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排序方式: 共有252条查询结果,搜索用时 15 毫秒
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Resistance of mucoid Pseudomonas aeruginosa to nonopsonic phagocytosis by alveolar macrophages in vitro. 总被引:4,自引:3,他引:4 下载免费PDF全文
A unique, recently described rat alveolar macrophage cell line (NR8383) was used to study the interaction of the pulmonary immune system with a mucoid cystic fibrosis isolate of Pseudomonas aeruginosa (SRM-3), its nonmucoid revertant (SRM-3R), and a non-cystic fibrosis isolate (PAO-1). Strain SRM-3 was cultivated in a chemostat system to allow maintenance of an entirely mucoid population. The alveolar macrophage response to the mucoid and nonmucoid strains of P. aeruginosa was determined by visually quantitating phagocytosis in acridine orange-stained monolayers and measuring the induction of an oxidative burst as indicated by chemiluminescence and H2O2 production. In all experiments, fewer than 2% of the NR8383 cells engulfed the mucoid SRM-3 isolate, while SRM-3R and PAO-1 were phagocytized by 15 and 41%, respectively. Opsonization by normal serum (complement) provided minimal phagocytic enhancement of these strains, whereas specific anti-P. aeruginosa antibody slightly elevated phagocytic responses to strains with nonmucoid phenotypes while providing a sevenfold increase in uptake of SRM-3. Chemiluminescent and H2O2 responses were comparable with the levels of phagocytosis observed, with very little or no response to the mucoid strain SRM-3. The data indicate that the strains with mucoid phenotypes are refractile to ingestion and that studies which describe ingestion of mucoid strains were likely measuring ingestion of revertants. Alginic acid (2 mg/ml) was found to inhibit stimulation of macrophage response to the opsonized and unopsonized nonmucoid strain PAO-1. 相似文献
3.
Embolization with “Ethibloc” of vascular tumors and arteriovenous malformations in the head and neck
Summary Ethibloc has been used almost exclusively until now for embolization of tumors and bleeding vessels in the liver and kidney. Unlike with Gelfoam-particles, there is no recanalization. The resorption occurs so slowly that there is no interference with the necrosis of the embolized tumor. Due to its low viscosity, it passes catheters with thin lumina and fills the capillary bed of the tumor without danger of reaching the venous vessels. In this paper we describe a new technic of percutaneous catheter-embolization with Ethibloc using a coaxial catheter which we believe enhances safety and effectiveness. It has been successfully used in five patients. In the meantime two more patients have been treated successfully.Presented in part at the 17th Annual Meeting of the German Society of Neuroradiology, 9–10 October 1981 in Tübingen, FRG. 相似文献
4.
Osteosarcoma relapse after combined modality therapy: an analysis of unselected patients in the Cooperative Osteosarcoma Study Group (COSS). 总被引:4,自引:0,他引:4
Beate Kempf-Bielack Stefan S Bielack Heribert Jürgens Detlev Branscheid Wolfgang E Berdel G Ulrich Exner Ulrich G?bel Knut Helmke Gernot Jundt Hartmut Kabisch Mathias Kevric Thomas Klingebiel Rainer Kotz Rainer Maas Rudolf Schwarz Michael Semik J?rn Treuner Andreas Zoubek Kurt Winkler 《Journal of clinical oncology》2005,23(3):559-568
PURPOSE: To evaluate the impact of patient, tumor, and treatment-related factors on outcome in unselected patients with recurrent osteosarcoma. PATIENTS AND METHODS: Five hundred seventy-six consecutive patients who had achieved a first complete surgical remission (CR) during combined-modality therapy on neoadjuvant Cooperative Osteosarcoma Study Group (COSS) protocols and then developed recurrent osteosarcoma were analyzed (median time from biopsy to relapse, 1.6 years; range, 0.1 to 14.3 years). There were 501 patients with metastases, 44 with local recurrences, and 31 with both. Metastases involved lungs (469 patients), bones (90 patients), and/or other sites (54 patients). RESULTS: After a median follow-up of 1.2 years for all patients and 4.2 years for survivors, actuarial overall survival (OS) rates at 2, 5, and 10 years were 0.38, 0.23, and 0.18, respectively. Five-year OS was 0.39 for 339 patients with and 0.00 for 229 patients without a second surgical CR (P < .0001). A long time to relapse, a solitary lesion, and, in the case of pulmonary metastases, unilateral disease and the absence of pleural disruption, were of positive prognostic value in uni- and multivariate analyses, as were a second surgical CR and the use of second-line chemotherapy. Radiotherapy was associated with moderately prolonged survival in patients without a second CR. The very limited prognostic differences associated with the use of second-line chemotherapy appeared to be more pronounced with polychemotherapy. CONCLUSION: Time to relapse and tumor burden correlate with postrelapse outcome in osteosarcoma. Complete surgery is an essential component of curative second-line therapy. Chemotherapy, particularly chemotherapy with more than one agent, may contribute to limited improvements in outcome. 相似文献
