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To determine the role of gastrointestinal carriage in Klebsiella pneumoniae liver abscess, we studied 43 patients. Bacterial isolates from liver and fecal samples from 10 patients with this condition and 7 healthy carriers showed identical serotypes and genotypes with the same virulence. This finding indicated that gastrointestinal carriage is a predisposing factor for liver abscess. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To examine the roles of STATs 1 and 3 in CCL2 production in human osteoblastic cells and their influences on arthritis development. METHODS: The expression of CCL2 in primary human osteoblasts and U2OS human osteoblastic cells was examined by Northern blotting and enzyme-linked immunosorbent assay. The roles of STAT-1/3 and c-Fos were assessed using short hairpin RNAs (shRNA) to silence their functions. Serine phosphorylation of STATs was assessed by Western blotting. Promoter activities of c-Fos and CCL2 were assessed by chloramphenicol acetyltransferase and luciferase assays, respectively. Interactions of STAT-1, STAT-3, and c-Fos with DNA were evaluated by electrophoretic mobility shift assay (EMSA) and immunoprecipitation. The effect of the JAK inhibitor AG-490 on collagen-induced arthritis (CIA) in rats was examined using immunohistochemistry. RESULTS: Oncostatin M (OSM) stimulated CCL2 expression in primary human osteoblasts and U2OS cells. In U2OS cells, STAT-1 and STAT-3 were involved in OSM-stimulated CCL2 expression, and both the phosphatidylinositol 3-kinase/Akt and MEK/ERK pathways were implicated in the activation of these STATs. STAT-1 and STAT-3 modulated the expression of c-Fos and directly transactivated the CCL2 promoter. Moreover, EMSA showed formation of a DNA-protein complex containing STAT-1, STAT-3, and interestingly, c-Fos. Immunoprecipitation confirmed the binding between c-Fos and STAT-1/3. Reporter assay revealed synergistic attenuation of CCL2 promoter activity by shRNA targeting of STAT-1, STAT-3, and c-Fos. AG-490 suppressed OSM-stimulated activation of STAT-1/3 and synthesis of CCL2 in vitro and diminished the severity of CIA and the number of CCL2-synthesizing osteoblasts in vivo. CONCLUSION: These findings show that multiple levels of STAT-1/3 signaling modulate OSM-stimulated CCL2 expression in human osteoblastic cells. Clinically, this pathway may be related to the pathogenesis of arthritis. [ABSTRACT FROM AUTHOR]

Background. Previously, we reported that there was an outbreak of human immunodeficiency virus type 1 (HIV-1) circulating recombinant form (CRF) 07_BC among injection drug users (IDUs) in Taiwan in 2004. The objectives of the present study were to conduct a molecular epidemiological analysis and to characterize the full-length genome of the Taiwanese CRF07_BC.Methods. Three hundred and fifty-eight patients with HIV-1/AIDS from hospitals and 133 HIV-1-infected inmates from detention centers were recruited. DNA sequencing and phylogenetic analysis were conducted to determine subtypes and evolutionary relationships. Recombination breakpoints of 2 full-length CRF07_BC strains were elucidated using a bootscanning method.Results. Of 206 HIV-1-infected patients who received a diagnosis in 2004, 44.7% were infected with subtype B, 53.4% with CRF07_BC, and 1.5% with CRF01_AE. Ninety-eight percent (109/111) of IDUs were infected with CRF07_BC. Deletions of 7-11 amino acids in both p6(gag) and p6(pol) proteins were noted among the Taiwanese CRF07_BC strains. The CRF_07BC strains belonged to 2 phylogenetic clusters, and the first cluster contained only CRF07_BC strains from the southern part of Taiwan.Conclusions. The Taiwanese CRF07_BC strains had 97% full-length sequence homology with the prototype from mainland China. CRF07_BC was first introduced into the southern region in 2002 and then spread to other regions in Taiwan in 2004. Copyright © 2007 Infectious Diseases Society of America [ABSTRACT FROM AUTHOR]