Kooperativer Bibliotheksverbund

Berlin Brandenburg

and
and

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Wagner, Sylvia  (36)
Type of Medium
Language
Year
  • 1
    Language: English
    In: Chromatographia, 2010, Vol.72(7), pp.659-664
    Description: Phospholipids are major constituents of biological membranes in plants and animals. Phospholipid-containing substances, such as lecithin, have also received increasing attention as emulsifiers in pharmaceutical drug delivery systems. The phospholipids phosphatidylcholine, phosphatidylethanolamine, phosphatidylinositol, their lysophosphatidyl hydrolysis products and sphingomyelin, were quantified in lecithin and lecithin-containing drug-delivery emulsions. Lysophospholipids are constituents of lecithin, but their formation during thermal sterilization of the investigated drug delivery systems might contribute to the concentrations found in the emulsions. ; Includes references ; p. 659-664.
    Keywords: Phospholipids ; Lysophospholipids, Lecithin, Phosphatidylserine, Phosphatidylethanolamine And Phosphatidylcholine ; Electospray Mass Spectrometry ; Column Liquid Chromatography
    ISSN: 0009-5893
    E-ISSN: 16121112
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Language: English
    In: Pharmaceutical Research, 2015, Vol.32(12), pp.3986-3998
    Description: Byline: Susanne Beyer (1), Aline Moosmann (2), Astrid S. Kahnt (3), Thomas Ulshofer (4), Michael J. Parnham (4), Nerea Ferreiros (5), Sylvia Wagner (2), Matthias G. Wacker (1) Keywords: biorelevant release; Eudragit[R] RS 100; nanoparticles; peroral drug delivery; Ussing chamber Abstract: Purpose The contribution of permeability and drug release to drug targeting were investigated in the course of development of a nanosized formulation of the anti-inflammatory compound TMP-001, for the local treatment in the gastrointestinal tract. Methods TMP-001 was encapsulated by nanoprecipitation into Eudragit[R] RS 100. The permeability of these carriers was investigated in an Ussing chamber model and the release rate was determined under biorelevant conditions. Formulation toxicity and particle-cell-interaction were investigated by flow cytometry, fluorescence and electron microscopy. Furthermore, spray drying was performed. Results Effective internalization of Eudragit[R]-nanoparticles into cancer cells was demonstrated. A burst release of the nanoparticles implied poor interaction of TMP-001 with Eudragit[R]. A sustained release (70.5% release after 30 min compared to 98.0% for the API) was accomplished after spray drying yielded an increased particle size. Recovery rate of TMP-001 after spray drying was 94.2[+ or -]5.9%. Conclusion The release of API from polymeric nanoparticles contributes profoundly to the in vivo-performance of drug delivery devices in the gastrointestinal tract. The impact of drug-polymer interaction and particle size was analyzed. Sustained release of TMP-001 could only be achieved by increasing particle size. Therefore, biorelevant release testing has been demonstrated to be a valid tool for nanoformulation design. Author Affiliation: (1) Institute of Pharmaceutical Technology, Goethe University, Max-von-Laue-Str. 9, 60438, Frankfurt (Main), Germany (2) Department of Bioprocess Technologies & Nanotechnology, Fraunhofer Institute for Biomedical Engineering, Ensheimer Stra[sz]e 48, 66386, St. Ingbert, Germany (3) Institute of Pharmaceutical Chemistry, Goethe University Frankfurt, Max-von-Laue-Str. 9, 60438, Frankfurt (Main), Germany (4) Fraunhofer Institute of Molecular Biology and Applied Ecology, Project Group for Translational Medicine and Pharmacology, Theodor-Stern-Kai 7, 60596, Frankfurt (Main), Germany (5) Institute of Clinical Pharmacology, Goethe University Hospital, Theodor-Stern-Kai 7, 60596, Frankfurt am Main, Germany Article History: Registration Date: 15/07/2015 Received Date: 30/04/2015 Accepted Date: 15/07/2015 Online Date: 28/07/2015
    Keywords: biorelevant release ; Eudragit® RS 100 ; nanoparticles ; peroral drug delivery ; Ussing chamber
    ISSN: 0724-8741
    E-ISSN: 1573-904X
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    Language: English
    In: Nanotechnology, 2011, Vol.22(24), p.245102 (12pp)
    Description: The second generation photosensitizer m THPC was approved by the European Medicines Agency (EMA) for the palliative treatment of advanced head and neck cancer in October 2001. It is known that m THPC possesses a significant phototoxicity against a variety of human cancer cells in vitro but also exhibits dark toxicity and can cause adverse effects (especially skin photosensitization). Due to its poor water solubility, the administration of hydrophobic photosensitizer still presents several difficulties. To overcome the administration problems, the use of nanoparticles as drug carrier systems is much investigated. Nanoparticles based on poly(lactic-co-glycolic acid) (PLGA) have been extensively studied as delivery systems into tumours due to their biocompatibility and biodegradability. The goal of this study was the comparison of free m THPC and m THPC-loaded PLGA nanoparticles concerning cytotoxicity and intracellular accumulation in human colon carcinoma cells (HT29). The nanoparticles delivered the photosensitizer to the colon carcinoma cells and enabled drug release without losing its activity. The cytotoxicity assays showed a time- and concentration-dependent decrease in cell proliferation and viability after illumination. However, first and foremost m THPC lost its dark toxic effects using the PLGA nanoparticles as a drug carrier system. Therefore, PLGA nanoparticles are a promising drug carrier system for the hydrophobic photosensitizer m THPC.
