RESUMO
Clarithromycin [CLM] is a member of macrolide family with broad spectrum antibiotic activity. It is practically insoluble in water and its poor solubility is pH dependent. In this study, series of nanosuspensions containing CLM and stabilizer such as HPMC, NaCMC, polysorbate 80, poloxamer 188 and polyvinyl alcohol in various ratios were prepared using sonoprecipitation method. Briefly, CLM was dissolved in acid solution and the pH of solution was raised under sonication and the effects of different stabilizers on particle size of nanoparticles were evaluated. Characterization of nanoparticles in terms of size, polydispersity index, zeta potential, differential scanning calorimetery and dissolution studies was performed. Antimicrobial activity of CLM nanosuspension was compared with coarse powder by using an agar well diffusion method. The results showed that HPMC was more efficient in size reduction of particles and presence of HPMC E5 with ratio of 3:5 to CLM in formulation led to develop the stable nanosuspension with particle size of 340 nm. The obtained nanosuspension successfully showed enhanced dissolution rate and antimicrobial activity
RESUMO
Oxidative stress in teratozoospermic semen samples caused poor assisted reproductive techniques [ART] outcomes. Among antioxidants, ascorbic acid is a naturally occurring free radical scavenger and as such its presence assists various other mechanisms in decreasing numerous disruptive free radical processes. The main goal of this study was to evaluate potential protective effects of ascorbic acid supplementation during in vitro culture of teratozoospermic specimens. Teratozoospermic semen samples that collected from 15 volunteers were processed, centrifuged and incubated at 37°C until sperm swimmed-up. Supernatant was divided into four groups and incubated at 37°C for one hour under different experimental conditions: Control, 10 micro m A23187, 600 micro m ascorbic acid and 10 micro m A23187+600 micro m ascorbic acid. After incubation sperm motility, viability, acrosome reaction, DNA damage and malondialdehyde levels were evaluated. Our results indicated that after one hour incubation, ascorbic acid significantly reduced malondialdehyde level in ascorbic acid group [1.4 +/- 0.11 nmol/ml] compared to control group [1.58 +/- 0.13 nmol/ml] [p<0.001]. At the end of incubation, progressive motility and viability in ascorbic acid group [64.5 +/- 8.8% and 80.3 +/- 6.4%, respectively] were significantly [p<0.05 and p<0.001, respectively] higher than the control group [54.5 +/- 6.8% and 70.9 +/- 7.3%, respectively]. A23187 significantly [p<0.0001] increased acrosome reaction in A23187 group [37.3 +/- 5.6%] compared to control group [8.5 +/- 3.2%] and this effect of A23187 attenuated by ascorbic acid in ascorbic acid+A23187 group [17.2 +/- 4.4%]. DNA fragmentation in ascorbic acid group [20 +/- 4.1%] was significantly [p<0.001] lower than controls [28.9 +/- 4.6%]. In vitro ascorbic acid supplementation during teratozoospermic semen processing for ART could protect teratozoospermic specimens against oxidative stress, and it could improve ART outcome