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1.
Eur Phys J C Part Fields ; 83(6): 467, 2023.
Article de Anglais | MEDLINE | ID: mdl-37303462

RÉSUMÉ

The ICARUS collaboration employed the 760-ton T600 detector in a successful 3-year physics run at the underground LNGS laboratory, performing a sensitive search for LSND-like anomalous νe appearance in the CERN Neutrino to Gran Sasso beam, which contributed to the constraints on the allowed neutrino oscillation parameters to a narrow region around 1 eV2. After a significant overhaul at CERN, the T600 detector has been installed at Fermilab. In 2020 the cryogenic commissioning began with detector cool down, liquid argon filling and recirculation. ICARUS then started its operations collecting the first neutrino events from the booster neutrino beam (BNB) and the Neutrinos at the Main Injector (NuMI) beam off-axis, which were used to test the ICARUS event selection, reconstruction and analysis algorithms. ICARUS successfully completed its commissioning phase in June 2022. The first goal of the ICARUS data taking will be a study to either confirm or refute the claim by Neutrino-4 short-baseline reactor experiment. ICARUS will also perform measurement of neutrino cross sections with the NuMI beam and several Beyond Standard Model searches. After the first year of operations, ICARUS will search for evidence of sterile neutrinos jointly with the Short-Baseline Near Detector, within the Short-Baseline Neutrino program. In this paper, the main activities carried out during the overhauling and installation phases are highlighted. Preliminary technical results from the ICARUS commissioning data with the BNB and NuMI beams are presented both in terms of performance of all ICARUS subsystems and of capability to select and reconstruct neutrino events.

2.
HLA ; 90(3): 183-184, 2017 09.
Article de Anglais | MEDLINE | ID: mdl-28670878

RÉSUMÉ

HLA-DRB1*14:186 differs from DRB1*14:58 by a non-synonymous mutation at nucleotide 227 in exon 2.


Sujet(s)
Allèles , Moelle osseuse , Exons , Chaines HLA-DRB1/génétique , Donneurs de tissus , Femelle , Humains , Italie , Mâle
3.
Bone Joint J ; 97-B(10 Suppl A): 30-9, 2015 Oct.
Article de Anglais | MEDLINE | ID: mdl-26430084

RÉSUMÉ

Primary total knee arthroplasty (TKA) is a reliable procedure with reproducible long-term results. Nevertheless, there are conditions related to the type of patient or local conditions of the knee that can make it a difficult procedure. The most common scenarios that make it difficult are discussed in this review. These include patients with many previous operations and incisions, and those with severe coronal deformities, genu recurvatum, a stiff knee, extra-articular deformities and those who have previously undergone osteotomy around the knee and those with chronic dislocation of the patella. Each condition is analysed according to the characteristics of the patient, the pre-operative planning and the reported outcomes. When approaching the difficult primary TKA surgeons should use a systematic approach, which begins with the review of the existing literature for each specific clinical situation.


Sujet(s)
Arthroplastie prothétique de genou/méthodes , Articulation du genou/chirurgie , Gonarthrose/complications , Gonarthrose/chirurgie , Humains , Anomalies morphologiques acquises des articulations/complications , Anomalies morphologiques acquises des articulations/chirurgie , Articulation du genou/anatomopathologie , Ostéotomie , Luxation patellaire/complications , Luxation patellaire/chirurgie , Soins préopératoires , Réintervention , Résultat thérapeutique
5.
Minerva Gastroenterol Dietol ; 57(1): 89-96, 2011 Mar.
Article de Anglais | MEDLINE | ID: mdl-21372773

