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11.
Enhancement of neutrophil function by granulocyte-macrophage colony- stimulating factor involves recruitment of a less responsive subpopulation 总被引:3,自引:0,他引:3
Human granulocyte-macrophage colony-stimulating factor (GM-CSF) enhances numerous functions of mature neutrophils (PMN) including phagocytosis, superoxide responses to chemotaxins, antibody-dependent cellular cytotoxicity, and expression of complement receptors. A central question concerns whether the mechanism of enhancement involves quantitative increases in the response of all cells v subpopulation recruitment. The effects of GM-CSF on individual cell light scatter changes, membrane potential, and oxidant responses induced by the chemoattractant N-formyl-methionyl-leucyl-phenylalanine (FMLP) were assessed by flow cytometry and by scoring individual cells for nitroblue tetrazolium dye (NBT) reduction. GM-CSF produced a dose- and time-dependent shift in forward light scatter that was very similar in character to that seen with FMLP or leukotriene B4 stimulation. Although not capable of depolarizing the cells directly, GM-CSF primed PMNs for enhanced membrane potential responses to FMLP by significantly increasing the proportion of depolarizing cells when compared with diluent-treated controls after a 60-minute incubation at 37 degrees C (79.4% +/- 3.4% v 29.5% +/- 4.7% GM-CSF v diluent, mean +/- SE, P less than .005, n = 11). Subpopulation recruitment by GM-CSF treatment was also demonstrated by the FMLP-elicited NBT test. Taken together, these results indicate that GM-CSF can modulate the function of mature PMN by enhancing the proportion of responsive cells. 相似文献
12.
A non-human primate antiserum was prepared to acute lymphoblastic leukemia of T-cell phenotype (T-ALL) and, after absorptions with normal blood elements, reacted by immunofluorescence and microcytotoxicity to all the T-ALL tested. In addition, the antiserum reacted with cells from about 70% of the common ALL studied and immunoprecipitated the common ALL antigen of 100,000 daltons. However, when the anti-T-ALL serum was absorbed with with lymphoblasts from common ALL, it failed to react with common ALL lymphoblasts, yet reacted significantly with cells from patients with T-ALL phenotype and defined a 100,000-dalton membrane component not found on common ALL lymphoblasts. In addition, sequential immunoprecipitation of 125I-labeled T-ALL membranes by anti- common-ALL serum followed by anti-T-ALL serum detected the T-ALL membrane component of 100,000 daltons that was not found on common ALL. Thus, our results demonstrate the presence of of a unique human T-ALL antigen present on all T-ALL distinct from the common ALL antigen. 相似文献
13.
作为标准化的非手术治疗,诱导化疗(ICT)在治疗局部晚期头颈鳞癌已有几十年的历史,但是关于其作用尚存争议。同期放化疗(CRT)是目前标准化的非手术治疗,然而由于ICT能够使肿瘤体积缩小,提高放疗的可行性,改善患者对放疗的耐受力,增加放疗后器官功能保留的可能性及降低远处转移率。所以,对ICT的研究从未停止。该文对近期随机试验进行回顾分析,与手术或单独CRT比较,评估ICT中紫杉醇的价值。Meta分析比较ICT中紫杉醇和顺铂及5氟尿嘧啶的作用。之前的随机试验中,并没有ICT提高生存率的报道。但 相似文献
14.
Modern population based oral health management requires a complete understanding of the impact of disease in order to provide efficient and effective oral health care and guidance. Periodontitis is an important cause of tooth loss and has been shown to be associated with a number of systemic conditions. The impact of oral conditions and disorders on quality of life has been extensively studied. However, the impact of periodontitis on quality of life has received less attention. This review summarizes the literature on the impact of periodontitis on oral health‐related quality of life (OHRQoL). Relevant publications were identified after searching the MEDLINE and EMBASE electronic databases. Screening of titles and abstracts and data extraction was conducted. Only observational studies were included in this review. Most of the reviewed studies reported a negative impact of periodontitis on OHRQoL. However, the reporting standards varied across studies. Moreover, most of the studies were conducted in developed countries. 相似文献
15.
16.
