellular vesicles as therapeutic tools in cardiovascular diseases

    Directory of Open Access Journals (Sweden)

    Audrey eFleury

    2014-08-01

    Full Text Available Extracellular vesicles (EVs, including microvesicles (MVs and exosomes, are small vesicles secreted from a wide variety of cells. Whereas MVs are particles released by the outward budding of the plasma membrane, exosomes are derived from endocytic compartments. Secretion of EVs can be enhanced by specific stimuli, and increased plasma circulating levels of EVs have been correlated with pathophysiological situations.MVs, already present in the blood of healthy individuals, are considerably elevated in several cardiovascular diseases associated with inflammation, suggesting that they can mediate deleterious effects such as endothelial dysfunction or thrombosis. Nonetheless, very recent studies also demonstrate that MVs may act as biological information vectors transferring proteins or genetic material to maintain cell homeostasis, favor cell repair or even promote angiogenesis. Additionally, exosomes have also been shown to have proangiogenic and cardioprotective properties. These beneficial effects therefore reveal the potential therapeutical use of EVs in the field of cardiovascular medicine and regenerative therapy.In this review, we will provide an update of cellular processes modulated by EVs of specific interest in the treatment of cardiovascular pathologies. A special focus will be made on the morphogen sonic hedgehog (Shh associated with EVs (EVsShh+, which have been shown to mediate many pro-angiogenic effects. In addition to offer a potential source of cardiovascular markers, therapeutical potential of EVs reveal exciting opportunities to deliver specific agents by non-immunogenic means to cardiovascular system.

  8. Extracellular Vesicles: Evolving Factors in Stem Cell Biology

    Science.gov (United States)

    Nawaz, Muhammad; Fatima, Farah; Vallabhaneni, Krishna C.; Penfornis, Patrice; Valadi, Hadi; Ekström, Karin; Kholia, Sharad; Whitt, Jason D.; Fernandes, Joseph D.; Pochampally, Radhika; Squire, Jeremy A.; Camussi, Giovanni

    2016-01-01

    Stem cells are proposed to continuously secrete trophic factors that potentially serve as mediators of autocrine and paracrine activities, associated with reprogramming of the tumor microenvironment, tissue regeneration, and repair. Hitherto, significant efforts have been made to understand the level of underlying paracrine activities influenced by stem cell secreted trophic factors, as little is known about these interactions. Recent findings, however, elucidate this role by reporting the effects of stem cell derived extracellular vesicles (EVs) that mimic the phenotypes of the cells from which they originate. Exchange of genetic information utilizing persistent bidirectional communication mediated by stem cell-EVs could regulate stemness, self-renewal, and differentiation in stem cells and their subpopulations. This review therefore discusses stem cell-EVs as evolving communication factors in stem cell biology, focusing on how they regulate cell fates by inducing persistent and prolonged genetic reprogramming of resident cells in a paracrine fashion. In addition, we address the role of stem cell-secreted vesicles in shaping the tumor microenvironment and immunomodulation and in their ability to stimulate endogenous repair processes during tissue damage. Collectively, these functions ensure an enormous potential for future therapies. PMID:26649044

  9. SNAP-25 gene family members differentially support secretory vesicle fusion.

    Science.gov (United States)

    Arora, Swati; Saarloos, Ingrid; Kooistra, Robbelien; van de Bospoort, Rhea; Verhage, Matthijs; Toonen, Ruud F

