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Potential Vehicles (potential + vehicle)
Selected AbstractsCell-penetrating peptide TAT-mediated delivery of acidic FGF to retina and protection against ischemia,reperfusion injury in ratsJOURNAL OF CELLULAR AND MOLECULAR MEDICINE, Issue 7 2010Yi Wang Abstract The development of non-invasive ocular drug delivery systems is of practical importance in the treatment of retinal disease. In this study, we evaluated the efficacy of transactivator of transcription protein transduction domain (TAT-PTD, TAT49,57) as a vehicle to deliver acidic FGF (aFGF) to retina in rats. TAT-conjugated aFGF-His (TAT-aFGF-His) exhibited efficient penetration into the retina following topical administration to the ocular surface. Immunochemical staining with anti-His revealed that TAT-aFGF-His proteins were readily found in the retina (mainly in the ganglion cell layer) at 30 min. and remained detectable for at least 8 hrs after administration. In contrast, His+ proteins were undetectable in the retina after topical administration of aFGF-His, indicating that aFGF-His cannot penetrate the ocular barrier. Furthermore, TAT-aFGF-His, but not aFGF-His, mediated significant protection against retinal ischemia,reperfusion (IR) injury. After IR injury, retina from TAT-aFGF-His-treated rats showed better-maintained inner retinal layer structure, reduced apoptosis of retinal ganglion cells and improved retinal function compared to those treated with aFGF-His or PBS. These results indicate that conjugation of TAT to aFGF-His can markedly improve the ability of aFGF-His to penetrate the ocular barrier without impairing its biological function. Thus, TAT49,57 provides a potential vehicle for efficient drug delivery in the treatment of retinal disease. [source] Investigation of the genetic diversity among isolates of Salmonella enterica serovar Dublin from animals and humans from England, Wales and IrelandJOURNAL OF APPLIED MICROBIOLOGY, Issue 5 2002E. Liebana Aims: To assess the degree of genetic diversity among animal Salmonella Dublin UK isolates, and to compare it with the genetic diversity found among human isolates from the same time period. Methods and Results: One hundred isolates (50 human and 50 animal) were typed using plasmid profiling, XbaI-pulsed field gel electrophoresis (PFGE) and PstI- SphI ribotyping. Antimicrobial resistance data to 16 antibiotics was presented, and the presence of class-I integrons was investigated by real-time PCR. Seven different plasmid profiles, 19 ribotypes and 21 PFGE types were detected. A combination of the three methods allowed clear differentiation of 43 clones or strains. Eighteen isolates were resistant to at least one antimicrobial; five of them were multi-resistant and of these, only three presented class I integrons. Conclusions: Ribotyping data suggest the existence of at least three very different clonal lines; the same distribution in well-defined groups was not evident from the PFGE data. The existence of a variety of clones in both animals and humans has been demonstrated. A few prevalent clones seem to be widely disseminated among different animal species and show a diverse geographical and temporal distribution. The same clones were found in animals and humans, which may infer that both farm and pet animals may act as potential vehicles of infection for humans. Some other clones seem to be less widely distributed. Clustering analysis of genomic fingerprints of Salmonella Dublin and Salm. Enteritidis isolates confirms the existence of a close phylogenetic relationship between both serotypes. Significance and Impact of the Study: This paper describes the utility of a multiple genetic typing approach for Salm. Dublin. It gives useful information on clonal diversity among human and animal isolates. [source] Acyclovir delivery matrices based on poly(ethylene glycol)/chitosan semi-interpenetrating networksJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 6 2007O. Diez-Sales Abstract Chitosan matrix systems have been studied as potential vehicles for the prolonged release of acyclovir (ACV). The influence of chitosan concentration (from 0.83% to 1.67%) on viscoelastic properties of formulations with and without glyoxal was analyzed. For chitosan-poly(ethylene glycol) 400 formulations loss modulus (G,) are greater than storage modulus (G,). This corresponds to the characteristic behavior of nonstructured systems. When glyoxal was added to the chitosan-poly(ethylene glycol) 400 formulations, gelled matrix was obtained (i.e., G, is higher than G,), except for the lowest chitosan concentration. ACV release rates for the both types of systems, with and without glyoxal, were also determined. The ACV diffusion coefficient values from matrices are less than for the respective formulation without glyoxal and it was found to depend on the crosslink density within the matrices. Viscoelastic parameters, dynamic moduli (G,, G,), and complex viscosity (,*), were correlated with the ACV diffusion coefficients (D). The complex viscosity (,*) could be used as a parameter of predictive value for the release rate of drugs. © 2007 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 96:1653,1657, 2007 [source] Proteomic profiling of exosomes: Current perspectivesPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 19 2008Richard J. Simpson Professor Abstract Exosomes are 40,100,nm membrane vesicles of endocytic origin secreted by most cell types in vitro. Recent studies have shown that exosomes are also found in vivo in body fluids such as blood, urine, amniotic fluid, malignant ascites, bronchoalveolar lavage fluid, synovial fluid, and breast milk. While the biological function of exosomes is still unclear, they can mediate communication between cells, facilitating processes such as antigen presentation and in trans signaling to neighboring cells. Exosome-like vesicles identified in Drosophila (referred to as argosomes) may be potential vehicles for the spread of morphogens in epithelia. The advent of current MS-based proteomic technologies has contributed significantly to our understanding of the molecular composition of exosomes. In addition to a common set of membrane and cytosolic proteins, it is becoming increasingly apparent that exosomes harbor distinct subsets of proteins that may be linked to cell-type associated functions. The secretion of exosomes by tumor cells and their implication in the transport and propagation of infectious cargo such as prions and retroviruses such as HIV suggest their participation in pathological situations. Interestingly, the recent observation that exosomes contain both mRNA and microRNA, which can be transferred to another cell, and be functional in that new environment, is an exciting new development in the unraveling exosome saga. The present review aims to summarize the physical properties that define exosomes as specific cell-type secreted membrane vesicles. [source] | ||||||||||