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OBJECTIVES: Hyperprolactinaemia has been associated with the active phase of human systemic lupus erythematosus and rheumatoid arthritis. In the present study, we investigated the role of prolactin (PRL) in relation to the number of typical symptoms and serum markers of systemic inflammation in patients with polymyalgia rheumatica (PMR). METHODS: One hundred and two PMR patients presented with typical symptoms such as adynamia, bilateral muscular pain in shoulders, upper arms or neck, bilateral muscular pain in the pelvic girdle, headache, morning stiffness, arthralgia, symptoms of depression, fever, initial weight loss (>4 kg/month), and transient visual symptoms. If one of the mentioned symptoms was present, the corresponding item was scored with one point (maximum unweighted item points=10). PRL, interleukin-2 (IL-2), IL-6, IL-1 receptor antagonist (IL-1ra), tumour necrosis factor (TNF), soluble IL-2 receptor (sIL-2R), and soluble vascular cell adhesion molecule (sVCAM) were measured by enzyme-linked immunosorbent assay in patients and 31 age-matched healthy controls. RESULTS: Fifteen PMR patients with elevated PRL had a higher number of symptoms as compared with patients with normal levels (P=0.003). PRL was correlated with the number of symptoms (all PMR patients: r(rank)=+0.380, P<0.001) and duration of morning stiffness (all PMR patients: r(rank)=+0.335, P=0.002) irrespective of prior corticosteroid treatment. However, PRL did not correlate with markers of systemic inflammation such as erythrocyte sedimentation rate, C-reactive protein, serum IL-1ra, IL-2, sIL-2R, IL-6, TNF, and sVCAM. CONCLUSION: The number of symptoms in PMR patients was positively correlated with PRL, but PRL was not correlated with serum markers of inflammation. This indicates that PRL is not a pro-inflammatory stimulus in patients with PMR. The inter-relationship between PRL and symptoms or duration of morning stiffness may be more a sign of central nervous system involvement, as it can be observed in people with depressed mood or under psychological stress. 相似文献
7.
Straub RH Glück T Cutolo M Georgi J Helmke K Schölmerich J Vaith P Lang B 《Rheumatology (Oxford, England)》2000,39(6):624-631
OBJECTIVES: To determine the correlation between inflammatory cytokines and adrenal hormones in patients with polymyalgia rheumatica (PMR) and to compare the ratio of serum cortisol and androstenedione (ASD) or dehydroepiandrosterone sulphate (DHEAS) in normal subjects with PMR patients. METHODS: In 102 patients with PMR (32 beginning and 70 chronic disease) and 31 age-matched and sex-matched healthy subjects, ASD, cortisol, DHEAS, interleukin-6 (IL-6), and tumour necrosis factor (TNF) were measured by immunometric assays. RESULTS: Serum levels of IL-6 were elevated in patients with PMR as compared with normal subjects (10.0 +/- 1.6 vs 2.1 +/- 0.1 pg/ml, P = 0.01), which was not found for TNF. In PMR patients, serum levels of IL-6 were positively correlated with serum levels of ASD (P < 0.001), cortisol (P < 0.001), and DHEAS (P = 0. 038) irrespective of corticosteroid treatment. Serum levels of cortisol in relation to IL-6 were significantly lower in patients with chronic disease and long-standing corticosteroid administration as compared with patients with recent onset of the disease and without corticosteroid therapy (P < 0.01). CONCLUSIONS: In PMR, as expected, there was an increase in IL-6 serum levels that was associated with elevated serum levels of ASD, DHEAS, and cortisol which was more marked in patients with recent-onset disease and without corticosteroids. However, serum levels of cortisol in patients with and without corticosteroids were lower than expected by considering the inflammatory status (increased IL-6). This may indicate a change in the hypothalamic-pituitary-adrenal (HPA) axis responsiveness to inflammatory stimuli such as IL-6 during chronic disease. Furthermore, there seems to be a shift of biosynthesis to cortisol in relation to DHEAS or ASD in chronic disease. 相似文献
8.
