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Klebsiella pneumoniae community-acquired pyogenic liver abscess (PLA) is an emerging infectious disease. The rmpA gene (for regulator of mucoid phenotype A) has been reported to be associated with PLA in prevalence studies. NTUH-K2044, a K1 PLA isolate, carries three rmpA/A2 genes: two large-plasmid-carried genes (p-rmpA and p-rmpA2) and one chromosomal gene (c-rmpA). In this study, we re-examined the role of rmpA/A2 in PLA pathogenesis to clarify the relationship of rmpA/A2 and capsular serotype to virulence. Using isogenic gene deletion strains and complemented strains of NTUH-K2044, we demonstrated that only p-rmpA enhanced expression of capsular polysaccharide synthesis (cps) genes and capsule production. Nevertheless, the lethal dose and in vivo competitive index indicated that p-rmpA does not promote virulence in mice. The prevalence of these three rmpA/A2 and capsular types in 206 strains was investigated. This revealed a correlation of rmpA/A2 with six PLA-related capsular types (K1, K2, K5, K54, K57 and KN1). However, the correlation of rmpA/A2 with K1 strains from the West was less obvious than with the strains from Asia (17/22 vs 39/39, P = 0.0019). Among the three rmpA/A2 genes, p-rmpA was the most prevalent. Due to the strong correlation with PLA-related capsular types, p-rmpA could serve as a surrogate marker for PLA. We found an association of p-rmpA with three widely spaced loci in a large plasmid (30/32). Therefore, rmpA could be co-inherited together with virulence genes carried by this plasmid.

Klebsiella pneumoniae liver abscess with metastatic complications is an emerging infectious disease in Taiwan. To identify genes associated with liver infection, we used a DNA microarray to compare the transcriptional profiles of three strains causing liver abscess and three strains not associated with liver infection. There were 13 clones that showed higher RNA expression levels in the three liver infection strains, and 3 of these 13 clones contained a region that was absent in MGH 78578. Sequencing of the clones revealed the replacement of 149 bp of MGH 78578 with a 21,745-bp fragment in a liver infection strain, NTUH-K2044. This 21,745-bp fragment contained 19 open reading frames, 14 of which were proven to be associated with allantoin metabolism. The K2044 (⌬allS) mutant showed a significant decrease of virulence in intragastric inoculation of BALB/c mice, and the prevalence of this chromosomal region was significantly higher in strains associated with liver abscess than in those that were not (19 or 32 versus 2 of 94; P ‫؍‬ 0.0001 [ 2 test]). Therefore, the 22-kb region may play a role in K. pneumoniae liver infection and serve as a marker for rapid identification.

Hepatitis C virus (HCV) core protein, a component of viral nucleocapsid, has been shown to modulate cellular and viral promoter activities. To identify potential cellular targets for HCV core protein, a human liver cDNA library was screened for core-interacting proteins using the yeast two-hybrid system. Among the proteins identified was heterogeneous nuclear ribonucleoprotein K (hnRNP K), which has been demonstrated to be a transcriptional regulator. The interaction of HCV core protein with hnRNP K was confirmed by glutathione Stransferase fusion protein binding assay, proteinprotein blotting assay, and coimmunoprecipitation in vitro and in vivo. Additionally, these two proteins were shown to be partially colocalized in the nucleus. The hnRNP K-binding site in HCV core protein was mapped to the region from amino acid residues 25-91, a hydrophilic area near the N terminus. The HCV core proteinbinding domain was located within amino acid residues 250 to 392, which contain the three proline-rich domains, of hnRNP K. Furthermore, HCV core protein relieved the suppression effect of hnRNP K on the activity of the human thymidine kinase gene promoter. The specific binding of HCV core protein to hnRNP K suggests that multiple functions of hnRNP K may be disrupted by the core protein during HCV infection and thus explains, in part, the pathogenesis of HCV.

A complex array of factors influences the implementation of inclusion within educational systems. This article examines decision making regarding young children's participation in inclusive programs. A qualitative design was employed to study influential factors over the course of a 5-year period as children moved from inclusive preschool placements to elementary school. Family, classroom, school, and societal influences were examined through families' perspectives on children's school experiences. At the end of the 5-year follow-along period, 60% of the children remained in some level of inclusive placement. Placements were influenced by professionals' decisions and school options, families' abilities to access information, advocates, the match between family needs and expectations and school options, and the influence of specific child and family characteristics. Downloaded fromI t's really imperative to me that he's in a regular classroom because he learns so much that you're not aware of him learning . . . I don't want to shortchange him. (Mother of Lester, a kindergartner diagnosed with autism) I think we have to try [inclusion]. If it doesn't work . . . then we can always make a change. (Mother of Ella, a first grader with Down syndrome) If he were in a regular classroom, he wouldn't get as much attention as he does now. (Mother of Lenny, a second grader with physical disabilities)These quotations from parents hint at the many factors that influence educational placement decisions for children with disabilities in the early school years. Though the provision of educational services in least restrictive or inclusive environments has been a central goal in recent decades, the decision to place a child in an inclusive or self-contained special education program is seldom a clear cut decision. Rather, these decisions reflect a complex transactional process involving multiple factors that often interact and may change over time. Educational placements and the goals and decisions surrounding placements, thus, are not static phenomena.Inclusion in the early years has been the target of many educational initiatives (Buysse, Inclusion is a complex process influenced by many factors within families, classrooms, communities, and society. An individual child's experience both affects and is affected by her or his family beliefs and values, aspects of the classroom (e.g., curricular activities, teacher's philosophy) and school (e.g., services offered, philosophy), as well as the policies and values espoused in the larger community.Children's placement decisions are rarely made on the basis of a single factor. The nature of decision making with respect to inclusion highlights the complexity of these decisions. Often professionals and parents must weigh a variety of factors in this process. Bailey, McWilliam, Buysse, and Wesley (1998) identified potentially competing factors families must weigh as they consider various educational alternatives; these factors included program quality, availability of specialized services t...

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SummaryMost viroids replicate in the nuclei of infected plant cells. Nuclear import of the incoming RNA thus represents a key control point for establishment of a systemic infection. However, little is known about the mechanisms by which viroids are transported into the nucleus. We have characterized nuclear import of infectious, fluorescein-labeled potato spindle tuber viroid (F-PSTVd) in permeabilized tobacco BY2 cells. Import was observed for F-PSTVd but not for mRNA fragments of the same size or two viroids believed to replicate in the chloroplasts. Import of F-PSTVd was inhibited by addition of a 10-fold excess of nonfluorescent PSTVd but not by similar amounts of control RNAs. Import was not inhibited by pre-incubation with GTP-γ-S or GDP-β-S, however. Disruption of microtubules and actin filaments with oryzalin or cytochalasin D did not inhibit F-PSTVd import. Taken together, our results indicate that (i) PSTVd possesses a sequence and/or structural motif for nuclear import and (ii) the import is a cytoskeleton-independent process that is mediated by a specific and saturable receptor. Insensitivity to GTP-γ-S and GDP-β-S treatment suggests that PSTVd import is not coupled to Ran GTPase cycle, which mediates nuclear transport of many proteins and nucleic acids. To our knowledge, our studies are the first to examine the mechanisms of nuclear transport of RNA in plants.