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Heterakis gallinarum is one of the common parasitic nematodes found in the caecum of poultry. To investigate the genetic diversity and genetic structure of the H. gallinarum population in Sichuan, we amplified and sequenced the complete mitochondrial (mt) cytochrome c oxidase subunit II (cox2) gene of 59 H. gallinarum isolates from seven different geographical regions, then analyzed their genetic polymorphisms. All cox2 genes of the 59 H. gallinarum isolates were 696 bp in length, with an average A + T content of 67.1%. Fifty-nine sequences contained 34 variable sites, and were classified into 23 haplotypes (HS1-HS23). The values of haplotype diversity (Hd) and nucleotide diversity (π) were 0.688 and 0.00288, respectively. Based on values of FST and Nm (FST = 0.01929, Nm = 12.71), there was a frequent gene flow but no significant genetic differentiation observed among the populations. The network map showed that the most prominent haplotype was HS1, and the other haplotypes (HS2-HS23) were centered on HS1 with a star-like topology, indicating that H. gallinarum had previously experienced a population expansion. To our knowledge, this is the first research on the population genetics of H. gallinarum based on mitochondrial cox2. [ABSTRACT FROM AUTHOR]

Conventional radiotherapy has a good killing effect on femoral echinococcosis. However, the sciatic nerve around the lesion is irreversibly damaged owing to bystander effects. Although intensity-modulated radiation therapy shows great advantages for precise dose distribution into lesions, it is unknown whether intensity-modulated radiation therapy can perfectly protect the surrounding sciatic nerve on the basis of good killing of femoral echinococcosis foci. Therefore, this study comparatively analyzed differences between intensity-modulated radiation therapy and conventional radiotherapy on the basis of safety to peripheral nerves. Pure-breed Meriones meridiani with bilateral femoral echinococcosis were selected as the research object. Intensity-modulated radiation therapy was used to treat left femoral echinococcosis of Meriones meridianus, while conventional radiotherapy was used to treat right femoral echinococcosis of the same Meriones meridianus. The total radiation dose was 40 Gy. To understand whether intensity-modulated radiation therapy and conventional radiotherapy can kill femoral echinococcosis, trypan blue staining was used to detect pathological changes of bone Echinococcus granulosus and protoscolex death after radiotherapy. Additionally, enzyme histochemical staining was utilized to measure acid phosphatase activity in the protoscolex after radiotherapy. One week after radiotherapy, the overall structure of echinococcosis in bilateral femurs of Meriones meridiani treated by intensity-modulated radiation therapy disappeared. There was no significant difference in the mortality rate of protoscoleces of Echinococcus granulosus between the bilateral femurs of Meriones meridiani. Moreover, there was no significant difference in acid phosphatase activity in the protoscolex of Echinococcus granulosus between bilateral femurs. To understand the injury of sciatic nerve surrounding the foci of femoral echinococcosis caused by intensity-modulated radiation therapy and conventional radiotherapy, the ultrastructure of sciatic nerves after radiotherapy was observed by transmission electron microscopy. Additionally, apoptosis of neurons was examined using a terminal-deoxynucleotidyl transferase-mediated dUTP nick end labeling assay, and expression of Bcl-2 and Bax in sciatic nerve tissue was detected by immunohistochemical staining and western blot assay. Our results showed that most neurons in the left sciatic nerve of Meriones meridiani with echinococcosis treated by intensity-modulated radiation therapy had reversible injury, and there was no obvious apoptosis. Compared with conventional radiotherapy, the number of apoptotic cells and Bax expression in sciatic nerve treated by intensity-modulated radiation therapy were significantly decreased, while Bcl-2 expression was significantly increased. Our findings suggest that intensity-modulated radiation therapy has the same therapeutic effect on echinococcosis as conventional radiotherapy, and can reduce apoptosis of the sciatic nerve around foci caused by radiotherapy. Experiments were approved by the Animal Ethics Committee of People's Hospital of Xinjiang Uygur Autonomous Region, China (Approval No. 20130301A41) on March 1, 2013., Competing Interests: None

Heterakis gallinarum is one of the common parasitic nematodes found in the caecum of poultry. To investigate the genetic diversity and genetic structure of the H. gallinarum population in Sichuan, we amplified and sequenced the complete mitochondrial (mt) cytochrome c oxidase subunit II (cox2) gene of 59 H. gallinarum isolates from seven different geographical regions, then analyzed their genetic polymorphisms. All cox2 genes of the 59 H. gallinarum isolates were 696 bp in length, with an average A + T content of 67.1%. Fifty-nine sequences contained 34 variable sites, and were classified into 23 haplotypes (HS1-HS23). The values of haplotype diversity (Hd) and nucleotide diversity (π) were 0.688 and 0.00288, respectively. Based on values of F ST and Nm (F ST  = 0.01929, Nm = 12.71), there was a frequent gene flow but no significant genetic differentiation observed among the populations. The network map showed that the most prominent haplotype was HS1, and the other haplotypes (HS2-HS23) were centered on HS1 with a star-like topology, indicating that H. gallinarum had previously experienced a population expansion. To our knowledge, this is the first research on the population genetics of H. gallinarum based on mitochondrial cox2.