Use of variability in national and regional data to estimate the prevalence of lymphangioleiomyomatosis

Background: Understanding the true prevalence of lymphangioleiomyomatosis (LAM) is important in estimating disease burden and targeting specific interventions. As with all rare diseases, obtaining reliable epidemiological data is difficult and requires innovative approaches. Aim: To determine the prevalence and incidence of LAM using data from patient organizations in seven countries, and to use the extent to which the prevalence of LAM varies regionally and nationally to determine whether prevalence estimates are related to health-care provision. Methods: Numbers of women with LAM were obtained from patient groups and national databases from seven countries (n = 1001). Prevalence was calculated for regions within countries using female population figures from census data. Incidence estimates were calculated for the USA, UK and Switzerland. Regional variation in prevalence and changes in incidence over time were analysed using Poisson regression and linear regression. Results: Prevalence of LAM in the seven countries ranged from 3.4 to 7.8/million women with significant variation, both between countries and between states in the USA. This variation did not relate to the number of pulmonary specialists in the region nor the percentage of population with health insurance, but suggests a large number of patients remain undiagnosed. The incidence of LAM from 2004 to 2008 ranged from 0.23 to 0.31/million women/per year in the USA, UK and Switzerland. Conclusions: Using this method, we have found that the prevalence of LAM is higher than that previously recorded and that many patients with LAM are undiagnose

Technological homogeneity within the Arabian Nubian Complex: Comparing chert and quartzite assemblages from central and southern Arabia

Nubian Levallois technology is the defining characteristic of the Middle Paleolithic or Middle Stone Age technocomplex known as the Nubian Complex. Until recently, this technocomplex was found exclusively in northeastern Africa; however, archaeological surveys conducted across the Arabian Peninsula in the last decade have expanded the known distribution of this technological phenomenon. Since 2009, researchers from separate archaeological missions have mapped sites yielding Nubian cores and debitage, and by extension Nubian technology, in the southern, central and northernmost parts of the Arabia Peninsula. Nubian Complex artifacts in central and southern Arabia were made using different raw materials: in Al-Kharj (central Saudi Arabia) Middle Paleolithic industries were made exclusively on quartzite, while in Dhofar (southern Oman) chert was the only knappable material available for use. Given these differences, we sought to examine the influence of raw material variability on core morphology and size. Contrary to initial hypothesis, this study finds that the differences recorded are not a function of raw material properties. In both areas, Nubian cores were reduced using the same technological systems producing a set of preferential blanks. Rather, the recorded differences from raw material constrains were primarily due to knapping accidents, which occur in higher proportions at quartzite-based assemblages from Al-Kharj (specifically the siret fracture) compared with the chert assemblages from Dhofar. In sum, we argue that raw material had little effect on Nubian Levallois core technology and was not a constraint on Nubian Complex artisans

A Spatial Distribution Study of Faunal Remains from Two Lower Magdalenian Occupation Levels in El Mirón Cave, Cantabria, Spain

Abstract: Human behaviour can be reconstructed by analysing specific activities and campsite organization using spatial analysis. The dense occupation layers of the Lower Cantabrian Magdalenian in the Northern Spain reveal varied aspects of Upper Palaeolithic lifeways, including evidence of specific localized activities. The outer vestibule of El Mirón cave has a particularly rich and intact Lower Magdalenian occupation horizon, Levels 15–17. The excavations in the outer vestibule “Cabin” area of the site revealed excellent bone preservation. Artefacts and faunal remains were individually recorded and sediments water-screened to yield a large sample of archaeological finds and spatial data. Zooarchaeological analysis provided the taxonomic, anatomic and taphonomic determination of the faunal individual finds. Smaller animal remains were categorized and counted; special attention was given to the identification of anthropogenic modifications such as burnt bones or bone flakes. These small refuse items are considered to be useful, in situ indicators of localized activities. The spatial distribution analysis of this dense and complex palimpsest of El Mirón Lower Cantabrian Magdalenian layers required GIS based methods including density analysis, heatmaps and cluster analysis. Based on the spatial distribution of Level 15 and 16 faunal remains, different activity areas were identified comprising hearth, working and dropping zones. These results imply the deliberately segregated use of space within the Lower Cantabrian Magdalenian site area, in which bone-processing activities played a central rol

Glutamate-mediated release of Ca2+ in mitral cells of the olfactory bulb

1. Effects of glutamate on intracellular Ca2+ concentration ([Ca2+]i) were investigated in cultured olfactory bulb neurons of Xenopus laevis tadpoles. We imaged [Ca2+]i in these cells with the use of a confocal laser scanning microscope and the calcium indicator dyes Fluo3 and FuraRed. 2. In the standard bath solution, application of glutamate through a pipette resulted in an increase of [Ca2+]i in both mitral/ tufted (M/T) cells and interneurons. The increase occurred in all compartments of the cells, although in a nonhomogenous way. 3. In an ethylene glycol-bis(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid-buffered bath solution (Ca(2+)-free Ringer solution), glutamate reproducibly induced an increase of [Ca2+]i in M/T cells but not in interneurons. This increase in [Ca2+]i had the following properties: 1) it was delayed with respect to the combined ionotropic and metabotropic response to glutamate, 2) in some cases it stopped before the end of the glutamate application, and 3) it was not affected by D,L-2-amino-5-phosphonopentanoic acid and 6-cyano-7-nitroquinoxaline-2,3-dione added to the bath. It was interpreted as a release of Ca2+ from intracellular calcium stores. 4. Of 47 M/T cells that showed a glutamate-mediated release of [Ca2+]i, 46 also showed Ca2+ influx through ionotropic glutamate receptors, so that intracellular release of [Ca2+]i appeared to be associated with the presence of glutamate-gated ion channels. However, of 110 M/T cells showing an ionotropic response to glutamate, only 46 showed a glutamate-mediated release of [Ca2+]i. 5. The glutamate-mediated release of [Ca2+]i in the dendrites was higher than that in the soma. No indications for calcium waves were found. 6. Quisqualate and (1S,3R)-1-aminocyclopentane-1,3-dicarboxylic acid (ACPD) mimicked the effect of glutamate on the release of [Ca2+]i, with potencies quisqualate &gt; glutamate &gt; &gt; ACPD. N-acetyl-aspartyl-glutamate did not induce release of [Ca2+]i. The release was partly blocked by (+)-alpha-methyl-4-carboxyphenylglycine. 7. In conclusion, some but not all M/T cells of the olfactory bulb of X. laevis show a glutamate-mediated and predominantly dendritic increase of [Ca2+]i that is associated with glutamategated channels. The pharmacological properties of the corresponding metabotropic glutamate receptor (mGluR) resemble those of the mGluR1/5 receptors in rat. </jats:p