    Keywords: Colonic Neoplasms -- Metabolism ; Intracellular Space -- Metabolism ; Lactic Acid -- Toxicity ; Mesoporphyrins -- Toxicity ; Nanoparticles -- Toxicity ; Polyglycolic Acid -- Toxicity;
    ISSN: 0957-4484
    E-ISSN: 1361-6528
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    Language: English
    In: PLoS ONE, 2012, Vol.7(3), p.e32568
    Description: The blood-brain barrier (BBB) represents an insurmountable obstacle for most drugs thus obstructing an effective treatment of many brain diseases. One solution for overcoming this barrier is a transport by binding of these drugs to surface-modified nanoparticles. Especially apolipoprotein E (ApoE) appears to play a major role in the nanoparticle-mediated drug transport across the BBB. However, at present the underlying mechanism is incompletely understood. ; In this study, the uptake of the ApoE-modified nanoparticles into the brain capillary endothelial cells was investigated to differentiate between active and passive uptake mechanism by flow cytometry and confocal laser scanning microscopy. Furthermore, different co-incubation experiments were performed with competing ligands of the respective receptor. ; This study confirms an active endocytotic uptake mechanism and shows the involvement of low density lipoprotein receptor family members, notably the low density lipoprotein receptor related protein, on the uptake of the ApoE-modified nanoparticles into the brain capillary endothelial cells. This knowledge of the uptake mechanism of ApoE-modified nanoparticles enables future developments to rationally create very specific and effective carriers to overcome the blood-brain barrier.
    Keywords: Research Article ; Biology ; Materials Science ; Medicine ; Biotechnology ; Pharmacology ; Biochemistry
    E-ISSN: 1932-6203
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 6
    Language: English
    In: PLoS ONE, 2010, Vol.5(12), p.e14213
    Description: Due to the use of organophosphates (OP) as pesticides and the availability of OP-type nerve agents, an effective medical treatment for OP poisonings is still a challenging problem. The acute toxicity of an OP poisoning is mainly due to the inhibition of acetylcholinesterase (AChE) in the peripheral and central nervous systems (CNS). This results in an increase in the synaptic concentration of the neurotransmitter acetylcholine, overstimulation of cholinergic receptors and disorder of numerous body functions up to death. The standard treatment of OP poisoning includes a combination of a muscarinic antagonist and an AChE reactivator (oxime). However, these oximes can not cross the blood-brain barrier (BBB) sufficiently. Therefore, new strategies are needed to transport oximes over the BBB. ; In this study, we combined different oximes (obidoxime dichloride and two different HI 6 salts, HI 6 dichloride monohydrate and HI 6 dimethanesulfonate) with human serum albumin nanoparticles and could show an oxime transport over an BBB model. In general, the nanoparticulate transported oximes achieved a better reactivation of OP-inhibited AChE than free oximes. ; With these nanoparticles, for the first time, a tool exists that could enable a transport of oximes over the BBB. This is very important for survival after severe OP intoxication. Therefore, these nanoparticulate formulations are promising formulations for the treatment of the peripheral and the CNS after OP poisoning.
    Keywords: Research Article ; Biotechnology ; Neurological Disorders ; Pharmacology -- Drug Development
    E-ISSN: 1932-6203
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 7
    Language: English
    In: PLoS ONE, 01 January 2014, Vol.9(3), p.e92068
    Description: This study was performed to explore the feasibility of tracing nanoparticles for drug transport in the healthy rat brain with a clinical MRI scanner. Phantom studies were performed to assess the R1 ( =  1/T1) relaxivity of different magnetically labeled nanoparticle (MLNP) formulations that were based on biodegradable human serum albumin and that were labeled with magnetite of different size. In vivo MRI measurements in 26 rats were done at 3T to study the effect and dynamics of MLNP uptake in the rat brain and body. In the brain, MLNPs induced T1 changes were quantitatively assessed by T1 relaxation time mapping in vivo and compared to post-mortem results from fluorescence imaging. Following intravenous injection of MLNPs, a visible MLNP uptake was seen in the liver and spleen while no visual effect was seen in the brain. However a histogram analysis of T1 changes in the brain demonstrated global and diffuse presence of MLNPs. The magnitude of these T1 changes scaled with post-mortem fluorescence intensity. This study demonstrates the feasibility of tracking even small amounts of magnetite labeled NPs with a sensitive histogram technique in the brain of a living rodent.
