排序方式: 共有4条查询结果,搜索用时 390 毫秒
1
1.
Premavathy Rajagopalan-Levasseur Eric Dournon Jean-Louis Vilde Jean-Jacques Pocidalo 《Luminescence》1992,7(2):109-116
Two strains of Legionella pneumophila of different virulence were examined for their influence on the metabolic oxidative activity of human polymorphonuclear leukocytes. The leukocytes exhibited decreased rates of oxygen consumption and diminished chemiluminescence activity following phagocytosis of a virulent strain of L. pneumophila serogroup 1. In contrast, phagocytosis of its multipassaged derivative rendered avirulent, was accompanied by increased rates of both oxygen consumption and chemiluminescence activity. Although no differences were observed in oxygen uptake induced by the virulent legionellae compared to leukocytes at rest, statistically significant differences were observed in the chemiluminescence responses. These observations were not unexpected, since the luminol-enhanced chemiluminescence assay, is more sensitive than the oxygen uptake assay. In spite of decreased metabolic activity of PMN in the presence of virulent legionellae, electron microscope studies showed higher numbers of intracellular L. pneumophila than the avirulent subtype. Thus, virulent and avirulent L. pneumophila can be differentiated on the basis of oxygen consumption and chemiluminescence assays. 相似文献
2.
A. N. Malaviya Naresh K. Gupta Premavathy Rajagopalan R. Kumar 《Journal of biosciences》1982,4(4):481-489
The sera of 36 normal controls, 45 patients with various diseases and 11 pregnant women were screened for circulating immune
complexes using three relatively simple and inexpensive techniques. These included inhibition of agglutination of IgG coated
latex particles with a serum having rheumatoid factor activity, polyethylene glycol precipitation and anti-complementary activity
test. The circulating immune complexes were detected in a significantly higher proportion of patients as compared to normal
controls. In the patients, the presence of circulating immune complexes did not always correlate with clinically detectable
immunoinflammatory tissue damage indicating that pathogenic as well as nonpathogenic immune complexes were being detected
by the above mentioned techniques. The alpha-1-antitrypsin/C3 ratio, however, correlated well with clinically apparent immuno-inflammation. 相似文献
3.
4.
Elbim C Rajagopalan-Levasseur P Chollet-Martin S Gaillard JL Fay M Hakim J Fischer A Casanova JL Gougerot-Pocidalo MA 《Microbes and infection / Institut Pasteur》1999,1(8):581-587
Human phagocytes (polymorphonuclear neutrophils and monocytes) play a critical role in host defense against invading microorganisms. Recent studies reported that circulating phagocytes undergo a final maturation process, in particular in terms of oxidative burst, during extravasation and migration to local sites of inflammation. This process is known as priming. We report here on a nine-year-old boy with successive disseminated infections due to intracellular microorganisms (Mycobacterium bovis, BCG, and Salmonella typhimurium). No T- or B-cell quantitative or qualitative defects were found. Polymorphonuclear neutrophil (PMN) migration and NADPH oxidase in PMNs and monocytes stimulated with various agents at optimal concentrations were normal, ruling out a leukocyte adhesion deficiency syndrome, a Chediak Higashi syndrome, and a chronic granulomatous disease. Nevertheless, the patient's PMNs and monocytes showed defective priming capacity, as measured by H(2)O(2) production after pretreatment with LPS (5 microg/mL for 30 min), TNFalpha (100 units/mL for 30 min), or IL-8 (50 ng/mL for 30 min) in response to bacterial N-formyl peptides (fMLP 10(-6) M for 5 min). In these conditions, H(2)O(2) production of PMNs and monocytes from the patient did not exceed that of the samples treated with fMLP or LPS alone, while the controls strongly produced H(2)O(2). Moreover, monocytes from the patient showed an impaired capacity to kill S. typhimurium in vitro. Such an impairment could be related at least in part to the priming deficiency of phagocyte oxidative burst. This case suggests, for the first time, that in vivo priming processes are critical in host defence against intracellular pathogens. 相似文献
1