Methods A 20-year-old man, who complained about occipitocervical

Methods. A 20-year-old man, who complained about occipitocervical pain and cervical activities limitation, and presented with a 3-month history of weakness and numbness of all 4 limbs after sustaining a minor head trauma. Computed tomography scan showed anterior arch midline defect, posterior arch midline

aplasia. Steel plate fixation by transoral approach was performed to repair bipartite atlas deformity.

Results. In 1-month follow-up, occipitocervical pain disappeared. The patient had significant improvement over next 3 months. In 6-month follow-up, we observed bony union of anterior arch of atlas without abnormal manifestations. EVP4593 The postoperative rotation in the atlanto-axial joint was returned to normal. The patient had no symptoms of postoperative instability of C1-C2.

Conclusion. We described a rare association of an anterior arch midline defect, posterior arch midline aplasia. The natural history of patients with bipartite atlas deformity suggests that these people have a potentially precarious existence. Transoral osteosynthesis of the anterior ring and the lateral masses of C1 is a new technique that allows maintenance of rotatory mobility in the C1-C2 joint and restoration PXD101 concentration of congruency

in the atlanto-occipital and atlantoaxial joints.”
“Wolbachia are bacteria that live inside the cells of a large number of invertebrate hosts and are transmitted from infected females to their offspring. Their presence is associated with cytoplasmic incompatibility in several species of Drosophila. Cytoplasmic incompatibility results when the sperm

of infected males fertilize eggs of uninfected females, causing more or less intense embryonic mortality (unidirectional incompatibility). This phenomenon also appears in crosses between populations infected with different Wolbachia strains (bidirectional incompatibility). The influence of Wolbachia infection on host populations has attracted attention as a potentially rapid mechanism for development of reproductive isolation and subsequent speciation. We examined the influence of this bacterium on reproductive isolation in interspecific crosses between Drosophila melanogaster selleck products and D. simulans. We found that Wolbachia infection negatively affected these two species in homospecific crosses. However, in interspecific crosses, it only influenced sexual isolation, as infected females more frequently hybridized than females free of infection; postzygotic reduction of fitness (bidirectional cytoplasmic incompatibility) was not detected. This would be explained by the existence of several modes of rescue systems in these two species, reducing cytoplasmic incompatibility between them. Wolbachia does not appear to cause reproductive isolation between these two species.

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