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Mt. Vesuvius is one of the most studied volcanoes in the world and its proximity to an extremely populated area makes it also one of the most threatening. Violent Strombolian (VS) events have occurred in the most recent history of the volcano, and they are the type most likely to occur in case of reactivation of the volcano in the near future. In order to investigate the dynamics and hazard of this type of eruption, we performed new field and laboratory work and numerical simulations of plume dynamics, fallout and tephra dispersal associated with such eruptions. Attention was specifically focused on the 1906 eruption, a recent and well-studied VS event. Based on new field analyses and historical observations, we reconstructed the temporal evolution of eruption source conditions during the event. The reconstructed explosive phase of the eruption is inferred to have been 8 days long and characterized by two distinct stages: a former short and intense period with sustained convective plume fed by powerful lava fountains (20 h) followed by a prolonged and less intense period of ash emission (172 h). The total grain-size distributions for both phases, used as inputs to the model, were obtained by field work and laboratory analyses. Based on these new volcanological data and reconstruction of wind field direction and intensity, partially derived from historical sources, the 1906 event was numerically simulated and results compared to deposit distributions. The modelling outcomes for the ash emission phase provide a better agreement with the measured tephra mass load for a simulation run in which ash aggregation (described by the models of Cornell et al. J Volcanol Geotherm Res 17:89-109, , and Biass et al. Nat Hazard Earth Syst Sci 14:2265-2287, ) is specifically taken into account, confirming the importance of this process during tephra dispersal. The aggregation model that best fits the simulated results to the measured ground loadings has 80 % of particles Φ ≥ 4 that aggregate uniformly in the range Φ = −1 to 3. Two additional simulations of a VS event were carried out by using meteorological data of two specific periods to exemplify weather's potential on impacts of such eruptions, particularly tephra loading, on the surrounding areas. The model outcomes clearly highlight the major effects of differences in local meteorology on plume dynamics and ash dispersal and the key role of wind shear in determining the cumulative thickness of ground deposits. Results also show that, due to the long duration of this kind of eruption and the large variability in zonal winds at this latitude, ash dispersal and fallout from VS events at Vesuvius represent a probable hazard for all of the territory near Vesuvius, including the city of Naples, where cumulative tephra loadings might reach critical thresholds for roof collapse and infrastructure damage. [ABSTRACT FROM AUTHOR]

The time to achieve good metabolic control after diagnosis is essential for type 2 diabetes patients because it can influence long-term prognosis. This study aimed to elucidate the predictive role of several clinical and organization factors in normalizing metabolism within 6 months. A multi-centered, retrospective, observational study on 960 patients, with diabetes duration of 12 months or less, consecutively seen in 123 Italian clinics, was undertaken. Information about clinic’s organization, along with data abstracted from medical records at enrollment (first visit) and after 6 months (follow-up visit), was collected. At 6 months, HbA1c dropped by -3.1 ± 2.2 points in those who achieved HbA1c <7 % (responders), whereas in non-responders (HbA1c ≥7 %), the mean reduction was -1.8 ± 1.9. The intervention markedly reduced lipids, blood pressure, BMI, and waist circumference, especially in responders. The presence of a diabetes team correlated with a likelihood of HbA1c normalization (OR 1.94, 1.17–3.22). By contrast, indicators of advanced disease such as previous retinopathy (0.53, 0.29–0.98), use of secretagogues (0.40, 0.25–0.64), high levels of HbA1c at first visit and related insulin use emerged as adverse factors. Early detection of diabetes, along with human resources and organization, was found to play a crucial role in rapidly attaining good metabolic control. [ABSTRACT FROM AUTHOR]

: Cholesterol esterification and smooth muscle cell (SMC) proliferation are the crucial events in the development of atherosclerotic lesions. The objective of this study was to analyse cholesterol esterification and the expression of MDR1 (multidrug resistance), ACAT (acyl-CoA:cholesterol acyltransferase) and caveolin-1 genes in atherosclerotic and healthy vascular walls, in SMCs obtained from atherosclerotic lesions and saphenous veins. Results demonstrated higher levels of cholesterol esters, ACAT and MDR1 mRNAs and lower levels of caveolin-1 mRNA in atherosclerotic segments compared to adjacent serial sections of the same artery and the corresponding non-atherosclerotic arteries from cadaveric donors. SMCs isolated from atherosclerotic plaques manifested an increased capacity to esterify cholesterol and to grow at a faster rate than SMCs isolated from saphenous veins. In addition, when SMCs from atherosclerotic plaques were cultured in the presence of progesterone, a potent inhibitor of cholesterol esterification, significant growth suppression was observed. An increase in ACAT and MDR1 expression and a concomitant decrease in caveolin-1 expression were also observed in SMCs isolated from atherosclerotic arteries as early as 12 h after serum stimulation. An opposite pattern was found when SMCs were treated with progesterone. These findings support the idea that cholesterol esterification plays a role both in early atherogenesis and in clinical progression of advanced lesions and raise the possibility that the cholesterol ester pathway might directly modulate the proliferation of SMCs. [ABSTRACT FROM AUTHOR]

