Enhancing effect of dendritic cells derived from human cord blood on T cells in killing tumor cells / 中国实验血液学杂志

Dendritic cells (DCs) derived from bone marrow cells are specialized cells for the uptake, processing, and presentation of foreign and self-antigens. The study indicated that re-transfusion of DCs pulsed with tumor-associated antigen can induce an vigorous specific anti-tumor response in clinic. The present study was aimed to investigate the enhancing effect of DCs derived from human cord blood on T cells in killing tumor cells. Human cord blood mononuclear cells were isolated from human cord blood by density gradient centrifugation using lymphocyte separating medium, and cord blood mononuclear cells were obtained by adherence and cultured in a liquid culture system with GM-CSF and IL-4 for 15 days. Then the cells were analyzed for phenotypes of CD1a by indirect immunofluorescence. The capacity of DCs to initiate T cell-dependent anti-tumor immune responses was assayed by MTT kit. The ratios of DCs to tumor cells in experimental groups were 20:1, 50:1 and 100:1 respectively. The DCs were not added in control group. The results indicated that in the presence of GM-CSF and IL-4, the DCs with typical morphological features at days 15 were observed. At that time, (43.12 +/- 5.83)% CD1a(+) cells were obtained. In addition to these phenotypic properties, the DC of experimental groups could remarkably initiate T cell-dependent anti-tumor immune responses with different ratios compared with control group (P < 0.01), there were no significant difference of killing effects between 100:1 and 50:1 groups (P > 0.05), and killing effect of DC in 20:1 group was higher than that in 100:1 or 50:1 groups (P < 0.05). It is concluded that human cord blood mononuclear cells can serve as a better source of DC, which can promote the capacity to initiate T cell-dependent anti-tumor immune responses.

The study on freezing intercostal nerves for the relief of postoperative chest pain / 中华外科杂志

<p><b>OBJECTIVE</b>To explore the best freezing time and the optimum analgesia modality.</p><p><b>METHODS</b>In dogs, intercostal nerves were froze at -70 degrees C at different time including 30, 60, 90, 120, 180 s. Samples were got at the operative day, in 10 days and 60 days respectively, then carried on the pathology exam. In clinical study, 150 patients undergoing thoracotomy were randomly designated into 5 groups, all patients were recorded the heart rate, blood pressure, SO2, VAS, the dosage of dolantin, and observed the complications and side effects.</p><p><b>RESULTS</b>At operative day, the freezing nerves appeared brown print macroscopically, and presented degeneration, necrosis of the nerve fiber microscopically with more than 90 s. After 10 days, nerves with more than 90 s became thinner than normal. After 60 days, all nerves had no obvious differentiation than normal. In clinical study, both 90 s group and 90 s with PCIA group were significantly better than 60 s group or PCIA group; The VAS of 90 s with PCIA group was significantly lower than 90 s group but had more side effects such as vomiting, nausea.</p><p><b>CONCLUSIONS</b>At -70 degrees C, the freezing time should be no less than 90 s. The freezing intercostal nerves can safely and effectively relieve postoperative chest pain. The effect of analgesia of 90 s with PCIA group is the best, but has many side effects.</p>