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Although CD4(+) helper T lymphocytes have been demonstrated to play an important role in antitumor immune response, only a few epitopes of tumor-associated antigens recognized by HLA class II-restricted CD4(+) T lymphocytes have been identified. In the present study, we addressed the question of whether leukemia-associated fusion proteins are recognized by CD4(+) T lymphocytes. Immature dendritic cells (DCs) were loaded with necrotic or apoptotic leukemia cells with t(6;9) or t(9;22) and then cocultured with the dek-can fusion peptide-specific or the bcr-abl fusion peptide-specific CD4(+) T lymphocyte clone. The dek-can peptide-specific and bcr-abl peptide-specific CD4(+) T lymphocyte clones produced interferon-gamma (IFN-gamma) when they were cocultured with HLA-DR-matched but not with mismatched DCs which had been loaded with apoptotic as well as necrotic leukemia cells with t(6;9) and t(9;22), respectively. IFN-gamma production by CD4(+)T lymphocyte clones in response to stimulation with DCs loaded with leukemia cells was inhibited by the anti-HLA-DR monoclonal antibody. These data indicate that the acute myelogenous leukemia-associated fusion protein, dek-can, and chronic myelogenous leukemia-associated fusion protein, bcr-abl, are both processed and presented by DCs to the fusion peptide-specific CD4(+) T lymphocytes.  相似文献   
74.
Postoperative influence of simple thoracotomy and lobectomy on pulmonary gas exchange was investigated in 10 patients undergoing thoracotomy and lobectomy (L group) and 10 patients with simple thoracotomy (ST group). Gas exchange was assessed with hot-wire mass spectrometry and blood gas analyses preoperatively and postoperatively at 1, 3, 6, 12, 24 and 48 h and on days 4, 6 and 13. The preoperative values of alveolar-arterial oxygen tension gradient (AaDO2), ventilation-perfusion mismatch (V(A)/Q) and circulatory shunt (Qs/Qt) were maintained in the ST group. In the L group, however, AaDO2 and Qs/Qt showed good maintenance of gas exchange for only 6-12h after lobectomy and then deteriorated because of peripheral atelectasis, resulting in poorer values than those in the ST group on days 4 and 13. Careful postoperative management, including pulmonary toilet, is essential for maintenance of gas exchange and prevention of pulmonary complications.  相似文献   
75.
Gomisin A, isolated from the fruits of Schisandra chinensis, is one of the dibenzocyclooctadiene lignans. Application of 12-O-tetradecanoylphorbol-13-acetate (TPA, 1 microgram/ear), a tumor-promoting agent, to the ears of mice induces inflammation. Among seven dibenzocyclooctadiene lignans assayed, gomisin A, gomisin J, and wuweizisu C inhibited the inflammatory activity induced by TPA in mice. The ED50 of these compounds for TPA-induced inflammation was 1.4-4.4 mumol. Gomisin A, with an ED50 of 1.4 mumol, showed the strongest inhibitory effect. Furthermore, at 5 mumol/mouse, it markedly suppressed the promotion effect of TPA (2.5 micrograms/mouse) on skin tumor formation in mice following initiation with 7,12-dimethylbenz[a]anthracene (50 micrograms/mouse). It is assumed that the inhibition of tumor promotion by gomisin A is due to its anti-inflammatory activity.  相似文献   
76.
