[Inhibition of Toxoplasma gondii excretory - secretory antigens on growth of murine Lewis lung carcinoma].

OBJECTIVE: To investigate the effect of Toxoplasma gondii excretory-secretory antigens (ESA) on CD4+ CD25+ Foxp3+ T (Treg) cells in mice carrying Lewis lung carcinoma, and examine the inhibitory effect of T. gondii ESA on tumor growth. METHODS: C57BL/6 mice were randomly assigned into the PBS group (n = 14) and the Lewis group (n = 34). Mice in the Lewis group were subcutaneously injected with 2 × 105 Lewis lung carcinoma cells in the right axilla, while animals in the PBS group were injected with the same volume of sterile PBS. On day 7 post-injection (D7), mice in the PBS group were further divided into the PBS2 group and the PBS2 + ESA group, of 7 mice in each group, and mice in the Lewis group were further divided into the Lewis2 group and the Lewis2 + ESA group, of 17 mice in each group. Then, mice in the PBS2 + ESA group and the Lewis2 + ESA group were intraperitoneally injected with 100 µL of ESA. The mouse spleen coefficient was calculated in each group 7 days post-injection with ESA, and the changes of Treg cell counts and the long-term tumor growth were measured in tumor-bearing mice. RESULTS: The spleen coefficient was significantly greater in the PBS2 + ESA group and the Lewis2 + ESA group than in the PBS2 (0.66% ± 0.09% vs. 0.30% ± 0.02%, P < 0.05) and Lewis2 groups (0.69% ± 0.07% vs. 0.33% ± 0.03%, P < 0.05) 7 days post-treatment with ESA, respectively, and the percentage of splenic Treg cells in splenocytes was significantly lower in the PBS2 + ESA group and the Lewis2 + ESA group than in the PBS2 (1.28% ± 0.14% vs. 2.06% ± 0.07%, P < 0.05) and Lewis2 groups (1.58% ± 0.14% vs. 2.44% ± 0.23%, P < 0.05), respectively. T. gondii ESA treatment caused a delay in tumor growth, and the tumor size was significantly smaller in the Lewis2 + ESA group than in the Lewis2 group (P < 0.05). CONCLUSIONS: T. gondii ESA may reduce the proportion of splenic Treg cells in splenocytes and inhibit tumor growth in mice carrying Lewis lung carcinoma.

[Experience and analysis of excellent works of human parasitology in national medical colleges and universities].

Teaching competition is an effective way for college and university teachers to improve their teaching skills. Based on the teaching practice and experience in medical parasitology, this paper discusses several key issues in teaching competition including topics, teaching designs and teaching methods. It provides references for the teachers in department of parasitology of universities and colleges to improve the quality of classroom teaching.

The effects of growth hormone on clinical outcomes after frozen-thawed embryo transfer.

OBJECTIVE: To evaluate the effects of recombinant human growth hormone (rhGH) on clinical outcomes of frozen-thawed embryo transfer (FET). METHODS: A prospective study was conducted among 240 patients (aged ≤38years) who underwent FET cycles at a center in Hefei, China, between November 2011 and October 2012. Patients were divided into three groups on the basis of visit order: those in group A received hormone-replacement therapy (HRT) for endometrial preparation, those in group B received HRT plus simultaneous rhGH, and those in group C received rhGH on day8 of HRT. RESULTS: Ten cycles were cancelled; 230 FET cycles were analyzed (77 in group A, 77 in group B, 76 in group C). The rates of clinical pregnancy, embryo implantation, and live birth were significantly higher in group B than in group A, as were the serum levels of estradiol and insulin-like growth factor-1 (P≤0.033 for all comparisons). Endometrial thickness and serum levels of vascular endothelial growth factor were significantly higher in group B than in groups A and C, whereas pulsatility index, resistance index, and peak systolic velocity/end diastolic velocity of the uterine arcuate artery were significantly lower (P≤0.017 for all comparisons). CONCLUSION: Simultaneous administration of rhGH with HRT could improve clinical outcomes after FET by increasing endometrial blood perfusion and expression of cytokines related to endometrial receptivity.