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31.
Barry W McColl Ailsa L McGregor Andrew Wong Julian D Harris Andrea Amalfitano Sandra Magnoni Andrew H Baker George Dickson Karen Horsburgh 《Journal of cerebral blood flow and metabolism》2007,27(3):477-487
Apolipoprotein E (apoE, protein; APOE, gene) is the major lipid-transport protein in the brain and plays an important role in modulating the outcome and regenerative processes after acute brain injury. The aim of the present study was to determine if gene transfer of the epsilon3 form of APOE improves outcome in a murine model of transient focal cerebral ischaemia. Mice received an intrastriatal injection of vehicle, a second-generation adenoviral vector containing the green fluorescent protein gene (Ad-GFP) or a vector containing the APOE epsilon3 gene (Ad-APOE) 3 days before 60 mins focal ischaemia. Green fluorescent protein expression was observed in cells throughout the striatum and subcortical white matter indicating successful gene transfer and expression. ApoE levels in the brain were significantly increased after Ad-APOE compared with Ad-GFP or vehicle treatment. Ad-APOE treatment reduced the volume of ischaemic damage by 50% compared with Ad-GFP or vehicle treatment (13+/-3 versus 29+/-4 versus 27+/-5 mm(3)). The extent of postischaemic apoE immunoreactivity was enhanced in Ad-APOE compared with Ad-GFP or vehicle treated mice. These results show the ability of APOE gene transfer to markedly improve outcome after cerebral ischaemia and suggest that modulating apoE levels may be a potential strategy in human stroke therapy. 相似文献
32.
Modulation of the expression of P-glycoprotein, a plasma membrane protein associated with multidrug resistance, was examined in drug-sensitive and drug-resistant tumor cells treated with leukoregulin, a M(r) 50,000 cytokine from human lymphocytes that rapidly permeabilizes the plasma membrane of many tumor cells facilitating the uptake of doxorubicin and other tumor-inhibitory antibiotics. P-glycoprotein expression was measured flow cytometrically by the binding of C219 or MRK16 monoclonal antibody to multidrug-sensitive human K562 erythroleukemia and 8226/S myeloma cells, compared to multidrug-resistant 8226/DOX40 myeloma cells. Cells were treated for up to 2 h with up to 80 units of leukoregulin/ml or one of a variety of unrelated cytokines including interleukin 1 alpha (IL-1 alpha), IL-1 beta, IL-2, IL-3, IL-4, IL-5, IL-6, colony-stimulating factor, macrophage colony-stimulating factor, granulocyte macrophage colony-stimulating factor, tumor necrosis factor alpha, gamma-interferon, alpha-interferon, epidermal growth factor, platelet-derived growth factor AA, platelet-derived growth factor BB, insulin-like growth factor I, insulin-like growth factor II, fibroblast growth factor, or transforming growth factor beta. Leukoregulin caused a concentration-dependent decrease in P-glycoprotein expression; however, P-glycoprotein expression was unaffected by the other cytokines (< 12% decrease in expression). Leukoregulin-induced membrane permeabilization, determined flow cytometrically by intracellular fluorescein efflux, and decreased P-glycoprotein expression occurred simultaneously within 15 min in drug-sensitive and -resistant cells. Enhanced doxorubicin uptake, measured flow cytometrically by doxorubicin influx, was also present within 15 min. Leukoregulin enhancement of doxorubicin uptake and increased membrane permeability varied directly with the decrease in P-glycoprotein expression. Leukoregulin in combination with doxorubicin enhanced the inhibition of cell proliferation in 8226/DOX40 multidrug-resistant cells over expressing P-glycoprotein. In contrast, combined treatment of HL-60/MX2 multidrug-resistant human promyelocytic leukemia cells that do not overexpress P-glycoprotein in association with their multidrug resistance resulted in no greater growth inhibition than observed with HL-60/MX2 cells treated with doxorubicin alone. This is the first demonstration that a naturally occurring macromolecule with anticancer activities can modulate the expression of P-glycoprotein concomitant with enhanced drug uptake and inhibition of cell proliferation. 相似文献
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Background While parenting behaviours have direct effects on children’s behavioural outcomes, other, more distal factors also may be shaping the way a mother handles parenting responsibilities. Dispositional factors are likely to be a major influence in determining how one parents. Although researchers have studied the relationships among maternal dispositional factors, parenting, and child behaviours, few studies have examined these relationships when the child is at developmental risk. Children with developmental delays evidence elevated clinical level behaviour problems, so this group is of primary interest in the search for precursors to psychopathology. The present study examined how the maternal dispositional trait of self‐mastery, as well as supportive and non‐supportive parenting, relate to behaviour problems in young children with and without developmental delay. Method Participants were 225 families, drawn from Central Pennsylvania and Southern California. The children, all aged 4 years, were classified as delayed (n = 97) or non‐delayed (n = 128). The Self‐Mastery Scale measured perceived level of control over life events. The Coping with Children’s Negative Emotions Scale measured different ways parents perceive themselves as reacting to their children’s distress and negative affect. The Child Behavior Checklist assessed children’s behaviour problems. Results Delayed condition mothers reported significantly more child behaviour problems than non‐delayed condition mothers; the two conditions did