Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Liposomes remain intact when complexed with polycationic brushes.

ABSTRACT: Anionic liposomes adsorb onto the surface of spherical polymer particles bearing grafted linear cationic macromolecules. The size, shape, and encapsulation ability of the liposomes remain unchanged upon adsorption, thus providing immobilized self-organizing containers that have potential applications in the biomedical field.

SUBMITTER: Yaroslavov AA

PROVIDER: S-EPMC2865170 | biostudies-literature | 2010 May

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Liposomes remain intact when complexed with polycationic brushes.

Yaroslavov Alexander A AA Sybachin Andrei V AV Schrinner Marc M Ballauff Matthias M Tsarkova Larisa L Kesselman Ellina E Schmidt Judith J Talmon Yeshayahu Y Menger Fredric M FM

Journal of the American Chemical Society 20100501 17

Anionic liposomes adsorb onto the surface of spherical polymer particles bearing grafted linear cationic macromolecules. The size, shape, and encapsulation ability of the liposomes remain unchanged upon adsorption, thus providing immobilized self-organizing containers that have potential applications in the biomedical field. ...[more]

PMID: 20387892

Similar Datasets

Activated chemoreceptor arrays remain intact and hexagonally packed.

Project description:Bacterial chemoreceptors cluster into exquisitively sensitive, tunable, highly ordered, polar arrays. While these arrays serve as paradigms of cell signalling in general, it remains unclear what conformational changes transduce signals from the periplasmic tips, where attractants and repellents bind, to the cytoplasmic signalling domains. Conflicting reports support and contest the hypothesis that activation causes large changes in the packing arrangement of the arrays, up to and including their complete disassembly. Using electron cryotomography, here we show that in Caulobacter crescentus, chemoreceptor arrays in cells grown in different media and immediately after exposure to the attractant galactose all exhibit the same 12 nm hexagonal packing arrangement, array size and other structural parameters. ?cheB and ?cheR mutants mimicking attractant- or repellent-bound states prior to adaptation also show the same lattice structure. We conclude that signal transduction and amplification must be accomplished through only small, nanoscale conformational changes.

| S-EPMC3641884 | biostudies-literature

Cortical diurnal rhythms remain intact with microglial depletion.

Project description:Microglia are subject to change in tandem with the endogenously generated biological oscillations known as our circadian rhythm. Studies have shown microglia harbor an intrinsic molecular clock which regulates diurnal changes in morphology and influences inflammatory responses. In the adult brain, microglia play an important role in the regulation of condensed extracellular matrix structures called perineuronal nets (PNNs), and it has been suggested that PNNs are also regulated in a circadian and diurnal manner. We sought to determine whether microglia mediate the diurnal regulation of PNNs via CSF1R inhibitor dependent microglial depletion in C57BL/6J mice, and how the absence of microglia might affect cortical diurnal gene expression rhythms. While we observe diurnal differences in microglial morphology, where microglia are most ramified at the onset of the dark phase, we do not find diurnal differences in PNN intensity. However, PNN intensity increases across many brain regions in the absence of microglia, supporting a role for microglia in the regulation of PNNs. Here, we also show that cortical diurnal gene expression rhythms are intact, with no cycling gene changes without microglia. These findings demonstrate a role for microglia in the maintenance of PNNs, but not in the maintenance of diurnal rhythms.

| S-EPMC8742049 | biostudies-literature

Cortical diurnal rhythms remain intact with microglial depletion

Project description:This dataset allows for the exploration of cortical genes at across different timepoints (ZT2, ZT6, ZT10, ZT14, ZT 18, ZT22) in control C57BL/6J mice compared to microglia-depleted C57BL/6J mice (10 day PLX5622 treatment).

2021-11-18 | GSE188989 | GEO

Disulfide bridges remain intact while native insulin converts into amyloid fibrils.

Project description:Amyloid fibrils are ?-sheet-rich protein aggregates commonly found in the organs and tissues of patients with various amyloid-associated diseases. Understanding the structural organization of amyloid fibrils can be beneficial for the search of drugs to successfully treat diseases associated with protein misfolding. The structure of insulin fibrils was characterized by deep ultraviolet resonance Raman (DUVRR) and Nuclear Magnetic Resonance (NMR) spectroscopy combined with hydrogen-deuterium exchange. The compositions of the fibril core and unordered parts were determined at single amino acid residue resolution. All three disulfide bonds of native insulin remained intact during the aggregation process, withstanding scrambling. Three out of four tyrosine residues were packed into the fibril core, and another aromatic amino acid, phenylalanine, was located in the unordered parts of insulin fibrils. In addition, using all-atom MD simulations, the disulfide bonds were confirmed to remain intact in the insulin dimer, which mimics the fibrillar form of insulin.

| S-EPMC3365881 | biostudies-literature

Cortical diurnal rhythms remain intact with microglial depletion

Project description:Cortical diurnal rhythms remain intact with microglial depletion

| PRJNA780947 | ENA

Liposomes with Low Levels of Grafted Poly(ethylene glycol) Remain Susceptible to Destabilization by Anti-Poly(ethylene glycol) Antibodies.

