The release of mediators from mast cells is a model for cell secretion and is an in-vitro index for immediate hypersensitivity reactions. Calcium influx is generally accepted to be the primary biochemicalevent in mast...The release of mediators from mast cells is a model for cell secretion and is an in-vitro index for immediate hypersensitivity reactions. Calcium influx is generally accepted to be the primary biochemicalevent in mast cell activation.We studied the effect of the calcium ionophore A 23187 and calcium channelblockers,nifedipine and verapamil, in triggering the activation of rat peritoneal mast cells.At suitableconcentration nifedipine and verapamil have had the inhibition effect in the IgE-dependent roaction.展开更多
Both calcium ionophore A23187 and endoplasmic reticulum Ca2+- ATPase inhibitor thapsigargin (Tg) could increase intracellular free calcium concentration and induce apoptosis in some cell lines. In the present study, w...Both calcium ionophore A23187 and endoplasmic reticulum Ca2+- ATPase inhibitor thapsigargin (Tg) could increase intracellular free calcium concentration and induce apoptosis in some cell lines. In the present study, we found that HL-60 cells treated with A23187 (1μg/ml) for 4 h or with Tg (0.5μg/ml) for 2 h showed typical characteristics of apoptosis. Pretreatment with nontoxic concentration of cyclosporin A (CsA) (1μg/ml) Could block these effects. Flow cytometric analysis of intracellular Ca2+ after staining with fluo-3 AM showed that CsA did not prevent the increase of intracellular calcium induced by A23187 or Tg, but it could maintain the high level of intracellular Ca2+ for a long time. These results suggest that CsA may prevent calcium- induced apoptosis by blocking the transportation of Ca2+ in HL-60cells.展开更多
Objective: To study the role of apoptosis in tumor cell of malignant glioma death following treatment with hyperthermia and calcium ionophore. Methods: The apoptosis induced by hyperthermia and calcium ionophore, A231...Objective: To study the role of apoptosis in tumor cell of malignant glioma death following treatment with hyperthermia and calcium ionophore. Methods: The apoptosis induced by hyperthermia and calcium ionophore, A23187, in human glioblastoma cell line TJ905 and murine glioblastoma G422 was evaluated by characteristic findings in DNA agarose gel electrophresis, ultrastructural examination and flow cytometric analysis. Results: Apoptosis could be induced by moderate hyperthermia, but not by mild hyperthermia, calcium ionophore enhanced significantly the effect of mild hyperthermia on the induction of apoptosis. Conclusion: This result indicates that apoptotic cell death is one of the mechanisms of hyperthermic therapy for malignant glioma and taking measures to increase the cytolic calcium may enhance the effect of hyperthermia.展开更多
Total or near-total fertilization failure after intracytoplasmic sperm injection （ICSl） is a rare event, but it occurs repeatedly because of sperm defects in activating oocyte. The case presents a successful pregnan...Total or near-total fertilization failure after intracytoplasmic sperm injection （ICSl） is a rare event, but it occurs repeatedly because of sperm defects in activating oocyte. The case presents a successful pregnancy and live birth after calcium ionophore A23187 （A23187） activation on one-day-old unfertilized oocytes in a patient whose husband suffered oligoasthenoteratozoospermia, and who had experienced repeated near-total fertilization failure after ICSI. In the second ICSI cycle, only one oocyte was fertilized while nine were unfertilized. Oocyte activation with A23187 were performed on the one-day-old unfertilized oocytes after ICSI and resulted in fertilization and embryo transfer. A clinical pregnancy was achieved and a healthy baby was born. To our knowledge, this is the first reported case of a healthy birth after oocyte activation on the one-day-old unfertilized oocyte. This indicates that ＂rescue oocyte activation＂ on one-day-old unfertilized oocytes after ICSI may be helpful for preventing total or near-total fertilization failure after ICSI.展开更多
The combination of intracytoplasmic sperm injection （ICSI） with artificial oocyte activation has overcome repeated fertilization failure after ICSI due to sperm defects in activating oocyte, resulting in pregnancies...The combination of intracytoplasmic sperm injection （ICSI） with artificial oocyte activation has overcome repeated fertilization failure after ICSI due to sperm defects in activating oocyte, resulting in pregnancies and births for many couples. However, in comparison to the growing data illustrating the effectiveness of artificial oocyte activation in reproductive medicine, the safety of this approach has not been well studied. Previously,展开更多
文摘The release of mediators from mast cells is a model for cell secretion and is an in-vitro index for immediate hypersensitivity reactions. Calcium influx is generally accepted to be the primary biochemicalevent in mast cell activation.We studied the effect of the calcium ionophore A 23187 and calcium channelblockers,nifedipine and verapamil, in triggering the activation of rat peritoneal mast cells.At suitableconcentration nifedipine and verapamil have had the inhibition effect in the IgE-dependent roaction.
