Search results for "restriction"
showing 10 items of 527 documents
MHC-restricted T cell receptor signaling is required for αβ TCR replacement of the pre T cell receptor
2008
A developmental block is imposed on CD25(+)CD44(-) thymocytes at the beta-selection checkpoint in the absence of the pre T cell receptor (preTCR) alpha-chain, pTalpha. Early surface expression of a transgenic alphabeta TCR has been shown to partially circumvent this block, such that thymocytes progress to the CD4(+)CD8(+) double-positive stage. We wanted to analyze whether a restricting MHC element is required for alphabeta TCR-expressing double-negative (DN) thymocytes to overcome the developmental block in pTalpha-deficient animals. We used the HY-I knock-in model that endows thymocytes with alphabeta TCR expression in the DN compartment but has the advantage of physiological expression l…
Restrictive pulmonary dysfunction at spirometry and mortality in the elderly
2008
SummaryObjectivesTo evaluate the association between pulmonary restriction and mortality in the elderly, taking into account potential confounders not considered in the past (disability, cognitive dysfunction, diabetes, and visceral obesity).DesignLongitudinal study.SettingCommunity-based.ParticipantsTwelve hundred sixty-five patients (51.9% men) aged 65–97 years old from the Salute Respiratoria nell'Anziano (SaRA) Italian multicentric study.MeasurementsParticipants were divided in 4 groups: normal spirometry (NS): FEV1/FVC≥70%, FVC≥80% of predicted; restrictive ventilatory pattern (RVP): FEV1/FVC≥70%, FVC<80%; obstructive ventilatory pattern (OVP): FEV1/FVC<70%, FVC≥80%, and mixed ventilat…
Fetuin-A serum levels are not correlated to kidney function in long-lived subjects
2012
Objectives: Serum Fetuin A has been identified as an inhibitor of ectopic calcification. It is reduced in subjects with chronic kidney disease (CKD) and it has been proposed as a potential link between CKD and the higher prevalence of arterial calcification observed in these patients. During ageing both the stiffening of arterial wall due to calcification and a decline in kidney function are frequent. The aim of the study is to investigate if Fetuin A serum levels are associated with ageing and with AHSG T256S polymorphism. Moreover, we aim at investigate whether serum Fetuin A is correlated to kidney function in this setting of senescence. Design and Methods: 256 health long-lived subjects…
A 3-week feed restriction after weaning as an alternative to a medicated diet: effects on growth, health, carcass and meat traits of rabbits of two g…
2017
Feed restriction after weaning is widely used in meat rabbit farms to promote health and reduce mortality, but this practice impacts negatively on rabbit growth and slaughter performance. This study compared a 3-week post-weaning feed restriction with ad libitum medicated feeding, evaluating effects on feed intake, growth, health, carcass and meat quality of rabbits of two genotypes: Italian White pure breed and Hycole hybrid×Italian White crossbred. A total of 512 rabbits at 36 days of age, of both sexes and two genotypes, were divided into four homogeneous groups assigned, from 36 to 57 days of age, to different feeding programmes (FP): restricted non-medicated (R-N), ad libitum non-medic…
CD8 T cell-evasive functions of human cytomegalovirus display pervasive MHC allele specificity, complementarity, and cooperativity.
2014
Abstract Immunoevasive proteins (“evasins”) of human CMV (HCMV) modulate stability and localization of MHC class I (MHC I) molecules, and their supply of antigenic peptides. However, it is largely unknown to what extent these evasins interfere with recognition by virus-specific CD8 T cells. We analyzed the recognition of HCMV-infected cells by a panel of CD8 T cells restricted through one of nine different MHC I allotypes. We employed a set of HCMV mutants deleted for three or all four of the MHC I modulatory genes US2, US3, US6, and US11. We found that different HCMV evasins exhibited different allotype-specific patterns of interference with CD8 T cell recognition of infected cells. In con…
Partial Sleep Restriction Activates Immune Response-Related Gene Expression Pathways: Experimental and Epidemiological Studies in Humans
2013
Epidemiological studies have shown that short or insufficient sleep is associated with increased risk for metabolic diseases and mortality. To elucidate mechanisms behind this connection, we aimed to identify genes and pathways affected by experimentally induced, partial sleep restriction and to verify their connection to insufficient sleep at population level. The experimental design simulated sleep restriction during a working week: sleep of healthy men (N = 9) was restricted to 4 h/night for five nights. The control subjects (N = 4) spent 8 h/night in bed. Leukocyte RNA expression was analyzed at baseline, after sleep restriction, and after recovery using whole genome microarrays complem…
Transcriptional profiling of rat white adipose tissue response to 2,3,7,8-tetrachlorodibenzo-ρ-dioxin
2015
Polychlorinated dibenzodioxins are environmental contaminants commonly produced as a by-product of industrial processes. The most potent of these, 2,3,7,8-tetrachlorodibenzo-rho-dioxin (TCDD), is highly lipophilic, leading to bioaccumulation. White adipose tissue (WAT) is a major site for energy storage, and is one of the organs in which TCDD accumulates. In laboratory animals, exposure to TCDD causes numerous metabolic abnormalities, including a wasting syndrome. We therefore investigated the molecular effects of TCDD exposure on WAT by profiling the transcriptomic response of WAT to 100 mu g/kg of TCDD at 1 or 4 days in TCDD-sensitive Long-Evans (Turku/AB; L-E) rats. A comparative analysi…
Major histocompatibility complex (MHC) class III genetics in two Amerindian tribes from southern Brazil: the Kaingang and the Guarani.
1997
Population genetic studies of the major histocompatibility complex (MHC) class III region, comprising C2, BF and C4 phenotypes, and molecular genetic data are rarely available for populations other than Caucasoids. We have investigated three Amerindian populations from Southern Brazil: 131 Kaingang from Ivaí (KIV), 111 Kaingang (KRC) and 100 Guarani (GRC) from Rio das Cobras. Extended MHC haplotypes were derived after standard C2, BF, C4 phenotyping and restriction fragment length polymorphism (RFLP) analysis with TaqI, together with HLA data published previously by segregation analysis. C2 and BF frequencies corresponded to other Amerindian populations. C4B*Q0 frequency was high in the GRC…
Different micrococcal nuclease cleavage patterns characterize transcriptionally active and inactive sea-urchin histone genes.
1986
Micrococcal nuclease (MNase) and DNaseI have made a great contribution to our present understanding of the structural organization of the eucaryotic genome [l - 31. The enhanced sensitivity of active portions of the genome to DNaseI gave, in fact, the first indication of differences in the nucleoproteic arrangement of the transcribed as compared to the silent DNA regions [4]. The use of MNase, as a probe of the chromatin organization of specific genes in the active and inactive state, provided additional evidence for this and further showed that the packing of several coding segments of DNA in a regular array of nucleosomal particles is severely but reversibly affected by the transcriptiona…
TRIB1 constitutes a molecular link between regulation of sleep and lipid metabolism in humans.
2012
Epidemiological studies show association between sleep duration and lipid metabolism. In addition, inactivation of circadian genes induces insulin resistance and hyperlipidemia. We hypothesized that sleep length and lipid metabolism are partially controlled by the same genes. We studied the association of total sleep time (TST) with 60 genetic variants that had previously been associated with lipids. The analyses were performed in a Finnish population-based sample (N = 6334) and replicated in 2189 twins. Finally, RNA expression from mononuclear leucocytes was measured in 10 healthy volunteers before and after sleep restriction. The genetic analysis identified two variants near TRIB1 gene th…