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71.
Victor K Goh Chu-Pak Lau Stefan Mohlenkamp John A Rumberger Stephan Achenbach Matthew J Budoff 《Cardiovascular ultrasound》2010,8(1):1-11
Estimation of left ventricular (LV) mass has both prognostic and therapeutic value independent of traditional risk factors. Unfortunately, LV mass evaluation has been underestimated in clinical practice. Assessment of LV mass can be performed by a number of imaging modalities. Despite inherent limitations, conventional echocardiography has fundamentally been established as most widely used diagnostic tool. 3-dimensional echocardiography (3DE) is now feasible, fast and accurate for LV mass evaluation. 3DE is also superior to conventional echocardiography in terms of LV mass assessment, especially in patients with abnormal LV geometry. Cardiovascular magnetic resonance (CMR) and cardiovascular computed tomography (CCT) are currently performed for LV mass assessment and also do not depend on cardiac geometry and display 3-dimensional data, as well. Therefore, CMR is being increasingly employed and is at the present standard of reference in the clinical setting. Although each method demonstrates advantages over another, there are also disadvantages to receive attention. Diagnostic accuracy of methods will also be increased with the introduction of more advanced systems. It is also likely that in the coming years new and more accurate diagnostic tests will become available. In particular, CMR and CCT have been intersecting hot topic between cardiology and radiology clinics. Thus, good communication and collaboration between two specialties is required for selection of an appropriate test. 相似文献
72.
Polymer conjugation increases an enzyme's circulation time and stability for use as a therapeutic agent, but this attachment indubitably affects its properties. Covalent attachment of multiple polyethylene glycol chains with sizes of either 2, 5, 10, or 20 kDa increases the molecular weight and hydrodynamic radius of the model enzyme trypsin. The sizes of these polymer-enzyme conjugates are increased to be within the recommended limits for PDEPT applications. The T(d) increases from 49 to 60 °C to expand the enzyme's workable range of conditions. This functionalization with PEG polymers of varying lengths maintains trypsin's enzymatic activity. Conjugate activities are 79-120% that of native trypsin at room temperature and 221-432% that of trypsin at 37 °C. 相似文献
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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
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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
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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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