36 research outputs found
FORMULATION AND CHARACTERIZATION OF FLUCONAZOLE LOADED OLIVE OIL NANOEMULSIONS
Present study was carried out to develop and evaluate olive oil based nano-emulsion for transdermal delivery of fluconazole, a bistriazole based antifungal agent with poor water solubility and lipophilicity. Olive oil, a natural non-irritating, non-toxic proposed permeation enhancer, is known to have some antifungal activity as well. Screening of common emulsifiers like Tweens (Tween 20, tween 60, tween 80), Spans (span 60, span 80), brij 35, puronic 127, and poloxamer 188 were done based on solubility of fluconazole in these surfactants followed by their efficiency to emulsify olive oil in water. Co-emulsifiers such as glycols (polyethylene glycol 200, polyethylene glycol 400, propylene glycol), and short chain alcohols (ethanol, propanol, butanol and octanol) were also screened similarly. Tween 80 and butanol were selected as emulsifier and co-emulsifier respectively to formulate nano-emulsion by aqueous titration method. However, separation was observed after 24 hours. Therefore, span 80 was added as an auxiliary emulsifier to improve emulsification efficiency. Finally, a blend of tween 80, span 80 and butanol was optimized as emulsifier (56 % wt/wt) to emulsify 9 % wt/wt of olive oil in 33 % wt/wt water. Pseudo-ternary phase diagram was employed to identify and optimize the components. Optimized formulation based on phase separation and thermokinetic stability was characterized for globule size, size distribution, zeta potential, viscosity, refractive index and pH. Globule size analysis by zetasizer nano ZS was further confirmed by transmission electron microscopy. Permeation flux of fluconazole from optimized formulation through artificial skin was approximately three fold higher than the control. In conclusion, developed olive oil based nano-emulsion of fluconazole demonstrated promising solubility, permeability and stability.
Keywords: Fluconazole, olive oil, nano-emulsion, transdermal permeatio
Trichloroethene metabolite dichloroacetyl chloride induces apoptosis and compromises phagocytosis in Kupffer Cells: Activation of inflammasome and MAPKs.
Exposure to trichloroethene (TCE), an occupational and ubiquitous environmental contaminant, is associated with the development of several autoimmune diseases, including autoimmune hepatitis (AIH). However, mechanisms contributing to TCE-mediated AIH are not known. Earlier, we have shown that dichloroacetyl chloride (DCAC), one of the reactive metabolites of TCE with strong acylating capability, can elicit an autoimmune response at much lower dose than TCE in female MRL+/+ mice. Furthermore, Kupffer cells (KCs), the liver resident macrophages, are crucial for hepatic homeostasis, but can also participate in the immunopathogenesis of AIH. However, contribution of KCs in TCE-mediated AIH and the underlying mechanisms are not understood. We hypothesized that increased apoptosis and delayed clearance of apoptotic bodies, due to compromised KC function, will result in the breakdown of self-tolerance, autoimmunity, and ultimately AIH. Therefore, using an in vitro model of immortalized mouse KCs, we investigated the contribution of DCAC in TCE-mediated AIH. KCs were treated with different concentrations of DCAC and apoptosis was measured by Annexin V and PI staining. Also, the impact of DCAC on phagocytic potential of KCs was evaluated. Furthermore, markers of inflammasome (NLRP3 and caspase1) were analyzed by real-time PCR and Western blot analysis. DCAC treatment resulted in significantly increased early and late-stage apoptosis, accompanied with inflammasome activation (NLRP3 increases). DCAC treatment resulted in decreased phagocytic function of KCs in a dose-dependent manner, with reduced MFG-E8 levels (phagocytotic function). Furthermore, DCAC exposure led to induction of phos-ERK and phos-AKT signaling. These findings suggest that DCAC induces apoptosis and inflammasome activation, while compromising the phagocytic function of KCs. Our data support that increased apoptosis and impaired KC function by DCAC could be contributory to TCE-mediated AIH
Nitrosative stress and nitrated proteins in trichloroethene-mediated autoimmunity.
