The cis-acting 3''-element of rubella virus RNA has DNA promoter activity.

The gene(NGFB) encoding the β subunit of mature human nerve growth factor (hNGFB) was subcloned into the pJLA503 expression vector under the control of bacteriophage promoters p_R and p_L, and expressed in Escherichia coli. The recombinant protein represented approximately 3% of the total cellular protein. Biologically active hNGFB was solubilized (0.2% total NGFB) and purified by cation-exchange chromatography and it yielded two bands on polyacrylamide-gel electrophoresis under nonreducing conditions, corresponding to the monomeric (14 kDa) and homodimeric (26.5 kDa) forms of the molecule. Both hNGFB forms were immunopositive on Western blots with rabbit anti-NGFB antibodies; however, following additional purification, only the species corresponding to the hNGFB homodimer was biologically active on cultured chicken dorsal root ganglion neurons. These results demonstrate the feasibility of synthesizing the biologically active form of hNGFB in E. coli.     

Ultrastructural localization of the secretory aspartyl proteinase in Candida albicans cell wall in vitro and in experimentally infected rat vagina

Detection and ultrastructural localization of aspartyl proteinase (Sap) in Candida albicans experimentally infecting rat vagina were studied. Two Sap-positive (Sap+) and one Sap-negative (Sap-) strains of the fungus, endowed with high and low experimental vaginopathic potential, respectively, were used. Both Sap+ strains produced consistent Sap levels in the rat vagina, while the Sap- strain did not produce any measurable Sap. Electron microscopy of thin sections of chemically-fixed vaginal scrapings showed clear evidence of hyphae of proteolitic strains of C. albicans invading the keratinized epithelial cell layer of the vagina. The fungal cells exhibited a pronounced fibrillar layer on the cell wall with a marked intermixing of fungal and vaginal materials especially pronunced at the hyphal tip. Post-embedding immunogold techniques with the use of anti-Sap polyclonal and the specifically generated monoclonal antibody GF1 showed that Sap was essentially localized in the cell wall of C. albicans early during infection, in a cytological pattern mirroring Sap localization in C. albicans cells grown in Sap-inductive media in vitro. In summary, the data offer a new biochemical and ultrastructural evidence that Sap is actively secreted during experimental rat vaginitis by C. albicans. Cell wall localization of Sap is probably inherent to this active secretion process. This revised version was published online in August 2006 with corrections to the Cover Date.     

Occupational risk factors for hip osteoarthritis are associated with early hip structural abnormalities: a 3.0?T magnetic resonance imaging study of community-based adults

IntroductionOccupational exposure to heavy lifting and stair climbing are associated with radiographic hip osteoarthritis (OA). This study examined whether these activities are associated with early structural hip joint changes in a community-based population.MethodsIn total, 198 community-based people with no history of hip disease, including OA, had 3.0 T-magnetic resonance imaging (MRI) to assess hip cartilage volume, defects and bone marrow lesions (BMLs). Recall of occupational exposure to heavy lifting and stair climbing aged 18 to 30 years and in the previous 10 years were collected. A persistence score was defined as exposure at neither time point (0), at one time point (1) or at both time points (2).ResultsExposure to heavy lifting when aged 18 to 30 years was associated with BMLs of the central superolateral femoroacetabular region (odds ratio (OR) 3.9, 95% confidence interval (CI) 1.6 to 9.8, P <0.01), with persistence score associated with cartilage defects in the central superolateral region of the femoral head (OR 1.6, 95% CI 1.0 to 2.5, P = 0.04). Exposure to stair climbing aged 18 to 30 years and persistence score were associated with an increased risk of cartilage defects in the central superolateral femoral head and BMLs in the central superolateral and posterior femoroacetabular regions (OR range 2.1 to 3.2, all P ≤0.03).ConclusionsOccupational exposure to heavy lifting and stair climbing are associated with hip structural abnormalities. If confirmed by longitudinal data, such associations may explain how occupational activities affect the hip joint and may identify new targets for the prevention of hip OA.     

