Search results for "tear"
showing 10 items of 222 documents
COMPUTATIONAL FLUID DYNAMICS OF TYPE B AORTIC DISSECTION
2014
Type B aortic dissection (AoD) is a disease connected to high blood load on the aortic wall and to a reduced aortic wall resistance. Nowadays, prognosis on type B AoD results to be particularly difficult with an high incidence of patients treated with medical therapy which manifest complication connected with dissection and which should have been treated with surgical repair immediately. This work aims to study those haemodynamical and morphological proprieties of dissected aorta, which can influence the progression or stability of type B AoD. Computational fluid-dynamic analyses were performed on twenty-five patients with type B AoD, whose nine presented an aneurysm evolution and sixteen p…
Predicting Outcome of Aortic Dissection with Patent False Lumen by Computational Flow Analysis
2014
Although Type B aortic dissection (AoD) has better in-hospital survival than Type A AoD, the short- and long term outcome for patients remains challenging, with 50–80% deaths at 5-years. Dissection-related complications include rapid aortic expansion, impending rupture, and malperfusion syndromes. We aimed to assess hemodynamic implications of patients with patent false lumen (FL) of dissected aorta. Computational fluid dynamic analyses were performed on patient-specific aortic geometries reconstructed from computed tomography scans of 25 patients with AoDs, who were admitted in our hospital from 2007 to 2013. We used the development of acute complications and chronic aneurysmal evolution a…
“Beyond Weather Regimes”: Descriptors Monitoring Atmospheric Centers of Action. A case study for Aotearoa New Zealand
2021
AbstractThis paper introduces a set of descriptors applied to weather regimes, that allow for a detailed monitoring of the location and intensity of their atmospheric centers of action (e.g. troughs and ridges) and the gradients between them, when applicable. Descriptors are designed to document the effect of climate variability and change in modulating the character of daily weather regimes, rather than merely their occurrence statistics.As a case study, the methodology is applied to Aotearoa New Zealand (ANZ), using ERA5 ensemble reanalysis data for the period 1979-2019. Here, we analyze teleconnections between the regimes and their descriptors, and large-scale climate variability. Result…
Euonymus maackii Rupr. Seed oil as a new potential non-edible feedstock for biodiesel
2019
Abstract In this study, Euonymus maackii Seed oil (EMSO) was exploited and evaluated for the first time as a new non-edible oil feedstock for preparation of biodiesel. The EMSO yield was 41.06 ± 2.68 wt%. The fatty acid compositions of EMSO involved palmitoleic acid (2.01%), palmitic acid (14.5%), stearic acid (3.1%), oleic acid (49.8%), linoleic acid (29.3%), 11-Eicosenoic acid (0.1%) and arachidic acid (0.07%). Microwave-assisted transesterification with methanol provided a high conversion yield in short duration under low temperature. The 2.0 wt% of catalyst amount, 10:1 of methanol/oil molar ratio, 40 min of reaction time and 60 °C of temperature were found to be the optimum process condi…
Liver oleic acid biogenesis is impaired during the prehypertensive period in the spontaneously hypertensive rat.
2003
In the present study, we have investigated the liver microsomal stearic acid delta9 desaturation, and the fatty acid composition of liver microsomal total lipids in 10- and 30-day-old spontaneously hypertensive rats (SHRs), compared to the normotensive Wistar Kyoto (WKY) control rats. So as to avoid any influence related to the diet, the composition of the milk being different in SHR and WKY strains, the pups were suckled by adoptive normotensive female Wistar. After weaning, the 30-day-old rats were fed a standard commercial diet and then killed. Our results show lower liver microsomal delta9 desaturase activities in the 10- and 30-day-old SHR versus the WKY of the same age. The fatty acid…
Chronic exposure of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) induces an obesogenic effect in C57BL/6J mice fed a high fat diet
2017
IF 3.582; International audience; Contaminant involvement in the pathophysiology of obesity is widely recognized. It has been shown that low dose and chronic exposure to endocrine disruptor compounds (EDCs) potentiated diet- induced obesity. High and acute exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), a persistent organic pollutant (POP) and an EDC with anti-estrogenic property, causes wasting syndrome . However at lower doses, the TCDD metabolic effects remain poorly understood. We investigated the obesogenic effect during chronic exposure of TCDD at 1μg/kg body weight (bw)/week in adult C57BL/6J mice fed with a high fat diet (HFD) and exposed from 10 to 42 weeks old to TCDD or e…
Changes in meibomian fatty acids and ocular surface in patients with meibomian gland dysfunction after minocycline treatment
2008
International audience; Purpose:Tear film lipid layer (TFLL) is a very structured layer with essential functions. Its structure is highly dependent on chemical and physical characteristics of lipids composing the TFLL We previously published alterations in the composition of TFLL in patients suffering from meibomian gland dysfunction (MGD). Branched chain fatty acids (BCFA) were significantly increased, suggesting that BCFA may be associated with the disease. The aim of this study was to evaluate the effect of a treatment by oral minocycline associated to lid hygiene versus lid hygiene only on changes in ocular surface abnormalities and in meibomian fatty acid composition in patients suffer…
Inhibition of stearoyl-CoA desaturase 1 expression induces CHOP-dependent cell death in human cancer cells.
2010
Background Cancer cells present a sustained de novo fatty acid synthesis with an increase of saturated and monounsaturated fatty acid (MUFA) production. This change in fatty acid metabolism is associated with overexpression of stearoyl-CoA desaturase 1 (Scd1), which catalyses the transformation of saturated fatty acids into monounsaturated fatty acids (e.g., oleic acid). Several reports demonstrated that inhibition of Scd1 led to the blocking of proliferation and induction of apoptosis in cancer cells. Nevertheless, mechanisms of cell death activation remain to be better understood. Principal Findings In this study, we demonstrated that Scd1 extinction by siRNA triggered abolition of de nov…
Phase composition of Fe-containing Langmuir-Blodgett layers after thermal treatment in a reactive atmosphere
1993
By the Langmuir-Blodgett technique, mono- and multilayers of ferric stearate were drawn onto silicon wafers. They were thermodesorbed in air at 250–300°C, and the layers formed in this way were found to consist of γ-FeOOH with defective stoichiometry. By heating in H2, the layers can be reduced to Fe2− and even to α-Fe. The latter is magnetically ordered and highly corrosion resistant. Chloride ions, however, induce fast corrosion. FeCl2, formed by this corrosion, is rather unstable and transforms to an Fe3+ phase. The high corrosion resistance of the metallic Fe layer is assumed to be due to its excellent homogeneity. The experiments were performed using XPS, AES, CEMS, and SEM.
CEMS/XPS study of iron stearate Langmuir-Blodgett layers
1991
Langmuir-Blodgett mono- and multilayers of ferric stearate have been formed on oxidized silicon wafers. Thermodesorption of these layers was investigated by conversion electron Mossbauer and photoelectron spectroscopy and some complementary methods. Heating of samples in air up to 523 K leads to a desorption of the fatty acid chains, while the ferric ions are left on the substrate surface. These ions do not cluster laterally like it was found for Cd ions. They form a rather homogeneous, closed oxidic layer. This well defined layer may be used afterwards for further studies of surface reactions as well as interface and intra-layer interactions. The surface iron ions were found to exhibit a r…