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Objective: To investigate the killing effect of hypericin on tachyzoites of Toxoplasma gondii RH strain in vitro., Methods: Normal saline （group A） and different concentrations of hypericin (5 μg/ml, group B; 50 μg/ml, group C; 500 μg/ml, group D） were added to T. gondii tachyzoites in 24-well plate（1×10(6)/well）. The tachyzoites were harvested after 2, 4 and 6 h, and underwent the following treatment: trypan blue staining to calculate the dyeing rate, Giemsa staining to observe the morphological and structural alterations of tachyzoites, and transmission electron microscopy to observe the ultrastructure of tachyzoites. In addition, flow cytometry was performed to calculate the survival rate of YFP-carrying Toxoplasma with the same treatment., Results: The trypan blue dyeing rate at 2 h after treatment in groups B, C and D was（11.0±3.6）%, （25.0±6.3）% and（40.0±2.7）% respectively, with a significant difference of group D versus B and C （P<0.01）, and groups C and D versus group A ［（6.0±3.0）%）］. The dyeing rate at 4 h and 6 h in group D was（97.0±2.0）% and （98.0±1.7）%, respectively, both significantly higher than that of groups C ［（30.0±7.2）%, （42.7±5.5）%］, B ［（20.0±3.0）%, （34.0±6.6）%］ and A ［（10.0±1.0）%, （19.3±4.9）%］（P<0.01）. Giemsa staining showed gradual end swelling and necrosis of tachyzoites with increased treatment duration and dosage. Transmission electron microscopy showed swelling of worm body, gap between cell membrane and matrix, increase and enlargement of vacuoles inside worm body, disruption of cell membrane, and dissolving of inner structures, with increased treatment duration. Flow cytometry showed significant difference of tachyzoite survival rate at 2, 4 and 6 h after hypericin treatment with that of the control group（P<0.01）. The survival rate of group C at 2 h after hypericin treatment was（7.9±1.9）%, significantly lower than that of groups B ［（38.1±5.5）%］ and A ［（81.8±6.0）%］ （P<0.01）. No tachyzoite was found to survive in group D at 2 h and in group C at 4 h. The survival rate of group B at 4 and 6 h after hypericin treatment was（14.3±7.9）% and （1.4±1.8）%, respectively, both significantly lower than that of group A［（73.8±11.3）% and（64.1±14.4）%, respectively］ （P<0.01）., Conclusion: Hypericin has a remarkable killing effect on T. gondii tachyzoites, and the efficacy positively correlates with the dose and treatment duration.

Objective: To clone a gametocyte specific protein Pfgdv1 of Plasmodium falciparum, express and identify recombinant Pfgdvl protein in vitro., Methods: PCR was performed to amplify Pfgdv1 from P. falciparum DNA which was got from the patient who was infected with P. falciparum, and the PCR product was inserted into pET28a (+) vector. pET28a-Pfgdv1 recombinant plasmid was constructed and transformed into E. coli host BL21 (DE3+). IPTG was used to induce the recombinant Pfgdv1 protein fused with His tag, and the protein was purified by His-NTA affinity chromatography. The recombinant protein was identified by SDS-PAGE and Western blotting., Results: The PCR product of Pfgdv1 gene was about 1.65 kb, meeting the expectation of predicted fragment size. The recombinant protein was about 67 kDa, which could be recognized by His-Tag monoclonal antibody., Conclusion: The Pfgdv1 gene of P. falciparum is successfully cloned, and the recombinant Pfgdv1 protein is expressed, thereby providing an opportunity for further study on transmission blocking vaccine.

Malaria remains a serious public health problem, especially in developing countries. With the deepening of the understanding of vivax malaria, Plasmodium vivax is also attracting more and more attention. An effective drug treatment is the foundation of controlling or even eliminating malaria. In recent years, more and more reports of chloroquine-resistance Plasmodium vivax have been reported. Plasmodium vivax chloroquine resistance has been a focus problem in vivax malaria prevention and treatment. In this paper, the research progress on distribution situation, detection methods and molecular markers of Plasmodium vivax chloroquine resistance is summarized.

Objective: To construct recombinant Mycobacterium smegmatis vaccine expressing Cysticercus cellulosae cC1 antigen., Methods: The recombinant pET28a-cC1 plasmid was extracted and double digested by Xho I and BamH I restriction enzymes, and shuttle plasmid pMV261 was extracted and double digested by Hind III and BamH I restriction enzymes. Both fragments were modified by Klenow fragment to form blunt end, then the large fragments of cC1 and pMV261 plasmid were purified and ligated by T4 ligase enzyme. The recombinant pMV261-cC1 plasmid was constructed and sequenced. Then the pMV261-cC1 plasmid was transformed into Mycobacterium smegmatis by the electrotransformation method. The recombinant cC1-Mycobacterium smegmatis was induced by heat and identified by the Western blotting method with the sera of cysticercosis patients. In addition, the growth states of the Mycobacterium smegmatis and the recombinant cC1-Mycobacterium smegmatis were compared and the growth curves were drawn., Results: The restriction enzyme and sequencing results showed that the recombinant pMV261-cC1 plasmid was successfully constructed. After heat induction, a 40 kD band was showed by PAGE analysis of cC1-Mycobacterium smegmatis. The Western blotting results showed that the sera of cysticercosis patients could recognize the 40 kDa band, which suggested that cC1 protein was expressed in Mycobacterium smegmatis. Compared with the Mycobacterium smegmatis, the recombi- nant cC1-Mycobacterium smegmatis showed no significant difference in proliferation characteristics., Conclusion: The recombinant cC1-Mycobacterium smegmatis vaccine has been successfully constructed.

Objective: To investigate the efficacy of heparin gelatin sponge stickers in the treatment of traumatic perforation of tympanic membrane., Methods: Total of 79 cases (83 ears) of traumatic perforation of tympanic membrane were randomly divided into two groups: the test group had 54 patients (58 ears), and the control group had 25 cases (25 ears). The test group received the treatment of heparin gelatin sponge stickers, and the control group received conservative traditional drying method. All the subjects were followed up for 4 weeks, observed and recorded the rate and healing period of traumatic tympanic membrane., Results: In 4-week's follow-up, 56 ears were cured in the test group, with a rate of 96.55%. Fourteen ears were cured in the control group with a rate of 56.00%. The healing rate of test group was significantly higher than that of the control group (χ(2) = 18.79, P < 0.01). The average of healing period was 17.6 days in the test group, and 32.0 days in the control group. There were significant differences in healing period between two groups (t = 6.37, P < 0.01). All the cured tympanic membrane in the test group was morphologically complete. In all followed up patients, there were no allergies and signs of infection, as well as other adverse reaction in the process of healing., Conclusion: The heparin gelatin sponge can effectively enhance closure of the traumatic perforation of tympanic membrane and can shorten the healing period of traumatic perforation of tympanic membrane, and the smaller of the perforation, the shorter of healing period.