Role of Probiotics in Pediatric Patients with Helicobacter pylori Infection: A Comprehensive Review of the Literature

Background: The current guidelines suggest the use of triple therapy as first choice treatment of Helicobacter pylori infection, although the eradication failure rate is more than 30%. Current interest in probiotics as therapeutic agents against H. pylori is stimulated not only by the clinical data showing efficacy of some probiotics in different gastrointestinal diseases but also by the increasing resistance of pathogenic bacteria to antibiotics, thus the interest for alternative therapies is a real actual topic. Aim: To review in vitro and in vivo studies on the role of probiotics in H. pylori infection focusing on the paediatric literature. Materials and methods: Pre‐clinical and clinical paediatric studies in English assessing the role of probiotics in H. pylori infection identified by MEDLINE search (1950–2009) were reviewed. Results: In vitro studies demonstrated an inhibitory activity of probiotics on H. pylori growth and that this effect is extremely strain specific. Available data in children indicate that probiotics seems to be efficacious for the prevention of antibiotic associated side‐effects, and might be of help for the prevention of H. pylori complications by decreasing H. pylori density and gastritis, and for the prevention of H. pylori colonization or re‐infection by inhibiting adhesion to gastric epithelial cells. There is no clear evidence that probiotics may increase the H. pylori eradication rate. Conclusion: Both in vitro and in vivo studies provide evidence that probiotics may represent a novel approach to the management of H. pylori infection.     

5S ribosomal RNA genes in six species of Mediterranean grey mullets: genomic organization and phylogenetic inference.

This paper describes a study of the 5S ribosomal RNA genes (5S rDNA) in a group of 6 species belonging to 4 genera of Mugilidae. In these 6 species, the relatively short 5S rDNA repeat units, generated by PCR and ranging in size from 219 to 257 bp, show a high level of intragenomic homogeneity of both coding and spacer regions (NTS-I). Phylogenetic reconstructions based on this data set highlight the greater phylogenetic and genetic diversity of Mugil cephalus and Oedalechilus labeo compared with the genera Liza and Chelon. Comparative sequence analysis revealed significant conservation of the short 5S rDNA repeat units across Chelon and Liza. Moreover, a second size class of 5S rDNA repeat units, ranging from roughly 800 to 1100 bp, was produced in the Liza and Chelon samples. Only short 5S rDNA repeat units were found in M. cephalus and O. labeo. The sequences of the long 5S rDNA repeat units, obtained in Chelon labrosus and Liza ramada, differ owing to the presence of 2 large insertion/deletions (indels) in the spacers (NTS-II) and show considerable sequence identity with NTS-I spacers. Interspecific sequence variation of NTS-II spacers, excluding the indels, is low. Southern-blot hybridization patterns suggest an intermixed arrangement of short and long repeat units within a single chromosome locus.     

Difference in reproductive mode rather than ploidy explains niche differentiation in sympatric sexual and apomictic populations of Potentilla puberula

Apomicts tend to have larger geographical distributional ranges and to occur in ecologically more extreme environments than their sexual progenitors. However, the expression of apomixis is typically linked to polyploidy. Thus, it is a priori not clear whether intrinsic effects related to the change in the reproductive mode or rather in the ploidy drive ecological differentiation. We used sympatric sexual and apomictic populations of Potentilla puberula to test for ecological differentiation. To distinguish the effects of reproductive mode and ploidy on the ecology of cytotypes, we compared the niches (a) of sexuals (tetraploids) and autopolyploid apomicts (penta‐, hepta‐, and octoploids) and (b) of the three apomictic cytotypes. We based comparisons on a ploidy screen of 238 populations along a latitudinal transect through the Eastern European Alps and associated bioclimatic, and soil and topographic data. Sexual tetraploids preferred primary habitats at drier, steeper, more south‐oriented slopes, while apomicts mostly occurred in human‐made habitats with higher water availability. Contrariwise, we found no or only marginal ecological differentiation among the apomictic higher ploids. Based on the pronounced ecological differences found between sexuals and apomicts, in addition to the lack of niche differentiation among cytotypes of the same reproductive mode, we conclude that reproductive mode rather than ploidy is the main driver of the observed differences. Moreover, we compared our system with others from the literature, to stress the importance of identifying alternative confounding effects (such as hybrid origin). Finally, we underline the relevance of studying ecological parthenogenesis in sympatry, to minimize the effects of differential migration abilities.     

MRE11-RAD50-NBS1 Complex Is Sufficient to Promote Transcription by RNA Polymerase II at Double-Strand Breaks by Melting DNA Ends

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