RÉSUMÉ

Crohn's disease is a chronic transmural inflammatory disease that most commonly affects the intestinal wall, but may also occur in any part of the gastrointestinal tract; its incidence is higher in industrialized countries, urban areas and upper socioeconomic classes. Various environmental risk factors have been associated with the pathogenesis of Crohn's disease and possible infectious agents (viruses, bacteria, yeasts) have also been considered. However, none of these factors alone leads to the development of the disease, which may occur only when there is a genetic predisposition and/or an abnormal function of the intestinal immune system. Histopathology demonstrates mucosal hyperemia, with small superficial ulcers in mild forms of the disease; in moderate-to-severe forms, serpiginous ulcerations demarcating areas of edematous mucosa produce the characteristic "cobblestone" appearance. The earliest microscopic lesions appear as neutrophil-mediated cryptic damage, with the formation of focal cryptic abscesses and granulomas throughout the layers of the intestinal wall. In addition to weight loss, patients mainly refer chronic diarrhea and recurrent right iliac fossa abdominal pain. Extraintestinal manifestations include ocular or articular complications. There are several drugs classes available for treating Crohn's disease, but the therapeutic approach depends on the clinical picture and differs from patient to patient. The broad clinical and the histopathological features of Crohn's disease make it a highly polymorphic entity. Diagnostic tests and a thorough knowledge of its various aspects are essential for guiding diagnosis and treatment.


Sujet(s)
Maladie de Crohn , Douleur abdominale/étiologie , Antibactériens/usage thérapeutique , Anti-infectieux/usage thérapeutique , Maladies de l'anus/étiologie , Maladie chronique , Maladie de Crohn/complications , Maladie de Crohn/diagnostic , Maladie de Crohn/épidémiologie , Maladie de Crohn/étiologie , Maladie de Crohn/thérapie , Diagnostic différentiel , Diarrhée/étiologie , Association de médicaments , Maladies de l'oeil/étiologie , Humains , Incidence , Italie/épidémiologie , Maladies articulaires/étiologie , Maladies du rein/étiologie , Maladies du foie/étiologie , Facteurs de risque , Maladies de la peau/étiologie , Maladies vasculaires/étiologie
6.
Aliment Pharmacol Ther ; 31(2): 228-32, 2010 Jan 15.
Article de Anglais | MEDLINE | ID: mdl-19817724

RÉSUMÉ

BACKGROUND: Acute pouchitis, an idiopathic inflammatory condition of the ileal pouch anal anastomosis, is the most frequent complication after proctocolectomy for ulcerative colitis. AIM: To test the hypothesis that sulfasalazine (SASP) might have a synergistic beneficial effect in acute pouchitis, by combining the anti-inflammatory activity of 5-aminosalicylic Acid and the bacteriostatic effect of sulphapyridine. METHODS: Twenty two patients were investigated for acute pouchitis; the Pouchitis Disease Activity Index (PDAI) was calculated and 11 patients with acute pouchitis (PDAI >7) were included in an open study, after obtaining their informed consent. Patients were treated with SASP 500 mg tablets, two tablets three times per day (3000 mg daily), for 2 months. Pouch endoscopy with biopsies was performed at the entry and at the end of the study. RESULTS: According to the PDAI score, 8/11 patients (73%) improved their clinical condition and 7/11 (63%) were in remission at the end of the treatment. At 8 weeks, the median PDAI index decreased from 11.2 +/- 2.3 to 6.6 +/- 4.7 P < 0.01. No adverse events or toxicity were reported and all patients completed the study. CONCLUSIONS: Despite the limitations of the current study, sulfasalazine seems to be a potential treatment for acute pouchitis.


Sujet(s)
Poches coliques/anatomopathologie , Muqueuse intestinale/anatomopathologie , Mésalazine/usage thérapeutique , Pochite/traitement médicamenteux , Proctocolectomie restauratrice/effets indésirables , Sulfasalazine/usage thérapeutique , Adulte , Femelle , Humains , Mâle , Adulte d'âge moyen , Projets pilotes , Pochite/étiologie , Pochite/anatomopathologie , Indice de gravité de la maladie , Résultat thérapeutique , Jeune adulte
7.
J Lipid Res ; 50(5): 880-4, 2009 May.
Article de Anglais | MEDLINE | ID: mdl-19141870