    Keywords: Sciences (General)
    E-ISSN: 1932-6203
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 8
    Language: English
    In: Chromatographia, 2010, Vol.72(7), pp.659-664
    Description: Phospholipids are major constituents of biological membranes in plants and animals. Phospholipid-containing substances, such as lecithin, have also received increasing attention as emulsifiers in pharmaceutical drug delivery systems. The phospholipids phosphatidylcholine, phosphatidylethanolamine, phosphatidylinositol, their lysophosphatidyl hydrolysis products and sphingomyelin, were quantified in lecithin and lecithin-containing drug-delivery emulsions. Lysophospholipids are constituents of lecithin, but their formation during thermal sterilization of the investigated drug delivery systems might contribute to the concentrations found in the emulsions.
    Keywords: Column liquid chromatography ; Electospray mass spectrometry ; Phospholipids ; Lysophospholipids, lecithin, phosphatidylserine, phosphatidylethanolamine and phosphatidylcholine
    ISSN: 0009-5893
    E-ISSN: 1612-1112
    Source: Springer Science & Business Media B.V.
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 9
    Language: English
    In: Toxicology in Vitro, December 2011, Vol.25(8), pp.1557-1567
    Description: ► We compared the cytotoxicity of TP and TP-PM on Jurkat and HT29 cells. ► TP and TP-PM could induce an inhibition of cell growth and proliferation in both tumor cell lines. ► TP and TP-PM induced apoptosis and caused activation of caspase 3/7. ► TP-PM induced in tested cell lines stronger effects than TP. Triptolide (TP), a diterpenoid triepoxide purified from the Chinese herb Hook F is characterized by strong anti-tumor effects on various cancer cells. Except its anti-tumor effects, TP also shows multiple pharmacological side activities, such as anti-inflammatory, immune-suppressive and male anti-fertility. In order to reduce these side effects, especially the immuno-suppressive activity when used to cure cancer, a novel polymeric micelle system containing TP (TP-PM) was constructed. The immune-modulation effects of TP-PM have been evaluated by previous studies. In this study, we compared the cytotoxicity of TP and TP-PM on Jurkat and HT29 cells. Therefore, we determined the cell viability, membrane integrity, cell proliferation, apoptosis, and caspase 3/7 activity after exposure to TP and TP-PM. The results demonstrated that actually low concentrated TP and TP-PM could induce an inhibition of cell growth and proliferation as well as membrane damage in both tumor cell lines. TP and TP-PM induced apoptosis and caused activation of caspase 3/7 even at low concentrations. Both formulations destroyed the membrane of Jurkat cells, nevertheless, TP-PM showed stronger pernicious effects. In general, TP-PM induced in both tested cell lines stronger effects than TP. Therefore, polymeric micelles can be considered as promising carriers for TP in cancer therapy.
    Keywords: Cytotoxicity ; Triptolide ; Polymeric Micelles ; In Vitro ; Pharmacy, Therapeutics, & Pharmacology ; Chemistry ; Public Health
    ISSN: 0887-2333
    E-ISSN: 1879-3177
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 10
    Language: English
    In: PLoS ONE, 01 January 2016, Vol.11(1), p.e0146378
    Description: Delayed graft function is a prevalent clinical problem in renal transplantation for which there is no objective system to predict occurrence in advance. It can result in a significant increase in the necessity for hospitalisation post-transplant and is a significant risk factor for other post-transplant complications.The importance of microRNAs (miRNAs), a specific subclass of small RNA, have been clearly demonstrated to influence many pathways in health and disease. To investigate the influence of miRNAs on renal allograft performance post-transplant, the expression of a panel of miRNAs in pre-transplant renal biopsies was measured using qPCR. Expression was then related to clinical parameters and outcomes in two independent renal transplant cohorts.Here we demonstrate, in two independent cohorts of pre-implantation human renal allograft biopsies, that a novel pre-transplant renal performance scoring system (GRPSS), can determine the occurrence of DGF with a high sensitivity (〉90%) and specificity (〉60%) for donor allografts pre-transplant, using just three senescence associated microRNAs combined with donor age and type of organ donation.These results demonstrate a relationship between pre-transplant microRNA expression levels, cellular biological ageing pathways and clinical outcomes for renal transplantation. They provide for a simple, rapid quantitative molecular pre-transplant assay to determine post-transplant allograft function and scope for future intervention. Furthermore, these results demonstrate the involvement of senescence pathways in ischaemic injury during the organ transplantation process and an indication of accelerated bio-ageing as a consequence of both warm and cold ischaemia.
    Keywords: Sciences (General)
    E-ISSN: 1932-6203
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. Further information can be found on the KOBV privacy pages