This article provides an overview of methods for reliability assessment of quantitative structure-activity relationship (QSAR) models in the context of regulatory acceptance of human health and ...environmental QSARs. Useful diagnostic tools and data analytical approaches are highlighted and exemplified. Particular emphasis is given to the question of how to define the applicability borders of a QSAR and how to estimate parameter and prediction uncertainty. The article ends with a discussion regarding QSAR acceptability criteria. This discussion contains a list of recommended acceptability criteria, and we give reference values for important QSAR performance statistics. Finally, we emphasize that rigorous and independent validation of QSARs is an essential step toward their regulatory acceptance and implementation.
The complexation kinetics for the polyaminopolycarboxylic ligand DTPA to lanthanides in acidic aqueous solution were investigated using the dye ligand displacement technique and stopped-flow ...spectroscopy. Significant rate differences were obtained for different dye probes used, indicating that the kinetics of the dissociation of the dye molecule significantly impacts the overall measured kinetics when using this common methodology. The conditions of the solution also influenced the dye-lanthanide-DTPA interactions, which reconciled previously disparate data in the literature.
Applications of SELDI‐MS technology in oncology Whelan, L. C.; Power, K. A. R.; McDowell, D. T. ...
Journal of cellular and molecular medicine,
September/October 2008, Volume:
12, Issue:
5a
Journal Article
Peer reviewed
Open access
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Introduction
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Surface enhanced laser desorption/ionisation‐mass spectrometry
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Sampling
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Clinical applications
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Detection and diagnosis
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Pre‐operative staging of disease
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Predicting ...response to therapy
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Metastasis and disease progression
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Drug resistance
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In vitro applications
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Cell culture models
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Protein interactions
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Advantages over conventional technologies
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Limitations
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Conclusions
Considerable interest, speculation and controversy have been generated utilising surface‐enhanced laser desorption/ionization in conjunction with mass spectrometry (SELDI‐MS) for the diagnosis, prognosis and therapeutic monitoring of cancer and offers an attractive approach to cancer biomarker discovery from tissues and biological fluids. This technology utilises a combination of mass spectrometry and chromatography to facilitate protein profiling of complex biological mixtures. Compared to some other more traditional proteomic platforms, such as 2D polyacrylamide gel electrophoresis, it has a high‐throughput capability and can resolve low‐mass proteins. However, a considerable number of challenging issues related to the design of studies, including reproducibility, sensitivity, specificity, variation in sample collection, processing and storage, have been reported as problematic with this technology; albeit some of these concerns could perhaps also be lauded against other proteomic approaches that have attempted to address complex protein mixtures, such as plasma. Applications, successes and limitations of SELDI‐MS in both clinical and basic science arenas will be reviewed in this article.
Purpose
The internet has revolutionised the way we search for information. We determined the level of internet use by parents of children attending general surgical services and identified trends in ...online information-seeking behaviour.
Methods
A questionnaire based on the work by Boston and Tassone was distributed to parents attending both the day surgical units and surgical outpatients department in a paediatric tertiary referral centre.
Results
There were 214 (82.3 %) questionnaires returned, with 82 (38.3 %) of respondents having searched the internet regarding their child’s surgical issue. Access to a smartphone, a university education and private health insurance were factors that positively influenced online searching (
p
< 0.005). Of those respondents who searched the internet, 42 (51 %) felt that information they found online was understandable, while only 14 (17 %) admitted to online sourced information influencing the treatment decisions they had made for their children. When asked to rank information sources on Likert-type scales in terms of importance; parents ranked the surgeon as most important (mean = 4.73), whilst the internet ranked lowest (mean = 3.02).
Conclusion
We demonstrated significant use of the internet amongst those attending paediatric general surgical services. Clinician sourced information remains important, however we should engage with patients to utilise this vast resource effectively.
Antibacterial activity of human natural killer cells GARCIA-PENARRUBIA, P; KOSTER, F. T; KELLEY, R. O ...
The Journal of experimental medicine,
1989, 1989-Jan-01, 1989-01-01, 19890101, Volume:
169, Issue:
1
Journal Article
Peer reviewed
Open access
The in vitro effects of human NK cells on viability of Gram-negative and Gram-positive bacteria was investigated. PBLs depleted of glass-adherent cells showed a significant antibacterial activity ...that was increased as the concentration of NK cells became higher. Leu-11-enriched cells exhibited the most efficient bactericidal activity. Stimulation of NK cells with staphylococcal enterotoxin B for 16 h produced a significant increase in the antibacterial activity of all NK cells tested. The antibacterial activity of monocyte-depleted cells and Leu-11-enriched cells was also enhanced after culturing in vitro for 16-24 h without exogenous cytokines. Dependence of the antibacterial activity on the presence of serum in the culture medium was not found. Ultrastructural studies revealed close contact between NK cell membranes and bacteria, no evidence of phagocytosis, and extracellular bacterial ghosts, after incubation at 37 degrees C. Supernatants from purified NK cells exhibited potent bactericidal activity with kinetics and target specificity similar to that of effector cells. These results document the potent antibacterial activity of purified NK cells and suggest an extracellular mechanism of killing.
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