The product of the MDR1 gene (P-gp) has been implicated in the transport of cholesterol from plasma membrane to endoplasmic reticulum for esterification. In previous studies on leukemia cell lines, we suggested that cholesterol esterification may regulate the rate of cell growth and that the MDR1 gene might be involved in this process by modulating intracellular cholesterol esters levels. To further investigate this matter, the rate of cell growth, cholesterol metabolism, expression of the MDR1 gene, and P-gp activity were compared in KB cell lines displaying differences in expression and function of P-gp (drug-sensitive phenotype versus MDR phenotype). The rate of cell growth correlated with cholesterol esterification in all KB cell lines, whereas the over-expression of MDR1 observed in the MDR cell lines was not always associated with an increased capacity of cells to esterify cholesterol. Two known inhibitors of P-gp activity, progesterone and verapamil, strongly inhibited both cholesterol esterification and cell proliferation in all KB cell lines, but they affected intracellular accumulation of labeled vinblastine only in MDR cell lines. These results further support a role for cholesterol esters in the regulation of cell growth and suggest that the P-gp expressed in MDR KB cells is not involved in the general process leading to cholesterol esterification. [ABSTRACT FROM AUTHOR]

The aim of our study was to evaluate the contrast-enhanced MR imaging (MRI) findings, in the early postoperative period, in unselected patients undergoing lumbar microdiscectomy (15/16 had total resolution of their symptoms). Contrast-enhanced imaging studies were performed, in all 16 patients of our series, before surgery, and at the third postoperative day and, two months after surgery. Postoperative paraspinal muscles enhancement was present in all patients. In the postoperative period, nerve root enhancement was present in 5/16 patients at the early survey and persisted in one after two months. A pseudohernia depicted as epidural intermediate signal intensity tissue, was seen in 13 patients at the third day MRI, and only in eight after two months. This pseudohernia enhanced peripherally in 8/13 patients and enhanced homogeneously in the remaining five at the first postsurgical examination; in the late MRI the peripheral enhancement was appreciable in only two patients while a homogeneous enhancement was observed in six. Clinical symptoms resolved completely in 14/16 patients on clinical evaluation at the third postoperative day, while the remaining two patients showed residual symptoms and signs of radicular compression. At the early MRI these two patients showed intradural nerve root enhancement. Two months later, one patient did not show the previously described nerve root enhancement and improved clinically, while the other had a positive Straight Leg Raising Sign with persistent intradural nerve root enhancement. In conclusion, no correlation between clinical course and contrastenhancement of pseudohernia and extradural nerve root was appreciable, although intradural nerve root enhancement seems to represent a clinically relevant finding. [ABSTRACT FROM AUTHOR]

Intranigral administration of kainic acid results in loss of pars reticulata neurons without damage to axons traversing or terminating within the nigra. Unilateral nigral lesions with kainic acid result in an ipsilateral turning upon administration of apomorphine, a dopamine (DA)-receptor agonist and in contralateral turning upon administration of haloperidol, a DA-receptor blocker. Destruction of post-synaptic structures in the striatum of the side contralateral to that injected with kainic acid results in a drastic reduction, abolition or even reversal of the turning effects elicited by apomorphine and haloperidol. Unilateral intranigral microinjection of nanogram amounts of the GABA-receptor antagonists picrotoxin and bicuculline elicits ipsilateral circling upon apomorphine administration. Kainic-induced lesion or micro-injection of picrotoxin or bicuculline in the nigra ipsilateral to a 6-OHDA-lesion of nigro-striatal DA-neurons results in reduction, abolition or reversal of the contralateral circling produced by apomorphine. The results indicate that the nigra pars reticulata is a station for dopaminergic impulses originating from the striatum and suggest that the turning behavior in response to striatal DA-receptor stimulation is due to a GABA-mediated inhibition of ipsiversive pars reticulata neurons. [ABSTRACT FROM AUTHOR]