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61.
Tian J Shi J Bailey K Harris JM Pritchard A Lambert JC Chartier-Harlin MC Pickering-Brown SM Lendon CL Mann DM 《Neuroscience letters》2004,354(2):103-106
The impact of the insertion (I)/deletion (D) (I/D) polymorphism in the angiotensin 1-converting enzyme (ACE) gene on the extent of white matter myelin loss (ML) was investigated in four regions of the cerebral cortex in an autopsy-confirmed series of 93 patients with Alzheimer's disease (AD). The possible influence of APO E epsilon4 allele acting in concert with ACE D allele was assessed. The extent of ML did not differ between D/D, I/D and I/I genotype groups when data from all four brain regions were combined. However, separate analysis showed that the frontal and temporal cortex tended to be affected more severely by ML in patients with D/D genotype compared to those with I/D and I/I genotypes. Stratification according to APO E epsilon4 allele revealed a greater overall ML in patients bearing at least one copy of ACE D allele and one APO E epsilon4 allele, especially in individuals homozygous for both. The APO E epsilon4 allele may therefore act synergistically in patients with AD (and other subjects) bearing ACE D/D genotype to increase the risk of ML, perhaps through transient ischaemic episodes consequent upon poor cardiac output associated with coronary atherosclerosis in patients with the APO E epsilon4 allele. 相似文献
62.
The purpose of this study was to determine the relative importance of pre- and postweaning nutrition on body mass, body fat, and feeding efficiency in Long-Evans rats up to a period of 18 weeks following weaning. Female rats were bred and pups were redistributed to form large (14-19 pups), normal (11-13 pups) and small (4 pups) litter groups. Weaned rats were housed as pairs (40 pairs) or singletons (n = 16) and fed either a mixed-fat diet (36.6% fat) or a standard chow diet (13.5% fat). Food intake, body mass, and feeding efficiency were measured at 4, 8, 12, and 18 weeks postweaning. Total body fat and depot fat pad mass were also measured at 18 weeks postweaning. At weaning, pups from small litters were fatter (p less than 0.001), and had a greater mass (p less than 0.03) than pups from large litters. There were no persistent effects of preweaning litter size after covarying for preweaning mass on body mass, and postweaning growth, food intake, feeding efficiency, or body fat accretion. Male rats ingesting the mixed-fat diet had a greater body mass (p less than 0.05), greater body fat accretion (p less than 0.008) and a higher feeding efficiency (p less than 0.001) than their chow-fed counterparts, despite an overall lower energy intake (p less than 0.05). Female rats ingesting the mixed-fat diet had a lower food energy intake (p less than 0.005) and a greater feeding efficiency (p less than 0.001) than chow-fed rats during the early postweaning period, only. Thus, postweaning nutrition may play a more important role in postweaning adult mass and depot fat in freely eating rats than early nutritional experiences. 相似文献
63.
Branchial dysplasia, mental deficiency, club feet, and inguinal herniae: a report of two further cases associated with paucity of interlobular bile ducts. 下载免费PDF全文
J C Lambert M C Saint-Paul F Bastiani V Paquis A M Saunieres 《Journal of medical genetics》1990,27(5):330-332
The observation of two new cases in a previously reported family has brought about a change in the delineation of the syndrome initially defined. To the abnormalities already described (branchial dysplasia, mental deficiency, club feet, inguinal herniae) must be added a paucity of interlobular bile duts; the relationship between this new syndrome and the Alagille syndrome requires reconsideration. 相似文献
64.
Rheumatoid arthritis is a chronic and destructive autoimmune joint disease characterized by inflammation of synovial tissue of unknown aetiology. Studies on TCR genes expressed by infiltrating T cells in synovial tissues have attempted to identify mechanism and specificity of the recruitment. T cell infiltrate in rheumatoid arthritis appears to be an association of a polyclonal non specific infiltrate with dominant clones or clonotypes. T cell repertoire in synovial tissue is biased compared to peripheral blood but no TCR V gene can be identified as commonly over-used. Comparison of motifs found in the CDR3 region of dominant clones from different studies has currently failed to identified a commonly motif. The fact that a number of dominant clones or clonotypes is present in different joints and at different times of the disease suggests a selective expansion of T lymphocytes in rheumatoid arthritis synovial membrane. Further investigations are needed to characterize the specificity of these dominant clonotypes. 相似文献
65.