    2017-06-01

    Neuronal dense-core vesicles (DCVs) transport and secrete neuropeptides necessary for development, plasticity and survival, but little is known about their fusion mechanism. We show that Snap-25 -null mutant (SNAP-25 KO) neurons, previously shown to degenerate after 4 days in vitro (DIV), contain fewer DCVs and have reduced DCV fusion probability in surviving neurons at DIV14. At DIV3, before degeneration, SNAP-25 KO neurons show normal DCV fusion, but one day later fusion is significantly reduced. To test if other SNAP homologs support DCV fusion, we expressed SNAP-23, SNAP-29 or SNAP-47 in SNAP-25 KO neurons. SNAP-23 and SNAP-29 rescued viability and supported DCV fusion in SNAP-25 KO neurons, but SNAP-23 did so more efficiently. SNAP-23 also rescued synaptic vesicle (SV) fusion while SNAP-29 did not. SNAP-47 failed to rescue viability and did not support DCV or SV fusion. These data demonstrate a developmental switch, in hippocampal neurons between DIV3 and DIV4, where DCV fusion becomes SNAP-25 dependent. Furthermore, SNAP-25 homologs support DCV and SV fusion and neuronal viability to variable extents - SNAP-23 most effectively, SNAP-29 less so and SNAP-47 ineffectively. © 2017. Published by The Company of Biologists Ltd.

  10. AP2 hemicomplexes contribute independently to synaptic vesicle endocytosis.

    Science.gov (United States)

    Gu, Mingyu; Liu, Qiang; Watanabe, Shigeki; Sun, Lin; Hollopeter, Gunther; Grant, Barth D; Jorgensen, Erik M

    2013-03-05

    The clathrin adaptor complex AP2 is thought to be an obligate heterotetramer. We identify null mutations in the α subunit of AP2 in the nematode Caenorhabditis elegans. α-adaptin mutants are viable and the remaining μ2/β hemicomplex retains some function. Conversely, in μ2 mutants, the alpha/sigma2 hemicomplex is localized and is partially functional. α-μ2 double mutants disrupt both halves of the complex and are lethal. The lethality can be rescued by expression of AP2 components in the skin, which allowed us to evaluate the requirement for AP2 subunits at synapses. Mutations in either α or μ2 subunits alone reduce the number of synaptic vesicles by about 30%; however, simultaneous loss of both α and μ2 subunits leads to a 70% reduction in synaptic vesicles and the presence of large vacuoles. These data suggest that AP2 may function as two partially independent hemicomplexes. DOI:http://dx.doi.org/10.7554/eLife.00190.001.

  11. Functions of Cancer-Derived Extracellular Vesicles in Immunosuppression.

    Science.gov (United States)

    Czernek, Liliana; Düchler, Markus

    2017-08-01

    Extracellular vesicles, including exosomes, constitute an important element of intercellular communication by carrying a variety of molecules from producer to target cells. The transport of mRNA and miRNA can directly modulate gene expression in the target cells. The miRNA content in exosomes is characteristic for the cell from which the vesicles were derived enabling the usage of exosomes as biomarkers for the diagnosis various diseases, including cancer. Cancer-derived exosomes support the survival and progression of tumors in many ways and also contribute to the neutralization of the anti-cancer immune response. Exosomes participate in all known mechanisms by which cancer evades the immune system. They influence the differentiation and activation of immune suppressor cells, they modulate antigen presentation, and are able to induce T-cell apoptosis. Although cancer-derived exosomes mainly suppress the immune system and facilitate tumor progression, they are also important sources of tumor antigens with potential clinical application in stimulating immune responses. This review summarizes how exosomes assist cancer to escape immune recognition and to acquire control over the immune system.

  12. Association of Extracellular Membrane Vesicles with Cutaneous Wound Healing

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    Uyen Thi Trang Than

    2017-05-01

    Full Text Available Extracellular vesicles (EVs are membrane-enclosed vesicles that are released into the extracellular environment by various cell types, which can be classified as apoptotic bodies, microvesicles and exosomes. EVs have been shown to carry DNA, small RNAs, proteins and membrane lipids which are derived from the parental cells. Recently, several studies have demonstrated that EVs can regulate many biological processes, such as cancer progression, the immune response, cell proliferation, cell migration and blood vessel tube formation. This regulation is achieved through the release and transport of EVs and the transfer of their parental cell-derived molecular cargo to recipient cells. This thereby influences various physiological and sometimes pathological functions within the target cells. While intensive investigation of EVs has focused on pathological processes, the involvement of EVs in normal wound healing is less clear; however, recent preliminarily investigations have produced some initial insights. This review will provide an overview of EVs and discuss the current literature regarding the role of EVs in wound healing, especially, their influence on coagulation, cell proliferation, migration, angiogenesis, collagen production and extracellular matrix remodelling.

