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61.
Alzheimer disease (AD) and metabolic syndrome are two highly prevalent pathological conditions of Western society due to incorrect diet, lifestyle, and vascular risk factors. Recent data have suggested metabolic syndrome as an independent risk factor for AD and pre-AD syndrome. Furthermore, biological plausibility for this relationship has been framed within the "metabolic cognitive syndrome" concept. Due to the increasing aging of populations, prevalence of AD in Western industrialized countries will rise in the near future. Thus, new knowledge in the area of molecular biology and epigenetics will probably help to make an early molecular diagnosis of dementia. An association between metabolic syndrome and specific single-nucleotide polymorphisms (SNPs) in the gene INPPL1, encoding for SHIP2, a SH2 domain-containing inositol 5-phosphatase involved in insulin signaling, has been described. According to recent data suggesting that Type 2 diabetes represents an independent risk factor for AD and pre-AD, preliminary results of a case-control study performed to test the putative association between three SNPs in the SHIP2 gene and AD show a trend toward association of these SNPs with AD.  相似文献   
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Long-lived individuals (LLIs) are considered an ideal model to study healthy human aging. Blood fatty acid (FA) profile of a cohort of LLIs (90–111 years old, n?=?49) from Sicily was compared to adults (18–64 years old, n?=?69) and older adults (65–89 years old, n?=?54) from the same area. Genetic variants in key enzymes related to FA biosynthesis and metabolism were also genotyped to investigate a potential genetic predisposition in determining the FA profile. Gas chromatography was employed to determine the FA profile, and genotyping was performed using high-resolution melt (HRM) analysis. Blood levels of total polyunsaturated FA (PUFA) and total trans-FA decreased with age, while the levels of saturated FA (SFA) remained unchanged. Interestingly, distinctively higher circulatory levels of monounsaturated FA (MUFA) in LLIs compared to adults and older adults were observed. In addition, among LLIs, rs174537 in the FA desaturase 1/2 (FADS1/2) gene was associated with linoleic acid (LA, 18:2n-6) and docosatetraenoic acid (DTA, 22:4n-6) levels, and the rs953413 in the elongase of very long FA 2 (ELOVL2) was associated with DTA levels. We further observed that rs174579 and rs174626 genotypes in FADS1/2 significantly affect delta-6 desaturase (D6D) activity. In conclusion, our results suggest that the LLIs have a different FA profile characterized by high MUFA content, which indicates reduced peroxidation while maintaining membrane fluidity.

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64.
Drug Safety - European Union legislation has mandated the submission of European Economic Area non-serious reports to the EudraVigilance database since November 2017. As spontaneous reports of...  相似文献   
65.
The mechanisms of chronic spontaneous urticaria (CSU) continue to be unknown. Our working hypothesis is that polymorphisms of cyclo-oxygenases and 5-lipo-oxygenase-activating protein may be involved in the pathways leading to CSU. We examined five candidate polymorphisms of cyclo-oxygenases 1 and 2 and of 5-lipo-oxygenase-activating protein in 109 controls and in 94 CSU patients from Northern Italy. We also examined the levels of urinary leukotriene E4 (LTE4) before and after challenge with ASA. A multiple regression model was found to show that COX-2 5'UTR T/G, COX-2 Exon 10 T/C, and FLAP -336 G/A polymorphisms were significantly associated with CSU, with the minor allele more represented in CSU group. Similar results were obtained as regards the specific association with ASA-tolerated CSU and ASA-exacerbated CSU. Evaluating a polygenic model, reflecting the sum of the concomitant alleles associated with CSU (i.e. COX-2 5'UTR G allele, COX-2 Exon 10?C allele, and FLAP -336 G/A allele), the proportion of CSU patients increased progressively with the increasing number of unfavourable alleles. Finally, in a linear regression model after adjustment for disease status COX-1 22 T carriership remained a significant predictor of post-challenge high urinary LTE4 levels. Our results support the hypothesis that polymorphisms of cyclo-oxygenases and 5-lipo-oxygenase-activating protein may be associated with CSU.  相似文献   
66.
