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51.
Mycobacteria-infected macrophages are poor responders to interferon-gamma (IFN-gamma), resulting in decreased expression of IFN-gamma-induced genes. In the present study, we examined the inhibition of IFN-gamma-induced gene expression by Mycobacterium tuberculosis and four different Mycobacterium avium strains in mouse RAW264.7 macrophages. Gamma-irradiated M. tuberculosis inhibited mRNA expression of a panel of six different IFN- gamma-induced genes. All four of the M. avium strains completely inhibited IFN-gamma-induced expression of MHC class II Aalpha and Ebeta mRNA. However, the Mac101 strain, which is serovar 1, inhibited IFN-gamma induction of IFN regulatory factor-1 (IRF-1) and guanylate-binding protein-1 (GBP-1) mRNA to a greater extent than the other M. avium strains, which are serovar 2. In this study, we also show that mycobacteria inhibit gene expression by both toll-like receptor 2 (TLR2)-dependent and independent pathways. The inhibition of IFN-gamma-induced gene expression by M. avium was reduced but not completely blocked in macrophages from TLR2(/) mice. IFN-gamma-induced gene expression was also inhibited by mycobacteria in RAW264.7 cells expressing dominantnegative TLR2 or myeloid differentiation factor 88 (MyD88), further indicating the existence of a pathway independent of TLR2 and MyD88. These data suggest that mycobacteria inhibit IFN-gamma-induced gene expression by multiple pathways involving both TLR2 and non-TLR receptors.  相似文献   
52.
Mapping brain size and cortical gray matter changes in elderly depression.   总被引:1,自引:0,他引:1  
BACKGROUND: In elderly depression, volumetric brain imaging findings suggest abnormalities of the frontal lobe, particularly the orbitofrontal cortex, and the hippocampus. No studies to date have mapped cortical abnormalities over the entire brain surface in major depression. Here, we conducted detailed spatial analyses of brain size and gray matter within the cortical mantle in elderly patients with major depression. METHODS: High-resolution, three-dimensional, structural magnetic resonance imaging data and cortical pattern matching methods were used in 24 depressed elderly patients and 19 group-matched controls to measure local brain size and proportions of gray matter at thousands of homologous cortical surface locations. RESULTS: Prominent brain size reductions were observed in the depressed subjects in the orbitofrontal cortex bilaterally. Cortical gray matter measurements revealed significant gray matter increases in the orbitofrontal cortex, adjacent to focal trend level significant decreases of gray matter in the same region. Depressed patients also exhibited significant gray matter increases in parietal cortices, as well as the left temporal cortex. CONCLUSIONS: Complex cortical changes may contribute to the brain size reduction of the orbitofrontal cortex and to the gray matter abnormalities detected in orbitofrontal cortex and temporoparietal cortices, thereby providing a potentially new window into the pathophysiology of elderly depression.  相似文献   
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54.
OBJECTIVE: To examine corticomotoneuronal function in amyotrophic lateral sclerosis (ALS) patients carrying superoxide dismutase 1 (SOD1) mutations using peristimulus time histograms (PSTH). METHODS: Six I113T, 3 A4V, one G41D and one G114A patient were studied along with 21 healthy control subjects. Analyses included comparison with previously reported data from 8 D90A homozygous and 12 sporadic ALS (SALS) patients examined by the authors using identical methodology. RESULTS: Cortical threshold was significantly reduced in A4V patients (41.3%) compared to I113T (58%), SALS (57%) and D90A (71%) patients, as well as healthy controls (49.7%). Estimated excitatory postsynaptic potentials (EPSPs) were significantly larger in A4V patients (4.39 mV) compared to healthy controls (2.95 mV), I113T (2.71 mV) and SALS (2.39 mV) patients. Clinical features and PSTH parameters in I113T were similar to SALS, however, PSTH primary peaks (PP) were significantly more dispersed, 9.5 ms compared to 4ms in SALS. PSTHs from single G41D and G114A patients were unremarkable, apart from large EPSP amplitudes in the G114A patient. CONCLUSIONS: ALS patients with A4V and I113T SOD1 mutations have distinctive corticomotoneuronal changes that are different from those in D90A homozygous and SALS patients. SIGNIFICANCE: PSTH studies should be considered for future in vivo studies of SOD1 pathophysiology in ALS.  相似文献   
55.
Individuals with left-hemisphere damage often have concomitant impairment of spoken and written language. Whereas some treatment studies have shown that reading paired with spoken naming can benefit both language modalities, little systematic research has been directed toward the treatment of spelling combined with spoken naming. The purpose of this study was to examine the therapeutic effect of pairing a lexical spelling treatment referred to as Copy and Recall Treatment (CART) with verbal repetition of target words. This approach (CART + Repetition) was compared with treatment using verbal repetition without the inclusion of orthographic training (Repetition Only). Two individuals with moderate aphasia and severe impairment of spelling participated in the study using a multiple baseline design across stimulus sets and treatment conditions. Both participants improved spelling of targeted words as well as spoken naming of those items, but improvement in spoken naming was marked for one individual in the CART + Repetition condition, while the other participant made smaller gains in spoken than written naming irrespective of treatment condition. Consideration of the participant profiles suggested that CART + Repetition provides greater benefit when there is some residual phonological ability and the treatment serves to stimulate links between orthography and phonology.  相似文献   
56.
Health Care Analysis -  相似文献   
57.
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   
58.
C H Evans  P D Baker 《Cancer research》1992,52(21):5893-5899
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   
59.
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   
60.
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