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Inflammatory odontogenic cysts, if not treated, may lead to progression of osteolytic activity, potential paresthesia, and loss of teeth. A 16-year-old female patient was referred by a pediatric dentist for asymptomatic abnormal radiolucency found interproximally to the mandibular left first and second premolars. Radiographic, clinical, and pathologic analyses led to a diagnosis of an inflamed odontogenic cyst (type K09.0) with Actinomyces colonization. The cyst was treated by periodontal regenerative therapy and resulted in successful osseous regeneration. This was a rare case because of the patient's age, the location of the lesion, its association with vital teeth, and its presentation.

Inflammatory odontogenic cysts, if not treated, may lead to progression of osteolytic activity, potential paresthesia, and loss of teeth. A 16-year-old female patient was referred by a pediatric dentist for asymptomatic abnormal radiolucency found interproximally to the mandibular left first and second premolars. Radiographic, clinical, and pathologic analyses led to a diagnosis of an inflamed odontogenic cyst (type K09.0) with

Geological records from the Antarctic margin offer direct evidence of environmental variability at high southern latitudes and provide insight regarding ice sheet sensitivity to past climate change. The early to mid-Miocene (23-14 Mya) is a compelling interval to study as global temperatures and atmospheric CO2 concentrations were similar to those projected for coming centuries. Importantly, this time interval includes the Miocene Climatic Optimum, a period of global warmth during which average surface temperatures were 3-4 degrees C higher than today. Miocene sediments in the ANDRILL-2A drill core from the Western Ross Sea, Antarctica, indicate that the Antarctic ice sheet (AIS) was highly variable through this key time interval. A multiproxy dataset derived from the core identifies four distinct environmental motifs based on changes in sedimentary facies, fossil assemblages, geochemistry, and paleotemperature. Four major dis-conformities in the drill core coincide with regional seismic discontinuities and reflect transient expansion of grounded ice across the Ross Sea. They correlate with major positive shifts in benthic oxygen isotope records and generally coincide with intervals when atmospheric CO2 concentrations were at or below preindustrial levels (similar to 280 ppm). Five intervals reflect ice sheet minima and air temperatures warm enough for substantial ice mass loss during episodes of high (similar to 500 ppm) atmospheric CO2. These new drill core data and associated ice sheet modeling experiments indicate that polar climate and the AIS were highly sensitive to relatively small changes in atmospheric CO2 during the early to mid-Miocene.

We have studied the effect of lipid-free human plasma apolipoprotein A-I (apoA-I) on the transport of newly synthesized cholesterol to cell-surface cholesterol-rich domains, which in human skin fibroblasts are mainly represented by caveolae. Changes in transport of newly synthesized cholesterol were assessed after labelling cells with [14C]acetate at 15°C and warming cells to permit the transfer of cholesterol, followed by the selective oxidation of cholesterol in cholesterol-rich domains (caveolae) in the plasma membrane before their partial purification. ApoA-I, but not BSA added in an equimolar concentration, enhanced the transport of cholesterol to the caveolae up to 5-fold in a dose- and time-dependent manner. The effect of apoA-I on cholesterol transport exceeded its effect on cholesterol efflux, resulting in an accumulation of intracellular cholesterol in caveolae. Methyl-β-cyclodextrin, added at a concentration promoting cholesterol efflux to the same extent as apoA-I, also stimulated cholesterol trafficking, but was 3-fold less effective than apoA-I. Progesterone inhibited the transport of newly synthesized cholesterol to the caveolae. Treatment of cells with apoA-I stimulated the expression of caveolin, increasing the amount of caveolin protein and mRNA by approx. 2-fold. We conclude that apoA-I induces the transport of intracellular cholesterol to cell-surface caveolae, possibly in part through the stimulation of caveolin expression.

The transfer of insoluble cholesteryl esters among lipoprotein particles is a vital step in normal cholesterol homeostasis and may be involved in the development of atherosclerosis1. Extrahepatic tissues lack the enzymes required for the degradation of sterols to the excretable form of bile acids. Cholesterol synthesized in these tissues in excess of that needed for the synthesis of cell membranes or steroid hormones must accordingly be returned through the plasma to the liver for catabolism. The series of reactions involved has been termed reverse cholesterol transport1. Catalysed steps of this pathway are believed to include an efflux from peripheral cells, which generates a diffusion gradient between these membranes and extracellular fluid; esterification of this cholesterol by lecithin–cholesterol acyltransferase (LCAT) (phosphotidylcholine–sterol acyltransferase) acting on species of high-density lipoproteins; transfer of the cholesteryl esters formed (largely to low- and very low-density lipoproteins) (LDL and VLDL) by a cholesteryl ester transfer protein (CETP); and removal of these lipoproteins, together with their cholesteryl ester content, by the liver through receptor-mediated and nonspecific endocytosis. Of these steps, the CETP reaction is the least characterized. Several laboratories have reported the purification from human plasma of proteins active on cholesteryl ester transfer between lipoprotein particles and possibly between cells and plasma2–5. However, the reported relative molecular mass (Mr), abundance and specificity of the purified activities have differed considerably. We have recently described the preparation of a highly active CETP of Mr 74,000 purified about 100,000-fold from human plasma, which may represent the functional component of earlier preparations6. Using a partial ammo-acid sequence from this purified protein, CETP complementary DNA derived from human liver DNA has been cloned and sequenced and the cloned DNA used to detect CETP messenger RNA in a number of human tissues.

The major objective of the GARTEUR Action Group on Analysis Techniques for Clearance of Flight Control Laws FM(AG-11) is the improvement of the flight clearance process by increased automation of the tools used for model-based analysis of the aircraft’s dynamical behaviour. What is finally needed are techniques for faster detection of the worst case combination of parameter values and manoeuvre cases, from which the flight clearance restrictions are be derived. The basis for such an analysis are accurate mathematical models of the controlled aircraft. In this chapter the HIRM+ flight dynamics model is described as one of the benchmark military aircraft models used within FM(AG-11). HIRM+ originates from the HIRM (High Incidence Research Model) developed within the GARTEUR Action Group on Robust Flight Control FM(AG-08). In building the HIRM+, additional emphasis has been put on realistic modelling of parametric uncertainties.