Library

feed icon rss

Your email was sent successfully. Check your inbox.

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

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature America, Inc.
    Nature biotechnology 17 (1999), S. 26-26 
    ISSN: 1546-1696
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: [Auszug] Alain Rolland is Vice President, Research & Development and Head of The Woodlands Center at Valentis, Inc., a publicly traded biologics delivery company formed in March 1999 through the merger of GeneMedicine and Megabios. At Valentis, he leads the company's plasmid therapeutics ...
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 1546-1696
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: [Auszug] A cationic lipid-based delivery system composed of N [(1-(2,3-dioleyloxy)propyl)]-N,N,N-trimethylammonium chloride (DOTMA) and cholesterol, at a 4:1 mole ratio, was developed to express anti-angiogenic gene products from normal and tumor vasculature upon intravenous administration. Plasmid ...
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    ISSN: 1546-1696
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: [Auszug] Tumors require ongoing angiogenesis to support their growth. Inhibition of angiogenesis by production of angiostatic factors should be a viable approach for cancer gene therapy. Endostatin, a potent angiostatic factor, was expressed in mouse muscle and secreted into the bloodstream for up to 2 ...
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    ISSN: 1573-904X
    Keywords: site-specific drug delivery ; transfollicular route ; adapalene ; in vitro cutaneous penetration ; follicular targeting ; poly(lactide-co-glycolide) microspheres ; rhino mouse model ; in vivo cutaneous distribution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract In order to improve the therapeutic index of adapalene, a new drug under development for the treatment of acne, site-specific delivery to the hair follicles using 50:50 poly(DL-lactic-co-glycolic acid) microspheres as particulate carriers was investigated in vitro and in vivo. The percutaneous penetration pathway of the microspheres was shown to be dependent on their mean diameter. Thus, after topical application onto hairless rat or human skin, adapalene-loaded microspheres (5-µm diameter) were specifically targeted to the follicular ducts and did not penetrate via the stratum corneum. The in vitro release of adapalene from the microspheres into artificial sebum at 37°C was controlled and faster than the in vivo sebum excretion in humans. Aiming to reduce either the applied dose of drug or the frequency of administration, different formulations of adapalene-loaded microspheres were evaluated in vivo in the rhino mouse model. A dose-related comedolytic activity of topical formulations of adapalene-loaded microspheres was observed in this model. Furthermore, by applying a site-specific drug delivery system (0.1% adapalene) every other day or by administering a 10-fold less concentrated targeted formulation (0.01%) every day, a pharmacological activity equivalent to a daily application of an aqueous gel containing drug crystals (0.1% adapalene) was observed. Since an aqueous gel containing 10% adapalene-loaded microspheres was not irritating in a rabbit skin irritancy test, this formulation was applied onto forearms of human volunteers. Site-specific drug delivery was further evidenced by follicular biopsy. These results support the view that follicular drug targeting using 5-µm polymeric microspheres may represent a promising therapeutic approach for the treatment of pathologies associated with pilosebaceous units.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Pharmaceutical research 12 (1995), S. 1435-1438 
    ISSN: 1573-904X
    Keywords: surface tension ; micelles ; block copolymers ; phagocytosis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Purpose. This work was carried out to determine the surface tension of block copolymer micelles of 14C labelled ABA poly (oxyethylene-bi-isoprene-b-oxyethylene) which have a long circulating half life in animals. Methods. The method used was that of phagocytosis. The percentage of micelles phagocytosed by human mononuclear cells was determined in solutions of different surface tension. Results. The values obtained were 72 mN/m which may be predicted for a particle with a long circulating half life in animals. The method also gave an estimate of the surface tension for the mononuclear cells. Conclusions. This technique has the advantage of determining the surface tension of highly hydrated small particles including stable micelles in an environment similar to that in which they normally exist.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 6
    ISSN: 1573-904X
    Keywords: muscle ; genetic vaccines ; immune response ; polyvinylpyrrolidone ; growth hormone ; and needle-free injection device
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Purpose. A plasmid-based gene expression system was complexed with protective, interactive, and non-condensing (PINC™) polymer system and administered with Medi-Jector™, a needle-free injection device (NFID), to achieve high and sustained levels of antigen-specific antibodies in blood circulation. Methods. Human growth hormone (hGH) or bacterial β-galactosidase gene expression plasmids driven by a cytomegalovirus (CMV) promoter were formulated in saline or complexed with a PINC polymer, polyvinylpyrrolidone (PVP), and intramuscularly or subcutaneously administered into dogs and pigs using a 22-gauge needle or a NFID. The hGH-specific IgG titers in serum were measured by an ELISA. β-galactosidase expression was measured in injected muscles by an enzymatic assay or immunohistochemistry. The effect of NFID on DNA stability and topology was assessed by gel electrophoresis. Results. Intramuscular (i.m.) or subcutaneous (s.c.) injection of a hGH expression plasmid pCMV-hGH (0.05-0.5 mg/kg) in dogs and pigs elicited antigen-specific IgG antibody titers to expressed hGH. With both routes of injection, pDNA delivery by a NFID was superior to pDNA injection by needle. The magnitude of hGH-specific IgG titers with NFID was 15−20-fold higher than needle injection when pDNA was complexed with PVP, and only 3−4-fold higher with pDNA in saline. The transfection efficiency in the injected muscle, as measured by β-galaclosidase expression, following i.m. injection of pCMV-β-galaclosidase/PVP, was not significantly different between needle and NFID-injected groups. Conclusions. These data demonstrate that the combination of pDNA/ PVP complexes and a NFID act synergistically to achieve high and sustained levels of antigen-specific IgG response to expressed antigen. This gene delivery approach may offer advantage over needle injection of naked DNA for the development of genetic vaccines.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Pharmaceutical research 14 (1997), S. 853-859 