Exposure to trichloroethene (TCE), a ubiquitous environmental contaminant, has been linked to a variety of autoimmune diseases (ADs) including SLE, scleroderma and hepatitis. Mechanisms involved in the pathogenesis of ADs are largely unknown. Earlier studies from our laboratory in MRL+/+ mice suggested the contribution of oxidative/nitrosative stress in TCE-induced autoimmunity, and N-acetylcysteine (NAC) supplementation provided protection by attenuating oxidative stress. This study was undertaken to further evaluate the contribution of nitrosative stress in TCE-mediated autoimmunity and to identify proteins susceptible to nitrosative stress. Groups of female MRL +/+ mice were given TCE, NAC or TCE + NAC for 6 weeks (TCE, 10 mmol/kg, i.p., every 4th day; NAC, ∼ 250 mg/kg/day via drinking water). TCE exposure led to significant increases in serum anti-nuclear and anti-histone antibodies together with significant induction of iNOS and increased formation of nitrotyrosine (NT) in sera and livers. Proteomic analysis identified 14 additional nitrated proteins in the livers of TCE-treated mice. Furthermore, TCE exposure led to decreased GSH levels and increased activation of NF-κB. Remarkably, NAC supplementation not only ameliorated TCE-induced nitrosative stress as evident from decreased iNOS, NT, nitrated proteins, NF-κB p65 activation and increased GSH levels, but also the markers of autoimmunity, as evident from decreased levels of autoantibodies in the sera. These findings provide support to the role of nitrosative stress in TCE-mediated autoimmune response and identify specific nitrated proteins which could have autoimmune potential. Attenuation of TCE-induced autoimmunity in mice by NAC provides an approach for designing therapeutic strategies
Kinetics and Photodegradation Study of Aqueous Methyl tert-Butyl Ether Using Zinc Oxide: The Effect of Particle Size
Zinc oxide of different average particle sizes 25 nm, 59 nm, and 421 nm as applied in the photodegradation of MTBE. This study was carried out in a batch photoreactor having a high pressure mercury lamp. Zinc oxide of particle size of 421 nm was found to be the most effective in degrading MTBE in an aqueous solution. On using this type of ZnO in a solution of 100 ppm MTBE, the concentration of MTBE has decreased to 5.1 ppm after a period of five hours. The kinetics of the photocatalytic degradation of MTBE was found to be a first order reaction
Combining Yeast Display and Competitive FACS to Select Rare Hapten-Specific Clones from Recombinant Antibody Libraries
The development of antibodies to
low molecular weight haptens remains
challenging due to both the low immunogenicity of many haptens and
the cross-reactivity of the protein carriers used to generate the
immune response. Recombinant antibodies and novel display technologies
have greatly advanced antibody development; however, new techniques
are still required to select rare hapten-specific antibodies from
large recombinant libraries. In the present study, we used a combination
of phage and yeast display to screen an immune antibody library (size,
4.4 × 10<sup>6</sup>) against hapten markers for petroleum contamination
(phenanthrene and methylphenanthrenes). Selection via phage display
was used first to enrich the library between 20- and 100-fold for
clones that bound to phenanthrene–protein conjugates. The enriched
libraries were subsequently transferred to a yeast display system
and a newly developed competitive FACS procedure was employed to select
rare hapten-specific clones. Competitive FACS increased the frequency
of hapten-specific scFvs in our yeast-displayed scFvs from 0.025 to
0.005% in the original library to between 13 and 35% in selected pools.
The presence of hapten-specific scFvs was confirmed by competitive
ELISA using periplasmic protein. Three distinct antibody clones that
recognize phenanthrene and methylphenanthrenes were selected, and
their distinctive binding properties were characterized. To our knowledge,
these are first antibodies that can distinguish between methylated
(petrogenic) versus unmethylated (pyrogenic) phenanthrenes; such antibodies
will be useful in detecting the sources of environmental contamination.
This selection method could be generally adopted in the selection
of other hapten-specific recombinant antibodies
Summary of nitrated proteins in control, TCE- and TCE+NAC-treated mice.
<p>*Spot numbers are the same as shown in the <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0098660#pone-0098660-g005" target="_blank">Fig.5</a>; <sup>#</sup>The accession number are in NCBI database; <sup>+</sup>A score >64 was considered significant (p<0.05) for protein identified from the database.</p