  13. Fatty acid vesicles acting as expanding horizon for transdermal delivery.

    Science.gov (United States)

    Kumar, Lalit; Verma, Shivani; Kumar, Sanjeev; Prasad, Deo Nandan; Jain, Amit Kumar

    2017-03-01

    The body is protected against the external environment by the skin due to its physical barrier nature. Stratum corneum composed of corneocytes surrounded by lipid region performs a major barrier function as it lies in the uppermost area of skin. Alteration in barrier function, increase in permeability, and disorganization of stratum corneum represent diseased skin. Drugs applied to the diseased skin should induce a local effect at the site of application or area close to it along with cutaneous absorption rather than percutaneous absorption. Conventional formulations like ointments, gels, and creams suffer from the drawback of limited local activity. For the enhancement of drug penetration and localization of the drug at the site of action approaches explored are liposomes, niosomes, ethosomes microparticles, and solid lipid nanoparticles. Vesicles composed of fatty acids like oleic acid and linoleic acid represent the new approach used for transdermal penetration and localization. In this review article, our major aim was to explore the applications of fatty acid vesicles for transdermal delivery of various bioactives.

  14. Electroformation of Giant Vesicles on a Polymer Mesh

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    Yukihisa Okumura

    2011-07-01

    Full Text Available Electroformation of cell-sized lipid membrane vesicles (giant vesicles, GVs from egg yolk phosphatidylcholine under applied electric voltage was examined on a substrate of a polymer mesh placed between two planar indium tin oxide coated glass electrodes. Under appropriate conditions, GVs were formed in good yield on meshes of various polymer materials, namely, hydrophobic poly(propylene, poly(ethylene terephthalate, a carbon fiber/nylon composite, and relatively hydrophilic nylon. Arranging threads in a mesh structure with appropriate openings improved GV formation compared to simply increasing the number of threads. For optimal electroformation of GVs, the size and shape of a mesh opening were crucial. With a too large opening, GV formation deteriorated. When the sides of an opening were partially missing, GV formation did not occur efficiently. With an adequate opening, a deposited lipid solution could fill the opening, and a relatively uniform lipid deposit formed on the surface of threads after evaporation of the solvent. This could supply a sufficient amount of lipids to the opening and also prevent a lipid deposit from becoming too thick for electroformation. As a result, good GV formation was often observed in openings filled with swelled lipid.

  15. Effect of Counter Electrode in Electroformation of Giant Vesicles

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    Shuuhei Oana

    2011-11-01

    Full Text Available Electroformation of cell-sized lipid membrane vesicles (giant vesicles, GVs, from egg yolk phosphatidylcholine, was examined varying the shape of the counter electrode. Instead of a planar ITO (indium tin oxide electrode commonly used, platinum wire mesh was employed as a counter electrode facing lipid deposit on a planar formation electrode. The modification did not significantly alter GV formation, and many GVs of 30–50 µm, some as large as 100 µm, formed as with the standard setup, indicating that a counter electrode does not have to be a complete plane. When the counter electrode was reduced to a set of two parallel platinum wires, GV formation deteriorated. Some GVs formed, but only in close proximity to the counter electrode. Lower electric voltage with this setup no longer yielded GVs. Instead, a large onion-like multilamellar structure was observed. The deteriorated GV formation and the formation of a multilamellar structure seemed to indicate the weakened effect of the electric field on lipid deposit due to insufficient coverage with a small counter electrode. Irregular membranous objects formed by spontaneous swelling of lipid without electric voltage gradually turned into multilamellar structure upon following application of voltage. No particular enhancement of GV formation was observed when lipid deposit on a wire formation electrode was used in combination with a large planar counter electrode.