Killer immunoglobulin‐like receptors (KIRs) regulate the activation of natural killer cells through their interaction with human leucocyte antigens (HLA). KIR and HLA loci are highly polymorphic, and certain HLA‐KIR combinations have been found to protect against viral infections. In this study, we analysed whether the KIR/HLA repertoire may influence the course of hepatitis B virus (HBV) infection. Fifty‐seven subjects with chronic hepatitis B (CHB), 44 subjects with resolved HBV infection and 60 healthy uninfected controls (HC) were genotyped for KIR and their HLA ligands. The frequency of the HLA‐A‐Bw4 ligand group was higher in CHB (58%) than subjects with resolved infection (23%) (crude OR, 4.67; P<.001) and HC (10%) (crude OR, 12.38; P<.001). Similar results were obtained for the HLA‐C2 ligand group, more frequent in CHB (84%), than subjects with resolved infection (70%) (crude OR, 2.24; P<.10) and HC (60%) (crude OR, 3.56; P<.01). Conversely, the frequency of KIR2DL3 was lower in CHB (81%) than in subjects with resolved infection (98%) (crude OR, 0.10; P<.05). These results suggest a detrimental role of HLA‐A‐Bw4 and HLA‐C2 groups, which are associated with the development of CHB, and a protective role of KIR2DL3. A stepwise variable selection procedure, based on multiple logistic regression analysis, identified these three predictive variables as the most relevant, featuring high specificity (90.9%) and positive predictive value (87.5%) for the development of CHB. Our results suggest that a combination of KIR/HLA gene/alleles is able to predict the outcome of HBV infection.  相似文献   
67.
The T cell branch of the immune system has been extensively studied in the elderly and it is known that the elderly have impaired immune function, mainly due to the chronic antigenic load that ultimately causes shrinkage of the T cell repertoire and filling of the immunologic space with memory T cells. In the present paper, we describe the IgDCD27 double-negative B cell population which (as we have recently described) is higher in the elderly. Most of these cells were IgG+. Evaluation of the telomere length and expression of the ABCB1 transporter and anti-apoptotic molecule, Bcl2, shows that they have the markers of memory B cells. We also show that these cells do not act as antigen presenting cells, as indicated by the low levels of CD80 and DR, nor do they express significant levels of the CD40 molecule necessary to interact with T lymphocytes through the ligand, CD154. Hence, we hypothesize that these expanded cells are late memory or exhausted cells that have down-modulated the expression of CD27 and filled the immunologic space in the elderly. These cells might be the age-related manifestation of time-enduring stimulation or dysregulation of the immune system.  相似文献   
68.
Pro-inflammatory cytokines and acute-phase proteins play an important role in Alzheimer's disease (AD) neurodegeneration, and common polymorphisms of genes controlling their production have been shown to be associated with AD. Tumor necrosis factor (TNF)-alpha is an inflammatory cytokine involved in the local immune response occurring in the central nervous system of AD patients. Genetic variation could contribute to the risk of developing AD or influence the age at the onset of the disease. We genotyped 222 patients (152 women, 70 men; age range 60-87) and 240 non-demented age-matched healthy controls for TNF-alpha -308 G/A single nucleotide polymorphism (SNP). No significant differences were observed in genotyped frequencies between patients and controls, whereas carriers of -308A showed a significantly lower mean age at onset than non-carriers of this allele. This difference was more evident taking into account ApolipoproteinE (ApoE) status since the lowest age at onset was observed in patients carrying the -308ATNF+/APOE4+ genotypes. In conclusion, our data support previous suggestions that, at least in Caucasians, the TNF gene is a disease modifier gene in patients in which AD is rising, bringing to light the importance of genetic variation at the pro-inflammatory components in the progression of AD.  相似文献   
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Antiphospholipid antibodies (APA) are known to be associated with a number of seemingly heterogeneous pathological conditions that are part of the antiphospholipid syndrome, formerly called anticardiolipin syndrome. Recent studies on the mechanism of action of these autoantibodies suggest that we are dealing with a new autoimmune syndrome which may occur either in a primary form or in the context of other autoimmune diseases, mainly systemic lupus erythematosus (SLE). Moreover, increased levels of APA have been found in elderly subjects, who are known to display increased frequency of autoimmune phenomena. It is well known that many autoimmune diseases, including SLE, are associated with HLA antigens, particularly with HLA-B8,DR3 phenotype. In our study, APA serum levels were analyzed in 26 old subjects and in 56 young ones. The results demonstrate that HLA-B8,DR3-positive young females display significantly higher levels of APA than HLA-B8,DR3-negative ones. Interestingly, the same is true for elderly subjects on the whole with respect to young individuals. These data are consistent with previous findings demonstrating that HLA-B8,DR3-positive subjects (mainly female) as well as old subjects display (also in the absence of any clinical manifestation), multiple immune dysfunctions that may underlie the predisposition to autoimmunity.  相似文献   
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