RÉSUMÉ

Apolipoprotein AV (apoAV) overexpression causes a decrease in plasma triglyceride (TG) levels, while deficiency of apoAV causes hypertriglyceridemia in both men and mice. However, contrary to what would be expected, plasma apoAV and TG levels in humans are positively correlated. To address this apparent paradox, we determined plasma apoAV levels in various mouse models with median TG levels ranging from 30 mg/dl in wild-type mice to 2089 mg/dl in glycosylphosphatidylinositol-anchored HDL binding protein 1-deficient mice. The data show that apoAV and TG levels are positively correlated in mice (r = +0.798, P < 0.001). In addition, we show that LPL gene transfer caused a simultaneous decrease in TG and apoAV in LPL-deficient mice. The combined data suggest that apoAV levels follow TG levels due to an intimate link between the apoAV molecule and TG-rich lipoproteins, comprising both secretion and removal of these lipoproteins. Taken together, the data suggest that higher plasma apoAV levels reflect an increased demand for plasma TG hydrolysis under normal physiological conditions.


Sujet(s)
Apolipoprotéines A/sang , Triglycéride/sang , Animaux , Apolipoprotéine A-V , Humains , Lipoprotein lipase/génétique , Mâle , Souris , Souris de lignée C57BL , Souris knockout
9.
Diabetologia ; 51(6): 978-88, 2008 Jun.
Article de Anglais | MEDLINE | ID: mdl-18421434

RÉSUMÉ

AIMS/HYPOTHESIS: We previously used an integrative genetics approach to demonstrate that 5-lipoxygenase (5-LO) deficiency in mice (Alox5 (-/-)) protects against atherosclerosis despite increasing lipid levels and fat mass. In the present study, we sought to further examine the role of 5-LO in adiposity and pancreatic function. METHODS: Alox5 (-/-) and wild-type (WT) mice were characterised with respect to adiposity and glucose/insulin metabolism using in vivo and in vitro approaches. The role of ALOX5 in pancreatic function in human islets was assessed through short interfering RNA (siRNA) knockdown experiments. RESULTS: Beginning at 12 weeks of age, Alox5 (-/-) mice had significantly increased fat mass, plasma leptin levels and fasting glucose levels, but lower fasting insulin levels (p<0.05). Although Alox5 (-/-) mice did not exhibit insulin resistance, they had impaired insulin secretion in response to a bolus glucose injection. Histological analyses revealed that Alox5 (-/-) mice had increased islet area, beta cell nuclear size, and numbers of beta cells/mm(2) islet (p<0.05), indicative of both hyperplasia and hypertrophy. Basal and stimulated insulin secretion in isolated Alox5 (-/-) islets were significantly lower than in WT islets (p<0.05) and accompanied by a three- to fivefold decrease in the expression of the genes encoding insulin and pancreatic duodenal homeobox 1 (Pdx1). Direct perturbation of ALOX5 in isolated human islets with siRNA decreased insulin and PDX1 gene expression by 50% and insulin secretion by threefold (p<0.05). CONCLUSIONS/INTERPRETATION: These results provide strong evidence for pleiotropic metabolic effects of 5-LO on adiposity and pancreatic function and may have important implications for therapeutic strategies targeting this pathway for the treatment of cardiovascular disease.


Sujet(s)
Tissu adipeux/enzymologie , Tissu adipeux/physiologie , Protéines de transport/génétique , Protéines membranaires/déficit , Protéines membranaires/génétique , Pancréas/enzymologie , Protéines d'activation de la 5-lipoxygénase , Animaux , Arachidonate 5-lipoxygenase/déficit , Arachidonate 5-lipoxygenase/génétique , Glycémie/métabolisme , Composition corporelle , Poids , Croisements génétiques , Femelle , Hyperglycémie provoquée , Humains , Insuline/sang , Insuline/métabolisme , Sécrétion d'insuline , Ilots pancréatiques/enzymologie , Ilots pancréatiques/métabolisme , Leptine/sang , Mâle , Souris , Souris de lignée C57BL , Souris knockout , ARN/génétique , ARN/isolement et purification , Interférence par ARN , Petit ARN interférent/génétique , Caractères sexuels , Donneurs de tissus
10.
Oncogene ; 27(4): 528-39, 2008 Jan 17.
Article de Anglais | MEDLINE | ID: mdl-17637741