文摘Both calcium ionophore A23187 and endoplasmic reticulum Ca2+- ATPase inhibitor thapsigargin (Tg) could increase intracellular free calcium concentration and induce apoptosis in some cell lines. In the present study, we found that HL-60 cells treated with A23187 (1μg/ml) for 4 h or with Tg (0.5μg/ml) for 2 h showed typical characteristics of apoptosis. Pretreatment with nontoxic concentration of cyclosporin A (CsA) (1μg/ml) Could block these effects. Flow cytometric analysis of intracellular Ca2+ after staining with fluo-3 AM showed that CsA did not prevent the increase of intracellular calcium induced by A23187 or Tg, but it could maintain the high level of intracellular Ca2+ for a long time. These results suggest that CsA may prevent calcium- induced apoptosis by blocking the transportation of Ca2+ in HL-60cells.
文摘Objective: To study the role of apoptosis in tumor cell of malignant glioma death following treatment with hyperthermia and calcium ionophore. Methods: The apoptosis induced by hyperthermia and calcium ionophore, A23187, in human glioblastoma cell line TJ905 and murine glioblastoma G422 was evaluated by characteristic findings in DNA agarose gel electrophresis, ultrastructural examination and flow cytometric analysis. Results: Apoptosis could be induced by moderate hyperthermia, but not by mild hyperthermia, calcium ionophore enhanced significantly the effect of mild hyperthermia on the induction of apoptosis. Conclusion: This result indicates that apoptotic cell death is one of the mechanisms of hyperthermic therapy for malignant glioma and taking measures to increase the cytolic calcium may enhance the effect of hyperthermia.
文摘Total or near-total fertilization failure after intracytoplasmic sperm injection （ICSl） is a rare event, but it occurs repeatedly because of sperm defects in activating oocyte. The case presents a successful pregnancy and live birth after calcium ionophore A23187 （A23187） activation on one-day-old unfertilized oocytes in a patient whose husband suffered oligoasthenoteratozoospermia, and who had experienced repeated near-total fertilization failure after ICSI. In the second ICSI cycle, only one oocyte was fertilized while nine were unfertilized. Oocyte activation with A23187 were performed on the one-day-old unfertilized oocytes after ICSI and resulted in fertilization and embryo transfer. A clinical pregnancy was achieved and a healthy baby was born. To our knowledge, this is the first reported case of a healthy birth after oocyte activation on the one-day-old unfertilized oocyte. This indicates that ＂rescue oocyte activation＂ on one-day-old unfertilized oocytes after ICSI may be helpful for preventing total or near-total fertilization failure after ICSI.
文摘The combination of intracytoplasmic sperm injection （ICSI） with artificial oocyte activation has overcome repeated fertilization failure after ICSI due to sperm defects in activating oocyte, resulting in pregnancies and births for many couples. However, in comparison to the growing data illustrating the effectiveness of artificial oocyte activation in reproductive medicine, the safety of this approach has not been well studied. Previously,