Sirish Vullaganti Jeff Goldsmith Sergio Teruy Julissa Alvarez Stephen Helmke Mathew S. Maurer 《老年心脏病学杂志》2014,11(2):100-105
Background Previous data from a recently conducted prospective, single blind randomized clinical trial among community dwelling older patients with heart failure with a preserved ejection fraction (HFPEF) and anemia randomized to treatment with epoetin alfa (erythro-poiesis-stimulating agents, ESA) vs. placebo did not demonstrate significant benefits of therapy regarding left ventricular (LV) structure, functional capacity, or quality of life (QOL). However, several patients randomized to the treatment arm were non-responders with a subop-timal increase in hemoglobin. All patients in the trial also received oral ferrous gluconate, which could have contributed to increases in he-moglobin observed in those receiving placebo. Accordingly, we performed an analysis separating patients into responders vs. non-responders in order to determine if measured improvement in anemia would have any effect on clinical endpoints. Methods A total of 56 patients (age 77 ± 11 years, 68%female) were recruited who had anemia defined as a hemoglobin of≤12 g/dL (average, 10.4 ± 1 g/dL) with HFPEF defined as having NHANES-CHF (National Health And Nutrition Examination Survey:Congestive Heart Failure) criteria score of≥3 and an ejection fraction of&gt;40%(average EF=63%±15%). Patients were randomly allocated to receive either ESA and ferrous gluconate or ferrous gluconate only. In this analysis, a responder was defined as a patient with an increase of 1 g/dL in the first 4 weeks of the trial. Re-sults Nineteen subjects were classified as responders compared to 33 non-responders. While the average hemoglobin increased signifi-cantly at the end of 6 months for responders (1.8 ± 0.3 vs. 0.8 ± 0.2 g/dL, P = 0.004), 50% of the subjects assigned to ESA were non-responders. Left ventricular function including ejection fraction (P=0.32) and end diastolic volume (P=0.59) was unchanged in res-ponders compared to non-responders. Responders also showed no significant improvements in New York Heart Association (NYHA) class, Six Minute Walk Test (6 MWT) and peak VO2. Though QOL improved significantly within each group, there was no difference between the two. Conclusions A significant hemoglobin response to anemia treatment with ESA and oral iron does not lead to differences in LV re-modeling, functional status, or QOL. Additionally, a significant percent of older adults with HFPEF and anemia do not respond to ESA ther-apy. Given the results of this small trial, it appears as though using objective improvements in anemia as a marker in older adult subjects with HFPEF does not have significant clinical utility. 相似文献
9.
The objective of this paper is to investigate the association between patterns of anti-dsDNA antibody isotypes and specific clinical manifestations (categorized in renal, musculoskeletal, cutaneous, hematological, pulmonary, neurological and cardiac). Sera of 202 systemic lupus erythematosus (SLE) patients, 33 patients suffering from other autoimmune diseases and 115 healthy blood donors were analysed for anti-dsDNA antibodies by IgG-, IgA- and IgM-specific ELISA, Farr-assay and CLIF. A subset of 24 SLE patients was investigated in a longitudinal study over a period of one to six years. Disease activity of 105 SLE patients was measured according to the ECLAM score. In the cohort of SLE patients 63% were positive for the IgG class, 40% for the IgA and 57% for the IgM class specific anti-dsDNA ELISA. Sensitivity (79%) and specificity (99%) for the diagnosis of SLE appeared to be highest for the ELISA measuring all isotypes of anti-dsDNA antibodies. The concentrations of anti-dsDNA isotypes showed a strong correlation with disease activity. Analysing the relationship between IgG, IgA and IgM anti-dsDNA antibody isotypes and clinical manifestation, we found a significant association of the IgM isotype with cutaneous involvement and of the IgG isotype with lupus nephritis. The IgG/IgM ratio of anti-dsDNA antibodies represented a significant parameter to distinguish patients with lupus nephritis from those without renal involvement. In the longitudinal study, a continuous ratio under 0.8 was associated with absence of renal involvement throughout the investigated period. In conclusion, the evaluation of anti-dsDNA isotypes provides a diagnostic tool to define subsets within SLE patients with different clinical manifestations. In particular, the IgG/IgM ratio of anti-dsDNA antibodies could be used as a prognostic marker for lupus nephritis during the course of the disease. 相似文献
10.
Lawrence Huang Pattie S. Mathieu Brian P. Helmke 《Annals of biomedical engineering》2010,38(5):1728-1740
Several custom-built and commercially available devices are available to investigate cellular responses to substrate strain.
However, analysis of structural dynamics by microscopy in living cells during stretch is not readily feasible. We describe
a novel stretch device optimized for high-resolution live-cell imaging. The unit assembles onto standard inverted microscopes
and applies constant magnitude or cyclic stretch at physiological magnitudes to cultured cells on elastic membranes. Interchangeable
modular indenters enable delivery of equibiaxial and uniaxial stretch profiles. Strain analysis performed by tracking fluorescent
microspheres adhered onto the substrate demonstrated reproducible application of stretch profiles. In endothelial cells transiently
expressing enhanced green fluorescent protein (EGFP)-vimentin and paxillin-DsRed2 and subjected to constant magnitude equibiaxial
stretch, the two-dimensional strain tensor demonstrated efficient transmission through the extracellular matrix and focal
adhesions. Decreased transmission to the intermediate filament network was measured, and a heterogeneous spatial distribution
of maximum stretch magnitude revealed discrete sites of strain focusing. Spatial correlation of vimentin and paxillin displacement
vectors provided an estimate of the extent of mechanical coupling between the structures. Interestingly, switching the spatial
profile of substrate strain reveals that actin-mediated edge ruffling is not desensitized to repeated mechanostimulation.
These initial observations show that the stretch device is compatible with live-cell microscopy and is a novel tool for measuring
dynamic structural remodeling under mechanical strain. 相似文献