1,720,964 research outputs found
Bombesin enhances monocyte and macrophage activities: possible role in the modulation of local pulmonary defenses in chronic bronchitis
No full textIncreased lung levels of bombesin-related peptides (BRPs) have been described in smokers and in patients with chronic obstructive pulmonary diseases (COPDs). Moreover, previous studies have shown that BRPs are endowed with immunoregulatory activities. The aim of the present study was to assess the in vitro influence of synthetic bombesin on the activity of mononuclear phagocytes obtained from healthy donors and from COPD patients. Bombesin significantly enhanced in vitro phagocytosis of monocytes and alveolar macrophages in both groups of subjects, restoring deficient phagocytosis in a group of COPD patients. Moreover, bombesin stimulated superoxide anion production and interleukin-8 release by peripheral monocytes
Effect of beta-lactam antibiotics on migration and bactericidal activity of human phagocytes
No full textBombesin, calcium homeostasis and tumour growth
No full textBombesin and its analogues are a family of naturally occurring neuropeptides with potent mitogenic activity. The ability of this agent to induce Ca2+ transients is likely to be relevant in this context, but it is not yet clear whether the effect of bombesin on cell growth is directly and exclusively related to its capacity to increase cytoplasmic Ca2+ levels. The present study investigates the affect of bombesin on cytoplasmic Ca2+ concentrations in human tumour cells of different origin: lung adenocarcinoma, lung adenocarcinoma with properties of alveolar epithelial cells (A549 cell line), mesothelioma and uterine carcinoma (HeLa cell line). Furthermore, the ability of bombesin to promote the in vitro growth of the same cells has been analysed. This agent was able to induce a transient rise in cytoplasmic Ca2+ levels in tumour cells from all lines. In lung adenocarcinoma cells, but not in the other tumour cells, bombesin produced Ca2+ transients followed by a moderate but sustained elevation of Ca2+ levels. The effects of bombesin on tumour cell cytoplasmic Ca2+ levels were compared to those of other agents, i.e. adenosine diphosphate (ADP), collagen or thrombin, which have been reported to induce Ca2+ transients in tumour cells. Bombesin and ADP increased cytoplasmic Ca2+ levels in all cell lines, while collagen and thrombin gave rise to higher transients, but were effective only in some tumour cells and not in others. Furthermore, bombesin was able to stimulate in vitro growth of all the tumour cells, except for the A549 cells, in which this agent induced a slightly lower increase in cytoplasmic Ca2+ concentration. These data may aid a better understanding of the complex relationship between the Ca2+ mobilizing and mitogenic activities of bombesin and may be of general interest when considering the biological effects of growth-stimulating factors
Bombesin enhances monocyte and macrophage activities: possible role in the modulation of local pulmonary defenses in chronic bronchitis
No full textIncreased lung levels of bombesin-related peptides (BRPs) have been described in smokers and in patients with chronic obstructive pulmonary diseases (COPDs). Moreover, previous studies have shown that BRPs are endowed with immunoregulatory activities. The aim of the present study was to assess the in vitro influence of synthetic bombesin on the activity of mononuclear phagocytes obtained from healthy donors and from COPD patients. Bombesin significantly enhanced in vitro phagocytosis of monocytes and alveolar macrophages in both groups of subjects, restoring deficient phagocytosis in a group of COPD patients. Moreover, bombesin stimulated superoxide anion production and interleukin-8 release by peripheral monocytes
Cefodizime modulates in vitro tumor necrosis factor-alpha, interleukin-6 and interleukin-8 release from human peripheral monocytes
No full textAmong third-generation cephalosporins, cefodizime (CFDZ) has shown to modulate many functions of the host defense system against infections. The aim of the present study was to assess the in vitro CFDZ-dependent modulation of interleukin (IL)-6, tumor necrosis factor-alpha (TNF-alpha) and IL-8 release from lipopolysaccharide (LPS)-stimulated human peripheral mononuclear cells (MNCs). Two other third-generation cephalosporins: ceftriaxone (CFX) and ceftazidime (CFT), were also tested under the same experimental conditions. At concentrations ranging from 200 to 50 micrograms/ml, CFDZ significantly decreased TNF-alpha and IL-6 release from maximally (LPS 1 microgram/ml) stimulated MNCs (42% inhibition of TNF-alpha release with 100 micrograms/ml of CFDZ). On the other hand, CFDZ revealed a marked stimulatory effect on IL-8 release (200 micrograms/ml of CFDZ induced 51.5% enhancement of IL-8 release). On the contrary, both CFX and CFT failed to exert any significant effect on TNF-alpha, IL-6 or IL-8 release
Bombesin, calcium homeostasis and tumour growth
No full textBombesin and its analogues are a family of naturally occurring neuropeptides with potent mitogenic activity. The ability of this agent to induce Ca2+ transients is likely to be relevant in this context, but it is not yet clear whether the effect of bombesin on cell growth is directly and exclusively related to its capacity to increase cytoplasmic Ca2+ levels. The present study investigates the affect of bombesin on cytoplasmic Ca2+ concentrations in human tumour cells of different origin: lung adenocarcinoma, lung adenocarcinoma with properties of alveolar epithelial cells (A549 cell line), mesothelioma and uterine carcinoma (HeLa cell line). Furthermore, the ability of bombesin to promote the in vitro growth of the same cells has been analysed. This agent was able to induce a transient rise in cytoplasmic Ca2+ levels in tumour cells from all lines. In lung adenocarcinoma cells, but not in the other tumour cells, bombesin produced Ca2+ transients followed by a moderate but sustained elevation of Ca2+ levels. The effects of bombesin on tumour cell cytoplasmic Ca2+ levels were compared to those of other agents, i.e. adenosine diphosphate (ADP), collagen or thrombin, which have been reported to induce Ca2+ transients in tumour cells. Bombesin and ADP increased cytoplasmic Ca2+ levels in all cell lines, while collagen and thrombin gave rise to higher transients, but were effective only in some tumour cells and not in others. Furthermore, bombesin was able to stimulate in vitro growth of all the tumour cells, except for the A549 cells, in which this agent induced a slightly lower increase in cytoplasmic Ca2+ concentration. These data may aid a better understanding of the complex relationship between the Ca2+ mobilizing and mitogenic activities of bombesin and may be of general interest when considering the biological effects of growth-stimulating factors
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