Lymphocyte migration into the central nervous system is a central event in lesion formation in MS. Both interferon beta (IFNbeta) and copolymer-1 (Cop-1) reduce the overall lymphocyte entry into the brain through the blood-brain barrier (BBB) as judged by MRI based studies. In this study, we used a modified Boyden chamber assay in which human brain microvascular endothelial cell (HBEC) monolayers are grown on a fibronectin coated transwell membrane to evaluate in vitro migration of allo-antigen Th1 and Th2 lymphocytes across brain endothelium. We confirmed previous observations showing that migration rates of Th2 lymphocytes across HBECs were higher than migration rates of Th1 cells. When HBECs were pre-treated with IFNbeta (100 U/ml) 30 min prior to migration, the migration rate of Th1 was significantly decreased (45% reduction) while the migration of Th2 remained unchanged. Addition of Cop-1 (30 microg/ml) to HBEC monolayers 30 min prior to migration significantly increased the migration rate of Th2 cells and did not affect the migration of Th1 cells. We did not observe any changes in (1) the expression of adhesion molecules on the surface of HBECs and (2) the pattern of chemokine production by HBECs after IFNbeta or Cop-1 treatment. The changes in cellular migration rates were not paralleled with changes in diffusion of large molecular weight tracers across brain ECs. Our data support the notion that immuno-modulators used for the treatment of MS selectively and differentially regulate the migration of T helper lymphocyte subsets and that Cop-1 promotes trans-endothelial migration of Th2 cells across the BBB. 相似文献
17.
18.
Over the past decade, the unfortunate reality is that the income gap has widened between Canadian families. Educational outcomes are one of the key areas influenced by family incomes. Children from low-income families often start school already behind their peers who come from more affluent families, as shown in measures of school readiness. The incidence, depth, duration and timing of poverty all influence a child’s educational attainment, along with community characteristics and social networks. However, both Canadian and international interventions have shown that the effects of poverty can be reduced using sustainable interventions. Paediatricians and family doctors have many opportunities to influence readiness for school and educational success in primary care settings. 相似文献
19.
Novero V; Camus M; Tournaye H; Smitz J; Verheyen G; Joris H; Derde MP; Van Steirteghem AC; Devroey P 《Human reproduction (Oxford, England)》1997,12(1):59-63
Serum follicle stimulating hormone (FSH) is routinely measured when
evaluating the infertile male for intracytoplasmic sperm injection (ICSI).
However, among the sperm parameters, only its relationship with sperm
concentration is well documented. Few investigations concern the
relationship between FSH and sperm motility and morphology, and the results
of ICSI. A retrospective study of 316 couples who underwent ICSI was
carried out to determine the relationships between serum FSH concentrations
in the male and (i) standard sperm parameters_(concentration, motility and
morphology) and (ii) fertilization, cleavage, pregnancy and implantation
rates after ICSI. There was an inverse correlation with sperm concentration
and total motility but no relationship was found with progressive motility
and sperm morphology. Neither was any relationship found between serum FSH
and fertilization, cleavage, pregnancy and implantation rates, and the
results of ICSI. These findings suggest the need to review the routine
measurement of serum FSH in the infertile male when ICSI is the planned
treatment procedure.
相似文献
20.
Bhattacharya S; MacLennan F; Hamilton MP; Templeton A 《Human reproduction (Oxford, England)》1997,12(7):1440-1442
Although the conventional method of pain relief during outpatient oocyte
recovery involves physician-administered drugs, patient- controlled
analgesia (PCA) offers an alternative technique with the potential to give
women more control over peroperative analgesia. We conducted a prospective
randomized study to compare the effect of fentanyl administered either
through a PCA delivery system or by a physician. Thirty-nine women were
randomized to PCA during egg collection while 42 were allocated to receive
intermittent doses administered by a physician. Pain was evaluated by means
of a 100 mm linear analogue scale. The mean (SD) pain score in the PCA
group was 38.5 (19.8) while in the other group it was 46.1 (21.3) (P =
0.1). In the PCA group, 64% of women felt very satisfied with their
analgesia as compared with 57% in the non-PCA group (P = 0.6). Among the
PCA users, 39% of demands were successful. Significantly more fentanyl
(97.5 microg) was used in the PCA group than in the other group (84.6
microg) (P = 0.03). Though intraoperative PCA with fentanyl is an effective
alternative to physician-administered techniques, many women still feel the
need for more analgesia during the procedure.
相似文献