Fungal development and secondary metabolism is intimately associated via activities of the fungi-specific velvet family proteins including VeA, VosA, VelB and VelC. Among these, VelC has not been characterized in Aspergillus nidulans. In this study, we characterize the role of VelC in asexual and sexual development in A. nidulans. The velC mRNA specifically accumulates during the early phase of sexual development. The deletion of velC leads to increased number of conidia and reduced production of sexual fruiting bodies (cleistothecia). In the velC deletion mutant, mRNA levels of the brlA, abaA, wetA and vosA genes that control sequential activation of asexual sporulation increase. Overexpression of velC causes increased formation of cleistothecia. These results suggest that VelC functions as a positive regulator of sexual development. VelC is one of the five proteins that physically interact with VosA in yeast two-hybrid and GST pull down analyses. The ΔvelC ΔvosA double mutant produced fewer cleistothecia and behaved similar to the ΔvosA mutant, suggesting that VosA is epistatic to VelC in sexual development, and that VelC might mediate control of sex through interacting with VosA at specific life stages for sexual fruiting.

The aim of this study was to develop an aqueous parenteral formulation containing itraconazole (ITZ) using an o/w microemulsion system. A mixture of benzyl alcohol and medium chain triglyceride (3/1) was chosen as the oil phase. Pseudoternary phase diagrams of the microemulsion formations were constructed in order to determine the optimum ratio of oils, the concentration range of surfactant and cosurfactant and the optimum ratio between them. Consequently, the suitability of the chosen microemulsion system as a parenteral formulation was evaluated using droplet size analysis and hemolysis tests. Among the surfactants and cosurfactants screened, a mixture of polyoxyethylene (50) hydrogenated castor oil and ethanol (3/1) showed the largest o/w microemulsion region in the phase diagram. The average droplet size of the microemulsions was < 150 nm, and the hemolysis test showed this formulation to be nontoxic to red blood cells. The pharmacokinetic profiles of the ITZ-microemulsion for itraconazole and its major metabolite, hydroxyitraconazole, were compared with those of a PEG 400 solution and cyclodextrin formulations in rats. Overall, these results highlight the potential of an ITZ-microemulsion formulation for the parenteral route.

The effects of vehicles and penetration enhancers on the skin permeation of clebopride were evaluated using Franz type diffusion cells fitted with excised rat dorsal skins. The binary vehicle system, diethylene glycol monoethyl ether/isopropyl myristate (40/60, w/w), significantly enhanced the skin permeation rate of clebopride. The skin permeation enhancers, oleic acid and ethanol when used in the binary vehicle system, resulted in relatively high clebopride skin permeation rates. A gel formulation consisting of 1.5% (w/w) clebopride, 5% (w/w) oleic acid, and 7% (w/w) gelling agent with the binary vehicle system resulted in a permeation rate of 28.90 microg/cm2/h. Overall, these results highlight the potential of clebopride formulation for the transdermal route.

The aim of this study was to examine the in vitro/in vivo relationship of the drug release behavior of a sustained-release formulation of gabapentin. The immediate-release formulation was used as the reference formulation. The dissolution test was employed using pH 1.2, 4.0, or 6.8 buffer solution, or water, to determine the in vitro release behaviors of gabapentin tablets. Gabapentin was released completely within 1 h from the immediate-release tablet and released for 12 h from the sustained-release tablet. A single dose (600 mg) of each formulation was orally administered to four beagle dogs under fasted conditions, and the pharmacokinetic parameters were calculated. Although the sustained-release tablet did not disintegrate and had slow drug release characteristics, it showed similar pharmacokinetic parameters to the immediate-release tablet, which rapidly disintegrated and showed fast drug release. Thus, the in vivo release of gabapentin did not correlate with in vitro release of drug.

Acamprosate calcium is a highly soluble drug with low permeability that is used to maintain abstinence in alcohol-dependent patients. The aim of this study was to investigate the relationship between in vitro and in vivo behaviors of acamprosate from enteric-coated tablets. The in vitro release behavior of acamprosate tablets in pH 6.8 buffer solution was determined in three dissolution conditions, 50 and 150 rpm (paddle method) and 180 rpm (basket method). The results of this in vitro experiment indicated that acamprosate tablets hardly disintegrated, and drug dissolution was retarded despite the extremely hydrophilic nature of the drug. A single dose (333 mgx2 tablets) of each formulation was orally administered to four beagle dogs under fasting conditions, and the pharmacokinetic parameters were calculated. The mean AUC0-48, Cmax, Tlag and Tmax for the two types of tablets ranged from 41.5-53.6 microg.h/mL, 4.3-4.5 microg/mL, 2.0-2.5 h and 3.8-4.0 h, respectively. In conclusion, it is suggested that retarded drug release from the tablets and the low drug permeability may result in poor absorption and erratic bioavailability of this drug in humans.