RÉSUMÉ

In this study, we delineate the intracellular signalling pathways modulated by a conditional v-Src tyrosine kinase that lead to unrestrained proliferation and block of differentiation of primary avian myoblasts. By inhibiting Ras-MAPK kinase and phosphatidylinositol 3-kinase with different means, we find that both pathways play crucial roles in controlling v-Src-sustained growth factor and anchorage independence for proliferation. The Ras-MAPK kinase pathway also contributes to block of differentiation independently of cell proliferation since inhibition of this pathway both in proliferating and growth-arrested v-Src-transformed myoblasts induces expression of muscle-specific genes, fusion into multinucleated myotubes and assembly of specialized contractile structures. Importantly, we find that the p38 MAPK pathway is inhibited by v-Src in myoblasts and its forced activation results in growth inhibition and expression of differentiation, indicating p38 MAPK as a critical target of v-Src in growth transformation and myogenic differentiation. Furthermore, we show that downregulation of p38 MAPK activation may occur via Ras-MAPK kinase, thus highlighting a cross-regulation between the two pathways. Finally, we report that the simultaneous inhibition of MAPK kinase and calpain, combined to activation of p38 MAPK, are sufficient to reconstitute largely the differentiation potential of v-Src-transformed myoblasts.


Sujet(s)
Transformation cellulaire néoplasique/génétique , Myoblastes squelettiques/anatomopathologie , Protéine oncogène pp60(v-src)/physiologie , Transduction du signal/génétique , Animaux , Adhérence cellulaire/physiologie , Différenciation cellulaire/physiologie , Lignée de cellules transformées , Prolifération cellulaire , Transformation cellulaire néoplasique/métabolisme , Cellules cultivées , Embryon de poulet , Mitogen-Activated Protein Kinase Kinases/physiologie , Modèles biologiques , Myoblastes squelettiques/métabolisme , Phosphatidylinositol 3-kinases/physiologie , Protéines proto-oncogènes p21(ras)/physiologie , Caille , Transfection
14.
Oncogene ; 22(27): 4221-34, 2003 Jul 03.
Article de Anglais | MEDLINE | ID: mdl-12833145

RÉSUMÉ

The ErbB-2 interacting protein receptor-associated late transducer (RALT) was previously identified as a feedback inhibitor of ErbB-2 mitogenic signals. We now report that RALT binds to ligand-activated epidermal growth factor receptor (EGFR), ErbB-4 and ErbB-2.ErbB-3 dimers. When ectopically expressed in 32D cells reconstituted with the above ErbB receptor tyrosine kinases (RTKs) RALT behaved as a pan-ErbB inhibitor. Importantly, when tested in either cell proliferation assays or biochemical experiments measuring activation of ERK and AKT, RALT affected the signalling activity of distinct ErbB dimers with different relative potencies. RALT deltaEBR, a mutant unable to bind to ErbB RTKs, did not inhibit ErbB-dependent activation of ERK and AKT, consistent with RALT exerting its suppressive activity towards these pathways at a receptor-proximal level. Remarkably, RALT deltaEBR retained the ability to suppress largely the proliferative activity of ErbB-2.ErbB-3 dimers over a wide range of ligand concentrations, indicating that RALT can intercept ErbB-2.ErbB-3 mitogenic signals also at a receptor-distal level. A suppressive function of RALT deltaEBR towards the mitogenic activity of EGFR and ErbB-4 was detected at low levels of receptor occupancy, but was completely overcome by saturating concentrations of ligand. We propose that quantitative and qualitative aspects of RALT signalling concur in defining identity, strength and duration of signals generated by the ErbB network.