Sympathetic nerve activity and neurotransmitter release in humans: translation from pathophysiology into clinical practice 总被引:6,自引:0,他引:6
Esler M Lambert G Brunner-La Rocca HP Vaddadi G Kaye D 《Acta physiologica Scandinavica》2003,177(3):275-284
AIM: There has been a revolution in cardiovascular neuroscience in recent years with, in some cases, translation into clinical practice of the knowledge of pathophysiology gained through application of sympathetic nerve recording and catecholamine isotope dilution methodology. OBESITY-RELATED HYPERTENSION: An earlier hypothesis, based on findings in most models, was that weight gain in obesity is due in part to sympathetic nervous underactivity reducing thermogenesis. Microneurography and regional noradrenaline spillover measurements in human obesity have disproven this hypothesis, weakening the case for the use of beta3-adrenergic agonists to stimulate thermogenesis. Sympathetic nerve firing rates in post-ganglionic fibres directed to the skeletal muscle vasculature are increased, as is renal sympathetic tone, with a doubling of the spillover rate of noradrenaline from the kidneys. Given these findings, antiadrenergic antihypertensive drugs may be the preferred agents for obesity-related hypertension, but this has not been adequately tested. ESSENTIAL HYPERTENSION: Whether stress causes high blood pressure, previously hotly debated, has been under recent review by an Australian Government body, the Specialist Medical Review Council. Despite medicolegal implications, the ruling was that stress is one proven cause of hypertension. The judgment was reached after consideration of the epidemiological evidence, but in particular the described neural pathophysiology of essential hypertension: (a) persistent sympathetic nervous stimulation is commonly present, (b) suprabulbar projections of noradrenergic brainstem neurones are activated and (c) adrenaline is released as a cotransmitter in sympathetic nerves. These were taken to be biological markers of stress. CARDIAC FAILURE: At one time, the failing heart was thought to be sympathetically denervated. Longterm administration of inotropic adrenergic agonists, to provide the cardiac catecholamine stimulation thought to be lacking, increased mortality. Noradrenaline isotope dilution methodology subsequently demonstrated that the sympathetic outflow to the heart was preferentially activated, cardiac noradrenaline spillover being increased as much as 50-fold. The level of stimulation of the cardiac sympathetic nerves was the most powerful predictor of death. These observations provide the theoretical foundation for the very successful introduction of beta-adrenergic blockers for treatment of heart failure. 相似文献
66.
Whole-cell recordings of EPSCs and G-protein-activated inwardly rectifying (GIRK) currents were made from cultured hippocampal neurones to determine the effect of long-term agonist treatment on the presynaptic and postsynaptic responses mediated by GABAB receptors (GABAB Rs). GABAB R-mediated presynaptic inhibition was unaffected by agonist (baclofen) treatment for up to 48 h, and was desensitized by about one-half after 96 h. In contrast, GABAB R-mediated GIRK currents were desensitized by a similar amount after only 2 h of agonist treatment. In addition, presynaptic inhibition mediated by A1 adenosine receptors (A1 Rs) was unaffected by prolonged GABAB R activation, whereas A1 R-mediated GIRK currents were desensitized. Desensitization of postsynaptic GABAB R and A1 R responses was blocked by the GABAB R antagonist (1-(S)-3,4-dichlorophenylethyl)amino-2-(S) hydroxypropyl-p-benzyl-phosphonic acid (CGP 55845A), but not by the A1 R antagonist cyclopentyldipropylxanthine (DPCPX). GIRK current amplitude could be partially restored after baclofen treatment by either coapplication of baclofen and adenosine, or intracellular infusion of the non-hydrolysable GTP analog 5'-guanylylimidodiphosphate (Gpp(NH)p). Short-term (4-24 h) baclofen treatment also significantly desensitized the inhibition of postsynaptic voltage-gated calcium channels by activation of GABAB Rs or A1 Rs. These results show that responses mediated by GABAB Rs and A1 Rs desensitize differently in presynaptic and postsynaptic compartments, and demonstrate the heterologous desensitization of postsynaptic A1R responses. 相似文献
67.
68.
Background
Correct diagnosis in psychiatry may be improved by novel diagnostic procedures. Computerized Decision Support Systems (CDSS) are suggested to be able to improve diagnostic procedures, but some studies indicate possible problems. Therefore, it could be important to investigate CDSS systems with regard to their feasibility to improve diagnostic procedures as well as to save time. 相似文献69.
Interleukin-2 induced immune effects in human immunodeficiency virus-infected patients receiving intermittent interleukin-2 immunotherapy 总被引:4,自引:0,他引:4
Kovacs JA Vogel S Metcalf JA Baseler M Stevens R Adelsberger J Lempicki R Hengel RL Sereti I Lambert L Dewar RL Davey RT Walker RE Falloon J Polis MA Masur H Lane HC 《European journal of immunology》2001,31(5):1351-1360
To characterize the immunological effects of intermittent IL-2 therapy, which leads to selective increases in CD4+ T lymphocytes in HIV-infected patients, 11 patients underwent extensive immunological evaluation. While IL-2 induced changes in both CD4+ and CD8+ cell number acutely, only CD4+ cells showed sustained increases following discontinuation of IL-2. Transient increases in expression of the activation markers CD38 and HLA-DR were seen on both CD4+ and CD8+ cells, but CD25 (a chain of the IL-2 receptor) increased exclusively on CD4+ cells. This increase in CD25 expression was sustained for months following discontinuation of IL-2, and was seen in naive as well as memory cells. IL-2 induced cell proliferation, but tachyphylaxis to these proliferative effects developed after 1 week despite continued IL-2 administration. It thus appears that sustained CD25 expression selectively on CD4+ cells is a critical component of the immunological response to IL-2, and that intermittent administration of IL-2 is necessary to overcome the tachyphylaxis to IL-2-induced proliferation. 相似文献
70.
Involvement of tumour necrosis factor and other cytokines in immune-mediated vascular pathology 总被引:6,自引:0,他引:6
G E Grau P F Piguet P Vassalli P H Lambert 《International archives of allergy and applied immunology》1989,88(1-2):34-39
Vascular endothelial cells are actively involved in coagulation and inflammation processes and appear to represent an important element in cell-mediated immune responses. In this paper, the possible role of endothelial cells as a target for immunopathological reactions was analyzed. Experimental neurovascular lesions were studied in a model of cerebral malaria, with particular attention to the role of cytokine interactions in vivo. 相似文献