28 research outputs found
A europium complex that selectively stains nucleoli of cells
A europium complex selectively staining the nucleolus of NIH 3T3, HeLa, and HDF cells is reported. This complex possesses not only the advantage of the long lifetime of europium emission (0.3 ms), but also a chromophore that allows excitation at a relatively long wavelength (lambda(max) = 384 nm) and gives rise to an acceptable quantum yield (9%). The complex can be used both in live cell and fixed cell imaging, giving an average intracellular concentration on the order of 0.5 mu M. Strong binding to serum albumin has been demonstrated by examination of the analogous gadolinium complex, studying relaxivity changes with increasing protein concentration. The intracellular speciation of the complex has been examined by circularly polarized emission spectroscopy and is consistent with the presence of more than one europium species, possibly protein bound
Clinical presentation of rheumatic fever in an endemic area
This study documented whether patients diagnosed with Acute Rheumatic Fever (ARF) in North Queensland, Australia conformed to the 1992 Revised Jones Criteria (RJC). We aimed to determine whether inclusion of subclinical carditis (SCC) and monoarthritis as major manifestations and a low-grade temperature as a minor manifestation in the RJC are justified in this population. A retrospective review of patients in whom the diagnosis of ARF relied on the experience of clinicians and who were admitted to the Townsville and Cairns Base Hospitals between 1997 and 2007 was undertaken. Of the 98 cases reviewed, 71.4% satisfied the RJC. Modification of the RJC increased the rate of criteria satisfaction to 91.8%. On presentation, 27 patients had SCC. Of the patients with SCC followed up, 70.5% had long-term valvular consequences. In populations endemic for ARF, monoarthritis, SCC and a low-grade temperature should be included in the RJ
Quantifying rates of coastal progradation from sediment volume using GPR and OSL: the Holocene fill of Guichen Bay, southeast South Australia
Guichen Bay on the southâeast coast of South Australia faces west towards the prevailing westerly winds of the Southern Ocean. The bay is backed by a 4âkm wide Holocene beachâridge plain with more than 100 beach ridges. The morphology of the Guichen Bay strandplain complex shows changes in the width, length, height and orientation of beach ridges. A combination of geomorphological interpretation, shallow geophysics and existing geochronology is used to interpret the Holocene fill of Guichen Bay. Six sets of beach ridges are identified from the interpretation of orthorectified aerial photographs. The ridge sets are distinguished on the basis of beachâridge orientation and continuity. A 2·25âkm groundâpenetrating radar (GPR) profile across the beach ridges reveals the sedimentary structures and stratigraphic units. The beach ridges visible in the surface topography are a succession of stabilized foredunes that overlie progradational foreshore and upper shoreface sediments. The beach progrades show multiple truncation surfaces interpreted as storm events. The GPR profile shows that there are many more erosion surfaces in the subsurface than beach ridges on the surface. The width and dip of preserved beach progrades imaged by GPR shows that the shoreface has steepened from around 2·9° to around 7·5°. The changes in beach slope are attributed to increasing wave energy associated with beach progradation into deeper water as Guichen Bay was infilled. At the same time, the thickness of the preserved beach progrades increases slightly as the beach prograded into deeper water. Using the surface area of the ridge sets measured from the orthophotography, and the average thickness of upper shoreface, foreshore and coastal dune sands interpreted from the GPR profile, the volume of Holocene sediments within three of the six sets of beachâridge accretion has been calculated. Combining optically stimulated luminescence (OSL) ages and volume calculations, rates of sediment accumulation for Ridge Sets 3, 4 and 5 have been estimated. Linear rates of beachâridge progradation appear to decrease in the midâHolocene. However, the rates of sediment accumulation calculated from beach volumes have remained remarkably consistent through the midâ to late Holocene. This suggests that sediment supply to the beach has been constant and that the decrease in the rate of progradation is due to increasing accommodation space as the beach progrades into deeper water. Changes in beachâridge morphology and orientation reflect environmental factors such as changes in wave climate and wind regime