Sujet(s)
Protéines de transport/composition chimique , Protéines de transport/métabolisme , Récepteurs ErbB/métabolisme , Protéines et peptides de signalisation intracellulaire , Protein-Serine-Threonine Kinases , Récepteur ErbB-2/métabolisme , Transduction du signal , Cellules 3T3 , Animaux , Division cellulaire , Lignée cellulaire , ADN/métabolisme , Dimérisation , Relation dose-effet des médicaments , Activation enzymatique , Antienzymes/pharmacologie , Glutathione transferase/métabolisme , Immunochimie , Immunohistochimie , Ligands , Souris , Microscopie confocale , Microscopie de fluorescence , Mitogen-Activated Protein Kinases/métabolisme , Modèles génétiques , Mutation , Facteur de croissance dérivé des plaquettes/métabolisme , Liaison aux protéines , Structure tertiaire des protéines , Protéines proto-oncogènes/métabolisme , Protéines proto-oncogènes c-akt , Récepteurs à activité tyrosine kinase/antagonistes et inhibiteurs , Récepteur ErbB-4 , Protéines de fusion recombinantes/métabolisme , Transfection
15.
Radiat Prot Dosimetry ; 99(1-4): 343-6, 2002.
Article de Anglais | MEDLINE | ID: mdl-12194319

RÉSUMÉ

The electronics employed around particle accelerators can be disturbed or damaged because of single event effects (SEE). The most likely effect is the single event upset (SEU) which may affect all memory devices. In the case of high energy accelerators, SEUs are mostly produced by secondary charged particles generated by neutron interactions. The measurement of the energy and the lineal energy distribution of these neutron-induced charged particles was proposed. As a first approach, a commercial p-i-n photodiode was employed. This device was irradiated with thermal and monoenergetic fast neutrons. Some effects limiting the use of such a detector as a SEE spectrometer were observed, giving guidelines for the design of an application specific integrated circuit (ASIC). The possibility of creating a solid state microdosemeter by coupling the ASIC with a tissue-equivalent radiator is discussed. Moreover, the p-i-n photodiode covered with a hydrogenated plastic radiator may be employed as a proton-recoil spectrometer.


Sujet(s)
Semiconducteurs , Relation dose-effet des rayonnements , Études de faisabilité , Neutrons , Analyse spectrale/méthodes
16.
Ann Hum Genet ; 66(Pt 1): 37-48, 2002 Jan.
Article de Anglais | MEDLINE | ID: mdl-12014999

RÉSUMÉ

For this study we consulted the Bone Marrow Donors' Registry of Lombardy (Italy) and analyzed 43937 HLA-A,B phenotypes and 13922 HLA-A,B,DR phenotypes. We estimated the HLA-A,B and HLA-A,B,DR haplotype frequencies via the maximum-likelihood method. We analyzed the genetic structure of the 11 provinces of Lombardy by means of Principal Component Analysis and Correspondence Analysis, and estimated the variety of the different haplotypes at provincial level and the percentage of unique phenotypes at village level. We found 11189 different HLA-A,B phenotypes, 661 different HLA-A,B haplotypes and more than 4000 different HLA-A,B,DR haplotypes. We identified 20 villages, in Western Lombardy, very rich in unique/rare phenotypes. Here we report a formula which allows the identification of a putative donor matched for two haplotypes with a recipient. This result may be of great importance for the genetic study of the population of Lombardy and, even more, for bone marrow transplantation programs.


Sujet(s)
Transplantation de moelle osseuse , Moelle osseuse/immunologie , Antigènes HLA/génétique , Antigènes HLA-DR/génétique , Haplotypes , Test d'histocompatibilité/méthodes , Donneurs de tissus , Allèles , Fréquence d'allèle , Antigènes HLA/immunologie , Antigènes HLA-A/génétique , Antigènes HLA-A/immunologie , Antigènes HLA-B/génétique , Antigènes HLA-B/immunologie , Antigènes HLA-DR/immunologie , Humains , Immunogénétique , Italie , Phénotype , Polymorphisme génétique , Enregistrements , Population rurale
18.
J Lipid Res ; 42(4): 563-70, 2001 Apr.
Article de Anglais | MEDLINE | ID: mdl-11290828

