Search results for "Low density"
showing 10 items of 77 documents
Influence of a sterically hindered amine on the photo-oxidation of low density/linear low density polyethylene blends
1990
Abstract Low density/linear low density polyethylene blends show a rate of degradation of the mechanical properties during photo-oxidation which increases with the content of the linear polymer. The use of a sterically hindered amine as UV stabilizer greatly improves the resistance of these blends to UV irradiation. The effectiveness of the stabilizer increases with the content of linear low density polyethylene.
MoSi2 laser cladding—a comparison between two experimental procedures: Mo–Si online combination and direct use of MoSi2
2001
International audience; There are very strong interests in developing low density advanced material systems for service at temperatures up to 1300°C. These materials should mainly have moderate fracture toughness at low and intermediate temperatures and should exhibit oxidation resistant behaviour. The intermetallic compound, MoSi2 has been considered to be an attractive candidate due to its melting point (2030°C) and excellent oxidation resistance at high temperatures. In this paper, we compare the results obtained with two different techniques for laser cladding, one using an online combination between Mo and Si powders, the second using direct injection of the MoSi2 powder.
The clinical significance of small, dense low-density lipoproteins
2006
Peak size of low-density lipoproteins (LDL) in humans does not show a normal, but a bimodal distribution and can be separated into two phenotypes, that differ in size, density, physicochemical composition, metabolic behavior, and atherogenicity. These phenotypes have been assigned as pattern A when larger, more buoyant LDL and pattern B when smaller, more dense LDL predominate. Small dense LDL correlates negatively with plasma HDL levels and positively with plasma triglyceride concentrations and is associated with the metabolic syndrome and increased risk for cardiovascular disease. LDL size seems to be an important predictor of cardiovascular events and progression of coronary heart diseas…
Oxidative stress and small, dense low-density lipoproteins: current and future perspectives
2019
Small, dense low-density lipoproteins (LDLs) are more susceptible to oxidation than their larger, more buoyant counterparts and therefore the biological modification of these LDL particles may, in part, be responsible for their atherogenic properties. Kotani et al. found that at multiple regression analysis there was an independent and significant inverse correlation between the mean LDL particle size and the oxidative stress status; notably, the authors adjusted not only for the traditional cardiovascular risk factors, but also for drug treatments. Higher levels of small, dense LDL concentrations significantly contribute to atherosclerosis, and lipoprotein size and subfractions may refine …
Peroxydation in vivo et in vitro des acides gras polyinsaturés
2007
It is well admitted that polyunsaturated fatty acids are the most sensitive fatty acids to oxidative damage because of their high number of double bonds. This concept could not be confirmed by in vitro, animal, or human studies since unexpected or even contradictory results were obtained. The explanation of that is probably related to the methods evaluating lipid peroxidation whose relevance is not always established, but especially to movements of polyunsaturated fatty acids within lipoproteins that results in their protection. This short review aims to discuss the main results related to this topic.
Evaluation of the primary stability in dental implants placed in low density bone with a new drilling technique, osseodensification: an in vitro study
2020
Background Primary stability is an important key determinant of implant osseointegration. We investigated approaches to improve primary implant stability using a new drilling technique termed osseodensification (OD), which was compared with the conventional under-drilling (UD) method utilized for low-density bones. Material and Methods We placed 55 conical internal connection implants in each group, in 30 low-density sections of pig tibia. The implants were placed using twist drill bits in both groups; groups Under Drilling (UD) and Osseodensification (OD) included bone sections subjected to conventional UD and OD drilling, respectively. Before placing the implants, we randomized the bone s…
Mycobacterium tuberculosis Drives Expansion of Low-Density Neutrophils Equipped With Regulatory Activities
2019
In human tuberculosis (TB) neutrophils represent the most commonly infected phagocyte but their role in protection and pathology is highly contradictory. Moreover, a subset of low-density neutrophils (LDNs) has been identified in TB, but their functions remain unclear. Here, we have analyzed total neutrophils and their low-density and normal-density (NDNs) subsets in patients with active TB disease, in terms of frequency, phenotype, functional features, and gene expression signature. Full-blood counts from Healthy Donors (H.D.), Latent TB infected, active TB, and cured TB patients were performed. Frequency, phenotype, burst activity, and suppressor T cell activity of the two different subse…
A novel putative interactor for the low density lipoprotein receptor cytoplasmic domain
2011
Familial hypercholesterolemia (FH) is a genetic disease mainly caused by mutations in the low density lipoprotein receptor (LDLLDLLDL-R) gene. However, FH-like phenotypes may also arise from mutations occurring in other genes, the products of which normally interact with the LDLLDLLDL receptor. Although several FH-associated proteins have been discovered, many FH-like phenotypes cannot be linked to mutations in already characterized genes, suggesting the existence of other genes still to be identified, the mutations of which may be directly linked to the FH disorder. In order to identify new putative LDLLDLLDLr interactors possibly involved in its internalization and/or sorting, the cytopla…
Lipoprotein Subfractions in Metabolic Syndrome and Obesity: Clinical Significance and Therapeutic Approaches
2013
Small, dense low density lipoprotein (sdLDL) represents an emerging cardiovascular risk factor, since these particles can be associated with cardiovascular disease (CVD) independently of established risk factors, including plasma lipids. Obese subjects frequently have atherogenic dyslipidaemia, including elevated sdLDL levels, in addition to elevated triglycerides (TG), very low density lipoprotein (VLDL) and apolipoprotein-B, as well as decreased high density lipoprotein cholesterol (HDL-C) levels. Obesity-related co-morbidities, such as metabolic syndrome (MetS) are also characterized by dyslipidaemia. Therefore, agents that favourably modulate LDL subclasses may be of clinical value in t…
Size and subclasses of low-density lipoproteins in patients with obstructive sleep apnea.
2012
Patients with obstructive sleep apnea (OSA) have proatherogenic dyslipidemia. We analyzed predictors of low-density lipoproteins' (LDLs) size in patients with OSA. In a cross-sectional study including 58 participants with OSA (30 without the metabolic syndrome [MetS] and 28 with MetS), we evaluated the size of LDL by gradient gel electrophoresis. Compared with patients without the MetS, those with MetS showed lower LDL size ( P = .007), due to a reduction in large LDL-I particles ( P = .002) and an increase in small, dense LDL-IIIA ( P = .048) and LDL-IIIB ( P = .037). The size of LDL correlated inversely with age ( r = −.268, P = .042) and serum triglycerides ( r = −.364, P = .005), and p…