[Correlation between genetic differences of mates and pathogenicity of Schistosoma japonicum in definitive host].

OBJECTIVE: To explore the correlation between the genetic dissimilarity and heterozygosity of mates and the pathogenicity of Schistosoma japonicum in the definitive host. METHODS: By using seven microsatellite loci markers, S. japonicum genotyping of sixteen pairs randomly mated was performed, the genetic dissimilarity and heterozygosity were calculated between the mates, and the correlation between the genetic dissimilarity and heterozygosity of the mates and the pathogenicity of S. japonicum in the definitive host was evaluated. RESULTS: There was a significant correlation between the genetic similarity of S. japonicum mates and the mean number of eggs per worm pair in the liver and intestinal tissue (r = 0.501 6, P < 0.05; r = 0.796 5, P < 0.01, respectively) and the hatching rate of deposited eggs in the liver (r = 0.508 3, P < 0.05), respectively. There was no correlation between the genetic similarity of the mates and hepatosplenomegaly per worm pair (r = 0.109 5, P > 0.05; r = 0.265 3, P > 0.05, respectively) and the average diameter of granuloma in the liver (r = -0.272 7, P > 0.05), respectively. There was no correlation between the heterozygosity of the mates and all the pathological parameters of S. japonicum in the definitive host (P > 0.05). CONCLUSIONS: There is the correlation between the genetic dissimilarity of the mates and the pathogenicity of S. japonicum in the definitive host, and the genetic dissimilarity is greater, pathogenicity is weaker. There is no correlation between heterozygosity of the mates and the pathogenicity of S. japonicum in the definitive host.

Co-infections with Babesia microti and Plasmodium parasites along the China-Myanmar border.

BACKGROUND: Babesiosis is an emerging health risk in several parts of the world. However, little is known about the prevalence of Babesia in malaria-endemic countries. The area along the China-Myanmar border in Yunnan is a main endemic area of malaria in P.R. China, however, human infection with Babesia microti (B. microti) is not recognized in this region, and its profile of co-infection is not yet clear. METHODS: To understand its profile of co-infections with B. microti, our investigation was undertaken in the malaria-endemic area along the China-Myanmar border in Yunnan between April 2012 and June 2013. Four parasite species, including B. microti, Plasmodium falciparum (P. falciparum), P. vivax, and P. malariae, were identified among 449 suspected febrile persons detected by nested polymerase chain reaction (PCR) assay based on small subunit ribosomal ribonucleic acid (RNA) genes of B. microti and Plasmodium spp. RESULTS: Of all the collected samples from febrile patients, mono-infection with B. microti, P. vivax, P. falciparum, and P. malariae accounted for 1.8% (8/449), 9.8% (44/449), 2.9% (13/449), and 0.2% (1/449), respectively. The rate of mixed infections of B. microti with P. falciparum or P. vivax are both 0.2% (1/449), and mixed infections of P. falciparum and P. vivax accounted for 1.1% (5/449). CONCLUSIONS: This report supports the hypothesis that babesiosis caused by B. microti is emerging along the China-Myanmar border in the Yunnan province, P.R. China, but it was ignored because of low parasitemia or mixed infection with Plasmodium spp. More sensitive and specific diagnosis methods are needed to find the rapid response mechanism of emergency for babesiosis and malaria co-prevalence areas.

[Study on expression of Treg cells in attenuated Schistosoma japonicum cercariae immunized BALB/c mice].

OBJECTIVE: To study the expression differences of CD4+CD25+Foxp3+Treg cells between the attenuated cercariae immunized mice and the normal infected mice and discuss the immune protection mechanisms of the mice immunized with attenuated cercariae. METHODS: Forty female BALB/c mice were divided into 2 groups, group A, the attenuated cercariae immunized group (16 mices) and the group B, the normal cercariae infected group (16 mices), and the last 8 ones served as the blank control. The spleen cells and the ratios of PBMC's CD4+CD25+Foxp3+/CD4+CD25+T cells were compared between the attenuated cercariae immunized mice and normal mice injected by FCM and the Foxp3 expression levels in spleens and livers were assayed by IHC. The transcription factor Foxp3 in the peripheral blood was detected by RT-PCR. RESULTS: In group A and group B, CD4+CD25+Foxp3+/ CD4+CD25+T ratios in the PBMC 6 weeks post-infection were (14.15 +/- 2.62)% and (7.92 +/- 2.22)%, respectively (P < 0.05); the ratios in the spleen cells were (14.52 +/- 2.98)% and (8.18 +/- 2.84)%, respectively (P < 0.05); 8 weeks post-infection, the ratios in the PBMC were (15.92 +/- 2.98)% and (13.26 +/- 2.64)%, respectively, (P < 0.05); the ratios of the spleen cells were (16.42 +/- 2.46)% and (13.48 +/- 2.36)%, respectively (P < 0.05); 6 weeks post-infection, the Foxp3 expression levels in livers were "+" and "-", respectively, and those in the spleens were "++" and "+", respectively; 8 weeks post-infection, the Foxp3 expression levels in the livers were "++" and "-" respectively, and those in the spleens were "++" and "+", respectively. CONCLUSIONS: The expression level of attenuated cercariae immunized group's CD4+CD25+Foxp3+Treg cells is higher than that in the control group during the late stages, suggesting that CD4+CD25+Foxp3+Treg in the attenuated cercariae immunized mice may play one of the important roles in its immune protection mechanisms.

Advances in the research of lipoxygenase inhibitors / 中南大学学报(医学版)

Lipoxygenase is a protein with non-heme iron atom, which has been discovered in many animals and plants. Lipoxygenase which has a close relationship with human tumors, inflammatory diseases, asthma, arteriosclerosis, and toxic action of chemicals could not only di-oxygenate endogenous polyunsaturated fatty acid to yield bioactive factors such as leukotrienes(LTs), but also has co-oxidation activity to activate xenobiotics. Lipoxygenase inhibitors include hydroxamic acid derivatives, nordihydroguaiaretic acid, flavonoids, FLAP inhibitors and so on. All of them can effectively restrain the catalytic action of lipoxygenase. Literatures demonstrate that the inhibitors can block the formation of relevant bioactive factors and toxic products of xenobiotics clinically which are used to prevent and cure the relevant diseases to keep people healthy.