RÉSUMÉ

Studies with mice have revealed that increased expression of apolipoprotein A-II (apoA-II) results in elevations in high density lipoprotein (HDL), the formation of larger HDL, and the development of early atherosclerosis. We now show that the increased size of HDL results in part from an inhibition of the ability of hepatic lipase (HL) to hydrolyze phospholipids and triglycerides in the HDL and that the ratio of apoA-I to apoA-II determines HDL functional and antiatherogenic properties. HDL from apoA-II transgenic mice was relatively resistant to the action of HL in vitro. To test whether HL and apoA-II influence HDL size independently, combined apoA-II transgenic/HL knockout (HLko) mice were examined. These mice had HDL similar in size to apoA-II transgenic mice and HLko mice, suggesting that they do not increase HDL side by independent mechanisms. Overexpression of apoA-I from a transgene reversed many of the effects of apoA-II overexpression, including the ability of HDL to serve as a substrate for HL. Combined apoA-I/apoA-II transgenic mice exhibited significantly less atherosclerotic lesion formation than did apoA-II transgenic mice. These results were paralleled by the effects of the transgenes on the ability of HDL to protect against the proinflammatory effects of oxidized low density lipoprotein (LDL). Whereas nontransgenic HDL protected against oxidized LDL induction of adhesion molecules in endothelial cells, HDL from apoA-II transgenic mice was proinflammatory. HDL from combined apoA-I/apoA-II transgenic mice was equally as protective as HDL from nontransgenic mice. Our data suggest that as the ratio of apoA-II to apoA-I is increased, the HDL become larger because of inhibition of HL, and lose their antiatherogenic properties.


Sujet(s)
Apolipoprotéine A-II/métabolisme , Apolipoprotéine A-I/métabolisme , Artériosclérose/métabolisme , Triacylglycerol lipase/métabolisme , Lipoprotéines HDL/métabolisme , Animaux , Aorte/anatomopathologie , Apolipoprotéine A-I/génétique , Apolipoprotéine A-II/génétique , Artériosclérose/étiologie , Artériosclérose/anatomopathologie , Adhérence cellulaire/physiologie , Cholestérol/sang , Régime athérogène , Endothélium vasculaire/cytologie , Humains , Lipides/sang , Lipoprotéines HDL/composition chimique , Foie/enzymologie , Mâle , Souris , Souris knockout , Souris transgéniques , Monocytes/métabolisme
19.
J Biol Chem ; 276(26): 23304-11, 2001 Jun 29.
Article de Anglais | MEDLINE | ID: mdl-11323427

RÉSUMÉ

The finding that expression of a cholesterol 7alpha-hydroxylase (CYP7A1) transgene in cultured rat hepatoma cells caused a coordinate increase in lipogenesis and secretion of apoB-containing lipoproteins led to the hypothesis that hepatic production of apoB-containing lipoproteins may be linked to the expression of CYP7A1 (Wang, S.-L., Du, E., Martin, T. D., and Davis, R. A. (1997) J. Biol. Chem. 272, 19351-19358). To examine this hypothesis in vivo, a transgene encoding CYP7A1 driven by the constitutive liver-specific enhancer of the human apoE gene was expressed in C56BL/6 mice. The expression of CYP7A1 mRNA (20-fold), protein ( approximately 10-fold), and enzyme activity (5-fold) was markedly increased in transgenic mice compared with non-transgenic littermates. The bile acid pool of CYP7A1 transgenic mice was doubled mainly due to increased hydrophobic dihydroxy bile acids. In CYP7A1 transgenic mice, livers contained approximately 3-fold more sterol response element-binding protein-2 mRNA. Hepatic expression of mRNAs encoding lipogenic enzymes (i.e. fatty-acid synthase, acetyl-CoA carboxylase, stearoyl-CoA desaturase, squalene synthase, farnesyl-pyrophosphate synthase, 3-hydroxy-3-methylglutaryl-CoA reductase, and low density lipoprotein receptor) as well as microsomal triglyceride transfer protein were elevated approximately 3-5-fold in transgenic mice. CYP7A1 transgenic mice also displayed a >2-fold increase in hepatic production and secretion of triglyceride-rich apoB-containing lipoproteins. Despite the increased hepatic secretion of apoB-containing lipoproteins in CYP7A1 mice, plasma levels of triglycerides and cholesterol were not significantly increased. These data suggest that the 5-fold increased expression of the low density lipoprotein receptor displayed by the livers of CYP7A1 transgenic mice was sufficient to compensate for the 2-fold increase production of apoB-containing lipoproteins. These findings emphasize the important homeostatic role that CYP7A1 plays in balancing the anabolic lipoprotein assembly/secretion pathway with the cholesterol catabolic bile acid synthetic pathway.