  16. Facile preparation of salivary extracellular vesicles for cancer proteomics

    Science.gov (United States)

    Sun, Yan; Xia, Zhijun; Shang, Zhi; Sun, Kaibo; Niu, Xiaomin; Qian, Liqiang; Fan, Liu-Yin; Cao, Cheng-Xi; Xiao, Hua

    2016-04-01

    Extracellular vesicles (EVs) are membrane surrounded structures released by cells, which have been increasingly recognized as mediators of intercellular communication. Recent reports indicate that EVs participate in important biological processes and could serve as potential source for cancer biomarkers. As an attractive EVs source with merit of non-invasiveness, human saliva is a unique medium for clinical diagnostics. Thus, we proposed a facile approach to prepare salivary extracellular vesicles (SEVs). Affinity chromatography column combined with filter system (ACCF) was developed to efficiently remove the high abundant proteins and viscous interferences of saliva. Protein profiling in the SEVs obtained by this strategy was compared with conventional centrifugation method, which demonstrated that about 70% more SEVs proteins could be revealed. To explore its utility for cancer proteomics, we analyzed the proteome of SEVs in lung cancer patients and normal controls. Shotgun proteomic analysis illustrated that 113 and 95 proteins have been identified in cancer group and control group, respectively. Among those 63 proteins that have been consistently discovered only in cancer group, 12 proteins are lung cancer related. Our results demonstrated that SEVs prepared through the developed strategy are valuable samples for proteomics and could serve as a promising liquid biopsy for cancer.

  17. Extracellular Vesicles from Ovarian Carcinoma Cells Display Specific Glycosignatures

    Directory of Open Access Journals (Sweden)

    Joana Gomes

    2015-08-01

    Full Text Available Cells release vesicles to the extracellular environment with characteristic nucleic acid, protein, lipid, and glycan composition. Here we have isolated and characterized extracellular vesicles (EVs and total cell membranes (MBs from ovarian carcinoma OVMz cells. EVs were enriched in specific markers, including Tsg101, CD63, CD9, annexin-I, and MBs contained markers of cellular membrane compartments, including calnexin, GRASP65, GS28, LAMP-1, and L1CAM. The glycoprotein galectin-3 binding protein (LGALS3BP was strongly enriched in EVs and it contained sialylated complex N-glycans. Lectin blotting with a panel of lectins showed that EVs had specific glycosignatures relative to MBs. Furthermore, the presence of glycoproteins bearing complex N-glycans with α2,3-linked sialic acid, fucose, bisecting-GlcNAc and LacdiNAc structures, and O-glycans with the T-antigen were detected. The inhibition of N-glycosylation processing from high mannose to complex glycans using kifunensine caused changes in the composition of EVs and induced a decrease of several glycoproteins. In conclusion, the results showed that glycosignatures of EVs were specific and altered glycosylation within the cell affected the composition and/or dynamics of EVs release. Furthermore, the identified glycosignatures of EVs could provide novel biomarkers for ovarian cancer.

  18. Vesiclepedia: A Compendium for Extracellular Vesicles with Continuous Community Annotation

    Science.gov (United States)

    Kalra, Hina; Simpson, Richard J.; Ji, Hong; Aikawa, Elena; Altevogt, Peter; Askenase, Philip; Bond, Vincent C.; Borràs, Francesc E.; Breakefield, Xandra; Budnik, Vivian; Buzas, Edit; Camussi, Giovanni; Clayton, Aled; Cocucci, Emanuele; Falcon-Perez, Juan M.; Gabrielsson, Susanne; Gho, Yong Song; Gupta, Dwijendra; Harsha, H. C.; Hendrix, An; Hill, Andrew F.; Inal, Jameel M.; Jenster, Guido; Krämer-Albers, Eva-Maria; Lim, Sai Kiang; Llorente, Alicia; Lötvall, Jan; Marcilla, Antonio; Mincheva-Nilsson, Lucia; Nazarenko, Irina; Nieuwland, Rienk; Nolte-'t Hoen, Esther N. M.; Pandey, Akhilesh; Patel, Tushar; Piper, Melissa G.; Pluchino, Stefano; Prasad, T. S. Keshava; Rajendran, Lawrence; Raposo, Graca; Record, Michel; Reid, Gavin E.; Sánchez-Madrid, Francisco; Schiffelers, Raymond M.; Siljander, Pia; Stensballe, Allan; Stoorvogel, Willem; Taylor, Douglas; Thery, Clotilde; Valadi, Hadi; van Balkom, Bas W. M.; Vázquez, Jesús; Vidal, Michel; Wauben, Marca H. M.; Yáñez-Mó, María; Zoeller, Margot; Mathivanan, Suresh

