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C Strains (c + strain)
Selected AbstractsRelations between open-field, elevated plus-maze, and emergence tests in C57BL/6J and BALB/c mice injected with GABA- and 5HT-anxiolytic agentsFUNDAMENTAL & CLINICAL PHARMACOLOGY, Issue 3 2010Robert Lalonde Abstract Two 5HT1A receptor agonists and chlordiazepoxide were examined in open-field, elevated plus maze, and emergence tests. At doses with no effect in the open-field, chlordiazepoxide increased open and open/total arm visits as well as open arm duration in the elevated plus maze, whereas 5HT1A receptor agonists showed an anxiolytic response on a single measure. The anxiolytic action of chlordiazepoxide was limited to the less active BALB/c strain. Unlike the 5HT1A receptor agonists, chlordiazepoxide was also anxiolytic in the emergence test, once again only in BALB/c and not C57BL/6J mice. Significant correlations were found between emergence latencies and specific indicators of anxiety in the elevated plus-maze in chlordiazepoxide-treated but not in mice treated with buspirone and 8-OH-DPAT. These results indicate that elevated plus-maze and emergence tests depend on benzodiazepine receptors. In contrast, 5HT1A receptor agonists were ineffective in the emergence test and no correlation was found between emergence latencies and specific indicators of anxiety in the elevated plus-maze. Though superficially similar, the emergence test seems to tap into a partially separate facet of anxiety. [source] Worldwide distribution of Pseudomonas aeruginosa clone C strains in the aquatic environment and cystic fibrosis patientsENVIRONMENTAL MICROBIOLOGY, Issue 7 2005Ute Römling Summary Highly successful bacterial clones have the ability to effectively colonize environmental niches and patients. However, the factors which determine the complex interplay between the colonization of environmental niches and patients are mainly unknown. In this study we show that Pseudomonas aeruginosa clone C strains are distributed worldwide and highly prone to infect cystic fibrosis (CF) patients in Canada, England, France and Germany. In Hanover, Germany and Vancouver, Canada, clone C strains are highly prevalent in the CF patient community, although the mechanisms of acquisition may have been different. All clone C strains showed highly related macrorestriction fragment pattern of the whole genome as visualized by pulsed-field gel electrophoresis and harboured the 102 kbp plasmid pKLC102. Comparison of three prevalent P. aeruginosa clones with different distribution between the environment and patients revealed that neither enhanced biofilm formation nor antibiotic resistance was responsible for the spread of clone C. Clone M, which was highly prevalent in the clinical environment such as sanitary facilities, lacked motility, which could explain its relatively low prevalence in CF patients. Elucidation of the mechanisms which lead to the prevalence of clone C strain in patients and the environment requires the investigation of additional phenotypes. [source] Bordetella pertussis fimbriae are effective carrier proteins in Neisseria meningitidis serogroup C conjugate vaccinesFEMS IMMUNOLOGY & MEDICAL MICROBIOLOGY, Issue 2 2001Karen M Reddin Abstract Serogroup C meningococcal conjugate vaccines generally use diphtheria or tetanus toxoids as the protein carriers. The use of alternative carrier proteins may allow multivalent conjugate vaccines to be formulated into a single injection and circumvent potential problems of immune suppression in primed individuals. Bordetella pertussis fimbriae were assessed as carrier proteins for Neisseria meningitidis serogroup C polysaccharide. Fimbriae were conjugated to the polysaccharide using modifications of published methods and characterised by size exclusion chromatography; co-elution of protein and polysaccharide moieties confirmed conjugation. The conjugates elicited boostable IgG responses to fimbriae and serogroup C polysaccharide in mice, and IgG:IgM ratios indicated that the responses were thymus-dependent. High bactericidal antibody titres against a serogroup C strain of N. meningitidis were also observed. In a mouse infection model, the conjugate vaccine protected against lethal infection with N. meningitidis. Therefore, B. pertussis fimbriae are effective carrier proteins for meningococcal serogroup C polysaccharide and could produce a vaccine to protect against meningococcal disease and to augment protection against pertussis. [source] Biological and sequence comparisons of Potato virus Y isolates associated with potato tuber necrotic ringspot diseasePLANT PATHOLOGY, Issue 2 2002N. Boonham The biological and molecular relationships between a large number of Potato virus Y (PVY) isolates were examined, concentrating mainly on isolates associated with potato tuber necrotic ringspot disease (PTNRD). Following detailed analysis of the coat-protein gene, four main groups were identified which broadly corresponded to the phenotype of the different isolates. The groups comprised the ordinary strain (PVYO), the necrotic strain (PVYN), the C strain (PVYC) and a group of recombinant (between ordinary and necrotic) isolates. In the latter group, all members were associated with