Sujet(s)
Apolipoprotéines B/biosynthèse , Cholesterol 7-alpha-hydroxylase/physiologie , Foie/enzymologie , Animaux , Apolipoprotéine B-100 , Apolipoprotéines B/sang , Apolipoprotéines B/métabolisme , Acides et sels biliaires/métabolisme , Protéines liant les séquences stimulatrices de type CCAAT/biosynthèse , Protéines liant les séquences stimulatrices de type CCAAT/génétique , Protéines de transport/métabolisme , Cholestérol/métabolisme , Cholesterol 7-alpha-hydroxylase/génétique , Protéines de liaison à l'ADN/biosynthèse , Protéines de liaison à l'ADN/génétique , Hyperlipidémies/sang , Métabolisme lipidique , Lipides/sang , Foie/métabolisme , Souris , Souris de lignée C57BL , Souris transgéniques , ARN messager/biosynthèse , Récepteurs aux lipoprotéines LDL/biosynthèse , Récepteurs aux lipoprotéines LDL/génétique , Protéine-1 de liaison à l'élément de régulation des stérols , Protéine-2 de liaison à l'élément de régulation des stérols , Acide taurochénodésoxycholique/métabolisme , Facteurs de transcription/biosynthèse , Facteurs de transcription/génétique , Triglycéride/sang
20.
Arterioscler Thromb Vasc Biol ; 21(4): 481-8, 2001 Apr.
Article de Anglais | MEDLINE | ID: mdl-11304461

RÉSUMÉ

Oxidation of low density lipoprotein (LDL) phospholipids containing arachidonic acid at the sn-2 position occurs when a critical concentration of "seeding molecules" derived from the lipoxygenase pathway is reached in LDL. When this critical concentration is reached, the nonenzymatic oxidation of LDL phospholipids produces a series of biologically active, oxidized phospholipids that mediate the cellular events seen in the developing fatty streak. Normal high density lipoprotein (HDL) contains at least 4 enzymes as well as apolipoproteins that can prevent the formation of the LDL-derived oxidized phospholipids or inactivate them after they are formed. In the sense that normal HDL can prevent the formation of or inactivate these inflammatory LDL-derived oxidized phospholipids, normal HDL is anti-inflammatory. HDL from mice that are genetically predisposed to diet-induced atherosclerosis became proinflammatory when the mice are fed an atherogenic diet, injected with LDL-derived oxidized phospholipids, or infected with influenza A virus. Mice that were genetically engineered to be hyperlipidemic on a chow diet and patients with coronary atherosclerosis, despite normal lipid levels, also had proinflammatory HDL. It is proposed that LDL-derived oxidized phospholipids and HDL may be part of a system of nonspecific innate immunity and that the detection of proinflammatory HDL may be a useful marker of susceptibility to atherosclerosis.


Sujet(s)
Artériosclérose/métabolisme , Inflammation/métabolisme , Lipoprotéines HDL/métabolisme , Lipoprotéines LDL/métabolisme , Phospholipides/métabolisme , Animaux , Artériosclérose/diagnostic , Artériosclérose/physiopathologie , Marqueurs biologiques , Maladie des artères coronaires/diagnostic , Maladie des artères coronaires/métabolisme , Maladie des artères coronaires/physiopathologie , Régime athérogène , Modèles animaux de maladie humaine , Humains , Inflammation/physiopathologie , Lipoprotéines HDL/physiologie , Lipoprotéines LDL/physiologie , Lipoxygenase/métabolisme , Lipoxygenase/physiologie , Souris , Oxydoréduction , Phospholipides/physiologie
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