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71.
72.
Standley SM Mende I Goh SL Kwon YJ Beaudette TT Engleman EG Fréchet JM 《Bioconjugate chemistry》2007,18(1):77-83
The development of multicomponent biotherapeutic carriers is an important challenge in the field of drug delivery, particularly in the area of protein-based vaccines. While the delivery of protein antigens to antigen presenting cells (APCs) is crucial for this type of vaccination, the incorporation of additional adjuvants may be just as important in order to generate more potent immune responses. This article presents the synthesis and biological evaluation of carrier particles that both deliver a protein payload to APCs and display receptor ligands for the enhancement of APC immunostimulation. Particles displaying CpG oligonucleotide ligands for Toll-like receptor 9 were synthesized. The addition of CpG DNA to the particles led to a 45-fold increase in the secretion of interleukin-12, a cytokine that aids in T-cell activation, and a significant increase in the expression of costimulatory molecules by APCs. Moreover, vaccination with particles containing both ovalbumin (OVA) and CpG DNA induced a superior OVA-specific CD8 T-cell response in vivo, as measured by increased OVA-specific CD8 T-cell proliferation, secretion of the proinflammatory cytokine IFN-gamma, and the induction of OVA-specific cytotoxicity. 相似文献
73.
Leuko S Goh F Allen MA Burns BP Walter MR Neilan BA 《Extremophiles : life under extreme conditions》2007,11(1):203-210
Hamelin Pool in Western Australia is one of the two major sites in the world with active marine stromatolite formation. Surrounded
by living smooth and pustular mats, these ancient laminated structures are associated with cyanobacterial communities. Recent
studies have identified a wide diversity of bacteria and archaea in this habitat. By understanding and evaluating the microbial
diversity of this environment we can obtain insights into the formation of early life on Earth, as stromatolites have been
dated in the geological record as far back as 3.5 billion years. Automated ribosomal intergenic spacer analysis (ARISA) patterns
were shown to be a useful method to genetically discriminate halophilic archaea within this environment. Patterns of known
halophilic archaea are consistent, by replicate analysis, and the halophilic strains isolated from stromatolites have novel
intergenic spacer profiles. ARISA–PCR, performed directly on extracted DNA from different sample sites, provided significant
insights into the extent of previous unknown diversity of halophilic archaea within this environment. Cloning and sequence
analysis of the spacer regions obtained from stromatolites confirmed the novel and broad diversity of halophilic archaea in
this environment. 相似文献
74.
75.
We have recently reported biodegradable cationic micelles self-assembled from an amphiphilic copolymer, poly{(N-methyldietheneamine sebacate)-co-[(cholesteryl oxocarbonylamido ethyl)methyl bis(ethylene)ammonium bromide]sebacate} (P(MDS-co-CES)), which were utilized to deliver a drug and nucleic acid simultaneously, and a synergistic effect was achieved. In this paper, synthesis and characterization of the polymer is presented in details, focusing on micelle formation and DNA binding under various conditions, cytotoxicity, in-vitro degradation, and gene transfection in various cell lines. The polymer was degradable and formed micelles at very low concentrations even in an environment with high salt concentration. These micelles fabricated at pH 4.6 had an average size of less than 82 nm and zeta potential of up to 84 +/- 5 mV, displaying strong DNA binding ability. They induced high gene expression efficiency in various cell lines, which was significantly greater than poly(ethylenimine) (PEI) especially in 4T1 mouse and MDA-MB-231 human breast cancer cell lines, but they were less cytotoxic. These cationic micelles may provide a promising nonviral vector for gene delivery. 相似文献
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79.
Olivier Monteuuis Doreen K. S. Goh Charles Garcia David Alloysius Jikos Gidiman Roberto Bacilieri Gilles Chaix 《Tree Genetics & Genomes》2011,7(6):1263-1275
Forty-two different genetic origins of teak (Tectona grandis) comprising 26 open-pollinated families from a clonal seed orchard (CSO) were planted in a replicated trial under 2,500 mm
of annual rainfall and no distinct dry season, in 1997, in Sabah, East Malaysia. The trees were measured or scored for various
traits at 13, 35, 49, 61, 72, 85, 96, and 106 months after planting. Mortality rate, height (H), diameter at breast height
(DBH), volume (V), and fork height (FH) varied strongly among populations and origins. The best population means after 106 months for growth
H (21.1 m), DBH (21.1 cm), and V (278 dm3) were for the CSO families. Narrow sense heritabilities for the CSO families increased gradually with age but remained lower
after 106 months for DBH (h
2 = 0.24) and V (h
2 = 0.34) than for H (h
2 = 0.51) and FH (h
2 = 0.56). Overall, the CSO families were also straighter, less forked, and grew more vertically than the native provenance
and seed-derived sources. Such differences did not exist for flowering ability, and at 106 months, the great majority of the
trees of the various origins had not yet entered the flowering stage. Overall, at 106 months, the phenotypic correlations
between the various quantitative and qualitative traits were weak, except between straightness and bending with values higher
than 0.50. These findings confirm the usefulness of CSO for teak improvement and demonstrate the beneficial influence of wet
tropical conditions on traits of major economical importance for this species. 相似文献
80.
Rice blast, caused by the pathogen Magnaporthe oryzae, is a serious hindrance to rice production and has emerged as an important model for the characterization of molecular mechanisms relevant to pathogenic development in plants. Similar to other pathogenic fungi, conidiation plays a central role in initiation of M.oryzae infection and spread over a large area. However, relatively little is known regarding the molecular mechanisms that underlie conidiation in M. oryzae. To better characterize these mechanisms, we identified a conidiation-defective mutant, ATMT0225B6 (MoCDC15(T-DNA)), in which a T-DNA insertion disrupted a gene that encodes a homolog of fission yeast cdc15, and generated a second strain containing a disruption in the same allele (ΔMoCDC15(T-DNA)). The cdc15 gene has been shown to act as a coordinator of the cell cycle in yeast. Functional analysis of the MoCDC15(T-DNA) and ΔMoCDC15(T-DNA) mutants revealed that MoCDC15 is required for conidiation, preinfection development and pathogenicity in M. oryzae. Conidia from these mutants were viable, but failed to adhere to hydrophobic surface, a crucial step required for subsequent pathogenic development. All phenotypic defects observed in mutants were rescued in a strain complemented with wild type MoCDC15. Together, these data indicate that MoCDC15 functions as a coordinator of several biological processes important for pathogenic development in M. oryzae. 相似文献