    2012-01-01

    Extracellular vesicles (EVs) are membraneous vesicles released by a variety of cells into their microenvironment. Recent studies have elucidated the role of EVs in intercellular communication, pathogenesis, drug, vaccine and gene-vector delivery, and as possible reservoirs of biomarkers. These findings have generated immense interest, along with an exponential increase in molecular data pertaining to EVs. Here, we describe Vesiclepedia, a manually curated compendium of molecular data (lipid, RNA, and protein) identified in different classes of EVs from more than 300 independent studies published over the past several years. Even though databases are indispensable resources for the scientific community, recent studies have shown that more than 50% of the databases are not regularly updated. In addition, more than 20% of the database links are inactive. To prevent such database and link decay, we have initiated a continuous community annotation project with the active involvement of EV researchers. The EV research community can set a gold standard in data sharing with Vesiclepedia, which could evolve as a primary resource for the field. PMID:23271954

  19. Vesiclepedia: a compendium for extracellular vesicles with continuous community annotation.

    Directory of Open Access Journals (Sweden)

    Hina Kalra

    Full Text Available Extracellular vesicles (EVs are membraneous vesicles released by a variety of cells into their microenvironment. Recent studies have elucidated the role of EVs in intercellular communication, pathogenesis, drug, vaccine and gene-vector delivery, and as possible reservoirs of biomarkers. These findings have generated immense interest, along with an exponential increase in molecular data pertaining to EVs. Here, we describe Vesiclepedia, a manually curated compendium of molecular data (lipid, RNA, and protein identified in different classes of EVs from more than 300 independent studies published over the past several years. Even though databases are indispensable resources for the scientific community, recent studies have shown that more than 50% of the databases are not regularly updated. In addition, more than 20% of the database links are inactive. To prevent such database and link decay, we have initiated a continuous community annotation project with the active involvement of EV researchers. The EV research community can set a gold standard in data sharing with Vesiclepedia, which could evolve as a primary resource for the field.

  20. Rab proteins: The key regulators of intracellular vesicle transport

    Energy Technology Data Exchange (ETDEWEB)

    Bhuin, Tanmay [Cell and Developmental Biology Unit, Department of Zoology, The University of Burdwan, Golapbag 713104 (India); Roy, Jagat Kumar, E-mail: jkroy@bhu.ac.in [Cytogenetics Laboratory, Department of Zoology, Banaras Hindu University, Varanasi 221005 (India)

    2014-10-15

    Vesicular/membrane trafficking essentially regulates the compartmentalization and abundance of proteins within the cells and contributes in many signalling pathways. This membrane transport in eukaryotic cells is a complex process regulated by a large and diverse array of proteins. A large group of monomeric small GTPases; the Rabs are essential components of this membrane trafficking route. Most of the Rabs are ubiquitously expressed proteins and have been implicated in vesicle formation, vesicle motility/delivery along cytoskeleton elements and docking/fusion at target membranes through the recruitment of effectors. Functional impairments of Rabs affecting transport pathways manifest different diseases. Rab functions are accompanied by cyclical activation and inactivation of GTP-bound and GDP-bound forms between the cytosol and membranes which is regulated by upstream regulators. Rab proteins are characterized by their distinct sub-cellular localization and regulate a wide variety of endocytic, transcytic and exocytic transport pathways. Mutations of Rabs affect cell growth, motility and other biological processes. - Highlights: • Rab proteins regulate different signalling pathways. • Deregulation of Rabs is the fundamental causes of a variety of human diseases. • This paper gives potential directions in developing therapeutic targets. • This paper also gives ample directions for modulating pathways central to normal physiology. • These are the huge challenges for drug discovery and delivery in near future.