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Background and Objective: An increased risk of invasive infections with encapsulated bacteria such as Streptococcus pneumoniae has been described among splenectomized patients. Pneumococcal vaccination has been recommended in these patients. In this study, the serum antibody response to pneumococcal polysaccharide antigens in splenectomized patients with idiopathic thrombocytopenic purpura (ITP) or trauma who immunized with Pneumovax 23 was evaluated. Materials and Methods: This case - control study was performed on two groups of patients including fifteen cases of trauma patients (11 male, 4 female) and twenty patients with ITP (10 male, 10 female) along with 40 healthy volunteers as controls who were immunized with Pneumovax 23 to prevent pneumococcal infections. All patients received the pneumococcal vaccine before splenectomy. The serum antibody response (IgG and IgG2) to pneumococcal antigens was determined by enzyme-linked immunosorbent assay (ELISA) technique prior to vaccination and 4 weeks post-vaccination. Analyzing of data was performed using student t-test and linear regression test. Results: The mean of post-vaccination IgG or IgG2 titer to the pneumococcal antigens in ITP patient group was significantly lower than those in controls or in trauma group (P<0.05). No significant differences in IgG or IgG2 antibody titer increase were found between trauma group and healthy control group. Response to immunization was poor in 9 of 20 ITP patients. Conclusion: This study indicated that 45 percent of patients suffered from ITP who have undergone splenectomy responded poorly to pneumococcal antigens.

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Background and Objective: With respect to the antioxidant role of melatonin and retinoic acid, it seems to be effective both in the maturation and embryonic development. This study was done to investigate the effect of combination of melatonin and All-Trans retinoic acid (RA) on maturation, fertilization and embryonic development of immature mouse oocytes. Methods: In this experimental study, cumulus - oocyte complex (COCs) were recovered from 4-6 week old female mice NMRI and were divided into 6 maturation medium groups including control, sham, experiment 1(melatonin 100 nM, 1 and 2 µM), experiment 2 (retinoic acid 1, 2, 4, 6 µM), experiment 3 (melatonin 2 µM+RA 4 µM), experiment 4 (Mel 100nM + retinoic acid 4µM). The maturation rate was recorded after 24 hours of culture in a humidified atmosphere of 5% CO2 at 37°C. The matured oocytes were fertilized with sperm. Fertilization and embryonic development rates to the blastocyst stage were recorded. Results: Maturation rate in the control and sham groups were 50.6% and 49.4%, respectively. Maturation rate were 54.3%, 54.8%, 59.9% in melatonin group with concentrations of 100 nM, 1 and 2 µM, respectively. Maturation rate were 51.6%, 51%, 59% and 49.6% in t-RA group with concentrations of 1, 2, 4, 6 μM. Maturation rate were 60.4% and 54.2% in the experiment 3 and 4 groups, respectively. The maturation rates in the melatonin 2 µM, retinoic acid 4 µM and experiment 3 significantly increased in compare to control (P<0.05). The embryonic development rate in the melatonin with 100nM concentration and 4 µM of retinoic acid increased significantly compared to controls (P<0.05). Although, embryonic development rate in experiment 3 was higher than control, but lower in compare to melatonin 100 nM and the retinoic acid 4 µM. The embryonic development rate in experiment 4 significantly increased in compare to control (P<0.05). Conclusion: Combination of melatonin and All-Trans retinoic acid in medium culture increase maturation rate and improved embryonic development in dose dependent manner.