The pathogenesis of bacterial keratitis: studies with Pseudomonas aeruginosa

Bacterial keratitis is a sight‐threatening corneal disease that is most commonly associated with the extended wear of soft contact lenses. Over the past decade, we have investigated the pathogenesis of infectious keratitis involving the opportunistic pathogen Pseudomonas aeruginosa. Our research has focused on understanding the respective roles of bacteria and host in the establishment of this infection. Here, we provide a current perspective on P. aeruginosa keratitis, reviewing some of the research developments that have helped shape our views on the mechanisms by which pathogen and host response cause corneal disease. P. aeruginosa may provide a model for the pathogenesis of bacterial keratitis and help further elucidate the complex array of host factors that normally protect the cornea from infectious agents.     

Atypical pityriasis rosea and Hodgkin's disease.

Pityriasis rosea (PR)-like eruptions have been associated with several neoplasms and drugs. These eruptions may be atypical. To date, the association of Hodgkin's disease with PR-like eruptions has rarely been reported. We report a 37-year-old patient with clinical lesions of PR-like, systemic symptoms and lymphadenopathies, who was subsequently diagnosed with Hodgkin's disease.     

Sequence analysis, identification of evolutionary conserved motifs and expression analysis of murine tcof1 provide further evidence for a potential function for the gene and its human homologue, TCOF1

The gene mutated in Treacher Collins syndrome, an autosomal dominant disorder of facial development, has recently been cloned. While the function of the predicted protein, Treacle, is unknown, it has been shown to share a number of features with the highly phosphorylated nucleolar phosphoproteins, which play a role in nucleolar-cytoplasmic transport. In the current study, the murine homologue of the Treacher Collins syndrome gene has been isolated and shown to encode a low complexity, serine/alanine-rich protein of 133 kDa. Interspecies comparison indicates that the proteins display 61.5% identity, with the level of conservation being greatest in the regions of acidic/basic amino acid repeats and nuclear localization signals. These features are shared with the nucleolar phosphoproteins. Confirmation that the gene isolated in the current study is orthologous with the Treacher Collins syndrome gene was provided by the demonstration that it mapped to central mouse chromosome 18 in a conserved syntenic region with human chromosome 5q21-q33. Expression analysis in the mouse indicated that the gene was expressed in a wide variety of embryonic and adult tissues. Peak levels of expression in the developing embryo were observed at the edges of the neural folds immediately prior to fusion, and also in the developing branchial arches at the times of critical morphogenetic events. These observations support a role for the gene in the development of the craniofacial complex and provide further evidence that the gene encodes a protein which may be involved in nucleolar-cytoplasmic transport.