In this study, we analyzed the extent of regression of left ventricular hypertrophy in patients who received small St. Jude Medical (SJM) aortic valves and compared the results with those of another group receiving larger valves. Eighty-eight patients received either 19 or 21 mm valves (Group 1, 25 patients) or either 23 or 25 mm valves (Group 2, 53 patients). Echocardiographic studies were done before the operation and 5 years postoperatively. At follow-up a significant reduction in the left ventricular mass was found for both patient groups (p < 0.0001). Doppler echocardiography derived pressure gradients for both groups were obtained during the follow-up period. As expected, the patients in Group 1 had higher peak pressure gradients than did those in Group 2. However, there was no significant difference between the 2 groups or any significant correlations between peak pressure gradients and body surface area (BSA). Actuarial survival was 84.7% at 15 years for Group 1 and 85.9% at 17 years for Group 2. Actuarial freedom from valve related events was 91.4 % at 15 years for Group 1 and 82.7% at 17 years for Group 2. There was no significant difference in survival or valve related event free curves between the 2 groups. After implantations of SJM valves in small aortic roots, significant left ventricular mass regression was obtained, and the results were comparable to those for valves of other sizes. The long-term performance of aortic valve replacement with small valves was satisfactory as judged by improvement in the functional class of patients and survival statistics, the durability of the prosthesis, and valve related morbidity comparable to that of valves of other sizes.  相似文献   
77.
Arterial blood lactate, pyruvate, and excess lactate (XL) were measured and calculated in 33 patients aged 7 months to 6 years over a period of 2 hours during repair of harelip or cleft palate. When the anesthetic was diethyl ether, lactate and pyruvate levels rose significantly 60 minutes after induction of anesthesia but did not rise thereafter. Excess lactate appeared 60 minutes after induction of ether anesthesia, but it, too, showed no further increase. When the anesthetic was halothane there was no significant change in lactate, pyruvate, or XL. Changes with ether were not age-related, nor could they be correlated with changes in rectal or skin temperature. The responses of lactate, pyruvate and XL to ether anesthesia in the present study were not significantly different from those found by others in adults.  相似文献   
78.
A surgically resected case of giant mucinous carcinoma of the breast that had remained untreated for 2 years is reported. A 64-year-old postmenopausal woman presented with a large right breast mass (17.4 x 16.5 x 14.5 cm). Although she had noticed a mass in the right breast 2 years previously, she had not sought treatment. Mucinous carcinoma was diagnosed by core needle biopsy and she underwent right modified radical mastectomy with a free skin graft. There were no lymph node metastases or distant metastases. Fourteen months postoperatively, she remains well without evidence of tumor recurrence. Although several reports have suggested that pure mucinous carcinoma of the breast has a favorable prognosis, we need to follow this case until the clinical behavior and the outcome become clear.  相似文献   
79.
The close cooperation of both innate and acquired immunity is essential for the induction of truly effective antitumor immunity. We tested a strategy to enhance the cross-talk between NKT cells and conventional antigen-specific T cells with the use of alpha GalCer-loaded dendritic cells genetically engineered to express antigen plus chemokine, attracting both conventional T cells and NKT cells. DC genetically engineered to express a model antigen, OVA, along with SLC/CCL21 or monokine induced by IFN-gamma/CXCL9, had been generated using a method based on in vitro differentiation of DC from mouse ES cells. The ES-DC were loaded with alpha-GalCer and transferred to mice bearing MO4, an OVA-expressing melanoma, and their capacity to evoke antitumor immunity was evaluated. In vivo transfer of either OVA-expressing ES-DC, stimulating OVA-reactive T cells, or alpha-GalCer-loaded non-transfectant ES-DC, stimulating NKT cells, elicited a significant but limited degree of protection against the i.p. disseminated MO4. A more potent antitumor effect was observed when alpha-GalCer was loaded to ES-DC expressing OVA before in vivo transfer, and the effect was abrogated by the administration of anti-CD8, anti-NK1.1 or anti-asialo GM1 antibody. alpha-GalCer-loaded double transfectant ES-DC expressing SLC along with OVA induced the most potent antitumor immunity. Thus, alpha-GalCer-loaded ES-DC expressing tumor-associated antigen along with SLC can stimulate multiple subsets of effector cells to induce a potent therapeutic effect against peritoneally disseminated tumor cells. The present study suggests a novel way to use alpha-GalCer in immunotherapy for peritoneally  相似文献   
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