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<p><b>OBJECTIVE</b>To prepare ginkgolide B-loaded self microemulsifying drug delivery system (SMEDDS) and evaluate its quality.</p><p><b>METHOD</b>The solubility of ginkgolide B in different oil, surfactant and co-surfactant were measured by HPLC-ESI-MS. The GB-SMEDDS formulation was optimized by the self emulsifying efficiency of various combinations of oil and mix-surfactant evaluated by using pseudo-temary phase diagram. The preliminary stability of GB-SEMEDDS was evaluated by the variety of loading rate of GB and dispersed medium. The morphology, the particle size and the formulation stability were evaluated after diluting by 0.1 mol x L(-1) HCl.</p><p><b>RESULT</b>The blank self microemulsified system was composed of ethyl oleate-( cremophor EL-lecithin-ethanol, 4: 1:2) (40: 60), the loading dosage was 2.5%. Little influence of GB and emulsified medium was observed on the stability of GB-SEMDDS. After diluted with 0.1 mol x L(-1) HCl, the morphology of the microemulsion was homogeneous small spherical drops observed under electro-microscope. The particle size was (41.6 +/- 1.11) nm, the self microemulsifing time was around 2 min. The formulation was stable within 8 h, without significant changes in particle size and separation of drugs.</p><p><b>CONCLUSION</b>GB-SMEDDS is easy to prepare and its quality is stable. The solubility of GB was significantly improved by SMEDDS.</p>
Subject(s)
Chemistry, Pharmaceutical , Methods , Drug Delivery Systems , Methods , Emulsions , Chemistry , Ginkgolides , Chemistry , Pharmacokinetics , Lactones , Chemistry , Pharmacokinetics , Particle Size , Solubility , Surface-Active Agents , ChemistryABSTRACT
AIM: To observe the effect of ginkgolide B (CB) on the intracellular calcium ion concentration ( [ Ca~(2+) ]_i) and mitochondrial function of cultured rat retinal neurons in vitro. METHODS: in vitro primary culture of rat retinal neurons was used in the experiment. The apoptosis model of glutamate - induced retinal neurons was established and co - cultured with ginkgolide B. The [ Ca~(2+) ]_i and mitochondrial membrane potential of the retinal neurons were detected by laser scanning confocal microscope. RESULTS: Glutamate decreased the survival rate of retinal neurons, increased the apoptosis and the [ Ca~(2+) ]_i, lowered the mitochondrial membrane potential. The [ Ca~(2+) ]_i was clearly diminished and the mitochondrial membrane potential was significantly increased with the GB intervention, and the apoptosis decreased significantly. CONCLUSION: GB protects retinal neurons from glutamate induced neurotoxicity. The effect of GB on retinal neurons might be due to its ability to decrease the [Ca~(2+) ]_i and increase mitochondrial membrane potential.
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Objective To evaluate the therapeutic effects of vitrectomy on chronic and refractory Beh et′s diseases. Methods The clinical data of 8 patients (10 eyes) with Beh et′s diseases from 0.5 to 3 years after vitrectomy were retrospectively analyzed. Pre-and post-operative visual acuity, control of inflammation after the surgery, and the recurrence were observed and analyzed. Both of the eyes were involved in all of the patients, including complete Beh et′s diseases in 5 and incomplete in 3. Results Vitreous opacity and liquefaction were found in all of the involved eyes, dark retina and thin retinal vessels were seen in most of the eyes, and vascular obstruction or sheath-like changes in different degrees were detected in some eyes. Improvement of visual acuity was observed in all of the eyes which had undergone the treatment after the operation. There was significant difference between the visual acuity before the surgery and at the 1st and 2nd week and the 1st and 6th month after the surgery. During the follow-up period, recurrence of the inflammation was found in 3 eyes within 1 month and in 6 eyes within 6 months; no recurrence was found in 4 eyes after the operation. No acute recurrence of inflammation was found after operation in the involved eyes. Conclusion Vitrectomy for chronic and refractory Beh et′s diseases may improve the visual acuity of the involved eyes, and the surgery is safe and effective.
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AIM:To observe the effect of ginkgolide B (GB) on the intracellular calcium ion concentration ([Ca2+]i) and mitochondrial function of cultured rat retinal neurons in vitro.METHODS:in vitro primary culture of rat retinal neurons was used in the experiment. The apoptosis model of glutamate-induced retinal neurons was established and co-cultured with ginkgolide B. The [Ca2+]i and mitochondrial membrane potential of the retinal neurons were detected by laser scanning confocal microscope.RESULTS:Glutamate decreased the survival rate of retinal neurons,increased the apoptosis and the [Ca2+]i,lowered the mitochondrial membrane potential. The [Ca2+]i was clearly diminished and the mitochondrial membrane potential was significantly increased with the GB intervention,and the apoptosis decreased significantly.CONCLUSION:GB protects retinal neurons from glutamate induced neurotoxicity. The effect of GB on retinal neurons might be due to its ability to decrease the [Ca2+]i and increase mitochondrial membrane potential.