    ISSN: 1573-904X
    Keywords: non-viral gene delivery ; plasmid ; cationic liposomes ; formulation ; transfection
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Gene delivery systems are designed to control the location of administered therapeutic genes within a patient's body. Successful in vivo gene transfer may require (i) the condensation of plasmid and its protection from nuclease degradation, (ii) cellular interaction and internalization of condensed plasmid, (iii) escape of plasmid from endosomes (if endocytosis is involved), and (iv) plasmid entry into cell nuclei. Expression plasmids encoding a therapeutic protein can be, for instance, complexed with cationic liposomes or micelles in order to achieve effective in vivo gene transfer. A thorough knowledge of pharmaceutics and drug delivery, bio-engineering, as well as cell and molecular biology is required to design optimal systems for gene therapy. This mini-review provides a critical discussion on cationic lipid-based gene delivery systems and their possible uses as pharmaceuticals.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 8
    ISSN: 1573-904X
    Keywords: muscle ; DNA plasmid ; gene delivery system ; polyvinyl pyrrolidone ; polyvinyl alcohol ; non-viral gene therapy ; gene expression system
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Purpose. DNA plasmids (pDNA) can be taken up by and expressed in striated muscle after direct intramuscular injection. We have developed interactive polymeric gene delivery systems that increase pDNA bioavailability to muscle cells by both protecting pDNA from nucleases and controlling the dispersion and retention of pDNA in muscle tissue. Methods. A DNA plasmid, containing a CMV promoter and a β-galactosidase reporter gene (CMV-β-gal), was injected either in saline or formulated in polyvinyl pyrrolidone (PVP) and polyvinyl alcohol (PVA) solutions. Interactions between PVP and pDNA were assessed by dynamic dialysis, Isothermal Titration Calorimetry (ITC), and Fourier-Transformed Infra Red (FT-IR) spectroscopy. Formulations (50 µl) were injected into rat tibialis muscles after surgical exposure. Immuno-histochemistry for β-gal was used to visualize the sites of expression in muscle. Results. β-gal expression using pDNA in saline reached a plateau while β-gal expression using PVP formulations increased linearly in the dose range studied (12.5–150 µg pDNA injected) and resulted in an increase in the number and distribution of cells expressing β-gal. The interaction between PVP and pDNA was found to be an endothermic process governed largely by hydrogen-bonding and results in protection of pDNA from extracellular nucleases. Conclusions. Significant enhancement of gene expression using interactive polyvinyl-based delivery systems has been observed. The improved tissue dispersion and cellular uptake of pDNA using polyvinyl-based systems after direct injection into muscle is possibly due to osmotic effects.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 9
    ISSN: 1573-904X
    Keywords: pulmonary gene medicine ; plasmid ; aerosol ; ultrasonic nebulization
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Purpose. This study relates to the development of gene therapies for the treatment of lung diseases. It describes for the first time the use of ultrasonic nebulization for administration of plasmid/lipid complexes to the lungs to transfect lung epithelial cells. Methods. Plasmid complexed to cationic liposomes at a specific stoichiometric ratio was nebulized using an ultrasonic nebulizer. We assessed: (i) the stability of plasmid and plasmid/lipid complexes to ultrasonic nebulization, (ii) the in vitro activity of plasmid in previously nebulized plasmid/lipid complex, (iii) the in vivo transgene expression in lungs following intratracheal instillation of nebulized plasmid/lipid formulations compared to un-nebulized complexes, (iv) the emitted dose from an ultrasonic nebulizer using plasmid/lipid complexes of different size, and (v) the transgene expression in lungs following oral inhalation of aerosolized plasmid/lipid complex generated using an ultrasonic nebulizer. Results. Integrity of plasmid formulated with cationic lipids, and colloidal stability of the plasmid/lipid complex were maintained during nebulization. In contrast, plasmid alone formulated in 10% lactose was fragmented during nebulization. The efficiency of transfection of the complex before and after nebulization was comparable. Nebulization produced respirable aerosol particles. Oral exposure of rodents for 10 minutes to aerosol produced from the ultrasonic nebulizer resulted in transgene expression in lungs in vivo. Conclusions. The performance characteristics of the ultrasonic nebulizer with our optimized plasmid/lipid formulations suggests that this device can potentially be used for administering gene medicines to the airways in clinical settings for the treatment of respiratory disorders.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 10
    ISSN: 1573-904X
    Keywords: gene transfer ; airways ; cationic lipids ; surface charge ; co-lipid content ; topology
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Purpose. Cationic lipids are capable of transferring foreign genes to the pulmonary epithelium in vivo. It is becoming increasingly clear that factors other than lipid molecular structure also influence efficiency of delivery using cationic lipid systems. This study is aimed at evaluating the effect of formulation variables such as cationic lipid structure, cationic lipid/DNA ratio, particle size, co-lipid content and plasmid topology on transgene expression in the lung. Methods. The effect of varying the surface and colloidal properties of cationic lipid-based gene delivery systems was assessed by intratracheal instillation into rats. An expression plasmid encoding chloramphenicol acetyl transferase (CAT) was used to measure transgene expression. Results. Cationic lipid structure, cationic lipid/DNA ratio, particle size, co-lipid content and topology of the plasmid, were found to significantly affect transgene expression. Complexation with lipids was found to have a protective effect on DNA integrity in bronchoalveolar lavage fluid (BALF). DNA complexed with lipid showed enhanced persistence in rat lungs as measured by quantitative polymerase chain reaction. Conclusions. Fluorescence microscopy analysis indicated that the instilled formulation reaches the lower airways and alveolar region. Data also suggests cationic lipid-mediated gene expression is primarily localized in the lung parenchyma and not infiltrating cells isolated from the BALF.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...