not differ in self‐mastery, supportive parenting, or non‐supportive parenting. Self‐mastery, non‐ supportive parenting reactions, and child behaviour problems all related significantly to one another. For the sample as a whole and within the delayed condition, the association between self‐mastery and child behaviour problems was partially mediated by non‐supportive parenting reactions, although self‐mastery was still significantly associated with problem behaviour. In the non‐delayed condition, although significant relationships also were found among the variables of interest, non‐supportive parenting did not have a significant main or mediation effect. Delay status moderated the relationship between negative parenting reactions and child behaviour problems, assessed by the Child Behavior Checklist Total and Internalizing scores. When mothers displayed low levels of non‐supportive reactions, children in the delayed and non‐delayed groups had similar levels of total problem behaviour. However, when mothers were medium or high in non‐supportive reactions, children in the delayed group had much higher levels of problem behaviours than those in the non‐delayed group. Conclusions The present study extended research on parental dispositional factors and parenting by measuring self‐mastery as a global personality trait rather than measuring self‐efficacy related specifically to childrearing. Moreover, relationships were examined for both developmentally delayed and non‐delayed samples, allowing for a clearer understanding of the influences on problem behaviours in children with developmental delays. The findings support the view that parenting behaviours have a greater impact on children at developmental risk. 相似文献
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This article attempts to provide a practical template for the psychologic assessment of chronic pain and disability. Topics discussed include differential diagnosis, goals of psychosocial assessment, psychologic constructs, personality issues, pain-drawing ratings, and multidimensional assessment instruments. Other factors affecting psychologic assessment, such as litigation, perception of disability, pain behavior, and cultural factors are also discussed. 相似文献
38.
J E Comaty P G Janicak J Rajaratnam R P Sharma D Baker J M Davis 《Psychopharmacology bulletin》1990,26(2):267-270
The authors designed a three-phase prospective trial in which only those patients who developed an acute, neuroleptic-induced extrapyramidal side effect (EPSE) received benztropine (BZ) at 2 mg i.m. and then 1 mg p.o. b.i.d. for 2 days after their symptoms were rated for severity and type (Preparatory Phase 1). They were then randomly assigned under double-blind conditions to continue BZ or be switched to placebo for 8 days (Experimental Phase 2). Finally in Phase 3 (Followup), all patients continued on placebo in a single-blind design until Day 30. If the patient re-experienced an acute EPSE that was of sufficient severity to require immediate BZ administration, he or she was rated, treated, and then dropped from the study. EPSE scores and dropout rates did not differ in Phase 2 between the placebo- and BZ-treated groups. Implications for the continuation, cessation, or intermittent use of antiparkinsonian (AP) drugs are discussed. 相似文献
39.
The effect of solvent conditions on the aggregation of IgM in serum specimens from patients with macroglobulinemia was studied by a turbidimetric procedure. Aggregation of IgM varied considerably among the samples and was affected by a number of experimental parameters. In general, IgM aggregation was more pronounced under acidic conditions and in solvents with low ionic strength. The presence of water-miscible organic solvents also promoted aggregation. Based on these studies, it was concluded that the major force involved in the formation of immunoglobulin aggregates in the serum of patients with macroglobulinemia was electrostatic, rather than hydrophobic, interactions. A number of additives known to prevent protein aggregation were evaluated for their effectiveness in inhibiting IgM aggregation. The only additives that were shown to inhibit or reduce IgM aggregation were charged molecules, such as arginine, sodium chloride, ethylenediamintetraacetic acid and quaternary ammonium beta-cyclodextrin. Some of these charged additives were also effective in dissociating the IgM aggregates once they were formed, even in the presence of detergent. 相似文献
40.
Administration of high-dose chemotherapy to patients with myeloma, followed by rescue with autologous bone marrow transplantation (ABMT), sometimes induces complete disease remission but relapse is usual. We have attempted to reduce the risk of relapse by selective in vitro removal of myeloma cells from the autologous graft. A combination of the (gal-galNac)-binding lectin peanut agglutinin (PNA), which binds all plasma cells, and the pan-B monoclonal antibody CD19 was assessed for purging marrow of myeloma cells and their putative precursors using a magnetic bead method. Preliminary experiments performed on peripheral blood mononuclear cells spiked with fluorescent-labeled PNA+ Kirk tumor cells showed that a magnetic bead: target cell ratio of 40:1 resulted in a greater than 3-log reduction in PNA+ cells. This technique was then applied to 17 samples of myeloma bone marrow and to 18 samples of normal bone marrow spiked with PNA+ Kirk cells and CD19+ hairy cell leukemia cells. In each case all detectable plasma cells and CD19+ lymphocytes were effectively removed, and normal hemopoietic progenitor cell recovery was greater than 55%. This purging system deserves further study as a means of reducing relapse rates in myeloma patients treated by a combination of high-dose chemotherapy and ABMT. 相似文献