Project description:Binding of anti-PEG antibodies to poly(ethylene glycol) (PEG) on the surface of PEGylated liposomal doxorubicin (PLD) in vitro and in rats can activate complement and cause the rapid release of doxorubicin from the liposome interior. Here, we find that irinotecan liposomes (IL) and L-PLD, which have 16-fold lower levels of 1,2-distearoyl-sn-glycero-3-phosphoethanolamine (DSPE)-PEG2000 in their liposome membrane as compared to PLD, generate less complement activation but remain sensitive to destabilization and drug release by anti-PEG antibodies. Complement activation and liposome destabilization correlated with the theoretically estimated number of antibody molecules bound per liposome. Drug release from liposomes proceeded through the alternative complement pathway but was accelerated by the classical complement pathway. In contrast to PLD destabilization by anti-PEG immunoglobulin G (IgG), which proceeded by the insertion of membrane attack complexes in the lipid bilayer of otherwise intact PLD, anti-PEG IgG promoted the fusion of L-PLD, and IL to form unilamellar and oligo-vesicular liposomes. Anti-PEG immunoglobulin M (IgM) induced drug release from all liposomes (PLD, L-PLD, and IL) via the formation of unilamellar and oligo-vesicular liposomes. Anti-PEG IgG destabilized both PLD and L-PLD in rats, indicating that the reduction of PEG levels on liposomes is not an effective approach to prevent liposome destabilization by anti-PEG antibodies.

| S-EPMC11342370 | biostudies-literature

Superresolution and Fluorescence Dynamics Evidence Reveal That Intact Liposomes Do Not Cross the Human Skin Barrier.

Project description:In this study we use the combination of super resolution optical microscopy and raster image correlation spectroscopy (RICS) to study the mechanism of action of liposomes as transdermal drug delivery systems in human skin. Two different compositions of liposomes were applied to newly excised human skin, a POPC liposome and a more flexible liposome containing the surfactant sodium cholate. Stimulated emission depletion microscopy (STED) images of intact skin and cryo-sections of skin treated with labeled liposomes were recorded displaying an optical resolution low enough to resolve the 100 nm liposomes in the skin. The images revealed that virtually none of the liposomes remained intact beneath the skin surface. RICS two color cross correlation diffusion measurements of double labeled liposomes confirmed these observations. Our results suggest that the liposomes do not act as carriers that transport their cargo directly through the skin barrier, but mainly burst and fuse with the outer lipid layers of the stratum corneum. It was also found that the flexible liposomes showed a greater delivery of the fluorophore into the stratum corneum, indicating that they functioned as chemical permeability enhancers.

| S-EPMC4709185 | biostudies-literature

Sustained zero-order release of intact ultra-stable drug-loaded liposomes from an implantable nanochannel delivery system.

Project description:Metronomic chemotherapy supports the idea that long-term, sustained, constant administration of chemotherapeutics, currently not achievable, could be effective against numerous cancers. Particularly appealing are liposomal formulations, used to solubilize hydrophobic therapeutics and minimize side effects, while extending drug circulation time and enabling passive targeting. As liposome alone cannot survive in circulation beyond 48 h, sustaining their constant plasma level for many days is a challenge. To address this, we develop, as a proof of concept, an implantable nanochannel delivery system and ultra-stable PEGylated lapatinib-loaded liposomes, and we demonstrate the release of intact vesicles for over 18 d. Further, we investigate intravasation kinetics of subcutaneously delivered liposomes and verify their biological activity post nanochannel release on BT474 breast cancer cells. The key innovation of this work is the combination of two nanotechnologies to exploit the synergistic effect of liposomes, demonstrated as passive-targeting vectors and nanofluidics to maintain therapeutic constant plasma levels. In principle, this approach could maximize efficacy of metronomic treatments.

| S-EPMC3970317 | biostudies-literature

Absorbable cyst brushes.

Project description:Cytobrushes are used for low-invasive sample collection and screening in multiple diseases, with a significant impact on early detection, prevention, and diagnosis. This study focuses on improving the safety of cell brushing in hard-to-reach locations by exploring brush construction from absorbable materials. We investigated the efficacy of loop brushes made of absorbable suture wires of Chirlac, Chirasorb, Monocryl, PDS II, Vicryl Rapid, Glycolon, and Catgut during their operation in conjunction with fine-needle aspiration in an artificial cyst model. PDS II brushes demonstrated the highest efficiency, while Monocryl and Catgut also provided a significant brushing effect. Efficient brushes portrayed higher flexural rigidity than their counterparts, and their efficiency was inversely proportional to their plastic deformation by the needle. Our results open avenues for safer cell biopsies in hard-to-reach locations by utilizing brushes composed of absorbable materials.

| S-EPMC10447279 | biostudies-literature

RNAseq of liver dendritic cells targeted with empty liposomes or curcumin liposomes

Project description:Non-alcoholic fatty liver disease (NAFLD) is a common complication of obesity, where insulin resistance and hepatocyte fat deposition may progress to steatohepatitis (NASH) and fibrosis/ cirrhosis. NASH has no approved treatment. Consequent upon hepatic fat deposition, NF-κB activation in hepatic myeloid cells mediates inflammation and NASH progression. We delivered micro-doses of liposome-encapsulated lipophilic NF-κB inhibitors, curcumin or 1,25-dihydroxy-vitamin D3 (calcitriol), to the pro-fibrogenic inflammatory liver macrophages and dendritic cells (DCs) in diet-induced NASH. After i.v. administration, liver was the primary organ targeted. MHC class-II+ hepatic DCs taking up liposomes in mice and human were F4/80+ and CD14+ respectively, were lipid-laden and expressed pro-inflammatory genes. Curcumin or calcitriol liposomes suppressed hepatic inflammation, fibrosis and fat accumulation, and reduced insulin resistance associated with suppression of immune activation, cell cycle and collagen deposition pathways in vivo. Thus, hepatic inflammatory DCs passively targeted with liposomes encapsulating lipophilic NF-κB inhibitors are beneficial in NASH.

2020-01-22 | GSE94592 | GEO

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data