51 research outputs found

    Qualitative and Quantitative Detection of Chlamydophila pneumoniae DNA in Cerebrospinal Fluid from Multiple Sclerosis Patients and Controls

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    A standardized molecular test for the detection of Chlamydophila pneumoniae DNA in cerebrospinal fluid (CSF) would assist the further assessment of the association of C. pneumoniae with multiple sclerosis (MS). We developed and validated a qualitative colorimetric microtiter plate-based PCR assay (PCR-EIA) and a real-time quantitative PCR assay (TaqMan) for detection of C. pneumoniae DNA in CSF specimens from MS patients and controls. Compared to a touchdown nested-PCR assay, the sensitivity, specificity, and concordance of the PCR-EIA assay were 88.5%, 93.2%, and 90.5%, respectively, on a total of 137 CSF specimens. PCR-EIA presented a significantly higher sensitivity in MS patients (p = 0.008) and a higher specificity in other neurological diseases (p = 0.018). Test reproducibility of the PCR-EIA assay was statistically related to the volumes of extract DNA included in the test (p = 0.033); a high volume, which was equivalent to 100 µl of CSF per reaction, yielded a concordance of 96.8% between two medical technologists running the test at different times. The TaqMan quantitative PCR assay detected 26 of 63 (41.3%) of positive CSF specimens that tested positive by both PCR-EIA and nested-PCR qualitative assays. None of the CSF specimens that were negative by the two qualitative PCR methods were detected by the TaqMan quantitative PCR. The PCR-EIA assay detected a minimum of 25 copies/ml C. pneumoniae DNA in plasmid-spiked CSF, which was at least 10 times more sensitive than TaqMan. These data indicated that the PCR-EIA assay possessed a sensitivity that was equal to the nested-PCR procedures for the detection of C. pneumoniae DNA in CSF. The TaqMan system may not be sensitive enough for diagnostic purposes due to the low C. pneumoniae copies existing in the majority of CSF specimens from MS patients

    A buoyancy technique for measuring plant volumes

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    Volume measurements of plant organs are not commonly used in the analysis of plant growth. Volume is, however, a useful, non-destructive measure of plant size and is particularly suitable for plants growing in water culture. All techniques of measuring plant volumes that are described in the literature measure the volume of a liquid that is displaced by the immersion of the plant material. The "buoyancy" technique is based on the principle of Archimedes and is an improvement on displacement methods in that it is sensitive to very small volumes, does not damage plants and is extremely rapid.Keywords: buoyancies|plants|measurements|volumes|plant organs|apparatus|techniques|plant growth|plant sizes|displacements|volume measurements|Archimedes|method

    Sugarcane

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    Key Messages:\ud \ud It is likely that the greatest direct climate change impact (and adaptation challenge) on Australian sugarcane production will be the projected change in the amount, frequency and intensity of future rainfall. In many of the sugarcane growing regions the amount of effective rainfall available to the crop will be reduced, while demand is likely to increase due to increased rates of evapotranspiration linked to atmospheric warming.\ud \ud A range of adaptation strategies (both tactical and strategic) is needed across the entire sugar cane industry value chain if it is to remain sustainable under a changing climate. Strategies must be tailored to individual mill regions to take account of location-specific biophysical and logistical impacts.\ud \ud Adaptation options available to the sugarcane industry include improvements to the management of limited water supplies; technological fixes based on reductionist analysis; engineering design principles, or computer-aided modelling; altered cropping system design and agronomic management; enhanced utilisation of decision-making tools, and effective institutional change (Park et al. 2007a).\ud \ud Building capacity through targeted extension, improving skills and providing a more industry-wide knowledge base are all essential for future adaptation.\ud \ud Many adaptation strategies involve an enhancement or extension of existing activities aimed at building resilience to climatic variability. Additional longer-term adaptation options will also need to be iteratively developed and evaluated in an adaptive management context if the industry is to remain sustainable into the future.\u
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