PTNRD. However, four nonrecombinant isolates were also identified which were associated with PTNRD or tuber necrosis. Three were from tubers showing PTNRD symptoms in the field, while the fourth originated from symptomless tubers, but could cause necrotic rings on tubers under glasshouse conditions. The results show that although coat-protein recombination is always found associated with the PTNRD phenotype, some nonrecombinant isolates have very similar biological properties. [source] Worldwide distribution of Pseudomonas aeruginosa clone C strains in the aquatic environment and cystic fibrosis patientsENVIRONMENTAL MICROBIOLOGY, Issue 7 2005Ute Römling Summary Highly successful bacterial clones have the ability to effectively colonize environmental niches and patients. However, the factors which determine the complex interplay between the colonization of environmental niches and patients are mainly unknown. In this study we show that Pseudomonas aeruginosa clone C strains are distributed worldwide and highly prone to infect cystic fibrosis (CF) patients in Canada, England, France and Germany. In Hanover, Germany and Vancouver, Canada, clone C strains are highly prevalent in the CF patient community, although the mechanisms of acquisition may have been different. All clone C strains showed highly related macrorestriction fragment pattern of the whole genome as visualized by pulsed-field gel electrophoresis and harboured the 102 kbp plasmid pKLC102. Comparison of three prevalent P. aeruginosa clones with different distribution between the environment and patients revealed that neither enhanced biofilm formation nor antibiotic resistance was responsible for the spread of clone C. Clone M, which was highly prevalent in the clinical environment such as sanitary facilities, lacked motility, which could explain its relatively low prevalence in CF patients. Elucidation of the mechanisms which lead to the prevalence of clone C strain in patients and the environment requires the investigation of additional phenotypes. [source] Functional analysis of the cis -acting elements responsible for the induction of the Cyp6a8 and Cyp6g1 genes of Drosophila melanogaster by DDT, phenobarbital and caffeineINSECT MOLECULAR BIOLOGY, Issue 1 2010R. Morra Abstract Many Drosophila cytochrome P450 or Cyp genes are induced by caffeine and phenobarbital (PB). To understand the induction mechanism, we created Drosophila S2 cell lines stably transformed with different luciferase reporter plasmids carrying upstream DNAs of Cyp6a8 allele of the resistant 91-R strain, and the 1.1-kb upstream DNAs of Cyp6g1 of the 91-R and the susceptible 91-C strains. Following 24 h treatment with dichlorodiphenyltrichloroethane (DDT), caffeine or PB, luciferase activity of all cell lines was determined. Results showed that the 0.1-kb DNA of Cyp6a8 and the upstream DNAs of Cyp6g1 from both strains are not induced by these chemicals in S2 cells. However, the 0.2-, 0.5- and 0.8-kb DNAs of Cyp6a8 showed 13,24-, 4,5- and 2.2,2.7-fold induction with caffeine, PB and DDT, respectively. These DNAs also showed a 2,3-fold synergistic effect of caffeine and PB but not of caffeine and DDT. The results suggest that the cis -regulatory elements for all three chemicals are located within the -11/-199 DNA of Cyp6a8. Furthermore, caffeine and PB inductions appear to be mediated via different cis -elements, whereas caffeine and DDT induction may involve common regulatory elements. These stably transformed cell lines should help understand the mechanism of resistance-associated Cyp gene overexpression in Drosophila. [source] Augmented biosynthesis of cadmium sulfide nanoparticles by genetically engineered Escherichia coliBIOTECHNOLOGY PROGRESS, Issue 5 2009Yen-Lin Chen Abstract Microorganisms can complex and sequester heavy metals, rendering them promising living factories for nanoparticle production. Glutathione (GSH) is pivotal in cadmium sulfide (CdS) nanoparticle formation in yeasts and its synthesis necessitates two enzymes: ,-glutamylcysteine synthetase (,-GCS) and glutathione synthetase (GS). Hereby, we constructed two recombinant E. coli ABLE C strains to over-express either ,-GCS or GS and found that ,-GCS over-expression resulted in inclusion body formation and impaired cell physiology, whereas GS over-expression yielded abundant soluble proteins and barely impeded cell growth. Upon exposure of the recombinant cells to cadmium chloride and sodium sulfide, GS over-expression augmented GSH synthesis and ameliorated CdS nanoparticles formation. The resultant CdS nanoparticles resembled those from the wild-type cells in size (2,5 nm) and wurtzite structures, yet differed in dispersibility and elemental composition. The maximum particle yield attained in the recombinant E. coli was ,2.5 times that attained in the wild-type cells and considerably exceeded that achieved in yeasts. These data implicated the potential of genetic engineering approach to enhancing CdS nanoparticle biosynthesis in bacteria. Additionally, E. coli -based biosynthesis offers a more energy-efficient and eco-friendly method as opposed to chemical processes requiring high temperature and toxic solvents. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009 [source] | |||||||||||||